Electronic control device for a braking system, suitable for a distance control system

• US 9,205,819 B2
• Filed: 01/28/2010
• Issued: 12/08/2015
• Est. Priority Date: 01/28/2010
• Status: Active Grant

• Current Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Original Assignee: Continental Teves AG & Co. OHG (Continental AG)
• Inventors: Schmidt, Robert, Bohn, Joachim, Hitzel, Michael
• Primary Examiner(s): Burch, Melody
• Application Number:
  US13/575,864
• Publication Number:
  US 20130026818A1
• Time in Patent Office: 2,140 Days
• Field of Search: 303/3, 303/11, 303/15, 303/113.1, 303/115.4, 303/116.1, 303/119.2, 303/DIG.1, 303/DIG.2
• US Class Current: 1/1
• CPC Class Codes: B60T 13/18 with control of pump output delivery , e.g. by distributor valves B60T13/167 takes precedence
• CPC Class Codes: B60T 13/20 with control of pump driving means
• CPC Class Codes: B60T 8/36 including a pilot valve responding to an electromagnetic force
• CPC Class Codes: B60T 8/4059 involving the rate of delivery
• CPC Class Codes: B60T 8/4872 pump-back systems

Abstract

An electronic control device for a pressure controller, by way of which solenoid valves for pressure control are actuated with current via an actuating electronic system, and having a pump assembly is actuated as a function of a pressure request, which generates a volumetric flow with a periodically fluctuating amplitude. The wheel brake circuit isolating valve, during an active pressure build-up, discharging part of the delivery volume into a reservoir volume, at least in the case of a control operation which performs an intervention for driving stability which is not critical to safety, if the pressure which is built up by the assembly is higher than the pressure which is to be set, the electric coil current for the actuation of the isolating valve is modulated and the periodic actuation being interrupted at least when the control device has to carry out an intervention for driving stability which is critical to safety.

Claims

1. An electronic control device comprising a controller which carries out a pressure control operation in a motor vehicle braking system by adjusting electric current driving solenoid valves for pressure control via an electronic unit, the electronic control device comprising:

a plurality of solenoid valves including at least one wheel brake circuit isolating valve, at least one wheel brake pressure inlet valve, and at least one wheel brake pressure outlet valve,

a pump assembly actuated as a function of a pressure request that comprises an active pressure build up phase independent of brake actuation by a vehicle driver comprising, wherein the pump assembly generates a volumetric flow of hydraulic brake fluid with a periodically fluctuating amplitude,

wherein, in response to a control operation that performs an intervention for driving stability comprising a distance control operation for adaptive cruise control, the at least one wheel brake circuit isolating valve, during the active pressure build-up phase, discharges part of the delivery volume of the hydraulic brake fluid in a metered manner into a reservoir volume, if the fluid pressure which is built up by the pump assembly is higher than a predetermined pressure,

wherein the electric current for the actuation of the at least one wheel brake circuit isolating valve is modulated periodically, the cycle of the modulation corresponding to a cycle of the volumetric or pressure fluctuation which is caused by the pump assembly, wherein the cycles correspond such that the at least one wheel brake circuit isolating valve discharges the part of the delivery volume when the fluid pressure built up by the pump assembly is higher than the predetermined pressure and limits discharging when the fluid pressure built up by the pump assembly is lower than the predetermined pressure, and

wherein the periodic modulation of the at least one wheel brake circuit isolating valve is interrupted at least when the control device has to carry out an intervention for driving stability comprising control operations of skid control or road handling control.

2. The control device as claimed in claim 1, further comprising in that the modulation is influenced by a signal of a position detection means of the pump assembly.

3. The control device as claimed in claim 1, further comprising in that the cycle for the pressure modulation is derived from the electronic unit for the at least one wheel brake circuit isolating valve.

4. The control device as claimed in claim 1 further comprising in that an electronic evaluation of a plunger position of the at least one wheel brake circuit isolating valve is performed and a change in a magnetic flux is determined via an induction signal of a current loop in a magnetic circuit of the at least one wheel brake circuit isolating valve, the induction signal having signal oscillations, and the signal oscillations of the induction signal are analyzed in order to determine a movement frequency.

5. The control device as claimed in claim 1 further comprising in that the actuating current of the at least one wheel brake circuit isolating valve is adjusted by means of a current controller.

6. The control device as claimed in claim 1 further comprising in that the motor current of an electric motor which actuates the pump assembly is modulated while the motor is revolving.

7. The control device as claimed in claim 1 further comprising in that the pump assembly comprises two reciprocating pistons.