US3571562A

US3571562A - Terminal assemblies for electric heating elements

Info

Publication number: US3571562A
Application number: US818276A
Authority: US
Inventors: Donald M Cunningham
Original assignee: Emerson Electric Co
Current assignee: Emerson Electric Co
Priority date: 1969-04-22
Filing date: 1969-04-22
Publication date: 1971-03-23
Anticipated expiration: 1988-03-23

Abstract

A plug-in terminal assembly for an electric heating element supported in an opening in a stove top, the assembly comprising a rigid sheet metal bracket straddling a dielectric terminal block, and a connecting member of spring sheet metal straddling the bracket and having a top connected to the bracket and formed with a spring loop extension which terminates in an ear connected to the stove top adjacent the stove opening. The sides of the connecting member have arm extensions which form grounding springs for grounding the heating element as it is plugged into the dielectric terminal block.

Description

United States Patent 1 3,571,562

[72] Inventor Donald M. Cunningham 3,327,095 6/1967 Hanson 219/451 Pittsburgh, Pa. 3,328,562 6/.1'967 Jasionowski... 219/451 [211 App]. No. 818,276 3,466,427 9/1969 Burger 219/451 [22] Filed Apr. 22, 1969 Primar y Exammer-Marv1n A. Champion 3 gagmed E C Assistant ExaminerRobert A. Hafer 1 Ss'gnee ec Attorney-Williams and Kreske St. LOUIS, Mo.

[54] TERMINAL ASSEMBLIES FOR ELECTRIC HEATING ELEMENTS 11 Claims, 7 Drawing Figs ABSTRACT: A plug-in terminal assemhly for an electric heatmg element supported in an opening in a stove top, the as- UeS. u embly comprising a heet metal bracket traddling a 339/14, 339/65 219/541 dielectric terminal block, and a connecting member of spring [51] Int. Cl. HOlr 3/06 Sheet metal Straddling the bracket and having a top connected [50] Field of Search 339/14; to the bracket d f rmed with a spring loop extension which 219/ 451, 541 terminates in an ear connected to the stove top adjacent the stove opening. The sides of the connecting member have arm [56] References cued extensions which form grounding springs for grounding the UNITED STATES PATENTS heating element as it is plugged into the dielectric terminal 3,92} .414 2/l962 Sand 219/451 block.

PATENTEUMAR23 mm 3,571; 562

' SHEET 1 OF 2 i. 01% INVENTOR. DONALD H.C UNNlNGH AN BY Wm M/VM PATENTEDMARZMHTI 3,571,562

SHEET 2 BF 2 INVENTOR. DONALD H. CUNNINGHAM A Tram/Em TERMINAL ASSEMBLIES FOR ELECTRIC HEATING ELEMENTS BACKGROUND AND SUMMARY In Ammerman et al. US. Pat. No. 3,246,123 (which is assigned to the assignee of the present invention) there is shown a range top heater assembly including a dielectric terminal block having an opening into which the terminals of the heating element were projected for plug-in assembly. The terminal block had a pivotal connection with a sheet metal bracket, and the latter was rigidly connected to the stove top.

In an attempt to reduce costs, the sheet metal bracket was I eliminated and the terminal block was loosely disposed underneath the stove top, requiring that connection and disconnection of the heating element and terminal block be made by grasping one with one hand and the other with the other hand of a person. This was a satisfactory substitute, but the stove manufacturers had a preference for a terminal block mounted to the stove top so that only one hand of the housewife is needed to plug or unplug the heater.

Although the pivot connection of the above-mentioned Ammerman patent was entirely satisfactory, it was considered in some instances to be too costly, and in addition required too much vertical space beneath the stove top. Therefore various attempts were made to solve the requirements of the stove manufacturers. One, for example, was to connect the terminal block to a sheet metal bracket, and form the latter with a tongue which was screw connected to the stove top adjacent the opening therein. This did not prove successful since the rigid connection prevented vertical swinging of terminal block and made it difficult to plug the heater terminals into the terminal block and, if the plug-in connection was made, it was usually accomplished by a deformation of the connecting tongue.

My invention overcomes the difficulties noted above while meeting the requirements of the stove manufacturers for safety, convenience and cost, and it is a primary object of my invention to provide new and novel constructions for the purpose aforesaid.

