CA2003867A1 - Food service system - Google Patents
Food service systemInfo
- Publication number
- CA2003867A1 CA2003867A1 CA002003867A CA2003867A CA2003867A1 CA 2003867 A1 CA2003867 A1 CA 2003867A1 CA 002003867 A CA002003867 A CA 002003867A CA 2003867 A CA2003867 A CA 2003867A CA 2003867 A1 CA2003867 A1 CA 2003867A1
- Authority
- CA
- Canada
- Prior art keywords
- food
- dishes
- control system
- tray
- trays
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Classifications
-
- A—HUMAN NECESSITIES
- A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
- A47J—KITCHEN EQUIPMENT; COFFEE MILLS; SPICE MILLS; APPARATUS FOR MAKING BEVERAGES
- A47J39/00—Heat-insulated warming chambers; Cupboards with heating arrangements for warming kitchen utensils
- A47J39/006—Heat-insulated warming chambers; Cupboards with heating arrangements for warming kitchen utensils for either storing and preparing or for preparing food on serving trays, e.g. heating, thawing, preserving
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B3/00—Ohmic-resistance heating
- H05B3/68—Heating arrangements specially adapted for cooking plates or analogous hot-plates
- H05B3/683—Plates having their feeding circuit closed as the kettles, pans or the like are put on
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B2213/00—Aspects relating both to resistive heating and to induction heating, covered by H05B3/00 and H05B6/00
- H05B2213/03—Heating plates made out of a matrix of heating elements that can define heating areas adapted to cookware randomly placed on the heating plate
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B2213/00—Aspects relating both to resistive heating and to induction heating, covered by H05B3/00 and H05B6/00
- H05B2213/05—Heating plates with pan detection means
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S165/00—Heat exchange
- Y10S165/918—Heated and cooled food cabinets and/or trays
Abstract
ABSTRACT
FOOD SERVICE SYSTEM
In a food service system, prepared meals including chilled foods are assembled in individual meal trays (10) and held in the trays for a period prior to regeneration to prepare the food for heating. A
control system of a rethermalizing trolley (12), which accommodates a large number of trays, can discern for itself which dishes (30) in the trays need heating and which are to remain cool. Dishes for hot and cold foods have white and black markings respectively, which results in reflected infra -red signals from sensors (42, 44) of the control system to be of discernably different strengths, so identifying the hot sensors dishes. Dish temperature is continually monitored by the control system by means of thermal contact with thermistors (46), which enables the system to oversee food temperatures both prior to and during regeneration.
FOOD SERVICE SYSTEM
In a food service system, prepared meals including chilled foods are assembled in individual meal trays (10) and held in the trays for a period prior to regeneration to prepare the food for heating. A
control system of a rethermalizing trolley (12), which accommodates a large number of trays, can discern for itself which dishes (30) in the trays need heating and which are to remain cool. Dishes for hot and cold foods have white and black markings respectively, which results in reflected infra -red signals from sensors (42, 44) of the control system to be of discernably different strengths, so identifying the hot sensors dishes. Dish temperature is continually monitored by the control system by means of thermal contact with thermistors (46), which enables the system to oversee food temperatures both prior to and during regeneration.
Description
22/11 ' 89 15: 31. ~021 45(~ 13~8 BARI7~E~R BRETTELL -~->~ MACRAE 12100~ :
F00~ SERVICE S~STEM
~ ood ser~ice system~ are known, particularly for use in hospitals and other in~itu~ions where large 5 n~unbers of ~eals have to be prepared and served, which enable complete meal trays to be prepared some time be~ore the meal~ are wanted, and food in dishes on the .. . . . .
trays to be heated up subsequently (in situ on the trays) for serving at the appropriate time. To preserve it during the intervening period, between p~eparation and serving, the food may be kept suitably cooL by xefrigeration. Such re-heating of food rom a chllled condition to prepare it for servlng, is commonly ~eferred to a~ regeneration or rethermali2ation. Such systems may also find use in transport catering le.g. in~ h~ on aircra~t) and "meals on wheels" dlstribution service~.
Apparatus for use in one such regeneration system is described, for example, in Patent Specification US-A-4 285 391~ That apparatus comprises a rethermalizing trolley wh~ch can be stored in a refrigeration cabinet when loaded with meal trays, and wheeled out ~rom the cabinet when the meals are to be served. The trolley comprises a stack oE shelves, each aaapted to support one meal tray. E~ch shel~ comprises three flat heating elements and food dishes on the meal tray project through openings in t~ bo~tom of the tray 50 as to stand on the elements. ~ an appropriate time the heating elements are switch~d on to heat the three dishes of each tray, to regenerate ~he food in the dishes, and the trolley is aterwards wheeled out from the cabinet for service of ~he ~meal tra~s. The meal trays have insulated covers and the individual dishes can be heated up, within the cab~net, without ,: . . ; , . . ,:: .
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21/11 ' 8~ 15: ~1 ~021 456 13B8 BARRER BRETTELL ~ ~ ALEX E MACRAE C0 l~kl 004 2~3~3~i7 substantial det~im~ o ~he re~ri~erated en~ironmen~
~hich ~ai~ Lins o~her ~unhea~ed) dishes c: ool ~
LI~ ray :tox us~ in hat appara~us land AS
S i n s~m~ similar form is geher~ll the c~se in all S~IC}~
~e~n~ratio~ s~ o~he~ ~o pro~id~ a plhrall~y o:E rec~e~s~s ~ ~LccommodAte r ~ xar~ utLeryJ
corLdi~nent~ r ~n~ , an~1 also three upen-bo~:tc~m c~mpar~n~s in which th~ dishe~s ~or ho~
~4d ~rc r~irleti~ T~Ee three open ~o~t~In compart~ents are i~ registr~ ~ith t~e hea~ing ele~nts of the troltey ~hel~ i~ on~ orien~tion o~ the tra~ on the shelf, bu~ in case there ~hould be no food regen~ration neede~ for ~ p~rticular ~ray i~ is possible lor ea~h 15 tray ~o be ~hel~ed in An oppo~ite oxien~atio~ w~ic~
res~lt~ i~ the ~ea~ing elements ~or th~ s~ not bein~ a~ Ta~ed. EIowe~er, should a tray be suit~bly inserte~ for ac~lva~ion v~ ~ e he~ting elemerlts hen necessaril~ all ~hree el~men~ of tha~ shel~ will 2 0 opera~e, ~ven tho~sh there ~r b~s ~o dish in on~ or more o~ ~he open-bo~tom compartments.
A ~ystem w~ic~ af~ords greater v~r~satility~ in allowin~ for ~e~l tr~s which require some ~t no~ ~11 i~ o.~ Ltin~ elerae~ts Xor a tray ~o be ac:tivate~r is ~sc~i~ed i~ Patent ~pecifl~ation ~S~ 005 745. I~
t~at ~st~m ~le ~ea~ing el~me~ts of ~h shel~ of t~e ~rvice trolle~ can ~e s~itched on o~ o~f indi~idu~lly hy an oper~or~ ~o en~ri~g ~at o~ly those h~ ing ! 30 elements whic~ are ac~u~ need~.d ~re opera~a.
Simil~rly, i~ t~e ~stem de~ribed in Paten~
~peci~ati~n ~S-A-4 203 48~ th~ he~t~ng ~lements can be con~rolled in~ivi.~u~lly~ in ~hat cas~ ~om 2 pro~ramm~d compu~r c~n~ro} ~cility.
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21/11 ' 89 15: 32 ~P021 456 13~8 BARI~ER BRETTELL ~ ALI~Y~ ~!ACR.~E Cn C? 0~15 38~
All three o~ ~ho~e knowrl sy~t.emS ss~ allow~ ~o ~L
~reater or lesser degree r for ~ariatioll~ in the re~ul~ements :Eor hezL~in~T dish~s in the hot ~ood ~ Lpa:r:~cn~:~ of ~ y~j or ~ lc)~de~l ~rolley. q;he 5 sel::ond ~nd third sys~e~s re~rred to permit appropri~e in~ du~l ~orl~rol o~ e heating eleme:~ts, but in ~11 three cas~s an opera~or has eithe~ to inspect each tray, or be supplied ~it~ the rele~an t in~ormation a~aout ~he make-up o ~ he tray~, in order to know the 10 de~all c)~ ~e heat.ing requiremen~. In the third sy~tem r ~or exa:~ple, a printed recor~ o.~ ~e ~e~uire~en~s is prepared in order that the ~e~ermalizirlg ~:02~rol system c:omput~r can be P:~gxamm~
T~re is ~ ~y~tem de~cribed in patent spe~ a~ion uS-A-4 584 466 in ~hi~h the ~eating elernents can onLy be ~c~tiv~ted in the presenc~e o:E a dish wh~c~ ~c~u~lly re~uires heating~ This is a~hieved ~0 by providirlg the hea~ing ~lemenis in ~e base~ o~ ~e di~h ~ th~elves (s~ re~iring specially ~snstruc~ed dishes~ ~n~ using c:ondt~ ors and di~;h-enga~ing contac~ts in t.he tray ~o ~pply pow~r ~rom sup~or-t rails to such in~talled di~hes; ar~y dish ~ithout a h~ting element 2~ theref~ore remAins u~heated, re~ardles~ o -~s p~sition in khe ~ra~. ~uite ~part :Erom such a ~stem re~uiring a spe~al kirld o:l~ dish, ~e supply o~ large elec~ri~
çur~e~t~ through readil~ se~ r.onta~g, :eire~: from Ldil~; to ~ ~ray and ~hen from ~he tr~y ~o ~h~
30 dis~esr i~ likely to give trouble from sparki:rlg ~nd ~rring o:E the ~ont~c~s, ~n~ is ge~er~ll;y an ~n~e~:Lra~le arr~ n~.
It i~ ~ obj~ f the pre~nt in~ntio~ to 35 pro~i :~e improved re~malizing apparat~s o:E the ~eneral kind illu~rat~d ~y the systems ~efer~ed ~o~
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2~ 9 15:32 ~021 456 13~8 BAR~ER BR~TTELL ~ ALE~ E MACRAE CO ~ 006 ~38~7 ~he inven~ion p.ruvides, in o~e o~ it~ asp~cts~
re~erm~ ing ~pp~r~tus s~itable ~or u~ in re~e~ratins c~llled food i~ a food se~vice sy~tem in whi~h prep~red meals in~luding ~hilled ~ood~ are S a~sem~l~d in individ~al me~l ~rays and hel~ i~ the ~r~ys ~or ~ period pr~'or to rege~era~ion to prepare th~
food for ~ati~g, the appar~tus comprisin~ a plurality o~ in~ivld~ally ~ont~oll~la heating ~its ~or heating food ~s necess~ry in indi~id~l fOOa dishes wi~hin a tray, and ~ cont~l s~ste~ arrahged to ope~ate ~he he~ing ll:Dits selectively s4 as to hea~ food reguiring re~ener~tion ~ut not to heat ~ood whi~hlit i~ xequired should re~ain cool, ~hara~erised i~ ~hat for effe~in~
oper~tlon o~ those heati~ unitR only wh~h are lS as~o~i~t~d with di~h~s hol~ing food to b~ he~ted ~he c:ont:rol system is ~rranged to reflect radiated sensing signal~ o~f ~h~ dishe~ and to respo~ to ~he xe~lecte~
siynals r th~ u~e of ~oc~d di~hes whic:h are suitabl~
dis~inctive a~ be~ween ~o~ ~ood dis~s ~or holdin~ food ZO whi~h i~ ~o be heated ~ col~ food dishes for holding ~ood ~hich is ~o rem~in unheat~d ena~liny the control s~s~m to disti~g~lsh be~ween ~he hot a~d ~ol~ ~ood di~hes from dlfferen~e~ in the re~lec~ed ~i~nals~
T~ sen~ing signal~ ~y ~ infra-~ed ra~iation and, in R simple fo.r~t di~he~ for ~tai~ih~ ~ood -~o ~
h~ated ~ay ~e white or m~rked s~i~ably with a ~hite patch, and dlshes ~hi~h are ~o re~ cl ~nhe~ed bla~k or markea w~ a ~l~ck p~ch, so tha~ th~ refle~ted ~ignal~ are o:~ discernably ai:ceferen~ ~reng~h~ a~
between dif~er~ ca~gories of dish.
