Vehicle with brake force regulations on gradient

• US 5,957,552 A
• Filed: 09/17/1997
• Issued: 09/28/1999
• Est. Priority Date: 09/13/1996
• Status: Expired due to Term

• Current Assignee: Wabco GmbH (Wabco Holdings Incorporated)
• Original Assignee: Wabco GmbH (Wabco Holdings Incorporated)
• Inventors: Claussen, Heiko, Eickhoff, Jurgen
• Primary Examiner(s): Graham, Matthew C.
• Application Number:
  US08/932,260
• Time in Patent Office: 741 Days
• Field of Search: 303/186, 303/113.5, 303/192, 303/9.62-9.76
• US Class Current: 303/192
• CPC Class Codes: B60T 2201/04 Hill descent control
• CPC Class Codes: B60T 7/12 for automatic initiation; for initiation not subject to will of driver or passenger limiting speed of vehicles other than rail vehicles B60K31/00
• CPC Class Codes: B60T 7/126 Brakes for railway vehicles coming into operation in case of exceeding a predetermined speed self-acting brakes in general F16D59/00
• CPC Class Codes: B60T 8/1766 Proportioning of brake forces according to vehicle axle loads, e.g. front to rear of vehicle
• CPC Class Codes: B60T 8/245 Longitudinal vehicle inclination
• CPC Class Codes: B60T 8/26 characterised by producing differential braking between front and rear wheels using electrical circuitry or regulation means B60T8/17
• CPC Class Codes: B60T 8/86 wherein the brakes are automatically applied in accordance with a speed condition and having means for overriding the automatic braking device when a skid condition occurs

Abstract

A process is disclosed for adjusting the speed of a vehicle travelling on a gradient to a predetermined desired speed, wherein the vehicle is equipped with an ABS and/or ASR system, comprises determining the actual speed of the vehicle travelling on a gradient, determining a control deviation for the vehicle, the control deviation being the difference between the actual speed of the vehicle and the desired speed, and actively applying the brakes of the vehicle when the control deviation is greater than a predetermined amount. Only the brakes of the downhill axle are braked so long as the control deviation is less than a predetermined control deviation, or so long as the slip of the braked wheels are less than a predetermined slip. The brakes of the uphill axle are applied only if the predetermined control deviation is exceeded.

Claims

1. A process for adjusting the speed of a vehicle travelling on a gradient to a predetermined desired speed, wherein said vehicle is equipped with an ABS or ASR system, comprising

determining the actual speed at which said vehicle is traveling on said gradient,

determining a control deviation for said vehicle, said control deviation being the difference between said actual speed of said vehicle and said desired speed,

actively applying the brakes of said vehicle when the control deviation is greater than a predetermined amount,

wherein only the brakes of the wheels located on the downhill axle of said vehicle are braked so long as said control deviation is less than a predetermined control deviation, or so long as the slip of the braked wheels is less than a predetermined slip.

2. The process of claim 1 wherein said predetermined control deviation is approximately 0 to 2 km/h.

3. The process of claim 1 wherein said predetermined slip is approximately 0 to 5%.

4. The process of claim 1 wherein a control deviation of ±

0.5 km/h is assigned to the wheels on the downhill axle, and a control deviation of ±

0.7 km/h is assigned to the wheels on the uphill axle, said wheels on the downhill and on the uphill axles being braked only when their respective control deviations are exceeded.

5. The process of claim 1, further comprising monitoring the temperature of at least the brakes on the downhill axle and emitting a warning signal when the temperature exceeds a fixed limit.

6. A process for adjusting the speed of a vehicle travelling on a gradient to a predetermined desired speed, wherein said vehicle is equipped with an ABS or an ASR system, comprising

determining the actual speed at which said vehicle is travelling on the gradient,

determining a control deviation for said vehicle, said control deviation being the difference between said actual speed of said vehicle and said desired speed,

actively applying the brakes of said vehicle when the control deviation is greater than a predetermined amount,

distributing the brake force during said active brake application so that the brake force applied to the brakes on the downhill axle is greater than the brake force applied to the brakes of the uphill axle by a fixed percentage, and

monitoring the temperature of at least the brakes of the downhill axle and emitting a warning signal when the temperature exceeds a fixed limit.

7. The process of claim 6 wherein the ratio of brake forces applied to the downhill axle and to the uphill axle is about 70% to 30%.