Method for determining a likely internal pressure for a master brake cylinder and device for determining a likely internal pressure for a master brake cylinder

Patent metadata

Field	Value
Publication number	US-9789860-B2
Application number	US-201414900930-A
Country	US
Kind code	B2
Filing date	Jun 12, 2014
Priority date	Jun 26, 2013
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

A method for determining a likely internal pressure for a master brake cylinder including: estimating/measuring a displacement path(s) of a brake input element configured on a master cylinder from initial position thereof; estimating/measuring a first hydraulic fluid volumetric flow rate of a hydraulic fluid of the braking system out of or into a first pressure chamber of the master cylinder, and of a second hydraulic fluid volumetric flow rate of the hydraulic fluid out of or into a second pressure chamber of the master cylinder; and determining the likely internal pressure for a master cylinder considering the estimated/measured displacement path(s), the estimated and/or measured first hydraulic fluid volumetric flow rate, and the estimated and/or measured second hydraulic fluid volumetric flow rate. Also described is a device for determining a likely internal pressure for a master brake cylinder, and an electromechanical brake booster, ESP control, and vehicle braking system.

First claim

What is claimed is:

1. A method for determining a likely internal pressure for a master brake cylinder, the method comprising:
at least one of estimating or measuring a displacement path(s) of a brake input element on a master brake cylinder from an initial position thereof;
at least one of estimating or measuring a first hydraulic fluid volumetric flow rate of a hydraulic fluid of the braking system out of or into a first pressure chamber of the master brake cylinder, and a second hydraulic fluid volumetric flow rate of the hydraulic fluid out of or into a second pressure chamber of the master brake cylinder;
determining the likely internal pressure for a master brake cylinder at least taking into account the estimated or measured displacement path(s), the estimated or measured first hydraulic fluid volumetric flow rate, and the estimated or measured second hydraulic fluid volumetric flow rate; and
controlling at least one braking system component based on the determined likely internal pressure for the master brake cylinder.

2. The method of claim 1 , wherein the likely internal pressure for a master brake cylinder is determined while additionally taking into account at least one of: at least one measured master brake cylinder pressure value, or at least one measured admission pressure.

3. The method of claim 1 , wherein the likely internal pressure for a master brake cylinder is determined while additionally taking into account at least one of: a compression module of the hydraulic fluid, an output volume of the master brake cylinder when the brake input element is in the initial position thereof, an inner diameter of the master brake cylinder, or a cross-sectional area of the master brake cylinder.

4. The method of claim 3 , wherein to determine the likely internal pressure for a master brake cylinder, a rate of pressure change is continuously determined where:

dp
MC

dt

=

k

V
0

-

π
·

d
2

4

·
s

·

(

q

MC
⁢

⁢
1

+

q

MC
⁢

⁢
2

+

π
·

d
2

4

·

ds
dt

)

,

dp MC /dt being the rate of pressure change, K being a compression module of the hydraulic fluid, V 0 being an output volume of the master brake cylinder, d being an inner diameter of the master brake cylinder, q MC1 being the first hydraulic fluid volumetric flow rate, q MC2 being the second hydraulic fluid volumetric flow rate, s being the displacement path(s), and ds/dt being an estimated or measured rate of change of displacement path(s) of brake input element and/or an estimated or measured adjustment speed of the brake input element.

5. The method of claim 3 , wherein to determine the likely internal pressure for a master brake cylinder, the rate of pressure change is continuously determined where:

dp
MC

dt

=

k

V
0

-

A
·
s

·

(

q

MC
⁢

⁢
1

+

q

MC
⁢

⁢
2

+

A
·

ds
dt

)

,

dp MC /dt being the rate of pressure change, K being a compression module of the hydraulic fluid, V 0 being an output volume of the master brake cylinder, A being a cross-sectional area of the master brake cylinder, q MC1 being the first hydraulic fluid volumetric flow rate, q MC2 being the second hydraulic fluid volumetric flow rate, s being the displacement path(s), and ds/dt being the estimated or measured rate of change of the displacement path(s) of the brake input element and/or the estimated or measured adjustment speed of the brake input element.

6. The method of claim 4 , wherein the likely internal pressure for a master brake cylinder is determined as the integral over the rate of pressure change where:

p
MC

⁡

(
t
)

=

p

Assignees

• Bosch Gmbh Robert

Inventors

• Bunk Michael

Classifications

• B60T8/4291

  having means to reduce or eliminate pedal kick-back · CPC title

• B60T8/172 Primary

  Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters {(B60T8/17551 takes precedence)} · CPC title

• B60T7/042

  by electrical means, e.g. using travel or force sensors · CPC title

• B60T13/662

  characterised by specified functions of the control system components · CPC title

• B60T8/38

  including valve means of the relay or driver controlled type · CPC title