DE102017125149B4 - Planetary roller screw, actuator and release system - Google Patents

Abstract

Planetenwälzgewindetrieb (1), in particular as part of an actuator of a disengagement system for a clutch device of a motor vehicle, comprising a threaded spindle (10) and a plurality of the threaded spindle (10) mechanically engaged, about their own longitudinal axis rotatably arranged planetary rollers (20), respectively a cylindrical shoulder (21) in which a plurality of circumferential grooves (22) form a structure which meshes with the thread of the threaded spindle (10), wherein the Planetenwälzgewindetrieb 1 further comprises a planetary roller carrier 30 which supports the planetary rollers 20 at least in the axial direction and Furthermore, the Planetenwälzgewindetrieb 1 has a rotary bearing 40, the inner ring 41 is fixedly connected to the planetary roller carrier 30, characterized in that the Planetenwälzgewindetrieb (1) further comprises an at least two-part cassette (50), which serves for angular position accurate recording of the planetary rollers (20) and di e is supported axially by the planetary roller carrier (30), wherein a cassette part (51) and a second cassette part (52) together form the cassette (50).

Description

The invention relates to a Planetenwälzgewindetrieb, an actuator with the Planetenwälzgewindetrieb and a release system for a coupling device of a motor vehicle.

To operate clutches, usually a translatory travel must be traveled to separate coupling halves from each other or to bring them into engagement. For this purpose, actuators are required, which are also called actuators or actuators, and with which a required force can be generated via a corresponding path. There are for this purpose actuators which convert the rotational movement of a component into an axial movement of another component, e.g. to open or close a clutch.

Typical actuators are hydraulic slave cylinders, or planetary roller screw drives. Planetenwälzgewindespindeltriebe comprise a threaded spindle, a spindle nut and between these circumferentially arranged, received in a planetary roller carrier Planetenwälzkörper. One of the components - threaded spindle or spindle nut is rotationally driven and the other component is displaceable at a rotationally fixed arrangement along the longitudinal axis of the threaded spindle by one of the set translation corresponding axial travel.

The WO 2015/081951 A1 discloses an actuator with planetary roller screw (PWG), which is designed in particular for the actuation of a clutch of a vehicle. The Planetenwälzgewindespindel comprises a central spindle having a pitch, which is rotatably connected to a rotor of a drive and driven with the drive about an axis of rotation. The spindle is engaged by several planetary rollers.

DE 10 2015 204 587 A1 It is known, distributed on the circumference of the threaded spindle to arrange pairs of planetary rollers, which mesh with the threaded spindle and each other. The planetary rollers of a respective pair are identical.

In the post-published DE 10 2017 114 198 A1 a Planetenwälzgewindetrieb is described which has a rotary bearing, wherein the bearing inner ring of the rotary bearing is formed by the planet carrier. The planets used are stepped according to their angular position.

Different Planetenwälzgewindetriebe therefore require a different effort in terms of manufacturing and assembly of individual components, such as the planetary rollers to avoid their confusion during assembly. Furthermore, a different effort to operate in the assembly, since, depending on the design of the planetary rollers, these are to be arranged exclusively at their corresponding angular positions.

Likewise is from the DE 10 2016 222 149 A1 a Planetenwälzgewindetrieb known, in which the bearing inner ring of a rotation bearing itself is part of the planet carrier.

Proceeding from this, the present invention seeks to provide a Planetenwälzgewindetrieb, a method for producing the Planetenwälzgewindetriebs and an actuator with the Planetenwälzgewindetrieb and a release system for a clutch device of a motor vehicle, which require a low manufacturing technology and assembly effort in a structurally simple manner ,

This object is achieved by the Planetenwälzgewindetrieb invention according to claim 1, by a method for producing a Planetenwälzgewindetriebes according to claim 7 and by an actuator with the Planetenwälzgewindetrieb according to claim 8 and by a release system for a clutch device of a motor vehicle with the actuator according to the invention. Advantageous embodiments of the Planetenwälzgewindetriebs invention are given in the dependent claims 2-6.

