Switching device

• US 3,904,999 A
• Filed: 06/07/1974
• Issued: 09/09/1975
• Est. Priority Date: 06/07/1974
• Status: Expired due to Term

• Current Assignee: Donald S. Rich, Norman Rudnick
• Original Assignee: Donald S. Rich, Norman Rudnick
• Inventors: Rich, Donald S., Rudnick, Norman
• Primary Examiner(s): Broome, Harold
• Application Number:
  US05/477,430
• Time in Patent Office: 459 Days
• Field of Search: 335/49,50,51,52,53,55,56 200/191,195,175,209,214
• US Class Current: 335/52
• CPC Class Codes: H01H 29/18 with level of surface of contact liquid displaced by non-electrical contact-making plunger
• CPC Class Codes: H01H 50/20 movable inside coil and substantially lengthwise with respect to axis thereof; movable coaxially with respect to coil

Abstract

Disclosed is a switch housing having a generally cylindrical shape. Cylindrically shaped magnetically permeable and electrically conductive end members or caps are joined to one another by a cylindrically shaped, electrical nonconductive, magnetically impermeable sleeve. The end members or caps and sleeve enclose a cylindrically shaped cavity. One end member or cap, within the cavity, has a substantially hemispheric depression. In registry with the cap hemispheric depression and movable relative thereto is the hemispheric depression of a magnetically responsive, cylindrically shaped, substantially electrically non-conductive armature. Communicating with the armature hemisphere and extending axially therefrom and within the armature is a frusto-conically shaped recess. A cylindrical aperture provides an opening from the frusto end of the cone to the end of the armature opposed to the hemispheric end. A first electrical contact is defined by the axially aligned end cap having the hemispheric recess therein. The recess may be selectively wetted to effect electrical contact with mercury disposed in the sphere defined by the armature and housing recesses. A second electrical contact is an integral part of the second end cap and includes an axially extending portion within the cavity which projects into the cylindrical aperture of the armature.

Claims

1. A switch comprising:

a. housing means having a cavity therein;

b. an electrically conductive liquid within said cavity;

c. an armature means within said cavity and movable relative to said housing;

said armature means and said housing defining within said cavity a chamber;

said chamber comprises at least a first and second part;

said first part of said chamber being joined to said second part at a common port;

the volume of said first part of said chamber being dependent upon said relative position of said armature means such that with said armature means in a first position, said liquid conductor is retained substantially within said first part of said chamber;

with said armature means being at least in a second position, said armature means displaces at least a part of said liquid conductor from said first part into said second part of said chamber;

said port being so dimensioned such that, with said armature means being in said first position, said volume of said first part in combination with the forces of surface tension upon said liquid conductor and the volume of said liquid conductor within said first part, thereby resulting in said liquid conductor being retained substantially in said first part;

upon said armature means moving relative to said housing to and from said second position, said port admitting said displaced liquid conductor between said first and second parts of said chamber;

said first part being defined by at least walls of said housing and said armature means;

said second part comprises walls of said arMature means exclusive of said housing walls;

d. at least first and second electrical contacts communicating with said chamber from without said housing;

said armature means in at least one of said relative positions, causing said liquid conductor to couple said electrical contacts and, in another of said relative positions said liquid conductor not coupling said contacts; and

e. means for moving said armature means relative to said housing thereby coupling or uncoupling said contacts to operate said switch.

2. A switch as recited in claim 1, wherein said first part comprises said housing having a recess therein for receiving said liquid conductor.

3. A switch as recited in claim 2, wherein said armature means comprises a member having a first recess therein;

said armature recess in combination with said housing recess and said housing walls define said first part.

4. A switch as recited in claim 3, wherein said armature means further comprises a second recess in communication with said first recess, said communication being defined by said port, said second recess comprises said second part of said chamber.

5. A switch as recited in claim 4, wherein said first recess in said armature member and said housing means recess define, with said armature in said first position, a sphere;

said armature member first recess and said housing recess each being a segment of a sphere less than a hemisphere.

