Anti-spin control system

• US 4,042,059 A
• Filed: 07/14/1975
• Issued: 08/16/1977
• Est. Priority Date: 05/21/1973
• Status: Expired due to Term

• Current Assignee: Kelsey-Hayes Co. (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: Kelsey-Hayes Co. (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Bertolasi, Robert B.
• Primary Examiner(s): Silverstrim, John P.
• Application Number:
  US05/595,566
• Time in Patent Office: 764 Days
• Field of Search: 180/82 R, 180/103 R, 180/105 R, 180/105 E, 180/44 R, 180/76, 303/100, 303/99, 303/95, 303/96, 303/97, 303/98, 303/99
• US Class Current: 180/271
• CPC Class Codes: B60T 2210/16 Off-road driving conditions
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: B60T 8/175 Brake regulation specially adapted to prevent excessive wheel spin during vehicle acceleration, e.g. for traction control safety devices for propulsion unit control responsive to, or preventing, skidding of wheels B60K28/16
• CPC Class Codes: B60T 8/17613 based on analogue circuits or digital circuits comprised of discrete electronic elements

Abstract

An anti-spin control system for wheeled vehicles having an improved steering angle compensating unit which is preferably in the form of a potentiometer having a resistive element with opposite end terminals connected to a reference potential and an intermediate terminal which is connected to receive the wheel speed signal from its respective wheel speed sensor and which is asymetrically disposed with respect to the end terminals. The potentiometer additionally has a wiping arm which is associated with a vehicle steering member so as to be movable therewith across the resistive element so as to provide a potential at the wiper arm which is determined in accordance with the position of the vehicle steering member and the asymmetrical location of the intermediate terminal. An adjusted wheel speed signal is thus provided at the wiper arm of the potentiometer which initially increases and then decreases in accordance with the position of the steering element for turns in one direction. In this manner, the speed signals of the steerable wheels of the vehicle are compensated for changes in turning radius due to changes in steering angle. Alternative embodiments which utilize the steering angle compensation unit to adjust other signals in the circuit to accomplish the same result are also disclosed.

Claims

1. A spin control system for a steerable vehicle having first and second wheels which are driven at least under predetermined conditions and are steerable through varying angles of steering and which are disposed on laterally opposed sides of said vehicle so that an inside one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels comprising:

means for generating a signal representative of the speed of said inside wheel;

means for generating a reference signal;

compensating means for adjusting the value of said wheel speed signal in accordance with the steering angle of said inside steerable wheel so that, absent a spin condition at said inside steerable wheel, the output of said compensating means at the 0°

steering angle position defines a first signal value and for turns in said one direction from a straight course, the value of the output signal from said compensating means is greater than said first signal value when the turning radius of said inside steerable wheel is less than the average turning radius of said vehicle, is equal to said first signal value when the turning radius of said inside steerable wheel is equal to the average turning radius of said vehicle, and is less than said first signal value when the turning radius of said inside steerable wheel is greater than the average turning radius of said vehicle; and

means for comparing said adjusted wheel speed signal and said reference signal for providing a spin signal.

2. A spin control system according to claim 1 wherein said compensating means includes a potentiometer having a pair of terminals which is adapted for varying the impedance between said pair of terminals in accordance with the steering angle of said inside steerable wheel in said one direction, said wheel speed signal being connected for transfer between said pair of terminals of said potentiometer for varying the value thereof in accordance with said variation in said impedance between said pair of terminals.

3. A spin control system according to claim 2 wherein said potentiometer includes a resistance element, a slidable contact engageable with said resistance element connected to one of said terminals, a contact connected to said resistors element intermediate the ends of said resistance element and connected to the other of said terminals, and a contact connected to said resistance element at a location spaced from said intermediate contact and connected to a reference potential, said slidable contact being engageable with said resistance element on the opposite side of said intermediate contact relative to said reference potential contact when said inside steerable wheel is steered along a straight course and being movable along said resistance element with steering of said inside steerable wheel in said one direction toward said reference potential contact across said intermediate contact to provide said variation in impedance.

4. A spin control system according to claim 3 wherein said slidable contact is on a rotatable arm for movement of said slidable contact in an arcuate path across said resistance element.

5. A spin control system according to claim 4 wherein said rotatable arm is connected to a steering member of said vehicle for rotation with movement of said steering member.

6. A spin control system according to claim 5 wherein said steering member of said vehicle is a rotatable pitman arm and said rotatable arm of said potentiometer is connected to said pitman arm for rotation therewith.

