JP2016016717A - Hub structure with built-in motor, and bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hub structure with built-in motor capable of preventing occurrence of positional deviation in an axial direction of internal components, and to provide a bicycle therewith.SOLUTION: A hub unit 30 with built-in motor comprises a hub body 46 rotatable with respect to the hub shafts 42, 44, and a motor 48 rotating the hub body 46 inside the hub body, and the motor 48 comprises a rotor 52 penetrated by a pivot 56, and a stator 54. The housing 50 installed to the hub shaft supports rotatably the pivot 56 via a bearing 68. A push nut 120 regulating the position of one side of the rotor in a shaft direction with respect to the pivot is provided on one side of the rotor 52 in the shaft direction in the pivot 56, and a spacer 122 regulating the position of the other side of the rotor in the shaft direction with respect to the pivot is provided on the other side of the rotor in the shaft direction in the pivot. Besides, a snap ring 124 regulating the position of the pivot 56 in the shaft direction with respect to the bearing 68 is provided on the pivot 56.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a motor built-in hub structure and a bicycle.

  Patent Document 1 below discloses a structure of a hub unit for an electric wheel that includes a motor including a stator and a rotor, and a hub that houses the motor and is driven to rotate by rotation of the rotor. . In this structure, the hub is rotatably supported by the fixing support shaft. Moreover, the rotating shaft is penetrated by the center part of the circular laminated metal plate which comprises a rotor. In addition, as a structure of the hub unit for electric wheels, there exists a thing described in patent document 2, for example.

JP 2006-96059 A JP 2002-235833 A

  However, in the structure described in Patent Document 1, when a force is applied in the axial direction to the electric wheel hub unit by a fall or the like in the state of a bicycle or a single wheel provided with the electric wheel hub unit, Interference between parts may occur due to axial misalignment. In particular, in the electric wheel hub unit, since the rotating shaft is penetrated through the center of the circular laminated metal plate constituting the rotor, when the force is applied in the axial direction, the circular laminated metal plate is formed by inertial force. Easily misaligned in the axial direction with respect to the rotation axis.

  If such an internal component misalignment in the axial direction occurs, the rotational resistance increases, and as a result, it may become impossible to rotate, and there is room for improvement.

  The present invention has been made in view of the above problems, and an object thereof is to provide a hub structure with a built-in motor and a bicycle capable of suppressing the occurrence of axial displacement of internal components.

  A hub structure with a built-in motor according to a first aspect of the present invention includes a hub shaft that is fixed to a vehicle body, a hub body that is rotatably provided with respect to the hub shaft, a hub body that is provided inside the hub body, A rotor having a rotating shaft penetrated through a portion thereof, a stator that rotates the rotor, a motor that rotates the hub body, and an inner portion of the hub body that can rotate the rotating shaft via a bearing. And a housing which is attached to the hub shaft and supports the motor, and is provided on one side surface of the rotating shaft in the axial direction of the rotor, one is positioned on the side surface of the rotor and the other is the rotation A first positioning member that is configured by an annular member that holds a shaft and restricts a position of one side of the rotor in the axial direction relative to the rotary shaft; A second positioning member that restricts the position of the other side of the rotor in the axial direction with respect to the rotating shaft, and a third positioning member that is provided on the rotating shaft and restricts the position of the rotating shaft in the axial direction with respect to the bearing And having.

  In the first aspect of the present invention, the hub body is rotatably provided with respect to the hub shaft fixed to the vehicle body, and a motor for rotating the hub body is provided inside the hub body. The motor is supported by a housing attached to a hub shaft, and includes a rotor having a rotation shaft penetrating through a central portion and a stator that rotates the rotor. Further, a first positioning member is provided on one side surface of the rotor in the axial direction of the rotor, and a second positioning member is provided on the other side surface of the rotor in the axial direction of the rotor, and the housing can be rotated via a bearing. The rotating shaft supported by the second shaft is provided with a third positioning member that restricts the position of the rotating shaft in the axial direction with respect to the bearing. In such a structure, the position of one side of the rotor in the axial direction with respect to the rotation axis is regulated by the first positioning member, and the position of the other side of the rotor in the axial direction with respect to the rotation axis is regulated by the second positioning member and the third positioning member. It is restricted, and the axial displacement of the rotating shaft with respect to the bearing and the housing can be suppressed. Thereby, when a force is applied to the hub structure with a built-in motor in the axial direction, positional deviation in the axial direction of the rotor, the bearing, and the housing with respect to the rotating shaft can be suppressed.

  According to the first aspect of the present invention, the first positioning member is such that one of the annular members is positioned on the side surface of the rotor and the other of the annular members holds the rotation shaft. For this reason, it is possible to fix the 1st positioning member to the arbitrary positions of the direction of an axis of a rotating shaft according to the position of the side of a rotor. For this reason, the first positioning member can be easily attached to the rotating shaft, and the axial positioning of the rotor with respect to the rotating shaft can be performed even if each component has a variation in the axial dimension.

  According to a second aspect of the present invention, in the hub structure with a built-in motor according to the first aspect, the outer ring of the bearing is fitted to a side portion of the housing, and the second positioning member includes the bearing and the bearing. It is a spacer interposed between the rotors.

  According to the second aspect of the present invention, the outer ring of the bearing is fitted to the side portion of the housing, and the spacer as the second positioning member is interposed between the bearing and the rotor. For this reason, the clearance between the rotor and the bearing can be ensured by the spacer.

  According to a third aspect of the present invention, in the motor-integrated hub structure according to the second aspect, the third positioning member is provided on the opposite side of the rotor to the bearing against which the second positioning member abuts.

  In the invention according to claim 3, since the third positioning member is provided on the opposite side of the rotor of the bearing to which the second positioning member hits, the axial displacement of the rotating shaft and the rotor relative to the bearing and the housing is suppressed. can do.

  According to a fourth aspect of the present invention, in the motor-integrated hub structure according to any one of the first to third aspects, the hub shaft is coaxial with the rotational shaft on both sides in the axial direction of the rotational shaft. The engaging portion formed in the hub shaft is engaged with the engaged portion formed in the housing, and the hub shaft includes the housing of the hub shaft. A fourth positioning member is provided for restricting the position in the axial direction relative to.

  In a fourth aspect of the present invention, hub shafts are arranged on the both sides in the axial direction of the rotary shaft so as to be divided coaxially with the rotary shaft. Furthermore, the engaging portion formed on the hub shaft is engaged with the engaged portion formed on the housing, and the hub shaft includes a fourth positioning member that regulates the axial position of the hub shaft with respect to the housing. Is provided. Thereby, when a force is applied to the hub structure with a built-in motor in the axial direction, positional deviation in the axial direction of the hub shaft with respect to the housing can be suppressed. For this reason, it is possible to prevent the hub shaft arranged separately from the rotation shaft and the rotation shaft from interfering with each other.

  According to a fifth aspect of the present invention, in the motor built-in hub structure according to the second aspect, the rotor and the second positioning member or the bearing and the second positioning member are integrally configured.

  In the invention according to claim 5, since the rotor and the second positioning member or the bearing and the second positioning member are integrally configured, the number of parts can be reduced and the cost can be reduced.

  The invention according to claim 6 is the hub structure with built-in motor according to claim 1, wherein the first positioning member, the rotor, the second positioning member, the bearing, and the third positioning member are: These portions are arranged adjacent to each other in the axial direction of the rotating shaft, and the portion of the first positioning member that holds the rotating shaft has elasticity.

  In the sixth aspect of the present invention, the first positioning member, the rotor, the second positioning member, the bearing, and the third positioning member, each of which has a portion that holds the rotating shaft have elasticity, are arranged in the order of the rotating shaft. Arranged adjacent to each other in the axial direction, each component can be positioned more effectively in the axial direction of the rotary shaft. Moreover, since the part holding the rotating shaft of the first positioning member has elasticity, even when each component is thermally expanded due to rotation of the motor or the like, the thermal expansion of each component can be absorbed.

  According to a seventh aspect of the present invention, in the bicycle according to the seventh aspect, the front wheel or the rear wheel is provided with the motor built-in hub structure according to any one of the first to sixth aspects.

  In the invention according to claim 7, since the motor built-in hub structure according to any one of claims 1 to 6 is provided on the front wheel or the rear wheel, the motor built-in hub structure is arranged in the axial direction. When force is applied, it is possible to suppress the occurrence of misalignment of the internal components in the axial direction.

  According to the hub structure with a built-in motor and the bicycle of the present invention, it is possible to suppress the occurrence of misalignment of the internal components in the axial direction.

1 is a side view showing a bicycle to which a motor built-in hub structure according to an embodiment of the present invention is applied. It is sectional drawing which shows the motor built-in hub structure which is one Embodiment of this invention. It is an expanded sectional view which shows the structure of the rotating shaft vicinity of the rotor used for the hub structure with a built-in motor shown in FIG. It is a perspective view which shows the push nut used for the hub structure with a built-in motor shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that an arrow UP appropriately shown in the drawing indicates the upper side of the bicycle.

  FIG. 1 shows a side view of an electrically assisted bicycle 10 as a bicycle to which a motor built-in hub structure according to an embodiment of the present invention is applied.

  As shown in FIG. 1, the electrically assisted bicycle 10 includes a head pipe 12 disposed on the front side along the oblique vertical direction, and a seat pipe 14 disposed on the rear side of the head pipe 12 along the oblique vertical direction. A main pipe 16 that connects the head pipe 12 and the seat pipe 14 along the front-rear oblique direction, a motor-integrated hub unit 30 that is attached to the lower end of the front fork 18 that is connected to the lower portion of the head pipe 12, It has. The motor built-in hub unit 30 is applied with the motor built-in hub structure S1 (see FIG. 2) of the present embodiment, and is provided at the center of the front wheel 20.

  The electric assist bicycle 10 includes a chain stay 24 disposed on the rear side of the main pipe 16 and extending toward the center of the rear wheel 22, an upper end portion of the seat pipe 14, and a rear end portion of the chain stay 24. And a back hawk 26 that rotatably supports the rear wheel 22. A crank arm 28 provided with a pedal 28A is rotatably attached to the lower end of the main pipe 16.

  Further, a battery 32 and a controller 34 are mounted on the rear portion of the seat pipe 14. The electrically assisted bicycle 10 is provided with a sensor (not shown) for detecting the load on the pedal 28A at a position where the pedaling force of the pedal 28A is applied. When the load on the pedal 28A reaches a certain value, the controller 34 The controller 34 connected to the battery 32 is energized to the motor 48 (see FIG. 2) of the motor built-in hub unit 30.

  As shown in FIG. 2, the motor built-in hub unit 30 to which the motor built-in hub structure S1 is applied is a pair of left and right hub shafts 42 and 44 fixed to the lower end portion of the front fork 18 (see FIG. 1) as a vehicle body. A hub body 46 that is rotatable with respect to the hub shafts 42, 44, a motor 48 that is provided inside the hub body 46, and a housing 50 that is disposed inside the hub body 46 and supports the motor 48. And.

  The motor 48 includes a rotatable rotor 52 and a stator 54 that rotates the rotor 52. The rotor 52 is formed by laminating a plurality of circular metal plates 52A, and a rotation shaft 56 passes through the center of the circular metal plate 52A (see FIG. 3). In the present embodiment, the plurality of metal plates 52A are attached to the rotation shaft 56 by press-fitting the rotation shaft 56 into the central portion of the metal plate 52A. A plurality of permanent magnets 58 are provided in parallel to the rotation shaft 56 on the outer peripheral portion of the plurality of metal plates 52A, and S and N poles are arranged in the circumferential direction of the metal plate 52A.

  The stator 54 is formed by laminating a plurality of annular metal plates 54A. The stator 54 is fixed to the housing 50. The rotor 52 is disposed inside the stator 54 so as to be rotatable concentrically with the stator 54. More specifically, the housing 50 is configured as a pair of left and right, and includes a carrier 60 and a support body 62. The plurality of metal plates 54A constituting the stator 54 are sandwiched between the carrier 60 and the support body 62 from both sides in the axial direction of the stator 54, and tightened with a plurality of tightening bolts 64 penetrating the outer peripheral portion of the metal plate 54A. Are fixed to the carrier 60 and the support 62. The stator 54 is electrically connected to the controller 34 (see FIG. 1) via a power supply cable 66.

  The carrier 60 disposed on the left side in the width direction in FIG. 2 includes a notch 60A that is notched so as to increase the inner diameter at a position facing the metal plate 52A of the rotor 52. The outer ring of the bearing 68 is fitted into the notch 60 </ b> A of the carrier 60. The support body 62 disposed on the right side in the width direction in FIG. 2 includes a notch 62A that is notched so as to increase the inner diameter at a position facing the metal plate 52A of the rotor 52. The outer ring of the bearing 69 is fitted into the notch 62 </ b> A of the support body 62. Both ends in the axial direction of the rotary shaft 56 of the rotor 52 are rotatably supported by the bearings 68 and 69.

  In the present embodiment, the hub shaft 42 and the hub shaft 44 are separately disposed on both sides of the rotation shaft 56 in the axial direction. The hub shaft 42 and the hub shaft 44 are arranged coaxially with the rotation shaft 56. The housing 50 is attached to the hub shaft 44 on the right side in the width direction in FIG. 2, and a hub shaft support 82 described later configured integrally with the housing 50 is the hub shaft 42 on the left side in the width direction in FIG. 2. Is attached.

  A reduction device 80 that reduces the rotation of the rotor 52 and transmits it to the hub body 46 is provided outside the carrier 60 (on the side opposite to the motor 48) arranged on the left side in the width direction in FIG. The reduction gear 80 includes a hub shaft support 82 that is formed integrally with the carrier 60 (housing 50). That is, the “housing” of the present invention includes a hub shaft support 82 that is an integrally configured member. In the present embodiment, the hub shaft support 82 includes a plurality of (three in the present embodiment) leg portions extending from the outer peripheral portion of the substantially circular vertical wall portion, and a bolt is provided at the distal end side of each leg portion. It is fastened and fixed to the carrier 60 by 84.

  One end of the rotating shaft 56 in the axial direction extends outside the carrier 60. The reduction gear 80 includes a sun gear 86 formed at one end of the rotation shaft 56 in the axial direction, a plurality of (three in this embodiment) planetary gears 88 rotatably supported by the hub shaft support 82, It has. The planetary gear 88 includes a large gear 88B provided on the side of the carrier 60 in the axial direction of the shaft portion 88A, and a small gear 88C provided on the side opposite to the carrier 60 in the axial direction of the shaft portion 88A. . The large gear 88 </ b> B is meshed with the sun gear 86 of the rotation shaft 56.

  The hub body 46 surrounds the outer peripheral side of the motor 48 and the speed reducer 80, and has a substantially cup-shaped main body 90 opened on the left side (the side opposite to the motor 48) in FIG. And a cover portion 92 for covering. The cover portion 92 is fastened and fixed to the main body portion 90 by bolts 94 at a plurality of locations. An opening 90 </ b> A is formed in the bottom surface portion of the main body 90, and the bearing 100 is interposed between the inner peripheral portion of the opening 90 </ b> A of the main body 90 and the support body 62. The support body 62 is attached to a hub shaft 44 disposed on the right side in the width direction in FIG.

  An opening 92A is formed at the center of the cover 92, and a bearing 102 is interposed between the inner periphery of the opening 92A and the hub shaft 42 disposed on the left side in the width direction in FIG. . The hub body 46 is rotatably supported by the bearings 102 and 100 with respect to the left and right hub shafts 42 and 44.

  An internal gear 96 is fastened and fixed by bolts 98 on the outer peripheral side of the inside of the cover portion 92 (the reduction gear 80 side). The small gear 88 </ b> C of the planetary gear 88 is meshed with the internal gear 96.

  As shown in FIG. 3, the motor built-in hub unit 30 is attached to the rotary shaft 56 so as to be positioned on one side surface (the right side surface in FIG. 3) of the rotor 52 (metal plate 52A) in the axial direction. A push nut 120 as a first positioning member is provided. Since the push nut 120 is positioned on one side surface in the axial direction of the rotor 52 (metal plate 52 </ b> A), the position of one side in the axial direction of the rotor 52 with respect to the rotating shaft 56 is regulated. In FIG. 3, a plurality of stacked metal plates 52A are alternately displayed in white and black for easy understanding of the configuration.

  More specifically, as shown in FIG. 4, the push nut 120 is formed of an annular member, and a ring portion 120A as one of the annular members, and in a direction intersecting the radial direction radially inward from the ring portion 120A. A plurality of claw portions 120B as the other of the protruding annular members. In the push nut 120, the ring portion 120 </ b> A is positioned on one side surface of the rotor 52 (metal plate 52 </ b> A) in the axial direction, and the plurality of claw portions 120 </ b> B hold the rotating shaft 56, thereby It can be fixed at the position.

  As shown in FIG. 3, the push nut 120 is inserted into the rotating shaft 56 from the direction opposite to the protruding direction of the claw portion 120B, and is pushed in the axial direction of the rotating shaft 56, whereby the ring portion 120A is inserted into the rotor 52 ( The metal plate 52A) is positioned on one side surface in the axial direction. Accordingly, even if the push nut 120 is moved from the state shown in FIG. 3 in the protruding direction of the claw portion 120B on the rotation shaft 56 (on the right side in the axial direction of the rotation shaft 56 in FIG. 3), the plurality of claw portions 120B are It bites into (is caught by) the outer periphery of the rotating shaft 56. For this reason, the push nut 120 is prevented from coming off to the right in the axial direction of the rotary shaft 56.

  In the present embodiment, since the ring portion 120A of the push nut 120 is located on one side surface in the axial direction of the rotor 52 (metal plate 52A), one side in the axial direction of the rotor 52 (metal plate 52A) is pushed by the push nut 120. The position of is regulated. For this reason, displacement of the rotor 52 (metal plate 52A) to the right side in the axial direction of the rotation shaft 56 is suppressed. Further, the push nut 120 can be fixed at an arbitrary position in the axial direction of the rotary shaft 56, and even if the axial dimension of each component varies, the rotor 52 (metal plate 52 </ b> A) with respect to the rotary shaft 56. One side in the axial direction is positioned.

  The motor built-in hub unit 30 is a spacer 122 as a second positioning member attached to the rotary shaft 56 so as to be positioned on the other axial side surface (the left side surface in FIG. 3) of the rotor 52 (metal plate 52A). It has. In the present embodiment, the outer ring of the bearing 68 is fitted into the notch 60A of the carrier 60 (see FIG. 2), and in this state, the other side surface in the axial direction of the bearing 68 and the rotor 52 (metal plate 52A). A spacer 122 is interposed between the left side surface and the left side surface in FIG. In the present embodiment, the spacer 122 is a washer that is extrapolated to the rotating shaft 56. The spacer 122 regulates the position of the other side of the rotor 52 in the axial direction with respect to the rotating shaft 56 and secures a clearance between the rotor 52 and the bearing 68.

  A small-diameter portion 56B having a reduced outer diameter is formed at one axial end portion (end portion outside the push nut 120) of the rotating shaft 56, and a bearing 69 is provided in the small-diameter portion 56B. It has been. The rotating shaft 56 is rotatably supported by the housing 50 (see FIG. 2) via bearings 68 and 69 on both axial sides. The motor built-in hub unit 30 has a third positioning member that restricts the axial position of the rotary shaft 56 with respect to the bearing 68 on the other end side (opposite to the push nut 120) of the rotary shaft 56. A snap ring 124 is provided. In the present embodiment, a groove portion 56A is formed along the circumferential direction on the inner side in the axial direction than the sun gear 86 of the rotating shaft 56, and the snap ring 124 is engaged with the groove portion 56A. The snap ring 124 is made of, for example, a C-shaped member, and is fixed to the groove 56A by expanding in the radial direction and fitting into the groove 56A. The snap ring 124 suppresses the positional deviation in the axial direction of the rotary shaft 56 with respect to the bearing 68 and the housing 50.

  In the motor built-in hub unit 30, the push nut 120, the rotor 52, the spacer 122, the bearing 68, and the snap ring 124 are arranged adjacent to each other in the axial direction of the rotary shaft 56 in this order. Thereby, each component is positioned more effectively in the axial direction of the rotary shaft 56.

  Further, the plurality of claw portions 120B of the push nut 120 protrude in a direction intersecting with the radial direction, and the plurality of claw portions 120B of the push nut 120 (portion holding the rotating shaft 56) can be slightly deformed in the axial direction. Has elasticity. Therefore, when each component arranged around the motor 48 is thermally expanded due to rotation of the motor 48 (rotor 52) or the like, the push nut 120 absorbs the thermal expansion of each component.

  As shown in FIG. 2, the support body 62 constituting the housing 50 is formed with an opening 62 </ b> B through which the shaft portion 44 </ b> A of one (right side in FIG. 2) of the hub shaft 44 penetrates. At a position adjacent to the inner side in the axial direction from 62B, a recessed portion 62C is formed as an engaged portion that is recessed outward in the radial direction. A protruding portion 44B as an engaging portion protruding outward in the radial direction is formed at one end portion in the axial direction of the hub shaft 44 (the end portion facing the rotating shaft 56), and the protruding portion 44B is a support body. 62 is engaged with the recess 62C. A threaded portion 44C is formed on the other end portion side of the hub shaft 44 in the axial direction (the side opposite to the protruding portion 44B).

  A cylindrical portion 104 that is extrapolated to the hub shaft 44 is provided on the outer side in the axial direction of the hub shaft 44 with respect to the support body 62, so that the side portion of the cylindrical portion 104 contacts the side portion of the support body 62. Is arranged. A nut 126 as a fourth positioning member for restricting the axial position of the hub shaft 44 relative to the support body 62 (housing 50) is screwed into the screw portion 44C of the hub shaft 44. The hub shaft 44 is fixed to the support body 62 by the nut 126 being tightened to the support body 62 side via the cylindrical portion 104. That is, the nut 126 is tightened to the support body 62 side via the tubular portion 104 in a state where the protruding portion 44B of the hub shaft 44 is engaged with the recess portion 62C of the support body 62, thereby supporting the hub shaft 44. The positional deviation in the axial direction with respect to the body 62 (housing 50) is suppressed.

  Further, the hub shaft support 82 fixed integrally with the housing 50 is formed with an opening 82A through which the shaft portion 42A of the other (left side in FIG. 2) hub shaft 42 penetrates. At a position adjacent to the inner side in the axial direction from 82A, a recessed portion 82B is formed as an engaged portion that is recessed outward in the radial direction. A protruding portion 42B as an engaging portion protruding outward in the radial direction is formed at one end portion in the axial direction of the hub shaft 42 (the end portion facing the rotation shaft 56), and the protruding portion 42B is formed on the hub shaft. The support 82 is engaged with the recess 82B. A screw portion 42C is formed on the other end portion side of the hub shaft 42 in the axial direction (the side opposite to the protruding portion 42B).

  A cylindrical portion 108 that is externally inserted into the hub shaft 42 is provided outside the hub shaft support 82 in the axial direction of the hub shaft 42. A nut 126 as a fourth positioning member for restricting the axial position of the hub shaft 42 relative to the hub shaft support 82 (housing 50) is screwed into the screw portion 42C of the hub shaft 42. The hub shaft 42 is fixed to the hub shaft support 82 and the housing 50 by tightening the nut 126 to the hub shaft support 82 via the cylindrical portion 108 and the bearing 102. That is, the nut 126 is tightened to the hub shaft support 82 side via the cylindrical portion 108 and the bearing 102 in a state where the protrusion 42B of the hub shaft 42 is engaged with the recess 82B of the hub shaft support 82. Thus, the positional deviation of the hub shaft 42 in the axial direction with respect to the hub shaft support 82 and the housing 50 is suppressed.

  The hub shaft 42 and the hub shaft 44 are fixed to the lower end portion of the front fork 18 of the electric assist bicycle 10.

  On both sides in the width direction of the outer peripheral portion of the main body 90 of the hub body 46, peripheral wall portions 90B are formed along the circumferential direction. Although not shown, the spoke 21 (see FIG. 1) provided on the front wheel 20 of the electrically assisted bicycle 10 is attached to the peripheral wall portion 90B.

  Next, the operation and effect of the motor built-in hub unit 30 to which the motor built-in hub structure S1 of the present embodiment is applied will be described.

  When a load of a certain value or more acts on the depression of the pedal 28 </ b> A of the electrically assisted bicycle 10, the controller 34 energizes the stator 54 of the motor 48 from the battery 32 through the power supply cable 66. As a result, the rotor 52 rotates. Due to the rotation of the rotor 52, the sun gear 86 provided at one axial end of the rotation shaft 56 rotates, and the planetary gear 88 meshed with the sun gear 86 rotates at a fixed position. The rotation of the planetary gear 88 is decelerated and transmitted to the hub body 46 via the internal gear 96, and rotationally drives the front wheel 20 of the electric assist bicycle 10. In such a motor-integrated hub unit 30, the electric assist bicycle 10 can be caused to travel by reducing the stepping force of the pedal 28 </ b> A by the electric rotation of the rotor 52.

  Generally, in an electrically assisted bicycle equipped with a motor built-in hub unit, when an axial force is applied due to a fall or the like, the axial displacement of the components (internal components) arranged inside the motor built-in hub unit. May cause interference between parts. Even in the case of a single wheel equipped with a motor built-in hub unit, when force is applied in the axial direction, there is a possibility that interference between components may occur due to axial displacement of internal components. In particular, in a structure in which a rotating shaft is penetrated through the center of a plurality of stacked metal plates that constitute a rotor, when a force is applied in the axial direction due to overturning, the plurality of metal plates are rotated by an inertial force. It becomes easy to shift the position in the axial direction.

  In the motor-integrated hub unit 30 according to the present embodiment, as shown in FIGS. 2 and 3, the push nut 120 is provided on one axial side surface (the right side surface in FIG. 3) of the rotor 52 (metal plate 52A). It is attached to the rotating shaft 56 so as to be positioned. The push nut 120 can be fixed at an arbitrary position in the axial direction of the rotary shaft 56. That is, the push nut 120 is inserted into the rotating shaft 56 from the direction opposite to the protruding direction of the claw portion 120B, and the ring portion 120A is positioned on the side surface of the rotor 52 (metal plate 52A). Holds the rotating shaft 56. In this state, even if the push nut 120 is moved in the protruding direction of the claw portion 120B (on the right side in the axial direction of the rotation shaft 56 in FIG. 3), the plurality of claw portions 120B bite into the outer peripheral portion of the rotation shaft 56. Therefore, the push nut 120 is prevented from coming off from the rotating shaft 56.

  For this reason, the position of the axial direction one side of the rotor 52 (metal plate 52A) is regulated by the push nut 120. Therefore, when a force is applied in the axial direction due to the overturn of the electrically assisted bicycle 10 or the like, it is possible to suppress the displacement of the rotor 52 (metal plate 52A) to the right in the axial direction with respect to the rotation shaft 56. Further, the push nut 120 can be fixed at an arbitrary position in the axial direction of the rotary shaft 56, and the rotor 52 with respect to the rotary shaft 56 even if the axial dimension of each component of the hub unit 30 with built-in motor varies. One side (the right side in FIG. 3) in the axial direction of the (metal plate 52A) can be positioned.

  In the motor built-in hub unit 30, the outer ring of the bearing 68 is fitted into the notch 60A of the carrier 60 (see FIG. 2), and in this state, the other of the bearing 68 and the rotor 52 (metal plate 52A) in the axial direction. The spacer 122 is interposed between the side surface (the left side surface in FIG. 3). For this reason, the position of the other side in the axial direction of the rotor 52 with respect to the rotating shaft 56 is regulated by the spacer 122, and a clearance between the bearing 68 and the rotor 52 can be secured. In other words, since the spacer 122 is interposed between the bearing 68 and the rotor 52, it is possible to suppress the positional deviation of the rotor 52 in the axial left side with respect to the rotating shaft 56.

  The motor built-in hub unit 30 is provided with a snap ring 124 that restricts the axial position of the rotary shaft 56 relative to the bearing 68 on one end side in the axial direction of the rotary shaft 56. In the present embodiment, the snap ring 124 is engaged with the groove portion 56 </ b> A of the rotation shaft 56. The snap ring 124 is disposed so as to contact a side portion opposite to the side portion of the bearing 68 to which the spacer 122 contacts (a side portion of the bearing 68 opposite to the rotor 52). By this snap ring 124, it is possible to suppress the axial displacement of the rotating shaft 56 and the rotor 52 with respect to the bearing 68 and the housing 50.

  In such a motor-integrated hub unit 30, the push nut 120, the rotor 52, the spacer 122, the bearing 68, and the snap ring 124 are arranged adjacent to each other in the axial direction of the rotary shaft 56 in this order. . For this reason, each component can be positioned in the axial direction of the rotating shaft 56 more effectively.

  Further, the plurality of claw portions 120B of the push nut 120 protrude in a direction intersecting the radial direction, and the plurality of claw portions 120B of the push nut 120 have elasticity that can be slightly deformed in the axial direction. For this reason, even when each component of the motor built-in hub unit 30 is thermally expanded due to rotation of the motor 48 or the like, the thermal expansion of each component can be absorbed by the push nut 120.

  In the motor built-in hub unit 30, the protruding portion 44 </ b> B of the hub shaft 44 is engaged with the recessed portion 62 </ b> C of the support body 62 constituting the housing 50. In this state, the nut 126 screwed into the screw portion 44C of the hub shaft 44 is tightened to the support body 62 side via the cylindrical portion 104, whereby the hub shaft 44 is fixed to the support body 62. Yes. That is, the protruding portion 44B of the hub shaft 44 is engaged with the recessed portion 62C of the support body 62, and the nut 126 is connected to the support body 62 side through the tubular portion 104 from the opposite side of the hub shaft 44 in the axial direction. By being tightened, the axial position of the hub shaft 44 with respect to the support body 62 (housing 50) is regulated. For this reason, the nut 126 can suppress displacement of the hub shaft 44 in the axial direction with respect to the housing 50. Therefore, even if the rotating shaft 56 and the hub shaft 44 are arranged separately, the hub shaft 44 and the rotating shaft 56 can be prevented from interfering with each other.

  Further, the protruding portion 42 </ b> B of the hub shaft 42 is engaged with the recess 82 </ b> B of the hub shaft support 82 fixed integrally with the housing 50. In this state, the nut 126 screwed into the screw portion 42C of the hub shaft 42 is tightened to the hub shaft support 82 side via the cylindrical portion 108 and the bearing 102, so that the hub shaft 42 is connected to the hub shaft 42. It is fixed to the support body 82 and the housing 50. In other words, the protrusion 42B of the hub shaft 42 is engaged with the recess 82B of the hub shaft support 82, and the nut 126 is inserted from the opposite side of the hub shaft 42 in the axial direction via the cylindrical portion 108 and the bearing 102. By being tightened to the hub shaft support 82 side, the axial position of the hub shaft 42 with respect to the hub shaft support 82 and the housing 50 is regulated. For this reason, the axial displacement of the hub shaft 42 with respect to the hub shaft support 82 and the housing 50 can be suppressed by the nut 126. Therefore, even if the rotating shaft 56 and the hub shaft 42 are arranged separately, the hub shaft 42 and the rotating shaft 56 can be prevented from interfering with each other.

  Further, the lower end portion of the front fork 18 is fastened and fixed to the hub shaft 42 and the hub shaft 44 with a nut 126 and a hub nut (not shown) sandwiched therebetween. At this time, if the nut 126 is not provided, the hub shaft 42 and the hub shaft 44 are attracted to the outside in the axial direction by tightening the hub nut, and the other components of the built-in motor hub unit 30 are also affected by deformation or the like. This causes an increase in resistance. However, by providing the nut 126, the fixing force of the hub nut that fixes the front fork 18 acts only between the nut 126 and the hub nut, and does not affect other components, so that good rotation can be maintained. .

