Abstract:
A generator hub adapter is disclosed that is for use on a bicycle generator hub. The generator hub adaptor includes a mounting portion and a contact terminal. The mounting portion has a contact surface dimensioned and arranged to contact an axial outer face of a nut member of the generator hub. The mounting portion is electrically connectable to the nut member and easily mounted on a hub axle supporting the generator hub. The contact terminal is formed integrally with the mounting portion and provides a simple means for completing an electrical circuit without modification to a bicycle frame or the generator hub.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority to Japanese Patent Application No. 2005-016112, filed Jan. 24, 2005. The entire disclosure of Japanese Patent Application No. 2005-016112 is hereby incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to an electrical adapter, and more particularly relates to a generator hub adapter that is used with a bicycle generator hub, the bicycle generator hub including a hub axle, a stator portion of a generator mounted on the hub axle, a connector that is also held by a nut member to the hub axle, the connector being provided with a first contact terminal that is electrically connected to the stator portion of the generator, with the electrical adaptor also being supported on the hub axle and being electrically connected to a rotor portion of the generator.  
         [0004]     2. Background Information  
         [0005]     Bicycle generator hubs are well known. In such bicycle generator hubs, a stator portion of a generator is mounted within a hub located at the center of one of the bicycle wheels. The bicycle generator hub includes a hub axle, a stator portion of the generator and a connector. The stator portion of the generator is typically fixed or non-rotatably mounted to the hub axle. The stator portion is further electrically connected to a contact within the connector. The connector is preferably fixed by a nut member to the hub axle. The connector is typically an insulated member that includes the contact to allow for easy attachment of power supply wires from electrical devices such as a headlamp installed on a bicycle. In the past, the connector was mounted to the hub axle alongside the stator of the generator, and electrical wiring for connecting to the electrical device was connected to the contact of the connector (for example, see Japanese Laid-Open Patent Application 2004-299418). These connectors are known to come in a one-wire configuration having just a first contact terminal electrically connected via internal wiring to the stator of the generator. A rotor of the generator is typically grounded to the frame of the bicycle. Therefore, the frame of the bicycle served as a portion of the generator wiring to complete the circuit for powering devices mounted on the bicycle.  
         [0006]     A two-wire connector configuration having a first contact terminal electrically connected via internal wiring to one component of the generator, and a second contact terminal electrically connected via the hub axle to the other component of the generator is also known. In a two-wire connector configuration, the first contact terminal is generally the same as the one-wire configuration. The second contact terminal is achieved by attaching a second connector to the frame or hub axel, which is in electrical contact with the rotor of the generator.  
         [0007]     A one-wire type of connector makes wiring work easier because only one wire is needed to power the electrical device with the frame providing a ground. Accordingly, this design is widely employed for ordinary bicycles used for commuting to work or school, running errands, and so forth. However, two-wire connector having two (first and second) contact terminals is becoming widely desired in some markets because newer frames may not easily provide electrical conductivity. For example, some frames are provided with thick paint finishes that must be scratched down to metal in order to electrical contact. Further, some frames are made of composite materials which are non-conductive. Bicycles using such frames being equipped with electrical devices other than headlamps, such power assisted shifting mechanisms that require electrical power.  
         [0008]     The cost of producing two different designed hub generators, a one wire type and a two wire type, complicates manufacturing and makes each of the two types more expensive.  
         [0009]     In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved hub generator that is easily modified to change it to and from a one wire type to a two wire-type. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.  
       SUMMARY OF THE INVENTION  
       [0010]     One object of the present invention is to provide a bicycle with electric power that does not require the frame to be electrically conductive.  
         [0011]     Another object of the present invention is to provide two electrical connectors to complete a circuit from a bicycle hub generator.  
         [0012]     Another object of the present invention is to provide a bicycle hub generator with a simple design that can easily be installed on the bicycle for either a one wire or a two wire electrical connection configuration.  
         [0013]     It is also an object of the present invention to provide a generator hub adapter with which a one-wire type of connector having only one contact terminal can be easily changed to a two-wire type of a connector having two contact terminals.  
         [0014]     It is a further object of the present invention to provide a generator hub adapter with which, in changing a one-wire type of connector having only one contact terminal to a two-wire type of a connector having two contact terminals, the two contact terminals are aligned and adjacent to one another.  
