Stator of an electrical machine

Abstract

A stator (1) for an electric machine (2) having a stator body (3) with a stator shaft (3.1) and electric stator coils (4), the stator body (3) having stator teeth (5) and stator slots (6) formed between the stator teeth (5), the stator body (3) including a stator disk (7), in particular a sheet metal and / or a cover disk for forming a laminated core, the stator coils (4) including a number of interconnected conductor elements (8), the pairs (9) of conductor ends (8e) of the conductor elements (8) being respectively fixed in the stator slots (6). A stator (1) in which the contact surfaces (12) of the pairs (9) of conductor ends (8e) are brought into contact with a contact force (13) at contact points (10) in the rotor slots (6) to form a contact joint (11), and the contact joint (11), in particular the contact force (13) for forming the contact joint (11), is generated by twisting at least one of the stator disks (7) of the stator body (3), in particular several stator disks (7), or one or more groups (14) of stator disks (7).

Description

Technical Field

[0001] The present invention starts from the stator of an electric machine based on the field of the main claim.

Background Art

[0002] The stator of an electric machine is already known from EP3138184B1. This stator has a stator body with a stator axis and an electrical stator coil. The stator body has stator teeth, and stator slots are formed between the stator teeth. The stator body includes stator disks for forming a laminated iron core. The stator coil has a number of conductor elements joined to each other. In the stator slots, pairs of conductor ends of a plurality of conductor elements are electrically contacted by contacting the contact surfaces of the pairs of conductor ends with a contact force at contact points within each stator slot. The contact force is generated by fixing the conductor ends of each conductor element with a wedge within the stator slot. Due to the accumulation of tolerances for each contact joint, it is difficult to reproducibly create a contact joint with good quality.

Summary of the Invention

[0003] In contrast, the stator according to the invention of an electric machine having the features of claim 1 has the advantage that the contact joint, in particular the contact force for forming the contact joint, is generated by the torsion of at least one, in particular several, stator disks of the stator body, or one or a plurality of groups of stator disks, so that the manufacturing of the stator coil is improved and / or simplified. In this way, the stator coil according to the invention can be manufactured without a material-bonded joint of the conductor elements, for example without welding. Moreover, this stator coil is composed of pre-formed conductor elements and can be plugged together, so that the conductor elements do not have to be entangled during the manufacturing of the stator coil.

[0004] Advantageous variations and improvements of the stator presented in claim 1 of an electric machine are possible by means of the measures listed in the dependent claims.

[0005] Particularly advantageous is the case where the twisted stator disk is within the axial region of each contact point and the tooth surface at least indirectly presses the contact surfaces circumferentially for mutual contact of the contact surfaces of each contact joint. In this way, the stator disk generates a clamping contact force for creating the contact joint.

[0006] It is even more advantageous if the conductor ends at at least one of the contact joints are interlocked in a shape-coupled manner. This allows for the formation of a sufficiently large contact surface for the contact joint.

[0007] A significant advantage is the case, based on the first exemplary embodiment, where one of the conductor ends of each contact joint has a recess, in particular a notch, and the other conductor end of the contact joint has a projection, in particular an angular tenon, that protrudes into the recess of the other conductor end, in which case the recess and projection of each contact joint have corresponding contact surfaces. In this way, a very simple and easily assembled plug-in joint is achieved as the contact joint. In this case, the angular projections of each conductor end of each conductor pair may have parallel or inclined contact surfaces.

[0008] It is also advantageous if the recess at one conductor end of each contact joint is longer in the axial direction relative to the stator axis than the projection at the other conductor end of each contact joint, thereby creating an adjustment gap. This allows tolerances to be filled, and these tolerances have an effect on each contact joint, such as the width of the stator slot, the width of the conductor cross-section of the conductor element, and the thickness of the insulating coating of the conductor element.

