CN115459518A

CN115459518A - Motor with brake, driving device and wheel driving device

Info

Publication number: CN115459518A
Application number: CN202211228568.XA
Authority: CN
Inventors: 冈村晖久夫; 井上仁
Original assignee: Nidec Shimpo Corp
Current assignee: Nidec Drive Technology Corp
Priority date: 2019-02-15
Filing date: 2020-02-14
Publication date: 2022-12-09
Also published as: CN111585386B; CN111585386A; JP2020137211A; JP7235227B2

Abstract

The invention provides a motor with a brake, a driving device and a wheel driving device. The outer peripheral surface of the stator is fixed to the radially inner side of the cylindrical portion, and the stator has a through hole in the axial center portion. The rotor is relatively rotatably provided on the radial inner side of the cylinder portion. The rotating shaft is inserted into the through hole of the stator. The pair of disks are provided on both sides of the stator in the axial direction, and are coupled to each other so as to be incapable of relative rotation with respect to the rotating shaft and slidable in the axial direction. The magnets are fixed to the end surface of the disk, which faces the stator, among the two end surfaces in the axial direction. The pressing member is disposed radially outward of the rotating shaft and inserted into the through hole of the stator. The pair of friction plates are located between the circular plate disposed on one axial side of the stator and the 1 st cover portion and between the circular plate disposed on the other axial side of the stator and the 2 nd cover portion.

Description

Brake-equipped motor, drive device, and wheel drive device

The present application is a divisional application of the chinese invention patent application having an application number of 202010092332.2, an application date of 2020, 2/14, entitled "brake-equipped motor, drive device, and wheel drive device".

Technical Field

The present invention relates to a motor with a brake, a driving device with a brake, and a wheel driving device with a brake.

Background

Conventionally, a motor having a brake mechanism is known. Such a motor is disclosed in, for example, japanese patent laid-open publication No. 2015-39276. In the motor disclosed in japanese patent application laid-open No. 2015-39276, the rotor 10 is axially supported between a position where the housing member 13 abuts against a part of the base surface 10a and a position where the friction member 30 contacts the disc surface 10 b. In a state where the coil 25 is not energized, the biasing member 16 biases the base surface 10a of the rotor 10 upward so that the disk surface 10b contacts the friction member 30. Thus, when the coil 25 is not energized, the rotor 10 is pressed against the friction member 30 by the biasing member 16, and the brake is applied.

On the other hand, in the motor disclosed in japanese patent application laid-open No. 2015-39276, the rotor 10 is attracted by the stator 20 by a magnetic attraction force generated in the stator 20 by energization of the coil 25, and the contact between the disk surface 10b and the friction member 30 is released.

According to the motor disclosed in japanese patent laid-open No. 2015-39276, rotation/stop of the motor and on/off of the brake can be simultaneously achieved.

Disclosure of Invention

However, in the motor disclosed in japanese patent laid-open No. 2015-39276, the contact area between the disk surface 10b and the friction member 30 may not be sufficient, resulting in insufficient braking force. Further, in the motor disclosed in japanese patent application laid-open No. 2015-39276, since the reaction force of the biasing member 16 continues to act on the bearing portion, the rotational resistance of the bearing portion lowers the motor efficiency, and improvement thereof is desired. Further, a motor capable of rotating the rotor 10 more strongly is desired.

The invention aims to provide a motor with a brake, a driving device with the brake and a wheel driving device with the brake, which are small in size, can strongly output rotation and can exert excellent braking force.

The problems to be solved by the present invention are as described above, and a method for solving the problems will be described below.

According to an exemplary embodiment of the present invention, there is provided a motor with a brake including a housing, a stator, a rotor, and a pair of friction plates. The housing has: a cylindrical portion extending in an axial direction; a 1 st cover part for closing one side of the cylinder part in the axial direction; and a 2 nd lid portion that closes the other side in the axial direction of the cylindrical portion. The stator is annular, has an outer peripheral surface fixed to a radially inner side of the cylindrical portion of the housing, and has a through hole penetrating in an axial direction in an axial center portion. The rotor is disposed radially inward of the cylindrical portion of the housing and is provided so as to be relatively rotatable with respect to the stator. The rotor includes a rotating shaft, a pair of disks, a magnet, and a pressing member. The rotating shaft extends in the axial direction and is inserted into the through hole of the stator. The pair of disks are provided on both sides of the stator in the axial direction with the stator interposed therebetween, and are coupled to each other so as to be incapable of relative rotation with respect to the rotating shaft and slidable in the axial direction. The magnets are fixed to the end surface of the disk, which faces the stator, among the two end surfaces in the axial direction. The pressing member is disposed radially outward of the rotating shaft, is inserted into the through hole of the stator, and presses the pair of disks in a direction separating from each other. The pair of friction plates are located between the circular plate and the 1 st cover portion that are disposed on one side in the axial direction of the stator, and between the circular plate and the 2 nd cover portion that are disposed on the other side in the axial direction of the stator. The brake-equipped motor further includes a bush disposed radially outward of the pressing member and radially inward of the magnet, the bush being axially sandwiched between the pair of disks, the bush having a through hole in an axial center portion thereof, the bush including: a small diameter portion disposed inside the through hole of the stator; and a large diameter portion provided on both sides of the small diameter portion in an axial direction with the small diameter portion interposed therebetween, the large diameter portion being in contact with the circular plate when the stator is energized.

A drive device with a brake includes a housing, a partition, a motor, and a planetary reduction mechanism. The housing has a cylindrical portion extending in the axial direction and a lid portion closing one axial side of the cylindrical portion. The partition section partitions a space on the inside in the radial direction of the cylindrical section of the housing into a 1 st space on one axial side and a 2 nd space on the other axial side. The motor is disposed in the 1 st space. The planetary reduction mechanism is disposed in the 2 nd space. The planetary reduction mechanism has a rigid ring, a rotating body, and an input member. A rigid ring having an inner contact portion on an inner circumferential portion and having an annular shape is fixed to an inner circumferential surface of the housing so as not to be relatively rotatable. The rotating body is disposed radially inward of the rigid ring, has an outer contact portion that contacts the inner contact portion, and has a mounting portion to which the output member can be mounted. The input member is disposed radially inward of the rolling element, and changes the contact position between the inner contact portion and the outer contact portion in the circumferential direction by rotating. The motor includes a stator, a rotor, and a pair of friction plates. The outer peripheral surface of the stator is fixed to the radially inner side of the cylindrical portion of the housing, and the stator has an annular through hole penetrating in the axial direction in the axial center portion. The rotor is provided so as to be relatively rotatable with respect to the stator. The rotor has a rotating shaft, a pair of disks, a magnet, and a pressing member. The rotating shaft is inserted into the through hole of the stator. The pair of disks are provided on both sides of the stator in the axial direction with the stator interposed therebetween, and are coupled to each other so as to be incapable of relative rotation with respect to the rotating shaft and slidable in the axial direction. The magnets are fixed to the end surface of the disk, which faces the stator, among the two end surfaces in the axial direction. The pressing member is disposed radially outward of the rotating shaft, is inserted into the through hole of the stator, and presses the pair of disks in a direction separating from each other. The pair of friction plates are located between the disk and the cover portion arranged on one side in the axial direction of the stator and between the disk and the partition portion arranged on the other side in the axial direction of the stator. The input member and the rotary shaft are coupled in a relatively non-rotatable manner. The rotor further includes a bush disposed radially outside the pressing member and radially inside the magnet, the bush being sandwiched by the pair of disks in an axial direction, the bush having a through hole in a shaft center portion, the bush including: a small diameter portion disposed inside the through hole of the stator; and a large diameter portion provided on both sides of the small diameter portion in an axial direction with the small diameter portion interposed therebetween, the large diameter portion being in contact with the circular plate when the stator is energized.

The wheel drive device with a brake includes the drive device with a brake and a hub. The hub has a flange portion and a wheel mounting portion. The flange portion is annular and attachable to the other end surface of the output member in the axial direction. The wheel mounting portion extends in a cylindrical shape from the outer edge of the flange portion toward one side in the axial direction, covers a part or the whole of the housing, and is capable of mounting a wheel on the radial outer side.

According to an exemplary embodiment of the present invention, a brake-equipped motor, a brake-equipped drive device, and a brake-equipped wheel drive device that are small in size, capable of strongly outputting rotation, and capable of exhibiting excellent braking force are provided.

The above and other features, elements, steps, features and advantages of the present invention will be more clearly understood from the following detailed description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings.

Drawings

Fig. 1 is a longitudinal sectional view of a motor with a brake according to embodiment 1 when power is applied.

Fig. 2 is a schematic view of the rotating shaft and the circular plate according to embodiment 1 when viewed in the axial direction.

Fig. 3 is a longitudinal sectional view of the brake-equipped motor according to embodiment 1 when the current is cut off.

Fig. 4 is a longitudinal sectional view of the motor with a brake according to embodiment 2.

Fig. 5 is a longitudinal sectional view of the motor with a brake according to embodiment 3.

Fig. 6 is a longitudinal sectional view of the brake-equipped drive device according to embodiment 4.

Fig. 7 is a schematic view of the rotary shaft, the disk, and the shaft according to embodiment 4 when viewed in the axial direction.

Fig. 8 is a schematic view of the planetary reduction mechanism provided in the brake-equipped drive device according to embodiment 4 when viewed in the axial direction.