6. A switch as recited in claim 5, wherein said armature member second recess is defined by walls lying in at least three intersecting planes;

said port being opposed to the apex formed by said intersecting planes.

7. A switch as recited in claim 6, wherein said second electrical contact extending from said housing and into said second part of said chamber and said armature member moves relative to said first and second contacts.

8. A switch as recited in claim 7, further comprises a gas within said cavity;

said armature means having an aperture communicating with said second recess and said cavity;

said second contact passing freely through said aperture so as to come into electrical contact with said liquid conductor with said armature means being in said second position;

said second contact and said aperture defining therebetween a space of sufficiently small cross-sectional dimension as to inhibit the flow of said liquid conductor and to pass therebetween said gas so as to vent said chamber of said gas as said liquid conductor moves into and out of said second part.

9. A switch as recited in claim 8, wherein said armature means in combination with said housing defines therebetween a passageway between said armature means aperture and said first part of said chamber to recirculate any of said liquid conductor passing between said second electrical contact and said aperture, out of said chamber, and within said cavity.

10. A switch as recited in claim 9, wherein said armature means second recess is substantially frusto-conically shaped, said aperture being substantially cylindrically shaped and extending from the frusto end of said cone, said second contact being substantially cylindrically shaped.

11. A switch as recited in claim 10, wherein said housing cavity is substantially rod-shaped and said armature means relative movement being coaxial with the principal axis of said housing;

said means for moving said armature means relative to said housing comprises magnetic means;

said armature means comprises magnetically responsive means.

12. A switch as recited in claim 11, wherein said housing comprises a hollow cylindrical body, closed at opposed ends by first and second radially extending planar walls, said cavity being substantially cylindrically shaped, said armature means being substantially cylindrically shaped and complementing the cylindrical walls of said housing defining said housing cavity;

said housing hemispherical recess residing in said first planar radially extending end of said cavity;

said hemispherical recess of said armatuRe being within a planar and radially extending end of said armature;

said frusto-conical recess and cylindrical aperture extending axially from said armature hemisphere.

13. A switch as recited in claim 12, wherein said armature member comprises a magnetically responsive cylindrical sleeve enclosing an electrically non-conductive body portion;

said armature having flattened portions along the length thereof;

said flattened portion comprises said passageway;

said armature having a planar radially extending end opposed to said end having said hemisphere therein;

said planar end of said armature abutting said second planar end surface of said housing with said armature in said first position;

said ends of said cylindrical housing being magnetically responsive;

said one contact extending axially from said second end surface;

insulating means affixed to said second planar end surface of said housing so as to inhibit electrical contact between said armature and said housing end.

14. A switch as recited in claim 13, wherein said housing ends comprise first and second end members and a cylindrical nonmagnetic, magnetically impermeable sleeve member;

said first housing end member being electrically conductive;

said first electrical contact comprises said first end member thereby forming an axially extending electrical contact.

15. A switch as recited in claim 14, wherein at least a portion of said hemispheric base recess being wettable by said liquid conductor, thereby comprising a part of said first electrical contact, said second contact being wettable by said liquid conductor.

16. A switch as recited in claim 15, wherein said sleeve member is an electrically conductive material affixed to said end members and electrically insulated from at least one of said end members.

17. A switch as recited in claim 16, wherein said sleeve member is electrically nonconductive material and affixed to said end members.

18. A switch as recited in claim 15, wherein said second contact comprises an integral part of said second end member.

19. A switch as recited in claim 18, wherein said first and second end members each comprise first exterior electrical contact portions of electrically conductive material and having a cylindrical shape and a second, larger diameter axially aligned electrically conductive cylindrically shaped body portion;

one of said body portions having extending therefrom a cylindrically shaped axial extension terminating in said hemispheric recess end;

the other of said body portions having extending therefrom a cylindrically shaped axial extension terminating in said second contact;

said sleeve having an inner diameter sufficient to envelope said extensions and be secured thereto to form in combination therewith said housing;

said sleeve having an outer diameter equal to the diameter of said body part outer diameters;

said liquid conductor is mercury;

said magnetic means is a coil.