[0009] A further advantage is provided, based on the second exemplary embodiment, when both conductor ends of each contact joint have either a projection or a recess, and an additional joining element is provided as a third contacting partner of each contact joint, which joins both conductor ends of each contact joint to each other, in particular by surrounding both projections of both conductor ends or by being positioned within both recesses, and this additional joining element is formed in particular in the form of a sleeve, pin, or tenon. This allows for a larger contact surface to be achieved. Moreover, since plastic deformation can be generated in each of the three contacting partners when forming the contact joint, the clamping contact force that can be applied by the stator disk can be made smaller.

[0010] Furthermore, it is advantageous if a material bonding agent, particularly soft solder or a coating containing silver and / or nickel, is applied between the contacting mating parts of each contact joint, especially within the adjustment gap or on the surface of additional joining elements. This allows for material bonding in addition to shape bonding and force bonding between the conductor ends of each contact joint, thereby reducing contact resistance between conductor ends or improving electrical conductivity between conductor ends. Material bonding is formed by heating the stator to a temperature above the softening temperature of the bonding agent during manufacturing.

[0011] It is advantageous that the contact surfaces of each contact joint are formed parallel or nearly parallel to the tooth surfaces of the respective stator slots. This allows the contact joints to be implemented as push-fit joints. By axially inserting the pairs of conductor ends together, the contact surfaces of each contact joint are pressed toward each other by the twisted stator disk.

[0012] Each stator slot is provided with an additional element to generate additional contact force, which is particularly advantageous if this additional element is a spring element or a crimping element. This ensures that the overall contact force of each contact joint remains permanently at a sufficient height throughout the life of the stator.

[0013] It is even more advantageous if, in the area of ​​contact, a sleeve-shaped or cuff-shaped slot insulator is provided between each stator slot and the conductor element within the stator slot. This prevents the stator disk, twisted to form the contact joint, from damaging the insulation of the conductor element due to the contact force applied by the stator disk. This ensures that the stator body remains electrically insulated from the stator coil.

[0014] It is advantageous that the conductor elements of the stator coil are formed from flat wires and each has a rectangular conductor cross-section.

[0015] It is even more advantageous if the twisted stator disc, particularly thin sheet metal, is fixed within the stator body, especially by welding the twisted stator disc to adjacent stator discs, or by press-fitting the stator body to, for example, a stator housing that surrounds the stator. This ensures that the contact force can be maintained permanently.

[0016] In one advantageous embodiment, the stator coil is divided into at least two coil members axially with respect to the stator axis, each coil member comprising a number of conductive elements, the conductive ends of one coil member each in contact with one of the conductive ends of the other coil member, forming one contact joint, particularly by force coupling due to the torsion of a particular stator disk. That is, the torsion of the stator disk according to the present invention creates many contact joints simultaneously within the stator slot. In this way, the coil members of the stator coil can be axially interlocked and electrically connected, forming a number of contact joints according to the present invention due to the torsion of the stator disk relative to the stator coil according to the present invention. This can be done without material coupling of the conductive elements of the coil members, for example, without welding.

[0017] Furthermore, the present invention relates to an electromachine equipped with a stator according to the present invention.

[0018] Exemplary embodiments of the present invention are shown in the drawings, and will be described in more detail in the following description. [Brief explanation of the drawing]

[0019] [Figure 1] This figure shows a stator for an electromachine with a twisted stator disk according to the present invention for force-coupled electrical contact of pairs of conductor ends within the stator slots of the stator. [Figure 2] This is a cross-sectional view of a single stator slot of a stator based on Figure 1. [Figure 3] This figure shows detail X of Figure 2, based on the first exemplary embodiment. [Figure 4] This figure shows detail X of Figure 2, based on a second exemplary embodiment. [Figure 5] This figure shows detail X of Figure 2, based on a third exemplary embodiment. [Figure 6] This figure shows a pair of conductor ends according to the present invention for forming one of the contact joints according to the first embodiment of the first exemplary embodiment. [Figure 7]FIG. is a diagram showing a pair of conductor ends according to the present invention for forming one of the contact joints based on the second embodiment of the first exemplary embodiment. [Figure 8] FIG. is a diagram showing a pair of conductor ends according to the present invention for forming one of the contact joints based on the third embodiment of the first exemplary embodiment. [Figure 9] FIG. is a diagram showing a pair of conductor ends according to the present invention with additional elements for generating additional contact force.