Fig. 9 is a longitudinal sectional view of the brake-equipped drive device according to embodiment 5.

Fig. 10 is a longitudinal sectional view of the brake-equipped drive device according to embodiment 6.

Fig. 11 is a longitudinal sectional view of the brake-equipped drive device according to embodiment 7.

Fig. 12 is a schematic view of the planetary reduction mechanism provided in the brake-equipped drive device according to embodiment 7, as viewed in the axial direction.

Fig. 13 is a longitudinal sectional view of the brake-equipped drive device according to embodiment 8.

Fig. 14 is a schematic view of the planetary reduction mechanism provided in the brake-equipped drive device according to embodiment 8, as viewed in the axial direction.

Fig. 15 is a longitudinal sectional view of the wheel drive device with a brake according to embodiment 9.

Fig. 16 is a schematic view of the rotary shaft, the disk, and the input member according to embodiment 9 as viewed in the axial direction.

Fig. 17 is a schematic view of a planetary reduction gear mechanism provided in the braked wheel drive apparatus according to embodiment 9, as viewed in the axial direction.

Fig. 18 is a longitudinal sectional view of the wheel drive device with a brake according to embodiment 10.

Fig. 19 is a schematic view of a planetary reduction mechanism provided in the wheel drive device with a brake according to embodiment 10, as viewed in the axial direction.

Detailed Description

Hereinafter, exemplary embodiments of the present application will be described with reference to the drawings. In the present application, a direction parallel to the center axis of the brake-equipped motor is referred to as an "axial direction", a direction perpendicular to the center axis of the brake-equipped motor is referred to as a "radial direction", and a direction along an arc centered on the center axis of the brake-equipped motor is referred to as a "circumferential direction". In the present application, the "parallel direction" also includes a substantially parallel direction. In the present application, the term "vertical direction" also includes a substantially vertical direction.

<1. Embodiment 1 >

<1-1. Integral Structure of Motor with brake >

The overall structure of the motor 100 with a brake according to embodiment 1 will be described below with reference to fig. 1 to 3. Fig. 1 is a longitudinal sectional view of a motor 100 with a brake when energized. Fig. 2 is a schematic view of a part of the motor 100 with a brake according to embodiment 1 when viewed in an axial direction. Fig. 3 is a longitudinal sectional view of the brake-equipped motor 100 when the current is cut off.

The brake-equipped motor 100 according to the present embodiment is a device that rotates a rotating body with respect to a fixed body by the action of magnetic flux between the fixed body and the rotating body and outputs the rotation. As described later, the brake-equipped motor 100 includes a brake mechanism that stops the rotation of the rotating body with respect to the fixed body. The motor 100 with a brake includes a housing 10, a stator 20 as a fixed body, a rotor 30 as a rotating body, a bush 40, and a pair of friction plates 50.

<1-2. Structure of housing >

The housing 10 is a case that accommodates other components constituting the motor 100 with a brake therein. The housing 10 has a cylindrical portion 11, a 1 st lid portion 13, and a 2 nd lid portion 14.

The cylindrical portion 11 is a cylindrical portion extending in the axial direction. The cylindrical portion 11 of the present embodiment is divided into two parts on one axial side and the other axial side. The two portions are fixed to each other by a fastening member 12 such as a bolt.

The 1 st lid portion 13 is a disk-shaped portion extending radially inward from one end portion in the axial direction of the cylindrical portion 11. The 1 st cover portion 13 covers components housed in the housing 10 from one side in the axial direction. That is, the 1 st lid 13 closes one side of the cylinder 11 in the axial direction.

The 2 nd lid portion 14 is a substantially disk-shaped portion extending radially inward from the other end portion in the axial direction of the cylindrical portion 11. The 2 nd lid portion 14 closes the other side in the axial direction of the barrel portion 11. However, the 2 nd lid portion 14 has a through hole 16 penetrating in the axial direction in the axial center portion. A rotation shaft 31 described later is inserted into the through hole 16.

<1-3. Structure of stator >

The stator 20 includes a laminated steel plate portion 21 and a base portion 22. The laminated steel plate portion 21 is a laminated structure in which a plurality of annular magnetic bodies centered on the central axis C are laminated, and the axial center portion of the laminated steel plate portion 21 is hollow. The base portion 22 is a substantially annular portion. The outer peripheral surface of the base portion 22 is fixed to the inner peripheral surface of the laminated steel plate portion 21. Although not shown in fig. 1, the stator 20 has a plurality of coils. Each coil is provided in the stator 20 with its core parallel to the central axis C. The base part 22 of the stator 20 has a through hole 23 penetrating in the axial direction in the axial center part. The inner peripheral surface of the through-hole 23 is circular when viewed in the axial direction.

The stator 20 is fixed to the radially inner side of the cylindrical portion 11 of the housing 10. More specifically, in the present embodiment, the outer peripheral surface of the laminated steel plate portion 21 is fixed to the inner peripheral surface of the tube portion 11 with an adhesive, for example. However, the method of fixing the stator 20 to the cylindrical portion 11 is not limited to this. For example, instead of or in addition to the above, the outer peripheral portion of the laminated steel plate portion 21 may be press-fitted into the inner peripheral surface of the tube portion 11. In this case, the groove bottom of the groove portion 15 provided on the inner circumferential surface of the cylindrical portion 11 does not have to be in contact with the outer circumferential surface of the laminated steel plate portion 21.

<1-4. Structure of rotor >

The rotor 30 is disposed coaxially with the stator 20, and the rotor 30 is provided so as to be rotatable relative to the stator 20. The rotor 30 is disposed radially inward of the cylindrical portion 11. Specifically, the rotor 30 includes a rotating shaft 31, a pair of

disks

32 and 32, a pair of

magnets

33 and 33, and a pressing member 34.

The rotary shaft 31 is a substantially columnar member extending in the axial direction. The rotary shaft 31 is inserted into the through hole 23 of the base portion 22 of the stator 20 and the through hole 16 of the 2 nd cover portion 14. As shown in fig. 1 and 2, the rotary shaft 31 has a spline 31s on an outer peripheral surface of a part in the axial direction. The spline 31s has a plurality of recesses and projections arranged in the circumferential direction. The plurality of concave portions and the plurality of convex portions extend in the axial direction.

As shown in fig. 1, the pair of

disks

32 and 32 is provided on both sides of the stator 20 in the axial direction with the stator 20 interposed therebetween. As shown in fig. 2, each disk 32 has a substantially annular shape when viewed in the axial direction. The disks 32 are coupled to each other so as to be relatively non-rotatable with respect to the rotary shaft 31 and slidable in the axial direction. Specifically, each disk 32 has a spline 32s on the inner peripheral portion. The spline 32s has a plurality of recesses and protrusions arranged in the circumferential direction. The plurality of concave portions and the plurality of convex portions extend in the axial direction. The spline 32s of each disk 32 engages with the spline 31s of the rotary shaft 31. As shown in fig. 1, the pair of circular plates 32 has a shape that is line-symmetrical with respect to a virtual straight line extending in the radial direction of the stator 20 with the stator 20 interposed therebetween.

The magnets 33 are fixed to the end surface of each disk 32 facing the stator 20, out of the two end surfaces in the axial direction. Specifically, the magnet 33 is disposed on the end surface of the disk 32 on the side facing the paired disks 32, at a position radially outward of the rotation shaft 31. The magnet 33 is fixed to the entire circumference in the circumferential direction. The annular surface when magnet 33 is viewed in the axial direction is a magnetic pole surface in which N poles and S poles are alternately arranged in the circumferential direction.

The pressing member 34 is an elastic member. Specifically, the pressing member 34 of the present embodiment is a coil spring formed by spirally winding a metal wire. As shown in fig. 1, the pressing member 34 is disposed radially outward of the rotary shaft 31. The pressing member 34 is inserted into the through hole 23 of the base portion 22 of the stator 20. The pressing member 34 is a compression spring disposed between the pair of

disks

32, 32 in a state of being compressed in the axial direction from the natural length. Therefore, the pressing member 34 presses (pressurizes) the pair of

disks

32, 32 in a direction separating from each other.

<1-5. Structure of Friction plate >

The pair of

friction plates

50, 50 is made of a resin material. The friction plate 50 is an annular member having a thickness in the axial direction. One friction plate 50 is located between the circular plate 32 disposed on one side in the axial direction of the stator 20 and the 1 st cover 13 in the axial direction. The other friction plate 50 is located between the disk 32 disposed on the other axial side of the stator 20 and the 2 nd cover portion 14 in the axial direction. As shown in fig. 1, the pair of

friction plates

50, 50 are arranged line-symmetrically with respect to a virtual straight line extending in the radial direction of the stator 20, with the stator 20 interposed therebetween. More specifically, the friction plates 50 of the present embodiment are fixed to the end surface not facing the stator 20, of the two end surfaces of each disk 32 in the axial direction. The friction plate 50 is disposed coaxially with the rotary shaft 31.

