Method for alarming of tire deflation and apparatus therefor

• US 5,691,694 A
• Filed: 09/22/1995
• Issued: 11/25/1997
• Est. Priority Date: 09/27/1994
• Status: Expired due to Term

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation), Sumitomo Rubber Industries Limited
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation), Sumitomo Rubber Industries Limited
• Inventors: Horie, Hiroto
• Primary Examiner(s): Swarthout, Brent A.
• Assistant Examiner(s): TRIEU, VAN THANH
• Application Number:
  US08/531,898
• Time in Patent Office: 795 Days
• Field of Search: 340/442, 340/443, 340/444, 340/447, 340/457, 340/457.4, 340/309.15, 340/636, 340/669, 340/438, 340/425.5, 73/146, 73/146.2, 73/146.5, 116/34 R
• US Class Current: 340/442
• CPC Class Codes: B60C 23/00 Devices for measuring, signalling, controlling, or distributing tyre pressure or temperature, specially adapted for mounting on vehicles; Arrangement of tyre inflating devices on vehicles, e.g. of pumps or of tanks; Tyre cooling arrangements

Abstract

A tire deflation alarm apparatus to be provided on a vehicle with air-filled tires, comprising: a timer for measuring a period of time from when the air pressure of a tire is set to a normal value to the time when the air pressure spontaneously drops to a dangerous value, the period of time being established beforehand; an alarm portion connected to the timer and designed to give an alarm after the period of time has elapsed; and a reset switch for resetting the timer to the zero hour. The apparatus is capable of warning the tire'"'"'s spontaneous air pressure drop that inevitably occurs when allowed to stand.

Claims

1. A tire deflation alarm apparatus adapted to be provided on a vehicle which utilizes air-filled tires, comprising:

a timer for measuring a period of time from when the air pressure of the tire has been set to a normal value to the time when the air pressure spontaneously drops to a dangerous value, the period of time being established beforehand;

an alarm means connected to the timer and designed to give an alarm after the period of time has elapsed;

a reset switch for resetting the timer to the zero hour; and

a backup battery and charging circuit connected to the timer so that the period of time can be measured when the power is cut off, by means of the backup battery and the charging circuit.

2. The apparatus of claim 1, wherein the period of time measured by the timer is 6 months.

3. The apparatus of claim 1, wherein the period of time measured by the timer is 6 months.

4. A method for measuring the deflation of a vehicle tire and providing a warning of said deflation which comprises:

measuring the period of time from when the air pressure of a tire drops from a normal value to a dangerously low value, said period of time being predetermined;

signaling an alarm when said period of time has elapsed;

providing a backup battery and charging circuit for measuring the time period when the power is cut off; and

resetting the time period to zero.