JPH0448119Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a stator for an electric motor having a stator body molded with a molding material.

[Technical background of the invention]

Conventionally, in the stator of this type of electric motor, when the stator body is molded with a molding material to make the stator body moisture-proof, it is done as shown in FIG. 6, for example. In FIG. 6, 1 is a stator main body, which has a stator core 2, a cylindrical body 3, flanges 4 and 5 at both ends, and a coil 6 wound around the outer periphery of the body 3. In this case 4
The bobbins 7 (only two are shown in the figure) are fitted and mounted in an annular arrangement. Reference numerals 8 and 9 denote a lower mold and an upper mold forming a mold, and a cavity 10 having a predetermined shape corresponding to the stator main body 1 is formed between these molds. With the stator body 1 housed in the cavity 10 between the lower mold 8 and the upper mold 9, a molding material 11 made of, for example, resin is injected into the cavity 1 from an injection machine 12 through a gate 13.
Then, the stator body 1 is molded with this molding material 11.
In this case, both the inner and outer flanges 4 and 5 of the bobbin 7
A predetermined gap is set within the cavity 10 between the inner wall surface of the cavity 10 and the outer surface of the flanges 4 and 5 so that the outer surface of the mold material 11 is also molded.

[Problems with background technology]

However, with the above configuration, when the mold material 11 is injected into the cavity 10, the inside of the cavity 10 becomes a high temperature atmosphere and the injection pressure of the mold material 11 is applied to the stator body 1. Of the inner and outer flanges 4 and 5 of the bobbin 7, the inner flanges 4 in particular may deform inward as shown in the figure, and may be molded in that deformed state. In this case, residual stress may be generated inside the mold material 11 due to the deformation of the bobbin 7, and the wall thickness of the mold material 11 may become thinner, which may cause cracks in the mold material 11. There was a risk that the moisture resistance would be impaired. Further, the coil 6 wound around the bobbin 7 is deformed due to the deformation of the bobbin 7, and there is also a problem that the coil 6 may be disconnected or layered.

[Purpose of invention]

The present invention has been made in view of the above circumstances, and its purpose is to provide a stator for an electric motor that can prevent deformation of the bobbin and coils when molding the stator body with a molding material, and that can be molded reliably. be.

[Summary of the idea]

In order to achieve the above-mentioned object, the present invention has a structure in which, at the inner flange of both flange parts of each bobbin attached to the stator core in an annular arrangement, at both ends corresponding to the inner flange part of the adjacent bobbin, The structure is such that a protrusion is formed on each inner flange of the corresponding mating side to prevent inward deformation, and when the stator body is molded with a molding material, the protrusion prevents the inside of the bobbin from being deformed. It is characterized in that it prevents deformation of the flange and, in turn, deformation of the coil wound around the bobbin.

[Example of idea]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. First, in FIGS. 1 and 2, 21 is a stator main body, and 22 is a stator core thereof. This stator core 22 is composed of a rectangular annular yoke core 23 and a magnetic pole core 24 arranged on the inner circumference of this yoke core 23. There is. Among these, the magnetic pole core 24 has a hole 25 for a field space in which a rotor (not shown) is arranged in the center, and magnetic pole parts 26 that also serve as bobbin mounting parts at four locations on the outer periphery. The tip of the magnetic pole part 26 is fitted into the yoke core 23. Reference numeral 27 designates a plurality of bobbins, in this case four bobbins, each having the same structure, and as shown in FIG. In the stator core 22, before the magnetic pole core 24 is fitted to the yoke core 23, each body part 28 is fitted and attached to each magnetic pole part 26 of the magnetic pole core 24, and the four bodies are attached to the stator core 22 in a rectangular shape. They are arranged in a ring. Here, in each bobbin 27, a rectangular first protrusion 3 is provided at each corner of the end of the inner flange 29 among the flange portions 29 and 30, as shown in FIG.
1 and 31 at one diagonal position, and the L-shaped second
The protrusions 32, 32 are respectively formed at the other diagonal position different from the above-mentioned diagonal position. Moreover, the first protrusion 31 among these first and second protrusions 31 and 32
A coil lead wire connection terminal 33 is held on one side of the coil lead wire connection terminal 33. Thus, when each bobbin 27 is arranged in a rectangular annular shape on the stator core 22, the first protrusion 31 of each inner flange 29 is connected to the mating bobbin 27.
The second protrusion 32 faces the first protrusion 31 of the mating bobbin 27 with a slight gap therebetween. In this case, the gap is
It is set to 0.1-1.5mm. A coil 34 is wound around the outer circumference of the body 28 of each bobbin 27, and each lead wire 34a is connected to the first coil of each bobbin 27.
It is connected to the coil lead wire connection terminal 33 of the protrusion 31 . The stator core 22, bobbin 27, and coil 34 constitute the stator body 21. On the other hand, in Figure 2, 3
5 and 36 are a lower mold and an upper mold that constitute a mold,
A cavity 37 having a predetermined shape corresponding to the stator body 21 is formed between them, and the stator body 21 is housed within this cavity 37. Here, the central convex portion 35a of the lower mold 35 has a cylindrical shape corresponding to the field space hole 25 of the stator body 21, and the central convex portion 36a of the upper mold 36 has a first As shown by the two-dot chain line in the figure, it has a cylindrical shape whose diameter is slightly larger than the tip of the protrusion 35a of the lower mold 35, and the tips of the protrusions 35a and 36a are in contact with each other.
Reference numeral 38 denotes a molding material made of, for example, a resin, which is injected into the cavity 37 from an injection machine 39 through a gate 40, and the stator main body 21 is molded with this molding material 38. In addition, in FIG. 2, the protrusions 31 and 32 indicated by broken lines are shown for convenience as seen transparently from the direction of line A--A in FIG. 1.

