US3568310A

US3568310A - Hermaphroditic multi-contact reed switch

Info

Publication number: US3568310A
Application number: US816990A
Authority: US
Inventors: Ralph E Neuber
Original assignee: Sylvania Electric Products Inc
Current assignee: GTE Sylvania Inc
Priority date: 1968-03-14
Filing date: 1969-04-17
Publication date: 1971-03-09
Anticipated expiration: 1988-03-09

Abstract

A HERMAPHRODITIC MULTI-CONTACT REED SWITCH INCLUDES A TUBULAR ENVELOPE HAVING A PAIR OF SUBSTANTIALLY IDENTICAL HEADERS SEALED INTO THE OPPOSITE ENDS AND CONTAINS AN INERT ATMOSPHERE. EACH OF THE HEADERS INCLUDES A PLURALITY OF SWITCH MEMBERS HAVING A MAGNETIZABLE PORTION EXTENDING INTERIORLY OF THE ENVELOPE AND IN LONGITUDINALLY OVERLAPPING RELATIONSHIP WITH THE MAGNETIZABLE PORTION OF THE SWITCH MEMBERS OF THE OPPOSITE HEADER. THE LONGITUDINAL

OVERLAPPING MAGNETIZABLE PORTIONS OF THE MATCHING SWITCH MEMBERS OF THE OPPOSING HEADERS HAVE A DESIRED GAP THEREBETWEEN WHICH IS DEPENDENT UPON THE CIRCUMFERENTIAL DISPLACEMENT OF ONE HEADER WITH RESPECT TO THE OTHER.

Description

Mgrch 9 l 97 l RQENEUBEk y 3,568,310

HERMAPHRODITIC MUL'I'I-CONTAC'I' REED SWITCH Original filed Marah 14, 1968 2 Sheets-She et 1 INVENTOR. RALPH E. NEUBER v w iD- ATTOR NET March 9, 1971 i R. E. NEUBER 3,563,310

Q I HERMAPHRODITIC MULTI-CONTACT REED SWITCH Original Filed March 14, 1968 2 Sheets-Sheet 2 FORM A PAIR OF SIMILAR HEADERS INCLUDING AN INSULATOR AND SWITCH MEMBERS CIRCUMFERENTIALLY'ROTATE ONE HEADER wnu RESPECT TO THE OTHER HERMET ICALLY SEAL HEADERS IN OPPOSITE ENDS OF TUBULAR ENVELOPE INVENTOR. RALPH E. NEUBER m CIJ ATTORNEY United States Patent 3,568,310 HERMAPHRODITIC MULTI-CONTACT REED SWITCH Ralph E. Neuber, Seneca Falls, N.Y., assignor to Sylvania Electric Products Inc.

Original application Mar. 14, 1968, Ser. No. 713,216, now Patent No. 3,471,813, dated Oct. 7, 1969. Divided and this application Apr. 17, 1969, Ser. No. 816,990

Int. Cl. H01h 11/00 US. Cl. 29-622 2 Claims ABSTRACT OF THE DISCLOSURE A hermaphroditic multi-contact reed switch includes a tubular envelope having a pair of substantially identical headers sealed into the opposite ends and contains an inert atmosphere. Each of the headers includes a plurality of switch members having a magnetizable portion extending interiorly of the envelope and in longitudinally overlapping relationship with the magnetizable portion of the switch members of the opposite header. The longitudinal overlapping magnetizable portions of the matching switch members of the opposing headers have a desired gap therebetween which is dependent upon the circumferential displacement of one header with respect tothe other.

CROSS-REFERENCE TO RELATED APPLICATION This application is a division of S.N. 713,216, filed Mar. 14, 1968, now US Pat. 3,471,813 which issued Oct. 7, 1969, and assigned to the assignee of the present invention.

BACKGROUND OF THE INVENTION The prior art suggests numerous so-called reed switches wherein a pair of magnetizable contact members are disposed in overlapping spaced relationship with in an envelope and activated by application of controllable magnetic field. Also, the prior art suggests numerous similar devices wherein a number of such contacting members are included within the same envelope.

