TENSIONING MODULE FOR AN ELECTROMECHANICAL WHEEL BRAKE AND ELECTROMECHANICAL BRAKE DEVICE

1 . A tensioning module for an electromechanical brake device for a motor vehicle comprising

a ball screw drive;

a piston; and

an axial bearing;

wherein the ball screw drive comprises a spindle and a nut;

wherein the spindle comprises a threaded portion and a drive portion; and

wherein the threaded portion and the drive portion are produced as separate components and are connected to one another fixedly for conjoint rotation.

2 . The tensioning module as claimed in claim 1 , wherein the spindle is supported by the axial bearing in the housing.

3 . The tensioning module as claimed in claim 1 , further comprising a stop bearing washer, wherein the stop bearing washer is arranged at an axial end of a radial widening of the spindle, and wherein the axial bearing is arranged on the opposite side of the stop bearing washer to the piston.

4 . The tensioning module as claimed in claim 3 , wherein the stop bearing washer is arranged at a transition between the threaded portion and the drive portion.

5 . The tensioning module as claimed in claim 1 , wherein the stop bearing washer and the drive portion are formed as a one-piece, monolithic component.

6 . The tensioning module as claimed in claim 1 , wherein the threaded portion and the drive portion of the spindle are positively connected to one another, wherein one of: the threaded portion comprises an internal spline system on its drive-side region and the drive portion comprises an external spline system on its piston-side region.

7 . The tensioning module as claimed in claim 1 , wherein the threaded portion and the drive portion of the spindle are connected to one another in a non-positive manner.

8 . The tensioning module as claimed in the preceding claim 1 , wherein the threaded portion and the drive portion of the spindle are connected to one another in an integrally bonded manner.

9 . The tensioning module as claimed in claim 1 , wherein the stop bearing washer comprises an internal spline system.

10 . The tensioning module as claimed in claim 9 , wherein one of: the internal spline system of the threaded portion on the one hand and the external spline system of the drive portion and the stop bearing washer are of precisely mating design and in the mounted position are in an operative relationship to one another via the spline system.

11 . The tensioning module as claimed in claim 10 , wherein a press fit is provided between the internal spline system of the threaded portion on the one hand and the external spline system of the drive portion and/or the stop bearing washer.

12 . The tensioning module as claimed in the preceding claim 1 , wherein the drive portion has a smaller outside diameter than the threaded portion, so that an annular stop is formed which provides a piston-side stop surface for the stop bearing washer.

13 . The tensioning module as claimed in the preceding claim 1 , wherein the following relationship applies to the outside diameter D G of the threaded portion of the spindle in comparison with the outside diameter D A of the drive portion of the spindle: D G >1.3*D A , preferably D G >1.5*D A , particularly preferably D G >1.7*D A .

14 . The tensioning module as claimed in the preceding claim 1 , wherein a positive locking securing element is provided for antirotation safeguard of the ball screw drive.

15 . The tensioning module as claimed in the preceding claim 1 , wherein an antirotation safeguard element is provided which is preferably annular.

16 . The tensioning module as claimed in the preceding claim 1 , wherein the antirotation safeguard element comprises a radially projecting attachment which is received by a recess of the piston.

17 . An electromechanical brake device, preferably an electromechanically actuable disk brake comprising:

a tensioning module;

a ball screw drive;

a piston; and

an axial bearing;

wherein the ball screw drive comprises a spindle and a nut;

wherein the spindle comprises a threaded portion and a drive portion; and

wherein the threaded portion and the drive portion are produced as separate components and are connected to one another fixedly for conjoint rotation; and

an electric motor connected to the spindle for driving the spindle.

18 . The electromechanical brake device as claimed in claim 17 , wherein the electromechanical brake device is on a vehicle.