JP3564992B2 - Stator core of resin mold motor and method of manufacturing stator - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a resin-molded electric motor having a printed wiring board for electrically connecting a winding wound around a stator core to a lead wire, and molding the stator core and the winding with an insulating resin. The present invention relates to a method for manufacturing a stator core and a stator.
[0002]
[Prior art]
The above-described resin-molded electric motor has a configuration as shown in, for example, Japanese Utility Model Laid-Open No. Hei 6-77458. That is, as shown in FIG. 4, the stator 2A includes a stator core 1A formed by laminating a plurality of ring-shaped cores 3 of the same shape and size, and a winding wound around the stator core 1A. 5 and a printed wiring board 7 arranged in the stacking direction of the stator core 1A for electrically connecting the winding 5 to the lead wire 6, and the outer periphery of the printed wiring board 7 is 7 is molded with an insulating resin 9 except for the soldering surface 8 on the soldering side. On the center line of the stator 2A, a rotating shaft 27 is rotatably supported by bearings 28. A rotating yoke 29 is fitted to the rotating shaft 27, and a rotor core 30 integrated with the rotating yoke 29 is provided. It is opposed to the stator core 1A while holding a gap.
[0003]
Conventionally, the molding of the stator 2A of the resin-molded electric motor with the insulating resin 9 for the stator 2A is performed using a resin mold 13 separated into a fixed mold 11 and a movable mold 12 as shown in FIG. It has been. The movable side mold 12 of the resin mold 13 has a reference surface 15 on which a stator (hereinafter also referred to as a workpiece) 14A as an assembly before molding is formed. 17 are provided on the end face. The fixed-side mold 11 is provided with a projection 19 for forming the other bearing holding portion 16 and a holding surface 20 which is on one side of the printed wiring board 7. A molding space 22 that forms the outer periphery of the mold portion of the stator 2A is formed in the resin mold 13 that has been molded on the mating surface 21.
[0004]
Before molding, the stator 14A has the stator core 1A covered at both ends with a core insulating material 23, the winding 5 is wound thereon, and the stator 14A is wound around a pin 24 implanted at one end of the core insulating material 23. In this embodiment, the terminal of the wire 5 is tied, and the printed wiring board 7 is placed on the end face of the core insulating material 23 and soldered. The work 14A is inserted into the molding space 22 of the movable mold 12 until the reference surface 18 of the stator core 1A on the side opposite to the printed wiring board contacts the reference surface 15 of the movable mold 12. Then, the movable mold 12 is moved to the fixed mold 11 together with the work 14A, and the insulating resin is molded from the injection port 25 in a state where the fixed mold 11 and the movable mold 12 are fitted on the mating surface 21. The work 14A is injected into the space 22 and subjected to a molding process. When the fixed mold 11 and the movable mold 12 are opened and taken out after a cooling period, the stator 2A molded with the insulating resin 9 is obtained.
[0005]
[Problems to be solved by the invention]
In the conventional stator 2A of the resin-molded electric motor as described above, the insulating resin 9 often reaches the soldering surface 8 of the printed wiring board 7 and adheres there, which often hinders soldering. There was a problem of getting up. The reason is that the dimension from the reference surface 15 of the resin mold 13 to the holding surface 20 that hits the printed wiring board 7 is larger than the dimension from the reference surface 18 of the work 14A to the soldering surface 8 of the printed wiring board 7. That is. That is, as shown in FIG. 5, the distance P at which the soldering surface 8 of the printed wiring board 7 is held in the resin mold 13 is equal to the thickness L of the stator core 1A from the reference surface 15 and the core insulating material. 23 is the total distance (P = L + A + B) of the height A of 23 and the thickness B of the printed wiring board 7.
[0006]
The variation in the thickness of each iron core 3 is large, and the greater the number of laminations, the greater the variation in the value of the stack thickness L, and the size of the resin mold 13 is determined in anticipation of the maximum change. Most of the dimensions of the resin mold 13 are larger than the dimensions of the work 14A. The reason for determining the dimensions of the resin mold 13 in consideration of the maximum amount of change is that if the distance P of the resin mold 13 becomes shorter than the distance P of the work 14A, the printed wiring board 7 will Is applied, and the printed wiring board 7 is broken.
[0007]
The present invention has been made in order to solve the above-mentioned conventional problems, and an object of the present invention is to reduce the variation in the distance from the reference surface of the resin mold to the printed wiring board even when the number of laminations increases. The development of a stator core for a resin-molded electric motor that can be made smaller and less likely to cause cracks in the printed wiring board and hinder soldering. It is an object of the present invention to develop a method of manufacturing a stator for a resin-molded electric motor, which can reduce the above-mentioned problems.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, an invention according to claim 1 includes a stator core configured by laminating a plurality of ring-shaped cores each having a groove on an outer periphery, a winding wound around the stator core, and a winding. And a printed wiring board disposed in the stacking direction of the stator core for electrically connecting the wires to the lead wires. A resin-molded motor that is molded with insulating resin while leaving the surface of the printed circuit board The reference surface that makes contact with the stator core before molding on the stator core before molding in the stator of the electric motor A means constituted by an iron core on the side closer to is adopted.
