US2563167A

US2563167A - Galvanometek support

Info

Publication number: US2563167A
Authority: US
Publication date: 1951-08-07
Anticipated expiration: 1968-08-07

Description

Aug. 7, 1951 c. M. HATHAWAY GALVANOMETER SUPPORT Filed Jan. 15, 1947 Patented Aug. 7, 1951 UNITED STATES PATENT" OFFICE- GALVANO ETER SUPPORT 7 Claude M. Hathaway, Denver, Colo.

Application January 13, 1947, Serial No. 721,801

2 Claims. (01. 17195) The present invention relates to galvanometer 4 elements, and more particularly to a support structure for galvanometer elements of the multi-filar type.

Heretofore the construction of a bi=fil-ar it galvanometer element employed a base with spaced apart posts or supports each having a plurality of slots milled therein. In these slots a relatively flat suspension ribbon was stretched with a mirror or reflecting surface suspended between the two supports by the fiat wire. In the past these supports have been made of ivory with two milled. slots about .004 inch wide. In order to support the mirror in a plane parallel to the supporting base of the element great care must be taken to mill each of the slots exactly the same depth. Care must also be taken to have the corners sharp so as to avoid a radius which might engage the fiat galvanometer wire. Such construction requires a great deal of precision work with careful inspection which makes these posts rather expensive to manufacture. It therefore would be desirable to provide some other form of construction which would obviate some of the disadvantages encountered up to the present time.

In accordance with the present invention the ivory supports of a bi-filar galvanometer may be manufactured much more economically and yet the desired accuracy can be obtained. This is accomplished by mounting a round ivory pin transversely of the slot to support the wire strips so that they will not be bent as is the case in the prior construction.

It therefore is an object of the present invention to provide an improved galvanometer support which is relatively simple and economical to manufacture.

A further object of the present invention is to provide an improved bi-filar galvanometer element support which will permit a greater tension to be applied to the galvanometer wire.

Other and further objects of the present invention subsequently will become apparent by reference to the following description taken in conjunction with the accompanying drawing wherein:

Fig. 1 is a plan view of a bi-filar galvanometer element embodying the present invention;

Fig. 2 is an end view of the element shown in Fig. 1;

Fig. 3 is a detailed end view of one of the support posts shown in Figs. 1 and 2; and

Fig. 4 is a side view of the details shown in Fig. 3.

Referring more particularly to Figs. 1 and 2 of the drawing it will be seen that the galvanom} eter element includes a support plate H which carries at one end a binding post l2 having one extremity extending through an insulating bushing l3. At an intermediate point the support plate II is provided with an aperture [4 which is adapted to receive a galvanometer lens. Adjacent the other end of the plate ii there is mounted a housing l5 having a cap l6.v The housing I5 contains an adjusting element H which acts against a spring l8 which in turn is connected to a bell crank lever l9.

Mounted on one side of the plate I I are a pair of ivory support posts 2! which carry a bi-filar element 22 having a mirror 23' attached in the proximity of the aperture I l. One end of the wire of the bi-filar galvanometer element 22 is connected to the binding post i2. The wire extends then to a pulley 24 carried by the bell crank l9 whereupon the wire returns over the support posts 2| to a fastening stud or post 25. The construotion thus far described is similar to the conventional bi-filar galvanometer now in common use.

In accordance with the present invention, as shown in Figs. 3 and 4, the support posts 2| are provided with parallel milled slots 26 which extend appreciably below the level at which the galvanometer wires 22 are supported. Transversely to and intersecting with the slots 26 a hole 27 is drilled into which is fitted a cylindrical ivory pin 28. The cylindrical ivory pin 28 supports the wires 22 and provides a sharp corner between the walls of the slots 26 and the pin 28. Thus the pin 28 assures parallel level positioning of the wires 22. The pin 28 furthermore has the advantage illustrated in Fig. 4 of reducing the strain on the wire 22 as it passes over the support posts to the pulley or to the binding post and the fastening stud. By reducing the sharpness of the change of direction of the wire a lesser strain is introduced into the wire at the support rod 23 so that if desired a greater tension may be applied to the bi-filar galvanometer wire 22.

While for the purpose of illustrating and describing the present invention, a preferred embodiment has been illustrated in the drawing, it is to be understood that the invention is not to be limited thereby since such variations in the construction employed are contemplated as may be commensurate with the spirit and scope of the invention as set forth in the following claims.

What I desire to protect by United States Letters Patent is claimed:

1. A galvanometer element comprising an elongated base, a pair of spaced apart insulated supports mounted thereon, each support having at its top two parallel recesses and a cylindrical opening arranged transversely to said recesses and intersecting with the lower portion thereof, a cylindrical insulating member fitting into said opening to provide curved support surfaces of equal elevation within said recesses, a fiat wire having its ends fixed adjacent one of said supports and forming a loop intermediate its ends, said wire being positioned in the recesses of said supports, and adjustable means adjacent the other support including a movable pulley for the intermediate loop of said wire for applying tension thereto.

2. A galvanometer element comprising an elongated base, a pair of spaced apart insulated supports mounted thereon, each support having at its top two parallel recesses and a cylindrical opening arranged transversely to said recesses and intersecting with the lower portion thereof, a cylindrical insulating member fitted into said opening to provide curved support surfaces of equal elevation within said recesses, a flat wire having its ends fixed adjacent one of said supports and forming a loop beyond the other of said supports, said wire being positioned in the recesses of said supports whereby the major portion of said wire is arranged in two parallel lines in a common plane, and adjustable means engaging said wire loop for applying tension thereto.

CLAUDE M. HATHAWAY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 973,846 Bendel Oct. 25, 1910 1,933,252 Gent Oct. 31, 1933 2,065,907 Perreault Dec. 29, 1936 2,108,815 Gilli et al Feb. 22, 1938 2,241,284 Walder May 6, 1941 2,368,831 Hathaway Feb. 6, 1945 2,425,408 Williams, Jr., et a1. Aug. 12, 1947 2,465,082 Geiser Mar. 22, 1949