US3575678A

US3575678A - Reed switch assembly

Info

Publication number: US3575678A
Application number: US863958A
Authority: US
Inventors: William Forbes Barton
Original assignee: GRIGSBY BARTON Inc
Current assignee: GRIGSBY BARTON Inc
Priority date: 1969-10-06
Filing date: 1969-10-06
Publication date: 1971-04-20
Anticipated expiration: 1988-04-20
Also published as: GB1266817A; DE2049093A1; JPS4922617B1; BE757101A; DE2049093B2; FR2065033A5

Abstract

A relay assembly having a reed switch and an encircling coil encapsulated in an insulating body which also encloses a portion of a flat frame having a plurality of elongated contact members with inner end portions connected to terminals of the coil and switch within the body and outer end portions spaced apart in rows in parallel planes for insertion in printed circuit boards, the frame being formed from a blank having parts which cooperate with a mold to form the body.

Description

United States Patent- 3,ll4,807 12/1963 Koda William Forbes Barton Arlington Heights, [11. 863,958

Oct. 6, 1 969 Apr. 20, 197 l Grigsby-Barton, lnc. Arlington Heights, Ill.

lnventor Appl. No. Filed Patented Assignee REED SWITCH ASSEMBLY 10 Claims, 4 Drawing Figs.

US. Cl .Q 335/151 Int.Cl ....H0lh 51/28 FieldofSearch 335/15]- -l54, 202; 3 l 7/101 (CC); 264/272; l74/52.6

References Cited UNITED STATES PATENTS 3,423,516 l/l969 Segerson 3,436,810 4/1969 Kauffman Primary Examiner-l-larold Broome Assistant Examiner-R. N. Envall, Jr. AttorneyAnderson, Luedeka, Fitch, Even and Tabin ABSTRACT: A relay assembly having a reed switch and an encircling coil encapsulated in an insulating body which also encloses a portion of a flat frame having a plurality of elongated contact members with inner end portions connected to terminals of the coil and switch within the body and outer end portions spaced apart in rows in parallel planes for insertion in printed circuit boards, the frame being formed from a blank having parts which cooperate with a mold to form the body.

PATENTEDAPRZOIHYI 3575.678

FIG. 2

A vnLuAu roams BA REED SWITCH ASSEMBLY This invention relates generally to a reed relay having a switch with reeds of magneticmaterial enclosed in a tube of insulating material and a coil encircling the tube to provide a magnetic field for actuating the switch in response to energization and deenergization of the coil. More particularly, the invention resides in an assembly including a reed relay and adapted, by virtue of the size and location of connectors, for use with printed circuit boards.

A primary object of the invention is to construct a reed relay assembly of the above character in a novel manner to achieve simplicity and low cost while facilitating adaptability to printed circuit boards having different characteristics such as spacing, shapes and sizes of connectors.

Another object is to assemble the parts of a reed relay in a novel manner with an easily formed and manipulated connector frame adaptable readily to different sizes, shapes and spacings of connectors and cooperating with a mold to confine the flow of molding material for an enclosing housing.

Other objects and advantages of the invention will become apparent from the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of a completed reed relay assembly embodying novel features of the present invention with some of the parts of the housing broken away.

FIG. 2 is a plan view of a blank for the connector frame of the assembly with some parts connected to the blank, the housing and subsequently removed parts of the blank being shown in phantom. I

FIGS. 3 and 4 are end and side elevational views respectively of the parts shown in FIG. 2. 1

The reed relay assembly illustrated in the drawings is especially adapted for use with printed circuit boards and for interchangeability with other parts intended for such use. Printed circuit boards in current use are formed with openings adapted to receive connectors in the form of posts projecting from the housings of electrical parts to be included in circuits on the boards. One standard integrated circuit package, commonly called a 14-pin dual inline package, is formed with a small rectangular housing having 14 pins or posts arranged in parallel relation in two parallel rows of seven each on opposite sides of the housing. The illustrated assembly embodying the present invention similarly includes a housing 11 of flat rectangular shape with 14 connectors in the form of straight pins 12 arranged in parallel relation in two parallel rows of seven pins each on opposite sides of the housing, the planes of the rows of pins being spaced outwardly from the side edges of the housing and normal to planes including flat top and bottom outer surfaces of the housing.

