JP2017212860A - Electric motor and electric motor with speed reducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric motor which can inhibit a seal device from having a high temperature.SOLUTION: An electric motor includes: a rotor 20 having a shaft 21 which rotates around an axis O; a casing 30 having a penetration part 41 through which the shaft 21 penetrates in an axis O direction; a second seal member 80 fixed to a wall surface 42 of the penetration part 41, extending toward the shaft 21, and having a slide part 87 which contacts with the shaft 21; and a third seal member 90 which is provided at one side of the second seal member 80 in the axis O direction between the wall surface 42 of the penetration part 41 and an outer peripheral surface of the shaft 21 so as to be spaced away from the second seal member 80. The casing 30 has: a cooling oil supply passage 50 which supplies a cooling oil to an area between the second seal member 80 and the third seal member 90; and an upper discharge passage 51 which discharges the cooling oil from the area between the second seal member 80 and the third seal member 90.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an electric motor and an electric motor with a reduction gear.

  Patent Document 1 discloses an electric motor used in a construction machine such as a wheel loader. Cooling oil for cooling the rotor and the stator is supplied from the outside into the casing of the electric motor. A seal device for sealing the cooling oil in the casing is provided at a portion of the casing through which the shaft of the rotor passes. A part of the cooling oil supplied into the casing is supplied to the sealing device.

JP 2013-192361 A

When the motor is rotated at a high speed or when the motor is used for a long time, the cooling with the cooling oil is not sufficient, and the sealing device may become hot.
This invention is made | formed in view of such a subject, Comprising: It aims at providing the electric motor which can suppress the high temperature of a sealing device, and the electric motor with a reduction gear provided with the same.

  An electric motor according to a first aspect of the present invention includes a shaft that rotates around an axis, a rotor having a rotor core that is fixed radially outward of the shaft, a stator that surrounds the rotor core from an outer peripheral side, the rotor core, The casing is housed, and the shaft is fixed to one of a casing having a penetrating portion through which the shaft penetrates in the axial direction, a wall surface of the penetrating portion facing each other, and an outer peripheral surface of the shaft. A seal member having a sliding portion that extends and contacts the other side in the circumferential direction, and the seal on one side in the axial direction of the seal member between the wall surface of the penetrating portion and the outer peripheral surface of the shaft An annular member provided at a distance from the member and extending over the circumferential direction, and the casing and the shaft Cooling in which at least one has a cooling oil supply passage for supplying cooling oil between the seal member and the annular member, and the casing discharges the cooling oil from between the seal member and the annular member. Has an oil drain.

  An electric motor according to a second aspect of the present invention includes a shaft that rotates about an axis extending in the horizontal direction, a rotor having a rotor core that is fixed radially outward of the shaft, and a stator that surrounds the rotor core from the outer peripheral side. A casing that houses the rotor core and the stator and has a penetrating portion through which the shaft penetrates from one side in the axial direction toward the other side, the penetrating portion facing the outer peripheral surface of the shaft The axial line of the annular groove on the inner peripheral surface of the wall surface includes a wall surface including an inner peripheral surface extending in the axial direction and an annular groove recessed in the radial direction from the inner peripheral surface and extending in the circumferential direction. A seal member that is fixed to the other side of the shaft and extends in the circumferential direction of the shaft and has a sliding portion that contacts the outer circumferential surface of the shaft in the circumferential direction; An annular member provided on one side in the axial direction of the annular groove between the wall surface of the penetrating portion and the outer peripheral surface of the shaft, and provided between the seal member and the annular member, extending in the circumferential direction. Then, the space between the seal member and the annular member is partitioned into an inner space with which the sliding portion contacts and an outer space on the radially outer side of the inner space, and these inner space and outer space. A ring member having a plurality of communication holes arranged at intervals in the circumferential direction so as to communicate with each other, wherein the casing communicates with the outer space, and the seal member and the annular member And a space between the seal member and the annular member formed between the cooling oil supply passage for supplying the cooling oil and the circumferential position different from the cooling oil supply passage above the sliding portion. , Having a cooling oil discharge passage including an upper discharge passage for communicating the the space of the axial one side of the annular member.

  A reduction gear motor according to a third aspect of the present invention includes the above-described electric motor, a gear portion connected to a portion of the shaft on the other side in the axial direction with respect to the seal member, and a reduction gear casing that houses the gear portion. And a reduction gear having an output shaft that is rotatably supported by the reduction gear casing and to which the rotation of the shaft is transmitted by the gear portion, wherein at least one of the casing and the reduction gear casing is A lubricating oil supply path for supplying lubricating oil to the gear portion is provided.

  According to at least one aspect of the above aspects, it is possible to suppress an increase in the temperature of the sealing device.

It is a side view of the construction machine provided with the reduction gear with an electric motor which concerns on 1st embodiment of this invention. It is a typical top view of the drive device of the construction machine provided with the reduction gear with an electric motor which concerns on 1st embodiment of this invention. It is a longitudinal cross-sectional view of the reduction gear with an electric motor which concerns on 1st embodiment of this invention. It is an enlarged view of the vicinity of the sealing device in the longitudinal sectional view of the reduction gear with electric motor according to the first embodiment of the present invention. It is VV sectional drawing of FIG. It is an enlarged view of the vicinity of the sealing device in the longitudinal sectional view of the electric motor according to the second embodiment of the present invention. It is sectional drawing orthogonal to the axis line vicinity of the sealing device of the electric motor which concerns on 3rd embodiment of this invention. It is an enlarged view of the vicinity of the sealing device in the longitudinal sectional view of the electric motor according to the fourth embodiment of the present invention. It is sectional drawing orthogonal to the axis line vicinity of the sealing device of the electric motor which concerns on 5th embodiment of this invention.

<First embodiment>
Hereinafter, an electric motor 1 with a reduction gear according to a first embodiment of the present invention and a construction machine including the electric motor 1 with a reduction gear will be described in detail with reference to FIGS.

<Construction machinery>
As shown in FIGS. 1 and 2, the wheel loader 200 as a construction machine includes a vehicle body 210, a work machine 220, and a drive device 230.
The vehicle body 210 includes a vehicle body main body 211 that accommodates a part of the driving device 230, and a cab 212 that is provided so as to protrude upward from the vehicle body main body 211 and on which the operator's driver's seat is disposed.
The work machine 220 includes a lift arm 221 and a bucket 223. The lift arm 221 is attached to the vehicle body 210 so as to extend further forward from the front portion of the vehicle body 210. The bucket 223 is attached to the tip of the lift arm 221.

  The driving device 230 is provided integrally with the vehicle body 210 so as to support the vehicle body 210 from below. The drive device 230 includes an engine 231, an electric motor 1 with a reduction gear, a transmission 232, a pair of propeller shafts 233A and 233B, a pair of differential gears 234A and 234B, a pair of drive shafts 235A and 235B, a pair of front wheels 236 and 236, and a pair. Rear wheels 237 and 237 are provided.

  The engine 231 is housed behind the cab 212 in the vehicle body 211. For example, a diesel engine or a gasoline engine is used as the engine 231. The speed reducer-equipped electric motor 1 is provided in the vehicle body 211 so as to be adjacent to the engine 231. An axis O serving as the rotation center of the motor 1 with speed reducer extends in the horizontal direction along the width direction of the vehicle body 210. That is, the motor 1 with a speed reducer is provided in a so-called horizontal posture. The engine 231 and the motor 1 with speed reducer are power generation sources for the wheel loader 200, respectively. That is, the driving device 230 of the wheel loader 200 is a hybrid system.

Outputs of the engine 231 and the reduction gear motor 1 are input to the transmission 232. The transmission 232 synthesizes and outputs the outputs of the engine 231 and the reduction gear-equipped motor 1.
One of the pair of propeller shafts 233A and 233B is provided so as to extend forward from the transmission 232, and the other is provided so as to extend rearward from the transmission 232. These propeller shafts 233A and 233B are driven by a transmission 232, respectively.
The pair of differential gears 234A and 234B are provided at the ends of the propeller shafts 233A and 233B opposite to the transmission device 232, respectively. The differential gears 234A and 234B convert the rotation around the axis along the longitudinal direction of the vehicle body 210 by the propeller shafts 233A and 233B into rotation around the axis of the vehicle body 210 in the width direction.

The pair of drive shafts 235A and 235B are connected to differential gears 234A and 234B, respectively. The drive shafts 235 </ b> A and 235 </ b> B extend in the width direction of the vehicle body 210. The drive shafts 235A and 235B are rotated about the axis along the width direction of the vehicle body 210 when the rotation of the propeller shafts 233A and 233B is transmitted by the differential gears 234A and 234B.
The pair of front wheels 236 and 236 are fixed to both ends of the drive shaft 235A on the front side. The pair of rear wheels 237 and 237 are fixed to both ends of the rear drive shaft 235B. The wheel loader 200 travels as the front wheels 236 and 236 and the rear wheels 237 and 237 rotate.