The features of the claims may be combined in any technically meaningful manner, for which purpose the explanations of the following description as well as features of the figures may be consulted which comprise additional embodiments of the invention.

The Planetenwälzgewindetrieb invention serves in particular as part of an actuator of a release system for a coupling device of a motor vehicle. The planetary roller screw drive comprises a threaded spindle and a plurality of planetary rollers which are mechanically engaged with the threaded spindle and rotatable about their own longitudinal axis, each having a cylindrical shoulder in which a plurality of circumferential grooves form a structure which meshes with the thread of the threaded spindle. Furthermore, the planetary roller screw drive comprises a planetary roller carrier, which supports the planetary rollers at least in the axial direction. In addition, the Planetenwälzgewindetrieb on a rotary bearing, the inner ring is firmly connected to the planetary roller carrier. Accordingly, it is envisaged that the Bearing inner ring and the planetary roller carrier, which is also referred to as a carrier plate, are designed as two separate, interconnected components. The rotary bearing is in particular a rolling bearing, such as a single row ball bearing. The planetary roller carrier thus fulfills the function of the planet carrier and the bearing receptacle for the rotary bearing. Correspondingly lower requirements exist with regard to the complexity of the planetary roller carrier or of the bearing inner ring. The bearing inner ring is thus reduced to its actual bearing function and can be structurally simple. For the mechanical connection of the planetary roller screw drive to the periphery, therefore, only the outer ring of the rotary bearing is to be designed as an interface.

In particular, it is provided that the planetary roller carrier as a substantially hollow cylindrical support plate, which is designed in particular as a deep-drawn part. This hollow cylindrical support plate may comprise two cylinder sections which are coaxial with each other and axially offset.

In one embodiment of the Planetenwälzgewindetriebes is provided that the inner ring of the rotary bearing is positively connected to the planetary roller carrier. This can be carried out in particular by means of a friction fit produced by press-fitting the inside of the bearing inner ring with the lateral surface of a hollow cylinder of the planetary roller carrier. Optionally, the bearing inner ring may be shrunk onto the planetary roller carrier.

According to the invention, the planetary roller screw drive also has an at least two-part cassette which serves to receive the planetary rollers in exact angular position and which is supported axially by the planetary roller carrier.

In particular, it can be provided that the cassette parts are identical. The two cassette parts thus form planetary bearing components for rotation bearing of the planetary rollers. Accordingly, the planetary rollers are preferably also designed as identical components.

For defined positioning of the cassette parts, it is preferably provided that a first cassette part has a first mold element and a second cassette part has a second mold element, wherein the first mold element and the second mold element are complementary in shape and size, so that in mechanical operative connection between the both mold elements, the two cassette parts are positioned defined in terms of their angular position with respect to each other.

In particular, in the embodiment with identical planetary rollers is provided that at least one of the cassette parts, depending to be arranged in the planetary roller has a paragraph different axial extent.

This paragraph is used for the axially offset arrangement of a respective, axially supporting planetary roller to ensure that a respective planetary roller has a defined axial position for clean engagement with the thread of the threaded spindle. The axial position here refers to the longitudinal axis of the centrally arranged threaded spindle.

Furthermore, a friction element for the axial support of a respective planetary roller can be arranged on at least one of the cassette parts. This friction element, which is also referred to as a friction plate, is arranged for example on a bearing journal of a planetary roller or on an end shoulder of the planetary roller. The material combination of planetary roller and friction element should preferably have a coefficient of friction μ 0.15. As a result, friction-related wear, occurring during the transmission of axial forces on or from the planetary rollers to the planetary bearing component, can be reduced in a simple manner.

In addition, at least one of the cassette parts at least a third mold element and the planetary roller support at least a fourth mold element, wherein the third and the fourth mold element are configured in such complementary shape and size to each other, that in a mechanical operative connection between the third mold element and the fourth mold element a rotational relative movement of the respective cassette part is blocked in relation to the planetary roller carrier. This means that a rotational movement of the cassette with the planetary rollers received therein can be blocked by the third mold element and the fourth mold element about the longitudinal axis of the centrally arranged threaded spindle.