A ~en~or u~ ompri~ing An e~it~er and a de~ector ~:an c;on~reni~ntly ~e ~ oca~d ~dja~en~ ~o a di~h pbsition~d for h~a~ing in order to ~e:Elec~ ~L sig~ o~f s~ ~nd to pas~ an lndicatio~ o~ the ~tren~ h oE
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.-21/11~8n 15:~ ~021 4$6 13~ ~AR~ER BRETrELL ~ ALEX E ~IACRAE CO 1~007 38~7 t}~e reflect~d signal ~o the ~ontrol sy~teln lHhi~h ~o di~cern~; whe~her o~ Ilot ~he ~ood in ~h2!~ ~ish is to b~
heate~ .
S The inv~3n~iorl p:rovide~, in a~other of it~ asp~t~, x&the; :malizing apparatus suit~:e for u~e in regeher~ting chille~ food in a ihod service ~ystem i~
whiGh prep~rea meals lncludin~ ~hill~d fvods are as s~nbled in lndi~rid~al meal ~r~7s aTld held in the ~ra~s ~or ~ period prior to regen~r~L~ion to prepare the food for e~tin~ r the apparattls ~omprlsing a plurality ~f lndividu~lly ~on~rollable h~a~in~ units f~r heating ood ~s hecess~ry in individ~al food dishes within ~ray, ar~a ~ control ~ysteIn ~rrc~nyed ~o op~rate the he~ing url~ sele~ively ~o ~s to heat ood xetluirin~
reg~neration but not LO he~t food which .it i~ re~uired ~ho~d remaln ~oolt ~hara~eri~e~ in t~a~ ~h~ ~vn~rol ~ystem ~omprises ~eans whe~eb~ ~he ~mperature of ~od the di~hes in ~ ~ray can ~e moni~ore~ prior to and ~0 during regener~tlon~
T~e ~e~pe~a~ur~ o~ ~e fooa may corlvenie~tl~ l~e moni~orad indixectly by monitoring the ~empera~ur~ of dishe~ holdlng th~ ~ood i:n the tr~ys~ In a convenient ~5 arran~emen~ e~sor Uhi~ ~omprisi~g a ~er~istor or o~her te~p~rature-respon~i~e electrical ~.lemen~ is located adja~en~ ~v ~ dish positione~ ~or heating in order to ~e re$po~sive to ~h~nge~ he temper2~ure o~
the dish ~:nd to pass a ~orrespondl:ng signal to the 3 0 ~o~t~ol ~y~tem .
Mc)ni~orlng ~ :~oo~ ternp~3rature can be of ~va~tage both ir~ e3~ ri;lg ~ the ~ood is kept ullder app~vpri~e te~Lper2ture ~o~i~ion~ prio;c ~o 3S regen~r~Ltiont a3~d in con~rollin~ regene~a~io~
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oa 1~ o DARIS13R ~R~3TTnLL 777 ALr~ IACRA~ CO l~ ooo .,J
prooess for sui~le tre~en~ o:E ~he :eoc)d and e~r~y ~c~n~er~ation .
The}~e n~w ~oll~ws ~L deta.iled aes~rip tion, ~o be S rea~ with xererenc:e to the ac~ompanying drawin~, of a rood servi~e sys~em w~i~h ~llustra~e.s tha in~ention by w~y of e~ample.
n . he a~CO~rLpa~ying dra~ings~
a .,, ~i~re 1 is an o~eJ:all ~.ie~ in perspective ol a :c~t~:cmall2ing trolle~ wi th o~e of a plurality o m~al ~rR~s ~ho~L ~nstalled on a shelf o:E the ~roll~y;
Fi~re ~ is a di~grammatic pla~ o:E compa~ent~
o~ a me~l ~ray;
Fi~u;~e 3 is a ~riew in ~r~sS--~ectio~ through par~
~0 . or a mF~I f~, 6h~w;~ng A hoL ~uu~l ~$isn ln position in the ~r~y;
Fl~Lure ~ shows one ~ensor u~it of ~ kind _ . . .
utilised in con~:le~tion ~ith eat~.h nf ;;~ pltl:rAli~;y ~5 heating ele~ents of ~he ~rolley~
F~ is ~ schem~ uit d,iagram o~
~ontrol ~ircui~ry o~ ~he trolley;
Fi~ is ~ se~sor unit cir~uit dia~ram;
~ is a ~chemati~ s~ tlon o~ a sensQr 2~La~rix ~wi~c~irLg arra~geme~lt; and 3 5 F~re ~ i s a ci~cu.it dia~r~m showing in r~ore detail a matrix used to c:Qn~rol individ~al ,~ , `' .
21~ 9 15: ~3 1~021 45~ 13~8 BARKER BRETTELL ~ ALEX E MACRAE CO l~b 00 ~perati~n of he~-ting el~en~s lr~ ~ common a.c~
power s~rae~
In a ~ood serv~e system, ~or exa~ple ~or distributing lar~e ntlmhers o~ pre-prepared meal~ ~o ~he pa~i~nts in a hospit~1, use i~ made o covered me~1 ~r~ 10 i~ w~ich ~omple~e me~ls can be ~rranyed ~or ~e~vice ~d hel~ f~r a time prior to ~a~ing r and r~h*rm~lizing ~rolle~ 12 in w~i~h ~he tra~s ~a~ ~e 10 sta~k~a an~ by me~ns of w~i~h ~hilled ~o~d in the ~rays c~n be re~erated at the re~ui~e~ ~ime.
~ al~ m~y be pxepared in a sin~le ~entral ]citchen where ~lso the individuc~l meal tr~ys 10 ~re ma~e up in accord~ e witll m~nu sele~ions m~d~ by the patienks.
As illu~trated by ~i~ures 2 and 3, ~ lower ~ck 14 of each m~1 tray pro~ides an as~ortment o~ recesses 16, 18 and 20 for ~commodat~ny, respe~ively, a d~inking veRsel, ~tlery, and a ~ld~ di~h or plate ~for, ~erhaps, bread ana/or but~r, chee~e e~c.). Alsc provid~d are ~hree heating comp~tm~nts ~2, ~4 ~a 25 in which aish~s can ~e placed ~or ~ood that may ~eed regenera~in~ after ~hilling; a~ illustrated, the ~ompar~ment ~2 wo~ld be to hold a ~ain meal dish or pl~tet and the compa~L~en~s ~4 ahd 26 could be for SQUp and hot pudding, respectiv~ly. ~ow~v~, as will beco~e ~pparent hereinakte~, dishes ~c~n h~ ~la~d in ~ny of ~he he~ting co~pc~rtments 2Z, ~4 and 26 wit~ ~ood tha~
is not to ~e he~ted up be~ore ea~i~gr withPu~ ~ny ~0 ~is~d~tage ~or example, ~here may be a ~ot main cour~e dlsh in ~p æ ~men~ ~ ana a dish for ~ puddi~g t~ b~ ea~en cold ;~ ~omp æ ~men~ Z5~
i A~ ~n be ~een ~rom Fi~ure 3, each o~ the h~tin~
3S compar~n~s ~2, Z4 and ~6 (~ly ~ompax~ment Z4 is shown) h~s a botto~ wall ~onmed by ~n alumini~m heat . : ; .: : , : ~ :
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21/11 '8~ 15:3~ ~EP021 45~ l~e8 BARKER BRETTELL ~ ALE3X ~ MACRAE CO 1~1010 38~
t~ans~e~ pl~t~ ~ ~hich is retained in aIl o~e~ling th~ough th~ ~o ~om o:~ the law~r d~k 14 o~ the tr~y.
The ~r~n~:Eer pl~te 28 i~; in the :~orm of a ;Ela~ c on which a food dish ~ O ~;tands when lod~ed in the 5 ~ompar~ment 24. ~he h~ r~m ~ f;~ f tho tranc:Ec~
plate 28 is slightly abo~re ~he s~rxou~ding bottom su:~face oi~ the l~r2~r a slight rece~3 so being pro~id~d ln ~he tray :~ot~;om beneath ~he pl~te.
13ac:h ~eal tray compr:Lses also an upper deck ~2 whic:h pro~7id~s a cov~r f~or th~ loaded lower deck 14 ~
an~ each o~' the two ~eGks of ~he t~ay i~ d wifh a thermally insulating polyure~thane i~oam fillin~ 3 4 in o~der to help ~Lint~in ohilled ~ood in th~ tray at a ~uita~ly low tempexatur~. ~ox ~Ie ~n~ag~ prior to ~ng regenerat4d ~or eati~s~
Alterna~ively, at lea~t th~ low~r ae~ 14 of the t~ay may ~e ~illed with ~ so~cat~e~ h~utec~ic~ liquid~
the ~ray bei~g ~rozen before loadi~g a~d enabli~g food to be kept ~r up to ~wenty ~our hour~ in the ~x~
prlor to rege~er~ti~n.
The pr~psr~d meal ~ays, with ~ood~ th~t require 25 i~ being ~hilled in ~heir di~he~ he tr~ys, are Rta~ked on shelvçs 3~ or ~he ~er~ice ~rolley 12. In the trolley illustrated i~ Figure 1, there are eight ~helves accessible ~ro~ ~ch o oppo~i~e sides o~ ~he ~roll~y and e~h shel~ can accommo~te ~wo ~rays side-~y-side7 the ~roll~ ~hex~re c~rrie~, wh~n full, thixty-two me~l trays.
I~ ~he upper su~:i~ace o:C ea ::h shel:~ 3 6 th~re are ~;ix ~ t, di~c--l~ke, alum~niu~ heating pl~tes 3~ whi~h 3S cor~espond n size a~ po~ition with the heat t~nsfer pl~tes ~ o~ two trays 10 in~talled on the shel~ The : ` :
:~, 21/11 '89 15:34 ~ 45~ 1~68 BARRER BRETTELL ~ )~ ALEX E MACRAE CO 1~l01l Z~
~e~lng pla~es 3 8 ar2 raised ~lightly ~o~e the ~pper surfa~e o~ the chel~ in order t~ lo~a~e ln ~he ~ lar xece~ses in the bo~to~s o~ he t~ys ~ b~e~th ~he ~r~ns~er pla~es 28; ~he p~rallel hea~ing plates ~ and 5 h~a~ tran~e~ pl~es Z~ e so ,arranyed to abut f~Lce-to-~ace. 131~c~ric hea~lng el~men~s 39 ~igu~e~ 5 and 8 ) ar~ ~rranged in ~ c~on~t i or~ anner ~o~
heatins the hea~ing pl~es 3~ .o ~he h~at ~nsfer plates ~ a~d t~e ~oo~ dis~e~ 30 skanding ~n them ln 10 the t3~ys 10 Op~ra~ion of ~elec~ed hea~in~ elem~:nt~ at requi~e~
kime~ is c~n~rolled automa~ically by an elec~t~onic~
control sy~;~em o:E the ~rolle~ whlch i~clude~ ~L
micxoprocQ6so~ ord~r t~Lat the control s~s~m can know w~ h heating ~lemen~ are! re~uired to be oper~ted and c~an continually~ monitor -the ~e~npe~ u~ o:E ~he f~od ~ishes in the tra~s, ~he system lncludes ~en~or UIli~:5 40 itte!d into th~ heati~g pla~es 38 ~0 ~ indicat~d ~y Fi~ 1 ~which shows onl~ ~he 13e~Lting pl~es fo~ o~e shel~, but all the shel~:s ~Lre in f~Lc~ the ~e) eac~ he~L~iny platq 3~ h~s ~r~ openir at its centre inl:o w~ h i~s as~;~cia-~ en~r u~it 4n 25 is fitt~ed. A fl~ top su~:Eace~ o-E -the sen~o~ unit is fl~sh wi~h ~he upp~r ~ur~ac:e or th~ heat~ng pla~e.
E~ch ~nsor unit 40 ~Fi~re 4~ ~omprises ~n in~r~-red em~ter ~ infra-red det~:ctor 4~ and a 30 thermistor 46, ~he ~ee compo:~lent~ ~eing mounte~l on ~
printed c~ r ::ui~ ar~ 4 and p~t~ed to~eth~r in a ~lear s tir~g resin ~, An uppermo~ e~ge- of the thermi~t~r ~
is c::oinciden~ wi~ op ~urface o~ th~ sen~or unit so as to engage kh~ urld~rsur~ace Qf the asso~iated he~t ~S t~Lns~er plate 28 o~ ar~ inst~lled t~ay; the thermist~r i~ so inst~ ,d to ~e ele~ric~l:l.y resp~ to ~. :
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l1:11 8~15 35 ~021 45~ 13~8 BARRER BRETTELL ~- ALEX E MACRAE C0 1~012 `
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varia~ions in the temperature ~ tr~n$~er pl~t~
28. ~he ~hree Compo~en~s ~ ~ 44 ~n~ 4~ o~ ~he ~it ~re ~le~tri~ally interco~ec~ed hy the pxinted cir~uit bo~rd 4~ a~d three le~d~ 50, 5~ ~nd 54 .~rQm the ~o~rd provîde for common ground, inpU~ ~d ~U~pU~ co~ne~tion~
respe~ ly Wlth Xe~erenGe ~o Fi~ure 5, the ~on~rol sys~em ~omprises in addit1~ to the Inicropro~essor ~?U~ ~
real-time ~R~) clo.k which en~bles the system t~ kee.p ~ra~k o~ t~e ~ime o~ day. ~ di~it21 display and keyp~d, ~omm~ica~ing with the mic~oprooessor ~h~ou~h.
