TWI712248B - Generator for bicycle - Google Patents

Abstract

[Question] To provide a generator for bicycles that can efficiently generate electricity.　　[Solution] The 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) can rotate around the central axis. The first magnetic pole group of the first member (1) includes a plurality of magnetic poles, and the plurality of magnetic poles are arranged so as to have different polarities alternately in the circumferential direction. The second magnetic pole group of the second member (2) includes a plurality of magnetic poles, and the plurality of magnetic poles are arranged alternately in the circumferential direction to have different polarities. The magnetic bodies (31) of the third member (3) are arranged at intervals in the circumferential direction. The third member (3) is arranged between the first member (1) and the second member (2) in the radial direction. Each magnetic body (31) has a plurality of magnetic body pieces stacked in the circumferential direction.

Description

Generator for bicycle

[0001] The present invention relates to a bicycle generator.

[0002] Various bicycle generators have been proposed to generate electric power for driving motor parts such as headlights (refer to Patent Document 1). The bicycle generator uses the rotation of the rotating part of the bicycle, for example, the rotation of the wheels to generate electric power. [Prior Art Document] [Patent Document] 　　[0003] 　　[Patent Document 1] JP 2015-130782 A

[Problem to be Solved by the Invention] [0004] In the above-mentioned bicycle generator, when the third member is deformed and the third member and the second member rotate relative to each other, it may collide with the second member. [0005] Therefore, the subject of the present invention is to provide a bicycle generator capable of suppressing deformation of the third member. [Means for Solving the Problem] [0006] The bicycle generator of the first aspect of the present invention generates electricity by using the rotation of the rotating part of the bicycle. This bicycle generator includes a first member, a second member, a third member, and a coil member. The first member can rotate around the central axis. The first member has a first magnetic pole group. The first magnetic pole group includes a plurality of magnetic poles, and the plurality of magnetic poles are 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, and the plurality of magnetic poles are arranged so as to have different polarities alternately in the circumferential direction. The third member has a plurality of magnetic bodies, and the magnetic bodies are arranged at intervals in the circumferential direction. The third member is arranged between the first member and the second member in the radial direction. The coil member causes an induced current to flow by the rotation of the first member. The second member and the third member relatively rotate around the central axis due to the rotation of the rotating part. Each magnetic body has a plurality of magnetic body pieces stacked in the circumferential direction. [0007] With this structure, each magnetic body of the third member has a plurality of magnetic body pieces. Each magnetic body sheet is stacked in the circumferential direction. Therefore, the radial deformation strength of the third member is improved. As a result, even when centrifugal force acts on the third member, it is possible to suppress the third member from deforming in the radial direction. [0008] The radial dimension of each magnetic body piece is larger than the circumferential dimension. With this structure, the strength of the third member against radial deformation can be further improved. [0009] Each magnetic body further includes an insulating film arranged between the magnetic body pieces. With this structure, the eddy current loss of each magnetic body can be reduced. [0010] The radial dimension of each magnetic body is larger than the circumferential dimension. With this structure, the strength of the third member against radial deformation can be further improved. [0011] 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. With this structure, the first member can be rotated faster than the rotating part of the bicycle. As a result, the bicycle generator can efficiently generate electric power. [0012] The shaft length of each magnetic body is longer than the shaft length of the first magnetic pole group. With this structure, leakage current can be reduced. [0013] The shaft length of each magnetic body is longer than the shaft length of the second magnetic pole group. With this structure, leakage current can be reduced. [0014] The bicycle generator further includes a supporting member. The supporting member can be rotated around the central axis by the rotating part to support each magnetic body piece. With this structure, the third member can be further suppressed from being deformed in the radial direction by