<Electric motor with reduction gear>
As shown in FIG. 3, the motor 1 with a speed reducer includes an electric motor 10 and a speed reducer 110, and the driving force generated by the motor 10 is reduced in rotational speed by the speed reducer 110 so that the motor 1 with speed reducer 1 Is output to the transmission 232.

<Electric motor>
The electric motor 10 includes a rotor 20, a stator 190, a casing 30, a bearing device 56, a seal device 60, and a cooling oil supply unit 100.
<Rotor>
The rotor 20 includes a shaft 21, a rotor core 27, a first end plate 28a, and a second end plate 28b. Hereinafter, the radial direction of the shaft 21 is simply referred to as “radial direction”, and the circumferential direction of the shaft 21 is simply referred to as “circumferential direction”.

  The shaft 21 includes a shaft main body 22 and a sleeve 24. The shaft body 22 is a rod-like member extending along the axis O along the horizontal direction. A part of the outer peripheral surface of the shaft body 22 in the direction of the axis O is a fixed outer peripheral surface 22a to which the rotor core 27 is fixed. A shaft center hole 23 is formed in the shaft main body 22 so as to extend from the end of the shaft main body 22 on one side in the axis O direction (right side in FIG. 3) toward the other side in the axis O direction (left side in FIG. 3). .

  As shown in FIG. 4, the sleeve 24 includes a sleeve main body 25 that has a cylindrical shape centered on the axis O, and a flange portion that projects annularly outward from the one end of the sleeve main body 25 in the axis O direction. 26. The sleeve body 25 is externally fitted to the shaft body 22 at a position away from the fixed outer peripheral surface 22a of the shaft body 22 to the other side in the axis O direction.

As shown in FIG. 3, the outer shape of the rotor core 27 has a cylindrical shape, and is externally fitted to the fixed outer peripheral surface 22 a of the shaft 21. The rotor core 27 is configured by laminating a plurality of electromagnetic steel plates in the axis O direction. A plurality of long permanent magnets (not shown) extending in the direction of the axis O are embedded in the rotor core 27 at intervals in the circumferential direction. A plurality of permanent magnets may be fixed to the outer peripheral surface of the rotor core 27 at intervals.
The first end plate 28a is a disk-shaped member centered on the axis O, and is externally fitted to the shaft body 22 so as to be stacked on the rotor core 27 from one side in the axis O direction.
The second end plate 28b is a disk-shaped member centered on the axis O, and is externally fitted to the shaft body 22 so as to be stacked on the rotor core 27 from the other side in the axis O direction.

In such a rotor 20, a first cooling channel 29 a and a second cooling channel 29 b that are branched from the shaft center hole 23 and cool the rotor core 27 are formed.
The first cooling flow passage 29a extends radially outward from the end on the other side of the shaft center hole 23 in the axis O direction, and then extends between the shaft body 22 and the rotor core 27 toward the one side in the axis O direction. Yes. The first cooling flow path 29a further extends radially outward between the first end plate 28a and the rotor core 27, and then extends in the rotor core 27 toward the other side in the axis O direction so as to extend along the axis O of the second end plate 28b. It opens on the surface facing the other side.
The second cooling passage 29b extends radially outward from the other end of the shaft center hole 23 in the axis O direction, and then extends between the shaft body 22 and the rotor core 27 toward the other side in the axis O direction. Yes. The second cooling flow path 29b further extends radially outward between the second end plate 28b and the rotor core 27, and then extends in the rotor core 27 toward one side in the axis O direction so as to extend along the axis O of the first end plate 28a. It opens on the surface facing one direction.

<Stator>
The stator 190 includes a stator core 191 and a coil 192.
The stator core 191 has a cylindrical shape centered on the axis O and a yoke 191a provided so as to surround the rotor core 27 from the radially outer side, and protrudes radially inward from the inner peripheral surface of the yoke 191a. And a plurality of teeth 191b formed at intervals in the circumferential direction. Teeth 191b is disposed such that the radially inner end thereof is spaced from the rotor core 27 in the radial direction. The stator core 191 is configured by laminating a plurality of electromagnetic steel plates in the axis O direction.
A plurality of coils 192 are provided so as to correspond to each tooth 191b, and are wound around each tooth 191b. Thus, a plurality of coils 192 are provided at intervals in the circumferential direction.

<Casing>
The casing 30 is a member that forms the outer shape of the electric motor 10. The casing 30 has a cylindrical shape extending in the direction of the axis O, and a cylindrical portion 31 whose inside is the accommodation space R1 that accommodates the rotor core 27 and the stator 190, and a first that closes the accommodation space R1 from one side in the axis O direction. The lid 34 and the second lid 40 that closes the accommodation space R1 from the other side in the axis O direction are provided.

The outer peripheral surface of the stator core 191 in the stator 190 is fixed to the inner peripheral surface of the cylindrical portion 31.
Cooling oil is introduced into the upper wall portion of the cylindrical portion 31 from the upper portion of the outer peripheral surface of the cylindrical portion 31 upward and downward from the upper portion of the inner peripheral surface of the cylindrical portion 31. A path 32 is formed. Openings on the inner peripheral surface of the cylindrical portion 31 in the cooling oil introduction path 32 are formed at two locations spaced in the axis O direction so as to sandwich the stator core 191 from the axis O direction.
In the lower wall portion of the cylindrical portion 31, a cooling oil is opened that opens downward from the lower portion of the outer peripheral surface of the cylindrical portion 31 and opens upward from the lower portion of the inner peripheral surface of the cylindrical portion 31. A path 33 is formed. Openings in the inner peripheral surface of the cylindrical portion 31 in the cooling oil lead-out path 33 are formed at two locations spaced in the axis O direction so as to sandwich the stator core 191 from the axis O direction.

In the center of the first lid portion 34, a shaft housing portion 35 that protrudes toward one side in the axis O direction is formed. A cooling oil introduction hole 36 as a flow path that penetrates the shaft housing part 35 along the axis O is formed at one end of the shaft housing part 35 in the direction of the axis O. A portion of one side of the shaft main body 22 in the axis O direction is accommodated in the shaft accommodating portion 35.
An end bearing 37 having an annular shape centering on the axis O is disposed on the inner peripheral surface of the shaft accommodating portion 35 and the outer peripheral surface of the shaft main body 22 facing each other, and one end side in the axis O direction from the end bearing 37. The end seal 38 is fixed. The end bearing 37 supports a portion of the shaft main body 22 on one side in the axis O direction so as to be rotatable relative to the shaft accommodating portion 35 around the axis O. The end seal 38 ensures the liquid tightness at the place where the end seal 38 is installed.

The second lid portion 40 has a disk shape extending about the axis O in the direction orthogonal to the axis O. The first surface 40 a facing the one side in the axis O direction of the second lid portion 40 is fixed in contact with the surface facing the other side of the cylindrical portion 31 in the axis O direction.
The second lid part 40 is formed with a penetration part 41, a cooling oil supply path 50, an upper discharge path (cooling oil discharge path) 51, a lubricating oil supply path 52, and a gas reservoir 54.
<Penetration part>

  The penetrating portion 41 is a hole formed over the first surface 40a of the second lid portion 40 and the second surface 40b located on the opposite side of the first surface 40a and facing the other side in the axis O direction. The penetrating part 41 extends around the axis O so as to penetrate the second lid part 40 in the direction of the axis O. The wall surface 42 of the penetrating portion 41, that is, the wall surface 42 forming the penetrating portion 41 faces the outer peripheral surface of the shaft 21 in the radial direction. The shaft 21 penetrates the penetrating part 41 in the axis O direction, so that the end on the other side in the axis O direction protrudes outside the casing 30.

As shown in FIG. 4, the wall surface 42 of the penetrating portion 41 includes a bearing fixing surface 43, a first step surface 44, a first inner peripheral surface 45, a second step surface 46, and a second inner peripheral surface (inner peripheral surface) 47. And an annular groove 48.
The bearing fixing surface 43 is formed in the most part of the penetrating portion 41 on the one side in the axis O direction, and has a cylindrical surface shape that faces inward in the radial direction and extends in the axis O direction around the axis O. One end of the bearing fixing surface 43 on the one side in the direction of the axis O opens into the accommodation space R1 and is connected so as to be orthogonal to the first surface 40a. The bearing fixing surface 43 faces the outer peripheral surface of the shaft body 22 in the shaft 21 in the radial direction.

The first step surface 44 extends radially inward from the end of the bearing fixing surface 43 on the other side in the axis O direction. The first step surface 44 is an annular surface centered on the axis O and faces one side in the axis O direction.
The first inner peripheral surface 45 extends from the radially inner end of the first step surface 44 toward the other side in the axis O direction. The first inner peripheral surface 45 has a cylindrical surface shape that faces inward in the radial direction and extends in the axis O direction with the axis O as the center. The first inner peripheral surface 45 faces the flange portion 26 of the sleeve 24 in the shaft 21 in the radial direction.

