Brake adjustment method and apparatus thereof

• US 6,755,487 B2
• Filed: 12/05/2001
• Issued: 06/29/2004
• Est. Priority Date: 12/14/2000
• Status: Expired due to Term

• Current Assignee: Komatsu Ltd.
• Original Assignee: Komatsu Ltd.
• Inventors: Yamamoto, Shigeru, Nakagawa, Tomohiro, Suzuki, Kazuyuki
• Primary Examiner(s): Schwartz, Christopher P.
• Assistant Examiner(s): KRAMER, DEVON C
• Application Number:
  US10/002,184
• Publication Number:
  US 20020074856A1
• Time in Patent Office: 937 Days
• Field of Search: 303/121, 180/9.44, 180/9.1, 180/6.7, 701/83
• US Class Current: 303/121
• CPC Class Codes: B60K 2360/682 Arrangements to cover or hide instruments
• CPC Class Codes: B60T 13/22 Brakes applied by springs or weights and released hydraulically
• CPC Class Codes: B62D 11/08 using brakes or clutches as main steering-effecting means
• CPC Class Codes: B62D 11/183 Control systems therefor
• CPC Class Codes: E02F 9/225 Control of steering, e.g. for hydraulic motors driving the vehicle tracks steering in general B62D
• CPC Class Codes: E02F 9/26 Indicating devices E02F5/145 takes precedence

Abstract

A brake adjustment method and apparatus thereof are described which are capable of providing proper brake hydraulic pressure compensation without causing variations due to different adjusters and without lifting the vehicle. The apparatus comprises: (a) an adjustment mode setting device for setting an adjustment mode for adjusting brake hydraulic pressure to a proper value, while the vehicle is in its stopped state; (b) brake hydraulic pressure changing control for controlling the brake hydraulic pressure to gradually change when the adjustment mode has been set by the adjustment mode setting device; (c) vehicle travel start detector for detecting a start of traveling of the vehicle; (d) brake pressure command value detector for detecting a brake pressure command value at the start of traveling of the vehicle, if a start of vehicle traveling is detected by the vehicle travel start detector while the brake hydraulic pressure is gradually changed by the brake hydraulic pressure changing control; and (e) a brake hydraulic pressure correcting system for correcting the brake hydraulic pressure to a proper value, based on the brake pressure command value detected by the brake pressure command value detector.

Claims

1. A brake adjustment method adapted for use with a tracklaying vehicle wherein right and left drive wheels are each provided with a clutch and a brake and wherein clutch hydraulic pressure and brake hydraulic pressure are controlled by operation of an electrical power-assisted steering lever to allow a right or left turn of the vehicle, the method comprising the steps of:

selecting an adjustment mode with the vehicle in its stopped state and with a crawler belt of the vehicle in contact with the ground;

detecting a command value for the brake hydraulic pressure at the start of vehicle traveling with the crawler belt in contact with the ground while the brake hydraulic pressure is gradually changed; and

adjusting a brake based on the detected command value while the crawler belt remains in contact with the ground.

2. A brake adjustment apparatus adapted for use with a tracklaying vehicle wherein right and left drive wheels are each provided with a clutch and a brake and wherein clutch hydraulic pressure and brake hydraulic pressure are controlled by operation of an electrical power-assisted steering lever to allow a right or left turn of the vehicle, the apparatus comprising:

(a) adjustment mode setting means for setting an adjustment mode for adjusting the brake hydraulic pressure to a proper value, while the vehicle being in its stopped state;

(b) brake hydraulic pressure changing means for controlling the brake hydraulic pressure to gradually change when the adjustment mode has been set by the adjustment mode setting means;

(c) vehicle travel start detecting means for detecting a start of traveling of the vehicle;

(d) brake pressure command value detecting means for detecting a brake pressure command value at the start of traveling of the vehicle, if a start of vehicle traveling is detected by the vehicle travel start detecting means while the brake hydraulic pressure being gradually changed by the brake hydraulic pressure changing means; and

(e) brake hydraulic pressure correcting means for correcting the brake hydraulic pressure to a proper value, based on the brake pressure command value detected by the brake pressure command value detecting means.

3. A brake adjustment apparatus according to claim 2,

wherein the brake hydraulic pressure correcting means corrects the brake hydraulic pressure based on the difference between a reference brake pressure command value corresponding to a specified tractive force of the vehicle and the brake pressure command value detected by the brake pressure command value detecting means.

4. A brake adjustment apparatus according to claim 2,

wherein the adjustment mode setting means can set the adjustment mode with at least one of the clutches, which is located on an adjusted side, being in its engaged condition at all times, and

wherein a transmission output-side rotation sensor for detecting the rotation of the output side of a transmission of the vehicle is used as the vehicle travel start detecting means.

5. A brake adjustment apparatus according to claim 4,

wherein the brake hydraulic pressure correcting means corrects the brake hydraulic pressure based on the difference between a reference brake pressure command value corresponding to a specified tractive force of the vehicle and the brake pressure command value detected by the brake pressure command value detecting means.

6. A brake adjustment apparatus according to claim 2,

wherein the brake hydraulic pressure changing means sets an initial value for the brake hydraulic pressure in accordance with a reference line representing reference brake pressure command values relative to the tractive force of the vehicle, the initial value being used as a basis for changing the brake hydraulic pressure.

7. A brake adjustment apparatus according to claim 6,

wherein the brake hydraulic pressure correcting means corrects the brake hydraulic pressure based on the difference between a reference brake pressure command value corresponding to a specified tractive force of the vehicle and the brake pressure command value detected by the brake pressure command value detecting means.

8. A brake adjustment apparatus according to claim 6,

wherein the brake hydraulic pressure changing means controls the brake hydraulic pressure so as to increase step-wise by a specified amount at specified time intervals, starting from said initial value.

9. A brake adjustment apparatus according to claim 8,

wherein the brake hydraulic pressure correcting means corrects the brake hydraulic pressure based on the difference between a reference brake pressure command value corresponding to a specified tractive force of the vehicle and the brake pressure command value detected by the brake pressure command value detecting means.