Tire pneumatic pressure detector

• US 6,720,869 B2
• Filed: 12/20/2001
• Issued: 04/13/2004
• Est. Priority Date: 01/10/2001
• Status: Active Grant

• Current Assignee: DENSO Corporation, Daihatsu Motor Company Limited (Toyota Motor Corporation)
• Original Assignee: DENSO Corporation, Daihatsu Motor Company Limited (Toyota Motor Corporation)
• Inventors: Tanaka, Osamu, Makino, Nobuhiko, Hatoh, Takeshi, Matsuki, Takumo, Watanabe, Takashi, Taguchi, Takeyasu
• Primary Examiner(s): TONG, NINA C
• Application Number:
  US10/022,223
• Publication Number:
  US 20020089417A1
• Time in Patent Office: 845 Days
• Field of Search: 340/442, 340/443, 340/444, 340/445, 340/446, 340/447, 340/448, 731/465, 731/46, 731/462
• US Class Current: 340/442
• CPC Class Codes: B60C 23/0401 characterised by the type of alarm
• CPC Class Codes: B60C 23/061 by monitoring wheel speed measuring distance traversed on the ground by vehicles G01C22/00

Abstract

A tire pneumatic pressure detector includes a tire pneumatic pressure detection unit, a first memory storing data associated with a timing at which the drop of tire pneumatic pressure occurs, a second memory storing second data including one or more of a lapse of time from which the tire pneumatic pressure drop occurs, and third data associated with running distance from the timing when a fault diagnosis signal is input.

Claims

1. A tire pneumatic pressure detector comprising:

tire pneumatic pressure detection means for detecting a tire pneumatic pressure;

pneumatic pressure drop detection means for comparing the tire pneumatic pressure detected by said tire pneumatic pressure detection means with a predetermined value, and detecting a drop of the tire pneumatic pressure when the tire pneumatic pressure is tower than the predetermined value;

first memory means for storing first data associated with a timing of the drop of the tire pneumatic pressure;

second memory means for storing second data including one or more of;

a lapse of time from said first data, and third data associated with a running distance from a point associated with said first data; and

switching number detection means for detecting a number of switching times of an ignition switch;

wherein, when the number of switching times detected by said switching number detection means is greater than a predetermined number of times when said tire pneumatic pressure drop detection means detects that the tire pneumatic pressure is higher than said predetermined value, the second data stored in said second memory means is cleared.

2. A tire pneumatic pressure detector according to claim 1, further comprising an alarm for providing a warning when the drop of the tire pneumatic pressure occurs;

wherein said alarm changes a warning method in accordance with the second data.

3. A tire pneumatic pressure detector according to claim 2, wherein said alarm further includes an alarm lamp having a flashing frequency when said warning is being provided, and wherein said flashing frequency is changed in proportion to the second data.

4. A tire pneumatic pressure detector comprising:

tire pneumatic pressure detection means for detecting a tire pneumatic pressure;

pneumatic pressure drop detection means for comparing the tire pneumatic pressure detected by said tire pneumatic pressure detection means with a predetermined value, and detecting a drop of the tire pneumatic pressure when the tire pneumatic pressure is lower than the predetermined value;

first memory means for storing first data associated with a timing of the drop of the tire pneumatic pressure; and

second memory means for storing second data including one or more of;

a lapse of time from said fist data, and third data associated with a running distance from a point associated with said first data;

wherein, the second data is output to a fault-diagnosing device when the fault-diagnosing device inputs a fault diagnosis signal.

5. A tire pneumatic pressure detector according to claim 4, further comprising an alarm for providing a warning when the drop of the tire pneumatic pressure occurs;

wherein said alarm changes said warning in accordance with the second data.

6. A tire pneumatic pressure detector according to claim 5, wherein said alarm further includes an alarm lamp having a flashing frequency when said warning is being provided, and wherein said flashing frequency is changed in proportion to the second data.