US2995812A

US2995812A - Method of selectively positioning relay contacts

Info

Publication number: US2995812A
Application number: US700675A
Authority: US
Inventors: George R Bates
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1957-12-04
Filing date: 1957-12-04
Publication date: 1961-08-15
Anticipated expiration: 1978-08-15

Description

Aug. 15, 1961 G. R. BATES 2,995,812

METHOD OF SELECTIVELY POSITIONING RELAY CONTACTS Filed Dec. 4, 1957 United States Patent 2,995,812 METHOD OF SELECTIVELY POSITIONING RELAY CONTACTS George R. Bates, Hinsdale, 111., assignor to Western Electric Company, Incorporated, New York, N.Y., a corporation of New York Filed Dec. 4, 1957, Ser. No. 700,675 3 Claims. (Cl. 29-404) This invention relates to a method of using relay contact positioning tools having cammed surfaces and more particularly to a method of stacking a number of said tools to hold different patterns of relay contacts open during operation of the relay.

In testing a relay having covered banks of contacts, it is quite often necessary to remove the cover and thus expose the contacts to impurities of the surrounding air. Due to the delicate nature of relay contacts, testing tools must be able to engage, move and hold the contacts without damage thereto.

Also, in positioning relay contacts for test purposes, it is highly desirable to prevent any actual physical contact between the tool used to open the relay contacts and the conducting surfaces of the contacts. Any insertion of a tool between the conducting surfaces of the relay contacts enhances the chance of inducing impurities between the engaged surfaces which may result in sticking of the contacts.

An object of the invention resides in a method of stacking cam faced tools to establish a preconcerted configuration of cam surfaces and utilizing the stacked tools to selectively position a bank of relay contacts.

With this object in view, the present invention contemplates inserting tools in groups through a slot in a transparent relay contact cover. The tools have cam portions on the sides thereof in predetermined patterns to open and position relay contacts.

The tools are used in combination with one another to provide varied patterns of cam surfaces to open any desired combinations of relay contacts of a given relay bank. The tools are insertable to any depth and are constructed thin enough to provide the insertion of the tools in stacked relation. The transparent relay cover has slots therein which allow for insertion and visible checking of the position of the tools with respect to the relay contacts.

Other objects and advantages of the present invention, will be apparent from the following detailed description when considered in conjunction with the accompanying drawings, wherein:

FIGS. 1 and 2 are perspective views of tools having different cam arrangements formed therein for carrying out the principles of the present invention;

FIG. 3 is a sectional view of a relay contact cover showing a typical tool inserted through the cover and into a closed relay bank with one pair of contacts thereof cammed open by the tool;

FIG. 4 is a sectional View of a relay contact cover showing two tools in stacked relation inserted through the relay contact cover and into a closed relay bank to open two pairs of contacts of the relay bank;

FIG. 5 is a sectional View along line 5-5 of FIG. 3 showing the tool inserted in a closed relay bank to open a pair of contacts thereof; and

FIG. 6 is a cross-sectional view along line 66 of FIG. 4 showing two typical tools inserted through the relay contact cover and into a closed contact bank opening selected contacts thereof.

Referring to FIGS. 36, there is shown a portion of a relay having two banks of relay contacts 2024 and 2529. A transparent cover 35 having two oppositely disposed slots 36 is placed over the relay contacts and is secured to the relay. The transparent cover acts to protect the relay contacts from exposure to the surrounding atmosphere. A row of stationary contacts 31 are positioned between the two banks of movable relay contacts. A card 30 made of suitable dielectric material is placed between the stationary contacts 31 and the movable contacts 2029. Armature 33 operated by the relay windings (not shown) and positioned within the openings 32 of card 30 move the card from left to right to alternately open and close the relay banks 2024, 25-29.