In particular, it is provided that the fourth mold element is a bendable sheet metal tongue which engages in the bent state in a complementarily configured third mold element in the form of a recess of a cassette part.

Such a bendable sheet metal tongue is for example made of the sheet material of the planetary roller carrier, which is preferably made as a deep-drawn part of sheet metal, by a cutting-punching process. In detail, this metal tongue can be arranged in the region of the planetary roller carrier, where a smaller hollow cylinder merges into a coaxially arranged next larger hollow cylinder. By cutting a border area of the smaller hollow cylinder can be generated in a simple manner such a bendable sheet metal tongue. After arranging the cassette with the planetary rollers received therein, this sheet metal tongue and preferably a plurality of sheet tabs provided in this way can be bent so that they engage in the recesses provided as third shaped elements. In this way, the cassette with the planetary rollers in the planetary roller carrier can be arranged precisely defined with respect to its axial position in a constructively and assembly-wise simple manner, whereby at the same time the angular position of the cassette is fixed by engagement of the third and fourth form elements.

This constructive embodiment can be embodied in particular at an axial end of the cassette. At the axially opposite end of the cassette, the third and the fourth mold element can be executed by axially nested, positively locking a rotational movement blocking elements.

As another aspect of the present invention, there is provided a method for manufacturing a planetary roller screw drive in which planetary rollers are received in the cassette parts and the cassette parts with the planetary rollers are used as a cassette in an inner space formed by a planetary roller carrier, and then at least a third form element one of the cassette parts, designed in particular as a recess, and at least a fourth form element of the planetary roller carrier, in particular designed as a bendable metal tongue, are brought into a mechanical operative connection with each other, in particular by bending the bendable sheet metal tongue, so that a rotational relative movement of the respective cassette part with respect to the planetary roller carrier is blocked.

It can be seen that the assembly method according to the invention can be carried out with a low constructive and technical or personnel expense in order to ensure an exact and permanently stable arrangement of the cassette with the planetary rollers in the planetary roller carrier.

Another aspect of the present invention is an actuator having a Planetenwälzgewindetrieb invention and a mechanically coupled to the Planetenwälzgewindetrieb rotary drive means for driving an element of the Planetenwälzgewindetriebes for the purpose of realizing a translational movement. The actuator according to the invention may also be referred to as a Modular Clutch Actuator (MCA). The translational motion is performed and utilized by an element of the planetary roller screw, such as the threaded spindle, which is non-rotatably supported, in order to actuate a coupling device for the purpose of opening or closing. For this purpose, the planetary roller carrier of the Planetenwälzgewindetriebes is rotatably connected to a rotor of the drive means, with which the planetary roller carrier is driven about its central axis of rotation, so that there is a translational displacement of the threaded spindle.

The invention additionally provides a release system for a clutch device of a motor vehicle, which has an actuator according to the invention and an interface for transmitting a generated translatory movement to the clutch device

A further subject of the present invention is a system to be actuated, in particular a coupling device which has a release system according to the invention, wherein the release system is adapted to convert a rotational movement of a rotation device into a translational movement for the purpose of actuating a clutch.

• 1: ein erfindungsgemäßer Planetenwälzgewindetrieb in perspektivischer Schnittansicht ohne Gewindespindel;
• 2: ein erfindungsgemäßer Planetenwälzgewindetrieb in perspektivischer Ansicht;
• 3: ein Planetenrollenträger in einer ersten perspektivischen Ansicht;
• 4: der Planetenrollenträger in einer zweiten perspektivischen Ansicht;
• 5: eine Kassette in perspektivischer Ansicht;
• 6: die Kassette in einer perspektivischen Schnittansicht;
• 7: zwei Kassettenteile in perspektivischer Ansicht; und
• 8: ein erfindungsgemäßer Aktuator in perspektivischer Schnittansicht.