[0009]
In order to achieve the above object, a second aspect of the present invention is the above-described means, wherein the inner diameter of the iron core except for a few of the iron cores on the side close to the printed circuit board is increased, and the step in which the inner diameter changes A means for forming a reference plane by means of a section is adopted.
[0010]
In order to achieve the above object, a third aspect of the present invention is to reduce the outer diameter of the core according to the first aspect except for a few of the iron cores on the side close to the printed circuit board, and the outer diameter varies. A means for forming a reference surface with a stepped portion is adopted.
[0011]
In order to achieve the above object, an invention according to claim 4 includes a stator core configured by laminating a plurality of ring-shaped cores each having a groove on an outer periphery, a winding wound around the stator core, and a winding. And a printed wiring board disposed in the stacking direction of the stator core for electrically connecting the wires to the lead wires. When manufacturing the stator of a resin-molded electric motor molded with insulating resin while leaving the surface of the resin, the stator core before molding with insulating resin is brought into contact with the reference surface, which is the reference when inserting the resin mold. The reference surface is constituted by the iron core on the side close to the printed wiring board, and the insulating resin is set such that the reference surface and the surface to be soldered of the printed wiring board are in contact with the surface on the molding space side of the resin mold. Into the molding space To adopt a means of molding Te.
[0012]
In order to achieve the above object, the invention according to claim 5 is characterized in that, in the means according to claim 4, the inner diameter of the iron core except for a few on the side close to the printed circuit board is increased, and the step in which the inner diameter changes is formed. A means for forming a reference plane by means of a section is adopted.
[0013]
In order to achieve the above object, the invention according to claim 6 is characterized in that the outer diameter of the iron core in the means according to claim 4 is reduced except for a few of the iron cores on the side close to the printed circuit board, and the outer diameter varies. A means for forming a reference surface with a stepped portion is adopted.
[0014]
In order to achieve the above object, the invention according to claim 7 is based on the means according to claim 4, except that a few of the iron cores on the side close to the printed wiring board are located at positions where the windings of the stator core are not wound. And a means for forming a reference surface with the bottom of the hole.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings.
Embodiment 1 FIG.
Embodiment 1 shown in FIG. 1 relates to a method for manufacturing a stator core 1 and a stator 2 of a resin mold electric motor. The stator 2 is wound around a stator core 1 formed by laminating a plurality of ring-shaped cores 3 and 4 having a groove (not shown) on the outer periphery, and a groove of the stator core 1. And a printed wiring board 7 arranged in the stacking direction of the stator core 1 for electrically connecting the winding 5 to the lead wire 6. The printed wiring board 7 is molded with the insulating resin 9 except for the soldering surface 8 on the side to be soldered.
[0016]
A rotating shaft (not shown) is rotatably supported by bearings on the center line of the stator 2, a rotating yoke is fitted to the rotating shaft, and a rotor core integrated with the rotating yoke is attached to the stator core 1. The resin-molded electric motor is configured to be opposed to each other while maintaining the air gap. The lead wire 6 is electrically connected directly to the winding 5 or indirectly via a capacitor (not shown), and is soldered to the soldering surface 8 of the printed wiring board 7. The stator 2 has a feature in the stator core 1 except for a few cores 4 on the side close to the printed circuit board 7 among the cores 3 and 4 constituting the stator core 1. An inner diameter is configured to be large, and a step portion 10 whose inner diameter changes is configured.
[0017]
Molding of the stator 2 of the resin-molded electric motor having such a configuration with the insulating resin 9 is performed by using a resin mold 13 separated into a fixed mold 11 and a movable mold 12 as shown in FIG. The child 2 is manufactured. On the movable mold 12 of the resin mold 13, a reference surface 15 on which a stator (hereinafter also referred to as a work) 14 as an assembly before molding is provided, and a projecting portion for molding one bearing holding portion 16. 17 are provided on the end face. As shown in FIG. 1, the reference surface 15 comes into contact with a reference surface 18 formed by the step portion 10 of the stator core 1 when the work 14 is molded. The fixed-side mold 11 is provided with a projection 19 for forming the other bearing holding portion 16 and a holding surface 20 that contacts the soldering surface 8 of the printed wiring board 7. A molding space 22 (filled with the insulating resin 9 in the figure) is formed in the resin mold 13 that has been molded on the mating surface 21 and forms an outer contour of the mold portion of the stator 2.
