WO2020144067A1

WO2020144067A1 - Electric motor

Info

Publication number: WO2020144067A1
Application number: PCT/EP2019/086951
Authority: WO
Inventors: Andrzej Antonowicz; Ortwin Elsaesser; Gyoergy Mucsi; Peter Nadig
Original assignee: Robert Bosch Gmbh
Priority date: 2019-01-09
Filing date: 2019-12-23
Publication date: 2020-07-16
Also published as: DE102019200155A1

Abstract

The invention relates to an electric motor, in particular a brushless permanent magnet synchronous motor, comprising a rotor, a stator, said stator having a laminated core and at least one winding consisting of a wire, and a connection plate. According to the invention, the connection plate has at least one guide path, in which the wire of at least one winding is guided.

Description

Electric motor

State of the art

DE 10 2014 212 566 A1 describes an electronically commutable electric motor with a connecting plate.

Disclosure of the invention

The invention relates to an electric motor, in particular a brushless permanent magnet synchronous motor, with a rotor, with a stator, the stator having a laminated core and at least one winding consisting of a wire, and with a connection plate. It is proposed that the connection plate has at least one guideway in which the wire of the at least one winding is guided. A contact-free guidance of the wires can advantageously be implemented in a structurally simple manner by such a connection plate.

The electric motor can, for example, as a drive motor for a hand tool machine, for an electromechanical tool, for an actuator of a windshield wiper, window, seat, pump, for a suction device, for a vacuum cleaner, for a vehicle, a bicycle, a household appliance, one Fan, a toy etc. are used. The handheld power tool can be designed as a network handheld power tool or as a cordless handheld power tool. The hand-held power tool can in particular be designed as a screwdriver, a drill, a rotary hammer, a hammer, a saw, a milling machine, a grinding machine, an angle grinder, a multifunction device, a gardening implement, etc.

A brushless permanent magnet synchronous motor is to be understood in particular as an electric motor with a three-phase winding which can be controlled or regulated via a control unit such that a rotating magnetic field is generated which pulls a permanently excited rotor. The permanent magnet Syn chronmotor is designed in particular as a DC motor.

The rotor is, in particular, rotatable about an axis of rotation of the electric motor. The rotor has at least two magnetic elements. The magnetic elements NEN can be attached to the outer surface of the rotor or arranged in receiving pockets of the rotor.

The stator has a laminated core which is connected to the winding. The electric motor is preferably designed as an inner rotor, the rotor being arranged on the inside with respect to the stator. Alternatively, it is also conceivable that the electric motor is designed as an external rotor, the rotor being arranged on the outside in relation to the stator.

The winding is in particular ausgebil det as a stator winding or phase winding. The electric motor preferably has at least three windings, each consisting of a wire. The wire can be formed, for example, as a copper wire with enamel insulation. The wire can be formed in one piece or in one piece. In the context of this application, a one-piece component is to be understood in particular as a single component which is preferably made from one piece. A one-part component should in particular also be understood to mean two or more components which are connected to one another via a material connection. The electric motor preferably has at least three windings which can be controlled at least partially independently of one another.

The connection plate is arranged on an end plate opposite side of the laminated core of the stator. The connection plate and / or the end plate are made of an electrically insulating material, in particular of a plastic, ausgebil det. The connection plate and / or the end plate are in particular non-positively and / or positively connected to the laminated core. The connection plate and / or the end plate preferably have at least one arm, preferably at least one arm per winding, around which the winding is partially wound outside the laminated core. The connection plate is preferably formed in one piece or in one piece.

