US973000A

US973000A - Resistance-grid.

Info

Publication number: US973000A
Application number: US46947808A
Authority: US
Inventors: Herbert W Cheney
Original assignee: Allis Chalmers Corp
Current assignee: Allis Chalmers Corp
Priority date: 1908-12-26
Filing date: 1908-12-26
Publication date: 1910-10-18
Anticipated expiration: 1927-10-18

Description

H. W CHENEY,

' RESISTANCE GRID. APPLIGATION FILED DEG. 28, 1908.

973,000. '0 Patented 0ct. 1s,1910.

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Wow/W3 nrrnn STATES PATENT OFFICE.

HERBERT RT-CHENEY, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO ALLIS-CHALMERS COMPANY, A CORPORATION OF NEW JERSEY.

RESISTANCE-GRID.

Application filed December 26, 1908.

To all whom 'it may concern:

Be itknown that I, HERBERT W. CHENEY, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented certain new and useful Improvements in Resistance- Grids, of which the following is a full, clear,

and exact specification.

My invention relates to the construction of resistances for use in electric circuits.

Among the objects of my invention are to obtain strength, durability, compactness, and cheapness of construction.

In addition to providing a resistance possessing superior structural features, the arrangement of the parts is such that they may all be readily assembled and firmly held in a permanent or fixed position except those parts intentionally made movable. In this construction, grids are so formed and assembled that one or more of the grids, comprising the resistance, can be taken out and replaced in case of breakage or injury without much trouble Conspicuous among the features of improvement is the method of reinforcing or stiffening the grids especially when they have become excessively heated and rendered flexible.

In the drawings, Figure 1 is a view of one of the grids embodying my invention; Figs. 9. and 3 are elevations of that shown in Fig. 1; i is a view of a modification of shown in Fig. 1; Fig. 5 is a view of anther modification of which Fig. 6 is the end elevation.

Resistance grids have been made very heavy and bulky in structure in order to withstand jars and tendencies to warp out of shape when excessively heated. The resistance grids shown in these drawings are made light in structure. These grids are made of suitable resistance material in zigzag form, for example, substantially as shown in Fig. 1, so as to reduce into comparatively small space a resistance of considerable length. The resistance grid consists of conductor 10, formed substantially as shown, and having its elements such as 26 and 27 parallel and in integral contact to form a number of end turns such as 11 and 23, the conductor terminating in enlarged ends 12 formed of hooks 13 or holes open on one side. These hooked ends fit over insulated cross rods or bolts of thesuspending frame. The number of grids may vary ac Specification of Letters Patent.

Patented Oct. 18, 1910.

Serial No. 469,478.

{ cording to the desired length of the suspending frame. The end turns of the conductors, t such as 11, 14, 15, 16, 17, and 18, are shaped to provide for the reception of an insulated reinforcing bar 19; for example'they may be hook-shaped.

Referring to Fig. 3, it is readily apparent how the bar'19 is received by the end turns of the conductor, one set, such as 11, 15, and 17, being hooked over in one direction, and the other set, such as 14:, 16, and 18, being hooked over in the opposite direction. The bar 19 is of such dimensions as to cause the pairs of elements, 26 and 27 comprising a pair, to spring outwardly when the bar is put in place, as shown in Fig. 2. The bar is, therefore, tightly clamped. The same reinforcing or stiffening arrangement is used at both ends of the grid. By means of this reinforcing it is possible to use grids which are comparatively frail in structure without having the elements warp to such an extent, when excessively heated, as'to buckle-111') or come in contact with each other.

A slight modification of the above arrangement is shown in Figet. Here only the extreme end turns 20 and 21 are hookshaped, the other end turns only extending up to the top of the insulated reinforcing bar butclamping the same.

In Fig. 5 still another modification is shown. Here the end turns of the conductor, such as 23 and 24, are semi circular in shape to receive a reinforcing bar 25 of circular section. Otherwise the arrangement is substantially the same as that shown in Figs. 1, 2, and 8.

I aim in my claims to cover all modifications which do not involve a departure from the spirit and scope of my invention.

Vhat I claim as new and desire to secure by Letters Patent is 1. A resistance grid comprising a conductor having end turns out of alinement, and an insulated reinforcing bar located between said end turns.

2. I; resistance grid comprising a conductor having end turns out of alinement, and an insulated reinforcing bar located bebeing on opposite sides of said bar.

3. The combination of a resistance grid comprising a conductor having hook-shaped end turns, and an insulated reinforcing bait? located in said. hook-shaped end turns.

tween the end turns, adjacent end turns 4. The combination of a resistance grid comprising a conductor with hook-shaped end turns, and an insulated bar located in said end turns, the elements of said con-' ductor being practically parallel with each other. I

5. The combination of a resistance grid comprising a conductor having hook-shaped end turns, and an insulated reinforcing bar located in said end turns, elements of said conductor being sprung when said bar is placed in said end turns.

6. The combination of a resistance grid comprising a conductor having hook-shaped end turns, and an insulated reinforcing bar, adjacent ones of said end turns being sprung in opposite directions when said bar is set in place.

7. The combination of a resistance grid comprising a conductor having hook-shaped end turns, and an insulated reinforcing bar, consecutive ones of said end turns sprung in opposite directions and alternate ones of said end turns in the same direction when said bar is set in place.

8. The combination of a resistance grid comprising a conductor having end turns, and an insulated reinforcing rod clamped between said end turns, extreme end turns of said conductor being hook-shaped.

9. A zig-zag resistance grid having free end turns, and a single bar forming a mutual bracing medium for supporting said end turns.

10. A zigzag resistance grid having end turns, in combination with a member for bracing said end turns to render the grid rigid, end turns being provided with curved projecting portions partially embracing, said member to retain the latter in position.

In testimony whereof I aiiix my signature, in the presence of two witnesses HERBERT W. CHENEY.

Witnesses:

H. C. CASE,

CHAS. L. BYRON.