Apparatus for repeatable adjustment of tire pressure

• US 5,540,268 A
• Filed: 05/04/1994
• Issued: 07/30/1996
• Est. Priority Date: 12/17/1991
• Status: Expired due to Term

• Current Assignee: CM Automotive Systems, Inc.
• Original Assignee: CM Automotive Systems, Inc.
• Inventors: Mittal, Chander
• Primary Examiner(s): Knable, Geoffrey L.
• Assistant Examiner(s): Lorin, Francis J.
• Application Number:
  US08/238,251
• Time in Patent Office: 818 Days
• Field of Search: 152/415, 152/416, 152/417, 141/4, 141/38, 141/95, 141/195, 141/197
• US Class Current: 152/415
• CPC Class Codes: B60C 23/00318 on the wheels or the hubs
• CPC Class Codes: B60C 23/00354 Details of valves
• CPC Class Codes: B60C 23/00363 Details of sealings
• CPC Class Codes: B60C 23/00372 characterised by fluid diagrams
• CPC Class Codes: Y10T 137/3615 Pulsating

Abstract

An apparatus for adjusting and controlling air pressure in pneumatic vehicle tires. The apparatus, which is microcomputer based, automatically checks tire pressure, checks for tire and system leaks and controllably inflates and deflates the tires as conditions warrant. The apparatus also includes unique tire inflation valves which are designed to accommodate high levels of particulate contamination within the system.

Claims

1. An apparatus operable in atmosphere for adjusting the air pressure within the pneumatic tires of a vehicle having a plurality of tires, comprising:

(a) a source of air under pressure;

(b) a manifold having an inlet in communication with said source of air under pressure, a first outlet in communication with the pneumatic tires and a second outlet in communication with atmosphere;

(c) first valve means disposed between said inlet of said manifold and to said source of air under pressure for controlling air flow between said source of air under pressure and said manifold;

(d) second valve means disposed between said manifold and at least one of the pneumatic tires for controlling air flow between said manifold and the pneumatic tire, said second valve means comprising;

(i) a valve body having a valve seat and first and second chambers;

(ii) a piston reciprocally movable within said valve body relative to said first and second chambers;

(iii) a poppet movable relative to said piston within said first chamber both longitudinally and laterally relative to said valve seat in a wobbling action; and

(iv) a resiliently deformable diaphragm connected to said valve body and to said piston for movement with said piston;

(e) third valve means disposed between said manifold and said second outlet for controlling air flow between said manifold and atmosphere;

(f) transducer means for measuring the pressure within said manifold and for generating a signal corresponding to the measured pressure, said manifold being in fluid communication with said first, second and third valve means and with said transducer means; and

(g) control means connected to said transducer means, and to said first and third valves for receiving said signals generated by said transducer means and for operating said first and third valves in response to said signals in a manner such that said first valve is modulated so as to cause discrete pulses of air under pressure to be controllably directed toward said second valve means.

2. An apparatus operable in atmosphere for adjusting the air pressure within the pneumatic tires of a vehicle having a plurality of tires, comprising:

(a) a source of air under pressure;

(b) a manifold having an inlet in communication with said source of air under pressure, a first outlet in communication with the pneumatic tires and a second outlet in communication with atmosphere;

(c) first valve means disposed between said inlet of said manifold and to said source of air under pressure for controlling air flow between said source of air under pressure and said manifold;

(d) second valve means disposed between said manifold and at least one of the pneumatic tires for controlling air flow between said manifold and the pneumatic tire, said second valve means comprising;

(i) a valve body having a valve seat and first and second chambers;

(ii) a piston reciprocally movable within said valve body relative to said first and second chambers and sealably movable between the second chamber and the atmosphere and said piston being guided through a narrow bore forming a non-resilient and low-leakage seal;

(iii) a poppet movable relative to said piston within said first chamber both longitudinally and laterally relative to said valve seat in a wobbling action;

(iv) a resiliently deformable diaphragm connected to said valve body and to said piston for movement with said piston; and

(v) a pilot passage of tortuous design connecting the second chamber and the pilot chamber formed between the valve body and the deformable diaphragm;

(e) third valve means of a first flow capacity disposed between said manifold and said second outlet for controlling air flow between said manifold and atmosphere;

(f) fourth valve means of a second flow capacity, said fourth valve means being disposed between said manifold and said second outlet for controlling air flow between said manifold and atmosphere, said second flow capacity being larger than said first flow capacity;

(g) transducer means for measuring the pressure within said manifold and for generating a signal corresponding to the measured pressure, said manifold being in fluid communication with said first, second and third valve means and with said transducer means; and

(h) control means connected to said transducer means, and to said first, third and fourth valves for receiving said signals generated by said transducer means and for operating said first, third and fourth valves in response to said signals in a manner such that said first valve is modulated so as to cause discrete pulses of air under pressure to be controllably directed toward said second valve means.