Abstract: A method for electronically servo-assisting a bicycle gearshift, including the steps of: a) driving an actuator of a bicycle gearshift to displace a chain of the gearshift in an axial direction with respect to a gearshift group comprising at least two sprockets; b) receiving information on the desired alignment between the chain and a predetermined sprocket of the gearshift group; and c) setting a biunique correspondence between the physical position of the actuator at step b) and a logic value associated with the gear ratio relative to the predetermined sprocket.

Abstract: A motorized bicycle gear shift device comprising a derailleur and an electric motor, associated directly with the derailleur, for controlling the derailleur and an electric transducer of absolute type, also associated with the derailleur for producing an electric signal indicative of the absolute position of the movable body of the derailleur.

Abstract: When a speed ratio (ip) at a stopping time of the vehicle cannot be stored, an operating position of a step motor (27) is initialized to a home position such that a primary pulley pressure (Ppri) is completely drained, a secondary pulley pressure (Psec) is increased to a predetermined pressure (P1), and a pulley ratio (the speed ratio (ip)) between a non-rotating primary pulley (2) and a non-rotating secondary pulley (3) is set at a lowest speed ratio. As a result, the primary pulley pressure (Ppri) is supplied reliably, and the startability of the vehicle improves.

Abstract: A mechanical arm transmission structure includes a tubular horizontal base, a drive belt wheel and a driven belt wheel mounted inside the horizontal base, a transmission belt mounted on the drive belt wheel and the driven belt wheel with the upper part thereof suspending above the horizontal base, a motor mounted outside the horizontal base for rotating the drive belt wheel through a speed reducer, a slide movable with the transmission belt along longitudinal rails at the top of the horizontal base and carrying a mechanical arm, and a holding down block fastened to the bottom side of the slide to affix the slide to the upper part of the transmission belt for allowing movement of the slide with the transmission belt along the longitudinal rails.

Abstract: An electric derailleur motor unit is provided for a motorized derailleur assembly. The electric derailleur motor unit has a derailleur motor support, a derailleur motor and an output shaft. The derailleur motor is mounted to the derailleur motor support. The output shaft is operatively coupled to the derailleur motor and rotatably supported on the derailleur motor support. The output shaft has an eccentric drive pin that is offset from a rotational axis of the output shaft. A drive train is provided between the derailleur motor and the output shaft. The drive train has at least one intermediate gear operatively coupled to the driving shaft of the derailleur motor and a worm gear operatively coupled to the intermediate gear such that rotation of the driving shaft of the derailleur motor rotates the intermediate gear which in turn rotates the worm gear.

Abstract: The apparatus of the present invention is adapted to supply power to one or more of the belt driven accessories of a hybrid electro-mechanical vehicle while the engine is off. Additionally, the power may be provided to multiple accessories with a single electric motor thereby saving the cost associated with manufacturing and installing a separate electric motor for each accessory. The apparatus includes an electric motor, a motor clutch, an engine clutch, and an accessory drive belt. When the engine is on, the accessory drive belt transfers torque from the engine crank shaft to the belt driven accessories. When the engine is off, the accessory drive belt transfers torque from the electric motor to the belt driven accessories.

Abstract: A bicycle derailleur comprises a first base member structured to be detachably mounted to a bicycle frame, wherein the first base member has a first abutment; a second base member structured to be mounted to the first base member, wherein the second base member has a second abutment that faces the first abutment of the first base member and the first and second base members define a housing space between them; a drive mechanism at least partially disposed in the housing space; a link mechanism that moves in response to movement of the drive mechanism; a chain guide coupled to the link mechanism for moving a chain among a plurality of sprockets; and a misalignment inhibiting structure disposed between the first base member and the second base member to inhibit misalignment of the drive mechanism as a result of an external force.

Abstract: A screw engagement portion between a pulley and a shaft is provided with a thread in a direction to increase the tightening torque when the pulley is driven. A breakable part broken by the axial tension produced when the tightening torque acting on the screw engagement portion is above a predetermined value, is also provided. The stress to break the breakable part is mainly a tensile stress. The tensile stress is substantially uniformly distributed in a cross section and, hence, the stress distribution of the breakable part can be relatively precisely predicted and analyzed. Consequently, the necessity of determining aspects of the breakable part, such as dimension, material, and the like, by trial and error is reduced. The breakable part can be broken without being subject to fatigue fracture.