[0018]
In the stator 14 before molding, both ends of the stator core 1 are covered with an iron core insulating material 23 formed of an insulating resin, the winding 5 is wound thereon, and implanted at one end of the one core insulating material 23. In this embodiment, the terminal of the winding 5 is wound around the pin 24, and the printed wiring board 7 is placed on the end surface of the core insulating material 23 and soldered. The workpiece 14 is inserted into the molding space 22 of the movable die 12 until the reference surface 18 formed by the step 10 of the stator core 1 abuts the reference surface 15 of the movable die 12, The movable mold 12 is moved together with the movable mold 12 to the fixed mold 11, and in a state where the fixed mold 11 and the movable mold 12 are joined together at the mating surface 21, the insulating resin is injected from the injection port 25 into the molding space 22. To mold the work 14. If the fixed mold 11 and the movable mold 12 are opened and taken out after a certain cooling period, the stator 2 molded with the insulating resin 9 can be manufactured.
[0019]
The distance Q at which the soldering surface 8 of the printed wiring board 7 of the work 14 is held in the resin mold 13 in the mold-clamped state is the thickness M of the iron core 4 having a small inner diameter of the stator core 1 from the reference surface 15. And the total distance (Q = M + A + B) of the height A of the core insulating material 23 and the thickness B of the printed wiring board 7. The variation in the thickness of each of the cores 3 and 4 is large, and the greater the number of stacked layers, the greater the variation in the overall thickness value. Therefore, the thickness M of the iron core 4 having a small inner diameter becomes much smaller than the conventional one, and the distance Q becomes shorter. Accordingly, when the workpiece 14 is set with the reference surface 18 facing the reference surface 15 of the resin mold 13, the variation in the distance Q from the reference surface 15 to the soldering surface 8 of the printed wiring board 7 includes the inner diameter. Does not include the variation in the thickness of the iron core 3 having a large value. In other words, only the variation of the stack thickness of the iron cores 4 having a small inner diameter affects the position of the printed wiring board 7 at the time of molding, so that the insulating resin 9 reaches the soldering surface 8 of the printed wiring board 7. Also, the printed wiring board 7 is less likely to be adhered to the printed wiring board 7 and the printed wiring board 7 is less likely to be broken when the mold is matched. Therefore, the productivity and quality of the stator 2 of the resin mold electric motor can be improved.
[0020]
Here, the number of the iron cores 4 having a small inner diameter is selected as small as possible as long as the stress applied to the iron cores 4 at the time of molding can be determined, or the movable mold 12 and the fixed mold 11 are combined. At the time, the gap between the soldering surface 8 of the printed wiring board 7 and the holding surface 20 of the fixed mold 11 formed by the variation of the distance P shown in the section of the prior art is used to elastically deform the iron core 4 having a small inner diameter. What is necessary is just to determine as the number which can be absorbed.
[0021]
Embodiment 2 FIG.
The second embodiment shown in FIG. 2 also relates to a method of manufacturing a stator core and a stator of a resin-molded electric motor similarly to the first embodiment, and has the same basic configuration as the first embodiment. Therefore, the same reference numerals are used for the same parts as in the first embodiment, and the description thereof is omitted.
[0022]
The stator 2 of the second embodiment shown in FIG. 2 has a small outer diameter except for some of the cores 3, 4 of the stator core 1 on the side closer to the printed wiring board 7, The reference surface 18 is formed on the outer peripheral portion of the stator core 1 by the step portion 10 whose outer diameter changes. A reference surface 15 is also provided at a position corresponding to the movable mold 12. By forming the reference surface 18 on the outer peripheral portion in this way, the area of the reference surface 18 can be made large and a stable reference can be obtained. Other configurations and manufacturing methods are the same as those of the first embodiment, and the same operation and effects as those of the first embodiment can be obtained. When there is a limit on the outer diameter, the shape of the step portion 10 may be changed within the limit.
[0023]
Embodiment 3 FIG.
Embodiment 3 shown in FIG. 3 also relates to a method of manufacturing a stator core and a stator of a resin-molded electric motor, similarly to Embodiment 1, and has the same basic configuration as Embodiment 1. Therefore, the same reference numerals are used for the same parts as in the first embodiment, and the description thereof is omitted.