7. A spin control system for a steerable vehicle having first and second wheels which are driven at least under predetermined conditions and are steerable through varying angles of steering and which are disposed on laterally opposed sides of said vehicle so that an inside one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels comprising:

means for generating a signal representative of the speed of said inside wheel;

means for generating a reference signal;

compensating means for adjusting the value of said reference signal in accordance with the steering angle of said inside steerable wheel so that, absent a spin condition at said inside steerable wheel, the output of said compensating means at the 0°

steering angle position defines a first signal value and for turns in said one direction from a straight course, the value of the output signal from said compensating means is less than said first signal value when the turning radius of said inside steerable wheel is less than the average turning radius of said vehicle, is equal to said first signal value when the turning radius of said inside steerable wheel is equal to the average turning radius of said vehicle, and is greater than said first signal value when the turning radius of said inside steerable wheel is greater than the average turning radius of said vehicle; and

means for comparing said wheel speed signal and said adjusted reference signal for providing a spin signal.

8. A spin control system according to claim 7 wherein said compensating means includes a potentiometer having a pair of terminals which is adapted for varying the impedance between said pair of terminals in accordance with the steering angle of said inside steerable wheel in said one direction, said reference signal being connected for transfer between said pair of terminals of said potentiometer for varying the value thereof in accordance with said variation in said impedance between said pair of terminals.

9. A spin control system according to claim 8 wherein said potentiometer includes a resistance element, a slidable contact engageable with said resistance element connected to one of said terminals, a contact connected to said resistance element intermediate the ends of said resistance element and connected to the other of said terminals, and a contact connected to said resistance element at a location spaced from said intermediate contact and connected to a reference potential, said slidable contact being engageable with said resistance element on the opposite side of said intermediate contact relative to said reference potential contact when said inside steerable wheel is steered along a straight course and being movable along said resistance element with steering of said inside steerable wheel in said one direction toward said reference potential contact across said intermediate contact to provide said variation in impedance.

10. A spin control system according to claim 9 wherein said slidable contact is on a rotation arm for movement of said slidable contact in an arcuate path across said resistance element.

11. A spin control system according to claim 10 wherein said rotatable arm is connected to a steering member of said vehicle for rotation with movement of said steering member.

12. A spin control system according to claim 11 wherein said steering member of said vehicle is a rotatable pitman arm and said rotatable arm of said potentiometer is connected to said pitman arm for rotation therewith.

13. A spin control system for a steerable vehicle having first and second wheels which are driven at least under predetermined conditions and are steerable through varying angles of steering and which are disposed on laterally opposed sides of said vehicle so that an inside one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels comprising:

means for generating a signal representative of the speed of said inside wheel;

means for generating a reference signal;

means for comparing said wheel speed signal and said reference signal for providing a spin signal; and

compensating means for adjusting the value of said spin signal in accordance with the steering angle of said inside steerable wheel so that, absent a spin condition at said inside steerable wheel, the output of said compensating means at the 0°

steering angle position defines a first signal value and for turns in said one direction from a straight course, the value of the output signal from said compensating means is greater than said first signal value when the turning radius of said inside steerable wheel is less than the average turning radius of said vehicle, is equal to said first signal value when the turning radius of said inside steerable wheel is equal to the average turning radius of said vehicle, and is less than said first signal value when the turning radius of said inside steerable wheel is greater than the average turning radius of said vehicle.

14. A spin control system according to claim 13 wherein said compensating means includes a potentiometer having a pair of terminals which is adapted for producing a variable impedance signal between said pair of terminals in accordance with the steering angle of said inside steerable wheel in said one direction, said spin signal being connected to one of said terminals of said potentiometer for varying the value of said signal in accordance with said variable impedance signal.

15. A spin control system according to claim 14 wherein said potentiometer includes a resistance element, a slidable contact engageable with said resistance element connected to one of said terminals, a contact connected to said resistance element intermediate the ends of said resistance element and connected to the other of said terminals, and a contact connected to said resistance element at a location spaced from said intermediate contact and connected to a reference potential, said slidable contact being engageable with said resistance element on the opposite side of said intermediate contact relative to said reference potential contact when said inside steerable wheel is stored along a straight course and being movable along said resistance element with steering of said inside steerable wheel in said one direction toward said reference potential contact across said intermediate contact to provide said variation in said impedance signal.

16. A spin control system according to claim 15 wherein said slidable contact is on a rotatable arm for movement of said slidable contact in an arcuate path across said resistance element.

17. A spin control system according to claim 16 wherein said rotatable arm is connected to a steering member of said vehicle for rotation with movement of said steering member.

18. A spin control system according to claim 17 wherein said steering member of said vehicle is a rotatable pitman arm and said rotatable arm of said potentiometer is connected to said pitman arm for rotation therewith.

