CA1316756C - Thermal head supporting means for a thermal printing system - Google Patents
Thermal head supporting means for a thermal printing systemInfo
- Publication number
- CA1316756C CA1316756C CA000612899A CA612899A CA1316756C CA 1316756 C CA1316756 C CA 1316756C CA 000612899 A CA000612899 A CA 000612899A CA 612899 A CA612899 A CA 612899A CA 1316756 C CA1316756 C CA 1316756C
- Authority
- CA
- Canada
- Prior art keywords
- thermal head
- thermal
- platen roller
- head
- shaft
- 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.)
- Expired - Fee Related
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J25/00—Actions or mechanisms not otherwise provided for
- B41J25/304—Bodily-movable mechanisms for print heads or carriages movable towards or from paper surface
- B41J25/312—Bodily-movable mechanisms for print heads or carriages movable towards or from paper surface with print pressure adjustment mechanisms, e.g. pressure-on-the paper mechanisms
Abstract
ABSTRACT OF THE DISCLOSURE
Each of the parts or components constitutes the thermal head supporting means is designed to be small in size,thin thickness and having such a shape as can be readily fabri-cated by press forming of metal sheet or by moulding plastic material,in addition,the thermal head supporting means as a sub-assembly is attached to the the central part of the rotary shaft so that it can be supportedin a manner of one point central support type suspension.
Depression of the thermal head utilizing this suppor-tinag means against a platen roller is performed by urging.
relying on cam action,a thermal head urging lever having a length considerably shorter in axial direction and very light weight,thereby the depression can be applied to the platen of a thermal printing system via a depression spring disposed at the central part of the thermal head supporting means and normal to the aforesaid rotary shaft and in a central support type manner.
Each of the parts or components constitutes the thermal head supporting means is designed to be small in size,thin thickness and having such a shape as can be readily fabri-cated by press forming of metal sheet or by moulding plastic material,in addition,the thermal head supporting means as a sub-assembly is attached to the the central part of the rotary shaft so that it can be supportedin a manner of one point central support type suspension.
Depression of the thermal head utilizing this suppor-tinag means against a platen roller is performed by urging.
relying on cam action,a thermal head urging lever having a length considerably shorter in axial direction and very light weight,thereby the depression can be applied to the platen of a thermal printing system via a depression spring disposed at the central part of the thermal head supporting means and normal to the aforesaid rotary shaft and in a central support type manner.
Description
1 31 675`' SPECIFICATION
THERMAL HEAD SUPPORTING MEANS FOR
A THERMAL PRINTING SYSTEM
BACKGROUND OF THE INVENTION
1.Field of the Invention:
The Present invention relates to a thermal Printins system,and more Particularly>to a thermal head suPportins means for a thermal Printins system,havins features of lisht weisht~flexibility~ready for adiustment and is esPecially suitable for an oPen-frame tYpe thermal Printins sYstem~
namely,such one the frame of which is seParated into two Pieces of an uPper frame and a lower frame,and the former is hinged onto the latter so as to be swinsablY movable uPward and downward and,further,suPerior in accuracY of Printins.
THERMAL HEAD SUPPORTING MEANS FOR
A THERMAL PRINTING SYSTEM
BACKGROUND OF THE INVENTION
1.Field of the Invention:
The Present invention relates to a thermal Printins system,and more Particularly>to a thermal head suPportins means for a thermal Printins system,havins features of lisht weisht~flexibility~ready for adiustment and is esPecially suitable for an oPen-frame tYpe thermal Printins sYstem~
namely,such one the frame of which is seParated into two Pieces of an uPper frame and a lower frame,and the former is hinged onto the latter so as to be swinsablY movable uPward and downward and,further,suPerior in accuracY of Printins.
2~DescriPtion of the Prior Art:
A thermal Printins sYstem~senerally~functions to Print alphanumeric and or image information on a Paper sheet bY
melting thermalY fusible ink aPplied on the surface of a thermal Printing ribbon or ribbons~by means of Passing both a Paper sheet and thermal Printins ribbon being overlaPped~
through a gaP between a thermal head and a Platen roller,and it has various features such as small size,light weight Yet allowing multi-colour Printins in a quite a simPle way.
In order to make the densitY of the Printed letters or images more uniform and to imProve the cleanliness bY using a thermal Printins sYstem of this kind,it is very imPortant 13167,i') to satisfY following two requirements,that is,to make a deP-resslon force between a thermal head and a matins Platen roller in the direction transverse to the width of Paper sheet more uniform,and at the same time to PerfectlY align the axis line of the Platen with the location of each of the heatins elements in the thermal head.
Because of this.it has been re~uired for most thermal Printing sYstem to adiust their dePression force in the transverse direction as uniform as Possible bY means of an adiusting screw or screws.while to alisn the axis line of the Platen roller with each heatins element relYins on the dimensional accuracY of the related Parts or comPonent Fig.1 is a side view showing the structural feature of the thermal head suPportins means of a conventional general tYpe thermal Printins system.
In the drawing,a thermal head 50 held bY a head holder 31 is dePressed on a Platen 21,and a thermal Printins Paper and a Printins ribbon being overlaPped with each other are Passed through the gaP between these two members and further fed uPward bY the Platen roller 21.
The head holder 31 is disPosed around a head holder shaft 31a rotatablY received bY the same frame carrYing said Platen roller 21 and is Pulled rightward bY a dePression sPrins 7 so that the thermal head 50 can be dePressed uPon the Platen roller 21.
The extent of the dePression force mentioned above can be adjusted bY an adjustment screw 37 disPosed on both sides of the head holder 31 so as to be uniform in the direction 1 31 675;
transverse to the direction of the PaPer sheet 5.
In the drawing,numeral 38 denotes a sensor for detec-ting the Position of a Printing ribbon 4,numeral 39 denotes a sensor holder,similarly,numeral 37'is a locking screw for fixins the adjustment screw 37 and 41 denotes a heat sink for radiating hea~ given from the thermal head 50.
However,there found following defects in the aforesaid conventional thermal head suPportins means,that is:
1~ Adiustment is required to maintain the dePression force uniform between the thermal head and Platen roller.
2) The construction of the suPportins means inevitably becomes comPlicated due to such adjustment means.
In order to obviate such drawbacks as exPlained above, the inventors of the Present invention Proposed a Prior invention directed to a suPportins means for a thermal head which enables the maintaining of a uniform depression force between a thermal head and a Platen roller,and filed a Patent aPplica tiontJapanese Patent APplication No.Sho 60(1985~-156~6, Pu~lished as JaPanese Patent Laid-OPen(Un-examined) Publi-cation No.Sho 62(1987)-611670].
Fig.2 is a schematic side view showing the main Portion of the above-mentioned thermal head suPporting means,wherein a rolled Paper sheet 5 payed out from a roller Rl is fed via a roller R2 onto the outer PeriPhery of a Platen roller ~1 and then fed leftward by turning back along the outer Peri-phery of the Platen roller 21.
On the other hand,an ink ribbon 4 aPplied with therma-lly fusible Printing ink is also payed out from a roller R3 131675 `
and overlaPped with the Paper sheet 5 on the outer Periphery o~ the Pl~ten roller 21 and then taken uP bY a take-uP
roller 39.
