Stator, electric motor and working machine

Abstract

This stator includes: a stator core having a cylindrical shape and including a plurality of slots arranged in a circumferential direction; a stator coil inserted into each of the plurality of slots, wound around the stator core, and including a plurality of terminal-side extension sections extending axially outward from a first end surface of the stator core and arranged in the circumferential direction; and a fastening section configured to fasten circumferentially adjacent sections in the plurality of terminal-side extension sections.

Description

TECHNICAL AREA

[0001] The present disclosure relates to a stator, an electric motor and a working machine.

[0002] The present application claims priority over Japanese patent application No. 2023-201045, filed on November 28, 2023, the contents of which are incorporated herein by reference. STATE OF THE ART

[0003] Patent document 1 discloses a configuration, including: a stator core with slots for inserting a winding; Phase windings that are to be led out to an axial end section of the stator core; a neutral conductor separate from the phase winding and a fastening device for securing each of the phase windings to which the neutral conductor is connected and the adjacent phase winding. LIST OF COUNTERPOINTS Patent Literature

[0004] Patent Document 1: JP 2016-15797 A BRIEF DESCRIPTION OF THE INVENTION Technical Problem

[0005] However, in the configuration of patent document 1, the fastening sections of each adjacent phase winding are located at low positions in the radial direction, so there is a high probability that it will be difficult to position the fasteners. If the fasteners cannot be positioned properly, the fastening strength of each phase winding may be reduced.

[0006] One of the purposes of the present disclosure is to provide a stator, an electric motor and a working machine which can improve the ease of assembly and the strength of fastening. SOLUTION TO THE PROBLEM

[0007] A stator, according to one aspect of the present disclosure, includes: a stator core with a cylindrical shape, having a plurality of circumferentially arranged slots; a stator coil inserted into each of the plurality of slots, wound around the stator core and including a plurality of terminal-side extension sections extending axially outward from a first end surface of the stator core and arranged circumferentially; and a fastening section configured to fasten circumferentially adjacent sections in the plurality of terminal-side extension sections. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0008] One aspect of the present disclosure makes it possible to provide a stator, an electric motor and a working machine which can improve the ease of assembly and the strength of fastening. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a schematic diagram illustrating a working machine according to one embodiment. Fig. Figure 2 is a cross-sectional view of an electric motor according to one embodiment. Fig. Figure 3 is a perspective view of a stator according to one embodiment. Fig. Figure 4 is a perspective view of an inner circumferential section of a stator according to one embodiment. Fig. Figure 5 is a perspective view of a section in which a fastening section is attached in a plurality of connection-side extension sections according to an embodiment. Fig. Figure 6 is a view of a slot of a stator according to an embodiment, taken in a plane orthogonal to the axial direction. Fig. Figure 7 is a view illustrating a segmented coil before mounting it on a stator core according to one embodiment. Fig. Figure 8 is a view illustrating a segment coil according to one embodiment after twisting. Fig. Figure 9 is a connection diagram of a stator coil according to one embodiment. Fig. Figure 10 is a perspective view illustrating a modification example of a section in which a fastening section is attached in a plurality of connection-side extension sections according to one embodiment. Fig. Figure 11 is another perspective view illustrating a modification example of a section in which a fastening section is attached in a plurality of connection-side extension sections according to one embodiment. DESCRIPTION OF EXECUTION FORMS

[0009] An embodiment of the present disclosure is described in detail below with reference to the drawings. In the present embodiment, an example is described in which an electric motor is mounted on an electric rotary excavator (an example of a working machine) and is configured as a rotary motor for rotating an upper rotating body of the electric rotary excavator.

[0010] In the following description, terms indicating relative or absolute positional relationships, such as "parallel," "orthogonal," "centered," and "coaxial," are not strictly limited to such arrangements or conditions, but also include arrangements or conditions that are relatively displaced within tolerances or to the extent that the same function can be achieved. In the drawings used in the following description, the scales of the respective elements may have been appropriately modified to allow for their identification. work machine

[0011] Fig. Figure 1 is a schematic diagram illustrating a working machine according to one embodiment. A working machine 100 according to the present embodiment is an electric hydraulic excavator. The working machine 100 can be a manned vehicle operated by a driver or an unmanned vehicle operated without a driver.

[0012] The working machine 100 includes a drive body 120, an upper rotating body 140 and a working device 160.

[0013] The chassis 120 carries the working machine 100 so that it can move. The chassis 120 encloses a drive mechanism 121. The chassis 121 consists, for example, of a pair of left and right crawler tracks. The drive mechanism 121 is driven by a drive motor 122. The upper rotating body 140 is rotatably supported by the chassis 120 about a pivot axis. The upper rotating body 140 performs a rotational operation relative to the chassis 120 by means of the rotary motor 114. The upper rotating body 140 encloses a compartment 141 for housing a drive system.

