DE102015224517A1 - Hydraulic cylinder for a clutch actuation system or brake actuation system with a displacement encoder - Google Patents

Abstract

Hydraulic cylinder for a clutch actuation system or brake actuation system, comprising a housing, a piston axially displaceable in the housing and a displacement measuring system for detecting a position of the piston in the housing, wherein the displacement measuring system comprises an information transmitter attachable to the piston and a detection unit fixedly arranged relative to the housing, wherein the information transmitter is at least partially locatable in a centering of the piston and wherein the centering has a snap hook for axially securing the information transmitter to the centering, wherein a position indicator can be arranged in two mounting positions on the centering, wherein a first mounting position represents a false structure of the information transmitter and a second mounting position represents a correct installation of the information transmitter.

Description

The present invention relates to a hydraulic cylinder for a clutch actuation system or brake actuation system with a displacement measuring system. With such hydraulic cylinders friction clutches in particular for a drive train of a motor vehicle can be engaged and disengaged and brake systems for motor vehicles actuated.

In particular, such hydraulic cylinders may be used as master cylinders of clutch actuation systems. The master cylinder is activated via a brake pedal or clutch pedal, which is in operative connection with a piston rod of the master cylinder. A generated in the master cylinder hydraulic pressure is transmitted via a filled with hydraulic fluid line system to a slave cylinder, which causes there a displacement of a working piston and thus can operate, for example, a clutch release. In order to detect switching points or to determine the piston position, such hydraulic cylinders may comprise a displacement measuring system with a sensor attached to a piston of the hydraulic cylinder information transmitter, such as a magnet, and arranged on a housing of the hydraulic cylinder detection unit. Usually, the information transmitter is fastened to the piston, which is coupled to the piston rod and represents the movable component of the master cylinder, while the detection unit, for example a sensor, is arranged or integrated on the housing fixed relative to the piston. It is known, for example, to glue the information transmitter to a centering of the piston. The disadvantage here, however, is that adhesive devices are expensive to maintain in automated production lines and have a comparatively low productivity. Furthermore, it is known to attach information transmitter to a centering device by means of additional clips. However, such clips are additional components, on the one hand cause high costs and on the other hand a high installation cost. Often there is also a game between such clips and the information provider, which can lead to electrical interference.

From the previously unpublished DE 10 2015 201 643.9 a hydraulic cylinder with a piston and a centering for the piston is known. In the centering a magnet is arranged, which cooperates with a detection unit in the housing. The magnet can be inserted over a second end face of the centering and is fixed in the centering by a snap hook. However, a faulty mounting of the magnet is possible. Thus, by a fitter z. B. are difficult to determine whether the magnet was actually pushed to an end stop in the centering. However, an incorrect positioning leads to erroneous measurement results of the detection unit.

The object of the invention is therefore to solve the problems described with reference to the prior art at least partially and in particular to provide a hydraulic cylinder for a clutch actuation system or brake actuation system, in which an information transmitter with low assembly costs at a centering can be fastened, the installer feedback to be given to the correct or wrong positioning of the information provider.

This object is achieved with a hydraulic cylinder according to the features of the independent claim. Further advantageous embodiments of the invention are specified in the dependent formulated claims. It should be noted that the features listed individually in the dependent claims can be combined in a technologically meaningful manner and define further embodiments of the invention. In addition, the features specified in the claims are specified and explained in more detail in the description, wherein further preferred embodiments of the invention are shown.

The hydraulic cylinder according to the invention for a clutch actuation system or brake actuation system comprises a housing, a piston axially displaceable in the housing and a displacement measuring system for detecting a position of the piston in the housing, wherein the displacement measuring system comprises an information transmitter attached to the piston and a detection unit fixedly arranged relative to the housing wherein the information transmitter is at least partially disposed in a centering of the piston and wherein the centering has a snap hook for axially securing the information transmitter to the centering and wherein a position indicator can be arranged in two mounting positions on the centering, wherein a first mounting position a false appearance of the information transmitter represents and a second installation position represents a correct installation of the information provider.

