DE102020120965A1 - planetary screw drive - Google Patents

Abstract

Planetary roller screw drive (1), at least comprising• a threaded spindle (2) with an axis of rotation (4) extending along an axial direction (3),• a plurality of screws which are mechanically engaged with the threaded spindle (2) and each have their own longitudinal axis ( 5) rotatably arranged planetary rollers (6), each having a cylindrical shoulder (7) on which several circumferential grooves (8) form a structure that meshes with a thread (9) of the threaded spindle (2),• a planetary roller carrier (10) , which supports the planetary rollers (5) at least in relation to the axial direction (3), with a first contact surface (11) and• a housing part (12) with a second contact surface (13); wherein when the planetary roller carrier (10) rotates about the threaded spindle (2), the threaded spindle (2) can be displaced relative to the planetary roller carrier (10) along the axial direction (3).

Description

The present invention relates to a planetary screw drive, in particular as part of an actuator of a release system for a clutch device of a motor vehicle.

In order to actuate clutches, a translatory path must usually be covered in order to separate clutch halves from one another or to bring them into engagement with one another. For this purpose, actuating devices are required, which are also called actuators or actuators, and with which a required force can be generated over a corresponding path. For this purpose, there are actuators that 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 screw (spindle) drives. A planetary rolling thread comprises at least one threaded spindle with an axis of rotation extending along an axial direction, a plurality of planetary rollers that mechanically engage with the threaded spindle and are each arranged to be rotatable about their own longitudinal axis, each of which has a cylindrical shoulder on which several circumferential grooves form a structure form, which meshes with a thread of the threaded spindle, a planetary roller carrier, which supports the planetary rollers at least with respect to the axial direction, and a housing part in which the planetary roller carrier is arranged. With a rotation z. B. the planetary roller carrier to the threaded spindle or the axis of rotation, the threaded spindle is displaced relative to the planetary roller carrier along an axial direction.

The housing part can, for. B. be connected to a rotor of an electric drive, so that the housing part and thus the planetary roller carrier is rotated relative to the threaded spindle by rotation of the rotor.

The planetary roller screw drive can have an at least two-part cassette as a planetary roller carrier, which is used to accommodate the planetary rollers with an exact angular position and which is supported axially by the housing part. For the defined positioning of the cassette parts, the parts of the cassette can have shaped elements, so that when there is a mechanical operative connection between the shaped elements, the two cassette parts are positioned in a defined manner with regard to their angular position in relation to one another.

The planetary roller carrier or at least one of the cassette parts can have at least one further shaped element which interacts with a correspondingly designed shaped element of the housing part, so that when there is a mechanical operative connection between the shaped elements, a relative rotational movement of the planetary roller carrier or the respective cassette part in relation to the housing part is blocked. This connection is used to transmit torque between the housing part and the planetary roller carrier.

In the DE 10 2017 125 149 A1 this shaped element between the cassette part and the housing part is a bendable sheet metal tongue on the housing part, which in the bent state engages in a complementary shaped shaped element in the form of a recess in a cassette part.

In order to form the shaped elements, the affected components sometimes have to be mechanically processed in a complex manner. To ensure dimensional accuracy, it may be necessary for this processing to take place only after the material has increased in hardness (e.g. as a result of heat treatment).

Proceeding from this, the object of the present invention is to at least partially overcome the problems known from the prior art and in particular to specify a planetary screw drive in which reliable torque transmission between the components can be realized and which can be produced inexpensively.

This object is achieved with a planetary screw drive according to the features of independent claim 1. Further advantageous refinements of the invention are specified in the dependent claims. The features listed individually in the dependent claims can be combined with one another in a technologically meaningful manner and can define further refinements of the invention. In addition, the features specified in the claims are specified and explained in more detail in the description, with further preferred configurations of the invention being presented.