[0014] The working device 160 is supported during operation by the upper rotating body 140. The working device 160 is driven by hydraulic pressure. The working device 160 includes a boom 161, an arm 162, and an attachment 163. The attachment 163 is an example of a working tool. The attachment 163 in the Fig. The first illustrated example is a shovel. In the one shown in Fig. In the illustrated example 1, the side of the upper rotating body 140 with the mounted working tool 160 is the front, and the opposite side with respect to the front is the back. In the present embodiment, the left-right direction refers to left and right with respect to the front, and the up-down direction refers to the direction in which the axis of rotation of the upper rotating body 140 extends.

[0015] The rotary motor 114 is an electric motor driven by electrical power. The rotary motor 114 rotates the upper rotating body 140 relative to the transport body 120. electric motor

[0016] Fig. Figure 2 is a cross-sectional view of an electric motor 1 according to one embodiment.

[0017] In the present embodiment, the electric motor 1 is a rotary motor 114. The electric motor 1 includes a rotor 2, a stator 3, and a housing 4 for receiving the rotor 2 and the stator 3. The electric motor 1 is of the type of internal rotor motor, in which the stator 3 is arranged outside the cylindrical rotor 2. The electric motor 1 is positioned vertically such that a rotor shaft 20 of the rotor 2 is parallel to the axis of rotation.

[0018] In the present embodiment, the upper side corresponds to a side parallel to a central axis CL of the rotor shaft 20, and the lower side corresponds to the other side parallel to the central axis CL of the rotor shaft 20. Hereinafter, a direction along the central axis CL of the rotor shaft 20 is referred to as the "axial direction", a direction orthogonal to the axial direction is referred to as the "radial direction", and a direction circumferential around the central axis CL of the rotor shaft 20 is referred to as the "circumferential direction".

[0019] The rotor 2 includes the rotor shaft 20, a rotor core 21, an upper plate 22, and a lower plate 23. The rotor shaft 20 is rotatably mounted relative to the housing 4 by bearings 21A and 21B.

[0020] The rotor core 21 is configured, for example, by laminating electromagnetic steel plates in the axial direction. The rotor core 21 is attached to the rotor shaft 20. The rotor core 21 rotates as a unit with the rotor shaft 20. A multitude of permanent magnets (not illustrated) are embedded in the rotor core 21.

[0021] The upper plate 22 and the lower plate 23 are annular plate elements arranged coaxially with the rotor shaft 20. The upper plate 22 and the lower plate 23 are attached to the rotor shaft 20. The rotor core 21 is held between them from the outside in the axial direction. The upper plate 22 and the lower plate 23 rotate as a unit with the rotor shaft 20 and the rotor core 21.

[0022] The stator 3 is attached to the inner surface of the housing 4 to cover the outer circumference of the rotor 2. The stator 3 includes a tubular stator core 30 and a stator coil 31. Like the rotor core 21, the stator core 30 is configured by laminating electromagnetic steel plates in the axial direction. A multitude of teeth is provided on the inner circumferential side of the stator core 30. The stator coil 31 is wound around the teeth.

[0023] The housing 4 accommodates the rotor 2 and the stator 3. The housing 4 encloses a cylindrical element 10, which has a cylindrical shape, a top section 11 for closing the upper opening of the cylindrical element 10, and a bottom section 13 for closing the lower opening of the cylindrical element 10. A space 40 for accommodating the rotor 2 and the stator 3 is formed within the housing 4 by the cylindrical element 10, the top section 11, and the bottom section 13. stator

[0024] Fig. Figure 3 is a perspective view of the stator 3 according to one embodiment. Fig. Figure 4 is a perspective view of the inner circumferential section of the stator 3 according to one embodiment. Fig. Figure 5 is a perspective view of a section to which a fastening section is attached, in a plurality of connection-side extension sections according to one embodiment.

[0025] With reference to Fig. 3, Fig. 4 to Fig. The stator 3 includes 5 together: a stator core 30 having a cylindrical shape and including a plurality of slots 30s arranged in a circumferential direction; the stator coil 31, which is inserted into each of the plurality of slots 30s, is wound around the stator core 30 and includes a plurality of terminal-side extension sections 32e, which extend outwards in the axial direction from a first end surface 30f1 of the stator core 30 and are arranged in the circumferential direction; and a fastening section 38 which is configured to fasten sections adjacent to each other in the circumferential direction in the plurality of connection-side extension sections 32e.

