US3889216A

US3889216A - Electromagnetic relay assembly

Info

Publication number: US3889216A
Application number: US306114A
Authority: US
Inventors: Kemper Martel Hammell
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1972-11-13
Filing date: 1972-11-13
Publication date: 1975-06-10
Anticipated expiration: 1992-06-10

Abstract

A package containing one or more electromagnet relays and more particularly it relates to the switches, contacts and posts therein which are stamped and completely formed from a single flat sheet of material.

Description

PATENTEDJUN 10 I915 SHEET ELECTROMAGNETIC RELAY ASSEMBLY BACKGROUND OF THE INVENTION Electromagnetic relays have been known and used for many years in a variety of ways. In more recent years the demands of modern technology have required unusually high degrees of performance under extreme environmental conditions; e.g., space exploration, and further have required along with such performance, miniaturization.

Of the several components within currently popular electromagnetic relays, the contact systems and switches are quite complex, and contain a relatively large number of diverse parts wherein the mechanical connections thereinbetween are subject to failure from rough handling and usage.

Accordingly, a primary object of the invention is to construct a package containing an electromagnetic relay assembly which reduces the complexity and number of parts thereof to an absolute minimum.

Another object of the invention is to construct electric contacts and switches used in an electromagnetic relay from a single strip of metal solely by stamping and forming operations.

Other objects and advantages of the invention will become apparent from the following detailed description taken in connection with the accompanying drawmgs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective view of a completed package embodying novel features of the present invention;

FIG. 2 is a perspective view of the assembly within the package of FIG. 1 before final forming of the frame and the placement of the housing;

FIG. 3 shows the frame after the stamping operation;

FIG. 4 is an enlarged view of a portion of the frame of FIG. 3;

FIG. 5 shows the frame after forming the contacts and switches thereon;

FIG. 6 is an enlarged view of a portion of the frame of FIG. 5;

FIG. 7 is a top plan view of one half of the assembly showing details of the novel contacts and switching units;

FIG. 8 is a perspective view of the base of the housing for the assembly of FIG. 2;

FIG. 9 is a perspective view of the top half of the housing for the assembly of FIG. 2;

FIG. 10 shows one modification of the package of FIG. 1; and

FIG. 11 shows one modification of the frame of FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 discloses a completely assembled, ready for use electromagnetic relay package 10. Two rows 11 of posts or pins 12, one on either side of housing 14, extend outwardly therefrom and depend downwardly from the housing. The pins 12 are conventionally spaced and arranged so as to be readily received in receptacles in conventional printed circuit boards (not shown) and the like.

More specifically, housing 14 is composed of two halves, an inverted top half l6 and a base 18, which are cemented together at the final assembly point to form an environmentally sealed package.

The components within base 18 of housing 14, as seen in FIG. 2, include two electromagnet assemblies 20 and a frame 22, which includes aforementioned pins 12. Frame 22 also includes, integrally therewith, electromagnet lead contacts 24 and switch assemblies 26.

The electromagnet assemblies 20 of the present invention comprise electromagnets 28, metal plate 30 and bell crank arms 32 which are the linkage connecting the electromagnets to the switch assemblies 26. Further, assemblies 20 include lead wires 34 coming from each electromagnet 28 and fixed as by soldering to lead contacts 24.

The development of frame 22 and the novel construction of switch assemblies 26 from suitable flat mill stock and without additional parts or pieces will now be disclosed with references being made to FIGS. 3, 4, 5, and 6.

A roll of mill stock (not shown) of a spring tempered conductive material such as phospher bronze or berillium copper, having suitable width and thickness dimensions, is plated with a suitable switch contact metal at the areas which will become contact points. The roll is fed into a fabricating die (not shown) to produce a continuous strip of repeating frames 22, one of which is shown in FIG. 3. This operation,referred to as a blanking operation, stamps out, for each frame 22, two opposing rows 11 of contact members which are generally designated at 36, whose inner ends define an elongated central opening 37.

Pins 12 are the outer end portions of contact members 36. In addition to the pins, contact members 36 include as an integral part thereof an intermediate portion 38 and various shaped inner end portions or arms which are for the moment collectively designated at 4th. The arms or inner end portions define the aforementioned central opening 37 whose longitudinal axis parallels rows 11.

Contact members 36 are connected to each other and to end strips 44 of frame 22 by web portions 46.

Each row 11 contains two sets of four contact members 36, each set being a mirror image of the other set in that row. Thus, as FIG. 3 shows, one frame 22 contains four sets of four contact members each. FIG. 4 shows one such set which has been enlarged for the purpose of more easily describing the set and more particularly each of the inner end portions 40.