         [0015]     The foregoing objects can basically be attained by providing a bicycle hub generator with first and second contact terminal that do not rely on the bicycle frame for completing electrical circuits on the bicycle.  
         [0016]     As discussed above, there are two types of connector used for generator hubs: a one-wire type having just one contact terminal where the frame completes a circuit, and a two-wire type having two contact terminals. The connector type needed for installation on the bicycle generator hub is determined by the specifications and intended application of the bicycle generator hub. In accordance with the present invention, a single bicycle generator hub configuration can be used for either a one wire or a two-wire type. The one wire type is easily modified in accordance with the present invention by the addition of an adaptor of the present invention. The adaptor of the present invention simplifies manufacturing costs because only a single hub generator configuration is manufactured and includes an optional adaptor of the present invention that turns the bicycle generator hub into a two wire connector.  
         [0017]     In accordance with one aspect of the present invention, a generator hub adapter is used with a bicycle generator hub, where the bicycle generator hub includes a hub axle, a stator of a generator and a connector, the stator being mounted to the hub axle and electrically connected to a first contact terminal supported on the connector, the connector being fixed by a nut member to the hub axle, the adaptor including a mounting portion and a second contact terminal. The mounting portion of the adaptor is in contact with an axial outer face of the nut member and is electrically connected to and mounted on the hub axle. The second contact terminal is formed integrally with the mounting portion.  
         [0018]     With the generator hub adapter of the present invention, when the connector is fixed to the hub axle by the nut member, the adapter is mounted to the hub axle in a state in which the mounting portion is in contact with the outer face of the nut member from the outside in the axial direction. As a result, the adapter and the hub axle are electrically connected via the nut member, with the nut member being threaded onto the hub axle and being at least partially covered by the adapter in the axial direction. The adapter is thereby electrically connected to a rotor of the generator. When an electrical wire is connected to the second contact terminal formed integrally on the mounting portion of the adaptor, a ground wire can be connected to the electrical device without having to use the frame of the bicycle. Since the adapter is disposed on an outer side of the nut member, the adapter having the second contact terminal can be mounted to the hub axle after the connector has been fixed to the hub axle. Accordingly, a second contact terminal can be easily added to the connector already fixed to the hub axle, where the connector has a first contact terminal. Therefore, the configuration of the generator hub can be easily changed to two contact terminal arrangement. This reduces the number of types of connectors necessary, and simplifies the manufacture of the connector and the assembly of the generator hub. Also, since an adapter may be added in the event that an electrical device requiring two contact terminals is subsequently added, retrofitting of an electrical device is easier.  
         [0019]     In another aspect of the present invention, the generator hub adapter further includes a locking portion that is formed integrally with the mounting portion for fixed attachment to the hub axle. In this case, since the second contact terminal of the adapter can be positioned with respect to the first contact terminal, the positional relationship of the two contact terminals is fixed, and the wiring for two terminals is easier.  
         [0020]     In another aspect of the present invention, the mounting portion of the generator hub adapter has a disk portion in contact with the nut member and equipped with a through hole through which the hub axle passes, and a cover portion that extends from the outer peripheral face of the disk portion toward the connector so as to allow coverage of the outer peripheral part of the nut member. In this case, since the mounting portion extends toward the connector so as to cover the nut member, the second contact terminal can be positioned close to the first contact terminal.  
         [0021]     In yet another aspect of the present invention, the generator hub adapter is used for a bicycle generator hub that has a hub axle, a generator component mounted to the hub axle and electrically connected at a first end to the hub axle, and a connector fixed to the hub axle and provided with a first contact terminal to which a stator of the generator is electrically connected, the adaptor including a mounting portion, a locking portion, and a second contact terminal. The mounting portion is electrically connected and mounted to the hub axle. The locking portion is formed integrally with the mounting portion and is fixed in position with respect to the hub axle. The second contact terminal is formed integrally with the mounting portion.  
         [0022]     With the above generator hub adapter, when the connector is fixed in position relative to the hub axle, the mounting portion is also fixed in position relative to the hub axle. As a result, the adapter and the hub axle are electrically connected, and the adapter is electrically connected to the rotor of the generator. When an electrical wire is connected to the second contact terminal formed integrally with the mounting portion, a ground wire can be connected to the electrical device without having to use the frame of the bicycle. Since the adapter is fixed with respect to the hub axle, the positional relationship between the first contact terminal and the second contact terminal on the adaptor is fixed. Therefore, in changing a connector having just one contact terminal to a connector having two contact terminals, the two contact terminals can be aligned, and the wiring for the two contact terminals can be more easily installed.  
