CN111684175A

CN111684175A - Wheel module and moving mechanism

Info

Publication number: CN111684175A
Application number: CN201980010324.4A
Authority: CN
Inventors: 角友纪; 古崎浩幸; 小山高延; 土屋英彦
Original assignee: MinebeaMitsumi Inc
Current assignee: MinebeaMitsumi Inc
Priority date: 2018-01-30
Filing date: 2019-01-22
Publication date: 2020-09-18
Anticipated expiration: 2039-01-22
Also published as: WO2019151033A1; CN111684175B

Abstract

According to an embodiment, a wheel module includes: a gear mechanism for reducing the rotation speed of the motor; a bearing portion into which a rotating shaft of the gear mechanism is inserted; a support portion supporting the bearing portion; and an elastic member disposed in a gap formed between the outer wall of the bearing portion and the inner wall of the support portion, and abutting against the outer wall of the bearing portion and the inner wall of the support portion.

Description

Wheel module and moving mechanism

Technical Field

The invention relates to a wheel module and a moving mechanism.

Background

Conventionally, in a wheel module having a planetary gear mechanism for reducing the rotation speed of a drive motor, it is known that a planetary gear is supported by a carrier via a coupling pin (for example, see patent document 1).

Patent document 1: japanese patent laid-open No. 2008-17588

However, in the above-described technique, vibration generated by meshing of gears in the gear mechanism may be transmitted to other members such as a housing, and noise may be generated.

Disclosure of Invention

The present invention has been made in view of the above-described problems, and an object thereof is to provide a wheel module and a moving mechanism that reduce propagation of vibration caused by engagement of gears.

A wheel module according to an aspect of the present invention includes: a gear mechanism for reducing the rotation speed of the motor; a bearing portion into which a rotating shaft of the gear mechanism is inserted; a support portion for supporting the bearing portion; and an elastic member disposed in a gap formed between an outer wall of the bearing portion and an inner wall of the support portion, the elastic member being in contact with the outer wall of the bearing portion and the inner wall of the support portion.

According to one aspect of the present invention, it is possible to provide a wheel module and a moving mechanism that reduce propagation of vibration caused by engagement of gears.

Drawings

Fig. 1 is a perspective view showing an external appearance of a carriage including a wheel module.

Fig. 2 is a perspective view showing an external appearance of the wheel module.

Fig. 3 is a perspective view showing an external appearance of the wheel module.

Fig. 4 is an exploded view of a portion of the wheel module of fig. 3.

Fig. 5 is a cross-sectional view of the wheel module in the axial direction.

Fig. 6 is a cross-sectional view VI-VI of fig. 5.

Fig. 7 is a cross-sectional view showing a part of the wheel module in the axial direction including the bolt.

Fig. 8 is an enlarged view of the vicinity of the planetary gear of fig. 5.

Fig. 9 is a perspective view of the second fixing member and the bearing portion as viewed from the front side.

Fig. 10 is an exploded view of fig. 9.

Fig. 11 is a perspective view of a wheel module according to a modification.

Fig. 12 is an enlarged cross-sectional view of the vicinity of the second bearing portion of the wheel module according to the modification.

Fig. 13 is an enlarged cross-sectional view of the vicinity of the second bearing portion of the wheel module according to the modification.

Detailed Description

Hereinafter, the wheel module and the moving mechanism according to the embodiment will be described with reference to the drawings. In the drawings referred to in the following description, the dimensional relationship, ratio, and the like of the elements may be different from those of the actual elements. In addition, there are cases where the drawings include portions having different dimensional relationships and ratios from each other. In the drawings, the same reference numerals are given to the components that perform the same function.

As shown in fig. 1, the cart 100 has an object stage 110, a handle 120, and a wheel module 200. Fig. 1 is a perspective view showing an external appearance of a carriage 100 including a wheel module 200 according to an embodiment. The stage 110 constitutes a body.

The stage 110 is a thick plate-like member, and loads are placed on the surface thereof. The handle 120 is a curved rod-shaped member that the user holds when moving the carriage 100, and is attached to the upper surface of the stage 110. The wheel module 200 is a wheel that rotates by a driving current supplied from a power source, not shown, and is attached to the back surface of the stage 110.

The wheel module 200 is used as a moving mechanism of the cart 100. For example, the wheel module 200 is driven in an auxiliary use when the user carries a load on the stage 110 and conveys the load, or is driven according to a distance from another carriage 100 when the carriage 100 has a function of automatically traveling following the other carriage 100. The wheel module 200 may be mounted on the bogie 100 as a front wheel, may be mounted as a middle wheel, may be mounted as a rear wheel, or may be mounted as a combination of two or more of the front wheel, the middle wheel, and the rear wheel. For example, in the case of a six-wheeled carriage, the turning performance is high, but the number of wheels to be mounted is not limited to four wheels or the like.

The wheel module 200 can also be used as a moving mechanism of a so-called service robot such as a transport/conveyance robot or a cleaning robot.

As shown in fig. 2 to 5, the wheel module 200 includes a connection member 210 and a wheel portion 220. Fig. 2 is a perspective view showing an external appearance of the wheel module 200. Fig. 3 is a perspective view showing an external appearance of the wheel module 200. Fig. 4 is an exploded view of a portion of the wheel module 200 of fig. 3. Fig. 5 is a sectional view of the wheel module 200 in the axial direction. In fig. 3 and 4, the tire 10 is omitted. The wheel module 200 may be configured by only the wheel portion 220.