A~l interfa;:i~g chip ~PIA), ena~le c:oImnuylicatio:~ hetween the microproce~or an~ an oper~or~ ~m~r~ a~pa~ity i~
~ ia~d ~hr~ h ~.PRO~ a~d P~M ~a~ ies An analogue ~o digital conver~er (AD~) en~bles ~ol~ge signals ~rom ~he se~sor units 40 to be read by th~ CPUO A se~ond inte~a~ing chip (VIA~ link~ the CP~ to ~wo wirlng matr 1~es 5~ and ~ r c~n~ l of ~he heating elements z~nd th~ eensor units 40, :cespec:~i~ely.
q'he ma~iCes S6 ~nd 58 en~ the ~in6~y - six hea~iny elemen~s ~nd the I~ e~y~ix :~ie~sor unlts t there hei~g s.~x ~ e~ch on ea~h of ~ix~een sh~ s) ~o be controlled indiv~dually. Ea~ ma~ri~ i~ a~ 8 x 12 arra~ement ~ tw~ty di~tinct condu~iv~ pa~hs con~idered in colu~ns ~nd row~, e~ch heating elemen~ or G~n~f-r "~ in~ ~n~ a ~ 0s5 ~ unique ~om~ t~o~
o~ ~olumn ~nd row pa~n~ Lu~ ivi~ trol ~n derin~ the sens~r uni~s ~0 in the ~tr~x 5~
~irs~/ the ~welve row paths lead fxo~ ~ ~a~si~or s~chi~ devic~ 60 ~nd t~ eight column pa~hs le~d ~o a~ a~al~gue switchlng devi~ r both of which devic~s are u~d~r ~h~ ~ontrol o~ tkte VIA ~hip. Ou~ptl~ n~ls ::
1R ~IR ~n~1 a~fl 1 ~R RARRT~R RRF.TT~TT. ~ A~.FI F l~lA~'RAlZ ~n la3n1 1 2~6~33!~
11 .
xom the analogue switc~ing devl~e 6~ ~re p~ssed to the ~C ~or ~onverSio~ ~nd onward tr~nsm~sSion t~ the CPU.
~ onsidering the hea~ing ~lemen-ts in ~he matrix S~, the twelve row ~h.~ fr~m ~ 6~ ~ tW4 ~r~ ~s ~ i ght c~lumn. pi:L~h~ d to e~. b~nk ei~ht ~iac~ both ~Lks.. o~ s being urlder the ¢~nt:~ol c~:E thc ~ ~h~ p, 3~ b v4~ .y~ 0 energise the hea~ing eleme~t~, bu~ ~o prevent mains 10 ~-olt~ge reac~ing ~he ~P~, the ~r~acs are not directly ~onnected but are isolated optically ~rom the main ~ir~uitry by opto~iaCs~ To inCre~se heating elemen~
life a~d red~ce in~erf~rence, th~ ele~me~s ~re swi~h~
on ~ of~ only ~hen -~h~ mains vol-~age cy~l~ 15 at 1~ zero. The ~otal loading o~ all the-~e~in~ element~ o:E
~he tr~lley would ~e 288kwr but ~y using a pulsed pow~r sha~i~g ~cahniqu~ ~he ~xolley is ~nA~ to op~rate ~ro~ an ordinar~ 13 amp ~k~ pow~r supply.
Th~ sen~r uni~s 40 serve ~wo purposes~ As herein~ re ref~rred to t thrvugh u~e of ~he thcrm~to~s 46 th~y ~~ Le~ nal v~.riations in t~p~x~-~ure ~ the heat tr~nsfer plates 2~ and ~o (~ndir~ctly) tv monitor food temp~ture. ~owevex, ~hey ~urt.her have an essenti~l role in i~e~ti~ying whlch dishes xe~uir~ hea~ing ahd whi~h do no~ when the l-. i m~ ~ rr.~ w~ 4n.. ~ ttcr -~ UDc~ lo~ i:l effe~te~ thr~u~h u~ ln~F~ eml~ter ~ and det~c~ 44 o~ each unit.
D~ a~ CI;:L ~2~3 h215 ln lt: a small ape~u~ 68 (~igure 3) W~ich is ~o ~iligned with ~he ~nso~ u~t 40 o~ ~he ~ iate~ he~tins plate 38, whe~
the ~ray i~ i~istalled on ~ ~rolley shelf 36 t th~t it 3S ~ms a window above the inrra-red elem~n-~s 42 and 44 ~ the Uriit. ThR sen~or U~lit 40 ~an 60 ~view" the .i,, ~ .
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15: 3~ ~021 45~ S BARKER BRETTELL ~ ALEX E MACR~E C0 1~ 014 38~i~
bott~m o~ Any ~ood ~ish 30 in the heati~ compartment 24 o~ the t~ay hy r~;lh~in~ An 1n~ r~ si~nRl ~ff the ~ish :by mea}ls of it~ in~ red ~lemen-t~ 42 ~Lnd 4~.
~ The the~mis~or 4~ i~; p~ ioned asi,d~ from the window 5 68, so as ;~ o enga~e the und~ide of l:~e ~eat t:cansler pla~ Z8 ~ ~ Each or ~e ~oo~ di~hes 30 used in ~he c:~mpar~men~s ~ o~ the ~ray is iclenti~ied as one to ~e he~te~ or not, ~s the c:~se may be y by means of whi~e or a black ~:respec ti~ely) ider~ yir~ patch ~n lo its ~ om su~face oppo~i~e the winc~ow 68 ~he ~cfl~c~d ~:igrlal whiah ~::: in:Fr~ cc~ ~ctcc~ r ~ oi~ cn ~ct;ivated sensox uni~ ~c~ives :~rom a di~h with ~ whi~e marki~g is of a markedl~ ~lif~e~ent le~reL i~rom that which w~uld h~. r~ rP~ fr~m ~ h .w~ ~h ~ hlA~k 15 ma;:king (or ~si~il~rly in the a~senc:e G:E a di~h from the ;:ompartment) and the OUtp~lt signal rrom ~he sensor unit 40 ~ ~ whole i5 con~equ~n-~.ly n~ e ~if~erent order ;Ln ~he ~wo ~a~;es. Ac~ordin~ly, provided that in prepara~ion of th~ meal tx~ys ~ishes with whi~e 20 mRrkings are tlsed to con~airl ~h~se f~d~ ~Thlch need to ~e :~g.c~c -~ted,~ ~ibllc~b w1LlL IJla~ e~ ,y~
con~in ~hose roods which do r~o~, the~ con~rol syst:em is ~c~le to ~e~e:~mine au~oma~ically whlc:~ he~ti~g elemel:Lts ~eed to be ~perate!d }~y dlstinguishin~ be~wee2~ the two 25 level~ ~f signal~ ~ein~ produ~ed by the sensor ~ s 4~.
Power for ~he control sys~em comes prin~ipally f~om an i~ternal r~h~ge~ble batter~, mains power ~ei~g re~ulrea only ~r ~he heating ~leme~ts ~uring ~ood regener~tion~ d~in~ which ~ime the b~ttery can also ~e ~ha~ed.
~ he system i~ u~de~ ~he ~on~ro~ of a pxogr~n ~to~ed in ~h~ ~P~, whiGh pro~r~m can be ~han~ed....to ~5 vary ~r up~ate the system ~hen re5uir~d, ~o~ ex~mpl~ to ~eet statu~ory re~u~tions ~or ~he sa~ s~o~ge, . :
22~11 '89 15:31 ~21 45~ 1368 BARKl~R BRETT~LL ~ BIACRA~ l~boo3 2~q~3~1~i7 handling and regeneration of chilled meal~. When t~
system is first powered up, the program set~ all the hardwate to a predetermined set o~ conditions. Once this is done the program sta~s in a loop constan~ly reading the keypad to check ~or any input by the operator, and checking whether the time has been reached fox regeneration; i an input is detectea the program will branch off from the mai~ loop ~o perfoxm . the required task.
Every two minutes the program jumps out of the main loop in order to activate and read the ~ensors 40 (one by one) and so monitor the arxangement of food dishes 30 and their temperatures~ ~his information is recorded by the CPU in the memory. ~he CPU is ~hereafter able to detect any change in the arrangement and temperature of the food dishes b~ comparing the new information each ~ime with that previously recorded~ One minute before it is time to reqenerate, the program branches off to make a last check o~ the food dishe~ prior to regeneration, and if all is satisfactor~ the program then ~xanches o~ into a regeneration routine.
Continual monitoring of the food dish temperatures prior to regenerat.ion can be important, as it may be es~ential that the temperature of chilled ~ood held in the trays does not rise above, sa~, 10C. .Should the control ~ystem detect that such 2 ~ rise i~ temperature has occurred it will cause an aLarm signal to be given together with an indication ~o tlle operator as to which dish is a~fected.
During thei regeneration routine, the system continually activates each Gf the required hea~ing element~ in turn, also continually monitorin~ the : , ' : . :: '~
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9.1~P.KE~R BRI~TTELL > ~ L~
2 1 ,~ 1 1 ' 8 ~ 3 7 ~O
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;2~)1~3~,7 tempera~u:::es o~ ths dishes. Tow~rd~ the end o the ~ou~:~.ne, ~e he~L~ing elesne~; ass~ciated wi~h di~he~
whi~h ha~e alrea~y rea~hed their resuir ~l temp~ratu:re are acti~ated by ~e control ~ys~em ~nly a~ much a~ m~
5 he require~ ~o m~intain ~ha~ npera.~u~e..
This ~oOa se~i~e systeTn so I t~kes a~caun~ c~
~ra~ing load~ o~ m~ ompone~ts to en~le ~he ~ Pm -~o use a ~lni~u~rL o~ ene3~y ~luring regeneration.
~egardl~ss of ~he type o~ food ~ein~ reg~nera~a th~
~ n~ ~pC~3~ r ~ ne neated ~oo~ ~omp~rt~e~ts will be ~ub~t~ially ~he s~me.
Inst~ad o~ indi~idual progra~mi~g o~ troliey~ by keypa~s o~ ~ach, ~olle~tiv~ pro~x~mmin~ by an inra-red or ~he~ tr~n~mit~e~ could o~ cour~ b~ employed~
Further di~Gussion o the operatio~ o~ ~h~ s~nsor u~i~s now ~ollows~ Figure ~ i8 a ~ir~uit diagr~ru-~ r a ~n ~ na~l- u.ll~, wn~ o~sider~d as ~wo varia~le re~is~ors forming a potenti~ divider, the two ~ari~ble resi~tors bein~ ~ormed by th~ in~ra-re~
det~ctor 44 and ~he thermisi:or ~ As ~ whol~ u~it, ~he~ sen~or ~an b~ consi~ered a~ a de~ic~ ~t pro~uce~
Z~ an output vol~age tha~ is rela~ed to its ~e~pera~ur~
~d. po~ltion ~ ive ~o a re~lec~i~re sur~ace, 1. e . t~
bottom ~ur:~ace of ~he dish ~0..
~he ~io~e 1 is inGluded ~o prevent ~h~
30 i~te~action of ~h~r ~nsors ~ Lll~ ma~rix, ~ cau ing the signals ~ low in ~ne di~ection or~ly.
As he~einbe~ore described and shown also in Fiqur~
he ~en~or units 40 ~r~ con~e~te~ ~;o a~ ~o or~ a 35 matrix. Th~ ri~ cor~ ts or ~welve powe~ ~upply li ne~ (the row p~3 ~ach ~ne being con~rolled by the , . ~ -, -; ' .: , ,. '; , "' , , :
22/11 '89 15:32 ~021 456 1368 BARKER BRl~VrELL ~ MACRAE l~boo4 zoo3a~
transistor switching device ~0, and eight signal lines ~the column paths) connected to the analogue switching device 62. The analogue switch routes the signal on one o~ the eight signal lines to the analogue to digital converter (A~C~. Exactly which signal lina i.s selec~ed depends on a binary num~er from 0 - 7 belng sent to the analogue swi~ch hy the CPU.