         [0023]     In accordance with another aspect of the present invention, the connector is fixed by a nut member that is mounted to the hub axle from an outer axial direction, and the mounting portion of the adaptor is disposed between the nut member and the connector. In this case, since the adapter is fixed along with the connector to the hub axle by the nut member, the adapter will remain with the connector even if the hub axle is removed from the frame.  
         [0024]     In accordance with still another aspect of the present invention, the connector is non-rotatably mounted to the hub axle, and the locking portion of the adaptor includes a first locking portion that is non-rotatably engaged with the connector. In this case, since the adapter is locked with respect to the hub axle and is locked to the connector, it is less likely that the positional relationship of the two contact terminals will be disrupted. Also, the adapter can be elastically latched to the connector with the locking portion by using the first locking portion. In this case, the adapter will not readily come off the connector when the hub axle is removed from the frame even though the adapter is disposed to the outside of the nut member in the axial direction and is fixed to the hub axle by a nut or other such fixing means that fixes the hub axle.  
         [0025]     In accordance with another aspect of the invention, the connector has a flat face that is parallel to the hub axle, and the first locking portion of the adaptor is bent or biased inward such that the first locking portion makes contact with the flat face. In this case, since the first locking portion is bent inward, a biasing force is applied to the flat face of the connector, thereby urging the adaptor to remain in place on the connector.  
         [0026]     In accordance with still another aspect of the present invention, the second contact terminal of the adapter is aligned with the first contact terminal. In this case, since the two contact terminals are disposed lined up, it is easier to dispose the two electrical wires.  
         [0027]     In accordance with still another aspect of the present invention, the distal end of the second contact terminal extends away from the first contact terminal. In this case, since the distal end of the second contact terminal extends in a direction angled away from the first contact terminal, the distal ends of the two contact terminals are farther apart, so even with the two contact terminals located closer together, they can each be readily distinguished during wiring, and it will be easier to attach electrical wires to the contact terminals.  
         [0028]     With the present invention, since the adapter is disposed to the outside of the nut member in the axial direction, an adapter having a second contact terminal can be mounted to the hub axle after a first single connector has been fixed to the hub axle. Accordingly, a second contact terminal can be easily added to a connector that has been fixed to the hub axle, so a connector having just one contact terminal can be easily changed to a connector having two contact terminals. This reduces the number of types of connectors necessary, and simplifies the manufacture of the connector and the assembly of the generator hub. Also, since the adapter of the present invention may be added in the event that an electrical device requiring two contact terminals is subsequently added to the bicycle, retrofitting of an electrical device is easier.  
         [0029]     In accordance with still another aspect of the present invention, since the adapter is locked with respect to the hub axle, the positional relationship of the first contact terminal, which is provided to the connector fixed to the hub axle, and the second contact terminal is fixed. Therefore, in changing a connector having just one contact terminal to a connector having two contact terminals, the two contact terminals can be aligned, and the wiring for the two contact terminals can be installed more easily.  
         [0030]     These and other objects, features, aspects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the present invention. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0031]     Referring now to the attached drawings which form a part of this original disclosure:  
         [0032]      FIG. 1  is a side view of a bicycle that includes a generator hub in accordance with the present invention;  
         [0033]      FIG. 2  is a partial cross section of the generator hub showing a rotor and stator of a generator, a connector and an adaptor in accordance with a first embodiment of the present invention;  
         [0034]      FIG. 3  is a side view of the generator hub in accordance with the first embodiment of the present invention;  
         [0035]      FIG. 4  is an exploded view of a portion of the hub generator showing a portion of a hub axel, the connector and the adapter in accordance with the first embodiment of the present invention;  
         [0036]      FIG. 5  is a side view of the adapter in accordance with the first embodiment of the present invention;  
         [0037]      FIG. 6  is a cross section of the adaptor taken along the VI-VI line in  FIG. 5  in accordance with the first embodiment of the present invention;  
         [0038]      FIG. 7  is a cross section of the adaptor taken along the VII-VII line in  FIG. 5  in accordance with the first embodiment of the present invention; and  
         [0039]      FIG. 8  is an exploded view of a portion of a hub generator showing a portion of a hub axel, a connector and an adapter in accordance with a second embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0040]     Selected embodiments of the present invention will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the embodiments of the present invention are provided for illustration only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.  