Although many of the above-mentioneddevices have provided excellent service in numerous applications, it has been found that there are certain applications wherein the known structure leaves something to be desired. More specifically, it has been found that known reed switch structures usually include switch members sealed into the ends of the envelope which tends to provide a non-uniform seal and a non-uniform spacing intermediate the mag- 0 netizable switch members. Also, such sealing techniques wherein glass-to-metal seals, for example, are employed require delicate controls to prevent oxidation of the metal switch members. Moreover, all of the switch members of the known multiple-contact devices are not concentric with respect to the envelope and to the energizing means surrounding the envelope which tends to cause a nonuniform magnetic field intensity insofar as a multiplecontact device is concerned.

OBJECTS AND SUMMARY OF THE INVENTION for the contacts of a hermaphroditic multi-contact reed switch. These and other objects and advantages are achieved 1n one aspect of the invention by a hermaphroditic multicontact reed switch having a pair of substantially identical headers each including an insulator support and a plurality of switch members embedded therein and extending therethrough. The headers are circumferentially displaced with respect to one another and sealed into opposite ends of a tubular envelope to provide a spaced longitudinal overlapping of the switch members which are activated by a magnetic field developing means surrounding the envelope.

The hermaphroditic multi-contact reed switch is constructed by a process which includes fabricating a pair of substantially identical headers, circumferentially rotating the headers with respect to one another, and hermetically sealing the headers into opposite ends of a tubular envelope.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a preferred embodiment of a hermaphroditic multi-contact reed switch;

FIG. 2 is a plan view of the embodiment of FIG. 1, and

FIGS. 3, 4 and 5 are embodiments of headers suitable for the embodiment of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and accompanying drawings.

Referring to the drawings, FIG. 1 illustrates a hermaphroditic four-contact reed switch. The switch includes a tubular envelope 7 of a material such as glass and has a pair of opposite ends 9 and 11. A pair of substantially similar headers, 13 and 15 are hermetically sealed into the opposite ends 9 and 11 of the envelope 7.

The

headers

13 and 15 each include an insulator support 17 such as glass, wherein a plurality of switch members 19 are embedded. The switch members 19 each include a magnetizable portion 21 which is flexible and of a material such as iron or a nickel-iron alloy and extends interiorly of the envelope 7. Also, each of the switch members 19 includes a connector portion 23 extending exteriorly of the envelope 7 to provide an electrical connecting means.

Further, the longitudinal axis of each of the magnetizable portions 21 is displaced from the longitudinal axis of the connector portions 23 in a direction substantially normal to these longitudinal axes. Also, the displacement of each of the magnetizable portions 21 from the longitudinal axis of the connector portion 23 is substantially one-half the total desired gap 25 or distance intermediate a pair of magnetizable portions 21.

In this particular embodiment, the four switch members 19 are spaced in quadrature as illustrated in the plan view of FIG. 2. These quadrature spaced switch members 19 form two diametrically opposing pairs with the magnetizable portions 21 of one pair formed such that the diametric distance X between the longitudinal axes thereof is greater than the diametric distance Y between the longitudinal axes of the connector portions 23. The other pair is formed in an opposite fashion in that the diametric distance A between the longitudinal axes of the magnetizable portions 21 is less than the diametric distance 8 between the longitudinal axes of the connnector portions 23.

As mentioned above, the

headers

13 and 15 are hermetically sealed to opposite ends 9 and 11 of the envelope 7, and provide a longitudinal overlapping of the magnetizable portion 21 of the switch members 19 extending interiorly of the envelope 7 from each of the

headers

13 and 15. Also, the

headers

13 and 15 are in circumferentially displaced relationship with respect to one another to provide a desired gap 25 or distance intermediate each pair of longitudinally overlapping magnetizable portions 21. In this particular instance, the circumferential relationship is a quadrature relationship although it is obvious that other switch member forms and circumferential relationships are applicable and appropriate.

The pairs of magnetizable portions 21 forming each one of the gaps 25 are equi-distantly spaced from the circumference of the tubular envelope 7 and a magnetic field developing means 27 such as an electromagnet for instance, surrounds the tubular envelope 7. Thus, each pair of magnetizable portions 21 of the switch members 19 is equi-distantly spaced from the magnetic field developing means 27 and subjected to substantially the same magnetic field intensity.