In particular, the guideway is designed such that the wire is circumferentially direction of the electric motor is guided. The guide path of the connection plate can be formed continuously or interrupted along the circumferential direction of the electric motor. The guideway in particular has an essentially L-shaped and / or an essentially U-shaped cross section. In a section with an L-shaped cross section, the guideway has, in particular, a wall which secures the wire arranged in the guideway axially in a single direction. In a section with an L-shaped cross section, the wire is guided on one side, with the wire being guided on both sides in a section with a U-shaped cross section. In a section with a U-shaped cross section, the guide track has in particular two opposite walls, which axially secures the wire arranged in the guide track in two opposite directions. The guide track in the circumferential direction preferably has an L-shaped or a U-shaped cross section at one beginning and also an L-shaped or a U-shaped cross section at one end. Between the beginning and the end of the guideway, the guideway extends in an angular range of at least 25 °, in particular at least 50 °, preferably at least 90 °, preferably at least 150 °, about the axis of rotation of the electric motor. The guideway can be arranged on a radially outer side of the connection plate or on a radially inner side of the connection plate. The guideway is in particular formed in one piece with the connecting plate.

Furthermore, it is proposed that the connection plate has at least one guideway per winding, in which the wire of the at least one winding is guided. This measure can advantageously ensure that the wires are sufficiently insulated from one another.

Furthermore, it is proposed that the connection plate has at least two guideways which are designed such that two wires are guided parallel to one another in the circumferential direction of the electric motor. The connection plate preferably has at least three guideways which are designed such that three wires are guided parallel to one another in the circumferential direction of the electric motor. Alternatively or additionally, it is also conceivable that the connection plate has at least two guide tracks, in which the same wire is spaced apart and guided parallel to itself. It is also proposed that the guideways have a different radial distance. As a result, the distance between the wires arranged in the guide tracks can advantageously be increased from one another. In this context, a radial distance was to be understood in particular as a distance between the guideway or the wire arranged in the guideway and the axis of rotation of the electric motor. In particular, the difference between the radial distances between the guideways is at least half the diameter of the wire, preferably at least two thirds of the diameter of the wire, preferably at least the diameter of the wire.

Furthermore, it is proposed that the connection plate have at least one recess through which the wire is guided essentially radially to an axis of rotation of the rotor. The cutouts can advantageously be used for cross-laying of the wires. In particular, the wire is guided in the recess essentially radially outwards or essentially radially inwards. Before preferably the recess is designed to receive or guide a single wire. The recess preferably has an end opening through which the wire can be received at the end, in particular when winding the wire. The end-side opening is arranged on a side of the connection plate opposite the laminated core of the rotor.

It is further proposed that the connection plate has at least one first recess and at least one second recess, each of which is assigned to a winding, a depth of the first recess being different from a depth of the second recess. In particular, the at least one first recess is associated with a first guideway and the at least one second recess is associated with a second guideway. The connecting plate preferably has at least two cutouts per guide track, preferably at least four cutouts. In the context of this application, a depth of the recess is to be understood in particular as a length of the recess parallel to the axis of rotation of the electric motor between the front opening of the recess and a bottom of the recess.

It is also proposed that the connection plate have at least three connection areas, in each of which a single wire with an electrical contact element is connected. The connection of the electrical contact elements with the wires can take place via a material connection, such as a welding process, in particular a resistance pressure welding process, a soldering process or a crimping process. In particular, the connection plate has receptacles for the electrical contact elements, which are designed for the non-positive and / or positive connection of the connection plate to the electrical contact elements.

Furthermore, it is proposed that the electric motor have at least three connection areas, in each of which at least one recess is arranged and via which a wire is connected to a coil area of the winding.

The connection areas are arranged one behind the other in the circumferential direction, the depth of the cutouts increasing or decreasing in the circumferential direction.

Furthermore, the invention relates to a connection plate for an electric motor as described above.