<1-6. Construction of bushing >

The bushing 40 is a substantially annular member having a small diameter portion 41 and a pair of large diameter portions 42. The bush 40 is disposed radially outward of the pressing member 34 and radially inward of the magnet 33. The small diameter portion 41 is a cylindrical portion and is disposed in the through hole 23 of the base portion 22 of the stator 20. Specifically, the small diameter portion 41 is disposed radially outward of the pressing member 34, the 2 nd bearing 39 is disposed radially outward of the small diameter portion 41, and the base portion 22 is disposed radially outward of the 2 nd bearing 39. The pair of large diameter portions 42 are disposed on both sides of the small diameter portion 41 in the axial direction with the small diameter portion 41 in between. The large diameter portion 42 is an annular portion. The large diameter portion 42 and the small diameter portion 41 are coaxially coupled to each other so as not to be rotatable relative to each other. The end surfaces of the large-diameter portions 42 on the opposite side to the side axially facing the base portion 22 are flat surfaces perpendicular to the central axis C and parallel to each other. The end face of the disk 32 can come into surface contact with the planar end face.

The bush 40 is axially sandwiched by the pair of

circular plates

32, 32. The bushing 40 has a through hole penetrating in the axial direction in the axial center portion. A rotating shaft 31 is inserted into the through hole with a pressing member 34 interposed therebetween.

As described above, the motor 100 with a brake according to embodiment 1 includes the housing 10, the stator 20 as a fixed body, the rotor 30 as a rotating body, and the pair of friction plates 50. The rotor 30 includes a rotating shaft 31, a pair of

disks

32 and 32, a pair of magnets 33, and a pressing member 34. In the brake-equipped motor 100 having such a configuration, when the coil is energized, the stator 20 is energized with magnetic flux, and an attraction force is generated to attract the magnet 33 toward the stator 20. The attractive force becomes stronger than the pressing force of the pressing member 34, and the magnet 33 moves toward the stator 20 as shown in fig. 1. Then, the rotor 30 rotates in the circumferential direction as the magnetic flux of the stator 20 changes.

On the other hand, when the energization of the motor 100 with a brake is cut off, the attraction force between the stator 20 and the magnet 33 disappears. Therefore, as shown in fig. 3, the

disks

32 and 32 move in directions away from each other in accordance with the pressing force of the pressing member 34, and come into contact with the inner surface of the casing 10. As a result, the rotation of the rotor 30 is restricted by the braking force generated between the

friction plates

50, 50 and the inner surface of the housing 10. Thus, the rotation/stop of the motor and the opening/closing of the brake can be simultaneously realized with a small number of parts, and further, the reduction in size, weight, and manufacturing cost of the brake-equipped motor 100 can be facilitated.

In the motor 100 with a brake according to the present embodiment, the pair of circular plates 32 (magnets 33) are disposed not only on one side of the stator 20 but also on both sides of the stator 20 in the axial direction, and therefore, the motor can strongly output rotation. Further, since the pair of friction plates 50 is provided not only on the inner side surface of one side of the housing 10 but also on the inner side surfaces of both sides of the housing 10, an excellent braking force can be exerted.

The motor 100 with a brake according to the present embodiment includes the bush 40. This can stably maintain the axial distance between magnet 33 and stator 20 when rotor 30 rotates in the circumferential direction in accordance with the change in magnetic flux of stator 20. Thus, the rotor 30 can be efficiently rotated.

In the brake-equipped motor 100 according to the present embodiment, the friction plates 50 are fixed to the end surface that does not face the stator 20, out of the two end surfaces of the circular plate 32 in the axial direction. Thus, both the magnet 33 and the friction plate 50 can be disposed on the radially outer end surface of the circular plate 32. Therefore, the area of the magnetic pole surface of the magnet 33 can be increased, and the inertia of the rotor 30 can be increased by increasing the diameter of the friction plate 50. As a result, more powerful rotation can be output, and stability toward circumferential rotation can be improved.

In the brake-equipped motor 100 according to the present embodiment, the outer peripheral surface of the stator 20 is fixed to the inner peripheral surface of the cylindrical portion 11. This makes it easy to secure a space for disposing the disk 32 on both sides of the stator 20 in the axial direction. As a result, the components can be reasonably arranged within the housing 10.

In the brake-equipped motor 100 according to the present embodiment, the 1 st bearing 61 is disposed between the inner peripheral surface of the housing 10 and the outer peripheral surface of the rotary shaft 31. Specifically, the 1 st bearing 61 is a ball bearing, and the inner race is fixed to the outer peripheral surface of the rotary shaft 31, and the outer race is fixed to the inner peripheral surfaces of the housings 10 of the 1 st cover part 13 and the 2 nd cover part 14. The end surface of the first 1 st bearing 61 on one side in the axial direction among the pair of first 1 st bearings 61 on the other side in the axial direction is disposed at a position closer to the one side in the axial direction than the inner side surface of the housing 10. Further, an end surface of the other axial side 1 of the pair of 1 st bearings 61 in the 1 st bearing 61 in the axial direction is disposed at a position further toward the other axial side than the inner surface of the housing 10. Thus, the disk portion 32 and the 1 st bearing 61 are always in a non-contact state, and therefore the pressing force of the pressing member 34 does not act on at least the 1 st bearing 61 all the time. Therefore, the rotation resistance of the 1 st bearing 61 does not occur, which leads to a decrease in the motor efficiency.

In the motor 100 with a brake according to the present embodiment, the 2 nd bearing 39 is provided between the inner peripheral surface of the through hole 23 of the base portion 22 of the stator 20 and the outer peripheral surface of the small diameter portion 41 of the bush 40. The 2 nd bearing 39 is a ball bearing, and has an inner ring fixed to the outer peripheral surface of the small diameter portion 41 of the bush 40 and an outer ring fixed to the inner peripheral surface of the through hole 23 of the base portion 22 of the stator 20. Thereby, the axial and radial positional relationship between the stator 20 and the bush 40 is maintained by the 2 nd bearing 39. In other words, the liner 40 can be positioned relative to the stator 20.

In the motor 100 with a brake according to the present embodiment, the bush 40 is made of a resin material. Therefore, the impact sound generated when the rotor 30 moves in the axial direction at the time of starting and stopping the motor can be reduced.

In the motor 100 with a brake according to the present embodiment, the bush 40 has the small diameter portion 41 and the large diameter portion 42. When the stator 20 is energized, the planar end surface of the large diameter portion 42 comes into surface contact with the end surface of the circular plate 32. In this way, the end surface of the large diameter portion 42 contacts the end surface of the circular plate 32, whereby the posture of the rotor 30, that is, the right angle of the rotor 30 with respect to the axial center can be easily maintained in an appropriate state.

<2 > embodiment 2 >

The structure of the motor 200 with a brake according to embodiment 2 will be described below with reference to fig. 4. Fig. 4 is a longitudinal sectional view of a motor 200 with a brake according to embodiment 2. In the following, the same reference numerals as those in embodiment 1 are given to members having the same functions and configurations as those in embodiment 1, and redundant description thereof is omitted. The brake-equipped motor 200 according to embodiment 2 differs from the brake-equipped motor 100 according to embodiment 1 mainly in the following points: (1) a friction plate 150 instead of the friction plate 50; (2) a circular plate 132 is provided instead of the circular plate 32; (3) no 2 nd bearing 39; and (4) a retainer ring 138.

The motor 200 with a brake according to the present embodiment includes a pair of

friction plates

150, 150. The friction plate 150 is fixed to the inner side surface of the 1 st cover part 13 and the inner side surface of the 2 nd cover part 14. The friction plate 150 is annular and has a constant thickness in the axial direction. The friction plate 150 is made of a resin material. The friction plate 150 is disposed coaxially with the rotary shaft 31. As described above, the brake-equipped motor 200 according to the present embodiment includes the friction plate 150 fixed to the housing 10. This reduces the inertia of the rotor 30, and improves the response of the brake-equipped motor 200 to start and stop by opening and closing the brake.

The pair of

disks

132, 132 are provided on both sides of the stator 20 in the axial direction with the stator 20 interposed therebetween. Each disk 132 has a substantially annular shape when viewed in the axial direction. The disk 132 has a through hole 133 penetrating in the axial direction in the axial center portion. The circular plates 132 have projections (boss) 134, and the projections 134 extend in the axial direction toward the paired circular plates 132 on the radially outer side of the spline 31s. Although not shown in fig. 4, a gap is provided between the inner circumferential surface of the through hole of the bush 40 and the outer circumferential surface of the boss 134 of the disc 132, so that the bush 40 and the boss 134 can slide relative to each other. Further, a gap that enables the bushing 40 to rotate in the circumferential direction with respect to the stator 20 is provided between the inner circumferential surface of the base portion 22 of the stator 20 and the outer circumferential surface of the small diameter portion 41 of the bushing 40. With the above configuration, in the motor 200 with a brake according to the present embodiment, the bush 40 can be rotated with respect to the stator 20 without using the 2 nd bearing 39.

The brake-equipped motor 200 according to the present embodiment includes a pair of retaining

rings

138, 138 attached to the rotary shaft 31. The pair of retaining

rings

138, 138 are attached to the rotary shaft 31 with a gap therebetween in the axial direction. The retainer ring 138 restricts the movement of the circular plate 132 in a direction to approach the circular plate 132 paired therewith. The motor 200 with a brake according to the present embodiment is configured as described above to position the rotor 30 (circular plate 132) relative to the stator 20 in the axial direction.

In the brake-equipped motor 200 according to the present embodiment, the gap adjustment member 162 is provided between the 1 st bearing 61 and the inner surface of the 1 st lid portion 13 in the axial direction. This enables the position of the rotor 30 in the axial direction with respect to the stator 20 to be adjusted after assembly, thereby improving the accuracy of assembly of the components of the brake-equipped motor 200.

