US3155812A

US3155812A - Electric heater construction

Info

Publication number: US3155812A
Application number: US151599A
Authority: US
Inventors: Greenhaus Albert
Original assignee: BERKO ELECTRIC Manufacturing CORP
Current assignee: Marley Wylain Co LLC; BERKO ELECTRIC Manufacturing CORP
Priority date: 1961-11-09
Filing date: 1961-11-09
Publication date: 1964-11-03
Anticipated expiration: 1981-11-03

Description

Nov. 3, 1964 A. GREENHAUS ELECTRIC HEATER CONSTRUCTION 3 Sheets-Sheet 1 Filed Nov. 9, 1961 Nov. 3, 1964 A. GREENHAUS 3,155,812

ELECTRIC HEATER CONSTRUCTION Filed NOV. 9, 1961 3 Sheets-Sheet 2 INVENTO R A: zserrsavww I ATTOR Nov. 3, 1964 A. GREENHAUS- 3,155,812

ELECTRIC HEATER CONSTRUCTION Filed Nov. 9, 1961 m 3 Sheets-Sheet 3 W/W lll United States Patent 3,155,812 ELEQITRHC HEATER CONSTR'UtZTlGN Albert Greenhaus, Fresh li leadows, N.Y., assignor to Berke Electric Manufacturing Corporation, Jamaica, N.Y., a corporation of New York Filed Nov. 9, 1961, Ser. No. 151,599 8 Claims. (Cl. 219345) This invention relates to an electric heater and more specifically to a novel and improved heater and support for the heating element.

In the design and construction of electric heaters and particularly heaters embodying plate-like heating elements such as conductive grass and the like it is important that the element be completely insulated from the heater frame and supported in such a manner that it can expand, contract and even warp slightly without placing undue stress and strain on the element. This is particularly important in the case of conductive glass panel heaters which also require pressure-type electrical contacts for applying electric power to the panel.

This invention overcomes many of the diificulties heretofore encountered in panel type heaters and provides an improved heater construction and a new heating element support that are characterized by their simplicity, relatively low cost, durability and ease of maintenance.

Another object of the invention resides in the provision of a new and improved heater that greatly simplifies the assembly of the components including a heater sub-assembly and an outer frame structure for receiving the sub-assembly.

Still another object of the invention resides in the provision of an improved structure for supporting the heater panel in insulating relationship to associated metal structures and in the case of heater panels, such as conductive glass, for providing pressure electrical contact with the panel.

A still further object of the invention resides in the provision of a novel and improved end channel for panel type heater sub-assemblies to support the heater panel and provide electrical contact therewith.

The above and other objects and advantages of the invention will become more apparent from the following description and accompanying drawings fonning part of this application.

In the drawings:

FIG. 1 is a perspective view of a heater in accordance with the invention;

FIG. 2 is an exploded view of a fragmentary part of the heater sub-assembly showing the cooperation of the heating panel, end channel, reflector and electrical contactors;

FIG. 3 is an exploded perspective view or" portions of the heater frame and sub-assembly;

FIG. 4 is a perspective view of a fragmentary portion of a glass heater panel;

FIG. 5 is an enlarged front elevation of the heater of FIG. 1 with portions broken away;

FIG. 6 is a cross-sectional view of FIG. 5 taken along the line 6-6 thereof.

The illustrated embodiment of the heater utilizes a conductive glass panel having a uniform conductive coating on one side thereof and silver contacting strips on opposing edges. It is understood, however, that the invention is equally useful for other types of panels.

Referring now to the drawings, the heater is generally denoted by the numeral 18 and includes an outer'frarne 11,

end portions

12 and 13, a grill 1d and an inner heater sub-assembly generally denoted by the numeral 15 and comprising a pair of end channels 16, a conductive glass plate 17, contacting members 18 and a reflector 19. The subassembly is a separate unit which may be readily installed in and removed from the outer frame 11. It is also evident that two or more heaters may be placed in end to end relationship in which case a connecting member mechanically joining the meeting ends of the two heaters may be utilized to form, in effect, a single unit of extended length. Moreover the heaters may be of any desired size and wattage ratings.

As pointed out above the sub-assembly forms a separate structural element that may be completely assembled and then installed in the frame 11. In the installation of this heater, the sub-assembly is normally removed from the frame, and the latter is then secured to a supporting surface and the electrical cable installed. The sub-assembly is then connected to the cable and then secured in the housing or frame.