[0024]
The stator 2 according to the third embodiment shown in FIG. 3 includes, at an arbitrary position where the winding 5 of the stator core 1 is not wound, the number of the cores 4 on the side closer to the printed circuit board 7 among the cores 3 and 4. Except for a single piece, a hole 26 penetrating the other iron core 3 is provided, and the bottom of the hole 26 forms the reference surface 18. The movable side mold 12 is also provided with a reference surface 15 which protrudes into the hole 26 and abuts against the reference surface 18 at a position corresponding thereto. By forming the reference surface 18 within the radial thickness of the stator core 1 in this manner, a stable reference can be created without being restricted by the inner and outer diameters of the stator core 1. Other configurations and manufacturing methods are the same as those of the first embodiment, and the same operation and effects as those of the first embodiment can be obtained.
[0025]
【The invention's effect】
As is apparent from the above description of the embodiment, according to the first, second and third aspects of the present invention, even when the number of stacked layers increases, the printed wiring board is not moved from the reference surface of the resin mold. Thus, it is possible to obtain a stator core of a resin-molded electric motor, which can reduce the variation in the distance to the printed wiring board and reduce the risk of breaking the printed wiring board and hindering the soldering.
[0026]
According to each of the fourth, fifth, sixth, and seventh aspects of the present invention, it is possible to produce a stator for a resin-molded electric motor, which can reduce breakage of a printed wiring board and hindrance to soldering. A good production method can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a stator during a molding process and a resin mold according to a first embodiment.
FIG. 2 is a cross-sectional view showing a stator during a molding process and a resin mold according to a second embodiment.
FIG. 3 is a cross-sectional view showing a stator during a molding process and a resin mold according to a third embodiment.
FIG. 4 is a sectional view showing a conventional resin mold electric motor.
FIG. 5 is a cross-sectional view showing a stator during a molding process of a conventional resin-molded electric motor together with a resin-molding mold.
[Explanation of symbols]
1 stator core, 2 stator, 3 core, 4 iron core, 5 winding, 6 lead wire, 7 printed wiring board, 8 soldering surface, 9 insulating resin, 10 stepped portion, 13 resin mold, 15 reference surface , 18 reference surface, 20 holding surface, 22 molding space, 26 holes.

Claims (7)

A stator core configured by laminating a plurality of ring-shaped cores having grooves on the outer periphery, a winding wound on the stator core, and electrically connecting the winding to a lead wire. And a printed wiring board arranged in the stacking direction of the stator core, and molding the outer periphery of the printed circuit board with an insulating resin except for a surface of the printed wiring board to which the lead wires are to be soldered. The stator core before molding in the stator of the resin-molded electric motor to be formed has a reference surface that is in contact with a reference surface serving as a reference when the resin mold is inserted by the core near the printed wiring board. A stator core for a resin-molded electric motor. The stator core of the resin-molded electric motor according to claim 1, wherein the inner diameter of the core except for a few of the iron cores on the side closer to the printed wiring board is configured to be large, and the reference surface is formed by a step portion whose inner diameter changes. A stator core of a resin-molded electric motor, characterized in that: The stator core of the resin-molded electric motor according to claim 1, wherein an outer diameter of the iron core is reduced except for a few of the iron cores on a side close to a printed wiring board, and the outer diameter is changed by a stepped portion. A stator core for a resin-molded electric motor, characterized by comprising a reference surface. A stator core configured by laminating a plurality of ring-shaped cores having grooves on the outer periphery, a winding wound on the stator core, and electrically connecting the winding to a lead wire. And a printed wiring board arranged in the stacking direction of the stator core, and molding the outer periphery of the printed circuit board with an insulating resin except for a surface of the printed wiring board to which the lead wires are to be soldered. In manufacturing the stator of the resin-molded electric motor, the stator core before being molded with the insulating resin is provided with a reference surface that is in contact with a reference surface serving as a reference when a resin mold is inserted into the printed wiring board. And the surface to be soldered of the printed wiring board is brought into contact with the surface on the molding space side of the resin mold so that the insulating resin is formed in the molding space. Inject Method for manufacturing a stator of the resin mold motor, characterized in that the mold. 5. The method of manufacturing a stator for a resin-molded electric motor according to claim 4, wherein the inner diameter of the iron core is increased except for a few of the iron cores on the side closer to the printed wiring board, and the stepped portion having a changed inner diameter is formed. A method for manufacturing a stator of a resin-molded electric motor, comprising a reference plane. 5. The method for manufacturing a stator of a resin-molded electric motor according to claim 4, wherein the outer diameter of the iron core is reduced except for a few of the iron cores on the side closer to the printed wiring board, and the stepped portion in which the outer diameter changes is provided. A method for manufacturing a stator of a resin-molded electric motor, comprising: The method for manufacturing a stator of a resin-molded electric motor according to claim 4, wherein the stator core is penetrated to a position where the winding of the stator core is not wound, except for some of the cores on the side close to the printed circuit board. A method for manufacturing a stator of a resin-molded electric motor, wherein a hole is provided, and a bottom surface of the hole forms a reference surface.

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