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Publication numberUS2370309 A
Publication typeGrant
Publication dateFeb 27, 1945
Filing dateDec 26, 1942
Priority dateDec 26, 1942
Publication numberUS 2370309 A, US 2370309A, US-A-2370309, US2370309 A, US2370309A
InventorsHartwig Walter J
Original AssigneeD J Murray Mfg Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Circular unit heater
US 2370309 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Feb. 27, v W- L HARTWlG CIRCULAR UNIT HEATER F'iled- Dec. 26, 1942 3 Sheets-Sheet 1 /t'g Z7 HIIH'IIU 34 Z5 mi; g i Mmmm f www W mi llHlIlIWWHVlHHHi a f@ n @Mmmm Juumnnnnn f' Mw a.


Feb. 27, 1945.

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Feb 27, 1945- w. J. HARTWIG a CIRCULAR UNIT HEATER Filed Dec. 26, 1942 3 Sheets-Shee't 3 'Patented ret. 27, 1.945 7 CIRCULAR UNIT HEATER Walter J. Hartwig, Wausau, Wis., assignor to- D. J. Murray Manufacturing a corporation of Wisconsin Co., Wausau, Wis.,

Application December 26, 1942, Serial No. 470,157

" roxanne. 101.2574137) The present invention relates generally to improvements in the art of conditioning and distributing air or other gases, and relates more especially to various improvements in the construction and operation of circular heat transfer devices of the type having one or more heat transfercoils and an air circulating fan or blower embodied in a single unit which is adapted for installation directlywithin or closely adjoining the space in which the air is to b'e conditioned.,

The principal object of this invention is to -provide a new and useful unit heater or cooler which is simple and compact in construction,

' vortex lbreakers,'diilusers and airv distributors of different types, and having a moto-r driven air circulating fan the propelling mo-tor of which is amply ventilated and protected against excessive heat a-t all times.

To provide an improved unit heater assemblage which occupies minimum space, which is highly attractive in appearance, and which can and which is also highly efficient in operationv and extremely exible in its adaptations.

Sonie of the more important specific objects of the present invention are as follows:

To provide an improved air conditioner having one or more approximately circular .heat transfer coils each provided with a multiplicity of heat radiating fins, and which may be readily assembled for most effective cooperation with an air circulating fan; or blower.

YTo provide an improved heat transfer assem blage for heating or coo-ling a continuous stream of air or other gas, which is adapted to most effectively distributethe treated gas ,throughout the Zone of utilization thereof.

To provide an improved unit heater comprising annular heat transfer elements and an air Vcirculating fan ooperating therewith, which is well adapted for overhead suspension with its central axis'disposed either vertically, or horizontally, or in any intermediate angular position.

To provide a heating unit having one or more annular heat transfer coils provided with, inwardly directed hea't radiating ns formed to produce-enlarged air 'entrance area and to thereby minimize the entry losses.

To provide a most ,eflicient, compact and durable unit heater especially adapted forv downblow distribution of heated air, and having interchangeably similar heat transfer coils which ymay be readily assembled in different numbers so as to produce units of greater or lesser capacities.

To provide a heating assembly lcomprising relatively few simple'partsjvhich may be readily constructed and conveniently assembled, and in which the direction of flow of theair and of the heating medium through the unit maybe reversed withoutmaterially 'affecting the Operating eilicieiicy of the assembly.- l

To provide an improved heat transfer struc.-

ture adapted to interchangeably cooperate with be manufactured vand sold at moderate cost for diverse uses.

These and other specic objects and advantages will be apparent from the subsequent description.

A clear conception ofthe various features constituting the present improvement, and of the construction and operation of a unit heater embodying the invention, may be had `by referring` to the drawings accompanying and forming a part of this specification wherein like reference characters designate 'the same or similar parts in the various views.