More specifically and with reference to FIGS. 2 and 3, the sub-assembly includes a channel-shaped reflector 19 which has a length substantially equivalent to the length of the frame 11. The upper leg or wall 2% of the re flector 19 is somewhat deeper than the lower Wall 21 and both the walls have their end portions folded back on themselves in order to provide an adequate degree of stiffening. The inside surfaces of the reflector 19 are preferably polished in order to reflect the heat generated by the panel 17 outwardly from the heater. The rear wall 22 of the reflector 19 is provided with a pair of openings 23 and 24 at each end thereof to receive the legs of the end panels 16 as will be described. The upper and

lower walls

29 and 21 of the reflector 19 have openings 25 near the ends thereof for attachment of the end channels 16.

The heater channel 16 in the instant embodiment of the invention comprises a glass plate 26 having a conductive coating 27 on the back side thereof. The ends of the glass panel 26 are each provided with a low resistance conductive strip 23 of silver or other suitable low resistance material which forms an electrical contact 7 with the conductive surface 27 so that energy applied to the two conductive strips 28 will cause the conductive surface 27 and consequently the panel 26 to be heated.

The panel 17 is mounted in the reflector 19 by means of a pair of end channels 16. These end channels are preferably formed of a suitable insulating material capable of withstanding the temperatures of the panel. While any suitable material may be utilized for this purpose, a phenolic resin containing asbestos has been found useful for low temperature heaters. For high temperature heaters it is apparent that other insulating materials such as ceramics or the like may be employed.

Each end channel 16 comprises an essentially rectan gular body 29 having rounded lower or inner corner portions 3d to conform with the configuration of the reflector 19. In addition the body is provided with a pair of legs 31 and 32 which have a Width approximately half the width of the body 29. When each channel is mounted in the reflector the legs 31 and 32 extend through the openings Z3 and 24 in the reflector and the channel is secured in place by a pair of screws 33 which extend through the cooperating openings 25 in the reflector and threadably engage openings 34 in each end wall of the channel.

As will be observed in the drawings each channel is essentially hollow and includes partitioning members to receive and hold the contact structure 18 and the end of the heating panel 17 containing the conductive strip 28. A heating panel receiving and supporting compartment is formed within each end chanel by a pair of inwardly extended coplanar partitioning elements or

members

35 and 36 which are parallel with the top or outer wall 37 and the bottom or inner Wall 33. These partitions form an elongated slot 3) having a width slightly greater than the thickness of the panel 17 and a length slightly greater than the width of the panel 17. In this Way slight distorp 57 of the frame.

tions of the panel in heating and cooling will not unduly stress the panel and cause it to fracture. The contact structure 13 is arranged to be received by and held within the end channel 16, and for this purpose the structure includes a flat strip 46* of conductive material and a bowed spring 41 carrying carbon button contacts 42 on the outer ends thereof. The center of the spring 41 is secured to the strip by rivets 43 or other suitable fastening means. One end of the strip at) is fitted with a connector 44 and a lead Wire 45 is secured to the connector 44.

Retention of the contact structure 18 within the panel 16 is effected by the provision of suitable partitions and stops within the body. More specifically, the partition 36 includes an end wall d6 extending to the wall 38 and having a cutout 47 therein. The cutout has a width approximately equal to the width of the strip 4%} and a height somewhat greater than the thickness of the strip 4t}. A spacing member 48 is carried by the wall 38 and has its outer edge aligned with one edge of the opening 4'7. A stop 49 is disposed between the wall 46 and the adjoining end wall of the body 2), and limits longitudinal movement of the strip itl when placed within the channel 16. 6n the other end of the channel it? there is an L-shaped wali having legs 4% and 54 with the leg or stop 49' extending to the outside wall 51 of the body 29. The leg 54) is generally coincident with the inner edge of the wall 38. An inner spacing member 52 which is seen more clearly in FIG. 6 extends from the partition 35 to the wall 33. The wall 51 of the body 29 includes an opening which is substantially in alignment with the wall 543- for the reception of the lead wire 4:") fastened to the contact structure 13. When the contact structure 18 is in place within the end channel 16 as shown in FIGS. 3 and 6 it is maintained in position by the spacing members 425 and 52, the cutout 47, the wall part and the laterally spaced

stops

49 and 49. The heating panel is inserted in the channel and the contact buttons 42 will be aligned with and press firmly against the conductive strip 28 to make contact with the panel. At the same time, the pressure of the contacts against the panel securely locks the contact structure 18 in place within the channel.