In the present embodiment, the rotor 52 and the spacer 122 as the second positioning member are configured by separate members, but the present invention is not limited to this configuration. For example, the rotor 52 (the metal plate 52 </ b> A) and the second positioning member may be integrally configured, and the second positioning member may be disposed on the side surface of the bearing 68. As a case where the rotor 52 (metal plate 52A) and the second positioning member are configured integrally, in addition to a case where the rotor 52 (metal plate 52A) is configured by one component, two components may be integrated by bonding or the like. Thereby, the number of parts can be reduced and the cost can be reduced.
Instead of integrally configuring the rotor 52 (metal plate 52A) and the second positioning member, the bearing 68 and the second positioning member are configured integrally, and the second positioning member is used as a side surface of the rotor 52. You may arrange | position so that it may be located in.

  In the present embodiment, the spacer 122 as the second positioning member is interposed between the bearing 68 and the rotor 52, but the present invention is not limited to this configuration. When the second positioning member is not interposed between the bearing 68 and the rotor 52, the second positioning member is configured by a snap ring or the like engaged with the groove portion of the rotating shaft 56, and the other axial direction of the rotor 52 is It is preferable to contact the side surface. Accordingly, the position of the other side of the rotor 52 in the axial direction of the rotor 52 with respect to the rotation shaft 56 can be restricted by the second positioning member, and the positional deviation of the rotor 52 relative to the rotation shaft 56 can be suppressed.

  Further, the push nut 120 as the first positioning member and the snap ring 124 as the third positioning member are not limited to the configuration of the present embodiment, and can be changed to positioning members of other structures.

  Further, in the motor built-in hub unit 30 according to the present embodiment, the rotating shaft 56 and the left and right hub shafts 42 and 44 are divided in the axial direction, but the present invention is not limited to this configuration. Absent.

  Furthermore, the motor built-in hub unit 30 of the present embodiment is provided on the front wheel 20 of the electrically assisted bicycle 10, but the present invention is not limited to this configuration. For example, a motor-integrated hub unit may be provided on the rear wheel of the electrically assisted bicycle.

10 Electric assist bicycle (bicycle)
18 Front Hawk (Body)
20 Front wheel 22 Rear wheel 30 Motor built-in hub unit 42 Hub shaft 42B Protruding part (engaging part)
44 Hub shaft 44B Protruding part (engaging part)
46 Hub body 48 Motor 50 Housing 52 Rotor 54 Stator 56 Rotating shaft 60 Carrier (housing)
60A Notch (part where the bearing is fitted)
62 Support (housing)
62C hollow (engaged part)
68 Bearing 69 Bearing 82 Hub shaft support body (integrated with housing)
82B hollow (engaged part)
120 Push nut (first positioning member)
120A Ring part (one of the annular members)
120B Claw (the other of the annular member)
122 Spacer (second positioning member)
124 Snap ring (third positioning member)
126 Nut (fourth positioning member)
S1 Hub structure with built-in motor

Claims (7)

A hub axle fixed to the vehicle body,
A hub body rotatably provided with respect to the hub shaft;
A motor provided inside the hub body, the rotor having a rotation shaft penetrating through a central portion thereof, a stator for rotating the rotor, and a motor for rotating the hub body;
A housing provided inside the hub body, rotatably supporting the rotating shaft via a bearing, attached to the hub shaft and supporting the motor;
The rotary shaft is provided on one side surface of the rotor in the axial direction, one is located on the side surface of the rotor, and the other is an annular member that holds the rotary shaft, and one of the rotor axial directions with respect to the rotary shaft A first positioning member for regulating the position on the side;
A second positioning member that is provided on the other side surface of the rotor in the axial direction of the rotor and restricts the position of the rotor on the other side in the axial direction of the rotor;
A third positioning member that is provided on the rotating shaft and restricts the position of the rotating shaft in the axial direction with respect to the bearing;
Motor built-in hub structure. The outer ring of the bearing is fitted to the side of the housing,
The motor built-in hub structure according to claim 1, wherein the second positioning member is a spacer interposed between the bearing and the rotor.   The hub structure with a built-in motor according to claim 2, wherein the third positioning member is provided on a side opposite to the rotor of the bearing to which the second positioning member hits. The hub shaft is arranged on the both sides in the axial direction of the rotating shaft and is coaxially divided with the rotating shaft,
The engaging portion formed on the hub shaft is engaged with the engaged portion formed on the housing,
The hub structure with a built-in motor according to any one of claims 1 to 3, wherein the hub shaft is provided with a fourth positioning member that regulates an axial position of the hub shaft with respect to the housing.   The hub structure with a built-in motor according to claim 2, wherein the rotor and the second positioning member or the bearing and the second positioning member are integrally formed. The first positioning member, the rotor, the second positioning member, the bearing, and the third positioning member are arranged adjacent to each other in the axial direction of the rotating shaft in these order,
The hub structure with a built-in motor according to claim 1, wherein a portion of the first positioning member that holds the rotating shaft has elasticity.   A bicycle in which the front wheel or the rear wheel is provided with the motor-integrated hub structure according to any one of claims 1 to 6.

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