US3792392A

US3792392A - Relay construction

Info

Publication number: US3792392A
Application number: US00316415A
Authority: US
Inventors: K Pohl
Original assignee: Bell Telephone Laboratories Inc
Current assignee: AT&T Corp
Priority date: 1972-12-18
Filing date: 1972-12-18
Publication date: 1974-02-12
Anticipated expiration: 1991-02-12

Abstract

The relay construction uses molded parts that are assembled without the use of fasteners. The relay comprises an electromagnet consisting of a core that is snap-mounted within a spool, the spool in turn being snap-mounted within an enclosure. An armature support, which includes an integral spring for biasing it to its unoperated position, is pivotally secured by snap-mounting to the enclosure and the armature itself is snapmounted to the support.

Description

' Feb. 12, 1974 United States Patent [1 1 Pub] FOREIGN PATENTS OR APPLICATIONS 1,199.628

I RELAY CONSTRUCTION [75] Inventor:

Karl-Heinz Pohl, Boulder, Colo.

Bell Telephone Laboratories,

[73] Assignee: 7/1970 Great Britain...................... 335/296 Incorporated, Murray Hill, Berkeley Primary ExaminerGeorge Harris n J Nm 8 M] gmw Ho m H M 2 1 Attorney, Agent, or Firm-H. L. Newman [57] ABSTRACT The relay construction uses molded parts that are as- 21 Appl. No.1 316,415

[52] S C sembled without the use of fasteners. The relay comprises an electromagnet consisting of a core that is 98 a 7M Q72 5 BMW 3 .m2 7 7 oo 2 l O y 2 3 1 6 3 9 1 0 7 n 00 5 1 Q U 3 3 [58] Field of Search snap-mounted within a spool, the spool in turn being 2 335/ 81 snap-mounted wlthin an enclosure. An armature sup- References Cited port, which includes an integral spring for biasing it to UNITED STATES PATENTS its unoperated position, 'is pivotally secured by snap- I mounting to the enclosure and the armature itself is snap-mounted to the support.

2,513,965 Pett t 335/296 X 2,527,220 Hughes........................r.. 335/279 X 2 804 519 8/1957 Slonneger....................... 335/187 X 10 Clairns, 2 Drawing Figures RELAY CONSTRUCTION FIELD OF THE INVENTION This invention relates to relay construction and within that field to relays'that are designed so that the components thereof are assembled without the use of fasteners.

BACKGROUND OF THE INVENTION With the cost of labor becoming an ever-increasing factor in the cost of manufacturing electromagnetically operated switching systems, it has become increasingly desirable to reduce the time necessary to assemble the many components that comprise such switching systems. One area that has not received much attention heretofore is the relays that are used in great quantity in each system. At the present time the typical relay is assembled by the use of a variety of fasteners such as bolts, nuts, eyelets, rivets, and so forth. Thus the time required to secure the various components of the relay together is significant.

SUMMARY OF THE INVENTION A relay structure is herein disclosed that is assembled without the use of fasteners thereby effecting a substantial reduction in time required to assemble the relay. The relay comprises an electromagnet consisting of a core that is snap-mounted within a spool, the spool in turn being snap-mounted within an enclosure. An armature support, which includes an integral spring for biasing it to its unoperated position, is pivotally securedv DESCRIPTION OF THE DRAWING FIG. 1 is a partially exploded perspective view of a relay in accordance with this invention, portions being broken away for greater clarity; and

FIG. 2 is an exploded perspective view in section showing the electromagnet assembly and the portion of the enclosure in which it is accommodated.

DETAILED DESCRIPTION OF THE INVENTION Referring to the drawing, a relay in accordance with this invention comprises an enclosure 100, an electromagnet assembly 200, an armature assembly 300, and a switch assembly 400. As shown most clearly in FIG. 2, the electromagnetic assembly 200 includes a cylindricaliron core 210 having a flange 212 at the upper end thereof and a pair of spaced notches 214 situated beneath the flange. In addition the core 210 has a pair of tapered cavities 216 and 218 in the upper and lower ends thereof, the cavities being concentric with the longitudinal axis of the core.