The second step surface 46 extends further radially inward from the other end of the first inner peripheral surface 45 in the axis O direction. The second step surface 46 is an annular surface centered on the axis O and faces one side in the axis O direction.
The second inner peripheral surface 47 extends from the radially inner end of the second step surface 46 toward the other side in the axis O direction. The second inner peripheral surface 47 has a cylindrical surface shape that faces inward in the radial direction and extends in the axis O direction around the axis O. The second inner peripheral surface 47 faces the sleeve body 25 of the sleeve 24 in the shaft 21 in the radial direction. The end of the second inner peripheral surface 47 on the other side in the axis O direction is open to the other side of the second lid 40 in the axis O direction, and the second inner peripheral surface 47 is orthogonal to the second surface 40b. It is connected.

The annular groove 48 is provided in the range of the second inner peripheral surface 47 in the axis O direction. The annular groove 48 is opposed to the sleeve body 25 in the sleeve 24 of the shaft 21 in the radial direction. The annular groove 48 is formed such that a part of the second inner peripheral surface 47 in the direction of the axis O is recessed radially outward. The annular groove 48 has an annular shape extending around the entire region in the circumferential direction about the axis O.
The annular groove 48 has a bottom surface 48a, a first inner side surface 48b, and a second inner side surface 48c. The bottom surface 48a is a surface constituting the bottom of the annular groove 48, and has a cylindrical surface shape that faces inward in the radial direction and extends in the direction of the axis O about the axis O. The first inner side surface 48 b extends across the end of the bottom surface 48 a on one side in the axis O direction and the second inner peripheral surface 47. The first inner surface 48b is an annular surface centered on the axis O and faces the other side in the axis O direction. The second inner side surface 48 c extends across the end of the bottom surface 48 a on the other side in the axis O direction and the second inner peripheral surface 47. The second inner side surface 48c is an annular surface centered on the axis O and faces one side in the axis O direction. The first inner side surface 48b and the second inner side surface 48c face each other in the direction of the axis O.

<Cooling oil supply path>
As shown in FIG. 3, the cooling oil supply path 50 is a flow path formed in the second lid portion 40 of the casing 30, one end opening on the outer peripheral surface of the second lid portion 40, and the other end. An opening is formed in the annular groove 48 of the wall surface 42 of the penetrating portion 41. The cooling oil supply path 50 allows the outside of the casing 30 to communicate with the inside of the annular groove 48. The cooling oil supply path 50 extends linearly from the outer peripheral surface of the second lid 40 inward in the radial direction.
As shown in FIG. 4, the radially inner end of the cooling oil supply passage 50 reaches a portion radially inward of the bottom surface 48 a of the annular groove 48 of the penetrating portion 41. The peripheral surface 47 is not reached. The cooling oil supply path 50 is formed at a position where the central axis P is shifted to the other side in the axis O direction from the annular groove 48, and only a part of the cooling oil supply path 50 overlaps the annular groove 48 from the other side in the axis O direction. The annular groove 48 communicates with each other.

  As shown in FIG. 5, the central axis P of the cooling oil supply passage 50 is one side in the circumferential direction with respect to a vertical line L going upward from the axis O of the shaft 21 in a cross-sectional view orthogonal to the axis O (FIG. 5). At a position deviated in the clockwise direction) in the radial direction. In the present embodiment, the angle θ1 formed by the central axis P of the cooling oil supply passage 50 and the vertical line L is set to 15 °. The angle θ1 is not limited to this value and may be changed as appropriate. The angle θ1 may be set, for example, in the range of 5 ° to 45 °, preferably in the range of 10 ° to 30 °, more preferably in the range of 15 ° to 20 °.

<Upper discharge path (cooling oil discharge path)>
As shown in FIG. 4, the upper discharge path 51 is a hole extending in the direction of the axis O across the first inner side surface 48 b in the annular groove 48 of the wall surface 42 of the penetration portion 41 and the second step surface 46 of the wall surface 42 of the penetration portion 41. Part. The other end of the upper discharge path 51 in the direction of the axis O is open in the annular groove 48. One end of the upper discharge path 51 in the direction of the axis O is open to a space in contact with the second step surface 46. In the present embodiment, as shown in FIG. 5, the upper discharge path 51 is formed to have an arc shape that is recessed radially outward from the second inner peripheral surface 47 of the through portion 41 in a cross-sectional view orthogonal to the axis O. ing. The upper discharge path 51 is shifted to the other side in the circumferential direction (counterclockwise direction side in FIG. 5) with respect to the vertical line L extending upward from the axis O of the shaft 21 in a cross-sectional view orthogonal to the axis O. Is formed. That is, the upper discharge path 51 is formed at a circumferential position different from the cooling oil supply path 50. These upper discharge passage 51 and cooling oil supply passage 50 do not overlap each other in the radial direction. In the present embodiment, in a cross-sectional view orthogonal to the axis O, a reference line Q that passes through the axis O and the most radially outer portion of the upper discharge path 51, that is, the center of the arc of the axis O and the upper discharge path 51, The reference line Q passing through the vertical line L forms an angle θ2. The angle θ2 is set to 15 °. The angle θ2 is not limited to this value and may be changed as appropriate. The angle θ2 may be set, for example, in the range of 5 ° to 45 °, preferably in the range of 10 ° to 30 °, and more preferably in the range of 15 ° to 20 °.

<Lubrication oil supply path>
As shown in FIG. 3, one end of the lubricating oil supply path 52 opens on the outer peripheral surface of the second lid portion 40, and the other end opens on the second surface 40 b of the second lid portion 40. The other end of the lubricating oil supply passage 52 has a plurality of openings at intervals in the circumferential direction at the same radial position on the second surface 40b.
One end of the second lid portion 40 is connected to the lubricating oil supply passage 52 and the other end opens to the second surface 40 b on the outer side in the radial direction than the opening portion of the second surface 40 b of the lubricating oil supply passage 52. A branch channel 53 is formed. A portion extending in the radial direction in the lubricating oil supply path 52 is formed along a vertical line L (not shown in FIG. 3).

<Gas reservoir>
As shown in FIG. 3, the gas reservoir 54 is a hole extending in the radial direction so as to communicate the lower portion of the outer peripheral surface of the second lid portion 40 with the through portion 41. The radially inner end of the gas reservoir 54 opens to a portion on the other side in the axis O direction with respect to the annular groove 48 in the second inner peripheral surface 47 of the wall surface 42 of the penetrating portion 41.

<Bearing device>
As shown in FIG. 3, the bearing device 56 is an annular member provided between the wall surface 42 of the penetrating portion 41 of the casing 30 and the outer peripheral surface of the shaft main body 22 in the shaft 21. As shown in FIG. 4, the outer peripheral side of the bearing device 56 is fixed to the bearing fixing surface 43 and the first step surface 44, and the inner peripheral side is fixed to the outer peripheral surface of the shaft body 22. Thus, the bearing device 56 supports the shaft 21 relative to the casing 30 so as to be relatively rotatable around the axis O on the other side of the rotor 20 in the axis O direction with respect to the rotor core 27.

<Sealing device>
As shown in FIG. 4, the sealing device 60 includes a first seal member 70, a second seal member (seal member) 80, and a third seal provided between the wall surface 42 of the penetrating portion 41 of the casing 30 and the shaft 21. A member (annular member) 90 and a ring member 105 are provided.

<First seal member, second seal member (seal member)>
The first seal member 70 and the second seal member 80 are oil seals arranged with a space in the direction of the axis O between the second inner peripheral surface 47 of the wall surface 42 of the penetrating portion 41 and the sleeve body 25. The first seal member 70 is disposed on one side of the annular groove 48 and the second seal member 80 in the axis O direction, and the second seal member 80 is disposed between the first seal member 70 and the annular groove 48. In the present embodiment, the second seal member 80 is disposed adjacent to the other side of the annular groove 48 in the axis O direction. The first seal member 70 and the second seal member 80 extend in the circumferential direction, that is, the first seal member 70 and the second seal member 80 have an annular shape surrounding the shaft 21.

  The outer peripheral surfaces of the first seal member 70 and the second seal member 80 are fixed in contact with the second inner peripheral surface 47 of the wall surface 42 of the penetrating portion 41 in the circumferential direction. The inner peripheral portions of the first seal member 70 and the second seal member 80 are lip portions 76 and 86. A part of the inner peripheral surface of the lip portions 76 and 86 is formed as sliding portions 77 and 87 that are slidably contacted with the sleeve body 25 of the shaft 21 in the circumferential direction when the shaft 21 rotates. That is, the first seal member 70 and the second seal member 80 are fixed to the wall surface 42 of the penetrating portion 41, extend toward the shaft 21 side, and the sliding portions 77 and 87 come into contact with the shaft 21. ing.

  The first seal member 70 and the second seal member 80 are arranged symmetrically with respect to a symmetry plane perpendicular to the axis O between them. The first seal member 70 mainly suppresses liquid leakage from the other side in the axis O direction in the sliding portion 77 to the one side. The second seal member 80 mainly suppresses liquid leakage from one side to the other side in the axis O direction in the sliding portion 87.