<2-1 > modification of embodiment 2 >

In the example shown in fig. 4, the rotation shaft 31 does not penetrate the 1 st lid portion 13. However, instead of this, the rotation shaft may axially penetrate the 1 st and 2 nd cover portions. In this case, the rotary shaft may have a hollow portion that penetrates the shaft center portion in the axial direction. In the case of such a configuration, a wire for connecting an external power source and a coil wound around the stator 20 or another wire can be inserted into the hollow portion. Therefore, various wiring arrangements are facilitated.

<3 > embodiment 3 >

The structure of the brake-equipped motor 300 according to embodiment 3 will be described below with reference to fig. 5. Fig. 5 is a longitudinal sectional view of the motor 300 with a brake according to embodiment 3. In the following, the same reference numerals as those in embodiments 1 to 2 are given to the same components having the same functions and configurations as those in embodiments 1 to 2, and redundant description thereof is omitted. The brake-equipped motor 300 according to embodiment 3 differs from the brake-equipped

motors

100 and 200 according to embodiments 1 to 2 mainly in the following points: (1) comprises a cover member 310; and (2) electronic equipment is mounted in the internal space of the cover member 310.

The cover member 310 includes: a cylindrical body portion 311 extending in the axial direction; and a disc-shaped closing portion 312 extending radially inward from one end portion of the body portion 311 in the axial direction. The other end of the body 311 in the axial direction is connected to the outer peripheral surface of the 1 st lid 13. Thereby, the cover member 310 covers the 1 st lid portion 13 from one axial side. The cover part 310 has an internal space S0 for accommodating an electronic device therein.

The rotary shaft 31 axially penetrates the 1 st lid portion 13. An encoder 320 is attached to one end of the rotating shaft 31 in the axial direction. The encoder 320 is accommodated in the inner space S0. Although not shown in fig. 5, a sensor such as a strain sensor, an actuator, and the like may be accommodated in the internal space S0.

As described above, the brake-equipped motor 300 according to embodiment 3 includes the cover member 310. An encoder 320 and the like are mounted in the internal space S0 of the cover member 310. Thus, an electronic device such as the encoder 320 is mounted on an end portion on which a load is less likely to act on the side opposite to the side on which the torque acts, among the end portions of the rotating shaft 31. Therefore, the risk of insufficient mechanical strength is small. Wiring related to electronic devices such as the encoder 320 can be collected near the cover member 310. As a result, the arrangement can be prevented from being complicated, and further reduction in weight and manufacturing cost can be expected.

<4 > embodiment 4 >

The following describes the structure of a drive device 400 with a brake according to embodiment 4 with reference to fig. 6. Fig. 6 is a longitudinal sectional view of the brake-equipped drive device 400 according to embodiment 4. Fig. 7 is a schematic view of a part of the brake-equipped drive device 400 according to embodiment 4 as viewed in the axial direction. Fig. 8 is a cross-sectional view of the planetary reduction mechanism provided in the brake-equipped drive device 400 according to embodiment 4, as viewed in the axial direction.

In the following, the same components as those in embodiments 1 to 3 are denoted by the same reference numerals as in embodiments 1 to 3, and redundant description thereof is omitted.

The brake-equipped drive device 400 according to the present embodiment includes a motor 401 and a planetary reduction mechanism 459. The motor 401 rotates the rotating body with respect to the fixed body by the action of the magnetic flux between the fixed body and the rotating body, and inputs the rotation to the planetary reduction mechanism 459. The planetary reduction mechanism 459 reduces the speed of the input rotation and outputs the rotation. The brake-equipped drive device 400 includes a brake mechanism for stopping the rotation of the rotating body with respect to the fixed body. The brake-equipped drive device 400 includes a housing 410 and a partition 419.

<4-1. Structure of housing and partition >

The housing 410 is a case that accommodates therein other components constituting the drive device 400 with a brake. The housing 410 includes a 1 st cylinder (cylinder) 411 and a 2 nd cylinder (cylinder) 412, a flange 414, and a lid 413.

The 1 st cylinder portion 411 is a cylindrical portion extending in the axial direction. The 2 nd cylindrical portion 412 is a cylindrical portion extending in the axial direction. The radial dimension of the 2 nd cylinder part 412 is smaller than the radial dimension of the 1 st cylinder part 411. The lid 413 closes one axial side of the 1 st cylinder 411. The lid 413 has a substantially disk shape as viewed in the axial direction. The cover 413 has a through hole penetrating in the axial direction in the axial center portion. An end portion on one side in the axial direction of the shaft portion 492, which will be described later, is inserted into the through hole.

The flange 414 extends radially outward from one axial end of the 2 nd cylindrical portion 412. The flange portion 414 has a square shape as viewed in the axial direction. One end surface of the flange 414 in the axial direction overlaps with the other end surface of the 1 st cylinder 411 in the axial direction, and are fixed to each other by a fastening member 415 such as a bolt. An outer peripheral portion of a substantially disk-shaped partition portion 419 is fixed to one axial end surface of the flange portion 414. The partition 419 has a disc shape when viewed in the axial direction. The partition 419 has a through hole penetrating in the axial direction in the axial center portion.

The partition 419 partitions a space inside the 1 st cylinder 411 and the 2 nd cylinder 412 of the housing 410 in the radial direction into a 1 st space S1 on one axial side and a 2 nd space S2 on the other axial side. In the 1 st space S1, a motor 401 of the brake-equipped drive device 400 and a brake mechanism are disposed. In the 2 nd space S2, the planetary reduction mechanism 459 of the brake-equipped drive device 400 is arranged.

<4-2. Structure of planetary reduction mechanism >

The planetary reduction mechanism 459 of the brake-equipped drive device 400 is a reduction mechanism of a wave gear type. Specifically, the planetary reduction mechanism 459 includes a rigid internal gear (rigid ring) 460, a flexible external gear (rotating body) 470, a wave generator (input member) 480, and an output member 490.

The rigid internal gear 460 is annular and is fixed to the inner circumferential surface of the 2 nd cylindrical portion 412 of the housing 410 so as not to be relatively rotatable. The rigid internal gear 460 has internal teeth (internal contact portions) 461 on its inner peripheral portion. The internal teeth are arranged in plurality at a fixed pitch in the circumferential direction.

The circular flexible externally toothed gear 470 of the present embodiment is a cup shape having a circular flexible tooth 471 and a mounting portion 472. The circular flexible external gear 470 is disposed radially inward of the circular rigid internal gear 460.

The flexible teeth 471 are a portion that can be flexibly deformed into a non-perfect circle (ellipse). The rigidity of the flexible teeth 471 is much less than the rigidity of the rigid inner gear 460. That is, the rigid inner gear 460 can be substantially regarded as a rigid body. As shown in fig. 8, the flexible teeth 471 are cylindrical and have external teeth (external contact portions) 473 on the outer peripheral portion. The external teeth 473 are arrayed in plurality at regular intervals in the circumferential direction. The outer teeth 473 can mesh with (contact with) the inner teeth 461. The number of teeth of the outer teeth 473 is slightly different from the number of teeth of the inner teeth 461.

The diaphragm portion expands radially inward from an end portion on one side (the other side) of the cylindrical portion of the circular helical external gear 470 opposite to the helical tooth portion 471 in the axial direction. As shown in fig. 6, an annular attachment portion 472 having a thickness in the axial direction is disposed radially inward of the diaphragm portion. The mounting portion 472 has a rigidity much greater than that of the flexible tooth portion 471. An output member 490, which will be described later, can be attached to the attachment portion 472.

The wave generator 480 is disposed radially inward of the flexible tooth portions 471 of the circular flexible external gear 470. Specifically, the wave generator 480 is constituted by an elliptical cam 481, a flexible ball bearing 482, and the like.

The output member 490 has a mounted portion 491 and a shaft portion 492. The mounted portion 491 is a substantially disk-shaped portion. The attached portion 491 is attached to the attachment portion 472 by fixing an end surface of the attached portion 491 in one axial direction to the attachment portion 472. The shaft portion 492 is a cylindrical portion extending in the axial direction. The shaft portion 492 is provided coaxially with the mounted portion 491. The shaft portion 492 extends from one axial end surface of the attached portion 491 toward one axial side. In the present embodiment, the attached portion 491 and the shaft portion 492 are a single member. The shaft portion 492 is disposed radially inward of a rotary shaft 431 described later.

In the planetary reduction mechanism 459 configured as above, when the rotary shaft 431 rotates about the center axis C, the elliptical cam 481 of the wave generator 480 also rotates at the same rotational speed as the rotary shaft 431. Thereby, the position of the major axis of the ellipse of the elliptical cam 481 is displaced in the circumferential direction. Accordingly, the flexspline 471 of the flexspline external gear 470 is flexurally deformed into an elliptical shape by the flexspline ball bearing 482. Thus, the outer teeth 473 and the inner teeth 461 partially mesh at the position of the major axis of the ellipse. As the rotation shaft 431 rotates, the meshing position (contact position) between the circular flexible externally toothed gear 470 and the circular rigid internally toothed gear 460 changes in the circumferential direction around the center axis C. Here, since the external teeth 473 and the internal teeth 461 have different numbers of teeth, the flexible externally toothed gear 470 rotates relative to the rigid internally toothed gear 460 by an amount corresponding to the difference in the number of teeth for every 1 rotation of the meshing position. When the circular flexible external gear 470 rotates relatively, the output member 490 attached to the attachment portion 472 of the circular flexible external gear 470 also rotates at the same rotational speed as the circular flexible external gear 470. Thus, the decelerated rotation is output.

