JP2021083207A - Motor and electrical apparatus having the same - Google Patents

Abstract

To provide a motor with high reliability, capable of ensuring airtightness against invasion of moisture or the like.SOLUTION: A motor 100 includes: a frame 20; a stator 60 and a rotor 50 housed in the frame 20; an end plate 30 covering an opening 21 in the frame 20; and a seal ring 80 made of an annular elastic body. At an outer-peripheral part of an outer face of the end plate 30, there is formed a first step-off 36 with a side face 37 facing an inner-peripheral surface 23 of the frame 20 in the radial direction. At the inner-peripheral surface 23 of the frame 20, there is formed a second step-off 25 facing the first step-off 36 in the radial direction . An annular open space S for housing the seal ring 80 made of an annular elastic body is partitioned by the first step-off 36 and the second step-off 25.SELECTED DRAWING: Figure 4

Description

The present invention relates to a motor and an electric device including the motor, and more particularly to a motor having a structure for preventing the ingress of moisture, oil, etc. from the outside.

In recent years, motors have been widely used for electrical equipment, electric tools, and in-vehicle applications. For example, small motors have been used to drive hydraulic pumps used in antilock braking systems (ABS). Motors used in these applications are required to have higher reliability while being further required to be smaller and lighter. Further, since the motor used for ABS is arranged in the engine room of the vehicle, moisture from the outside may be applied to the motor in rainy weather or the like, and it is necessary to take sufficient waterproof measures.

Therefore, conventionally, in an end plate that is press-fitted into the opening of the frame, which is the outer shell of the motor, to cover this opening, a constant gap is provided between the commutator and the bearing along a rotation shaft rotatably supported by the bearing. A technique for solving the above problems by forming a bearing wall has been proposed (see, for example, Patent Document 1). The end plate is generally made of a resin material in order to electrically insulate the motor from the rotor, the stator, and the like.

Japanese Unexamined Patent Publication No. 2002-204548

By the way, the above-mentioned moisture and the like mainly enter the inside of the frame from the connecting portion between the end plate and the frame. Therefore, a seal ring such as an O-ring or an X-ring is provided at this connecting portion to prevent moisture or the like from entering the frame. On the other hand, when the motor and the load are assembled, a state in which pressure is applied in the axial direction from the load side is assembled to the end plate, and this state is maintained.

However, it is generally known that when the temperature rises while pressure is applied to the resin material, the resin material is deformed by thermal creep. When thermal creep deformation of the end plate occurs, the contact pressure of the seal ring between the end plate, the frame, and the load side decreases, a gap is created between the seal ring and those contact parts, and water is splashed into the gap from the outside. Water may enter the inside of the motor and significantly reduce the reliability and insulation of the motor.

The present invention has been made in view of the above points, and an object of the present invention is to provide a highly reliable motor that maintains the airtightness of a connecting portion between an end plate and a frame, and an electric device using the same.

In order to achieve the above object, the motor according to the present invention includes a bottomed tubular frame having one end opened, a stator housed in the frame, and a stator housed in the frame. An end plate which is a plate-like member which is arranged so as to cover the opening in the opening of the frame and has a through hole in the center through which the rotation shaft is inserted. A first step having a side surface that is radially opposed to the inner peripheral surface of the frame is formed on the outer peripheral portion of the outer surface of the end plate, and the first step is formed on the inner peripheral surface of the frame. A second step facing in the radial direction is formed, and the first step and the second step form an annular open space for accommodating a seal ring made of an annular elastic body. And.

According to this configuration, the load is connected to the rotating shaft of the motor by accommodating the seal ring in the open space composed of the first step provided on the end plate and the second step provided on the frame. If so, this load can be reliably sealed to the inside of the frame. As a result, even when the end plate is deformed due to the influence of heat or pressure, it is possible to prevent moisture or the like from entering the inside of the frame, and a highly reliable motor can be realized.