[0026] On the inner circumferential side of the stator core 30, a plurality of slots 30s and a plurality of teeth 30t are arranged alternately around the entire circumference. The plurality of slots 30s are arranged at equal intervals in the circumferential direction of the stator core 30. For example, insulating material may be provided in the slot 30s. The configuration (arrangement, number, shape, or the like) of the slot 30s can be modified according to design specifications.

[0027] In the present embodiment, the stator coil 31 consists of a plurality of segmented coils 39. For example, the segmented coil 39 is a flat wire with an insulating film formed by covering the outer circumference of the wire with an insulating film. The segmented coil 39 is not limited to the foregoing and can consist of a winding with a circular or elliptical cross-section. The configuration of the segmented coil 39 can be modified according to design specifications.

[0028] The stator coil 31 includes a first coil end 32 with a plurality of terminal-side extension sections 32e projecting axially from the first end surface 30f1 of the stator core 30, and a second coil end 33 projecting axially from the second end surface 30f2 on the side opposite the first end surface 30f1 of the stator core 30. The axial direction of the stator core 30 corresponds to a direction along the central axis CL (see Fig. 2) of the rotor shaft 20. The first end surface 30f1 of the stator core 30 corresponds to an upper end surface of the stator core 30. The second end surface 30f2 of the stator core 30 corresponds to a lower end surface of the stator core 30. In the stator core 30, the radial direction is a direction orthogonal to the axial direction, and the circumferential direction is a direction that circumscribes the central axis CL.

[0029] With reference also to Fig. In the present embodiment, the electric motor 1 includes the rotor 2, the stator 3, and a housing 4 for receiving the rotor 2 and the stator 3. The first coil end 32 is arranged axially on the side opposite (top side) to the bottom section 13 of the housing 4. Conversely, the second coil end 33 is arranged axially on the same side (bottom side) as the bottom section 13 of the housing 4. In the present embodiment, the plurality of connection-side extension sections 32e are arranged axially on the side opposite (top side) to the bottom section 13 of the housing 4.

[0030] The stator 3 of the present embodiment further includes power lines 35U, 35V, 35W, which are connected to the plurality of terminal-side extension sections 32e. The plurality of terminal-side extension sections 32e includes connecting extension sections 32j, to which the power lines 35U, 35V, 35W are connected, and non-connecting extension sections 32u, to which the power lines 35U, 35V, 35W are not connected. The power lines 35U, 35V, 35W each include a stranded wire and a terminal connected to the end section of the stranded wire. A power line connecting section 36 for connecting each of the power lines 35U, 35V, 35W is connected to the connecting extension section 32j. The power line connection section 36 is connected to the corresponding connection of the power lines 35U, 35V, 35W.

[0031] The power line connection sections 36 of the present embodiment are connected to the respective terminals of the power lines 35U, 35V, and 35W by screws and nuts. The configuration of the power lines 35U, 35V, and 35W and the power line connection sections 36 is not limited to the foregoing and can be modified according to design specifications. For example, the power lines 35U, 35V, and 35W can each include a busbar, and the busbar and the connection extension sections 32j can be welded together. Alternatively, the power lines 35U, 35V, and 35W can each include a stranded wire and a terminal connected to the end section of the stranded wire, and the terminal and the connection extension sections 32j can be welded together.For example, the power lines 35U, 35V and 35W can each include a stranded wire and a first connection connected to the end section of the stranded wire, and a second connection can be connected to the connection extension section 32j, and the first connection and the second connections can be welded together.

[0032] In the present embodiment, the stator coil 31 includes three-phase winding groups 34U1, 34U2, 34V1, 34V2, 34W1, and 34W2 connected in parallel. The three-phase winding groups 34U1, 34U2; 34V1, 34V2; 34W1, and 34W2 are U-phase, V-phase, and W-phase winding groups, respectively. The winding groups 34U1, 34U2, 34V1, 34V2, 34W1, and 34W2 of the U-phase, V-phase, and W-phase are arranged along the circumferential direction of the stator core 30 such that two windings of each phase (U-phase, U-phase; V-phase, V-phase; W-phase, W-phase) are arranged adjacent to one another.

[0033] In the present embodiment, the stator coil 31 comprises a plurality of segmented coils 39, each having a U-shape with interconnected end sections. The stator coil 31 is formed by winding a plurality of the segmented coils 39 in a wave-like fashion. Although the illustrated example demonstrates the segmented coil 39 with a square cross-section, a segmented coil 39 with a circular cross-section can also be used. The cross-sectional shape of the segmented coil 39 is not limited to the above and can be modified according to design specifications.