DESCRIPTION OF THE DRAWINGS In the drawings accompanying this description and forming a part of this specification, there is shown, for purposes of illustration, an embodiment which my invention may assume, and in these drawings:

FIG. I is a fragmentary vertical sectional view, with the electric heater unplugged, showing a preferred embodiment of my invention;

FIG. 2 is a horizontal section corresponding to the line 2-2 of FIG. I;

FIG. 3 is an enlarged, perspective view of a bracket used in the illustrated embodiment;

FIG. 4 is an enlarged, perspective view of a terminal block for use with the bracket;

FIG. 5 is a top plan of the terminal block, drawn to a reduced scale;

FIG. 6 is an enlarged, perspective view of a connecting member for use with the bracket; and

FIG. 7 is a view similar to FIG. 1 but showing a slightly different type of connection between the bracket and stove top.

DESCRIPTION OF PREFERRED EMBODIMENT The electric heating element is only fragmentarily shown and may be of the form illustrated in the aforementioned Ammerman patent. Briefly, the heating element is a metalsheathed unit having a flat heating portion (not shown) formed by a series of spiralled convolutions, the ends of the heating portion providing juxtaposed terminal portions 10-10 in the usual manner. Extending outwardly of the sheathed terminal portions are terminals II which are connected to opposite ends of the resistance coil which is disposed within the active heating portion. In order to maintain the terminal portions ill-Ill in fixed spaced relationship, a metal plate 12 is connected thereacross.

The stove top 114, as seen in FIG. I, is provided with an annular downwardly extending lip I5 which defines the opening in the stove top. A combined trim ring and reflector 16 is supported from the stove top, as shown, and has an opening ,17 in its sidewall to pass the terminal portions 11-11 and connecting plate I2.

The electrical terminals 11 of the electric heating element are adapted to be projected through an opening 18 (see FIG. 4) in a dielectric terminal block 19 for plug-in connection with terminal members 20 of any desired construction and which are housed in the terminal block and connected to a source of electrical energy by means of conductors 21. The terminal block is here shown as an elongated dielectric body having cavities for housing the terminal members 20-20, which cavities communicate with the opening 18 at the front end of the terminal block. A pair of rectangularly shaped bosses 22-22 extend from opposite sides of the terminal block at the front end thereof.

The bracket 25 is formed of rigid sheet metal and includes sidewalls 2626 and a connecting top wall 27. The bottom of the bracket is largely open, as seen in FIG. 3. Each of the sidewalls is formed with a rectangular opening 28 which, in horizontal dimension closely receives the horizontal extent of a respective boss 22. The openings 28 are greater in vertical dimension than the vertical extent of the bosses.

The terminal block 19 is assembled with the bracket by disposing it beneath the bracket with the bosses 22 vertically aligned with the openings 28. Lateral pressure of sufficient amount is then exerted against the terminal block and/or bracket to cause the sidewalls 26-26 to spring apart slightly to provide clearance for the bosses, and the latter ultimately snap into the recesses and thus hold the block and bracket assembled. Since the bracket openings are of greater vertical dimension than the bosses, the terminal block may move vertically relative to the bracket an amount defined by abutment of the top of the block with the underside of the bracket top wall and by abutment of the lower edge portions of the bosses with the margin 28a of the bracket openings 23.

The forward lower portions of the sidewalls 26 are provided with inturned feed 29 which act as targets and directing members for the terminals ll1-ll of the electric heating element. As seen in FIG. I, the bracket 25 is largely hidden from view of the housewife and therefore the feet 29, which are visible through the opening 17 in the reflector 16, provide a means for locating a line of projection of the terminal portions 10. Each of the feet 29 has an upwardly curved rear portion 30 to move the terminals upward for proper entry into the opening I8 into the terminal block I9.

A connecting member 35 is provided for resiliently connecting the bracket 25 to the stove top and, in the presently disclosed embodiment, this member is made of spring sheet metal, such as thin stainless steel having the requisite hardness and resiliency to withstand repeated bending operations without breaking or acquiring a set.

The connecting member 35 is formed with sides 36 joined by a top 37, and stiffening ribs 53 may be formed in these parts to increase rigidity where no flexing occurs. The sides 36 and top 37 are so formed as to closely overlie sidewalls 26 and top wall 27 of the bracket 25', and a single rivet 38 is passed through aligned holes 39-40 and headed over to maintain the bracket and connecting member in assembled relation.