The electric device according to the present invention is connected to the motor and is driven and connected to the rotating shaft which is connected to the motor and protrudes from the through hole to the outside of the end plate, and is driven according to the rotation of the motor. The seal ring has at least a load having a drive unit, the seal ring has at least the first to third lips, and the cross-sectional shape is X-shaped or Y-shaped, and the seal ring is the load. By being pressed from the surface of the frame toward the bottom of the frame, the first lip is placed at the first corner, which is the corner of the second step, and the second lip is placed on the surface of the load and the inner circumference of the frame. The third corner is in contact with the second corner formed by the surface, and the third lip is in contact with the third corner formed by the surface of the load and the side surface of the first step.

According to this configuration, the seal rings can be brought into contact with the first to third corners, which are the paths through which moisture or the like enters from the outside, and the moisture or the like can enter the inside of the frame or the inside of the load. Can be reliably prevented. As a result, highly reliable electrical equipment can be realized.

As described above, according to the present invention, even when the end plate is deformed due to the influence of heat or pressure, it is possible to prevent moisture or the like from entering the inside of the frame, and it is possible to realize a highly reliable motor.

It is sectional drawing of the main part of the electric apparatus which concerns on Embodiment 1 of this invention. It is a schematic diagram explaining the time-dependent deformation of an end plate and a seal ring for comparison. FIG. 5 is a schematic cross-sectional view of a connecting portion between the end plate and the frame according to the first embodiment. It is an enlarged view of the part surrounded by the broken line of FIG. It is a schematic diagram explaining the time-dependent deformation of the end plate and the seal ring which concerns on Embodiment 1. FIG. It is sectional drawing of the connection part of the end plate and a frame which concerns on Embodiment 2 of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following description of preferred embodiments is merely exemplary and is not intended to limit the present invention, its applications or its uses.

(Embodiment 1)
FIG. 1 shows a schematic cross-sectional view of a main part of an electric device according to the present embodiment.

As shown in FIG. 1, the motor 100 includes a frame 20, an end plate 30, bearings 40 and 41, a rotor 50, a stator 60, a brush 70, and a seal ring 80. Further, the electric device 300 includes a load 200 and a motor 100. In the following description, the longitudinal direction of the rotating shaft 54 forming a part of the rotor 50 is referred to as an axial direction, the radial direction of the end plate 30 is referred to as a radial direction, and the circumferential direction of the end plate 30 is referred to as a circumferential direction. I may call it. Further, in the axial direction, the side of the frame 20 on which the end plate 30 is arranged may be referred to as "upper", and the bottom side of the frame 20 on the opposite side thereof may be referred to as "lower". Further, for convenience of explanation, the details of the load 200 are not shown.

As shown in FIG. 1, the motor 100 includes a frame 20, an end plate 30, bearings 40 and 41, a rotor 50, a stator 60, a brush 70, and a seal ring 80.

The frame 20 is a bottomed semi-cylindrical metal member having a collar around an opening 21 provided at the top. Further, a through hole 22 inserted into one end of the rotating shaft 54 is formed on the bottom surface of the frame 20, and the upper side of the inner peripheral surface 23 of the frame 20 abuts on the inner surface of the end plate 30 to support it. A plurality of plate support portions 24 (see FIGS. 3 to 6) are arranged at intervals in the circumferential direction. Further, in order to press-fit the end plate 30 into the opening 21, an annular flange bent outward in the radial direction is formed at the upper end of the frame 20, that is, in the vicinity of the opening 21.

Further, the inner peripheral surface 23 of the frame 20 is provided with a second step 25 at a position facing the first step 36 described later in the radial direction (see FIGS. 3 and 4). The second step 25 has a bottom surface 26 and a side surface 27, and the bottom surface 26 of the second step 25 has a flat portion. The side surface 27 of the second step 25 corresponds to the inner peripheral surface of the upper end portion of the frame 20 described above.

Further, although not shown, the second step 25 is formed over the entire inner circumference of the frame 20 in the circumferential direction. The second step 25 is formed, for example, by drawing the frame 20. However, the present invention is not particularly limited to this, and it may be formed by another construction method.