When molding the stator body 21 with the molding material 38 in the above configuration, the stator body 21 is first set in a state housed in the cavity 37 between the lower mold 35 and the upper mold 36, and then,
A molten molding material 38 is injected into the cavity 37 from an injection machine 39 through a gate 40 . At this time, the convex portions 35a, 3 of the lower mold and upper mold 35, 36
A molding material 38 is filled in the space formed by the outer surface of the mold 6a and the inner surface of the cavity 37 formed in the lower and upper molds 35 and 36, so that the stator main body 21 is formed into the hole 25 for the field space. The entire area except for is covered with mold material 38 (mold material 38
For convenience, the area covered by this is indicated by double-dashed diagonal lines in FIG. 1). Then, the mold material 38 is solidified. Here, during this molding, the inner flange 29 of each bobbin 27 in the stator main body 21 is
tend to deform inwardly under the injection pressure of the molding material 38, but since the first protrusion 31 of each inner flange 29 and the opposing second protrusion 32 come into contact with each other, Inward deformation of adjacent inner flange portions 29 is prevented. Therefore, since the inner flange 29 of each bobbin 27 is not molded with the molding material 38 while being deformed, the molding material 38
Residual stress due to deformation of the bobbin is not generated inside the bobbin, and there is no problem of thinning of the mold material 38, and as a result, the possibility of cracks occurring in the mold material 38 can be eliminated. Also, bobbin 27
Coil 3 is wound around this because it does not deform.
There is no risk of deformation of the coil 34, and there is no risk of wire breakage or layer shortening occurring in the coil 34. Therefore, the stator body 21 can be reliably molded using the molding material 38.

Incidentally, after the mold material 38 is solidified, the lower mold and the upper mold 35, 36 are opened. In this case, each bobbin 27 in the stator main body 21
Since the periphery of the mold material 38 and the surrounding portions of the protrusions 31 and 32 are all covered with the molding material 38, even if these protrusions 31 and 32 are present, there is no problem in opening the mold.

In particular, according to the above embodiment, the coil lead wire connection terminal 33 is attached to the first protrusion 31 formed on the bobbin 27.
Since the first protrusion 31 also serves as a terminal holder, there is no need to provide a separate terminal holder.

It should be noted that the present invention is not limited to the above-described embodiment; for example, the shapes of the first and second protrusions are both rectangular as shown in FIG. 4 as a different embodiment of the present invention. First and second protrusions 4
1 and 42 may also be used. In this case, each bobbin 2
When the inner flange 29 of 7 attempts to deform into an inner capsule due to the injection pressure of the mold material 38, the first protrusion 41 abuts the opposing second protrusion 42, and the second
The end of the inner flange 29 on the side of the protrusion 42 contacts the first protrusion 41 on the other side, thereby preventing each inner flange 29 from deforming. Further, as shown in FIG. 5 as a further different embodiment of the present invention, the first and second protrusions 43 and 44 may both have a triangular cross section, and even in this case, the same as each of the above embodiments is possible. Similar efficiencies can be obtained.

[Effect of idea]

As is clear from the above description, in the present invention, the inner flange of each bobbin arranged annularly in the stator core has a corresponding inner flange on both ends corresponding to the inner flange of the adjacent bobbin. However, since the structure is such that a protrusion is formed to prevent inward deformation of the bobbin, deformation of the bobbin can be prevented when the stator main body is molded with a molding material, and molding can be carried out reliably. As a result, it is possible to prevent cracks from occurring in the mold material, improving moisture resistance, and furthermore, since it is possible to prevent deformation of the bobbin, it is also possible to prevent deformation of the coil, thereby causing wire breaks and layer shorts in the coil. This has the excellent effect of preventing this from occurring.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention,
Figure 1 is a plan view of the stator body set in the lower mold, Figure 2 shows the stator body being molded with molding material, A-A in Figure 1.
3 is a perspective view of the bobbin, FIG. 4 is a partial plan view of the stator body showing a different embodiment of the present invention, and FIG. 5 is a further different embodiment of the present invention. FIG. 4 is a diagram corresponding to FIG. 4 showing an embodiment. FIG. 6 is a diagram corresponding to FIG. 2 showing a conventional configuration. In the drawing, 21 is a stator main body, 22 is a stator core, 27 is a bobbin, 28 is a body, 29 is an inner flange, 30 is an outer flange, 31 and 32 are first and second protrusions (protrusions), 33 is a terminal for connecting a coil lead wire, 34 and 34a are a coil and its lead wire, 3
8 is a molding material, 41 and 42 are first and second protrusions (protrusions), and 43 and 44 are first and second protrusions (protrusions).

Claims (1)

[Claims for Utility Model Registration] 1. A plurality of bobbins each having a cylindrical body having flanges at both ends and coils wound around the outer periphery of the body are attached to a stator core in an annular arrangement. In a stator main body formed by molding the stator main body with a molding material, on both ends of the inner flange of the two flange portions of each bobbin corresponding to the inner flange of the adjacent bobbin, A stator for an electric motor, characterized in that a protrusion is formed on a corresponding inner flange portion to prevent inward deformation of the inner flange portion. 2. A stator for an electric motor according to claim 1, wherein the protrusion also serves as a terminal holding stand for holding a terminal for connecting a coil lead wire.