Abstract: An electric derailleur has a motor unit having a derailleur motor with an output shaft, a position control mechanism and a controller. The output shaft is rotated through a moveable range including a first derailleur shift position and a second derailleur shift position. The position control mechanism is configured and arranged to provide a position signal indicative of an angular position of the output shaft. The controller detects a predetermined lockup position of the derailleur motor occurring at one of the first and second derailleur shift positions. The controller also sets a predetermined stop position for the derailleur motor that is calculated distance prior to the lockup position based on the position signal of the position control mechanism. Thus, the derailleur motor can be calibrated such that a new stop position is set that prevents an overcurrent from occurring in the motor.

Abstract: In order to transmit a torque from a hub 5 (rotating body) integrally formed together with a pulley 4 to, for example, a sleeve 6 inserted under pressure into a rotating shaft 1 of a refrigerant compressor 2, end surfaces 5e and 6a, which act as a bearing surface, are brought into frictional contact with each other. An axial pressing force is generated by the engagement of screws 1a and 5d of the rotating shaft 1 and the hub 5. An annular cut-out part 7, etc., is provided to form an annular space 10 in a part of the bearing surface around the rotating shaft 1. Thereby, the equivalent diameter of the bearing surface is increased, a slip is more unlikely to occur on the bearing surface, and it is therefore no longer necessary to apply an excessive pressing force to obtain a large friction torque.

Abstract: A power transmission system including an integrally molded hub and elastic member, where stress is inhibited from concentrating at the gate marks remaining after integral molding. In a pulley driven by a belt, a plastic pulley side relief section 1a provided at a pocket section of the pulley and a plastic hub side relief section provided on an iron outer ring of the hub engaged at the pocket section whereby power is transmitted from the pulley to the shaft. The hub side relief section and outer ring forming parts of the hub, the iron inner hub to be fastened to the shaft, and the plastic cylindrical part are integrally molded so that the gate mark for plastic injection is formed near to or further to the outer circumference of the outer ring.

Abstract: A powering system for a paper shredder carried by a vehicle having a two speed rear differential provides a power takeoff driven by a drive pulley irrotatably carried on a medial drive line shaft inserted between the vehicle forward and rearward drive line shafts. The range selector of the differential is modified to have a null position between speed ranges whereat rotational motion of drive line is not communicated through the rear differential to vehicle axles and wheels. An air bag carried powered by the vehicle pneumatic system selectively tensions and slackens drive belt tension to engage and disengage the power takeoff. Auxiliary apparatus to load unshredded paper into a storage area, feed the unshredded paper to the shredder and unload shredded paper from the vehicle are electrically powered by vehicle rechargeable batteries through switching means to regulate motor starting, stopping and reversing and to regulate shredder speed.

Abstract: An outboard motor engine and a protruding member for use therewith are provided. The outboard motor engine can have a crankshaft whose first end can be connected to a driven member. The protruding member can extend outwardly in the axial direction from a second end of the crankshaft and rotate about an axis with the crankshaft. A flywheel can be fixed on a protruding end side of the protruding member by a tightening member. A drive pulley can be fixed on a base side of the protruding member on the axis. The tightening member can be oriented eccentrically with respect to the drive pulley in the axial direction of the protruding member.

Abstract: A power transmission device includes a first one-way clutch that transmits a rotational power of a pulley to a rotating shaft, and a second one-way clutch that transmits a rotational power of a rotor of a motor to the rotating shaft. The first one-way clutch is of inner cam type in which an engagement cam-surface is formed in an outer periphery of a first inner ring, while the second one-way clutch is of outer cam type in which an engagement cam-surface is formed in an inner periphery of a second outer ring. This arrangement improves engagement performance of the first one-way clutch as well as reducing heat generation of the second one-way clutch, so that the lifetime of grease is prolonged.

Abstract: A bicycle front derailleur is configured to facilitate a chain returning to a sprocket during an upshifting operation if the chain drops off. The front derailleur basically has a fixed member, a chain guide and a moving mechanism. The fixed member can be fastened to a bicycle. The chain guide has an inner plate and an outer plate with a gap between the outer plate and the inner plate. The chain guide guides the chain between itself and the inner plate. The chain guide is free to move with respect to the fixed member. The inner plate has a first protruding part that protrudes toward the outer plate on the rear end, which is the chain entry side. The moving mechanism is a mechanism that is used to cause the chain guide to move.