<4-3. Structure of Motor and brake mechanism >

The motor 401 of the brake-equipped drive device 400 includes the stator 20, the rotor 30, the pair of

friction plates

150 and 150, the bush 40, the gap adjustment member 162, the cover member 310, and the encoder 320. The rotor 30 includes a rotating shaft 431, a pair of

disks

32 and 32,

magnets

33 and 33, and a pressing member 34.

The rotation shaft 431 is a substantially cylindrical portion extending in the axial direction. The rotary shaft 431 is disposed coaxially with the center axis C of the brake actuator 400. As shown in fig. 7, the rotary shaft 431 has a spline 431s on an outer peripheral surface of a part in the axial direction.

As shown in fig. 6, the elliptical cam 481 of the wave generator 480 is coaxially coupled to the rotary shaft 431 in a relatively non-rotatable manner. In the present embodiment, the elliptical cam 481 and the rotary shaft 431 are a single member.

In the brake-equipped drive device 400 having such a configuration, when the coil of the motor 401 is energized, the stator 20 carries magnetic flux, and an attraction force is generated to attract the magnet 33 toward the stator 20. The attractive force becomes stronger than the pressing force of the pressing member 34, and the magnet 33 moves toward the stator 20. Also, the rotor 30 rotates as the magnetic flux in the circumferential direction of the stator 20 changes. In the paper of fig. 6, the state at this time is shown at a position above the central axis C. The rotation of the rotor 30 is input to the elliptical cam 481 of the wave generator 480. The rotation of the rotor 30 is decelerated by the planetary deceleration mechanism 459 and output as the rotation of the output member 490.

On the other hand, when the energization of the coil of the motor 401 is cut off, the attraction force between the stator 20 and the magnet 33 disappears. Therefore, the disk 32 moves in a direction away from each other by the pressing force of the pressing member 34, and comes into contact with the friction plates 150 fixed to the inner surface of the cover 413 and the end surfaces of the partitions 419 of the housing 410. This case is shown in fig. 6 at a position lower than the center axis C on the paper surface. As a result, the rotation of the rotor 30 is restricted by the braking force generated between the friction plate 150 and the circular plate 32. Accordingly, the rotation of the wave generator 480 is rapidly stopped, and the rotation of the output member 490 is restricted. In this way, rotation/stop of the motor 401 and opening/closing of the brake can be simultaneously achieved with a small number of parts, and further, reduction in size and weight and reduction in manufacturing cost of the brake-equipped drive device 400 can be facilitated.

The brake-equipped drive device 400 according to the present embodiment includes the bush 40. This can stably maintain the axial distance between magnets 33 when rotor 30 rotates in the circumferential direction in accordance with the change in magnetic flux of stator 20. Thus, the rotor 30 can be efficiently rotated.

In the brake actuator 400 according to the present embodiment, the friction plate 150 is fixed to the inner surface of the cover 413, and the partition 419 is exposed to the end surface of the 1 st space S1. This can reduce the inertia of the rotor 30, and improve the response of the brake-equipped drive device 400 to start/stop by opening/closing the brake.

In the brake-equipped drive device 400 according to the present embodiment, the outer peripheral surface of the stator 20 is fixed to the inner peripheral surface of the 1 st cylindrical portion 411. This makes it easy to secure a space for disposing the disk 32 on both sides of the stator 20 in the axial direction. As a result, the components can be arranged reasonably in the housing 410.

In the brake-equipped drive device 400 according to the present embodiment, the internal teeth 461 as the internal contact portions mesh with the external teeth 473 as the external contact portions. This allows the rotation of the rotation shaft 431 to be decelerated with high accuracy by the gear-type planetary reduction mechanism.

In the brake-equipped drive device 400 according to the present embodiment, the rigid ring is the rigid internal gear 460, the rolling element is the flexible external gear 470, and the input member is the wave generator 480. This reduces the number of parts to a large reduction ratio, and thus can achieve a reduction in size and weight.

Further, the brake-equipped drive device 400 according to the present embodiment includes the 2 nd bearing 39 disposed between the inner peripheral surface of the through hole 23 of the base portion 22 of the stator 20 and the outer peripheral surface of the small diameter portion 41 of the bush 40. Thereby, the axial and radial positional relationship between the stator 20 and the bush 40 is maintained by the 2 nd bearing 39.

In the brake-equipped drive device 400 according to the present embodiment, the 3 rd bearing 375 that rotatably supports the rotation shaft 431 is provided on the radially inner side of the circular flexible externally toothed gear 470. Thus, by disposing the 3 rd bearing 375 rotatably supporting the rotation shaft 431 on the radially inner side of the circular flexible externally toothed gear 470, the space can be effectively utilized, and the brake-equipped drive device 400 can be further downsized. The pressing force of the pressing member 34 does not act on the 3 rd bearing 375. Therefore, it does not occur that the rotation resistance of the 3 rd bearing 375 decreases the motor efficiency.

The brake drive device 400 according to the present embodiment includes the 1 st bearing 61 disposed between the inner circumferential surface of the cover 413 and the outer circumferential surface of the rotary shaft 431. Thus, the pressing force of the pressing member 34 does not act on at least the 1 st bearing 61 at all times. Therefore, the efficiency of the motor does not decrease due to the rotation resistance of the 1 st bearing 61.

The brake-equipped drive device 400 according to the present embodiment includes an output member 490 and a 4 th bearing 494. The 4 th bearing 494 is disposed between the inner peripheral surface of the 2 nd cylindrical portion 412 of the housing 410 and the outer peripheral surface of the mounted portion 491 of the output member 490. Thus, the output member 490 can be fitted into the housing 410 in the radial direction, and the brake-equipped drive device 400 can be further reduced in thickness. The 4 th bearing 494 uses, for example, a cross roller bearing.

The brake-equipped drive device 400 according to the present embodiment includes the 5 th bearing 375 between the inner peripheral surface of the elliptical cam 481 of the wave generator 480 and the outer peripheral surface of the output member 490. Therefore, the wave generator 480 is supported by not only the 1 st bearing 61 but also the 5 th bearing 375, and the rotation of the rotary shaft 431 can be further stabilized. As a result, the rotor 30 can be efficiently rotated. In the present embodiment, the 3 rd bearing 375 also serves as the 5 th bearing 375.

In the brake-equipped drive device 400 according to the present embodiment, the seal member 417 is provided between the surface of the partition 419 exposed to the 2 nd space S2 and the end surface of the elliptical cam 481 on one side in the axial direction. This can prevent the lubricating oil supplied to the 2 nd space S2 for lubricating the planetary reduction mechanism 459 from reaching the 1 st space S1.

In the brake-equipped drive device 400 according to the present embodiment, the gap adjustment member 162 is provided between the inner surface of the cover 413 and the 1 st bearing 61 in the axial direction. This can improve the assembly accuracy of the components of the brake-equipped drive device 400.

In the brake-equipped drive device 400 according to the present embodiment, the rotary shaft 431 has the 1 st hollow portion 431a that penetrates the shaft center portion in the axial direction. The rotary shaft 431 axially penetrates the partition 419. The shaft portion 492 of the output member 490 is inserted into the above-described 1 st hollow portion 431a. The output member 490 has a 2 nd hollow portion 490a axially penetrating the mounted portion 491 and the axial center portion of the shaft portion 492. One end of the shaft 492 in the axial direction axially penetrates the cap 413. Thus, a wire connecting an external power source and a coil wound around the stator 20 or another wire can be inserted into the 2 nd hollow portion 490a. Therefore, various wiring arrangements are facilitated.

In the brake-equipped drive device 400 according to the present embodiment, the bush 40 is made of a resin material. This can reduce the impact sound generated by the axial movement of the rotor 30 at the start or stop of the motor 401.

<5 > embodiment 5 >

The structure of the drive device 500 with a brake according to embodiment 5 will be described below with reference to fig. 9. Fig. 9 is a longitudinal sectional view of a brake-equipped drive device 500 according to embodiment 5. In the following, the same components as those in embodiments 1 to 4 are denoted by the same reference numerals as in embodiments 1 to 4, and redundant description thereof is omitted. The differences between the drive device 500 with a brake according to embodiment 5 and the drive device 400 with a brake according to embodiment 4 are mainly as follows: (1) comprises a cover member 310; and (2) an electronic device such as an encoder 320 is provided in the cover member 310.

In the brake-equipped drive device 500 according to embodiment 5, the pair of

disks

32 and 32 are also disposed on both sides of the stator 20 in the axial direction, and therefore, the output rotation can be strongly generated. Further, since not only one but a pair of friction plates 150 is provided, excellent braking force can be exerted.

<6 > embodiment 6

The following describes a structure of a drive device 600 with a brake according to embodiment 6 with reference to fig. 10. Fig. 10 is a longitudinal sectional view of the brake-equipped drive device 600 according to embodiment 6. In the following, the same components as those in embodiments 1 to 5 in terms of functions and configurations will be denoted by the same reference numerals as those in embodiments 1 to 5, and redundant description thereof will be omitted. The differences between the drive device 600 with a brake according to embodiment 6 and the drive device 500 with a brake according to embodiment 5 are mainly as follows: the 4 th bearing 494 is a ball bearing; and a 6 th bearing 499.