         [0041]     Referring initially to  FIG. 1 , a bicycle  101  is illustrated in accordance with a first embodiment of the present invention.  
         [0042]     In  FIG. 1 , the bicycle  101  includes a frame  102  having a front fork  102   a , a handlebar  104 , a drive unit  105 , a front wheel (also referred to merely as the wheel)  106  having spokes  109 , and a rear wheel  107 . The drive unit  105  includes a chain, pedals, and other conventional bicycle drive train components.  
         [0043]     As shown in  FIG. 2 , the front wheel  106  of the bicycle  101  is provided with a generator hub  10  and a terminal adapter  60  which serves as a generator hub adapter in accordance with one embodiment of the present invention. The generator hub  10  serves to generate electrical power that is transmitted through two wires, a power supply wire  13   a  and a ground wire  13   b , to a headlamp  14  that can be equipped with, for example, a photosensor or a mechanical on/off switch.  
         [0044]     The generator hub  10  shown in  FIGS. 2 and 3  is mounted to the distal end of the front fork  102   a  along with the front wheel  106  of the bicycle. This generator hub  10  includes a hub axle  15 , a hub shell  18 , a generating mechanism  20  and a connector  22 . The hub axle  15  is fixed at each end to the front fork  102   a . The hub shell  18  is disposed about the outside of the hub axle  15  and is rotatably supported on the hub axle  15  by a pair of bearings  16  and  17 . The generating mechanism  20  is disposed between the hub axle  15  and the hub shell  18 . The connector  22  supplies power generated by the generating mechanism  20  to an external component such as the headlamp  14 . A terminal adapter  60  is mounted on the connector  22 .  
         [0045]     Around the outer peripheral end portions of the hub axle  15  are formed first male threaded components  15   a  and  15   b . A second male threaded component  15   c  is formed between the first male threaded components  15   a  and  15   b  and is larger in diameter than the first male threaded components  15   a  and  15   b . The outer peripheral surface of the hub axle  15  is also formed with a wiring insertion groove  15   d  that extends from the area where the generating mechanism  20  is mounted to the end of the first male threaded component  15   b . The wiring insertion groove  15   d  receives internal wiring  30  that connects the generating mechanism  20  and the connector  22 .  
         [0046]     Further, as shown in  FIG. 4 , the outer peripheral face of the hub axle  15  is also formed with a chamfered portion  15   e  that extends the length of the second male threaded component  15   c . The chamfered portion  15   e  prevents rotation of the generating mechanism  20  and the connector  22  with respect to the hub axle  15 .  
         [0047]     The hub axle  15  is non-rotatably fixed to the front fork  102   a  by fixing nuts  24  and  25  that thread onto the first male threaded components  15   a  and  15   b.    
         [0048]     With reference again to  FIG. 2 , the hub shell  18  has a main casing  31  and a pair of hub flanges  32  and  33 . The main casing  31  is a cylindrical member extending in the axial direction of the hub axle  15 , and has a bulging portion  31   a  on one side in the axial direction (to the right in  FIG. 2 ) that extends radially outward further than the left side portion of the main casing  31 . The hub flanges  32  and  33  are fixed to the outer peripheral face of the axial direction ends of the main casing  31  or integrally formed therewith. The hub flanges  32  and  33  are formed with a plurality of mounting holes  32   a  and  33   a  for mounting the inner ends of spokes  99  at equiangular spacing in the circumferential direction.  
         [0049]     The hub shell  18  is fixed to the hub axle  15  by hub cones  16   a  and  17   a  (the inner race of the bearings  16  and  17 ) that thread onto the first male threaded components  15   a  and  15   b , respectively, of the hub axle  15 . These hub cones  16   a  and  17   a  are locked in position by lock nuts  35  and  36 . The right lock nut  36  locks the hub cone  17   a  and also fixes the connector  22  to the hub axle  15 .  