In addition, the invention relates to a method for producing an electric motor designed as an electronically commutatable permanent magnet synchronous motor, comprising the following steps:

- Assembly of an end plate and a connection plate on a laminated core;

- Isolation of the laminated core by means of an insulating agent;

- winding the wires;

- Guide the wires in guideways of the connection plate, which extend in the circumferential direction of the electric motor, to electrical contact elements;

- physical connection of the wires to the electrical contact elements. In this context, a physical connection should in particular be understood to mean that the wires lie directly on the electrical contact elements. Before preferably the wires are electrically connected to the electrical contact elements via a non-positive and / or positive connection or via a material connection. The insulating means can be designed, for example, as an insulating paper or an insulating plastic. drawings

Further advantages result from the following description of the drawing. The drawings, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into useful further combinations.

Show it:

Figure 1 is a side view of an electric motor according to the invention.

2 is a front view of the electric motor;

Fig. 3a is a perspective view of a connection plate of the electromotive gate according to FIG. 1;

3b shows a side view of the connection plate according to FIG. 3a;

Fig. 4 shows a section through the connection plate.

Description of the embodiments

In Fig. 1 is a side view of an electric motor 10 according to the invention shows ge. 2, the electric motor 10 is shown in a front view. The electric motor 10 is designed as an electronically commutated DC motor 12, for example. The electric motor 10 has a rotor 14 which is enclosed by a stator 16. The electric motor 10 is thus designed, for example, as an inner rotor. The rotor 14 is designed to be permanently excited. By way of example, a plurality of permanent magnet elements (not shown) are attached to the rotor 14. The rotor 14 has an armature shaft 18 which is designed to be rotatable about an axis of rotation 20 of the electric motor 10.

The stator 16 comprises a laminated core 22 and three windings 24, each consisting of a wire 26. The individual windings 24 consist in particular from a single wire 26. The windings 24 have a coil region 28, in which the winding 24 is wound around a pole core (not shown) of the sheet metal package 22 to form a coil 30. In particular, each winding 24 has two coil regions 28. The electric motor 10 has, for example, three windings 24, each with two coil regions 28, which are arranged opposite one another with respect to the rotational axis 20. Furthermore, the windings 24 have a wire region 32, in which the wire 26 of the winding 24 is not wound or runs at a distance from it.

The laminated core 22 is connected to an end plate 34 and a connecting plate 36. The end plate 34 and the connection plate 36 are formed from an electrically insulating material, for example plastic. The end plate 34 and the connecting plate 36 have arms 38 (see FIG. 2) which, for example, extend radially inwards. The arms 38 are integrally formed with the Anschlussplat te 36 or with the end plate 34. The arms 38 have a cross section which essentially corresponds to a cross section of the pole core and a pole shoe of the laminated core 22. In a coil region 28, the winding 24 is wound both around the pole core of the laminated core 22 and around the arms 38 of the end plate 34 and the connecting plate 36.

The electric motor 10 also has a fan element 40 which is connected to the armature shaft 18 in a rotationally fixed manner. The fan element 40 is arranged on a side of the stator 16 facing away from the connection plate 36. On one of the connection plate 36 facing side of the stator 16, an electronics module 42 is arranged (see FIG. 2). The electronics module 42 comprises a printed circuit board 44 on which a sensor unit 46 is arranged. The sensor unit 46 is in particular designed to detect a motor parameter of the electric motor 10. The electronics module 42, in particular the sensor unit 46, is connected to a control unit, not shown, which is designed to control or regulate the electric motor 10. The control unit is provided with the motor parameter, wherein a rotor position, a speed and / or a load of the electric motor 10 can be determined by the control unit based on the motor parameter. The sensor unit 46 includes, for example, at least one Hall sensor element. The circuit board 44 of the electronics module 42 is accommodated in an electronics module housing 48. The electronics module 42 is firmly connected to the electric motor 10, in particular to the stator 16, via the connection plate 36. The connection of the electronics module 42, in particular the electronics module housing 48, with the connection plate 36 is carried out, for example, via a screw connection.

