US2707811A

US2707811A - Rheostat for aircraft panel light control

Info

Publication number: US2707811A
Application number: US366882A
Authority: US
Inventors: Theodore H Projector
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-07-08
Filing date: 1953-07-08
Publication date: 1955-05-10
Anticipated expiration: 1972-05-10

Description

ited m Pat Ofii 'RHEOSTAT FOR AIRCRAFT PANEL CONTROL Theodore H. Projector, Forest Glen, Md.

No Drawing. Application July 8, 1953, Serial No. 366,882

2 Claims. (Cl. 20-62) (Granted under Title 35, U. S. Code (1952), sec. 266) The present invention relates to rheostats or other electrical components to be used in aircraft instrument panels 01 in other circumstances where panel space is limited.

It is an object of this invention, therefore, to provide a rheostat or potentiometer of the wire-wound type having a small size and compact construction and in which the wire forming the resistance element is smoothly contacted by a moving element with a wiping action.

It is a further object of this invention to provide a rheostat, or other electric component, of the wire-wound type having a moving slider with a pair of contacts, one of said contacts making an electrical connection with the rheostat windings, the other of said contacts moving along a conductive collecting strip.

Another object of this invention is to provide an adjustable rheostat of this character which is operated in an extremely simple and convenient manner and which is susceptible of quantity production with economy and from materials and by means ordinarily available.

It is also an object to provide a variable resistive element which may be used as a rheostat, voltage divider, or

as an ordinary variable resistance.

Generally, in practicing this invention, a slider, having a pair of contacts, is moved by rotation of a threaded or grooved rod which is mounted inside an insulated tubular form. The slider is a conductive collar whose inner surface is machined so as to fit into the spirally grooved rod in such manner that rotation of the rod moves the contact arms along the length of the tube, one of said contacts travelling along a slot in the tube and contacting the turns of a bared wired coil, the other of said contacts travelling along a longitudinal groove and contacting a collecting strip.

Other objects and advantages reside in certain novel features of construction, arrangement and combination of parts which will hereinafter be more fully described and Referring to the drawings it will be seen that the rheostat comprises a tubular form 11, composed of an insulating material. The form 11 is provided with a longitudinal slot 28, and a longitudinal groove having a conductive collecting strip 12 therein. A rheostat winding 10 is wound on the form 11, the windings 10 being bared on the bottom surface, or at least on the surface directly opposite the slot 28. An actuating rod 13 provided with a spiral groove 14 is supported within the form 11.

The form 11 is mounted on the support member 16 on which is provided an integral screw member 19 and a locking nut 18 used for locking the rheostat in position ill) 2,707,811 Patented May 10, 1955 26 by as insulated bearing member 27 and at its rather end by the journal 29. The actuating rdd is also are: vided with a knob or handle 17 for facilitating manual rotation.

A slider 15 is mounted on the actuating rod 13. The slider 15 is a conductive collar, the inner surface of which is machined so as to fit onto the spiral grooves 14. The slider 15 is provided with a spring contact 21 adapted to ride on the conductive strip 12, and a spring contact 20 adapted to move within the slot 28 and to wipe across the bared turns of the winding 10. The slider 15 is also provided with a lug 22 which rides in the slot 28 and prevents rotation of the slider.

The electrical terminals 23 and 25 are provided at each end of the winding 10 while a terminal 24 is provided at the collecting strip 12.

Thus, when the rod 13 is manually rotated by the knob 17, the slider 15 will be caused to travel along the rod and the contacts 20 and 21 will wipe the windings 10 and the collecting strip 12. By connecting a source of potential across the terminals 23 and 25, and by employing the terminals 24 and 25 as output terminals the instrument may be satisfactorily employed as a voltage divider, the output of the divider being determined by the position of slider 15, the output being tapped from the winding 10 by the contact 20 to the conductive slider 15 and to the contact 21, the conductive strip 12, and to the terminal 24.

The instrument may also be employed as a simple variable resistor by merely connecting the terminals 24 and 25 in a circuit to be controlled, a circuit then being completed from the terminal 25 through a portion of the winding 10, the contact 20, the slider 15, the contact 21, the conductive strip 12 and to the terminal 24.

It is also clear that the actuating rod 13 may be provided with a variable pitch groove or thread to obtain a non-linear output.

While I have shown and described a rheostat in which the invention may be advantageously embodied, it is to be understood that this construction has been selected merely for the purpose of illustration and that various changes in size, shape and arrangement of parts may be made without departure from the spirit or scope of this invention.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

I claim:

1. A variable electrical component comprising a hollow cylindrical insulated form having a longitudinal slot therein and having a longitudinally disposed conductive collecting strip mounted on the inner surface thereof; a continuous winding wound on said form; a spirally grooved actuating rod supported longitudinally within said form; a slider mounted on said rod, said slider comprising a conductive collar having an inner surface adapted to fit said spirally grooved actuating rod; a first spring contact on said slider adapted to contact said collecting strip; a second spring contact on said slider adapted to wipe said winding above said slot; means for rotating said rod; and additional means on said slider cooperating with said longitudinal slot to prevent rotation of said slid-er.

2. A variable electrical component comprising in combination a hollow cylindrical insulated form; a longitudinal slot in said form; a conductive collecting strip mounted along the length of the inner surface of said form; a screw mounted within said form for rotation in either direction; an internally threaded conductive collar lar adapted to contact said collecting strip; a second spring contact on said collar adapted to extend through said longitudinal slot in said form; a length of wire spirally wound on said form, said wire having its portions opposite said slot bare of insulation; and a lug fixed to said collar and projecting into said longitudinal slot for preventing rotation of said collar.

References Cited in the file of this patent UNITED STATES PATENTS Cederquist Oct. 7, 1924 Collins Aug. 9, 1932 FOREIGN PATENTS Great Britain Jan. 28, 1926