• • eine Gewindespindel mit einer sich entlang einer axialen Richtung erstreckenden Drehachse,
• • eine Mehrzahl von mit der Gewindespindel mechanisch in Eingriff stehenden, um jeweils eine eigene Längsachse rotierbar angeordnete, Planetenrollen, die jeweils einen zylindrischen Absatz aufweisen, an dem mehrere Umfangsrillen eine Struktur ausbilden, die mit einem Gewinde der Gewindespindel kämmt,
• • einen Planetenrollenträger, der die Planetenrollen zumindest gegenüber der axialen Richtung abstützt, mit einer ersten Kontaktfläche sowie
• • ein Gehäuseteil mit einer zweiten Kontaktfläche.

A planetary screw drive is proposed, in particular as a component of an actuator of a release system for a clutch device of a motor vehicle. The planetary screw drive includes at least

• • a threaded spindle with an axis of rotation extending along an axial direction,
• • a plurality of mechanically engaged with the threaded spindle, each arranged to be rotatable about its own longitudinal axis, Planetary rollers, each of which has a cylindrical shoulder on which several circumferential grooves form a structure that meshes with a thread on the threaded spindle,
• • a planetary roller carrier, which supports the planetary rollers at least in relation to the axial direction, with a first contact surface and
• • a housing part with a second contact surface.

When the planetary roller carrier rotates about the threaded spindle, the threaded spindle can be displaced in an axial direction relative to the planetary roller carrier. Via the contact surfaces, the planetary roller carrier and the housing part form a first connection that is form-fitting relative to a circumferential direction. At least one of the contact surfaces has a surface structure through which the other contact surface can be deformed at least partially when the planetary screw drive is assembled to form the first connection.

The threaded spindle is in particular (only) rotatable relative to the planetary roller carrier. When rotating relative to the planetary roller carrier, the threaded spindle can be displaced relative to the planetary roller carrier along the axial direction. The threaded spindle has a thread so that the threaded spindle can be successively displaced as a function of a thread pitch as a result of the meshing arrangement with the planetary rollers. The structure of the planetary rollers rolls on the thread of the threaded spindle. Each planetary roller has a longitudinal axis, which is arranged in particular parallel to the axis of rotation, and is arranged on the planetary roller carrier such that it can rotate about this longitudinal axis.

The housing part can, for. B. be connected to a rotor of an electric drive, so that the housing part and thus the planetary roller carrier and the associated planetary rollers relative to the threaded spindle and rotated about the axis of rotation by rotation of the rotor.

It is now proposed here that the planetary roller carrier and the housing part form a first connection that is form-fitting relative to a circumferential direction via the contact surfaces. To form the first connection, in particular only one of the contact surfaces has a surface structure which engages in the contact surface of the other component during assembly of the planetary roller carrier and housing part and forms a complementary surface structure there. The deformation of the other contact surface by the surface structure includes in particular a displacement of material.

In particular, this type of first connection means that the planetary roller carrier and the housing part do not have to be aligned with one another, at least with respect to a circumferential direction, before assembly. Furthermore, a torque acting in the circumferential direction can be transmitted without play (relative to the circumferential direction) by the first connection designed in this way. Furthermore, the torque, distributed uniformly along the circumferential direction, can be transmitted between the planetary roller carrier and the housing part.

The surface structure can B. be made by a knurling process. When knurling, a round workpiece is pressed against a round tool that has the surface structure and rolled over one another so that both rotate. The surface structure of the tool is transferred to the workpiece. So e.g. B. elevations on the surface of the tool are pressed into the surface of the workpiece.

In particular, at least one of the contact surfaces is formed by a plastic material.

In particular, the other (or at least one) contact surface is formed by a metallic material, e.g. B. by a ferrous material, preferably by a steel.

In particular, the contact surface with the higher strength has the surface structure. The surface structure can thus be used to deform the other contact surface during assembly of the components.

In particular, the planetary roller carrier and the housing part are made of materials whose coefficients of thermal expansion [1/Kelvin] differ from one another by at most 10%, preferably by at most 5%. In this way, a low backlash (relative to the circumferential direction) and a constant pressure between the housing part and the planetary roller carrier (eg relative to a radial direction) can be ensured during operation of the planetary roller screw drive.

