Motor unit of industrial vehicle

Abstract

Provided is a motor unit for an industrial vehicle capable of suppressing intrusion of foreign matter into a rotation sensor without increasing the number of components. The rotor shaft (41) has a shaft part (46) protruding from the end bracket (37) toward the output unit part, the output unit part has: a motor support body connected to the end bracket (37) and forming an insertion space (57) through which the shaft part (46) can be inserted, and the rotation sensor has: a sensor rotor part provided on the shaft part and rotating integrally with the rotor shaft (41); and a sensor stator part that is provided to the end bracket (37) so as to face the sensor rotor part, the end bracket (37) having a sensor housing space (80) in which the rotation sensor is housed.

Description

TECHNICAL FIELD

[0001] The present application relates to a motor unit of an industrial vehicle. BACKGROUND

[0002] As a motor unit of an industrial vehicle, for example, a cargo handling industrial vehicle disclosed in Patent Literature 1 is known. In Patent Literature 1, a stand-up type industrial vehicle called a reach truck is disclosed as a cargo handling industrial vehicle. The stand-up type industrial vehicle is provided with a gear motor in which a reducer portion is located at a lower side and a motor portion is located at an upper side of the reducer portion. A rotation speed detection sensor that detects rotation of a rotor shaft is provided in the motor portion, but the rotation speed detection sensor is provided at an upper portion of the motor portion.

[0003] Prior art documents

[0004] Patent documents

[0005] Patent Literature 1: Japanese Patent Application Laid-Open No. 2004-203516 SUMMARY

[0006] Problems to be solved by the invention

[0007] However, in the gear motor of the stand-up type industrial vehicle disclosed in Patent Literature 1, in a case where it is necessary to suppress intrusion of foreign matters such as water, dust, and the like into the rotation sensor (rotation speed detection sensor) provided at the upper portion of the motor portion, for example, a sealing member, a cover member, or the like for suppressing intrusion of foreign matters is necessary. Therefore, there is a problem that the number of components of the motor unit (gear motor) as an industrial vehicle increases, and the manufacturing cost of the motor unit increases. In addition, in a case where the rotation sensor is a resolver, a waterproof countermeasure for the resolver is necessary.

[0008] The present application has been achieved in view of the above-described problems, and an object of the present application is to provide a motor unit of an industrial vehicle that can suppress intrusion of foreign matters into a rotation sensor without increasing the number of components.

[0009] Solution to the problem

[0010] To solve the above problems, the present application is a motor unit of an industrial vehicle, having: an electric motor section; an output unit section connected to the electric motor section; and a rotation sensor that detects a rotation angle or a rotation speed of the electric motor section, the electric motor section having: a stator; a rotor disposed inside the stator, having a rotor shaft; and an end bracket connected to the stator, axially supporting an output side of the rotor shaft, the motor unit of the industrial vehicle being characterized in that the rotor shaft has a shaft portion protruding from the end bracket toward the output unit section side, the output unit section has: a motor support connected to the end bracket, forming a through space through which the shaft portion can pass, and the rotation sensor has: a sensor rotor portion provided to the shaft portion, rotating integrally with the rotor shaft; and a sensor stator portion provided to the end bracket in a manner opposite to the sensor rotor portion, the end bracket having a sensor housing space that houses the rotation sensor.

[0011] In the present application, the rotor shaft has a shaft portion protruding from the end bracket toward the output unit section side. The output unit section has: a motor support connected to the end bracket, forming a through space through which the shaft portion can pass. The end bracket is connected to the motor support, and the through space through which the shaft portion can pass is formed in the motor support. The rotation sensor is housed in the sensor housing space provided to the end bracket. Since the end bracket is connected to the motor support, the intrusion of foreign matter into the sensor housing space is suppressed. Since the intrusion of foreign matter into the sensor housing space is suppressed by the connection of the end bracket to the motor support, components or the like for suppressing the intrusion of foreign matter are not additionally required. Thus, the number of components of the motor unit does not increase, and the manufacturing cost can be suppressed.

