Pressure sensitive switch

• US 5,965,856 A
• Filed: 11/28/1997
• Issued: 10/12/1999
• Est. Priority Date: 11/28/1996
• Status: Expired due to Term

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Okada, Shoji, Tanaka, Kazuya, Takayanagi, Hitoshi, Oka, Toshimitsu, Fujie, Naofumi
• Primary Examiner(s): Scott, J. R.
• Application Number:
  US08/979,714
• Time in Patent Office: 683 Days
• Field of Search: 200/5 A, 200/85 R, 200/85 A, 200/512-517, 428/209
• 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 2/003 characterised by the sensor mounting location in or on the seat
• CPC Class Codes: B60N 2210/46 Electric switches
• CPC Class Codes: B60R 21/01516 using force or pressure sensing means
• CPC Class Codes: H01H 3/141 Cushion or mat switches

Abstract

A sheet-like pressure sensitive switch is disclosed. A spacer 2 of an insulating material is interposed between a first film 1 of an insulating material which is provided with a first electrode 1a and a second film 3 of an insulating material which is provided with a second electrode 3a. The spacer 2 has a number of openings 2a, through which the first electrode 1a and the second electrode 3a oppose each other with an air gap therebetween. A first lead wire 4a and a second lead wire 4b are connected to the first electrode 1a and the second electrode 3a, respectively. In a pressure sensitive switch according to a first embodiment, the first and the second film 1, 3 are formed of polyethylene naphthalate films. In a pressure sensitive switch according to a second embodiment, the second film 3 is formed of polyethylene terephthalate film while the first film 1 is formed of polyethylene naphthalate film.

Claims

1. A pressure sensitive seating switch adapted to be internally housed in a vehicle seat comprising:

a first flat resilient film of an insulating material carrying a flat conductive layer on its flat reverse surface;

a spacer of an insulating material having an opening of an increased area as compared with the thickness thereof and extending through the spacer in the direction of thickness, the spacer having one of its front and reverse surfaces jointed to the reverse surface of the first film;

a second flat resilient film of an insulating material carrying a flat conductive layer on its reverse surface, which is joined to the other of the front and the reverse surface of the spacer; and

a first and a second lead wire connected to the conductive layers on the first and the second films, respectively;

wherein at least one of the first and the second films is formed of polyethylene naphthalate and a ratio of the size of the opening to the spacer thickness is chosen for flexing the films to bring the conductive layers into contact with each other by a force which is greater than a given value while both films are maintained apart due to the resilience of the films to keep the conductive layers spaced from each other when a force is below the given value.

2. A pressure sensitive switch according to claim 3, in which one of the first and the second films is formed of polyethylene naphthalate film while the other is formed of polyethylene terephthalate film.