In the present embodiment, an example will be described in which the wheel module 200 is attached to the vicinity of the end portion of the rear surface of the stage 110 included in the carriage 100, and the wheel unit 220 is disposed outside the support member 41 b. Therefore, in the following description, in the axial direction (hereinafter, referred to as the "axial direction") of the rotation shaft of the wheel module 200, the side closer to the inside of the carriage 100 is referred to as the "depth side", and the side closer to the outside of the carriage 100 is referred to as the "front side". The vertical direction is referred to as "lower", and the direction opposite to the vertical direction is referred to as "upper". Further, the radially outer side of the wheel body 11 of the wheel module 200 may be referred to as a "radially outer side", and the radially inner side may be referred to as a "radially inner side".

The coupling member 210 is attached to the rear surface of the stage 110 of the carriage 100 and supports the wheel unit 220. The connecting member 210 is formed in a substantially L shape when viewed from the axial direction. The connection member 210 includes a fixing portion 1, a column portion 2, a first holding portion 3, and a second holding portion 4. The fixing portion 1, the pillar portion 2, and the first holding portion 3 are integrally formed. The fixing portion 1, the pillar portion 2, and the first holding portion 3 may be formed as separate bodies. The fixing portion 1 is formed in a thick plate shape and attached to the back surface of the stage 110. The column part 2 extends downward from the end part on the depth side of the fixing part 1.

The first holding portion 3 is provided at the lower end of the column portion 2 and extends in a direction orthogonal to the axial direction and the extending direction of the column portion 2. A first clamping portion 3a and a first feeder line holding portion 3b are formed on the lower surface of the first holding portion 3.

The first clamping portion 3a is formed in a semicircular arc shape recessed upward and is formed along the axial direction. The first clamping portion 3a is formed to clamp the support member 41b of the wheel portion 220. The first feeder line holding portion 3b is formed in a semicircular arc shape recessed upward and is formed along the axial direction. The first power supply line holding portion 3b is formed to hold a power supply line 221, and the power supply line 221 supplies a drive current to the wheel portion 220. The shape of the first clamping portion 3a is not limited to the above shape as long as it can clamp the support member 41 b. The first feeder line holding portion 3b is not limited to the above shape as long as it can hold the feeder line 221.

The second holding portion 4 is disposed below the first holding portion 3. The second holding portion 4 extends in a direction orthogonal to the axial direction and the extending direction of the column portion 2, similarly to the first holding portion 3. A second clamping portion 4a and a second feeder line holding portion 4b are formed on the upper surface of the second holding portion 4.

The second clamping portion 4a is formed in a semicircular arc shape recessed downward and is formed in the axial direction. The second clamping portion 4a is formed to clamp the support member 41 b. The second feeder line holding portion 4b is formed in a semicircular arc shape recessed downward and is formed in the axial direction. The second feeder line holding portion 4b is formed to hold the feeder line 221. The second clamping portion 4a is not limited to the above shape as long as it can clamp the support member 41 b. The second feeder line holding portion 4b is not limited to the above shape as long as it can hold the feeder line 221.

The second holding portion 4 is attached to the first holding portion 3 by, for example, a screw 80 in a state where the support member 41b is sandwiched between the first clamping portion 3a and the second clamping portion 4 a. Thereby, the support member 41b is sandwiched by the connection member 210, and the wheel unit 220 is attached and fixed to the stage 110.

The connection member 210 may be configured to hold the support member 41b between three or more holding portions, for example, and mount the wheel module 200 on the stage 110.

The wheel unit 220 is supplied with a drive current from a power supply, not shown, via the power supply line 221, and thereby the wheel unit 220 rotates about the rotation axis.

The wheel unit 220 includes a tire 10, a wheel 11, a driving unit 12, and a braking unit 13.

The tire 10 is a cylindrical member formed of rubber or the like and having elasticity. Here, for example, the tire 10 has a diameter of 100 to 300 mm. The wheel body 11 is formed in a cylindrical shape, and the tire 10 is mounted on the outer circumferential side.

The driving portion 12 is disposed inside the wheel 11, specifically, radially inside the wheel 11, and is driven by an electric current supplied through the power supply line 221 to rotate the wheel 11 about the rotation axis. The drive unit 12 includes a stator 15, a rotor 16, a rotary shaft 17, a planetary gear mechanism 18, and a housing 19.

The stator 15 and the rotor 16 constitute an inner rotor type motor, and the rotor 16 rotates about a rotation axis by a drive current. The rotational force generated by the rotation of the rotor 16 is transmitted to the wheel 11 via the rotary shaft 17 and the planetary gear mechanism 18. Thereby, the tire 10 rotates together with the wheel body 11.

The stator 15 rotates the rotor 16 around the rotation axis by the drive current. Specifically, the stator 15 has a structure in which a plurality of salient poles are arranged in a circumferential direction on an inner circumferential surface of a stator base portion formed in a hollow cylindrical shape, and a coil is wound around each salient pole.

The rotor 16 is disposed radially inward of the stator 15, and rotates about a rotation axis with respect to the stator 15, thereby rotating the wheel 11. Specifically, the rotor 16 has a structure in which a plurality of magnets are arranged in a circumferential direction along the outer peripheral surface of a base portion formed in a columnar shape, and each magnet is arranged so as to face each coil of the stator 15. As a result, the rotor 16 rotates about the rotation axis by an electromagnetic force generated in the coil when the driving current flows through the coil of the stator 15.

The rotating shaft 17 is disposed so that its axial center coincides with the rotating shaft, and is fixed to the rotor 16 in a state of penetrating the center of the rotor 16. Here, the rotary shaft 17 is rotatably supported by the second fixing member 42 of the housing 19 via a bearing 60 disposed on the deeper side than the rotor 16 and a bearing 61 disposed on the forward side than the rotor 16. Thereby, the rotary shaft 17 rotates about the rotary shaft in accordance with the rotation of the rotor 16.

