Tire pressure monitoring system

• US 7,224,267 B1
• Filed: 05/28/2004
• Issued: 05/29/2007
• Est. Priority Date: 05/28/2004
• Status: Expired due to Fees

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Ellis, Nathaniel
• Primary Examiner(s): GOINS, DAVETTA WOODS
• Application Number:
  US10/856,677
• Time in Patent Office: 1,096 Days
• Field of Search: 340/442, 340/438, 340/447, 340/449, 340/445, 731/465, 73/350.2, 123/1.A
• US Class Current: 340/442
• CPC Class Codes: B60C 23/0408 transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver

Abstract

A system and method for monitoring tire pressure in a tire of a vehicle is described, in which a tire pressure reading in the tire and an ambient pressure reading are received, and a warning indicator visible to an operator of a vehicle is selectively activated based on the tire pressure reading, the ambient pressure reading, and a predetermined threshold. In one embodiment, the ambient pressure is used by an engine control system for regulating the air-fuel intake, transmitted to a communications bus, and used by a tire pressure monitoring subsystem configured for receiving the ambient pressure reading from the communications bus.

Claims

1. A method of monitoring tire pressure in a tire of a vehicle, comprising:

receiving input indicative of a tire pressure reading in the tire;

receiving input indicative of an ambient pressure;

comparing a difference of the tire pressure reading and the ambient pressure reading with a predetermined threshold;

if the difference is less than the predetermined threshold, then activating a warning indicator visible to an operator of the vehicle.

2. A method according to claim 1, wherein said receiving the input indicative of the ambient pressure includes receiving the input from an engine control subsystem configured for managing fuel intake.

3. A method according to claim 2, wherein said receiving the input indicative of the ambient pressure includes:

receiving a packet broadcast to a serial data communications bus; and

checking the packet to determine whether content of the packet is indicative of the ambient pressure.

4. A method according to claim 1, wherein said receiving indicative of the tire pressure reading in the tire includes receiving the input from a sensor disposed within the tire.

5. A method of monitoring tire pressure in a tire of a vehicle, comprising:

receiving input indicative of a tire pressure reading in the tire;

receiving input indicative of an ambient pressure;

comparing the tire pressure reading with a sum of the ambient pressure reading and a predetermined threshold;

if the tire pressure reading is less than the sum, then activating a warning indicator visible to an operator of the vehicle.

6. A method according to claim 5, wherein said receiving the input indicative of the ambient pressure includes receiving the input from an engine control subsystem configured for managing air fuel intake.

7. A method according to claim 6, wherein said receiving the input indicative of the ambient pressure includes:

receiving a packet broadcast to a serial data communications bus; and

checking the packet to determine whether content of the packet is indicative of the ambient pressure.

8. A method according to claim 5, wherein said receiving indicative of the tire pressure reading in the tire includes receiving the input from a sensor disposed within the tire.

9. An automotive system comprising:

a communications bus;

a tire pressure sensor disposed within a tire for measuring a tire pressure;

an ambient pressure sensor for measuring an ambient pressure;

an engine control system for regulating air fuel intake based on the ambient pressure and transmitting an indication of the ambient pressure to the communications bus; and

a tire pressure monitoring system configured for;

receiving input indicative of the tire pressure from the tire pressure sensor,

receiving the indication of the ambient pressure from the communications bus; and

selectively activating a warning indicator visible to an operator of a vehicle based on the tire pressure, the ambient pressure, and a predetermined threshold.

10. An automotive system according to claim 9, wherein the tire pressure system is configured for:

comparing a difference of the tire pressure and the ambient pressure with the predetermined threshold;

if the difference is less than the predetermined threshold, then activating the warning indicator.

11. An automotive system according to claim 9, wherein the tire pressure system is configured for:

comparing the tire pressure with a sum of the ambient pressure and a predetermined threshold;

if the tire pressure reading is less than the sum, then activating the warning indicator.

12. An automotive system according to claim 9, wherein the tire pressure system is configured for:

receiving a packet broadcast to a serial data communications bus; and

checking the packet to determine whether content of the packet is indicative of the ambient pressure.

13. A computer-readable medium bearing instructions for operating an tire pressure sensor system, said instructions being arranged, upon execution thereof, to cause one or more processors to perform the steps of:

receiving input indicative of tire pressure from a tire pressure sensor,

receiving an indication of the ambient pressure from a communications bus; and

selectively activating a warning indicator visible to an operator of a vehicle based on the tire pressure, the ambient pressure, and a predetermined threshold.

14. A computer-readable medium according to claim 13, wherein said selectively activating includes:

comparing a difference of the tire pressure and the ambient pressure with the predetermined threshold;

if the difference is less than the predetermined threshold, then activating the warning indicator.

15. A computer-readable medium according to claim 13, wherein said selectively activating includes:

comparing the tire pressure with a sum of the ambient pressure and a predetermined threshold;

if the tire pressure reading is less than the sum, then activating the warning indicator.

16. A computer-readable medium according to claim 13, wherein said selectively activating includes:

receiving a packet broadcast to a serial data communications bus; and

checking the packet to determine whether content of the packet is indicative of the ambient pressure.

17. An automotive system according to claim 13, wherein the ambient pressure was measured within a predetermined number of vehicle speed pulses since ignition and used for monitoring tire pressure after at least twice the predetermined number of vehicle speed pulses.

18. A computer-readable medium bearing instructions for operating an engine control system, said instructions being arranged, upon execution thereof, to cause one or more processors to perform the steps of:

reading an ambient pressure value from a pressure sensor;

controlling a mixture of fuel and an oxidant based on the ambient pressure value; and

transmitting the ambient pressure value to a communications bus.

19. A computer-readable medium according to claim 18, wherein said transmitting the ambient pressure value to the communications bus includes sending a packet indicating content of ambient pressure.

20. A method for upgrading a tire pressure monitoring system of a vehicle comprising:

installing first instructions in a computer-readable medium accessible to an engine control system, said first instructions being arranged, upon execution thereof, to cause one or more processors to transmit an indication of ambient pressure to a communications bus; and

installing second instructions in a computer-readable medium accessible to an engine control system, said second instructions being arranged, upon execution thereof, to cause one or more processors to perform the steps of;

receiving the indication of the ambient pressure from a communications bus; and

selectively activating a warning indicator visible to an operator of a vehicle based on a tire pressure of a tire, the ambient pressure, and a predetermined threshold.