In the brake-equipped drive device 600 according to the present embodiment, one axial end portion of the shaft portion 492 of the output member 490 extends to one axial side of the axial end portion of the rotary shaft 431. Further, a 6 th bearing 499 is provided between the shaft portion 492 of the output member 490 and the inner peripheral surface of the cap 413 at a position on one side in the axial direction with respect to the 1 st bearing 61. Specifically, the 6 th bearing 499 is a ball bearing, and an inner ring is fixed to the outer peripheral surface of the shaft portion 492 and an outer ring is fixed to the inner peripheral surface of the cover 413.

In the brake-equipped drive device 600 according to the present embodiment, the output member 490 is stably supported by the 4 th bearing 494 and the 6 th bearing 499 disposed at an interval in the axial direction.

<7 > embodiment 7

The structure of a drive device 700 with a brake according to embodiment 7 will be described below with reference to fig. 11 and 12. Fig. 11 is a longitudinal sectional view of a brake-equipped drive device 700 according to embodiment 7. Fig. 12 is a cross-sectional view of the planetary reduction mechanism provided in the brake-equipped drive device 700 according to embodiment 7, as viewed in the axial direction.

In the following, the same components as those in embodiments 1 to 6 are denoted by the same reference numerals as those in embodiments 1 to 6, and redundant description thereof will be omitted. The driving device 700 with a brake according to embodiment 7 differs from the driving device 400 with a brake according to embodiment 4 mainly in that a planetary reduction mechanism 759 is provided in place of the planetary reduction mechanism 459.

The planetary reduction mechanism 759 is an eccentric oscillating reduction mechanism. Specifically, the planetary reduction mechanism 759 includes a rigid internal gear (rigid ring) 760, an external gear (rotating body) 770, an input portion 780, and an output member 490.

The input portion 780 is a substantially cylindrical portion extending in the axial direction about the center axis C of the brake-equipped drive device 700. The input portion 780 includes an eccentric portion 781, which is coaxially located with the rotation shaft 431 and coupled to the rotation shaft 431 so as not to be rotatable relative thereto. In the present embodiment, the rotating shaft 431 and the eccentric portion 781 are a single member.

The eccentric portion 781 rotates together with the rotation shaft 431 at the same rotation speed as the rotation shaft 431. The eccentric portion 781 is provided on the other side of the input portion 780 in the axial direction. The eccentric portion 781 has a cylindrical outer peripheral surface centered on an eccentric axis D extending in parallel with the central axis C at a position offset from the central axis C. When the input portion 780 rotates about the central axis C, the position of the eccentric axis D moves in the circumferential direction about the central axis C. At this time, the eccentric portion 781 rotates around the central axis C.

In the present embodiment, the two eccentric portions 781 are arranged side by side in the axial direction. The positions of the eccentric axes D of the two eccentric portions 781 are arranged rotationally symmetrically to each other with respect to the central axis C. This can suppress the fluctuation of the center of gravity caused by the rotation of the eccentric portion 781.

The rigid internal gear 760 of the present embodiment is a part of the 2 nd cylindrical part 412. Rigid internal gear 760 is annular. The rigid internal gear 760 has internal teeth (internal contact portions) 761 on its inner peripheral portion. A plurality of internal teeth 761 are arranged at a fixed pitch in the circumferential direction.

The external gear 770 has an annular shape having a constant thickness in the axial direction. The external gear 770 is disposed radially inward of the rigid internal gear 760 and radially outward of the input portion 780 and the eccentric portion 781. Bearing 775 is provided between eccentric portion 781 and external gear 770. External gear 770 is supported by bearing 775 so as to be rotatable about eccentric axis D. The outer peripheral portion of the external gear 770 has external teeth (external contact portions) 771. The external teeth 771 are arranged at a constant pitch in the circumferential direction. The number of teeth of the outer teeth 771 is slightly different from that of the inner teeth 761.

The external gear 770 has a plurality of through holes (mounting portions) 772. Each through hole 772 penetrates the external gear 770 in the axial direction. The plurality of through holes 772 are arranged at equal intervals in the circumferential direction around the eccentric axis D.

When the input portion 780 rotates about the central axis C, the external gear 770 revolves orbitally about the eccentric axis D and about the central axis C. At this time, the external gear 770 revolves while changing the meshing position of the external teeth 771 and the internal teeth 761 in the circumferential direction. At this time, the external teeth 771 meshing with the internal teeth 761 at the same position of the rigid internal gear 760 are shifted in position by the difference in the number of teeth for each revolution of the external gear 770. Accordingly, the position of the through hole 772 of the external gear 770 rotates at the decelerated rotation speed.

The other axial end of the plurality of wheel carrier pins 773 is fixed to the mounted portion 491. Specifically, the plurality of wheel carrier pins 773 are fixed at equal intervals in the circumferential direction around the center axis C of the mounted portion 491. Thereby, the output member 490 is constituted. The plurality of wheel carrier pins 773 are inserted into the through holes 772 of the external gear 770 with gaps, respectively. Thus, when the external gear 770 rotates at a reduced rotation speed, the carrier pin 773 is pressed against the inner peripheral surface of the through hole 772, and the attached portion 491 rotates at a reduced rotation speed also about the central axis C. Therefore, the output member 490 also rotates at the decelerated rotation speed.

In the brake-equipped drive device 700 having such a configuration, the rotation of the rotor 30 is regulated by the braking force generated between the friction plate 150 and the circular plate 32, and the rotation of the input portion 780 is rapidly stopped to regulate the rotation of the output member 490. Thus, the rotation/stop of the motor 701 and the opening/closing of the brake can be simultaneously realized with a small number of parts, and further, the reduction in size and weight and the reduction in manufacturing cost of the brake-equipped drive device 700 can be facilitated.

In the brake-equipped drive device 700 according to the present embodiment, the rigid ring is the rigid internal gear 760, the rotating body is the external gear 770, and the input members are the input portion 780 and the eccentric portion 781. With such a configuration, the reduction gear ratio is large and the rigidity is high, so that the reduction gear mechanism can be downsized.

<8 > embodiment 8

The following describes a structure of a drive device 800 with a brake according to embodiment 8 with reference to fig. 13 and 14. Fig. 13 is a longitudinal sectional view of a brake-equipped drive device 800 according to embodiment 8. Fig. 14 is a cross-sectional view of the planetary reduction mechanism provided in the brake-equipped drive device 800 according to embodiment 8, as viewed in the axial direction.

In the following, the same reference numerals as those in embodiments 1 to 7 are given to the same components having the same functions and configurations as those in embodiments 1 to 7, and redundant description thereof will be omitted. The brake-equipped drive device 800 according to embodiment 8 differs from the brake-equipped drive device 400 according to embodiment 4 mainly in that a planetary reduction mechanism 859 is provided instead of the planetary reduction mechanism 459.

The planetary speed reduction mechanism 859 is a planetary friction type speed reduction mechanism. Specifically, the planetary reduction mechanism 859 includes an inner ring (rigid ring) 860, a plurality of planetary wheels (rotating bodies) 870, a sun gear (input member) 880, and an output member 490.

The sun gear 880 is a substantially cylindrical portion disposed coaxially with the rotation shaft 431. In the present embodiment, the sun gear 880 and the rotary shaft 431 are a single member.

The plurality of planetary gears 870 are arranged around the sun gear 880 radially outward of the sun gear 880. In the present embodiment, five planetary gears 870 are arranged at equal intervals around the sun gear 880. However, the number of the planetary gears 870 included in the planetary reduction mechanism 459 may be 2 to 4, or 6 or more.

The planet 870 has a disc portion 871 and a shoulder 872. The disc portion 871 has a disc shape extending perpendicular to the axial direction. The shoulder portions 872 are provided on both sides of the circular plate portion 871 in the axial direction. The shoulder portion 872 has a tapered outer peripheral surface whose radial dimension is enlarged as it approaches the circular plate portion 871. The radial dimension of the shoulder portion 872 is smaller than the radial dimension of the circular plate portion 871. The shoulder portion 872 and the disk portion 871 are coaxially disposed. The outer peripheral surface of the disk portion 871 of the planetary gear 870 comes into contact with the outer peripheral surface of the sun gear 880.

A pair of inner rings 860 are provided at positions corresponding to the two shoulders 872 in the axial direction. The inner circumferential surface of the inner ring 860 on one axial side is tapered so as to converge toward one axial side. The inner circumferential surface of the inner ring 860 on the other axial side is tapered so as to converge toward the other axial side. The inner peripheral surface of the inner ring 860 contacts the outer peripheral surface of the shoulder 872 of the planet 870.

Thus, the plurality of planetary gears 870 always contact both the sun gear 880 and the inner ring 860. Therefore, when the sun gear 88 rotates, the plurality of planetary gears 870 receive power from the sun gear 880 and rotate by friction with the sun gear 880. The plurality of planetary gears 870 revolve around the sun gear 880 along the inner ring 860 by friction with the inner ring 860. At this time, the revolution speed of the planetary gear 870 is smaller than the rotation speed of the sun gear 880.

