US1695869A

US1695869A - Heating unit

Info

Publication number: US1695869A
Application number: US218405A
Authority: US
Inventors: Ernest E Sutherland; Frank F Forshee
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1927-09-09
Filing date: 1927-09-09
Publication date: 1928-12-18
Anticipated expiration: 1945-12-18

Description

Patented Dec. 18, 1928.

UNITED "STATES PATENT; OFFICE,

nimnsr E. SU'IHEBLAHD AND FRANK F. FORSHEE, OF MANSFIELD, OHIO, ASSIGNORS OF PENNSYLVANIA.

MANUFACTURING COMPANY, A CORPORATION HEATING UNIT.

Application mo e neptember 9, 1927. Serial in. 218,405. 7

Our invention "relates to electric heating units and more particularly to base plates therefor. a m M object of our invention is tosgirovide a relatively simple, inexpensivean easily manufactured heating umt. I

Another object ofour invention is'to provide a single-piece base-plate embodying side supporting-portions for a refractory resistorsupporting memher, laterally extending end portions embodying, respectivel a handle portion and a terminalwassem ly locatingu means, together with a central depressed heatpreferab y sheet steel, and embodies two parshield portion. l a; 1

In practicing our invention, we provide a unitary 'base plate made .of pressed sheet metal and embo ying spaced side portions located in a central horizontal plane for directly sn porting a refractory plate, laterally exten g end portions, the

intermediate parts of "whiehiare bowedup- .wardl one end portion being provided with r a hen 1e and the other end portion being provided with slots for locatinga terminal-pinsupporting plate, and a central depressed portion constituting a. heat shield for the heating The unitary; base plate alsolaterally extending inte a1 supporting portions for engaging suit le supporting members for the heating unit. I v p In the single sheet of drawings? Figure 1 is a top plan view of a base plate embodying our invention with a refractory plate, shown in part only, located thereon,

heating unit embodying ourinvention,

Fig. 3 is a fragmentar view, in elevation from the handle amigo ,the heating unit, and

assembled heating volition.

An ,eIectric heating -unit 11.; embcdies one a plurality of overhunggrooves in itsupper surface for receiving a helically wound resister 15. Asthe plate itself constitutes no part of our invention, ibis not deemed neces unched' and.

Fig. 2 is a view, in end elevation, of a end portions 0 the member 19 with the inter- Fig. 4 is a view,in side elevatiom oi 8.11 unit embodyingv our insary to illustrate and describe it in further detaiL 7 .Heretofore, relatively heavy cast-metal frames have. been :used as the supporting members for, one or more of the refractory plates 12, but asupporting base plate made of cast metal must be made relatively heav 1n order to obtain suificient' strength with the result'that the frame will have a relatively large heat-storage capacity.

The supporting base plate, more particularly embodying our invention, is made 01 a single ieceo relatively thin sheet metal,

provided with a depending outer flange 23 to constitute a handle by means of WlllCll the heating 1111113 maybe moved into and out of its normal operative position relatively to a device, or appliance, to be heated thereby.

The intermediate portion 22 of the other end member 19 is located insubstantially the same upper plane asgis the portion 21 and constitutes a terminalspin-protecting memher. The inte ral side walls-connecting the mediate portion 22are each provided with slots 24 which extend laterally of the heating unit, substantially asshown in Fig. 1 of the drawings. I I

The member 13 embodiesalso a central depressed portion 25 constituting a heat shield and located in a lower plane than that of the side portion 16.

Openings

26 and 27 are provided in the sheet-metal plate incidental to the punching and shaping portion necessary to change a flat sheet-metal plate tothe form shown in the drawing. The slots or

openings

26 and 27 extend laterally of the member 13, and, therefore. parallel to the end portions'18-and19; Itis obvious that all the side walls of the upwardly bowed portions 21 and 22 must be of substantially the same length as are the side walls of the central portion 25 and'the forming die, or dies, are

so made that when the end portions are bentupwardly and the central portion is bent downwardly, this requirement ofsuhstantial equality in length of the side walls will be met. The depressed portion 25 is bowed downwardly toward the central point in order that itshall not buckle during expansion or contraction oftlieinmnl'nr 18 in-ei.

dent to heating and cooling.

