阅读说明：本技术 用于机动车摩擦离合器的电液压操纵设备 (Electrohydraulic actuating device for a friction clutch of a motor vehicle ) 是由 弗洛里安·福伊斯陶尔 马库斯·诺斯博克 于 2018-01-11 设计创作，主要内容包括：本发明涉及一种用于机动车摩擦离合器的电液压操纵设备(1),包括踏板单元(2)、执行器单元(7)、离合器单元(13)、控制单元(18)以及第一传感器元件(6)和第二传感器元件(12),其中控制单元(18)与第一传感器元件(6)和第二传感器元件(12)信号连接并且具有第一调控组件以及第二调控组件,其中根据电液压操纵设备(1)的运行状态,第一调控组件经由第二传感器元件(12)的信号并且第二调控组件经由第一传感器元件(6)和第二传感器元件(12)的信号确定用于从动活塞(S<Sub>从动活塞</Sub>)的调节行程的期望值,并且电动机(8)调控所述期望值。(The invention relates to an electrohydraulic actuating device (1) for a friction clutch of a motor vehicle, comprising a pedal unit (2), an actuator unit (7), a clutch unit (13), a control unit (18) and a first sensor element (6) and a second sensor element (12), wherein the control unit (18) is in signal connection with the first sensor element (6) and the second sensor element (12) and has a first control assembly and a second control assembly, wherein depending on an operating state of the electrohydraulic actuating device (1), the first control assembly determines a signal for a driven piston (S) via the second sensor element (12) and the second control assembly determines a signal for the driven piston (S) via the first sensor element (6) and the second sensor element (12) Driven piston ) And the motor (8) regulates the desired value of the stroke.)

1. An electro-hydraulic actuating device (1) for a friction clutch of a motor vehicle, comprising:

-a pedal unit (2) having a clutch pedal (3) and a master cylinder (4) with a master piston (5), wherein the master piston (5) can be actuated by mechanical actuation of the clutch pedal (3) by a master piston stroke (S)_{Active piston}) The movement is carried out in such a way that,

-a first sensor element (6), wherein the first sensor element (6) detects a clutch pedal stroke (S) of the clutch pedal (3)_{Clutch pedal}) Or an active piston stroke (S) of the active piston (5)_{Active piston})，

-an actuator unit (7) having an electric motor (8) and an intermediate cylinder (9) having at least one intermediate piston (10) which is hydraulically connected with the master piston (5) via a first pressure line (11), wherein the intermediate piston (10) is movable via the master piston (5) and/or the electric motor (8),

-a second sensor element (12), wherein the second sensor element (12) detects a rotation angle of the electric motor (8),

-a clutch unit (13) having a friction clutch (14) and a slave cylinder (15) having a slave piston (15) which is hydraulically connected with the intermediate piston (10) via a second pressure line (17), wherein the slave piston (17) is movable via the intermediate piston (10),

-a control unit (18), wherein the control unit (18) is in signal connection with the first sensor element (6) and the second sensor element (12) and has a firstA control assembly and a second control assembly, wherein, depending on the operating state of the electrohydraulic actuating device (1), the first control assembly determines a control path (S) for the slave piston via the signal of the second sensor element (12) and the second control assembly determines the signal of the first sensor element (6) and the second sensor element (12)_{Driven piston}) And the motor (8) regulates the desired value.

2. Electro-hydraulic actuating device (1) according to claim 1,

It is characterized in that the preparation method is characterized in that,

The first control element comprises a characteristic curve, wherein the characteristic curve describes an adjustment path (S) of the slave piston_{Driven piston}) And the clutch torque (y1) of the friction clutch (14).

3. Electro-hydraulic operating device (1) according to claim 1 or 2,

It is characterized in that the preparation method is characterized in that,

The second regulatory component comprises a mathematical relationship, i.e.

S_{Intermediate piston}＝k*S_{Active piston or clutch pedal}

Wherein S_{Intermediate piston}: the adjustment stroke of the intermediate piston (10),

S_{Active piston or clutch pedal}: an active piston stroke of the active piston (5) detected by means of the first sensor element (6) or a clutch pedal stroke of the clutch pedal (3) detected by means of the first sensor element (6), and

k: a scale factor stored in the control unit (18).

