DE102018101572B3 - Clutch release with movable relative to the piston magnet for detecting the position of the piston - Google Patents

Abstract

The invention relates to a clutch release device (1) for a motor vehicle drive train, with a housing acting as a carrier part (2) relative to which a hollow cylinder-like piston (3) is axially displaceable to move a release bearing (4), wherein between the housing (2 ) and the piston (3) a pressure chamber (5) is present, which causes a displacement of the piston (3) in dependence on its filling, wherein in or on the housing (2) a sensor (6) is fixed, for the position detection of Magnet (7) is designed, wherein the magnet (7) is accommodated in a magnetic holder (8), wherein the magnetic holder (8) on the piston (3) is connected such that between the piston (3) and the magnetic holder (8) a relative movement in the axial direction (A) excluded and in the circumferential direction (U) is possible.

Description

The present invention relates to a clutch release, such as a double-CSC for actuating a dual clutch, for a motor vehicle drive train, with a housing acting as a support member relative to a hollow cylinder-like piston is axially displaceable to move a release bearing, wherein between the housing and a pressure space is provided in the piston, which causes a displacement of the piston relative to the housing in dependence on its filling, wherein a sensor is arranged in or on the housing, which is designed for position detection of a magnet, wherein the magnet is accommodated in a magnet holder.

Release systems for clutches are well known in the art. For example, the DE 10 2012 220 322 A1 a release system for a clutch of a motor vehicle, with at least one within a housing via a pressure chamber acted upon by a pressure medium and axially movable to actuate a release bearing piston, at the pressure chamber side end a sealing element is arranged, and with one of at least one reference transmitter and at least one with This means in operative connection sensor element formed device for position measurement and / or position determination of the piston. The reference transmitter is arranged between the piston and the sealing element.

The WO 2013/017116 A1 discloses a hydraulic cylinder, in particular for a clutch actuator in a motor vehicle, comprising a housing which is concentrically arranged around a shaft and having an annular pressure chamber in which a concentric piston is movably mounted, which is connected to a release bearing, wherein the release bearing a , The axial movement of the piston exporting magnet is arranged, which faces a mounted on the housing sensor, wherein a gap between the magnet and the sensor is formed. In order to prevent effects of a tumbling motion of the release bearing on the signal of the sensor, the magnet is mounted on a magnetic carrier which engages in a magnetic carrier recording of the release bearing.

The publication DE 10 2014 217 118 A1 concerns a release system for a clutch of a vehicle, preferably with hydraulic actuation, in which at least one reference sensor in the form of a magnet or an electrically conductive target is provided for measuring the distance of at least one piston which is displaceable in a housing along a longitudinal axis and is operatively connected to a release bearing , wherein the target is guided in a linear guide, which prevents at least in the radial direction tilting of the target.

The still unpublished EN 10 2017 117 279.3 (AT: 31.07.2017) discloses a clutch release for actuating a clutch in a motor vehicle drive train, comprising a housing in which at least one piston for displacing a release bearing is axially displaceable, and which forms a pressure chamber with the housing, wherein on the housing a sensor is mounted, which is designed for detecting the position of a piston-fixed magnet, wherein on the housing a pocket is formed, which is equipped by a release bearing remote side with the sensor.

The also still unpublished DE 10 2017 115 481.7 (AT: Jul. 11, 2017) discloses a dual solenoid mount used in conjunction with clutch release to receive two magnets for a piston of a hydraulic slave cylinder, the magnets being designed and adapted to, in cooperation with a sensor, provide inference about the position of a piston of the slave cylinder give, where a body has two receiving areas for each magnet, the dimensions of the receiving areas are such that in the inserted state of the magnets in the receiving areas and in the inserted state of the double magnet holder in the piston, the magnets backlash on the body in the for the operation necessary position are held.

Further prior art is in the DE 100 18 633 A1 . DE 10 2008 058 702 A1 , of the DE 10 2014 116 561 A1 , of the DE 10 2015 105 652 A1 , of the DE 10 2012 219 173 A1 as well as the DE 10 2015 223 972 A1 disclosed.

A disadvantage of the prior art is that the radial space for a clutch release this type is very limited, but most sensor systems are mounted as a separate unit in the radial direction of the release system. For this offers the still unpublished EN 10 2017 117 279.3 already an alternative to save radial space and to use the space available in the axial direction sufficient space for the sensor system. However, this is disadvantageous in that the magnets are piston-resistant and can thereby lead to a higher seal wear, because the piston may not rotate relative to the housing, otherwise the position detection by means of the sensor is no longer possible.