The portion of the core 210 beneath the flange 212 is accommodated within a closely conforming bore 222 of a unitary non-magnetic spool 220. The upper end of the bore 222 includes a pair of opposed L-shaped cantilever latch fingers 224, each of which comprises an upstanding flexible'leg 225 and a holding leg 226 extending laterally toward the other latch finger. The free ends of the holding legs 226 are spaced closer together than the diameter of the bore, and the upper surface of each includes an inclined deflecting surface. In addition, the spool 220 has a circular recess 228 in the upper end thereof for accommodating the flange 212 of the core 210, and the distance between the bottom surface of the recess and the under surface of the holding legs 226 is slightly greater than the distance between the under surface of the flange and the bottom surface of the notches 214.

As a result of these relationships, when the core 210 is inserted into the bore 222 of the spool 220, the latch fingers 224 are deflected away from one another. However, as the undersurface of the flange 212 engages the bottom surface of the recess 228, the notches 214 are positioned in registration with the holding legs 226. The latch fingers 224 t-hen snap toward each other, moving the holding legs 226 into the notches 214 to secure the core 210 to the spool 220.

The spool 220 further includes a square upper end flange 230, a circular lower end flange 232, and a cylindrical hub 234 therebetween. The diameter of the lower end flange 232 is somewhat less than the length of the sides of the upper end flange 230, and the perimeter of the lower end flange is relieved to provide a circumferential lip 236. A coil 250 is wound about the hub 234, and the axial cavities 216 and 218 in the ends of the core 210 permit the core to be used as a spindle during the winding operation. Each end of the coil 250 is joined to an individual terminal 252 (only one of which is shown), that is mounted in the lower end flange 232.

The electromagnet assembly 200 thereby formed is received within a rectangular chamber in the enclosure 100, the chamber comprising an opening 112, a relieved shoulder 114 circumscribing the upper end of the opening, and two pairs of diametrically opposed spring fingers 116 depending from the lower end of the opening. The opening 112 is of a size to accommodate the lower end flange 232 but not the upper end flange 230, the upper end flange being accommodated by the shoulder 114. In addition, the inside surfaces of the spring fingers 116 taper toward one another such that the distance between the lower ends of opposed fingers is less than the diameter of the lower end flange 232. Furthermore, the distance between the bottom surface of the shoulder 114 and the lower ends of the spring fingers 116 is slightly less than the distance between the underside of the upper end flange 230 and the upper surface of the lip 236.

Consequently, when the electromagnet assembly 200 is inserted into the chamber 110, the spring fingers 116 are deflected away from one another by the lower end flange 232. Then as the undersurface of the upper end flange moves into engagement with the bottom surface of the shoulder 114, the, lip 236 moves beneath the spring fingers 116 permitting them to snap toward each other and secure the electromagnetic assembly 200 within the chamber 110.

To facilitate automated insertion of the electromagnet assembly 200 into the-chamber l 10 and automated electrical connection to the coil 250 subsequent to insertion, the upper end of the spool 220 has a pair of concentric

circular grooves

238 and 240 formed therein. The grooves 238 and- 240 each have an individual stop (not shown) that interrupts the continuity thereof and the two stops are diametrically opposed to one another. By again using the core 210 as a spindle and by respectively inserting a pair of diametrically opposed pins into the

grooves

238 and 240 and rotating the pins about the longitudinal axis of the core into engagement with the stops and thereafter using the pins to rotate the electromagnet assembly 200 to a predetermined position, the electromagnet assembly is automatically located so that when it is inserted into the chamber 110 the upper end flange 230 is properly oriented with respect to the shoulder 114 and the terminals 252 have a known orientation with respect to the enclosure 100.

Referring now to FIG. 1, the armature assembly 300 of the relay includes an armature 310 accommodated by a nonmagnetic armature support 320 extending radially from a rotatable shaft 330 into juxtaposition with the electromagnet assembly 200. The armature 310 comprises a disk-shaped member having a coaxial cylindrical boss 312 extending from each side thereof, and the bosses are of equal size. The armature support 320 comprises a cylindrical cup-shaped member having a base 322 circumscribed by a peripheral wall 324, the inside surface of the wall being slightly larger in diameter than the armature 310. The base 322 has a circular opening 325 in the center thereof of a size to accommodate the bosses 312 of the armature 310 while the peripheral wall 325 has a plurality of integral cantilever latch fingers 326 spaced thereabout. Each latch finger 326 is an inverted L-shaped element comprising a flexible leg 327 extending upwardly from the base 322 and a holding leg 328 extending radially inward parallel to the base. The free end of each holding leg 328 extends inside the peripheral wall 324, and the upper surface thereof has an inclined deflecting surface. In addition, the under surface of each holding leg 328. is spaced from the upper surface from the base a slightly greater distance than the height of the armature 310 at its perimeter.