In particular, the contact surfaces are arranged concentrically to one another, with a largest outer diameter of the first contact surface being larger than a smallest inner diameter of the second contact surface. The contact surfaces thus overlap in the radial direction, so that a surface structure on one contact surface can be used to deform or reshape the other contact surface.

In particular, a first connection can be realized in the manner of a toothing or a splined toothing.

In particular, the planetary roller carrier is designed in several parts (like a cassette) and comprises at least a first part with first receptacles and a second part with second receptacles for the planetary rollers, with the first part and the second part forming a second connection that is form-fitting relative to the circumferential direction. Each planetary roller extends in particular starting from a first end along the longitudinal axis towards a second end. Each first end is located in a first receptacle and each second end is located in a second receptacle.

The planetary rollers can be identical or different from each other. Particularly in the embodiment with planetary rollers of the same construction, it is provided that at least one of the (cassette) parts for each planetary roller to be arranged therein has a receptacle with a shoulder of different axial extent. This shoulder is used for the axially offset arrangement of a respective planetary roller that is supported on it in relation to the axial direction, in order to ensure that a respective planetary roller has a defined position in relation to the axial direction for clean engagement in the thread of the threaded spindle. The axial position here refers to the axis of rotation of the centrally located threaded spindle.

Furthermore, a friction element for axially supporting a respective planetary roller can be arranged on at least one of the (cassette) parts or in at least one of the receptacles. This friction element, which is also referred to as a friction plate, is arranged, for example, in the receptacle or on a bearing journal of a planetary roller or else on a front shoulder of the planetary roller. The material pairing of planetary roller and friction element should preferably have a coefficient of friction μ ≤ 0.15. As a result, wear caused by friction, which occurs when axial forces are transmitted to or from the planetary rollers for the planetary roller carrier, can be reduced in a simple manner.

In particular, only one of the parts forms the form-fitting first connection with the housing part.

Alternatively, both parts each form a form-fitting first connection with the housing part.

1. a) Bereitstellen zumindest des Planetenrollenträgers und der Planetenrollen;
2. b) Bereitstellen des Gehäuseteils;
3. c) Zusammenbau des Planetenrollenträgers und des Gehäuseteils und Ausbilden der ersten Verbindung durch zumindest teilweises Verformen der einen Kontaktfläche durch die Oberflächenstruktur der anderen Kontaktfläche.

A method for producing the planetary screw drive described is also proposed, at least having the following steps:

1. a) providing at least the planetary roller carrier and the planetary rollers;
2. b) providing the housing part;
3. c) Assembling the planetary roller carrier and the housing part and forming the first connection by at least partially deforming one contact surface through the surface structure of the other contact surface.

Steps a) and b) can in particular be carried out in different sequences. The threaded spindle can be provided before step c), possibly together with the planetary roller carrier. Steps a) to c) take place in particular in the specified order.

In particular, the contact surfaces are arranged concentrically to one another, with a largest outer diameter of the first contact surface being larger than a smallest inner diameter of the second contact surface. The contact surfaces thus overlap in the radial direction, so that a surface structure on one contact surface can be used to deform or reshape the other contact surface.

The assembly takes place in particular by pushing the planetary roller carrier into the housing part along the axial direction.

In particular, a first connection can be realized in the manner of a toothing or a splined toothing.

In particular, at least one of the planetary roller carrier and the housing part is at least partially made of a metallic material. In particular, prior to step c), the material is first mechanically processed to form the surface structure and then the material is hardened to increase the hardness of the material.

Furthermore, an actuator is proposed which has the described planetary roller screw drive and a rotary drive device mechanically coupled to the planetary roller screw drive for driving an element of the planetary roller screw drive for the purpose of realizing a translatory movement. The actuator according to the invention can also be referred to as a modular clutch actuator (MCA). The translational movement is carried out by an element of the planetary screw drive, such as the threaded spindle, which is supported in a rotationally fixed manner, and used to actuate a clutch device for the purpose of opening or closing. To this Purpose is the planetary roller carrier of the planetary roller screw with a rotor of the drive device, here the housing part, non-rotatably connected, with which the planetary roller carrier can be driven about its central axis of rotation, so that there is a translatory displacement of the threaded spindle.