The top wall 37 of the connecting member 35 has a forward extension ll of reduced width, the extension merging with a spring loop 42 and terminating in an upwardly extending tab 43 which is of further reduced width, to provide a pair of ears 4M4 which are at an angle with respect to the tab. Extending forwardly from each side 36 of the connecting member is an integral arm 45, having stiffening ribs 54, the arms cooperating to form spaced grounding springs for engagement with the spacing plate 12 extending across the terminal portions III-Ill. It will be noted that the bracket sidewalls 26 are recessed at 36 to provide a marginal abutment 47 for interengagement with a shouldered portion 48 on the connecting member, to maintain alignment between the parts.

The tab 63 is provided with a hole 49 to pass the threaded shank of a screw 50, the shank being threaded into a hole in the lip 115 of the stove top. in this position of parts, the ears d s-Ml engage spaced parts of the undersurface of the lip to restrict rotation of the connecting member 35 and the bracket 25 carried hereby. The bracket is formed with an upwardly extending finger B, the terminal end of which engages the undersurface of the stove top for steadying purposes.

As seen in FIG. il, the heating element is moved toward assembled relation at an angle to the horizontal as suggested by the line A. The trim and reflector 1d obscure view of the bracket, but the feet 29 are visible through the opening 17 and provide a good target for aiming the terminals 11-41 of the heating element. When the terminals strike the feet 29, further inward movement of the heating element causes the terminals to be cammed along the feet and upwardly by the curved rear portions 30 for proper entry into the terminal block opening M3. The heating element may now be moved downwardly to seat on the ledge 52 of the member 16 in the usual manner. As the heating element is moved to assembled position, the connecting plate 12 will span the spring arms @5-45 to ground the heating element through the stove. Preferably, grounding is accomplished before the terminals engage the terminal member 2%) within the terminal block. As seen in FIG. 1, each of the spring arms 35 has a portion disposed behind an ear 55 formed on the bracket 25. The ears form stops which restrict movement of the arms in a direction away from each other and therefore insure good electrical contact between the arms 45 and the plate 12 on the heating element.

Referring to FIG. 7, a slightly different construction is illustrated to accommodate the structure hereinbefore disclosed for use with a stove top of a design wherein the trim ring is built into the top. Most of the parts are the same as those hereinbefore described and will be given the same reference numerals.

The exception is found that the extension 41 of the top wall 37 of the connecting member is provided with a more pronounced loop 6t) and the tab 61 (corresponding to the tab 43) is disposed horizontally to overlie an annular horizontal ledge 62 formed integral with an annular wall 63 extending downwardly from the stove top.

lclaim:

i. in a terminal assembly for an electric heating element which is supported in an opening in a stove top, and wherein the element has terminals which plug into a dielectric terminal block, and wherein the latter comprises an elongated dielectric body having an opening at its front end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said front end, the improvement comprising:

a bracket of rigid sheet metal and having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, each of said sidewalls having an opening therein into which respective terminal body bosses are disposed by insertion of said dielectric body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and said terminal body;

a member for connecting said bracket to said stove top, said member being formed of spring sheet metal and having spaced sides and a top closely overlying respective side and top walls of said bracket, the top of said connecting member being connected to the top wall of said bracket and said top having an extension formed with a spring loop and terminating in an ear adapted to be connected to said stove top adjacent to the opening therein; and

said connecting member having an arm extending forwardly from each of its sides, said arms cooperating to form spaced grounding springs which are engaged by said heating element when the latters terminals are moved into plug-in relation in the opening of said dielectric body.

2. in a terminal assembly for an electric heating element supported in an opening in a stove top, wherein the element has terminals which plug into a dielectric terminal block, the improvement comprising a bracket of rigid sheet metal connected to said terminal block, and a resilient sheet metal support for said bracket, having a portion connected to said bracket and a portion adapted to be connected to said stove top, said support having a horizontally disposed spring loop between said portions so that said terminal block is held by the resilient support of said spring loop in a predetermined position but may be moved vertically therefrom in the operation of plugging said terminals into said terminal block through the resiliency of said spring loop.

