JP2018102044A - Bicycle generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bicycle generator capable of efficiently generating electric power.SOLUTION: A bicycle generator 10 includes a first member 1, a second member 2, a third member 3, and a coil member 4. The first member 1 and the third member 3 are rotatable around a central axis. The first magnetic pole group of the first member 1 includes a plurality of magnetic poles arranged so as to alternately have different polarities in the circumferential direction. The second magnetic pole group of the second member 2 includes a plurality of magnetic poles arranged so as to alternately have different polarities in the circumferential direction. Magnetic members 31 of the third member 3 are arranged with a space in the circumferential direction. The third member 3 is disposed between the first member 1 and the second member 2 in the radial direction. Each magnetic member 31 has a plurality of magnetic material pieces laminated in the circumferential direction.SELECTED DRAWING: Figure 8

Description

  The present invention relates to a bicycle generator.

  Various bicycle generators that generate electric power for driving electrical components such as headlamps have been proposed (see Patent Document 1). This bicycle generator generates electric power by utilizing rotation of a rotating part of a bicycle, for example, rotation of a wheel.

Japanese Patent Laid-Open No. 2015-130782

  In the bicycle generator as described above, when the third member is deformed, the third member may interfere with the second member when the third member rotates relative to the second member.

  Then, the subject of this invention is providing the generator for bicycles which can suppress a deformation | transformation of a 3rd member.

  The bicycle generator according to the first aspect of the present invention is configured to generate electricity based on rotation by a rotating portion of the bicycle. The bicycle generator includes a first member, a second member, a third member, and a coil member. The first member is rotatable around the central axis. The first member has a first magnetic pole group. The first magnetic pole group includes a plurality of magnetic poles arranged so as to have different polarities alternately in the circumferential direction. The second member has a second magnetic pole group. The second magnetic pole group includes a plurality of magnetic poles arranged so as to have different polarities alternately in the circumferential direction. The third member has a plurality of magnetic bodies arranged at intervals in the circumferential direction. The third member is disposed between the first member and the second member in the radial direction. The coil member is configured such that an induced current flows by the rotation of the first member. The second member and the third member are configured to rotate relatively around the central axis by the rotation of the rotating portion. Each magnetic body has a plurality of magnetic body pieces stacked in the circumferential direction.

  According to this configuration, each magnetic body of the third member has a plurality of magnetic body pieces. And each magnetic body piece is laminated | stacked on the circumferential direction. For this reason, the deformation strength in the radial direction of the third member is improved. As a result, even when a centrifugal force acts on the third member, the third member can be prevented from being deformed in the radial direction.

  Preferably, each magnetic piece has a radial dimension larger than a circumferential dimension. According to this configuration, the strength against the radial deformation of the third member can be further improved.

  Preferably, each magnetic body further includes an insulating film disposed between each magnetic piece. According to this structure, the eddy current loss in each magnetic body can be reduced.

  Preferably, each magnetic body has a radial dimension larger than a circumferential dimension. According to this configuration, the strength against the radial deformation of the third member can be further improved.

  Preferably, the number of magnetic poles of the second magnetic pole group is larger than the number of magnetic poles of the first magnetic pole group. According to this configuration, the first member can rotate faster than the rotating part of the bicycle. As a result, the bicycle generator can efficiently generate electric power.

  Preferably, the axial length of each magnetic body is longer than the axial length of the first magnetic pole group. According to this configuration, leakage current can be reduced.

  Preferably, the axial length of each magnetic body is longer than the axial length of the second magnetic pole group. According to this configuration, leakage current can be reduced.

  Preferably, the bicycle generator further includes a support member. This support member can be rotated around the central axis by the rotating portion, and supports each magnetic piece. According to this configuration, the third member can be further prevented from being deformed in the radial direction by being supported by the support member.

  Preferably, the support member has a plurality of insertion holes. Each magnetic piece is inserted into the insertion hole. According to this configuration, by inserting each magnetic piece into the insertion hole, it is possible to maintain a state in which each magnetic piece is stacked in the circumferential direction.

  Preferably, each magnetic body is inserted into each insertion hole. According to this configuration, by inserting each magnetic body into the insertion hole, it is possible to maintain a state where the magnetic body pieces are stacked in the circumferential direction.

  Preferably, the support member includes a first support member and a second support member. The first and second support members are arranged at an interval in the axial direction and support both ends of each magnetic piece. According to this ward administration, since both ends of the third member are supported by the first and second support members, the strength against the radial deformation of the third member can be improved.