The closest prior art according to the preamble of claim 1 is the DE 20 2006 014 024 U1 considered. The described central release for a hydraulic Single clutch comprises a sensor for detecting an axial position of a piston relative to a housing, wherein the sensor is stationarily mounted on the housing and cooperates with a magnet which slidably connected to the axial displacement by the piston during its axial displacement with this axially backlash, but circumferentially is. The document, however, shows no way to provide a corresponding arrangement for double clutches.

The object of the invention is to avoid or at least mitigate the disadvantages of the prior art, and in particular to provide a clutch release for double clutches, in which the radial space can be kept low and the sensor accuracy for determining the position of the piston is high. The object of the invention is achieved in a generic clutch release according to the invention that a second hollow cylinder-like piston is arranged concentrically to the housing in the manner of a double CSC, wherein in or on the housing, a second sensor is set, which is designed for detecting the position of a second magnet, wherein the magnet is accommodated in a second magnet holder, wherein the two magnets ( 7 ) to each other and the two sensors ( 6 ) are arranged circumferentially at different angles to an imaginary horizontal line passing through the center of the clutch release, each magnet ( 7 ) the respective sensor ( 6 ) is opposite in the radial direction.

It is possible that the piston can rotate in the circumferential direction, without this leading to a change in position of the magnets in the circumferential direction. As a result, the wear, in particular on the seals that seal the pressure chamber, reduced.

Advantageous embodiments are claimed in the subclaims. According to the invention, the magnet holder is connected to the housing such that a relative movement in the circumferential direction is excluded between the housing and the magnet holder and made possible in the axial direction.

Thus, the magnetic support with respect. The housing can move in the axial direction to perform the axial movement of the piston with, but their position in the circumferential direction is clearly defined, whereby the magnet is always opposite to the sensor. This ensures that the change in position of the piston can be detected by the sensor via the magnet.

The invention provides that, furthermore, a second hollow-cylinder-like piston is arranged concentrically with the housing in the manner of a double CSC. This means that a second hollow cylinder-like piston is arranged to be relatively axially displaceable on the housing and concentric with the first piston in order to displace a second release bearing, wherein between the housing and the second piston also a pressure chamber is present, which depends on its filling causes a displacement of the second piston relative to the housing. In this case, it is usual for a piston to be arranged inside and a piston outside the housing. This embodiment corresponds, for example, that of a double CSC and serves, for example, for actuating a double clutch.

According to the invention, a second sensor is arranged in or on the housing, which is designed for position detection of a second magnet, wherein the magnet is accommodated in a second magnet holder. In this case, the magnet is connected to the second piston such that a relative movement in the axial direction is excluded between the second piston and the second magnet holder and made possible in the circumferential direction.

Furthermore, it is advantageous if the magnet or the magnets is / are designed as a double magnet / e. The use of double magnets can increase the accuracy of position detection of the piston.

Furthermore, it is advantageous if the sensors are accommodated in a common sensor housing. This simplifies the installation in the housing, since the sensors do not have to be individually positioned and fixed.

Further, it is advantageous if the magnet holder / s is performed by means of rails present in the housing in their axial movement / are. As a result, on the one hand prevents tilting of the magnetic mounts and on the other hand thus the position in the circumferential direction is clearly defined.

It has been found to be advantageous that the guide is made in rails by means of a T-shape or dovetail shape. As a result, the orientation of the magnets or the magnetic holders during installation is clearly specified. In addition, these forms are particularly suitable for axial guidance.

It has proven to be particularly advantageous if the respective magnet holder is connected to the respective piston via a positive connection. A positive connection has the advantage that the assembly or assembly is relatively simple and at the same time a certain orientation of the two part to be joined can be given to each other by the shape. Furthermore a positive connection can be made reversible, which makes any disassembly easy.

It is advantageous if the positive connection is designed as a snap connection or a clip connection. Such a form of positive engagement is easy to install and can also be easily disassembled if necessary.

Further, it is advantageous in this case if the piston has a circumferential groove which serves as a "negative geometry" of the positive connection, that is, into which engages a clip or a nose of the respective magnetic holder for a snap connection. Such a groove is easy to manufacture and allows the desired relative movement in the circumferential direction between the respective piston and the corresponding magnet holder.