The thermal head suPPortins means as exPlained above and shown in Fig.3A and 3B is comPosed o~ following three main comPonents~:
1).a hinge shaft 40 disPosed bY ~ransverselY Passins through both outer side frames 30a and 30b and Placed in ParaIlel with the Platen roller 21, 2).a head holder 31 fitted around the outer Periphery of the Platen roller 21 through a rolling bearing 35 and is PoSitioned halfway between the hinge shaft 40 and the PIaten roller 21 and holds a thermal head 50 at the side confron-ting with the Platen roller 21,and 3).a Pair of coil sPrinss 7a and 7b attached at both axial ends of the head holder 31 so as to resilientlY urge the head holder 31 against the shaft of the Platen wheel 21.
Having a construction as explained above, the head holder 31 can be swung in a see-saw like motion around the hinge shaft 40 via the rolling hearings 35.
In addition,the dePression force exerted between the Platen roller 21 and the thermal head can be made uniform over the entire width of the printing PaPer~and bY virtue of this Prior tYpe thermal head suPportins means,an entirelY
uniform dePression force can be assured between the thermal head and the Platen roller with no Particular adjustment.
It is to be noted,however,that the head holder 31 of the prior invention consists of, 1 31 675., 1) a frame mem~er 32 ~lavirlg its transverse wldth almost the same as that of the outer frames 30a and 30b and its confisuration like a squared U shape seen in plan view, and 2) a suPPorting member ~3 carrYing a ball bearins 35 on the oPened face side.
Both side walls 32a.32b and a transverse connecting bar 32c of the frame member 32 are jntegrally formed bY such means as aluminum alloY die castins technique or the like, and these members themselves have a considerable volume tosether with a heavy weig~t.
Moreover,a suPporting member 33 of considerablY large volume is assembled with both the side walls 32a and 32b at the oPened left side end bY means of a hinge shaft 40 which Passins through the two side walls 32a,32b and the suPpor ting member 33 interPosed between the two side frames.
Consequently,suPportins means of the inventors'afore-said Prior invention,consisting of the squared U shaPed frame,the hinge shaft 40 and t~le suPPortins member 33,cons-titute a rigid construction as a kind of Panelled wall and yet being large both in volume and weight.
Fig.3C is a schematic Plan view showing general shaPe and construction of the suPportins means as mentioned above.
SUMMARY OF THE INVENTIGN
In view of the a~ove-mentioned drawbacks encountered in the devices of Prior art as well as in the inventors~ Prior invention,the Present invention aims to Provide a thermal head suPprting means for a thermal Printins sYstem which satisfy the requirement of small volume,light weight,readilY
A
131675;i ~abrlcabie constructlon an~ uniforln dePression force between the ther~al he2d and the Pla~en roller with no Particular adjustment.
lt ls therefore the PrimarY object of this invention to Provide an imProved thermal head suPPorting means which can be fabricated as a small sized and lisht weisht member bY a simPle Process sucll as Punchins of thin metal Plate.
Another obiect of the Present invention is to Provide a thermal head suPportins means which can exert uniform force of dePression between the thermal head and the Platen roller of a thermal Printins sYstem.
Yet another object of the Present invention is to Pro-vide a thermal head suPporting means in which the dePression force between the thermal head and the Platen roller is aPplied on the central Part of a suPportins shaft in a range as small as Possible to obviate anY wavy movement of the thermal head and to allows the thermal head to seParate from the Platen roller when the Printins sYstem is not under its printing oPeration.
In order to achieve the above-mentioned objects.each of the Parts or comPonents constitutes the thermal head suPpor ting means according to the Present invention is designed to be small in si.ze.thin thickness and having such a shaPe as can be readily fabricated bY Press formins of metal sheet or by moulding Plastic material,in addition.the ~osition of the rotary shaft at which the thermal head suPportins means is attached to the shaft is Placed to the central Part of the rotary shaft with the intention to adoPt one point central suPport tYPe susPension. 1 31 675i~
DePression of a thermal head against a Platen roller is Performed bY urgins bY cam action a thermal head urging lever,having a length considerablY shorter in axial direc-tion,thereby the dePression can be aPplied via a dePressi~n sPrins disPosed at the central Part of and normal to the aforesaid rotarY shaft.
In addition,the thermal head is constructed to be moved away from the rotary shaft of the Platen roller when the thermal Printins sYstem is out of Printing oPeration~
By virtue of adoPting above mentioned construction,the thermal head suPporting means according to the Present invention has such feature that it can be made as a very light weight member together with its one Point central suPPortins tYpe construction and therebY can assure uniform dePression force against the Platen roller,and thus it can be used as a suPportins means esPecially suitable for an oPen frame tYpe thermal Printins sYstem wherein its uPper ~rame can be swung uPward or swung down to take its set PoS-Position to its mating lower frame.
The suPporting Plate for suPporting a thermal head is held at a Predetermined Position at the central Part of a suPportins shaft and is normallY urged bY a sPring to let the thermal head to effect swing motion,so there is no fear that any wavy motion of the thermal head would take Place~
Moreover the suPportinQ Plate is formed with a Pair of oblons throush holes each being normal to the suPportins shaft and direc~ed to a cam shaft for urging the thermal 1 3 1 67J-j head so as to allow fine adiustment of the thermal head in a direction normal to the Platen shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig.1 is a schematic side view showing relative Posi tion of a seneral Prior tY~e thermal head holder and a Pla-ten roller. Fis.2 is a schematic side view showing relative Position of an imProved thermal ~ead holder,Platen roller, ink ribbon and a Printins Paper as a Prior invention ProP
sed bY the inYentors of the Present invention.
Fi~.3A and 3B~respectivelY~is a Plan view and side view of the thermal head holder of the Prior invention as shown in Fis.2. Fig.3C is a schematic Plan view showing the relative shaPe and size of the thermal head holder shown in Fig.3A. Fig.4 is a schematic side view of an oPen-frame tYpe thermal Printins system Provided with a thermal head suPportins means. Fig.5A is a schematic Plan view showing a thermal head suPPortins means of the Present invention.
Fig.5B is a side view of a thermal head suPportins unit. Fig.5C is a side view of a Pair of micro switches and a Pair of micro switch cams.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
ExPlanation will now be made of a preferred embodiment of the Present invention bY referring to the accomPanying draw-ings.
Fig.4 is a schematic side view showing an oPen-frame tyPe thermal Printing sYstem equiPPed with a thermal head suPPorting means according to the Present invention.
Numeral 10 in the drawing shows an entire Part of the A
1 31 67~, thermal head suPporting means al~ost the whole Portion of which shown bY dotted lines, in which 21 is a Platen roller.
14 is a head guide Post~which slidahlY receives a thermal head 50 through a Pair of ball bearinss 15,re~ative to a Pair of oblong holes 14' formed almost vertically on each of a Pair of uPPer side frames 18 and 19.
The Pair of oblong holes 14' are formed to have a leng-th corresPondins to the swins stroke of the head suide Post 14 actuated bY a head dePressins cam,which will be exPlained later. Numerals 25 and 26, resPectively, are lower side frame at the right or the left side of the Printins sYstem~and numerals 27 and 27',resPeCtiVelY, are uPWardlY oPened recesseS
for adaPtins a ball bearing which iournallY receives each of the suide Post 14 when the uPper side frames 18 and 19 are swung down to be couPled with the inside of the lower side frames 25 and 26.