Abstract: A bicycle derailleur is provided with a base member, a movable member, a linkage, a chain guide, an operating mechanism and an adjustment mechanism. The chain guide guides the chain. The movable member is a member that is used to support the chain guide. The linkage is pivotally connected at both ends to the base member and the operating member. The operating member causes the linkage to rotate. The adjustment mechanism is disposed between the linkage and operating member for adjusting the movement of the linkage.

Abstract: An apparatus for determining when to shift a bicycle chain from a first sprocket having a first number of teeth to a second sprocket having a second number of teeth comprises a memory for storing a reference value, and a processor that determines a shift value corresponding to a shift speed for shifting the chain from the first sprocket to the second sprocket by multiplying the reference value by one of the first number of teeth and the second number of teeth and dividing by the other one of the first number of teeth and the second number of teeth.

Abstract: An indexing and braking mechanism for a manual transmission having a shifting mechanism and at least one rotatable drive shaft is disclosed. The mechanism includes an indexing mechanism for controlling movement of the shifting mechanism between at least a first position and a neutral position. The indexing mechanism has a plate having a plurality of notches formed thereon, wherein one notch corresponds to the first position and another notch corresponds to the neutral position. A locking mechanism is provided for selectively limiting movement of one of the at least one rotatable drive shaft. The locking mechanism is adapted to selectively engage the plurality of notches to selectively maintain the indexing mechanism in one of the first position and the neutral position. The locking mechanism includes an indexing lever having a contact surface for contacting the rotatable drive shaft.

Abstract: A step motor positioning structure for a belt-type continuously variable transmission having a speed-change control valve for controlling a primary pressure to be supplied to a primary pulley, a servo link, and a step motor for driving, by way of the servo link, the speed-change control valve in response to a speed-change command signal is provided. The step motor positioning structure includes a motor bracket formed integral with the step motor and having an elongated hole and a circular hole, a bracket support supporting thereon the motor bracket, a first positioning member protruding outward from the bracket support and inserted in the elongated hole, and a second positioning member protruding outward from the motor support and inserted in the circular hole.

Abstract: A method for electronically servo-assisting a bicycle gearshift, including the steps of: a) driving an actuator of a bicycle gearshift to displace a chain of the gearshift in an axial direction with respect to a gearshift group comprising at least two sprockets; b) receiving information on the desired alignment between the chain and a predetermined sprocket of the gearshift group; and c) setting a biunique correspondence between the physical position of the actuator at step b) and a logic value associated with the gear ratio relative to the predetermined sprocket.

Abstract: The present invention comprises a pulley, a shaft body which is rotatable relative to the pulley and is concentrically disposed radially inside of the pulley, a one-way clutch which is interposed at an annular space between the pulley and the shaft body, a rolling bearing which is disposed in the annular space adjacent to the one-way clutch in an axial direction, an inner annular seal which is provided outside the rolling bearing in the annular space, and an outer annular seal which is provided outside the inner annular seal and has a proximal end portion and a distal end side lip. The proximal end portion of the outer annular seal is fixed to one of an inner peripheral surface of the pulley and an outer peripheral surface of the shaft body, and the distal end side lip of the outer annular seal contacts the other peripheral surface.

Abstract: Plural auxiliary devices such as a water pump and a generator coupled to a serpentine belt-drive system are driven by an internal combustion engine mounted on an automobile vehicle. The generator is divided into a first generator having a pulley in which a one-way clutch is installed and a second generator having a usual solid pulley. Fluctuations in the belt tension caused by changes in instantaneous rotational speed of the internal combustion engine are suppressed or reduced by the one-way clutch installed in the pulley of the first generator. An inertia torque of a rotor of the first generator may be made higher than that of the second generator because effects of the inertia torque on the belt tension fluctuations are alleviated by the one-way clutch.