         [0050]     The generating mechanism  20  is a claw-pole generator that includes a permanent magnet  41  and an inner fixing unit  42 . The permanent magnet  41  is fixed around the inner peripheral face of the hub shell  18  and generally constitutes a rotor of the generating mechanism  20 . The permanent magnet  41  being fixed to the hub shell  18  is further in electrical contact therewith. The hub shell  18  being in contact with the bearings (hub cones  16   a  and  17   a  and inner race of the bearings  16  and  17 ) is in electrical contact therewith. Further the bearings (hub cones  16   a  and  17   a  and inner race of the bearings  16  and  17 ) are in electrical contact with the hub axle  15 . As such, the permanent magnet  41  (the rotor of the generating mechanism  20 ) is in electrical contact with the hub axle  15  via the hub shell  18  and bearings.  
         [0051]     The inner fixing unit  42  generally constitutes a stator of the generating mechanism  20 . The inner fixing unit  42  is disposed within the inner peripheral part of the permanent magnet  41  and is non-rotatably fixed to the hub axle  15 . More specifically, the permanent magnet  41  is fixedly attached to the inner face of the bulging portion  31   a  of the main casing  31  of the hub shell  18  and rotates with the hub shell  18  and the front wheel  106 . The permanent magnet  41  preferably includes four magnet sections divided equidistantly in the peripheral direction. The permanent magnet  41  has alternating sections that are equidistantly spaced apart with alternating portions magnetized to north and south poles. The permanent magnet  41  encircles an outer periphery of a yoke  46  that is described in greater detail below.  
         [0052]     As shown in  FIG. 2 , the inner fixing unit  42  has a ring-shaped coil  44  and the above mentioned yoke  46  that surrounds the outer periphery of the coil  44 . The coil  44  and the yoke  46  are non-rotatably fixed to the hub axle  15  such that they are sandwiched by a pair of mounting nuts  48   a  and  48   b  that thread onto the second male threaded component  15   c . The coil  44  and yoke  46  are positioned such that they are disposed within the bulging portion  31   a  in the axial direction.  
         [0053]     The coil  44  is wound around a bobbin  50  in a conventional manner. The bobbin  50  has a cylindrical body  52  and first and second flanges  54   a  and  54   b . The cylindrical body  52  and flanges  54   a  and  54   b  form an annular troth open radially outward into which the coil  44  is wound. The flanges  54   a  and  54   b  are formed at opposite axial ends of the body  52 . A first end of the coil  44  is electrically connected to the hub axle  15 , while the second end is electrically connected to the internal wiring  30 .  
         [0054]     The yoke  46  includes a plurality of sets of first laminated yokes  53   a  mounted so as to be fitted onto the first flange  54   a  of the bobbin  50 , and a plurality of sets of second laminated yokes  53   b  similarly mounted so as to be fitted onto the second flange  54   b  of the bobbin  50 . The first laminated yokes  53   a  and the second laminated yokes  53   b  generally encircle the bobbin  50  in an alternating manner.  
         [0055]     As shown in  FIGS. 3 and 4 , the connector  22  is fixed to the hub axle along with the hub shell  18  by the lock nut  36 , as mentioned above. The connector  22  is a fairly thick disk-shaped member, and has a first contact terminal  26  electrically connected via the internal wiring  30  to the second end of the coil  44 . The first contact terminal  26  is, for example, a terminal connected to the power supply wire  13   a  of the headlamp  14 . The connector  22  is formed with a pair of protrusions  22   c  and  22   d  that extend outward at off center positions with respect to the connector  22  and the hub axle  15 . The protrusions  22   c  and  22   d  are formed on either peripheral side of the first contact terminal  26 . In other words, the first contact terminal  26  is extends outward between the protrusions  22   c  and  22   d . The connector  22  has a linear first flat face  22   a  oriented generally parallel to the hub axle  15 . The first flat face  22   a  is formed on the protrusion  22   c  but extends beyond the protrusion  22   c  as indicated in  FIG. 4 . The connector  22  is also formed with a second flat face  22   b  disposed adjacent to the first flat face  22   a  but angularly offset therefrom. A center hole  22   e  is also formed in the connector  22 . The center hole  22   e  includes a flat portion that is configured to engage the chamfered portion  15   e  of the hub axle  15 . The flat portion of the center hole  22   e  ensures that the connector  22  is non-rotatably mounted to the hub axle  15 .  