The inner end portion of the contact member 36 adjacent the segment of end strip 44 shown is hereinafter designated as a first fixed arm 48. Arm 48 contains a notch 50 opening away from the end strip 44; i.e., toward the second set in the row 11. The notch defines an inwardly extending projection on the end of arm 48 which has the aforementioned preplated contact point on its upper surface and which constitutes the normally closed" contact 52.

The inner end portion 40 positioned to the immediate right of the first fixed arm 48 is hereinafter designated as the second fixed arm 54. As seen in FIG. 4, the arm extends normal to the axis of member 36 and toward the first fixed arm 48. The tip of arm 54, which is narrower than the rest, protrudes into notch 50 with its preplated contact point (seen in phantom) on the side facing downwardly away from the reader. The tip constitutes the normally opened contact 56.

Inner end portion 40 of the contact member 36 immediately to the right of the second fixed arm 54 is the electromagnet lead contact 24 herembefore mentioned as being the contact which receives thereon one of the two leads 34 originating from one of the two electromagnets 28 (see FIG. 2).

Inner end portion 40 of the contact member 36 to the far right in FIG. 4 has been stamped out to form a arm 58. The greater portion of arm 58 extends parallel to row 11. The free end of arm 58, plated on both sides to form double contact 60, terminates within notch 50 immediately adjacent to contact 56 of the second fixed arm 54.

The portion of arm 58 which is parallel to row 11 and the double contact 60 constitutes common switching blade 62. The blade has been swaged or thinned at a section adjacent the fixed end and generally designated at 63. The swagging enhances the flexibility of the blade as well as increases its length whereby contact 60 is projected deeper into notch 50. A section of blade 62 is notched to form a shoulder 64 and a step 66. The section of inner end portion 40 between arm 58 and intermediate portion 38 is referred to as the hinge post and is generally designated at 68.

Subsequent to the blanking operation which stamped out frames 22 as shown in FIGS. 3 and 4, the .roll is fed through a second stage of the fabricating die (not shown) wherein the frames are formed. The forming operation bends the appropriate inner end portions 40 in an appropriate manner to make switch assemblies 26.

FIG. 5 illustrates one complete frame 22 wherein the forming operation has constructed four switch assemblies 26, one assembly from each of the four sets of contact members 36 hereinabove mentioned. Each row 11 contains two such assemblies in tandem relation.

Again, one set of four contact members constituting a switch assembly 26, has been lifted out of a frame 22 and enlarged for ease in seeing the novel structure. This enlargement, seen in FIG. 6 to which reference will now be made, is of the same set of four members 36 as was shown in FIG. 4.

From a studyof FIG. 6 it is seen that

arms

48, 54, and 58 have been turned upwardly and by so turning each arm at a predetermined location thereon, assembly 26 is formed and without additional work thereto. The two fixed

arms

48 and 54 are spaced apart from each other with free end 60 of switch blade 62 thereinbetween.

Both

arms

48 and 54 are fixed relatively immobile. As noted above, switching blade 62 is movable. This mobility is derived from the relatively short thin spring hinge post 68.

The switching of switching blade 62 by the energizing of electromagnet 28 will now be described with particular reference to FIG. 7 which is a view looking down upon one-half of an assembled package 10 sans the top half 16 of housing 14.

Electromagnet assembly 20 includes plate which has a retention boss 70 projecting therefrom at about the midpoint (not shown) of the armature. As shown in FIG. 7, boss 70 is T-shaped in a horizontal cross-section where the spaces on either side of the stem and between the cap of the T and the main body of plate 30 provide pockets which loosely receives the inwardly projecting cars 72 of bell crank 36, such ears also providing the positioning and retaining means for the plate. Arms 32 extend outwardly from plate 30, a portion designated at 74 to a point slightly beyond the edge of the electromagnets 28 where they bend around and extend parallel thereto, a portion designated at 76. The underside (not shown) of the portion of each arm 32 which is parallel to electromagnet 28 is grooved to receive the step 66 portion of switch blade 62. It is in this fashion that plate 30 and bell crank arms 32 are held in place by switch blade 62.

Upon assembly, blades 62 are spring biased against normally closed contacts 52 by slightly twisting hinge post 68. Whenever electromagnet 28 is energized, plate 30 is moved into engagement with the core portion thereof in the conventional manner. This movement, which is in the direction of arrow 78 in FIG. 7 pushes the portions 74 of arms 62 toward electromagnet 28. The parallel portions 76 of the arms tries to move in the same direction as portions 74 but are restrained by shoulders 64 and the rigidity of arm 58 in that plane. This restraint forces arms 32 and of course blades 62 to move outwardly from the swaged area 63; i.e., in the direction of arrow 80 seen in the vicinity of contacts 52 56, so that the double contact 60 abutts against normally opened contact 56 making electrical contact therewith. Upon electromagnet 28 being de-energized, the force attracting plate 30 disappears and it, along with bell crank arms 62, are returned to the position seen in FIG. 7 by the return of switch blades 62 to their spring biased position abutting normally closed contact 52.

