WHEEL DIAMETER VARIATION-DETECTING DEVICE

• US 20100114428A1
• Filed: 05/12/2008
• Published: 05/06/2010
• Est. Priority Date: 06/01/2007
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Kurata, Takeshi, Eguchi, Takahiro, Totsuka, Hirohiko, Fujimoto, Shuichi
• Granted Patent: US 9,008,903 B2
• Time in Patent Office: Days
• US Class Current: 701/36
• CPC Class Codes: B60T 2240/08 Spare wheel detection; Adjusting brake control in case of spare wheel use
• CPC Class Codes: B60W 40/1005 Driving resistance
• CPC Class Codes: B60W 40/105 Speed
• CPC Class Codes: G01M 17/013 Wheels
• CPC Class Codes: G01M 17/02 Tyres

Abstract

There is provided a wheel diameter variation-detecting device which is capable of properly detecting relative variation in diameter between a plurality of wheels of a vehicle. The wheel diameter variation-detecting device 1 for detecting variation in diameter between a plurality of wheels WFL, WFR, WRL, WRR of a vehicle V which rotate independently of each other detects rotational speeds NFL, NFR, NRL, NRR of the respective wheels WFL, WFR, WRL, WRR, and calculates a variation parameter RDR indicative of variation in diameter between the wheels WFL, WFR, WRL, WRR, using one of the wheels WFL, WFR, WRL, WRR as a reference wheel WRL, based on a result of comparison between the rotational speed NRL, NRR of the reference wheel and that of one of the wheels other than the reference wheel (step 3). Further, the wheel diameter variation-detecting device learns the variation parameter based on a value obtained by averaging a plurality of values of the variation parameter RDR obtained before the detected travelled distance DISSUM reaches a predetermined distance DIS2 (steps 4, 31 to 33, 36, 44).

Claims

1. A wheel diameter variation-detecting device for detecting variation in diameter between a plurality of wheels of a vehicle, the wheels rotating independently of each other, comprising:

wheel rotational speed sensors that detect rotational speeds of the wheels, respectively;

variation parameter-calculating means for calculating a variation parameter indicative of variation in diameter between the wheels, using one of the wheels as a reference wheel, based on a result of comparison between a detected rotational speed of the reference wheel and a detected rotational speed of another wheel;

travelled distance-detecting means for detecting a travelled distance of the vehicle; and

variation parameter-learning means for learning the variation parameter based on a value obtained by averaging a plurality of values of the variation parameter obtained before the detected travelled distance reaches a predetermined distance.

2. A wheel diameter variation-detecting device as claimed in claim 1, wherein the variation parameter represents a ratio between the rotational speed of the reference wheel and the rotational speed of the another wheel.

3. A wheel diameter variation-detecting device as claimed in claim 1 or 2, wherein the wheels include left and right wheels, and

wherein the reference wheel is one of the left and right wheels and the another wheel is the other of the left and right wheels.

4. A wheel diameter variation-detecting device as claimed in claim 1, further comprising storage means for storing a learned value of the variation parameter, learned by said variation parameter-learning means, and

wherein said variation parameter-learning means calculates a provisional learned value of the variation parameter, and determines reliability of the provisional learned value and reliability of the stored learned value based on a result of comparison between the calculated provisional learned value and the learned value stored by said storage means.