The end plate 30 is a plate-shaped member formed by molding a resin material, and has a substantially disk-shaped base portion 31, a through hole 32 provided in the center of the base portion 31, and a brush holding formed on the inner surface of the base portion 31. A portion 33, a bearing holding portion 34 formed on the outer surface of the base portion 31, an electric wire outlet (not shown) from which an electric wire for supplying electric power to the motor 100 from the outside is drawn out, and an outer surface of the base portion 31. It has a first step 36 formed on the outer peripheral portion thereof. Details of the shape of the end plate 30, particularly the shape of the first step 36, will be described later. The first step 36 is formed on the outer peripheral edge of the end plate 30 in the circumferential direction. Further, the electric wire drawn from the electric wire outlet is not shown for convenience of explanation.

Further, as described above, the surface of the end plate 30 facing the inside of the frame 20 is called the "inner surface" of the end plate 30, and the surface of the end plate 30 opposite to the inner surface is the "outer surface" of the end plate 30. May be called.

After positioning the end plate 30 with the frame 20, the end plate 30 is press-fitted into the opening 21 of the frame 20, and the inner surface is brought into contact with the plate support portion 24 provided on the frame 20 to cover the opening 21. The frame 20 is arranged so as to. The rotor 50 is housed in a space partitioned by the frame 20 and the end plate 30. Further, the rotating shaft 54 is inserted through the through hole 22 of the frame 20 and the through hole 32 of the end plate 30 and protrudes outward from the end plate 30, and the bearings 40 provided so as to close the through holes 22 and 32, respectively. It is rotatably supported by 41. Further, a first step 36 is formed on the outer peripheral portion of the outer surface of the end plate 30 (see FIG. 3). The bottom surface 38 of the first step 36 is a flat surface and is formed so as to be orthogonal to the side surface 37 of the first step 36. Note that "orthogonal" means "orthogonal" including the processing tolerance of the first step 36, and does not mean that the two to be compared are strictly orthogonal to each other.

The rotor 50 has an armature core 51, a plurality of salient poles 52, an armature winding 53, a rotating shaft 54, a commutator 55, and an insulator 56. A plurality of salient poles 52 projecting outward in the radial direction are arranged on the armature core 51 at predetermined intervals in the circumferential direction, and an insulator 56 which is an insulating resin is attached to each of the plurality of salient poles 52. The armature winding 53 is wound through the armature winding 53, and the leader wire of the armature winding 53 drawn from the armature core 51 is connected to the commutator 55. The rotating shaft 54 is provided at the axis of the rotor 50, penetrates the center of the armature core 51 and the commutator 55, and is connected to them.

The stator 60 is composed of a frame 20 and a plurality of permanent magnets 61 arranged on the inner peripheral surface 23 of the frame 20 at predetermined intervals in the circumferential direction, and the permanent magnets 61 adjacent to each other in the circumferential direction are configured with each other. They are arranged so that their polarities are different. The frame 20 also functions as a yoke constituting the permanent magnet 61 and the magnetic circuit.

The pair of brushes 70 are composed of a carbon brush material such as graphite containing a solid lubricant, and are held in a brush holding portion 33 provided on the inner surface of the end plate 30, and a brush spring (not shown). ) Is pressed against the commutator 55.

The seal ring 80 is an annular elastic body, for example, EPDM (ethylene / propylene / diene rubber), nitrile rubber, fluororubber, or the like, and is a so-called X ring having an X-shaped cross section. It has lips 80a-80d (see FIG. 4). Further, the seal ring 80 is formed so that the cross-sectional shapes of the first to fourth lips 80a to 80d are the same.

Further, the seal ring 80 is housed in an annular open space S partitioned by the first step 36 and the second step 25 described above, and seals the connecting portion between the frame 20 and the end plate 30. It prevents moisture and the like from entering the inside of the frame 20 from the outside. The annular open space S is an open space whose upper part is open.

The seal ring 80 may be arranged in advance in the motor 100, or when the electric device 300 shown in FIG. 3 is assembled, the seal ring 80 is housed in the annular open space S provided in the motor 100. The load 200 may be connected to the motor 100.

The operation of the motor 100 configured as described above will be described.