         [0056]     As should be understood from the drawings and the description herein, the connector  22  made of non-conducting material, such as a plastic, polymer, composite or other non-conducting material. Within the connector  22 , the first connection  26  is made of conductive material for transmission of generated electrical power. In contrast, the terminal adaptor  60  entirely made of a conductive material.  
         [0057]     The terminal adapter  60  is provided as a second electrical terminal that with the first connection  26  of the connector  22  completes the circuitry to and from the generator hub  10 . The terminal adapter  60  is in direct contact with the hub axle  15  and the frame  102  which serve as a ground for the generator hub  10 . The terminal adapter  60  is formed, for example, by press molding a sheet of steel or similar metal that conducts electricity.  
         [0058]     As shown in FIGS.  4  thru  7 , the terminal adapter  60  has a mounting portion  62 , a second contact terminal  28  and an engagement section that includes first, second and third locking portions  64 ,  66 , and  68 . However, the terminal adaptor  60  is a one-piece, unitary member preferably formed of a homogeneous material, such as a metal or metal alloy. The mounting portion  62  is oriented to contact in the axial direction an outer face of the lock nut  36 . The second contact terminal  28  is formed integrally with the mounting portion  62 . The first, second and third locking portions  64 ,  66 ′, and  68  are formed integrally with the mounting portion  62  and are oriented such that the terminal adaptor  60  is locked in position with respect to the hub axle  15 .  
         [0059]     The mounting portion  62  is mounted on the hub axle  15  such that there is electrical conductivity therebetween. More specifically, the mounting portion  62  is electrically connected to the hub axle  15  by contact with the outer face of the lock nut  36  that threads onto the hub axle  15 . The mounting portion  62  includes a disk portion  62   a , a cover portion  62   b  and a washer portion  62   c . The disk portion  62   a  has a contact surface that is in contact with an axial end face of the lock nut  36 . The disk portion  62   a  also has a through hole  62   d  through which the hub axle  15  extends. The cover portion  62   b  extends from the outer peripheral face of the disk portion  62   a  toward the connector  22  so as to cover an outer peripheral part of the lock nut  36 . The washer portion  62   c  is formed at the distal end of the cover portion  62   b . The cover portion  62   b  is formed cylindrically so as to be capable of accommodating the lock nut  36  in its interior thereby at least partially covering the lock nut  36 . The washer portion  62   c  is disposed across from the side face of the connector  22 .  
         [0060]     The first locking portion  64  is part of the engagement section shaped and configured to non-rotatably engage a portion of the connector  22  when in contact with the first flat face  22   a  of the connector  22 .  
         [0061]     As shown in  FIG. 7 , the first locking portion  64  extends in a direction generally or almost perpendicular to and away from the washer portion  62   c  and away from the disk portion  62   a . Preferably, the first locking portion  64  is bent first at an acute angle α that is approximately 85 degrees with respect to the disk portion  62   a  and also includes a second bent or angle portion  64   a  that is offset by an angle β that is approximately 10 degrees radially outward from the first locking portion  64 . Therefore, the first locking portion  64  and the angle portion  64   a  define an angle γ that is approximately 165 degrees. The first locking portion  64  shaped in this way is arranged and configured to elastically latch onto the connector  22  when brought into contact with the first flat face  22   a.    
         [0062]     The second locking portion  66  is formed on a side of the terminal adaptor  60  opposite the first locking portion  64  with the through hole  62   d  roughly centered therebetween. The second locking portion  66  is formed such that it extends away from the washer portion  62   c  and almost parallel to the first locking portion  64 , but more preferably, the second locking portion  66  extends at an angle approximately 90 degrees away from the washer portion  62   c , and in the same direction as the first locking portion  64 . The second locking portion  66  is disposed at a position where it can elastically contact and retain the connector  22  together with the first locking portion  64 . More specifically, a distance L between the angle portion  64   a  of the first locking portion  64  and the inner face of the second locking portion  66  is slightly smaller than the outside diameter of the portion corresponding to the connector  22 . Therefore, the first locking member  64  is configured to apply a biasing force on the connector  22  in combination with the second locking portion  66  contacting the connector  22 .  
