Electric brake system for a vehicle

Patent metadata

Field	Value
Publication number	US-11654872-B2
Application number	US-201916447281-A
Country	US
Kind code	B2
Filing date	Jun 20, 2019
Priority date	Dec 22, 2016
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

The invention relates to an electric brake system (1) for a vehicle. The electric brake system (1) comprises electric brake devices (2). The electric brake devices (2) are powered and controlled by redundant capacitor-based power sources (9A, 9B) and redundant control circuits (16A, 16B). The capacitor-based power source (9A, 9B) can be integrated into axle modules (39A, 39B) located close to a vehicle axle (61A, 61B). The capacitor-based power sources (9A, 9B) are recharged by a hub generator, a regeneration power source (32).

First claim

We claim:

1. An electric service brake system ( 1 ) for a vehicle comprising
a) at least one electric service brake device ( 2 ) wherein a service brake force is generated by an electric service brake actuator ( 3 ) and
b) a capacitor-based power source ( 9 ) which
ba) is formed by or comprises a capacitor and
bb) supplies electric power to the service electric brake actuator ( 3 ),

c) a recharging power source ( 32 ), the recharging power source, the capacitor-based power source and the electric service brake device being connected in series in the aforementioned order during normal operation,
d) at least one control device comprising control logic for controlling a flow of electric energy from the recharging power source ( 32 ) to the capacitor-based power source ( 9 ),
e) a brake actuation mode wherein the electric service brake device ( 2 ) is controlled such that a desired brake force is generated, an increasing brake force is generated and/or a previously generated brake force is upheld,
f) wherein the brake actuation mode comprises
fa) a holding sub-mode wherein a locking, fixing or holding device is actuated which keeps a previously generated service brake force of the electric service brake device ( 2 ) constant and wherein the service brake device ( 2 ) is energized on a reduced energization level and
fb) a brake force control sub-mode wherein the service brake force is controlled on the basis of an actual service brake force demand.

2. The electric brake system ( 1 ) of claim 1 , wherein control logic is provided which initiates a supply of electric power from the recharging power source ( 32 ) to the electric brake device ( 2 ) in the case of detecting
a) a failure of the capacitor-based power source ( 9 ),
b) a critical extent of brake actuations per time interval,
c) a low charging level of the capacitor-based power source ( 9 ) and/or
d) a critical changing rate of a charging level of the capacitor-based power source ( 9 ).

3. The electric brake system ( 1 ) of claim 1 , wherein control logic is provided for controlling the flow of energy from the recharging power source ( 32 ) to the capacitor-based power source ( 9 ) dependent on a monitored charging level of the capacitor-based power source ( 9 ).

4. The electric brake system ( 1 ) of claim 1 , wherein control logic is provided for controlling a return flow of electric energy recovered by the electric brake device ( 2 ) during a brake release to the capacitor-based power source ( 9 ) for recharging the capacitor-based power source ( 9 ).

5. The electric brake system ( 1 ) of claim 4 , wherein control logic is provided which switches the electric brake device ( 2 ) between
a) the brake actuation mode wherein the electric brake device ( 2 ) is controlled such that a desired brake force is generated, an increasing brake force is generated and/or a previously generated brake force is upheld,
b) a recovery mode wherein during a release of the electric brake device ( 2 ) energy is recovered by the electric brake device ( 2 ) and recovered energy is transferred to the capacitor-based power source ( 9 ) for recharging the capacitor-based power source ( 9 ).

6. The electric brake system ( 1 ) of claim 5 , wherein control logic for controlling the flow of electric energy between the capacitor-based power source ( 9 ) and the recharging power source ( 32 ) considers a recoverable energy level stored in the applied electric brake device ( 2 ).

7. The electric brake system ( 1 ) of claim 1 , wherein a capacity of the capacitor of the capacitor-based power source ( 9 ) is dimensioned such that after eight full-stroke applications of the electric brake device ( 1 ) a charging level of the capacitor is not less than a charging level required to obtain a predefined security braking performance on a ninth brake application.