BEST MODE FOR CARRYING OUT THE INVENTION

[0020] FIG. 1 shows a partial view of a stator of an electric machine provided with a twisted stator disk according to the present invention for force-coupled electrical contact of a pair of conductor ends in a stator slot of the stator.

[0021] The stator 1 according to the present invention of the electric machine 2 has a stator body 3 and an electrical stator coil 4. The stator body 3 has stator teeth 5, and stator slots 6 are formed between the stator teeth 5. The stator body 3 includes a stator disk 7 for forming a laminated iron core, particularly a thin sheet of electrical steel, and / or other disks, such as a cover disk.

[0022] The stator disks 7 shown in FIGS. 1 and 2 are drawn relatively thick for reasons of drawing, and each may also include a group of thin sheets, particularly of electrical steel.

[0023] The stator coil 4 includes a number of conductor elements 8 joined to each other.

[0024] Within the stator slot 6, pairs 9 of the conductor ends 8e of multiple conductor elements 8 are electrically in contact at each contact point 10 within the stator slot 6, by contact force, so as to form a contact joint 11. After the formation of the contact joint 11, each stator slot 6 may contain either only one electrical conductor or a conductor bundle containing multiple electrical conductors. The conductors of the conductor bundle overlap radially with respect to the stator axis 3.1, as shown in Figure 1.

[0025] The conductor elements 8 of the stator coil 4 are formed from, for example, flat wire and each has a rectangular conductor cross-section. The conductor elements 8 of the stator coil 4 may further have, for example, an insulating coating 8i.

[0026] To clearly illustrate the present invention, Figure 1 shows the stator coil 4 in only one of the stator slots 6. The stator coil 4 forms coil ends 4.1 at both end faces of the stator body 3.

[0027] Figure 2 shows a cross-sectional view of a single stator slot 6 of stator 1 based on Figure 1.

[0028] Figure 3 shows a diagram of detail X in Figure 2, based on the first exemplary embodiment.

[0029] According to the present invention, the contact joint 11, and in particular the contact force for forming the contact joint 11, is generated by the torsion of at least one of the stator disks 7 of the stator body 3, in particular several stator disks 7, or one or more groups of stator disks 7. The contact joint 11 can be generated by the torsion in opposite directions of the stator disks 7 or groups 14 of stator disks 7, as shown in Figures 3 to 5. The torsion of the stator disks 7 is performed at a torsion angle φ around the stator axis 3.1.

[0030] The twisted stator disc 7 is fixed within the stator body 3, in particular by welding the twisted stator disc 7 to adjacent stator discs 7, or by press-fitting the stator body 3 to the stator housing surrounding the stator body 3.

[0031] The stator coil 4 may be divided into at least two coil members in an axial direction with respect to the stator shaft 3.1 in a manner not shown, and each coil member may consist of a number of conductor elements 8. According to the present invention, each conductor end 8e of one coil member may be in contact with one of the conductor ends 8e of the other coil member, forming one of the contact joints 11 in a force-coupled manner, particularly by the twisting of a particular stator disk 7.

[0032] The twisted stator disk 7 is located within the axial region of each contact point 10 relative to the stator shaft 3.1, and the tooth surfaces 7.1 press the contact surfaces 12 against the stator shaft 3.1 at least indirectly due to the mutual contact of the contact surfaces 12 of each contact joint 11.

[0033] The contact points 10 and contact joints 11 of pairs of conductor ends 8e located within the same stator slot 6 can be in the same or different axial positions within each stator slot 6.

[0034] The conductor ends 8e at at least one of the contact joints 11 are paired and interlocked in a shape-coupled manner.

[0035] The contact surfaces 12 of each contact joint 11 are formed parallel or nearly parallel to the tooth surfaces 5.1 of each stator slot 6. By inserting pairs of conductor ends 8e axially, the contact surfaces 12 of each contact joint 11 are pressed toward each other by the twisted stator disk 7.