[0012] Further, in the above-described motor unit of an industrial vehicle, the motor support can have an engagement portion that engages with the end bracket, and the end bracket can have an engaged portion that engages with the engagement portion.

[0013] In this case, by engaging the engagement portion of the motor support with the engaged portion of the end bracket, the through space is blocked from the outside. As a result, the intrusion of foreign matter through the through space into the sensor housing space is hindered, and the intrusion of foreign matter into the sensor housing space can be further suppressed.

[0014] Further, in the above-described motor unit of an industrial vehicle, the motor support can have an engagement portion that engages with the end bracket, and the end bracket can have an engaged portion that engages with the engagement portion.

[0015] In this case, since the motor support body is located lower than the end bracket, the sensor housing space in which the rotation sensor is housed becomes the lower side of the end bracket, and the insertion space becomes lower than the sensor housing space. Therefore, intrusion of foreign matter through the insertion space into the sensor housing space becomes intrusion in the direction opposite to the gravity, and thus intrusion of foreign matter into the sensor housing space can be further suppressed.

[0016] In addition, in the motor unit for industrial vehicle described above, the motor support body can be configured to have an end surface opposite to the end bracket and a protruding portion protruding from the end surface toward the end bracket, and the fitting portion can be provided to the protruding portion.

[0017] In this case, since the fitting portion is provided to the protruding portion, in order for foreign matter to pass through between the fitting portion and the fitted portion from the end surface, the foreign matter needs to pass over the protruding portion, and it is difficult for the foreign matter to intrude into the sensor housing space from between the fitting portion and the fitted portion.

[0018] In addition, in the motor unit for industrial vehicle described above, a gasket can be provided between the fitting portion and the fitted portion.

[0019] In this case, since the gasket is provided between the fitting portion and the fitted portion, even if foreign matter attempts to intrude between the fitting portion and the fitted portion, the gasket blocks the foreign matter. Thus, intrusion of foreign matter into the sensor housing space can be prevented.

[0020] In addition, in the motor unit for industrial vehicle described above, a partition member can be provided to separate the insertion space from the sensor housing space.

[0021] In this case, since the partition member separates the insertion space from the sensor housing space, even if foreign matter intrudes into the insertion space, the foreign matter is blocked by the partition member, and it is difficult for the foreign matter to intrude into the sensor housing space. As a result, intrusion of foreign matter into the sensor housing space can be more reliably suppressed.

[0022] In addition, in the motor unit for industrial vehicle described above, the rotation sensor can be a resolver.

[0023] In this case, since the rotation sensor is a resolver, the resolver can detect the rotation angle of the rotor shaft.

[0024] Effects of the invention

[0025] According to the present application, a motor unit for industrial vehicle that can suppress intrusion of foreign matter into a rotation sensor without increasing the number of components can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 This is a top view of the forklift with outreach capability according to the first embodiment.

[0027] Figure 2 This is a side view of the forklift with outreach capability according to the first embodiment.

[0028] Figure 3 This is a perspective view of the forklift with outreach capability according to the first embodiment.

[0029] Figure 4 This is a rear view of the drive unit of a forklift.

[0030] Figure 5 This is a longitudinal cross-sectional view of the main part of the drive unit of a forklift.

[0031] Figure 6 It is an enlarged cross-sectional view showing the main part of the drive unit.

[0032] Figure 7 This is a bottom view of the resolver.

[0033] Figure 8 This is a front view of the main parts of the counterweight forklift in the second embodiment.

[0034] Figure 9 This is a longitudinal cross-sectional view of the main part of the motor unit in the second embodiment.