The above-described invention will be explained in detail in the background of the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is not limited by the purely schematic drawings in any way, it being noted that the embodiments shown in the drawings are not limited to the dimensions shown. It is shown in

• 1 : An inventive Planetenwälzgewindetrieb in a perspective sectional view without threaded spindle;
• 2 an inventive Planetenwälzgewindetrieb in perspective view;
• 3 a planetary roller carrier in a first perspective view;
• 4 the planetary roller carrier in a second perspective view;
• 5 : a cassette in perspective view;
• 6 : the cassette in a perspective sectional view;
• 7 : two cassette parts in perspective view; and
• 8th : An inventive actuator in a perspective sectional view.

First, the structure of the Planetenwälzgewindetriebes invention is based on the 1 and 2 explained. 1 shows a section through the Planetenwälzgewindetrieb without threaded spindle. 2 shows the same planetary roller with threaded spindle 10 ,

The threaded spindle 10 is the centrally arranged component. With the thread of the threaded spindle 10 comb planetary roles 20 attached to a respective cylindrical heel 21 circumferential grooves 22 exhibit. The planetary roles 20 are about the longitudinal axis 11 the threaded spindle 10 arranged around the circumference. Axially on the side of the cylindrical shoulders 21 arranged, stub axle 23 stuck in a first cassette part 51 and a second cassette part 52 putting together a cassette 50 form. For this purpose are in the cassette parts 51 . 52 mounting holes 53 for receiving the axle journal 23 arranged on their insides planetary bearing surfaces 100 train as it is in 7 is indicated.

In the in the 1 and 2 illustrated embodiment are also axially between the planetary rollers 20 and the cassette parts 51 . 52 friction 63 arranged in the form of friction plates, which together with the material of a journal 23 a planetary role 20 , form a very low friction factor and thus during operation of the planetary roller screw drive 1 cause a low friction.

The cassette 50 with the planetary roles 20 is in a planetary roller carrier 30 arranged. This planetary roller carrier 30 includes a smaller, first hollow cylinder 31 , As well as an axially adjoining larger, second hollow cylinder 32 , At the transition between the two hollow cylinders 31 . 32 is the front side 33 of the second hollow cylinder 32 arranged.

The cassette 50 is in the first hollow cylinder 31 is received and on a first side axially through an axial boundary wall 35 of the first hollow cylinder 31 supported. Here is a first form fit 81 to the first cassette part 51 , On the opposite axial side is the cassette 50 axially through a fourth mold element 60 , here in the form of a bendable tongue 61 executed, supported. This bendable metal tongue 61 is from the front 33 of the second hollow cylinder 32 worked out, namely by the production of a detail 34 in the front side 33 so that the tin tongue 61 after performing a cut generation of the cutout 34 stopped. It can be seen that the cassette 50 in a simple way in the planetary roller carrier 30 or its first hollow cylinder 31 can be inserted and then the bendable sheet metal tongues 61 can be reshaped to the cassette 50 axially fix.

The bendable sheet metal tongues serve this purpose 61 as fourth form element 60 not only the axial fixation, but also the fixation of the cassette 50 in a certain angular position. This is achieved in that a respective bendable tongue 61 in a complementarily configured third form element 57 in the form of a recess 58 engages and so a second positive connection 82 manufactures. At the radial outside of the first hollow cylinder 31 of the planetary roller carrier 30 is a rotary warehouse 40 arranged. The inner ring 41 of the rotation bearing 40 sits with a press fit on the outside of the first hollow cylinder 31 , The rotary bearing 40 includes rolling elements 43 and an outer ring 42 ,

The radial outer side of the second hollow cylinder 32 Optionally serves as a friction surface 80 for arranging an external friction element.

It can be seen that the Planetenwälzgewindetrieb shown here 1 can be produced in a simple manner, since planetary roller carrier 30 and rotary bearings 40 are extra components that are easily assembled to each other. As a rotary warehouse 40 you can use a standard component.

