JP2014007782A - Electric motor - Google Patents

Abstract

An electric motor with improved weldability between flat coils is provided.
A through hole 10a is formed in the power distribution unit 10 so as to penetrate the stator side coil 7 of the stator unit 3. A power distribution side coil 11 is disposed in the through hole 10a. The stator side coil 7 is inserted from the inlet side opening 10a-1 of the through hole 10a, and is inserted from the outlet side opening 10a-2 through the opening 11a formed in the portion crossing the through hole 10a of the power distribution side coil 11. Protruding. Both coils are welded in a state where the tapered inner wall surface of the through-hole 10a presses and contacts the stator side coil 7 in the direction of the distribution side coil 11.
[Selection] Figure 4

Description

  The present invention relates to an electric motor in which a flat distribution-side coil and a flat stator-side coil are welded.

  An electric motor such as a three-phase synchronous AC motor creates a magnetic pole in the rotor by a permanent magnet on the stator side, and creates a magnetic pole in the stator teeth by a stator side coil arranged between the stator teeth. Then, the power distribution unit connected to the external power source switches the energization to the stator side coil and switches the S pole and the N pole of the stator teeth, thereby generating a rotational torque.

  Since the current supplied to the motor is a large current such as 250 Arms (maximum 500 A), a flat copper plate material (so-called rectangular wire) is employed for the stator side coil and the distribution side coil (for example, patents). References 1 and 2). The flat wire has a merit that the parts manufacturing cost is lower than that of the eccentric wire, and the assembly can be simplified.

When electrically connecting the flat stator side coil and the distribution side coil, welding (for example, Tungsten Inert Gas; TIG welding), which is a general method for joining metal members, is used.
Here, an outline of TIG welding will be described with reference to FIG. As shown in FIG. 6A, a flat stator side coil 100 and a similarly flat distribution side coil 101 are arranged in parallel, and the ends of both coils are TIG welded. FIGS. 6 (b) and 6 (c) are views taken along the arrow D showing the success of welding, and FIGS. 6 (d) to 6 (f) are views showing the failure of welding.

  When there is no gap between the stator side coil 100 and the power distribution side coil 101 as shown in FIG. 6B, welding is performed by the welding machine 102, so that the tips of both coils are shown in FIG. 6C. The whole melt | dissolves and the welding part 103 is formed, and the penetration allowance can fully be ensured. Therefore, the resistance between the coils is small, and good current can be supplied.

  On the other hand, when a gap is generated between the stator side coil 100 and the power distribution side coil 101 as shown in FIG. 6D, the TIG weldability becomes unstable, and as shown in FIG. Only one-side welding in a melted state occurs, or a poor penetration occurs as shown in FIG. In the one-side welding shown in FIG. 6E, the coils cannot be energized because the coils are not connected. In the case of poor penetration in FIG. 6 (f), since the penetration allowance is small, the cross-sectional area of the energized portion becomes small. For this reason, resistance between the coils increases to cause energization failure, or local heat generation increases, resulting in a decrease in motor efficiency or fusing of the welded portion 103.

JP 2008-79466 A JP 2002-186234 A

  When the electric motor of the above-mentioned patent document 1 performs welding between flat coils, both coils are inserted by inserting one end of the second coil into the opening in which one end of the first coil is disposed. Were facing each other in parallel. In the case of this configuration, there is a problem that a gap is generated between the coils depending on the degree of variation of each part, and the weldability becomes unstable.

  The electric motor of the above-mentioned patent document 2 is not a configuration in which flat coils are welded and electrically connected, but a configuration in which one coil is pressed against the other coil to ensure electrical connection. Specifically, a connection opening in which one end of the first coil is exposed is formed in the resin sealing the first coil, and one end of the first coil and a connection opening facing the connection opening are formed in the connection opening. A female portion into which one end portion of the second coil is inserted and connected is formed by the resin surface, and when the one end portion of the second coil is inserted, the second coil is connected to one end portion of the first coil. It was held between the resin surface of the opening. In the case of this configuration, since the first coil is in contact with the second coil at an angle, there is a problem that the contact area is small and the weldability becomes unstable.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electric motor having improved weldability between flat-plate coils.

  An electric motor according to the present invention includes a rotor unit integrated with a shaft, a stator unit fixed at a position surrounding the outer periphery of the rotor unit, and a plate-like stator side coil disposed in parallel to the axial direction of the shaft, and a stator A through hole that penetrates the end of the side coil, and a flat distribution side coil that is disposed parallel to the axial direction in the through hole, exposed from the through hole opening, and welded to the stator side coil that penetrates the through hole And a power distribution part that supplies power to the stator part via the power distribution side coil.The power distribution side coil is bent in the axial direction across the through hole, and the bent part is formed on the inner wall surface of the through hole. In addition to being disposed in contact with each other, an opening through which the stator side coil is inserted is formed at the through hole crossing portion, and the through hole has an opening area on the outlet side compared to the opening area on the inlet side of the stator side coil Is narrow, The inserted through stator side coil end portion to the mouth portion to the bent portion of the power distribution side coil is shaped to pressure contact.