Upon attachment of the channels 16 to the ends of the heating plate 17 the assembly is then placed in the reflector 119 with the legs 31 and 32 extending through the cooperating openings. Screws 33 are then inserted through openings 25 and tightened into cooperating openings in the end channels 15 to complete the fabrication of the sub-assembly. The lead wire which in the instant embodiment of the invention would have a length of two to three feet is then threaded through an opening 53 in the leg 31 which now directs the wire toward the center of the subassembly and causes it to lie 011 the back side of the reflector 19. The sub-assembly 15 further includes a pair of spring clips 54 as shown in PlGS. 3 and 6 each of which has a rounded back portion 55 which lies against the reflector and an opening to receive the upper screw 33 which holds the clip in place. The forward flanged end portion 56 cooperates with a portion of the frame 11 as will be described to hold the sub-assembly lid in place in the frame.

The heater frame Ell comprises an elongated back wall 57, a top wall 53, and a bottom wall 59. The bottom wall further includes a'vertically extending front portion or wall the top edge of which is bent inwardly to form a compound

flange comprising sections

63 and 62. The flanged portion 62 is dropped below the flange portion 6?. to form a shoulder 63. The top-wall dsincludes a front edge portion having a vertically disposed wall section a horizontally disposed wall section Q35 and a reversely formed end portion comprising downwardly and inwardly inclined part as and an inwardly extending portion 67'.

The forwardmost wall portion es of the frame 11 extends beyond from the bottom front wall so that when the 4 grill lid is in place, it is inclined relative to the rear wall trical contact structure therebet-ween, and laterally spaced The rear wall 57 of the frame includes a pair of tabs 68 and each end of the frame which extend inwardly and cooperate with the upper legs 31 of the channels 16 when the sub-assembly is positioned in the frame. In addition, the lip or flange 62 includes a pair of cutouts $9 at each end thereof to accommodate the lower screws 33 on the subassembly structure.

With the invention as described and with the sub-assembly assembled as shown in FIG. 3, the latter is ready to be inserted in the frame 11. To accomplish this the lower edge 21 of the reflector is moved into engagement with the lip 62 on the lower portion of the frame. The sub-assembly at this point is inclined outwardly from the frame. The sub-assembly is then moved completely into the frame by pivoting it about the lower edge of the reflector, and in so doing, the legs 31 and -32 will move backwardly until they lie flush against the back wall 57 of the frame. At this point, the legs 31 of the channels 16 will lie beneath the tabs 68 as will be observed in FIG. 6. The springs 54 during this operation are held in a depressed position to clear the

front edge portions

66 and 67 of the top wall 53. When the sub-assembly is properly positioned within. the frame the springs 54 are released and ride upwardly behind the inwardly extending frame edge 67. The springs hold the sub-assembly tight against the rear wall 5'7 of the frame and the tabs Gil prevent the sub-assembly from being shifted upwardly. In addition, the front edge of the lower wall 21 of the reflector butts against the shoulder 63 011 the frame and the lip or flange 62 provides the support for the subassembly.

The frame 11 may include a number of electrical knockouts for the reception of suitable electric cable connectors, as for instance the connector 7%. The supply c nductors 71 brought in through the connector 7% are attached to the leads 45 to supply energy to the heater. The grill 14 is held in place by upper openings 72 in the upper wall portion 67 and lower openings 73 in the flange portion 61 of the lower frame part.

After assembly of the heater as described, the

end members

12, 13 are placed in position as illustrated and secured to the frame .by screws 74. As previously described heaters of the type described above may be connected in and to end relationship by appropriate coupling members which join the heaters one to the other and form a substantially unitary structure.

While only one embodiment of the invention has been illustrated and described, it is evident that alterations, modifications and changes may be made without departing from the true scope and spirit thereof.

What is claimed is: 1

l. in an electric heater, a sub-assembly comprising a reflector, an electric heater panel having terminal means for the application of energy thereto, and channels of insulating material having openings therein for receiving opposing ends of said heater panel, said terminal means comprising electric contact strips on said opposing ends of said panel, spring loaded electric contact means in each of said channels, said contact means engaging said contact strips and means on said channels for securing said panel to said reflector and retain the channels in engagement with the heater panel, each of said end channels comprising an elongated hollow structure having end walls, top and bottom walls and one side wall, at least one partition between the top and bottom walls to form an elongated panel receiving channel, and'means on said bottom wall receiving and retaining said electrical contact means.

2. An insulated end channel for an electric heater comprising an elongated hollow body having end walls, top and bottom walls and one side wall, a pair of spaced coplanar elements between the top and bottom walls to form an elongated opening for reception of a heater panelbe: tween the elements and said top wall, ,a pair of spaced stops on'said bottom wall for receiving an elongated elecstops on said body to maintain said contact structure in predetermined lateral alignment within said end channel.