The uppermost portion of the sliding portion 87 of the second seal member 80 is located below the upper discharge path 51. That is, the upper discharge path 51 is located further above the uppermost portion of the sliding portion 87 of the second seal member 80. Note that the uppermost portion of the sliding portion 87 of the second seal member 80 is located on a vertical line L extending upward from the axis O in FIG.
The radially inner end of the gas reservoir 54 is open between the first seal member 70 and the second seal member 80 in the space between the wall surface 42 of the penetrating portion 41 and the sleeve 24 of the shaft 21.

<Third seal member (annular member)>
The third seal member 90 is a dust seal disposed on the one side in the axis O direction with respect to the annular groove 48 in the second inner peripheral surface 47 of the penetrating portion 41. The third seal member 90 is disposed on the one side in the axis O direction of the second seal member 80 with a space from the second seal member 80. The third seal member 90 is disposed with a space on one side in the axis O direction with respect to the annular groove 48. The third seal member 90 extends in the circumferential direction, that is, the third seal member 90 has an annular shape surrounding the shaft 21.

The outer peripheral surface of the third seal member 90 is fixed in contact with the second inner peripheral surface 47 of the wall surface 42 of the penetrating portion 41 in the circumferential direction. A portion on the inner peripheral side of the third seal member 90 is a lip portion 96. A part of the inner peripheral surface of the lip portion 96 is a sliding portion 97 that contacts the sleeve 24 of the shaft 21 in the circumferential direction so as to be slidable when the shaft 21 rotates. That is, the third seal member 90 is fixed to the wall surface 42 of the penetrating portion 41, extends toward the shaft 21 side, and the sliding portion 97 is in contact with the shaft 21.
The third seal member 90 suppresses a certain amount of liquid leakage from the other side in the axis O direction in the sliding portion 97 to the one side.

<Oil storage space>
An oil accommodating space S as a space between the second seal member 80 and the third seal member 90 is defined by the second seal member 80, the third seal member 90, and the wall surface 42 of the penetrating portion 41. The oil storage space S surrounds the sleeve 24 from the entire circumferential direction on the radially outer side of the sleeve 24 of the shaft 21. In the present embodiment, a radially outer portion of the oil containing space S is defined by the annular groove 48 in the wall surface 42 of the penetrating portion 41. The oil storage space S is in contact with the sleeve 24 of the shaft 21 in the entire circumferential direction. In other words, the oil storage space S is added to the second seal member 80, the third seal member 90, and the wall surface 42 of the penetration portion 41. It is defined by the shaft 21. As shown in FIG. 5, the oil storage space S has an annular shape in cross section perpendicular to the axis O.

<Ring member>
As shown in FIGS. 4 and 5, the ring member 105 is a member that is provided in the oil storage space S and has an annular shape about the axis O. As shown in FIG. 4, the portion on the one side in the axis O direction of the outer peripheral surface of the ring member 105 is fixed in contact with the second inner peripheral surface 47 of the wall surface 42 of the penetrating portion 41. Of the outer peripheral surface of the ring member 105, the portion on the other side in the axis O direction faces the inside of the annular groove 48 from the radially inner side. The inner peripheral surface of the ring member 105 is disposed at a distance from the outer peripheral surface of the sleeve body 25 of the shaft 21 in the radial direction. That is, the inner peripheral surface of the ring member 105 is opposed to the outer peripheral surface of the shaft 21 in the radial direction.

  A surface of the ring member 105 facing one side in the axis O direction is in contact with the third seal member 90. A surface of the ring member 105 facing the other side in the axis O direction is in contact with the second seal member 80. Since the ring member 105 is interposed as a spacer between the second seal portion and the third seal member 90, the interval in the axis O direction between the second seal member 80 and the third seal member 90 is maintained. .

The oil storage space S is divided into two spaces on the inner side and the outer side in the radial direction by the ring member 105. A space on the inner side in the radial direction of the ring member 105 is an inner space S1. A space on the outer side in the radial direction of the ring member 105 is an outer space S2. The inner space S <b> 1 and the outer space S <b> 2 have an annular shape that extends over the entire circumferential direction around the axis O.
In the present embodiment, the inner space S <b> 1 is defined by the second seal member 80, the third seal member 90, and the ring member 105, and is in contact with the outer peripheral surface of the sleeve 24 of the shaft 21 over the entire circumferential direction. . Therefore, the sliding portions 87 and 97 of the second seal member 80 and the third seal member 90 are in contact with the inner space S1.

  In the present embodiment, the outer space S <b> 2 is partitioned by the annular groove 48 and the ring member 105. Therefore, the cooling oil supply path 50 that communicates with the annular groove 48 communicates with the outer space S2, and similarly, the upper discharge path 51 that communicates with the annular groove 48 communicates with the outer space S2.

In the ring member 105, a plurality of communication holes 106 penetrating the ring member 105 in the radial direction are formed at intervals in the circumferential direction. In the present embodiment, a total of eight communication holes 106 are formed at equal intervals in the circumferential direction. By these communication holes 106, the inner space S1 and the outer space S2 of the oil containing space S are communicated with each other in the radial direction. As shown in FIG. 5, one of the plurality of communication holes 106 is located on a line extending radially inward of the central axis P of the cooling oil supply passage 50 in a cross section perpendicular to the axis O direction. Yes.
The upper discharge path 51 is closed from the radially inner side by the ring member 105 and the third seal member 90.

<Cooling oil supply unit>
As shown in FIG. 3, the cooling oil supply unit 100 supplies cooling oil into the casing 30. In the present embodiment, the cooling oil supplied into the casing 30 is collected, cooled, and then supplied into the casing 30 again. That is, the cooling oil is circulated by the cooling oil supply unit 100.
The cooling oil supply unit 100 includes a cooling oil circulation channel 101, a cooling oil pump 102, and a cooling oil cooling unit 103.

The cooling oil circulation passage 101 is connected to the opening of the cooling oil outlet passage 33 on the outer peripheral surface of the cylindrical portion 31 of the casing 30 at the upstream end. The cooling oil circulation passage 101 is branched into three passages on the downstream side, the cooling oil introduction hole 36 in the first lid portion 34 of the casing 30, and the cooling oil introduction passage 32 in the outer peripheral surface of the cylindrical portion 31 of the casing 30. And the cooling oil supply passage 50 on the outer peripheral surface of the second lid portion 40 of the casing 30.
The cooling oil pump 102 is provided in the cooling oil circulation passage 101, and moves the cooling oil from the upstream side to the downstream side, that is, from the outlet of the cooling oil outlet passage 33 of the casing 30 to the cooling oil introduction passage of the casing 30. Pump to 32 inlets.
The cooling oil cooling unit 103 is provided in the cooling oil circulation passage 101 and cools the cooling oil flowing through the cooling oil circulation passage 101. The cooling oil cooling unit 103 cools the cooling oil, for example, by exchanging heat between the external air and the cooling oil.

<Reduction gear>
The reduction gear 110 is provided integrally with the electric motor 10 on the other side in the axis O direction of the electric motor 10. The reduction gear 110 includes a reduction gear casing 120, a planetary gear device (gear portion) 130, an output shaft 140, and a lubricating oil supply portion 150.

<Speed reducer casing>
The reduction gear casing 120 has a cylindrical shape that opens on both sides in the direction of the axis O. One end of the reduction gear 110 in the direction of the axis O is fixed integrally to the second surface 40 b of the second lid 40 of the casing 30 of the electric motor 10. A portion on one side in the axis O direction inside the reduction gear casing 120 is a gear housing space R2. In the gear housing space R2, an end portion on the other side in the axis O direction of the shaft 21 protruding from the casing 30 of the electric motor 10 is located.
A reduction gear penetrating portion 121 that connects the gear housing space R <b> 2 and the outside of the reduction gear casing 120 in the direction of the axis O is formed on the other side of the reduction gear casing 120 in the axis O direction. A pair of speed reducer bearings 124 each having an annular shape centering on the axis O is fixed to the inner peripheral surface of the speed reducer penetrating portion 121 with an interval in the direction of the axis O.

One end of a bearing lubrication flow path 122 that communicates with the branch flow path 53 that opens on the second surface 40 b of the second lid portion 40 opens at the end face on one side in the axis O direction of the reduction gear casing 120. The other end of the bearing lubrication flow path 122 opens between the pair of speed reducer bearings 124 on the inner peripheral surface of the speed reducer penetrating portion 121.
In the lower part of the reduction gear casing 120, a lubricating oil discharge hole 123 that connects the gear housing space R2 and the space below the reduction gear casing 120 is formed.

