OCCUPANT SENSOR SEAT SWITCH

• US 3,859,485 A
• Filed: 02/26/1973
• Issued: 01/07/1975
• Est. Priority Date: 02/26/1973
• Status: Expired due to Term

• Current Assignee: United Technologies Automotive, Inc. (Lear Corporation)
• Original Assignee: Floyd J. Sandi, Paul J. Blinkilde
• Inventors: Blinkilde, Paul J., Sandi, Floyd J.
• Primary Examiner(s): Smith, Jr., David
• Application Number:
  US05/335,786
• Time in Patent Office: 680 Days
• Field of Search: 200/85A,86R,166C 338/114,100 340/278
• US Class Current: 200/85.00A
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: B60N 2/0024 for identifying, categorising or investigation of the occupant or object on the seat
• CPC Class Codes: B60N 2/0033 mounted on or in the foam cushion
• CPC Class Codes: B60N 2/0034 in, under or on the seat cover
• CPC Class Codes: B60N 2/0035 characterised by the sensor data transmission, e.g. wired connections or wireless transmitters therefor; characterised by the sensor data processing, e.g. seat sensor signal amplification or electric circuits for providing seat sensor information
• CPC Class Codes: B60N 2210/46 Electric switches
• CPC Class Codes: B60N 2230/10 Wired data transmission
• CPC Class Codes: H01H 1/029 comprising conducting material dispersed in an elastic support or binding material
• CPC Class Codes: H01H 3/141 Cushion or mat switches

Abstract

A pressure sensitive occupant sensor seat switch to detect the presence of an occupant in an automobile seat. A flat body formed of electrically insulating, resilient compressible material has one or more openings extending therethrough. A pad formed of electrically nonconductive compressible, resilient, inorganic or semiorganic material having discrete electrically conductive particles dispersed throughout occupies each opening. When the pad is uncompressed, the electrically conductive particles do not engage one another. When the pad is compressed, however, the electrically conductive particles engage one another and the pad becomes conductive. Electrical conductors on both sides of the insulating body make electrical contact to the pads so that the switch assembly controls a device connected to it when pressure is applied.

Claims

1. A flexible pressure sensitive switch for sensing the presence of an occupant in a vehicle seat, said switch comprising:

first and second flexible, sheet-like, relatively strong laminates each comprising a film of insulation material having a thin conductive coating on one side;

a flat electrically nonconductive body of resilient compressible foamed material interposed between said first and second laminates, the upper surface of said body being adhesively bonded to the conductive coating of said first laminate and the lower surface of said body being adhesively bonded to the conductive coating of said second laminate, said body having a set of at least two longitudinally spaced openings each extending from said upper surface to said lower surface, each of said openings being open to the respective portions of said conductive coatings overlying said openings;

a resilient compressible contact pad occupying each of said openings in said body, each said contact pad being made of an elastomer with conductive particles dispersed therethrough such that said contact pad is electrically conductive when compressed above a predetermined value and electrically nonconductive when uncompressed, each said contact pad having end portions facing the respective conductive coatings on said laminates for conductive connection therewith so that pressure applied to a localized portion of said first laminate overlying said contact pad will result in compression of said contact pad between the respective conductive coatings of said laminates to provide a bridging conductive path therebetween, said body normally maintaining said laminates in a spaced relation such that each said contact pad is maintained in a substantially uncompressed condition in the absence of pressure applied directly against said localized portion of said first laminate overlying said contact pad; and

means for making external elelctrical connection to said conductive coatings whereby the application of pressure against any of said localized portions of said first laminate overlying said contact pads completes a ciricuit to said external connection means.

2. The switch according to claim 1 wherein:

said body has two sets of said longitudinally spaced openings, one of said sets of openings being laterally spaced from the other of said sets of openings, one each of said openings being occupied by one of said contact pads;

the conductive coating of one of said laminates overlying the contact pads occupying all of said openings and providing a conductive path interconnecting all of said contact pads, the conductive coating of the other of said laminates being in the form of two electrically isolated portions, one of said isolated portions overlying the contact pads occupying said one set of openings and the other of said isolated portions overlying the contact pads occupying said other set of openings;

said external connection means comprising terminal means connected to said isolated portions of conductive coating of said other laminate whereby application of pressure against the localized portions of said first laminate overlying at least one of the contact pads occupying said second set of openings is required to complete a circuit to said external connection means.

3. In combination, a vehicle seat including a pad of foam material having a recessed pocket in one localized area thereof, and a flexible pressure sensitive switch disposed within said recessed pocket for sensing the presence of an occupant on said one localized area of said seat pad, said switch comprising:

first and second flexible, sheet-like, relatively strong laminates each comprising a film of insulation material having a thin conductive coating on one side;

a flat electrically nonconductive body of resilient compressible foamed material interposed between said first and second laminates, the upper surface of said body being adhesively bonded to the conductive coating of said first laminate and the lower Surface of said body being adhesively bonded to the conductive coating of said second laminate, said body having a set of at least two longitudinally spaced openings each extending from said upper surface to said lower surface, each of said openings being open to the respective portions of said conductive coatings overlying said openings;

a resilient compressible contact pad occupying each of said openings in said body, each said contact pad being made of an elastomer with conductive particles dispersed therethrough such that said contact pad is electrically conductive when compressed above a predetermined value and electrically nonconductive when uncompressed, each said contact pad having end portions facing the respective conductive coatings on said laminates for conductive connection therewith so that during seat occupancy pressure applied to a localized portion of said first laminate overlying said contact pad will result in compression of said contact pad between the respective conductive coatings of said laminates to provide a bridging conductive path therebetween;

said body normally maintaining said laminates in a spaced relation such that each said contact pad is maintained in a substantially uncompressed condition in the absence of pressure applied directly against said localized portion of said first laminate overlying said contact pad; and

means for making external electrical connections to said conductive coatings whereby during occupancy of said seat at said one localized area of said seat pad the application of pressure against any of said localized portions of said first laminate overlying said contact pads completes a circuit to said external connection means.

4. The combination of a vehicle seat and a switch assembly according to claim 3 wherein:

said body has two sets of said longitudinally spaced openings, one of said sets of openings being laterally spaced from the other of said sets of openings, one each of said openings being occupied by one of said contact pads;

the conductive coating of one of said laminates overlying the contact pads occupying all of said openings and providing a conductive path interconnecting all of said contact pads, the conductive coating of the other of said laminates being in the form of two electrically isolated portions, one of said isolated portions overlying the contact pads occupying said one set of openings and the other of said isolated portions overlying the contact pads occupying said other set of openings;

said external connection means comprising terminal means connected to said isolated portions of the conductive coating of said other laminate whereby application of pressure against the localized portions of said first laminate overlying at least one of the contact pads occupying said first set of openings and at least one of the contact pads occupying said second set of openings is required to complete a circuit to said external connection means.