Tilt switch and holder

• US 4,135,067 A
• Filed: 10/28/1976
• Issued: 01/16/1979
• Est. Priority Date: 03/30/1976
• Status: Expired due to Term

• Current Assignee: Polaron Engineering Limited (Eaton Corporation PLC.)
• Original Assignee: Fifth Dimension, Inc.
• Inventors: Bitko, Sheldon S.
• Primary Examiner(s): Scott, James R.
• Application Number:
  US05/736,773
• Time in Patent Office: 810 Days
• Field of Search: 200/61.47, 200/61.52, 200/182, 200/215-219, 200/220-226, 200/233, 200/235, 200/236, 200/186, 200/83 F, 200/211, 335/47-58
• US Class Current: 200/61.52
• CPC Class Codes: H01H 2300/016 Application timepiece
• CPC Class Codes: H01H 29/20 operated by tilting contact-liquid container

Abstract

An omnidirectional tilt switch includes an enclosure for a gravity response conductive ball. An annular shelf surrounds a central depression where at least one switch contact passing into the housing is exposed. The shelf is operable to support the ball in a position resting against a cup-shaped portion of the switch housing, with the ball centroid located within a imaginary right cylinder having the inner shelf periphery as a base. In response to tilting of the switch, the ball is movable away from the cup-shaped housing to the depression where it engages the aforementioned contact and closes a circuit between that and another contact.

A switch holder mounts the switch on a substrate located, for example, in an electro-optical display-type watch. The holder includes a base with a positioning edge or surface and tabs for securing the base to the substrate. Remote from the positioning edge or surface, the switch is supported at an angle relative to the positioning edge or surface.

Claims

1. A tilt switch comprising:

a gravity responsive conductive ball;

housing means defining an enclosure for said gravity responsive conductive ball and including at least one portion of insulative material;

inwardly extending annular shelf means in said enclosure adjacent one end of said housing means;

means defining a depression within said enclosure adjacent said one end of said housing means and surrounded by said annular shelf;

contact means including at least one switch contact extending through said at least one portion of insulative material of said housing means and exposed at said depression and further including at least one additional switch contact located within said enclosure and insulated from said at least one switch contact;

said annular shelf means being operable to support said conductive ball in a position where the ball rests against a portion of said housing means projecting beyond said shelf means, with the centroid of said ball located within an imaginery right cylinder having the inner periphery of said shelf means as a base; and

said ball being movable in response to the orientation of said switch, to a position unsupported against said portion of said housing means and in contact with both said at least one contact exposed at said depression and said at least one additional switch contact.

2. The tilt switch according to claim 1 wherein:

said at least one additional switch contact also extends through said at least one portion of insulative material of said housing means and is exposed at said depression.

3. The tilt switch according to claim 2 wherein:

said means defining said depression is dimensioned such that said ball is receivable in said depression out of contact with said shelf means.

4. The tilt switch according to claim 1 wherein:

said movable conductive ball is a ball of mercury; and

said at least one switch contact comprises a pointed electrode with a mercury-wettable tip.

5. The tilt switch according to claim 1 wherein:

said annular shelf means constitutes said at least one additional switch contact comprising an inwardly sloping ledge terminating in a narrow annular edge; and

said movable conductive ball is dimensioned relative to the diameter of said narrow annular edge to preclude passage into said depression completely out of contact with said shelf means.

6. The tilt switch according to claim 5 wherein:

said movable conductive ball is a ball of mercury; and

said at least one switch contact comprises a pointed electrode with a mercury-wettable tip.

7. The tilt switch according to claim 1 wherein:

said movable conductive ball is a ball of mercury; and

said at least one switch contact comprises a pointed electrode with a mercury-wettable tip.

8. A tilt switch comprising:

a gravity responsive conductive ball;

housing means defining an enclosure for said gravity responsive conductive ball and including at least one portion of insulative material;

annular knife-edge support means disposed in said enclosure adjacent one end of said housing means;

means defining a depression within said enclosure adjacent one end of said housing means and surrounded by said annular knife-edge support means;

contact means including at least one switch contact extending through said at least one portion of insulative material of said housing means and exposed at said depression and further including at least one additional switch contact located within said enclosure and insulated from said at least one switch contact;

said knife-edge support means being operable to support said conductive ball in a position resting against a portion of said housing means projecting beyond said knife-edge support means, with the centroid of said ball located within an imaginary right cylindrical projection of said knife-edge support means;

said ball being movable, in response to orientation of said switch, to a position unsupported against said portion of said housing means in contact with both said at least one contact exposed at said depression and said at least one additional contact.