being supported by the supporting member. [0015] The support member has a plurality of insertion holes. Each magnetic body piece is inserted into the insertion hole. With this structure, by inserting each magnetic body piece into the insertion hole, it is possible to maintain the state where each magnetic body piece is stacked in the circumferential direction. [0016] Each magnetic body is inserted into each insertion hole. With this structure, by inserting each magnetic body into the insertion hole, it is possible to maintain the state where the magnetic body sheets are stacked in the circumferential direction. [0017] The support member has a first support member and a second support member. The first and second supporting members are arranged at intervals in the axial direction to support both ends of each magnetic body piece. With this structure, since both ends of the third member are supported by the first and second support members, the strength of the third member against radial deformation can be improved. [0018] The first and second support members have respective insertion holes. With this structure, the both ends of the third member are inserted into the respective insertion holes of the first and second support members to support the third member. [0019] The support member further includes a connecting member that connects the first support member and the second support member. With this structure, the torsion torque acting on the third member can be reduced. [0020] The support member is made of a non-magnetic material or a non-conductive material. With this structure, electricity can be efficiently generated. [0021] The bicycle generator further includes a first bearing member. The first bearing member is arranged between the first member and the support member, and supports the first member so as to be rotatable relative to the support member. With this structure, the first member can be rotated smoothly, so that electric power can be efficiently generated. [0022] The bicycle generator further includes a hub axle and a second bearing member. The second bearing member is arranged between the hub shaft and the support member, and supports the support member so as to be rotatable with respect to the hub shaft. With this structure, the support member can be rotated smoothly, so electric power can be efficiently generated. [0023] The second bearing member is arranged on the radially inner side of the first bearing member. With this structure, the bicycle generator can be miniaturized in the axial direction. [0024] Each magnetic body is arranged between the first magnetic pole group and the second magnetic pole group in the radial direction. With this structure, electricity can be efficiently generated. [0025] The number of magnetic bodies, when the number of magnetic poles of the first magnetic pole group is N ₁ and the number of magnetic poles of the second magnetic pole group is N ₂ , it is an integer represented by N ₃ =N ₂ /2±N ₁ /2 N ₃ . With this structure, the first member can be rotated at a faster rotation speed than the third member, so electric power can be efficiently generated. [0026] One of the second member and the third member can be rotated around the central axis by the rotation of the rotating part. The other of the second member and the third member cannot rotate around the center axis. With this structure, electricity can be efficiently generated. [0027] The bicycle generator of the second aspect of the present invention generates electricity by using the rotation of the rotating part of the bicycle. This bicycle generator includes a first member, a second member, a third member, and a coil member. The first member can rotate around the central axis. The first member has a first magnetic pole group. The first magnetic pole group includes a plurality of magnetic poles, and the magnetic poles are 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, and the magnetic poles are arranged 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 arranged between the first member and the second member in the radial direction. The coil member causes an induced current to flow by the rotation of the first member. The second member and the third member relatively rotate around the central axis due to the rotation of the rotating part. The radial dimension of each magnetic body is larger than the circumferential dimension. [0028] With this structure, the radial dimension of each magnetic body is larger than the circumferential dimension. Therefore, even when centrifugal force acts on the third member, the radial deformation of the third member can be suppressed. [0029] At least one of the magnetic bodies includes a plurality of magnetic body pieces stacked in the radial direction. With this structure, the radial deformation of the third member can be suppressed. [Effects of the Invention] [0030] The bicycle generator of the present invention can suppress deformation of the third member.