As shown in fig. 6, the planetary gear mechanism 18 includes a sun gear 18a, three planetary gears 18b, and an internal gear 18c disposed so as to surround the three planetary gears 18 b. Fig. 6 is a cross-sectional view VI-VI of fig. 5.

The planetary gear 18b is integrated with the rotary shaft 18 d. The planetary gear 18b is meshed with the sun gear 18a, and rotates about the rotation shaft 18d together with the rotation shaft 18 d. Further, the internal gear 18c meshes with the three planetary gears 18 b. Returning to fig. 5, a sun gear 18a is formed at the end portion on the near side of the rotary shaft 17. One end of the planetary gear 18b is rotatably supported by the second fixing member 42 of the housing 19 via an end of the first bearing portion 20 a. The other end of the planetary gear mechanism 18 is rotatably supported by the third fixing member 43 of the housing 19 via the end of the second bearing portion 20 b. The details of the rotation shaft 18d of the planetary gear 18b and the support mechanism for the rotation shaft 18d will be described later. The bearing

portions

20a and 20b are sintered oil-impregnated bearings.

The ring gear 18c is fixed to the first rotating member 31 of the housing 19 by screws (not shown) or the like.

Thus, when the rotary shaft 17 rotates in accordance with the rotation of the rotor 16, the three planetary gears 18b meshing with the sun gear 18a formed on the rotary shaft 17 rotate. Then, the internal gear 18c is fixed to the first rotating member 31 by a screw or the like, and the three planetary gears 18b rotate, whereby the internal gear 18c meshing with the planetary gears 18b rotates. The wheel 11 and the tire 10 rotate together with the rotation of the internal gear 18 c. As a result, the rotational output generated by the rotation of the rotor 16 is inversely proportional to the reduction ratio, and the rotational speed is reduced, and the torque increased in proportion to the reduction ratio is transmitted to the wheel 11 and the tire 10.

The housing 19 has a rotating member 30 and a fixed member 40. The housing 19 is disposed inside the wheel 11, and houses the brake unit 13, the stator 15, the rotor 16, the rotary shaft 17, and the planetary gear mechanism 18.

The rotating member 30 has a first rotating member 31 and a second rotating member 32. The first rotating member 31 is formed in a bottomed cylindrical shape having a bottom portion 31a on the near side and an opening on the deep side. The first rotating member 31 is attached to the wheel 11 by a screw 81 or the like. The first rotating member 31 is rotatably supported by the third fixing member 43 via a bearing 62.

A bottom portion 31a of the first rotating member 31 is formed with a protruding portion 31b protruding toward the depth side. The convex portion 31b is formed to face the rotation shaft 17. The projection 31b is inserted into a hole 43c formed in the third fixing member 43. The convex portion 31b is formed with a supply hole 31c for supplying lubricating oil and grease to the planetary gear mechanism 18. The supply hole 31c is provided with a grease nipple 33. The supply hole 31c and the grease nipple 33 constitute a supply portion.

As shown in fig. 7, a discharge hole 31d is formed in the bottom portion 31a of the first rotating member 31 radially outward of the supply hole 31 c. The discharge hole 31d is provided with a bolt 34 for opening and closing the discharge hole 31 d. The bolt 34 is detachably attached to the discharge hole 31 d. Fig. 7 is a cross-sectional view showing a part of the wheel module 200 in the axial direction including the bolt 34. The discharge hole 31d and the bolt 34 constitute a discharge portion. In addition, the bolt 34 seals the discharge hole 31 d.

The bolt 34 is attached to the discharge hole 31d to close the discharge hole 31d except for the case of discharging the degraded lubricating oil or grease and the case of supplying the lubricating oil or grease from the grease nipple 33. When the grease nipple 33 is used to supply the lubricating oil or grease to the planetary gear mechanism 18, the lubricating oil or grease is supplied from the grease nipple 33 in a state where the bolt 34 is removed from the discharge hole 31 d. This discharges air present in the second housing portion 45, which will be described later, and degraded lubricating oil grease from the discharge hole 31d, and supplies the lubricating oil grease to the planetary gear mechanism 18.

Returning to fig. 5, the second rotating member 32 is formed in a cylindrical shape. The second rotating member 32 is disposed adjacent to the first rotating member 31 in the axial direction, and is disposed on the deeper side than the first rotating member 31. The second rotating member 32 is attached to the first rotating member 31 by a screw 82 or the like. The second rotating member 32 is rotatably supported by the first fixed member 41 via a bearing 63.

The fixing member 40 is disposed radially inward of the rotating member 30. The fixing member 40 has a first fixing member 41, a second fixing member 42, and a third fixing member 43.

The first fixing member 41, the second fixing member 42, and the third fixing member 43 are arranged in the order of the first fixing member 41, the second fixing member 42, and the third fixing member 43 from the depth side to the front side in the axial direction. The fixing member 40 forms a first receiving portion 44 for receiving the driving portion 12 by the first fixing member 41 and the second fixing member 42. The fixed member 40 forms a second housing portion 45 that houses the planetary gear mechanism 18 by a part of the second rotating member 32, the second fixed member 42, and the third fixed member 43. That is, the second fixing member 42 defines a first receiving portion 44 and a second receiving portion 45. The second fixing member 42 constitutes a first wall portion. The third fixing member 43 constitutes a second wall portion.

The first fixing member 41 is formed in a bottomed cylindrical shape having a bottom portion 41a on the depth side and an opening on the front side. A support member 41b extending in the axial direction is formed on the bottom portion 41a of the first fixing member 41. The support member 41b extends from the bottom portion 41a toward the depth side. The support member 41b may be provided separately from the first fixing member 41. The first fixing member 41 constitutes a fixing-side member.