Electric power is supplied to the motor 100 from the outside via an electric wire (not shown) drawn from an electric wire outlet provided on the end plate 30. As a result, the armature current flows through the armature winding 53 via the brush 70 and the commutator 55. The magnetic flux generated by the stator 60 and the magnetic field generated by the armature current flowing through the armature winding 53 interact with each other to generate torque, and the rotating shaft 54 is supported by the bearings 40 and 41 to rotate. To do. Further, according to the rotation of the rotating shaft 54, the brush 70 and the commutator 55 periodically repeat contact and separation, and the direction of the armature current flowing through the armature winding 53 is changed corresponding to this cycle. To.

Further, in the electric device 300, the load 200 is arranged on the upper side of the motor 100, and the driven portion 210 is driven and connected to the rotating shaft 54 protruding from the through hole 32 on the outside of the end plate 30. The driven unit 210 includes a mechanical element (not shown) that rotates in the same direction or in the opposite direction according to the rotation of the rotation shaft 54, or converts the rotational motion into a linear motion. The load 200 is, for example, a hydraulic pump. However, it is not limited to this.

Further, the outer shell 220 of the load 200 is assembled to the motor 100 with its surface 221 in contact with the frame 20 and the second and third lips 80b and 80c of the seal ring 80. The motor 100 and the load 200 are arranged so that the surface 221 of the outer shell 220 and the outer surface of the end plate 30 are separated from each other while maintaining a predetermined clearance. The outer shell 220 is, for example, a block made of aluminum. However, it is not limited to this. Further, in the following description, the surface 221 of the outer shell 220 may be referred to as the surface 221 of the load 200.

When pressed from the surface 221 of the load 200 to the lower side, that is, to the bottom side of the frame 20, the seal ring 80 is compressed and deformed, and the four lips 80a to 80d are formed into an annular open space S and the surface of the load 200. It is in contact with four corners C1 to C4 (see FIGS. 2 to 4) of the space partitioned by 221.

The first lip 80a abuts on the first corner portion C1 corresponding to the corner portion of the second step 25 formed on the frame 20, and the second lip 80b is the inner peripheral surface 23 of the frame 20 and the surface 221 of the load 200. It is in contact with the second corner portion C2 composed of. In the second corner portion C2, the second lip 80b may not sufficiently contact the inner peripheral surface 23 of the frame 20, and may mainly contact only the surface 221 of the load 200. .. Further, the third lip 80c abuts on the third corner portion C3 composed of the surface 221 of the load 200 and the side surface 37 of the first step 36, and the fourth lip 80d corresponds to the corner portion of the first step 36. It is in contact with the fourth corner portion C4. The first lip 80a is located diagonally to the third lip 80c in cross-sectional view, and the second lip 80d is located diagonally to the fourth lip 80d in cross-sectional view.

In this way, the seal ring 80 and the load 200, the frame 20 and the end plate 30 are in contact with each other, and pressure is applied to the contact surface portion, so that between the frame 20 and the end plate 30 and between the frame 20 and the load 200. Is sealed, and it is possible to prevent moisture from the outside from entering the inside of the frame 20 from the load 200 side. Further, by sealing between the end plate 30 and the load 200, it is possible to prevent moisture and the like from adhering to the bearing 41 and the rotating shaft 54.

[Findings leading to the invention of the present application]
FIG. 2 shows a schematic diagram illustrating the time-dependent deformation of the end plate and the seal ring for comparison. For convenience of explanation, in the motor 100, components other than the frame 20, the end plate 30, the seal ring 80, and the bearing 41 are not shown. Further, in the load 200, only a part of the outer shell 220 including the surface 221 is shown.

In FIG. 2, the annular open space S is composed of a first step 36 and an inner peripheral surface 23 of the frame 20.

The upper view of FIG. 2 shows a state immediately after the motor 100 and the load 200 are assembled. In this state, the members maintain the arrangement relationship as designed within the range of the assembly tolerance. However, in this state, pressure is applied from the load 200 side to the motor 100 side. For example, in the case shown in FIG. 2, the pressure is applied to the central portion of the end plate 30 via the bearing 41 housed in the bearing holding portion 34. Has been added. Even when the bearing 41 is arranged inside the frame 20, pressure is applied from the load 200 side to the central portion of the end plate 30.

