WO2010066492A2

WO2010066492A2 - Stator in an electric motor

Info

Publication number: WO2010066492A2
Application number: PCT/EP2009/063537
Authority: WO
Inventors: Johannes Duerr; Stefan Keil; Wolfgang Hilgers; Adolf Dillmann
Original assignee: Robert Bosch Gmbh
Priority date: 2008-12-11
Filing date: 2009-10-16
Publication date: 2010-06-17
Also published as: DE102008054523A1; WO2010066492A3; EP2377229A2

Abstract

The invention relates to a stator in an electric motor having a plurality of individual stator elements that form support teeth and are arranged around the periphery of said stator. Each support tooth is provided with a wound coil and detents for mechanically interconnecting the support teeth are arranged on said support teeth.

Description

description

title

[STATOR IN AN E LEOT ROMOTO Rl

The invention relates to a stator in an electric motor, in particular in a control or drive motor in motor vehicles.

State of the art

In US 2006/0091759, a permanent-magnet internal rotor

Described DC motor whose stator comprises a fixed stator in a housing, which is composed of a plurality of individual lamellae. The lamellae are arranged axially one behind the other and support a stator winding, via which a magnetic field is generated, which interacts with permanent magnets on the rotor shaft. The lamellae form a coherent package and are held together axially by suitable clamping means.

Disclosure of the invention

The invention is based on the object of structurally simple to construct a stator in an electric motor.

This object is achieved according to the invention with the features of claim 1. The dependent claims indicate expedient developments.

The stator according to the invention is used in an electric motor, for example in a control or drive motor in motor vehicles. Applications may also be considered as a starter motor, as a steering motor or for actuating an auxiliary unit such as, for example, a windshield wiper, a window sash. bers or a seat adjustment motor. The electric motor comprises the stator according to the invention and a rotor shaft which is rotatably mounted in the stator.

The stator has a plurality of individual stator elements distributed over the circumference, which each form carrier teeth, each carrier tooth being provided with a wound coil. The various coils on the carrier teeth are at least partially electrically connected to each other and are electrically energized to generate a magnetic field.

For a structurally simple construction latching elements for mechanical connection of the support teeth are arranged with each other on the support teeth. The locking elements make it possible to attach two support teeth to each other, so that a continuous chain can be assembled in the direction of a plurality of contiguous support teeth to form the stator. It may be expedient to carry out the connection between the support teeth exclusively by mechanical means and by means of the locking elements, so that beyond the locking elements no further connecting elements between the support teeth or a support tooth and another component are required. The locking elements are in particular made in one piece with the carrier teeth, so that no external, additional

Components needed for the realization of the connection.

According to a preferred embodiment, it is provided that the latching elements are arranged adjacent to the radial outer side of the carrier teeth. In addition, it is expedient to position the latching elements in the circumferential direction on the outside of each support tooth, so that the latching elements can be brought directly to each other in latching position at different, directly adjacent support teeth. The positioning of the latching elements on the radial outer side and in the circumferential direction on the outside has the advantage that a continuous stator ring can be formed from the carrier teeth without hindrance by the latching elements.

According to a further advantageous embodiment, the latching elements are integrally formed with a plastic casing which is part of the carrier teeth. According to a preferred embodiment, the carrier teeth on an iron core and the plastic casing is sprayed onto the iron core, so that the Iron core is at least partially covered by the plastic sheath. The locking elements are preferably made in one piece with the plastic casing and are also produced by injection molding.

According to an alternative embodiment, it is also possible to form the locking elements separately from the plastic sheath. For example, the plastic sheath exists only in the region of the coil winding in order to achieve an electrical separation of coil and iron core. In addition to this plastic casing, the latching elements can be injection-molded as a plastic part directly on the iron core of the carrier tooth.

According to yet another embodiment, the latching elements are formed as metal components, which are connected to the main body of the carrier tooth.

In order to be able to produce the latching connection between latching elements involved in a simple manner, it may be expedient that at least one of the latching elements is designed to be elastically deformable. For example, a wall section carrying a latching element can have a reduced cross-section, so that this latching element can execute an at least slight bend over the reduced wall cross-section. However, it is also possible to provide a latching recess, which is part of a latching element, with a bendable wall, so that a latching projection, which forms the second latching element, can be buttoned into the latching recess by slight bending of the wall.