. , In order ~or the value of a particular sensor unit to be reaa, the CPU must ~lrst s~itch on the transistor that powers the sensor unit in questlon through the correspon~ing power supply line, an~ then send the required binary value to the analoyue switch to connect the output signal from the sensor unit, on the coxrespond~ng ~ignal line, to the analogue to digital convertex; although there are eleven other sensor outputs connected to this signal line, they are all switched off leaving only the signal from the sensor unit in question to be present. ~hese two opera~ions ~0 actually happen simultaneou~ly with the CPU sending a slngle binary value to the VIA that controls the ~ensor matrix.
!
It can be seeIl ~rom this that only one sensor may be read at a time~ To increase the accuracy, each sensor is actually read sixty-four times and an average taken~ .
The output ~rom each sensor unit gO, once read by the CPU, is a numerical value ~etween 0 and 255. This value is a representation of the type and temperature o~ the dish 30 with which the sensor is associated.
Initially~ he~ore the trolley is loaded, all sensor units will return a low value ~e.g. 20) there being slight variations between the ninety-six : ~
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21/11 '8~ 15:38 '~021 45~ 1388 BARKER BRETT13LL ~ ALEX E IIACRAE C0 l~bO18 20 [)~3fi~
1~
re~dln~s. ~y ~lue v~ Li;Eferen~ ,~rom ~he re~t would ~n~icate ~ha~ a problem e~ists, an o~jec~ obscuring ~he s~n~or ~or ~x2~npl~ r an~i a wa~ing :bu~er would be soun~ed to al~t t~e operator.
Once ~e ~rolle~ is lvaded and ~he ~ensox~ ~ave been x~d, all ~he val~e~ should have d~opp~d ~tle to the lower t~nlpera ure o~ ~he dis~ , wheth~r r~3~uiring h~;~tin~ ~- no~r O~ ~udl~le~ e same if n~ pla~e i9 la present; ~ensor ~nits ~sso~iated with dishe~ ~hat requixe hea~ing, h~vi~ white pa~che viewea by the sen~or ~its, w~ 11 re~ur~ a ~Talue ra~he~ lower th~n those t~a~ are ~o r~aln cold ~i . e O -kho~e ~aving ~la~k patGhes). A~y rise in valtla (i.e. w~en ~the ~rolley i~
fir~ Loaded) ~ould indl~te ~ p~zte o~ ~oo hi~h a temperature, ~ke op~a~or bein~ ~arned should thi~ be 'th~ CA :EI E~ .
S~sequ~nt rea~ing~, ~et~een t~e ~lmes of loaaing ~d regen~ration r will ~how a gra~al i~creas~ in v~lues ~ the ~e~perature ~f the food on the ~ish~s ri~e~ ~o~ar~ e ~mhie~t ~e~perature, ~his be~n~
~low~d b~ ~he inB~la~ed tray. A wildly differen~ ~lue ;Ero~ t~ ree~ would point towards ~ prvble~ wi~h t~e 25 t~a~r ~uch a~ ~n ~mproperly locat~d l~d reducing t~e ~mot~n~ of insu~ion 2nd cAtl~ing the gre~te.~ in~rea~
in te~pe~ture~ ~
From ~h~a readi~gs }~far~ the ~olley was loaded 30 I:he CPU i~ al~le t~ ~al~ulate 2L ~ralue ~at ~o~re~ponds to the 10 c: l~mit ~at the . ao~ mu~t remain belc~w ~efQre regener~ionO Ea~h se!nsor xeading is compaxed with thi~ vallle ~nd warning ~i~7en sh~u~d ~ny ex~eed i~.
3~ Du~ing re~ er~t~on ~e r~2dings ~ill rise f~i~ly ;~pi~ly ~l~ e food temper2Lture. Rea~ing~ a~e n~w . i ' ~ ' . -- ' ~ "''`............ "' ''':.:, Zl~llsa 15:38 ~021 45~ 13~8 BARRER BRETTELL ~ ALEX E ~IACRAE CO ~ 01~
2~38~
oompa e~ed with a~o~her predetermL:Lned v~ e that indic~tes the 70C t~at th~ :~oo~ m~s~ reach to be prop(2rly r~gener~ted.
The ~P~ i s Able to ~ e~e~riate ~etwee~ :Evod pro~iuc~t~ gre~tly ~ erent Ele~ c~p~ities b~ ~heir t~mpe~ ure readi~g~ during re~erlexatio~ nd regu7 at~s th~ amoull~ o~ hea~ing ~iv~ to each dis~ accordin~ly in ox~er lo c~mplete the regenera~iorl of alL the ~eals at tihe saune tim~. ~ow~er, ln praciice mos~ food produc~
re~ the ~ame ~moun~ of he~ing and lit~le such ~ervention by th~ CP~ g~n~rally ~ccur~.
m~ aetailed dascription now ~OllO~ wi~h ~5 ~e;ee3:en~e to Flgu~e ~, o t:~he c:ontrol m~Ltri}c 5~ for t.~e heat.ihg elem~n~ 39.
~he twelY~ row pa~hs a ~o 1 lead to ~h~ ba~};
6~ a:E t~el~ xiac~ ~na ~h~3 eiyh~ ~ol~unn paths ~ to lI
~a lead :~rom ~he :4ank 6~ c~f ~ight ~riacs . I!Iains a~ ~.
~ol~a~ applied to the m~trix ~roug~ the tri~c ban~c~ . The p~r~icllla:~ heatlng el~ment 3 ~ indi~ate~ in wing ~11, for example, ba actlva ted onl~ by t~e m~rix com~inatic)rL Ce~
~5 y Ine~s ~ ~u~ a ma~r~ a p:rim~Ly ~ondu~t~e pa~h ~r~u~h ~ J;;irlgle ~lement i~ c:reated b~
~ny ~ele~ted c;:ombina~ion o~ single ~ol~n ~Ld r~w paths, a plurali~y oi~ ~ec~ondary condtlc~iv~ paths are pc)tentially ~eated throu~h combinations of elements in ~eries ., ~rhis would result ~ ~ power wast~ge / and some heating vf elements which~ a~e in~ended ~o remairl nac~ive, urll~ss me~s~l~e~ are ta}cen t~ block all ~uch ~c~nd~Lcy pat~ks.
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::~ , : ;.. : -~~ ~021 4S~ 13B8 BARI~ER BRETTELL -~) AL~{ E ~IACRAE (~0 ~102~
1~ ~
By me~n~ o~ ~ pair o.~ oppositely o~ien~ed divdes 70 an~ 7~ at t~e ~.c.. irlput of the tria¢ ~ k 66 at the he~d q~ the ~olumn path~ A ~o ~, ~h~ mai~ aurrent ls split into it9 negative and positiv,~ comp~nen~. One S compone~ supplies the fo~r p~-~hs ~ to D and the o~h~
compo~en~ ~upplies the p~ths to ~ Each of kh~
~ran~er pa~h~, b~ween a row an~ c~lum~ r l~clu~e~ a diode 7~ whi~h is orie~t~ed appr~pxiately t~ ma~h th~
pol~ri~y o~ the column pa~h to which i~ is ~o~n~cte~
10 A11 ~l.re o~ t bo f~n~r ~ 5 ~onnec~d ~o oach o~
~he column~ A ~o ~ are there~ore un~direc~ional i~ fhe s~ ense. Sin~ ~e ~x~iqtion o:C d con~lv~ h r~qul~ on~ ~-E ~w~ ~.rans:Ee~ Paths co~ec~ed ta the ~me ~olum~ pa~h r ~n~ one o two tra~er pa~h~ ~onne~ed t~ ~he sam~ row p~h, to b~ a reverse curr~nt path, ~locking o~ all such secondary E~t~ Lc:hlev~
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F00~ SERVICE S~STEM
~ ood ser~ice system~ are known, particularly for use in hospitals and other in~itu~ions where large 5 n~unbers of ~eals have to be prepared and served, which enable complete meal trays to be prepared some time be~ore the meal~ are wanted, and food in dishes on the .. . . . .
trays to be heated up subsequently (in situ on the trays) for serving at the appropriate time. To preserve it during the intervening period, between p~eparation and serving, the food may be kept suitably cooL by xefrigeration. Such re-heating of food rom a chllled condition to prepare it for servlng, is commonly ~eferred to a~ regeneration or rethermali2ation. Such systems may also find use in transport catering le.g. in~ h~ on aircra~t) and "meals on wheels" dlstribution service~.
Apparatus for use in one such regeneration system is described, for example, in Patent Specification US-A-4 285 391~ That apparatus comprises a rethermalizing trolley wh~ch can be stored in a refrigeration cabinet when loaded with meal trays, and wheeled out ~rom the cabinet when the meals are to be served. The trolley comprises a stack oE shelves, each aaapted to support one meal tray. E~ch shel~ comprises three flat heating elements and food dishes on the meal tray project through openings in t~ bo~tom of the tray 50 as to stand on the elements. ~ an appropriate time the heating elements are switch~d on to heat the three dishes of each tray, to regenerate ~he food in the dishes, and the trolley is aterwards wheeled out from the cabinet for service of ~he ~meal tra~s. The meal trays have insulated covers and the individual dishes can be heated up, within the cab~net, without ,: . . ; , . . ,:: .
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21/11 ' 8~ 15: ~1 ~021 456 13B8 BARRER BRETTELL ~ ~ ALEX E MACRAE C0 l~kl 004 2~3~3~i7 substantial det~im~ o ~he re~ri~erated en~ironmen~
~hich ~ai~ Lins o~her ~unhea~ed) dishes c: ool ~
LI~ ray :tox us~ in hat appara~us land AS
S i n s~m~ similar form is geher~ll the c~se in all S~IC}~
~e~n~ratio~ s~ o~he~ ~o pro~id~ a plhrall~y o:E rec~e~s~s ~ ~LccommodAte r ~ xar~ utLeryJ
corLdi~nent~ r ~n~ , an~1 also three upen-bo~:tc~m c~mpar~n~s in which th~ dishe~s ~or ho~
~4d ~rc r~irleti~ T~Ee three open ~o~t~In compart~ents are i~ registr~ ~ith t~e hea~ing ele~nts of the troltey ~hel~ i~ on~ orien~tion o~ the tra~ on the shelf, bu~ in case there ~hould be no food regen~ration neede~ for ~ p~rticular ~ray i~ is possible lor ea~h 15 tray ~o be ~hel~ed in An oppo~ite oxien~atio~ w~ic~
res~lt~ i~ the ~ea~ing elements ~or th~ s~ not bein~ a~ Ta~ed. EIowe~er, should a tray be suit~bly inserte~ for ac~lva~ion v~ ~ e he~ting elemerlts hen necessaril~ all ~hree el~men~ of tha~ shel~ will 2 0 opera~e, ~ven tho~sh there ~r b~s ~o dish in on~ or more o~ ~he open-bo~tom compartments.
A ~ystem w~ic~ af~ords greater v~r~satility~ in allowin~ for ~e~l tr~s which require some ~t no~ ~11 i~ o.~ Ltin~ elerae~ts Xor a tray ~o be ac:tivate~r is ~sc~i~ed i~ Patent ~pecifl~ation ~S~ 005 745. I~
t~at ~st~m ~le ~ea~ing el~me~ts of ~h shel~ of t~e ~rvice trolle~ can ~e s~itched on o~ o~f indi~idu~lly hy an oper~or~ ~o en~ri~g ~at o~ly those h~ ing ! 30 elements whic~ are ac~u~ need~.d ~re opera~a.
Simil~rly, i~ t~e ~stem de~ribed in Paten~
~peci~ati~n ~S-A-4 203 48~ th~ he~t~ng ~lements can be con~rolled in~ivi.~u~lly~ in ~hat cas~ ~om 2 pro~ramm~d compu~r c~n~ro} ~cility.
