JP7615191B2 - Motor device and electric pump - Google Patents

Description

The present invention relates to a motor device and an electric pump.

There is a motor device equipped with a motor (see, for example, Patent Document 1).

JP 2020-010503 A

In the motor device of Patent Document 1, the two cases directly sandwich the stator from the axial direction of the motor. This makes the device larger in the axial direction.

The present invention aims to provide a motor device and an electric pump that are compact in the axial direction.

The above object can be achieved by a motor device comprising a motor, a support member, and a case and cover surrounding the motor, the motor including a rotor and an annular stator arranged radially outward from the rotor, the support member including a cylindrical portion into which the outer peripheral surface of the stator is pressed, and a flange portion extending radially outward from the cylindrical portion, the flange portion being sandwiched between the case and cover, and the thickness of the flange portion in the axial direction of the motor being thinner than the thickness of the stator in the axial direction.

The above object is also to provide an electric pump comprising the above motor device and a blade member that is rotated by the rotor and surrounded by the case and cover.

It is possible to provide a motor device and electric pump that are compact in the axial direction.

FIG. 2 is an external perspective view of the electric pump; FIG. FIG. FIG. FIG. 2 is an external perspective view of a support member. FIG. 5 is a partially enlarged view of FIG. 4 .

[General configuration of electric pump]
Fig. 1 is an external perspective view of the electric pump 1. Figs. 2 and 3 are exploded perspective views of the electric pump 1. The electric pump 1 includes a first case 10, a cover 20, a second case 30, a support member 40, and a rotor 50. The first case 10, the cover 20, the second case 30, and the support member 40 are fixed by a plurality of screws S in an overlapping state in an axial direction A of a motor M described below. The motor M, the first case 10, the cover 20, the second case 30, and the support member 40 are an example of a motor device.

The first case 10 and the second case 30 are made of resin. The cover 20 and the support member 40 are made of metal. The cover 20 is made of, for example, an aluminum alloy. The support member 40 is made of, for example, stainless steel. The first case 10 and the second case 30 overlap in the axial direction A. The support member 40 is sandwiched between the second case 30 and the cover 20. The first case 10 and the second case 30 are examples of a first member and a second member, respectively.

The cover 20 has positioning bosses 28 and 29. The support member 40 has positioning holes 48 and 49. The second case 30 has a positioning recess 38. The positioning boss 28 fits into the positioning hole 48 and the positioning recess 38, thereby defining the positions of the second case 30 and the support member 40 relative to the cover 20. The positioning boss 29 fits into the positioning hole 49, thereby defining the position of the support member 40 relative to the cover 20.

The first case 10 is formed with an inlet pipe section 11 and an outlet pipe section 12. The inlet pipe section 11 draws the fluid into the electric pump 1. The outlet pipe section 12 discharges the fluid from the electric pump 1. In this embodiment, the fluid is a liquid, but it may be a gas. The connector C2 attached to the end of the cable C1 is inserted into the opening 27 of the cover 20. This electrically connects the connector C2 to the printed circuit board P, and power is supplied to the motor M described below.

Figure 4 is a cross-sectional view of the electric pump 1. The motor M is surrounded by the first case 10, the second case 30, and the cover 20. The motor M includes a rotor 50, a stator 64, a coil 66, and a shaft member 82. The rotor 50 includes a holding portion 52, a magnet 62, and a plain bearing 70. The magnet 62 is held at a position radially outside the holding portion 52. The holding portion 52 is made of resin. The magnet 62 is cylindrical. The magnet 62 is magnetized with different polarities in the circumferential direction. The plain bearing 70 is held radially inside the holding portion 52. A blade member 54 is formed at one end of the holding portion 52. The stator 64 is disposed radially outside the magnet 62. A plurality of coils 66 are wound around the stator 64. As will be described in detail later, the stator 64 is supported in a state where it is pressed into the support member 40.

The second case 30 is annular. A partition member 34 is attached to the inside of the second case 30. The partition member 34 is made of metal. The partition member 34 separates the rotor 50 and the stator 64. The fluid introduced from the inlet pipe 11 is introduced into the space defined by the partition member 34 and the first case 10. A rubber O-ring R is disposed between the inner surface of the second case 30 and between the partition member 34 and the first case 10.

The shaft member 82 is inserted into the plain bearing 70. A washer W1 is fitted to one end of the shaft member 82. The washer W1 is sandwiched between the first case 10 and the plain bearing 70. The other end of the shaft member 82 is fixed to the support plate 84 via a washer W2. In this way, the shaft member 82 is fixed so that it cannot rotate. A rubber damper D is disposed between one end of the shaft member 82 and the first case 10. The support plate 84 is disposed at the bottom of the partition member 34.

When the multiple coils 66 are energized, a magnetic force is generated between the stator 64 and the magnets 62. This causes the rotor 50 to rotate. In this manner, the blade members 54 rotate.

[Detailed configuration of support member 40]
Fig. 5 is an external perspective view of the support member 40. Fig. 6 is a partial enlarged view of Fig. 4. The support member 40 is formed by bending a thin metal plate. The support member 40 includes a cylindrical portion 42 and a flange portion 46. The flange portion 46 is located on the blade member 54 side. The cylindrical portion 42 is located on the opposite side to the blade member 54.