According to another expedient embodiment, it is provided that the carrier teeth are arranged at an angle relative to the stator longitudinal axis, such that the tooth longitudinal axis of each carrier tooth with the stator longitudinal axis - which coincides with the rotor axis - forms an angle. This angle can be, for example, up to 30 °, but preferably about 10 ° or slightly underneath, with basically all intermediate angle values come into consideration. About the angled arrangement of the support teeth helical teeth is achieved, with the result that a smoothing or homogenization in the output torque curve is achieved. The electrical connection between adjacent coils in the stator ring and the electrical power supply is preferably carried out by means of a contact ring, which is a carrier of electrical contact elements, via which the coil wire of a coil to be electrically connected to the coil wire of another coil. The contact ring allows in a simple mechanical way the electrical connection to each coil, so that can be dispensed with a soldering or welding technology.

In principle, it is sufficient to realize the latching between adjacent carrier teeth via a pair of latching elements per carrier tooth pair, wherein the latching elements are preferably arranged adjacent to an axial end face of the carrier teeth, in particular adjacent to the free coil wire ends, via which the coils are electrically connected to the contact ring. However, the locking elements can also be arranged on the opposite end face or axially in the middle of the carrier teeth. In addition, it is also possible to provide per carrier tooth a plurality of locking elements at different axial positions, which cooperate with complementary formed locking elements of another carrier tooth.

So that each support tooth with adjacent support teeth on both sides in

Detent position can occur, per carrier tooth at least two individual locking elements are provided as part of a respective latching connection to the adjacent support tooth left and right.

Further advantages and expedient embodiments can be taken from the further claims, the description of the figures and the drawings. Show it:

1 shows an exploded view of the components of an electric motor, wherein the stator is composed of individual carrier teeth, each with a coil, which by means of a contact ring and arranged thereon

Insulation displacement terminals are electrically connected to each other, as well as arranged on an end side, the output side bearing plate, which is directly connected to the motor housing of the electric motor, 2 shows a detail of an electronic assembly which is seated on a further bearing plate, which is arranged on the opposite end face of the electric motor,

3 is a side view of the stator of the electric motor, which consists of a plurality of circumferentially distributed carrier teeth, which are arranged at an angle relative to the stator longitudinal axis,

4a is a perspective detail view of a carrier tooth with a coil,

4b is a side view of a carrier tooth with coil,

5 shows a section through a carrier tooth with coil,

6 is a plan view of a carrier tooth with coil, wherein the wire ends of the coil winding are each guided over an introduced into the front side of the carrier tooth receiving pocket,

7 is a perspective view of the mechanical connection between adjacent carrier teeth realized via clips;

8 is an enlarged view of the realized via a clip connection between two immediately adjacent support teeth,

9 is a perspective view of a contact ring, consisting of a plurality of individual rings, each having a plurality of insulation displacement terminals, which form contact elements,

10 shows the contact ring with the individual rings in exploded view,

1 1 is a perspective view from above of the mounted electric motor,

12 shows a section through the electric motor with a magnet inserted into the end face of the rotor shaft as part of a rotor position sensor system.

In the figures, the same components are provided with the same reference numerals. In Fig. 1, the components of an electric motor 1 are shown in exploded view. The electric motor 1 is designed as an internal rotor motor and comprises a rotor shaft 2, which is the carrier of a rotor stack 3. The rotor shaft 2 including the rotor core 3 is in the assembled state in a stator 4, which is a carrier of several distributed over the circumference coils, which is electrically contacted and supplied with power via an axially arranged on the stator contact ring 5 and disposed thereon insulation displacement terminals 6 become. On the output side of the electric motor there is a first bearing plate 7 (A bearing plate), which receives a bearing part 8 for the rotor shaft 2. The A-bearing plate

7 is fixedly connected to a motor housing 10 which receives the stator 4 including the rotor shaft 2.

On the A-bearing plate 7 axially opposite end face is another bearing part 9 for supporting the rotor shaft 2. The bearing part 9 is in the assembled state in a further bearing plate 1 1 (B-bearing plate, shown in Fig. 2) added. The bearing plate 1 1 is also a carrier of electronic components 12, via which the control or regulation of the electric motor 1 takes place.

The A-bearing plate 7 and the B-bearing plate 1 1 grasp the motor housing 10 at opposite axial end faces and are directly or directly connected to the motor housing 10. Appropriately, it is an exclusive connection of each bearing plate 7, 1 1 with the motor housing 10, so that beyond this connection, no further connection measures such as tie rods between the bearing plates or the like are required. The connection is made by welding between the end face of the motor housing 10 and the bearing plates 7 and 1 1 or by shrinking. In any case, a tight connection is achieved, so that can be dispensed with the use of additional sealing elements between the bearing plates and the motor housing. Another advantage lies in the improved stiffness that comes on

Reason for the direct connection of bearing plates and motor housing is increased. The improved stiffness also has a positive influence on the torque curve. Furthermore, the heat dissipation is improved. In addition, a modular system is realized in this way, in which differently long stator or motor housings 10 are used without any other change in the components of the electric motor, depending on the intended application can be. Since the connection between each bearing plate and the motor housing via welding or shrinking or the like, and not via tie rods, no further adaptation measures are required even with different long motor housings.