         [0063]     Accordingly, the terminal adapter  60  is elastically latched, or grasped by the first locking portion  64  as well as being locked with respect to the connector  22  mounted non-rotatably to the hub axle  15 . In other words, the angle α of the first locking portion  64  causes the first locking portion  64  to be biased into firm contact with the connector  22 , locking the terminal adaptor  60  in position. More specifically, the first and second locking portions  64  and  66  constitute elastic latching components in addition to constituting locking portions with respect to the connector  22 . The third locking portion  68  is a part of the engagement section capable of engaging the second flat face  22   b . The terminal adapter  60  is locked with respect to the hub axle  15  and mounted non-rotatably to the connector  22  by the first and third locking portions  64  and  68 .  
         [0064]     The second contact terminal  28  is a terminal that is preferably connected to the ground wire  13   b  of the headlamp  14 . As shown in  FIG. 4 , the second contact terminal  28  is shaped so as to be aligned with the first contact terminal  26 . More specifically, the second contact terminal  28  extends in an axial direction away from the washer portion  62   c  and then bent to extend radially outward away from the outer face of the connector  22  so as to be lined up with but be a suitable distance away from the first contact terminal  26 . The second contact terminal  28  also extends in a different direction from the first contact terminal  26 . More specifically, as shown in  FIG. 3 , the second contact terminal  28  extends such that its distal end is angled away from the first contact terminal  26 . If the two contact terminals are too close together, they will be compact and attractive in appearance, but it will be difficult to connect the power supply wire or the ground wire. In view of this, in the first embodiment, the distal end of the second contact terminal  28  is disposed away from the first contact terminal  26 , so that even if the two contact terminals  26  and  28  are moved closer together in order to achieve a more compact size and a more attractive appearance, the first contact terminal  26  will still be readily distinguishable from the second contact terminal  28 , and it will be easy to connect the power supply wire  13   a  or the ground wire  13   b.    
         [0065]     With a generator hub  10  configured as described above, the terminal adapter  60  is mounted as dictated by the specifications and application. For instance, variations of the terminal adapter  60  may be required when mounted to a generator hub used for a sports bicycle. Further, variations of the terminal adapter  60  may be required if mounted to a generator hub to be exported to Europe. Further, the terminal adapter  60  can be mounted to a location on the bicycle  101  other than the generator hub  10  if used for other specifications or applications. Also, in retrofitting an electrical shifter, a controller for such a shifter, or another such electrical device, if the power supply needs to be a two-wire type of generator hub having two contact terminals, this can be easily accomplished merely by adding the terminal adapter  60 .  
         [0066]     The terminal adapter  60  can be installed in a state in which the assembly of the generator hub  10  is complete and the lock nuts  35  and  36  have been tightened. The mounting of the terminal adapter  60  is simply accomplished. More specifically, the terminal adapter  60  is mounted from the outer face of the lock nut  36  so as to cover the lock nut  36 , and the mounting is completed by elastically latching to the outer peripheral face of the connector  22  with the first to third locking portions  64 ,  66 , and  68 .  
         [0067]     Therefore, when the terminal adapter  60  is retrofitted, the power supply wire  13   a  is removed from the first contact terminal  26 , the fixing nuts  24  and  25  are removed, and the generator hub  10  is removed from the front fork  102   a  along with the front wheel  106 . The terminal adapter  60  is then mounted to the connector  22  from the outer face of the lock nut  36  of the generator hub  10 . The generator hub  10  is mounted to the front fork  102   a , the power supply wire  13   a  is connected to the first contact terminal  26 , and the ground wire  13   b  is connected to the second contact terminal  28 .  
         [0068]     With a terminal adapter  60  designed as described above, the terminal adapter  60  is disposed toward the outer side of the lock nut  36  and the terminal adapter  60  has the second contact terminal  28  mounted to the hub axle  15  after the connector  22  has been fixed to the hub axle  15 . Accordingly, the second contact terminal  28  can be easily added to the connector  22 , allowing a connector  22  having only one first contact terminal  26  to be easily changed to a connector  22  having two contact terminals  26  and  28 . This reduces the number of types of connectors  22  necessary, and simplifies the manufacture of the connector  22  and the assembly of the generator hub  10 . Also, since the terminal adapter  60  may be added in the event that an electrical device requiring two contact terminals  26  and  28  is subsequently added, retrofitting of an electrical device is easier.  