[0034] In the illustrated example, if a plurality of segmented coils 39 inserted in the circumferential direction of the stator core 30 are each designated as winding section 34A, 34B, 34C and 34D, then four winding sections 34A, 34B, 34C, 34D are arranged in the radial direction of the stator core 30. The four winding sections 34A, 34B, 34C and 34D comprise a first winding section 34A, a second winding section 34B, a third winding section 34C and a fourth winding section 34D, respectively. The first winding section 34A, the second winding section 34B, the third winding section 34C and the fourth winding section 34D are arranged in this order from the innermost circumference to the outermost circumference of the stator core 30.

[0035] Fig. Figure 6 is a view of a slot 30s of the stator 3 according to an embodiment, taken in a plane orthogonal to the axial direction.

[0036] With reference also to Fig. The segmented coils 39 are arranged in slot 30s to form a multitude of layers. Slot 30s encloses a multitude of layers L1 to L8, corresponding to different coil layers.

[0037] In the illustrated example, the multiple layers L1 to L8 are configured such that the first layer L1 to the eighth layer L8 are arranged in this order from the inner circumferential side in the radial direction (bottom side in the drawing). The first winding section 34A is inserted into the first layer L1 and the second layer L2. The second winding section 34B is inserted into the third layer L3 and the fourth layer L4. The third winding section 34C is inserted into the fifth layer L5 and the sixth layer L6. The fourth winding section 34D is inserted into the seventh layer L7 and the eighth layer L8. The number of layers is not limited to the above and can be changed according to design specifications.

[0038] Fig. Figure 7 is a view illustrating the segment coil 39 before mounting it on the stator core 30 according to one embodiment. Fig. Figure 8 is a view illustrating the segment coil 39 according to an embodiment after twisting formation.

[0039] With reference to Fig. 7 and Fig. 8 together the segment coil 39 is formed in a U-shape before being mounted on the stator core 30.

[0040] In particular, the segmented coil 39 includes a U-shaped section 39a, formed in a mountain-like shape (U-shape) projecting axially to one side, and two straight sections 39b1 and 39b2, extending linearly from each end of the U-shaped section 39a to the other side in the axial direction, parallel to each other. The U-shaped section 39a forms the second coil end 33. The straight sections 39b1 and 39b2 are sections to be inserted into the slot 30s, with the exception of the sections to be twisted. The segmented coil 39 has a shape such that, for example, in the first winding section 34A, the end of one straight section 39b1 is inserted into the first layer L1 and the end of the other straight section 39b2 is inserted into the second layer L2.

[0041] For example, after the segment coil 39 is inserted into the slot 30s, the first extension section 39c1 is twisted circumferentially at one end, and the second extension section 39c2 is twisted circumferentially at the other end. For example, the two segment coils 39 are connected at their end sections. The end section of the first extension section 39c1, after twisting one of the two segment coils 39, is connected to the end section of the second extension section 39c2, after twisting the other segment coil 39, by welding or the like. In each of the segment coils 39, the connecting section at the end of the first extension section 39c1 and the connecting section at the end of the second extension section 39c2 are arranged to be aligned radially.A neutral conductor 37N, consisting of a busbar or the like, is then connected by welding or the like to a predetermined section of the segmented coils 39. The extension sections 39c1 and 39c2 form the first coil end 32.

[0042] Fig. Figure 9 is a connection diagram of the stator coil 31 according to one embodiment.

[0043] With reference also to Fig. 9 The stator coil 31 is connected in a double star configuration. In the present embodiment, a first star configuration, which includes a U1 phase winding group 34U1, a V1 phase winding group 34V1 and a W1 phase winding group 34W1, and a second star configuration, which includes a U2 phase winding group 34U2, a V2 phase winding group 34V2 and a W2 phase winding group 34W2, are connected in parallel.

[0044] In the first star connection and the second star connection, components of each phase are electrically connected: in the U-phase, U1-phase winding group 34U1 and U2-phase winding group 34U2; in the V-phase, V1-phase winding group 34V1 and V2-phase winding group 34V2; in the W-phase, W1-phase winding group 34W1 and W2-phase winding group 34W2.

[0045] The phase winding groups (the U1 phase winding group 34U1, the V1 phase winding group 34V1 and the W1 phase winding group 34W1), which form the first star connection, and the phase winding groups (the U2 phase winding group 34U2, the V2 phase winding group 34V2 and the W2 phase winding group 34W2), which form the second star connection, are electrically connected by the neutral conductor 37N. The first star connection can be electrically connected by connecting the U1 phase winding group 34U1, the V1 phase winding group 34V1 and the W1 phase winding group 34W1 through a first neutral conductor 37N1 (not illustrated), and the second star connection can be electrically connected by connecting the U2 phase winding group 34U2, the V2 phase winding group 34V2 and the W2 phase winding group 34W2 through a second neutral conductor 37N2 (not illustrated). Fastening section

[0046] In the present embodiment, the fastening section 38 is an adhesive. For example, an epoxy adhesive or an organic adhesive can be used. The type of adhesive is not limited to the above and can be changed according to design specifications.