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21/11 ' 89 15: 32 ~P021 456 13~8 BARI~ER BRETTELL ~ ALI~Y~ ~!ACR.~E Cn C? 0~15 38~
All three o~ ~ho~e knowrl sy~t.emS ss~ allow~ ~o ~L
~reater or lesser degree r for ~ariatioll~ in the re~ul~ements :Eor hezL~in~T dish~s in the hot ~ood ~ Lpa:r:~cn~:~ of ~ y~j or ~ lc)~de~l ~rolley. q;he 5 sel::ond ~nd third sys~e~s re~rred to permit appropri~e in~ du~l ~orl~rol o~ e heating eleme:~ts, but in ~11 three cas~s an opera~or has eithe~ to inspect each tray, or be supplied ~it~ the rele~an t in~ormation a~aout ~he make-up o ~ he tray~, in order to know the 10 de~all c)~ ~e heat.ing requiremen~. In the third sy~tem r ~or exa:~ple, a printed recor~ o.~ ~e ~e~uire~en~s is prepared in order that the ~e~ermalizirlg ~:02~rol system c:omput~r can be P:~gxamm~
T~re is ~ ~y~tem de~cribed in patent spe~ a~ion uS-A-4 584 466 in ~hi~h the ~eating elernents can onLy be ~c~tiv~ted in the presenc~e o:E a dish wh~c~ ~c~u~lly re~uires heating~ This is a~hieved ~0 by providirlg the hea~ing ~lemenis in ~e base~ o~ ~e di~h ~ th~elves (s~ re~iring specially ~snstruc~ed dishes~ ~n~ using c:ondt~ ors and di~;h-enga~ing contac~ts in t.he tray ~o ~pply pow~r ~rom sup~or-t rails to such in~talled di~hes; ar~y dish ~ithout a h~ting element 2~ theref~ore remAins u~heated, re~ardles~ o -~s p~sition in khe ~ra~. ~uite ~part :Erom such a ~stem re~uiring a spe~al kirld o:l~ dish, ~e supply o~ large elec~ri~
çur~e~t~ through readil~ se~ r.onta~g, :eire~: from Ldil~; to ~ ~ray and ~hen from ~he tr~y ~o ~h~
30 dis~esr i~ likely to give trouble from sparki:rlg ~nd ~rring o:E the ~ont~c~s, ~n~ is ge~er~ll;y an ~n~e~:Lra~le arr~ n~.
It i~ ~ obj~ f the pre~nt in~ntio~ to 35 pro~i :~e improved re~malizing apparat~s o:E the ~eneral kind illu~rat~d ~y the systems ~efer~ed ~o~
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2~ 9 15:32 ~021 456 13~8 BAR~ER BR~TTELL ~ ALE~ E MACRAE CO ~ 006 ~38~7 ~he inven~ion p.ruvides, in o~e o~ it~ asp~cts~
re~erm~ ing ~pp~r~tus s~itable ~or u~ in re~e~ratins c~llled food i~ a food se~vice sy~tem in whi~h prep~red meals in~luding ~hilled ~ood~ are S a~sem~l~d in individ~al me~l ~rays and hel~ i~ the ~r~ys ~or ~ period pr~'or to rege~era~ion to prepare th~
food for ~ati~g, the appar~tus comprisin~ a plurality o~ in~ivld~ally ~ont~oll~la heating ~its ~or heating food ~s necess~ry in indi~id~l fOOa dishes wi~hin a tray, and ~ cont~l s~ste~ arrahged to ope~ate ~he he~ing ll:Dits selectively s4 as to hea~ food reguiring re~ener~tion ~ut not to heat ~ood whi~hlit i~ xequired should re~ain cool, ~hara~erised i~ ~hat for effe~in~
oper~tlon o~ those heati~ unitR only wh~h are lS as~o~i~t~d with di~h~s hol~ing food to b~ he~ted ~he c:ont:rol system is ~rranged to reflect radiated sensing signal~ o~f ~h~ dishe~ and to respo~ to ~he xe~lecte~
siynals r th~ u~e of ~oc~d di~hes whic:h are suitabl~
dis~inctive a~ be~ween ~o~ ~ood dis~s ~or holdin~ food ZO whi~h i~ ~o be heated ~ col~ food dishes for holding ~ood ~hich is ~o rem~in unheat~d ena~liny the control s~s~m to disti~g~lsh be~ween ~he hot a~d ~ol~ ~ood di~hes from dlfferen~e~ in the re~lec~ed ~i~nals~
T~ sen~ing signal~ ~y ~ infra-~ed ra~iation and, in R simple fo.r~t di~he~ for ~tai~ih~ ~ood -~o ~
h~ated ~ay ~e white or m~rked s~i~ably with a ~hite patch, and dlshes ~hi~h are ~o re~ cl ~nhe~ed bla~k or markea w~ a ~l~ck p~ch, so tha~ th~ refle~ted ~ignal~ are o:~ discernably ai:ceferen~ ~reng~h~ a~
between dif~er~ ca~gories of dish.
A ~en~or u~ ompri~ing An e~it~er and a de~ector ~:an c;on~reni~ntly ~e ~ oca~d ~dja~en~ ~o a di~h pbsition~d for h~a~ing in order to ~e:Elec~ ~L sig~ o~f s~ ~nd to pas~ an lndicatio~ o~ the ~tren~ h oE
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.-21/11~8n 15:~ ~021 4$6 13~ ~AR~ER BRETrELL ~ ALEX E ~IACRAE CO 1~007 38~7 t}~e reflect~d signal ~o the ~ontrol sy~teln lHhi~h ~o di~cern~; whe~her o~ Ilot ~he ~ood in ~h2!~ ~ish is to b~
heate~ .
S The inv~3n~iorl p:rovide~, in a~other of it~ asp~t~, x&the; :malizing apparatus suit~:e for u~e in regeher~ting chille~ food in a ihod service ~ystem i~
whiGh prep~rea meals lncludin~ ~hill~d fvods are as s~nbled in lndi~rid~al meal ~r~7s aTld held in the ~ra~s ~or ~ period prior to regen~r~L~ion to prepare the food for e~tin~ r the apparattls ~omprlsing a plurality ~f lndividu~lly ~on~rollable h~a~in~ units f~r heating ood ~s hecess~ry in individ~al food dishes within ~ray, ar~a ~ control ~ysteIn ~rrc~nyed ~o op~rate the he~ing url~ sele~ively ~o ~s to heat ood xetluirin~
reg~neration but not LO he~t food which .it i~ re~uired ~ho~d remaln ~oolt ~hara~eri~e~ in t~a~ ~h~ ~vn~rol ~ystem ~omprises ~eans whe~eb~ ~he ~mperature of ~od the di~hes in ~ ~ray can ~e moni~ore~ prior to and ~0 during regener~tlon~
T~e ~e~pe~a~ur~ o~ ~e fooa may corlvenie~tl~ l~e moni~orad indixectly by monitoring the ~empera~ur~ of dishe~ holdlng th~ ~ood i:n the tr~ys~ In a convenient ~5 arran~emen~ e~sor Uhi~ ~omprisi~g a ~er~istor or o~her te~p~rature-respon~i~e electrical ~.lemen~ is located adja~en~ ~v ~ dish positione~ ~or heating in order to ~e re$po~sive to ~h~nge~ he temper2~ure o~
the dish ~:nd to pass a ~orrespondl:ng signal to the 3 0 ~o~t~ol ~y~tem .
Mc)ni~orlng ~ :~oo~ ternp~3rature can be of ~va~tage both ir~ e3~ ri;lg ~ the ~ood is kept ullder app~vpri~e te~Lper2ture ~o~i~ion~ prio;c ~o 3S regen~r~Ltiont a3~d in con~rollin~ regene~a~io~
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oa 1~ o DARIS13R ~R~3TTnLL 777 ALr~ IACRA~ CO l~ ooo .,J
prooess for sui~le tre~en~ o:E ~he :eoc)d and e~r~y ~c~n~er~ation .
The}~e n~w ~oll~ws ~L deta.iled aes~rip tion, ~o be S rea~ with xererenc:e to the ac~ompanying drawin~, of a rood servi~e sys~em w~i~h ~llustra~e.s tha in~ention by w~y of e~ample.
n . he a~CO~rLpa~ying dra~ings~
a .,, ~i~re 1 is an o~eJ:all ~.ie~ in perspective ol a :c~t~:cmall2ing trolle~ wi th o~e of a plurality o m~al ~rR~s ~ho~L ~nstalled on a shelf o:E the ~roll~y;
Fi~re ~ is a di~grammatic pla~ o:E compa~ent~
o~ a me~l ~ray;
Fi~u;~e 3 is a ~riew in ~r~sS--~ectio~ through par~
~0 . or a mF~I f~, 6h~w;~ng A hoL ~uu~l ~$isn ln position in the ~r~y;
Fl~Lure ~ shows one ~ensor u~it of ~ kind _ . . .
utilised in con~:le~tion ~ith eat~.h nf ;;~ pltl:rAli~;y ~5 heating ele~ents of ~he ~rolley~
F~ is ~ schem~ uit d,iagram o~
~ontrol ~ircui~ry o~ ~he trolley;
Fi~ is ~ se~sor unit cir~uit dia~ram;
~ is a ~chemati~ s~ tlon o~ a sensQr 2~La~rix ~wi~c~irLg arra~geme~lt; and 3 5 F~re ~ i s a ci~cu.it dia~r~m showing in r~ore detail a matrix used to c:Qn~rol individ~al ,~ , `' .
21~ 9 15: ~3 1~021 45~ 13~8 BARKER BRETTELL ~ ALEX E MACRAE CO l~b 00 ~perati~n of he~-ting el~en~s lr~ ~ common a.c~
power s~rae~
In a ~ood serv~e system, ~or exa~ple ~or distributing lar~e ntlmhers o~ pre-prepared meal~ ~o ~he pa~i~nts in a hospit~1, use i~ made o covered me~1 ~r~ 10 i~ w~ich ~omple~e me~ls can be ~rranyed ~or ~e~vice ~d hel~ f~r a time prior to ~a~ing r and r~h*rm~lizing ~rolle~ 12 in w~i~h ~he tra~s ~a~ ~e 10 sta~k~a an~ by me~ns of w~i~h ~hilled ~o~d in the ~rays c~n be re~erated at the re~ui~e~ ~ime.
~ al~ m~y be pxepared in a sin~le ~entral ]citchen where ~lso the individuc~l meal tr~ys 10 ~re ma~e up in accord~ e witll m~nu sele~ions m~d~ by the patienks.
As illu~trated by ~i~ures 2 and 3, ~ lower ~ck 14 of each m~1 tray pro~ides an as~ortment o~ recesses 16, 18 and 20 for ~commodat~ny, respe~ively, a d~inking veRsel, ~tlery, and a ~ld~ di~h or plate ~for, ~erhaps, bread ana/or but~r, chee~e e~c.). Alsc provid~d are ~hree heating comp~tm~nts ~2, ~4 ~a 25 in which aish~s can ~e placed ~or ~ood that may ~eed regenera~in~ after ~hilling; a~ illustrated, the ~ompar~ment ~2 wo~ld be to hold a ~ain meal dish or pl~tet and the compa~L~en~s ~4 ahd 26 could be for SQUp and hot pudding, respectiv~ly. ~ow~v~, as will beco~e ~pparent hereinakte~, dishes ~c~n h~ ~la~d in ~ny of ~he he~ting co~pc~rtments 2Z, ~4 and 26 wit~ ~ood tha~
is not to ~e he~ted up be~ore ea~i~gr withPu~ ~ny ~0 ~is~d~tage ~or example, ~here may be a ~ot main cour~e dlsh in ~p æ ~men~ ~ ana a dish for ~ puddi~g t~ b~ ea~en cold ;~ ~omp æ ~men~ Z5~
i A~ ~n be ~een ~rom Fi~ure 3, each o~ the h~tin~
3S compar~n~s ~2, Z4 and ~6 (~ly ~ompax~ment Z4 is shown) h~s a botto~ wall ~onmed by ~n alumini~m heat . : ; .: : , : ~ :
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21/11 '8~ 15:3~ ~EP021 45~ l~e8 BARKER BRETTELL ~ ALE3X ~ MACRAE CO 1~1010 38~
t~ans~e~ pl~t~ ~ ~hich is retained in aIl o~e~ling th~ough th~ ~o ~om o:~ the law~r d~k 14 o~ the tr~y.
The ~r~n~:Eer pl~te 28 i~; in the :~orm of a ;Ela~ c on which a food dish ~ O ~;tands when lod~ed in the 5 ~ompar~ment 24. ~he h~ r~m ~ f;~ f tho tranc:Ec~
plate 28 is slightly abo~re ~he s~rxou~ding bottom su:~face oi~ the l~r2~r a slight rece~3 so being pro~id~d ln ~he tray :~ot~;om beneath ~he pl~te.