Adiustment is made under this couPled state,so that relative location of the heating element normal to the Platen shaft and its Parallelism can be assured.
Fig.5A is a Plan view of the thermal head suPportins means 10. In the drawing,numeral 9 is a head suPporting shaft which acts as a swing shaft through a thermal head urging lever exPlained later,so as to urge the thermal head 50 against the Platen roller 21 or to make it leave awaY
from the Platen roller 21 bY the aid of a thermal head retracting Plate 11,and the swing shaft 9 is Passed through both ri~ht and left UPper side frames 18 and 19 and is fur-ther fixed.at each axial ends,to each uPper side frame bY a 1 3 1 6 7,;
set screw.
Numeral 8 in the drawinss is a thermal head suPPortins plate having L-shape in cross section and fabricated of a metal Plate and havins twn flat Port:ions each beins bent Perpendicular to the other,and one oF the flat Portion 8'is secured alons the rear face of the thermal head 50 bY a set screw or screws,while the other flat Portion 8" is formed with an oblons throush hole 8"'.throush which the head suPP-orting shaft g can Pass and being Parallel to the side ~ace of the thermal head 50.
By virtue of this construction,the thermal head suPpor ting shaft 9 in assemblY is Passed through the oblong hole 8"' and the flat Portion ~"is resilientlY Positioned being urged bY a sPring 24 a~a~t a fixed stoPPer ring 24' atta-ched on the suPportins shaft 9~therebY the flat Portion ~"of the thermal head suPportins Plate Plays a role as an arm for swingably holding the thermal head 50.
The fixed stoPper ring 24' is comPosed of a Pair of rings,and if one ring(left side one in the drawing)is loca-ted at the center of the suPporting shaft 9,the thermal head suPportins Plate 8 could be held at the central Position of the thermal head suPportins shaft 9,and thus anY side Play>
namely,any wavy motion of the thermal head along the head suPPortins shaft leading to sliPPins off of the Printed dots can be Prevented from occuring.
Numeral 10' (as illustrated in Fig. 5B) denotes a thermal head urging lever as a formed member of thin thickness that can be fabricated either by punching and bending a metal plate or by molding 1 o 1 31 67~ j Plastic rllaterial.which le~/er has a configuration like an inverted thick and short ~ T ~ seen in Plan vi.ew and beins comPosed of three Parts 10~A,10~B and 10~C as exPlained later.
10'A is a toP Plate having almost a rectangular contour and the interior Part of which is Punched out to reduce its weight,and 10'B i.s a front Portion formed bY being bent lowered at the front end of the toP Plate and is bent again to Project forward,and 10'C is a side PeriPheral Portion bent downward to dePend from the side Periphery of the toP
Plate 10~A with its rear Portion slantlY descending rearward to constitute a connecting arm 10'D.
Numeral 11 is a thermal head retracting Plate tightlY
secured,~y a set screw or bY sPot welding,to the toP Plate 10'A at the Portion adjacent to its forward end and is rai-sed further bY bending uPward at right angle bY a Predeter-mined height at the Portion slightlY before the forward end of the toP Plate~and further bent at right angle to extend forward. This thermal head retracting Plate is far smaller in size and much lighter in weight as comPared with the above-mentioned thermal head ursing lever 10'.
Parallel distance between the forward end Portion of the thermal head urging lever 10'B and the thermal head retractins Plate 11 is set uP corresPonding to the diameter of the head urQing cam 12 to be slidablY disPosed between these two members.thereoY the difference between the maximum radius Portion and the minimum radius Portion of the head ursing cam determines the swing stroke of the thermal head 50.
Numeral 13 is a thermal head urging cam shaft extending between the uPPer side frames 1~ and 19 at both sides of the device and is driven bY a motor 19 through a set of gear 17 to rotate the head ursins cam 12.
Numeral ~ in Figs.5A and 5B denotes a sPrins guide Post inserted throush the hole oPened at the transverselY central Part near the frontmost end of the toP Plate 10'A of the thermal head urgins lever 10',which suide Post consists of a head formed with a slot for receiving the tiP end of a screw driver for turning,a neck extendins to the toP face of the thermal head 50 and a threaded Portion under the neck threaded with male thread(s)which threadablY engages the female thread formed on the thermal head,and therebY the extent of Proiection of the sPrins guide Post beYond the toP
Plate 10'A can be adjusted.
7 is a thermal head urging sPrins disPosed around the above-mentioned sPring guide Post 6 and in a gaP between the toP face of the thermal head 50 and the reverse face of the thermal head urging lever 10',and thus it acts to resili-entlY transmit an ursins force imParted bY the thermal head urging lever 10'to the thermal head 50,in addition sPring force of the urging sPring 7 can be adiusted bY adiusting the amount of the Proiection of the unthreaded shank of the spring guide Post 6.
28 and 28'are a Pair of micro swi.tches,while 29 and 29' are also a Pair of switch cams and the micro switch 28 and switch cam 29 make uP a co-working Parts~similarly the l 2 1 31 67 ,i, micro switch 2a'and switch Cam 29'make uP another co-working Parts .
ExPlanation will be made hereunder on the oPeration in seneral.function of dePression and suPPortins effected bY
the dePressins means of the Present invention.
When it becomes necessarY to dePress the thermal head 50 against the Platen roller 21 due to an aPplied signal instructing the start of Printins Y~Yellow)colour,the ther-mal head urging cam 12 is rotated bY a motor 16 to dePress the thermal head ursins lever 10',therebY the thermal head is dePressed against the outer surface of the Platen roller 21,then the microswitch 28 is turned ON bY the switch cam 29 and stoPs the rotation of the thermal head urging cam 12.
Under this Position>since the maximum radius Portion of the head urging cam 12 engages the frontmost end Portion 10'B of the thermal head urging lever lO',t~ results in dePression of the thermal head 50 against the Platen roller.
When it becomes necessarY>after having finished the Printins Y(Yellow)>to retract the thermal head 50 awaY from the Platen roller 21 immediatelY before rolling back the Paper sheet ready for subsequent M(magenta) Printins>the thermal head retracting Plate 11 is raised uPward bY rota-ting the motor to retract the thermal head,then the thermal head urging cam 12 is stoPped bY the micro switch 2~'.
Rotation of the thermal head ursing cam 12 accomPanies rotation of the switch cam 29 and allows subsequent rotation of the thermal head urging cam for next Printing.
As alreadY exPlained>the thermal head 50 is secured,at e, -1 3 1 67J ) the central Part of its rear end face,to one flat face of the thermal head suPPorting Plate 8,while the other flat face of the head suPPortins Plate 8 is resiliently and swin-gablY suPPorted with resPect to the head sUPporting Post 9 which Passes through the oblong hole 8"' formed through the flat face of the head suPportins Plate 8,as a consequence the thermal head 50 is suPported in a so-called one-Pcint central suPPort tYPe manner.
In addition,bY virtue of the oblong hole 8"',the ther-mal head suPporting Plate 8 is allowed for effecting fine adjustment with resPect to the suPportins shaft 9 in a dire-ction normal to the axis of the suPportins shaft.
In a state,where the thermal head 50 and sub-assembly of the thermal head urging lever 10' and the thermal head re-tracting Plate 11(referred to"head urging lever assembly")is couPled together,then the head suPportins shaft 9 is Passed through and the head urging cam is Positioned between the head urging lever 10' and the head retracting Plate 11,thus the thermal head 50 and the head urging lever assemblY as a whole functions as a thermal head dePressing unit.
