Brake booster device, brake system, and vehicle

Abstract

To improve the reset ability of a brake booster device.SOLUTION: A brake booster device (1) includes a reservoir tank (8) and a master brake cylinder (10) having at least one chamber (12, 17) and at least one piston (22, 23) arranged in the chamber (12, 17). The chamber (12, 17) can be connected to a pressure regulator (14) so that the piston (22, 23) can be at least partially reset by using the pressure regulator (14), wherein the chamber (12, 17) can be connected to the reservoir tank (8), wherein a valve (7, 9) is arranged between the chamber (12, 17) and the reservoir tank (8).SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a brake booster device, a brake system, and a vehicle.

Background Art

[0002] Patent Document 1 discloses a brake device having a clutch that can be switched by a brake pedal to cut off a drive device from a piston cylinder unit.

[0003] Patent Document 2 relates to a method for open-loop control / closed-loop control of amplification of braking force of a brake device.

[0004] Patent Document 3 discloses a brake system for a vehicle.

[0005] Patent Document 4 discloses an electromechanical brake booster device.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

[0007] In a brake booster device having a reservoir tank and a master brake cylinder having at least one chamber and at least one piston disposed within this chamber, the core of the present invention lies in that the chamber is connectable to a pressure regulator, whereby the piston is at least partially resettable using this pressure regulator, and the chamber is connectable to the reservoir tank, and a valve is disposed between the chamber and the reservoir tank.

[0008] The background of the present invention lies in that a pressure regulator can be used to improve the reset ability of the brake booster device. In particular, the pressure regulator is temporarily operable when the reset force decreases due to the high viscosity of the brake fluid at low temperatures or when the reset means fails. In this case, since the valve closes access to the reservoir tank, the pressure generated by the pressure regulator remains within the chamber. The valve is arranged to prevent the backflow of the brake fluid from the chamber into the reservoir tank when the pressure is generated in the chamber by the pressure regulator.

[0009] Other preferred embodiments of the present invention are the subject of the dependent claims.

[0010] According to a preferred embodiment, the valve is configured as a check valve. In this case, the check valve automatically closes when the pressure is generated in the chamber by the pressure regulator and is arranged to prevent the backflow of the brake fluid from the chamber into the reservoir tank.

[0011] It is further advantageous if at least one spring element for applying a reset force to the piston is disposed within the chamber. Thereby, the reset during the normal operation of the brake booster device can be implemented compactly and inexpensively.

[0012] In a preferred form, since it is not necessary to dispose an additional spring element within the region of the mechanical device outside the chamber, in particular, of the brake booster device, the brake booster device can be configured compactly.

[0013] The spring element is advantageous if it is dimensioned such that the spring force of this spring element is sufficient to reset the piston from the braking position to the neutral position during normal operation of the brake booster device. Thereby, the spring force acting against the braking force can be kept small.

[0014] In a preferred form, if the spring force of the spring element is not sufficient to reset the piston to the neutral position, an additional reset force can be applied to the piston using a pressure regulator. Thereby, the pressure regulator is operable to reset the piston to the neutral position if necessary.

[0015] Furthermore, it is advantageous if the spring element is configured as a coil spring arranged on the piston. Thereby, the brake booster device can be configured compactly.

[0016] According to another preferred embodiment, the brake booster device has an electric motor and a mechanical device, and these are used to displace and / or reset the piston.

[0017] In this case, it is advantageous if an additional reset force can be applied to the piston using a pressure regulator if the reset force of the electric motor is not sufficient to reset the piston from the braking position to the neutral position. Thereby, the pressure regulator is operable to reset the piston to the neutral position if necessary.

[0018] The core of the present invention in the braking system is that the braking system has, in particular, the brake booster device, the pressure regulator, and the control device as described in any one of the claims regarding the brake booster device as described above, and in this case, the pressure regulator is drivable by the control device.

[0019] The background of the present invention lies in that the control device is designed to detect cases where the reset force acting on the piston is insufficient to reset the piston to the neutral position. Further, the control device is designed to operate the pressure regulator so as to provide sufficient hydraulic pressure to reset the piston.

[0020] In this case, it is advantageous if the braking system has a vehicle stabilization system and this vehicle stabilization system has a pressure regulator and / or a control device. Thereby, no additional pressure source is required to reset the piston. The braking system can be configured compactly.

[0021] The core of the present invention in a vehicle lies in that the vehicle has a brake booster device as described in any one of the claims regarding the brake booster device as described above or, and / or a braking system as described in any one of the claims regarding the braking system as described above.

[0022] The background of the present invention lies in that the reset ability of the brake booster device is improved.

[0023] The above-described embodiments and developments can be arbitrarily combined with each other as long as they are meaningful. Other possible embodiments, developments and implementations of the present invention include combinations not clearly described of the features of the present invention described in relation to the examples above or below. In this case, in particular, those skilled in the art may add individual aspects as improvements or supplements to the respective basic forms of the present invention.

Brief Description of the Drawings

[0024]

Figure 1

Modes for Carrying Out the Invention

[0025] In the following sections, the present invention will be described using examples in which further features of the present invention become apparent, but the present invention is not limited to the scope of these features. This example is shown in the drawings.