Within the housing is a reed relay 13 with a reed switch 14 having two reeds 15 of magnetic material enclosed in .a hermetically sealed hollow tube 16 of insulating material such as glass and projecting inwardly in cantilever fashion from the ends of the tube and into spaced overlapping relation in the center of the tube, outer end portions 17 of the reeds projecting outwardly beyond the ends of the tube. Encircling the glass tube of the reed switch is a multiple-tum coil 18 of elongated cylindrical shape with terminals 19 on its exterior at opposite ends.

In accordance with the present invention, the connector pins 12 are fonned as a part of a frame 20 which is arranged in a novel manner with respect to the reed relay 13 to facilitate enclosure of the relay in the housing 11 and connection of the relay parts to'selected pins. To this end, the frame includes an elongated central opening 2l receiving the relay parts. Extending transversely of the frame and the central opening in parallel relation with each other are a plurality of elongated contact members 22. The contact members are arranged in two rows extending along opposite sides of the opening and the inner end portions 23 and inten'nediate portions 24 of the members are enlarged whereas the outer end portions are narrowed and form the connector pins 12. Extending transversely of the opening at its end portions are two flat crossbars 25 each of which is connected to the inner end portion of at least one of the contact members 22 adjacent to the end of the opening.

The contact members 22 and crossbars 25 of the frame are formed as parts of a flat blank 30 having a rectangular outer portion with side strips 26 integrally connected to the outer ends of the pins 12 and end strips 27 extending between the side strips. Longitudinal straps or bars 28 connect the intermediate portions 24 of the contact members 22 with each other and with the end strips. The entire blank is formed by a chemical milling process or other suitable process such as stamping from a sheet of conducting material on the order of 0.010 of an inch thick. The longitudinal straps not only provide a conducting connection between adjacent contact members exteriorly of the housing in the finished product, but also, they cooperate with the end strips to form a dam between the dies of a transfer mold for forming the housing so as .to confine the material used for the housing when it is in a liquid state. The inner end portions 23 of the contact members are located within the housing and, to form an anchor to prevent withdrawal of each contact member, each inner end portion is notched as indicated at 29. To facilitate differentiation of the parts of the frame of the finished assembly of FIG. 1 from the unused parts of the blank 30 not in the final assembly, the unused parts are shown in phantom in FlGS. 2, 3 and 4 along with the housing 11.

To permit connection of the outer end portions 17 of the reeds 15 of the switch 14 to the crossbars 25 of the frame 20 while locating the axis of the insulating tube 16 of the switch and the coil 18 in the plane of the frame, the outer end portion of each reed is offset slightly as indicated at 31 from that portion adjacent the insulating tube (See FlGS. 1 and 4). Also, to space the crossbars from the insulating tube, these pieces are offset outwardly from the centers of the contact members 22 to which they are connected. Suitable holes 32 are provided in the side strips 26 of the blank 30 to cooperate with pins in the transfer mold to locate the blank within the mold and another hole 33 is formed in the side strip adjacent one contact member to enable the order of the pins to be identified after the housing is formed.

in addition to the reed relay 13, the present assembly easily accommodates other parts such, for example, as either an integrated circuit (not shown) which may be combined with the relay to form a power amplifier or other switching circuits or an electrostatic shield in the form of a copper tube (not shown) encircling the insulating tube 16 within the coil 18. In

the present instance, where the reed switch 14 may be used with integrated circuit chips, a diode 34 is connected across the coil to dissipate the back EMF occurring when the coil circuit is opened such EMF being larger than an integrated circuit chip normally is capable of dissipating.