Fig. 1 is a side elevation of a vertically disposed down-below unit heater built in accordance with .this invention;

Fig. 2 is a bottom view of the vertical unit heater of Fig. 1; v

Fig. 3 is a rather irregular vertical section llrough the down-below unit heater, taken along the lines 3-3 of Fig. 4;,

Fig. 4 is a transverse horizontal section through the unit heater taken along the line 4 4 of Fig. 3;

Fig. 5 is a side elvation of a 'horizontally disposed similar unit heater; and

Fig. 6 is a front view of the horizontally disposed unit heater.

While the invention has been shown and described herein Ias being especially applicable to circular unit heaters each embodying a series of annular finned heat transfer coils and a motor driven fan cooperating therewith, it is to be understood that it is" not my desire or intent to unnecessarily restrict the scope orthe utility ofA the improvement by virtue of this specific embodiment, since some of the improved features may also be advantageously applied to coolers for air o r other gases.

Referring to the drawings, the improved circular heat transfer unit comprises in general several concentric annular heating sections or coils 8 of interchangeably similar construction each having an internal continuous chamber. 9 forv Vheating medium, and a multiplicity of external radiating fins I Il, I I directed inwardly toward the center of the annulus; opposite side sheets l2, I3

' or pipe plugs, and some .f The radiating fins l0,

. the unit.

adjacent to thebosses 20,' vpermit'free circulation of the air about these I0, II are so formed and Adisposed that they able by' means of an electric motor i6 mounted or" .the side sheetwithin a central depression I1 i2 to produce @a continuous circulation of air through the passage I4; and a vortex breaker or diffuser IS detachably secured to the tubular outthe heating sections; a rotary let portion lil of the other side sheet I3, coaxially i of the fan i5 and motor I5.

The improved annular heat transfer sections or coils 8 with the iins Ill, iI formed integral therewith, may be readily constructed by ordinary foundry methods, and each of these coils 8 is provided with a series of integral bosses 25, 2i which are tapped for the reception of piping, nipples, oi which are adapted to coact with the corresponding bosses of adjacent coils. As shown, there are three similar annular coil sections 8 in the assemblage, but depending upon the heating capacity required, any desired number of coils` 8 may be provided. These coil sections 8 are stacked or superimposed, one upon another, and are firmly interconnected by means of two sets of diametrically opposite special nipples 22 which coact with the adjoining larger bosses 2Ily of the adjacent tubular coils, and these hollow nipples 22 also serve to provide open passages connecting the several chambers 9, see Fig. 3. One of the outer bosses is connected to a heating medium supply pipe 23, while the outer boss 2 0 on the opposite side of the coil assemblage and on the opposite side of the central axis, is connected to an exhaust pipe 24, as illustrated in Fig. 1, and the two remaining outer bosses 20 are closed by pipe plugs 25. The supply and exhaust pipes 23, 24 may communicate with either side of the unit, posed vertically, at the top while tom.` All of the smaller innerbosses 2I are normally sealed by means of standard pipe plugs 26, but the outer-most bosses 2| are provided with special plugs 21 having threaded outer ends projecting through openings in the casing sheets I2, I3 and with which clamping bolts or nuts 28 coact. These special plugs 21 and nuts 28 cooperate with the special nipples 22 to retain the casing and coils firmly assembled, without necessitating the provision of additional clamping bolts.

II which are formed integral with the coil bodies, are all directed inwardly toward the central axis of the unit heater, and these fins cooperate with the casing sheets I2, I3to form passageways constituting a part of the passage I4 for conducting the airthrough The longer fins I0 are arranged in groups and the fins I0 f each group are disposed approximately parallel to each other, although they are in fact separated somewhat farther apart at their outer ends than at the inner ends thereof, in order to permit free entry of the incoming air and to reduce entry losses to a minimum. The shorter iins II arev likewise arranged in groups 2I and are formed to the supply pipe 23 is preferably bosses; and al1 of the fins will provide maximum radiating surface without undesirably obstructing the free iiow of air through the assemblage, and

tical unit heater, comprises but when the assemblage is disthe exhaust pipe is at the botf of vanes or louvers .and toward the fan yripherai suspension lugs 34 y ,l shown in Figs. -5 and 6 may that they may also be readily cast integral with the coils.