Furthermore, a release system for a clutch device of a motor vehicle is proposed, which has the actuator described and an interface for transmitting a generated translational movement to the clutch device

The statements on the planetary screw drive can be transferred in particular to the method, the actuator and the release system and vice versa.

The use of indefinite articles (“a”, “an”, “an” and “an”), particularly in the claims and the description reflecting them, is to be understood as such and not as a numeral. Correspondingly introduced terms or components are to be understood in such a way that they are present at least once and in particular can also be present several times.

As a precaution, it should be noted that the numerals used here (“first”, “second”, ...) primarily (only) serve to distinguish between several similar objects, sizes or processes, i.e. in particular no dependency and/or sequence of these objects, sizes or make processes mandatory for each other. Should a dependency and/or order be necessary, this is explicitly stated here or it is obvious to the person skilled in the art when studying the specifically described embodiment. If a component can occur several times (“at least one”), the description of one of these components can apply equally to all or part of the majority of these components, but this is not mandatory.

• 1: eine erste Ausführungsvariante eines bekannten Planetenwälzgewindetriebs in einer Seitenansicht im Schnitt;
• 2: ein Gehäuseteil des Planetenwälzgewindetriebs nach 1 in einer perspektivischen Ansicht;
• 3: einen Planetenrollenträger des Planetenwälzgewindetriebs nach 1 in einer perspektivischen Ansicht;
• 4: eine zweite Ausführungsvariante eines bekannten Planetenwälzgewindetriebs in einer perspektivischen Ansicht in einer Seitenansicht im Schnitt;
• 5: einen Planetenrollenträger des Planetenwälzgewindetriebs nach 4 in einer perspektivischen Ansicht;
• 6: einen Planetenwälzgewindetrieb in einer Seitenansicht im Schnitt;
• 7: einen Planetenrollenträger des Planetenwälzgewindetriebs nach 6 in einer perspektivischen Ansicht im Schnitt;
• 8: den Planetenrollenträger nach 7 in einer Explosionsdarstellung in einer perspektivischen Ansicht im Schnitt;
• 9: ein Gehäuseteil des Planetenwälzgewindetriebs nach 6 in einer perspektivischen Ansicht im Schnitt; und
• 10: ein Teil des mehrteiligen Planetenrollenträgers nach 7 und 8 in einer perspektivischen Ansicht.

The invention and the technical environment are explained in more detail below with reference to the attached figures. It should be pointed out that the invention should not be limited by the exemplary embodiments given. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and findings from the present description. In particular, it should be pointed out that the figures and in particular the proportions shown are only schematic. Show it:

• 1 : a first embodiment variant of a known planetary screw drive in a side view in section;
• 2 : a housing part of the planetary screw drive 1 in a perspective view;
• 3 : a planetary roller carrier of the planetary screw drive 1 in a perspective view;
• 4 : a second embodiment variant of a known planetary screw drive in a perspective view in a side view in section;
• 5 : a planetary roller carrier of the planetary screw drive 4 in a perspective view;
• 6 : a planetary screw drive in a side view in section;
• 7 : a planetary roller carrier of the planetary screw drive 6 in a perspective view in section;
• 8th : the planetary roller carrier 7 in an exploded perspective view in section;
• 9 : a housing part of the planetary screw drive 6 in a perspective view in section; and
• 10 : part of the multi-part planetary roller carrier 7 and 8th in a perspective view.

1 shows a first embodiment of a known planetary screw drive 1 in a side view in section. 2 shows a housing part 12 of the planetary screw drive 1 after 1 in a perspective view. 3 shows a planetary roller carrier 10 of the planetary screw drive 1 after 1 in a perspective view. the 1 until 3 are described together below.