As is well understood by those familar with the art, energizing of electromagnets 28 is accomplished via leads 34 and lead contacts 24.

FIG. 8 illustrates the base 18 of housing 14. The base includes a center divider 82 which in turn includes T- members 83. The T-members center electromagnets 28 in the base while longitudinal grooves 84, one on each side of divider 82, receive a portion of electromagnet 28 therein; i.e., an outer leg of the core. The major portion of electromagnet 28 rests in base surface 86. Sixteen slots 88 are provided on side walls 90 through which contact members 36 pass and on which intermediate portions 38 thereof rest. End walls 91 complete the description of base 18.

FIG. 9 illustrates the inside of the top half 16 of housing 14. The top half includes a center divider 92 and T- members 94 thereto which serve to center electromagnets 28 into recesses 96. Side, top and end walls, 98, 99 and 100 respectively, complete the description of top half 16.

Having described the forming of switch assemblies 26 and housing 14, the assembly of the several components into package 10 will now be discussed.

Following the forming of frame 22 into the structure disclosed in FIGS. 5 and 6, and the application of a bonding film to each of the slots 88 of the base, the frame, complete with bell cranks and plates, is placed into base 18 with end strips 44 on the outside of end walls 91 and pins 12 of contact members 36 projecting out through slots 88 on side walls 90. Reference to FIG. 2 will show this positioning; note that intermediate portions 38 of members 36 rest on top of the side walls in slots 88 while web portions 46 and pins 12 project beyond.

The bonding film is then cured providing an integral mechanical union between base 18 and members 36. Thereafter web portions 46 and end strips 44 are removed. After bonding material is applied to cross members 83, electromagnets 28 are positioned through central opening 37 of frame 22 and into base 18. Lead wires 34 are affixed to lead contacts 24 and switch blades 62 are adjusted to properly bias against normally closed contact 52. Next, each electromagnet is brought sufficiently close to its plate 30 to obtain adequate switching action at minimum voltage. The bonding between the electromagnets and members 88 is then cured. Thereafter the partially completed assembly is completely tested before final encapsulation. After testing, top half 16 is placed onto the assembly and bonded thereto to form the environmentally sealed package. The final step is to place the assembly in a final die (not shown) which bends posts or pins 12 downwardly (relative to top half 16 of housing 14).

FIG. illustrates a modified embodiment 110 of package 10, the difference being the inclusion of an aluminum heat sink 112 incorporated into top half 16 in lieu of the top wall 99 and which is thermally bonded to each electromagnet. The heat sink acts to maintain the efficiency of the package by maintaining a relative small temperature rise in the coils of the electromagnets.

FIG. 11 illustrates a modified frame 122 which incorporates a single switch assembly 26 for use in a package 10 requiring only one such switch. As is obvious to those skilled in the art, any number of such modifications can be made.

Another modification which is adapted to the invention disclosed herein is to evacuate the interior of package 10 after bonding the two housing halves together and back fill it with a suitable inert gas. This modification would only require a scalable hole in base 18, preferably in the vicinity of center divider 82.

Housing 14 may be made from a number of electrically insulating materials such as a plastic for conventional environmental use or a ceramic for use where hermetic encapsulation is desirable.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, as some modifications will be obvious to those skilled in the art.

What is claimed is:

1. An electrically-driven mechanical device for switching an electrical current from one circuit to another, which comprises:

a. an insulating housing;

b. switching assemblies stamped from a single coplanar sheet of conductor material and formed to provide:

i. a plurality of posts spaced apart and formed into two parallel rows, each row depending downwardly from a side of the housing and adapted for insertion into a printed citcuit board receptacles for engagement with electrical circuits thereon,

ii. a pair of adjacent contact members each being an integral continuation of one of adjacent posts and projecting into said housing, the first member having a portion defining a first fixed Contact and the second member having a lateral projection overlapping and spaced from the first fixed contact and defining a second fixed contact,

iii. a third contact member being an integral continuation of one of said posts positioned in the same row as the aforementioned pair of adjacent posts and projecting into the housing, said member having an elongated, laterally flexible arm with the free end thereof extending in between the first and second fixed contacts; and

c. electro-magnetic means for moving the flexible arm on the third contact member into electrical contact with either the first or second fixed contacts thereby switching an electrical current which may flow thru the third contact member from one to the other fixed contact member.

2. The device of claim 1 wherein the elongated, laterally flexible arm has been swaged to define a hinged area of reduced material stress thereby increasing the flexibility of the arm.