  According to the present invention, the through-hole having a shape in which the outlet side is narrower than the inlet side of the stator side coil presses the stator side coil against the power distribution side coil. Thus, an electric motor with improved weldability can be provided.

It is sectional drawing which shows the structure of the electric motor which concerns on Embodiment 1 of this invention. It is a perspective view of a stator part and a power distribution part among the electric motors concerning Embodiment 1. FIG. It is a figure explaining rotation operation of the electric motor concerning Embodiment 1. FIG. It is sectional drawing which cut | disconnected the through-hole periphery of the power distribution part of Embodiment 1 along CC line shown in FIG. It is the perspective view which expanded the power distribution side coil among the electric motors which concern on Embodiment 1. FIG. FIGS. 6B and 6C are diagrams illustrating an outline of TIG welding, and FIGS. 6B and 6C are examples when welding is successful, and FIGS. 6D to 6F are examples when welding is failed.

Embodiment 1 FIG.
An electric motor 1 shown in FIGS. 1 and 2 constitutes a three-phase AC synchronous motor, and rotates a cylindrical housing 2, a stator unit 3 and a power distribution unit 10 fixed inside the housing 2, and a shaft (not shown). And a rotor portion 9 to be operated.

  The rotor portion 9 is formed with two protrusions protruding outward in the circumferential direction at intervals of 180 degrees, and the protrusions are shifted by 90 degrees in the middle of the rotation axis direction X (protrusions 9a and 9b). The rotor portion 9 may be composed of a permanent magnet. However, when the electric motor 1 is exposed to a high temperature, the magnetic properties deteriorate. For example, the magnetic steel sheet is punched out in a protruding shape, and the protruding portion is formed in the middle of the rotation axis direction X. The state is shifted by 90 degrees (protrusions 9a, 9b).

  By fixing the shaft to the rotor portion 9 and rotating the shaft integrally with the rotor portion 9, the rotational force generated in the rotor portion 9 is output to the outside. When the electric motor 1 is applied to an automobile turbocharger, an electric compressor, and the like, the shaft fixed to the rotor portion 9 is connected to a rotating shaft of a turbine (so-called impeller), and the electric motor 1 rotates the turbine.

  The stator portion 3 includes two stator cores 4 and 5, a magnet 6 disposed between the stator cores 4 and 5, six U-shaped stator side coils 7, and a mold portion 8 for integrating them. It consists of. Each of the stator cores 4 and 5 is configured by laminating electromagnetic steel plates in the rotation axis direction X. As shown in FIG. 2, the stator core 5 includes an annular body 5a and six protrusions (hereinafter referred to as teeth 5b) protruding from the inner peripheral portion of the annular body 5a toward the center. Although not visible in FIGS. 1 and 2, the stator core 4 is also composed of an annular body 4a and six teeth 4b. The magnet 6 has substantially the same shape as the annular bodies 4a and 5a.

  The stator side coil 7 is a one-turn coil obtained by bending a copper plate into a U shape. One stator side coil 7 is attached to one set of teeth 4b and 5b facing the rotation axis direction X. The mold portion 8 is formed of a resin member that integrally molds the stator cores 4 and 5, the magnet 6, and the stator side coil 7. Each stator side coil 7 mounted and molded on each of the teeth 4b, 5b penetrates the mold portion 8 in the rotation axis direction X, and a bent portion protrudes toward the stator core 4 and a tip portion protrudes toward the stator core 5 side. When the stator portion 3 is integrally molded, the tip portions of the stator side coils 7 are brought into contact with the inner wall of the mold and aligned in the height direction so that the heights of the tip portions of the stator side coils 7 are aligned. The shift in direction is suppressed.

  The power distribution unit 10 is formed of a resin member that integrally forms a power distribution side coil 11 of a copper plate. The distribution-side coil 11 is annularly arranged along the circumferential direction of the shaft, and has one end connected to the stator-side coil 7 and the other end connected to an inverter board (not shown). The power distribution unit 10 is formed with a through hole 10a for penetrating the tip end portion of the stator side coil 7. The stator side coil 7 penetrating the through hole 10a is arranged from the inside of the through hole 10a toward the opening. It faces the installed power distribution side coil 11 in parallel. Details of the through hole 10a will be described later.