A planetary rolling thread 1 comprises at least one threaded spindle 2 with an axis of rotation 4 extending along an axial direction 3, a plurality of planetary rollers 6 which mechanically engage with the threaded spindle 2 and are each arranged to be rotatable about their own longitudinal axis 5, each of which has a cylindrical shoulder 7 on which a plurality of circumferential grooves 8 form a structure which meshes with a thread 9 of the threaded spindle 2, a planetary roller carrier 10 which supports the planetary rollers 6 at least with respect to the axial direction 3, and a housing part 12 in which the planetary roller carrier 10 is arranged. With a rotation z. B. the planetary roller carrier 10 to the threaded spindle 2 or the Axis of rotation 4, the threaded spindle 2 is displaced relative to the planetary roller carrier 10 along an axial direction 3.

The planetary roller carrier 10 and the housing part 12 are connected via shaped elements in such a way that a first connection 15 is formed which is form-fitting relative to the circumferential direction 14 .

The planetary roller carrier 10 is made in two parts here.

The housing part 12 can, for. B. be connected to a rotor of an electric drive, so that the housing part 12 and thus the planetary roller carrier 10 is rotated relative to the threaded spindle 2 by rotation of the rotor.

4 shows a second embodiment variant of a known planetary screw drive 1 in a perspective view in a side view in section. 5 shows a planetary roller carrier 10 of the planetary screw drive 1 after 4 in a perspective view. the 4 and 5 are described together below. On the remarks on the 1 until 3 is referenced.

In contrast to the first embodiment, the planetary screw drive 1 according to DE 10 2017 125 149 A1 an at least two-part cassette as a planetary roller carrier 10, which serves to accommodate the planetary rollers 6 with precise angular positions and which is supported axially by the housing part 12. For the defined positioning of the cassette parts, the parts 19, 21 of the cassette can have shaped elements, so that when there is a mechanical operative connection between the shaped elements, the two cassette parts are positioned in a defined manner in relation to one another via the second connection 23 in terms of their angular position.

The planetary roller carrier 10 or at least one of the cassette parts can have at least one further shaped element, which interacts with a correspondingly designed shaped element of the housing part 12, so that when there is a mechanical operative connection between the shaped elements, a relative rotational movement of the planetary roller carrier 10 or the respective cassette part in relation to the housing part 12 is blocked. This first connection 15 serves to transmit torque between the housing part 12 and the planetary roller carrier 10. Here this shaped element between the second part 21 of the planetary roller carrier 10 and the housing part 12 is a bendable sheet metal tongue on the housing part 12, which in the bent state becomes a shaped element with a complementary design engages the form of a recess of a cassette part.

6 shows a planetary screw drive 1 in a side view in section. 7 shows a planetary roller carrier 10 of the planetary screw drive 1 after 6 in a perspective view in section. 8th shows the planetary roller carrier 10 7 in an exploded view in a perspective view in section. 9 shows a housing part 12 of the planetary screw drive 1 after 6 in a perspective view in section. 10 shows a part of the multi-part planetary roller carrier 10 after 7 and 8th in a perspective view. the 6 until 10 are described together below. On the remarks on the 1 until 5 is referred to.

The planetary roller screw drive 1 comprises a threaded spindle 2 with an axis of rotation 4 extending along an axial direction 3, a plurality of planetary rollers 6 which mechanically engage with the threaded spindle 2 and are each arranged to be rotatable about their own longitudinal axis 5, each of which has a cylindrical shoulder 7 , on which several circumferential grooves 8 form a structure that meshes with a thread 9 of the threaded spindle 2, a planetary roller carrier 10, which supports the planetary rollers 6 at least with respect to the axial direction 3, with a first contact surface 11, and a housing part 12 with a second contact surface 13 When the planetary roller carrier 10 rotates about the threaded spindle 2 , the threaded spindle 2 can be displaced in relation to the planetary roller carrier 10 along an axial direction 3 . The planetary roller carrier 10 and the housing part 12 form, via the contact surfaces 11, 13, a first connection 15 which is form-fitting relative to a circumferential direction 14. At least one of the contact surfaces 11, 13 has a surface structure 16, through which the other contact surface 13, 11 is at least partially deformable during assembly of the planetary screw drive 1 to form the first connection 15.