3. An insulated end channel according to claim 2 wherein said body includes at least two legs on said bottom wall and extending outwardly therefrom in spaced parallel relationship.

4. An electrical heater comprising a frame having a back wall, a top wall and a bottom wall, with the latter having its forward portion bent upwardly and inwardly to form a bottom channel and an inwardly extending ledge, a subassembly including -a reflector having a rear wall and top and bottom walls, an electric heater panel between the top and bottom reflector walls and spaced from the rear reflector wall, said heater panel having terminal means on opposing ends thereof, a pair of elongated end members of insulating material secured to said reflector and engaging ends of said heater panel, electrical contacts carried within said end members and electrically contacting said terminal means, spacer means extending from said rear reflector wall, said bottom reflector wall resting on said ledge with the spacer means engaging said back frame wall and means carried by said reflector and releasably engaging said frame to hold the sub-assembly therein.

5. An electrical heater comprising a frame having a back wall, a top wall and a bottom wall, with the latter having its forward portion bent upwardly and inwardly to form a bottom channel and an inwardly extending ledge, a sub-assernbly including a reflector having a rear wall and top and bottom walls, .a heater panel between the top and bottom reflector walls and spaced from the rear reflector wall, end members of insulating material secured to said reflector and engaging ends of said heater panel, spacer means extending from said rear reflector wall, said bottom reflector wall resting on said ledge with the spacer means engaging said back frame wall and means carried by said reflector and releasably engaging said frame to hold the subassembly therein, said spacer means form part of said end members and said rear reflector wall includes openings through which said spacer means extend.

6. An electric heater according to claim 4 wherein said back frame wall includes stops extending inwardly thereof and overlying at least certain of said spacer means to restrict upward movement of said sub-assembly relative t said frame.

7. An electric heater according to claim 4 wherein said releasable means includes spring means extending in a forward direction of and engaging the top reflector wall and said top frame wall includes means cooperating with said spring means for holding said sub-assembly in said frame.

8. In an electric heater, a pair of insulated channels positioned in spaced relationship, each of said channels comprising an elongated structure of insulating material having at least two elongated openings in one side thereof, an electrical heating panel including terminal means on opposing ends thereof, each of said opposing ends of said panel extending into one of said openings in one of said elongated structures, spring loaded electric contact means in the other opening in each of said elongated structures and electrically contacting the terminal means on the associated end of said heating panel and means for retaining said heater panel and said elongated structures in engagement one with the other.

References Cited in the file of this patent UNITED STATES PATENTS 2,706,763 Glynn Apr. 19, 1955 2,781,440 Petersen et a1 Feb. 12, 1957 2,795,682 Knoll June, 11, 1957 2,845,527 MoEachron July 29, 1958 2,858,515 Thunander et al Oct. 28, 1958 2,911,6l2 Jackson et al. Nov. 3, 1959 2,995,644 Zellers Aug. -8, 1961 3,015,083 Juris Dec. 26, 196-1 3,026,398 Quirk Mar. 20, 1962

Claims

1. IN AN ELECTRIC HEATER, A SUBASSEMBLY COMPRISING A REFLECTOR, AN ELECTRIC HEATER PANEL HAVING TERMINAL MEANS FOR THE APPLICATION OF ENERGY THERETO, AND CHANNELS OF INSULATING MATERIAL HAVING OPENINGS THEREIN FOR RECEIVING OPPOSING ENDS OF SAID HEATER PANEL, SAID TERMINAL MEANS COMPRISING ELECTRIC CONTACT STRIPS ON SAID OPPOSING ENDS OF SAID PANEL, SPRING LOADED ELECTRIC CONTACT MEANS IN EACH OF SAID CHANNELS, SAID CONTACT MEANS ENGAGING SAID CONTACT STRIPS AND MEANS ON SAID CHANNELS FOR SECURING SAID PANEL TO SAID REFLECTOR AND RETAIN THE CHANNELS IN ENGAGEMENT WITH THE HEATER PANEL, EACH OF SAID END CHANNELS COMPRISING AN ELONGATED HOLLOW STRUCTURE HAVING END WALLS, TOP AND BOTTOM WALLS AND ONE SIDE WALL, AT LEAST ONE PARTITION BETWEEN THE TOP AND BOTTOM WALLS TO FORM AN ELONGATED PANEL RECEIVING CHANNEL, AND MEANS ON SAID BOTTOM WALL RECEIVING AND RETAINING SAID ELECTRICAL CONTACT MEANS.