With these relationships the armature 310 is mounted in the armature support 320 by merely orienting it in a plane parallel thereto in registration with the peripheral wall 324 and pressing it toward the base 322. The engagement of the armature 310 with the deflecting surfaces of the holding legs 328 deflects the latch fingers 326 outwardly. Then when the armature 310 moves into engagement with the upper surface of the base 322, the latch fingers snap inwardly, moving the holding legs over the perimeter of the armature and securing the armature within the armature support 320.

Inasmuch as the armature 310 is completely symmetrical, the armature lends itself to automation. In addition, the relay can be made either latching or nonlatching depending upon the height of the bosses 312 with respect to the thickness of the base 322. If the relay is non-latching, the height of the bosses 312 is slightly less than the thickness of the base 322, whereas if the relay is latching, the height of the bosses exceeds the thickness of the base. Finally, the dimensions of the armature 310 and armature support 320 are selected so that the armature is free-floating within the support. As a result, even though the armature 310 moves through an arcuate path, it is able to orient itself parallel to the top surface of the core 210 (FIG. 2) to achieve the greatest magnetic attraction. in the case of the latching embodiment, this means that the armature 310 makes full face contact with the core 210, reducing the residual magnetism needed to hold the armature in the latched position.

The shaft 330 from which the armature support 320 extends is journaled in a pair of U-shaped bearings upstanding from the enclosure 100, the shaft having a pair of spaced flanges 332 the remote surfaces of which are spaced approximately the same distance apart as. the facing surfaces of the bearings. A cantilever latch a holding leg 134 extending laterally toward the other latch finger. The free end of the holding legs 134 are spaced closer together than the length of the shaft 330 and the upper surface of each includes an inclined deflecting surface. The underside of each holding leg 134 is spaced from the bottom of the adjacent U-shaped opening in the bearing 120 approximately the same distance as the diameter of the associated end of the shaft Consequently, the shaft 330 is mounted in the bearings 120 by locating it over the U-shaped openings in the bearings with the flanges 332 situated on the inside of the bearings and then pressing it downward. The latch fingers are deflected away from one another until the ends of the shaft engage the bottom surfaces of the bearings 120. The latch fingers 130 thereupon snap toward each other and the holding legs 134 move over the ends of the shaft 330 to secure the shaft within the bearings 120. The interaction between the flanges 332 and the bearings 120 prevents axial displacement of the shaft 330. i

The shaft 330 further includes an integral-flexible tapered vane 334 extending radially therefrom. The vane 334 is positioned within an opening in the enclosure 100 that includes a pair of opposed rounded protrusions 142., The adjacent surfaces of the protrusions are spaced approximately the same distance apart as the thickness of the portion of the vane 334 positioned therebetween. Thus, when the-relay is energized and the armature 310 is drawn toward the core 210, the shaft 330 is rotated and the vane 334 is flexed. Then upon de-energization of the relay, the vane returns the armature 310 to its unoperated position.

Finally, the shaft 330 includes a pair of integral actuating fingers 336 that extend adjacent to the switch assembly 400. A switch assembly particularly adapted for use in the relay is disclosed in my copending application Ser. No. 303,497 filed Nov. 3, 1972 and assigned to the same assignee as the present invention. Suffice it to say that the switch assembly includes a pair of contact pileups 410 about which rectangular actuators 420 are disposed. when the relay is energized, the rotation of the shaft 330 moves the actuating fingers 336 into engagement with actuators 420 to operate the contact pileups 410. When upon de-energization of the relay the actuating fingers 336 are moved away from the actuators 420, the contact springs of the pileups 410 return the switches to their unoperated position.

Although but one embodiment has been disclosed and described, it will be understood that it is but illustrative and that various modifications may be made therein without departing from the scope and spirit of this invention as defined in the appended claims. Furthermore it is to be understood that the relay of this invention is not limited to any particular orientation, and terms such as upper, beneath and so forth appearing in the claims are only employed to establish relative positions between the elements of the relay.

What is claimed is:

l. A relay comprising:

an electromagnet including a core and a coil disposed about the core;

a non-magnetic armature support pivotally mounted adjacent to the electromagnet, the armature support including a base having an opening therein;

an armature accommodated by the armature support, the armature including a boss that extends into the opening in the base of the armature support and being located by the armature support in juxtaposition with the core of the electromagnet,

2. A relay as in claim 1 wherein the armature support includes a peripheral wall upstanding from the base and the peripheral wall has a plurality of integral cantilever latch fingers spaced thereabout for securing the armature to the armature support.