When rotating relative to the planetary roller carrier 10, the threaded spindle 1 can be displaced relative to the planetary roller carrier 10 along the axial direction 3. The threaded spindle 2 has a thread 9, so that the threaded spindle 2 can be displaced successively along the axial direction 3 as a result of the meshing arrangement with the planetary rollers 6, depending on a thread pitch. The structure of the planetary rollers 6 rolls on the thread 9 of the threaded spindle 2 . Each planetary roller 6 has a longitudinal axis 5 , which is arranged parallel to the axis of rotation 4 , and is arranged on the planetary roller carrier 10 such that it can rotate about this longitudinal axis 5 .

The housing part 12 can, for. B. be connected to a rotor of an electric drive, so that by rotating the rotor, the housing part 12 and thus the planetary roller carrier 10 and the planetary rollers 6 connected thereto are rotated relative to the threaded spindle 2 and about the axis of rotation 4 .

It is now proposed here that the planetary roller carrier 10 and the housing part 12 form a first connection 15 that is form-fitting relative to a circumferential direction 14 via the contact surfaces 11 , 13 . To form the first connection 15, in particular only one of the contact surfaces 11, 13 has a surface structure 16 which engages in the contact surface 11, 13 of the other component during the assembly of the planetary roller carrier 10 and housing part 12 and forms a complementary surface structure 16 there. The deformation of the other contact surface 13, 11 by the surface structure 16 includes in particular a displacement of material.

This type of first connection 15 makes it possible, in particular, for the planetary roller carrier 10 and the housing part 12 not to have to be aligned with one another, at least with respect to a circumferential direction 14, before assembly. Furthermore, a torque acting in the circumferential direction 14 can be transmitted without play (relative to the circumferential direction 14) by the first connection 15 designed in this way. Furthermore, the torque, distributed uniformly along the circumferential direction 14 , can be transmitted between the planetary roller carrier 10 and the housing part 12 .

The surface structure 16 can, for. B. be produced by a knurling process (see surface structure 9 and 10 ).

The contact surfaces 11, 13 are arranged concentrically to one another, with a largest outer diameter 17 of the first contact surface 11 (see 10 ) is larger than a smallest inner diameter 18 of the second contact surface 13 (see 9 ). The contact surfaces 11, 13 thus overlap in the radial direction 24, so that a surface structure 16 on one contact surface 11, 13 can be used to deform or reshape the other contact surface 13, 11.

In particular, a first connection can be realized in the manner of a tooth system or a spline system (see 9 and 10 ).

In the 9 and 10 it is shown in each case that this surface structure 16 can be formed on each of the components housing part 12 and planet carrier 10 .

It is preferred that the planet carrier 10 is made of a plastic material and has no surface structure 16 prior to assembly. The surface structure 16 is in particular only provided on the housing part 12 and is embossed onto the first contact surface 11 as part of step c) of the method.

The planetary roller carrier 10 is designed in several parts (in the manner of a cassette) and comprises at least a first part 19 with first receptacles 20 and a second part 21 with second receptacles 22 for the planetary rollers 6, the first part 19 and the second part 21 having shaped elements ( compare 4 and 5 ) form a second connection 23 that is form-fitting relative to the circumferential direction 14 . Each planetary roller 6 extends in particular starting from a first end along the longitudinal axis 5 towards a second end. Each first end is positioned in a first receptacle 20 and each second end is positioned in a second receptacle 22 .

The planetary rollers 6 can be identical in construction or different from one another. Particularly in the embodiment with identical planetary rollers 6, at least one of the (cassette) parts 19, 21 for each planetary roller 6 to be arranged therein has a receptacle 20, 22 with a shoulder of different axial extent. This shoulder is used for the axially offset arrangement of a respective planetary roller 6, which is supported on it in relation to the axial direction 3, in order to ensure that a respective planetary roller 6 has a defined position in relation to the axial direction 3 for clean engagement in the thread 9 of the threaded spindle 2. The axial position here refers to the axis of rotation 4 of the centrally located threaded spindle 2.

Furthermore, a friction element for the axial support of a respective planetary roller 6 can be arranged on at least one of the (cassette) parts 19, 21 or in at least one of the receptacles 20, 22. This friction element, which is also referred to as a friction plate, is arranged, for example, in the receptacle 20, 22 or on a bearing journal of a planetary roller 6 or also on a front shoulder of the planetary roller 6.