4. Electro-hydraulic operating device (1) according to claim 1, 2 or 3,

It is characterized in that the preparation method is characterized in that,

The electrohydraulic actuation device has a third sensor element (19), wherein the third sensor element (19) is in signal connection with the control unit (18), and wherein the third sensor element (19) is arranged in the second pressure line (17) and detects a pressure in the second pressure line (17).

Technical Field

The invention relates to an electrohydraulic actuating device for a friction clutch of a motor vehicle.

Background

A conventional hydraulic actuating device for a motor vehicle clutch, in particular a friction clutch, has a master cylinder and a slave cylinder. The master cylinder is connected in a compensating reservoir filled with hydraulic fluid and comprises a master piston which can be acted upon with force and displaced via an actuating mechanism, such as a clutch pedal. The master cylinder and the slave cylinder are hydraulically connected via a pressure line. The slave cylinder can be, for example, a slave cylinder with a cylindrical piston, but alternatively can be a so-called central decoupler with an annular piston arranged concentrically with respect to the transmission input shaft. If the clutch pedal is actuated mechanically, i.e. by foot, by the vehicle driver, the pressure generated in the master cylinder is transmitted via the fluid column in the pressure line to the slave cylinder. As a result, the release element of the clutch is acted upon by an actuating force via the slave cylinder piston in order to displace the clutch pressure plate via the release mechanism, thereby releasing the engine from the transmission of the motor vehicle.

Modern motor vehicles are increasingly being subjected to demands, such as, for example, greater power with the lowest possible fuel consumption. The greater power of the motor vehicle results in the fact that the motor vehicle clutch has to transmit higher and higher torques. As a result, the size of the motor vehicle clutch is set to be larger and larger, which is accompanied by a great increase in the operating force for disengaging the motor vehicle clutch. In the conventional hydraulic actuating devices as described above, this leads to a high force requirement at the clutch pedal, as a result of which the actuating feel of the clutch pedal for the vehicle driver is significantly influenced in a negative manner. Solutions for this are known from the prior art, in which a master piston, for example a master cylinder, for example US4,918,921 or optionally for example US5,002,166, is always force-loadable and movable via a transmission that can be driven by means of an electric motor.

such clutch actuation devices often require complex control to adapt them to the different operating states of the actuation device.

Disclosure of Invention

The object of the present invention is to provide an electrohydraulic actuating device for a friction clutch of a motor vehicle, which is characterized by a simple and cost-effective design that allows different operating states of the actuating device to be adapted.

The object is achieved by an electrohydraulic actuation device for a friction clutch of a motor vehicle, comprising: a pedal unit having a clutch pedal and a master cylinder having a master piston, wherein the master piston is movable with a master piston stroke via mechanical manipulation of the clutch pedal; a first sensor element, wherein the first sensor element detects a clutch pedal stroke of a clutch pedal or an active piston stroke of an active piston; an actuator unit having an electric motor and an intermediate cylinder having at least one intermediate piston which is hydraulically connected to the drive piston via a first pressure line, wherein the intermediate piston is movable via the drive piston and/or the electric motor; a second sensor element, wherein the second sensor element detects a rotation angle of the motor; a clutch unit having a friction clutch and a slave cylinder having a slave piston hydraulically connected with an intermediate piston via a second pressure line, wherein the slave piston is movable via the intermediate piston; a control unit, wherein the control unit is signal-connected to the first and second sensor elements and has a first and a second control assembly, wherein, depending on the operating state of the electrohydraulic actuating device, the first control assembly determines a desired value for the control stroke of the slave piston via the signal of the second sensor element and the second control assembly via the signals of the first and second sensor elements, and the electric motor controls the desired value.

The electrohydraulic system according to the invention comprises a pedal unit, an actuator unit, a clutch unit, a control unit and a first and a second sensor element.

According to the invention, the pedal unit comprises a clutch pedal and a master cylinder. The master cylinder has a master piston which is movable with a master piston stroke via a mechanically actuated clutch pedal.