[0032] Hereinafter, embodiments of the bicycle generator of the present invention will be described with reference to the drawings. Fig. 1 is a side view of a bicycle 101 with a bicycle generator 10 installed. 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 crank shaft 107a and a pair of crank arms 107b. Each crank arm 107b is provided at both ends of the crank shaft 107a. [0033] Figure 2 is a front view of a 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 electricity based on the rotation of a front wheel 103 (an example of a rotating part) that is a wheel of the bicycle. [0034] FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. 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 in this order from the radially inner side. The bicycle generator 10 further includes a hub axle 5 and a support member 6. The central axis 51 of the hub axle 5 corresponds to the central axis of the present invention. In the following description, the so-called radial direction represents the radial direction of a circle centered on the central axis 51. The so-called circumferential direction represents the circumferential direction of a circle centered on the central axis 51. The so-called axial direction represents the direction in which the central axis 51 extends. [0035] As shown in FIG. 2, the hub axle 5 extends between the pair of front forks 108. The hub axle 5 is hollow (refer to Figure 3). The hub axle 5 is fixed to the front fork 108 by a quick release mechanism (not shown). A connector 111 is attached to the first end of the hub axle 5 (the left end in FIG. 2). The connector 111 is a member for supplying electric power from the coil member 4 to motor parts such as the headlight 110. [0036] As shown in FIG. 3, the second member 2 is mounted so as not to rotate relative to the hub axle 5. That is, the second member 2 cannot rotate about the center axis 51. The second member 2 has a second magnetic pole group, which includes a plurality of magnetic poles. The second member 2 will be described in detail below. [0037] FIG. 4 is a perspective view showing the second member 2 mounted on the hub axle 5. As shown in FIG. 4, the second member 2 has a yoke 22 and plural magnets 23. The yoke 22 includes a plurality of claws 221 extending in the direction of the center axis 51. The claw portions 221 are arranged at intervals in the circumferential direction. [0038] Each magnet 23 is arranged between each claw portion 221. Each magnet 23 extends in a direction along the central axis 51. In each magnet 23, one of the magnetic poles is arranged on the radially outer side, and the other magnetic pole is arranged on the radially inner side. In each magnet 23, the direction of the magnetic pole is the same. [0039] For example, each magnet 23 is arranged so that the N pole faces the radially outer side and the S pole faces the radially inner side. In this case, each claw portion 221 is magnetized so that the radial outer surface of each claw portion 221 becomes an S pole. Each magnet 23 may be arranged so that the S pole faces the radially outer side and the N pole faces the radially inner side. In this case, each claw portion 221 is magnetized so that the radially outer surface of each claw portion 221 becomes the N pole. The second magnetic pole group of the second member 2 is composed of a plurality of claws 221 and a plurality of magnets 23. The magnetic poles of the second magnetic pole group are arranged to have different polarities alternately in the circumferential direction. The second magnetic pole group is arranged on the radially outer side of the coil member 4. [0040] In detail, the yoke portion 22 has a plurality of yoke pieces 220. FIG. 5 is a front view of a yoke piece 220 mounted on the hub axle 5. As shown in FIG. 5, the yoke piece 220 has a claw portion 221, a base portion 222, and a connecting portion 223. For example, the yoke 220 can be formed of electromagnetic steel or the like. [0041] The base portion 222 extends along the central axis 51 and is in contact with the hub axle 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 portion 222 is in contact with each adjacent base portion 222 in the circumferential direction. The claw portion 221 has approximately 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 in the axial direction (the left end in FIG. 5 ). The plural yoke pieces 220 configured in this manner are arranged radially around the central axis 51. [0042] FIG. 6 is an exploded view of FIG. 4. In Fig. 6, the magnet 23 is not shown. The above-mentioned second member 2 will be described in further detail with reference to Fig. 6. As shown in Fig. 6, the yoke 22 is composed of a first yoke 22a and a second yoke 22b. [0043] The first yoke portion 22a has a first yoke piece 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 221 a corresponds to the claw portion 221, the first base portion 222 a corresponds to the base portion 222, and the first connection portion 223 a corresponds to the connection portion 223. Each first claw portion 221a extends in the first direction (rightward in FIG. 6) along the central axis 51. Each first base portion 222a also extends in the first direction along the center axis 51. [0044] The second yoke portion 22b has a second yoke piece 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 221 b corresponds to the claw portion 221, the second base portion 222 b corresponds to the base portion 222, and the second connection portion 223 b corresponds to the connection portion 223. The axial direction of the second yoke piece 220b is opposite to that of the first yoke piece 220a. That is, each second claw portion 221b extends in a second direction (left in FIG. 6) that is opposite to the first direction along the central axis 51. Each second base portion 222b also extends in the second direction along the center