  Preferably, the first and second support members have respective insertion holes. According to this configuration, the third member can be supported by inserting both end portions of the third member into the respective insertion holes of the first and second support members.

  Preferably, the support member further includes a connecting member that connects the first support member and the second support member. According to this configuration, it is possible to reduce torsional torque acting on the third member.

  Preferably, the support member is made of a nonmagnetic material or a nonconductive material. According to this configuration, power can be generated efficiently.

  Preferably, the bicycle generator further includes a first bearing member. The first bearing member is disposed between the first member and the support member, and supports the first member rotatably with respect to the support member. According to this structure, since the 1st member can be rotated smoothly, electric power can be produced | generated efficiently.

  Preferably, the bicycle generator further includes a hub shaft and a second bearing member. The second bearing member is disposed between the hub shaft and the support member, and supports the support member rotatably with respect to the hub shaft. According to this structure, since a support member can be rotated smoothly, electric power can be produced | generated efficiently.

  Preferably, the second bearing member is disposed on the radially inner side of the first bearing member. According to this configuration, the bicycle generator can be reduced in size in the axial direction.

  Preferably, each magnetic body is disposed between the first magnetic pole group and the second magnetic pole group in the radial direction. According to this configuration, power can be generated efficiently.

Preferably, the number of magnetic material, the number of magnetic poles in the first magnetic pole group and _{N 1,} when the number of magnetic poles of the second pole group was _{N 2,} expressed in _{N 3 = N 2/2 ±} N 1/2 that is an integer _{N 3.} According to this configuration, the first member can rotate at a faster rotational speed than the third member, and therefore can efficiently generate electric power.

  Preferably, one of the second member and the third member is rotatable around the central axis by the rotation of the rotating portion. The other of the second member and the third member is not rotatable around the central axis. According to this configuration, power can be generated efficiently.

  The bicycle generator according to the second aspect of the present invention is configured to generate electricity based on rotation by a rotating portion of the bicycle. The bicycle generator includes a first member, a second member, a third member, and a coil member. The first member is rotatable around the central axis. The first member has a first magnetic pole group. The first magnetic pole group includes a plurality of magnetic poles arranged so as to have different polarities alternately in the circumferential direction. The second member has a second magnetic pole group. The second member includes a plurality of magnetic poles arranged so as to have different polarities alternately in the circumferential direction. The third member has a plurality of magnetic bodies arranged in the circumferential direction. The third member is disposed between the first member and the second member in the radial direction. The coil member is configured such that an induced current flows by the rotation of the first member. The second member and the third member are configured to rotate relatively around the central axis by the rotation of the rotating portion. Each magnetic body has a radial dimension larger than a circumferential dimension.

  According to this configuration, each magnetic body has a radial dimension larger than a circumferential dimension. For this reason, even if it is a case where a centrifugal force acts on the 3rd member, the deformation | transformation in the radial direction of a 3rd member can be suppressed.

  Preferably, at least one of the magnetic bodies includes a plurality of magnetic pieces that are stacked in the radial direction. According to this configuration, the radial deformation of the third member can be suppressed.

  The bicycle generator according to the present invention can suppress deformation of the third member.

The side view of the bicycle concerning an embodiment. The front view of the generator for bicycles concerning an embodiment. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. The perspective view of the 2nd member concerning an embodiment. The front view of the yoke piece which concerns on embodiment. The exploded view of FIG. The cross-sectional perspective view of the 1st member, 3rd member, and support member which concern on embodiment. BB sectional drawing of FIG. The perspective view of the magnetic body which concerns on embodiment. The perspective view of the 1st member concerning an embodiment. The schematic of the generator for bicycles concerning a modification. Sectional drawing of the generator for bicycles which concerns on a modification. The cross-sectional perspective view of the support member which concerns on a modification. The perspective view of the magnetic body which concerns on a modification.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a bicycle generator according to the present invention will be described with reference to the drawings. FIG. 1 is a side view of a bicycle 101 to which a bicycle generator 10 is attached. As shown in FIG. 1, the bicycle 101 includes a frame 102, a front wheel 103, a rear wheel 104, and a bicycle generator 10. The bicycle 101 further includes a chain 105 and a crank 107 to which a pedal 106 is attached. The crank 107 includes a crankshaft 107a and a pair of crank arms 107b. Each crank arm 107b is provided at both ends of the crankshaft 107a.

  FIG. 2 is a front view of the bicycle generator 10. As shown in FIG. 2, the bicycle generator 10 is a generator that is attached to a pair of front forks 108 of a bicycle and generates electric power based on rotation by a front wheel 103 (an example of a rotating portion) as a bicycle wheel.