[0035] Explanation of reference numerals

[0036] 10-way forklift

[0037] 11, 91 car body

[0038] 12. Main body of the vehicle

[0039] 15 Cargo loading and unloading equipment

[0040] 19 forks

[0041] 21 Lifting Cylinder

[0042] 22 Rear Wheels

[0043] 23 Driver's Seat

[0044] 25 steering handle

[0045] 26. Steering Pole

[0046] 30 drive units

[0047] 31. Motor section for driving

[0048] 32. Gear Unit (Output Unit)

[0049] 33 steering motor section

[0050] 34 stator

[0051] 35 rotor

[0052] 36 end bracket

[0053] 41 rotor shaft

[0054] 45, 46 shaft portion

[0055] 47 brake disc

[0056] 51 support arm

[0057] 52 gear housing

[0058] 53 rotation transmission mechanism

[0059] 55 end surface

[0060] 56 protrusion (fitting portion)

[0061] 57, 97 insertion space

[0062] 70 resolver

[0063] 80 sensor housing space

[0064] 86 protrusion (fitted portion)

[0065] 87, 99 liquid gasket

[0066] 88 circular plate-shaped cover

[0067] 90 counterbalance type forklift truck

[0068] 94 motor unit

[0069] 95 output unit section

[0070] 96 motor support

[0071] 98 fitting portion

[0072] P shaft center DETAILED DESCRIPTION

[0073] (First Embodiment)

[0074] A motor unit of an industrial vehicle according to the first embodiment will be described below with reference to the drawings. The industrial vehicle of the present embodiment is a reach truck (hereinafter simply referred to as "forklift truck"). Also, with respect to the directions "front and rear", "left and right", and "up and down", a state in which an operator of the forklift truck is standing on a standing driver's seat and facing a forward direction of the forklift truck is taken as a reference.

[0075] First of all, Figure 1 The forklift 10 shown will be described below. The forklift 10 has a body 11 with a main body 12 and a pair of left and right outriggers 13 (13R, 13L) extending forward from the front of the main body 12. Each outrigger 13 has a freely rotatable driven wheel 14, equivalent to a front wheel. The right driven wheel is designated as driven wheel 14R, and the left driven wheel is designated as driven wheel 14L. Figure 2 Only the left-side forward extension leg 13 and the left-side driven wheel 14L are shown. A cargo loading / unloading device 15 is located in front of the vehicle body 11 and between the two forward extension legs 13. The cargo loading / unloading device 15 is supported to allow for forward extension in the forward and backward directions. The forward extension of the cargo loading / unloading device 15 is achieved by the operation of a forward extension cylinder (not shown) located at the rear of the vehicle body 12.

[0076] The cargo loading and unloading device 15 includes an outer mast 16 supported by left and right outriggers 13 and an inner mast 17 supported by the outer mast 16 in a height-adjustable manner. A lifting support member 18 is vertically supported on the inner mast 17. A pair of left and right forks 19 are supported on the front surface of the lifting support member 18. The upper ends of the forks 19 are pivotally supported on the lifting support member 18 in a manner that allows the forks 19 to tilt. Therefore, the forks 19 can tilt and move back and forth. A lifting bracket 20 is provided above the forks 19. A lifting cylinder 21 for raising and lowering the inner mast 17 is fixed behind the outer mast 16.

[0077] like Figure 2 As shown, a rear wheel 22, which serves as both a drive wheel and a steering wheel, is located on the left rear side of the main body 12. A standing driver's seat 23 is located on the right rear side of the main body 11. Figure 3 As shown, casters 24 are supported below the driver's seat 23 in the main body 12. A steering wheel 25 is located on the left side of the driver's seat 23 in the main body 12. Figure 1 As shown, in front of the driver's seat 23 in the main body 12, there is a steering lever 26 for switching forward and backward, a tilt lever 27, a forward extension lever 28, and a lifting lever 29.

[0078] like Figure 4 As shown, the rear wheel 22 is supported on the lower part of the drive unit 30, which is a motor unit installed on the left side of the vehicle body 12. The drive unit 30 has a driving motor 31, which is an electric motor that generates driving force for the rear wheel 22; a gear unit 32, which is an output unit; and a steering motor 33.

[0079] like Figure 5As shown, the driving motor unit 31 includes a stator 34, a rotor 35, and a pair of upper and lower end brackets 36 and 37. The stator 34 has a cylindrical stator core 38 and stator coils 39. The rotor 35 has a rotor core 40 disposed within the stator core 38 and a rotor shaft 41 that passes through the center of the rotor core 40 and is integrated with the rotor core 40. A permanent magnet (not shown) is embedded in the rotor core 40. The driving motor unit 31 is a magnet-embedded synchronous motor.

[0080] The drive motor unit 31 is configured such that the axis P of the rotor shaft 41 intersects the horizontal direction. In this embodiment, the axis P of the rotor shaft 41 is oriented approximately vertically. That is, the drive unit 30 is longitudinally positioned. The end bracket 36 is connected to the upper part of the stator 34, and the end bracket 37 is connected to the lower part of the stator 34. The end bracket 36 provides shaft support near the upper end of the rotor shaft 41 via a bearing 42, and the end bracket 37 provides shaft support near the lower end, which is the output side of the rotor shaft 41, via a bearing 43. Details of the end bracket 37 will be described later.

[0081] like Figure 5 As shown, the rotor shaft 41 has: a main shaft portion 44 located within the stator core 38; a shaft portion 45 protruding upward from the end bracket 36; and a shaft portion 46 protruding from the end bracket 37 toward the gear unit portion 32. A brake disc 47 is provided in the shaft portion 45. The end bracket 37 is supported by the gear unit portion 32.

[0082] The gear unit 32 includes: a support arm 51 that supports the drive motor 31; a gear housing 52 disposed at the lower part of the support arm 51 and supporting the rear wheel 22; and a rotation transmission mechanism 53 housed within the gear housing 52. The support arm 51 functions as a motor support. The support arm 51 is formed in a generally crank shape and supports the drive motor 31 by connecting to an end bracket 37. The front part of the support arm 51 has a rotating shaft 54, which can rotate relative to the vehicle body 12 (see reference). Figure 2 In other words, the support arm 51 is connected to the vehicle body 12 via the rotating shaft 54.

[0083] like Figure 5 As shown, the support arm 51 has an end face 55 opposite to the end bracket 37. The end face 55 is a generally horizontal surface. The end face 55 has a protrusion 56 that protrudes from the end face 55 toward the end bracket 37. The protrusion 56 is formed in a ring shape in the end face 55 in a manner concentric with the axis P. In the support arm 51, an insertion space 57 is formed for the shaft portion 46 to be inserted.

[0084] The gear housing 52 provided at the lower portion of the support arm 51 has an upper housing 58 and a lower housing 59. At the upper portion of the upper housing 58, a cylindrical portion 58A is formed. The cylindrical portion 58A is inserted into the insertion space 57 of the support arm 51. The cylindrical portion 58A is rotatably supported with respect to the support arm 51 via bearings 61, 62. Thus, the gear housing 52 is rotatable with respect to the support arm 51.

[0085] The lower portion of the upper housing 58 is joined with the lower housing 59. In the cylindrical portion 58A, not only a portion of the shaft portion 46 is inserted, but also a gear shaft 63, which is a part of the rotation transmission mechanism 53, is coaxially inserted with the rotor shaft 41. The gear shaft 63 has a gear 64, which is supported by the upper housing 58 and the lower housing 59 via bearings 65, 66. A shaft joint 67, which is connected with the shaft portion 46 and the gear shaft 63, is inserted into the cylindrical portion 58A. The shaft joint 67 is rotatable with respect to the upper housing 58. The gear 64 of the gear shaft 63 is engaged with another gear (not shown) of the rotation transmission mechanism 53 housed in the gear housing 52. The rotation transmission mechanism 53 has a plurality of gears including the gear 64, and the rotation of the rotor shaft 41 is transmitted to the rear wheel 22 by the rotation transmission mechanism 53.

[0086] A gear wheel 68 is provided at the upper portion of the gear housing 52. A steering motor portion 33 (refer to Figure 4 ) is provided beside the traveling motor portion 31 in the support arm 51. The gear wheel 68 is rotated by the drive of the steering motor portion 33. The steering motor portion 33 is controlled by a steering shaft (not shown) or the like connected with the steering handle 25 via a steering shaft (not shown) or the like. Thus, according to the amount of rotation of the steering handle 25, the steering motor portion 33 is driven, and the rear wheel 22 is steered.

[0087] As shown in Figure 6 , the drive unit 30 of the present embodiment has a resolver 70 as a rotation sensor that detects the rotation angle of the rotor shaft 41. As shown in Figure 7 , the resolver 70 has a resolver rotor 71, a resolver stator 72, and a wiring 73. The resolver rotor 71 corresponds to the sensor rotor portion, and the resolver stator 72 corresponds to the sensor stator portion.

[0088] The resolver rotor 71 is fixed to the shaft portion 46 of the rotor shaft 41 and rotates integrally with the rotor shaft 41. A nut 74 that prevents detachment from the shaft portion 46 of the resolver rotor 71 is tightened to the shaft portion 46. The resolver stator 72 is fixed to the end bracket 37 by bolts 75 and surrounds the resolver rotor 71. The resolver stator 72 has a stator core (not shown) and a coil wound to the stator core (not shown). The resolver stator 72 is provided with a wiring 73 connected to the coil. The wiring 73 is connected to a controller (not shown) that controls the travel motor portion 31. A resolver signal constituted by 2-phase outputs detected after rotation of the resolver rotor 71 is transmitted to the controller via the wiring 73 by rotation of the resolver rotor 71.

[0089] The end bracket 37 of the present embodiment forms a sensor housing space 80 that communicates with the insertion space 57 of the support arm 51. Here, the end bracket 37 is described in detail. As shown in FIG. 6, the end bracket 37 has an end wall portion 81, a motor side peripheral wall portion 82, and a support arm side peripheral wall portion 83. The end wall portion 81 is a substantially circular wall portion that extends in a direction substantially orthogonal to the axis P of the rotor shaft 41. In the center of the end wall portion 81, an axial hole 81A is formed through which the shaft portion 46 is inserted, and the bearing 43 that supports the rotor shaft 41 is provided in the axial hole 81A. The motor side peripheral wall portion 82 is a substantially cylindrical wall portion that extends from the outer periphery of the end wall portion 81 toward the stator core 38, and the top end portion of the motor side peripheral wall portion 82 is joined to the stator core 38. Figure 6

[0090] The support arm side peripheral wall portion 83 is a substantially cylindrical wall portion that extends from the outer periphery of the end wall portion 81 toward the support arm 51. The sensor housing space 80 is formed by the end wall portion 81 and the support arm side peripheral wall portion 83. The end face of the end wall portion 81 on the sensor housing space 80 side is formed with a step 84 that matches the shape of the resolver stator 72. The resolver stator 72 is fixed to the end bracket 37 by the bolts 75, but can be adjusted in position in the circumferential direction for phase alignment.

[0091] The inner wall surface of the support arm side peripheral wall portion 83 is formed so that the maximum inner diameter of the sensor housing space 80 is substantially the same as the insertion space 57 formed by the support arm 51. A protruding portion 86 that protrudes toward the protruding portion 56 of the support arm 51 is formed in the end face 85 of the support arm side peripheral wall portion 83 in the entire circumferential direction. The protruding portion 86 of the support arm side peripheral wall portion 83 is fitted to the protruding portion 56 of the support arm 51 in the entire circumferential direction by spigot joint. The protruding portion 56 of the support arm 51 corresponds to the fitting portion, and the protruding portion 86 of the end bracket 37 corresponds to the fitted portion. In the protruding portion 86, a stepped portion 86A is formed to which the corner portion 56A of the protruding portion 56 abuts. By abutting the corner portion 56A to the stepped portion 86A, the end bracket 37 is not misaligned in the radial direction with respect to the support arm 51. ​

[0092] In the present embodiment, the fitting of the protruding portion 56 of the support arm 51 and the protruding portion 86 of the end bracket 37 is fitting based on a socket joint, and is a clearance fit. Therefore, a liquid gasket 87 is interposed in a manner that fills the slight gap of the corner portion 56A and the step portion 86A. The liquid gasket 87 is liquid before application, and forms an elastic film or a viscoelastic film as it cures over time after application. As the liquid gasket 87, for example, a silicon-based liquid gasket is used.

[0093] In the present embodiment, a circular plate-shaped cover 88 that separates the sensor housing space 80 and the insertion space 57 is provided to the end bracket 37. The circular plate-shaped cover 88 has a through-hole 89 in the center through which the shaft portion 46 of the rotor shaft 41 is inserted. In the present embodiment, a gap is formed between the outer periphery of the circular plate-shaped cover 88 and the support arm side peripheral wall portion 83, and the circular plate-shaped cover 88 does not completely separate the sensor housing space 80 and the insertion space 57. The circular plate-shaped cover 88 is provided at a position that does not interfere with the rotating rotor shaft 41 and the nut 74. The circular plate-shaped cover 88 has a function of preventing the intrusion of foreign matter from the insertion space 57 to the sensor housing space 80. Furthermore, the circular plate-shaped cover 88 is formed of a cold-rolled material, but as long as it is a material that has heat resistance, it is not particularly limited.

[0094] Next, the operation of the drive unit 30 of the present embodiment will be described. The travel of the forklift 10 is performed by the operation of the operator seated on the driver's seat 23 operating the steering lever 26. The travel motor portion 31 is driven in accordance with the amount of operation of the steering lever 26. The rotational force of the rotor shaft 41 generated by the driving of the travel motor portion 31 is transmitted to the rear wheels 22 via the rotation transmission mechanism 53. By the operation of the operator operating the steering handle 25, the steering motor portion 33 is driven in accordance with the amount of operation of the steering handle 25, the gear housing 52 is swung with respect to the support arm 51, and the rear wheels 22 of the forklift 10 are steered.

[0095] Furthermore, the rotational angle of the rotor shaft 41 is transmitted from the resolver 70 to the controller via the wiring 73 by the resolver signal constituted by the 2-phase output after detection of rotation. The protruding portion 86 of the end bracket 37 and the protruding portion 56 of the support arm 51 are fitted. Water, for example, as foreign matter, sometimes intrudes into the end surface 55 of the support arm 51, but since the protruding portion 56 protrudes upward from the end surface 55, it hardly reaches the fitting surface of the protruding portion 86 and the protruding portion 56. Even if water reaches the fitting surface of the protruding portion 86 and the protruding portion 56, it is hindered from intruding into the insertion space 57 by the liquid gasket 87. Even if water intrudes into the insertion space 57 from the fitting surface of the protruding portion 86 and the protruding portion 56, it goes downward due to gravity, so water hardly intrudes into the sensor housing space 80. Thus, the attachment of water to the resolver 70 is prevented.

[0096] On the other hand, in the travel of the forklift 10, sometimes, fine particles of lubricating oil or fine wear powder as foreign matter can be generated from the sliding portion of the rotation transmission mechanism 53 due to the driving of the travel motor portion 31. Even if such foreign matter is generated and floats to the insertion space 57, the round plate-shaped cover 88 hinders the intrusion of the foreign matter into the sensor housing space 80, and the attachment of the foreign matter to the resolver 70 is prevented.

[0097] The driving unit 30 of the present embodiment has the following effects.

[0098] (1) The rotor shaft 41 has a shaft portion 46 protruding from the end portion bracket 37 toward the output unit portion side. The output unit portion has a support arm 51 as a motor support body connected to the end portion bracket 37, and forms an insertion space 57 through which the shaft portion 46 can be inserted. The end portion bracket 37 is connected to the support arm 51, and the insertion space 57 through which the shaft portion 46 can be inserted is formed in the support arm 51. The resolver 70 is housed in a sensor housing space 80 provided in the end portion bracket 37. Since the end portion bracket 37 is connected to the support arm 51, the intrusion of foreign matter into the sensor housing space 80 is suppressed. Since the intrusion of foreign matter into the sensor housing space 80 is suppressed by the connection of the end portion bracket 37 to the support arm 51, a member or the like for suppressing the intrusion of foreign matter is not required. Thus, the number of members of the motor unit does not increase, and the manufacturing cost of the motor unit can be suppressed.

[0099] (2) The support arm 51 has a fitting portion that is fitted to the end portion bracket 37, and the end portion bracket 37 has a fitted portion that is fitted to the fitting portion by spigot and socket joint. Thus, by fitting the fitting portion of the support arm 51 to the fitted portion of the end portion bracket 37, the insertion space 57 is blocked from the outside. As a result, the intrusion of foreign matter through the insertion space 57 into the sensor housing space 80 is hindered, and the intrusion of foreign matter into the sensor housing space 80 can be further suppressed.

[0100] (3) The axis P of the rotor shaft 41 is orthogonal to the horizontal, and the support arm 51 is positioned lower than the end portion bracket 37. Since the support arm 51 is positioned below the end portion bracket 37, the sensor housing space 80 in which the resolver 70 is housed is on the lower side of the end portion bracket 37, and the insertion space 57 is lower than the sensor housing space 80. Thus, the intrusion of foreign matter through the insertion space 57 into the sensor housing space 80 is intrusion in a direction opposite to the direction of gravity, and the intrusion of foreign matter into the sensor housing space 80 can be further suppressed.

[0101] (4) The support arm 51 has an end surface 55 that opposes the end bracket 37, and a protrusion 56 that protrudes from the end surface 55 toward the end bracket 37 side, and the fitting portion is provided to the protrusion 56. Therefore, in order for a foreign object to pass between the end surface 55 and the fitted portion, it is necessary to pass over the protrusion 56, and it is difficult for a foreign object to intrude from between the fitting portion and the fitted portion into the sensor housing space 80.

[0102] (5) The liquid gasket 87 is interposed between the fitting portion and the fitted portion, and therefore even if a foreign object attempts to intrude between the fitting portion and the fitted portion, it is obstructed by the liquid gasket 87. As a result, intrusion of a foreign object into the sensor housing space 80 is prevented.

[0103] (6) The circular plate-shaped cover 88 separates the insertion space 57 from the sensor housing space 80, and therefore even if a foreign object intrudes into the insertion space 57, it is obstructed by the circular plate-shaped cover 88, and it is difficult to intrude into the sensor housing space 80. As a result, intrusion of a foreign object into the sensor housing space 80 can be more reliably suppressed.

[0104] (7) The rotation sensor is the resolver 70, and therefore the rotation angle of the rotor shaft 41 can be detected by the resolver 70.

[0105] (8) In the existing forklift, the resolver is provided between a disc brake provided near the upper end of the rotor shaft and the upper end bracket. Also, in order to prevent intrusion of a foreign object from the rotor shaft into the resolver, it is necessary to interpose a sealing member between the rotor shaft and the end bracket. Also, in order to obstruct intrusion of a foreign object from the disc brake side, it is necessary to provide a cover member between the resolver and the disc brake. However, in the drive unit 30 of the present embodiment, these sealing member and cover member are not necessary, and the number of components for preventing intrusion of a foreign object toward the resolver 70 can be suppressed.

[0106] (2nd Embodiment)

[0107] Next, the motor unit of the industrial vehicle of the 2nd embodiment will be described. In the present embodiment, the motor unit is laid horizontally, which is different from the 1st embodiment. In the present embodiment, the description of the 1st embodiment is referred to for the same configuration as the 1st embodiment, and common reference numerals are used.

[0108] Figure 8The forklift 90 shown as an industrial vehicle is a counterbalance type forklift. In the front portion of a vehicle body 91 of the forklift 90, a front axle 92 is provided. In the front axle 92, a pair of left and right front wheels 93 as drive wheels are provided. In the front axle 92, a pair of left and right motor units 94 are provided. The motor unit 94 has a traveling motor section 31 as an electric motor section, and an output unit section 95. Since the traveling motor section 31 is laid horizontally, the axis P of the rotor shaft 41 is substantially horizontal. The rotation of the rotor shaft 41 is transmitted to the front wheels 93 via the output unit section 95.

[0109] The output unit section 95 has a motor support body 96 connected to the end bracket 37, forming a through space 97 through which the shaft section 46 can be inserted. As shown in Figure 9 The end bracket 37 has a sensor housing space 80 in which the resolver 70 is housed. The motor support body 96 has an engaging section 98 that engages with the protruding section 86 of the end bracket 37 by spigot and socket joint. The engaging section 98 of the motor support body 96 and the protruding section 86 of the end bracket 37 as the engaged section block the through space 97 from the outside. A liquid gasket 99 is interposed between the protruding section 86 and the engaging section 98. In addition, a circular plate-shaped cover 88 as a partition member that separates the sensor housing space 80 and the through space 97 is provided to the end bracket 37.

[0110] According to the motor unit 94 of the present embodiment, the same effects as those of the first embodiment (1) are obtained. In addition, even if the motor unit 94 is laid horizontally, the liquid gasket 99 can prevent the intrusion of foreign matter from the outside of the motor unit 94 into the sensor housing space 80.

[0111] The present application is not limited to the above-described embodiments, and various modifications can be made within the scope of the gist of the application. For example, the following modifications can be made.

[0112] In the above-described embodiments, the motor support body has an end surface opposite the end bracket and a protruding section that protrudes from the end surface toward the end bracket side, but is not limited thereto. For example, a motor support body that does not have a protruding section can be used.

[0113] In the above-described embodiments, a liquid gasket is interposed between the engaging section and the engaged section, but is not limited thereto. For example, a gasket made of metal can be interposed instead of the liquid gasket. In addition, if the motor unit is laid vertically and the motor support body has a protruding section, a gasket can not be interposed.

[0114] In the above-described embodiments, the motor unit has a partition member that separates the through space and the sensor housing space, but is not limited thereto. For example, a motor unit that does not have a partition member can be used. Furthermore, the shape of the partition member is not limited to that of the above-described embodiments, and can be any shape that can prevent the intrusion of foreign matter from the through space into the sensor housing space.

[0115] In the above embodiment, the resolver is exemplified as the rotation sensor, but is not limited thereto. The rotation sensor can be, for example, a relative position sensor capable of outputting a z-pulse in addition to two-phase pulse train signals (a-pulse, b-pulse), or a TMR sensor. In addition, the rotation sensor can be a sensor that detects the rotational speed of the electric motor portion, and can detect, for example, the number of revolutions per unit time (1 minute) of the rotor shaft as the rotational speed of the electric motor portion.

[0116] In the above embodiment, the forklift is exemplified as the industrial vehicle, but is not limited thereto. The industrial vehicle can be, for example, a tractor, a trailer, or an automated guided vehicle, as long as it is an industrial vehicle capable of traveling by an electric motor.

Claims

1. A motor unit for an industrial vehicle, comprising: Electric motor section; The output unit is connected to the electric motor unit; and A rotation sensor detects the rotation angle or rotation speed of the electric motor. The electric motor unit has: stator; A rotor, which is disposed within the stator, has a rotor shaft; and The end bracket, which is connected to the stator, provides shaft support for the output side of the rotor shaft. The motor unit of the industrial vehicle is characterized in that, The rotor shaft has a shaft portion that protrudes from the end bracket toward the output unit section. The output unit section has: The motor support body is connected to the end bracket, forming an insertion space through which the shaft can be inserted. The rotation sensor has: A sensor rotor portion, which is mounted on the shaft portion and rotates integrally with the rotor shaft; and The sensor stator is mounted on the end bracket in a manner opposite to the sensor rotor. The end bracket has a sensor storage space for accommodating the rotary sensor.

2. The motor unit for an industrial vehicle according to claim 1, characterized in that, The motor support has a fitting portion that engages with the end bracket. The end bracket has a fitted portion that engages with the fitting portion.

3. The motor unit for an industrial vehicle according to claim 2, characterized in that, The rotor shaft is perpendicular to the horizontal, and the motor support is located below the end bracket.

4. The motor unit for an industrial vehicle according to claim 3, characterized in that, The motor support has: The end face, which is opposite to the end bracket; and A protrusion that protrudes from the end face toward the end bracket side. The fitting portion is provided on the protrusion.

5. The motor unit of the industrial vehicle according to claim 2 or 3, characterized in that, It has a pad between the fitting portion and the fitted portion.

6. The motor unit of the industrial vehicle according to claim 1 or 2, characterized in that, It has a partition member that separates the insertion space from the sensor storage space.

7. The motor unit of the industrial vehicle according to claim 1 or 2, characterized in that, The rotating sensor is a resolver.

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