US3168627A

US3168627A - Relay with positively driven contacts

Info

Publication number: US3168627A
Application number: US178001A
Authority: US
Inventors: James H Gilley
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1962-03-07
Filing date: 1962-03-07
Publication date: 1965-02-02
Anticipated expiration: 1982-02-02

Description

iFb. 2, 1965 J. H. GILLEY 3,168,627

RELAY WITH POSITIVELY DRIVEN CONTACTS Filed March 7, 1962 Z0 INVENTOR BY AQ/QW ATTORNEY United States Patent Ofiice Filed Mar. 7, 1962, Ser. No. 178,001 1 Claim. c1. zoo-s7 This invention relates to a relay with positively driven contacts and more particularly to a relay having facilities to provide rapid and positive operation of contacts.

Inthe operation of conventional relays, contacts often are before engagement and firequently rebound and chatter after engagement, These conditions are detrimental to satisfactory circuit operation; thereby resulting in poor connection between circuits.

Arcing accelerates the consumption of relay contacts by pitting and burning of thecontact surfaces; hence, maintenance problems aremultiplied and frequent replacement of relays is necessitated.

' Rebounding and chattering of contacts introduce harmonic frequencies which distort a signal desired to be transmitted through the contacts. For example, in a telephone switching circuit, these harmonic frequencies attenuate or mutilate the transmission of signals which are representative of intelligence.

An object of this invention is to provide a new and improved relay with positively driven contacts which is reliable in operation and simple of construction.

Another object is to provide a relay wherein the problems of arcing, rebounding, and chattering of contacts are alleviated.

Another object is to provide a snap-action relay wherein spring contact members are flexed and positively urged together.

An additional object is to provide a relay having facilities for camming contacts into positive engagement.

A still further object is to provide a snap-action relay wherein initially flexed spring contact arms are snapped together in response to the energization of a relay coil which moves a pair of cammed surfaces into engagement with the spring contact arms to abet the snap action and preclude rebounding.

With these and other objects in mind, the instant invention contemplates a relay having an armature which has a tapered sheet of insulation material on the end thereof. The tapered sheet is positioned between the ends of a pair of spring contact arms initially flexed toward each other. The armature has a plate attached thereto with inclined, diametrically opposed, cam slots through which the contact arms pass. Upon energization of the relay, the armature Withdraws the sheet from between the contact arms and drives the plate to apply a continuously, increasing force on the contact arms. This action forces the ends of the contact arms into engagement with the tapered sheet to effect a smooth transition from open-toclosed contact arms positions without rebounding and to maintain the contact arms in the closed position.

Other objects and advantages of the invention will become apparent by reference to the following detailed specification and drawings wherein:

FIG. 1 is a side view of a deenergized snap-action relay embodying the principles of the present invention;

'FIG. 2 is a side view of the snap-action relay in an energized condition particularly showing the flexing action of a cam plate on a pair of spring contact arms;

FIG. 3 is a perspective view of the relay, particularly illustrating the construction of the cam plate; and

FIG. 4 is a side view of another embodiment of a snapaction relay, incorporating the principles of the invention.

Referring to FIG. 1, there is shown a snap-action relay in a normally deenergized condition having a housing 9 3,168,627 Patented Feb. 2, 1965 containing a conventional relay coil 11 connected to a source of electrical energy 10. An, armature 12 passes through the housing 9 and has a collar 13 affixed thereto. The armature 12 is urged toward the left by the action of a spring 14 bearing against the collar 13 and the housing 9. Attached to theend of .the armature 12 is a sheet or plate of dielectric insulation material 16, such as mica, fiber, etc. The sheet is normally inserted between a pair of relay contact elements 17 attached to a pair of initially flexed spring contact arms18. These contact arms 18 are constructed of a spring-like metal and are oppositely bent to extend or incline toward each other. The spring contact arms 18 are mounted on threaded terminals'19 to which connections to electrical circuits (not shown) can be made. Nuts 20 are threaded on terminals 19 to mount the contact arms so that the arms engage the sheet 16 and are slightly flexed.