3. in a terminal assembly for an electric heating element which is supported in an opening in a stove top and wherein the element has terminals which plug into a terminal block, and wherein the latter comprises a dielectric body having an opening at one end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said one end, the improvement comprising:

a bracket formed of rigid sheet metal having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, said bracket being open at its underside, each of said walls having an opening therein into which respective terminal body bosses are disposed by insertion of said terminal body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and said terminal body;

each of said sidewalls having a foot extending angularly and inwardly from its lower margin in a direction one toward the other to form a pair of guides for vertically directing respective heating element terminals toward the terminal body opening; and

means for connecting said bracket to said stove top.

4. In a terminal assembly for an electric heating element which is supported in an opening in a stove top and wherein the element has terminals which plug into a terminal block, and wherein the latter comprises a dielectric body having an opening at one end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said one end, the improvement comprising:

a bracket formed of rigid sheet metal having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, said bracket being open at its underside, each of said sidewalls having an opening therein into which respective terminal body bosses are disposed by insertion of said dielectric body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and terminal body; and

means for connecting said bracket to said stove top, including a horizontally disposed resilient loop for supporting said bracket and for affording relative vertical movement between said bracket and stove top.

5. The construction of claim 4 wherein said connecting means is formed of spring sheet metal, with one portion connected to said bracket and other portion adapted to be connected to said stove top adjacent to the opening therein, said loop being formed intermediate said portions.

6. In a terminal assembly for an electric heating element which is supported in an opening in a stove top, and wherein the element has terminals which plug into a dielectric terminal block, and wherein the latter comprises a dielectric body having an opening at one end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said one end, the improvement comprising:

a bracket formed of rigid sheet metal and having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, said bracket being open at its underside, each of said sidewalls having an opening therein into which said respective terminal body bosses are disposed by insertion of said dielectric body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and terminal body; each of said sidewalls having a foot extending angularly from its lower portion and in a direction one toward the other to form guides for vertically directing the heating element terminals toward the terminal body opening; and

means for connecting said bracket to said stove top, formed of spring sheet metal with one portion connected to said bracket and another portion connected to said stove top adjacent to the opening therein and constructed and arranged to provide for relative movement largely in a vertical direction between said bracket and stove top,

said connecting means having spaced ears extending from said other portion, said ears being adapted to engage with spaced surfaces of and at the stove opening to restrict turning action of said connecting means.

7. In a terminal assembly for an electric heating element which is supported in an opening ina stove top, and wherein the element has terminals which plug into a dielectric terminal block, and wherein the latter comprises a dielectric body having an opening at one end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said one end, the improvement comprising:

a bracket formed of rigid sheet metal and having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal .body, said bracket being open at its underside, each of said sidewalls having an opening therein into which said respective terminal body bosses are disposed by insertion of said dielectric body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining as sembly of said bracket and terminal body;

each of said sidewalls having a foot extending angularly from its lower portion and in a direction one toward the other to form guides for vertically directing the heating element terminals toward the terminal body opening;

means for connecting said bracket to said stove top, formed of spring sheet metal and having spaced sides and a top wall adapted to lie along respective side and top walls of said bracket, a connection between the top wall of said connecting means and the top wall of said bracket;

a connection between an extension of the connecting means top wall and said stove top adjacent to the opening therein; and

said connecting means being constructed and arranged to provide relative movement, largely in a vertical direction, between said bracket and stove top.

8. The construction of claim 7 wherein an arm extends from each side of said connecting means, the arms cooperating to form spaced grounding members which are engaged by said heating element when the latters terminals are plugged into said dielectric body.

9. The construction of claim 7 wherein a spring loop is formed in said top extension.

10. The construction of claim 8 wherein movement of said arms in a direction away from each other is restricted by engagement of each arm with a respective ear carried by said bracket.

11. The construction of claim 9 wherein the connection to the stove top is effected by a single fastener and wherein an ear extends from opposite sides of said connecting means for engagement with spaced portions of the stove top to restrict rotation of said connecting means about said fastener.

