WO2018173696A1 - Power unit for electric vehicle - Google Patents

Power unit for electric vehicle Download PDF

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Publication number
WO2018173696A1
WO2018173696A1 PCT/JP2018/008022 JP2018008022W WO2018173696A1 WO 2018173696 A1 WO2018173696 A1 WO 2018173696A1 JP 2018008022 W JP2018008022 W JP 2018008022W WO 2018173696 A1 WO2018173696 A1 WO 2018173696A1
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WO
WIPO (PCT)
Prior art keywords
reduction
ring gear
gear
hub
case
Prior art date
Application number
PCT/JP2018/008022
Other languages
French (fr)
Japanese (ja)
Inventor
宣人 武藤
利記 小久保
Original Assignee
武蔵精密工業株式会社
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Publication date
Application filed by 武蔵精密工業株式会社 filed Critical 武蔵精密工業株式会社
Publication of WO2018173696A1 publication Critical patent/WO2018173696A1/en

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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/64—Electric machine technologies in electromobility

Definitions

  • the present invention relates to an electric motor in which a motor and a speed reduction mechanism that decelerates the driving force of the motor and transmits it to the hub case are accommodated side by side in an axial direction in a vehicle, particularly a wheel hub case rotatably supported by a hub shaft.
  • the present invention relates to a vehicle power unit.
  • axial direction and radial direction refer to an axial direction and a radial direction based on the hub axis, respectively.
  • a speed reduction mechanism portion including a planetary gear mechanism is provided.
  • a speed reduction sun gear that is rotationally driven by a motor, a speed reduction carrier that rotatably supports a speed reduction planetary gear meshing with the speed reduction sun gear, and a bottomed cylindrical shape
  • a reduction ring gear that is fixed to the open end of the motor case (first case member 32) and meshes with the reduction planetary gear, and the closed end of the motor case is fixed to and supported by the hub axle.
  • the reduction ring gear is fixed to the free end portion (that is, the open end portion) of the motor case that is separated in the axial direction from the support point (that is, the closed end portion) to the hub shaft.
  • the reduction ring gear is supported in a cantilever manner. Therefore, the reduction ring gear is likely to vibrate due to the rotational vibration of the motor, and the vibration may cause problems such as poor contact of the meshing portion between the reduction ring gear and the reduction planetary gear, uneven wear, and noise generation due to meshing. there were.
  • the present invention has been made in view of such circumstances, and for an electric vehicle capable of solving the above-mentioned problem by ensuring that the reduction ring gear can be stably and firmly supported on the hub case while ensuring a high reduction ratio in the reduction mechanism.
  • An object is to provide a power unit.
  • one end wall portion and the other end wall portion of a hub case of a wheel are rotatably supported by a hub shaft, and a motor and a driving force of the motor are provided to the hub case.
  • a speed reduction mechanism that decelerates and transmits to the hub case is housed side by side in the axial direction, and the motor has a bottomed cylindrical motor case that is open at one end and faces the one end wall of the hub case.
  • the other end portion which becomes the bottom wall of the motor case is a power unit for an electric vehicle fixed and supported on the hub shaft
  • the speed reduction mechanism portion includes a speed reduction sun gear which is rotationally driven by the motor, A first gear that meshes with the reduction sun gear, a speed reduction carrier that rotatably supports a second gear arranged coaxially with the first gear, and meshed with the first gear by being fitted to the one end portion of the motor case
  • a first feature is that a bearing that is rotatably supported by the actuator is interposed.
  • the two side walls of the speed reduction carrier that sandwich the first and second gears in the axial direction are rotatably supported by the hub shaft.
  • the first reduction ring gear integrally has a ring gear extending portion extending in the axial direction from the one end portion of the motor case to the outside of the motor case.
  • the third feature is that the outer peripheral surface or inner peripheral surface of the extending portion is the mounting surface of the bearing on the first reduction ring gear side.
  • the planetary gear of the speed reduction mechanism portion formed by the planetary gear mechanism has the coaxial first and second gears, and the first reduction ring gear meshing with the first gear has a bottomed cylindrical shape.
  • a second reduction ring gear that fits to one end (open end) of the motor case and meshes with the second gear is provided in the hub case, and the first reduction ring gear rotates to the hub case between the first reduction ring gear and the hub case. Since the bearing to be freely supported is interposed, the support rigidity of the first and second reduction ring gears can be increased while ensuring a high reduction ratio in the reduction mechanism.
  • the first reduction ring gear is fixed to the free end (one end) of the motor case and is in a cantilevered form with respect to the hub shaft.
  • the first reduction ring gear is connected to the hub case via a bearing. Since the first reduction ring gear is substantially supported by both ends, the support is stable and effective in preventing shaft misalignment. As a result, even if the rotational vibration of the motor is directly transmitted to the first reduction ring gear, the vibration of the first reduction ring gear can be effectively suppressed. Therefore, the contact of the meshing portion between the first reduction ring gear and the reduction planetary gear is good. Thus, the durability can be enhanced and the generation of noise from the meshing portion can be reduced.
  • both side wall portions of the speed reduction carrier sandwiching the first and second gears in the axial direction are rotatably supported on the hub shaft, so that the open end portion (one end of the motor case) Part) is supported on the hub case side through the first reduction ring gear and the bearing, and the reduction carrier can be supported at both ends with a long support span in the axial direction by utilizing the space generated around the hub shaft. .
  • the speed reduction carrier can be stably supported while reducing the size of the power unit.
  • the first reduction ring gear integrally has a ring gear extending portion extending axially out of the motor case from one end portion of the motor case. Since the outer peripheral surface or inner peripheral surface is the mounting surface on the first reduction ring gear side of the bearing, it is possible to easily secure the bearing diameter without specially increasing the motor case diameter, and further reducing the size of the power unit It can contribute to the conversion.
  • FIG. 1 is an overall longitudinal sectional view of a power unit for a battery-assisted bicycle according to a first embodiment of the present invention.
  • FIG. 2 is an enlarged view taken along the arrow 2 in FIG.
  • First embodiment 3 is an enlarged view taken along the line 3 in FIG. 1 (a cross-sectional view taken along line 3-3 in FIG. 4).
  • First embodiment 4 shows the locked state of the transmission sun gear with respect to the hub shaft.
  • FIG. 4 (A) is a sectional view taken along line 4A-4A in FIG. 3
  • FIG. 4 (B) is a sectional view taken along line 4B-4B in FIG. It is.
  • (First embodiment) 5A and 5B show the unlocked state of the transmission sun gear with respect to the hub shaft.
  • FIG. 1 is an overall longitudinal sectional view of a power unit for a battery-assisted bicycle according to a first embodiment of the present invention.
  • FIG. 2 is an enlarged view taken along the arrow 2 in FIG.
  • First embodiment 3 is an
  • FIG. 5A is a diagram corresponding to FIG. 4A
  • FIG. 5B is a diagram corresponding to FIG. It is.
  • FIG. 6 is a view corresponding to FIG. 2 showing a second embodiment of the present invention.
  • FIG. 7 is a view corresponding to FIGS. 2 and 6 showing a third embodiment of the present invention.
  • hird embodiment is a view corresponding to FIGS. 2 and 6 showing a third embodiment of the present invention.
  • An electric assist bicycle power unit U which is an example of an electric vehicle power unit, includes a single hub shaft 11 that functions as a wheel of an electric bicycle, for example, a rear wheel axle, and a hub shaft that functions as a hub portion of a rear wheel. 11, a hub case H that is rotatably supported by the motor 11, a transmission mechanism T that is housed in the hub case H and that transmits a pedaling force input from a pedal to the hub case H so as to be capable of shifting, and the transmission mechanism T in the hub case H And a motor drive system MD that is adjacently disposed in the axial direction and can drive the hub case H electrically.
  • the hub shaft 11 is formed as an integral shaft by forging or machining. Although not shown, both end portions of the hub shaft 11 are inserted and supported by the left and right rear forks, and are coupled and fixed by fastening means such as nuts, as in a conventionally known electric bicycle.
  • the hub case H has a bottomed cylindrical hub case body Hm having one end opened and an end wall Hmb integrally formed at the other end, and an annular end detachably coupled to the opened one end Hme of the hub case body Hm.
  • a wall member He He.
  • the end wall member He has a first end so as to surround the first end wall member half He1 and the first end wall member half He1, for example.
  • the second end wall member half body He ⁇ b> 2 is fitted and fixed to the outer peripheral portion of the wall member half body He ⁇ b> 1.
  • the outer peripheral portion of the second end wall member half body He2 is inlay-fitted to one end portion Hme of the hub case main body Hm.
  • the first and second end wall member halves He1 and He2 may be coupled to each other by an appropriate coupling means, for example, press fitting, welding, screwing, or the like, or may be integrally formed.
  • the coupling means of the end wall member He to the hub case main body Hm penetrates the end wall member He (more specifically, the second end wall member half body He2), and the outer periphery of the one end Hme of the hub case main body Hm.
  • the end wall member He more specifically, the second end wall member half body He2
  • the outer periphery of the one end Hme of the hub case main body Hm can also be adopted.
  • a rear wheel spoke (not shown) is fixed to the outer periphery of the hub case body Hm.
  • the end wall Hmb of the hub case H is rotatably supported by the hub shaft 11 via the hub supporting first bearing B1 and the end wall member He via the hub supporting second bearing B2.
  • a hub support ring 15r that holds the hub support first bearing B1 between the inner periphery of the end wall portion Hmb and the hub shaft 11 is supported via a support nut 15n. Is done.
  • the support nut 15n fits and supports the inner peripheral portion of the hub support ring 15r.
  • the support nut 15n is screwed to the hub shaft 11, and the screwed position is fixed by the lock nut 16.
  • the hub shaft 11 has a transmission carrier of the transmission mechanism T that holds the hub supporting second bearing B2 between the inner periphery of the end wall member He (more specifically, the first end wall member half body He1). 22 is rotatably supported via a carrier support bearing B3 as will be described later.
  • the hub supporting first and second bearings B1 and B2 are arranged on the radially inner side of the outer diameter of the motor drive system MD (and therefore the motor M) when viewed in a projection plane orthogonal to the hub shaft 11.
  • the transmission mechanism T includes a driven sprocket 21 as an input member to which a pedaling force from a pedal is input, a transmission carrier 22 that is coupled to the driven sprocket 21 so as to rotate integrally with the driven sprocket 21, and can rotate on the hub shaft 11.
  • the transmission sun gear 23 is rotatably fitted and supported on the outer periphery of the motor 11, and is interposed between the transmission sun gear 23 and the hub shaft 11 so that the transmission sun gear 23 can be switched between a fixed state and a rotatable state on the hub shaft 11.
  • the pedal force input to the speed change carrier 22 is transferred to the hub case via the speed change planetary gear 24 and the speed change ring gear 25.
  • the pedal treading force is transmitted as a rotational force to the driven sprocket 21 through a chain transmission mechanism including the driven sprocket 21, and the rotational force is transmitted to the transmission carrier 22 and further transmitted to the hub case H through the transmission mechanism T. To drive the rear wheels.
  • the transmission carrier 22 is divided into, for example, a cylindrical first carrier half body 22A and a disk-shaped second carrier half body 22B in order to facilitate manufacturing.
  • One end 22Aa of the first carrier half 22A integrally has a carrier shaft support wall that supports both ends of the carrier shaft 27, whereby the one end 22Aa is connected to the carrier shaft 27 and the variable planetary gear 24. And supported by the hub shaft 11 via the transmission sun gear 23.
  • the carrier support bearing B3 between the inner periphery of the other end 22Ab of the first carrier half body 22A and the outer periphery of the stopper ring 17 that is non-rotatably fitted (for example, press-fitted) to the outer periphery of the hub shaft 11, the carrier support bearing B3.
  • the other end 22Ab is rotatably supported by the hub shaft 11 via the carrier supporting bearing B3.
  • each inner peripheral portion of the driven sprocket 21 adjacent to the second carrier half 22B is spline fitted to the outer periphery of the first carrier half 22A, and is fixed by a washer 28 and a retaining ring 29.
  • first and second carrier halves 22A and 22B may be coupled to each other by other suitable coupling means such as welding, screwing, bonding, or the like, or may be integrally formed.
  • a cylindrical carrier extension 22Ba extending toward the motor M is integrally formed on the axial inner side surface of the outer peripheral portion of the second carrier half 22B, and the carrier extension 22Ba is more than the transmission ring gear 25. It is formed in a large diameter cylindrical shape. Between the outer peripheral surface of the carrier extension portion 22Ba and the opposed peripheral surface between the inner periphery of the end wall member He (more specifically, the second end wall member half body He2), the above-described second bearing for hub support is provided. B2 is interposed.
  • the transmission ring gear 25 is integrally formed with a ring gear main body portion 25m having an inner tooth 25mg that meshes with the transmission planetary gear 24, and a ring gear extending portion 25a extending from the ring gear main body portion 25m in the opposite direction to the motor drive system MD in the axial direction.
  • the ring gear extension 25a is concentrically surrounded by the carrier extension 22Ba. Between the inner circumference of the ring gear extension 25a and the outer circumference of the transmission carrier 22 (more specifically, the one end 22Aa of the first carrier half 22A), a transmission ring gear support bearing B4 is interposed. .
  • the one-way transmission mechanism OT is provided between the transmission ring gear 25 and the end wall member He, and can transmit power from the transmission ring gear 25 only to the end wall member He side, and the first one-way clutch C1. Is provided between the speed change carrier 22 and the speed change ring gear 25 at a position shifted in the axial direction, and includes a second one-way clutch C2 capable of transmitting power only from the speed change carrier 22 to the speed change ring gear 25.
  • the first one-way clutch C1 is interposed between the opposed peripheral surfaces of the outer periphery of the ring gear main body portion 25m and the inner peripheral boss portion 63 of the first end wall member half body He1, and the second one-way clutch.
  • C2 is interposed between opposing peripheral surfaces of the inner periphery of the carrier extension portion 22Ba and the outer periphery of the ring gear extension portion 25a.
  • At least a part (most part in the present embodiment) of the second one-way clutch C2 and at least a part (all in the present embodiment) of the transmission ring gear support bearing B4 are in the same position in the axial direction. That is, the arrangement is overlapped in the radial direction. Further, at least a part (all in this embodiment) of the second one-way clutch C2 and at least a part (most part in the present embodiment) of the second hub supporting bearing B2 are in the same position in the axial direction, that is, the diameter. It is an arrangement that overlaps in the direction.
  • the first and second one-way clutches C1 and C2 have the same structure as a conventionally well-known one-way clutch structure, and although not shown, for example, any one of the opposing circumferential surfaces of the inner race and the outer race A plurality of engagement grooves provided at intervals on one peripheral surface, and an engaging member (for example, a ratchet claw) that is pivotally supported on one of the other peripheral surfaces so as to be able to engage with and disengage from the engagement groove. And a spring that repels each engaging element in a locking direction with the engaging groove.
  • the inner race and the outer race may be separated from the members provided with the first and second one-way clutches C1 and C2, may be retrofitted, or may be formed integrally.
  • the outer peripheral surfaces of the ring gear main body portion 25m and the ring gear extending portion 25a which are the attachment surfaces of the first and second one-way clutches C1 and C2 in the transmission ring gear 25, have the same diameter.
  • the inner peripheral surface of the inner peripheral boss 63 of the first end wall member half body He1 serving as the mounting surface of the first one-way clutch C1 in the end wall member He and the mounting surface of the second one-way clutch C2 in the transmission carrier 22 are provided.
  • the inner peripheral surface of the carrier extension 22Ba has the same diameter. Accordingly, the first and second one-way clutches C1 and C2 can use parts having the same specifications, and cost savings can be achieved by sharing parts.
  • the circumferential direction of the engagement element and the engagement groove in the first one-way clutch C1 is the same as that of the second one-way clutch C2. They are set in opposite directions.
  • the shift mechanism S includes a plurality of ratchet grooves 23 a that are recessed in the circumferential direction on the inner circumferential surface of the transmission sun gear 23, and a plurality that are recessed in the circumferential direction on the outer circumferential surface of the hub shaft 11.
  • the claw 41 is fitted in the outer periphery of the hub shaft 11 in an elastically contracted state and pressed against the outer periphery of the intermediate portion 41m of the ratchet claw 41 so as to constantly urge the claw 41 in the engagement direction with the ratchet groove 23a (that is, the standing direction of the ratchet claw 41).
  • the ring spring 42 and a recess 431i in which the tip portion 41bs of the base end portion 41b of the ratchet pawl 41 can protrude and retract are provided on the inner peripheral surface and can be rotated between a predetermined lock position and an unlock position. Then, the operation drum 43 fitted and supported on the outer periphery of the hub shaft 11 and the movable end 44a is provided on the operation drum 43 so as to urge the operation drum 43 to the unlock position (namely, the position of FIG. 5B).
  • the operation drum 43 is divided into first and second drum halves 431 and 432 that are connected to each other so as not to rotate relative to each other (for example, meshing and coupling). From the outer end of the second drum half 432, a plurality of operating rod portions 432t arranged at intervals in the circumferential direction of the operating drum 43 are integrally extended outward in the axial direction. Each operation lever 432t protrudes outwardly from the speed change carrier 22 through the insertion grooves formed in the inner peripheral surfaces of the fixing ring 46 and the stopper ring 17 respectively. The operation lever 432t can rotate the operation drum 43 between a lock position and an unlock position by an operation unit CU described later.
  • the ratchet pawl 41 released from the operation drum 43 is based on the biasing force of the ring spring 42. Since the state is switched to the latched state in the ratchet groove 23a, the transmission sun gear 23 is connected to the hub shaft 11, that is, in a fixed state and cannot be rotated. As a result, the speed change planetary gear 24 meshed with the speed change sun gear 23 revolves around the speed change carrier shaft 27 while revolving around the hub shaft 11 as the speed change carrier 22 rotates, so that the speed change planet 22 rotates.
  • the speed is increased at 24 and transmitted to the transmission ring gear 25, and the increased rotation of the transmission ring gear 25 is transmitted to the end wall member He and thus to the hub case H via the second one-way clutch C ⁇ b> 2.
  • the second speed increased from the first speed in the transmission mechanism T is established.
  • a unit case CUc of an operation unit CU for switching the shift mechanism S is fixed to the outer periphery of the hub shaft 11 by a nut 18 at a position adjacent to the outer side in the axial direction of the transmission carrier 22.
  • an operation plate 71 that can engage with the operation lever portion 432t of the shift mechanism S and can rotate the operation drum 43 is accommodated and supported in a rotatable manner.
  • the operation plate 71 is connected to an operation lever 72 that protrudes outside the unit case CUc and can rotate the operation plate 71.
  • the operation lever 72 can be remotely operated from the outside. Therefore, the occupant can operate the operation unit CU by hand operation, and by selectively switching the operation drum 43 of the shift mechanism S to either the lock position or the unlock position based on the operation input, the first operation described above is performed.
  • the speed change operation between the second speed and the second speed can be arbitrarily performed.
  • the motor drive system MD includes an electric motor M and a speed reduction mechanism R that decelerates the driving force of the motor M and transmits it to the end wall member He of the hub case H.
  • the motor M includes, for example, a bottomed cylindrical motor case 31 that is open at one end 31 a and faces the end wall member He, a stator 32 that is fixed to the inner peripheral surface of the body portion of the motor case 31, and the radial direction of the stator 32.
  • a rotor 33 with a permanent magnet disposed on the inner side and a cylindrical motor shaft 34 for fixing the rotor 33 to the outer peripheral portion are provided.
  • the motor shaft 34 is rotatably fitted and supported on the outer periphery of the hub shaft 11 via a pair of motor shaft support first and second bearings B5 and B5 '.
  • a boss-like inner peripheral portion of the end wall portion 31b that becomes the bottom wall of the motor case 31 is fitted and fixed to the outer periphery of a boss member 35 that is fitted and fixed to the outer periphery of the hub shaft 11 (press-fit in this embodiment), for example.
  • a fixing means for example, combined use of a spline and a retaining ring, screwing or the like
  • an electronic control unit ECU for controlling energization to the motor M (more specifically, the coil portion of the stator 32) is attached.
  • the wiring extending from the electronic control unit ECU is drawn out through the through hole of the hub support ring 15r. Note that the wiring is connected to a pedaling force detection means, an in-vehicle battery or the like (not shown).
  • the reduction mechanism R integrally couples a reduction sun gear 51 that is rotationally driven by the motor M, a first gear 52a that meshes with the reduction sun gear 51, and a second gear 52b that is arranged coaxially with the first gear 52a.
  • a second reduction ring gear 55 that meshes with the second gear 52b.
  • the reduction sun gear 51 is press-fitted and fixed to the outer periphery of the hub shaft 11 adjacent to a reduction carrier supporting first bearing B6 described later.
  • a fixing means of the reduction sun gear 51 a fixing means different from the present embodiment, for example, welding, caulking, adhesion, spline fitting, and a combined use of a retaining ring may be employed.
  • the reduction carrier 53 includes a reduction carrier shaft 56 that rotatably penetrates and supports each reduction planetary gear 52, a first carrier half 53a having a first side wall portion s1 that fixes one end of the reduction carrier shaft 56, and A second carrier half 53b having a second side wall portion s2 that sandwiches the reduction planetary gear 52 between the first side wall portion s1 and fixes the other end portion of the reduction carrier shaft 56;
  • the first carrier half 53a integrally has a plurality of connecting arm portions 53au, and the tip of the connecting arm portion 53au is fixed to the second carrier half 53b.
  • the first side wall portion s1 is connected to the motor shaft 34 (and thus via the motor shaft 34) via the first carrier B6 for speed reduction carrier support interposed between the inner periphery of the first carrier half 53a and the opposed peripheral surface of the motor shaft 34.
  • the hub shaft 11) is rotatably supported.
  • the second side wall portion s2 is rotatable on the hub shaft 11 via the second carrier B6 ′ for supporting the speed reduction carrier interposed between the inner periphery of the second carrier half 53b and the opposed peripheral surface of the hub shaft 11. Supported.
  • a fixing ring 57 for engaging the inner race of the second bearing B 6 ′ for supporting the deceleration carrier and holding the second bearing B 6 ′ (and hence the deceleration carrier 53) on the hub shaft 11. Is inserted (for example, press-fitted).
  • the first reduction ring gear 54 is integrally formed with a ring gear main body portion 54m having an inner tooth 54mg that meshes with the first gear 52a and a ring gear extension portion 54a that extends from the ring gear main body portion 54m to the outside of the motor case 31 in the axial direction.
  • a ring gear main body portion 54m having an inner tooth 54mg that meshes with the first gear 52a and a ring gear extension portion 54a that extends from the ring gear main body portion 54m to the outside of the motor case 31 in the axial direction.
  • the first reduction ring gear 54 is rotated via the hub case H (more specifically, the second end wall member half body He2).
  • a first reduction ring gear support bearing B7 to be freely supported is interposed. Accordingly, the inner peripheral surface of the ring gear extending portion 54a becomes the mounting surface on the first reduction ring gear 54 side of the bearing B7.
  • the first reduction ring gear 54 is fixed to the motor case 31.
  • the reduction planetary gear 52 supported so as to rotate freely rotates around the reduction carrier shaft 56 while revolving around the hub shaft 11. Then, the revolution and rotation of the reduction planetary gear 52 are transmitted from the second gear 52b to the second reduction ring gear 55, so that the rotation of the drive electric motor 4 is transmitted to the hub case H at a high reduction ratio, as will be described later. It becomes possible.
  • the second one-way clutch C2 is interposed between the transmission carrier 22 and the transmission ring gear 25, and the first one-way clutch C1 is interposed between the transmission ring gear 25 and the end wall member He. Even when the pedal rotation is slow and the hub case H is fast, the rotation of the hub case H is not transmitted to the pedal side.
  • the motor M is energized from the electronic control unit ECU, and the rotation of the motor shaft 34 causes the speed reduction mechanism R to be After that, it is sufficiently decelerated and transmitted to the end wall member He and therefore to the hub case H.
  • insufficient pedaling force is assisted by the driving force of the motor M, so that it is possible to travel without difficulty even on an uphill.
  • the first one-way clutch C1 interposed between the end wall member He and the transmission ring gear 25, and the second one-way clutch C2 interposed between the transmission ring gear 25 and the transmission carrier 22; are arranged in series on the transmission ring gear 25 (more specifically, the outer peripheral surfaces of the transmission ring gear main body 25m and the ring gear extension 25a) at positions shifted in the axial direction, and further between the transmission carrier 22 and the end wall member He.
  • the second bearing B2 for supporting the hub interposed between the second one-way clutch C2 and the second one-way clutch C2 is positioned so as to be in the same position in the axial direction (that is, overlaps in the radial direction) with the majority of the second one-way clutch C2.
  • the transmission mechanism T is reduced in the axial direction compared to the conventional structure in which the first and second one-way clutches C1 and C2 and the hub supporting second bearing B2 are arranged in the axial direction. Miniaturization of the power unit U is achieved.
  • the first and second one-way clutches C1 and C2 are arranged in series on the transmission ring gear 25 as described above, while one end wall portion of the hub case H, that is, the end wall member He is provided from the motor drive system MD.
  • a driven portion to which power is input (more specifically, the inner extending portion 62 of the second end wall member half body He2) is provided.
  • the driven portion from which the end wall member He receives power includes the driven portion from the motor drive system MD (the inner extending portion 62 of the second end wall member half body He2) and the driven portion from the first one-way clutch C1.
  • the transmission ring gear 25 includes a ring gear main body portion 25m having an inner tooth 25mg meshing with the transmission planetary gear 24, and a ring gear extending portion 25a extending axially outward from the ring gear main body portion 25m.
  • the clutch C2 is interposed between the outer periphery of the ring gear extension 25a and the inner periphery of the carrier extension 22Ba.
  • a transmission ring gear support bearing B4 is interposed between the inner periphery of the ring gear extension 25a and the opposed peripheral surface of the transmission carrier 22, and this transmission ring gear support bearing B4 is a large one of the second one-way clutch C2. Arranged in the same position in the axial direction as the part.
  • the transmission ring gear 25 is stably supported on the transmission carrier 22 via the transmission ring gear support bearing B4 even if the transmission ring gear 25 becomes longer in the axial direction due to the series arrangement of the first and second one-way clutches C1 and C2. Therefore, the tooth contact with the speed change planetary gear 24 is good, and the speed change planetary gear 24 can rotate smoothly and quietly.
  • the transmission ring gear support bearing B4 since the transmission ring gear support bearing B4 partially overlaps the ring gear extension 25a in the radial direction, the axial extension of the bearing B4 is suppressed, so that the power unit U can be downsized in the axial direction. It is done.
  • the reduction planetary gear 52 has first and second gears 52a and 52b arranged coaxially, and the first reduction ring gear 54 meshed with the first gear 52a is a bottomed cylinder.
  • the second reduction ring gear 55 fitted to the one end 31a of the motor case 31 and meshed with the second gear 52b is connected to the end wall member He (more specifically, the inner extension of the second end wall member half He2). 62, and a first reduction ring gear support bearing B7 is provided between the first reduction ring gear 54 and the end wall member He (more specifically, the outer periphery of the inner extension 62). Intervened.
  • the speed reduction mechanism R has sufficient support rigidity of the first and second speed reduction ring gears 54 and 55 for securing the speed reduction ratio while ensuring a high speed reduction ratio by utilizing the end wall member He. It can be secured.
  • the first reduction ring gear 54 is fixed to one end 31 a of the motor case 31, that is, a free end (open end), and is in a cantilevered form with respect to the hub shaft 11.
  • the ring gear extension 54a of the reduction ring gear 54 is supported by the end wall member He via the first reduction ring gear support bearing B7, so that the first reduction ring gear 54 is supported in a substantially doubly supported form. Is stable and effective in preventing shaft misalignment. Therefore, even if the rotational vibration of the motor M is directly transmitted to the first reduction ring gear 54, the vibration of the first reduction ring gear 54 can be suppressed as much as possible. Therefore, the first reduction ring gear 54 and the reduction planetary gear 52 (more specifically, the first reduction ring gear 54). It is possible to improve the durability by making the contact of the meshing portion with the 1 gear 52a) good, and to reduce the generation of noise from the meshing portion.
  • the one end portion 31a of the motor case 31 is supported on the hub case H side via the first reduction ring gear 54 and the first reduction ring gear support bearing B7. It is not necessary to support the 31a side, and accordingly, there is a space around the hub shaft 11.
  • both side walls s1, s2 (first and second carrier halves 53a, 53b) of the speed reduction carrier 53 are connected to the speed reduction carrier supporting first and second bearings B6, B6. Since it is supported on the hub axle 11 via B6 ', the deceleration carrier 53 that is wide in the axial direction can be supported at both ends with a long support span in the axial direction. Thereby, the stable support of the deceleration carrier 53 is achieved, aiming at size reduction of the power unit U.
  • the first reduction ring gear 54 of the present embodiment integrally has a ring gear extension 54a that extends in the axial direction from the one end 31a of the motor case 31 to the outside of the motor case 31, and this ring gear extension 54a. Since the peripheral surface is the mounting surface of the first reduction ring gear support bearing B7, a sufficient bearing diameter can be secured without specially increasing the diameter of the motor case 31 itself.
  • the first reduction ring gear support bearing B7 includes the outer periphery of the ring gear extension 54a 'of the first reduction ring gear 54 and the inner periphery of the outer extension 61' of the second end wall member half body He2.
  • the first embodiment only the outer peripheral surface of the ring gear extension 54a 'and the inner peripheral surface of the outer extension 61' serve as the mounting surface of the first reduction ring gear support bearing B7. It differs from the form.
  • each component in FIG. 6 corresponds to the corresponding component of the first embodiment. Only the same reference numerals are attached, and further description of the structure is omitted. Thus, also in the second embodiment, the same effect as the first embodiment can be expected.
  • an annular gap is defined between the opposed peripheral surfaces of the outer extending portions 61 and 61 ′ and the inner extending portions 62 and 62 ′ that protrude from the inner side surface in the axial direction of the end wall member He.
  • the ring gear extension portions 54a and 54a 'of the first reduction ring gear 54 are inserted into the annular gap, and the circumferential surfaces of the ring gear extension portions 54a and 54a' facing the annular gap are provided with the first reduction ring gear support bearing B7.
  • the mounting surface is provided.
  • an inner extending portion 62 ′′ is integrally connected to the inner peripheral side of the outer extending portion 61 ′′ projecting on the inner side surface in the axial direction of the end wall member He to extend the inner side.
  • the rigidity of the portion 62 ′′ (and hence the second reduction ring gear 55) is increased, and the extension end of the ring gear extension 54a ′′ of the first reduction ring gear 54 is opposed to the extension end of the inner extension 62 ′′. is doing.
  • the power unit U is disposed on the rear wheel, but this can also be disposed on the front wheel.
  • the vehicle on which the power unit U is mounted is described as a battery-assisted bicycle.
  • the power unit of the present invention can also be applied to a stepping-type battery-assisted three-wheeled vehicle.
  • the vehicle equipped with the power unit U is an electrically assisted vehicle (that is, an electrically assisted bicycle, an electrically assisted tricycle, and a four wheel vehicle) that uses both electric power and human power (stepping input) for driving wheels.
  • an electric vehicle of a type in which wheels are exclusively driven electrically for example, an electric motorcycle, an electric three-wheeled vehicle, and the like.
  • the second reduction ring gear 55 is moved from the second reduction ring gear 55 to the hub case H side between the hub case H (end wall member He) and the second reduction ring gear 55.
  • a one-way clutch that transmits power only may be arranged.

Abstract

A power unit for an electric vehicle, wherein a reduction mechanism (R) comprises a reduction sun gear (51) rotatably driven by a motor (M), a reduction carrier (53) that rotatably supports a first gear (52a) meshing with the reduction sun gear and a second gear (52b) coaxially aligned with the first gear, a first reduction ring gear (54) that is fitted in an open end part (31a) of a motor case (31) and that meshes with the first gear, and a second reduction ring gear (55) that is provided to one end wall part (He) of a hub case (H) and that meshes with the second gear, a bearing (B7) for rotatably supporting the first reduction ring gear (54) on the hub case (H) being interposed between the first reduction ring gear (54) and the hub case (H). It is thereby possible to stably and firmly support the motor-case-side first reduction ring gear on the hub case while ensuring a high reduction ratio in the reduction mechanism for transmitting driving force of the motor to the hub case.

Description

電動車両用動力ユニットPower unit for electric vehicles
　本発明は、車両、特にハブ軸に回転可能に支持される車輪のハブケースに、モータと、モータの駆動力を減速してハブケースに伝達する減速機構部とが軸方向に並んで収容される電動車両用動力ユニットに関する。 The present invention relates to an electric motor in which a motor and a speed reduction mechanism that decelerates the driving force of the motor and transmits it to the hub case are accommodated side by side in an axial direction in a vehicle, particularly a wheel hub case rotatably supported by a hub shaft. The present invention relates to a vehicle power unit.
　尚、本発明及び本明細書において、「軸方向」及び「径方向」は、それぞれハブ軸を基準にした軸方向及び径方向をいう。 In the present invention and this specification, “axial direction” and “radial direction” refer to an axial direction and a radial direction based on the hub axis, respectively.
　上記電動車両用動力ユニットとして、遊星歯車機構よりなる減速機構部を、モータにより回転駆動される減速サンギヤと、減速サンギヤに噛合する減速遊星ギヤを回転自在に支持する減速キャリアと、有底筒状をなすモータケース（第１ケース部材３２）の開放端部に固定されて減速遊星ギヤに噛合する減速リングギヤとを備え、モータケースの閉塞端部がハブ軸に固定、支持されるものが知られている（例えば、下記特許文献１を参照）。 As the power unit for the electric vehicle, a speed reduction mechanism portion including a planetary gear mechanism is provided. A speed reduction sun gear that is rotationally driven by a motor, a speed reduction carrier that rotatably supports a speed reduction planetary gear meshing with the speed reduction sun gear, and a bottomed cylindrical shape And a reduction ring gear that is fixed to the open end of the motor case (first case member 32) and meshes with the reduction planetary gear, and the closed end of the motor case is fixed to and supported by the hub axle. (For example, refer to Patent Document 1 below).
日本特許第５３００８３０号公報Japanese Patent No. 5300830
　ところで上記従来構造では、モータケースの、ハブ軸への支持点（即ち閉塞端部）より軸方向に離間した自由端部（即ち開放端部）に減速リングギヤが固定されていて、ハブ軸に対しては減速リングギヤが片持ち状に支持される支持形態となる。そのため、モータの回転振動等に因り減速リングギヤが振動し易くなり、その振動で減速リングギヤと減速遊星ギヤとの噛合部の歯当たり不良や偏摩耗、噛合による騒音発生等の問題が生じる虞れがあった。 By the way, in the above conventional structure, the reduction ring gear is fixed to the free end portion (that is, the open end portion) of the motor case that is separated in the axial direction from the support point (that is, the closed end portion) to the hub shaft. Thus, the reduction ring gear is supported in a cantilever manner. Therefore, the reduction ring gear is likely to vibrate due to the rotational vibration of the motor, and the vibration may cause problems such as poor contact of the meshing portion between the reduction ring gear and the reduction planetary gear, uneven wear, and noise generation due to meshing. there were.
　本発明は、かかる事情に鑑みてなされたもので、減速機構部において高い減速比を確保しつつ、減速リングギヤをハブケースに安定よく強固に支持できるようにして上記問題を解決可能とした電動車両用動力ユニットを提供することを目的とする。 The present invention has been made in view of such circumstances, and for an electric vehicle capable of solving the above-mentioned problem by ensuring that the reduction ring gear can be stably and firmly supported on the hub case while ensuring a high reduction ratio in the reduction mechanism. An object is to provide a power unit.
　上記目的を達成するために、本発明は、車輪のハブケースの一端壁部及び他端壁部がハブ軸に各々回転可能に支持されると共に、該ハブケースに、モータと、前記モータの駆動力を減速して該ハブケースに伝達する減速機構部とが軸方向に並んで収容され、前記モータは、一端部が開放し且つ前記ハブケースの前記一端壁部に対向する有底筒状のモータケースを有すると共に、該モータケースの底壁となる他端部が前記ハブ軸に固定、支持される電動車両用動力ユニットであって、前記減速機構部は、前記モータにより回転駆動される減速サンギヤと、前記減速サンギヤに噛合する第１ギヤ、及び該第１ギヤに対し同軸に並ぶ第２ギヤを回転自在に支持する減速キャリアと、前記モータケースの前記一端部に嵌着されて前記第１ギヤに噛合する第１減速リングギヤと、前記ハブケースに設けられて前記第２ギヤに噛合する第２減速リングギヤとを備え、前記第１減速リングギヤと前記ハブケースとの間には、該第１減速リングギヤを該ハブケースに回転自在に支持させる軸受が介装されることを第１の特徴とする。 In order to achieve the above object, according to the present invention, one end wall portion and the other end wall portion of a hub case of a wheel are rotatably supported by a hub shaft, and a motor and a driving force of the motor are provided to the hub case. A speed reduction mechanism that decelerates and transmits to the hub case is housed side by side in the axial direction, and the motor has a bottomed cylindrical motor case that is open at one end and faces the one end wall of the hub case. In addition, the other end portion which becomes the bottom wall of the motor case is a power unit for an electric vehicle fixed and supported on the hub shaft, and the speed reduction mechanism portion includes a speed reduction sun gear which is rotationally driven by the motor, A first gear that meshes with the reduction sun gear, a speed reduction carrier that rotatably supports a second gear arranged coaxially with the first gear, and meshed with the first gear by being fitted to the one end portion of the motor case A first reduction ring gear, and a second reduction ring gear provided on the hub case and meshing with the second gear, and the first reduction ring gear is disposed between the first reduction ring gear and the hub case. A first feature is that a bearing that is rotatably supported by the actuator is interposed.
　また本発明は、第１の特徴に加えて、前記減速キャリアの、前記第１，第２ギヤを軸方向に挟む両側壁部がそれぞれ前記ハブ軸に回転自在に支持されることを第２の特徴とする。 According to the second aspect of the invention, in addition to the first feature, the two side walls of the speed reduction carrier that sandwich the first and second gears in the axial direction are rotatably supported by the hub shaft. Features.
　また本発明は、第１又は第２の特徴に加えて、前記第１減速リングギヤは、前記モータケースの前記一端部より該モータケース外に軸方向に延出するリングギヤ延出部を一体に有していて、該延出部の外周面又は内周面が前記軸受の、前記第１減速リングギヤ側の取付面とされることを第３の特徴とする。 Further, according to the present invention, in addition to the first or second feature, the first reduction ring gear integrally has a ring gear extending portion extending in the axial direction from the one end portion of the motor case to the outside of the motor case. The third feature is that the outer peripheral surface or inner peripheral surface of the extending portion is the mounting surface of the bearing on the first reduction ring gear side.
　本発明の第１の特徴によれば、遊星歯車機構よりなる減速機構部の遊星ギヤが同軸の第１，第２ギヤを有し、第１ギヤに噛合する第１減速リングギヤを有底筒状のモータケースの一端部（開放端部）に嵌着し、第２ギヤに噛合する第２減速リングギヤをハブケースに設け、第１減速リングギヤとハブケースとの間に、第１減速リングギヤをハブケースに回転自在に支持させる軸受を介装したので、減速機構部において、高い減速比を確保しつつ、第１，第２減速リングギヤの支持剛性を高めることができる。 According to the first feature of the present invention, the planetary gear of the speed reduction mechanism portion formed by the planetary gear mechanism has the coaxial first and second gears, and the first reduction ring gear meshing with the first gear has a bottomed cylindrical shape. A second reduction ring gear that fits to one end (open end) of the motor case and meshes with the second gear is provided in the hub case, and the first reduction ring gear rotates to the hub case between the first reduction ring gear and the hub case. Since the bearing to be freely supported is interposed, the support rigidity of the first and second reduction ring gears can be increased while ensuring a high reduction ratio in the reduction mechanism.
　特に第１減速リングギヤは、これがモータケースの自由端部（一端部）に固定されていて、ハブ軸に対しては片持ち支持形態であるが、この第１減速リングギヤを、軸受を介してハブケースに回転自在に支持させたことで、第１減速リングギヤが実質的に両持ち支持形態となって支持が安定し、軸ずれ防止に有効である。これにより、第１減速リングギヤにモータの回転振動が直接伝達されても、第１減速リングギヤの振動を効果的に抑制できるため、第１減速リングギヤと減速遊星ギヤとの噛合部の歯当たりを良好にして耐久性を高めることができ、また噛合部からの騒音の発生を低減可能となる。 In particular, the first reduction ring gear is fixed to the free end (one end) of the motor case and is in a cantilevered form with respect to the hub shaft. The first reduction ring gear is connected to the hub case via a bearing. Since the first reduction ring gear is substantially supported by both ends, the support is stable and effective in preventing shaft misalignment. As a result, even if the rotational vibration of the motor is directly transmitted to the first reduction ring gear, the vibration of the first reduction ring gear can be effectively suppressed. Therefore, the contact of the meshing portion between the first reduction ring gear and the reduction planetary gear is good. Thus, the durability can be enhanced and the generation of noise from the meshing portion can be reduced.
　また特に第２の特徴によれば、減速キャリアの、第１，第２ギヤを軸方向に挟む両側壁部がそれぞれハブ軸上に回転自在に支持されるので、モータケースの開放端部（一端部）を第１減速リングギヤ及び軸受を介してハブケース側に支持させたことに伴いハブ軸の周囲に生じたスペースを利用して、減速キャリアを軸方向に長い支持スパンを以て両持ち支持可能となる。これにより、動力ユニットの小型化を図りつつ減速キャリアを安定よく支持することができる。 In particular, according to the second feature, both side wall portions of the speed reduction carrier sandwiching the first and second gears in the axial direction are rotatably supported on the hub shaft, so that the open end portion (one end of the motor case) Part) is supported on the hub case side through the first reduction ring gear and the bearing, and the reduction carrier can be supported at both ends with a long support span in the axial direction by utilizing the space generated around the hub shaft. . As a result, the speed reduction carrier can be stably supported while reducing the size of the power unit.
　また特に第３の特徴によれば、第１減速リングギヤは、モータケースの一端部よりモータケース外に軸方向に延出するリングギヤ延出部を一体に有していて、このリングギヤ延出部の外周面又は内周面が軸受の、第１減速リングギヤ側の取付面とされるので、モータケース径を特別に大径化しなくても軸受径を容易に確保可能となり、動力ユニットの更なる小型化に寄与することができる。 In particular, according to the third feature, the first reduction ring gear integrally has a ring gear extending portion extending axially out of the motor case from one end portion of the motor case. Since the outer peripheral surface or inner peripheral surface is the mounting surface on the first reduction ring gear side of the bearing, it is possible to easily secure the bearing diameter without specially increasing the motor case diameter, and further reducing the size of the power unit It can contribute to the conversion.
図１は本発明の第１実施形態における電動補助自転車用動力ユニットの全体縦断面図である。（第１の実施の形態）FIG. 1 is an overall longitudinal sectional view of a power unit for a battery-assisted bicycle according to a first embodiment of the present invention. (First embodiment) 図２は図１の２矢視部拡大図である。（第１の実施の形態）FIG. 2 is an enlarged view taken along the arrow 2 in FIG. (First embodiment) 図３は図１の３矢視部拡大図（図４の３－３線断面図）である。（第１の実施の形態）3 is an enlarged view taken along the line 3 in FIG. 1 (a cross-sectional view taken along line 3-3 in FIG. 4). (First embodiment) 図４はハブ軸に対する変速サンギヤのロック状態を示すものであって、図４（Ａ）は、図３の４Ａ－４Ａ線断面図、図４（Ｂ）は図３の４Ｂ－４Ｂ線断面図である。（第１の実施の形態）4 shows the locked state of the transmission sun gear with respect to the hub shaft. FIG. 4 (A) is a sectional view taken along line 4A-4A in FIG. 3, and FIG. 4 (B) is a sectional view taken along line 4B-4B in FIG. It is. (First embodiment) 図５はハブ軸に対する変速サンギヤのアンロック状態を示すものであって、図５（Ａ）は、図４の（Ａ）対応図、図５（Ｂ）は、図４の（Ｂ）対応図である。（第１の実施の形態）5A and 5B show the unlocked state of the transmission sun gear with respect to the hub shaft. FIG. 5A is a diagram corresponding to FIG. 4A, and FIG. 5B is a diagram corresponding to FIG. It is. (First embodiment) 図６は本発明の第２実施形態を示す図２対応図である。（第２の実施の形態）FIG. 6 is a view corresponding to FIG. 2 showing a second embodiment of the present invention. (Second Embodiment) 図７は本発明の第３実施形態を示す図２・図６対応図である。（第３の実施の形態）FIG. 7 is a view corresponding to FIGS. 2 and 6 showing a third embodiment of the present invention. (Third embodiment)
Ｂ７・・・・第１減速リングギヤ支持用軸受（軸受）
Ｈ・・・・・ハブケース
Ｈｅ・・・・端壁部材（一端壁部）
Ｈｍｂ・・・端壁部（他端壁部）
Ｍ・・・・・モータ
Ｒ・・・・・減速機構部
ｓ１，ｓ２・・第１，第２側壁部（側壁部）
Ｕ・・・・・電動補助自転車用動力ユニット（電動車両用動力ユニット）
１１・・・・ハブ軸
３１ａ・・・一端部
３１・・・・モータケース
３１ｂ・・・端壁部（他端部）
５１・・・・減速サンギヤ
５２ａ，５２ｂ・・第１，第２ギヤ
５３・・・・減速キャリア
５４・・・・第１減速リングギヤ
５４ａ，５４ａ′，５４ａ″・・リングギヤ延出部
５５・・・・第２減速リングギヤ B7... First reduction ring gear support bearing (bearing)
H: Hub case He ... End wall member (one end wall)
Hmb ... end wall (other end wall)
M... Motor R... Deceleration mechanism part s1, s2 .. First and second side wall parts (side wall parts)
U: Power unit for battery-assisted bicycles (Power unit for electric vehicles)
11 .... hub shaft 31a ... one end 31 ... motor case 31b ... end wall (other end)
··· Deceleration sun gears 52a, 52b ··· First and second gears 53 ··· Reduction carrier 54 ··· First reduction ring gears 54a, 54a ', 54a "· · Ring gear extension 55 ·· ..Second reduction ring gear
　本発明の実施形態を、添付図面に基づいて以下に説明する。 Embodiments of the present invention will be described below with reference to the accompanying drawings.
第１の実施の形態First embodiment
　先ず、図１～図５に基づいて、本発明の電動車両用動力ユニットの第１実施形態を説明する。 First, a first embodiment of an electric vehicle power unit according to the present invention will be described with reference to FIGS.
　電動車両用動力ユニットの一例である電動補助自転車用動力ユニットＵは、電動自転車の車輪、例えば後輪の車軸として機能する単一のハブ軸１１と、後輪のハブ部として機能すべくハブ軸１１に回転可能に支持されるハブケースＨと、ハブケースＨに収容されて、ペダルから入力された踏力を変速可能にハブケースＨに伝達する変速機構部Ｔと、ハブケースＨ内で変速機構部Ｔに対し軸方向に隣接配置されてハブケースＨを電動で駆動し得るモータ駆動系ＭＤとを備える。 An electric assist bicycle power unit U, which is an example of an electric vehicle power unit, includes a single hub shaft 11 that functions as a wheel of an electric bicycle, for example, a rear wheel axle, and a hub shaft that functions as a hub portion of a rear wheel. 11, a hub case H that is rotatably supported by the motor 11, a transmission mechanism T that is housed in the hub case H and that transmits a pedaling force input from a pedal to the hub case H so as to be capable of shifting, and the transmission mechanism T in the hub case H And a motor drive system MD that is adjacently disposed in the axial direction and can drive the hub case H electrically.
　ハブ軸１１は、本実施形態では鍛造又は機械加工により一体物の軸として形成される。ハブ軸１１の両端部は、図示はしないが、従来周知の電動自転車と同様に、左右のリヤフォークに嵌挿、支持され、且つナット等の締結手段で結合、固定される。 In the present embodiment, the hub shaft 11 is formed as an integral shaft by forging or machining. Although not shown, both end portions of the hub shaft 11 are inserted and supported by the left and right rear forks, and are coupled and fixed by fastening means such as nuts, as in a conventionally known electric bicycle.
　ハブケースＨは、一端が開放され且つ他端に端壁部Ｈｍｂを一体に有する有底円筒状のハブケース本体Ｈｍと、ハブケース本体Ｈｍの開放された一端部Ｈｍｅに着脱可能に結合される環状の端壁部材Ｈｅとを備える。 The hub case H has a bottomed cylindrical hub case body Hm having one end opened and an end wall Hmb integrally formed at the other end, and an annular end detachably coupled to the opened one end Hme of the hub case body Hm. A wall member He.
　端壁部材Ｈｅは、本実施形態では製作加工を容易化するために、例えば円環状の第１端壁部材半体Ｈｅ１と、第１端壁部材半体Ｈｅ１を囲繞するようにして第１端壁部材半体Ｈｅ１の外周部に嵌合、固定される第２端壁部材半体Ｈｅ２とより分割構成される。第２端壁部材半体Ｈｅ２の外周部はハブケース本体Ｈｍの一端部Ｈｍｅにインロー嵌合される。第１，第２端壁部材半体Ｈｅ１，Ｈｅ２の相互間は、適当な結合手段、例えば圧入、溶接、螺合等により結合してもよく、或いは一体に形成してもよい。 In this embodiment, the end wall member He has a first end so as to surround the first end wall member half He1 and the first end wall member half He1, for example. The second end wall member half body He <b> 2 is fitted and fixed to the outer peripheral portion of the wall member half body He <b> 1. The outer peripheral portion of the second end wall member half body He2 is inlay-fitted to one end portion Hme of the hub case main body Hm. The first and second end wall member halves He1 and He2 may be coupled to each other by an appropriate coupling means, for example, press fitting, welding, screwing, or the like, or may be integrally formed.
　端壁部材Ｈｅのハブケース本体Ｈｍへの結合手段は、本実施形態では端壁部材Ｈｅ（より具体的には第２端壁部材半体Ｈｅ２）を貫通してハブケース本体Ｈｍの一端部Ｈｍｅの外周ボス部に螺挿される複数のボルト１４で構成されるが、その他の適当な結合手段、例えば圧入も採用可能である。ハブケース本体Ｈｍの外周部には、後輪のスポーク（図示せず）が固定される。 In this embodiment, the coupling means of the end wall member He to the hub case main body Hm penetrates the end wall member He (more specifically, the second end wall member half body He2), and the outer periphery of the one end Hme of the hub case main body Hm. Although constituted by a plurality of bolts 14 screwed into the boss portion, other suitable coupling means such as press-fitting can also be adopted. A rear wheel spoke (not shown) is fixed to the outer periphery of the hub case body Hm.
　ハブケースＨは、これの端壁部Ｈｍｂがハブ支持用第１軸受Ｂ１を介して、また端壁部材Ｈｅがハブ支持用第２軸受Ｂ２を介してそれぞれハブ軸１１に回転自在に支持される。　　　 The end wall Hmb of the hub case H is rotatably supported by the hub shaft 11 via the hub supporting first bearing B1 and the end wall member He via the hub supporting second bearing B2. *
　その支持構造をより具体的に説明すると、ハブ軸１１には、ハブ支持用第１軸受Ｂ１を端壁部Ｈｍｂ内周との間で保持するハブ支持リング１５ｒが、支持ナット１５ｎを介して支持される。支持ナット１５ｎは、ハブ支持リング１５ｒの内周部を嵌合、支持するものであって、ハブ軸１１に螺合され、その螺合位置はロックナット１６で固定される。而して、端壁部Ｈｍｂをハブ支持用第１軸受Ｂ１及びハブ支持リング１５ｒを介してハブ軸１１に支持させる組立工程では、支持ナット１５ｎによりハブ支持用第１軸受Ｂ１に対する予圧を調整可能である。 The support structure will be described more specifically. A hub support ring 15r that holds the hub support first bearing B1 between the inner periphery of the end wall portion Hmb and the hub shaft 11 is supported via a support nut 15n. Is done. The support nut 15n fits and supports the inner peripheral portion of the hub support ring 15r. The support nut 15n is screwed to the hub shaft 11, and the screwed position is fixed by the lock nut 16. Thus, in the assembly process in which the end wall Hmb is supported on the hub shaft 11 via the hub support first bearing B1 and the hub support ring 15r, the preload on the hub support first bearing B1 can be adjusted by the support nut 15n. It is.
　またハブ軸１１には、ハブ支持用第２軸受Ｂ２を端壁部材Ｈｅ（より具体的には第１端壁部材半体Ｈｅ１）内周との間で保持する、変速機構部Ｔの変速キャリア２２が、後述するようにキャリア支持用軸受Ｂ３を介して回転可能に支持される。 Further, the hub shaft 11 has a transmission carrier of the transmission mechanism T that holds the hub supporting second bearing B2 between the inner periphery of the end wall member He (more specifically, the first end wall member half body He1). 22 is rotatably supported via a carrier support bearing B3 as will be described later.
　尚、ハブ支持用第１，第２軸受Ｂ１，Ｂ２は、ハブ軸１１と直交する投影面で見て、モータ駆動系ＭＤ（従ってモータＭ）の外径よりも径方向内方側に配置される。 The hub supporting first and second bearings B1 and B2 are arranged on the radially inner side of the outer diameter of the motor drive system MD (and therefore the motor M) when viewed in a projection plane orthogonal to the hub shaft 11. The
　次に変速機構部Ｔの一例を説明する。変速機構部Ｔは、ペダルからの踏力が入力される入力部材としての被動スプロケット２１と、被動スプロケット２１に一体に回転するよう結合されてハブ軸１１上を回転可能な変速キャリア２２と、ハブ軸１１の外周に回転自在に嵌合、支持された変速サンギヤ２３と、変速サンギヤ２３及びハブ軸１１間に介装されて変速サンギヤ２３をハブ軸１１に固定状態と回転可能状態とに切換え可能な切換手段としてのシフト機構Ｓと、変速キャリア２２に回転可能に支持されて変速サンギヤ２３に噛合する複数の変速遊星ギヤ２４と、変速遊星ギヤ２４に噛合する変速リングギヤ２５と、変速サンギヤ２３のハブ軸１１に対する前記固定状態では変速キャリア２２に入力された踏力を変速遊星ギヤ２４及び変速リングギヤ２５を介してハブケースＨの端壁部材Ｈｅに伝達させ、また前記回転可能状態では上記踏力を変速遊星ギヤ２４を介さずに端壁部材Ｈｅに伝達させる一方向伝動機構ＯＴとを備える。 Next, an example of the transmission mechanism T will be described. The transmission mechanism T includes a driven sprocket 21 as an input member to which a pedaling force from a pedal is input, a transmission carrier 22 that is coupled to the driven sprocket 21 so as to rotate integrally with the driven sprocket 21, and can rotate on the hub shaft 11. The transmission sun gear 23 is rotatably fitted and supported on the outer periphery of the motor 11, and is interposed between the transmission sun gear 23 and the hub shaft 11 so that the transmission sun gear 23 can be switched between a fixed state and a rotatable state on the hub shaft 11. A shift mechanism S as switching means, a plurality of transmission planetary gears 24 rotatably supported on the transmission carrier 22 and meshing with the transmission sun gear 23, a transmission ring gear 25 meshing with the transmission planetary gear 24, and a hub of the transmission sun gear 23 In the fixed state with respect to the shaft 11, the pedal force input to the speed change carrier 22 is transferred to the hub case via the speed change planetary gear 24 and the speed change ring gear 25. Is transmitted to the end wall member He, also in the rotatable state and a one-way transmission mechanism OT for transmitting to the end wall member He without via the transmission planetary gear 24 to the pedal force.
　被動スプロケット２１には、被動スプロケット２１を含むチェーン伝動機構を介してペダルの踏力が回転力として伝達され、その回転力が変速キャリア２２に伝わり、更に変速機構部Ｔを介してハブケースＨに伝達されて後輪を駆動する。 The pedal treading force is transmitted as a rotational force to the driven sprocket 21 through a chain transmission mechanism including the driven sprocket 21, and the rotational force is transmitted to the transmission carrier 22 and further transmitted to the hub case H through the transmission mechanism T. To drive the rear wheels.
　変速キャリア２２は、本実施形態では製作加工を容易化するために、例えば円筒状の第１キャリア半体２２Ａと、円板状の第２キャリア半体２２Ｂとより分割構成される。第１キャリア半体２２Ａの一端部２２Ａａは、キャリア軸２７の両端部を支持するキャリア軸支持壁部を一体に有しており、これにより、一端部２２Ａａは、キャリア軸２７、変速遊星ギヤ２４及び変速サンギヤ２３を介してハブ軸１１に支持される。一方、第１キャリア半体２２Ａの他端部２２Ａｂの内周と、ハブ軸１１外周に相対回転不能に嵌着（例えば圧入）されるストッパリング１７の外周との間にはキャリア支持用軸受Ｂ３が介装されており、これより、他端部２２Ａｂは、キャリア支持用軸受Ｂ３を介してハブ軸１１に回転自在に支持される。 In this embodiment, the transmission carrier 22 is divided into, for example, a cylindrical first carrier half body 22A and a disk-shaped second carrier half body 22B in order to facilitate manufacturing. One end 22Aa of the first carrier half 22A integrally has a carrier shaft support wall that supports both ends of the carrier shaft 27, whereby the one end 22Aa is connected to the carrier shaft 27 and the variable planetary gear 24. And supported by the hub shaft 11 via the transmission sun gear 23. On the other hand, between the inner periphery of the other end 22Ab of the first carrier half body 22A and the outer periphery of the stopper ring 17 that is non-rotatably fitted (for example, press-fitted) to the outer periphery of the hub shaft 11, the carrier support bearing B3. Thus, the other end 22Ab is rotatably supported by the hub shaft 11 via the carrier supporting bearing B3.
　また第１キャリア半体２２Ａの軸方向中間部の外周には、第２キャリア半体２２Ｂの内周部が圧入により嵌合、固定される。更に第１キャリア半体２２Ａの外周には、第２キャリア半体２２Ｂに隣接する被動スプロケット２１の各内周部がスプライン嵌合され、且つワッシャ２８及び止め輪２９により固定される。 Further, the inner peripheral portion of the second carrier half body 22B is fitted and fixed to the outer periphery of the intermediate portion in the axial direction of the first carrier half body 22A by press-fitting. Furthermore, each inner peripheral portion of the driven sprocket 21 adjacent to the second carrier half 22B is spline fitted to the outer periphery of the first carrier half 22A, and is fixed by a washer 28 and a retaining ring 29.
　尚、被動スプロケット２１の固定手段として、止め輪２９に代えて、他の適当な固定手段、例えばナットを使用してもよい。尚また、第１，第２キャリア半体２２Ａ，２２Ｂの相互は、他の適当な結合手段、例えば溶接、螺合、接着等により結合してもよく、或いは一体に形成してもよい。 In addition, instead of the retaining ring 29, other suitable fixing means, for example, a nut, may be used as the fixing means for the driven sprocket 21. In addition, the first and second carrier halves 22A and 22B may be coupled to each other by other suitable coupling means such as welding, screwing, bonding, or the like, or may be integrally formed.
　また第２キャリア半体２２Ｂの外周部の軸方向内側面には、モータＭ側に延びる円筒状のキャリア延出部２２Ｂａが一体に突設され、キャリア延出部２２Ｂａは、変速リングギヤ２５よりも大径の円筒状に形成される。そして、キャリア延出部２２Ｂａの外周と、端壁部材Ｈｅ（より具体的には第２端壁部材半体Ｈｅ２）の内周との対向周面間には、前述のハブ支持用第２軸受Ｂ２が介装される。 A cylindrical carrier extension 22Ba extending toward the motor M is integrally formed on the axial inner side surface of the outer peripheral portion of the second carrier half 22B, and the carrier extension 22Ba is more than the transmission ring gear 25. It is formed in a large diameter cylindrical shape. Between the outer peripheral surface of the carrier extension portion 22Ba and the opposed peripheral surface between the inner periphery of the end wall member He (more specifically, the second end wall member half body He2), the above-described second bearing for hub support is provided. B2 is interposed.
　変速リングギヤ２５は、変速遊星ギヤ２４と噛合する内歯２５ｍｇを有するリングギヤ本体部２５ｍと、リングギヤ本体部２５ｍから軸方向でモータ駆動系ＭＤとは反対側に延びるリングギヤ延出部２５ａとを一体に有しており、リングギヤ延出部２５ａは、キャリア延出部２２Ｂａにより同心状に囲繞される。リングギヤ延出部２５ａの内周と変速キャリア２２（より具体的には第１キャリア半体２２Ａの一端部２２Ａａ）外周との対向周面間には、変速リングギヤ支持用軸受Ｂ４が介装される。 The transmission ring gear 25 is integrally formed with a ring gear main body portion 25m having an inner tooth 25mg that meshes with the transmission planetary gear 24, and a ring gear extending portion 25a extending from the ring gear main body portion 25m in the opposite direction to the motor drive system MD in the axial direction. The ring gear extension 25a is concentrically surrounded by the carrier extension 22Ba. Between the inner circumference of the ring gear extension 25a and the outer circumference of the transmission carrier 22 (more specifically, the one end 22Aa of the first carrier half 22A), a transmission ring gear support bearing B4 is interposed. .
　次に一方向伝動機構ＯＴの一例を説明する。一方向伝動機構ＯＴは、変速リングギヤ２５及び端壁部材Ｈｅ間に設けられて、変速リングギヤ２５から端壁部材Ｈｅ側へのみ動力伝達を可能とする第１ワンウェイクラッチＣ１と、第１ワンウェイクラッチＣ１とは軸方向にずれた位置で変速キャリア２２及び変速リングギヤ２５間に設けられて、変速キャリア２２から変速リングギヤ２５側へのみ動力伝達を可能とする第２ワンウェイクラッチＣ２とを備える。 Next, an example of the one-way transmission mechanism OT will be described. The one-way transmission mechanism OT is provided between the transmission ring gear 25 and the end wall member He, and can transmit power from the transmission ring gear 25 only to the end wall member He side, and the first one-way clutch C1. Is provided between the speed change carrier 22 and the speed change ring gear 25 at a position shifted in the axial direction, and includes a second one-way clutch C2 capable of transmitting power only from the speed change carrier 22 to the speed change ring gear 25.
　特に本実施形態において、第１ワンウェイクラッチＣ１は、リングギヤ本体部２５ｍの外周と第１端壁部材半体Ｈｅ１の内周ボス部６３との対向周面間に介装され、また第２ワンウェイクラッチＣ２は、キャリア延出部２２Ｂａの内周とリングギヤ延出部２５ａの外周との対向周面間に介装される。 In particular, in the present embodiment, the first one-way clutch C1 is interposed between the opposed peripheral surfaces of the outer periphery of the ring gear main body portion 25m and the inner peripheral boss portion 63 of the first end wall member half body He1, and the second one-way clutch. C2 is interposed between opposing peripheral surfaces of the inner periphery of the carrier extension portion 22Ba and the outer periphery of the ring gear extension portion 25a.
　而して、第２ワンウェイクラッチＣ２の少なくとも一部（本実施形態では大部分）と、変速リングギヤ支持用軸受Ｂ４の少なくとも一部（本実施形態では全部）とは軸方向で同一位置にあり、即ち径方向にオーバラップした配置である。また第２ワンウェイクラッチＣ２の少なくとも一部（本実施形態では全部）と、ハブ支持用第２軸受Ｂ２の少なくとも一部（本実施形態では大部分）とは軸方向で同一位置にあり、即ち径方向にオーバラップした配置である。 Thus, at least a part (most part in the present embodiment) of the second one-way clutch C2 and at least a part (all in the present embodiment) of the transmission ring gear support bearing B4 are in the same position in the axial direction. That is, the arrangement is overlapped in the radial direction. Further, at least a part (all in this embodiment) of the second one-way clutch C2 and at least a part (most part in the present embodiment) of the second hub supporting bearing B2 are in the same position in the axial direction, that is, the diameter. It is an arrangement that overlaps in the direction.
　第１，第２ワンウェイクラッチＣ１，Ｃ２は、従来周知のワンウェイクラッチ構造と同様の構造を有するものであって、図示はしないが、例えば、インナレース及びアウタレース相互の対向周面のうちの何れか一方の周面に間隔をおいて設けられる複数の係合溝と、その何れか他方の周面に揺動可能に軸支されて係合溝に係脱可能な係合子（例えばラチェット爪）と、各係合子を係合溝との係止方向に弾発するばねとを備える。尚、インナレース及びアウタレースは、第１，第２ワンウェイクラッチＣ１，Ｃ２が設けられる部材と別体、後付けでもよいし、或いは一体に形成してもよい。 The first and second one-way clutches C1 and C2 have the same structure as a conventionally well-known one-way clutch structure, and although not shown, for example, any one of the opposing circumferential surfaces of the inner race and the outer race A plurality of engagement grooves provided at intervals on one peripheral surface, and an engaging member (for example, a ratchet claw) that is pivotally supported on one of the other peripheral surfaces so as to be able to engage with and disengage from the engagement groove. And a spring that repels each engaging element in a locking direction with the engaging groove. The inner race and the outer race may be separated from the members provided with the first and second one-way clutches C1 and C2, may be retrofitted, or may be formed integrally.
　また、本実施形態では、変速リングギヤ２５における第１，第２ワンウェイクラッチＣ１，Ｃ２の取付面となるリングギヤ本体部２５ｍ及びリングギヤ延出部２５ａの各外周面が同一径である。また端壁部材Ｈｅにおける第１ワンウェイクラッチＣ１の取付面となる第１端壁部材半体Ｈｅ１の内周ボス部６３の内周面と、変速キャリア２２における第２ワンウェイクラッチＣ２の取付面となるキャリア延出部２２Ｂａの内周面も同一径である。従って、第１，第２ワンウェイクラッチＣ１，Ｃ２は、同一仕様の部品を使用可能となり、部品共通化によるコスト節減が図られる。但し、第１，第２ワンウェイクラッチＣ１，Ｃ２は、動力伝達方向が互いに逆向きであるため、第１ワンウェイクラッチＣ１における係合子及び係合溝の周方向の向きは、第２ワンウェイクラッチＣ２のそれとは互いに逆向きに設定される。 In this embodiment, the outer peripheral surfaces of the ring gear main body portion 25m and the ring gear extending portion 25a, which are the attachment surfaces of the first and second one-way clutches C1 and C2 in the transmission ring gear 25, have the same diameter. In addition, the inner peripheral surface of the inner peripheral boss 63 of the first end wall member half body He1 serving as the mounting surface of the first one-way clutch C1 in the end wall member He and the mounting surface of the second one-way clutch C2 in the transmission carrier 22 are provided. The inner peripheral surface of the carrier extension 22Ba has the same diameter. Accordingly, the first and second one-way clutches C1 and C2 can use parts having the same specifications, and cost savings can be achieved by sharing parts. However, since the power transmission directions of the first and second one-way clutches C1 and C2 are opposite to each other, the circumferential direction of the engagement element and the engagement groove in the first one-way clutch C1 is the same as that of the second one-way clutch C2. They are set in opposite directions.
　次にシフト機構Ｓの一例を、主として図３～図５を参照して説明する。 Next, an example of the shift mechanism S will be described mainly with reference to FIGS.
　シフト機構Ｓは、変速サンギヤ２３の内周面に周方向に間隔をおいて凹設された複数のラチェット溝２３ａと、ハブ軸１１の外周面に周方向に間隔をおいて凹設された複数の爪収納孔１１ａと、爪収納孔１１ａに起伏揺動可能に嵌合、支持され且つその起伏揺動により爪本体部４１ａの爪先部分４１ａｓがラチェット溝２３ａに係脱し得るラチェット爪４１と、ラチェット爪４１をラチェット溝２３ａへの係合方向（即ちラチェット爪４１の起立方向）に常時付勢すべくハブ軸１１外周に弾性収縮状態で嵌装され且つラチェット爪４１の中間部４１ｍ外周に圧接するリングばね４２と、ラチェット爪４１の基端部４１ｂの爪先部分４１ｂｓが出没可能な凹部４３１ｉを内周面に有すると共に所定のロック位置・アンロック位置間を回動可能としてハブ軸１１外周に嵌合支持される操作ドラム４３と、操作ドラム４３をアンロック位置（即ち図５（Ｂ）の位置）側に回動付勢すべく操作ドラム４３に可動端４４ａを係止させる捩じりばねよりなる戻しばね４４と、ハブ軸１１外周に相対回転不能に嵌着（例えば圧入）されて戻しばね４４の固定端４４ｂを係止させるばね受けリング４５と、操作ドラム４３の外端に隣接配置されてハブ軸１１外周に相対回転不能に嵌着（例えば圧入）される操作ドラム抜止め用の固定リング４６とを備えている。 The shift mechanism S includes a plurality of ratchet grooves 23 a that are recessed in the circumferential direction on the inner circumferential surface of the transmission sun gear 23, and a plurality that are recessed in the circumferential direction on the outer circumferential surface of the hub shaft 11. A claw storage hole 11a, a ratchet claw 41 which is fitted and supported so as to be able to swing up and down in the claw storage hole 11a, and by which the claw tip portion 41as of the claw body 41a can be engaged and disengaged with the ratchet groove 23a, and a ratchet The claw 41 is fitted in the outer periphery of the hub shaft 11 in an elastically contracted state and pressed against the outer periphery of the intermediate portion 41m of the ratchet claw 41 so as to constantly urge the claw 41 in the engagement direction with the ratchet groove 23a (that is, the standing direction of the ratchet claw 41). The ring spring 42 and a recess 431i in which the tip portion 41bs of the base end portion 41b of the ratchet pawl 41 can protrude and retract are provided on the inner peripheral surface and can be rotated between a predetermined lock position and an unlock position. Then, the operation drum 43 fitted and supported on the outer periphery of the hub shaft 11 and the movable end 44a is provided on the operation drum 43 so as to urge the operation drum 43 to the unlock position (namely, the position of FIG. 5B). A return spring 44 made of a torsion spring to be locked, a spring receiving ring 45 fitted to the outer periphery of the hub shaft 11 so as not to be relatively rotatable (for example, press-fitted) to lock the fixed end 44b of the return spring 44, and an operation drum 43 and a fixing ring 46 for retaining the operation drum, which is disposed adjacent to the outer end of 43 and fitted into the outer periphery of the hub shaft 11 so as not to be relatively rotatable (for example, press-fitted).
　操作ドラム４３は、相対回転不能に相互が連結（例えば噛み合い結合）される第１，第２ドラム半体４３１，４３２より分割構成される。第２ドラム半体４３２の外端からは、操作ドラム４３の周方向に間隔をおいて並ぶ複数の操作杆部４３２ｔが軸方向外方側に一体に延出している。そして、各操作杆部４３２ｔは、固定リング４６及びストッパリング１７の各内周面にそれぞれ凹設した挿通溝を緩く貫通して変速キャリア２２の外方に突出する。操作杆部４３２ｔは、後述する操作ユニットＣＵにより操作ドラム４３をロック位置・アンロック位置間で回動操作できるようになっている。 The operation drum 43 is divided into first and second drum halves 431 and 432 that are connected to each other so as not to rotate relative to each other (for example, meshing and coupling). From the outer end of the second drum half 432, a plurality of operating rod portions 432t arranged at intervals in the circumferential direction of the operating drum 43 are integrally extended outward in the axial direction. Each operation lever 432t protrudes outwardly from the speed change carrier 22 through the insertion grooves formed in the inner peripheral surfaces of the fixing ring 46 and the stopper ring 17 respectively. The operation lever 432t can rotate the operation drum 43 between a lock position and an unlock position by an operation unit CU described later.
　而して、操作ドラム４３が、図５（Ｂ）に示すアンロック位置に保持されるときは、操作ドラム４３に連動するラチェット爪４１の爪本体部４１ａがリングばね４２の付勢力に抗してラチェット溝２３ａから離脱した状態（即ち爪収納孔１１ａへの収納状態）におかれる。これにより、変速サンギヤ２３がハブ軸１１に対し回転可能状態となり、変速遊星ギヤ２４も変速サンギヤ２３と同様、フリー回転可能である。そのため、踏力に応動した変速キャリア２２の回転は、第２ワンウェイクラッチＣ２、変速リングギヤ２５、第１ワンウェイクラッチＣ１を経て端壁部材Ｈｅ従ってハブケースＨに直接（即ち変速遊星ギヤ２４を介さずに）伝達される。かくして、変速機構部Ｔにおいて第１速が確立する。 Thus, when the operation drum 43 is held at the unlock position shown in FIG. 5B, the claw body 41a of the ratchet claw 41 interlocked with the operation drum 43 resists the urging force of the ring spring 42. Thus, it is placed in a state of being detached from the ratchet groove 23a (ie, stored in the claw storage hole 11a). As a result, the transmission sun gear 23 becomes rotatable with respect to the hub shaft 11, and the transmission planetary gear 24 is free to rotate as well as the transmission sun gear 23. Therefore, the rotation of the speed change carrier 22 in response to the pedaling force is directly transmitted to the end wall member He and thus to the hub case H via the second one-way clutch C2, the speed change ring gear 25, and the first one-way clutch C1 (that is, not via the speed change planetary gear 24). Communicated. Thus, the first speed is established in the transmission mechanism T.
　それに対し、操作ドラム４３が戻しばね４４に抗して図４（Ｂ）に示すロック位置に保持されるときは、操作ドラム４３より解放されたラチェット爪４１が、リングばね４２の付勢力に基づきラチェット溝２３ａへの係止状態に切換わるため、変速サンギヤ２３がハブ軸１１に対し接続即ち固定状態となって回転不能となる。これにより、変速サンギヤ２３と噛合する変速遊星ギヤ２４が、変速キャリア２２の回転に伴いハブ軸１１回りを公転しつつ変速キャリア軸２７回りを自転するため、変速キャリア２２の回転は、変速遊星ギヤ２４で増速されて変速リングギヤ２５に伝達され、その増速された変速リングギヤ２５の回転が第２ワンウェイクラッチＣ２を経て端壁部材Ｈｅ従ってハブケースＨに伝達される。かくして、変速機構部Ｔにおいて第１速よりも増速された第２速が確立する。 On the other hand, when the operation drum 43 is held at the lock position shown in FIG. 4B against the return spring 44, the ratchet pawl 41 released from the operation drum 43 is based on the biasing force of the ring spring 42. Since the state is switched to the latched state in the ratchet groove 23a, the transmission sun gear 23 is connected to the hub shaft 11, that is, in a fixed state and cannot be rotated. As a result, the speed change planetary gear 24 meshed with the speed change sun gear 23 revolves around the speed change carrier shaft 27 while revolving around the hub shaft 11 as the speed change carrier 22 rotates, so that the speed change planet 22 rotates. The speed is increased at 24 and transmitted to the transmission ring gear 25, and the increased rotation of the transmission ring gear 25 is transmitted to the end wall member He and thus to the hub case H via the second one-way clutch C <b> 2. Thus, the second speed increased from the first speed in the transmission mechanism T is established.
　ところでハブ軸１１の外周には、シフト機構Ｓを切換操作するための操作ユニットＣＵのユニットケースＣＵｃが、変速キャリア２２の軸方向外方側に隣接した位置でナット１８により固定される。ユニットケースＣＵｃ内には、シフト機構Ｓの操作杆部４３２ｔに係合して操作ドラム４３を回動操作し得る作動板７１が回動可能に収容、支持される。 Incidentally, a unit case CUc of an operation unit CU for switching the shift mechanism S is fixed to the outer periphery of the hub shaft 11 by a nut 18 at a position adjacent to the outer side in the axial direction of the transmission carrier 22. In the unit case CUc, an operation plate 71 that can engage with the operation lever portion 432t of the shift mechanism S and can rotate the operation drum 43 is accommodated and supported in a rotatable manner.
　作動板７１には、ユニットケースＣＵｃ外に張り出して作動板７１を回動操作可能な操作レバー７２が連結され、操作レバー７２は、外部から遠隔操作可能である。従って、乗員は、手元操作で操作ユニットＣＵを操作でき、その操作入力に基づいてシフト機構Ｓの操作ドラム４３をロック位置・アンロック位置の何れかに選択的に切換えることにより、前述の第１速と第２速の変速切換操作を任意に行うことができる。 The operation plate 71 is connected to an operation lever 72 that protrudes outside the unit case CUc and can rotate the operation plate 71. The operation lever 72 can be remotely operated from the outside. Therefore, the occupant can operate the operation unit CU by hand operation, and by selectively switching the operation drum 43 of the shift mechanism S to either the lock position or the unlock position based on the operation input, the first operation described above is performed. The speed change operation between the second speed and the second speed can be arbitrarily performed.
　次にモータ駆動系ＭＤの一例を説明する。モータ駆動系ＭＤは、電動式のモータＭと、モータＭの駆動力を減速してハブケースＨの端壁部材Ｈｅに伝達する減速機構部Ｒとを備える。 Next, an example of the motor drive system MD will be described. The motor drive system MD includes an electric motor M and a speed reduction mechanism R that decelerates the driving force of the motor M and transmits it to the end wall member He of the hub case H.
　モータＭは、例えば、一端部３１ａが開放され且つ端壁部材Ｈｅに対向する有底円筒状のモータケース３１と、モータケース３１の胴部内周面に固着したステータ３２と、ステータ３２の径方向内方側に配置される永久磁石付きロータ３３と、ロータ３３を外周部に固定する円筒状のモータ軸３４とを備える。モータ軸３４は、ハブ軸１１外周に一対のモータ軸支持用第１，第２軸受Ｂ５，Ｂ５′を介して回転自在に嵌合、支持される。 The motor M includes, for example, a bottomed cylindrical motor case 31 that is open at one end 31 a and faces the end wall member He, a stator 32 that is fixed to the inner peripheral surface of the body portion of the motor case 31, and the radial direction of the stator 32. A rotor 33 with a permanent magnet disposed on the inner side and a cylindrical motor shaft 34 for fixing the rotor 33 to the outer peripheral portion are provided. The motor shaft 34 is rotatably fitted and supported on the outer periphery of the hub shaft 11 via a pair of motor shaft support first and second bearings B5 and B5 '.
　モータケース３１の底壁となる端壁部３１ｂの、ボス状をなす内周部は、例えばハブ軸１１の外周に嵌合固定（本実施形態では圧入）したボス部材３５の外周に嵌合固定（本実施形態ではスプライン圧入）される。尚、本実施形態とは異なる固定手段（例えば、スプラインと止め輪の併用、螺合等）により、端壁部３１ｂの内周部をハブ軸１１外周に固定してもよい。 A boss-like inner peripheral portion of the end wall portion 31b that becomes the bottom wall of the motor case 31 is fitted and fixed to the outer periphery of a boss member 35 that is fitted and fixed to the outer periphery of the hub shaft 11 (press-fit in this embodiment), for example. (In this embodiment, spline press-fitting). Note that the inner peripheral portion of the end wall portion 31b may be fixed to the outer periphery of the hub shaft 11 by a fixing means (for example, combined use of a spline and a retaining ring, screwing or the like) different from the present embodiment.
　またモータケース３１の端壁部３１ｂ外面には、モータＭ（より具体的にはステータ３２のコイル部）への通電制御を行う電子制御装置ＥＣＵが付設される。電子制御装置ＥＣＵから延びる配線は、ハブ支持リング１５ｒの貫通孔を通して外部に引き出される。尚、その配線は、図示しない踏力検出手段や車載バッテリ等に接続される。 Further, on the outer surface of the end wall portion 31b of the motor case 31, an electronic control unit ECU for controlling energization to the motor M (more specifically, the coil portion of the stator 32) is attached. The wiring extending from the electronic control unit ECU is drawn out through the through hole of the hub support ring 15r. Note that the wiring is connected to a pedaling force detection means, an in-vehicle battery or the like (not shown).
　次に減速機構部Ｒの一例を説明する。減速機構部Ｒは、モータＭにより回転駆動される減速サンギヤ５１と、減速サンギヤ５１に噛合する第１ギヤ５２ａ、及び第１ギヤ５２ａに対し小径且つ同軸に並ぶ第２ギヤ５２ｂを一体的に結合してなる複数の減速遊星ギヤ５２と、減速遊星ギヤ５２を回転自在に支持する減速キャリア５３と、モータケース３１の一端部３１ａに嵌着されて第１ギヤ５２ａに噛合する第１減速リングギヤ５４と、第２ギヤ５２ｂに噛合する第２減速リングギヤ５５とを備える。 Next, an example of the deceleration mechanism R will be described. The reduction mechanism R integrally couples a reduction sun gear 51 that is rotationally driven by the motor M, a first gear 52a that meshes with the reduction sun gear 51, and a second gear 52b that is arranged coaxially with the first gear 52a. A plurality of reduction planetary gears 52, a reduction carrier 53 that rotatably supports the reduction planetary gear 52, and a first reduction ring gear 54 that is fitted to one end 31a of the motor case 31 and meshes with the first gear 52a. And a second reduction ring gear 55 that meshes with the second gear 52b.
　減速サンギヤ５１は、後述する減速キャリア支持用第１軸受Ｂ６に隣接してハブ軸１１外周に圧入、固定される。尚、減速サンギヤ５１の固定手段としては、本実施形態とは異なる固定手段、例えば溶接、カシメ、接着、スプライン嵌合及び止め輪の併用等を採用してもよい。 The reduction sun gear 51 is press-fitted and fixed to the outer periphery of the hub shaft 11 adjacent to a reduction carrier supporting first bearing B6 described later. In addition, as a fixing means of the reduction sun gear 51, a fixing means different from the present embodiment, for example, welding, caulking, adhesion, spline fitting, and a combined use of a retaining ring may be employed.
　減速キャリア５３は、各々の減速遊星ギヤ５２を回転自在に貫通、支持する減速キャリア軸５６と、減速キャリア軸５６の一端部を固定する第１側壁部ｓ１を有する第１キャリア半体５３ａと、第１側壁部ｓ１との間に減速遊星ギヤ５２を挟み且つ減速キャリア軸５６の他端部を固定する第２側壁部ｓ２を有する第２キャリア半体５３ｂとを備える。第１キャリア半体５３ａは、複数の連結腕部５３ａｕを一体に有しており、連結腕部５３ａｕの先部が、第２キャリア半体５３ｂに固定される。 The reduction carrier 53 includes a reduction carrier shaft 56 that rotatably penetrates and supports each reduction planetary gear 52, a first carrier half 53a having a first side wall portion s1 that fixes one end of the reduction carrier shaft 56, and A second carrier half 53b having a second side wall portion s2 that sandwiches the reduction planetary gear 52 between the first side wall portion s1 and fixes the other end portion of the reduction carrier shaft 56; The first carrier half 53a integrally has a plurality of connecting arm portions 53au, and the tip of the connecting arm portion 53au is fixed to the second carrier half 53b.
　第１側壁部ｓ１は、第１キャリア半体５３ａの内周及びモータ軸３４の対向周面間に介装した減速キャリア支持用第１軸受Ｂ６を介してモータ軸３４（従ってモータ軸３４を介してハブ軸１１）に回転自在に支持される。一方、第２側壁部ｓ２は、第２キャリア半体５３ｂの内周及びハブ軸１１の対向周面間に介装した減速キャリア支持用第２軸受Ｂ６′を介してハブ軸１１に回転自在に支持される。尚、ハブ軸１１外周には、減速キャリア支持用第２軸受Ｂ６′のインナレースに係合して第２軸受Ｂ６′（従って減速キャリア５３）をハブ軸１１上に保持するための固定リング５７が嵌着（例えば圧入）される。 The first side wall portion s1 is connected to the motor shaft 34 (and thus via the motor shaft 34) via the first carrier B6 for speed reduction carrier support interposed between the inner periphery of the first carrier half 53a and the opposed peripheral surface of the motor shaft 34. The hub shaft 11) is rotatably supported. On the other hand, the second side wall portion s2 is rotatable on the hub shaft 11 via the second carrier B6 ′ for supporting the speed reduction carrier interposed between the inner periphery of the second carrier half 53b and the opposed peripheral surface of the hub shaft 11. Supported. On the outer periphery of the hub shaft 11, a fixing ring 57 for engaging the inner race of the second bearing B 6 ′ for supporting the deceleration carrier and holding the second bearing B 6 ′ (and hence the deceleration carrier 53) on the hub shaft 11. Is inserted (for example, press-fitted).
　第１減速リングギヤ５４は、第１ギヤ５２ａと噛合する内歯５４ｍｇを有するリングギヤ本体部５４ｍと、リングギヤ本体部５４ｍから軸方向でモータケース３１外に延出するリングギヤ延出部５４ａとを一体に有する。 The first reduction ring gear 54 is integrally formed with a ring gear main body portion 54m having an inner tooth 54mg that meshes with the first gear 52a and a ring gear extension portion 54a that extends from the ring gear main body portion 54m to the outside of the motor case 31 in the axial direction. Have.
　ところで端壁部材Ｈｅ、特に第２端壁部材半体Ｈｅ２の軸方向内側面には、軸方向内方側に延出してハブケース本体Ｈｍ内周に嵌合する円筒状の外側延出部６１が一体に突設され、また第２端壁部材半体Ｈｅ２の軸方向内側面の内周部には、軸方向内方側に延出し且つ外側延出部６１により同心状に囲繞される円筒状の内側延出部６２が一体に突設される。そして、第１減速リングギヤ５４のリングギヤ延出部５４ａが、外側延出部６１及び内側延出部６２の相互間に画成される環状空隙に突入している。 By the way, on the inner side surface in the axial direction of the end wall member He, particularly the second end wall member half body He2, there is a cylindrical outer extending portion 61 that extends inward in the axial direction and fits into the inner periphery of the hub case body Hm. A cylindrical shape projecting integrally and extending inward in the axial direction and concentrically surrounded by an outer extending portion 61 on the inner peripheral portion of the inner end surface in the axial direction of the second end wall member half body He <b> 2. The inner extending portion 62 is integrally projected. The ring gear extension 54 a of the first reduction ring gear 54 enters an annular gap defined between the outer extension 61 and the inner extension 62.
　またリングギヤ延出部５４ａの内周と内側延出部６２の外周との間には、第１減速リングギヤ５４をハブケースＨ（より具体的には第２端壁部材半体Ｈｅ２）を介して回転自在に支持させる第１減速リングギヤ支持用軸受Ｂ７が介装される。従って、リングギヤ延出部５４ａの内周面が上記軸受Ｂ７の第１減速リングギヤ５４側の取付面となる。 Further, between the inner periphery of the ring gear extension 54a and the outer periphery of the inner extension 62, the first reduction ring gear 54 is rotated via the hub case H (more specifically, the second end wall member half body He2). A first reduction ring gear support bearing B7 to be freely supported is interposed. Accordingly, the inner peripheral surface of the ring gear extending portion 54a becomes the mounting surface on the first reduction ring gear 54 side of the bearing B7.
　而して、モータＭに駆動される減速サンギヤ５１の回転が減速遊星ギヤ５２の第１ギヤ５２ａに伝えられると、第１減速リングギヤ５４がモータケース３１に固定されていることから、減速キャリア５３に回転可能に支持された減速遊星ギヤ５２がハブ軸１１回りを公転しながら減速キャリア軸５６回りに自転する。そして、この減速遊星ギヤ５２の公転及び自転が第２ギヤ５２ｂから第２減速リングギヤ５５に伝達されることで、後述するように、駆動用電動モータ４の回転をハブケースＨに高い減速比で伝達可能となる。 Thus, when the rotation of the reduction sun gear 51 driven by the motor M is transmitted to the first gear 52 a of the reduction planetary gear 52, the first reduction ring gear 54 is fixed to the motor case 31. The reduction planetary gear 52 supported so as to rotate freely rotates around the reduction carrier shaft 56 while revolving around the hub shaft 11. Then, the revolution and rotation of the reduction planetary gear 52 are transmitted from the second gear 52b to the second reduction ring gear 55, so that the rotation of the drive electric motor 4 is transmitted to the hub case H at a high reduction ratio, as will be described later. It becomes possible.
　次に、第１実施形態の作用を説明する。電動補助自転車の走行中、搭乗者によるペダルの踏力は、変速機構部Ｔを介して二段階（第１速又は第２速）に変速されて端壁部材Ｈｅ、従ってハブケースＨに伝達される。 Next, the operation of the first embodiment will be described. During the travel of the battery-assisted bicycle, the pedaling force of the pedal by the occupant is shifted in two stages (first speed or second speed) via the speed change mechanism T and transmitted to the end wall member He and thus the hub case H.
　例えば、シフト機構Ｓの操作ドラム４３がアンロック位置に在って、変速サンギヤ２３とハブ軸１１間の接続が解除されているときは、変速キャリア２２の回転が第２ワンウェイクラッチＣ２、変速リングギヤ２５、第１ワンウェイクラッチＣ１を経て直接、端壁部材Ｈｅに伝達される。これにより、後輪の一部であるハブケースＨが変速キャリア２２と同じ回転数で回転する。 For example, when the operation drum 43 of the shift mechanism S is in the unlocked position and the connection between the transmission sun gear 23 and the hub shaft 11 is released, the rotation of the transmission carrier 22 is rotated by the second one-way clutch C2, the transmission ring gear. 25, directly transmitted to the end wall member He via the first one-way clutch C1. As a result, the hub case H that is a part of the rear wheel rotates at the same rotational speed as that of the transmission carrier 22.
　一方、シフト機構Ｓの操作ドラム４３がロック位置に在って、変速サンギヤ２３がハブ軸１１に固定されているときは、変速キャリア２２の回転が変速遊星ギヤ２４及び変速リングギヤ２５を経て増速されて端壁部材Ｈｅに伝達される。これにより、ハブケースＨが、変速キャリア２２の回転に対し増速されて回転する。 On the other hand, when the operation drum 43 of the shift mechanism S is in the locked position and the transmission sun gear 23 is fixed to the hub axle 11, the rotation of the transmission carrier 22 is increased through the transmission planetary gear 24 and the transmission ring gear 25. And transmitted to the end wall member He. As a result, the hub case H rotates at an increased speed relative to the rotation of the transmission carrier 22.
　尚、変速キャリア２２及び変速リングギヤ２５間には第２ワンウェイクラッチＣ２が、また変速リングギヤ２５及び端壁部材Ｈｅ間には第１ワンウェイクラッチＣ１がそれぞれ介装されるため、例えば、下り坂において、ペダルの回転が遅くハブケースＨの回転が速い場合でも、ハブケースＨの回転がペダル側に伝達されることはない。 The second one-way clutch C2 is interposed between the transmission carrier 22 and the transmission ring gear 25, and the first one-way clutch C1 is interposed between the transmission ring gear 25 and the end wall member He. Even when the pedal rotation is slow and the hub case H is fast, the rotation of the hub case H is not transmitted to the pedal side.
　また、電動補助自転車の走行中、図示しない負荷検出手段により後輪の走行負荷増大が検出されると、電子制御装置ＥＣＵからモータＭに通電がなされ、モータ軸３４の回転が減速機構部Ｒを経て十分に減速されて端壁部材Ｈｅ従ってハブケースＨに伝達される。これにより、踏力不足がモータＭの駆動力で補助されるため、例えば、登り坂でも無理なく走行可能となる。 Further, when the rear wheel driving load increase is detected by a load detection means (not shown) while the battery-assisted bicycle is traveling, the motor M is energized from the electronic control unit ECU, and the rotation of the motor shaft 34 causes the speed reduction mechanism R to be After that, it is sufficiently decelerated and transmitted to the end wall member He and therefore to the hub case H. As a result, insufficient pedaling force is assisted by the driving force of the motor M, so that it is possible to travel without difficulty even on an uphill.
　また本実施形態の変速機構部Ｔにおいては、端壁部材Ｈｅ及び変速リングギヤ２５間に介装した第１ワンウェイクラッチＣ１と、変速リングギヤ２５及び変速キャリア２２間に介装した第２ワンウェイクラッチＣ２とが、互いに軸方向にずれた位置で変速リングギヤ２５上（より具体的には変速リングギヤ本体２５ｍ及びリングギヤ延出部２５ａの各外周面）に直列配置され、更に変速キャリア２２と端壁部材Ｈｅ間に介装されるハブ支持用第２軸受Ｂ２が、第２ワンウェイクラッチＣ２の大部分と軸方向で同一位置となる（即ち径方向にオーバラップする）ようにして第２ワンウェイクラッチＣ２の周囲を取り囲む配置となっている。これにより、第１，第２ワンウェイクラッチＣ１，Ｃ２、並びにハブ支持用第２軸受Ｂ２の三者が軸方向に並ぶ従来構造に比べて変速機構部Ｔが軸方向に小型化されるため、それだけ動力ユニットＵの小型化が達成される。 In the transmission mechanism T of the present embodiment, the first one-way clutch C1 interposed between the end wall member He and the transmission ring gear 25, and the second one-way clutch C2 interposed between the transmission ring gear 25 and the transmission carrier 22; Are arranged in series on the transmission ring gear 25 (more specifically, the outer peripheral surfaces of the transmission ring gear main body 25m and the ring gear extension 25a) at positions shifted in the axial direction, and further between the transmission carrier 22 and the end wall member He. The second bearing B2 for supporting the hub interposed between the second one-way clutch C2 and the second one-way clutch C2 is positioned so as to be in the same position in the axial direction (that is, overlaps in the radial direction) with the majority of the second one-way clutch C2. Surrounding arrangement. As a result, the transmission mechanism T is reduced in the axial direction compared to the conventional structure in which the first and second one-way clutches C1 and C2 and the hub supporting second bearing B2 are arranged in the axial direction. Miniaturization of the power unit U is achieved.
　また第１，第２ワンウェイクラッチＣ１，Ｃ２が、上記のように変速リングギヤ２５上に直列配置される一方で、ハブケースＨの一端壁部、即ち端壁部材Ｈｅには、モータ駆動系ＭＤからの動力が入力される被動部（より具体的には第２端壁部材半体Ｈｅ２の内側延出部６２）が設けられる。これにより、端壁部材Ｈｅが動力を受ける被動部としては、モータ駆動系ＭＤからの被動部（第２端壁部材半体Ｈｅ２の内側延出部６２）と第１ワンウェイクラッチＣ１からの被動部（第１端壁部材半体Ｈｅ１の内周ボス部６３）しかなく、それだけ端壁部材Ｈｅの小型化や構造簡素化が図られ、延いては動力ユニットＵの小型化が図られる。 The first and second one-way clutches C1 and C2 are arranged in series on the transmission ring gear 25 as described above, while one end wall portion of the hub case H, that is, the end wall member He is provided from the motor drive system MD. A driven portion to which power is input (more specifically, the inner extending portion 62 of the second end wall member half body He2) is provided. As a result, the driven portion from which the end wall member He receives power includes the driven portion from the motor drive system MD (the inner extending portion 62 of the second end wall member half body He2) and the driven portion from the first one-way clutch C1. There is only (the inner peripheral boss portion 63 of the first end wall member half body He1), so that the end wall member He can be reduced in size and structure, and the power unit U can be further reduced in size.
　また変速リングギヤ２５は、変速遊星ギヤ２４と噛合する内歯２５ｍｇを有するリングギヤ本体部２５ｍと、リングギヤ本体部２５ｍから軸方向外方に延びるリングギヤ延出部２５ａとを有しており、第２ワンウェイクラッチＣ２がリングギヤ延出部２５ａの外周とキャリア延出部２２Ｂａの内周との間に介装される。これにより、第１，第２ワンウェイクラッチＣ１，Ｃ２の軸方向合計幅が変速遊星ギヤ２４の歯幅より長くても、両クラッチＣ１，Ｃ２を、互いに軸方向に隣接させた状態で変速リングギヤ２５上に無理なく直列配置可能となる。 The transmission ring gear 25 includes a ring gear main body portion 25m having an inner tooth 25mg meshing with the transmission planetary gear 24, and a ring gear extending portion 25a extending axially outward from the ring gear main body portion 25m. The clutch C2 is interposed between the outer periphery of the ring gear extension 25a and the inner periphery of the carrier extension 22Ba. As a result, even if the total axial width of the first and second one-way clutches C1 and C2 is longer than the tooth width of the transmission planetary gear 24, both the clutches C1 and C2 are axially adjacent to each other, and the transmission ring gear 25 Can be placed in series without difficulty.
　更にリングギヤ延出部２５ａの内周と変速キャリア２２との対向周面間には変速リングギヤ支持用軸受Ｂ４が介装されており、この変速リングギヤ支持用軸受Ｂ４は、第２ワンウェイクラッチＣ２の大部分と軸方向で同一位置に配置される。これにより、変速リングギヤ２５は、これが第１，第２ワンウェイクラッチＣ１，Ｃ２の前記した直列配置に伴い軸方向に長くなっても、変速リングギヤ支持用軸受Ｂ４を介して変速キャリア２２に安定よく支持されるから、変速遊星ギヤ２４との歯当たりも良好であり、変速遊星ギヤ２４がスムーズ且つ静粛に回転可能となる。しかも変速リングギヤ支持用軸受Ｂ４は、これがリングギヤ延出部２５ａと径方向に一部オーバラップすることで、該軸受Ｂ４の軸方向張出しが抑えられることから、動力ユニットＵの軸方向小型化が図られる。 Further, a transmission ring gear support bearing B4 is interposed between the inner periphery of the ring gear extension 25a and the opposed peripheral surface of the transmission carrier 22, and this transmission ring gear support bearing B4 is a large one of the second one-way clutch C2. Arranged in the same position in the axial direction as the part. As a result, the transmission ring gear 25 is stably supported on the transmission carrier 22 via the transmission ring gear support bearing B4 even if the transmission ring gear 25 becomes longer in the axial direction due to the series arrangement of the first and second one-way clutches C1 and C2. Therefore, the tooth contact with the speed change planetary gear 24 is good, and the speed change planetary gear 24 can rotate smoothly and quietly. Moreover, since the transmission ring gear support bearing B4 partially overlaps the ring gear extension 25a in the radial direction, the axial extension of the bearing B4 is suppressed, so that the power unit U can be downsized in the axial direction. It is done.
　また、本実施形態の減速機構部Ｒにおいては、減速遊星ギヤ５２が同軸に並ぶ第１，第２ギヤ５２ａ，５２ｂを有し、第１ギヤ５２ａに噛合する第１減速リングギヤ５４が有底筒状のモータケース３１の一端部３１ａに嵌着され、第２ギヤ５２ｂに噛合する第２減速リングギヤ５５が端壁部材Ｈｅ（より具体的には第２端壁部材半体Ｈｅ２の内側延出部６２の内周）に設けられ、第１減速リングギヤ５４と、端壁部材Ｈｅ（より具体的には上記内側延出部６２の外周）との間には、第１減速リングギヤ支持用軸受Ｂ７が介装される。これにより、減速機構部Ｒは、高い減速比を確保しながらも、その減速比確保のための第１，第２減速リングギヤ５４，５５の支持剛性が、端壁部材Ｈｅを活用して十分に確保可能である。 In the speed reduction mechanism R of the present embodiment, the reduction planetary gear 52 has first and second gears 52a and 52b arranged coaxially, and the first reduction ring gear 54 meshed with the first gear 52a is a bottomed cylinder. The second reduction ring gear 55 fitted to the one end 31a of the motor case 31 and meshed with the second gear 52b is connected to the end wall member He (more specifically, the inner extension of the second end wall member half He2). 62, and a first reduction ring gear support bearing B7 is provided between the first reduction ring gear 54 and the end wall member He (more specifically, the outer periphery of the inner extension 62). Intervened. As a result, the speed reduction mechanism R has sufficient support rigidity of the first and second speed reduction ring gears 54 and 55 for securing the speed reduction ratio while ensuring a high speed reduction ratio by utilizing the end wall member He. It can be secured.
　特に第１減速リングギヤ５４は、これがモータケース３１の一端部３１ａ、即ち自由端部（開放端部）に固定されていて、ハブ軸１１に対しては片持ち支持形態であるが、この第１減速リングギヤ５４のリングギヤ延出部５４ａを、第１減速リングギヤ支持用軸受Ｂ７を介して端壁部材Ｈｅに支持させたことで、第１減速リングギヤ５４が実質的に両持ち支持形態となって支持が安定し、軸ずれ防止に有効である。従って、第１減速リングギヤ５４にモータＭの回転振動が直接伝達されても、第１減速リングギヤ５４の振動を極力抑制できるため、第１減速リングギヤ５４と減速遊星ギヤ５２（より具体的には第１ギヤ５２ａ）との噛合部の歯当たりを良好にして耐久性を高めることができ、また噛合部からの騒音の発生を低減可能となる。 In particular, the first reduction ring gear 54 is fixed to one end 31 a of the motor case 31, that is, a free end (open end), and is in a cantilevered form with respect to the hub shaft 11. The ring gear extension 54a of the reduction ring gear 54 is supported by the end wall member He via the first reduction ring gear support bearing B7, so that the first reduction ring gear 54 is supported in a substantially doubly supported form. Is stable and effective in preventing shaft misalignment. Therefore, even if the rotational vibration of the motor M is directly transmitted to the first reduction ring gear 54, the vibration of the first reduction ring gear 54 can be suppressed as much as possible. Therefore, the first reduction ring gear 54 and the reduction planetary gear 52 (more specifically, the first reduction ring gear 54). It is possible to improve the durability by making the contact of the meshing portion with the 1 gear 52a) good, and to reduce the generation of noise from the meshing portion.
　また上記のようにモータケース３１の一端部３１ａを第１減速リングギヤ５４及び第１減速リングギヤ支持用軸受Ｂ７を介してハブケースＨ側に支持させたことで、ハブ軸１１にモータケース３１の一端部３１ａ側を支持させる必要はなくなり、それに伴い、ハブ軸１１周囲にスペースの余裕が生じる。そして、本実施形態では、このスペースを利用して、減速キャリア５３の両側壁部ｓ１，ｓ２（第１，第２キャリア半体５３ａ，５３ｂ）を減速キャリア支持用第１，第２軸受Ｂ６，Ｂ６′を介してハブ軸１１上に支持するため、軸方向に幅広の減速キャリア５３を、軸方向に長い支持スパンを以て両持ち支持可能となる。これにより、動力ユニットＵの小型化を図りながら減速キャリア５３の安定支持が図られる。 Further, as described above, the one end portion 31a of the motor case 31 is supported on the hub case H side via the first reduction ring gear 54 and the first reduction ring gear support bearing B7. It is not necessary to support the 31a side, and accordingly, there is a space around the hub shaft 11. In this embodiment, by using this space, both side walls s1, s2 (first and second carrier halves 53a, 53b) of the speed reduction carrier 53 are connected to the speed reduction carrier supporting first and second bearings B6, B6. Since it is supported on the hub axle 11 via B6 ', the deceleration carrier 53 that is wide in the axial direction can be supported at both ends with a long support span in the axial direction. Thereby, the stable support of the deceleration carrier 53 is achieved, aiming at size reduction of the power unit U.
　さらに本実施形態の第１減速リングギヤ５４は、モータケース３１の一端部３１ａよりモータケース３１外に軸方向に延出するリングギヤ延出部５４ａを一体に有していて、このリングギヤ延出部５４ａの周面が、第１減速リングギヤ支持用軸受Ｂ７の取付面とされているため、モータケース３１自体を特別に大径化しなくても十分な軸受径を確保可能となる。 Further, the first reduction ring gear 54 of the present embodiment integrally has a ring gear extension 54a that extends in the axial direction from the one end 31a of the motor case 31 to the outside of the motor case 31, and this ring gear extension 54a. Since the peripheral surface is the mounting surface of the first reduction ring gear support bearing B7, a sufficient bearing diameter can be secured without specially increasing the diameter of the motor case 31 itself.
第２の実施の形態Second embodiment
　次に、図６に基づいて、本発明の第２実施形態を説明する。第２実施形態では、第１減速リングギヤ支持用軸受Ｂ７が、第１減速リングギヤ５４のリングギヤ延出部５４ａ′の外周と第２端壁部材半体Ｈｅ２の外側延出部６１′の内周との間に介装されていて、リングギヤ延出部５４ａ′の外周面及び外側延出部６１′の内周面が第１減速リングギヤ支持用軸受Ｂ７の取付面となる点だけが、第１実施形態と相違する。 Next, a second embodiment of the present invention will be described based on FIG. In the second embodiment, the first reduction ring gear support bearing B7 includes the outer periphery of the ring gear extension 54a 'of the first reduction ring gear 54 and the inner periphery of the outer extension 61' of the second end wall member half body He2. In the first embodiment, only the outer peripheral surface of the ring gear extension 54a 'and the inner peripheral surface of the outer extension 61' serve as the mounting surface of the first reduction ring gear support bearing B7. It differs from the form.
　第２実施形態の電動補助自転車用動力ユニットＵのその他の構成は、第１実施形態の動力ユニットＵと同じであるので、図６において各構成要素には、第１実施形態の対応する構成要素と同じ参照符号を付すにとどめ、これ以上の構造説明は省略する。而して、第２実施形態においても、第１実施形態と同様の作用効果が期待できる。 Since the other configuration of the power assisted bicycle power unit U of the second embodiment is the same as that of the power unit U of the first embodiment, each component in FIG. 6 corresponds to the corresponding component of the first embodiment. Only the same reference numerals are attached, and further description of the structure is omitted. Thus, also in the second embodiment, the same effect as the first embodiment can be expected.
第３の実施の形態Third embodiment
　次に、図７に基づいて、本発明の第３実施形態を説明する。第１，第２実施形態では、端壁部材Ｈｅの軸方向内側面に各々突設した外側延出部６１，６１′及び内側延出部６２，６２′の対向周面間に環状空隙を画成し、その環状空隙に第１減速リングギヤ５４のリングギヤ延出部５４ａ，５４ａ′を突入させ、その環状空隙に臨むリングギヤ延出部５４ａ，５４ａ′の周面を第１減速リングギヤ支持用軸受Ｂ７の取付面としている。 Next, a third embodiment of the present invention will be described based on FIG. In the first and second embodiments, an annular gap is defined between the opposed peripheral surfaces of the outer extending portions 61 and 61 ′ and the inner extending portions 62 and 62 ′ that protrude from the inner side surface in the axial direction of the end wall member He. The ring gear extension portions 54a and 54a 'of the first reduction ring gear 54 are inserted into the annular gap, and the circumferential surfaces of the ring gear extension portions 54a and 54a' facing the annular gap are provided with the first reduction ring gear support bearing B7. The mounting surface.
　これに対し第３実施形態では、端壁部材Ｈｅの軸方向内側面に突設した外側延出部６１″の内周側に内側延出部６２″を一体に連設して、内側延出部６２″（従って第２減速リングギヤ５５）の剛性強度を高めており、また第１減速リングギヤ５４のリングギヤ延出部５４ａ″の延出端が内側延出部６２″の延出端と対向近接している。 On the other hand, in the third embodiment, an inner extending portion 62 ″ is integrally connected to the inner peripheral side of the outer extending portion 61 ″ projecting on the inner side surface in the axial direction of the end wall member He to extend the inner side. The rigidity of the portion 62 ″ (and hence the second reduction ring gear 55) is increased, and the extension end of the ring gear extension 54a ″ of the first reduction ring gear 54 is opposed to the extension end of the inner extension 62 ″. is doing.
　第３実施形態の電動補助自転車用動力ユニットＵのその他の構成は、第２実施形態の動力ユニットＵと同じであるので、図７において各構成要素には、第２実施形態の対応する構成要素と同じ参照符号を付すにとどめ、これ以上の構造説明は省略する。而して、第３実施形態においても、第１，第２実施形態と同様の作用効果が期待できる。 Other configurations of the power unit U for the battery-assisted bicycle according to the third embodiment are the same as those of the power unit U according to the second embodiment. Therefore, in FIG. 7, each component is a corresponding component of the second embodiment. Only the same reference numerals are attached, and further description of the structure is omitted. Thus, also in the third embodiment, the same operational effects as those in the first and second embodiments can be expected.
　以上、本発明の第１～第３実施形態を説明したが、本発明はその要旨を逸脱しない範囲で種々の設計変更を行うことが可能である。 The first to third embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.
　例えば、前記実施形態では、動力ユニットＵを後輪に配置しているが、これを前輪に配置することもできる。 For example, in the above-described embodiment, the power unit U is disposed on the rear wheel, but this can also be disposed on the front wheel.
　また前記実施形態では、動力ユニットＵを搭載した車両が電動補助自転車であるものについて説明したが、本発明の動力ユニットは、足踏み式の電動補助三，四輪車にも適用可能である。 In the above-described embodiment, the vehicle on which the power unit U is mounted is described as a battery-assisted bicycle. However, the power unit of the present invention can also be applied to a stepping-type battery-assisted three-wheeled vehicle.
　また前記実施形態では、動力ユニットＵを搭載した車両が、車輪の駆動に電動と人力（足踏み入力）とを併用した電動補助車両（即ち電動補助自転車、電動補助三，四輪車）であるものについて説明したが、本発明は、車輪を専ら電動で駆動するタイプの電動車両（例えば電動二輪車や電動三，四輪車）にも適用可能である。 In the above embodiment, the vehicle equipped with the power unit U is an electrically assisted vehicle (that is, an electrically assisted bicycle, an electrically assisted tricycle, and a four wheel vehicle) that uses both electric power and human power (stepping input) for driving wheels. However, the present invention can also be applied to an electric vehicle of a type in which wheels are exclusively driven electrically (for example, an electric motorcycle, an electric three-wheeled vehicle, and the like).
　また前記実施形態には示されていないが、モータＭの引きずりを防止するためにハブケースＨ（端壁部材Ｈｅ）と第２減速リングギヤ５５との間に、第２減速リングギヤ５５からハブケースＨ側へのみ動力を伝達するワンウェイクラッチを配置してもよい。 Although not shown in the embodiment, in order to prevent the motor M from dragging, the second reduction ring gear 55 is moved from the second reduction ring gear 55 to the hub case H side between the hub case H (end wall member He) and the second reduction ring gear 55. A one-way clutch that transmits power only may be arranged.

Claims (3)

  1. 　車輪のハブケース（Ｈ）の一端壁部（Ｈｅ）及び他端壁部（Ｈｍｂ）がハブ軸（１１）に各々回転可能に支持されると共に、該ハブケース（Ｈ）に、モータ（Ｍ）と、前記モータ（Ｍ）の駆動力を減速して該ハブケース（Ｈ）に伝達する減速機構部（Ｒ）とが軸方向に並んで収容され、
    　前記モータ（Ｍ）は、一端部（３１ａ）が開放し且つ前記ハブケース（Ｈ）の前記一端壁部（Ｈｅ）に対向する有底筒状のモータケース（３１）を有すると共に、該モータケース（３１）の底部となる他端部（３１ｂ）が前記ハブ軸（１１）に固定、支持される電動車両用動力ユニットであって、
    　前記減速機構部（Ｒ）は、前記モータ（Ｍ）により回転駆動される減速サンギヤ（５１）と、前記減速サンギヤ（５１）に噛合する第１ギヤ（５２ａ）、及び該第１ギヤ（５２ａ）に対し同軸に並ぶ第２ギヤ（５２ｂ）を回転自在に支持する減速キャリア（５３）と、前記モータケース（３１）の前記一端部（３１ａ）に嵌着されて前記第１ギヤ（５２ａ）に噛合する第１減速リングギヤ（５４）と、前記ハブケース（Ｈ）に設けられて前記第２ギヤ（５２ｂ）に噛合する第２減速リングギヤ（５５）とを備えており、
    　前記第１減速リングギヤ（５４）と前記ハブケース（Ｈ）との間には、該第１減速リングギヤ（５４）を該ハブケース（Ｈ）に回転自在に支持させる軸受（Ｂ７）が介装されることを特徴とする、電動車両用動力ユニット。     One end wall portion (He) and the other end wall portion (Hmb) of the wheel hub case (H) are rotatably supported by the hub shaft (11), and the hub case (H) includes a motor (M), A speed reduction mechanism (R) that decelerates the driving force of the motor (M) and transmits it to the hub case (H) is housed side by side in the axial direction,
    The motor (M) has a bottomed cylindrical motor case (31) that is open at one end (31a) and faces the one end wall (He) of the hub case (H). 31) is a power unit for an electric vehicle in which the other end portion (31b) serving as the bottom portion is fixed and supported on the hub shaft (11),
    The reduction mechanism (R) includes a reduction sun gear (51) that is rotationally driven by the motor (M), a first gear (52a) that meshes with the reduction sun gear (51), and the first gear (52a). A reduction carrier (53) that rotatably supports the second gear (52b) arranged coaxially with the first gear (52a) is fitted to the one end (31a) of the motor case (31). A first reduction ring gear (54) that meshes with a second reduction ring gear (55) that is provided on the hub case (H) and meshes with the second gear (52b);
    A bearing (B7) for rotatably supporting the first reduction ring gear (54) on the hub case (H) is interposed between the first reduction ring gear (54) and the hub case (H). A power unit for an electric vehicle.
  2. 　前記減速キャリア（５３）の、前記第１，第２ギヤ（５２ａ，５２ｂ）を軸方向に挟む両側壁部（ｓ１，ｓ２）がそれぞれ前記ハブ軸（１１）上に回転自在に支持されることを特徴とする、請求項１に記載の電動車両用動力ユニット。 Both side wall portions (s1, s2) of the deceleration carrier (53) sandwiching the first and second gears (52a, 52b) in the axial direction are rotatably supported on the hub shaft (11), respectively. The power unit for an electric vehicle according to claim 1, characterized in that:
  3. 　前記第１減速リングギヤ（５４）は、前記モータケース（３１）の前記一端部（３１ａ）より該モータケース（３１）外に軸方向に延出するリングギヤ延出部（５４ａ，５４ａ′，５４ａ″）を一体に有していて、該リングギヤ延出部（５４ａ，５４ａ′，５４ａ″）の外周面又は内周面が前記軸受（Ｂ７）の、前記第１減速リングギヤ（５４）側の取付面とされることを特徴とする、請求項１又は２に記載の電動車両用動力ユニット。 The first reduction ring gear (54) includes ring gear extension portions (54a, 54a ′, 54a ″) that extend in the axial direction from the one end portion (31a) of the motor case (31) to the outside of the motor case (31). ), And the outer peripheral surface or inner peripheral surface of the ring gear extension (54a, 54a ′, 54a ″) is the mounting surface of the bearing (B7) on the first reduction ring gear (54) side. The power unit for an electric vehicle according to claim 1, wherein the power unit is for electric vehicles.
PCT/JP2018/008022 2017-03-23 2018-03-02 Power unit for electric vehicle WO2018173696A1 (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5166967A (en) * 1974-10-29 1976-06-10 Eaton Corp
JPS6275152A (en) * 1985-09-30 1987-04-07 Toshiba Corp Differential planetary gear device
JP2012241821A (en) * 2011-05-20 2012-12-10 Ntn Corp Electric vehicle reduction differential gear

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5166967A (en) * 1974-10-29 1976-06-10 Eaton Corp
JPS6275152A (en) * 1985-09-30 1987-04-07 Toshiba Corp Differential planetary gear device
JP2012241821A (en) * 2011-05-20 2012-12-10 Ntn Corp Electric vehicle reduction differential gear

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