The other axial end of the plurality of wheel carrier pins 874 is fixed to the mounted portion 491. Specifically, the plurality of wheel holder pins 874 are fixed at regular intervals in the circumferential direction around the center axis C of the attached portion 491. Thereby, the output member 490 is constituted. The planetary gear 870 has a through hole 873 penetrating in the axial direction in the axial center portion. A cylindrical wheel holder pin 874 extending in the axial direction is inserted into the through hole 873. When the planet wheels 870 revolve at the decelerated rotation speed, the mounted portion 491 also rotates at the decelerated rotation speed. Therefore, the output member 490 also rotates at the decelerated rotation speed.

In the brake-equipped drive device 800 having such a configuration, the rotation of the rotor 30 is restricted by the braking force generated between the friction plate 150 and the circular plate 32, and the rotation of the sun gear 880 is rapidly stopped to restrict the rotation of the output member 490. Thus, the rotation/stop of the motor 801 and the opening/closing of the brake can be simultaneously realized with a small number of parts, and further, the reduction in size and weight and the reduction in manufacturing cost of the brake-equipped drive device 800 can be facilitated.

In the brake-equipped drive device 800 according to the present embodiment, the inner ring 860 has a friction surface 860a as an inner contact portion, and the planet wheel 870 has a friction surface 870a as an outer contact portion. The friction surface 860a as the inner contact portion is in surface contact with the friction surface 870a as the outer contact portion. This makes it possible to realize the brake-equipped drive device 800 which is silent without noise such as when gears are engaged.

In the brake-equipped drive device 800 according to the present embodiment, the rigid ring is the inner ring 860, the rotor is the planet gear 870, and the input member is the sun gear 880. Thus, since the planetary reduction mechanism 859 of the brake-equipped drive device 800 can be configured using a general-purpose machine tool, the processing cost can be reduced, and the lead time can be shortened.

In the brake-equipped drive device 800 according to the present embodiment, the seal member 417 is provided between the end surface of the partition 419 exposed to the 2 nd space S2 and the outer peripheral surface of the sun gear (input member) 880. This prevents the lubricating oil supplied to the 2 nd space S2 for lubricating the planetary reduction mechanism 859 from reaching the 1 st space S1.

<9. Embodiment 9 >

The structure of a wheel drive device 900 with a brake according to embodiment 9 will be described below with reference to fig. 15 to 17. Fig. 15 is a longitudinal sectional view of a wheel drive device 900 with a brake according to embodiment 9.

Fig. 16 is a schematic view of a part of a wheel drive apparatus 900 with a brake according to embodiment 9, as viewed in an axial direction. Fig. 17 is a view of a planetary reduction mechanism 959 provided in a braked wheel drive apparatus 900 according to embodiment 9, as viewed in an axial direction.

In the following, the same reference numerals as those in embodiments 1 to 8 are given to the same components having the same functions and configurations as those in embodiments 1 to 8, and redundant description thereof will be omitted.

The braked wheel drive device 900 according to the present embodiment includes a motor 901 and a planetary reduction mechanism 959. The wheel driving device 900 with a brake according to the present embodiment includes a hub (wheel) 905. In the motor 901, the rotating body is rotated with respect to the fixed body by the action of magnetic flux between the fixed body and the rotating body, and the rotation is input to the planetary reduction mechanism 959. The planetary reduction mechanism 959 reduces the input rotation and inputs the reduced rotation to the hub 905. The wheel driving device 900 with a brake includes a brake mechanism that stops the rotation of the rotating body with respect to the fixed body.

<9-1. Structure of planetary reduction mechanism >

The planetary reduction mechanism 959 of the wheel drive apparatus with brake 900 is a planetary friction type speed reducer. Specifically, this planetary reduction mechanism 959 includes an inner ring (rigid ring) 860, three planetary wheels (rotating bodies) 870, a sun gear (input member) 880, and an output member 990.

The output member 990 is a substantially annular member extending in the axial direction. An inner race of the 4 th bearing 494 is fixed to an outer peripheral surface of the output member 990. An outer race of the 4 th bearing 494 is fixed to an inner peripheral surface of the housing 410. Thereby, the output member 990 can relatively rotate with respect to the housing 410. The other axial end of the plurality of wheel carrier pins 874 is coupled to the output member 990. Thereby, the output member 990 rotates around the center axis C at the same rotational speed as the revolution of the carrier pin 874.

<9-2. Structure of Motor and brake mechanism >

The motor 901 of the wheel drive device 900 with a brake includes a stator 20, a rotor 30, a pair of friction plates 150, and a bush 40. The rotor 30 includes a rotating shaft 931, a pair of circular plates 32, magnets 33, and a pressing member 34.

The rotary shaft 931 is a substantially cup-shaped portion extending in the axial direction. The end portion on one side in the axial direction of the rotating shaft 931 is opened. The other axial end of the rotating shaft 931 is closed. The rotating shaft 931 has a substantially cylindrical inner space S3 along the center axis C. As shown in fig. 15 and 16, the rotary shaft 931 has a spline 931s on an outer peripheral surface of a part in the axial direction.

As shown in fig. 15, the sun gear 880 is fixed coaxially with the rotary shaft 931 so as not to be relatively rotatable.

<9-3. Structure of hub >

The hub 905 has a flange portion 906 and a wheel mounting portion 907. The flange 906 is an annular portion having a thickness in the axial direction. The flange portion 906 can be coaxially attached to the axially outer end surface of the output member 990. The wheel mounting portion 907 is a portion extending cylindrically from the outer edge of the flange portion 906 toward one side in the axial direction. The wheel mounting portion 907 is located radially outward of the planetary reduction mechanism 959. A tire (wheel) 908 can be mounted on the radially outer side of the wheel mounting portion 907.

As described above, the brake-equipped wheel drive device 900 according to the present embodiment includes the motor 901, the planetary reduction mechanism 959, and the hub 905. This enables the compact and powerful wheel drive apparatus 900 with a brake to be realized.

<10 > embodiment 10 >

The structure of a wheel drive device 1000 with a brake according to embodiment 10 will be described below with reference to fig. 18 and 19. Fig. 18 is a longitudinal sectional view of a wheel drive apparatus 1000 with a brake according to embodiment 10. Fig. 19 is a diagram showing a configuration of a planetary reduction mechanism 959 provided in a wheel drive device 1000 with a brake according to embodiment 10.

In the following, the same reference numerals as those in embodiments 1 to 9 are given to the same components having the same functions and configurations as those in embodiments 1 to 9, and redundant description thereof will be omitted.

The brake-equipped wheel drive device 1000 according to the present embodiment differs from the brake-equipped wheel drive device 900 according to the 9 th embodiment mainly in the following points: (1) a rotation shaft 1031 instead of the rotation shaft 931; (2) the lid 413 includes a shaft 413a; (3) a 7 th bearing 1007; and (4) the planetary reduction mechanism 959 has five planetary gears 870.

The rotation shaft 1031 is cylindrical and extends in the axial direction. The rotation shaft 1031 is disposed radially inward of the pressing member 34. The rotation shaft 1031 has a spline on an outer circumferential surface. The other axial end of the rotary shaft 1031 is coupled to one axial end of the sun gear 880. In the present embodiment, the rotation shaft 1031 and the sun gear 880 are a single member.

The shaft portion 413a extends cylindrically from the inner edge of the cover portion 413 toward the other axial side. The shaft portion 413a is coaxially disposed radially inward of the rotation shaft 1031.

A 7 th bearing 1007 is provided between the outer peripheral surface of the other end of the shaft portion 413a in the axial direction and the inner peripheral surface of the output member 990. The 7 th bearing 1007 is a ball bearing.

One end of the wheel mounting portion 907 in the axial direction of the present embodiment extends to the vicinity of the position where the cover 413 is disposed in the axial direction. In other words, substantially the entire planetary reduction mechanism 959 and the motor 901 of the braked wheel drive apparatus 1000 are housed in the space radially inside the wheel mounting portion 907.

As described above, the brake-equipped wheel drive device 1000 according to the present embodiment includes the motor 901, the planetary reduction mechanism 959, and the hub 905. Substantially the entire braked wheel drive device 1000 is accommodated in a space radially inside the wheel mounting portion 907 of the hub 905. Therefore, the compact and powerful wheel drive apparatus 1000 with a brake can be mounted on the vehicle without impairing the external appearance of the vehicle.

<11. Modified example >

In the above-described embodiment, the

bearings

61, 39, 375, 499, and 1007 are ball bearings, but are not limited thereto. As an alternative to the above, the bearing may be a sliding bearing, for example.

In the above-described embodiments 4 to 10, the friction plate 150 is fixed to the end surface exposed to the 1 st space S1, of the inner surface of the cover 413 and the axial end surface of the partition 419. However, it is not necessarily limited thereto. Instead of the above, the friction plates may be fixed to the end surface not facing the stator 20, of the two end surfaces in the axial direction of the circular plate 32.

In the above-described embodiments 4 to 10, the planetary reduction mechanism may be a simple planetary gear mechanism having an internal gear, a planetary gear, and a sun gear.

Also, the shapes of the detailed parts of the brake-equipped motor, the brake-equipped drive device, and the brake-equipped wheel drive device may be different from those shown in the respective drawings of the present application. Further, the respective elements appearing in the above-described embodiments or modifications may be appropriately combined within a range in which no contradiction occurs.

The present invention can be used for a motor with a brake, a drive device with a brake, and a wheel drive device with a brake, for example.