Since all of the thermal head suPportins Plate~the head urging lever and the head retracting Plate constituting a thermal head urging unit are fabricated bY Press working of considerably thin metal sheets or Plates~and Yet the trans-verse width of the thermal head urging lever is less than one half the sPacing between two side ~rames and the central Portion of the ur~ing lever is Punched out,the thermal head urging unit is remarka~ly smaller in size and light in A
t 3 ~ 6 7 J ~
weight as comPared with thermal head holders of Prior art.
In addition,since the thermal head urging unit of this tYpe is tightlY couPled to the head suPportins shaft at 9 at its axial center bY the head suPPorting Plate under a sPring force and in a one-Point central suPport tYpe manner,there is no fear that the Point of suPporting should shift to cause wavY motion.
Fine adiustment bo~h forward and backward normal to the suPportins axis is Permitted bY the oblong hole formed thro-ugh the suPportins Plate 8.
Furthermore,holes formed in the side frames at right and left side through which the head suPport shaft and the head ursins cam shaft are Passed~can be formed bY means of precise Pressing technique,so the Positionins of these holes can be secured correctlY~so the Perpendicularity of both the suPportins shaft 9 and the head urging cam shaft 13 with resPect to both side frames,namely,the Parallelism of these two shafts also can be assured.
Since the thermal head suPportins means of the Present invention is Positioned and adjusted such that the relative Position of the heating element of the thermal head and the platen roller in the direction normal to the axis of the platen,and the Parallelism of these two members can be assu-red,in a state where the two uPper side frames 18 and 19 are swung down and couPled to the lower side frame 25 and 26,the force of dePression aPplied to the thermal head as shown in the above-mentioned embodiment is restrieted in an axial width of ~he toP face 10~A of the thermal head urging lever ,~
.
13167~, 10',which 's reallY a short range less ihan one half of the length of sPan between the two uPPer side frames 18 and 19,therefore it does not restrain the overall length of the thermal head.
As the thermal hea~ 50 is received,at its ooth axial en~s,by the head guide Post 14 and via a Pair of ball bear-rinss 15 in the oblong holes 14~.resPectively,sufficient freedom is given for machining,assembling and adiustment.
When the maximum radius Portion of the head ursins cam engages the front end Portion of the urging lever 10'B, dePression force is smoothly aPPlied to the Plat-en roller bY
the thermal head urging lever through the urging sPrins~
If the thermal head urging cam further rotates,the head retracting Plate is gradualy raised and the thermal head urging unit is moved to leave awaY from the Platen roller,on the other hand.when the maximum radius Portion of the thermal head ursing cam engages the head retracting Plate 11,the distance of the retracted thermal head from the Pla ten roller becomes maximum.
A thermal Printins sYstem~senerally~functions to Print alphanumeric and or image information on a Paper sheet bY
melting thermalY fusible ink aPplied on the surface of a thermal Printing ribbon or ribbons~by means of Passing both a Paper sheet and thermal Printins ribbon being overlaPped~
through a gaP between a thermal head and a Platen roller,and it has various features such as small size,light weight Yet allowing multi-colour Printins in a quite a simPle way.
In order to make the densitY of the Printed letters or images more uniform and to imProve the cleanliness bY using a thermal Printins sYstem of this kind,it is very imPortant 13167,i') to satisfY following two requirements,that is,to make a deP-resslon force between a thermal head and a matins Platen roller in the direction transverse to the width of Paper sheet more uniform,and at the same time to PerfectlY align the axis line of the Platen with the location of each of the heatins elements in the thermal head.
Because of this.it has been re~uired for most thermal Printing sYstem to adiust their dePression force in the transverse direction as uniform as Possible bY means of an adiusting screw or screws.while to alisn the axis line of the Platen roller with each heatins element relYins on the dimensional accuracY of the related Parts or comPonent Fig.1 is a side view showing the structural feature of the thermal head suPportins means of a conventional general tYpe thermal Printins system.
In the drawing,a thermal head 50 held bY a head holder 31 is dePressed on a Platen 21,and a thermal Printins Paper and a Printins ribbon being overlaPped with each other are Passed through the gaP between these two members and further fed uPward bY the Platen roller 21.
The head holder 31 is disPosed around a head holder shaft 31a rotatablY received bY the same frame carrYing said Platen roller 21 and is Pulled rightward bY a dePression sPrins 7 so that the thermal head 50 can be dePressed uPon the Platen roller 21.
The extent of the dePression force mentioned above can be adjusted bY an adjustment screw 37 disPosed on both sides of the head holder 31 so as to be uniform in the direction 1 31 675;
transverse to the direction of the PaPer sheet 5.
In the drawing,numeral 38 denotes a sensor for detec-ting the Position of a Printing ribbon 4,numeral 39 denotes a sensor holder,similarly,numeral 37'is a locking screw for fixins the adjustment screw 37 and 41 denotes a heat sink for radiating hea~ given from the thermal head 50.
However,there found following defects in the aforesaid conventional thermal head suPportins means,that is:
1~ Adiustment is required to maintain the dePression force uniform between the thermal head and Platen roller.
2) The construction of the suPportins means inevitably becomes comPlicated due to such adjustment means.
In order to obviate such drawbacks as exPlained above, the inventors of the Present invention Proposed a Prior invention directed to a suPportins means for a thermal head which enables the maintaining of a uniform depression force between a thermal head and a Platen roller,and filed a Patent aPplica tiontJapanese Patent APplication No.Sho 60(1985~-156~6, Pu~lished as JaPanese Patent Laid-OPen(Un-examined) Publi-cation No.Sho 62(1987)-611670].
Fig.2 is a schematic side view showing the main Portion of the above-mentioned thermal head suPporting means,wherein a rolled Paper sheet 5 payed out from a roller Rl is fed via a roller R2 onto the outer PeriPhery of a Platen roller ~1 and then fed leftward by turning back along the outer Peri-phery of the Platen roller 21.
On the other hand,an ink ribbon 4 aPplied with therma-lly fusible Printing ink is also payed out from a roller R3 131675 `
and overlaPped with the Paper sheet 5 on the outer Periphery o~ the Pl~ten roller 21 and then taken uP bY a take-uP
roller 39.
The thermal head suPPortins means as exPlained above and shown in Fig.3A and 3B is comPosed o~ following three main comPonents~:
1).a hinge shaft 40 disPosed bY ~ransverselY Passins through both outer side frames 30a and 30b and Placed in ParaIlel with the Platen roller 21, 2).a head holder 31 fitted around the outer Periphery of the Platen roller 21 through a rolling bearing 35 and is PoSitioned halfway between the hinge shaft 40 and the PIaten roller 21 and holds a thermal head 50 at the side confron-ting with the Platen roller 21,and 3).a Pair of coil sPrinss 7a and 7b attached at both axial ends of the head holder 31 so as to resilientlY urge the head holder 31 against the shaft of the Platen wheel 21.
Having a construction as explained above, the head holder 31 can be swung in a see-saw like motion around the hinge shaft 40 via the rolling hearings 35.
In addition,the dePression force exerted between the Platen roller 21 and the thermal head can be made uniform over the entire width of the printing PaPer~and bY virtue of this Prior tYpe thermal head suPportins means,an entirelY
uniform dePression force can be assured between the thermal head and the Platen roller with no Particular adjustment.