[0026] The brake booster device 1 has an electric motor 6, a mechanical device including a transmission device 5, a spindle 4, and a spindle nut 3, and a master brake cylinder 10 and a reservoir tank 8.

[0027] In the embodiment shown in the drawings, the master brake cylinder 10 has a first chamber 17 and a second chamber 12, and is thereby configured as a tandem master brake cylinder. Optionally, the master brake cylinder 10 may have only a single chamber, and a single piston provided with a single spring element is disposed within this chamber.

[0028] The master brake cylinder 10 has a first piston 22 and a second piston 23. The first piston 22 is disposed within the first chamber 17, and the second piston 23 is disposed within the second chamber 12. The second piston 23 is displaceable using the first piston 22. The first piston 22 is connected to a first spring element 16, and the second piston 23 is connected to a second spring element 11. Each spring element (11, 16) is designed to apply a reset force to each piston (22, 23). The spring elements (11, 16) are configured as coil springs, for example.

[0029] The first chamber 17 is hydraulically connectable to the reservoir tank 8 via a first connection line 24. In this case, a first valve 7 is disposed between the first chamber 17 and the reservoir tank 8.

[0030] The second chamber 12 can be hydraulically connected to the reservoir tank 8 using the second connecting pipeline 25. In this case, a second valve 9 is arranged between the second chamber 12 and the reservoir tank 8.

[0031] The first valve 7 and / or the second valve 9 are each configured as a check valve in a suitable form.

[0032] The master brake cylinder 10 is connected to a brake circuit system (not shown in the drawing) using at least one supply pipeline 26. In a suitable form, each chamber (12, 17) has one supply pipeline 26 connected to one brake circuit respectively.

[0033] The brake booster 1 can be actuated using an operating device 2 that can be connected to, for example, a brake pedal. The operating device 2 is arranged such that the driver's braking force applied to the operating device 2 displaces the spindle 4. The spindle 4 is connected to the first piston 22 and displaces this first piston 22.

[0034] Actuation can mean adjusting the position or moving a mechanical device, whereby the braking action in the friction brake can be promoted or released. For example, the master brake cylinder 10 of the brake booster 1 can be returned from the braking position where the friction brake is actuated to the neutral position.

[0035] For brake force amplification, the electric motor 6 is designed to drive the spindle nut 3 using the transmission 5. The spindle nut 3 is connected to the spindle 4 and is designed to amplify the displacement of the spindle 4. In this case, the anti-rotation plate 20 is connected to the spindle, and this anti-rotation plate 20 prevents the spindle 4 from rotating together with the spindle nut 3. For this purpose, the anti-rotation plate 20 is connected to the tie rod 21 using the bush 19. When the spindle nut 3 rotates, the anti-rotation plate 20 is guided by the tie rod 21, thereby causing the spindle 4 to be displaced and generating a brake pressure within the master brake cylinder 10.

[0036] The spindle 4, the spindle nut 3, the transmission 5, and the anti-rotation plate 20 are arranged within the housing 18.

[0037] The brake booster device 1 is connected to the pressure regulator 14. For this purpose, the first pipeline 15 is arranged between the first chamber 17 and the pressure regulator 14. The second pipeline 13 is arranged between the second chamber 12 and the pressure regulator 14.

[0038] Each pipeline (13, 15) extends through the cylinder housing of the master brake cylinder 10. In this case, each pipeline (13, 15) is arranged such that the volumetric flow rate can flow from the pressure regulator 14 into each chamber (12, 17) at the respective positions of each piston (22, 23).

[0039] The pressure regulator 14 may be held by the brake booster device 1, may be arranged outside the brake booster device 1, may be an independent device, or the drive stability system (ESP) may be able to take over the role of the pressure regulator 14 (if there are many pressure regulators, the ESP may also be called another pressure regulator).

[0040] The pressure regulator 14 may be connected to a pressure accumulator and a pump for the hydraulic fluid or may have these pressure accumulator and pump, and generates a predetermined fluid volume in the master brake cylinder 10 to increase or decrease a predetermined pressure, and a pressure resisting the movement for the braking action can be generated in the master brake cylinder 10 by this predetermined fluid volume.

[0041] The pressure regulator 14 is driven by a control device not shown in the drawings. This control device may be configured as a component of the brake booster 1 or may be configured separately from the brake booster 1, and may be, for example, a control device of an electronic stability program (ESP).

[0042] The pistons (22, 23) in the master brake cylinder 10 can be reset by the hydraulic pressure generated by the pressure regulator 14. In this case, the pressure regulator 14 supports the spring elements (11, 16) when the pistons (22, 23) are reset. The reset force acting on the pistons (22, 23) is the sum of the spring force of the first spring element 16, the spring force of the second spring element 11, and the hydraulic pressure of the pressure regulator 14.