The first sensor element of the electrohydraulic actuation device detects the clutch pedal travel of the clutch pedal or the active piston travel of the active piston according to the invention. The first sensor element can thus be designed, for example, as a travel sensor. However, it can also be provided that the first sensor element is designed as a rotation angle sensor.

According to the invention, the actuator unit has an electric motor and an intermediate cylinder. The intermediate cylinder according to the invention comprises at least one intermediate piston which is hydraulically connected to the master piston of the master cylinder via a first pressure line. Furthermore, the intermediate piston is movable according to the invention via the active piston and/or the electric motor.

The second sensor element detects the rotation angle of the motor according to the present invention. The second sensor element can thus be configured, for example, as a rotation angle sensor.

The clutch unit according to the invention comprises a friction clutch and a slave cylinder having a slave piston which is hydraulically connected to an intermediate piston via a second pressure line. The slave piston is movable according to the invention via an intermediate piston.

The master cylinder, the intermediate cylinder and the slave cylinder are thus hydraulically connected in series.

According to the invention, the control unit is in signal connection with the first sensor element and the second sensor element. The control unit according to the invention has a first control assembly and a second control assembly, wherein, depending on the operating state of the hydraulic actuating device, the first control assembly determines a desired value for the control path of the slave piston via the signal of the second sensor element and the second control assembly determines the signal of the first sensor element and the second sensor element, and the electric motor controls the desired value

The term "operating state of the electrohydraulic actuation device" includes in particular two operating states, namely a first operating state and a second operating state.

The first operating state describes an operating state of the electrohydraulic actuation device in which the friction clutch is disengaged automatically, i.e., without the driver mechanically actuating the clutch pedal. The operating state is known colloquially as "cruising" and contributes to a large extent to fuel-optimized operation of the motor vehicle.

The second operating state describes an operating state of the electrohydraulic actuation device in which a force-dependent actuation of the mechanical clutch pedal by the driver is supported. In this way, the drivability of the clutch pedal can be accordingly satisfied with the desired driving comfort.

The electrohydraulic actuation device according to the invention allows the friction clutch to be disengaged during driving independently of a disengagement process at the clutch pedal triggered by the driver (first operating state of the electrohydraulic actuation device) and supports the driver during the disengagement process (second operating state of the electrohydraulic actuation device).

The invention is characterized in that the invention is described in the dependent claims, the description and the figures.

The first control element preferably comprises a characteristic curve, wherein the characteristic curve describes a relationship between the adjustment travel of the slave piston and the friction clutch torque.

Furthermore, the second regulatory component comprises a mathematical relationship, i.e.

S_{intermediate piston}＝k*S_{Active piston or clutch pedal}

Wherein S_{Intermediate piston}: the adjustment stroke of the intermediate piston is adjusted,

S_{Active piston or clutch pedal}: an active piston stroke of the active piston detected by means of the first sensor element or a clutch pedal of the clutch pedal detected by means of the first sensor element, and

k: a scale factor stored in the control unit. The scaling factor k can in this case again be a function which is dependent on further influencing variables of the sensor element or the driving state.

In an advantageous embodiment variant of the electrohydraulic actuation device, the electrohydraulic actuation device comprises a third sensor element, wherein the third sensor element is in signal connection with the control unit, and wherein the third sensor element is arranged in the second pressure line and detects the pressure in the second pressure line.

Drawings

The invention is described below with exemplary reference to the drawings.

Fig. 1 shows a schematic view of an electro-hydraulic actuating device.

Fig. 2 shows the characteristic curve "clutch torque relative to the adjustment travel of the output piston" on the one hand and the hysteresis-containing characteristic curve "separating force relative to the adjustment travel of the output piston" on the other hand.

Fig. 3 schematically shows an exemplary embodiment of an intermediate cylinder.

Detailed Description

Fig. 1 shows an electrohydraulic actuating device 1 according to the invention. The electrohydraulic actuation device 1 is used for actuating a friction clutch of a motor vehicle and has a pedal unit 2, an actuator unit 7, a clutch unit 13, a control unit 18, and a first sensor element 6, a second sensor element 12, and a third sensor element 19.