In order to provide inwardly extending lug portions, designated by 28and 29, respectively, the side wall portions ot'ythepart is punched out-by suitable means to the shape shown more particularl-y in-Fig. 1 oftheiri ctoryplate as well. The elongated form.

otthe openings is made necessary by the fact that refractory plates are not exactly uniform but vary because of slightly changing conditions during their; manufacture.

The side-portions 16 andl7jhave depend ing flange port-ions 37 which, in turn, are each provided with outwardly:extending portions 38. The portions 38 are, inturn, provided with a relatively narrow depending flange portions 39 which are ada ted'to restupon suitable supports, such as g ides, provided in the even of electric ranges; By providing the flange portions 39 with an elongated recess l1, illustrated more particularly in Fig. A ofthe drawings. there will be but four points of support for the assembled heating element when located in its proper operative position on the supporting glides. The portions 37 may be provided with elongated openings 42 therein in order'to reduce the amount ofheat. which will traverse the portions .37and the portions 38 and'which might flow from there to the. supporting means.-

l heterminal assembly lat embodies a sheetmetal plate 43, of substantially L-shape, in lateral section, one leg of which is bolted. against the under surfaceofthe intermediate portion 22 by a pluralityof short screws .44 and nuts 4.5. A plurality of terminal pins 46 are insulatedly mounted on the other leg of the member l3. in a mannerwellknown in the art. As shown in the drawings, three such terminal pins are provided to which the ends of the resistor wire 15 are connected in order that a three-heat operation may be effected by a suitable switch (not shown), in a manner well known in the art. The terminal pins 46 extendasuitable distance beyond the outer edge of the portion 22, in order that they may extend into cooperating socket members (not shown) which are connected to a suitable source. of su ply of electric energy.

The device emllodying our invention thus provides a sheet-metal base plate having portions thereof located in three different parallelwemftumling ilmwfl, certain portions of the plate being bent upwardly and another portion ofithe plate being bent downwardly.

The downwardly-bent central portion consth.

tutes a heat shield to reduce the ainount ot'. heat Whichisradiated downwardly from the bottom of'the refractory plates 12. The slots, or openings 24, provide. a convenient. means for receiving the end portionsof the terminal pinssupporting plate in ordeiw to hold it in proper alignment'latexally and longi tudinally of the heatingunit;

The device embodying our. invention thus. provides a singlepiece sheet-metal in se. plate forsupporting one or more refractoryplates.

of electric insulating material in which is mounted a resistor. A. plate ofthis kind is relatively inexpensive aindhns a.relatively small heatstorage. capacity.

Various-modifications may be made in; the device embodying our invention without departing from tlre spirit and scope thereof and we desire, therefore, that only suchlimita' tions shall be placed thereon as are imposed by the. prior art-oi: are specifically setforth in the appended claims.

We claim as our invention:

1. An electric heating unitcomprising a. sheet-metal base platev bent to comprise two spaced sidc-port'ionsanintegral cross mem ber at-oae end slrapml to constitute a han-v die, an integral cross'membemat theother end bent to channel-shape, slote in the side walls of said cross member of channel-shape, a termiIml-su-pporting but having its ends titty ting; into said slots, resistor operetively supported by the two side port-ions only, and {germinal pins in said. terminal-supporting 9. Anelectric heatingunit comprising a refractory plate, a resistor supported thereby, and a -base plate for supporting the refractory ates, said base plate comprising two paralel-extending side portions for directly operatively engaging the refractory plate, integral end port-ions bent upwardly from the plane of the side portions and mm body-mg respectively a handle portion at-one end and a terminal-pinsupporting and protectingportion at the other end, and an integral heatshield bent downwardly from the plane of the side portions.

3. An electric heating unit comprising a refractoryplate, a resistor therein, and a.

unitar sheet-metal base plate comprising a terminal-pin-supporting plate having its two si e portions directly supporting the reends fitting into the slots in one end portion. 10 fractory plate, two integral upwardly bowed In testimony whereof, we have hereunto end portions, one end portion having an insubscribed our names this 31st day of Aug.

5 tegral depending flange to constitute a han- 1927.

dle and the other end portion having slots in the side walls, and a central downwardly- ERNEST E. SUTHERLAND.

bowed portion constituting a heat shield, and FRANK F. FORSHEE.