US1757043A - Rheostat - Google Patents

Description

A. HALL May 6, 1930.

RHEOSTAT Filed July 5. 1929 JnUQTUE-I": vqrthur Hall 5.9 Jilly Patented May 6, 1930 UNITED STATES PATENT OFFICE ARTHUR HALL, on OAK PARK, ILLLINOISMASSIGNOR 'ro YAxLEY MANUFACTURING COMPANY, or CHICAGO, ILLINOIS, A CORPORATION or ILLINOIS RHEOSTA'I Application filed July 5,

the circular walls of containing cups and has I for its object the provision of an improved assemblage of the bearing for the shaft of such a .rheostat with the end wall of such a containing cup. In practicing my invention inwardly extending prong or prongs are stamped from the end wall of such a cup. These prongs are equidistant from the center of the cup. They are clinched into holding engagement with a flange which is provided upon one end of a bearing sleeve for the shaft of the rheostat, this sleeve end being 1 bottomed upon said cup end wall. This flange is desirably polygonal so as to prevent the bearing sleeve from being turned upon its axis, whileat the same time maintaining the bearing sleeve perpendicular to the cup end wall. a

I will explain my invention more fully by reference to the accompanying drawing in which Fig. 1 is a front view of the rheostat constructed in accordance with the preferred form of the invention; Fig. 2 is a sectional view on line 2-2 of Fig. 1; and Fig. 3'is a sectional view on line 33 of Fig. 2.

The rheostat illustrated is inclusive of a resistance unit that employs a ribbon or strip of insulation 1 about which is wound the resistance 2 of wire, such ribbon thus constituting the core of the resistance. Terminals 3 and 4 are mechanically assembled with the resistance coreand are electrically connected, respectively, with the ends of the resistance winding. A liner 5, also in the form of a strip or ribbon of insulation, encloses the resistance unit. This liner is also in the form of a split ring to permit of its expansion. The parts 1, 2. and 5 are disposed within a metallic cup, these parts being surrounded by thewcircular cup wall 6. The'em'ployment of metal in the formation of the cup makes the employment of the liner 5 desirable. Where the liner and a cup of metal are employed, the liner is desirably continued along the bottom of the cup so as there also to insulate the resistance wire from the cup, Fig. 2.

The ends of the ring 1 are desirably spaced apart in the circle of the ring. A spreading 1929. Serial No. 376,106.

device 7 operates upon-the ends of the core to expand this core circumferentially, that is, n a generally circular direction, as set forth In my copending application Serial 7 No. 376,105 filed July 5, 1929.

The cup is provided with a hub portion 8 that is coaxial therewith. This hub portion constitutes a bearing for the shaft 9-upon which the rheostat arm 10 is mounted, this rheosta't arm riding upon and having electrical contact with the adjacent edge of the hearing against the inner face of the end wall of the cup. Said bearing sleeve is provided with a reduced threaded extension 8' which passes through a central hole in theend wall of the cup. 11 clamping nut'12 is screwed upon the part 8 and against the outer face of the end wall. of the cup, this end wall being thus clamped between the are firmly clinched over the flange 11 to hold the sleeve from turning. Further to ard against .the turning of the sleeve, the fl nge is desirably hexagonal or of other poly onal contour, the flat sides of the flange eing snugly engaged by the portions 13 that have correspondingly flat flange engaging surfaces. The bearing sleeve is thus not only held from rotation but is held with the axis perpendicular to the end wall of the cup. A

split spring collar 9' holds the shaft 9 from axial movement. 4

Having thus described my invention, I claim;

1. A rheostat structure including a resistance unit; a cup surrounding the resistance unit; a bearing sleeve disposed at the central portion of the cup perpendicularly to the. cup end wall and alsocontained in the cup; a shaft journaled in said sleeve; and a contact arm'upon the shaft and electrically ena gageable with the resistance unit, the end wall of said cup having an inwardly projecting prong which is clinched into engagement with said sleeve.

2. The structure of claim 1 wherein the 5 bearing sleeve is formed with a flange por- 7 tion into engagement with which the prong is clinched.

3. A rheostat structure including a resistance unit; a cup surrounding the resistance 10 unit; a bearing sleeve disposed at the central port1on of the cup perpendicularly to the cup end wall and also contained in the cup;

a shaft journaled in said sleeve; and a. contact arm upon the shaft and electrically eng ga cable with the resistance unit, the end wa 1 of said cup having a plurality of prongs inwardly struck therefrom and equidistant from the center of the cup, said bearing sleeve having a poly onal flange whose sides are v closely engaged by said prongs.

In witness whereof, I hereunto subscribe my name.

ARTHUR HALL.

Images