20. A switch comprising:

a. a housing having a cavity therein and defined at least by a principal axis extending substantially the length thereof;

b. an electrical conductive liquid within said cavity;

c. armature means within said cavity and movable relative thereto;

said armature means and said housing defining within said cavity a chamber;

said chamber comprises a first and second part;

said first part of said chamber retaining therein said liquid conductor;

said first and second parts being conjoined at a common port;

said port being capable of permitting said liquid conductor to pass freely between said parts in dependence upon said relative position of said armature means;

d. at least a first and second electrical contacts communicating with said chamber from without said housing and disposed substantially along an axis, said axis being substantially parallel to said principal axis;

said armature means in at least one of said respective positions, causing said liquid conductor to couple said contacts and in another of said rElative positions of said armature means said liquid conductor not coupling said contacts; and

e. means for moving said armature means relative to said housing thereby coupling and uncoupling said contacts so as to operate said switch.

21. A switch as recited in claim 20, wherein said housing cavity having rod-like shape.

22. A switch as recited in claim 21, wherein said first contact communicates with said first part and said second contact communicates with said second part of said chaamber.

23. A switch as recited in claim 22, wherein said volume of said first part of said chamber being dependent upon said relative position of said armature means such that with said armature means in a first position, said liquid conductor being retained substantially within said first part of said chamber;

with said armature means being at least in a second position, said armature means displaces at least a part of said liquid conductor from said first part into said second part of said chamber;

said port being so dimensioned such that, with said armature means being in said first position, said volume of said first part in combination with the surface tension of said liquid conductor and the volume of said liquid conductor within said first part of said chamber, thereby resulting in said liquid conductor being retained substantially in said first part; and

with said armature means moving relative to said housing to and from said second position, said port admitting said liquid conductor to between said first and second parts of said chambers said movement of said displaced liquid conductor being substantially in a path along said parallel axis.

24. A switch as recited in claim 23, wherein said parallel axis being coincident with said principal axis and said principal axis defining the principal axis of said rod-like cavity.

25. A switch as recited in claim 24, wherein said first part comprises walls of said housing and said armature means and said second part comprises walls of said armature means exclusive of said housing walls.

26. A switch as recited in claim 25, wherein said first part of said chamber being defined by at least a recess within said housing and said second part being defined by a recess within said armature means;

said second contact being in communication with said second part such that upon said armature means displacing at least a part of said liquid conductor into second part said contacts being coupled.

27. A switch as recited in claim 26, wherein said first and second contact ends are spaced axially from one another.

28. A switch as recited in claim 27, wherein said armature means having a recess which in combination with said housing recess and said housing walls defines said first part of said chamber.

29. A switch as recited in claim 28, wherein said housing cavity is substantially cylindrical, said armature means comprises a magnetically responsive member, cylindrical in shape complementing said cylindrical cavity;

said means for moving said armature means comprises a coil about the exterior of said housing;

said armature means moving in response to magnetic flux provided by said coil;

said recess in said housing comprising a segment of a sphere substantially approximating a hemisphere, said armature having in a planar radially extending surface in registry with said housing hemisphere and having a recess therein of substantially the same dimensions as said hemisphere housing recess so that in said first position of said armature said hemisphere recesses in combination with a space therebetween define a sphere;

said second part comprising a frusto-conical portion with the base thereof intersecting said armature hemisphere and a cylindrical aperture extending axially and receiving therein said second contact;

a gas within said cavity;

said second contact and said aperture defining therebetween a space for venting said gas;

said armature having in the cylindrical surface, axially extending flattened portions to form passageways For recirculation of liquid conductor between said aperture and said first part of said chamber;

said housing cylindrical wall about said cavity being substantially nonmagnetic and at the opposed ends of said cavity, said housing walls being magnetically impermeable.