[0047] In the present embodiment, the adhesive has a viscosity high enough to prevent downward flow, even when applied circumferentially between adjacent sections of the terminal-side extension sections 32e. For example, the high-viscosity adhesive includes a two-component epoxy resin adhesive. The type of high-viscosity adhesive is not limited to the foregoing and can be modified according to design specifications.

[0048] For example, the high-viscosity adhesive is injected (applied) between sections in the connection-side extension sections 32e that are adjacent in the circumferential direction using a syringe (dispenser) or the like. The high-viscosity adhesive has low flowability and is easy to handle, allowing it to be precisely positioned at predetermined locations. The high-viscosity adhesive hardens as it cures, enabling the precise, gap-free fastening of predetermined positions.

[0049] In the present embodiment, the length AE (adhesive area) of the adhesive section along the connection-side extension section 32e is 10 mm or more. For example, by applying the adhesive between the adjacent sections of the connection-side extension section 32e in the circumferential direction in an application area DE (e.g. 20 mm or more), which is illustrated in the drawing, predetermined positions can be precisely fixed over a wide area.

[0050] In the present embodiment The plurality of connection-side extension sections 32e each includes a first connection extension section 32j1, a second connection extension section 32j2, which are connected to the power lines 35U, 35V, 35W, which are arranged adjacent to each other in the circumferential direction, and a non-connection extension section 32u, which is not connected to the power lines 35U, 35V, 35W. The fastening section 38 fastens at least one of the first connection extension section 32j1 or the second connection extension section 32j2 and the non-connection extension section 32u, excluding a section that is adjacent in the circumferential direction between the first connection extension section 32j1 and the second connection extension section 32j2.In the example illustrated in the drawing, the fastening section 38 does not fasten any circumferentially adjacent sections in the first connecting extension section 32j1 and the second connecting extension section 32j2. The fastening section 38 fastens circumferentially adjacent sections between each of the first connecting extension section 32j1 and the second connecting extension section 32j2, as well as the non-connecting extension section 32u.

[0051] In the present embodiment, sections of the plurality of terminal-side extension sections 32e, wherein the fastening sections 38 are attached, are arranged radially within the stator core 30. In the example illustrated in the drawing, sections of the plurality of terminal-side extension sections 32e, wherein the fastening sections 38 are attached, are arranged radially on the innermost side of the stator core 30. The fastening section 38 is located adjacent to the innermost surface in the radial direction of the plurality of terminal-side extension sections 32e and on mutually facing side surfaces.

[0052] In the present embodiment, each of the plurality of connection-side extension sections 32e includes an inclined section 32s that extends diagonally with respect to the axial and circumferential directions. The fastening section 38 secures the inclined sections 32s that are adjacent to each other in the circumferential direction within the plurality of connection-side extension sections 32e. In the illustrated example, the adhesive area AE and the application area DE are provided along the respective inclined sections 32s. Operation and impacts

[0053] As described above The stator 3 according to the present embodiment includes: including the stator core 30 with a cylindrical shape and the plurality of slots 30s arranged in the circumferential direction; the stator coil 31, which is inserted into each of the plurality of slots 30s, is wound around the stator core 30 and includes the plurality of terminal-side extension sections 32e, which extend axially outwards from the first end surface 30f1 of the stator core 30 and are arranged in the circumferential direction; and the fastening section 38, which is configured to fasten sections adjacent to each other in the circumferential direction in the plurality of connection-side extension sections 32e.

[0054] For example, if sections of the plurality of connection-side extension sections 32e are attached in a radial direction adjacent to each other, it is difficult to arrange the fastening section 38 between the sections in the radial direction, which leads to problems of deterioration of the ease of assembly and a reduction in the fastening strength.

[0055] On the other hand, according to the present embodiment, by fastening sections that are adjacent to each other in the circumferential direction of the plurality of connection-side extension sections 32e, it is possible to improve the ease of assembly, since it is simple to arrange the fastening section 38 between the sections in the circumferential direction. Additionally, it is possible to improve the fastening strength of sections that are adjacent to each other in the circumferential direction of the plurality of connection-side extension sections 32e. Thus, it is possible to improve both the ease of assembly and the fastening strength.

[0056] In the present embodiment, the fastening section 38 is an adhesive.

[0057] According to the present embodiment, predetermined sections can be attached without any gap by introducing the adhesive between the adjacent sections of the plurality of connection-side extension sections 32e in the circumferential direction.