13ac:h ~eal tray compr:Lses also an upper deck ~2 whic:h pro~7id~s a cov~r f~or th~ loaded lower deck 14 ~
an~ each o~' the two ~eGks of ~he t~ay i~ d wifh a thermally insulating polyure~thane i~oam fillin~ 3 4 in o~der to help ~Lint~in ohilled ~ood in th~ tray at a ~uita~ly low tempexatur~. ~ox ~Ie ~n~ag~ prior to ~ng regenerat4d ~or eati~s~
Alterna~ively, at lea~t th~ low~r ae~ 14 of the t~ay may ~e ~illed with ~ so~cat~e~ h~utec~ic~ liquid~
the ~ray bei~g ~rozen before loadi~g a~d enabli~g food to be kept ~r up to ~wenty ~our hour~ in the ~x~
prlor to rege~er~ti~n.
The pr~psr~d meal ~ays, with ~ood~ th~t require 25 i~ being ~hilled in ~heir di~he~ he tr~ys, are Rta~ked on shelvçs 3~ or ~he ~er~ice ~rolley 12. In the trolley illustrated i~ Figure 1, there are eight ~helves accessible ~ro~ ~ch o oppo~i~e sides o~ ~he ~roll~y and e~h shel~ can accommo~te ~wo ~rays side-~y-side7 the ~roll~ ~hex~re c~rrie~, wh~n full, thixty-two me~l trays.
I~ ~he upper su~:i~ace o:C ea ::h shel:~ 3 6 th~re are ~;ix ~ t, di~c--l~ke, alum~niu~ heating pl~tes 3~ whi~h 3S cor~espond n size a~ po~ition with the heat t~nsfer pl~tes ~ o~ two trays 10 in~talled on the shel~ The : ` :
:~, 21/11 '89 15:34 ~ 45~ 1~68 BARRER BRETTELL ~ )~ ALEX E MACRAE CO 1~l01l Z~
~e~lng pla~es 3 8 ar2 raised ~lightly ~o~e the ~pper surfa~e o~ the chel~ in order t~ lo~a~e ln ~he ~ lar xece~ses in the bo~to~s o~ he t~ys ~ b~e~th ~he ~r~ns~er pla~es 28; ~he p~rallel hea~ing plates ~ and 5 h~a~ tran~e~ pl~es Z~ e so ,arranyed to abut f~Lce-to-~ace. 131~c~ric hea~lng el~men~s 39 ~igu~e~ 5 and 8 ) ar~ ~rranged in ~ c~on~t i or~ anner ~o~
heatins the hea~ing pl~es 3~ .o ~he h~at ~nsfer plates ~ a~d t~e ~oo~ dis~e~ 30 skanding ~n them ln 10 the t3~ys 10 Op~ra~ion of ~elec~ed hea~in~ elem~:nt~ at requi~e~
kime~ is c~n~rolled automa~ically by an elec~t~onic~
control sy~;~em o:E the ~rolle~ whlch i~clude~ ~L
micxoprocQ6so~ ord~r t~Lat the control s~s~m can know w~ h heating ~lemen~ are! re~uired to be oper~ted and c~an continually~ monitor -the ~e~npe~ u~ o:E ~he f~od ~ishes in the tra~s, ~he system lncludes ~en~or UIli~:5 40 itte!d into th~ heati~g pla~es 38 ~0 ~ indicat~d ~y Fi~ 1 ~which shows onl~ ~he 13e~Lting pl~es fo~ o~e shel~, but all the shel~:s ~Lre in f~Lc~ the ~e) eac~ he~L~iny platq 3~ h~s ~r~ openir at its centre inl:o w~ h i~s as~;~cia-~ en~r u~it 4n 25 is fitt~ed. A fl~ top su~:Eace~ o-E -the sen~o~ unit is fl~sh wi~h ~he upp~r ~ur~ac:e or th~ heat~ng pla~e.
E~ch ~nsor unit 40 ~Fi~re 4~ ~omprises ~n in~r~-red em~ter ~ infra-red det~:ctor 4~ and a 30 thermistor 46, ~he ~ee compo:~lent~ ~eing mounte~l on ~
printed c~ r ::ui~ ar~ 4 and p~t~ed to~eth~r in a ~lear s tir~g resin ~, An uppermo~ e~ge- of the thermi~t~r ~
is c::oinciden~ wi~ op ~urface o~ th~ sen~or unit so as to engage kh~ urld~rsur~ace Qf the asso~iated he~t ~S t~Lns~er plate 28 o~ ar~ inst~lled t~ay; the thermist~r i~ so inst~ ,d to ~e ele~ric~l:l.y resp~ to ~. :
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l1:11 8~15 35 ~021 45~ 13~8 BARRER BRETTELL ~- ALEX E MACRAE C0 1~012 `
~0(~13~
varia~ions in the temperature ~ tr~n$~er pl~t~
28. ~he ~hree Compo~en~s ~ ~ 44 ~n~ 4~ o~ ~he ~it ~re ~le~tri~ally interco~ec~ed hy the pxinted cir~uit bo~rd 4~ a~d three le~d~ 50, 5~ ~nd 54 .~rQm the ~o~rd provîde for common ground, inpU~ ~d ~U~pU~ co~ne~tion~
respe~ ly Wlth Xe~erenGe ~o Fi~ure 5, the ~on~rol sys~em ~omprises in addit1~ to the Inicropro~essor ~?U~ ~
real-time ~R~) clo.k which en~bles the system t~ kee.p ~ra~k o~ t~e ~ime o~ day. ~ di~it21 display and keyp~d, ~omm~ica~ing with the mic~oprooessor ~h~ou~h.
A~l interfa;:i~g chip ~PIA), ena~le c:oImnuylicatio:~ hetween the microproce~or an~ an oper~or~ ~m~r~ a~pa~ity i~
~ ia~d ~hr~ h ~.PRO~ a~d P~M ~a~ ies An analogue ~o digital conver~er (AD~) en~bles ~ol~ge signals ~rom ~he se~sor units 40 to be read by th~ CPUO A se~ond inte~a~ing chip (VIA~ link~ the CP~ to ~wo wirlng matr 1~es 5~ and ~ r c~n~ l of ~he heating elements z~nd th~ eensor units 40, :cespec:~i~ely.
q'he ma~iCes S6 ~nd 58 en~ the ~in6~y - six hea~iny elemen~s ~nd the I~ e~y~ix :~ie~sor unlts t there hei~g s.~x ~ e~ch on ea~h of ~ix~een sh~ s) ~o be controlled indiv~dually. Ea~ ma~ri~ i~ a~ 8 x 12 arra~ement ~ tw~ty di~tinct condu~iv~ pa~hs con~idered in colu~ns ~nd row~, e~ch heating elemen~ or G~n~f-r "~ in~ ~n~ a ~ 0s5 ~ unique ~om~ t~o~
o~ ~olumn ~nd row pa~n~ Lu~ ivi~ trol ~n derin~ the sens~r uni~s ~0 in the ~tr~x 5~
~irs~/ the ~welve row paths lead fxo~ ~ ~a~si~or s~chi~ devic~ 60 ~nd t~ eight column pa~hs le~d ~o a~ a~al~gue switchlng devi~ r both of which devic~s are u~d~r ~h~ ~ontrol o~ tkte VIA ~hip. Ou~ptl~ n~ls ::
1R ~IR ~n~1 a~fl 1 ~R RARRT~R RRF.TT~TT. ~ A~.FI F l~lA~'RAlZ ~n la3n1 1 2~6~33!~
11 .
xom the analogue switc~ing devl~e 6~ ~re p~ssed to the ~C ~or ~onverSio~ ~nd onward tr~nsm~sSion t~ the CPU.
~ onsidering the hea~ing ~lemen-ts in ~he matrix S~, the twelve row ~h.~ fr~m ~ 6~ ~ tW4 ~r~ ~s ~ i ght c~lumn. pi:L~h~ d to e~. b~nk ei~ht ~iac~ both ~Lks.. o~ s being urlder the ¢~nt:~ol c~:E thc ~ ~h~ p, 3~ b v4~ .y~ 0 energise the hea~ing eleme~t~, bu~ ~o prevent mains 10 ~-olt~ge reac~ing ~he ~P~, the ~r~acs are not directly ~onnected but are isolated optically ~rom the main ~ir~uitry by opto~iaCs~ To inCre~se heating elemen~
life a~d red~ce in~erf~rence, th~ ele~me~s ~re swi~h~
on ~ of~ only ~hen -~h~ mains vol-~age cy~l~ 15 at 1~ zero. The ~otal loading o~ all the-~e~in~ element~ o:E
~he tr~lley would ~e 288kwr but ~y using a pulsed pow~r sha~i~g ~cahniqu~ ~he ~xolley is ~nA~ to op~rate ~ro~ an ordinar~ 13 amp ~k~ pow~r supply.
Th~ sen~r uni~s 40 serve ~wo purposes~ As herein~ re ref~rred to t thrvugh u~e of ~he thcrm~to~s 46 th~y ~~ Le~ nal v~.riations in t~p~x~-~ure ~ the heat tr~nsfer plates 2~ and ~o (~ndir~ctly) tv monitor food temp~ture. ~owevex, ~hey ~urt.her have an essenti~l role in i~e~ti~ying whlch dishes xe~uir~ hea~ing ahd whi~h do no~ when the l-. i m~ ~ rr.~ w~ 4n.. ~ ttcr -~ UDc~ lo~ i:l effe~te~ thr~u~h u~ ln~F~ eml~ter ~ and det~c~ 44 o~ each unit.
D~ a~ CI;:L ~2~3 h215 ln lt: a small ape~u~ 68 (~igure 3) W~ich is ~o ~iligned with ~he ~nso~ u~t 40 o~ ~he ~ iate~ he~tins plate 38, whe~
the ~ray i~ i~istalled on ~ ~rolley shelf 36 t th~t it 3S ~ms a window above the inrra-red elem~n-~s 42 and 44 ~ the Uriit. ThR sen~or U~lit 40 ~an 60 ~view" the .i,, ~ .
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15: 3~ ~021 45~ S BARKER BRETTELL ~ ALEX E MACR~E C0 1~ 014 38~i~
bott~m o~ Any ~ood ~ish 30 in the heati~ compartment 24 o~ the t~ay hy r~;lh~in~ An 1n~ r~ si~nRl ~ff the ~ish :by mea}ls of it~ in~ red ~lemen-t~ 42 ~Lnd 4~.
~ The the~mis~or 4~ i~; p~ ioned asi,d~ from the window 5 68, so as ;~ o enga~e the und~ide of l:~e ~eat t:cansler pla~ Z8 ~ ~ Each or ~e ~oo~ di~hes 30 used in ~he c:~mpar~men~s ~ o~ the ~ray is iclenti~ied as one to ~e he~te~ or not, ~s the c:~se may be y by means of whi~e or a black ~:respec ti~ely) ider~ yir~ patch ~n lo its ~ om su~face oppo~i~e the winc~ow 68 ~he ~cfl~c~d ~:igrlal whiah ~::: in:Fr~ cc~ ~ctcc~ r ~ oi~ cn ~ct;ivated sensox uni~ ~c~ives :~rom a di~h with ~ whi~e marki~g is of a markedl~ ~lif~e~ent le~reL i~rom that which w~uld h~. r~ rP~ fr~m ~ h .w~ ~h ~ hlA~k 15 ma;:king (or ~si~il~rly in the a~senc:e G:E a di~h from the ;:ompartment) and the OUtp~lt signal rrom ~he sensor unit 40 ~ ~ whole i5 con~equ~n-~.ly n~ e ~if~erent order ;Ln ~he ~wo ~a~;es. Ac~ordin~ly, provided that in prepara~ion of th~ meal tx~ys ~ishes with whi~e 20 mRrkings are tlsed to con~airl ~h~se f~d~ ~Thlch need to ~e :~g.c~c -~ted,~ ~ibllc~b w1LlL IJla~ e~ ,y~
con~in ~hose roods which do r~o~, the~ con~rol syst:em is ~c~le to ~e~e:~mine au~oma~ically whlc:~ he~ti~g elemel:Lts ~eed to be ~perate!d }~y dlstinguishin~ be~wee2~ the two 25 level~ ~f signal~ ~ein~ produ~ed by the sensor ~ s 4~.
Power for ~he control sys~em comes prin~ipally f~om an i~ternal r~h~ge~ble batter~, mains power ~ei~g re~ulrea only ~r ~he heating ~leme~ts ~uring ~ood regener~tion~ d~in~ which ~ime the b~ttery can also ~e ~ha~ed.