8. The electric brake system ( 1 ) of claim 1 , wherein
a) the capacitor-based power source ( 9 ) supplies power to two electric brake devices ( 2 ) located at different vehicle sides of a vehicle axle ( 61 ) or
b) two capacitor-based power sources ( 9 ) supply power to four electric brake devices ( 2 ) of a double axle.

9. The electric brake system ( 1 ) of claim 1 , wherein
a) a first and a second capacitor-based power source ( 9 A, 9 B) are provided, each of them being associated to at least one electric brake device ( 2 A, 2 B) of a respective vehicle axle ( 61 A, 61 B),
b) in a normal operational mode the two capacitor-based power sources ( 9 A; 9 B) are each connected with at least one electric brake device ( 2 A; 2 B) of a respective vehicle axle ( 61 A; 61 B) but separated from the electric brake device(s) ( 2 B; 2 A) of the other vehicle axle ( 61 B; 61 A) and
c) in a failure mode one of the two capacitor-based power sources ( 9 A) is connected to electric brake devices ( 2 A, 2 B) of both vehicle axles ( 61 A, 61 B).

10. The electric brake system ( 1 ) of claim 9 , wherein the capacitor-based power source ( 9 ) is connected via a power control device and/or a brake control device to at least one brake actuator ( 3 ) or electric brake device ( 2 ).

11. The electric brake system ( 1 ) of claim 1 , wherein the capacitor-based power source ( 9 ) is connected via a power control device and/or a brake control device to at least one brake actuator ( 3 ) or electric brake device ( 2 ).

12. The electric brake system ( 1 ) of claim 1 , wherein
a) the capacitor-based power source ( 9 ) and
b) a voltage converting device ( 25 , 26 , 27 , 35 , 36 ), a power control device, a
system control device and/or a control device
are combined into a module ( 39 ) for controlling at least one electric brake device ( 2 ) associated therewith.

13. The electric brake system ( 1 ) of claim 12 , wherein the module ( 39 ) is
a) mounted to a wheel axle unit ( 59 ) which comprises the associated electric brake device ( 2 ),
b) integrated into a wheel axle unit ( 59 ) which comprises the associated electric brake device ( 2 ) or
c) mounted to a chassis in a region close to the wheel axle unit ( 59 ) which comprises the associated electric brake device ( 2 ).

14. The electric brake system ( 1 ) of claim 1 , comprising
a) a first and a second capacitor-based power source ( 9 A, 9 B) and
b) a first control circuit ( 16 A) and a second control circuit ( 16 B),
c) wherein the first and the second capacitor-based power source ( 9 A, 9 B) and/or the first control circuit ( 16 A) and the second control circuit ( 16 B) are each connectable to at least one electric brake actuator ( 3 ) for providing a redundant electric power supply and/or a redundant control and
d) wherein at least one voltage converting device ( 25 ; 35 , 36 ) connects
da) at least one of the capacitor-based power source ( 9 A, 9 B) to the recharging power source and/or
db) the first capacitor-based power source ( 9 A) and the second capacitor-based power source ( 9 B).

15. The electric brake system ( 1 ) of claim 1 , wherein that
a) when using a first capacitor-based power source ( 9 B) in a normal mode the first capacitor-based power source ( 9 B) supplies first windings ( 51 ; 53 ) of the associated electric brake actuator ( 3 ) with electric power and
b) when activating a second capacitor-based power source ( 9 A) in the case of
ba) a detected failure of the capacitor of the first capacitor-based power source ( 9 B),
bb) a detected critical extend of brake actuations per time interval and/or
bc) a detected low energy level of the capacitor-based power source,

the second electric power source ( 9 A) supplies second windings ( 52

Assignees

• Haldex Brake Prod Ab

Inventors

• Nilsson Anders
• Lindqvist Anders
• Nilsson Peter

Classifications

• B60Y2200/143

  Busses · CPC title

• B60W2300/152

  Tractors · CPC title

• B60T7/042 Primary

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

• B60T2270/413

  Plausibility monitoring, cross check, redundancy · CPC title

• B60W30/18127

  Regenerative braking · CPC title