The support member 41b is formed in a cylindrical shape. A cover 41c is attached to an end of the support member 41b on the depth side. The cover 41c is formed in a bottomed cylindrical shape having a bottom on the depth side and an opening on the front side. By attaching the cover 41c to the support member 41b, a third housing portion 46 for housing the stopper portion 13 is formed on the depth side of the support member 41 b.

In addition, the support member 41b is formed with a thick portion 41 d. The thick portion 41d is formed on the bottom portion 41a side of the first fixing member 41, i.e., on the front side of the third receiving portion 46, and is formed thicker than the portion where the third receiving portion 46 is formed. The thick portion 41d is formed at a portion sandwiched by the connecting member 210. The support member 41b may have a thick portion 41d formed at least in a part of a portion sandwiched by the connection member 210. The support member 41b has the thick wall portion 41d, and therefore can improve strength.

A hole 41e into which the rotary shaft 17 is inserted is formed in the thick portion 41 d. The thick portion 41d rotatably supports the rotary shaft 17 via a bearing 60.

The second fixing member 42 is formed in a substantially circular shape. The second fixing member 42 is disposed adjacent to the first fixing member 41 in the axial direction, and is disposed on the front side of the first fixing member 41. The second fixing member 42 is attached to the first fixing member 41 by a screw 83 or the like.

The second fixing member 42 is formed with a hole 42a into which the rotary shaft 17 is inserted. A cylindrical bearing support portion 42b projecting in the axial direction toward the depth side is formed around the hole 42 a. A bearing 61 is disposed between the inner peripheral wall of the bearing support portion 42b and the outer peripheral wall of the rotary shaft 17.

A first support portion 42c that is recessed toward the depth side in the axial direction is formed on a surface of the second fixing member 42 on the near side, that is, a surface facing the planetary gear 18 b. The first support portion 42c is formed in a bottomed shape with a bottom portion 42g closed. A rotary shaft 18d integrated with the planetary gear 18b is inserted into the first support portion 42c through the first bearing portion 20 a. The first support portion 42c supports the rotation shaft 18d of the planetary gear 18b via the first bearing portion 20 a. The first support portion 42c is formed in three places in correspondence with the planetary gear 18 b. In the present embodiment, the planetary gears 18b are formed in three positions, but the wheel module 200 may be provided with one or more planetary gears. The second fixing member 42 rotatably supports the planetary gear 18 b. The first support portion 42c is described in detail later.

The third fixing member 43 includes a substrate 43a and a coupling portion 43 b. The third fixing member 43 is disposed opposite to the second fixing member 42. Specifically, the third fixing member 43 is disposed such that the base plate 43a faces the second fixing member 42 via the planetary gears 18b of the planetary gear mechanism 18.

A hole 43c into which the convex portion 31b of the first rotating member 31 is inserted is formed in the base plate 43 a. A cylindrical bearing support portion 43d projecting toward the front side in the axial direction is formed around the hole 43 c. A bearing 62 is disposed between the outer peripheral wall of the bearing support portion 43d and the inner peripheral wall of the bottom portion 31a of the first rotating member 31.

Further, a second support portion 43e recessed toward the front side in the axial direction is formed on the base plate 43a on the surface on the depth side, that is, the surface facing the planetary gear 18 b. The second support portion 43e is formed in a bottomed shape. The rotation shaft 18d of the planetary gear 18b is inserted into the second support portion 43e through the second bearing portion 20 b. The second support portion 43e is formed in three places in correspondence with the planetary gear 18 b. A hole 43g penetrating in the axial direction is formed in the bottom portion 43f of the second support portion 43 e. The second support portion 43e is described in detail later.

The coupling portion 43b protrudes from the base plate 43a toward the depth side between the adjacent planetary gears 18 b. The coupling portion 43b is attached to the second fixing member 42 by a screw 84 (see fig. 7) or the like. The coupling portion 43b is disposed radially inward of the internal gear 18c of the planetary gear mechanism 18, and does not contact the internal gear 18 c. The third fixing member 43 rotatably supports the planetary gear 18 b.

The brake portion 13 is accommodated in the third accommodating portion 46, and generates a braking force for decelerating the rotary shaft 17.

Here, the supporting structure of the planetary gear 18b of the planetary gear mechanism 18, the first supporting portion 42c of the second fixing member 42, and the second supporting portion 43e of the third fixing member 43 will be described in detail with reference to fig. 8. Fig. 8 is an enlarged view of the vicinity of the planetary gear in fig. 5.

As described above, one end of the planetary gear 18b is rotatably supported by the second fixing member 42 via the first bearing portion 20a, and the other end is rotatably supported by the third fixing member 43 via the second bearing portion 20 b. A hollow 18e is formed in the rotation shaft 18d of the planetary gear 18b in the axial direction. That is, the rotation shaft 18d of the planetary gear 18b is formed in a hollow shape. The hollow portion 18e constitutes a hollow portion.

The planet gear 18b includes

washers

52 and 53 on its end face, and the planet gear 18b is held in contact with the end faces of the first bearing portion 20a and the second bearing portion 20b via the

washers

52 and 53, leaving a gap between the rotating shaft 18d and the second and

third fixing members

42 and 43. With this configuration, the planetary gear 18b is rotatably supported.

The first bearing portion 20a is formed in a cylindrical shape, and has a rotation preventing portion 20c protruding from an end portion on the near side, i.e., the planetary gear 18b side, toward the outside in the radial direction of the first bearing portion 20 a. As shown in fig. 9 and 10, the rotation preventing portion 20c is formed in an elliptical shape. That is, the rotation preventing portion 20c has two linear outer walls 20c1 and an arc-shaped outer wall 20c2 connecting the two outer walls 20c 1. Fig. 9 is a perspective view of the second fixing member 42 and the first bearing portion 20a as viewed from the front side. Fig. 10 is an exploded view of fig. 9.