[0058] In the present embodiment, the adhesive has a viscosity that is high enough to prevent the adhesive from flowing downwards, even when it is provided between the adjacent sections of the plurality of connection-side extension sections 32e in the circumferential direction.

[0059] According to the present embodiment, predetermined sections can be precisely attached without any gap by introducing the high-viscosity adhesive between the adjacent sections of the plurality of connection-side extension sections 32e in the circumferential direction.

[0060] In the present embodiment, the length AE of the adhesive section along the connection-side extension section 32e is 10 mm or more.

[0061] According to the present embodiment, the fastening strength is further improved by fastening the adjacent sections in the plurality of connection-side extension sections 32e to each other in the circumferential direction by 10 mm or more.

[0062] In the present embodiment, the stator 3 further includes the power lines 35U, 35V and 35W, which are connected to the terminal-side extension sections 32e.

[0063] According to the present embodiment, the fastening strength of the connection-side extension sections 32e, to which the power lines 35U, 35V and 35W are connected, can be improved. This can reduce the risk of breakage or the like in the connection section due to resonance of the power lines 35U, 35V and 35W during vehicle vibrations.

[0064] In the present embodiment The plurality of connection-side extension sections 32e each includes a first connection extension section 32j1 and a second connection extension section 32j2, which are connected to the power lines 35U, 35V, 35W and are circumferentially adjacent to each other, and a non-connection extension section 32u, which is not connected to the power lines 35U, 35V, 35W. The fastening section 38 fastens at least one of the first connection extension section 32j1 or the second connection extension section 32j2 and the non-connection extension section 32u, excluding a section that is circumferentially adjacent between the first connection extension section 32j1 and the second connection extension section 32j2.

[0065] According to the present embodiment, it is possible to further improve the ease of assembly and the strength of fastening by fastening the minimum required sections.

[0066] In the present embodiment, sections of the plurality of connection-side extension sections 32e, wherein the fastening sections 38 are fastened, are arranged inside the stator core 30 in the radial direction.

[0067] According to the present embodiment, the fastening section 38 is easily arranged from the inside of the radial direction of the stator core 30 to the section of the plurality of terminal-side extension sections 32e, wherein the fastening section 38 is fastened, thereby contributing to a further improvement in the ease of assembly.

[0068] In the present embodiment, each of the plurality of connection-side extension sections 32e includes an inclined section 32s that extends diagonally with respect to the axial and circumferential directions. The fastening section 38 fastens the inclined sections 32s that are adjacent to each other in the circumferential direction within the plurality of connection-side extension sections 32e.

[0069] According to the present embodiment, the fastening strength is further improved by fastening the inclined sections 32s, which are adjacent to each other in the circumferential direction of the plurality of connection-side extension sections 32e.

[0070] In the present embodiment, the stator coil 31 includes three-phase winding groups 34U, 34U2, 34V1, 34V2, 34W1 and 34W2, which are connected in parallel to each other.

[0071] According to the present embodiment, even when the parallel three-phase winding groups 34U, 34U2, 34V1, 34V2, 34W1 and 34W2 are provided, the ease of assembly and the strength of fastening can be improved.

[0072] In the present embodiment, the stator coil 31 includes a plurality of segment coils 39, each of which has a U-shape with interconnected end sections.

[0073] According to the present embodiment, even if the plurality of U-shaped segment coils 39, each having a U-shape with interconnected end sections, are used, the ease of assembly and the strength of fastening can be improved.

[0074] The electric motor 1 of the present embodiment includes the rotor 2, the stator 3, and the housing 4 for receiving the rotor 2 and the stator 3. The plurality of connection-side extension sections 32e are arranged on the side opposite the bottom section 13 of the housing 4 in the axial direction.

[0075] According to the present embodiment, the plurality of connection-side extension sections 32e can be accessed in the axial direction from the side opposite the bottom section 13 of the housing 4 (top side) (the fastening section 38 can be arranged in this way), which contributes to a further improvement in the ease of assembly. Example of changes

[0076] In the embodiment described above, the example with the fastening section as an adhesive was described, but such a limitation is not intended. For example, the fastening section can be, as in Fig. 10 and Fig. Figure 11 illustrates a resin sheet 138 coated with an adhesive. The resin sheet 138 can be provided on outer side surfaces in the radial direction of adjacent sections of the plurality of connection-side extension sections 32e in the circumferential direction. The resin sheet can have a rectangular parallelepiped shape spanning adjacent sections in the circumferential direction when viewed from the radial direction. The resin sheet can have a shape that provides a mounting surface (side surface) larger than the outer side surfaces in the radial direction of adjacent sections in the circumferential direction.