The wires 26 of the windings 24 are connected to each other in a star connection. Alternatively, it would also be conceivable that the wires are interconnected in a delta connection. A first wire 50 of a first winding 52 is electrically connected to a first electrical contact element 56 and a fourth electrical contact element 58. A second wire 60 of a two-th winding 62 is electrically connected to a second electrical contact element 64 and to the fourth electrical contact element 58. A third wire 66 of a third winding 68 is electrically connected to a third electrical contact element 70 and the fourth electrical contact element 58.

The first electrical contact element 56 and the second electrical contact element 64 are received by the connection plate 36. The third electrical contact element 70 and the fourth electrical contact element 58 are accommodated in the electronics module housing 48. Alternatively, however, it would also be conceivable that all electrical contact elements 56, 58, 64, 70 are received by the connection plate 36 or by the electronics module housing 48.

3a and 3b, the connection plate is shown in a perspective view and a side view without the wires 26. The connection plate 36 is in particular designed to guide the wires 26 of the windings 24 between the coil regions 28 and / or between the electrical contact elements 56, 58, 64, 70 at a distance from one another.

The connection plate 36 has a substantially cylindrical base body 72, from the inner surface 74 of which the arms 38 of the connection plate 36 extend ra dial inwards. The inner surface 74 encloses an interior space 76 of the connection plate 36, in which the coil regions 28 of the windings 24 are arranged. To guide the wires 26, the connection plate 36 has guide tracks 78 which are attached to an outer surface 80 of the connection plate 36. are arranged. The outer surface 80 is arranged on a side surface facing away from the inner surface 74, in particular opposite it. The guideways 78 extend substantially in the circumferential direction 82 of the electric motor 10.

The outer guideways 78 are connected to the interior 76 via Ver connection areas 84. In particular, each coil region 28 has a connection region 84, via which the wires 26 can be guided away from the coil region 28 and / or towards the coil region. As an example, the electric motor 10 has six connection areas 84, in each of which a wire 26 is guided radially inwards to the coil area 28 and radially outwards from the coil area 28. The connection areas 84 each comprise two cutouts 86. A single wire 26 is arranged or guided in each of the cutouts 86. Within a connection area 84, the same wire 26 is guided through a cutout 86 from the outer surface 80 of the connection plate 36 to the coil area 28 and through a further cutout 86 from the coil area 28 to the outer surface 80.

In order to prevent the wires 26 arranged in the guide tracks 78 from crossing, the connecting plate 36 has at least one guide track 78 per wire 26, the guide tracks 78 being spaced apart from one another.

On the one hand, the guideways 78 are axially spaced from one another, in that the guideways 78 extend in the circumferential direction 82 parallel to one another but at a distance which, for example, is greater than the thickness of the wires 26 (see FIG. 1). The cutouts 86 are designed such that the wires 26 are guided essentially directly into the respective guide tracks 78. In particular, the connection plate 36 has differently designed recesses 86 for each guide track 78, which differ from one another in their depth.

1 shows, by way of example, two first cutouts 88, which have a first depth 90, two second cutouts 92, which have a second depth 94, and a third cutout 96, which has a third depth 98. The first recess 88 is assigned to a guideway 78 in which the first Wire 50 is guided. The second recess 92 is associated with a guideway 78 in which the second wire 60 is guided. The third recess 96 is assigned to a guideway 78 in which the third wire 66 is guided. The first tie fe 90 is greater than the second depth 94 and the second depth 94 is greater than the third depth 98. The depth results from a distance between an end opening 100 of the recess 86, via which the wire 26 can be received in the recess 86, and a recess reason 102. Within a connecting area 84, the depth of the recesses 86 is essentially constant.

The wires 26 are in the guideways 78 between two Spulenberei Chen 28 a winding 24 or between the two electrical Kontaktelemen th, with which the respective wire 26 is electrically connected. The leadership can take place on one or both sides and in sections or continuously. In the exemplary embodiment shown, the guide is formed on one side and from sections. The one-sided guidance takes place via walls 104, which prevent lateral displacement in the axial direction. The walls 104 are formed, for example, in one piece with the connection plate 36. The guide rail 78, in which the first wire 50 is arranged, are associated with first walls 106.