The contact ring 5 with the cutting elements 6 designed as contact elements is suitably held as well as the bearing part 9 of the B-bearing plate 1 1.

As shown in FIG. 3, the stator 4 is made of a plurality of over the

Distributed circumferentially arranged, individual carrier teeth 13, each carrier a coil 17. The carrier teeth 13 close with the stator longitudinal axis 14, which also forms the longitudinal axis of the electric motor, (FIG. 1), an angle α. In Fig. 3 a tooth longitudinal axis 15 is entered through a support tooth 13, wherein the side edges of each support tooth 13 extend parallel to the tooth longitudinal axis 15. The angle α, under which each support tooth 13 is aligned at an angle relative to the stator longitudinal axis 14, in the exemplary embodiment in an angular range of less than 10 °, in particular about 8 °. The angle α can advantageously also assume value ranges greater than 10 °, for example up to 30 °, or even significantly smaller values than 10 °. Basically, ranges of values in arbitrary gradations between approximately 1 ° and approximately 30 ° or possibly even beyond should be possible.

The angular arrangement of the carrier teeth 13 relative to the stator longitudinal axis 14 has the advantage that thereby a smoothing or homogenization of the

Torque curve can be achieved. Since a magnetic field is generated in each individual coil, each coil makes a contribution to the generation of torque, wherein due to the discrete number and positioning of the coils 17 seen over the circumference of the stator 4 is basically in a straight-aligned positioning of carrier teeth and Spools a rundown

Torque curve sets. By the proposed inclination of the carrier teeth of the non-round torque curve is smoothed.

Each carrier tooth 13 has an end section 16 into which the coil wire edges 17 a and 17 b are received in cuts 18. About the coil wire 17a and 17b, the electrical contact between the insulation displacement terminals 6 takes place on the contact ring 5 (FIG. 1).

The end portions 16 on each support tooth 13 are aligned coaxially or axially parallel to the stator longitudinal axis 14, so that each end portion 16 with the angularly oriented tooth base body 19 of each support tooth 13 also includes an angle α. This facilitates the axial placement or insertion of the insulation displacement terminals 6, which are held on the contact ring 5, on the coil wire ends 17a and 17b of each coil 17th

FIGS. 4a, 4b, 5 and 6 each show a carrier tooth 13, which forms a single stator element, in a single representation. 4a and 4b it can be seen that the coil 17 is wound around the base body 19 of the carrier tooth 13 and that the free coil wire ends 17a and 17b in the region of the end portion 16 which is integrally formed with the base body 19, through the cuts 18 in End portion 16 are guided.

From Fig. 5 it is seen that the tooth base body 19 is formed in cross-section double-T-shaped, so that lateral boundaries for the coil 17 are formed and the coil wire is securely held on the tooth base body 19. In the region of the double-T-shaped groove, the surface of the tooth base body 19, which is formed as a laminated core, is encapsulated with a plastic casing 20, whereby the coil 17 is electrically insulated from the base body 19. The remaining areas of the tooth base 19 have no plastic coating.

It may be expedient to provide the walls of the tooth base body in the region of the double T-slot with grooves for the wire of the coil 17, in which the wire is inserted and thereby guided safely.

As shown in FIG. 6, two parallel, mutually staggered receiving pockets 21 are introduced into the upper end face of the end portion 16, over which the coil wire ends 17 a and 17 b are guided. The cuts 18, in which the coil wire ends 17 a, 17 b are inserted, are introduced into the receiving pockets 21 defining walls. The receiving pockets 21 serve firstly to receive a chip (bauble), which during the process of Bonding process can occur with the insulation displacement terminals on the contact ring by shearing. On the other hand, the receiving pockets 21 serve to receive the axially projecting part of the insulation displacement terminals, whereby a compact design is achieved in the axial direction.

