Method and system for actuating a vacuum pump associated with a brake booster

Patent metadata

Field	Value
Publication number	US-10160432-B2
Application number	US-201615292695-A
Country	US
Kind code	B2
Filing date	Oct 13, 2016
Priority date	Oct 14, 2015
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

A method for actuating an electric vacuum pump of a brake booster including indirectly ascertaining a negative pressure in the brake booster. Depending on the indirectly ascertained negative pressure, and on a pumping capacity of the vacuum pump, ascertaining at least one activation parameter for the vacuum pump. Activating the vacuum pump in accordance with the activation parameter, when the indirectly ascertained negative pressure drops below a predefined minimum value.

First claim

What is claimed is:

1. A method for actuating an electric vacuum pump of a brake booster comprising the steps of:
indirectly ascertaining a negative pressure loss in the brake booster;
determining a pumping capacity of and ascertaining at least one activation parameter for the vacuum pump;
activating the vacuum pump based on said at least one activation parameter when the ascertained negative pressure loss exceeds a predefined value until a negative pressure gain generated by said vacuum pump equals said negative pressure loss.

2. The method of claim 1 wherein the negative pressure loss is caused by the operation of the brake booster and is set off against the negative pressure gain attained by the operation of the vacuum pump.

3. The method of claim 2 wherein the negative pressure loss is ascertained based on an ambient pressure prevailing in the ambient surroundings of the brake booster and a hydraulic brake pressure.

4. The method of claim 2 wherein the negative pressure loss is ascertained based on an ambient pressure prevailing in the ambient surroundings of the brake booster and an operation travel of a brake pedal.

5. The method of claim 2 wherein the negative pressure gain is based on the pumping capacity of the vacuum pump.

6. The method of claim 1 wherein said at least one activation parameter includes an activation period and activating the vacuum pump for the activation period.

7. The method of claim 1 wherein the pumping capacity is a time-dependent value.

8. The method of claim 1 wherein the pumping capacity is based on electrical power supplied to the vacuum pump.

9. The method of claim 1 wherein the pumping capacity is based on a total operating period of the vacuum pump.

10. A method for actuating an electric vacuum pump of a brake booster using a control device comprising the steps of:
indirectly ascertaining a negative pressure in the brake booster; and
depending on the indirectly ascertained negative pressure and on a pumping capacity of the vacuum pump at least one activation parameter for the vacuum pump is ascertained and the vacuum pump is activated in accordance with said at least one activation parameter for an activation period when the indirectly ascertained negative pressure drops below a predefined minimum value wherein an electric target power to be supplied to the vacuum pump is ascertained as said at least one activation parameter, and the vacuum pump is activated during the activation period in accordance with the target power.

11. The method of claim 10 wherein a negative pressure loss caused by the operation of the brake booster is set off against a negative pressure gain attained by the operation of the vacuum pump.

12. The method of claim 11 wherein the negative pressure gain is ascertained based on the pumping capacity of the vacuum pump.

13. The method of claim 10 wherein the pumping capacity is based on the total operating period of the pump.

14. The method of claim 10 wherein the negative pressure loss is ascertained based on an ambient pressure prevailing in ambient surroundings of the brake booster and based on a hydraulic brake pressure operation travel of a brake pedal.

15. A method for actuating an electric vacuum pump of a brake booster using a control device comprising the steps of:
indirectly ascertaining a negative pressure loss in the brake booster; and
depending on the indirectly ascertained negative pressure loss and on a pumping capacity of the vacuum pump ascertaining at least one activation parameter for the vacuum pump, and activating the vacuum pump in accordance with at least one activation parameter when the indirectly ascertained negative pressure loss exceeds a predefined minimum value to provide a negative pressure gain equal to said negative pressure loss.

16. The method of claim 15 including the steps of ascertaining an activation period as an activation parameter; and
activating the vacuum pump for the activation period.

17. The method of claim 15 wherein the pumping capacity is indirectly ascertained as time-dependent value.

18. The method of claim 15 wherein the pumping capacity is ascertained depending on an electrical power supplied to the vacuum pump.

19. A method for actuating an electric vacuum pump of a brake booster comprising the steps of:
indirectly ascertaining a negative pressure in the brake booster;
determining a pumping capacity of and ascertaining at least one activation parameter for the vacuum pump; and
activating the vacuum pump based on said at least one activation parameter for an activation period when the ascertained negative pressure drops below a predefined minimum value wherein said at least one activation parameter includes an electric target power to be supplied to the vacuum pump and activating the vacuum pump during the activation period based on the target power.

20. A method for actuating a brake booster vacuum pump comprising:
indirectly ascertaining a negative pressure loss in the brake booster;
determining a pumping capacity of the vacuum pump;
activating the vacuum pump using a target power supplied to the vacuum pump for an activation period based on the target power when the negative pressure loss exceeds a predefined value; and
said activation period resulting in a negative pressure gain equaling said negative pressure loss.

Assignees

• Ford Global Tech Llc

Inventors

• Moore Ian
• Schmaler Christian
• Baumann Matthias

Classifications

• B60T13/52

  indirect, i.e. vacuum booster units · CPC title

• B60T13/72 Primary

  in vacuum systems {or vacuum booster units} · CPC title

• B60T17/00

  Component parts, details, or accessories of power brake systems not covered by groups B60T8/00, B60T13/00 or B60T15/00, or presenting other characteristic features (air compressors per se F04) · CPC title

• B60T13/168

  Arrangements for pressure supply · CPC title