The electrohydraulic control device 1 operates essentially in two operating states, namely a first operating state and a second operating state. The first operating state describes an operating state of the electrohydraulic actuation device 1 in which the friction clutch 14 is automatically disengaged, i.e., disengaged, without the driver mechanically actuating the clutch pedal 3. The second operating state describes an operating state of the electrohydraulic actuation device 1 in which the mechanical actuation of the clutch pedal 3 is supported by the driver in a force-dependent manner.

the pedal unit 2 of the electrohydraulic actuation device 1 has a clutch pedal 3 and a master cylinder 4. The master cylinder 4 has a master piston 5 which can be actuated by a master piston stroke S by mechanically actuating the clutch pedal 3_{Active piston}And (4) moving.

The actuator unit 7 comprises an electric motor 8 and an intermediate cylinder 9. The intermediate cylinder 9 comprises an intermediate piston 10 and a further intermediate piston 20, which are hydraulically connected to the drive piston 5 of the drive cylinder 4 via a first pressure line 11. Furthermore, the intermediate piston 10 and the further intermediate piston 20 are movable via the master piston 5 and/or the electric motor 8.

The clutch unit 13 comprises a friction clutch 14 and a slave cylinder 15 with a slave piston 16. The slave piston 16 is hydraulically connected via a second pressure line 17 with the intermediate piston 10 of the intermediate cylinder 9 and is movable via the intermediate piston 10 of the intermediate cylinder 9.

The master cylinder, the intermediate cylinder and the slave cylinder are thus hydraulically connected in series.

The first sensor element 6 of the electrohydraulic actuating device 1 is arranged in the region of the pedal unit 2 and detects a clutch pedal travel S of the clutch pedal 3_{Clutch pedal}Or the active piston stroke S of the active piston 5_{Active piston}. The first sensor element 6 forms a stroke sensor. The second sensor element 12 is arranged in the region of the actuator unit 7 and detects the angle of rotation of the electric motor 8. The second sensor element 12 is designed as a rotation angle sensor.

The control unit 18 is likewise arranged in the region of the actuator unit 7 and is in signal connection with the first sensor element 6 and the second sensor element 12. The control unit 18 has a first regulating component and a second regulating component. The first control assembly comprises a characteristic curve and is designed such that, in a first operating state of the electrohydraulic actuating device 1, the signal from the second sensor element 12 determines an actuating stroke S for the slave piston_{Driven piston}And the motor 8 regulates the desired value.

The dashed characteristic curve in fig. 2 describes the adjustment stroke S of the slave piston_{driven piston}(X-axis) and clutch torque Y1 (right Y-axis) of the friction clutch 14.

The characteristic curve of the solid line in fig. 2 describes the adjustment stroke S of the slave piston_{Driven piston}(X-axis) and separation force Y2 (left Y-axis).

The disengagement force y2 describes the force that acts on the slave piston 16 via the clutch spring 22.

In a first operating state of the electrohydraulic actuating device 1, the friction clutch 14 is engaged with a clutch pedal path S_{clutch pedal}Or active piston stroke S_{Active piston}Independently of the manipulation. The required clutch torque y1 of the friction clutch 14 is supplied by the vehicle control 26 to the control unit 18. The control path S for the slave piston is determined from the required clutch torque y1, for example 0Nm, of the friction clutch 14 via the characteristic curve stored in the first control assembly_{Driven piston}Is calculated from the expected value of (c). The desired value is forwarded into a regulator cascade for regulating the electric motor 8, which in turn forwards the current and voltage presets to the electric motor. The electric motor 8 moves the intermediate piston 10 of the intermediate cylinder 9 via the spindle drive, thereby in turn moving the oil volume via the second pressure line 17 into the slave cylinder 15 of the clutch unit 13. The slave piston 16 of the slave cylinder 15 moves as a function of the position of the intermediate piston 10 of the intermediate cylinder 9 and sets the transmittable friction torque y1 at the friction clutch 14.

The second control assembly comprises a mathematical relationship and is designed such that in a second operating state of the electrohydraulic actuating device 1, the control path S for the slave piston is determined via the signal of the first sensor element 6_{Driven piston}and the motor 8 regulates the desired value.