<Planetary gear device (gear part)>
The planetary gear device 130 is provided in the gear housing space R <b> 2 of the reduction gear casing 120. The planetary gear device 130 includes a sun gear 131, a planet carrier 132, a planetary gear 134, and an internal gear 136.
The sun gear 131 is externally fitted on the outer peripheral surface of the other end portion of the shaft 21 of the electric motor 10 in the gear housing space R2 on the other side in the axis O direction, and gear teeth are formed on the outer peripheral side. The sun gear 131 is a helical gear, and the thrust force during rotation is supported by the bearing device 56 via the sleeve 24.
The planet carrier 132 is a disk-shaped member centered on the axis O, and is integrally fixed to the second surface 40 b of the second lid portion 40 of the casing 30 so as not to be relatively rotatable in the circumferential direction. The planetary carrier 132 is formed with a plurality of in-carrier channels 133 that respectively communicate with the plurality of lubricating oil supply passages 52 opened in the second surface 40 b of the second lid portion 40 of the casing 30 and penetrate in the direction of the axis O. ing.

The planetary gear 134 has gear teeth that mesh with the gear teeth of the sun gear 131, and a plurality of planet gears 134 are provided at intervals in the circumferential direction. The planetary gear 134 is supported by the planetary carrier 132 so as to be rotatable around a fixed axis parallel to the axis O. The planetary gear 134 is formed with an in-gear flow path 135 that communicates with the in-carrier flow path 133 and extends along the fixed axis and opens to the outer peripheral surface of the planetary gear 134.
The internal gear 136 is an annular member centering on the axis O, and gear teeth are formed on the inner peripheral side. The gear teeth of the internal gear 136 mesh with the gear teeth of the plurality of planetary gears 134, respectively.

The output shaft 140 is a rod-shaped member extending along the axis O. The output shaft 140 is provided so as to be relatively rotatable around the axis O with respect to the speed reducer casing 120 via a pair of speed reducer bearings 124.
A connecting portion 141 extending outward in the radial direction so as to protrude radially outward from the output shaft 140 is integrally fixed to an end of the output shaft 140 on one side in the axis O direction. The radially outer end of the connecting portion 141 is integrally fixed to the internal gear 136 of the planetary gear device 130. As a result, the internal gear 136 and the output shaft 140 rotate around the axis O in conjunction with each other.
The other end of the output shaft 140 on the other side in the direction of the axis O protruding from the reduction gear casing 120 to the outside is connected to the input portion of the transmission 232 of the construction machine.

<Lubricating oil supply unit>
The lubricating oil supply unit 150 supplies lubricating oil to the planetary gear unit 130 and the reduction gear bearing 124 in the reduction gear casing 120. In the present embodiment, the lubricating oil supplied into the reducer casing 120 is collected, cooled, and then supplied again into the reducer casing 120. That is, the lubricating oil is circulated by the lubricating oil supply unit 150.
The lubricating oil supply unit 150 includes a lubricating oil circulation channel 151, a lubricating oil pump 152, and a lubricating oil cooling unit 153.

The upstream end of the lubricating oil circulation channel 151 is connected to the lubricating oil discharge hole 123 of the reduction gear casing 120. The lubricating oil circulation channel 151 is connected at its downstream end to a lubricating oil supply channel 52 that opens to the outer peripheral surface of the casing 30 of the electric motor 10.
The lubricating oil pump 152 is provided in the lubricating oil circulation passage 151, and moves the lubricating oil from the upstream side toward the downstream side, that is, from the outlet of the lubricating oil discharge hole 123 of the reduction gear casing 120. To the inlet of the lubricating oil supply passage 52.
The lubricating oil cooling unit 153 is provided in the lubricating oil circulation channel 151 and cools the lubricating oil flowing through the lubricating oil circulation channel 151. The lubricating oil cooling unit 153 cools the lubricating oil, for example, by exchanging heat between the air from the outside and the lubricating oil.

<Operation and effect of motor with reduction gear>
When the wheel loader 200 moves forward or backward, the motor 10 of the motor 1 with speed reducer is driven together with the engine 231. When the electric motor 10 is driven, AC power is supplied to each coil 192 of the stator 190 via the inverter, and the rotor 20 rotates with respect to the stator 190 by each permanent magnet following the rotating magnetic field generated by these coils 192. To do.

When the rotor 20 rotates about the axis O, the rotation of the shaft 21 of the rotor 20 is input to the planetary gear unit 130. That is, the sun gear 131 attached to the shaft 21 rotates around the axis O along with the rotation of the shaft 21. As the sun gear 131 rotates, the plurality of planetary gears 134 rotate around the fixed axis O, and the internal gear 136 that meshes with the planetary gear 134 rotates around the axis O. At this time, the internal gear 136 rotates at a rotational speed at a gear ratio corresponding to the number of teeth of the sun gear 131, the planetary gear 134 and the internal gear 136 with respect to the rotational speed of the shaft 21. That is, the rotation of the shaft 21 is decelerated and transmitted to the internal gear 136.
When the internal gear 136 rotates, the output shaft 140 connected to the internal gear 136 via the connecting portion 141 rotates about the axis O. The rotation of the output shaft 140 is input to the transmission 232 of the wheel loader 200 as an output of the motor 1 with speed reducer.

When the electric motor 10 is driven, cooling oil is supplied into the casing 30 of the electric motor 10. When the cooling oil pump 102 of the cooling oil supply unit 100 is operated, the cooling oil is supplied to the cooling oil introduction hole 36 and the cooling oil introduction passage 32 of the casing 30 through the cooling oil circulation passage 101.
The cooling oil supplied to the cooling oil introduction hole 36 circulates through the first cooling flow path 29a and the second cooling flow path 29b via the shaft center hole 23 of the shaft 21, and cools the rotor core 27 and the permanent magnet in this process. To do. Thereafter, the cooling oil is supplied from the first end plate 28a or the second end plate 28b into the accommodation space R1. On the other hand, the cooling oil that has flowed through the cooling oil introduction path 32 is supplied into the accommodation space R <b> 1 from two locations that are separated from each other in the direction of the axis O on the inner peripheral surface of the casing 30.
The cooling oil supplied into the accommodation space R <b> 1 cools the surfaces of the stator 190 and the rotor 20 and is introduced into the cooling oil lead-out path 33 of the casing 30. The cooling oil that has flowed through the cooling oil lead-out path 33 flows through the cooling oil circulation path 101, is cooled by the cooling oil cooling unit 103, and is again pumped into the casing 30 by the cooling oil pump 102.

  Lubricating oil is introduced into the reduction gear casing 120 when the electric motor 10 is driven. When the lubricating oil pump 152 of the lubricating oil supply unit 150 is activated, the lubricating oil is supplied to the lubricating oil supply passage 52 of the casing 30 via the lubricating oil circulation passage 151. The lubricating oil flowing through the lubricating oil supply path 52 is supplied to the planetary gear device 130. That is, the lubricating oil in the lubricating oil supply path 52 is supplied to the outer surface of the planetary gear 134 via the in-carrier channel 133 and the in-gear channel 135. As a result, the lubricating oil is supplied to the meshing portions of the planetary gear 134, the sun gear 131, and the internal gear 136. A part of the lubricating oil flowing through the lubricating oil supply path 52 is supplied to the reduction gear bearing 124 via the branch flow path 53 and the bearing lubricating flow path 122. The lubricating oil again flows from the gear housing space R2 of the reduction gear casing 120 through the lubricating oil circulation passage 151 again, cooled by the lubricating oil cooling section 153, and then again lubricated by the lubricating oil pump 152. It is pumped to the oil supply path 52.

In the motor 1 with a speed reducer thus driven, the cooling oil supplied into the casing 30 of the motor 10 and the lubricating oil supplied into the speed reducer casing 120 of the speed reducer 110 are of different types. May be used. Even if the cooling oil and the lubricating oil are of the same type, the temperature and cleanliness may be different from each other. That is, in the planetary gear unit 130 of the reduction gear 110, the lubricating oil is likely to become high temperature due to frictional heat generated by the meshing of the gears, and metal powder is likely to be mixed into the lubricating oil due to wear of the gears. As a result, the lubricating oil has a higher temperature and a lower cleanliness than the cooling oil. In the present embodiment, the first seal member 70 prevents the lubricating oil from being mixed into the casing 30 of the electric motor 10.
On the other hand, if the cooling oil supplied into the casing 30 of the electric motor 10 leaks to the reduction gear 110 side, it is necessary to replenish the cooling oil of the electric motor 10 and the maintainability is deteriorated. In the present embodiment, the second seal member 80 prevents leakage of cooling oil to the speed reducer 110 side.

  Here, the construction machine such as the wheel loader 200 is continuously operated at a high load. Therefore, the sliding portions 77, 87, and 97 of the sealing device 60 are likely to become high temperature due to friction with the shaft 21. For example, it can be considered that the cooling oil is supplied to the sealing device 60 by extending the shaft center hole 23 to the other side in the axis O direction. In this case, a large amount of cooling oil may flow through the first cooling flow path 29 a and the second cooling flow path 29 b connected to the upstream side of the shaft center hole 23, and sufficient cooling oil may not be supplied to the sealing device 60. is there. Further, the supply of the cooling oil to the sealing device 60 through the shaft center hole 23 uses the centrifugal force of the shaft 21. However, since the wheel loader 200 frequently switches between forward and reverse, the centrifugal force does not act when the shaft 21 does not rotate at the time of switching, and the cooling oil is difficult to be supplied to the sealing device 60. Therefore, there is a case where blisters that expand due to the high temperature of the cooling oil that has penetrated into the lip portions 76, 86, and 96 of the sealing device 60 and deteriorate the lip portions 76, 86, and 96 are generated. Since the first seal member 70 is configured to easily come into contact with the lubricating oil of the speed reducer 110, it is necessary to suppress the high temperature particularly in the second seal member 80 and the third seal member 90.