In the illustration shown in FIG. 1, the first wire 50 is guided, for example, by five first walls 106, the walls 104 being formed at a distance from one another in the circumferential direction 82. The first walls 106 are arranged in such a way that they limit an axial displacement of the wire 26 in a direction facing and facing away from the laminated core 22.

In the illustration shown in FIG. 1, the second wire 60 is guided by four second walls 108, the second walls 108 being spaced apart from one another in the circumferential direction 82. The second walls 108 are arranged in such a way that they limit an axial displacement of the wire 26 in a direction facing and facing away from the laminated core 22. The third wire 66 is in turn guided analogously by third walls 110. FIG. 4 shows a section A through the area marked in FIG. 1. The walls 104 have a height 112 which essentially corresponds to the thickness of the wires 26. The first, second and third walls 106, 108, 110 have a substantially same height 112. The second wall 108 is arranged on the first wall 106, so that the guideway 78 on which the second wire 60 runs is radially spaced from the guideway 78 of the first wire 50 by the height 112 of the wall 104. The third wall 110 is arranged on the second wall 108 so that the guideway 78, on which the third wire 66 runs, radially from the guideway 78 of the second wire

60 is spaced by the height 112 of the wall 104. The guide tracks 78 are at a greater axial distance than a radial distance. From the axial position, for example, essentially corresponds to twice the thickness of the wires 26.

Claims

Expectations

1. Electric motor, in particular brushless permanent magnet synchronous motor (12), with a rotor (14), with a stator (16), the stator (16) being a laminated core (22) and at least one winding (24) consisting of a wire (26) ), and with a connection plate (36), characterized in that the connection plate (36) has at least one guide track (78) in which the wire (26) of the at least one winding (24) is guided.

2. Electric motor according to one of the preceding claims, characterized in that the connection plate (36) per winding (24) has at least one guide track (78) in which the wire (26) of the at least one winding (24) is guided.

3. Electric motor according to one of the preceding claims, characterized in that the at least one guide track (78) is designed such that the wire (26) is guided in the circumferential direction (82) of the electric motor (10).

4. Electric motor according to one of the preceding claims, characterized in that the connection plate (36) has at least two guideways (78) which are designed such that two wires (26) parallel to each other in the circumferential direction (82) of the electric motor (10 ) are performed.

5. Electric motor according to one of the preceding claims, characterized in that the guide tracks (78) have a different radial distance.

6. Electric motor according to one of the preceding claims, characterized in that the connecting plate (36) has at least one recess (86) through which the wire (26) is guided radially to an axis of rotation (20) of the rotor (14).

7. Electric motor according to one of the preceding claims, characterized in that the connection plate (36) has at least one first recess (88) and at least one second recess (92), each of which is in particular assigned to a winding (26), wherein a depth (90) of the first recess (88) differs from a depth (94) of the second recess (92).

8. Electric motor according to one of the preceding claims, characterized in that the electric motor (10) has at least three connecting areas (84), in each of which at least one recess (86) is arranged and over each of which a wire (26) is connected to a coil region (28) of the winding (26).

9. Connection plate for an electric motor (10) according to one of the preceding claims, wherein the connection plate (36) has at least two guideways (78) which are designed to guide two wires (26) of two different windings (24).

10. A method for producing an electronically commutatable permanent magnet synchronous motor (12) in the form of an electric motor (10), comprising the following steps:

- Installation of an end plate (34) and a connecting plate (36) on a laminated core

(22);

- winding of wires (26) for producing at least one coil region (28);

- Guide the wires (26) in guideways (78) of the connection plate (36), which extend in the circumferential direction (82) of the electric motor (10), to electrical contact elements (56, 58, 64, 70);

- Physical connection of the wires (26) with the electrical contact elements (56,

58, 64, 70).