  The inverter board connected to the distribution side coil 11 converts the external power source into an alternating current, and based on the position signal input from the position detection sensor 12, the three phases of the distribution side coil 11 of U phase, V phase and W phase are converted. The current is passed from the power distribution side coil 11 to the stator side coil 7 by sequentially switching. A position detection sensor 12 is installed at the center of the power distribution unit 10. The position detection sensor 12 detects the position of the target fixed to the shaft and outputs a position signal indicating the rotational position of the shaft.

Next, an outline of the operation of the electric motor 1 will be described.
The magnetic flux generated by the magnet 6 magnetized in the rotation axis direction X flows out from the teeth 4b of the stator core 4 arranged on the N pole side of the magnet 6 to the protrusion 9a of the rotor portion 9, and the rotor portion 9 moves in the rotation axis direction X. Then, the magnetic field flux exits from the protrusion 9b on the S pole side and flows into the teeth 5b of the stator core 5 disposed on the S pole side of the rotor portion 9. Thus, the magnetic field magnetomotive force of the magnet 6 acts on the rotor part 9, so that the protrusion 9 a of the rotor part 9 facing the N pole side of the magnet 6 is magnetized to the N pole, and the S pole of the magnet 6 The protrusion 9b of the rotor portion 9 facing the side is magnetized to the S pole.
FIG. 3 is a plan view of the stator unit 3 and the rotor unit 9 as viewed from the power distribution unit 10 side. However, the housing 2 and the stator side coil 7 are not shown. When a current flows through the U-shaped stator coil 7 via the distribution coil 11 of the distribution unit 10, the teeth 4b and 5b of the stator cores 4 and 5 are magnetized and rotated according to the direction of the flowing current. A magnetic field is generated and torque is generated. By sequentially switching the direction of the current flowing in the stator side coil 7, the NS polarities of the teeth 4b and 5b are rotated and moved as shown in FIGS. 9 rotates.

Next, the assembly procedure of the electric motor 1 will be described.
As shown in FIG. 1, the housing 2 is formed with an abutting portion 2 a that abuts on one end surface of the stator portion 3 and an abutting portion 2 b that abuts on one end surface of the power distribution unit 10. The integrally molded stator portion 3 is press-fitted into the housing 2 from the A direction and brought into contact with the contact portion 2a. Further, the integrally-distributed power distribution unit 10 is inserted into the housing 2 from the B direction, is brought into contact with the contact unit 2b, and is assembled with screws or the like. At this time, the front end portion of the stator side coil 7 is passed through the through hole 10a of the power distribution unit 10, the stator side coil 7 and the power distribution side coil 11 are arranged in parallel, and TIG welding is performed to electrically connect both coils. Connect to. In this electric motor 1, six stator side coils 7 are used, so there are two welded portions 13 per piece, for a total of 12 places.

  In the above description, the stator portion 3 in which the stator side coil 7 is molded is assembled to the housing 2, but the present invention is not limited to this assembly procedure. For example, when the stator part 3 is integrally formed, the stator side coil 7 is not molded, but instead, an insertion hole (not shown) for inserting the stator side coil 7 is formed in the molded part 8. And after attaching the stator part 3 to the housing 2, the stator side coil 7 is outsert in the insertion hole.

  Alternatively, when the housing 2 has no steps such as the contact portions 2a and 2b (not shown), the stator portion 3 and the power distribution portion 10 can be assembled from the same direction. In that case, first, the stator unit 3 is fixed to the power distribution unit 10, the tip of the stator side coil 7 is passed through the through hole 10 a of the power distribution unit 10, TIG welding is performed, and the stator side coil 7 and the power distribution side coil 11 are connected. Connect electrically. Then, the stator part 3 and the power distribution part 10 are inserted and fixed to the housing 2 from one direction.

Next, a method for welding the stator side coil 7 and the distribution side coil 11 will be described.
4 is a cross-sectional view of the periphery of the through hole 10a of the power distribution unit 10 cut along the CC line in FIG. 2, and FIG. 4 (a) shows a state before the stator side coil 7 is inserted into the through hole 10a. FIG. 4B shows the inserted state. 5A and 5B are perspective views for explaining the shape of the power distribution side coil 11. FIG. 5A shows a state before the stator side coil 7 is inserted into the opening 11a, and FIG. .

  As shown in FIG. 5, the power distribution side coil 11 is bent in an L shape, and an opening 11 a through which the stator side coil 7 is inserted is formed in the bent portion. When the distribution-side coil 11 that has been shaped is molded with a resin member to form the power distribution unit 10, the through hole 10a and the opening 11a are communicated with each other as shown in FIG. Accordingly, the distribution-side coil 11 is bent in an L shape across the through-hole 10a, and the bent portion is disposed in the rotational axis direction X in contact with the inner wall surface of the through-hole 10a. Project from 10a-2.