Claims

1. A motor with a brake, comprising:

a housing having a cylindrical portion extending in an axial direction, a 1 st lid portion closing one axial side of the cylindrical portion, and a 2 nd lid portion closing the other axial side of the cylindrical portion;

an annular stator having a through hole penetrating in an axial direction at an axial center portion, an outer peripheral surface of the stator being fixed to a radially inner side of the cylindrical portion of the housing; and

a rotor disposed radially inside the cylindrical portion of the housing, the rotor being provided so as to be relatively rotatable with respect to the stator,

the motor with a brake is characterized in that,

the rotor has:

a rotating shaft extending in an axial direction and inserted into the through hole of the stator;

a pair of disks provided on both sides of the stator in an axial direction with the stator interposed therebetween, the pair of disks being coupled to the rotary shaft so as to be relatively non-rotatable and slidable in the axial direction;

magnets fixed to an end surface of the circular plate, the end surface being opposite to the stator, among both end surfaces in the axial direction of the circular plate; and

a pressing member which is disposed radially outward of the rotating shaft, is inserted into the through hole of the stator, and presses the pair of disks in a direction in which the disks are separated from each other,

the motor with a brake further includes a pair of friction plates located between the circular plate disposed on one axial side of the stator and the 1 st cover portion and between the circular plate disposed on the other axial side of the stator and the 2 nd cover portion,

the brake-equipped motor further includes a bush disposed radially outside the pressing member and radially inside the magnet, the bush being sandwiched in the axial direction by the pair of disks, the bush having a through hole in an axial center portion thereof,

the bushing has:

a small diameter portion disposed inside the through hole of the stator; and

a large diameter portion provided on both sides of the small diameter portion in the axial direction with the small diameter portion interposed therebetween,

when the stator is energized, the large diameter portion is in contact with the circular plate.

2. The motor with brake of claim 1,

the friction plate is fixed to one of both end surfaces of the circular plate in the axial direction, the end surface not facing the stator.

3. The motor with brake of claim 1,

the friction plate is fixed to an inner surface of the 1 st cover part and an inner surface of the 2 nd cover part.

4. The motor with brake of claim 1,

the outer peripheral surface of the stator is fixed to the inner peripheral surface of the cylindrical portion.

5. The motor with brake of claim 1,

the motor with a brake includes a 1 st bearing, and the 1 st bearing is disposed between an inner peripheral surface of the housing and an outer peripheral surface of the rotary shaft.

6. The motor with brake of claim 5,

the motor with a brake includes a gap adjustment member between the 1 st bearing and an inner side surface of the cover in an axial direction.

7. The motor with brake of claim 1,

the circular plate has:

a through hole penetrating the shaft core; and

a protrusion extending in an axial direction from an inner edge portion of the through hole of the circular plate toward the circular plate in pair,

a clearance is provided between an inner peripheral surface of the through hole of the bush and an outer peripheral surface of the boss of the circular plate, the clearance enabling the bush and the boss to slide relative to each other.

8. The motor with brake of claim 7,

the motor with a brake has a pair of retaining rings attached to the rotating shaft to restrict the movement of the disks toward the disk pairs.

9. The motor with brake of any one of claims 1, 6, 7 and 8,

the rotating shaft axially penetrates the 1 st cover part and the 2 nd cover part,

the rotating shaft has a hollow portion axially penetrating the shaft center portion.

10. The motor with brake of any one of claims 1, 7 and 8,

the bushing is made of a resin material.

11. The motor with brake of any one of claims 1, 6, 7 and 8,

the motor with the brake is provided with a cover member which covers the 1 st cover part from one axial side and has an internal space for mounting an electronic device,

the rotating shaft penetrates the 1 st cover part along the axial direction,

at least one of an encoder, a sensor, and an actuator is mounted in the internal space.

12. A drive device with a brake, comprising:

a housing having a cylindrical portion extending in an axial direction and a lid portion closing one axial side of the cylindrical portion;

a partition portion that partitions a space on a radial direction inner side of the cylindrical portion of the housing into a 1 st space on one axial side and a 2 nd space on the other axial side;

a motor disposed in the 1 st space; and

a planetary reduction mechanism disposed in the 2 nd space,

the planetary reduction mechanism includes:

an annular rigid ring fixed to an inner peripheral surface of the housing so as not to be relatively rotatable, the rigid ring having an inner contact portion on an inner peripheral portion;

a rotating body which is disposed radially inside the rigid ring, has an outer contact portion that contacts the inner contact portion, and has a mounting portion to which an output member can be mounted; and

an input member disposed radially inward of the rolling element and rotating to change a contact position between the inner contact portion and the outer contact portion in a circumferential direction,

the motor includes:

a rotor provided so as to be relatively rotatable with respect to the stator,

the drive device with a brake is characterized in that,

the rotor has:

a pair of disks provided on both sides of the stator in an axial direction with the stator interposed therebetween, and coupled to be relatively non-rotatable with respect to the rotating shaft and slidable in the axial direction;

a pressing member that is disposed radially outward of the rotating shaft and is inserted into the through hole of the stator, the pressing member pressing the pair of disks in a direction separating from each other,

the motor further includes a pair of friction plates positioned between the circular plate and the cover portion that are arranged on one side in the axial direction of the stator and between the circular plate and the partition portion that are arranged on the other side in the axial direction of the stator,

the input member is coupled to the rotary shaft in a relatively non-rotatable manner,

the rotor further includes a bushing disposed radially outside the pressing member and radially inside the magnet, the bushing being axially sandwiched between the pair of disks, the bushing having a through hole in an axial center portion,

the bushing has:

a small diameter portion disposed inside the through hole of the stator; and

13. The drive device with brake of claim 12, characterized in that,

the friction plates are fixed to one of the two axial end surfaces of the circular plate that does not face the stator.

14. The drive device with a brake of claim 12, characterized in that,

the friction plate is fixed to an inner side surface of the cover portion and an end surface of the partition portion exposed to the 1 st space.

15. The drive device with brake of claim 12, characterized in that,

16. The drive device with brake of claim 12, characterized in that,

the internal abutment has an internal toothing,

the external abutment portion has an external toothing,

the internal teeth mesh with the external teeth.

17. The drive device with brake of claim 16, characterized in that,

the rigid ring is an internal gear which is provided with a plurality of teeth,

the rotating body is a planet wheel,

the input member is a sun gear.

18. The drive device with a brake of claim 16, characterized in that,

the rigid ring is a rigid internal gear,

the rotating body is a flexible external gear,

the input component is a wave generator.

19. The drive device with brake of claim 16, characterized in that,

the rigid ring is a rigid internal gear,

the rotating body is an external gear, and the rotating body is an external gear,

the input component is an input part and an eccentric part.

20. The drive device with a brake as claimed in any one of claims 12, 17, 18 and 19,

the inner abutting part is provided with a friction surface,

the external abutting part is provided with a friction surface,

the friction surface of the inner abutting portion is in surface contact with the friction surface of the outer abutting portion.

21. The drive device with brake of claim 20, characterized in that,

the rigid ring is an inner ring,

the rotating body is a planet wheel,

the input member is a sun gear.

22. The drive device with brake of claim 18, characterized in that,

the brake-equipped drive device includes a 3 rd bearing, and the 3 rd bearing rotatably supports the rotating shaft on a radially inner side of the circular flexible external gear.

23. The brake-equipped drive apparatus according to any one of claims 12, 17, 18, 19, 21 and 22,

the drive device with the brake includes a 1 st bearing, and the 1 st bearing is disposed between an inner peripheral surface of the cover portion and an outer peripheral surface of the rotary shaft.

24. The drive device with a brake as claimed in claim 18 or 22,

the drive device with a brake is provided with:

an output member having: a disk-shaped mounted portion mounted on the mounting portion; and a shaft portion extending from the mounted portion toward one side in the axial direction; and

and a 4 th bearing disposed between an inner peripheral surface of the cylindrical portion of the housing and an outer peripheral surface of the attached portion.

25. The drive device with a brake of claim 24, characterized in that,

a5 th bearing is provided between an inner peripheral surface of the input member and an outer peripheral surface of the shaft portion of the output member.

26. The brake-equipped drive apparatus according to any one of claims 12, 17, 18, 19, 21, 22 and 25,

a sealing member is provided between an end surface of the partition portion exposed to the 2 nd space and an end surface of the input member on one side in the axial direction or an outer peripheral surface of the input member.

27. The drive device with brake of claim 23, characterized in that,

the drive device with the brake includes a gap adjustment member disposed between an inner side surface of the cover portion and the 1 st bearing in an axial direction.

28. The drive device with brake of claim 24, characterized in that,

the rotating shaft has a 1 st hollow part axially penetrating the shaft center part, the rotating shaft axially penetrates the partition part,

the shaft portion of the output member is inserted into the 1 st hollow portion,

the output member has a 2 nd hollow portion axially penetrating the attached portion and the axial center portion of the shaft portion,

one end of the shaft portion in the axial direction penetrates the cover portion in the axial direction.

29. The drive device with a brake of claim 12, characterized in that,

the bushing is composed of a resin material.

30. A braked wheel drive apparatus including the brake drive apparatus according to any one of claims 12, 17, 18, 19, 21, 22, 25, 27 and 28,

further provided is a hub having:

an annular flange portion that can be attached to the other axial end surface of the output member; and

and a wheel mounting portion that extends in a cylindrical shape from an outer edge of the flange portion toward one side in the axial direction, covers a part or the whole of the housing, and is capable of mounting a wheel on a radially outer side.