  3 is a cross-sectional view taken along line AA in FIG. As shown in FIG. 3, the bicycle generator 10 includes a first member 1, a second member 2, a third member 3, and a coil member 4. These members are arranged in the order of the coil member 4, the second member 2, the third member 3, and the first member 1 from the radially inner side. The bicycle generator 10 further includes a hub shaft 5 and a support member 6. The central axis 51 of the hub shaft 5 corresponds to the central axis of the present invention. In the following description, the radial direction means the radial direction of a circle with the central axis 51 as the center. Further, the circumferential direction means a circumferential direction of a circle around the central axis 51. The axial direction means a direction in which the central axis 51 extends.

  As shown in FIG. 2, the hub shaft 5 extends between the pair of front forks 108. The hub shaft 5 is hollow (see FIG. 3). The hub shaft 5 is fixed to the front fork 108 by a quick release mechanism (not shown). A connector 111 is attached to a first end portion (left end portion in FIG. 2) of the hub shaft 5. The connector 111 is a member for supplying electric power from the coil member 4 to an electrical component such as the headlamp 110.

  As shown in FIG. 3, the second member 2 is attached to the hub shaft 5 so as not to rotate. That is, the second member 2 cannot rotate around the central axis 51. The second member 2 has a second magnetic pole group including a plurality of magnetic poles. Hereinafter, details of the second member 2 will be described.

  FIG. 4 is a perspective view showing the second member 2 attached to the hub shaft 5. As shown in FIG. 4, the second member 2 includes a yoke portion 22 and a plurality of magnets 23. The yoke portion 22 includes a plurality of claw portions 221 extending in a direction along the central axis 51. Each nail | claw part 221 is arrange | positioned at intervals in the circumferential direction.

  Each magnet 23 is disposed between the claw portions 221. Each magnet 23 extends in a direction along the central axis 51. As for each magnet 23, one magnetic pole is arrange | positioned at radial direction outer side, and the other magnetic pole is arrange | positioned at radial direction inner side. In each magnet 23, the magnetic poles have the same direction.

  For example, each magnet 23 is disposed such that the N pole faces the radially outer side, and the S pole faces the radially inner side. In this case, each claw 221 is magnetized so that the radially outer surface of each claw 221 becomes the south pole. In addition, each magnet 23 may be arrange | positioned so that a south pole may face a radial direction outer side, and a north pole may be arrange | positioned so that it may face a radial direction inner side. In this case, each nail | claw part 221 is magnetized so that the outer surface of the radial direction of each nail | claw part 221 may become N pole. As described above, the second magnetic pole group in the second member 2 includes the plurality of claw portions 221 and the plurality of magnets 23. The magnetic poles of the second magnetic pole group are arranged so as to have different polarities alternately in the circumferential direction. The second magnetic pole group is disposed on the radially outer side than the coil member 4.

  Specifically, the yoke portion 22 has a plurality of yoke pieces 220. FIG. 5 is a front view of one yoke piece 220 attached to the hub shaft 5. As shown in FIG. 5, the yoke piece 220 includes a claw portion 221, a base portion 222, and a connecting portion 223. For example, the yoke piece 220 can be formed of electromagnetic steel or the like.

  The base portion 222 extends along the central axis 51 and is in contact with the hub shaft 5. The claw portion 221 extends along the central axis 51 and is arranged at a distance from the base portion 222 in the radial direction. Each base part 222 is in contact with each base part 222 adjacent in the circumferential direction. The claw portion 221 has substantially the same length as the base portion 222 and is shorter than the base portion 222 in detail. The connecting portion 223 extends in the radial direction, and connects the claw portion 221 and the base portion 222 at an end portion in the axial direction (left end portion in FIG. 5). A plurality of yoke pieces 220 configured in this way are arranged radially around the central axis 51.

  FIG. 6 is an exploded view of FIG. In FIG. 6, the magnet 23 is not shown. The 2nd member 2 mentioned above is demonstrated still in detail, referring FIG. As shown in FIG. 6, the yoke part 22 is comprised from the 1st yoke part 22a and the 2nd yoke part 22b.

  The first yoke portion 22a includes first yoke pieces 220a corresponding to the plurality of yoke pieces 220 described above. Each first yoke piece 220a has a first claw portion 221a, a first base portion 222a, and a first connecting portion 223a. The first claw portion 221a corresponds to the claw portion 221 described above, the first base portion 222a corresponds to the base portion 222 described above, and the first connection portion 223a corresponds to the connection portion 223 described above. Each first claw portion 221a extends in the first direction (the right direction in FIG. 6) along the central axis 51. Each first base portion 222 a also extends in the first direction along the central axis 51.