While the heat transfer coils 8 are preferably produced by casting, the opposite side sheets I2, I3 of the casing may eitherbe cast or formed of sheet metal and by welding parts together. The central conical portion or depression I1 of the side sheet I2, is adapted to change the direction of the flow of air passing through the unit, from radial to axial, and has a central opening 29 at its smaller end directed away from the motor i6 I5. The depression I1 may also be provided with brackets 30 for supporting the fan motor Iii, and the fan rotor I5 may either be removably attached to the motor shaft 3| by means of bolts 32, or the motor IB may be reversible in operation, so that the ian action may be reversed. The casing sheet the tubular portion I9 forming a duet 33 within which the fan rotor I5 is rotatable, and both of the housing sheets I2, I3 are provided with pewith which vertical suspension rods 35 may be caused to cooperate as shown in Figs. l and 2, when the unit is disposed vertically.

The vortex breaker or diffuser I8 for the veran outer ring which is detachably secured to the tubular portion I9 of the casing sheet I3 by means of bolts or screws 36, a flaring central tube 31 disposed coaxially of the opening 29 and fan I5, and a series of radial vanes 38 connecting the outer ring with the tube 31 so as to prevent excessive swirling of the heated air delivered from the unit. While the diffuser I8 is shown as being metal, it may be built up of sheet metal and the vanes 38 may be made adjustable.

While the diffuser ISand the mode of suspension, is suitable for cooperation with most vertically disposed unit heaters of the improved type, it may also be desirable to suspend the unit from above with its axis horizontal, and to provide for changing the direction of the stream of heated air delivered from the unit heater. In such cases a suspension rig and diffuser such as be provided, and the unit heater assembly remains unaltered except for these two parts. Y

The substitute suspension rig of Figs. 5 and 6 consists of a pair of through bolts 40 coacting with the ears 34 formed on the side plates I2, I3, and a U-shaped clamping member 4I embracing each of the bolts 40 and being adjustably attached to the lower ends of the adjacent suspension rods 42 by means of clampingbolts 43. As shown, the unit heater is suspended with its central axis horizontally disposed, but by releasing the bolts 4I, this unit may be tilted in either direction so that its central axis will assume an oblique angle or even a vertical position. quently be tightened to unit in the desired position of adjustment.

The substitute diffuser 44 of Figs. 5 and 6 consists of an outer ring adapted for attachment to the tubular portion I9 of the casing plate or sheet I3 by means ofthe screws 3 6 and having a series 45 pivotaliy suspended therein by means of friction pins 4l. The louvers 4l may be independently adjusted to any desired position so as to direct the warm air in the desired direction, and also serve as vortex breakers or diffusers for the hot air stream leavingthe heater.

During normal operation of the improved unit heater assemblage, the annular chambers l o! thefinned coils 8 should be constantly supplied I3 is provided with' formed of one piece of castl The bolts'43 may subsefirmly retalnthe heating e iciI of its contact with the -heated fins. The direc- Y but also facilitates construction and assembly of the improved unit heaters, and the fan. I5 and its driving motor are both amply protected against damage by impact and heat. The improved heater assemblage obviously occupies very little space, has no unsightly projections, can be conveniently suspended from above and in any angular position, and can be manufactured and sold at moderate cost.

It should be understood that it is not desired to limit this invention to the exact details of construction or to the precise mode of operation, herein shown and described, for various modications within the scope of the appended claims,`

may occur to persons skilled in the-art. l

I claim: 1. In combination, several similar annular coils concentrically stacked and each having diametriwill effect uniform distribution of the heated air.