The cylindrical portion 42 has a bottomless cylindrical shape. The cylindrical portion 42 includes a press-fit portion 421 and a spaced portion 422. A part of the outer peripheral surface of the stator 64 is press-fitted into the press-fit portion 421. The spaced portion 422 is continuous with the press-fit portion 421. The spaced portion 422 is spaced from the outer peripheral surface of the stator 64. The spaced portion 422 has a larger inner diameter than the press-fit portion 421. The spaced portion 422 faces the stator 64 in a direction B perpendicular to the axial direction A. It is preferable that the length L1 of the press-fit portion 421 in the axial direction A is equal to or greater than one-fourth the length L2 of the stator 64 in the axial direction A. The flange portion 46 extends radially outward from the spaced portion 422.

The flange portion 46 is sandwiched between the cover 20 and the second case 30. Here, the thickness H of the flange portion 46 in the axial direction A is thinner than the length L2 of the stator 64 in the axial direction A. For this reason, the electric pump 1 is made smaller in the axial direction A than when the stator 64 is directly sandwiched between the cover 20 and the second case 30. As described above, the first case 10 and the second case 30 are made of resin, and the cover 20 is made of metal (for example, aluminum alloy). It is also possible to directly connect the stator 64 to them without using the support member 40 by press-fitting or integral molding. However, since the strength and temperature resistance of each material are different, there is a risk of problems occurring in terms of reliability and lifespan. For example, when press-fitting into resin or non-ferrous metal (such as aluminum alloy), the strength of these members is low, and from the viewpoint of idling, cracking, wear, etc., the operating temperature range may be narrower than when press-fitting into steel. In addition, when press-fitting, there is also the problem of increased costs due to the need for processing precision. These problems can also be solved by fastening the stator 64 to the second case 30 and the cover 20 via the support member 40.

The flange portion 46 of the support member 40 overlaps the coil 66 and the stator 64 in a direction B perpendicular to the axial direction A. That is, the flange portion 46, which is sandwiched between the second case 30 and the cover 20, and the press-in portion 421 into which the stator 64 is press-fitted are close to each other. Therefore, the support member 40 can stably support the stator 64.

The size of the support member 40 in the axial direction A is smaller than the size of the coil 66 in the axial direction A. In addition, the cylindrical portion 42 has a bottomless cylindrical shape. In this way, the support member 40 is made smaller. This ensures the rigidity of the support member 40, and also reduces the manufacturing cost of the support member 40.

As described above, part of the outer circumferential surface of the stator 64 is pressed into the press-fit portion 421 of the cylindrical portion 42. Therefore, sliding resistance during press-fitting can be suppressed compared to when the entire outer circumferential surface of the stator 64 is pressed into the press-fit portion 421. In addition, the separation portion 422 is separated from the stator 64. Therefore, workability is improved when pressing the stator 64 into the press-fit portion 421 from the separation portion 422 side.

In the above embodiment, an electric pump 1 equipped with a motor device has been described as an example. The motor device can also be applied to devices other than the electric pump 1, such as an electric fan.

Although the preferred embodiment of the present invention has been described in detail above, the present invention is not limited to the specific embodiment, and modifications and variations are possible within the scope of the gist of the present invention described in the claims.

1 Electric pump 10 First case (case, first member)
20 Cover 30 Second case (case, second member)
40 Support member 42 Cylindrical portion 421 Press-fit portion 422 Spaced portion 46 Flange portion 50 Rotor 54 Blade member 64 Stator 66 Coil M Motor

Claims (9)

A motor;
A support member;
a case and a cover surrounding the motor,
The motor includes a rotor and an annular stator disposed radially outward of the rotor,
the support member includes a cylindrical portion into which an outer circumferential surface of the stator is press-fitted, and a flange portion extending radially outward from the cylindrical portion,
The flange portion is sandwiched between the case and the cover,
a thickness of the flange portion in an axial direction of the motor is smaller than a thickness of the stator in the axial direction;
the cylindrical portion includes a press-fit portion into which a part of an outer circumferential surface of the stator is press-fitted, and a spaced portion spaced from the outer circumferential surface of the stator,
The motor device , wherein the support member is made of metal . The motor includes a coil wound around the stator,
The motor device according to claim 1 , wherein at least a portion of the flange portion overlaps the coil in a direction perpendicular to the axial direction. The motor device of claim 2, wherein the size of the support member in the axial direction is smaller than the size of the coil in the axial direction. The motor device according to claim 3 , wherein the spaced portion faces an outer circumferential surface of the stator in a direction perpendicular to the axial direction. The motor device of claim 4, wherein the cylindrical portion has a bottomless cylindrical shape. 6. The motor device according to claim 1, wherein the case is made of resin. The motor device of claim 1;
a vane member rotated by the rotor and surrounded by the case and cover. the case includes first and second members;
The first member includes an inlet pipe portion for introducing a fluid and a discharge pipe portion for discharging the fluid,
the second member holds a partition member that separates the rotor and the stator;
The electric pump according to claim 7 , wherein the flange portion is sandwiched between the second member and the cover. The flange portion is located on the blade member side,
The electric pump according to claim 7 , wherein the cylindrical portion is located on a side opposite to the impeller member with respect to the flange portion.

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