On the other hand, when the electric device 300 is started to be used, the temperature of the motor 100 and the load 200 starts to rise due to the driving of the motor 100, the operation of the load 200, the temperature of the environment in which the electric device 300 is arranged, and the like. .. As described above, when the temperature rises while pressure is applied to the resin material, the resin material is deformed by thermal creep, so that the center side of the end plate 30 molded using the resin material is pushed downward. In addition, the outer peripheral side is deformed so as to be lifted upward accordingly.

As a result, as shown on the lower side of FIG. 2, in the annular open space S, the space between the side surface 37 of the first step 36 and the inner peripheral surface 23 of the frame 20 is opened, and in particular, the first corner portion C1 In, the contact pressure at which the first lip 80a of the seal ring 80 presses the inner peripheral surface 23 of the frame 20 becomes low. As a result, the inventors of the present application have found that the sealing property of the seal ring 80 at the first corner portion C1 is lowered, and a fluid such as moisture easily enters the inside of the frame 20.

Therefore, the inventors of the present application have focused on the first corner portion C1 which is a direct path for the fluid to enter the inside of the frame 20, and formed an annular open space S in the end plate 30 for accommodating the seal ring 80. It has been found that the airtightness in the vicinity of the first corner portion C1 can be maintained by forming the first step 36 and the second step 25 formed on the frame 20.

[Structure of the connecting part between the end plate and the frame]
FIG. 3 is a schematic cross-sectional view of a connecting portion between the end plate and the frame according to the present embodiment, FIG. 4 is an enlarged view of the portion surrounded by the broken line in FIG. 3, and FIG. 5 is the present embodiment. Schematic diagrams illustrating the time-dependent deformation of the end plate and the seal ring are shown. Note that FIG. 3A shows a state in which the seal ring 80 is not housed in the annular open space S, and FIG. 3B shows a state in which the seal ring 80 is housed. Further, FIG. 4 shows an enlarged view of a portion surrounded by a broken line in FIG. 3 (b).

In the end plate 30 shown in FIG. 2, an annular open space S is formed by the first step 36 and the inner peripheral surface 23 of the frame 20, whereas in the configuration of the present embodiment shown in FIGS. 3 to 5, the first step 36 and the inner peripheral surface 23 of the frame 20 form an annular open space S. As described above, the first step 36 and the second step 25 form an annular open space S.

As shown in FIG. 4, the height H of the second step 25 in the axial direction is lower than the height H1 in the axial direction of the seal ring 80, specifically, H ≦ 0.5H1. It is formed so as to be. Further, the radial width W of the bottom surface 26 of the second step 25 is formed to be wider than the radial width W1 of the seal ring 80.

When the load 200 is assembled to the motor 100 on which the seal ring 80 is arranged in this way, the surface 221 of the load 200 becomes the second and third lips 80b of the seal ring 80, as shown on the upper side of FIG. Each of them comes into contact with the 80c and presses the seal ring 80 downward. Further, as shown on the lower side of FIG. 5, the load 200 further lowers the central portion of the end plate 30 via the bearing 41 housed in the bearing holding portion 34 by thermal creep. Therefore, in the seal ring 80, the first to fourth lips 80a to 80d come into contact with the first to fourth corner portions C1 to C4, respectively, and the connecting portion between the frame 20 and the end plate 30 and the load on the frame 20. It is compressed and deformed so as to seal the connecting portion and the like with the surface 221 of the 200.

In the present embodiment, since the first lip 80a is in contact with the first corner portion C1 which is the corner portion of the second step 25 provided on the frame 20, the outer peripheral side of the end plate 30 is lifted upward by thermal creep. Even if it is deformed in this way, the contact pressure of the seal ring 80 at the first corner portion C1 does not decrease. Further, the contact surface pressure of the seal ring 80 at the fourth corner portion C4 is not so affected by the deformation of the end plate 30. By doing so, it is possible to prevent moisture or the like from entering the inside of the frame 20 from the boundary portion between the end plate 30 and the frame 20 located between the first corner portion C1 and the fourth corner portion C4. Can be done.

The first corner portion C1 is a corner portion having a predetermined radius of curvature. By doing so, when an impact is applied to the motor 100, particularly the frame 20, the embezzlement concentration in the first corner portion C1 is alleviated, and the strength of the frame 20 can be maintained high.