3. An electromagnetic relay assembly which comprises:

a. a housing of insulating material;

b. a plurality of switching means all stamped from a single coplanar sheet of conductive material and formed to provide spaced sets of contact members, each set including:

i. a first contact member having at one end a post depending downwardly from said housing, and adapted for insertion into an electrical circuitconnected receptacle and at another end and positioned within the housing, a vertical projection defining a first fixed contact,

ii. a second contact member, adjacent to the first, having at one end a post depending downwardly from said housing and adapted for insertion into an electrical circuit-connected receptacle, and at another end and positioned within the housing, a lateral projection defining a second fixed contact disposed in an overlapping, spaced apart relation to the first fixed contact so that the two fixed contacts define in cooperation with each other a slot thereinbetween,

iii. a third contact member, adjacent to the second, having at one end a post depending downwardly from said housing and adapted for insertion into an electrical circuit-connected receptacle and at another end and positioned within the housing, a projection adapted to receive an electrical lead from an electromagnet, and

iv. a fourth contact member, adjacent to the third, having at one end a post depending downwardly from said housing and adapted for insertion into an electrical circuit-connected receptacle and at another end and positioned within the housing, an elongated arm with its free end extending into the slot between the first and second fixed contacts and engageable with either contact, said arm being movable laterally;

c. an electromagnet positioned between each of two sets of contact members within the housing and having electrical leads therefrom attached to the third contact member of each set whereby the electromagnet may be electrically energized; and

d. connecting means connecting the electromagnet to the elongated arm of each set so that each time the electromagnet is energized, the elongated arms are moved laterally and the free ends thereof are shifted from one fixed contact to another and an electric current which may be flowing thru the fourth contact member and one fixed contact member is shifted to the other fixed contact member.

4. The electromagnetic relay assembly of claim 3 wherein the elongated arm on the fourth contact member has been swaged to extrude the free end further in between the two fixed contacts and also to define a hinge area of reduced material stress.

Claims

1. An electrically-driven mechanical device for switching an electrical curRent from one circuit to another, which comprises: a. an insulating housing; b. switching assemblies stamped from a single coplanar sheet of conductor material and formed to provide: i. a plurality of posts spaced apart and formed into two parallel rows, each row depending downwardly from a side of the housing and adapted for insertion into a printed citcuit board receptacles for engagement with electrical circuits thereon, ii. a pair of adjacent contact members each being an integral continuation of one of adjacent posts and projecting into said housing, the first member having a portion defining a first fixed contact and the second member having a lateral projection overlapping and spaced from the first fixed contact and defining a second fixed contact, iii. a third contact member being an integral continuation of one of said posts positioned in the same row as the aforementioned pair of adjacent posts and projecting into the housing, said member having an elongated, laterally flexible arm with the free end thereof extending in between the first and second fixed contacts; and c. electro-magnetic means for moving the flexible arm on the third contact member into electrical contact with either the first or second fixed contacts thereby switching an electrical current which may flow thru the third contact member from one to the other fixed contact member.

3. An electromagnetic relay assembly which comprises: a. a housing of insulating material; b. a plurality of switching means all stamped from a single coplanar sheet of conductive material and formed to provide spaced sets of contact members, each set including: i. a first contact member having at one end a post depending downwardly from said housing, and adapted for insertion into an electrical circuit-connected receptacle and at another end and positioned within the housing, a vertical projection defining a first fixed contact, ii. a second contact member, adjacent to the first, having at one end a post depending downwardly from said housing and adapted for insertion into an electrical circuit-connected receptacle, and at another end and positioned within the housing, a lateral projection defining a second fixed contact disposed in an overlapping, spaced apart relation to the first fixed contact so that the two fixed contacts define in cooperation with each other a slot thereinbetween, iii. a third contact member, adjacent to the second, having at one end a post depending downwardly from said housing and adapted for insertion into an electrical circuit-connected receptacle and at another end and positioned within the housing, a projection adapted to receive an electrical lead from an electromagnet, and iv. a fourth contact member, adjacent to the third, having at one end a post depending downwardly from said housing and adapted for insertion into an electrical circuit-connected receptacle and at another end and positioned within the housing, an elongated arm with its free end extending into the slot between the first and second fixed contacts and engageable with either contact, said arm being movable laterally; c. an electromagnet positioned between each of two sets of contact members within the housing and having electrical leads therefrom attached to the third contact member of each set whereby the electromagnet may be electrically energized; and d. connecting means connecting the electromagnet to the elongated arm of each set so that each time the electromagnet is energized, the elongated arms are moved laterally and the free ends thereof are shifted from one fixed contact to another and an electric current which may be flowing thru the fourth contact member and one fixed contact member is shifted to the other fixed contact member.