Braking apparatus and method with booster and spoiler

• US 4,170,066 A
• Filed: 08/16/1978
• Issued: 10/09/1979
• Est. Priority Date: 05/10/1977
• Status: Expired due to Term

• Current Assignee: Folke I. Blomberg, Jan-Olov M. Holst
• Original Assignee: Folke I. Blomberg, Jan-Olov M. Holst
• Inventors: Blomberg, Folke I., Holst, Jan-Olov M.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Application Number:
  US05/934,071
• Time in Patent Office: 419 Days
• Field of Search: 303/114, 303/115, 303/116, 303/119, 188/181 A
• US Class Current: 303/114.3
• CPC Class Codes: B60T 13/161 Systems with master cylinder
• CPC Class Codes: B60T 13/52 indirect, i.e. vacuum booster units
• CPC Class Codes: B60T 8/38 including valve means of the relay or driver controlled type

Abstract

In a braking arrangement for a rotating member such as an automotive vehicle wheel and which has a fluid pressure actuated brake for slowing the rotating member together with a booster for increasing the fluid pressure imposed on the brake to a pressure higher than the pressure imposed by an operator, a sensor for signalling the occurrence of an excessive rate of retardation of the braked rotating member and a booster spoiler operatively connected with the booster and the sensor and responsive to a signalled occurrence of an excessive rate of retardation for decreasing the increased fluid pressure imposed by the booster. The booster may be either pneumatic or hydraulic, with corresponding variations in the specific form for the booster spoiler.

Claims

1. A braking arrangement for a rotating member comprising fluid pressure actuated brake means for slowing the rotating member, operator actuated means communicating with said brake means for imposing fluid pressure on said brake means, booster means operatively connected with said operator actuated means for increasing the fluid pressure imposed on said brake means to a pressure higher than the pressure imposed by said operator actuated means and comprising booster cylinder means and hydraulic fluid circulating means operatively communicating with said booster cylinder means for imposing fluid pressure forces thereon, sensor means for signalling the occurrence of an excessive rate of retardation of the braked rotating member, and booster spoiler means operatively connected with said booster means and said sensor means and responsive to a signalled occurrence of an excessive rate of retardation for decreasing the fluid pressure imposed by said booster means, said booster spoiler means comprising reversing valve means controllably interposed between said hydraulic fluid circulating means and said booster cylinder means for diverting fluid pressure forces otherwise imposed by said hydraulic fluid circulating means and for reversing the differential of fluid pressure forces imposed thereacross.

2. Apparatus according to claim 1 wherein said sensor means comprises electrical switch means for electrically signalling occurrence of an excessive rate of retardation and further wherein said booster spoiler means comprises solenoid actuated valve means electrically connected with and responsive to said switch means.

3. A braking arrangement for a rotating member comprising fluid pressure actuated brake means for slowing the rotating member, operator actuated means for imposing fluid pressure on said brake means and comprising brake rod means, booster cylinder means comprising piston means defining a passageway for cooperating with said brake rod means, and thereby operatively connected to said operator actuated means for increasing the fluid pressure imposed on said brake means to a pressure higher than the pressure imposed by said operator actuated means, hydraulic fluid circulating means operatively communicating with said booster cylinder means for imposing hydraulic pressure thereon and comprising reservoir means for containing hydraulic fluid and pump means for circulating hydraulic fluid from said reservoir means through said piston means whereby partial closure of said passageway by said brake rod gives rise to differentials in hydraulic fluid pressure across said piston means, sensor means for electrically signalling the occurrence of an excessive rate of retardation of the braked rotating member, and booster spoiler means operatively connected with said booster cylinder means and said sensor means and comprising solenoid controlled valve means responsive to a signalled occurrence of an excessive rate of retardation for diverting fluid pressure forces otherwise imposed by said circulating means.

4. Apparatus according to claim 3 wherein said controlled valve means comprises return valve means operatively communicating with said pump means and said reservoir means and controllably interposable between said pump means and said booster cylinder means for providing a flow path recirculating hydraulic fluid from said pump to said reservoir means.

5. Apparatus according to claim 3 wherein said controlled valve means comprises reversing valve means operatively communicating with said pump means and said reservoir means and controllably interposable between said pump means and said booster cylinder means for reversing the direction of flow of fluid from said reservoir means through said piston means.

6. A braking arrangement for a rotating member comprising fluid pressure actuated brake means for slowing the rotating member, operator actuated means communicating with said brake means for imposing fluid pressure on said brake means, booster means operatively connected with said operator actuated means for increasing the fluid pressure imposed on said brake means to a pressure higher than the pressure imposed by said operator actuated means and having diaphragm means controllably subjected to a differential thereacross between atmospheric pressure and a pressure less than atmospheric, sensor means operatively connected with the rotating member for signalling the occurrence of an excessive rate of retardation of the member, brake modulator means operatively connected with said brake means and said sensor means and responsive to signalling from said sensor means for decreasing and increasing the fluid pressure imposed on said brake means upon the occurrence of an excessive rate of retardation of the braked rotating member, and booster spoiler means operatively connected with said sensor means and said booster means and said modulator means and responsive to signalling from said sensor means for controllably subjecting said diaphragm means to atmospheric pressure on opposing sides thereof and thereby decreasing the fluid pressure imposed by said booster means during operation of said modulator means.

7. In a method of braking an automotive vehicle including supplying pressurized hydraulic fluid from an operator actuated device, controllably boosting the pressure of the hydraulic fluid to a pressure higher than the pressure supplied from the device by subjecting a diaphragm to a differential thereacross between atmospheric pressure and a pressure less than atmospheric, applying the pressurized hydraulic fluid to a wheel brake, sensing the occurrence of an excessive rate of retardation of the braked wheel and signalling such sensed occurrence, and modulating braking of the wheel in response to such signalling of a sensed occurrence, the improvement comprising controllably subjecting the diaphragm to atmospheric pressure on opposing sides thereof and thereby reducing the boost in the pressure of the hydraulic fluid in response to such signalling of a sensed occurrence and while the modulating of braking is occurring.

8. A method according to claim 7 wherein the step of reducing the boost comprises reducing the pressure of the hydraulic fluid to the pressure supplied from the device.

9. A method according to claim 7 wherein the step of reducing the boost comprises reducing the pressure of the hydraulic fluid to a pressure below the pressure otherwise supplied from the device.