In the formation of the improved relay assembly 10, the reed relay l3 first is inserted into the longitudinal central opening 21 in the frame blank 30 and the outer ends 17 of the reeds 15 are soldered or welded to the crossbars 25 of the frame. Then, the terminals of the diode 34 and the terminals 19 of the coil 18 are secured by solder or weld joints to the inner ends 23 of two other contact members 22, in this instance, the contact members adjacent to the end contact members which are connected to the crossbars. If desired, before enclosing the reed relay within the housing 11, connection of each crossbar 25 to one of the adjacent contact members 22 may be broken by cutting out the connecting portion indicated at 35 (H6. 2) so as to leave the bar connected to only one contact member.

- After the parts to be included in the interior of the housing 11 are placed there in finished form and their subassembly with the frame blank 30 is completed, the subassembly is inserted between the two halves of a transfer mold. These halves engage opposite flat sides of the intermediate portions 24 of the contact members 22 adjacent to the exterior of the housing l1 which is indicated in phantom in FIG. 2, the longitudinal straps 28 connecting the intermediate portions,

and the center portions of the end strips 27 of the rectangular outer portion of the blank 30. The longitudinal straps, the intermediate portions of the contact members and the end strips then act as a dam to limit outward flow of the encapsulating material such as a suitable epoxy resin which is inserted into the mold in liquid form in a well-known manner and there is hardened to form the housing before separation of the mold parts.

After the housing material has hardened, the halves of the transfer mold are removed leaving the housing 11 with the exterior parts of the frame blank 30 still connected together and lying in the same plane. Also, exteriorly of the housing and between the housing and the darn formed in the mold by the longitudinal straps 28, the intermediate portions 24 of the contact members 22, and the end strips 27 of the blank are thin sections of hardened housing material or flash. This material is easily knocked out and the blank then is put into a trim die to remove those portions which are not desired in the final assembly. These unused portions which are shown in phantom in the drawings include the side and end strips 26 and 27 of the outer rectangular part of the blank as well as some or all of the longitudinal straps 28 connecting the end contact members to the end strips and some of the contact members with themselves. Once the excess parts of the frame blank 30 are removed, the housing 11 and remaining frame parts including the contact members 22 and selected ones of the longitudinal straps 28 are placed in a fixture where the intermediate portions 24 of the contact members are bent laterally at right angles to dispose their outer ends orterminal pins 12 in spaced parallel planes. This completes the final assembly as shown in HO. 1.

It will be apparent that the novel relay assembly 10 described above may be formed simply and easily with variations in the parts enclosed in the housing and cooperating with the reed relay 13. Also, the assembly may be plugged easily into sockets in control panels or in printed circuit boards and is interchangeable with other devices such as integrated circuit packages used with printed circuit boards. Moreover, the assembly is adapted readily to different patterns of the terminal pins l2, different sizes of pins for different sizes of pinholes, and different internal connections of parts to the various terminal pins.

Various other embodiments and modifications thereof in addition to those shown and described herein will be apparent to those skilled in the art. Such other embodiments are intended to fall within the scope of the appended claims.

lclaim:

l. A relay assembly having, in combination, an elongated thin, flat frame having an elongated central opening extending longitudinally of the frame and a plurality of elongated contact members extending transversely of the frame and the central opening in parallel with each other and arranged in two rows extending along opposite sides of the opening with their adjacent inner end portions defining the opening, two crossbars extending transversely of opposite end portions of said opening in the plane of said frame and each connected at atleast one end to the inner end portion of at least one of the contact members adjacent to the adjacent end of the opening, a reed switch comprising a tube of insulating material lying in said opening and a pair of elongated reeds of conducting material having their inner end portions projecting toward each other in cantilever fashion and into overlapping relation from opposite ends of the tube and their outer end portions projecting from opposite ends of the tube and electrically connected to said crossbars, a coil encircling said switch. and having tenninals connected separately to others of said contact members not connected to those members which are connected to the Crossbars, and an encapsulating body of insulating material enclosing said switch, said coil, said crossbars and the inner end portions of said contact members with intermediate and straight outer end portions of the members located exteriorly of the body and with the intermediate portions bent laterally to dispose the outer end portions in parallel planes normal to said plane, said frame being formed from a flat blank having longitudinal straps connecting said intermediate portions of said a contact members and end strips connecting end onesof the contact members in said rows and cooperating with the longitudinal straps and the intermediate portions of the members to define a dam in a mold for material forming said body, said end strips and certain of said straps being removed from the final product to interrupt the electrical connections between adjacent ones of said contact members exteriorly of said body.