[0036] Based on the first exemplary embodiment, one of the conductor ends 8e of each contact joint 11 has a recess 16, in particular a notch, and the other conductor end 8e of the contact joint 11 has a projection 17, in particular an angular tenon, that protrudes into the recess 16 of the other conductor end 8e. The recess 16 and projection 17 of each contact joint 11 have corresponding contact surfaces 12. Each contact joint 11 is formed such that the recess 16 of one conductor end 8e of each contact joint 11 is longer in the axial direction with respect to the stator shaft 3.1 than the projection 17 of the other conductor end 8e of the contact joint 11.

[0037] In the area of ​​the contact point 10, a sleeve-shaped or cuff-shaped slot insulating portion 21 may be provided between each stator slot 6 and the conductor element 8 located within each stator slot 6.

[0038] Figure 4 shows a detail X of Figure 2, based on a second exemplary embodiment.

[0039] Based on the second exemplary embodiment, both conductor ends 8e of each contact joint 11 each have a projection 17. In addition, an additional joining element 19 is provided as a third contact partner of each contact joint 11, which joins both conductor ends 8e of each contact joint 11 to each other, in particular by sleeve-like surrounding both projections 17.

[0040] Figure 5 shows a diagram of detail X in Figure 2, based on a third exemplary embodiment.

[0041] Based on the third exemplary embodiment, both conductor ends 8e of each contact joint 11 each have a recess 16. In addition, an additional joining element 19 is provided as a third contact partner of each contact joint 11, which joins both conductor ends 8e of each contact joint 11 to each other, in particular by positioning the joining element 19 within both recesses 16 of both conductor ends 8e, or by protruding into both recesses 16. Based on the third exemplary embodiment, the additional joining element 19 is formed in the shape of a pin or tenon.

[0042] In addition to the shape-bonding and force-bonding according to the present invention, material-bonding joints can be made by applying a material-bonding adhesive, particularly a soft solder or a coating containing silver and / or nickel, between the contact partners 8e and 19 of each contact joint 11, in particular within the adjustment gap 18 or on the surface of the additional joint element 19.

[0043] Figure 6 shows a pair of conductor ends according to the present invention for forming one of the contact joints according to the first embodiment of the first exemplary embodiment.

[0044] According to the first embodiment, the projection 17 of one conductor end 8e, which is implemented as an angular stepped tenon, is inserted into the recess 16 of the other conductor end 8e, thereby being completely surrounded by the other conductor end 8e and thus becoming invisible.

[0045] Figure 7 shows a pair of conductor ends according to the present invention for forming one of the contact joints according to a second embodiment of the first exemplary embodiment.

[0046] According to the second embodiment, the recess 16 of one conductor end 8e is implemented as a notch formed from end to end in the height or width direction of the conductor end 8e. For example, the recess 16 forms a fork-shaped conductor end 8e. A projection 17 of the other conductor end 8e, implemented as an angular tenon, is inserted between the teeth 15 of the fork-shaped conductor end 8e to form a dovetail or scherzapfen (terminology relies on wood joint or timber joint) contact joint 11. The notch 16 and tenon 17 can be formed in a corresponding wedge shape so that the contact joint 11, based on the generation of contact forces by the twisting of the stator disk 7, can withstand axial pull-out forces against undesirable separation of the contact joint 11.

[0047] Instead of dovetail or three-piece joints, the conductor ends of each pair of conductor ends may form a so-called gerades Blatt, and the terminology is based on wood joints or timber joints.

[0048] Figure 8 shows a pair of conductor ends according to the present invention for forming one of the contact joints according to a third embodiment of the first exemplary embodiment.

[0049] According to the second embodiment, the contact joint is implemented in the form of a saddle joint (zapfenblattstoss).

[0050] Figure 9 shows a pair of conductor ends according to the present invention with additional elements for generating additional contact force.

[0051] Within the stator slot 6, additional elements 20 may be provided in each region of the contact points 10 to generate an additional contact force that presses the contact surfaces 12 together. These additional elements 20 are particularly spring elements or crimping elements, and are implemented, for example, in the form of sleeves or clamps. The additional elements 20 may, for example, bite into the material of the conductor end 8e at their tip portions 20.1.