[0043] In this case, the spring elements (11, 16) are dimensioned such that the spring force of the spring elements (11, 16) is sufficient to reset the pistons (22, 23) to the neutral position where no braking force acts on the brake circuit system after the end of the braking operation process during the normal operation of the brake booster 1. In a use example where the spring force of the spring elements (11, 16) is not sufficient to reset the pistons (22, 23), the pressure regulator 14 additionally operates, and this pressure regulator 14 generates an additional pressure for resetting the pistons (22, 23) on the pistons (22, 23). Such a use example exists, for example, in the case of a low temperature causing a high viscosity of the brake fluid.

[0044] Optionally, the motor 6 stops, and the reset of the brake booster device 1 can be actuated during normal operation.

[0045] The control device is designed to calculate the pressure in the master brake cylinder 10 and compare it with a predetermined cylinder pressure. In this case, when the pressure in the master brake cylinder 10 is greater than or equal to the predetermined cylinder pressure and there is no driver braking request, the previous braking operation process and the need for reset are detected.

[0046] In this case, there may be a high internal pressure remaining in the chambers (12, 17), and this internal pressure preferably needs to be reduced by reset. The residual pressure in the chambers (12, 17) itself pushes the pistons (22, 23) back only after the hydraulic force acting on the pistons (22, 23) and the frictional forces in the mechanical device and the connected transmission device 5 are eliminated. To further push the mechanical device and the pistons (22, 23) back to the neutral position, the volume flow rate in the master brake cylinder 10 can be maintained, for example, by a pressure regulator 14 or a pump of a pressure controller. Thereby, a reset force in the pistons (22, 23) that is greater than the frictional force can be achieved.

[0047] The control device is designed to estimate the presence of a driver braking request by calculating information regarding the stopped state of the vehicle and / or the pedal position of the accelerator pedal and / or the position of the vehicle's brake pedal and / or the speed of the vehicle and / or the speed gradient.

[0048] The signals that the control device can receive to actuate the reset function, particularly to operate the pressure regulator 14 for the purpose of reset, may be information regarding the presence of a driver braking request, the measured master brake cylinder pressure, an active brake lamp switch (from which a braking request is inferred), the accelerator pedal position that can read whether it should be accelerated (i.e., not braked) or braked, or the stopped state information of the vehicle.

Description of the Reference Numerals

[0049] 1 Brake booster device 2 Operating device 3 Spindle nut 4 Spindle 5 Transmission device 6 Electric motor 7 First valve 8 Reservoir tank 9 Second valve 10 Master brake cylinder 11 Second spring element 12 Second chamber 13 Second pipeline 14 Pressure regulator 15 First pipeline 16 First spring element 17 First chamber 18 Housing 19 Bush 20 Anti-rotation plate 21 Tie rod 22 First piston 22 First piston 23 Second piston 24 First connecting pipeline 25 Second connecting pipeline 26 Supply pipeline

Claims

1. A brake booster (1) having a reservoir tank (8) and a master brake cylinder (10) having at least one chamber (12, 17) and at least one piston (22, 23) arranged in said chamber (12, 17), 1. A brake booster (1), characterized in that the chamber (12, 17) is connectable to a pressure regulator (14) whereby the piston (22, 23) is at least partially resettable by means of the pressure regulator (14), the chamber (12, 17) is connectable to the reservoir tank (8), and a valve (7, 9) is arranged between the chamber (12, 17) and the reservoir tank (8).

2. 2. Brake booster (1) according to claim 1, characterized in that the valve (7, 9) is designed as a check valve.

3. 3. Brake booster (1) according to claim 1, characterized in that at least one spring element (11, 16) is arranged in the chamber (12, 17) for exerting a reset force on the piston (22, 23).

4. 4. The brake booster (1) according to claim 3, characterized in that the spring elements (11, 16) are dimensioned such that the spring force of the spring elements (11, 16) is sufficient to reset the pistons (22, 23) from the braking position to the neutral position during normal operation of the brake booster (1).

5. 5. The brake booster (1) according to claim 4, characterized in that, if the spring force of the spring elements (11, 16) is not sufficient to reset the pistons (22, 23) to the neutral position, an additional reset force can be applied to the pistons (22, 23) by means of the pressure regulator (14).

6. 6. Brake booster (1) according to claim 3, characterized in that the spring elements (11, 16) are designed as coil springs arranged on the pistons (22, 23).

7. 7. The brake booster (1) according to claim 1, characterized in that the brake booster (1) has an electric motor (6) and a mechanical device, by means of which the pistons (22, 23) can be displaced and / or reset.

8. 8. The brake booster (1) according to claim 7, characterized in that an additional reset force can be applied to the pistons (22, 23) by means of the pressure regulator (14) if the reset force of the electric motor (6) is not sufficient to reset the pistons (22, 23) from the braking position to the neutral position.

9. 9. A brake system comprising a brake booster (1) according to any one of claims 1 to 8, a pressure regulator (14) and a control device, the pressure regulator (14) being drivable by the control device.

10. 10. The braking system according to claim 9, characterized in that the braking system comprises a vehicle stabilization system, which comprises the pressure regulator (14) and / or the control device.

11. A vehicle comprising a brake system according to any one of claims 9 or 10.

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