[0077] For example, the element to which the adhesive is applied is not limited to the foregoing and may be a plate other than a resin sheet, a foil-shaped element, or a sheet-shaped element. Although not illustrated, the fastening section may be a cord element (thread, binding tape, or the like) capable of joining adjacent sections of the plurality of connection-side extension sections circumferentially. The fastening section may be an impregnated element (sponge, cloth, fiber, or the like) impregnated with an adhesive. The fastening section may be a shaped element capable of fastening adjacent sections of the plurality of connection-side extension sections circumferentially.The fastening section can be a resin element capable of securing adjacent sections of the multiple connection-side extension sections circumferentially. In this case, for example, a molded resin element can be used. When fastening with a resin element, for instance, a molded E-shaped resin element can be inserted from the coil side to secure the coils together. The configuration of the fastening section can be modified according to the design specifications.

[0078] In the embodiment described above, the example was described in which the adhesive has a viscosity high enough to prevent downward flow, even when applied between adjacent sections of the plurality of connection-side extension sections in the circumferential direction, but such a restriction is not intended. For example, the adhesive may have a downward-flowing viscosity (low viscosity) when applied between sections that are adjacent to each other in the plurality of connection-side extension sections in the circumferential direction. The viscosity of the adhesive may be modified according to the design specifications.

[0079] In the embodiment described above, an example was presented in which the length of the adhesive section along the connection-side extension is 10 mm or more, but such a limitation is not intended. For example, the adhesive may have a length of less than 10 mm along the connection-side extension. The length of the adhesive along the connection-side extension can be modified according to the design specifications.

[0080] In the embodiment described above, the example was described in which the stator further encloses the power lines connected to the terminal extension sections, but such a limitation is not intended. For example, the power lines may not be connected to the terminal extension sections. For example, a neutral conductor may be connected to the terminal extension sections. For example, other components (busbar or the like) may be connected to the terminal extension sections. The installation configuration of the power lines can be modified according to the design specifications.

[0081] In the embodiment described above, the example described includes the following multiple connection-side extension sections: the first connection extension section and the second connection extension section, which are connected to the power lines and are adjacent to each other in the circumferential direction; and the non-connection extension section, which is not connected to the power lines, where The fastening section fastens at least one of the first connecting extension section or the second connecting extension section and the non-connecting extension section, except for a section that is adjacent in the circumferential direction between the first connecting extension section and the second connecting extension section.

[0082] However, no such restriction is intended. For example, the fastening section can fasten sections that are adjacent to each other circumferentially in the first connecting extension section and in the second connecting extension section. The fastening configuration of the fastening section can be modified according to the design specifications.

[0083] However, the embodiment described above depicts an example in which sections of the plurality of terminal-side extension sections, wherein the mounting sections are attached, are arranged inside the stator core in the radial direction, but such a restriction is not intended. For example, the section of the plurality of terminal-side extension sections, wherein the mounting section is attached, can be arranged outside the stator core in the radial direction. The arrangement configuration of the sections of the plurality of terminal-side extension sections, wherein the mounting sections are attached, can be modified according to the design specifications.

[0084] In the embodiment described above, the example was described with each of the plurality of connection-side extension sections including an inclined section extending diagonally with respect to the axial and circumferential directions, and the fastening section securing the inclined sections that are adjacent to each other in the circumferential direction in the plurality of connection-side extension sections, but such a restriction is not intended. For example, each of the plurality of connection-side extension sections may have a linear section along the axial direction, and the fastening sections may secure the linear sections that are adjacent to each other in the circumferential direction of the plurality of connection-side extension sections.The fastening configuration of the circumferentially adjacent sections of the multitude of connection-side extension sections can be modified according to the design specifications.

[0085] In the embodiment described above, the example includes a stator coil comprising three-phase winding groups connected in parallel, but such a limitation is not intended. For example, the stator coil can include three-phase winding groups connected in series. The configuration of the winding groups and the stator (pole, phase, slot ratio, or the like) can be modified according to the design specifications.

[0086] In the embodiment described above, the example with the stator coil included a plurality of segmented coils, each having a U-shape with interconnected end sections, but such a limitation is not intended. For example, the stator coil could include a continuously wound coil in a waveform. The configuration of the stator coil can be modified according to the design specifications.

[0087] In the embodiment described above, the example includes the electric motor, which comprises the rotor, the stator described above, and the housing for receiving the rotor and stator. The plurality of terminal-side extension sections is arranged on the side axially opposite the bottom section of the housing, but such a restriction is not intended. For example, the plurality of terminal-side extension sections can be arranged on the same side (the side opposite the opening section) as the bottom section of the housing in the axial direction. The configuration of the plurality of terminal-side extension sections can be modified according to the design specifications.