When introducing a torque on the in 2 indicated rotor 90 an electric machine in the planetary roller carrier 30 this is set in rotation and takes the cassette 50 with the planetary roles 20 in the rotary motion with. This will grip the circumferential grooves 22 the planetary roles 20 in the thread of the threaded spindle 10 one so that these translationally along its longitudinal axis 11 is moved. About Drehabstützungen 12 attached to the axial ends of the threaded spindle 10 are arranged, can thus apply force to actuate a coupling device.

In the 3 and 4 is a planetary roller carrier 30 shown in different perspective views. Clearly visible here are the sections 34 that is used to train as the fourth form elements 60 provided bendable sheet metal tongues 61 leads. In the states shown here are the bendable sheet metal tongues 61 not yet so bent that they like in the 1 and 2 shown axially and with respect to the angular position of the cassette 50 can fix, but in a position in which the slot of the cassette 50 in the first hollow cylinder 31 of the planetary roller carrier 30 is still possible.

Out 4 is still the opposite axial side of the planetary roller carrier 30 can be seen, in which case in the axial boundary wall 35 clearly a fourth form element 60 as another recess 62 it can be seen, in which a correspondingly shaped projection 59 who in 5 is shown is pluggable. As a result, in the first hollow cylinder 31 inserted cassette 50 also fixed positively in its angular position.

Furthermore, in 3 a centering surface 91 for receiving the inner ring 41 of the rotation bearing 40 as well as a centering surface 92 for the rotor.

An axial contact surface 93 for the installation of the inner ring 41 of the rotation bearing 40 is out 4 seen.

The cassette 50 is in the 5 and 6 seen. In 5 it is recognizable that the cassette 50 comprises two cassette parts, namely the first cassette part 51 and the second cassette part 52 , which have respective webs 54 mechanically interconnected.

In the cassette 50 are the planetary roles 20 arranged.

The front side faces the cassette 50 as the third form element 57 the lead 59 on, which, as already described, in the recess 62 of the first hollow cylinder 31 is pluggable.

Central in the cassette parts 51 . 52 is each a hole 101 intended for the spindle passage. Furthermore, the third form elements 57 in the form of the recesses 58 recognizable for receiving the bendable sheet metal tongues 61 in the axial contact surface 102 are arranged.

The two cassette parts 51 . 52 are in 7 shown as individual parts. It can be seen that the two cassette parts 51 . 52 at the respective webs 54 first form elements 55 and second form elements 56 have, which are designed complementary to each other. When assembling the two cassette parts 51 . 52 act as provided here as pins and holes first form elements 55 and second form elements 56 so together that the two cassette parts 51 . 52 can be mounted only in a certain angular position with respect to each other. This ensures that the at each angular positions in the cassette parts 51 . 52 recorded planetary roles 20 are arranged at the intended angular positions, so preferably through the cassette parts 51 . 52 realized axial offsets of planetary rolls 20 are executed at the intended angular positions.

8th shows an actuator according to the invention, which comprises the Planetenwälzgewindetrieb. In addition, this actuator has a carrier housing 110 on, in which the Planetenwälzgewindetrieb is arranged, as well as electronics 120 or a control unit with plug connection. Furthermore, in this carrier housing 110 an electric motor 150 arranged, which has a stator 151 as well as the rotor 90 includes. For axial support of the Planetenwälzgewindetriebes on the carrier housing 110 is a sleeve on one axial side 140 arranged.

With the Planetenwälzgewindetrieb proposed here, a device for actuating a clutch is provided, which can be manufactured and assembled in a simple and time-saving manner.