[Effects, etc.]
As described above, the motor 100 according to the present embodiment has a bottomed tubular frame 20 having one end opened, a stator 60 housed in the frame 20, and a stator housed in the frame 20. A rotor 50 arranged at a predetermined interval from the 60, and an end plate 30 which is a resin plate-like member arranged so as to cover the opening 21 in the opening 21 of the frame 20 are provided. There is. A through hole 32 through which the rotating shaft 54 is inserted is provided in the center of the end plate 30.

Further, a first step 36 having a side surface 37 that faces the inner peripheral surface 23 of the frame 20 in the radial direction is formed on the outer peripheral portion of the outer surface of the end plate 30.

A second step 25 facing the first step 36 in the radial direction is formed on the inner peripheral surface 23 of the frame 20.

An annular open space S for accommodating the seal ring 80 made of an annular elastic body is formed by the first step 36 and the second step 25.

By configuring the motor 100 in this way, the seal ring 80 is housed in the annular open space S, and when a pressing force from above to downward is applied to the seal ring 80, the seal ring at the first corner portion C1. It is possible to suppress a decrease in the contact pressure of 80. As a result, the airtightness inside the motor 100 can be maintained, moisture and the like can be prevented from entering the inside of the frame 20, and the motor 100 with high reliability can be realized.

Further, the second step 25 is formed so that its axial height H is lower than the axial height H1 of the seal ring 80. By doing so, as shown in FIG. 4, when the load 200 is attached to the motor 100, the seal ring 80 is compressed and deformed and accommodated inside the annular open space S. At this time, a restoring force that tries to return to the original shape is generated in the first to fourth lips 80a to 80d. Due to this restoring force, the first to fourth lips 80a to 80d abutting on the first to fourth corner portions C1 to C4 press the first to fourth corner portions C1 to C4, respectively, and the frame 20 and the end The connecting portion with the plate 30 and the connecting portion between the frame 20 and the surface 221 of the load 200 are sealed.

It is preferable that the height H of the second step 25 in the axial direction is lower than the height H1 in the axial direction of the seal ring 80. Specifically, it is more preferable that H ≦ 0.5 H1. By doing so, the airtightness of the connecting portion with the end plate 30 and the connecting portion between the frame 20 and the surface 221 of the load 200 is further improved.

Further, the bottom surface 26 of the second step 25 has a flat portion. By doing so, the first lip 80a is securely installed on the bottom surface 26 of the second step 25. Therefore, the contact pressure of the seal ring 80 at the first corner portion C1 is maintained, and the connecting portion between the frame 20 and the end plate 30 is reliably sealed.

It is preferable that the width W of the bottom surface 26 of the second step 25 is wider than the radial width W1 of the seal ring 80. By doing so, the first lip 80a is surely installed on the bottom surface 26 of the second step 25, and the connecting portion between the frame 20 and the end plate 30 is surely sealed.

Further, by forming the cross section of the seal ring 80 into an X shape, the seal ring 80 is provided at two locations with respect to the bottom surface 38 of the first step 36 and the bottom surface 26 of the second step 25, which are the installation surfaces of the seal ring 80. In this case, since the first lip 80a and the fourth lip 80d come into contact with each other, the position of the seal ring 80 in the annular open space S can be stabilized.

Further, by forming the cross section of the seal ring 80 into an X shape, it is possible to reduce the twist when the seal ring 80 is housed in the annular open space S, and the contact surface pressure is dispersed over the entire cross section of the seal ring 80. Therefore, there is little leakage and good airtightness can be obtained. Further, since the burrs generated when the X-shaped seal ring 80 is formed are usually not on the contact surface, that is, in the recesses between the adjacent lips, good airtightness can be obtained.

Of the four corner portions C1 to C4 shown in FIGS. 3 to 5, the second corner portion C2 is most likely to allow moisture or the like to enter from the outside, but in order to ensure the reliability of the motor 100, The most necessary to maintain airtightness is the boundary portion between the end plate 30 and the frame 20 located between the first corner portion C1 and the fourth corner portion C4. Further, if moisture or the like enters from the third corner portion C3, the damage to the bearing 41 and the rotating shaft 54 becomes large, and the performance of the motor 100 and eventually the electric device 300 may be deteriorated.