9. The tilt switch according to claim 8 wherein:

said annular knife-edge support means present a conductive edge constituting said at least one additional contact; and

said movable conductive ball has a diameter of a size relative to the diameter of said annular knife-edge precluding passage to said depression completely out of contact with said conductive edge.

10. The tilt switch according to claim 9 wherein:

said movable conductive ball is a ball of mercury.

11. The tilt switch according to claim 10 wherein:

said at least one switch contact comprises a pointed electrode with a mercury-wettable tip.

12. A tilt switch comprising:

a housing defining an enclosure and including a cuplike cap section, and header means connected to said cap section for sealing said enclosure;

said header means including an inwardly extending, peripheral flange portion and a central closure portion of insulating material sealed within said peripheral portion;

said inwardly extending flange portion presenting an inwardly extending annular shelf defining by an inwardly sloping ledge terminating in a narrow annular edge;

said central closure portion being recessed relative to said shelf to define a depression surrounded by said edge;

contct means including at least one electrode extending through said central closure portion of insulating material and exposed at said depression, and at least one additional contact located within said enclosure and insulated from said at least one electrode;

a substantially ball-shaped conductive element in said enclosure movable freely in response to the orientation of the switch between a first position wherein it is not operable to close an electrical circuit between said at least one electrode and said at least one additional contact and a second position wherein it is operable to close and electrical circuit between said at least one electrode and said at least one additional contact;

said conductive element being operable to assume said first position when the switch is oriented within a solid angle including a generally upright position and assuming said second position when the switch is oriented outside said solid angle;

said edge of said ledge constituting fulcrum means for supporting said conductive element in a condition of unstable equilibrium such that said switch is operable to toggle between two states corresponding to said first and second positions;

said conductive element, said cap section and said header section being sized and arranged such that said conductive element is supportable on said edge and in engagement with said cap and out of contact with said at least one electrode when the conductive element is in said second position and that said conductive element is supported on said edge and received by said depression when the conductive element is in said first position.

13. A tilt switch as recited in claim 12 wherein said substantially ball-shaped element is a globule of electrically conducting metal.

14. A tilt switch as recited in claim 13 wherein said liquid conducting metal contains mercury.

15. A tilt switch as recited in claim 13 wherein the interior surfaces of the header and the cap forming the enclosure are substantially nonwettable by the liquid conducting metal.

16. A tilt switch as recited in claim 12 wherein said substantially ball-shaped conductive element is a solid ball of electrically conductive material.

17. A tilt switch as recited in claim 12 wherein said substantially ball-shaped conductive element is a solid ball of electrically conductive material, and said at least one electrode has a pointed tip portion.

18. A tilt switch as recited in claim 17 wherein said ball, tip portion of said electrode and at least a portion of said ledge containing said edge are coated with metal material having low electrical resistance.

19. A tilt switch as recited in claim 18 wherein the metal coating material includes gold.

20. A tilt switch as recited in claim 12 wherein:

the metal surfaces of the header and cap forming the interior of the enclosure are wetted with an electrically conducting liquid metal material including mercury; and

said ball-shaped conductive element is a solid ball having a surface of a material that is unwettable by said liquid metal material.

21. A tilt switch comprising:

a gravity responsive conductive ball;

housing means defining an enclosure for said gravity responsive conductive ball;

annular ball support means adjacent one end of said housing;

means defining a depression adjacent said one end of said housing surrounded by said annular ball support means;

contact means including at least one switch contact extending through said housing and exposed at said depression and at least one additional switch contact;

said annular ball support means being operable to support said conductive ball in a position where the ball rests against a portion of said housing means projecting beyond said ball support means, with the centroid of said ball located within an imaginery right cylinder having the inner periphery of said annular ball support means as a base; and

said ball being movable in response to the orientation of said switch, to a position unsupported against said portion of said housing means and in contact with both said at least one contact exposed at said depression and said at least one additional switch contact.