axis 51. The second connecting portion 223b extends in the radial direction, and connects the second claw portion 221b and the second base portion 222b at an end in the axial direction (the right end in FIG. 6). [0045] The first yoke portion 22a and the second yoke portion 22b are arranged so that each of the first claw portions 221a and each of the second claw portions 221b alternate in the circumferential direction. Each magnet 23 is arranged between each first claw portion 221a and each second claw portion 221b in the circumferential direction. The second magnetic pole group is composed of plural first claw parts 221 a, plural second claw parts 221 b, and plural magnets 23. The second pole set number of magnetic poles of magnetic poles N pole set ₂ after the first-mentioned N is greater than _1. That is, the number 221a, a plurality of the second claw portion 221b, and a plurality of first claw portions of a plurality of magnets 23 the total number of magnetic poles N pole set ₂ after the first-mentioned N is greater than _1. [0046] As shown in FIG. 6, the coil member 4 is wound around the central axis 51. In detail, the coil member 4 is wound around the central axis 51 in a state of extending between each claw portion 221 of the yoke portion 22 and the base portion 222. That is, in the second member 2, each claw portion 221 and each magnet 23 are arranged on the radially outer side of the coil member 4, and each base portion 222 is arranged on the radially inner side of the coil member 4. That is, the coil member 4 is wound around each base part 222. The coil member 4 causes an induced current to flow by the rotation of the first member 1. The coil member 4 has a cylindrical shape as a whole. [0047] FIG. 7 is a cross-sectional perspective view showing the first member 1, the third member 3, and the supporting member 6 in detail. As shown in FIG. 7, the third member 3 has a plurality of magnetic bodies 31. The magnetic bodies 31 are arranged to be spaced apart from each other in the circumferential direction. The third member 3 is arranged between the first member 1 and the second member 2 in the radial direction. Specifically, each magnetic body 31 is arranged between the first magnetic pole group and the second magnetic pole group in the radial direction. Each magnetic body 31 is arranged on the radially outer side of the second magnetic pole group. The third member 3 is rotatable about the central axis 51 by the rotation of the front wheel 103. [0048] As shown in FIGS. 8 and 9, each magnetic body 31 has a radial dimension larger than a circumferential dimension. That is, in a cross section orthogonal to the axial direction, the radial dimension of each magnetic body 31 is larger than the circumferential dimension of each magnetic body 31. [0049] As shown in FIG. 9, each magnetic body 31 has a plurality of magnetic body pieces 311. A plurality of magnetic body pieces 311 constituting each magnetic body 31 are stacked in the circumferential direction. For example, in this embodiment, the magnetic body 31 is formed by stacking three magnetic body pieces 311 in the circumferential direction. Each magnetic body piece 311 is formed in a plate shape. For example, each magnetic body piece 311 can be formed by electromagnetic steel plate. The radial dimension of each magnetic body piece 311 is larger than the circumferential dimension. That is, in the cross section orthogonal to the axial direction, the radial dimension of each magnetic body piece 311 is larger than the dimension in the circumferential direction. Specifically, each main surface of each magnetic body piece 311 is arranged to face the circumferential direction. The magnetic pieces 311 may be bonded to each other or not. When the magnetic body pieces 311 are not adhered to each other, they are supported by the supporting member 6 described later, so that the state in which a plurality of magnetic body pieces 311 constitute one magnetic body 31 is maintained. [0050] As shown in FIG. 3, each magnetic body 31 extends in the axial direction. Each magnetic body piece 311 similarly 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 shaft length of each magnetic body 31 is longer than the shaft length of the second magnetic pole group. [0051] As shown in FIG. 7, the supporting member 6 is a member for supporting each magnetic body 31. In detail, it is used to support a plurality of magnetic body pieces 311. The support member 6 is rotatable about the central axis 51 by the rotation of the front wheel 103 of the bicycle. The support member 6 is made of a non-magnetic material or a non-conductive material. For example, although the supporting member 6 can be formed of stainless steel or the like, it may be made of resin or ceramic as long as it has sufficient strength in a state supported by the front wheel 103 of the bicycle. The supporting member 6 is composed of a first supporting member 6a and a second supporting member 6b. The first support member 6a and the second support member 6b are arranged 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. [0052] 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 of the first insertion holes 611a is not penetrated, but may be made to penetrate. The first insertion holes 611a are formed to be spaced apart from each other in the circumferential direction. Each first insertion hole 611a is inserted into the first end portion (the left end portion in FIG. 7) of each magnetic body 31. In detail, the first end of each magnetic body 31 is fitted into each first insertion hole 611a. By inserting each magnetic body 31 into the first insertion hole 611a, the state in which a plurality of magnetic body pieces 311 are stacked in the circumferential direction is maintained. [0053] 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 and the first cylindrical portion 61a are formed integrally. 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. [0054] 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 plural second insertion holes 611b (an example of insertion holes) are formed on the first end surface (the left end surface in FIG. 7). The second insertion hole 611b is formed as a through hole, but it may be made not through. The second insertion holes 611b are formed to be spaced apart from each other in the circumferential direction. In each of the second insertion holes 611b, the second end (the right end in FIG. 7) of each magnetic body 31 is inserted. In detail, the second end of each magnetic body 31 is fitted in each second insertion hole 611b. The magnetic bodies 31 are 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. [0055] The second flange portion 62b is formed in a disc shape, and an opening 622 is formed in the center portion. The second cylindrical portion 61b is fitted into the opening 622 of the second flange portion 62b. Thereby, the second flange portion 62b and the second cylindrical portion 61b are formed integrally. The second flange portion 62b has a plurality of second spoke holes 621b. Each second spoke hole 621b is formed with an interval in the circumferential direction. The spokes 109 of the front wheel 103 are connected to the second spoke holes 621b. [0056] 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 axle 5 via one of the second bearing members 7b. A cover member 8 is arranged between the first support member 6a and the first shaft member 7a. A positioning member 9 is arranged between the hub shaft 5 and the first bearing member 7a. The second support member 6b is attached to the hub axle 5 via the other second bearing member 7b. With the second bearing member 7b, the third member 3 fitted to the support member 6 can rotate relative to the hub axle 5 and the second member 2. [0057] The cover member 8 is fitted into 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 axle 5, and its end surface is in contact with the first end surface of the second member 2 (the left end surface in FIG. 3). The second end surface of the second member 2 (the right end surface in FIG. 3) is in contact with the shoulder 52 of the hub axle 5. The shoulder 52 is for restricting the movement of the second member 2 in the axial direction. [0058] As shown in FIG. 7, the first member 1 is arranged on the radially outer side than the third member 3. The first member 1 is supported by the supporting 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 of the first bearing members 7a, and is supported by the second support member 6b via the other first bearing member 7a. By this first bearing member 7a, the first member 1 is supported so as to be rotatable with respect to the supporting member 6. That is, the first member 1 is rotatable relative to the third member 3 about the center axis 51. The first member 1 is supported by the support member 6 at the outer peripheral portion of the third member 3 through which the power of the front wheel 103 is transmitted, thereby allowing the first member 1 to reinforce the rigidity of the third member 3. [0059] FIG. 10 is a perspective view of the first member 1. As shown in Fig. 10, the first member 1 has a cover portion 11 and a first magnetic pole group. The outer cover 11 is formed in a cylindrical shape. The first magnetic pole group is attached to the inner peripheral surface of the cover portion 11. The entire first magnetic pole group has a cylindrical shape. The first magnetic pole group is arranged on the radially outer side of each magnetic body 31. The first magnetic pole group is composed of a plurality of magnetic poles 12. The magnetic poles 12 are arranged to have different polarities alternately in the circumferential direction. In detail, the first magnetic pole group is composed of one or more magnets. The magnetic poles 12 of the magnets are arranged so as to be alternately different in the circumferential direction. Each magnetic pole 12 extends in the axial direction. The number of magnetic poles of the first magnetic pole group is the same as the number of the plurality of claws 221 of the yoke 22. That is, the number of magnetic poles 12 is the same as the total number of the first claws 221a and the second claws 221b. [0060] As shown in FIG. 8, the number of magnetic bodies 31 of the third member 3 is an integer N ₃ represented by N ₃ =N ₂ /2±N ₁ /2. N ₁ is the number of magnetic poles of the first magnetic pole group, that is, it represents the number of magnetic poles 12. N ₂ is the number of magnetic poles of the second magnetic pole group, that is, it represents the total number of the number of first claw portions 221 a, the number of second claw portions 221 b, and the number of magnets 23. In other words, in the case of the example shown in Fig. 8, the first magnetic pole group has 28 magnetic poles N _{1 and} is composed of 14 magnetic pole pairs. The number of magnetic poles N ₂ of the second magnetic pole group is 56. Therefore, N _{3 is} set to 42. Set N ₁ and N _{2 in such} a way that N ₃ /(N ₁ /2) is greater than 1. [0061] In the bicycle generator 10 configured as described above, by rotating the front wheel 103, the first and second support members 6a and 6b connected to the spokes 109 of the front wheel 103 are rotated. Then, the third member 3 supported by the first and second support members 6a, 6b is rotated. That is, by rotating the front wheel 103, the third member 3 is rotated. The rotation speed of the third member 3 is the same as the rotation speed of the front wheel 103. [0062] Here, the value represented by the above-mentioned N ₃ /(N ₁ /2) represents the increase ratio of the rotation speed of the first member 1 to the rotation speed of the third member 3. By setting the values of N ₁ and N ₂ such that the value of N ₃ /(N ₁ /2) is greater than 1, the rotation speed of the first member 1 can be made greater than the rotation speed of the third member 3. In other words, the rotation speed of the first member 1 can be increased compared to the rotation speed of the front wheel 103 which is the rotating part. For example, when N ₁ is 28, N ₂ is 56, and N ₃ is 42, the value of the speed increase ratio N ₃ /(N ₁ /2) is 3. That is, the rotation speed of the first member 1 can be tripled with respect to the rotation speed of the third member 3. [0063] The first member 1 is rotated by rotating the third member 3. As described above, the rotation speed of the first member 1 is greater than the rotation speed of the third member 3. By rotating the first member 1, an induced current flows through the coil member 4 to generate electric power. In the bicycle generator 10 of the embodiment, the rotation speed of the first member 1 is higher than that of the front wheel 103, so that it can generate electric power more efficiently. According to the embodiment, it is possible to achieve a smaller bicycle generator than the conventional bicycle generator. [0064] Furthermore, in the bicycle generator 10 of the embodiment, by arranging the magnet 23 between the respective claw portions 221 and magnetizing the claw portion 221, the magnet 23 and the claw portion 221 can constitute a second magnetic pole group. That is, the space between the claws 221 as the yoke of the conventional bicycle generator is used as a space for arranging the magnets 23, and the claws 221 are magnetized and used as part of the magnetic poles of the second magnetic pole group. The weight of the second member 2 can be reduced and the increase in volume can be reduced. Therefore, a smaller and lighter bicycle generator can be achieved. [Modifications] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the spirit of the present invention. [0066] Modification 1 In the above embodiment, the bicycle generator 10 is attached to the front wheel 103 as the hub of the front wheel 103, and is not particularly limited. For example, the bicycle generator 10 may be attached to the rear wheel 104 as the hub of the rear wheel 104. [0067] Modification 2 FIG. 11 is a schematic diagram showing a bicycle generator 10 of Modification 2. As shown in FIG. 11, the bicycle generator 10 may be installed around the crankshaft 107a (an example of a rotating part). Specifically, the crankshaft 107a is supported by a part of the frame 102 of the bicycle 101 via the third bearing member 7c, which is the bottom bracket suspension 102a. [0068] The second member 2 is arranged on the radially outer side of the crank shaft 107a. The second member 2 can rotate around the central axis 107c. In Modification 2, the so-called center axis 107c is the center 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. [0069] The third member 3 is arranged on the radially outer side than the second member 2. The third member 3 cannot rotate around the central axis 107c. Specifically, the third member 3 is fixed to the bottom bracket suspension 102a. The third member 3 may be fixed around the center axis 107c so as not to rotate, and the fixing location and fixing method of the third member 3 are not particularly limited. [0070] The first member 1 is arranged at a radially outer side than the third member 3. The first member 1 can rotate 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 of Modification 2, the second member 2 can rotate around the central axis 107c, and the third member 3 cannot rotate around the central axis 107c. The other structure is basically the same as the above-mentioned embodiment, so the description is omitted. [0071] Modification 3 In the above embodiment, the third member 3 is rotatable about the center axis 51, and the second member 2 is not rotatable about the center axis 51, and is not particularly limited to this. The second member 2 and the third member 3 may be relatively rotated around the central axis 51. For example, the second member 2 may be rotatable about the center axis 51, and the third member 3 may not be rotatable about the center axis 51. [0072] Modification 4 As shown in FIG. 12, the supporting member 6 may further have 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. [0073] The connecting member 63 has a cylindrical shape. The connecting member 63 is arranged on the radially outer side of the first member 1. The connecting member 63 is arranged at a distance from the first member 1. [0074] Modification 5 In the above-described embodiment, the support member 6 is composed of the first support member 6a and the second support member 6b, and is not particularly limited to this. For example, as shown in FIG. 13, the supporting member 6 may have a cylindrical portion 61 and a pair of flange portions 62a, 62b. Plural grooves 611 are formed on the inner peripheral surface of the cylindrical portion 61. The grooves 611 are arranged to extend in the axial direction at intervals in the circumferential direction. Each groove 611 penetrates in the radial direction. Each magnetic body 31 is accommodated in each groove 611. [0075] Modification 6 In the above-described embodiment, the yoke 22 is composed of the first yoke 22a and the second yoke 22b, and is not particularly limited to this. For example, the yoke 22 may be composed of only one of the first yoke 22a and the second yoke 22b. In this case, the magnets 23 are arranged between the first claws 221a or between the second claws 221b. [0076] Modification 7 As shown in FIG. 14, each magnetic body 31 may have an insulating film 312 between each magnetic body piece 311. For example, the insulating film 312 may be formed on each main surface of each magnetic sheet 311, or the insulating film 312 may be formed on the entire surface of each magnetic sheet 311.

[0077]1‧‧‧The first member 12‧‧‧Magnetic pole 2.‧‧The second member 3‧‧‧The third member 31‧‧‧Magnetic body 311‧‧‧Magnetic body sheet 312‧‧‧Insulating film 4‧ ‧‧Coil component 5‧‧‧Hub shaft 51‧‧‧Central axis 6‧‧‧Supporting member 6a‧‧‧First supporting member 6b‧‧‧Second supporting member 611a‧‧‧First insertion hole 611b‧‧‧ Second insertion hole 63‧‧‧Connecting member 7a‧‧‧First bearing member 7b‧‧‧Second bearing member

[0031] "Figure 1" is a side view of the bicycle of the embodiment.　　 Figure 2 is a front view of the bicycle generator according to the embodiment.　　 Figure 3 is a cross-sectional view taken along the line A-A in Figure 2. "Fig. 4" is a perspective view of the second member of the embodiment.　　 Figure 5 is a front view of the yoke piece of the embodiment.　　 Figure 6 is an exploded view of Figure 4. "Figure 7" is a cross-sectional perspective view of the first member, the third member, and the support member of the embodiment.　　 Figure 8 is a cross-sectional view taken along the line B-B in Figure 2. "Figure 9" is a perspective view of the magnetic body of the embodiment.　　 Figure 10 is a perspective view of the first member of the embodiment.　　 Figure 11 is a schematic diagram of a bicycle generator according to a modification.　　 Figure 12 is a cross-sectional view of a modified bicycle generator.　　 Figure 13 is a cross-sectional perspective view of a support member of a modification.　　 Figure 14 is a perspective view of a magnetic body of a modification.

1‧‧‧The first member

3‧‧‧The third component

4‧‧‧Coil component

10‧‧‧Alternator for bicycle

12‧‧‧Magnetic pole

221a‧‧‧The first claw

221b‧‧‧Second claw

23‧‧‧Magnet

31‧‧‧Magnetic

Claims (21)

A bicycle generator that uses the rotation of the rotating part of the bicycle to generate electricity; the bicycle generator includes: a first member, a second member, a third member, and a coil member; the first member can rotate around a central axis; The first member has a first magnetic pole group; the first magnetic pole group includes a plurality of magnetic poles, and the plurality of magnetic poles are arranged to alternate in a circumferential direction to have different polarities; the second member has a second magnetic pole group; the second magnetic pole group , Including a plurality of magnetic poles, the plurality of magnetic poles are arranged to alternate in the circumferential direction into different polarities; the third member has a plurality of magnetic bodies, and the plurality of magnetic bodies are arranged at intervals in the circumferential direction; Three members are arranged in the radial direction between the first member and the second member; the coil member allows induced current to flow by the rotation of the first member; the second member and the third member are arranged by the The rotation of the rotating portion causes relative rotation around the center axis; each of the magnetic bodies has a plurality of magnetic body pieces stacked in the circumferential direction. For example, the bicycle generator of the first item of the scope of patent application, wherein the above-mentioned radial dimension of each of the above-mentioned magnetic body pieces is larger than the above-mentioned circumferential dimension. For example, the bicycle generator according to the first or second patent application, wherein each of the above-mentioned magnetic bodies further includes an insulating film arranged between the above-mentioned magnetic body pieces. For example, the bicycle generator of item 1 or 2 of the scope of patent application, wherein the radial dimension of each of the magnetic bodies is larger than the circumferential dimension. For example, the bicycle generator of item 1 or 2 of the scope of patent application, wherein the number of magnetic poles of the second magnetic pole group is greater than that of the first magnetic pole group. For example, the bicycle generator according to the first or second patent application, wherein the shaft length of each magnetic body is longer than the shaft length of the first magnetic pole group. For example, the bicycle generator of item 1 or 2 of the scope of patent application, wherein the shaft length of each magnetic body is longer than the shaft length of the second magnetic pole group. For example, the bicycle generator of item 1 or 2 of the scope of the patent application further includes a supporting member; the supporting member can be rotated around the central axis by the rotating part to support each of the magnetic body pieces. For example, the bicycle generator according to the eighth patent application, wherein the supporting member has a plurality of insertion holes; and the magnetic body pieces are inserted into the insertion holes. For example, the bicycle generator according to the eighth patent application, wherein the support member has a plurality of insertion holes; and the magnetic bodies are inserted into the insertion holes. For example, the bicycle generator of claim 8, wherein the supporting member has a first supporting member and a second supporting member; the first supporting member and the second supporting member are arranged so as to be spaced apart in the axial direction. Used to support both ends of the above-mentioned magnetic body pieces. For example, the bicycle generator of claim 9, wherein the supporting member has a first supporting member and a second supporting member; the first supporting member and the second supporting member are arranged so as to be spaced apart in the axial direction. It is used to support both ends of each of the magnetic body pieces; the first support member and the second support member have the respective insertion holes. The bicycle generator according to claim 11, wherein the support member further includes a connecting member that connects the first support member and the second support member. For example, the bicycle generator of item 8 of the scope of patent application, wherein the supporting member is made of a non-magnetic material or a non-conductive material. For example, the bicycle generator of item 8 of the scope of patent application, which One step includes a first bearing member; the first bearing member is arranged between the first member and the support member, and supports the first member so as to be rotatable relative to the support member. For example, the bicycle generator of claim 8 further includes: a hub shaft and a second bearing member; the second bearing member is arranged between the hub shaft and the support member, and supports the support member as It can be rotated relative to the aforementioned hub axle. For example, the bicycle generator according to the 16th patent application, wherein the second bearing member is arranged on the radially inner side of the first bearing member. For example, the bicycle generator according to the first or second patent application, wherein each of the magnetic bodies is arranged between the first magnetic pole group and the second magnetic pole group in a radial direction. For example, the bicycle generator of item 1 or 2 of the scope of the patent application, wherein the number of the magnetic bodies, when the number of magnetic poles of the first magnetic pole group is N ₁ and the number of magnetic poles of the second magnetic pole group is N ₂ , is An integer N ₃ represented by N ₃ =N ₂ /2±N ₁ /2. For example, the bicycle generator of item 1 or 2 of the scope of patent application, of which, One of the second member and the third member can be rotated about the central axis by the rotation of the rotating portion; the other of the second member and the third member cannot be rotated about the central axis. A bicycle generator that uses the rotation of the rotating part of the bicycle to generate electricity; the bicycle generator includes: a first member, a second member, a third member, and a coil member; the first member can rotate around a central axis; The first member has a first magnetic pole group; the first magnetic pole group includes a plurality of magnetic poles, and the plurality of magnetic poles are arranged to alternate in a circumferential direction to have different polarities; the second member has a second magnetic pole group; the second magnetic pole group , Including a plurality of magnetic poles, the plurality of magnetic poles are arranged to alternate in the circumferential direction into different polarities; the third member has: a plurality of magnetic bodies arranged in the circumferential direction; the third member is arranged in the radial direction on the first Between the first member and the second member; the coil member allows an induced current to flow by the rotation of the first member; the second member and the third member are rotated around the center axis by the rotation of the rotating part Relative rotation; the radial dimension of each of the above-mentioned magnetic bodies is greater than the dimension in the circumferential direction, and at least one of the above-mentioned magnetic bodies is included in the radial stack The plural number of magnetic sheets.

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