As shown in the present embodiment, by making the seal ring 80 an elastic body having an X-shaped cross section, the first to fourth lips 80a to 80d of the seal ring are formed on the first to fourth corner portions C1 to C4. Can be brought into contact with each other, and sufficient airtightness with respect to the entry path of moisture or the like from the outside can be ensured.

The electric device 300 according to the present embodiment is connected to the motor 100 and the motor 100, and is driven and connected to the rotating shaft 54 protruding from the through hole 32 to the outside of the end plate 30, and is driven according to the rotation of the motor 100. It includes at least a load 200 having a driven portion 210 to be driven.

The seal ring 80 is pressed from the surface 221 of the load 200 toward the bottom of the frame 20, so that the first lip 80a loads the first corner portion C1 which is the corner of the second step 25, and the second lip 80b loads. At the second corner portion C2 composed of the surface 221 of the 200 and the inner peripheral surface 23 of the frame 20, the third lip 80c is the third corner composed of the surface 221 of the load 200 and the side surface 37 of the first step 36. The fourth lip is in contact with the portion C3 at the fourth corner portion C4, which is the corner portion of the first step 36.

By configuring the electric device 300 in this way, the end plate is caused by the heat continuously generated when the motor 100 is driven and the driven portion 210 of the load 200 is operated and the pressure applied to the end plate 30. Even when the 30 is deformed, it is possible to prevent moisture and the like from entering the inside of the frame 20 and the inside of the load 200, and it is possible to realize a highly reliable electric device 300. Further, the contact pressures of the first to fourth lips 80a to 80c are increased with respect to the first to fourth corner portions C1 to C4, respectively, so that moisture and the like can enter the inside of the frame 20 and the inside of the load 200. It can be reliably prevented.

Further, the electric device 300 of the present embodiment is useful because it is arranged in an external environment and can ensure high reliability when it is continuously used in a state where the environmental temperature reaches several tens of degrees or more.

(Embodiment 2)
FIG. 6 shows a schematic cross-sectional view of a connecting portion between the end plate and the frame according to the present embodiment.

In the configuration of the first embodiment shown in FIGS. 3 and 4, the cross section of the seal ring 80 is X-shaped, whereas in the configuration of the present embodiment shown in FIG. 6, the cross section of the seal ring 81 is Y-shaped or It differs in that it has a deformed T-shape.

Of the four corner portions C1 to C4 shown in FIGS. 3 to 5, the fourth corner portion C4 is composed of the side surface 37 and the bottom surface 38 of the first step 36 integrally molded with resin, and the frame 20 is formed from this portion. The risk of moisture entering the inside is much smaller than in other corners. Therefore, as shown in FIG. 6, using the seal ring 81 having the first to third lips 81a to 81c, the first to third lips 81a to 81c are applied to the first to third corner portions C1 to C3, respectively. You may make them touch. Also in this case, similarly to the configuration shown in the first embodiment, the airtightness of the motor 100 can be maintained to prevent moisture and the like from entering the inside of the frame 20, and the highly reliable motor 100 and electricity can be prevented. The device 300 can be realized.

Further, also in the case of the present embodiment, the twisting of the seal ring 81 during accommodation can be reduced, and the contact surface pressure is dispersed over the entire cross section of the seal ring 81, so that leakage is small and good sealing performance can be obtained. It goes without saying that good airtightness can be obtained because the burrs generated during molding are other than the contact surface, that is, in the recesses between the adjacent tip portions.

(Other embodiments)
In the first embodiment, the case where the motor 100 is a brushed motor has been illustrated, but the present invention is not particularly limited to this, and for example, a brushless motor or another type of motor may be used. Further, the motor 100 in the present embodiment describes a case where the stator 60 is arranged on the radial outer side of the rotor 50, that is, a so-called inner rotor type motor, but another type of motor, for example, Needless to say, it can also be applied to a so-called outer rotor type motor in which rotors 50 are arranged at predetermined intervals on the radial outer side of the stator 60.