In contrast, in the present embodiment, the cooling oil is supplied to the second seal member 80 and the third seal member 90 without passing through the shaft 21, and the second seal member 80 and the third seal member 90 are always cooled. By maintaining the oil bath state in contact with the second seal member 80, the second seal member 80 and the third seal member 90 are prevented from being heated and deteriorated.
In the present embodiment, the cooling oil is supplied into the cooling oil supply path 50 of the second lid portion 40 of the casing 30 via the cooling oil supply unit 100.

  The cooling oil flowing through the cooling oil supply path 50 is introduced into the annular groove 48 of the through portion 41 at the lower end of the cooling oil supply path 50. As shown in FIG. 5, the cooling oil introduced into the annular groove 48 accumulates from the lower part of the outer space S <b> 2 of the oil storage space S defined by the annular groove 48, and passes through the communication hole 106 of the ring member 105. The oil is introduced into the inner space S1 of the oil storage space S. In this way, the cooling oil supplied into the oil storage space S passes through the upper discharge passage 51 in the axis when the liquid level of the cooling oil in the oil storage space S reaches the vertical position of the upper discharge passage 51. Circulates on one side in the O direction. The cooling oil that has flowed through the upper discharge path 51 is discharged into a space on the one side in the axis O direction of the third seal member 90 between the wall surface 42 of the penetrating portion 41 and the shaft 21. Thereafter, the cooling oil passes between the outer ring 57 and the inner ring 58 of the bearing device 56 to lubricate the bearing device 56 and is introduced into the accommodation space R <b> 1 in the casing 30.

  As described above, in the present embodiment, the cooling oil is stored in the oil storage space S, and the oil storage space S is filled with the cooling oil up to the height of the upper discharge path 51. Therefore, the second seal member 80 and the third seal member 90 are always in contact with the cooling oil. That is, since the second seal member 80 and the third seal member 90 are in a so-called oil bath state in which they are constantly in contact with the cooling oil, the second seal member 80 and the third seal member 90 can be effectively cooled. As a result, the high temperature and deterioration of the second seal member 80 and the third seal member 90 can be suppressed.

  Since the cooling oil in the inner space S <b> 1 of the oil containing space S is in contact with the shaft 21, the cooling oil flows in the circumferential direction due to viscosity as the shaft 21 rotates. Therefore, the fluidity of the cooling oil in contact with the shaft 21 can be ensured, and only a part of the cooling oil in the circumferential direction can be prevented from locally becoming hot. Therefore, a cooling effect can be obtained appropriately.

If there is no ring member 105, the cooling oil in contact with the shaft 21 tends to flow in the circumferential direction along with the shaft 21, but due to the influence of the viscosity of the stationary cooling oil spaced radially outward from the shaft 21, The flow of the cooling oil in the vicinity of the shaft 21 is suppressed.
In contrast, in the present embodiment, the oil containing space S is partitioned by the inner space S1 and the outer space S2 by the ring member 105, and the flow passage cross-sectional area in the circumferential direction around the shaft 21 is reduced. . Thereby, the influence of the viscosity of the cooling oil that is radially separated from the shaft 21 can be reduced, and the cooling oil around the shaft 21 can be smoothly flowed in the circumferential direction.
On the other hand, since a plurality of communication holes 106 are formed in the ring member 105, the cooling oil in the inner space S1 and the outer space S2 can be circulated with each other. Therefore, heat is not excessively accumulated in the inner space S1. Therefore, the cooling effect of the second seal member 80 and the third seal member 90 that slide with respect to the shaft 21 can be further enhanced.
Since the ring member 105 of the present embodiment is a spacer in the direction of the axis O between the second seal member 80 and the third seal member 90, a large volume of the inner space S1 of the oil storage space S can be secured. .

  The oil containing space S is defined not only by the second seal member 80 and the third seal member 90 but also by the annular groove 48 of the wall surface 42 of the penetrating portion 41. Therefore, a large volume of the oil storage space S can be ensured. Thereby, compared with the case where the oil accommodation space S is defined only in the radial range of the second seal member 80 and the third seal member 90, a larger amount of cooling oil can be stored, and the cooling effect is improved. be able to.

Since the circumferential positions of the cooling oil supply path 50 and the upper discharge path 51 communicating with each other in the oil storage space S are different from each other, the cooling oil supplied from the cooling oil supply path 50 into the oil storage space S is used as it is. It is not discharged from 51. That is, the cooling oil supplied into the oil storage space S once flows in the circumferential direction and then is discharged from the oil storage space S. Therefore, it is possible to prevent the cooling oil from being discharged without contributing to the cooling of the sealing device 60.
In the present embodiment, as shown in FIG. 5, a part of the communication hole 106 of the ring member 105 is disposed on the extended line of the central axis P of the cooling oil supply passage 50. Therefore, more cooling oil can be supplied to the inner space S <b> 1 through the communication hole 106.

The upper discharge path 51 communicates with the upper part of the annular groove 48, that is, is formed above the sealing device 60. Therefore, the liquid level in the oil storage space S can be in a state where the second seal member 80 and the third seal member 90 are always immersed in the cooling oil. In particular, since the sliding portions 87 and 97 of the second seal member 80 and the third seal member 90 are always in contact with the cooling oil, the second seal member 80 and the third seal member 90 are effectively cooled. Can do.
The cooling oil discharged from the oil storage space S then cools the bearing device 56 via the bearing device 56. Therefore, an efficient cooling path can be realized in the casing 30.

<Second embodiment>
An electric motor 10A of the second embodiment will be described with reference to FIG. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The motor 10A of the second embodiment is different from the first embodiment in that the sealing device 160 includes a dam member (annular member) 161 instead of the third seal member 90 of the first embodiment.

The dam member 161 is disposed on one side in the axis O direction with respect to the annular groove 48 in the second inner peripheral surface 47 of the wall surface 42 of the penetrating portion 41. The dam member 161 has a fixed portion 162 and an overhang portion 163.
The fixed part 162 is a cylindrical member centered on the axis O. The outer peripheral surface of the fixing portion 162 is fixed to the second inner peripheral surface 47 of the wall surface 42 of the penetrating portion 41. The other end of the fixed portion 162 in the direction of the axis O is in contact with the ring member 105.

  The overhang portion 163 has a disk shape that protrudes inward in the radial direction from the end portion on the one side in the axis O direction of the fixed portion 162. A circular hole 163 a centering on the axis O is formed in the overhang portion 163. The circular holes 163a of the overhanging portion 163 are disposed at an interval on the radially outer side of the outer peripheral surface of the sleeve body 25 of the shaft 21. Thus, an axial communication path 164 that is a gap extending over the entire circumference in the circumferential direction is formed by the circular hole 163 a of the overhang portion 163 and the outer peripheral surface of the sleeve body 25 of the shaft 21. That is, the dam member 161 forms an axial communication path 164 that communicates the inner space S1 of the oil containing space S and the space on one side of the dam member 161 in the axis O direction.

In the electric motor 10 </ b> A of the second embodiment, the cooling oil stored in the oil storage space S is discharged to the outside of the oil storage space S through the axial communication path 164 in addition to the upper discharge path 51. This cooling oil is introduced into the accommodation space R <b> 1 in the casing 30 via the bearing device 56.
In the second embodiment, since the cooling oil is directly discharged from the inner space S1, the cooling oil can be smoothly replaced in the inner space S1. Therefore, cooling of the sealing device 160 by the cooling oil in the inner space S1 can be performed more effectively.

  The cross-sectional area of the flow path of the axial communication path 164, that is, the area in the cross-sectional shape orthogonal to the axis O, is set to a dimension that allows at least the inner space S1 of the oil storage space S to be filled with cooling oil. preferable. If the amount of cooling oil supplied into the oil storage space S by the cooling oil supply passage 50 is large, the flow passage cross-sectional area of the axial communication passage 164 can be increased accordingly. That is, the flow passage cross-sectional area of the axial communication passage 164 is determined by the amount of cooling oil supplied by the cooling oil supply passage 50.

<Third embodiment>
An electric motor 10B according to a third embodiment will be described with reference to FIG. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The electric motor 10 </ b> B of the third embodiment is different from the first embodiment in that a lower discharge path (cooling oil discharge path) 170 is formed in the second lid portion 40 in the casing 30.

