Tire pressure indicator system

• US 4,137,520 A
• Filed: 05/12/1978
• Issued: 01/30/1979
• Est. Priority Date: 05/12/1978
• Status: Expired due to Term

• Current Assignee: Devau Levi J.
• Original Assignee: Jay M. Halpert
• Inventors: Deveau, Levi J.
• Primary Examiner(s): Swisher, S. Clement
• Assistant Examiner(s): Corr, Denis E.
• Application Number:
  US05/905,205
• Time in Patent Office: 263 Days
• Field of Search: 73/146.5, 73/146.8, 73/146.4, 73/146.3, 73/146.2, 73/146, 340/58, 340/539, 200/61.22, 200/61.25
• US Class Current: 340/447
• CPC Class Codes: B60C 23/0433 Radio signals

Abstract

A tire pressure is measured by an electrical strain gage and a telemetering transmitter micro chip process and transmitter signal from a motor vehicle tire, indicating an abnormal tire pressure range. The above described tire pressure indicator includes a pressure tight bellows container which is preloaded to a selected gas pressure, and which contains the strain gage, telemetering signal transmitter and a battery power source. The tire pressure indicator is secured and disposed in the tire interior, mounted on the tire air pressure valve stem. A simple signal receiver warns of abnormal tire pressure, receiving the transmitted signal from any tire pressure indicator disposed in a single vehicle tire set.

Claims

1. A vehicular tire pressure indicator system, in combination comprising:

at least one tire pressure indicator having

a diaphragm wire strain gage adapted to signal on departure of said diaphragm from a specified pressure range value,

a signal transmitter disposed on a microchip, said transmitter adaptively coupled to receive an unbalanced pressure electrical signal from said strain gage, and to transmit said pressure signal to a tire stem metal antenna,

a battery power source electrically powering said indicator,

a flexible bellows hermetically enclosing said strain gage, signal transmitter, and said power source, said flexible bellows having an inert gas atmosphere disposed therein at a specific pressure value,

a metal valve stem for a tire, having an electrical insulation exterior, providing a signal transmitter antenna,

a mounting clamp means having an electrical conductive coupling between said transmitter and said antenna, said clamp securing said flexible bellows in the interior of said tire disposed on said tire stem,

at least one signal receiver having signal indicating means secured thereon, providing information that said tire pressure indicator signals a tire pressure value exceeding a predetermined value.

2. In the combination set forth in claim 1, the further modification wherein a said signal indicating means is disposed in a vehicle and has a specific designated coded signal receiver and can receive a coded signal from a specifically designated tire.