Claims

1. A stator (1) of an electric machine (2) having a stator body (3) having a stator shaft (3.1) and an electric stator coil (4), wherein the stator body (3) has stator teeth (5), and stator slots (6) are formed between the stator teeth (5), the stator body (3) includes a stator disk (7), the electric stator coil (4) includes a number of interconnected conductor elements (8), and within the stator slots (6), pairs (9) of the conductor ends (8e) of the multiple conductor elements (8) are electrically in contact at each contact point (10) within the stator slot (6) by contact force (13) between the contact surfaces (12) of the pairs (9) of the conductor ends (8e), thereby forming a contact joint (11). A stator (1) characterized in that the contact force (13) for forming the contact joint (11) is generated by the twisting of at least one of the stator disks (7) of the stator body (3), or one or more groups (14) of the stator disks (7) of the stator body (3).

2. The stator according to claim 1, characterized in that the twisted stator disk (7) is located within the axial region of each of the contact points (10), and the tooth surface (7.1) presses the contact surface (12) at least indirectly in the circumferential direction for mutual contact of the contact surfaces (12) of each of the contact joints (11).

3. The stator according to claim 1, characterized in that the conductor end (8e) at at least one of the contact joints (11) is inserted into a shape-coupled manner.

4. Each of the contact joints (11) has a recess (16) at one of its conductor ends (8e), and the other conductor end (8e) of the contact joint (11) has a projection (17) that protrudes into the recess (16) of the other conductor end (8e), The stator according to claim 1, characterized in that each of the contact joints (11) has a corresponding contact surface (12) where the recess (16) and the protrusion (17) are located.

5. The stator according to claim 4, characterized in that the recess (16) of one conductor end (8e) of each contact joint (11) is formed to be longer in the axial direction with respect to the stator shaft (3.1) than the protrusion (17) of the other conductor end (8e) of each contact joint (11), thereby forming an adjustment gap (18) in each case.

6. The stator according to claim 1, wherein both conductor ends (8e) of each contact joint (11) each have a projection (17) or a recess (16), and an additional joining element (19) is provided as a third contact partner of each contact joint (11), and the additional joining element (19) joins both conductor ends (8e) of each contact joint (11) to each other by surrounding both projections (17) of both conductor ends (8e) or by being positioned within both recesses (16), and the additional joining element (19) is formed in the shape of a sleeve, pin, or tenon.

7. The stator according to claim 6, characterized in that a material bonding agent is applied between the additional bonding elements (19) of each of the contact bondings (11).

8. The stator according to claim 1, characterized in that the contact surface (12) of each of the contact joints (11) is formed parallel to or substantially parallel to the tooth surface (5.1) of each of the stator slots (6).

9. The stator according to claim 1, wherein an additional element (20) for generating an additional contact force is provided in each of the stator slots (6), and the additional element (20) is a spring element or a crimping element.

10. The stator according to claim 1, characterized in that, in the region of the contact area (10), a sleeve-shaped or cuff-shaped slot insulating portion (21) is provided between each of the stator slots (6) and the conductor element (8) located within the stator slot (6).

11. The stator according to claim 1, characterized in that the conductor elements (8) of the electrical stator coil (4) are formed from flat wires and each has a rectangular conductor cross-section.

12. The stator according to claim 1, characterized in that the twisted stator disc (7) is fixed within the stator body (3) by welding the twisted stator disc (7) to an adjacent stator disc (7), or by press-fitting the stator body (3) to the stator housing.

13. The stator according to claim 1, characterized in that the electrical stator coil (4) is divided into at least two coil members in the axial direction with respect to the stator shaft (3.1), each coil member is composed of a number of conductive elements (8), and the conductive end (8e) of one coil member is in contact with one of the conductive ends (8e) of the other coil member, forming one of the contact joints (11) in a force-coupled manner by the twisting of a specific stator disk (7).

14. The stator according to claim 1, wherein the stator disk (7) is a thin sheet metal or cover disk for forming a laminated iron core.

15. An electric machine (2) comprising a stator (1) according to any one of claims 1 to 14.

Images