An advantageous embodiment provides that the / the magnet / s is arranged below the respective pressure chamber / are. As a result, the available space in the axial direction can be used optimally and space in the radial direction can be reduced.

According to the invention, the magnets and the sensors, viewed in the circumferential direction, are each arranged offset from one another. This means that the two magnets or the two sensors are arranged in the circumferential direction at different angles to an imaginary horizontal extending through the center of the clutch release. This makes it possible to arrange the magnets or the sensors in the radial direction, as it were, at the same radius. Thus, the double CSC requires no additional radial space compared to the single CSC.

For mounting, it has proven to be advantageous if the magnet (s) and the associated sensor (s) are / are introduced into the housing from the release side in the axial direction. As a result, their assembly is independent of the assembly of the / s.

In other words, the invention is that the axial space below the pressure chamber for the placement of the magnets and sensors is used. This is only possible if ever a piston forms a pressure wall. The sensors are mounted offset on the circumference, i. the sensors are at a different angle to the center. This means that the sensors are arranged offset to one another in the circumferential direction. This minimizes the influence of the magnets on the opposite piston on the sensor. The mounting of the magnet holder and the sensors, which are both mounted in a sensor housing, takes place axially from the opposite side from which the pistons are mounted. Therefore, a snap connection is required, and in theory also a press-fit connection or an integral connection, for example, ultrasonic welding or gluing, are possible in order to connect the guided double magnetic holders to the piston. In this arrangement, both sensors can be mounted in a housing and supplied with a cable.

Due to the fact that the two magnet holders are guided independently of the piston and there is only one axial connection, the piston can continue to rotate freely, which leads to a lower seal wear. In addition, the sensor accuracy for positioning is higher because the guide of the magnet holder does not go over several parts and so the positioning of the magnet is defined in more detail. That is, the dynamic mechanical tolerances in all six degrees of freedom are lower.

It can therefore also be said that it is proposed to mount the double magnets for the position detection of the piston of a dual-clutch CSC below the pressure chambers. The magnets are each embedded in a clip, which in turn is connected via a positive connection / snap hook / clip or the like with the piston. The piston forms the pressure chamber wall. Radial between the clips is the sensor.

• 1 eine geschnittene Explosionsdarstellung einer ersten beispielhaften Ausführungsform des Kupplungsausrückers;
• 2 eine Ansicht von unten des Kupplungsausrückers der ersten beispielhaften Ausführungsform;
• 3 den Schnitt III-III aus 2; und
• 4 die Schnittansicht des Schnitts IV-IV in 2.

The invention will be explained in more detail with the aid of figures, in which different embodiments are shown. Show it:

• 1 a sectional exploded view of a first exemplary embodiment of the clutch release;
• 2 a bottom view of the clutch release of the first exemplary embodiment;
• 3 the section III-III 2 ; and
• 4 the sectional view of the section IV-IV in 2 ,

The figures are merely schematic in nature and are only for the understanding of the invention. The same elements are provided with the same reference numerals.

Features of the individual embodiments can also be realized in other embodiments. So they are interchangeable.

1 shows a first exemplary embodiment of a clutch release 1 in an exploded and longitudinal view. Of the clutch release 1 has a housing 2 as well as two pistons 3 on. Each of the pistons 3 is in installation with one release bearing each 4 and serves to move it to actuate a clutch (not shown) in the axial direction. Each of the pistons 3 forms with the housing 2 a pressure room 5 (please refer 3 ) out. This can be filled with a pressure medium and thereby pressurized, resulting in an axial movement of the respective piston 3 and thus the release bearing 4 leads.

In 2 It can be seen that the clutch release 1 also via two sensors 6 each of which is for detecting the position of a magnet 7 (see also 1 ) serves. The magnets 7 are each in a magnetic holder 8th added. The sensors 6 are in a common sensor housing 9 added. Out 2 it will be seen that the two sensors 6 in the sensor housing 9 in the circumferential direction U the clutch release 1 seen staggered to each other. In addition, one of the sensors 6 to the radially outer magnet 7 aligned, whereas the other sensor 6 towards the radially inner magnet 7 is aligned. The embodiment of the clutch release shown here 1 is a so-called double CSC 10 that is, a concentric slave cylinder for actuating, for example, a double clutch. From the 1 . 3 and 4 will be apparent that the housing 2 in the embodiment shown here between the two concentric pistons 3 . 3 is arranged. Thus, the housing forms 2 with each of the pistons 3 one pressure chamber each 5 out. The respective pressure chamber 5 is about seals 11 sealed, each per pressure chamber a piston-tight seal 12 and a housing-tight seal 13 are provided. In the case 2 is a bag 14 (please refer 1 ), which is adapted to receive the sensor housing 9 serves. In addition, the housing faces 2 Guides or rails 15 on, in which the magnets 7 in their magnetic holders 8th are guided in the axial direction. In addition, the rails 15 designed so that a relative movement in the circumferential direction of the clutch release 1 the magnets 7 regarding the housing 2 is suppressed (see also 2 ). The magnets 7 are in the embodiment shown here as double magnets 16 executed.