~ he system i~ u~de~ ~he ~on~ro~ of a pxogr~n ~to~ed in ~h~ ~P~, whiGh pro~r~m can be ~han~ed....to ~5 vary ~r up~ate the system ~hen re5uir~d, ~o~ ex~mpl~ to ~eet statu~ory re~u~tions ~or ~he sa~ s~o~ge, . :
22~11 '89 15:31 ~21 45~ 1368 BARKl~R BRETT~LL ~ BIACRA~ l~boo3 2~q~3~1~i7 handling and regeneration of chilled meal~. When t~
system is first powered up, the program set~ all the hardwate to a predetermined set o~ conditions. Once this is done the program sta~s in a loop constan~ly reading the keypad to check ~or any input by the operator, and checking whether the time has been reached fox regeneration; i an input is detectea the program will branch off from the mai~ loop ~o perfoxm . the required task.
Every two minutes the program jumps out of the main loop in order to activate and read the ~ensors 40 (one by one) and so monitor the arxangement of food dishes 30 and their temperatures~ ~his information is recorded by the CPU in the memory. ~he CPU is ~hereafter able to detect any change in the arrangement and temperature of the food dishes b~ comparing the new information each ~ime with that previously recorded~ One minute before it is time to reqenerate, the program branches off to make a last check o~ the food dishe~ prior to regeneration, and if all is satisfactor~ the program then ~xanches o~ into a regeneration routine.
Continual monitoring of the food dish temperatures prior to regenerat.ion can be important, as it may be es~ential that the temperature of chilled ~ood held in the trays does not rise above, sa~, 10C. .Should the control ~ystem detect that such 2 ~ rise i~ temperature has occurred it will cause an aLarm signal to be given together with an indication ~o tlle operator as to which dish is a~fected.
During thei regeneration routine, the system continually activates each Gf the required hea~ing element~ in turn, also continually monitorin~ the : , ' : . :: '~
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9.1~P.KE~R BRI~TTELL > ~ L~
2 1 ,~ 1 1 ' 8 ~ 3 7 ~O
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;2~)1~3~,7 tempera~u:::es o~ ths dishes. Tow~rd~ the end o the ~ou~:~.ne, ~e he~L~ing elesne~; ass~ciated wi~h di~he~
whi~h ha~e alrea~y rea~hed their resuir ~l temp~ratu:re are acti~ated by ~e control ~ys~em ~nly a~ much a~ m~
5 he require~ ~o m~intain ~ha~ npera.~u~e..
This ~oOa se~i~e systeTn so I t~kes a~caun~ c~
~ra~ing load~ o~ m~ ompone~ts to en~le ~he ~ Pm -~o use a ~lni~u~rL o~ ene3~y ~luring regeneration.
~egardl~ss of ~he type o~ food ~ein~ reg~nera~a th~
~ n~ ~pC~3~ r ~ ne neated ~oo~ ~omp~rt~e~ts will be ~ub~t~ially ~he s~me.
Inst~ad o~ indi~idual progra~mi~g o~ troliey~ by keypa~s o~ ~ach, ~olle~tiv~ pro~x~mmin~ by an inra-red or ~he~ tr~n~mit~e~ could o~ cour~ b~ employed~
Further di~Gussion o the operatio~ o~ ~h~ s~nsor u~i~s now ~ollows~ Figure ~ i8 a ~ir~uit diagr~ru-~ r a ~n ~ na~l- u.ll~, wn~ o~sider~d as ~wo varia~le re~is~ors forming a potenti~ divider, the two ~ari~ble resi~tors bein~ ~ormed by th~ in~ra-re~
det~ctor 44 and ~he thermisi:or ~ As ~ whol~ u~it, ~he~ sen~or ~an b~ consi~ered a~ a de~ic~ ~t pro~uce~
Z~ an output vol~age tha~ is rela~ed to its ~e~pera~ur~
~d. po~ltion ~ ive ~o a re~lec~i~re sur~ace, 1. e . t~
bottom ~ur:~ace of ~he dish ~0..
~he ~io~e 1 is inGluded ~o prevent ~h~
30 i~te~action of ~h~r ~nsors ~ Lll~ ma~rix, ~ cau ing the signals ~ low in ~ne di~ection or~ly.
As he~einbe~ore described and shown also in Fiqur~
he ~en~or units 40 ~r~ con~e~te~ ~;o a~ ~o or~ a 35 matrix. Th~ ri~ cor~ ts or ~welve powe~ ~upply li ne~ (the row p~3 ~ach ~ne being con~rolled by the , . ~ -, -; ' .: , ,. '; , "' , , :
22/11 '89 15:32 ~021 456 1368 BARKER BRl~VrELL ~ MACRAE l~boo4 zoo3a~
transistor switching device ~0, and eight signal lines ~the column paths) connected to the analogue switching device 62. The analogue switch routes the signal on one o~ the eight signal lines to the analogue to digital converter (A~C~. Exactly which signal lina i.s selec~ed depends on a binary num~er from 0 - 7 belng sent to the analogue swi~ch hy the CPU.
. , In order ~or the value of a particular sensor unit to be reaa, the CPU must ~lrst s~itch on the transistor that powers the sensor unit in questlon through the correspon~ing power supply line, an~ then send the required binary value to the analoyue switch to connect the output signal from the sensor unit, on the coxrespond~ng ~ignal line, to the analogue to digital convertex; although there are eleven other sensor outputs connected to this signal line, they are all switched off leaving only the signal from the sensor unit in question to be present. ~hese two opera~ions ~0 actually happen simultaneou~ly with the CPU sending a slngle binary value to the VIA that controls the ~ensor matrix.
!
It can be seeIl ~rom this that only one sensor may be read at a time~ To increase the accuracy, each sensor is actually read sixty-four times and an average taken~ .
The output ~rom each sensor unit gO, once read by the CPU, is a numerical value ~etween 0 and 255. This value is a representation of the type and temperature o~ the dish 30 with which the sensor is associated.
Initially~ he~ore the trolley is loaded, all sensor units will return a low value ~e.g. 20) there being slight variations between the ninety-six : ~
:.
21/11 '8~ 15:38 '~021 45~ 1388 BARKER BRETT13LL ~ ALEX E IIACRAE C0 l~bO18 20 [)~3fi~
1~
re~dln~s. ~y ~lue v~ Li;Eferen~ ,~rom ~he re~t would ~n~icate ~ha~ a problem e~ists, an o~jec~ obscuring ~he s~n~or ~or ~x2~npl~ r an~i a wa~ing :bu~er would be soun~ed to al~t t~e operator.
Once ~e ~rolle~ is lvaded and ~he ~ensox~ ~ave been x~d, all ~he val~e~ should have d~opp~d ~tle to the lower t~nlpera ure o~ ~he dis~ , wheth~r r~3~uiring h~;~tin~ ~- no~r O~ ~udl~le~ e same if n~ pla~e i9 la present; ~ensor ~nits ~sso~iated with dishe~ ~hat requixe hea~ing, h~vi~ white pa~che viewea by the sen~or ~its, w~ 11 re~ur~ a ~Talue ra~he~ lower th~n those t~a~ are ~o r~aln cold ~i . e O -kho~e ~aving ~la~k patGhes). A~y rise in valtla (i.e. w~en ~the ~rolley i~
fir~ Loaded) ~ould indl~te ~ p~zte o~ ~oo hi~h a temperature, ~ke op~a~or bein~ ~arned should thi~ be 'th~ CA :EI E~ .
S~sequ~nt rea~ing~, ~et~een t~e ~lmes of loaaing ~d regen~ration r will ~how a gra~al i~creas~ in v~lues ~ the ~e~perature ~f the food on the ~ish~s ri~e~ ~o~ar~ e ~mhie~t ~e~perature, ~his be~n~
~low~d b~ ~he inB~la~ed tray. A wildly differen~ ~lue ;Ero~ t~ ree~ would point towards ~ prvble~ wi~h t~e 25 t~a~r ~uch a~ ~n ~mproperly locat~d l~d reducing t~e ~mot~n~ of insu~ion 2nd cAtl~ing the gre~te.~ in~rea~
in te~pe~ture~ ~
From ~h~a readi~gs }~far~ the ~olley was loaded 30 I:he CPU i~ al~le t~ ~al~ulate 2L ~ralue ~at ~o~re~ponds to the 10 c: l~mit ~at the . ao~ mu~t remain belc~w ~efQre regener~ionO Ea~h se!nsor xeading is compaxed with thi~ vallle ~nd warning ~i~7en sh~u~d ~ny ex~eed i~.
3~ Du~ing re~ er~t~on ~e r~2dings ~ill rise f~i~ly ;~pi~ly ~l~ e food temper2Lture. Rea~ing~ a~e n~w . i ' ~ ' . -- ' ~ "''`............ "' ''':.:, Zl~llsa 15:38 ~021 45~ 13~8 BARRER BRETTELL ~ ALEX E ~IACRAE CO ~ 01~
2~38~
oompa e~ed with a~o~her predetermL:Lned v~ e that indic~tes the 70C t~at th~ :~oo~ m~s~ reach to be prop(2rly r~gener~ted.
The ~P~ i s Able to ~ e~e~riate ~etwee~ :Evod pro~iuc~t~ gre~tly ~ erent Ele~ c~p~ities b~ ~heir t~mpe~ ure readi~g~ during re~erlexatio~ nd regu7 at~s th~ amoull~ o~ hea~ing ~iv~ to each dis~ accordin~ly in ox~er lo c~mplete the regenera~iorl of alL the ~eals at tihe saune tim~. ~ow~er, ln praciice mos~ food produc~
re~ the ~ame ~moun~ of he~ing and lit~le such ~ervention by th~ CP~ g~n~rally ~ccur~.
m~ aetailed dascription now ~OllO~ wi~h ~5 ~e;ee3:en~e to Flgu~e ~, o t:~he c:ontrol m~Ltri}c 5~ for t.~e heat.ihg elem~n~ 39.
~he twelY~ row pa~hs a ~o 1 lead to ~h~ ba~};
6~ a:E t~el~ xiac~ ~na ~h~3 eiyh~ ~ol~unn paths ~ to lI
~a lead :~rom ~he :4ank 6~ c~f ~ight ~riacs . I!Iains a~ ~.
~ol~a~ applied to the m~trix ~roug~ the tri~c ban~c~ . The p~r~icllla:~ heatlng el~ment 3 ~ indi~ate~ in wing ~11, for example, ba actlva ted onl~ by t~e m~rix com~inatic)rL Ce~
~5 y Ine~s ~ ~u~ a ma~r~ a p:rim~Ly ~ondu~t~e pa~h ~r~u~h ~ J;;irlgle ~lement i~ c:reated b~
~ny ~ele~ted c;:ombina~ion o~ single ~ol~n ~Ld r~w paths, a plurali~y oi~ ~ec~ondary condtlc~iv~ paths are pc)tentially ~eated throu~h combinations of elements in ~eries ., ~rhis would result ~ ~ power wast~ge / and some heating vf elements which~ a~e in~ended ~o remairl nac~ive, urll~ss me~s~l~e~ are ta}cen t~ block all ~uch ~c~nd~Lcy pat~ks.
- ~ .: :,. , , . ;: : ~
::~ , : ;.. : -~~ ~021 4S~ 13B8 BARI~ER BRETTELL -~) AL~{ E ~IACRAE (~0 ~102~
1~ ~
By me~n~ o~ ~ pair o.~ oppositely o~ien~ed divdes 70 an~ 7~ at t~e ~.c.. irlput of the tria¢ ~ k 66 at the he~d q~ the ~olumn path~ A ~o ~, ~h~ mai~ aurrent ls split into it9 negative and positiv,~ comp~nen~. One S compone~ supplies the fo~r p~-~hs ~ to D and the o~h~
compo~en~ ~upplies the p~ths to ~ Each of kh~
~ran~er pa~h~, b~ween a row an~ c~lum~ r l~clu~e~ a diode 7~ whi~h is orie~t~ed appr~pxiately t~ ma~h th~
pol~ri~y o~ the column pa~h to which i~ is ~o~n~cte~
10 A11 ~l.re o~ t bo f~n~r ~ 5 ~onnec~d ~o oach o~
~he column~ A ~o ~ are there~ore un~direc~ional i~ fhe s~ ense. Sin~ ~e ~x~iqtion o:C d con~lv~ h r~qul~ on~ ~-E ~w~ ~.rans:Ee~ Paths co~ec~ed ta the ~me ~olum~ pa~h r ~n~ one o two tra~er pa~h~ ~onne~ed t~ ~he sam~ row p~h, to b~ a reverse curr~nt path, ~locking o~ all such secondary E~t~ Lc:hlev~
~0 . , .:~ -; .