It is to be noted,however,that the head holder 31 of the prior invention consists of, 1 31 675., 1) a frame mem~er 32 ~lavirlg its transverse wldth almost the same as that of the outer frames 30a and 30b and its confisuration like a squared U shape seen in plan view, and 2) a suPPorting member ~3 carrYing a ball bearins 35 on the oPened face side.
Both side walls 32a.32b and a transverse connecting bar 32c of the frame member 32 are jntegrally formed bY such means as aluminum alloY die castins technique or the like, and these members themselves have a considerable volume tosether with a heavy weig~t.
Moreover,a suPporting member 33 of considerablY large volume is assembled with both the side walls 32a and 32b at the oPened left side end bY means of a hinge shaft 40 which Passins through the two side walls 32a,32b and the suPpor ting member 33 interPosed between the two side frames.
Consequently,suPportins means of the inventors'afore-said Prior invention,consisting of the squared U shaPed frame,the hinge shaft 40 and t~le suPPortins member 33,cons-titute a rigid construction as a kind of Panelled wall and yet being large both in volume and weight.
Fig.3C is a schematic Plan view showing general shaPe and construction of the suPportins means as mentioned above.
SUMMARY OF THE INVENTIGN
In view of the a~ove-mentioned drawbacks encountered in the devices of Prior art as well as in the inventors~ Prior invention,the Present invention aims to Provide a thermal head suPprting means for a thermal Printins sYstem which satisfy the requirement of small volume,light weight,readilY
A
131675;i ~abrlcabie constructlon an~ uniforln dePression force between the ther~al he2d and the Pla~en roller with no Particular adjustment.
lt ls therefore the PrimarY object of this invention to Provide an imProved thermal head suPPorting means which can be fabricated as a small sized and lisht weisht member bY a simPle Process sucll as Punchins of thin metal Plate.
Another obiect of the Present invention is to Provide a thermal head suPportins means which can exert uniform force of dePression between the thermal head and the Platen roller of a thermal Printins sYstem.
Yet another object of the Present invention is to Pro-vide a thermal head suPporting means in which the dePression force between the thermal head and the Platen roller is aPplied on the central Part of a suPportins shaft in a range as small as Possible to obviate anY wavy movement of the thermal head and to allows the thermal head to seParate from the Platen roller when the Printins sYstem is not under its printing oPeration.
In order to achieve the above-mentioned objects.each of the Parts or comPonents constitutes the thermal head suPpor ting means according to the Present invention is designed to be small in si.ze.thin thickness and having such a shaPe as can be readily fabricated bY Press formins of metal sheet or by moulding Plastic material,in addition.the ~osition of the rotary shaft at which the thermal head suPportins means is attached to the shaft is Placed to the central Part of the rotary shaft with the intention to adoPt one point central suPport tYPe susPension. 1 31 675i~
DePression of a thermal head against a Platen roller is Performed bY urgins bY cam action a thermal head urging lever,having a length considerablY shorter in axial direc-tion,thereby the dePression can be aPplied via a dePressi~n sPrins disPosed at the central Part of and normal to the aforesaid rotarY shaft.
In addition,the thermal head is constructed to be moved away from the rotary shaft of the Platen roller when the thermal Printins sYstem is out of Printing oPeration~
By virtue of adoPting above mentioned construction,the thermal head suPporting means according to the Present invention has such feature that it can be made as a very light weight member together with its one Point central suPPortins tYpe construction and therebY can assure uniform dePression force against the Platen roller,and thus it can be used as a suPportins means esPecially suitable for an oPen frame tYpe thermal Printins sYstem wherein its uPper ~rame can be swung uPward or swung down to take its set PoS-Position to its mating lower frame.
The suPporting Plate for suPporting a thermal head is held at a Predetermined Position at the central Part of a suPportins shaft and is normallY urged bY a sPring to let the thermal head to effect swing motion,so there is no fear that any wavy motion of the thermal head would take Place~
Moreover the suPportinQ Plate is formed with a Pair of oblons throush holes each being normal to the suPportins shaft and direc~ed to a cam shaft for urging the thermal 1 3 1 67J-j head so as to allow fine adiustment of the thermal head in a direction normal to the Platen shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig.1 is a schematic side view showing relative Posi tion of a seneral Prior tY~e thermal head holder and a Pla-ten roller. Fis.2 is a schematic side view showing relative Position of an imProved thermal ~ead holder,Platen roller, ink ribbon and a Printins Paper as a Prior invention ProP
sed bY the inYentors of the Present invention.
Fi~.3A and 3B~respectivelY~is a Plan view and side view of the thermal head holder of the Prior invention as shown in Fis.2. Fig.3C is a schematic Plan view showing the relative shaPe and size of the thermal head holder shown in Fig.3A. Fig.4 is a schematic side view of an oPen-frame tYpe thermal Printins system Provided with a thermal head suPportins means. Fig.5A is a schematic Plan view showing a thermal head suPPortins means of the Present invention.
Fig.5B is a side view of a thermal head suPportins unit. Fig.5C is a side view of a Pair of micro switches and a Pair of micro switch cams.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
ExPlanation will now be made of a preferred embodiment of the Present invention bY referring to the accomPanying draw-ings.
Fig.4 is a schematic side view showing an oPen-frame tyPe thermal Printing sYstem equiPPed with a thermal head suPPorting means according to the Present invention.
Numeral 10 in the drawing shows an entire Part of the A
1 31 67~, thermal head suPporting means al~ost the whole Portion of which shown bY dotted lines, in which 21 is a Platen roller.
14 is a head guide Post~which slidahlY receives a thermal head 50 through a Pair of ball bearinss 15,re~ative to a Pair of oblong holes 14' formed almost vertically on each of a Pair of uPPer side frames 18 and 19.
The Pair of oblong holes 14' are formed to have a leng-th corresPondins to the swins stroke of the head suide Post 14 actuated bY a head dePressins cam,which will be exPlained later. Numerals 25 and 26, resPectively, are lower side frame at the right or the left side of the Printins sYstem~and numerals 27 and 27',resPeCtiVelY, are uPWardlY oPened recesseS
for adaPtins a ball bearing which iournallY receives each of the suide Post 14 when the uPper side frames 18 and 19 are swung down to be couPled with the inside of the lower side frames 25 and 26.
Adiustment is made under this couPled state,so that relative location of the heating element normal to the Platen shaft and its Parallelism can be assured.
Fig.5A is a Plan view of the thermal head suPportins means 10. In the drawing,numeral 9 is a head suPporting shaft which acts as a swing shaft through a thermal head urging lever exPlained later,so as to urge the thermal head 50 against the Platen roller 21 or to make it leave awaY
from the Platen roller 21 bY the aid of a thermal head retracting Plate 11,and the swing shaft 9 is Passed through both ri~ht and left UPper side frames 18 and 19 and is fur-ther fixed.at each axial ends,to each uPper side frame bY a 1 3 1 6 7,;
set screw.
Numeral 8 in the drawinss is a thermal head suPPortins plate having L-shape in cross section and fabricated of a metal Plate and havins twn flat Port:ions each beins bent Perpendicular to the other,and one oF the flat Portion 8'is secured alons the rear face of the thermal head 50 bY a set screw or screws,while the other flat Portion 8" is formed with an oblons throush hole 8"'.throush which the head suPP-orting shaft g can Pass and being Parallel to the side ~ace of the thermal head 50.