Claims

1. In a terminal assembly for an electric heating element which is supported in an opening in a stove top, and wherein the element has terminals which plug into a dielectric terminal block, and wherein the latter comprises an elongated dielectric body having an opening at its front end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said front end, the improveMent comprising: a bracket of rigid sheet metal and having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, each of said sidewalls having an opening therein into which respective terminal body bosses are disposed by insertion of said dielectric body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and said terminal body; a member for connecting said bracket to said stove top, said member being formed of spring sheet metal and having spaced sides and a top closely overlying respective side and top walls of said bracket, the top of said connecting member being connected to the top wall of said bracket and said top having an extension formed with a spring loop and terminating in an ear adapted to be connected to said stove top adjacent to the opening therein; and said connecting member having an arm extending forwardly from each of its sides, said arms cooperating to form spaced grounding springs which are engaged by said heating element when the latter''s terminals are moved into plug-in relation in the opening of said dielectric body.

3. In a terminal assembly for an electric heating element which is supported in an opening in a stove top and wherein the element has terminals which plug into a terminal block, and wherein the latter comprises a dielectric body having an opening at one end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said one end, the improvement comprising: a bracket formed of rigid sheet metal having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, said bracket being open at its underside, each of said walls having an opening therein into which respective terminal body bosses are disposed by insertion of said terminal body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and said terminal body; each of said sidewalls having a foot extending angularly and inwardly from its lower margin in a direction one toward the other to form a pair of guides for vertically directing respective heating element terminals toward the terminal body opening; and means for connecting said bracket to said stove top.

4. In a terminal assembly for an electric heating element which is supported in an opening in a stove top and wherein the element has terminals which plug into a terminal block, and wherein the latter comprises a dielectric body having an opening at one end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said one end, the improvement comprising: a bracket formed of rigid sheet metal having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, said bracket being open at its underside, each of said sidewalls having an opening therein into which respective terminal body bosses are disposed by insertion of said dieLectric body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and terminal body; and means for connecting said bracket to said stove top, including a horizontally disposed resilient loop for supporting said bracket and for affording relative vertical movement between said bracket and stove top.

6. In a terminal assembly for an electric heating element which is supported in an opening in a stove top, and wherein the element has terminals which plug into a dielectric terminal block, and wherein the latter comprises a dielectric body having an opening at one end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said one end, the improvement comprising: a bracket formed of rigid sheet metal and having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, said bracket being open at its underside, each of said sidewalls having an opening therein into which said respective terminal body bosses are disposed by insertion of said dielectric body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and terminal body; each of said sidewalls having a foot extending angularly from its lower portion and in a direction one toward the other to form guides for vertically directing the heating element terminals toward the terminal body opening; and means for connecting said bracket to said stove top, formed of spring sheet metal with one portion connected to said bracket and another portion connected to said stove top adjacent to the opening therein and constructed and arranged to provide for relative movement largely in a vertical direction between said bracket and stove top, said connecting means having spaced ears extending from said other portion, said ears being adapted to engage with spaced surfaces of and at the stove opening to restrict turning action of said connecting means.

7. In a terminal assembly for an electric heating element which is supported in an opening in a stove top, and wherein the element has terminals which plug into a dielectric terminal block, and wherein the latter comprises a dielectric body having an opening at one end into which said terminals are projected and having bosses extending from opposite sides of said body adjacent to said one end, the improvement comprising: a bracket formed of rigid sheet metal and having spaced sidewalls and a connecting top wall to closely overlie the sides and top of said terminal body, said bracket being open at its underside, each of said sidewalls having an opening therein into which said respective terminal body bosses are disposed by insertion of said dielectric body through the open underside of said bracket and by slightly springing said sidewalls away from each other, said bosses fitting within said sidewall openings and maintaining assembly of said bracket and terminal body; each of said sidewalls having a foot extending angularly from its lower portion and in a direction one toward the other to form guides for vertically directing the heating element terminals toward the terminal body opening; means for connecting said bracket to said stove top, formed of spring sheet metal and having spaced sides and a top wall adapted to lie along respective side and top walls of said bracket, a connection between the top wall of said connecting means and the top wall of said bracket; a connection between an extensioN of the connecting means top wall and said stove top adjacent to the opening therein; and said connecting means being constructed and arranged to provide relative movement, largely in a vertical direction, between said bracket and stove top.

8. The construction of claim 7 wherein an arm extends from each side of said connecting means, the arms cooperating to form spaced grounding members which are engaged by said heating element when the latter''s terminals are plugged into said dielectric body.