In this mannery the improved unit heater will continuously and eiectively heat the air stream, and will deliver a uniformly heated ilow of air to the space which is to be heated. y

The improved unit is extremely simple and compact in construction and flexible in its adaptations, by virtue of the fact that either pipe 23, 2| may be used as an inlet for heating medium, the direction of iiow of the air stream may be reversed either by reversing the motor or the fan,

the diffusers I8, may be interchanged, and the overhead' suspensions may be interchanged. While the suspension rig of Figs. l and 2 is simple and suitable for vertical suspension of the unit, the rig of Figs.` 5 and 6 will permit varied disposition of the heater; and the formation and disposition of the radiating iins I0, II improves the eiliciency by minimizing the air entrance losses and shock, and also prevents overheating of the motor I6 when the unit is idle.

' From the foregoing detailed description it will be apparent that my present invention provides a highly` useful unit heater which is simple, durable, and compact in construction, and which cally opposite bosses coacting with corresponding bosses of the adjacent sections and all provided with alined threaded openings, hollow nipples rigidly connecting said coils at said openings, inlet and exhaust pipes connected to said coils at some of said openings, a casing coacting with said coils to provide an air passage therethrough, and attaching means for said casing providing closures for some of said threaded openings.

2. In combination, several similar coils each having alined bosses on the' opposite sides thereof provided with threaded openings, hollow nipples connecting the adjoining openings of the adjacent coils, pipe plugs closing other of said openings, a casing coacting with said coils to provide an air passage surrounding the latter, and attaching means'for said casing secured to some of said plugs.

is moreover eicient in operation and very flexible in its adaptations. While the assemblage is especially adapted for heating' air, it may also be advantageously used for cooling purposes, and the circular or` annular heat transfer coils can be readily manufactured and assembled in groups of any desired number. The formation and dispositionA of the radiating-fins on the Sections or coils l, not only augments the operating ,emciencm 3. In combination, several similar concentric annular coils each having alined bosses on the opposite sides thereof provided with threaded openings, hollow nipples connecting the adjoining openings or the adjacent coils, a casing coacting with said coils to provide an air passage within which said coils are disposed, and common means for attaching said casing to said Acoils and for sealing some of said threadedopenings.

4. In combination, several similar .concentric annular coils each having alined bosses on the opposite sides thereof provided with threaded openings, hollow nipples connecting the adjoining openings of the adjacent coils, a casing coacting with said coils to provide an air passage within which said coils are disposed, and pipe plugs clossome oi' said openings and having said casing detachably secured thereto.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2486058 *Mar 16, 1945Oct 25, 1949American Machine & MetalsAir drying tumbler for laundry
US2504798 *Feb 9, 1946Apr 18, 1950Young Radiator CoUnit heater
US2564258 *Apr 21, 1950Aug 14, 19518600 Denison CompanyMultiple annular heat transfer element forced flow air heater
US2812925 *May 25, 1956Nov 12, 1957Young Radiator CoOverhead type unit heater
US2814467 *Jun 16, 1954Nov 26, 1957Young Radiator CoUnit-heater motor mounting
US2849023 *May 28, 1953Aug 26, 1958Bendix Aviat CorpCombination valve means
US3469625 *Nov 20, 1967Sep 30, 1969Tydeman Machine Works IncHeat exchanger for cooling liquids
US3960207 *Nov 28, 1973Jun 1, 1976Boer Karl WHeat exchange apparatus
US3978919 *Sep 19, 1974Sep 7, 1976Hans ListCooler-cum-blower assembly for internal combustion engines
US4066047 *Apr 19, 1976Jan 3, 1978International Harvester CompanyToroidal heat exchanger having a hydraulic fan drive motor
US4981171 *Sep 13, 1988Jan 1, 1991Rite Coil, Inc.Heat exchange coil
US6631757 *Aug 7, 2001Oct 14, 2003Ballard Power Systems AgCombined heat exchanger and reactor component
US7798204 *Sep 21, 2010Cyclone Power Technologies, Inc.Centrifugal condenser
US20070056716 *Apr 24, 2006Mar 15, 2007Harry SchoellCentrifugal condenser
U.S. Classification165/162, 165/167, 165/125
International ClassificationF28D1/02
Cooperative ClassificationF28D1/024
European ClassificationF28D1/02C2