The pistons 3 have at their release bearing remote, axial end a circumferential groove 17 on, with the groove 17 at the radially inner piston 3 on the outer diameter and the radially outer piston 3 runs at the inner diameter. The magnets 7 are in the magnet holder 8th for example, embedded in a form-fitting or cohesive manner. The magnet holders 8th have a shape which corresponds to the shape of the rail 15 fits, so the magnet mounts 8th in the axial direction A the clutch release 1 guided guided are displaced, but can not move in the circumferential direction and can not tilt in the radial direction.

In addition, the magnetic holders 8th an extension at one axial end 18 on, which at its free end over a nose 19 features. Together, this extension can 18 and the nose 19 as a snap device 20 be designated. Here's the nose 19 designed so that they fit into the respective groove 17 of the piston 3 positively engages. This is the magnetic holder 8th with the respective piston 3 connected so that an axial displacement of the piston 3 also to an axial displacement of the magnet 7 or magnetic holder 8th leads. This allows the circumferential groove 17 that the piston is 3 regarding the magnetic holder 8th can rotate in the circumferential direction, without the magnetic holder 8th rotates. The arrangement and connection of the magnetic holders 8th with the piston 3 is through the sections III-III in 3 respectively. IV - IV in 4 clarified.

Alternatively, the snap device 20 also be designed as a clip.

LIST OF REFERENCE NUMBERS

1

clutch release

2

casing

3

piston

4

release bearing

5

pressure chamber

6

sensor

7

magnet

8th

magnetic holder

9

sensor housing

10

Double-CSC

11

poetry

12

piston-tight seal

13

housing-tight seal

14

bag

15

Guide rail /

16

double magnet

17

groove

18

renewal

19

nose

20

snap device

U

circumferentially

A

axially

Claims (6)

Clutch release device (1) for a motor vehicle drive train, with a housing acting as a carrier part (2) relative to which a hollow cylinder-like piston (3) is axially displaceable to move a release bearing (4), wherein between the housing (2) and the piston (3) a pressure chamber (5) is present, which causes a displacement of the piston (3) in dependence on its filling, wherein in or on the housing (2) a sensor (6) is fixed, which is used for position detection of a magnet (7) is designed, wherein the magnet (7) is accommodated in a magnetic holder (8), wherein the magnetic holder (8) on the piston (3) is connected such that between the piston (3) and the magnetic holder (8) has a relative movement in the axial direction (A) excluded and in the circumferential direction (U) is made possible and the magnet holder is connected to the housing such that between the housing and the magnet holder a relative movement in the circumferential direction excluded and in the axial direction is possible, characterized in that a second hollow cylinder-like piston (3) is arranged concentrically to the housing (2) in the manner of a double CSC (10), wherein in or on the housing (2) a second sensor (6) is fixed, the for the position detection of a second magnet (7) is designed, wherein the magnet (7) in a second magnetic holder (8) is received, wherein the two magnets (7) to each other and the two sensors (6) to each other in the circumferential direction at different angles to a are arranged through the center of the clutch releaser extending imaginary horizontal, each magnet (7) facing the respective sensor (6) in the radial direction. Coupling release (1) according to Claim 1 , characterized in that the magnets (7) as double magnets (16) is / are formed. Coupling release (1) according to Claim 1 or 2 , characterized in that the sensors (6, 6) are accommodated in a common sensor housing (9). Clutch release (1) according to one of Claims 1 to 3 , characterized in that the magnet holders (8) by means in the housing (2) existing rails (15) is guided in its axial movement / are. Clutch release (1) according to one of Claims 1 to 4 , characterized in that the respective magnetic holder (8) with the respective piston (3) is connected via a positive connection. Clutch release (1) according to one of Claims 1 to 5 , characterized in that the magnets (7) are arranged in the axial direction below the respective pressure chamber (5).

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