The previously unpublished DE 10 2015 201 643.9 is hereby incorporated by reference. In the present invention, a position indicator is additionally proposed, which is also inserted over the second end face of the centering in the centering. The position indicator allows a clear statement as to whether a wrong construction is a correct installation of the information provider.

The hydraulic cylinder proposed here is in particular a Master cylinder for a clutch actuation system or brake actuation system. The hydraulic cylinder is activated in particular via a brake pedal or clutch pedal, which in particular is in operative connection with a piston rod of the hydraulic cylinder. A hydraulic pressure generated in the hydraulic cylinder is transmitted in particular via a line system filled with hydraulic fluid to a slave cylinder, which causes there a displacement of a working piston and thus can actuate, for example, a clutch release. The hydraulic cylinder has a housing in which a piston is axially displaceable. The housing and / or the piston may at least partially made of metal and / or plastic. Furthermore, the hydraulic cylinder has a position measuring system for detecting a position of the piston in the housing. In particular, the displacement measuring system comprises an information transmitter fixed to the piston and a detection unit fixedly arranged relative to the housing. The information provider is in particular a magnet. The information transmitter is at least partially arranged in a centering of the piston. For fixing the information transmitter to the centering, the centering on a snap hook. The snap hook is preferably also at least partially made of metal and / or plastic and is in particular made in one piece with the centering. The snap hook is designed in particular as a strut.

In particular, the centering is arranged on a first end face of the piston and has on the side facing away from the first end face a second end face, wherein the information transmitter via the second end face along a second axial direction in the centering to at least one axial end stop can be inserted and thereby displaces the elastically arranged snap hook, so that the snap hook presses the information transmitter with a second radial force against at least one axial guide in the centering, wherein when the information provider abuts the end stop, the snap hook secures the information transmitter additionally with an axial force on the centering ,

In particular, the information transmitter can be arranged, at least partially, in the centering position between the end stop and a hook of the snap hook, at least partially.

Furthermore, the centering in particular has at least one elastically deformable spring element that is displaced upon insertion of the information transmitter so that the spring element presses the information transmitter with a first radial force against the axial guide. The spring element also preferably consists at least partially of metal and / or plastic and is in particular also designed in one piece with the centering. The at least one spring element may also be a shock absorber.

The information transmitter is at least partially insertable in an axial direction of the centering along the axial guide in the centering. The at least one axial guide also prevents release of the information transmitter in a radial direction of the centering. By pressing the information transmitter to the at least one axial guide by means of the at least one spring element a game of the information transmitter is avoided in the centering, so that the information transmitter is arranged stationarily in the centering.

Moreover, it is advantageous if the hydraulic cylinder has a first spring element and a second spring element, wherein the snap hook is arranged between the first spring element and the second spring element. In other words, this means that the first spring element and the second spring element are arranged in two opposite radial directions relative to the snap hook. The snap hook, the first spring element and the second spring element are oriented in particular in an axial direction of the centering.

Moreover, it is advantageous if the snap hook extends in a first axial direction. The first axial direction extends, in particular in the direction of a second end face of the centering. Moreover, it is advantageous if the at least one spring element extends in a second axial direction. The second axial direction points in particular away from the second end face of the centering and / or points in a direction opposite to the first axial direction.

Moreover, it is advantageous if the snap hook secures the information transmitter with an axial force on the centering and presses against the at least one axial guidance of the centering with the second radial force. The snap hook thus secures the information transmitter in particular without backlash and / or in an axial direction of the centering. Furthermore, the second radial force leads to an additional assurance and play-free attachment of the information transmitter to the centering.

Moreover, it is advantageous if the hydraulic cylinder has at least one first axial guide and one second axial guide, wherein the first axial guide and the second axial guide at least partially have an L-shaped cross section.

The information provider is during assembly at the centering in particular by the first Axial guide and the second axial guide in the axial direction feasible.

In particular, the position indicator can be inserted via the second end face and along the second axial direction into a receptacle of the centering.

In particular, in both installation positions, the position indicator is secured against displacement in a first axial direction opposite to the second axial direction by a form-locking connection with the centering acting in this first axial direction.

In the first installation situation, the position indicator preferably forms an auxiliary mounting surface for the arrangement of the information transmitter, so that a guide for the information transmitter is provided at least in a radial direction during insertion of the information transmitter into the centering by the auxiliary mounting surface.

In particular, the position indicator contacts the snap hook in the second installation position and supports it at least in a radial direction.

In particular, in the first installation position, the position indicator projects beyond the second end face of the centering. This makes it clear to the fitter of the information provider that if the position indicator is not displaceable into the second installation position (in which he would no longer protrude beyond the second end face) there is a false housing and the information transmitter must be re-arranged in the centering.

In particular, the information transmitter can be inserted into the centering via the second end face along a second axial direction and via the position indicator preassembled in the first installation position.

• a) Bereitstellen eines Kolbens mit einer Zentrierung, wobei die Zentrierung an einer ersten Stirnfläche des Kolbens angeordnet ist und auf der, der ersten Stirnfläche abgewandten Seite eine zweite Stirnfläche aufweist;
• b) Bereitstellen eines Positionsindikators;
• c) Einschieben des Positionsindikators über die zweite Stirnfläche und entlang der zweiten axialen Richtung in eine Aufnahme der Zentrierung in eine erste Einbauposition;
• d) Bereitstellen eines Informationsgebers;
• e) Einstecken des Informationsgeber über die zweite Stirnfläche entlang einer zweiten axialen Richtung in die Zentrierung, so dass dabei der elastisch angeordnete Schnapphaken verdrängt wird, so dass der Schnapphaken den Informationsgeber mit einer zweiten radialen Kraft gegen zumindest eine Axialführung in der Zentrierung andrückt;

wobei, wenn der Positionsindikator nicht über die erste Einbauposition hinaus entlang der zweiten axialen Richtung verschiebbar ist, auf einen Falscheinbau des Informationsgebers geschlossen wird und, wenn der Positionsindikator weiter in die zweite Einbauposition verschiebbar ist, auf einen korrekten Einbau geschlossen wird.It is further proposed a method for ensuring a correct installation of an information transmitter in a centering of a piston of a hydraulic cylinder according to the invention, comprising at least the following steps:

• a) providing a piston with a centering, wherein the centering is arranged on a first end face of the piston and on the side facing away from the first end face has a second end face;
• b) providing a position indicator;
• c) inserting the position indicator on the second end face and along the second axial direction in a recording of the centering in a first installation position;
• d) providing an information provider;
• e) insertion of the information transmitter on the second end face along a second axial direction in the centering, so that in this case the elastically arranged snap hook is displaced, so that the snap hook presses the information transmitter with a second radial force against at least one axial guide in the centering;

wherein, when the position indicator is not slidable beyond the first installation position along the second axial direction, a misconstruction of the information transmitter is inferred and, if the position indicator is further slidable to the second installation position, closed to a correct installation.

The comments on the procedure apply equally to the hydraulic cylinder and vice versa.

The invention and the technical environment will be explained in more detail with reference to FIGS. It should be noted that the figures show a particularly preferred embodiment of the invention, but this is not limited thereto. The same components are provided in the figures with the same reference numerals. They show schematically:

1 a hydraulic cylinder in a perspective view;

2 a piston with a centering in a first perspective view and method steps a) and b);

3 : the piston according to 2 with a centering in a second perspective view and method step c);

4 : the piston with centering according to 3 in a side view in section;

5 : the centering according to 4 in a plan view in section;

6 a centering in a first perspective view and method step d);

7 : the centering according to 6 in a second perspective view and step e);

8th : the centering according to 7 in a side view in section;

9 : the centering according to 8th in a further side view in section;

10 : the centering according to 9 in a plan view in section;

11 : a centering in a side view in section;

12 : the centering according to 11 in a plan view in section; and

13 : the centering according to 11 and 12 in a perspective view in section.

The 1 shows a hydraulic cylinder 1 for a not shown here Kupplungsbetätigungssystem or brake actuation system. The hydraulic cylinder 1 has a housing 2 in which a piston 3 in an axial direction 21 is relocatable. At a first end face 12 of the piston 3 is a centering 6 for an information provider not shown here 4 arranged. The information provider 4 is together with one on the housing 2 arranged detection unit 5 Part of a path measuring system.

The 2 and 3 show a piston 3 with a centering 6 in two different perspective representations and method steps a) to c). The centering 6 is at a first end face 12 of the piston 3 arranged and points to the, the first end face 12 opposite side a second end face 18 on, being the information provider 4 (not shown here) over the second end face 18 along a second axial direction 14 in the centering 6 up to axial Endanschläg 19 . 20 can be inserted while the elastically arranged snap hook 7 (please refer 3 ) repressed

The information provider 4 is in an axial direction 21 the centering 6 along the axial guides 9 . 10 in the centering 6 at least partially insertable. The axial guides 9 . 10 also prevents a loosening of the information provider 4 in a radial direction 29 the centering 6 , The radial direction 29 extends from a central axis 31 of the piston 3 transverse to the axial direction 21 ,

The position indicator 24 is over the second face 18 and along the second axial direction 14 in a recording 27 the centering 6 insertable.

4 shows the piston 3 with centering 6 according to 3 in a side view in section (the comments on 2 and 3 apply accordingly). In the 4 Section shown is through the line IV in 5 Are defined. The centering 6 is at a first end face 12 of the piston 3 arranged and points to the, the first end face 12 opposite side, a second end face 18 on. Here is the snap hook 7 recognizable, extending in the first axial direction 13 extends. Next points the centering 6 spring elements 8th . 9 on, with the snap hook 7 between the first spring element 8th and the second spring element 9 is arranged (see also 5 ). In other words, this means that the first spring element 8th and the second spring element 9 in two opposite radial directions 29 relative to the snap hook 7 are arranged. The snap hook 7 , the first spring element 8th and the second spring element 9 each extending in an axial direction 21 the centering 6 , Here, the spring elements extend 8th . 9 in a second axial direction 14 , The second axial direction 14 points from the second end face 18 the centering 6 away and in a direction to the first axial direction 13 opposite axial direction 21 , The axial guides 8th . 9 have at least partially an L-shaped cross-section.

5 shows the centering 6 according to 4 in a plan view in section. In the 5 Section shown is through the line V in 4 Are defined. Here is the position indicator 24 over the second end face 18 and along the second axial direction 14 in a recording 27 the centering 6 in a first installation position 25 shown inserted (step c)). The position indicator 24 is in the illustrated first installation position 25 against displacement in one, the second axial direction 14 opposite first axial direction 13 by (only) in this first axial direction 13 acting positive connection 30 with the centering 6 secured.

6 shows a centering 6 in a first perspective view and method step d), accordingly the information provider 4 provided.

7 shows the centering 6 according to 6 in a second perspective view and method step e), accordingly the information provider 4 over the second end face 18 along a second axial direction 14 in the centering 6 was inserted, so that while the elastically arranged snap hook 7 is displaced so that the snap hook 7 the information provider against the axial guides 10 . 11 in the centering 6 presses. Furthermore, the centering points 6 elastically deformable spring elements 8th . 9 on, when inserting the information provider 4 be displaced so that the spring elements 8th . 9 the information provider 4 with a first radial force 15 against the axial guides 10 . 11 press down.

8th shows the centering 6 according to 7 in a side view in section. Here it can be seen that the information provider 4 at the end stops 19 . 20 is arranged so that the snap hook 7 the information provider 4 with an axial force 17 at the centering 6 secures and with the second radial force 16 against the axial guides 10 . 11 the centering 6 presses. The snap hook 7 secures the information provider 4 thus free of play and in an axial direction 21 the centering 6 between the end stops 19 . 20 and the hook 23 , Furthermore, the second radial force leads 16 for an additional security and play-free attachment of the information provider 4 at the centering 6 ,

In addition, the information provider 4 through the spring elements 8th . 9 in the radial direction 29 against the axial guides 10 . 11 pressed. By pressing the information provider 4 to the axial guides 10 . 11 by means of the spring element 8th . 9 through the first radial force 15 becomes a game of the information provider 4 in the centering 6 avoided, so the information provider 4 stationary in the centering 6 is arranged.

On the information provider 4 so does a resultant force 22 ,

9 the centering 6 according to 8th in a further side view in section. In the 9 Section shown is through the line IX in 10 Are defined. Here is the position indicator 24 in the second installation position 26 , so by a fitter on a correct installation of the information provider 4 can be closed. In this second installation position 26 contacted the position indicator 24 the snap hook 7 and supports it at least in a radial direction 29 from. The position of the information provider 4 at the end stops 19 . 20 and on the axial guides 10 . 11 is guaranteed. Next sticks the position indicator 24 in the second installation position 26 not over the second face 18 the centering 6 out. This is for the fitter of the information provider 4 Clear that a correct installation of the information provider 4 is done.

10 shows the centering 6 according to 9 in a plan view in section, wherein the in 10 sectional area shown by the line X in 9 is defined. The position indicator 24 is in the illustrated second mounting position 26 in the recording 27 against displacement in one, the second axial direction 14 opposite first axial direction 13 by (only) in this first axial direction 13 acting positive connection 30 with the centering 6 secured.

11 shows a centering 6 in a side view in section, wherein the in 11 sectional area shown by the line XI in 12 is defined. 12 shows the centering 6 according to 11 in a plan view in section, wherein the in 12 sectional area shown by the line XII in 11 is defined. 13 shows the centering 6 according to 11 and 12 in a perspective view in section. In the 11 to 13 is the information provider 4 not shown correctly mounted. The information provider 4 does not contact the end stops 19 . 20 , The snap hook 7 is in the radial direction 29 displaces and pushes the information provider 4 with a second radial force against the axial guides 10 . 11 , In addition, the spring elements press 8th . 9 the information provider 4 with a first axial force 15 against the axial guides 10 . 11 , Because the snap hook 7 not in the radial direction 29 spring back, the position indicator can 24 not even from the first installation position 25 in the second mounting position 26 be moved. The position indicator 24 stands out for the fitter recognizably over the second end face 18 addition, so that on a wrong construction of the information provider 4 can be closed.

In the 4 to 13 is the position indicator 24 shown. It can be seen that the position indicator 24 in the first installation situation 25 a mounting aid surface 28 for the arrangement of the information provider 4 training, so while inserting the information provider 4 in the centering 6 through the mounting aid surface 28 a guide for the information provider 4 at least in a radial direction 29 is provided.

LIST OF REFERENCE NUMBERS

1

 hydraulic cylinders

2

 casing

3

 piston

4

 information provider

5

 detection unit

6

 centering

7

 snap hooks

8th

 first spring element

9

 second spring element

10

 first axial guidance

11

 second axial guide

12

 first end face

13

 first axial direction

14

 second axial direction

15

 first radial force

16

 second radial force

17

 axial force

18

 second end face

19

 first end stop

20

 second end stop

21

 axial direction

22

 resulting power

23

 hook

24

 position indicator

25

 First installation position

26

 Second installation position

27

 admission

28

 Mounting auxiliary surface

29

 radial direction

30

 connection

31

 axis

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015201643 [0003, 0007]

Claims (10)

Hydraulic cylinder ( 1 ) for a clutch actuation system or brake actuation system, comprising a housing ( 2 ), one in the housing ( 2 ) axially displaceable piston ( 3 ) and a position measuring system for detecting a position of the piston ( 3 ) in the housing, wherein the displacement measuring system one on the piston ( 3 ) mountable information provider ( 4 ) and one opposite the housing ( 2 ) fixedly arranged detection unit ( 5 ), the information provider ( 4 ) at least partially in a centering ( 6 ) of the piston ( 3 ) and wherein the centering ( 6 ) a snap hook ( 7 ) for the axial securing of the information transmitter ( 4 ) at the centering ( 6 ), wherein a position indicator ( 24 ) in two installation positions ( 25 . 26 ) at the centering ( 6 ) can be arranged, wherein a first installation position ( 25 ) a false sign of the information provider ( 4 ) and a second installation position ( 26 ) a correct installation of the information provider ( 4 ). Hydraulic cylinder ( 1 ) according to claim 1, wherein the centering ( 6 ) at a first end face ( 12 ) of the piston ( 3 ) and on the, the first end face ( 12 ) facing away from a second end face ( 18 ), the information provider ( 4 ) over the second end face ( 18 ) along a second axial direction ( 14 ) in the centering ( 6 ) up to at least one axial end stop ( 19 . 20 ) can be inserted while the elastically arranged snap hook ( 7 ), so that the snap hook ( 7 ) the information provider ( 4 ) with a second radial force ( 16 ) against at least one axial guide ( 10 . 11 ) in the centering ( 6 ), where, if the information provider ( 4 ) at the end stop ( 19 . 20 ), the snap hook ( 7 ) the information provider ( 4 ) additionally with an axial force ( 17 ) at the centering ( 6 ) secures. Hydraulic cylinder ( 1 ) according to claim 2, wherein the centering ( 6 ) at least one elastically deformable spring element ( 8th . 9 ), that upon insertion of the information provider ( 4 ) is displaced so that the spring element ( 8th . 9 ) the information provider ( 4 ) with a first radial force ( 15 ) against the axial guidance ( 10 . 11 ). Hydraulic cylinder ( 1 ) according to one of the preceding claims, wherein the position indicator ( 24 ) over the second end face ( 18 ) and along the second axial direction ( 14 ) into a recording ( 27 ) of centering ( 6 ) can be inserted. Hydraulic cylinder ( 1 ) according to claim 4, wherein the position indicator ( 24 ) in both installation positions ( 25 . 26 ) against displacement in one, the second axial direction ( 14 ) opposite first axial direction ( 13 ) by a, in this first axial direction ( 13 ) acting positive connection ( 30 ) with the centering ( 6 ) is secured. Hydraulic cylinder ( 1 ) according to one of the preceding claims, wherein the position indicator ( 24 ) in the first installation situation ( 25 ) an auxiliary mounting surface ( 28 ) for the order of the information provider ( 4 ), so that during insertion of the information provider ( 4 ) in the centering ( 6 ) through the auxiliary mounting surface ( 28 ) a guide for the information provider ( 4 ) at least in a radial direction ( 29 ). Hydraulic cylinder ( 1 ) according to one of the preceding claims, wherein the position indicator ( 24 ) in the second installation position ( 26 ) the snap hook ( 7 ) and supported at least in a radial direction. Hydraulic cylinder ( 1 ) according to one of the preceding claims, wherein the position indicator ( 24 ) in the first installation position ( 25 ) over the second end face ( 18 ) of centering ( 6 protrudes). Hydraulic cylinder ( 1 ) according to one of the preceding claims, wherein the information provider ( 4 ) over the second end face ( 18 ) along a second axial direction ( 14 ) and in the first installation position ( 25 ) pre-assembled position indicator ( 24 ) in the centering ( 6 ) can be inserted. Method for ensuring the correct installation of an information provider ( 4 ) into a centering ( 6 ) of a piston ( 3 ) of a hydraulic cylinder ( 1 ) according to one of the preceding claims, comprising at least the following steps: a. Providing a piston ( 3 ) with a centering ( 6 ), whereby the centering ( 6 ) at a first end face ( 12 ) of the piston ( 3 ) and on the, the first end face ( 12 ) facing away from a second end face ( 18 ) having; b. Providing a position indicator ( 24 ); c. Inserting the position indicator ( 24 ) over the second end face ( 18 ) and along the second axial direction ( 14 ) into a recording ( 27 ) of centering ( 6 ) in a first installation position ( 25 ); d. Provision of an information provider ( 4 ); e. Inserting the information provider ( 4 ) over the second end face ( 18 ) along the second axial direction ( 14 ) in the centering ( 6 ), so that thereby the elastically arranged snap hook ( 7 ) is displaced so that the snap hook ( 7 ) the information provider ( 4 ) with a second radial force ( 16 ) against at least one axial guide ( 10 . 11 ) in the centering ( 6 ) presses; where if the position indicator ( 24 ) not above the first installation position ( 25 ) along the second axial direction ( 14 ) is displaceable, on a false structure of the information provider ( 4 ) and when the position indicator ( 24 ) further in the second installation position ( 26 ) is displaceable, is closed to a correct installation.

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