LIST OF REFERENCE NUMBERS

1

Planetenwälzgewindetrieb

10

screw

11

Longitudinal axis of the threaded spindle

12

Torque support

20

planetary roller

21

cylindrical heel

22

circumferential groove

23

journal

30

Planetary roller carrier

31

first hollow cylinder

32

second hollow cylinder

33

Front side of the second hollow cylinder

34

neckline

35

axial boundary wall

40

rotary bearings

41

inner ring

42

outer ring

43

rolling elements

50

cassette

51

First cassette part

52

Second cassette part

53

location hole

54

web

55

first form element

56

second form element

57

third form element

58

recess

59

head Start

60

fourth form element

61

bendable metal tongue

62

recess

63

friction

80

friction surface

81

first form fit

82

second form fit

90

rotor

91

centering

92

Centering surface for rotor

93

axial contact surface

100

Planet storage area

101

Bore for spindle passage

102

axial contact surface

110

support housing

120

electronics

140

shell

150

electric motor

151

stator

Claims (9)

Planetenwälzgewindetrieb (1), in particular as part of an actuator of a disengagement system for a clutch device of a motor vehicle, comprising a threaded spindle (10) and a plurality of the threaded spindle (10) mechanically engaged, about their own longitudinal axis rotatably arranged planetary rollers (20), respectively a cylindrical shoulder (21) in which a plurality of circumferential grooves (22) form a structure which meshes with the thread of the threaded spindle (10), wherein the Planetenwälzgewindetrieb 1 further comprises a planetary roller carrier 30 which supports the planetary rollers 20 at least in the axial direction and Furthermore, the Planetenwälzgewindetrieb 1 has a rotary bearing 40, the inner ring 41 is fixedly connected to the planetary roller carrier 30, characterized in that the Planetenwälzgewindetrieb (1) further comprises an at least two-part cassette (50), which serves for angular position accurate recording of the planetary rollers (20) and d ie axially supported by the planetary roller carrier (30), wherein a cassette part (51) and a second cassette part (52) together form the cassette (50). Planetenwälzgewindetrieb after Claim 1 , characterized in that the cassette parts (51,52) are identical. Planetenwälzgewindetrieb according to at least one of Claims 1 and 2 , characterized in that a first cassette part (51) has a first mold element (55) and a second cassette part (52) has a second mold element (56), wherein the first mold element (55) and the second mold element (56) with respect to their shape and size are designed to be complementary, so that in mechanical operative connection between the two form elements (55,56), the two cassette parts (51,52) are positioned defined in terms of their angular position with respect to each other. Planetenwälzgewindetrieb after Claim 3 , characterized in that a friction element (63) for axially supporting a respective planetary roller (20) is arranged on at least one of the cassette parts (51,52). Planetenwälzgewindetrieb after Claim 3 or 4 , characterized in that at least one of the cassette parts (51, 52) has at least one third mold element (57) and the planetary roller carrier (30) at least one fourth mold element (60), wherein the third mold element (57) and the fourth mold element (60) are configured complementary to each other in their shape and size, that in a mechanical operative connection between the third mold element (57) and the fourth mold element (60) a rotational relative movement of the respective cassette part (51,52) in relation to the planetary roller carrier (30) is blocked , Planetenwälzgewindetrieb after Claim 5 , characterized in that the fourth shaped element (60) is a bendable sheet metal tongue (61) which engages in the bent state in the complementarily configured third form element (57) in the form of a recess (58) of a cassette part (51,52). Method for producing a planetary roller screw drive according to one of the Claims 5 and 6 in which planetary rollers (20) are received in cassette parts (51, 52) and the cassette parts (51, 52) with the planetary rollers (20) are inserted as a cassette (50) in an interior formed by a planetary roller carrier (30), and then at least one third form element (57) of one of the cassette parts (51, 52), designed in particular as a recess (58), and at least one fourth form element (60) of the planetary roller carrier (30), in particular as a bendable metal tongue (61), into a mechanical one Active connection are brought together, in particular by bending the bendable sheet metal tongue (61), so that a rotational relative movement of the respective cassette part (51,52) in relation to the planetary roller carrier (30) is blocked. An actuator comprising a planetary roller screw drive (1) according to any one of Claims 1 - 6 and a rotary drive device mechanically coupled to the planetary roller screw drive (1) for driving an element of the planetary roller screw drive for the purpose of realizing a translatory movement. Release system for a coupling device of a motor vehicle, comprising the actuator according to Claim 8 and an interface for transmitting a generated translational movement to the coupling device.

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