When the dielectric sheet 16 is removed from between the contact arms 18, the contact elements 17 are urged together by the spring action of th'econtact arms' 18 to complete "an electrical circuit through the contact elements and the contact arms. Also connected to the armature 17 is a plate 21 having oppositely inclined cam slots 22 formed therein through which the spring contact arms 18 pass.

In operation, the coil 11 is energized by the closure of a switch 31 which connects the source of electric energy,

10 and causes the armature 12 to be withdrawn into the coil, whereupon the dielectric sheet of insulation 16 is removed from between the contact elements 17. The spring contact arms 18 are forced together due to their spring-like construction to instantly snap the contact elements 17 together to complete an electrical circuit. As the armature 12 is further withdrawn into the coil 11, the plate 21, being alfixed to the armature, moves to the right (FIGS. 2 and 3) and acts upon the spring contact arms 18 to forcibly flex them together. Hence, a positive snap action of the relay contact elements 17 is assured. This flexing action by the plate 21 on the contact arms 18 holds the contact elements 17 in engagement with each other and precludes rebounding. Inasmuch as the contact elements 17 are instantly snapped together, there is little opportunity for arcing before the contacts meet.

In FIG. 4, there is shown another embodiment of a relay utilizing the principles of the invention. Elements of this relay having corresponding elements to those of [the relay shown in FIGS. 1, 2, and 3 have been designated with the same reference numbers. There is shown in FIG. 4 a relay having a housing 9 containing a relay coil 11 connected through a switch 31 to a source of electrical energy 10. An armature 12 has a U-shaped bracket 27 aflixed thereto. The bracket 27 has oppositely inclined cam slots 28 through which inclined spring contact arms 26 pass. The bracket 27 is held against a shoulder formed on the armature 12 by a spring 14 which is restrained at its opposite end by a collar 13. Attached to the end of the collar 13 is a sheet of dielectric material 16 which is positioned between the contact arms 26. The contact arms 26 are mounted on threaded terminals 19 affixed to the housing 9. Nuts 20 are threaded on terminals 19 to hold the contact arm 26 spaced from the dielectric sheet 16.

In operation, the switch 31 is closed and coil 11 is energized by electrical energy source 10 to withdraw the armature 12 into the coil 11. This action withdraws the dielectric insulating sheet 16 from between the contact arms 26 and also moves the U-shaped bracket 27 to act upon the contact arms 26 to urge them into engagement with each other. The spring contact arms 26 are urged apart by their own resiliency when the coil 11 is deenergized.

ture for engaging and applying a continuously progressive force on the contact arms,

a sheet of insulation material having one end thereof centrally aflixed to the plate and the armature, and

It is to be understood that the above embodiments are merely illustrative of the principles of this invention, and numerous other arrangements could be devised without departing from the invention; p

rendered effective by the movement of said arma- What is claimed is: 5 having the other end thereof sharply tapered to a A relay comprising, 1 point, and positioned between said contact elements a housing; t for precluding said contact elements from snapping a coil mounted on said housing, into contact'with each other, and V i an armature having 'a collar secured thereto T- and means for energizing said coil to move the armature mounted to be moved within said coil, i 1 to withdraw the tapered end portion of 'said sheet a spring acting between said collar and housing-for 1 from between said contact elements and for driving biasing said armature out of said coil, the plate to apply the continuously progressive force 1 a pair of terminals afiixed to said housing in spaced on the contact arms during withdrawal to force the opposition to each other, contact elements into engagement with the tapereda pair of initially fiexed spring contact arms having 15 end P and aftertwithdrawal totpositivfily hold end mounted on Said terminals and a r said contact elements in their contacted position.

' g g gg g flee i Opposltely mchned g f f References Cited in the file of this patent" a pair of contactelements attached to the free ends UNITED STATES PATENTS r 0f ai c n ct r v 20 1,214,771 Fortier Feb. 6, 1 917 a plate connected to'jthe armature having inclined 1,629,640 Schachtner May 24, 1927 di'ametricallyi opposed cam slots formed therein 2,558,188 VMcWilliams June 26, 1951 through which said spring contact arms pass and 2,917,601 Hatchett 1.

3,017,476 7' "Becka Jan. 16, 1962