3. A relay as in claim 2 wherein the armature is a disk-shaped element generally conforming to the configuration of the peripheral wall and each latch finger is an inverted L-shaped element comprising an upstanding flexible leg and a laterally extending holding leg, the holding leg of each latch finger being spaced from the base approximately the same distance as the height of theportion of the armature engaged thereby.

4. A relay as in claim 1 wherein the opening in the base is circular and is located in the center of the base and the armature is a disk-shaped member that is symmetrical about its longitudinal axis and has a cylindrical boss extending from both sides thereof.

5. A relay as in claim 1 wherein the core of the electromagnet has a flange and a plurality of notches located beneath the flange, and the coil is-wound about a spool that has a central bore of a size to accommodate the portion of the core beneath the flange but not the flange itself, the spool further having a plurality of cantilever latch fingers, the latch fingers engaging the notches in the core when the core flange is positioned in engagement with the end of the spool to secure the core to the spool.

6. A relay as in claim 5 wherein the spool includes upper and lower end flanges, the upper end flange being larger than the lower end flange and the perimeter of the lower end flange is relieved to provide a leg, and an enclosure having an opening therein for receiving the electromagnet, the opening being smaller than the upper end flange and larger than the lower end flange and the lower end of the opening having opposed flexible fingers depending therefrom, the distance between the inside surface of the opposed flexible fingers at the lower ends thereof being smaller than the lower end flange, and the fingers being of a length that when the upper end flange is in engagement with the upper end of the enclosure the fingers are in engagement with the lip in the lower end flange.

7. A relay as in claim 5 wherein the core has a tapered axial cavity in each end thereof, permitting it to serve as a spindle during the winding of the coil on the spool.

8. A relay as in claim 1 wherein the electromagnet is accommodated by an enclosure and the armature support extends radially from a rotatable shaft, the enclosure having a pair of spaced bearings having U-shaped openings therein for rotatably supporting the ends of the shaft and the enclosure further having a cantilever latch finger adjacent .to each bearing for holding the shaft in the bearing, each latch finger comprising an inverted L-shaped element having an upstanding flexible leg and a laterally extending holding leg, the holding leg of each latch finger being spaced from the bottom of the adjacent U-shaped opening approximately the same distance as the diameter of the associated end of the shaft.

9. A relay as in claim 8 wherein the shaft includes an integral flexible vane extending generally radially therefrom and the enclosure includes an opening for accommodating the end of the vane, the sides of the opening being spaced apart approximately the same distance as the thickness of the vane, the vane serving as a return spring for the relay.

10. A relay as in claim 8 wherein the shaft includes fingers for actuating switches mounted adjacent to the shaft.

Claims

1. A relay comprising: an electromagnet including a core and a coil disposed about the core; a non-magnetic armature support pivotally mounted adjacent to the electromagnet, the armature support including a base having an opening therein; an armature accommodated by the armature support, the armature including a boss that extends into the opening in the base of the armature support and being located by the armature support in juxtaposition with the core of the electromagnet.

3. A relay as in claim 2 wherein the armature is a disk-shaped element generally conforming to the configuration of the peripheral wall and each latch finger is an inverted L-shaped element comprising an upstanding flexible leg and a laterally extending holding leg, the holding leg of each latch finger being spaced from the base approximately the same distance as the height of the portion of the armature engaged thereby.

5. A relay as in claim 1 wherein the core of the electromagnet has a flange and a plurality of notches located beneath the flange, and the coil is wound about a spool that has a central bore of a size to accommodate the portion of the core beneath the flange but not the flange itself, the spool further having a plurality of cantilever latch fingers, the latch fingers engaging the notches in the core when the core flange is positioned in engagement with the end of the spool to secure the core to the spool.

8. A relay as in claim 1 wherein the electromagnet is accommodated by an enclosure and the armature support extends radially from a rotatable shaft, the enclosure having a pair of spaced bearings having U-shaped openings therein for rotatably supporting the ends of the shaft and the enclosure further having a cantilever latch finger adjacent to each bearing for holding the shaft in the bearing, each latch finger comprising an inverted L-shaped element having an upstanding flexible leg and a laterally extending holding leg, the holding leg of each latch finger being spaced from the bottom of the adjacent U-shaped opening approximately the same distance as the diameter of the associated end of the shaft.