Referring to FIG. 1, there is shown a tool 40 for carrying out the present invention made of any suitable resilient dielectric material. A body 41 of the tool has a tapered or wedge-shaped end 42 and cam 43 projecting from one side of the body 41. Tool 40 (FIGS. 3 and 5) is inserted through either slot 36 in the transparent cover 35. The tool 40 is moved between the closed relay bank 2024 and the supports 34 for the stationary contacts 31. The cam 43 on the tool 40 moves a pair of relay contacts 23 from the closed position to the position indicated without any contact of the tool with the abutting surfaces of the relay contacts.

In FIG. 2, there is shown another tool 50 made of suitable dielectric material having a body 51 and tapered ends 52. The body 51, as shown, has earns 53 and 54 projecting from the side thereof. One cam 54 extends along the body 51, a distance equal to or greater than the distance between two pair of relay contacts and the other cam 53 is smaller so as to only span a distance suflicient to engage one pair of contacts at a time.

Referring to FIGS. 4 and 6, card 30 has been moved to the left by armature 33. The card in this position opens relay bank 2024 and closes relay bank 25-29. Tool 40 is inserted through a slot 36 of the transparent relay cover 35 and is moved between the closed relay contact bank 2529 and the supports 34 of the stationary contacts 31. Cam 43 of the tool 40 causes the contacts 26 to move away from the associated stationary contact 31. An additional tool 50 is then inserted in stacked relation to tool 40 and in the same manner as tool 40 to open pairs of

contacts

28, 27 and 25. Contacts 27 and 28 are opened by the elongated single cam 54 and contacts 25 are opened by the other smaller cam 53. The tools 40 and 50 could be placed in stacked relationship prior to insertion in the slot 36 and more than two tools could be utilized to obtain other patterns of selectively opened contacts. The tools 40 and 50 also may be moved relative to each other to vary the pattern of contacts to be opened for testing.

It is to be understood that there are alterations that can be made in arrangement and shape of the cams 43, 53 and 54 and that a multiplicity of tools 40' can be used in stacked relation to obtain any desired pattern of opened and closed contacts in the relay contact bank. Further, it is to be understood that one tool 40 could be inserted through one slot 36 and a second tool could be inserted through the oppositely disposed slot to obtain a selected positioning of the relay contacts.

It is to be understood that the above-described arrangements of apparatus and construction of elemental parts are simply illustrative of an application of the principles of the invention and many other modifications may be made without departing from the invention.

What is claimed is:

1. A method of selectively positioning a bank of relay contacts in accordance with a predetermined pattern which comprises, inserting a tool having a cam surface on the side thereof so as to engage predetermined contacts at points other than their abutting surfaces and thereby open said contacts, and then successively inserting additional tools in juxtaposition of the first tool so as to engage additional contacts at points other than their abutting surfaces and thereby open further contacts to establish said predetermined pattern.

2. A method for selectively positioning relay contacts, comprising inserting a first tool having a predetermined configuration into a relay bank to engage predetermined contacts thereof at points other than their abutting surfaces to thereby open said contacts, inserting an additional similar tool in juxtaposition of the first tool to engage other predetermined contacts of the relay at points other than their abutting surfaces to thereby open said other contacts, and moving the tools Within the relay bank to selectively change the pattern of contacts to be opened.

3. The method of selectively positioning a plurality of relay contacts in a predetermined pattern in a relay bank, which method comprises inserting a tool having a cam surface on one side thereof into the relay bank to engage predetermined contacts at points other than their contacting surfaces and thereby to position the predetermined contacts out of their normal position, inserting another tool having a cam surface on one side thereof into the relay bank in juxtaposition to the first tool to engage other predetermined contacts at points other than their contacting surfaces and thereby to position said other predetermined contacts out of their normal position, and then moving the tools independently of each other Within the relay bank to selectively engage different contacts and thereby to change the pattern of the contacts which are positioned by the tools.

References Cited in the file of this patent UNITED STATES PATENTS 1,171,320 Chroninger Feb. 8, 1916 1,876,021 Quigley Sept. 6, 1932 1,985,531 Swenson Dec. 25, 1934 2,328,433 Dyer Aug. 31, 1943 2,398,564 Stoner Apr. 16, 1946 2,714,304 Dedda Aug. 2, 1955 2,848,798 Davis Aug. 26, 1958