19. A spin control system for a steerable vehicle having first and second wheels which are driven at least under predetermined conditions and are steerable through varying angles of steering and which are disposed on laterally opposed sides of said vehicle so that an inside one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels, said vehicle being characterized by a sufficiently small turning radius capability such that for turns in said one direction at progressively greater steering angles of said driven steerable wheels resulting in progressively smaller turning radii, said inside steerable wheel in a first condition has a turning radius less than the average turning radius of said vehicle and hence the speed of said inside steerable wheel is less than the average vehicle speed when no spinning occurs at said inside steerable wheel, thereafter in a second condition has a turning radius equal to the average turning radius of said vehicle and hence the speed of said inside steerable wheel is the same as the average vehicle speed when no spinning occurs at said inside steerable wheel, and still thereafter in a third condition has a turning radius greater than the average turning radius of said vehicle and hence the speed of said inside steerable wheel is greater than the average vehicle speed when no spinning occurs at said inside steerable wheel, said spin control system comprising:

spin detecting means for said inside steerable wheel including wheel speed sensing means for producing a wheel speed signal representative of the rotational speed of said inside steerable wheel, reference speed generating means for producing a reference speed signal related to the average speed of said vehicle, and comparator means for comparing said wheel speed signal to said reference speed signal and producing a spin signal representative of the difference therebetween; and

compensating means responsive to the steering angle of said inside steerable wheel and operatively associated with said spin detecting means for affecting the value of said spin signal for turns in said one direction in accordance with the steering angle of said inside steerable wheel so that, the effective value of said spin signal is increased during said first condition, unaffected during said second condition, and decreased during said third condition.

20. A spin control system according to claim 19 wherein said compensating means includes a potentiometer having a pair of terminals which is adapted for varying the impedance between said pair of terminals in accordance with the steering of said vehicle in said one direction.

21. A spin control system according to claim 20 wherein said potentiometer includes a resistance element, a slidable contact engageable with said resistance element connected to one of said terminals, a contact connected to said resistance element intermediate the ends of said resistance element and connected to the other of said terminals, and a contact connected to said resistance element at a location spaced from said intermediate contact and connected to a reference potential, said slidable contact being engageable with said resistance element on the opposite side of said intermediate contact relative to said reference potential contact when said vehicle is steered along a straight course and being movable along said resistance element with steering of said vehicle in said one direction toward said reference potential contact across said intermediate contact to provide said variation in impedance.

22. A spin control system according to claim 21 wherein said slidable contact is on a rotatable arm for movement of said slidable contact in an arcuate path across said resistance element.

23. A spin control system according to claim 22 wherein said rotatable arm is connected to a steering member of said vehicle for rotation with movement of said steering member.

24. A spin control system according to claim 23 wherein said steering member of said vehicle is a rotatable pitman arm and said rotatable arm of said potentiometer is connected to said pitman arm for rotation therewith.

25. For a vehicle having first and second wheels which are driven at least under predetermined conditions and steerable in at least one direction through varying steering angles and which are disposed on laterally opposite sides of said vehicle so that one of said wheels is disposed closer to the center of turning of said vehicle during steering in one direction than the other of said wheels, a spin control system responsive to a signal related to the speed of said one wheel comprising:

steering angle compensating means having a transfer characteristic for adjusting the value of said signal in accordance with the steering angle of said wheels including an input terminal for receiving said signal and an output terminal for providing said adjusted value signal and means for varying the transfer characteristic of said steering angle compensating means between said input terminal and said output terminal during steering of said wheels in said one direction from a straight course in accordance with variations in said steering angle, such that for a progressively increasing steering angle in said one direction said transfer characteristic has an initial predetermined nonzero value for a zero degree steering angle, thereafter a value progressively approaching zero from said predetermined non-zero value, still thereafter a value progressively approaching said predetermined non-zero value as the steering angle of said wheels correspondingly approaches the condition wherein the turning radius of said one wheel equals the average turning radius of said vehicle, and still further thereafter a value progressively exceeding said non-zero value as the steering angle of said wheels correspondingly surpasses the condition wherein the turning radius of said one wheel equals the average turning radius of said vehicle.

26. A spin control system according to claim 25 wherein said transfer characteristic is an impedance between said input terminal and said output terminal.

27. A spin control system according to claim 26 wherein said compensating means comprises a potentiometer having said input and output terminals and which is adapted for varying the impedance between said input and said output terminals in accordance with the steering of said vehicle in said one direction, said signal being connected for transfer between said input and output terminals of said potentiometer for varying the value thereof in accordance with said variation in said impedance between said terminals.

28. A spin control system according to claim 27 wherein said potentiometer includes a resistance element, a slidable contact engageable with said resistance element connected to one of said terminals, a contact connected to said resistance element intermediate the ends of said resistance element and connected to the other of said terminals, and a contact connected to said resistance element at a location spaced from said intermediate contact and connected to a reference potential, said slidable contact being engageable with said resistance element on the opposite side of said intermediate contact relative to said reference potential contact when said vehicle is steered along a straight course and being movable along said resistance element with steering of said vehicle in said one direction toward said reference potential contact across said intermediate contact to provide said variation in impedance.