Referring back to the

headers

13 and 15, FIGS. 3, 4, and illustrate several suitable embodiments. In FIG. 3 a plurality of switch members 29 are embedded in and pass through an insulator 31 such as glass. Each of the switch members 29 has a magnetizable portion 33 and a connector portion 35 which extend outwardly in Opposite directions from the insulator 31. Also, the magnetizable portion 33, which is both magnetic and flexible, is formed such that the insulator 31 serves as a rigid and uniform base whereon the cantilevered magnetizable portion 33 bends.

FIG. 4 is a structure somewhat similar to FIG. 2. Herein, each of the switch members 29 has beads 37 of the same material as the insulator 31 bonded to the insulator 31 and surrounding, supporting and sealed to both the magnetizable and

connector portions

33 and 35 respectively. Also, a tubular exhaust stem 39 is affixed to the insulator 31 in a manner well known in the art to provide a means for replacing the atmosphere of the device with desired inert atmosphere.

Also, FIG. 5 illustrates a plurality of switch members 29 sealed into and passing through an insulator 31 and a button 41 bonded thereto. In this instance, the button 41 not only enhances the rigidity and sealing of the switch members 29 but also serves to protect the seal intermediate the switch members 29 and insulator 31 from thermal shock upon application of heat, soldering for instance, to the switch members 29.

As to the construction of a hermaphroditic multi-contact reed switch, reference is made to the flow chart of FIG. 6. Therein, a plurality of similar headers are fabricated by sealing a plurality of switch members including magnetizable and connector portions into an insulator. Obviously, the switch members are preferably of the preformed variety but may be formed after embedment in the insulator. Also, the formed switch members are readily adapted to both spacing adjustment and cleaning after having been sealed into the insulator.

Then a pair of the headers are circumferentially rotated with respect to one another to provide a desired gap intermediate associated pairs of magnetizable portions. This pair of headers is hermetically sealed to opposite ends of a tubular envelope which, in the preferred embodiment, involves a glass-to-glass sealing technique and a relatively small distortion of the envelope to provide contact thereof with the headers. Moreover, the atmosphere Within the envelope may then be replaced by a dry inert atmosphere utilizing an exhaust tube in a manner well-known in the art.

Thus, there has been provided a unique hermaphroditic 4 multi-contact reed switch having numerous advantages over other known reed switches. The multi-contact switch is volumetrically efficient as compared with single-contact devices providing a consequent reduction in cost per contact. Also, the header-type construction lends itself to the formation of a rigid and uniform support whereon the flexible magnetizable portion of the switch members is dependent. Further, the header-type construction provides individual sealing of the switch members to the headers and hermetic sealing of the headers to the envelope which not only permits cleaning and adjustment of the switch membersbut also a relatively small distortion of the envelope wherein the headers are hermetically sealed. Additionally, the header-type construction facilitates circumferential displacement of the headers with respect to one another prior to scaling and enhances compensation for distortion of the switch members due to handling and transfer during fabrication.

Moreover, the hermaphroditic form of the headertype construction is economical of apparatus, time, and inventory of parts.

While there has been shown and described what is at present considered the preferred embodiments of the in vention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention as defined by the appended claims.

I claim: 1. A hermaphroditic multi-contact reed switch fabricating process comprising the steps of:

forming a pair of substantially similar headers, each header having an insulator with four switch members identically arranged thereabout and embedded therein and extending therethrough, said switch members being spaced in quadrature relationship forming two diametrically opposing pairs, one of said pairs having a larger diametrical spacing than the other;

aligning and overlapping opposing pairs of switch members having different diametrical spacings by juxtaposing the headers with respect to each other; and

hermetically sealing said pair of headers in opposite ends of a tubular envelope to provide a longitudinal overlapping of the switch members of said pair of headers, whereby said overlapping switch members have gaps therebetween and said gaps are disposed a uniform radial distance from said envelope circumference.

2. The fabricating process of claim 1 including the step of replacing the atmosphere or said envelope with a dry and inert atmosphere.

References Cited UNITED STATES PATENTS 2,407,742 9/ 1946 Harries 29-25.16 2,411,548 11/1946 Laico 29-25. 16X 2,204,217 6/1940 Herriger 2925.16X 2,225,465 12/ 1940 Scharfnagel 29-25.16 3,134,868 5/1964 Shine.

3,248,498 5/ 1966 Thompson.

JOHN F. CAMPBELL, Primary Examiner R. W. CHURCH, Assistant Examiner US. 01. X.R.