By virtue of this construction,the thermal head suPpor ting shaft 9 in assemblY is Passed through the oblong hole 8"' and the flat Portion ~"is resilientlY Positioned being urged bY a sPring 24 a~a~t a fixed stoPPer ring 24' atta-ched on the suPportins shaft 9~therebY the flat Portion ~"of the thermal head suPportins Plate Plays a role as an arm for swingably holding the thermal head 50.
The fixed stoPper ring 24' is comPosed of a Pair of rings,and if one ring(left side one in the drawing)is loca-ted at the center of the suPporting shaft 9,the thermal head suPportins Plate 8 could be held at the central Position of the thermal head suPportins shaft 9,and thus anY side Play>
namely,any wavy motion of the thermal head along the head suPPortins shaft leading to sliPPins off of the Printed dots can be Prevented from occuring.
Numeral 10' (as illustrated in Fig. 5B) denotes a thermal head urging lever as a formed member of thin thickness that can be fabricated either by punching and bending a metal plate or by molding 1 o 1 31 67~ j Plastic rllaterial.which le~/er has a configuration like an inverted thick and short ~ T ~ seen in Plan vi.ew and beins comPosed of three Parts 10~A,10~B and 10~C as exPlained later.
10'A is a toP Plate having almost a rectangular contour and the interior Part of which is Punched out to reduce its weight,and 10'B i.s a front Portion formed bY being bent lowered at the front end of the toP Plate and is bent again to Project forward,and 10'C is a side PeriPheral Portion bent downward to dePend from the side Periphery of the toP
Plate 10~A with its rear Portion slantlY descending rearward to constitute a connecting arm 10'D.
Numeral 11 is a thermal head retracting Plate tightlY
secured,~y a set screw or bY sPot welding,to the toP Plate 10'A at the Portion adjacent to its forward end and is rai-sed further bY bending uPward at right angle bY a Predeter-mined height at the Portion slightlY before the forward end of the toP Plate~and further bent at right angle to extend forward. This thermal head retracting Plate is far smaller in size and much lighter in weight as comPared with the above-mentioned thermal head ursing lever 10'.
Parallel distance between the forward end Portion of the thermal head urging lever 10'B and the thermal head retractins Plate 11 is set uP corresPonding to the diameter of the head urQing cam 12 to be slidablY disPosed between these two members.thereoY the difference between the maximum radius Portion and the minimum radius Portion of the head ursing cam determines the swing stroke of the thermal head 50.
Numeral 13 is a thermal head urging cam shaft extending between the uPPer side frames 1~ and 19 at both sides of the device and is driven bY a motor 19 through a set of gear 17 to rotate the head ursins cam 12.
Numeral ~ in Figs.5A and 5B denotes a sPrins guide Post inserted throush the hole oPened at the transverselY central Part near the frontmost end of the toP Plate 10'A of the thermal head urgins lever 10',which suide Post consists of a head formed with a slot for receiving the tiP end of a screw driver for turning,a neck extendins to the toP face of the thermal head 50 and a threaded Portion under the neck threaded with male thread(s)which threadablY engages the female thread formed on the thermal head,and therebY the extent of Proiection of the sPrins guide Post beYond the toP
Plate 10'A can be adjusted.
7 is a thermal head urging sPrins disPosed around the above-mentioned sPring guide Post 6 and in a gaP between the toP face of the thermal head 50 and the reverse face of the thermal head urging lever 10',and thus it acts to resili-entlY transmit an ursins force imParted bY the thermal head urging lever 10'to the thermal head 50,in addition sPring force of the urging sPring 7 can be adiusted bY adiusting the amount of the Proiection of the unthreaded shank of the spring guide Post 6.
28 and 28'are a Pair of micro swi.tches,while 29 and 29' are also a Pair of switch cams and the micro switch 28 and switch cam 29 make uP a co-working Parts~similarly the l 2 1 31 67 ,i, micro switch 2a'and switch Cam 29'make uP another co-working Parts .
ExPlanation will be made hereunder on the oPeration in seneral.function of dePression and suPPortins effected bY
the dePressins means of the Present invention.
When it becomes necessarY to dePress the thermal head 50 against the Platen roller 21 due to an aPplied signal instructing the start of Printins Y~Yellow)colour,the ther-mal head urging cam 12 is rotated bY a motor 16 to dePress the thermal head ursins lever 10',therebY the thermal head is dePressed against the outer surface of the Platen roller 21,then the microswitch 28 is turned ON bY the switch cam 29 and stoPs the rotation of the thermal head urging cam 12.
Under this Position>since the maximum radius Portion of the head urging cam 12 engages the frontmost end Portion 10'B of the thermal head urging lever lO',t~ results in dePression of the thermal head 50 against the Platen roller.
When it becomes necessarY>after having finished the Printins Y(Yellow)>to retract the thermal head 50 awaY from the Platen roller 21 immediatelY before rolling back the Paper sheet ready for subsequent M(magenta) Printins>the thermal head retracting Plate 11 is raised uPward bY rota-ting the motor to retract the thermal head,then the thermal head urging cam 12 is stoPped bY the micro switch 2~'.
Rotation of the thermal head ursing cam 12 accomPanies rotation of the switch cam 29 and allows subsequent rotation of the thermal head urging cam for next Printing.
As alreadY exPlained>the thermal head 50 is secured,at e, -1 3 1 67J ) the central Part of its rear end face,to one flat face of the thermal head suPPorting Plate 8,while the other flat face of the head suPPortins Plate 8 is resiliently and swin-gablY suPPorted with resPect to the head sUPporting Post 9 which Passes through the oblong hole 8"' formed through the flat face of the head suPportins Plate 8,as a consequence the thermal head 50 is suPported in a so-called one-Pcint central suPPort tYPe manner.
In addition,bY virtue of the oblong hole 8"',the ther-mal head suPporting Plate 8 is allowed for effecting fine adjustment with resPect to the suPportins shaft 9 in a dire-ction normal to the axis of the suPportins shaft.
In a state,where the thermal head 50 and sub-assembly of the thermal head urging lever 10' and the thermal head re-tracting Plate 11(referred to"head urging lever assembly")is couPled together,then the head suPportins shaft 9 is Passed through and the head urging cam is Positioned between the head urging lever 10' and the head retracting Plate 11,thus the thermal head 50 and the head urging lever assemblY as a whole functions as a thermal head dePressing unit.
Since all of the thermal head suPportins Plate~the head urging lever and the head retracting Plate constituting a thermal head urging unit are fabricated bY Press working of considerably thin metal sheets or Plates~and Yet the trans-verse width of the thermal head urging lever is less than one half the sPacing between two side ~rames and the central Portion of the ur~ing lever is Punched out,the thermal head urging unit is remarka~ly smaller in size and light in A
t 3 ~ 6 7 J ~
weight as comPared with thermal head holders of Prior art.
In addition,since the thermal head urging unit of this tYpe is tightlY couPled to the head suPportins shaft at 9 at its axial center bY the head suPPorting Plate under a sPring force and in a one-Point central suPport tYpe manner,there is no fear that the Point of suPporting should shift to cause wavY motion.
Fine adiustment bo~h forward and backward normal to the suPportins axis is Permitted bY the oblong hole formed thro-ugh the suPportins Plate 8.