, ,, . . ~ . .
, ~ :~ ,' ., ;
Claims (9)
1. Rethermalizing apparatus suitable for use in regenerating chilled food in a food service system in which prepared meals including chilled foods are assembled in individual meal trays and held in the trays for a period prior to regeneration to prepare the food for eating, the apparatus comprising a plurality of individually controllable heating units for heating food as necessary in individual food dishes within a tray, and a control system arranged to operate the heating units selectively so as to heat food requiring regeneration but not to heat food which it is required should remain cool, characterised in that for effecting operation of those heating units only which are associated with dishes holding food to be heated the control system is arranged to reflect radiated sensing signals off the dishes and to respond to the reflected signals, the use of food dishes which are suitably distinctive as between hot food dishes for holding food which is to be heated and cold food dishes for holding food which is to remain unheated enabling the control system to distinguish between the hot and cold food dishes from differences in the reflected signals.
2. Apparatus according to claim 1 characterised in that the sensing signals are of infra-red radiation, such that reflected signals of discernably different strengths can be obtained from dishes with white and black colouration respectively.
3. Apparatus according to claim 1 characterised in that it comprises a plurality of shelves on which trays can be lodged, each shelf comprising a plurality of heating elements which are arranged to be in registry with the dishes in a tray installed on the shelf in order to heat those dishes if required.
4. Apparatus according to claim 1 characterised in that the control system comprises means whereby the temperature of food in the dishes in a tray can be monitored.
5. Apparatus according to claim 4 characterised in that the temperature monitoring means comprises sensors arranged to be responsive to variations in temperature of the dishes in a tray.
6. Apparatus according to claim 5 characterised in that the sensors comprise thermistors.
7. Apparatus according to claim 5 characterised in that the effects of a particular dish in a tray on the temperature sensor and on the radiated sensing signal are combined to produce a single operating signal for the control system.
8. Rethermalizing apparatus suitable for use in regenerating chilled food in a food service system in which prepared meals including chilled foods are assembled in individual meal trays and held in the trays for a period prior to regeneration to prepare the food for eating, the apparatus comprising a plurality of individually controllable heating units for heating food as necessary in individual food dishes within a tray, and a control system arranged to operate the heating units selectively so as to heat food requiring regeneration but not to heat food which it is required should remain cool, characterised in that the control system comprises means whereby the temperature of food in the dishes in a tray can be monitored prior to and during regeneration.
9. Apparatus for use in the controlled heating of materials in dishes or other containers, the apparatus comprising a plurality of individually controllable heating units for heating materials in the dishes as necessary, and a control system arranged to operate the heating units selectively characterised in that the control system is arranged to reflect radiated sensing signals off the the dishes and to respond to the reflected signals, the use of dishes which are suitably distinctive as between those for holding materials which are to be heated and those for holding materials which are to remain unheated, or as between those for holding materials which are to be heated to different degrees, enabling the control system to distinguish between the categories of dish from differences in the reflected signals.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB888827611A GB8827611D0 (en) | 1988-11-25 | 1988-11-25 | Food service system |
| GB8827611.8 | 1988-11-25 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2003867A1 true CA2003867A1 (en) | 1990-05-25 |
Family
ID=10647492
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002003867A Abandoned CA2003867A1 (en) | 1988-11-25 | 1989-11-24 | Food service system |
Country Status (8)
| Country | Link |
|---|---|
| US (2) | US5243171A (en) |
| EP (1) | EP0445189B1 (en) |
| AU (1) | AU636862B2 (en) |
| CA (1) | CA2003867A1 (en) |
| DE (1) | DE68922861T2 (en) |
| GB (1) | GB8827611D0 (en) |
| WO (1) | WO1990006075A1 (en) |
| ZA (1) | ZA898952B (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5274216A (en) * | 1989-08-15 | 1993-12-28 | Aladdin Synergetics, Inc. | Food rethermalizing and satelliting tray |
| EP0487560A1 (en) * | 1989-08-15 | 1992-06-03 | Aladdin Synergetics, Inc. | Food service system and method of rethermalizing food |
| WO1994000044A1 (en) * | 1992-06-19 | 1994-01-06 | Josef Draxl | Electrically heatable tableware and receptacle therefor |
| US5797445A (en) * | 1992-11-23 | 1998-08-25 | Standex International Corporation | Refrigerated rethermalization cart |
| US5868195A (en) * | 1992-11-23 | 1999-02-09 | Standex International Corporation | Rethermalization system |
| GB2284905B (en) * | 1993-12-15 | 1998-04-01 | Burlodge Ltd | Food regeneration |
| US5603858A (en) * | 1995-06-02 | 1997-02-18 | Aladdin Synergetics, Inc. | Heat retentive server for induction heating |
| FR2737638B1 (en) * | 1995-08-03 | 1997-10-03 | Bourgeois Prod Coop | INDUCTION TRAY HEATING DEVICE |
| ES2193270T3 (en) * | 1995-11-21 | 2003-11-01 | Electrolux Ab | SURFACE FOR COOKING WITH CONTROL DEVICES. |
| ES2115525B1 (en) * | 1996-03-20 | 1999-02-16 | Lato Ventura Vale | SYSTEM OF USE OF THE TOTAL SURFACE OF VITROCERAMICA FOR KITCHEN. |
| US5948301A (en) * | 1997-01-31 | 1999-09-07 | Bel Group Llc | Food thermalization device |
| US6265695B1 (en) | 1997-01-31 | 2001-07-24 | Benno Liebermann | Food thermalization device and method |
| US5969316A (en) * | 1997-10-22 | 1999-10-19 | Cybermark Llc | Smart card for offline automated meal plans |
| US6034355A (en) * | 1998-06-08 | 2000-03-07 | A La Cart, Inc. | Meal delivery system |
| FR2809480A1 (en) * | 2000-05-24 | 2001-11-30 | Seb Sa | APPARATUS FOR HEATING A FLUID SUCH AS IN PARTICULAR THE EPILATORY WAX |
| FR2811526B1 (en) | 2000-07-11 | 2002-10-11 | Production De L Aube Soc Ind D | MEAL TRAY DISTRIBUTION TROLLEY WITH INFORMATION PLATE |
| US6344630B1 (en) * | 2000-10-25 | 2002-02-05 | Cambro Manufacturing Company | Thermoelectric heated food service cart |
| IT1319292B1 (en) * | 2000-11-08 | 2003-10-10 | Whirlpool Co | DEVICE TO DETECT THE PLACEMENT OF COOKING TOOLS ON A COOKING HOB WITH DISCRETE AND DISTRIBUTED HEATING ELEMENTS. |
| ATE261694T1 (en) | 2001-05-17 | 2004-04-15 | Tecnhos S R L | DEVICE FOR DELIVERING MEALS AT AN APPROPRIATE TEMPERATURE, ESPECIALLY FOR USE IN HOSPITALS |
| ES2567796T3 (en) * | 2001-10-12 | 2016-04-26 | Whirlpool Corporation | Cooktop with distributed discrete heating elements |
| US6693262B2 (en) * | 2001-10-17 | 2004-02-17 | Whirlpool Corporation | Cooking hob with discrete distributed heating elements |
| ES2284322B1 (en) * | 2005-04-25 | 2008-09-01 | Ildefonso Orozco Espinosa | MULTIZONAL VITROCERAMICS BY INDUCTION, WITH AUTOMATIC AND ADJUSTED ACTIVATION OF THE OPERATING AREA. |
| US20090096617A1 (en) * | 2007-10-10 | 2009-04-16 | Multiteria, Llc | System and method for monitoring food temperature in food service equipment |
| JP2010153730A (en) * | 2008-12-26 | 2010-07-08 | Omron Corp | Wiring structure, heater driving device, measuring device, and control system |
| JP5062272B2 (en) * | 2010-03-11 | 2012-10-31 | オムロン株式会社 | Temperature control system |
| DE102012102575B4 (en) * | 2012-03-26 | 2024-04-18 | Hupfer Metallwerke Gmbh & Co. Kg | Method and induction device module for heating food |
| ES2389533B1 (en) * | 2012-04-18 | 2013-09-02 | Serhs Food Area S L | Control and management system for collective restoration and associated procedure |
| US11666160B2 (en) | 2017-08-24 | 2023-06-06 | Unified Brands, Inc. | Method for temperature monitoring and regulation and systems therefor |
| US11191370B2 (en) | 2017-08-24 | 2021-12-07 | Unified Brands, Inc. | Temperature monitoring and control system |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1679068A1 (en) * | 1966-12-15 | 1971-10-07 | Jean Le Boulbouech | Electric heater for packaged food |
| US3842724A (en) * | 1972-09-27 | 1974-10-22 | A Korr | Apparatus and package for use in heating or cooking of food by electrical conduction through the food |
| US3924100A (en) * | 1974-05-09 | 1975-12-02 | Anthony C Mack | Mobile food serving system |
| US4005745A (en) * | 1974-09-30 | 1977-02-01 | Anchor Hocking Corporation | Apparatus for storing, refrigerating and heating food items |
| US3974358A (en) * | 1975-01-10 | 1976-08-10 | Teckton, Inc. | Portable food heating device |
| US4020310A (en) * | 1975-03-20 | 1977-04-26 | Souder Jr James J | Container for inductively heating food |
| US4110587A (en) * | 1975-03-20 | 1978-08-29 | Patents Licensing International, Ltd. | Method and apparatus for heating food |
| US4093041A (en) * | 1976-04-19 | 1978-06-06 | Sweetheart Plastics, Inc. | Food serving system |
| AU521969B2 (en) * | 1977-01-11 | 1982-05-13 | Anchor Hocking Corporation | Food preparation apparatus & process |
| CA1137592A (en) * | 1978-01-09 | 1982-12-14 | Robert A. Phillips | Food serving system |
| US4285391A (en) * | 1979-08-29 | 1981-08-25 | Aladdin Industries, Incorporated | Electrical system for food service devices |
| GB2131989B (en) * | 1982-11-10 | 1986-09-17 | United Glass Plc | Apparatus for identifying production codes on articles |
| DE3341234C1 (en) * | 1983-11-15 | 1985-05-15 | Kurt Wolf & Co Kg, 7547 Wildbad | Arrangement for measuring the temperature in a heating system consisting of a hot plate and a saucepan |
| US4584466A (en) * | 1985-01-02 | 1986-04-22 | Mola Manny L De | Food service system |
| CH667149A5 (en) * | 1985-04-29 | 1988-09-15 | Berndorf Luzern Ag | PROCESS FOR REHEATING FOOD. |
| DE3619762A1 (en) * | 1986-06-12 | 1987-12-23 | Licentia Gmbh | Pan recognition device |
| JPH0781715B2 (en) * | 1986-12-17 | 1995-09-06 | 松下電器産業株式会社 | Heating device |
| US5189281A (en) * | 1989-08-15 | 1993-02-23 | Aladdin Synergetics, Inc. | Rethermalization cart indicator system |
| US5093556A (en) * | 1990-02-16 | 1992-03-03 | Therma-Chill, Inc. | Rethermalization cart assembly |
-
1988
- 1988-11-25 GB GB888827611A patent/GB8827611D0/en active Pending
-
1989
- 1989-11-23 AU AU46363/89A patent/AU636862B2/en not_active Ceased
- 1989-11-23 ZA ZA898952A patent/ZA898952B/en unknown
- 1989-11-23 WO PCT/GB1989/001400 patent/WO1990006075A1/en active IP Right Grant
- 1989-11-23 DE DE68922861T patent/DE68922861T2/en not_active Expired - Fee Related
- 1989-11-23 EP EP89913231A patent/EP0445189B1/en not_active Expired - Lifetime
- 1989-11-24 CA CA002003867A patent/CA2003867A1/en not_active Abandoned
-
1991
- 1991-05-23 US US07/705,003 patent/US5243171A/en not_active Ceased
-
1994
- 1994-11-23 US US08/344,366 patent/USRE35056E/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| USRE35056E (en) | 1995-10-10 |
| DE68922861T2 (en) | 1995-12-07 |
| WO1990006075A1 (en) | 1990-06-14 |
| EP0445189B1 (en) | 1995-05-24 |
| US5243171A (en) | 1993-09-07 |
| EP0445189A1 (en) | 1991-09-11 |
| ZA898952B (en) | 1990-08-29 |
| AU636862B2 (en) | 1993-05-13 |
| GB8827611D0 (en) | 1988-12-29 |
| DE68922861D1 (en) | 1995-06-29 |
| AU4636389A (en) | 1990-06-26 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |