WO2022073552A1 - Shifting device - Google Patents

Abstract

The invention relates to a shifting device (1) for the powertrain of a motor vehicle, comprising: a housing (2) in which a first and a second drive shaft (3, 4) are rotatably mounted, said first and second drive shafts (3, 4) being coaxial to each other such that the driveshafts have a common rotational axis (5), and a shiftable clutch device (6) which is arranged between the first and second drive shafts (3, 4), wherein the clutch device (6) has an open shift position in which the first drive shaft (3) is freely rotatable relative to the second drive shaft (4), and the clutch device (6) has a closed shift position in which the first drive shaft (3) is rotationally fixed to the second drive shaft (4) via the clutch device (6); the clutch device (6) comprises a clutch element (7) which is stationary in the direction of the rotational axis (5) and a clutch element (8) which is movable in the direction of the rotational axis (5); a control element (9) which can be moved in the direction of the rotational axis (5) via a drive (10) is provided; the drive (10) preforms a rotary movement and the control element (9) can be moved along the rotational axis (5) via the drive (10).

Description

designation of the invention

switching device

description

field of invention

The invention relates to a shifting device for decoupling two connected output shafts, or a decoupling device with a shifting mechanism, in an electromechanical drive train of a motor vehicle.

Background of the Invention

The application relates to a switching device for decoupling two connected output shafts for a drive train of a motor vehicle according to the preamble of independent claim 1 .

DE 10 2014 217 066 A1 discloses a clutch for an engageable all-wheel drive, in which two aligned drive shafts are connected to one another by a clutch part, which enables a positive connection between the two drive shafts. The clutch has a switching element in the form of a shift fork, with which a clutch part that can be displaced in the axial direction is displaced in such a way that the positive connection between the two drive shafts is established.

A coupling arrangement for a drive train of a motor vehicle is known from WO 2011/098 595 A1, which comprises at least one clutch which is arranged on a rotating shaft in order to selectively couple the rotating shaft to a drive element of the drive train. The coupling arrangement includes furthermore at least one actuating device for actuating the clutch. The actuator is configured to selectively engage an engagement portion with a threaded portion rotating with the shaft to cause relative movement of the engagement portion and the threaded portion in the direction of the axis of the rotating shaft and thereby actuate the clutch in the axial direction.

It is the object of the present application to provide an improved shifting device for a drive train of a motor vehicle.

The object is solved by the features of the independent claim. Further preferred embodiments of the invention can be found in the dependent claims, the figures and the associated description.

This is achieved in a simple manner by means of a rotationally operated drive, which is positively engaged with a control element in such a way that the rotational movement of the drive is translated into a translational movement of the control element and the control element can thus be displaced in the direction of the axis of rotation of the drive shafts, which also a sliding coupling element is shifted in the same direction. The coupling device between the two drive shafts is thus disengaged and no torque is transmitted from one drive shaft to the other. The displaceable coupling element is arranged on a drive shaft, so that a relative displacement can take place in the direction of the axis of rotation, but this drive shaft and the displaceable coupling element arranged thereon can jointly perform a rotary movement.

In one embodiment of the invention, the clutch device is formed by a claw clutch. One embodiment of the invention provides that the control element is mounted relative to the displaceable coupling element in such a way that the control element moves the displaceable coupling element along the axis of rotation, with the control element and the displaceable coupling element being able to rotate in opposite directions.

In an advantageous embodiment of the invention, the displaceable coupling element is mounted via a roller bearing relative to the control element such that it can rotate about the axis of rotation.

A spring element is preferably provided by the drive, with the spring element supporting the movement of the displaceable clutch element from the open switching position into the closed switching position through its pretension. The spring element can be arranged on the drive itself, for example as a torsion spring, on the control element and/or on the displaceable coupling element.

In one embodiment of the invention, the displaceable clutch element is moved from the open switch position into the closed switch position by the positive connection between the control element and the drive. This form fit can be designed with different geometrical shape pairings, which can convert a rotational movement into a translational movement. For example, by means of a pin arranged eccentrically to the axis of rotation of the drive, which engages in a groove or link, the control element being displaced by eccentric rotation of the pin about the axis of rotation of the drive.

In an advantageous embodiment of the invention, the displaceable coupling element is non-rotatably connected to one or the second drive shaft, preferably by means of teeth.

A specification of the invention provides that the control element has a control link and the drive has a pin, the pin being in the control link is placed engaging and translates the rotational movement of the drive into a translational movement of the control element. As an alternative to a pin, other engagement elements that can implement the function of converting movement (rotation into translation) can also be considered. Of course, the shape of the control link is also important for this, in particular in the contact area of the pin with the control link when the drive is actuated.

In a preferred embodiment of the invention, the control element is designed as a non-rotationally symmetrical component. The control element is preferably designed as a plate or flat component.

In a further embodiment of the invention, the control element has a guide link with which the control element is guided on the housing.

The invention is explained below on the basis of preferred embodiments with reference to the accompanying figures. show:

Figure 1 shows a switching device according to the invention and

FIG. 2 shows the control element of the switching device with its interfaces to the peripheral components.

FIG. 1 shows a switching device 1 with a first drive shaft 3 and a second drive shaft 4 which can be connected to one another in a torque-proof manner via a coupling device 6 .

The second drive shaft 4 comprises two partial shafts which are connected to one another in a torque-proof manner via a toothing 18 . The second drive shaft 4 is mounted at one end in a receptacle 19 of the first drive shaft 3 and via a ball bearing 20 opposite a housing 2. The first drive shaft 3 is inside the housing 2 supported by a ball bearing 21 and by an extension of the second drive shaft 4, which projects into the receptacle 19 of the first drive shaft 3. The first and second drive shafts 3 and 4 are aligned coaxially with one another and therefore rotate about a common axis of rotation 5.

One end of each of the first and second drive shafts 3 and 4 protrudes from the housing 2 . In the assembled state, the first drive shaft 3 can then be connected in a rotationally fixed manner to a differential gear, for example, and the second drive shaft 4 to a drive wheel, for example, or vice versa. At the ends of the first and second drive shafts 3 and 4 facing each other, the clutch device 6 is provided, which comprises a first clutch element 7 assigned to the first drive shaft 3 and a clutch element 8 assigned to the second drive shaft 4 and axially displaceable relative to the second drive shaft 4. The clutch device 6 can be shifted into an open shift position in which the first drive shaft 3 and the second drive shaft 4 are not connected to one another in a rotationally fixed manner. Furthermore, the clutch device 6 can be switched into a closed switching position in which the first drive shaft 3 is connected to the second drive shaft 4 in a torque-proof manner. The clutch device 6 is controlled by means of a control element 9 which can be displaced axially, ie in the direction of the axis of rotation 5 , and is supported by the housing 2 .

When the clutch device 6 is switched from the open to the closed switch position, the control element 9 is moved by a drive 10 in the direction of the immovable clutch element 7 . The drive 10 is preferably designed as an electric motor.

The adjustment movement is controlled by a rotatable drive 10 which engages with a pin 13 in a control link 11 of the control element 9 . The control link 11 is preferably designed as a slot, the two mutually parallel flanks 15, 16 of the slot being in contact with the pin 13 when the adjustment movement is carried out. The flanks 15, 16 of the elongated hole extend in the radial direction to the axis of rotation 5, with this radial extent of the flanks 15, 16 not having to form an intersection with the axis of rotation 5.

The control element 9 is in permanent engagement with the roller bearing 12 which in turn is seated on a peripheral surface of the displaceable coupling element 8 . Ideally, the outer ring 22 of the roller bearing 12 is encompassed by the control element 9 via a form fit on two sides, in order to be able to translate the control element 9 with the roller bearing 12 in both directions. The inner ring 24 of the roller bearing 12 is preferably pressed with the displaceable coupling element 8 and/or brought at least by means of a one-sided form fit, with this connection being able to be additionally secured with a retaining ring. The displaceable coupling element 8 can rotate relative to the control element 9 via the roller bearing 12 .

Between the displaceable coupling element 8 and the second drive shaft 4 there is gearing 18 in the form of straight teeth, which allows a translational relative movement between the displaceable coupling element 8 on the second drive shaft 4, but connects these two components to one another in a torque-transmitting manner in every axial position of the displacement range.

A claw coupling is formed between the displaceable coupling element 8 and the non-displaceable coupling element 7 . This claw coupling includes teeth (claws) arranged on the face side of the coupling elements 7 and 8, which can engage in corresponding tooth gaps of the counterpart.

If the first drive shaft 3 is to be decoupled from the second drive shaft 4 , the drive 10 is actuated, which rotates the pin 13 , which is arranged eccentrically to the axis of rotation of the drive 10 , about the axis of rotation of the drive 10 . The pin 13 thus comes into contact with one of the flanks (here the right flank 16) of the control guide 11 designed as a slot and moves the control element 9 in a translatory manner along the axis of rotation 5 (to the right). The control element 9 is radially spaced from the axis of rotation 5 . Due to the non-displaceable connection of the control element 9, the displaceable coupling element 8 is also displaced along the axis of rotation 5 in the same direction as the control element 9. The displaceable coupling element 8 is arranged coaxially to the axis of rotation 5 and to the drive shaft 4 . By shifting to the right, the dog clutch is disengaged. The teeth move out of the tooth gaps because the sliding coupling element 8 to the non-displaceable coupling element 7 wins at a distance. If sufficient spacing is achieved, in which the teeth have been brought completely out of the tooth gaps, then the first drive shaft 3 is decoupled from the second drive shaft 4; torque can no longer be transmitted via the dog clutch. In order to maintain the decoupled state, it is sufficient for the drive 10 to remain in its position, ideally without current, in its position after the shafts have been completely decoupled.

If the first drive shaft 3 is to be coupled to the second drive shaft, the drive 10 is actuated again. The pin 13 rotates and comes into contact with the left flank 15 and thereby pushes the control element 9 in the opposite direction than in the decoupling process. The direction of rotation of the drive 10 is initially irrelevant. The direction of rotation of the drive 10 can be in the same direction as that of the decoupling process or, as a reversal of the direction of rotation, in the opposite direction to this. Via the aforementioned connection between the control element 9 and the displaceable coupling element 8, the coupling element 8 is moved towards the non-displaceable coupling element 7 along the axis of rotation, but in the opposite direction to the previous direction of movement. In the claw coupling, the teeth dip into the tooth gaps, after which the teeth of both coupling elements 7 and 8 are engaged and can transmit torque. In the event that a tooth of the non-displaceable coupling element 7 is opposite a tooth of the displaceable coupling element and consequently no tooth/tooth gap engagement can take place, a spring element can be provided on the drive 10, on the control element 9 or on the displaceable coupling element 8, which the claw coupling closing movement supported.

2 shows the control element 9 of the switching device 1 with its interfaces to the peripheral components. A guide link 14 is formed by the control element 9 orthogonally to the extent of the control link 11 designed as a slot, which also has the shape of a slot. The flanks 17 of this elongated hole extend parallel to the axis of rotation 5. At least one element 19 of the housing 2 or of a component fixed to the housing engages in the guide link 14. Preferably, two spaced-apart elements 19 are provided, arranged along the extension direction of the axis of rotation 5, so that no gravity-related rotation of the control element 9 about a single element 19 has to be additionally supported by the pin 13. Furthermore, the tax relement 9 has a receptacle 23 for the outer ring 22 of the roller bearing 12 . The shape of the receptacle 23 is clearly congruent with the shape of the outer ring 22 of the roller bearing 12.

The pin 13, whose center point intersects the line "coupled", can be moved by turning the drive at least within the "adjustment range" so that the center point of the pin 13 now intersects the line "uncoupled". The states “coupled” and “uncoupled” describe the effects on the states of the coupling device, which either “couples” or “uncouples” the two drive shafts with one another. The intersection of the two lines "coupled" and "decoupled" intersects the axis of rotation of the rotary drive 10. It is thus clearly evident that the pin 13 is arranged eccentrically to this axis of rotation.

1 switching device

2 housing

3 first driveshaft

4 second driveshaft

5 axis of rotation

6 clutch device

7 immovable coupling element

8 sliding coupling element

9 control

10 drive

11 control backdrop

12 roller bearings

13 pen

14 guide backdrop

15 left flank

16 right flank

17 flanks

18 teeth

19 items

20 ball bearings

21 ball bearings

22 outer ring

23 mount (for outer ring)

24 inner ring

25

26

Claims

Claims Switching device (1) for a drive train of a motor vehicle, comprising - A housing (2) in which a first and a second drive shaft (3, 4) are rotatably mounted, the first and second drive shaft (3, 4) being arranged coaxially with one another so that they have a common axis of rotation (5). , and - A switchable clutch device (6) which is arranged between the first and the second drive shaft (3, 4), wherein - The clutch device (6) has an open switching position in which the first drive shaft (3) can rotate freely relative to the second drive shaft (4), and - The clutch device (6) has a closed switching position in which the first drive shaft (3) is connected in a rotationally fixed manner to the second drive shaft (4) via the clutch device (6), wherein - The coupling device (6) comprises a coupling element (7) which cannot be displaced in the direction of the axis of rotation (5) and a coupling element (8) which can be displaced in the direction of the axis of rotation (5), wherein - A control element (9) that can be displaced in the direction of the axis of rotation (5) via a drive (10) is provided, characterized in that - The drive (10) performs a rotary movement and the control element (9) can be displaced in a form-fitting manner along the axis of rotation (5) via the drive (10). Switching device (1) according to claim 1, characterized in that - The coupling device (6) is formed by a claw coupling. Switching device (1) according to any one of the preceding claims, characterized in that - The control element (9) is mounted in relation to the displaceable coupling element (8) in such a way that the control element (9) moves the displaceable coupling element (8) along the axis of rotation, with the control relement (9) and the sliding coupling element (8) can rotate against each other. Switching device (1) according to any one of the preceding claims, characterized in that - The displaceable coupling element (8) is mounted via a roller bearing (12) relative to the control element (9) so as to be rotatable about the axis of rotation (5). Switching device (1) according to any one of the preceding claims, characterized in that - A spring element is provided by the drive (10), the spring element supporting the movement of the displaceable coupling element (8) from the open switching position into the closed switching position by its pretension. Switching device (1) according to any one of the preceding claims, characterized in that - The movement of the displaceable coupling element (8) from the open switching position to the closed switching position takes place through the positive connection between the control element (9) and the drive (10). Switching device (1) according to any one of the preceding claims, characterized in that - The displaceable coupling element (8) is non-rotatably connected to one or the second drive shaft (3, 4). Switching device (1) according to any one of the preceding claims, characterized in that - The control element (9) has a control link (11) and the drive (10) has a pin (13), the pin (13) being placed in the control link (11) and engaging the rotational movement of the drive (10) in a Translated translational movement of the control (9). Switching device (1) according to one of the preceding claims, characterized in that - the control element (9) is designed as a non-rotationally symmetrical component. Switching device (1) according to any one of the preceding claims, characterized in that - The control element (9) has a guide link (14) with which the control element (9) is guided on the housing (2).