Contact structures for sliding switches

• US 6,979,786 B2
• Filed: 03/18/2004
• Issued: 12/27/2005
• Est. Priority Date: 03/18/2004
• Status: Expired due to Fees

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Schoepf, Thomas J, Aukland, Neil R, Drew, George Albert, Rudolph, Gerd
• Primary Examiner(s): Enad, Elvin G.
• Assistant Examiner(s): KLAUS, LISA NHUNG
• Application Number:
  US10/803,764
• Publication Number:
  US 20050205396A1
• Time in Patent Office: 649 Days
• Field of Search: 200/16.A, 200/531, 200547-551, 200 16 R- 16 D, 200/541, 218/6
• US Class Current: 200/16.00A
• CPC Class Codes: H01H 1/403 Contacts forming part of a printed circuit multilayer keyboard switches H01H13/702; thumbwheel switches H01H19/001; for rotary switches with axial contact pressure H01H19/585
• CPC Class Codes: H01H 15/04 Stationary parts; Contacts mounted thereon
• CPC Class Codes: H01H 9/38 Auxiliary contacts on to which the arc is transferred from the main contacts using arcing-horns H01H9/46

Abstract

A contact structure for a sliding switch includes a conductive stationary contact disposed on a base and a conductive movable contact for electrically contacting the stationary contact. The movable contact is movable along a path between a non-contact position and a make-contact position with respect to the stationary contact, and at least one of the contacts has a protruding portion that provides an electrical interface for discharge of arcing as the movable contact breaks from the stationary contact. As a result, the invention prevents or substantially reduces degradation in switch performance which might otherwise be caused by debris accumulation associated with arcing.

Claims

1. A contact structure for a sliding switch, comprising:

first and second conductive stationary contacts of a first potential disposed on a base;

a third conductive stationary contact of a second potential different from said first potential disposed on said base, said third stationary contact including first and second conductive regions; and

a conductive movable contact for electrically contacting at least one of said stationary contacts, said movable contact being movable along a path between a non-contact position and a make contact position with respect to said at least one of said stationary contacts,

said at least one of said stationary contacts having a protruding portion configured to provide an electrical interface for discharge of arcing as said movable contact moves between said make contact position and said non-contact position.

2. A contact structure for a sliding switch as recited in claim 1, wherein said at least one of said stationary contacts is a flat pad.

3. A contact structure for a sliding switch as recited in claim 1, wherein said movable contact is generally substantially shaped as a cylinder.

4. A contact structure for a sliding switch as recited in claim 3, wherein a central axis of said movable contact is perpendicular to said path.

5. A contact structure for a sliding switch, comprising:

first and second conductive stationary contacts of a first potential disposed on a base;

a third conductive stationary contact of a second potential different from said first potential disposed on said base, said third stationary contact including first and second conductive regions;

a conductive movable contact disposed to move relative to said first and second stationary contacts along a path extending from a non-contact position, in which said movable contact is electrically isolated from at least one of said stationary contacts to a make-contact position, in which said movable contact maintains a primary electrical interface with said at least one of said stationary contacts;

a contacting zone defined on said at least one of said stationary contacts that electrically contacts said movable contact when said movable contact is in said make-contact position; and

an arcing zone defined on said at least one of said stationary contacts that terminates electrical contact with said movable contact when said movable contact moves from said make-contact position to said non-contact position or initiates electrical contact with said movable contact when said movable contact moves from said non-contact position to said make-contact position, said arcing zone providing an electrical interface where arcing occurs between said at least one of said stationary contacts and said movable contact,

wherein said at least one of said stationary contacts and said movable contact are mutually shaped and oriented such that when said contacting zone is projected along said path onto said arcing zone, at least a portion of a projection of said contacting zone lies outside said arcing zone, thereby providing a region within said contacting zone which is generally outside of an arcing erosion debris path created by said movable contact as said movable contact moves along said path.

6. A method of preventing degradation in performance of a sliding switch comprising the steps of:

providing first and second conductive stationary contacts of a first potential disposed on a base;

providing a third conductive stationary contact of a second potential different from said first potential disposed on said base, said third stationary contact including first and second conductive regions;

providing a conductive movable contact for electrically contacting at least one of said stationary contacts, said movable contact being movable along a path between a non-contact position and a make contact position with respect to said at least one of said stationary contacts;

and causing arcing to occur outside said path upon engagement or disengagement between said conductive moveable contact and said at least one of said stationary contacts.

7. A method of preventing degradation in performance of a sliding switch comprising the steps of:

providing first and second conductive stationary contacts of a first potential disposed on a base;

providing a third conductive stationary contact of a second potential different from said first potential disposed on said base, said third stationary contact including first and second conductive regions;

providing a conductive movable contact for electrically contacting at least one of said stationary contacts, said movable contact being movable along a path between a make contact position and a non-contact position with respect to said at least one of said stationary contacts; and

providing at least one protrusion on at least one of said contacts to provide an electrical interface for discharge of arcing as said movable contact breaks from said at least one of said stationary contacts, wherein said at least one protrusion is configured to direct said discharge of arcing away from at least a portion of said path.

8. A contact structure for a sliding switch, comprising:

first and second conductive stationary contacts of a first potential disposed on a base;

a third conductive stationary contact of a second potential different from said first potential disposed on said base, said third stationary contact including first and second conductive regions; and

a conductive movable contact for electrically connecting said first and second stationary contacts, said movable contact being movable from a make contact position, in which said movable contact electrically connects said stationary contacts, to a non-contact position, in which said stationary contacts are electrically isolated from one another, said movable contact being configured to simultaneously terminate electrical contact with both of said first and second stationary contacts as said movable contact moves from said make contact position to said non-contact position.

9. A contact structure for a sliding switch, comprising:

first and second conductive stationary contacts of a first polarity disposed on a base;

a conductive third stationary contact of a second polarity opposite said first polarity disposed on said base, said third stationary contact including first and second conductive portions;

an insulator disposed so as to electrically isolate said first, second, and third stationary contacts and said first and second conductive portions of said third stationary contact; and

a conductive movable contact configured to move along a path from a first contact position, in which said movable contact electrically connects said first stationary contact and said first portion of said third stationary contact, to a second contact position, in which said movable contact electrically connects said second stationary contact and said second portion of said third stationary contact,

wherein said path includes a non-contact position located between said first and second contact positions, in which non-contact position said stationary contacts are electrically isolated from one another; and

wherein said movable contact is configured to terminate electrical contact with said first portion of said third stationary contact before said movable contact terminates electrical contact with said first stationary contact as said movable contact moves from said first contact position toward said non-contact positions thereby directing discharge of arcing to said third stationary contact and preventing degradation of insulation performance between said first and second stationary contacts.