  The lower discharge path 170 is a flow path formed in the second lid portion 40 and is formed in the lower portion of the second lid portion 40. One end of the lower discharge path 170 is connected to the lower end of the bottom surface 48a of the annular groove 48 of the penetrating portion 41, that is, the lower end of the oil containing space S from the outside in the radial direction. The other end of the lower discharge path 170 is open to the first surface 40a on one side of the second lid 40 in the direction of the axis O. That is, the lower discharge path 170 is formed between the lower part of the oil containing space S (the part below the sliding portions 87 and 97 of the second seal member 80 and the third seal member 90) and the containing space R1 (the third seal member 90). A space on one side of the axis O direction is communicated.

  In the electric motor 10 </ b> B of the third embodiment, the cooling oil in the outer space S <b> 2 of the oil containing space S is discharged from the lower discharge path 170 in addition to the upper discharge path 51. Thereby, the replacement of the cooling oil in the outer space S2 can be performed smoothly, and the temperature of the cooling oil in the outer space S2 can be maintained at a low temperature. Therefore, relatively low-temperature cooling oil can be supplied also to the inner space S1 in which the cooling oil circulates with the outer space S2. Thereby, the cooling effect of the sealing device 60 can be improved.

  The lower discharge path 170 is preferably formed to have a diameter sufficient to fill the cooling oil up to the height of the upper discharge path 51 in the oil containing space S. When the diameter dimension of the lower discharge path 170 is too large, the cooling oil discharged from the lower discharge path 170 becomes excessive, so that the cooling oil does not accumulate in the oil containing space S. It is preferable that the diameter of the lower discharge path 170 is smaller than the diameter of the cooling oil supply path 50. A throttle may be provided in the lower discharge path 170 to adjust the cooling oil to accumulate in the oil storage space S.

<Fourth embodiment>
An electric motor 10C according to a fourth embodiment will be described with reference to FIG. In the fourth embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The cooling oil supply path 50 in the electric motor 10 of the first embodiment is formed in the casing 30, whereas the cooling oil supply path 180 in the electric motor 10 </ b> C of the fourth embodiment is formed in the shaft 21. This is different from the first embodiment.

The cooling oil supply path 180 is formed by an in-shaft channel 181 formed in the shaft body 22 of the shaft 21 and a sleeve channel 182 that penetrates the sleeve body 25 of the sleeve 24 in the radial direction.
The in-shaft channel 181 is connected to, for example, a shaft center hole 23 (not shown in FIG. 8), and cooling oil flowing through the shaft center hole 23 is supplied to the in-shaft channel 181. The cooling oil that has flowed through the in-shaft channel 181 is supplied to the inner space S1 of the oil containing space S through the sleeve channel 182. Also by this, like the first embodiment, the second seal member 80 and the third seal member 90 can always be in contact with the cooling oil.

<Fifth embodiment>
An electric motor 10D according to a fifth embodiment will be described with reference to FIG. In the fifth embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
The electric motor 10D of the fifth embodiment is different from the first embodiment in that a lower discharge path (cooling oil discharge path) 171 is formed in the second lid portion 40 of the casing 30.

  The lower discharge path 171 is a hole formed in a circumferential position different from the upper discharge path 51 in the same manner as the upper discharge path 51. One end of the lower discharge path 171 opens in a portion below the sliding portions 87 and 97 of the second seal member 80 and the third seal member 90 in the oil storage space S. In the present embodiment, one end of the lower discharge path 171 opens on a line extending downward from the vertical line L. The other end of the lower discharge path 171 is open to a space with which the second step surface 46 is in contact (a space on one side of the third seal member 90 in the axis O direction, see FIG. 4). The flow passage cross-sectional area of the lower discharge passage 171 (the cross-sectional area perpendicular to the axis O) is smaller than the flow passage cross-sectional area of the upper discharge passage 51.

  In the electric motor 10 </ b> D of the fifth embodiment, the cooling oil in the outer space S <b> 2 of the oil containing space S is discharged from the lower discharge path 171 in addition to the upper discharge path 51. Thereby, like 3rd embodiment, replacement | exchange of the cooling oil in outer side space S2 can be performed smoothly, and the temperature of the cooling oil of outer side space S2 can be maintained at low temperature. Further, since the flow passage cross-sectional area of the lower discharge passage 171 is smaller than the flow passage cross-sectional area of the upper discharge passage 51, the cooling oil does not flow out from the lower discharge passage 171 excessively. Therefore, the state in which the inside of the oil storage space S is filled with the cooling oil can be maintained.

<Other embodiments>
The embodiment of the present invention has been described above, but the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the present invention.
For example, the sealing device 60 of the first embodiment includes the first seal member 70, the second seal member 80, and the third seal member 90, but may not include the first seal member 70.

  In the first embodiment, the first seal member 70, the second seal member 80, and the third seal member 90 are fixed to the second inner peripheral surface 47 of the wall surface 42 of the penetrating portion 41, and the sliding portions 77, 87, 97 is configured to come into contact with the shaft 21, but the opposite may be possible. That is, the first seal member 70, the second seal member 80, and the third seal member 90 are fixed to the shaft 21, and the sliding portions 77, 87, 97 are the second inner peripheral surface of the wall surface 42 of the penetration portion 41. The structure which contacts 47 may be sufficient.

  In the first embodiment, the configuration in which the oil containing space S is formed over the entire circumferential direction of the shaft 21 has been described. However, the oil containing space S is formed only over a part in the circumferential direction of the shaft 21. May be.

In each embodiment, the ring member 105 may not be provided, and the annular groove 48 may not be formed in the wall surface 42 of the penetrating portion 41. Also by this, if the oil bath state of the sealing device 60 is made, the high temperature and deterioration of the second seal member 80 and the third seal member 90 can be suppressed.
In each embodiment, even if the first seal member 70 and the second seal member 80 are filled with the cooling oil, the first seal member 70 and the second seal member 80 are in an oil bath state. Good.

In each embodiment, by providing an annular member on the other axial side of the first seal member 70, the oil containing space S is defined by the first seal member 70 and the annular member and the wall surface 42 of the through portion 41. There may be.
In each embodiment, a plurality of cooling oil supply paths 50 and 180 may be formed. A plurality of upper discharge paths 51 may be formed.

  In the first embodiment, the upper discharge path 51 is formed above the second seal member 80 and the third seal member 90. However, the upper discharge path 51 has at least the second seal member 80 and the third seal member 90. What is necessary is just to be formed above the sliding parts 87 and 97. FIG. As a result, the sliding portions 87 and 97 of the second seal member 80 and the third seal member 90 that are particularly likely to be at high temperatures can be brought into the oil bath state.

In the first embodiment, the cooling oil that has circulated through the upper discharge passage 51 is configured to pass through the bearing device 56, but may not pass through the bearing device 56.
You may use together the cooling oil supply path 50 of 1st embodiment, and the cooling oil supply path 180 of 4th embodiment.
The lower discharge passages 170 and 171 of the third embodiment and the fifth embodiment may be applied, and the cooling oil supply passage 180 of the fourth embodiment may be applied to the second embodiment.
In the third embodiment and the fifth embodiment, the cooling oil may be discharged only by the lower discharge paths 170 and 171 without forming the upper discharge path 51.

  In the first embodiment, as illustrated in FIG. 5, the example in which the cooling oil supply path 50 is formed at a position shifted in the circumferential direction with respect to the vertical line L has been described. This is because, when the positional relationship between the cooling oil supply path 50 and the lubricating oil supply path 52 is close to each other in the direction of the axis O, the cooling oil supply path 50 and the lubricating oil supply path 52 interfere with each other. This is to avoid that. When a sufficient distance between the cooling oil supply path 50 and the lubricating oil supply path 52 in the direction of the axis O can be secured, the cooling oil supply path 50 is formed along the vertical line L in the same manner as the lubricating oil supply path 52. May be. Even in this case, the cooling oil supply passage 50 and the upper discharge passage 51 are preferably formed at different circumferential positions, that is, the upper discharge passage 51 is displaced in the circumferential direction with respect to the vertical line L. It is preferable that they are formed at different positions.

In 2nd embodiment, although the example which forms the clearance gap between these by the dam member 161 and the shaft 21 as the axial direction communication path 164 was demonstrated, the axial direction formed in the dam member 161 as an axial direction communication path You may employ | adopt. In this case, the dam member 161 may be slidably in contact with the shaft 21 at the radially inner end.
The damming member 161 may be fixed to the shaft 21, and the gap between the penetration part 41 and the wall surface 42 may be formed as an axial communication path. Also in this case, a through-hole in the direction of the axis O formed in the damming member 161 may be used as the axial communication path 164.

In the first embodiment, the configuration in which the lubricating oil supply path 52 is formed in the casing 30 of the electric motor 10 has been described, but the lubricating oil supply path 52 may be formed in the speed reducer casing 120.
In the first embodiment, the example in which the planetary gear device 130 is used as the gear portion has been described. However, another gear device may be provided in the speed reducer 110 as the gear portion.