2. A relay assembly having, in combination, an elongated thin, flat frame having an elongated central opening extending longitudinally of the frame and a plurality of elongated contact members extending transversely of the frame and the central opening in parallel with each other and arranged in two rows extending along opposite sides of the opening with their adjacent inner end portions adjacent said opening, a reed switch comprising a tube of insulating material lying in said opening and a pair of elongated reeds of conducting material having their inner end portions projecting toward each other 'in cantilever fashion and into overlapping relation from opposite ends of the tube and their outer end portions projecting outwardly from opposite ends of the tube and electrically connected to adjacent ones of said contact members, a coil encircling said switch and having terminals connected separately to others of said contact members not connected to said reeds, and an encapsulating body of insulating material enclosing said switch, said coil, and the inner end portions of said contact members with intermediate and straight outer end portions of the members located exteriorly of the body and with the intermediate portions bent laterally to dispose the outer end portions in parallel planes normal to the plane of said frame, said frame being formed from a flat blank having longitudinal straps connecting said intermediate portions of said contact members and end strips connecting end ones of said contact members in said rows and cooperating with the longitudinal straps and the intermediate portions of the members to define a dam in a mold for material forming said body, said end strips and certain of said straps being removed from the final product to interrupt the electrical connections between adjacent'ones of said contact members exteriorly of said body.

3. The assembly of claim 2 in which a diode is connected in parallel across said coil.

4. The assembly of claim' 2 in which at least one other circuit element is enclosed within said housing and is connected to one of said contact members not connected to said switch.

5. A switch assembly comprising, in combination, an elongated thin, flat frame having an elongated central opening extending longitudinally of the frame and a plurality of elongated contact members extending transversely of the frame and the central opening in parallel with each other and arranged in two rows extending along opposite sides of the opening with their adjacent inner end portions adjacent to said opening, a reed switch having movable contacts within an enclosure lying in said opening and generally aligned therewith, said reed switch having outer conductive portions projecting outwardly from said enclosure and respectively electrically connecting said movable contacts to respective ones of said contact members, and an encapsulating body of insulating material enclosing and molded about said switch and the inner end portions of said contact members with intennediate and straight outer end portions of the members located exteriorly of the body and with-the intermediate portions bent laterally to dispose the outer end portions in parallel planes normal to the plane of said frame, said frame being formed from a flat blank having strips extending longitudinally of said elongated opening and connecting adjacent contact members in each of said rows and end strips extending transversely of the elongated opening and interconnecting said two rows of contact members, at least portions of said strips being removed from the final product.

6. The switch assembly of claim 5 wherein a plurality of adjacent contact members in one of said rows are electrically interconnected in the final product.

10. The switch assembly according to claim 5 further comprising two crossbars extending transversely of opposite end portions of said opening in said frame and each connected at at least one write the inner end portion of at least one of the contact members adjacent to the adjacent end of the opening, the outer conductive portions of said switch projecting from opposite ends of the enclosure and being electrically connected to said crossbars, othersof said contact members not being connected to those memberswhich are connected to the crossbars, and said crossbars being within said encapsulating body of insulating material.