Furthermore,holes formed in the side frames at right and left side through which the head suPport shaft and the head ursins cam shaft are Passed~can be formed bY means of precise Pressing technique,so the Positionins of these holes can be secured correctlY~so the Perpendicularity of both the suPportins shaft 9 and the head urging cam shaft 13 with resPect to both side frames,namely,the Parallelism of these two shafts also can be assured.
Since the thermal head suPportins means of the Present invention is Positioned and adjusted such that the relative Position of the heating element of the thermal head and the platen roller in the direction normal to the axis of the platen,and the Parallelism of these two members can be assu-red,in a state where the two uPper side frames 18 and 19 are swung down and couPled to the lower side frame 25 and 26,the force of dePression aPplied to the thermal head as shown in the above-mentioned embodiment is restrieted in an axial width of ~he toP face 10~A of the thermal head urging lever ,~
.
13167~, 10',which 's reallY a short range less ihan one half of the length of sPan between the two uPPer side frames 18 and 19,therefore it does not restrain the overall length of the thermal head.
As the thermal hea~ 50 is received,at its ooth axial en~s,by the head guide Post 14 and via a Pair of ball bear-rinss 15 in the oblong holes 14~.resPectively,sufficient freedom is given for machining,assembling and adiustment.
When the maximum radius Portion of the head ursins cam engages the front end Portion of the urging lever 10'B, dePression force is smoothly aPPlied to the Plat-en roller bY
the thermal head urging lever through the urging sPrins~
If the thermal head urging cam further rotates,the head retracting Plate is gradualy raised and the thermal head urging unit is moved to leave awaY from the Platen roller,on the other hand.when the maximum radius Portion of the thermal head ursing cam engages the head retracting Plate 11,the distance of the retracted thermal head from the Pla ten roller becomes maximum.
Claims (5)
1. A thermal head supporting means for a thermal printing system for positioning an ink ribbon and a paper sheet to be printed by clamping them between a platen roller and a thermal head being opposed with each other, which comprises:
a supporting shaft providing a swing axis and attached to both side frames of said thermal printing system by passing through said side frames and in parallel with said platen roller, a thermal head supporting plate disposed between said supporting shaft and said platen roller for attaching said thermal head to the axially central portion of said supporting shaft and swingably supporting said thermal head about said swing axis in a one-point central support manner so that said thermal head can be depressed against or retracted away from said platen roller, a thermal head urging lever assembly consisting of, a rear end portion swingably connected to said head supporting plate at two positions spaced apart from each other and interposing said head supporting plate between said two positions, an intermediate portion connected to said thermal head, a forward portion for transmitting a force to urge said thermal head against or separate from said platen roller, a cam shaft consisting of, a cam engaging said force transmitting portion of said thermal head urging lever assembly and a shaft to be journally received in a predetermined position of said frame, a driving motor for rotating said cam shaft and equipped with at least a switch means for starting or stopping said driving motor, and a guide post connecting both said central portion of said thermal head and said thermal head urging lever assembly, thereby a force urging said thermal head to depress against or retract away from said platen roller is applied through said guide post in a one-point central manner and the region applied with said urging force is limited within the transverse width of said thermal head urging lever assembly less than the span of said both side frames of said thermal printing system.
a supporting shaft providing a swing axis and attached to both side frames of said thermal printing system by passing through said side frames and in parallel with said platen roller, a thermal head supporting plate disposed between said supporting shaft and said platen roller for attaching said thermal head to the axially central portion of said supporting shaft and swingably supporting said thermal head about said swing axis in a one-point central support manner so that said thermal head can be depressed against or retracted away from said platen roller, a thermal head urging lever assembly consisting of, a rear end portion swingably connected to said head supporting plate at two positions spaced apart from each other and interposing said head supporting plate between said two positions, an intermediate portion connected to said thermal head, a forward portion for transmitting a force to urge said thermal head against or separate from said platen roller, a cam shaft consisting of, a cam engaging said force transmitting portion of said thermal head urging lever assembly and a shaft to be journally received in a predetermined position of said frame, a driving motor for rotating said cam shaft and equipped with at least a switch means for starting or stopping said driving motor, and a guide post connecting both said central portion of said thermal head and said thermal head urging lever assembly, thereby a force urging said thermal head to depress against or retract away from said platen roller is applied through said guide post in a one-point central manner and the region applied with said urging force is limited within the transverse width of said thermal head urging lever assembly less than the span of said both side frames of said thermal printing system.
2. A thermal head supporting means for a thermal printing system as claimed in claim 1, wherein said thermal head supporting plate is fabricated of a metal plate or plastic material and consisting of two flat portions normal to with each other, one of which is passed through by said thermal head supporting shaft and having an oblong hole being normal to said supporting shaft and being longer toward said cam shaft, thereby enabling fine adjustment of said thermal head in a direction normal to said platen roller.
3. A thermal head supporting means for a thermal printing system as claimed in claim 1, wherein said thermal head urging lever assembly is fabricated of metal plate or plastic material and said intermediate portion consists of a top plate fixed to the front end of said thermal head at one point and a pair of side portions, depending down from the both side margins, the rear portion of which top plate extends slantingly downward and being fitted around said thermal head supporting shaft as a pair of connecting arms which swingably support said thermal head urging lever at both axial outside portions of said head supporting plate.
4. A thermal head supporting means for a thermal printing system as claimed in claim 1, wherein said thermal head urging lever assembly is fabricated of metal plate or plastics and said force transmitting portion consists of a narrow width front portion bent at the front end of said top plate so as to extend parallel with the top face of said thermal head, and a retracting plate tightly fixed to the front end of said top plate bent upright and then bent again to extend parallel with said front portion at predetermined distance.