In each of the embodiments, the axis O is aligned in the horizontal direction, and the so-called laterally mounted motor 1 and motors 10, 10A, 10B, 10C, and 10D are described. The present invention may be applied to an electric motor with a speed reducer and an electric motor, or the present invention may be applied to an electric motor with a speed reducer and an electric motor whose axes are aligned in an oblique direction.
Further, when the electric motors 10, 10 </ b> A, 10 </ b> B, 10 </ b> C, and 10 </ b> D are placed horizontally, the axis O may be made to coincide with the front-rear direction of the wheel loader 200.
Although 1st embodiment demonstrated the example of the electric motor 1 with a reduction gear in which the electric motor 10 was united with the reduction gear 110, you may connect the electric motors 10, 10A, 10B, 10C, and 10D to another apparatus. You may apply this invention to the electric motor 10, 10A, 10B, 10C, 10D single-piece | unit which does not have the reduction gear 110. FIG.

  In each embodiment, although the example which applied the motor 1 with a reduction gear to the wheel loader 200 as a construction machine was demonstrated, you may apply the motor 1 with a reduction gear of this embodiment to another construction machine. The electric motors 10, 10A, 10B, 10C, and 10D may be connected to various devices of the construction machine without using the reduction gear 110. Also in this case, the high temperature in the sealing device 60 in the electric motors 10, 10A, 10B, 10C, 10D can be suppressed.

DESCRIPTION OF SYMBOLS 1 ... Electric motor with a reduction gear, 10 ... Electric motor, 10A ... Electric motor, 10B ... Electric motor, 10C ... Electric motor, 10D ... Electric motor, 20 ... Rotor, 21 ... Shaft, 22 ... Shaft main body, 22a ... Fixed outer peripheral surface, 23 ... Shaft center Hole, 24 ... Sleeve, 25 ... Sleeve body, 26 ... Flange, 27 ... Rotor core, 28a ... First end plate, 28b ... Second end plate, 29a ... First cooling channel, 29b ... Second cooling channel, DESCRIPTION OF SYMBOLS 30 ... Casing, 31 ... Cylindrical part, 32 ... Cooling oil introduction path, 33 ... Cooling oil extraction path, 34 ... First cover part, 35 ... Shaft accommodating part, 36 ... Cooling oil introduction hole, 37 ... End bearing, 38 ... end seal, 40 ... second lid, 40a ... first surface, 40b ... second surface, 41 ... penetrating portion, 42 ... wall surface, 43 ... bearing fixing surface, 44 ... first step surface, 45 ... first One inner circumferential surface, 46 ... second stage Surface 47, second inner peripheral surface (inner peripheral surface), 48 annular groove, 48a bottom surface, 48b first inner surface, 48c second inner surface, 50 cooling oil supply path, 51 upper discharge path (Cooling oil discharge passage), 52 ... lubricating oil supply passage, 53 ... branch passage, 54 ... gas reservoir, 56 ... bearing device, 57 ... outer ring, 58 ... inner ring, 59 ... rolling element, 60 ... sealing device, 70 ... First seal member, 76 ... Lip part, 77 ... Sliding part, 80 ... Second seal member (seal member), 86 ... Lip part, 87 ... Sliding part, 90 ... Third seal member, 96 ... Lip part, 97 ... Sliding part, 100 ... Cooling oil supply part, 101 ... Cooling oil circulation channel, 102 ... Cooling oil pump, 103 ... Cooling oil cooling part, 105 ... Ring member, 106 ... Communication hole, 110 ... Speed reducer, 120 ... Reduction gear casing, 121 ... Reduction gear penetration, 122 ... Bearing lubrication flow path, 12 DESCRIPTION OF SYMBOLS ... Lubricating oil discharge hole, 124 ... Reduction gear bearing, 130 ... Planetary gear unit (gear part), 131 ... Sun gear, 132 ... Planetary carrier, 133 ... Carrier channel, 134 ... Planetary gear, 135 ... Gear channel , 136 ... internal gear, 140 ... output shaft, 141 ... connection part, 150 ... lubricating oil supply part, 151 ... lubricating oil circulation flow path, 152 ... lubricating oil pump, 153 ... lubricating oil cooling part, 160 ... sealing device, 161 ... Damming member, 162 ... Fixed part, 163 ... Overhang part, 163a ... Circular hole, 164 ... Axial communication path, 170 ... Lower discharge path (cooling oil discharge path), 171 ... Lower discharge path (cooling oil discharge path) , 180 ... cooling oil supply passage, 181 ... shaft passage, 182 ... sleeve passage, 190 ... stator, 191 ... stator core, 191a ... yoke, 191b ... teeth, 192 ... coil, 200 DESCRIPTION OF SYMBOLS ... Wheel loader, 210 ... Vehicle body, 211 ... Vehicle body, 212 ... Cab, 220 ... Working machine, 221 ... Lift arm, 223 ... Bucket, 230 ... Drive device, 231 ... Engine, 232 ... Transmission device, 233A, 233B ... Propeller Shaft, 234A, 234B ... Differential gear, 235A, 235B ... Drive shaft, 236 ... Front wheel, 237 ... Rear wheel, R1 ... Housing space, R2 ... Gear housing space, S ... Oil housing space, S1 ... Inside space, S2 ... Outside Space, O ... axis, P ... center axis, L ... vertical line, Q ... reference line

Claims (8)

A shaft that rotates around an axis, and a rotor having a rotor core that is fixed radially outward of the shaft;
A stator surrounding the rotor core from the outer peripheral side;
A casing that houses the rotor core and the stator, and that has a penetrating portion through which the shaft penetrates in the axial direction;
It is fixed to one of the wall surface of the penetrating part and the outer peripheral surface of the shaft facing each other and extends in the circumferential direction of the shaft. A seal member having a sliding portion in contact with the direction;
An annular member provided on the one axial side of the seal member between the wall surface of the penetrating portion and the outer peripheral surface of the shaft and spaced apart from the seal member, and extending in the circumferential direction;
With
At least one of the casing and the shaft has a cooling oil supply path for supplying cooling oil between the seal member and the annular member,
The electric motor in which the casing has a cooling oil discharge passage for discharging the cooling oil from between the seal member and the annular member.   A space between the seal member and the annular member is partitioned between the seal member and the annular member into an inner space that is in contact with the sliding portion and an outer space that is radially outward of the inner space. The electric motor according to claim 1, further comprising a ring member having a plurality of communication holes arranged at intervals in the circumferential direction so as to communicate the inner space and the outer space.   3. The electric motor according to claim 1, wherein a wall surface of the penetrating portion has an annular groove that is recessed outward in the radial direction and extends in the circumferential direction at a portion between the seal member and the annular member. The cooling oil supply path is formed in the casing;
The electric motor according to any one of claims 1 to 3, wherein the circumferential positions of the cooling oil supply path and the cooling oil discharge path are different from each other. The axis extends in a horizontal direction;
The cooling oil discharge path is an upper discharge path that communicates the space between the seal member and the annular member and the space on one side in the axial direction of the annular member above the sliding portion. The electric motor as described in any one of Claim 1 to 4 containing. The axis extends in a horizontal direction;
The cooling oil discharge path is a lower discharge path that communicates the space between the seal member and the annular member and the space on one side in the axial direction of the annular member below the sliding portion. The electric motor as described in any one of Claim 1 to 5 containing. A shaft that rotates about an axis extending in the horizontal direction, and a rotor having a rotor core that is fixed radially outward of the shaft;
A stator surrounding the rotor core from the outer peripheral side;
A casing that houses the rotor core and the stator, and that has a penetrating portion through which the shaft passes from one side in the axial direction toward the other side;
With
The penetrating portion has a wall surface including an inner peripheral surface extending in the axial direction facing the outer peripheral surface of the shaft, and an annular groove extending in the radial direction from the inner peripheral surface to the outer side in the radial direction. ,
A seal member having a sliding portion fixed to the other axial side of the annular groove on the inner peripheral surface of the wall surface and extending in the circumferential direction of the shaft and in contact with the outer peripheral surface of the shaft in the circumferential direction When,
An annular member provided on one side in the axial direction of the annular groove between the wall surface of the penetrating portion and the outer peripheral surface of the shaft, and extending over the circumferential direction;
Provided between the seal member and the annular member, an inner space where the sliding portion is in contact with a space between the seal member and the annular member, and an outer space on the radially outer side of the inner space. And a ring member having a plurality of communication holes arranged at intervals in the circumferential direction so as to communicate with the inner space and the outer space,
The casing is
A cooling oil supply path that communicates with the outer space and supplies cooling oil between the seal member and the annular member;
Formed in the circumferential position different from the cooling oil supply path above the sliding portion, a space between the seal member and the annular member, and a space on one axial direction side of the annular member, And a cooling oil discharge passage including an upper discharge passage for communicating the electric motor. An electric motor according to any one of claims 1 to 7,
A gear portion connected to the other side of the shaft in the axial direction than the seal member in the shaft, a speed reducer casing that houses the gear portion, and a gear portion that is rotatably supported by the speed reducer casing. A speed reducer having an output shaft through which rotation of the shaft is transmitted;
With
An electric motor with a reduction gear, wherein at least one of the casing and the reduction gear casing has a lubricating oil supply path for supplying lubricating oil to the gear portion.

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