Claims

1. A relay assembly having, in combination, an elongated thin, flat frame having an elongated central opening extending longitudinally of the frame and a plurality of elongated contact members extending transversely of the frame and the central opening in parallel with each other and arranged in two rows extending along opposite sides of the opening with their adjacent inner end portions defining the opening, two crossbars extending transversely of opposite end portions of said opening in the plane of said frame and each connected at at least one end to the inner end portion of at least one of the contact members adjacent to the adjacent end of the opening, a reed switch comprising a tube of insulating material lying in said opening and a pair of elongated reeds of conducting material having their inner end portions projecting toward each other in cantilever fashion and into overlapping relation from opposite ends of the tube and their outer end portions projecting from opposite ends of the tube and electrically connected to said crossbars, a coil encircling said switch and having terminals connected separately to others of said contact members not connected to those members which are connected to the crossbars, and an encapsulating body of insulating material enclosing said switch, said coil, said crossbars and the inner end portions of said contact members with intermediate and straight outer end portions of the members located exteriorly of the body and with the intermediate portions bent laterally to dispose the outer end portions in parallel planes normal to said plane, said frame being formed from a flat blank having longitudinal straps connecting said intermediate portions of said contact members and end strips connecting end ones of the contact members in said rows and cooperating with the longitudinal straps and the intermediate portions of the members to define a dam in a mold for material forming said body, said end strips and certain of said straps being removed from the final product to interrupt the electrical connections between adjacent ones of said contact members exteriorly of said body.

2. A relay assembly having, in combination, an elongated thin, flat frame having an elongated central opening extending longitudinally of the frame and a plurality of elongated contact members extending transversely of the frame and the central opening in parallel with each other and arranged in two rows extending along opposite sides of the opening with their adjacent inner end portions adjacent said opening, a reed switch comprising a tube of insulating material lying in said opening and a pair of elongated reeds of conducting material having their inner end portions projecting toward each other in cantilever fashion and into overlapping relation from opposite ends of the tube and their outer end portions projecting outwardly from opposite ends of the tube and electrically connected to adjacent ones of said contact members, a coil encircling said switch and having terminals connected separately to others of said contact members not connected to said reeds, and an encapsulating body of insulating material enclosing said switch, said coil, and the inner end portions of said contact members with intermediate and straight outer end portions of the members located exteriorly of the body and with the intermediate portions bent laterally to dispose the outer end portions in parallel planes normal to the plane of said frame, said frame being formed from a flat blank having longitudinal straps connecting said intermediate portions of said contact members and end strips connecting end ones of said contact members in said rows and cooperating with the longitudinal straps and the intermediate portions of the members to define a dam in a mold for material forming said body, said end strips and certain of said straps being removed From the final product to interrupt the electrical connections between adjacent ones of said contact members exteriorly of said body.

4. The assembly of claim 2 in which at least one other circuit element is enclosed within said housing and is connected to one of said contact members not connected to said switch.

5. A switch assembly comprising, in combination, an elongated thin, flat frame having an elongated central opening extending longitudinally of the frame and a plurality of elongated contact members extending transversely of the frame and the central opening in parallel with each other and arranged in two rows extending along opposite sides of the opening with their adjacent inner end portions adjacent to said opening, a reed switch having movable contacts within an enclosure lying in said opening and generally aligned therewith, said reed switch having outer conductive portions projecting outwardly from said enclosure and respectively electrically connecting said movable contacts to respective ones of said contact members, and an encapsulating body of insulating material enclosing and molded about said switch and the inner end portions of said contact members with intermediate and straight outer end portions of the members located exteriorly of the body and with the intermediate portions bent laterally to dispose the outer end portions in parallel planes normal to the plane of said frame, said frame being formed from a flat blank having strips extending longitudinally of said elongated opening and connecting adjacent contact members in each of said rows and end strips extending transversely of the elongated opening and interconnecting said two rows of contact members, at least portions of said strips being removed from the final product.

7. The switch assembly according to claim 5 comprising magnetic field producing means in proximity to said switch and having terminals connected separately to others of said contact members not connected to said switch.

8. The switch assembly according to claim 7 wherein said encapsulating body encloses said magnetic field producing means.

9. The switch assembly of claim 7 wherein said magnetic field producing means comprises a coil encircling said switch.

10. The switch assembly according to claim 5 further comprising two crossbars extending transversely of opposite end portions of said opening in said frame and each connected at at least one end to the inner end portion of at least one of the contact members adjacent to the adjacent end of the opening, the outer conductive portions of said switch projecting from opposite ends of the enclosure and being electrically connected to said crossbars, others of said contact members not being connected to those members which are connected to the crossbars, and said crossbars being within said encapsulating body of insulating material.