The first support portion 42c of the second fixing member 42 is formed to be recessed stepwise toward the depth side. Thus, the second fixing member 42 is formed with the first recess 42d, the second recess 42e, and the third recess 42f in this order from the depth side. That is, the first support portion 42c is formed by the first recess 42d, the second recess 42e, and the third recess 42 f. The shape of the first recess 42d in a cross section perpendicular to the axial direction is circular.

The shape of the second recess 42e in a cross section perpendicular to the axial direction is circular. The inner peripheral wall 42e1 of the first support portion 42c forming the second recess 42e has a larger diameter than the inner peripheral wall 42d1 of the first support portion 42c forming the first recess 42 d. The first support portion 42c accommodates the O-ring 50 in the second recess 42 e. The second recess 42e constitutes a recess.

The third recess 42f in a cross section perpendicular to the axial direction has an elliptical shape. That is, the third recessed portion 42f is formed by two linear inner walls 42f1 facing each other and two arc-shaped inner walls 42f2 connecting the two inner walls 42f 1. Further, the diameter of the arc-shaped inner wall 42f2 is larger than the diameter of the inner peripheral wall 42e1 forming the second recess 42 e. Further, the distance between the two linear inner walls 42f1 is larger than the diameter of the inner peripheral wall 42e1 forming the second recess 42 e.

Returning to fig. 8, the second bearing portion 20b has the same configuration as the first bearing portion 20a, and detailed description thereof is omitted. The second bearing portion 20b is formed in a cylindrical shape and has a rotation preventing portion 20 d.

The second support portion 43e formed on the base plate 43a of the third fixing member 43 is formed to be recessed stepwise toward the front side. Thus, the third fixing member 43 has a first recess 43h, a second recess 43i, and a third recess 43j formed in this order from the front side. That is, the second support portion 43e is formed by the first recess 43h, the second recess 43i, and the third recess 43 j. The shapes of the concave portions 43h to 43j are the same as those of the concave portions 42d to 42f of the second fixing member 42, and detailed description thereof is omitted. The second support portion 43e accommodates the O-ring 51 in the second recess 43 i. The second recess 43i constitutes a recess.

A hole 43g formed in a bottom portion 43f of the second support portion 43e of the third fixing member 43 is formed so as to face the hollow portion 18e of the rotary shaft 18d of the planetary gear 18 b. The hole 43g communicates with the hollow portion 18 e. The diameter of the hole 43g is smaller than the diameter of the cavity 18 e. The opening of the hole 43g on the near side is closed by a bearing 62. The bearing 62 constitutes a rotary bearing portion.

The O-

rings

50, 51 are elastic members. The O-ring 50 is disposed in a gap formed between the inner peripheral wall 42e1 of the second recess 42e forming the first support portion 42c and the outer peripheral wall 20a1 of the first support portion 20a, and abuts against the inner peripheral wall 42e1 and the outer peripheral wall 20a 1.

Thereby, a gap is formed between the inner peripheral wall 42d1 of the first recess 42d forming the first support portion 42c and the outer peripheral wall 20a1 of the first bearing portion 20 a. Further, gaps are formed between the inner walls 42f1 (see fig. 9) and 42f2 of the third recess 42f forming the first support portion 42c and the outer walls 20c1 (see fig. 9) and 20c2 of the rotation preventing portion 20c of the first bearing portion 20 a.

That is, the O-ring 50 abuts against the inner peripheral wall 42e1 and the outer peripheral wall 20a1 in a state where a gap is formed between the first support portion 42c and the first bearing portion 20 a.

The O-ring 51 is disposed in a gap formed between the inner peripheral wall 43i1 forming the second recess 43i of the second support portion 43e and the outer peripheral wall 20b1 of the second bearing portion 20b, and abuts against the inner peripheral wall 43i1 and the outer peripheral wall 20b 1.

Thereby, a gap is formed between the inner peripheral wall 43h1 of the first recess 43h forming the second support portion 43e and the outer peripheral wall 20b1 of the second support portion 20 b. Further, a gap is formed between the inner wall 43j1 of the third recess 43j forming the second support portion 43e and the outer wall 20d1 of the rotation preventing portion 20d of the second support portion 20 b.

That is, the O-ring 51 abuts against the inner peripheral wall 43i1 and the outer wall 20d1 in a state where a gap is formed between the second support portion 43e and the second support portion 20 b.

In the wheel module 200, the planetary gear 18b can be displaced in the radial direction by the elastic deformation of the O-

rings

50, 51. Therefore, the wheel module 200 can absorb the vibration generated by the engagement of the planetary gear 18b with the sun gear 18a and the ring gear 18c through the O-

rings

50, 51. Further, since the planetary gear mechanism 18 can be assembled while deforming the O-

rings

50 and 51 when assembling the planetary gear mechanism 18, it is not necessary to improve the hole position accuracy between the fixing member 42 and the fixing member 43 at the time of assembly.

Next, the procedure of assembling the planetary gear 18b of the planetary gear mechanism 18 will be described.

When the planetary gear 18b is assembled, first, the O-ring 50 is attached to the outer peripheral wall 20a1 of the first bearing portion 20a, and the first bearing portion 20a to which the O-ring 50 is attached is inserted into the first support portion 42c of the second fixing member 42. Thereby, the O-ring 50 is accommodated in the second recess 42 e.

Next, the O-ring 51 is attached to the outer peripheral wall 20b1 of the second bearing portion 20b, and the second bearing portion 20b to which the O-ring 51 is attached is inserted into the second support portion 43 e. Thereby, the O-ring 51 is accommodated in the second recess 43 i.

Subsequently, the rotating shaft 18d is press-fitted into the planetary gear 18 b. Thereby, the planetary gear 18b and the rotary shaft 18d are integrated. Then, the rotation shaft 18d is inserted into the first bearing portion 20a, and the first bearing portion 20a is inserted into the first support portion 42c of the second fixing member 42. At this time, air and residues such as lubricant oil and grease in the first concave portion 42d are discharged from the first concave portion 42d through the hollow portion 18e of the rotating shaft 18 d. Therefore, it is possible to suppress the air and the residue such as the lubricant oil and grease from being compressed in the first concave portion 42d, and to eliminate the insertion resistance of the rotary shaft 18d due to the compression of the air and the residue such as the lubricant oil and grease in the first concave portion 42d, thereby enabling the planetary gear 18b to be assembled.

Next, the second bearing portion 20b is inserted into the rotary shaft 18d, and the planetary gear 18b is attached to the third fixing member 43. At this time, air and residues such as lubricant oil and grease in the first concave portion 43h are discharged from the hole 43g formed in the bottom portion 43f of the second support portion 43 e. Therefore, it is possible to suppress the air and the residue such as the lubricant oil and grease from being compressed in the first concave portion 43h, and it is possible to eliminate the insertion resistance of the rotary shaft 18d due to the air and the residue such as the lubricant oil and grease in the first concave portion 43h being compressed, and to assemble the planetary gear 18 b.

In the wheel module not adopting the present embodiment, for example, a housing for housing the driving portion, an internal gear, and the like are fixed by bolts and are mounted to the equipment using mounting holes provided in the housing.

However, in the wheel module not adopting the present embodiment, the housing must be changed depending on the equipment to which the wheel module is mounted, and there is still room for improvement regarding the versatility of the wheel module.

On the other hand, the wheel module 200 is fixed to the stage 110 with the support member 41b extending from the first fixing member 41 sandwiched therebetween by the connection member 210. Thus, for example, when the size of the stage 110 and the method of attaching the wheel module to the stage 110 are different, the wheel module 200 can be attached to the stage 110 by changing the connection members 210 without changing the wheel portions 220 of the wheel module 200, and the versatility of the wheel module 200 can be improved.

The wheel module 200 accommodates the brake portion 13 in the support member 41b sandwiched by the connection members 210. This enables the wheel module 200 to be downsized. Further, the wheel module 200 can be attached to the stage 110 by sandwiching the support member 41b accommodating the brake portion 13 with the connection member 210, and thus the assembling property can be improved.

The wheel module 200 has a thick wall portion 41d at a portion sandwiched by the connection members 210. This can increase the strength of the support member 41b held by the connection member 210, and can suppress deformation of the support member 41 b. Therefore, the wheel module 200 can be fixed to the stage 110.

The wheel module 200 sandwiches the support member 41b between the first holding portion 3 and the second holding portion 4. This makes it possible to easily attach the wheel module 200 to the stage 110, and thus to improve the ease of assembly.

The wheel module 200 holds a power supply line 221 for supplying electric power to the drive unit 12 via the connection member 210. This can prevent the power supply line 221 from coming into contact with the tire 10 or the wheel 11.

The wheel module 200 is partitioned by the second fixing member 42 into a first housing portion 44 that houses the driving portion 12 and a second housing portion 45 that houses the planetary gear mechanism 18. Further, a hollow portion 18e is formed in the axial direction in the rotating shaft 18d of the planetary gear 18 b. The second fixed member 42 is provided with a first support portion 42c having a bottom, and the first support portion 42c supports the rotary shaft 18d of the planetary gear 18b and closes the bottom 42 g. Further, a hole 43g communicating with the hollow portion 18e is formed in the third fixing member 43 forming the second receiving portion 45 facing the first fixing member 41.

This can prevent the lubricant oil or grease from flowing out from the second housing portion 45 to the first housing portion 44, and can delay the occurrence of lubricant oil cutoff in the planetary gear mechanism 18. Therefore, the initial transmission efficiency of the power in the planetary gear mechanism 18 can be maintained for a longer time. In addition, noise generation in the planetary gear mechanism 18 can be suppressed.

In addition, in the wheel module having no cavity portion 18e and no hole 43g, air existing between the second fixed member and the planetary gear, specifically, in the first recess portion of the second fixed member may become resistance, and thus assembling of the wheel module may become difficult.

In contrast, since the wheel module 200 has the hollow portion 18e and the hole 43g, when the planetary gear 18b is assembled, it is possible to suppress the air and the residue such as the lubricating oil and grease from being compressed in the first concave portion 42d of the second fixing member 42, and to easily insert the rotary shaft 18d into the first support portion 42 c. Further, the air and the residue such as the lubricant oil and grease can be suppressed from being compressed in the first recess 43h of the third fixing member 43, and the rotary shaft 18d can be easily attached to the second support portion 43 e. Therefore, the assembling property of the wheel module 200 can be improved.

A hole 43g is formed in the bottom 43f of the second support portion 43 e. Thus, when the planetary gear 18b is assembled, air and residues such as lubricating oil and grease can be discharged from the hole 43g of the bottom portion 43f facing the rotary shaft 18 d. Therefore, the air and the residue such as the lubricant oil and grease can be suppressed from being compressed in the first recess 43h of the third fixing member 43, and the rotary shaft 18d can be easily attached to the second support portion 43 e. Therefore, the assembling property of the wheel module 200 can be improved.

The wheel module 200 closes the hole 43g with the bearing 62. This can prevent the lubricant oil or grease from flowing out of the second housing portion 45 through the hole 43 g. This can suppress oil cut in the planetary gear mechanism 18, and improve the power transmission efficiency in the planetary gear mechanism 18. In addition, noise generation in the planetary gear mechanism 18 can be suppressed.

The wheel module 200 rotatably supports the rotating shaft 18d of the planetary gear 18b via the bearing

portions

20a and 20b as the oil-impregnated sintered bearings by the second fixing member 42 and the third fixing member 43. This reduces the number of components and reduces the size of the planetary gear mechanism 18. That is, the wheel module 200 can be miniaturized.

The first fixing member 41 is formed with a supply hole 31c for supplying the lubricating oil or grease from the outside to the second housing portion 45, and a discharge hole 31d for discharging the air present in the second housing portion 45 and the degraded lubricating oil or grease to the outside when the lubricating oil or grease is supplied to the second housing portion 45. This makes it possible to easily discharge the air existing in the second housing portion 45 to the outside, and to easily supply the lubricating oil or grease to the second housing portion 45.

The wheel module 200 has a bolt 34 capable of opening and closing the discharge hole 31 d. This makes it possible to easily open and close the discharge hole 31 d.

The supply hole 31c and the discharge hole 31d are formed in the bottom 31a of the first rotating member 31. That is, the supply hole 31c and the discharge hole 31d are formed on the same surface. Therefore, the opening and closing of the discharge hole 31d and the supply of the lubricating oil/grease can be performed by the bolt 34 from the near side, and the work at the time of supplying the lubricating oil/grease can be easily performed.

The wheel module 200 rotatably supports the rotation shaft 18d of the planetary gear 18b via the bearing

portions

20a and 20b, and for example, an O-ring 50 as an elastic member is provided in a gap formed between the outer peripheral wall 20a1 of the first bearing portion 20a and the inner peripheral wall 42e1 forming the second recess 42e of the second fixed member 42. The O-ring 50 abuts against the outer peripheral wall 20a1 of the first bearing portion 20a and the inner peripheral wall 42e1 of the second fixing member 42.

Thus, the O-ring 50 absorbs the vibration generated by the meshing of the planetary gear 18b with the sun gear 18a and the ring gear 18c, and the vibration can be suppressed from being transmitted to other components such as the housing 19. Therefore, noise can be reduced. Further, dimensional errors of the planetary gear mechanism 18 can be absorbed by the O-ring 50, and the planetary gear mechanism 18 can be easily assembled. Further, dimensional errors of the planetary gear mechanism 18 can be absorbed by the O-ring 50, and the allowable value of dimensional accuracy of each member constituting the planetary gear mechanism 18 can be increased, so that the manufacturing of each member, that is, the manufacturing of the planetary gear mechanism 18 can be easily performed. Further, the use of the O-

rings

50 and 51 can improve versatility.

The wheel module 200 accommodates the O-

rings

50 and 51 in the

second recesses

42e and 43 i. This can improve the ease of assembly of the planetary gear mechanism 18.

The wheel module 200 includes, for example, a rotation preventing portion 20c that prevents rotation relative to the second fixing member 42 in the first bearing portion 20 a. This prevents the first bearing portion 20a from rotating relative to the second fixing member 42.

As shown in fig. 11, in the wheel module 200 according to the modification, the support member 41b may be inserted into an arc-shaped clamping hole 212 having a notch 211, and the support member 41b may be clamped by fastening a connecting member 210 as the clamping support member 41b with a screw 213 or the like. Fig. 11 is a perspective view of a wheel module 200 according to a modification. The portion to be fastened by the screw 213 or the like is preferably a plurality of portions, for example, two portions, at least one of which is a portion where the wall thickness portion 41d (see fig. 5) is formed. Further, the portion fastened by the screw 213 or the like may be one portion. Thus, the wheel module 200 can be fixed to the stage 110 (see fig. 1) by sandwiching the support member 41b with a simple structure of the connection member 210.

As shown in fig. 12, the wheel module 200 according to the modification may be configured such that, for example, a recess 20e is formed in the outer peripheral wall 20b1 of the second bearing portion 20b, and the O-ring 51 is accommodated in the recess 20 e. Fig. 12 is an enlarged cross-sectional view of the vicinity of the second bearing portion 20b of the wheel module 200 according to the modification. The recess 20e is formed over the entire circumference of the outer peripheral wall 20b1 of the second bearing portion 20 b. The recess 20e for accommodating the O-ring 51 may be formed in the third fixing member 43, the second bearing portion 20b, and the third fixing member 43, for example. The recess 20e may be formed in the first bearing portion 20 a.

In the wheel module 200 according to the modified example, for example, the support member 41b may be formed in a substantially D-shape in cross section by cutting the support member 41b on a plane perpendicular to the axial direction, and the first clamping portion 3a and the second clamping portion 4a may be formed in a substantially D-shape so as to match the support member 41 b. This allows the mounting position of wheel unit 220 to coupling member 210 to be matched with a predetermined position, thereby improving the ease of assembly.

In the wheel module 200 according to the modified example, a member such as the brake section 13 may be fixed by a screw from the outer peripheral side of the support member 41b, for example, from the side. Even in such a case, the wheel module 200 according to the modification can clamp the support member 41b while avoiding contact between the support member 41b and the screw by sandwiching the support member 41b from the vertical direction by the first holding portion 3 and the second holding portion 4.

In the above embodiment, the planetary gear mechanism is described as the gear mechanism, but the present invention is not limited to the planetary gear mechanism, and similar effects can be obtained as long as the gear mechanism transmits rotational force while meshing gears. In particular, in the case of using the planetary gear mechanism, since the number of gears meshing with one gear is large, it is easy to obtain an effect of further reducing the propagation of the vibration.

In the above embodiment, the O-

rings

50 and 51 are used as the elastic members, but a resin, a rubber, or the like having a smaller elastic modulus than a metal may be used as the elastic members. Further, the elastic member may have a sealing function. When the O-

rings

50 and 51 are used as the elastic members, the sealing property of the lubricating oil or grease, and the prevention of water or the like from flowing into the gear mechanism from the outside become possible as the sealing members of the gear mechanism.

As shown in fig. 13, the wheel module 200 according to the modified example may be configured without the O-rings 50 and 51 (see fig. 8) of the above-described embodiment between the first bearing portion 20a and the second fixing member 42 and between the second bearing portion 20b and the third fixing member 43. Fig. 13 is an enlarged cross-sectional view of the vicinity of the second bearing portion 20b of the wheel module 200 according to the modification.

The present invention is not limited to the above embodiments. The present invention also includes a structure configured by appropriately combining the above-described respective components. Further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspects of the present invention are not limited to the above embodiments, and various modifications are possible.

Description of the reference numerals

3 … a first holding portion; 4 … second holding part; 10 … tire; 11 … a wheel body; 12 … a drive part; 13 … brake part; 18 … planetary gear mechanism; 18b … planetary gear; 18d … rotating shaft; 18e … hollow part; 19 … a housing; 20a … first bearing portion; 20b … second bearing portion; 20c … rotation prevention part; 30 … rotating part; 31c … supply hole; 31d … outlet hole; 33 … grease nipple; 34 … bolt; 40 … securing element; 41b … support member; 41d … thickness; 42 … second fixed part; 42c … first support; 42e … second recess; 43 … third fixing element; 43e … second support portion; 43f … bottom; 43g … hole; 43i … second recess; 44 … a first receiving portion; 45 … a second receiving part; 50 … O-ring; 51 … O-ring; 62 … bearing; 100 … trolley; 110 … stage; 200 … wheel module; 210 … connecting members; 220 … wheel part.

Claims

1. A wheel module is provided with:

a gear mechanism for reducing the rotation speed of the motor;

a bearing portion into which a rotating shaft of the gear mechanism is inserted;

a support portion that supports the bearing portion; and

and an elastic member disposed in a gap formed between an outer wall of the bearing portion and an inner wall of the support portion, and abutting against the outer wall of the bearing portion and the inner wall of the support portion.

2. The wheel module of claim 1,

at least one of the support portion and the bearing portion includes a recess in which the elastic member is disposed.

3. The wheel module according to claim 1 or 2,

the bearing portion includes a rotation preventing portion that prevents rotation relative to the support portion.

4. The wheel module according to any one of claims 1 to 3,

the elastic component is an O-shaped ring.

5. The wheel module according to any one of claims 1 to 4,

the gear mechanism is a planetary gear mechanism.

6. The wheel module according to any one of claims 1 to 5,

the wheel module is provided with:

a first wall portion defining a first housing portion in which the motor portion is housed and a second housing portion in which the gear mechanism is housed; and

a second wall portion provided opposite to the first wall portion and forming the second housing portion,

a rotating shaft of a gear of the gear mechanism is provided with a hollow part formed along an axial direction of the rotating shaft,

the first wall portion includes a first support portion having a bottom and supporting the rotary shaft and having a closed bottom,

the second wall portion has a hole communicating with the hollow portion.

7. The wheel module of claim 6,

the second wall portion includes a second support portion having a bottomed shape, which supports the rotary shaft and in which the hole is formed.

8. The wheel module of claim 6 or 7,

the gear mechanism is a planetary gear mechanism,

the wheel module is provided with:

a rotating member provided outside the second wall portion and rotating together with an internal gear of the planetary gear mechanism; and

a rotary bearing portion rotatably supporting the rotary member and closing the hole.

9. The wheel module according to any one of claims 6 to 8,

the rotating shaft is supported by the first support portion and the second support portion via a sintered oil-impregnated bearing.

10. The wheel module according to any one of claims 6 to 9,

the wheel module includes a rotating member that is provided on the outer side of the second wall portion and rotates together with the gear of the gear mechanism,

the rotating member includes:

a supply unit configured to supply oil to the second storage unit from outside; and

and a discharge unit configured to discharge air existing in the second housing unit to the outside when the oil is supplied to the second housing unit.

11. The wheel module of claim 10,

the wheel module includes an opening/closing unit that opens/closes the discharge unit.

12. The wheel module of claim 10 or 11,

the rotating member includes the supply portion and the discharge portion on the same surface.

13. The wheel module according to any one of claims 1 to 12, comprising:

the wheel body is used for mounting the tire;

a driving unit provided in the wheel body to rotate the wheel body; and

and a support member extending from the fixed-side member of the drive section and fixed to the body by being sandwiched therebetween.

14. The wheel module of claim 13,

the support member accommodates a braking portion that generates braking force.

15. The wheel module of claim 14,

the support member includes a thicker portion at a portion thereof to be sandwiched than a portion thereof in which the stopper portion is accommodated.

16. The wheel module of any one of claims 13 to 15,

the wheel module includes a connecting member that sandwiches the support member and fixes the support member to the machine body.

17. The wheel module of claim 16,

the connecting member holds the support member by a plurality of members.

18. The wheel module of claim 16 or 17,

the connection member includes a power supply line holding portion that holds a power supply line that supplies electric power to the drive portion.

19. A moving mechanism, wherein,

the moving mechanism includes the wheel module according to any one of claims 1 to 18.