5. A thermal head supporting means for a thermal printing system as claimed in any one of claims 1 through 4 directed to such supporting means for a thermal head attached on the upper frame of an open-frame type thermal printing system and functions to support said thermal head in parallel with said platen roller disposed on the lower frame, wherein said upper frame can be swung down around a hinged shaft and coupled with said lower frame and set ready for printing operation, assuring that adjustments for both the parallelism and the relative position between said thermal head and the platen roller with respect to the direction normal to the platen roller has already been finished, in a state where a pair of head guide posts supporting said thermal head through a bearing has engaged with the recess each formed on each side frame of said lower frame.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63(1988)-239066 | 1988-09-26 | ||
| JP63239066A JP2560448B2 (en) | 1988-09-26 | 1988-09-26 | Thermal head holding structure for thermal transfer recording device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1316756C true CA1316756C (en) | 1993-04-27 |
Family
ID=17039352
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000612899A Expired - Fee Related CA1316756C (en) | 1988-09-26 | 1989-09-25 | Thermal head supporting means for a thermal printing system |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US4962392A (en) |
| EP (1) | EP0361826B1 (en) |
| JP (1) | JP2560448B2 (en) |
| CA (1) | CA1316756C (en) |
| DE (1) | DE68921827T2 (en) |
Families Citing this family (24)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5106213A (en) * | 1990-06-01 | 1992-04-21 | Smith Corona Corporation | Thermal print head control mechanism |
| US5238314A (en) * | 1990-07-13 | 1993-08-24 | Tokyo Electric Co., Ltd. | Transfer printer with ribbon lock |
| US5180236A (en) * | 1990-07-13 | 1993-01-19 | Tokyo Electric Co., Ltd. | Transfer printer |
| US5092688A (en) * | 1990-08-31 | 1992-03-03 | Cognitive Solutions, Inc. | Portable barcode printer |
| US5474394A (en) * | 1991-05-24 | 1995-12-12 | Mitsubishi Denki Kabushiki Kaisha | Printing apparatus |
| US5921687A (en) * | 1991-05-24 | 1999-07-13 | Mitsubishi Denki Kabushiki Kaisha | Printing apparatus |
| DE4224533A1 (en) * | 1991-07-25 | 1993-01-28 | Kanzaki Paper Mfg Co Ltd | Thermal printer with improved head mounting - has head unit mounted on frame locating in pivot mounted housing that is located by lever and which applies spring force to head |
| US5379056A (en) * | 1992-01-10 | 1995-01-03 | Markem Corporation | Multi-color thermal transfer printer with arcuate print head arrangement and printing pressure adjustment |
| US5176458A (en) * | 1992-06-08 | 1993-01-05 | Eastman Kodak Company | Multiple position thermal printer head mechanism which is disturbance insensitive |
| US5440328A (en) * | 1992-10-05 | 1995-08-08 | Atlantek, Inc. | Single-pass multi-color thermal printer |
| US5570961A (en) * | 1993-05-31 | 1996-11-05 | Victor Company Of Japan, Ltd. | Color printer feeding mechanism |
| US5541635A (en) * | 1994-03-18 | 1996-07-30 | Mettler-Toledo, Inc. | Printer mechanism |
| JP2855325B2 (en) * | 1996-05-09 | 1999-02-10 | アグファ・ゲヴェルト・ナームロゼ・ベンノートチャップ | Thermal printer with adjustable thermal head |
| DE19720671A1 (en) * | 1996-05-29 | 1997-12-04 | Eastman Kodak Co | Adjustable print head holder for printer, copier, or facsimile device |
| US6261009B1 (en) | 1996-11-27 | 2001-07-17 | Zih Corporation | Thermal printer |
| KR100320931B1 (en) * | 1998-09-17 | 2002-02-04 | 이형도 | A device for controlling pressure of head in thermal printer |
| GB2391514B (en) | 2002-08-06 | 2006-03-22 | Markem Tech Ltd | Printing apparatus and methods |
| JP4006701B2 (en) * | 2003-07-28 | 2007-11-14 | 船井電機株式会社 | Thermal transfer printer |
| US7355613B2 (en) * | 2005-08-03 | 2008-04-08 | Carestream Health, Inc. | Thermal recording system employing adjustable head pressure |
| JP4824368B2 (en) * | 2005-08-31 | 2011-11-30 | 株式会社サトー | Printing unit |
| JP2011062898A (en) * | 2009-09-16 | 2011-03-31 | Toshiba Tec Corp | Head mechanism and printer |
| US8985730B2 (en) | 2011-11-07 | 2015-03-24 | Zih Corp. | Media processing device with enhanced media and ribbon loading and unloading features |
| US9744784B1 (en) | 2016-02-05 | 2017-08-29 | Zih Corp. | Printhead carriers and adapters |
| CN106739583B (en) * | 2016-11-30 | 2019-03-15 | 郑州新世纪数码科技股份有限公司 | The safety guard at trolley frame both ends |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2403889A1 (en) * | 1977-09-21 | 1979-04-20 | Logabax | MODULAR MOBILE PRINT HEAD MOSAIC PRINTER, WITH A PRINTING BLOCK MECHANICALLY INDEPENDENT FROM THE PRINT MEDIA INPUT AND DRIVE BLOCKS |
| CH635657A5 (en) * | 1980-05-20 | 1983-04-15 | Hermes Precisa International | COUPLING MECHANISM. |
| JPS59148349U (en) * | 1983-03-25 | 1984-10-03 | 株式会社石田衡器製作所 | printer |
| JPS6085955A (en) * | 1983-10-18 | 1985-05-15 | Hitachi Cable Ltd | Printer for flat-type coated optical fiber |
| JPS60196369A (en) * | 1984-03-19 | 1985-10-04 | Fujitsu Ltd | Thermal printer |
| JPS61102270A (en) * | 1984-10-25 | 1986-05-20 | Mitsubishi Electric Corp | Thermal head supporting mechanism |
| JPS61115651A (en) * | 1984-11-09 | 1986-06-03 | Ishikawajima Harima Heavy Ind Co Ltd | Method and device for continuous casting of metal |
| US4835547A (en) * | 1986-11-10 | 1989-05-30 | Kanzaki Paper Manufacturing Co., Ltd. | Thermal printer with a mechanism for preventing a recording sheet's meandering |
| JPS64670A (en) * | 1987-06-23 | 1989-01-05 | Seiko Epson Corp | Socket component device |
| US4750880A (en) * | 1987-11-09 | 1988-06-14 | Eastman Kodak Company | Compliant print head loading mechanism for thermal printers |
-
1988
- 1988-09-26 JP JP63239066A patent/JP2560448B2/en not_active Expired - Fee Related
-
1989
- 1989-09-25 US US07/411,801 patent/US4962392A/en not_active Expired - Fee Related
- 1989-09-25 DE DE68921827T patent/DE68921827T2/en not_active Expired - Fee Related
- 1989-09-25 CA CA000612899A patent/CA1316756C/en not_active Expired - Fee Related
- 1989-09-25 EP EP89309722A patent/EP0361826B1/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| EP0361826A3 (en) | 1990-12-27 |
| DE68921827D1 (en) | 1995-04-27 |
| JPH0288278A (en) | 1990-03-28 |
| EP0361826B1 (en) | 1995-03-22 |
| DE68921827T2 (en) | 1995-11-02 |
| EP0361826A2 (en) | 1990-04-04 |
| JP2560448B2 (en) | 1996-12-04 |
| US4962392A (en) | 1990-10-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1316756C (en) | Thermal head supporting means for a thermal printing system | |
| US4647234A (en) | Thermal printer | |
| JP3326780B2 (en) | Printer | |
| DE60128163T2 (en) | inkjet | |
| EP0348176A2 (en) | Thermal printing system | |
| JP3215609B2 (en) | Ink jet recording device | |
| US6811336B2 (en) | Registration cam for a printing press | |
| JPH01122468A (en) | Method for setting cut paper to printer | |
| JPS6136371Y2 (en) | ||
| JP3440961B2 (en) | Printer paper feeder | |
| JP3278029B2 (en) | Printing device | |
| JPH0524305A (en) | Head pressing device of printer | |
| JPH0434041Y2 (en) | ||
| JPH0395038A (en) | Paper feeding tray | |
| JP2737267B2 (en) | Automatic paper thickness detection mechanism setting method | |
| JPH03140273A (en) | Paper feed mechanism in printer | |
| JPH09220841A (en) | Ink jet printer system | |
| JPH05124274A (en) | Printer | |
| JPS61139449A (en) | Dot matrix printer | |
| JPH04216084A (en) | Thermal printer | |
| JPH02276662A (en) | Gap adjuster of serial printer | |
| JPH0481519B2 (en) | ||
| JP2000335072A (en) | Printing pressure regulating mechanism for stencil printer | |
| JPS62128777A (en) | Mechanism for adjusting printing gap of printing apparatus | |
| JPS6253858A (en) | Paper feed mechanism of printer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |