JP2017047731A - Electric assist bicycle speed reducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify and downsize a structure of an electric assist bicycle drive unit with a speed reduction mechanism.SOLUTION: There is provided an electric assist bicycle drive unit, including: a crank shaft 2 accommodated in a casing 1, and to which threading force is inputted; a motor 3 for outputting driving force; a threading force transmission mechanism 40 to which rotations of the crank shaft 2 are transmitted; a resultant force output unit 5 for summing rotations of the threading force transmission mechanism 40 and output of the motor 3 and transmitting the same to a driving wheel 52; and a speed reduction mechanism 20 provided between the motor 3 and the resultant force output unit 5. In the drive unit, the speed reduction mechanism 20 is a roller speed reducing machine including, in a motor input member 11 to be rotated by the output of the motor 3, one bearing ring 12, and the other bearing ring 13 opposing to the one bearing ring 12, and including a driving force transmission member 31 disposing a plurality of planetary members 21 along the circumferential direction between the one bearing ring 12 and the other bearing ring 13, holding the same by a carrier 22 to transmit the rotations of the carrier 22 following revolutions of each planetary member 21 to the resultant force output unit 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a reduction gear used for a battery-assisted bicycle.

  In recent years, electrically assisted bicycles that travel by synthesizing the driving force generated by the pedaling force received by the pedal and the driving force output from the motor as auxiliary power and transmitting the combined driving force to the driving wheels have become widespread. Yes.

  In this battery-assisted bicycle, for example, as shown in Patent Document 1, a crankshaft that is rotated by a treading force, a motor that is arranged coaxially with the crankshaft, a space away from the crankshaft, and the rotation of the crankshaft is provided. There is a type including a drive unit including a power transmission shaft to be transmitted and an output unit to which the rotation of the power transmission shaft is transmitted and the output of the motor is added.

  This drive unit includes a two-stage planetary reduction mechanism and a reduction mechanism using a plurality of gears in order to decelerate and transmit the output of the motor to the drive wheels. The reduction mechanism reduces the rotation of the motor and transmits the rotation to the crankshaft.

JP 2014-113912 A

  As shown in Patent Document 1, a conventional power-assisted bicycle employs a planetary reduction mechanism using a planetary gear as a reduction gear provided in a drive unit. For this reason, there has been a problem that the configuration of the speed reduction mechanism is complicated.

  Further, since the planetary gear mechanism includes a plurality of planetary gears arranged in parallel along the axial direction of the crankshaft, the drive unit requires a lot of space along the axial direction. Therefore, there is a problem that it is difficult to reduce the size of the drive unit.

  Accordingly, an object of the present invention is to simplify and miniaturize the structure of a drive unit for a battery-assisted bicycle provided with a speed reduction mechanism.

  In order to solve the above-described problems, the present invention includes a crankshaft that is housed in a casing and receives pedaling force, a motor that outputs driving force, a pedaling force transmission mechanism that transmits rotation of the crankshaft, A drive unit for a battery-assisted bicycle, comprising: a combined force output unit that adds the rotation of the pedal force transmission mechanism and the output of the motor to transmit to the driving wheel; and a speed reduction mechanism provided between the motor and the combined force output unit. The speed reduction mechanism includes one raceway on a motor input member that is rotated by the output of the motor, the other raceway facing the one raceway, the one raceway and the other raceway. A plurality of rollers are arranged along the circumferential direction between the races, and the plurality of rollers are held by a carrier, and the rotation of the carrier or the rotation of the other race is accompanied by the rotation of each roller. The motor-assisted bicycle drive unit is a roller reduction gear having a driving force transmission member for guiding the part was adopted.

  In this configuration, the one raceway is an inner raceway, the other raceway is an outer race, and a configuration in which the outer race is integrated with a motor housing that holds the motor may be adopted. it can.

  Further, in each of the configurations, it is possible to adopt a configuration in which the shaft center of the one race ring is provided eccentrically with respect to the rotation center of the motor input member.

  Furthermore, in each structure, the said one track ring can employ | adopt the structure currently formed by the member integral with the said motor input member.

  Moreover, the structure which provided the reverse input prevention mechanism which regulates transmission of the rotation from the said driving wheel side to the said motor side between the said motor and the said resultant force output part is employable.

  At this time, the reverse input prevention mechanism includes an input shaft on the driving force transmission member side and an output shaft on the combined force output unit side, and the driving force transmission member and the input shaft are formed as an integral member. A configuration can be adopted.

  The reverse input prevention mechanism may employ a configuration that is a one-way clutch or a reverse input cutoff clutch in which the input shaft is an inner ring member and the output shaft is an outer ring member.

  The present invention employs a roller speed reducer using a roller as a planetary member instead of a conventional planetary speed reducing mechanism using a planetary gear as a speed reducing mechanism provided in a battery-assisted bicycle drive unit. The thickness can be reduced with respect to the axial direction of the crankshaft, and the degree of freedom of layout of the entire apparatus is improved. That is, the structure of the battery-assisted bicycle drive unit including the speed reduction mechanism can be simplified and downsized.

1 shows a first embodiment of the present invention, in which (a) is a longitudinal sectional view, (b) is a sectional view taken along line BB of (a), and (c) is an enlarged view of a main part of (b). Longitudinal sectional view showing a second embodiment of the present invention 3A and 3B show a third embodiment of the present invention, in which FIG. 3A is a longitudinal sectional view, FIG. 3B is a sectional view taken along line BB in FIG. 3A, and FIGS. FIG. 4 shows a fourth embodiment of the present invention, where (a) is a longitudinal sectional view, and (b) is a sectional view taken along line BB of (a). Overall view of a battery-assisted bicycle

  An embodiment of the present invention will be described with reference to FIGS. In each of the embodiments shown in FIGS. 1 to 4, the driving force generated by the pedal received by the pedal and the driving force output from the motor as auxiliary power are combined, and the combined driving force is transmitted to the driving wheels. The drive unit C used for the battery-assisted bicycle that travels by this, and the battery-assisted bicycle 50 using the drive unit C. FIG. 5 is an overall view of a battery-assisted bicycle corresponding to each embodiment described later.

  In the battery-assisted bicycle 50, a drive unit C having a drive motor is attached to a frame F connecting the front wheel 51 and the drive wheel 52 in the vicinity of the center between the front wheel 51 and the rear wheel 52 that is a drive wheel. Center motor system.

  At the time of driving, that is, when a pedaling force is transmitted to the crankshaft 2 through the pedal 53 or when a driving force by the output of the motor 3 is inputted, the crank sprocket 6 of the driving unit C and the rear wheel 52 are provided. A driving force can be transmitted to the rear wheel 52 via a power transmission element 7 such as an endless chain connecting the rear sprocket 54 as input means.

  Note that the battery-assisted bicycle and the electric motorcycle are set so that the assisting ratio of the driving force by the driving motor with respect to the driving force by human power is different, and the main structure of the driving force transmission mechanism is the same. Therefore, in the following embodiments, the configuration of the present invention that can be applied to both the battery-assisted bicycle and the electric motorcycle will be described by collectively referring to the battery-assisted bicycle and the electric motorcycle as the battery-assisted bicycle.

(First embodiment)
As shown in FIG. 1, the configuration of the drive unit of the first embodiment is housed in a casing 1, a crankshaft 2 to which a pedaling force is input, a motor 3 that outputs a driving force, and rotation of the crankshaft 2. Is transmitted between the motor 3 and the resultant force output unit 5, and the reduction force mechanism provided between the motor 3 and the resultant force output unit 5. 20 is provided.

  The crankshaft 2 rotated by the pedal force applied to the pedal 53 by the driver is perpendicular to the frame F extending in the front-rear direction connecting the front wheels 51 and the rear wheels 52, that is, in the left-right direction as viewed from the driver. Has been placed. The crankshaft 2 is supported by the frame F so as to be rotatable around the shaft by a bearing (not shown in FIG. 1) provided at the end thereof.

  The rotation of the crankshaft 2 due to the pedaling force is transmitted to the resultant force output unit 5 by the pedaling force transmission mechanism 40. The rotation of the resultant force output unit 5 is transmitted to the drive wheel 52 through the sprocket 6 and the power transmission element 7.

  The pedal force transmission mechanism 40 includes a cylindrical sun gear 41 attached to the outer periphery of the crankshaft 2, a first gear 42 that meshes with the sun gear 41, a second gear 43 that meshes with the first gear 42, and a second gear 43. A third gear 45 that is coupled through the coupling shaft 44 and rotates integrally with the second gear 43, and an output side gear 46 that meshes with the third gear 45 and is connected to the resultant force output unit 5.

  The sun gear 41 rotates around the axis integrally with the crankshaft 2. The first gear 42 has an annular shape with teeth formed on the inner diameter side and the outer diameter side, and rotates around the axis of the crankshaft 2 as the sun gear 41 rotates. The second gear 43 and the third gear 45 rotate around the axis of the connecting shaft 44 held by the casing 1. The connecting shaft 44 is fixed to the casing 1 so as to be relatively rotatable, and the second gear 43 and the third gear 45 are connected to the connecting shaft 44.

  In order to assist the pedaling force by human power, the motor 3 that outputs an electric driving force has a cylindrical shape having an insertion hole for the crankshaft 2 at the center thereof, and is coaxial with the rotating shaft of the crankshaft 2. Has been placed. The crankshaft 2 is rotatably supported by a motor case (motor housing) 3d that holds the motor 3.

  The motor 3 includes a cylindrical stator 3b. An exciting coil is wound around the stator 3 b, and the stator 3 b is disposed concentrically with the axis of the crankshaft 2. The stator 3b is fixed to the motor case 3d.

  A cylindrical rotor 3a is rotatably supported on the motor case 3d. The rotor 3a includes a magnet having a plurality of magnetic poles along the circumferential direction of the cylinder. Here, an outer rotor type motor in which the rotor 3a is provided on the outer periphery of the stator 3b is adopted, but other types of motors such as an inner rotor type in which the rotor 3a is provided on the inner periphery of the stator 3b are employed. It may be. The driving of the motor 3 is controlled through an inverter according to the pedaling force, the speed of the bicycle, and the like.

  As shown in FIG. 1, the speed reduction mechanism 20 of this embodiment has an inner ring 12 that is one of the track rings at the axial end of the motor input member 11 that rotates integrally with the rotor 3 a that rotates according to the output of the motor 3. I have. Further, an outer ring 13 which is the other race ring is provided so as to face the inner ring 12.

  Here, one raceway provided on the motor input member 11 is an inner ring 12 and the other raceway facing the outer race 13 is an outer ring 13. The other raceway is reversed inside and outside and one raceway provided on the motor input member 11. The ring may be the outer ring 13 and the other raceway ring facing it may be the inner ring 12.

  Between the inner ring | wheel 12 and the outer ring | wheel 13, the some roller (roller) 21 is arrange | positioned along the circumferential direction as a planetary member. These rollers 21 are held by an annular cage 22 having a plurality of pocket portions 22a along the circumferential direction, and the cage 22 functions as a carrier of the planetary speed reduction mechanism. The planetary member is held in an equal orientation by the carrier.

  One end of the cage 22 in the axial direction (the end on the side close to the resultant force output portion 5) is extended outward in the axial direction, and the end of the extension side receives the resultant rotation of the cage 22 as the rollers 21 revolve. A driving force transmission member 31 that leads to the output unit 5 is provided.

  In this embodiment, the driving force transmission member 31 is configured as an extension of the cage 22. From the cylindrical annular part 22b provided with the pocket part 22a, it extends in one of the axial directions, and then passes through the radial part 22c extending inward in the radial direction of the speed reduction mechanism 20, and further on the part close to the crankshaft 2 A portion extending in a cylindrical shape is a driving force transmission member 31.

  The rotation of the motor 3 from the motor input member 11 is transmitted to the inner ring 12. The outer ring 13 is fixed to a motor case 3d holding a motor. In this embodiment, the outer ring 13 and the motor case 3d are separate members, and the outer ring 13 having the same cylindrical shape is fitted, bonded, welded, etc. to one end in the axial direction of the cylindrical motor case 3d. These are joined by various means.

  As described above, the speed reduction mechanism 20 uses the plurality of rollers 21 between the inner ring 12 and the outer ring 13 as planetary members, and extends the cage 22 that holds the rollers 21 in one of the axial directions so that the resultant force output unit 5 A roller speed reducer is configured as a driving force transmission member 31 leading to.

  A rolling bearing 24 is disposed between the roller 21 that is a planetary member and the inner ring 12 that is the input side. The rolling bearing 24 includes a plurality of balls as rolling elements 24c between the raceway surfaces of the inner member 24a and the outer member 24b arranged concentrically. The roller 21, which is a planetary member of the speed reduction mechanism 20, rolls while contacting the outer diameter surface of the outer member 24 b of the rolling bearing 24. That is, the roller 21 that is a planetary member is a roller speed reducer that is in indirect contact with the inner ring 12 via the rolling bearing 24.

  The inner ring 12 is formed by press-fitting an input shaft 25, which is a separate member, on the outer diameter surface of the motor input member 11, which is a cylindrical member. The motor input member 11 and the input shaft 25 rotate around the axis integrally. The input shaft 25 is press-fitted into the inner diameter surface of the inner member 24 a of the rolling bearing 24. The input shaft 25 and the inner member 24a of the rolling bearing 24 rotate integrally around the axis.

  The rotation center b (referred to as the track surface center b) of the raceway surface 12a of the inner ring 12 provided at the axial end of the motor input member 11 is relative to the rotation center a (referred to as the input rotation center a) of the motor input member 11. The distance w is eccentric. The raceway surface center b of the raceway surface 12a coincides with the center of the outer diameter surface of the outer member 24b, and the input rotation center a of the motor input member 11 coincides with the axis of the crankshaft 2. For this reason, the center of the outer diameter surface of the outer member 24b (corresponding to the track surface center b) is eccentric by a distance w with respect to the axis of the crankshaft 2 (corresponding to the input rotation center a). .

  Due to the eccentricity of the input shaft 25, the input shaft 25 rotates once around the axis, so that the outer member 24 b of the rolling bearing 24 rotates while being eccentric with respect to the input rotation center a.

  As shown in FIG. 1B, the roller 21 positioned on the eccentric side of the inner ring 12, that is, the roller 21 positioned at the position where the radial distance between the outer member 24 b and the outer ring 13 is the smallest is the outer ring 13. Are recessed into a recess 13a between cam ridges 13b provided at equal intervals along the inner diameter surface. On the other hand, the roller 21 on the opposite side to the eccentric side, that is, the roller 21 positioned at the place where the radial distance between the outer member 24b and the outer ring 13 is the largest is the recess 13a between the cam crests 13b of the outer ring 13. You are leaving.

  In this embodiment, the interval in the circumferential direction of the rollers 21 (the angle between the arrangement directions of the adjacent rollers 21) is set to be different from the interval (same as above) of the recesses 13a, and the intervals (same as above) are mutually different. The relationship is not a divisor relationship (a disjoint relationship).

  The roller 21 on the eccentric side enters the recess 13a on the inner diameter surface of the outer ring 13, and the roller 21 is pressed in the circumferential direction by friction with the outer member 24b as the outer member 24b of the rolling bearing 24 rotates. Is done. For this reason, the roller 21 on the eccentric side in the recess 13 a revolves around the axis of the rolling bearing 24 while rotating around the axis of the roller 21, and one cam peak 13 b along the inner diameter surface of the outer ring 13. Overcoming the minute, it moves to the adjacent recess 13a. Since the rollers 21 are held in an equally divided direction along the circumferential direction by the cage 22, the cage 22 rotates and the rotation is output. The movement amount (rotation angle) of the cage 22 is decelerated compared to the movement amount (rotation angle) of the outer member 24b and the movement amount (rotation angle) of the inner member 24a. Deceleration to the output side.

  In the present invention, as described above, a roller speed reducer is used instead of the conventional planetary speed reducing mechanism as the speed reducing mechanism provided in the battery-assisted bicycle drive unit, so that the same reduction ratio with respect to the axial direction of the crankshaft. Thinning is possible, and the degree of freedom of layout of the entire apparatus is improved. That is, the structure of the drive unit for the battery-assisted bicycle provided with the speed reduction mechanism can be simplified and miniaturized. That is, it is possible to significantly reduce the axial length as compared with the case where a roller speed reducer is arranged coaxially with the motor and a conventional planetary speed reducing mechanism is used.

  A one-way clutch 36 is provided as a reverse rotation preventing means 35 between the resultant force output unit 5 and the driving force transmission member 31.

  The one-way clutch 36 includes a clutch inner member 36a as an input member on the driving force transmission member 31 side, and a clutch outer member 36b as an output member on the resultant force output portion 5 side. The clutch inner member 36 a is provided as an integral member or a separate member joined to the driving force transmission member 31, and rotates integrally with the driving force transmission member 31. The clutch outer member 36 b is provided as an integral member or a separate member joined to the resultant force output portion 5, and rotates integrally with the resultant force output portion 5.

  An engagement member such as a roller or a sprag is provided between the clutch inner member 36a and the clutch outer member 36b, and the engagement member is engaged with a cam surface provided on the clutch inner member 36a or the clutch outer member 36b. Thus, the relative rotation of the clutch inner member 36a and the clutch outer member 36b in one direction around the axis is restricted, and the engagement between the clutch inner member 36a and the clutch outer member 36b is released. Allow relative rotation around the axis in other directions. A ratchet type one-way clutch provided with a ratchet pawl between the clutch inner member 36a and the clutch outer member 36b may also be used.

  The one-way clutch 36 may be reversed inward and outward, and the clutch outer member 36b may be disposed as the input member on the driving force transmission member 31 side, and the clutch inner member 36a may be disposed as the output member on the resultant force output unit 5 side.

  The reverse rotation preventing means 35 transmits the driving force when traveling forward and when the rotation of the resultant force output unit 5 is faster than the rotation of the driving force transmission member 31, that is, when the rotation by the stepping force is faster than the rotation by the motor 3. The relative rotation between the member 31 and the resultant force output unit 5 is allowed. Further, when the forward movement is performed and the rotation of the resultant force output unit 5 is slower than the rotation of the driving force transmission member 31, the driving force transmission member 31 and the resultant force output unit 5 are coupled. When the driving force transmission member 31 and the resultant force output unit 5 are coupled, thereafter, the driving force of the motor 3 is transmitted to the resultant force output unit 5. Further, by providing the reverse rotation preventing means 35, it is possible to prevent a situation in which it becomes heavy to push the bicycle due to the motor 3 rotating when the bicycle is moved backward, that is, when the bicycle is pushed backward by hand. it can.

  When the driving force from the motor 3 is transmitted to the resultant force output unit 5, the rotation of the resultant force output unit 5 is transmitted in the reverse direction to the crankshaft 2 and the pedal through the pedaling force transmission mechanism 40. The driving force by the motor 3 is output so as to complement the difference between the pedaling force torque detected by a sensor or the like provided around the sun gear 41 and the rotation of the driving wheel 52, that is, the rotation of the resultant force output unit 5. The pedal 53 does not rotate at a high speed against the driver's will (more than the rotation speed by human power).

(Second embodiment)
Since the basic configuration of the second embodiment is the same as that of the first embodiment, the difference will be mainly described (the same applies to each embodiment described later). The configuration of the drive unit C (see FIG. 5) of the second embodiment is such that the outer ring 13 of the speed reduction mechanism 20 and the motor case 3d are formed as an integral member, as shown in FIG. Further, the input shaft 25 of the speed reduction mechanism 20 and the motor input member 11 are formed as an integral member. By adopting such a configuration, the number of parts is reduced, the assembly is facilitated, and the cost is reduced.

(Third embodiment)
As shown in FIG. 3, the configuration of the drive unit C of the third embodiment is provided with a reverse input blocking clutch 37 as the reverse rotation preventing means 35 instead of the wineway clutch 36. In this embodiment, a free type torque diode (registered trademark) is employed as the reverse input cutoff clutch 37. The free type torque diode is a torque diode of a type in which the rotational torque from the input shaft is transmitted to the output shaft, but the rotational torque from the output shaft is not transmitted to the input shaft due to idling of the output shaft.

  The configuration of the reverse input cutoff clutch 37 includes a clutch outer member 37b as an input member on the driving force transmission member 31 side, and a clutch inner member 37a as an output member on the resultant force output portion 5 side.

  The clutch outer member 37 b is provided as an integral member or a separate member joined to the driving force transmission member 31, and rotates integrally with the driving force transmission member 31. The clutch inner member 37 a is provided as an integral member or a separate member joined to the resultant force output portion 5, and rotates integrally with the resultant force output portion 5.

  A cam surface 38 is formed on the inner peripheral surface of the clutch outer member 37b. The cam surface 38 has inclined surfaces 38b and 38c that gradually become shallower on both sides along the circumferential direction from a bottom portion 38a formed deepest on the outer diameter side. The outer peripheral surface of the clutch inner member 37a is a cylindrical surface. A plurality of engagement elements 37c are disposed between the inner peripheral surface of the clutch outer member 37b and the outer peripheral surface of the clutch inner member 37a. Here, a roller is used as the engagement element 37c, but this may be a ball.

  The engagement element 37c is held by a retainer 37d along the circumferential direction, and the engagement element 37c is cam-surfaced by an elastic member 39 for centering provided between the retainer 37d and the clutch outer member 37b. 38 is maintained at the position of the bottom 38a.