         [0069]     Also, since the terminal adapter  60  is locked with respect to the hub axle  15 , the positional relationship between the second contact terminal  28  and the first contact terminal  26  provided to the connector  22  is also fixed. Therefore, in changing a connector  22  having just one contact terminal  26  to a connector  22  having two contact terminals  26  and  28 , the two contact terminals  26  and  28  can be aligned, and the wiring for the two contact terminals  26  and  28  can be installed more easily.  
         [0070]     As used herein to describe the present invention, the following directional terms “forward, rearward, above, downward, vertical, horizontal, below and transverse” as well as any other similar directional terms refer to those directions of a bicycle equipped with the present invention. Accordingly, these terms, as utilized to describe the present invention should be interpreted relative to a bicycle equipped with the present invention.  
       Second Embodiment  
       [0071]     Referring now to  FIG. 8 , a connector configuration in accordance with a second embodiment will now be explained. In view of the similarity between the first and second embodiments, the parts of the second embodiment that are identical to the parts of the first embodiment will be given the same reference numerals as the parts of the first embodiment. Moreover, the descriptions of the parts of the second embodiment that are identical to the parts of the first embodiment may be omitted for the sake of brevity.  
         [0072]     In the first embodiment, the terminal adapter  60  was mounted on an outer face of the lock nut  36  in order to facilitate easy installation. However, as shown in  FIG. 8 , a terminal adaptor  160  may be disposed between the lock nut  36  and the connector  22 .  
         [0073]     The terminal adaptor  160  is formed, for example, by press molding a sheet of steel or other similar material that is a conductor. The terminal adapter  160  includes a mounting portion  162 , a second contact terminal  128  and first, second and third locking portions  164 ,  166 , and  168 . The mounting portion  162  is configured to contact an axial direction inner face of the lock nut  36 . The second contact terminal  128  is formed integrally with the mounting portion  162 . Further, the first, second and third locking portions  164 ,  166 , and  168  are formed integrally with the mounting portion  162  and engage the connector  22  thereby locking the terminal adaptor  160  in place with respect to the hub axle  15 .  
         [0074]     The mounting portion  162  is electrically mounted to the hub axle  15 . More specifically, it is electrically connected to the hub axle  15  by being brought into contact with the inner face of the lock nut  36  that threads onto the hub axle  15 . The mounting portion  162  has a disk portion  162   a  that is in contact with the lock nut  36  and a through hole  162   d  through which the hub axle  15  passes. A washer member  170  made of a synthetic resin, for example, is disposed between the disk portion  162   a  and the connector  22  providing insulation therebetween. The washer member  170  may be formed integrally with or separately from the terminal adapter  160 .  
         [0075]     The first, second and third locking portions  164 ,  166 , and  168  and the second contact terminal  128  are generally the same as the first, second and third locking portions  64 ,  66 , and  68  and the second contact terminal  28  in the above described first embodiment, therefore description of these elements will not be provided to avoid repetition.  
         [0076]     The terminal adapter  160  of the second embodiment is fixed to the hub axle  15  along with the connector  22  by the lock nut  36 . Accordingly, even if the hub axle  15  is removed from the front fork  102   a , the terminal adapter  160  will not come off the connector  22 . Therefore, the product can be shipped with the terminal adapter  160  already installed on the generator hub  10 .  
       Other Embodiments  
       [0077]     (a) In the above embodiments, the examples given were of a terminal adapter mounted to the generator hub on a front wheel, but can also be similarly mounted to the generator hub of a rear wheel.  
         [0078]     (b) In the above embodiments, the first and second contact terminals were angularly offset from one another extending is slightly different directions, but may instead be oriented to extend in the same direction parallel to one another. In this case, the wiring may be changed to dedicated two-wire use, allowing the power supply wire and ground wire to be connected to the first and second contact terminals at the same time.  
         [0079]     In understanding the scope of the present invention, the term “comprising” and its derivatives, as used herein, are intended to be open ended terms that specify the presence of the stated features, elements, components, groups, integers, and/or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and/or steps. The foregoing also applies to words having similar meanings such as the terms, “including”, “having” and their derivatives. Also, the terms “member” or “element” when used in the singular can have the dual meaning of a single part or a plurality of parts. Finally, terms of degree such as “substantially”, “about” and “approximately” as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed. These terms of degree should be construed as including a deviation of at least ±5% of the modified term if this deviation would not negate the meaning of the word it modifies.  
         [0080]     While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. Furthermore, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.