Further, the bearing 41 arranged on the through hole 32 side of the end plate 30 is housed in the bearing holding portion 34 and is in contact with the outer surface of the end plate 30, but is arranged on the inner surface side of the end plate 30. It may be housed inside the frame 20.

Further, although the brush 70 is accommodated in the brush holding portion 33 provided integrally with the end plate 30, the brush holding portion 33 is provided inside the frame 20 separately from the end plate 30 to accommodate the brush 70. You may do so.

Further, the cross-sectional shapes of the first to fourth lips 80a to 80d provided on the seal ring 80 do not necessarily have to be the same. For example, the shape of two or more lips may be the same, or the shape of each lip may be different. This also applies to the first to third lips 81a to 81c provided on the seal ring 81.

Further, although the stator 60 is composed of a frame 20 and a plurality of permanent magnets 61, the stator 60 is fielded in another structure, for example, a plurality of field magnetic poles arranged at predetermined intervals in the circumferential direction. A magnetic winding may be wound to form the stator 60.

Since the motor according to the present invention can prevent the ingress of moisture, oil, etc. from the outside, it is useful for application to electric equipment including a fluid pump such as a hydraulic pump and electric equipment arranged in a high temperature external environment. is there.

20 Frame 21 Opening 22, 32 Through hole 23 Inner peripheral surface 24 Plate support part 25 Second step 26 Bottom of second step 27 Side of second step 30 End plate 31 Base 33 Brush holding part 34 Bearing holding part 36 First step 37 Side surface of the first step 38 Bottom surface of the first step 40,41 Bearing
50 Rotor 51 Armature core 52 Slip pole 53 Armature winding 54 Rotor shaft 55 Commutator 56 Insulator 60 Stator 61 Permanent magnet 70 Brush 80 Seal ring 80a-80d 1st to 4th lip 81 Seal ring 81a-81c 1st to 3rd lip 100 Motor 200 Load 210 Driven part 220 Outer 221 Surface of load 200 (surface of outer 220)
300 Electrical equipment C1 to C4 1st to 4th corners S Circular open space

Claims (8)

A bottomed tubular frame with one end open,
The stator housed in the frame and
A rotor housed in the frame and arranged at a predetermined distance from the stator,
An end plate, which is a plate-like member arranged in the opening of the frame so as to cover the opening and having a through hole through which a rotation shaft is inserted, is provided at least.
A first step having a side surface that faces the inner peripheral surface of the frame in the radial direction is formed on the outer peripheral portion of the outer surface of the end plate.
A second step that is radially opposed to the first step is formed on the inner peripheral surface of the frame.
A motor characterized in that an annular open space for accommodating a seal ring made of an annular elastic body is partitioned between the first step and the second step. In the motor according to claim 1,
A motor characterized in that the bottom surface of the second step has a flat portion. In the motor according to claim 1 or 2.
A motor characterized in that the height of the second step in the axial direction is lower than the height of the seal ring in the axial direction. In the motor according to claim 3,
A motor characterized in that the height of the second step in the axial direction is less than half the height of the seal ring in the axial direction. In the motor according to any one of claims 1 to 4.
The motor having at least the first to third lips and having a cross-sectional shape of an X-shape or a Y-shape. In the motor according to claim 5,
A motor characterized in that the radial width of the bottom surface of the second step is wider than the width of the first lip. The motor according to claim 5 or 6,
At least a load having a driven portion connected to the motor, driven to the rotating shaft protruding from the through hole to the outside of the end plate, and driven in response to the rotation of the motor, is provided.
When the seal ring is pressed from the surface of the load toward the bottom of the frame, the first lip is placed on the first corner portion which is the corner of the second step, and the second lip is placed on the load. The third lip is in contact with the second corner formed by the surface and the inner peripheral surface of the frame, and the third lip is in contact with the third corner formed by the surface of the load and the side surface of the first step. An electrical device that is characterized by that. In the electrical device according to claim 7,
The seal ring further has a fourth lip and has an X-shaped cross section.
An electric device characterized in that the fourth lip is in contact with a fourth corner portion, which is a corner portion of the first step.

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