  When the driving force from the motor 3 is not transmitted to the clutch outer member 37b on the input side, the engaging element 37c is in a neutral state located at the bottom 38a of the cam surface 38 by the elastic force of the elastic member 39, and the clutch The outer member 37b and the clutch inner member 37a are in a relatively rotatable state.

  When the clutch outer member 37b on the input side is rotated in one direction (forward direction) as shown by an arrow a in FIG. 3 (d) by the driving force from the motor 3, the retainer 37d is accordingly elastic member 39. The engaging element 37c that rotates against the elastic force of the moving member and that is held by the holder 37d moves along the inclined surface 38c of the cam surface 38. Eventually, the engagement element 37c enters the narrow space of the wedge at the end of the cam surface 38, and connects the clutch outer member 37b and the clutch inner member 37a. When the clutch outer member 37b and the clutch inner member 37a are locked, the driving force is transmitted from the driving force transmitting member 31 side to the resultant force output unit 5 side. When the input of the driving force to the clutch outer member 37b is stopped, the engagement member 37c quickly shifts to the neutral state shown in FIG. 3C by the elastic force of the elastic member 39, and the clutch outer member 37b and the clutch inner member are inward. The connection with the member 37a is released.

  As a case where the torque is input from the resultant force output unit 5 side which is the output shaft, for example, a case where the bicycle travels forward with inertia like when the bicycle goes down a slope is assumed. In this case, even if the clutch inner member 37a on the output side rotates in one direction (forward direction) as indicated by an arrow b in FIG. 3C, the engagement element 37c is held in a neutral state by the elastic member 39. Therefore, the clutch inner member 37a and the clutch outer member 37b are not coupled, and torque from the output side is not transmitted to the input side. Even if the engaging element 37c is engaged with the narrow space of the wedge by forward traveling at the preceding stage, the clutch inner member 37a on the output side is in one direction (forward direction) with respect to the clutch outer member 37b. ), The clutch outer member 37b stops rotating, so that its engagement is released by the elastic force of the elastic member 39, and the engagement member 37c can quickly shift to the neutral state.

  Similarly, as a case where torque is input from the resultant force output unit 5 side, which is an output shaft, for example, a reverse time in which the bicycle is pushed back by hand is assumed. In this case, even if the clutch inner member 37a on the output side rotates in the other direction (reverse direction) which is the opposite direction of the arrow b in FIG. 3C, the engaging member 37c is brought into the neutral state by the elastic member 39. Since the clutch inner member 37a and the clutch outer member 37b are not coupled with each other, the torque from the output side is not transmitted to the input side. Even if the engaging element 37c is engaged with the narrow space of the wedge by forward traveling at the preceding stage, the clutch inner member 37a on the output side is in the other direction (reverse direction) with respect to the clutch outer member 37b. ), The clutch outer member 37b stops rotating, so that its engagement is released by the elastic force of the elastic member 39, which is a switch spring, and the engagement element 37c can quickly shift to the neutral state. .

(Fourth embodiment)
As shown in FIG. 4, the configuration of the drive unit C of the fourth embodiment is a clutch as an input member on the drive force transmission member 31 side by reversing the configuration of the reverse input cutoff clutch 37 in the third embodiment. The inner member 37a includes a clutch outer member 37b as an output member on the resultant force output unit 5 side.

  In this embodiment, the output side member of the reverse input cutoff clutch 37 is formed as a member integrated with the resultant force output portion 5. That is, since the output member on the resultant force output portion 5 side is the clutch outer member 37 b, the clutch outer member 37 b can be formed as a member integrated with the resultant force output portion 5. This reduces the number of parts, facilitates assembly, and reduces costs.

  As in the third embodiment described above, the clutch outer member 37b is provided as an input member on the driving force transmission member 31 side, and the clutch inner member 37a is provided as an output member on the resultant force output portion 5 side. In this case, the clutch inner member 37 a that is the output side member of the reverse input cutoff clutch 37 can be formed as a member integrated with the resultant force output unit 5.

(Other)
In each of the embodiments described above, the one-way clutch 36, the reverse input cutoff clutch 37, and the like can be selectively employed as the reverse input prevention means 35.

  Further, as the speed reduction mechanism 20, in each of the above-described embodiments, planetary members such as a plurality of rollers are arranged along the circumferential direction between one raceway ring and the other raceway ring, and the plurality of planetary members are used as carriers. The mechanism including the driving force transmission member 31 that guides the rotation of the carrier accompanying the revolution of each planetary member due to the torque input to one of the races to the resultant force output unit 5 is employed. Alternatively, a mechanism including a driving force transmission member 31 that guides the rotation of the other raceway to the resultant force output unit 5 may be employed.

  Further, as the speed reduction mechanism 20, a roller speed reducer having another form may be adopted. For example, a plurality of rollers (rollers) supported by a carrier are held in an annular space between an outer ring and an inner ring arranged concentrically, and high-speed rotation input to one of the outer ring or the inner ring A roller speed reducer that outputs as a reduced speed rotation from the carrier or the other of the outer ring or the inner ring through the friction transmission of the member can be mentioned. That is, this is a roller speed reducer in which a plurality of rollers are arranged in an annular space between the cylindrical surface of the inner ring outer periphery and the cylindrical surface of the outer ring inner periphery arranged concentrically. The rotation of one of the race rings on the input side causes the roller shaft to revolve while rotating directly between the outer ring and the inner ring while directly or indirectly contacting the outer ring and the inner ring. Or the rotation of the other race ring rotated by frictional transmission via a roller is output to the output shaft.

  Here, the roller is supported rotatably (self-rotating) by the carrier. For example, a roller (roller) of a roller speed reducer can be supported on a carrier pin by a rolling bearing such as a needle roller bearing. In addition, one of the race rings on the input side is supported by a fixed housing or the like via a rolling bearing. For example, one of the races can be supported rotatably on a motor case holding the motor 3 via a rolling bearing.

DESCRIPTION OF SYMBOLS 1 Casing 2 Crankshaft 3 Motor 5 Combined force output part 6 Crank sprocket 7 Power transmission element 11 Motor input member 12 Inner race ring (inner ring)
13 Outer race (outer ring)
20 Deceleration mechanism 21 Planetary member (roller)
22 Carrier (Retainer)
24 Rolling bearing 25 Input shaft 31 Driving force transmission member 35 Reverse rotation preventing means 36 One-way clutch 36a Clutch inner member 36b Clutch outer member 37 Reverse input blocking clutch 37a Clutch inner member 37b Clutch outer member

Claims (7)

The crankshaft housed in the casing, to which the pedaling force is input, the motor that outputs the driving force, the pedaling force transmission mechanism that transmits the rotation of the crankshaft, the rotation of the pedaling force transmission mechanism and the output of the motor are added together. In a drive unit for a battery-assisted bicycle, comprising: a resultant force output unit that transmits to the driving wheel; and a speed reduction mechanism provided between the motor and the resultant force output unit
The speed reduction mechanism includes one raceway on a motor input member that rotates according to the output of the motor, the other raceway facing the one raceway, and the one raceway and the other raceway. A plurality of rollers are arranged along the circumferential direction between the rollers, and the plurality of rollers are held by a carrier, and the rotation of the carrier or the rotation of the other raceway associated with the revolution of each roller is guided to the resultant force output unit. A drive unit for a battery-assisted bicycle, which is a roller speed reducer provided with a drive force transmission member.   2. The battery-assisted bicycle according to claim 1, wherein the one raceway is an inner raceway, the other raceway is an outer race, and the outer race is integrated with a motor housing that holds the motor. Drive unit.   The drive unit for a battery-assisted bicycle according to claim 1 or 2, wherein an axis of the one track ring is provided eccentrically with respect to a rotation center of the motor input member.   4. The battery-assisted bicycle drive unit according to claim 1, wherein the one track ring is formed of a member integrated with the motor input member. 5.   5. The electric assistance according to claim 1, wherein a reverse input prevention mechanism is provided between the motor and the resultant force output unit to restrict transmission of rotation from the driving wheel side to the motor side. Bicycle drive unit.   The reverse input prevention mechanism includes an input shaft on the driving force transmission member side and an output shaft on the combined force output unit side, and the driving force transmission member and the input shaft are formed as an integral member. 5. A drive unit for a battery-assisted bicycle according to 5.   The drive unit for a battery-assisted bicycle according to claim 5 or 6, wherein the reverse input prevention mechanism is a one-way clutch or a reverse input cutoff clutch in which the input shaft is an inner ring member and the output shaft is an outer ring member.

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