  The second yoke portion 22b has second yoke pieces 220b corresponding to the plurality of yoke pieces 220 described above. Each second yoke piece 220b has a second claw portion 221b, a second base portion 222b, and a second connecting portion 223b. The second claw portion 221b corresponds to the claw portion 221 described above, the second base portion 222b corresponds to the base portion 222 described above, and the second connection portion 223b corresponds to the connection portion 223 described above. The second yoke piece 220b is opposite in the axial direction to the first yoke piece 220a described above. That is, each second claw portion 221b extends in the second direction (left direction in FIG. 6) opposite to the first direction along the central axis 51. Each second base portion 222 b also extends in the second direction along the central axis 51. And the 2nd connection part 223b is extended in radial direction, and connects the 2nd nail | claw part 221b and the 2nd base part 222b by the edge part (right end part of FIG. 6) of an axial direction.

The first yoke portion 22a and the second yoke portion 22b are arranged so that the first claw portions 221a and the second claw portions 221b are alternately arranged in the circumferential direction. Each magnet 23 is arrange | positioned in the circumferential direction between each 1st nail | claw part 221a and each 2nd nail | claw part 221b. The second magnetic pole group includes a plurality of first claw portions 221 a, a plurality of second claw portions 221 b, and a plurality of magnets 23. Further, the number N ₂ of magnetic poles in the second magnetic pole group is larger than the number N ₁ of magnetic poles in the first magnetic pole group described later. That is, the total number N ₂ of the plurality of first claw portions 221a, the plurality of second claw portions 221b, and the plurality of magnets 23 is larger than the number of magnetic poles N ₁ of the first magnetic pole group described later.

  As shown in FIG. 6, the coil member 4 is wound around the central axis 51. Specifically, the coil member 4 is wound around the central axis 51 so as to extend between the claw portions 221 and the base portion 222 of the yoke portion 22. That is, in the second member 2, the claw portions 221 and the magnets 23 are disposed on the radially outer side of the coil member 4, but the base portions 222 are disposed on the radially inner side of the coil member 4. That is, the coil member 4 is wound around each base portion 222. The coil member 4 is configured such that an induced current flows by the rotation of the first member 1. The coil member 4 has a cylindrical shape as a whole.

  FIG. 7 is a cross-sectional perspective view showing details of the first member 1, the third member 3, and the support member 6. As shown in FIG. 7, the third member 3 has a plurality of magnetic bodies 31. The magnetic bodies 31 are arranged at intervals in the circumferential direction. The third member 3 is disposed between the first member 1 and the second member 2 in the radial direction. Specifically, each magnetic body 31 is disposed between the first magnetic pole group and the second magnetic pole group in the radial direction. Moreover, each magnetic body 31 is arrange | positioned radially outside rather than the 2nd magnetic pole group. The third member 3 can be rotated around the central axis 51 by the rotation of the front wheel 103.

  As shown in FIG.8 and FIG.9, as for each magnetic body 31, the dimension of radial direction is larger than the dimension of the circumferential direction. That is, in the cross section perpendicular to the axial direction, the radial dimension of each magnetic body 31 is larger than the circumferential dimension of each magnetic body 31.

  As shown in FIG. 9, each magnetic body 31 has a plurality of magnetic body pieces 311. The plurality of magnetic pieces 311 constituting each magnetic body 31 are stacked in the circumferential direction. For example, in the present embodiment, the magnetic body 31 is configured by laminating three magnetic pieces 311 in the circumferential direction. Each magnetic piece 311 is formed in a plate shape. For example, each magnetic piece 311 can be formed of an electromagnetic steel plate. Each magnetic piece 311 has a radial dimension larger than a circumferential dimension. That is, in the cross section orthogonal to the axial direction, each magnetic piece 311 has a radial dimension larger than a circumferential dimension. Specifically, it arrange | positions so that each main surface of each magnetic piece 311 may face the circumferential direction. Each magnetic piece 311 may be bonded to each other or may not be bonded. When each magnetic body piece 311 is not mutually adhere | attached, the state which comprised the one magnetic body 31 with the some magnetic body piece 311 is maintained by being supported by the support member 6 mentioned later.

  As shown in FIG. 3, each magnetic body 31 extends in the axial direction. Similarly, each magnetic piece 311 extends in the axial direction. The axial length (length in the axial direction) of each magnetic body 31 is longer than the axial length of the first magnetic pole group. The axial length of each magnetic body 31 is longer than the axial length of the second magnetic pole group.

  As shown in FIG. 7, the support member 6 is a member that supports each magnetic body 31. Specifically, the plurality of magnetic pieces 311 are supported. The support member 6 can rotate around the central axis 51 by the rotation of the front wheel 103 of the bicycle. The support member 6 is made of a nonmagnetic material or a nonconductive material. For example, the support member 6 can be formed of stainless steel or the like. However, the support member 6 may be made of resin or ceramics as long as it has sufficient strength while being supported by the front wheel 103 of the bicycle. The support member 6 includes a first support member 6a and a second support member 6b. The first support member 6a and the second support member 6b are disposed at a distance from each other in the axial direction. Both ends of each magnetic body 31 are supported by the first support member 6a and the second support member 6b.

  The first support member 6a has a first cylindrical portion 61a and a first flange portion 62a. The first cylindrical portion 61a is formed in a cylindrical shape. A plurality of first insertion holes 611a (an example of insertion holes) are formed on the first end surface (the right end surface in FIG. 7) of the first cylindrical portion 61a. Each first insertion hole 611a does not penetrate, but may penetrate. The first insertion holes 611a are formed at intervals in the circumferential direction. The first end (the left end in FIG. 7) of each magnetic body 31 is inserted into each first insertion hole 611a. Specifically, the first end of each magnetic body 31 is fitted in each first insertion hole 611a. As described above, the magnetic bodies 31 are inserted into the first insertion holes 611a, so that the state in which the plurality of magnetic body pieces 311 are stacked in the circumferential direction is maintained.

  The first flange portion 62a extends radially outward from the second end portion (left end portion in FIG. 7) of the first cylindrical portion 61a. The first flange portion 62a is formed integrally with the first cylindrical portion 61a. The first flange portion 62a has a plurality of first spoke holes 621a. The first spoke holes 621a are formed at intervals in the circumferential direction. Each spoke 109 of the front wheel 103 is connected to each first spoke hole 621a.

  The second support member 6b has a second cylindrical portion 61b and a second flange portion 62b. The second cylindrical portion 61b is formed in a cylindrical shape, and a plurality of second insertion holes 611b (an example of insertion holes) are formed on the first end face (left end face in FIG. 7). Although this 2nd insertion hole 611b is formed as a through-hole, it does not need to penetrate. The respective second insertion holes 611b are formed at intervals from each other in the circumferential direction. The second end (the right end in FIG. 7) of each magnetic body 31 is inserted into each second insertion hole 611b. Specifically, the second end of each magnetic body 31 is fitted in each second insertion hole 611b. Each magnetic body 31 is supported by the first support member 6a and the second support member 6b in a state of being spaced apart from each other in the circumferential direction. Thereby, a rectangular opening penetrating the third member 3 in the radial direction is formed between the magnetic bodies 31.

  The 2nd flange part 62b is formed in disk shape, and the opening part 622 is formed in the center part. The second cylindrical portion 61b is fitted in the opening 622 of the second flange portion 62b. Thereby, the 2nd flange part 62b and the 2nd cylindrical part 61b are integrally formed. The second flange portion 62b has a plurality of second spoke holes 621b. The second spoke holes 621b are formed at intervals in the circumferential direction. Each spoke 109 of the front wheel 103 is connected to each second spoke hole 621b.

  As shown in FIG. 3, the support member 6 is attached to the hub axle 5 via a pair of second bearing members 7b. Specifically, the first support member 6a is attached to the hub shaft 5 via one second bearing member 7b. A lid member 8 is disposed between the first support member 6a and the first shaft member 7a. Further, a positioning member 9 is disposed between the hub shaft 5 and the first bearing member 7a. The second support member 6b is attached to the hub shaft 5 via the other second bearing member 7b. The second bearing member 7 b allows the third member 3 fitted to the support member 6 to rotate relative to the hub shaft 5 and the second member 2.

  The lid member 8 is fitted in the first support member 6a and rotates integrally with the first support member 6a. The positioning member 9 is a member for preventing the second member 2 from moving in the axial direction. Specifically, the positioning member 9 is fixed to the hub shaft 5, and the end surface is in contact with the first end surface (the left end surface in FIG. 3) of the second member 2. Note that the second end surface (the right end surface in FIG. 3) of the second member 2 is in contact with the shoulder portion 52 of the hub shaft 5. The shoulder 52 restricts the movement of the second member 2 in the axial direction.

  As shown in FIG. 7, the first member 1 is disposed on the radially outer side than the third member 3. The first member 1 is supported by the support member 6 via a pair of first bearing members 7a. Specifically, the first member 1 is supported by the first support member 6a via one first bearing member 7a and supported by the second support member 6b via the other first bearing member 7a. Yes. The first member 1 is rotatably supported by the support member 6 by the first bearing member 7a. That is, the first member 1 can rotate around the central axis 51 with respect to the third member 3. Since the first member 1 is supported by the support member 6 at the outer peripheral portion of the third member 3 to which the power of the front wheel 103 is transmitted, the first member 1 can reinforce the rigidity of the third member 3.

  FIG. 10 is a perspective view of the first member 1. As shown in FIG. 10, the first member 1 has a case portion 11 and a first magnetic pole group. The case part 11 is formed in a cylindrical shape. The first magnetic pole group is attached to the inner peripheral surface of the case portion 11. The first magnetic pole group has a cylindrical shape as a whole. The first magnetic pole group is disposed on the outer side in the radial direction than each magnetic body 31. The first magnetic pole group is composed of a plurality of magnetic poles 12. The magnetic poles 12 are arranged so as to have different polarities alternately in the circumferential direction. Specifically, the first magnetic pole group is composed of one or a plurality of magnets. The magnetic poles 12 of the magnets are arranged so as to have different polarities alternately in the circumferential direction. Each magnetic pole 12 extends in the axial direction. Note that the number of magnetic poles of the first magnetic pole group is the same as the number of the plurality of claw portions 221 included in the yoke portion 22. That is, the number of the magnetic poles 12 is the same as the total number of the first claw portions 221a and the second claw portions 221b.

As shown in FIG. 8, the number of the magnetic body 31 in which the third member 3 has _is an integer _{N 3} represented by _{N 3 = N 2/2 ±} N 1/2. N ₁ represents the number of magnetic poles in the first magnetic pole group, that is, the number of magnetic poles 12. N ₂ represents the number of magnetic poles in the second magnetic pole group, that is, the total number of the first claw portions 221a, the second claw portions 221b, and the magnets 23. That is, in the example shown in FIG. 8, the first magnetic pole group is the number of magnetic poles N ₁ is 28, consisting of 14 pole pairs. The number N ₂ of magnetic poles of the second magnetic pole group is 56. Therefore, N ₃ is set to 42. _{Incidentally, N 3 / (N 1/} 2) is to be greater than 1, _{N 1} and _{N 2} are set.

  In the bicycle generator 10 configured as described above, the first and second support members 6a and 6b connected to the spokes 109 of the front wheel 103 rotate as the front wheel 103 rotates. And the 3rd member 3 supported by the 1st and 2nd support members 6a and 6b rotates. That is, the third member 3 rotates as the front wheel 103 rotates. The rotation speed of the third member 3 is the same as the rotation speed of the front wheel 103.

Here, the value represented by _{N 3 / (N 1/2} ) represents the speed increasing ratio of the first member 1 in the rotational speed to the rotational speed of the third member 3. _{N 3 / (N 1/2} ) value of that set the value of N ₁ and N ₂ to be greater than 1, the rotational speed of the first member 1 greater than the rotational speed of the third member 3 can do. That is, the rotation of the first member 1 can be increased more than the rotation speed of the front wheel 103 that is the rotating portion. For example, when the the _{N 1} 28, _{N 2} and 56, _{N 3} to 42, the value of the speed increasing ratio _{N 3 / (N 1/2} ) is three. That is, the rotation speed of the first member 1 can be tripled with respect to the rotation speed of the third member 3.

  As the third member 3 rotates, the first member 1 rotates. As described above, the rotation speed of the first member 1 is larger than the rotation speed of the third member 3. And when the 1st member 1 rotates, an induction current flows into the coil member 4, and electric power is produced | generated. As described above, the bicycle generator 10 according to the embodiment can efficiently generate electric power because the rotation speed of the first member 1 is higher than that of the front wheel 103. Therefore, according to the embodiment, a bicycle generator that is smaller than a conventional bicycle generator can be realized.

  Furthermore, the bicycle generator 10 according to the embodiment magnetizes the claw part 221 by disposing the magnet 23 between the claw parts 221, and the magnet 23 and the claw part 221 constitute a second magnetic pole group. Can do. That is, the space between the claw portions 221 as a yoke included in the conventional bicycle generator is used as a space for arranging the magnets 23, and the claw portions 221 are magnetized to be a part of the magnetic poles of the second magnetic pole group. Therefore, the increase in the weight and volume of the second member 2 can be reduced. Therefore, a smaller and lighter bicycle generator can be realized.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to these, A various change is possible unless it deviates from the meaning of this invention.

Modification 1
In the above embodiment, the bicycle generator 10 is mounted on the front wheel 103 as a hub of the front wheel 103, but is not particularly limited thereto. For example, the bicycle generator 10 may be attached to the rear wheel 104 as a hub of the rear wheel 104.

Modification 2
FIG. 11 is a schematic view showing a bicycle generator 10 according to the second modification. As shown in FIG. 11, the bicycle generator 10 may be mounted around a crankshaft 107a (an example of a rotating part). Specifically, the crankshaft 107a is supported on the bottom bracket hanger 102a, which is a part of the frame 102 of the bicycle 101, via the third bearing member 7c.

  The second member 2 is disposed on the outer side in the radial direction than the crankshaft 107a. The second member 2 is rotatable around the central axis 107c. In the second modification, the central axis 107c is the central axis of the crankshaft 107a of the bicycle 101. The second member 2 is attached to the crankshaft 107a and rotates integrally with the crankshaft 107a.

  The third member 3 is disposed on the radially outer side than the second member 2. The third member 3 is not rotatable around the central axis 107c. Specifically, the third member 3 is fixed to the bottom bracket hanger 102a. The third member 3 only needs to be fixed around the central axis 107c so as not to rotate, and the fixing location and fixing method of the third member 3 are not particularly limited.

  The first member 1 is disposed on the outer side in the radial direction than the third member 3. The first member 1 is rotatable around the central axis 107c. Specifically, the first member 1 is supported by the third member 3 via the fourth bearing member 7d. As described above, in the bicycle generator 10 according to the second modification, the second member 2 can rotate about the central axis 107c, and the third member 3 cannot rotate about the central axis 107c. Other configurations are basically the same as those in the above embodiment, and thus the description thereof is omitted.

Modification 3
In the above embodiment, the third member 3 can rotate around the central axis 51 and the second member 2 cannot rotate around the central axis 51, but the present invention is not limited to this. The second member 2 and the third member 3 only need to be configured to rotate relatively around the central axis 51. For example, the second member 2 may be configured to be rotatable around the central axis 51, and the third member 3 may be configured to be non-rotatable around the central axis 51.

Modification 4
As shown in FIG. 12, the support member 6 may further include a connecting member 63. The connecting member 63 connects the first support member 6a and the second support member 6b. The connecting member 63 extends in the axial direction between the first support member 6a and the second support member 6b. One end of the connecting member 63 is fixed to the first support member 6a. The other end of the connecting member 63 is fixed to the second support member 6b.

  The connecting member 63 is cylindrical. The connecting member 63 is disposed on the radially outer side of the first member 1. The connecting member 63 is disposed with a space from the first member 1.

Modification 5
In the said embodiment, although the supporting member 6 is comprised from the 1st supporting member 6a and the 2nd supporting member 6b, it is not limited to this in particular. For example, as shown in FIG. 13, the support member 6 can be configured to have one cylindrical portion 61 and a pair of flange portions 62 a and 62 b. A plurality of groove portions 611 are formed on the inner peripheral surface of the cylindrical portion 61. Each groove part 611 is arrange | positioned at intervals in the circumferential direction, and is extended in the axial direction. Moreover, each groove part 611 has penetrated to radial direction. Each magnetic body 31 is accommodated in each groove 611.

Modification 6
In the above embodiment, the yoke portion 22 is composed of the first yoke portion 22a and the second yoke portion 22b, but is not particularly limited thereto. For example, the yoke part 22 may be composed of only one of the first yoke part 22a and the second yoke part 22b. In this case, each magnet 23 is disposed between each first claw portion 221a or between each second claw portion 221b.

Modification 7
As shown in FIG. 14, each magnetic body 31 may have an insulating film 312 between each magnetic piece 311. For example, an insulating film 312 may be formed on each main surface of each magnetic piece 311, or an insulating film 312 may be formed on the entire surface of each magnetic piece 311.

DESCRIPTION OF SYMBOLS 1 1st member 12 Magnetic pole 2 2nd member 3 3rd member 31 Magnetic body 311 Magnetic body piece 312 Insulating film 4 Coil member 5 Hub axis 51 Center axis 6 Support member 6a 1st support member 6b 2nd support member 611a 1st insertion Hole 611b Second insertion hole 63 Connecting member 7a First bearing member 7b Second bearing member

Claims (22)

A bicycle generator that generates electricity based on rotation by a rotating part of the bicycle,
A first member having a first magnetic pole group including a plurality of magnetic poles arranged so as to have different polarities alternately in the circumferential direction, and rotatable around a central axis;
A second member having a second magnetic pole group including a plurality of magnetic poles arranged alternately to have different polarities in the circumferential direction;
A plurality of magnetic bodies arranged at intervals in the circumferential direction, and a third member arranged between the first member and the second member in the radial direction;
A coil member configured to cause an induced current to flow by rotation of the first member;
With
By the rotation of the rotating part, the second member and the third member are configured to rotate relatively around the central axis,
Each of the magnetic bodies has a plurality of magnetic body pieces stacked in the circumferential direction.
Bicycle generator.
Each of the magnetic pieces has a radial dimension larger than the circumferential dimension.
The bicycle generator according to claim 1.
Each magnetic body further includes an insulating film disposed between the magnetic pieces.
The bicycle generator according to claim 1 or 2.
Each of the magnetic bodies has a radial dimension larger than the circumferential dimension.
The bicycle generator according to any one of claims 1 to 3.
The number of magnetic poles of the second magnetic pole group is greater than the number of magnetic poles of the first magnetic pole group.
The bicycle generator according to any one of claims 1 to 4.
The axial length of each magnetic body is longer than the axial length of the first magnetic pole group,
The bicycle generator according to any one of claims 1 to 5.
The axial length of each magnetic body is longer than the axial length of the second magnetic pole group,
The bicycle generator according to any one of claims 1 to 6.
A rotation member that is rotatable about the central axis by the rotation unit, and further includes a support member that supports the magnetic piece;
The bicycle generator according to any one of claims 1 to 7.
The support member has a plurality of insertion holes,
Each magnetic body piece is inserted into the insertion hole.
The bicycle generator according to claim 8.
The support member has a plurality of insertion holes,
Each magnetic body is inserted into each insertion hole,
The bicycle generator according to claim 8.
The support member includes a first support member and a second support member that are arranged at an interval in the axial direction and support both end portions of each magnetic piece.
The bicycle generator according to any one of claims 8 to 10.
The support member includes a first support member and a second support member that are arranged at intervals in the axial direction and support both end portions of each of the magnetic body pieces,
The first and second support members have the insertion holes,
The bicycle generator according to claim 9 or 10.
The support member further includes a connecting member that connects the first support member and the second support member;
The bicycle generator according to claim 11 or 12.
The support member is made of a nonmagnetic material or a nonconductive material,
The bicycle generator according to any one of claims 8 to 13.
A first bearing member disposed between the first member and the support member and rotatably supporting the first member with respect to the support member;
The bicycle generator according to any one of claims 8 to 14.
A hub axle,
A second bearing member disposed between the hub shaft and the support member and rotatably supporting the support member with respect to the hub shaft;
Further comprising
The bicycle generator according to any one of claims 8 to 15.
The second bearing member is disposed radially inward of the first bearing member;
The bicycle generator according to claim 16, which is dependent on claim 15.
18. The bicycle generator according to claim 1, wherein each of the magnetic bodies is disposed between the first magnetic pole group and the second magnetic pole group in a radial direction.
The number of the magnetic body, the number of magnetic poles in the first magnetic pole group and N _1, when the number of magnetic poles of the second pole group was N _{2,
N 3 = N 2/2 ±} N 1/2
An integer N ₃ represented by:
The bicycle generator according to any one of claims 1 to 18.
One of the second member and the third member can be rotated around the central axis by rotation of the rotating part,
The other of the second member and the third member is not rotatable around the central axis.
The bicycle generator according to any one of claims 1 to 19.
A bicycle generator that generates electricity based on rotation by a rotating part of the bicycle,
A first member having a first magnetic pole group including a plurality of magnetic poles arranged so as to have different polarities alternately in the circumferential direction, and rotatable around a central axis;
A second member having a second magnetic pole group including a plurality of magnetic poles arranged alternately to have different polarities in the circumferential direction;
A plurality of magnetic bodies arranged in the circumferential direction, and a third member disposed between the first member and the second member in the radial direction;
A coil member configured to cause an induced current to flow by rotation of the first member;
With
By the rotation of the rotating part, the second member and the third member are configured to rotate relatively around the central axis,
Each of the magnetic bodies has a radial dimension larger than a circumferential dimension.
Bicycle generator.
At least one of the magnetic bodies includes a plurality of magnetic pieces that are stacked in a radial direction.
The bicycle generator according to claim 21.

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