[0088] In the embodiment described above, the example described involved an electric motor mounted on an electric rotary excavator, and the description used an example of an electric rotary motor for rotating the upper rotating body of the electric rotary excavator, but such a limitation is not intended. For example, the electric motor could be mounted on other working machines, such as a wheel loader, bulldozer, or dump truck. For example, the electric motor could be configured as a drive motor for powering a working tool or as a drive motor for powering a travel device. The configuration of the working machine on which the electric motor is mounted and the object to be driven by the electric motor can be modified according to the design specifications.

[0089] In the embodiment described above, the example given is one in which the electric motor is arranged vertically so that the rotor shaft is parallel to the axis of rotation, but such a limitation is not intended. For example, the electric motor can be arranged horizontally so that the rotor shaft is perpendicular to the axis of rotation. For example, the electric motor can be inclined so that the rotor shaft intersects the axis of rotation at an angle. The configuration of the electric motor can be modified according to the design specifications.

[0090] In the embodiment described above, the example given is an internal rotor motor in which the stator is located outside a cylindrical rotor, but such a limitation is not intended. For example, the electric motor could be an external rotor motor in which the stator is located inside a cup-shaped rotor. The type of electric motor can be changed depending on the design specifications.

[0091] Although one embodiment has been described above with reference to the drawings, specific configurations are not limited to those described above, and configurations may be added, omitted, replaced and otherwise modified without departing from the spirit of the present disclosure, and embodiments described above may be combined in a suitable manner. Reference symbol list

[0092] 1 Electric motor, 2 Rotor, 3 Stator, 4 Housing, 13 Bottom section, 30 Stator core, 30f1 First end surface, 30s Slot, 31 Stator coil, 32e Terminal-side extension section, 32j1 First connection extension section, 32j2 Second connection extension section, 32u Non-connection extension section, 32s Inclined section, 34U1, 34U2, 34V1, 34V2, 34W1, 34W2, Winding group, 35 Power line, 38 Mounting section, 39 Segment coil, 100 Working machine, 114 Rotary motor, 120 Traveling body, 140 Upper rotating body, 160 Working device, AE Adhesive area (Length of adhesive along the terminal-side extension section) QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2023-201045

[0002] JP 2016-15797 A

[0004]

Claims

Stator comprising: a stator core having a cylindrical shape and including a plurality of slots arranged in a circumferential direction; a stator coil inserted into each of the plurality of slots, wound around the stator core and including a plurality of terminal-side extension sections extending axially outward from a first end surface of the stator core and arranged in the circumferential direction; and a fastening section configured to fasten circumferentially adjacent sections in the plurality of terminal-side extension sections. Stator according to claim 1, wherein the fastening section is an adhesive. Stator according to claim 2, wherein the adhesive has a viscosity that is high enough to prevent the adhesive from flowing downwards when it is provided between the adjacent sections of the plurality of terminal-side extension sections in the circumferential direction. Stator according to claim 2 or 3, wherein the length of the adhesive section along the plurality of connection-side extension sections is 10 mm or more. Stator according to one of claims 1 to 3, further comprising a current conductor connected to the extension section on the connection side. Stator according to claim 5, wherein the plurality of connection-side extension sections each includes: a first connecting extension section and a second connecting extension section, which are connected to the plurality of power lines and are adjacent to each other in the circumferential direction; and a non-connecting extension section, which is not connected to the plurality of power lines, the fastening section fastening at least one of the first connecting extension section or the second connecting extension section and the non-connecting extension section, except for a section which is adjacent between the first connecting extension section and the second connecting extension section in the circumferential direction. Stator according to one of claims 1 to 3, wherein the sections in which the fastening sections are fastened are arranged in the radial direction within the stator core of the plurality of terminal-side extension sections. Stator according to one of claims 1 to 3, wherein each of the plurality of terminal-side extension sections includes an inclined section which extends diagonally with respect to the axial direction and the circumferential direction, the fastening section fastening the inclined sections which are adjacent to each other in the circumferential direction in the plurality of terminal-side extension sections. Stator according to one of claims 1 to 3, wherein the stator coil comprises three-phase winding groups connected in parallel. Stator according to one of claims 1 to 3, wherein the stator coil comprises a plurality of segment coils, each of which has a U-shape with interconnected end sections. Electric motor comprising: a rotor; the stator according to any one of claims 1 to 3 and a housing configured to accommodate the rotor and the stator. Electric motor according to claim 11, wherein the plurality of connection-side extension sections is arranged on the side opposite the bottom section of the housing in the axial direction. Working machine comprising: a carriage; an upper rotating body rotatably mounted by the carriage about an axis of rotation; a working device operationally supported by the upper rotating body; and the electric motor according to claim 11, which is configured as a rotary motor for rotating the upper rotating body in relation to the carriage.

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