In Figures 7 and 8, the connection between immediately adjacent carrier teeth 13 is shown. The connection is preferably made exclusively by mechanical means using latching elements, which are designed in the embodiment as a clip connection 22. Each clip connection 22 comprises two latching elements, which are each arranged on a carrier tooth 13 and designed to be complementary to each other. In the exemplary embodiment, this is a Klipsvorsprung 23 on a first carrier tooth 13 and an associated, complementarily shaped Klipsausnehmung 24 on the immediately adjacent carrier tooth 13. The Klipsvorsprung 23 is executed ball or teilku- gelförmig or cylindrical, accordingly, the Klipsausnehmung

24 also provided with a spherical or part-spherical or cylindrical recess. In order to enable the required degree of elasticity for the realization of the clip connection, in which the clip elements are locked together, the elements of the clip connection consist of a material with sufficient elasticity and / or the clip elements have a relatively thin-walled construction or have a thin-walled section connected to the respective carrier tooth 13. It is thus possible, for example, to manufacture the clip elements of the clip connection 22 from a plastic material by molding the clip elements directly onto each carrier tooth. But it is also possible a version made of metal.

Figures 9 and 10 relate to the contact ring 5, which is carrier of the insulation displacement terminals 6, electrically connected to one another via the coils of different carrier teeth and supplied with current. The contact ring 5 consists of a plurality of individual rings 25, which are each carrier of the insulation displacement terminals 6 and which are axially stacked. Between each two axially adjacent individual rings 25 is a separating ring 27. Axial at the bottom is a base ring 26 as a carrier of all individual rings 25 and separating rings 27th By combining different individual rings 25, on each of which insulation displacement terminals 6 are arranged, a desired interconnection between the various coils of the stator can be achieved.

In Fig. 11, the electric motor 1 1 is shown in the assembled position, wherein the

Bearing plate 11, which is carrier of the electronic components 12 (Fig. 2), only indicated schematically. The contact ring 5 with the insulation displacement terminals 6 is placed on the front side of the stator for electrical connection with the coils on each support tooth of the stator. Axially protruding contact elements 28 for the electrical connection to the electronics or the power supply are arranged axially on the contact ring 5 on the side opposite the insulation displacement terminals 6.

As can be seen from FIG. 12, a magnetic element 29 is inserted into the axial end face of the rotor shaft 2 on the side facing the contact ring 5. This is preferably located in a recess in the end face of the rotor shaft. 2

The magnetic element 29 is part of a rotor position sensor via which the current rotor position of the rotor shaft 2 can be determined.

Claims

claims

1 . Stator in an electric motor (1), in particular in a setting or drive motor in motor vehicles, wherein the stator (4) has a plurality of circumferentially arranged Einzelstatorelemente, the carrier teeth (13), wherein each carrier tooth (13) wound with a Coil (17) is provided, wherein on the support teeth (13) locking elements (23, 24) for mechanical connection of the carrier teeth (13) are arranged one below the other.

2. Stator according to claim 1, characterized in that the latching elements

(23, 24) are designed as clips, such that a Klipsvorsprung (23) on a support tooth (13) in an associated Klipsausnehmung (24) on the adjacent support tooth (13) protrudes.

3. Stator according to claim 1 or 2, characterized in that the latching elements (23, 24) adjacent to the radial outer side of the carrier teeth (13) are arranged.

4. Stator according to one of claims 1 to 3, characterized in that the latching elements (23, 24) at least partially in the circumferential direction on the outside of the carrier teeth (13) protrude.

5. Stator according to one of claims 1 to 4, characterized in that the carrier teeth (13) have a plastic casing (20) and that the latching elements (23, 24) are formed integrally with the plastic of the respective carrier tooth (13).

6. Stator according to one of claims 1 to 5, characterized in that at least one latching element (23, 24) is formed elastically deformable.

7. Stator according to claim 6, characterized in that the elastically deformable latching element (23, 24) is connected via a reduced cross-section wall portion with the carrier tooth (13).

8. Stator according to one of claims 1 to 7, characterized in that the

Support teeth (13) exclusively mechanically by means of the latching elements (23, 24) are interconnected.

9. Stator according to one of claims 1 to 8, characterized in that the carrier teeth (13) have plastic-coated iron packets.

10. Stator according to one of claims 1 to 9, characterized in that the carrier teeth (13) with respect to the stator longitudinal axis (14) are arranged at an angle, so that the tooth longitudinal axis (15) of the carrier teeth (13) with the stator longitudinal axis (14 ) includes an angle (α).

1 1. Stator according to one of claims 1 to 9, characterized in that the electrical connection between the coils (17) by means of a contact ring (5), the carrier of electrical contact elements (6) via which the coil wire of a coil (18) the coil wire of another coil (17) is to be electrically connected.

12. Electric motor with a stator (4) according to one of claims 1 to 1 1.