ELECTRICALLY CONTROLLABLE DRIVE ASSEMBLY

Abstract

An electrically controllable drive assembly including an electric motor having a rotor capable of being driven to execute a rotational movement, a motor shaft connected in rotationally fixed fashion to the rotor, and a signal transmitter of a sensor device for the electronic acquisition and evaluation of the angle of rotation of the motor shaft. The signal transmitter is indirectly anchored on the motor shaft via a holding element. The holding element is a hollow cylinder that has an open first end with which the holding element is fastened on the motor shaft and a second end, situated facing away from the motor shaft, and at least one holding element region that extends into the open cross-section of the holding element.

Claims

1-9. (canceled)

10. An electrically controllable drive assembly, comprising: an electronically commuted electric motor, including: a rotor capable of being driven to execute a rotational movement; a motor shaft connected in rotationally fixed fashion to the rotor; a signal transmitter, situated on the motor shaft, of a sensor device configured for electronic acquisition and evaluation of an angle of rotation of the motor shaft; a holding element; and a magnetic element situated on the holding element; wherein the holding element is a hollow cylinder in whose interior the magnetic element is held, the holding element having an open first end with which the holding element with the magnetic element is fastened to the motor shaft and the holding element having a second end, situated facing away from the motor shaft, and having at least one holding element region extending into an open cross-section of the holding element, the magnetic element abutting the holding element region.

11. The drive assembly as recited in claim 10, wherein the motor shaft has, at an end facing the holding element, a segment that is recessed in its outer diameter relative to an outer diameter of the motor shaft, to which segment the signal transmitter is fastened with the open end of the holding element.

12. The drive assembly as recited in claim 11, wherein a transition from the segment of the motor shaft to a circumference of the motor shaft forms a shoulder that the holding element abuts.

13. The drive assembly as recited in claim 10, wherein the magnetic element of the signal transmitter is fastened inside the holding element by a clip element, the clip element having a base that spans a cross-section of the magnetic element, as well as limbs connected to the base that extend on a circumference of the magnetic element in a direction of a longitudinal axis of the motor shaft.

14. The drive assembly as recited in claim 13, wherein the clip element is materially bonded to the holding element by a first weld connection that extends at least in some segments in a circumferential direction of the holding element.

15. The drive assembly as recited in claim 10, wherein the holding element is materially bonded to the motor shaft a second weld connection that extends at least in some segments in a circumferential direction of the holding element.

16. The drive assembly as recited in claim 10, wherein the holding element region of the holding element is fashioned as a transverse web that subdivides the open cross-section of the holding element into a plurality of partial opening cross-sections.

17. The drive assembly as recited in claim 13, wherein the magnetic element of the signal transmitter is fastened between the holding element region of the holding element and the base of the clip element.

18. The drive assembly as recited in claim 10, wherein an extension of the holding element and an extension of the magnetic element, each in a direction of a longitudinal axis L of the motor shaft, are calibrated to one another in such a way that, in a state in which the signal transmitter is mounted on the motor shaft, there is an air gap between an end face of the motor shaft and an end face, facing the motor shaft, of the magnetic element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] An exemplary embodiment of the present invention is illustrated in the figures, and is explained in detail in the following description.

[0016] FIG. 1 shows a drive assembly of the related art.

[0017] FIG. 2 shows detail X of FIG. 1 in an example embodiment according to the present invention.

[0018] FIG. 3 shows the signal transmitter of FIG. 2 without the magnetic element placed therein, in a perspective view.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENT

[0019] FIG. 2 shows detail X of FIG. 1 in an embodiment according to the present invention. Depicted is motor shaft 16 of a drive assembly 10 in the region of its end facing away from a rotor 14 of an electric motor 12 (not shown). According to FIG. 2, this end of motor shaft 16 is equipped with a signal transmitter 24 of a sensor device.