  The through hole 10a has a smaller opening area of the outlet side opening 10a-2 exposing the stator side coil 7 and the distribution side coil 11 than the opening area of the inlet side opening 10a-1 into which the stator side coil 7 is inserted. Yes. At this time, the inner wall surface on the side facing the stator side coil 7 is tapered so as to sag from the inlet side opening 10a-1 toward the outlet side opening 10a-2, and the stator side coil 7 is distributed by this inner wall surface. Press toward the side coil 11.

As shown in FIG. 4 (a), the stator side coil 7 is inserted into the through hole 10a from the inlet side opening 10a-1, inserted through the opening 11a of the power distribution side coil 11, and exposed from the outlet side opening 10a-2. To do. 4B, the inner wall surface on the outlet side opening 10a-2 side presses the stator side coil 7 against the bent portion of the distribution side coil 11 with the pressing force F, and the stator side coil 7 and A state in which the power distribution side coil 11 is in close contact with the gap is maintained. Further, when the pressing force F acts, the stator side coil 7 comes into contact with the edge 11b of the opening 11a, and this portion serves as a fulcrum and the tip portion of the stator side coil 7 bends in the direction of the distribution side coil 11. Adhesion is improved.
In this state, the end portions of the stator side coil 7 and the distribution side coil 11 are TIG welded to form a welded portion 13. As a result, the TIG weldability of the welded portion 13 is stabilized, and one-side welding and penetration failure do not occur, and good energization is possible.

  As described above, according to the first embodiment, the electric motor 1 is fixed at a position surrounding the outer periphery of the rotor portion 9 and the rotor portion 9 integrated with the shaft, and the plate-shaped stator side coil 7 is in the direction of the rotation axis of the shaft. The stator portion 3 disposed in parallel with X, the through hole 10a penetrating the end of the stator side coil 7, and the opening of the through hole 10a disposed in the through hole 10a in parallel with the rotation axis direction X. A stator-side coil 7 that is exposed and penetrates the through-hole 10a and a welded plate-like distribution-side coil 11; and a power-distribution unit 10 that supplies power to the stator unit 3 through the distribution-side coil 11. The distribution-side coil 11 is bent in the rotation axis direction X across the through-hole 10a, and the bent portion is disposed in contact with the inner wall surface of the through-hole 10a, and a portion that crosses the through-hole 10a. And An opening 11a through which the data-side coil 7 is inserted is formed, and the through-hole 10a has a narrower outlet-side opening 10a-2 than the inlet-side opening 10a-1 of the stator-side coil 7, and is inserted into the opening 11a. The end portion of the stator side coil 7 is configured to be pressed into contact with the bent portion of the distribution side coil 11. For this reason, since the through-hole 10a having a shape in which the outlet side opening 10a-2 is narrower than the inlet side opening 10a-1 of the stator side coil 7 makes the stator side coil 7 press contact with the distribution side coil 11, both It is possible to provide the electric motor 1 that can be welded in a state in which the coils are in close contact with each other with no gap, and the weldability is improved.

  In the present invention, within the scope of the invention, any combination of the embodiments, or any modification of any component in each embodiment, or omission of any component in each embodiment is possible. .

  DESCRIPTION OF SYMBOLS 1 Electric motor, 2 Housing, 2a, 2b Contact part, 3 Stator part, 4,5 Stator core, 4a, 5a Annulus, 4b, 5b Teeth, 6 Magnet, 7 Stator side coil, 8 Mold part, 9 Rotor part, 9a , 9b Salient pole, 10 Distribution part, 10a Through hole, 10a-1 Inlet side opening, 10a-2 Outlet side opening, 11 Distribution side coil, 11a opening part, 11b Edge, 12 Position detection sensor, 13 Welded part, 100 Stator Side coil, 101 Distribution side coil, 102 Welding machine, 103 Welded part

Claims (1)

A rotor unit integrated with the shaft;
A stator portion fixed at a position surrounding the outer periphery of the rotor portion, and a plate-like stator side coil disposed parallel to the axial direction of the shaft;
A through hole that penetrates the end of the stator side coil, and a flat plate that is disposed parallel to the axial direction in the through hole and exposed from the through hole opening and welded to the stator side coil that penetrates the through hole A power distribution side coil, and a power distribution unit that supplies power to the stator unit via the power distribution side coil,
The distribution-side coil is bent in the axial direction across the through-hole, and the bent portion is disposed in contact with the inner wall surface of the through-hole. An opening for inserting the stator side coil is formed,
The through-hole has a smaller opening area on the outlet side than the opening area on the inlet side of the stator-side coil, and presses the end of the stator-side coil inserted through the opening to the bent portion of the distribution-side coil. An electric motor having a shape to be brought into contact with.

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