According to 6 , 7 , 8th and 9 it can be seen that both parts 19, 21 each form a form-fitting first connection 15 with the housing part 12.

The planetary roller screw drive 1 is assembled by pushing the planetary roller carrier 10 or both parts 19, 21 into the housing part 12 along the axial direction 4.

A first connection 15 can thus be realized in the manner of a tooth system or a spline system (see 9 and 10 .

Reference List

1

planetary screw drive

2

lead screw

3

axial direction

4

axis of rotation

5

longitudinal axis

6

planetary roll

7

paragraph

8th

circumferential groove

9

thread

10

planetary roller carrier

11

first contact surface

12

housing part

13

second contact surface

14

circumferential direction

15

first connection

16

surface texture

17

largest outer diameter

18

smallest inside diameter

19

first part

20

first shot

21

second part

22

second shot

23

second connection

24

radial direction

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was 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.

Patent Literature Cited

• DE 102017125149 A1 [0007, 0047]

Claims (10)

Planetary screw drive (1), at least comprehensive • a threaded spindle (2) with an axis of rotation (4) extending along an axial direction (3), • a plurality of planetary rollers (6) which are mechanically engaged with the threaded spindle (2) and are each arranged to be rotatable about their own longitudinal axis (5), each having a cylindrical shoulder (7) on which several circumferential grooves (8) form a structure which meshes with a thread (9) of the threaded spindle (2), • a planetary roller carrier (10), which supports the planetary rollers (5) at least with respect to the axial direction (3), with a first contact surface (11) and • a housing part (12) with a second contact surface (13); wherein when the planetary roller carrier (10) rotates about the threaded spindle (2), the threaded spindle (2) can be displaced relative to the planetary roller carrier (10) along the axial direction (3); wherein the planetary roller carrier (10) and the housing part (12) via the contact surfaces (11, 13) form a first connection (15) which is form-fitting relative to a circumferential direction (14); at least one of the contact surfaces (11, 13) having a surface structure (16) through which the other contact surface (13, 11) can be deformed at least partially when the planetary screw drive (1) is assembled to form the first connection (15). Planetary screw drive (1) after claim 1 , wherein at least one of the contact surfaces (11, 13) is formed by a plastic material. Planetary screw drive (1) after claim 2 , wherein the other contact surface (13, 11) is formed by a metallic material. Planetary screw drive (1) according to one of the preceding claims, wherein the planetary roller carrier (10) and the housing part (12) are made of materials whose coefficients of thermal expansion differ from one another by at most 10%. Planetary screw drive (1) according to one of the preceding claims, wherein the contact surfaces (11, 13) are arranged concentrically to one another, with a largest outer diameter (17) of the first contact surface (11) being larger than a smallest inner diameter (18) of the second contact surface (13 ). Planetary screw drive (1) according to one of the preceding claims, wherein the planetary roller carrier (10) is designed in several parts and at least a first part (19) with first receptacles (20) and a second part (21) with second receptacles (22) for the planetary rollers ( 6), wherein the first part (19) and the second part (21) form a second connection (23) that is form-fitting in relation to the circumferential direction (14). Planetary screw drive (1) after claim 6 , wherein only one of the parts (19, 21) forms the form-fitting first connection (15) with the housing part (12). Planetary screw drive (1) after claim 6 , Both parts (19, 21) with the housing part (12) each form a form-fitting first connection (15). Method for producing a planetary screw drive (1) according to one of the preceding claims, at least having the following steps: a) providing at least the planetary roller carrier (10) and the planetary rollers (6); b) providing the housing part (12); c) Assembling the planetary roller carrier (10) and the housing part (12) and forming the first connection (15) by at least partially deforming the one contact surface (11, 13) through the surface structure (16) of the other contact surface (13, 11). procedure after claim 9 wherein at least one of the planetary roller carrier (10) and the housing part (12) is at least partially made of a metallic material; before step c), the material is first mechanically processed to form the surface structure (16) and then the material is hardened to increase the hardness of the material.

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