[0020] Signal transmitter 24 includes, in a conventional manner, a magnetic element 26 that is fastened to the end face of motor shaft 16 by a holding element 28 made of magnetically non-conductive material. According to the present invention, holding element 28 is realized as a hollow cylinder, in the interior of which magnetic element 26 is accommodated and is fixedly anchored by a clip element 36. The hollow cylinder has an open first end with which it is pushed onto a segment 38 that is recessed relative to an outer diameter of motor shaft 16. A transition from the circumference of motor shaft 16 to the circumference of segment 38 is shown, as an example, as a right-angled shoulder 40. Holding element 28 abuts this shoulder 40 with a circumferential, radially protruding collar 42 that is fashioned on the open end of this holding element 28. Via segment 28 and its shoulder 40, holding element 28 can be oriented concentrically to a longitudinal axis L of motor shaft 16, and, after its at first positive-fit fastening to motor shaft 16, is in addition materially bonded to this motor shaft 16 by a first weld connection 44. In FIG. 2, this weld connection 44 is formed on the basis of an annular circumferential weld seam; however, alternatively a plurality of successive weld points or weld seam segments could also be provided around the circumference.

[0021] The second end of holding element 28, situated opposite the open first end of holding element 28 and accordingly facing away from motor shaft 16, forms holding element regions 46 that extend into the open cross-section of hollow cylindrical holding element 28, and for example can extend transversely over the entire open cross-section of holding element 28. Magnetic element 26 of signal transmitter 24 axially abuts holding element regions 46, and this magnetic element is accordingly mechanically secured against falling out from the interior of holding element 28.

[0022] A clip element 36 provides an axial fixing of magnetic element 26 inside holding element 28. The clip element is placed into holding element 28 with radial pre-tension, and in addition enters into a positive-fit connection with magnetic element 26.

[0023] Clip element 36 is preferably made of a rectangular plate strip, and is bent in a U shape. Correspondingly, clip element 36 has a base 48 that spans the end face, situated inside holding element 28, of magnetic element 26, and in addition has limbs 50 that are formed at both ends of this base 48 and that stand out at a right angle therefrom in the same direction. Groove-shaped recesses 52 are formed on the circumference of magnetic element 26, which grooves extend in the direction of longitudinal axis L of motor shaft 16, going out from the internal end face of magnetic element 26 up to a point just before its oppositely situated end face. One of the limbs 50 of clip element 36 lies in each recess 52.

[0024] Clip element 36 is materially bonded to holding element 28 by a second weld connection 54. As shown in FIG. 2, the weld seam of this second weld connection 54 is made in circumferentially annular fashion, but alternatively can also be made up of a plurality of weld seam segments that succeed one another in the circumferential direction, or of a plurality of weld points. Thus, magnetic element 26 of signal transmitter 24 is held between holding element region 46, which extends into the open cross-section of hollow cylindrical holding element 28, and clip element 36.

[0025] Between the end face of magnetic element 26, situated inside holding element 28, and a facing end face of motor shaft 16, there is an axial distance and therefore an air gap 56 that at least largely excludes an influencing of the magnetic flux of magnetic element 26 by motor shaft 16.

[0026] FIG. 2 shows the described holding element 28 again, in a perspective representation. Corresponding components or parts of components are provided with the same reference characters in FIGS. 2 and 3, for simplicity. However, in FIG. 3 the magnetic element of signal transmitter 24 is not shown, in order to better illustrate the design of holding element 28 and of clip element 36.

[0027] In this exemplary embodiment, holding element region 46, extending into the open cross-section of holding element 28, is realized as a transverse web that extends over the entire opening cross-section of holding element 28, and divides this opening cross-section into two partial opening cross-sections 58 separate from one another. In principle, it is possible to provide a plurality of such transverse webs and to subdivide the opening cross-section of holding element 28 into further partial opening cross-sections.

[0028] Of course, modifications of or supplements to the described exemplary embodiment are possible without departing from the basic idea of the present invention according to Claim 1, as explained above.