The mathematical relationship is

S_{Intermediate piston}＝k*S_{Active piston or clutch pedal}

Wherein S_{Intermediate piston}: the adjustment stroke of the intermediate piston 10 is,

S_{Active piston or clutch pedal}: an active piston stroke of the active piston 5 detected by means of the first sensor element 6 or a clutch pedal of the clutch pedal 3 detected by means of the first sensor element 6, and

k: a scale factor stored in said control unit 18, wherein the scale factor k does not have to be constant.

Operating at electro-hydraulic pressureduring a second operating state of the device 1, the actuator unit 7, more precisely the intermediate piston 10 of the intermediate cylinder 9, is moved with the clutch pedal path S_{Clutch pedal}In relation to or with the active piston stroke S_{Active piston}Relatively to thereby reduce the force at the clutch pedal 3.

If the driver actuates the clutch pedal 3, oil is displaced from the master cylinder 4 via the first pressure line 11 into the intermediate cylinder 9 and from there displaces the intermediate piston 10 of the intermediate cylinder 9. In the present exemplary embodiment, the intermediate cylinder 10 has a further intermediate piston 20. The other intermediate piston 20 of the intermediate cylinder 9 is stopped at a stop 21 and does not move. The driver first feels the reaction force of the clutch spring 22 on the clutch pedal 3. As a result of the mechanical actuation of the clutch pedal 3, the actuator unit 7, more precisely the electric motor 8, readjusts its position via the two intermediate pistons 10, 20 of the intermediate cylinder 9 and guides the intermediate piston 10 of the intermediate cylinder 9. Due to the movement of the electric motor 8, the stop 21 is displaced and the other intermediate piston 20 of the intermediate cylinder 9 is released. The driver now presses on the other intermediate piston 20 of the intermediate cylinder 9 by means of the clutch pedal 3 and feels the tension of the disk spring 23 at the other intermediate piston 20. The properties of the disk spring 23 are decisively responsible for the driver's perception at the clutch pedal 3. In order to form the transition of the force control from the intermediate piston 10 to the further intermediate piston 20 in a smooth manner for the driver, the stops 21, 21' of the two intermediate pistons 10, 20 of the intermediate cylinder 9 are formed elastically.

The third sensor element 19 of the electrohydraulic actuation device 1 is in signal connection with the control unit 18. A third sensor element 19 is arranged in the second pressure line 17 and detects the pressure in the second pressure line 17.

By means of the third sensor element 19, the pressure change during the clutching process is monitored and compared with the characteristic curve "adjustment stroke S relative to the slave piston_{Driven piston}the separation force y2 ". In the event of a deviation, the characteristic curve "is adjusted in a modified manner" in relation to the adjustment stroke S of the slave piston_{driven piston}Thus, the clutch torque y1 ″ can be used to study different thermal and friction-related operating states.

Control ofThe unit 18 is connected to a vehicle regulator 26. Via said connection, the driving state, such as driving speed, gear selection, engine speed, speed of the transmission input shaft, is transmitted, and the characteristic curve or the adjusted characteristic curve "is transmitted relative to the displacement stroke S of the output piston_{driven piston}The clutch torque y1 "acts on the control assembly 6, 12.

List of reference numerals:

1 electrohydraulic operating device

2 Pedal unit

3 Clutch pedal

4 driving cylinder

5 active piston

6 first sensor element

7 actuator unit

8 electric motor

9 middle cylinder

10 intermediate piston

11 first pressure line

12 second sensor element

13 Clutch unit

14 friction clutch

15 slave cylinder

16 slave piston

17 second pressure line

18 control unit

19 third sensor element

20 other intermediate pistons

21, 21' stop

22 clutch spring

23 disc spring

26 vehicle regulator

y1 (of friction clutch) clutch moment

y2 separating force

S_{Intermediate piston}Adjusting stroke of intermediate piston

S_{Driven piston}adjusting stroke of driven piston

S_{Active piston or clutch pedal}Active piston stroke or clutch pedal stroke

k scale factor