Abstract: A decoupler for an alternator pulley in a serpentine drive system has a resilient, helical spring member that couples the alternator pulley with a hub structure through a spring retaining member. A bushing is disposed between the spring retaining member and the hub structure to facilitate sliding engagement therebetween. An annular sleeve member is disposed between the spring member and the alternator pulley to facilitate sliding engagement therebetween. The spring member is connected at one end thereof to the hub structure and connected at an opposite end thereof to the spring retaining member. The resilient spring member transmits the driven rotational movements of the alternator pulley by the serpentine belt to the hub structure such that the alternator shaft is rotated in the same direction as the alternator pulley while being capable of instantaneous relative resilient movements in opposite directions with respect to the alternator pulley during the driven rotational movement.

Abstract: A power transmission includes a first rotating member driven by an external drive source, an electromagnetic solenoid provided to the first rotating member, a second rotating member fixed to a main shaft of a rotary apparatus, and an mechanism for engaging and disengaging a plunger of the electromagnetic solenoid from the second rotating member. When the rotary apparatus is not used, the energy of the external drive source may be prevented from being wasted by interrupting the torque transmission from the first rotating member to the second rotating member by the operation of the mechanism for engaging and disengaging.

Abstract: A control apparatus for an electrically operated bicycle transmission comprises a power supply sensor and a control unit operatively coupled to the power supply sensor. The power supply sensor senses a power characteristic of a power supply, and the control unit provides a signal to operate the bicycle transmission when the power characteristic falls below a predetermined value. Alternatively, the control apparatus comprises a running condition time sensor and a control unit operatively coupled to the running condition time sensor. The running condition time sensor senses a time interval of a running condition of a bicycle, and the control unit provides a signal to operate the bicycle transmission to a predetermined gear ratio when the time interval of the running condition passes a selected value.

Abstract: A scooter drive arrangement which includes a first shaft, with a one-way bearing and a clutch, which is connected to a driven wheel, and a second shaft, which is rotated by an engine, through a centrifugal clutch, which has two fixed pulleys which respectively drive the clutch and the one-way bearing, through belts.

Abstract: A bicycle signal processing device includes a first bicycle signal processing element that generates a first signal having a first impedance, an external output terminal having an exposed output contact surface, and an impedance converting circuit coupled between the first bicycle signal processing element and the external output terminal for converting the first signal to a second signal having a second impedance at the external output terminal.

Abstract: An electronic control device for controlling a controlled device installed on a bicycle comprises a programmed computer that controls the control device. A reset circuit receives information related to a traveling condition of the bicycle and provides a reset signal to the computer in response to the occurrence of a predetermined traveling condition.

Abstract: A pulley unit includes a pulley and a rotor concentrically disposed for relative rotation, a one-way clutch interposed in an annular space therebetween, rolling bearings provided on opposite sides of the one-way clutch, and a seal ring for sealing the annular space. An inner diametrical surface of the pulley forms an outer ring raceway of the one-way clutch and the rolling bearing, and an outer diametrical surface of the shaft body forms an inner ring raceway of the one-way clutch and the rolling bearing. An outer diameter side of an annular portion of a retainer of the rolling bearing on the side of the seal ring is reduced so as to increase a storage volume of lubricating oil between the rolling bearing and the seal ring.

Abstract: A power transmission device for transmitting torque of a driving unit to a driven unit includes a first rotator, a second rotator, and a torque transmission member. The first rotator is to be driven for rotation by the driving unit. The second rotator is coupled to the driven unit. The torque transmission member is made of an elastically deformable material for making contact with the first rotator and the second rotator to transmit torque from the first rotator to the second rotator. An outer periphery of the torque transmission member includes a contact surface for making contact with the rotators and a non-contact surface out of contact with the rotators. The non-contact surface is provided with an oxygen permeance suppression layer made of a material having an oxygen permeability that is less than that of the contact surface.

Abstract: A motorized bicycle gear shift device comprising a derailleur and an electric motor, associated directly with the derailleur, for controlling the derailleur and an electric transducer of absolute type, also associated with the derailleur for producing an electric signal indicative of the absolute position of the movable body of the derailleur.

Abstract: In an automotive compressor, a pulley (6) is rotatably supported on a compressor housing (1) through a bearing (5) to have an axial gap (10) left between the compressor housing and the pulley. A waterproof cover (13) covers the axial gap and serves to suppress water from the outside from reaching the bearing. The waterproof cover is fixed to the compressor housing by a ring-shaped fastener (14). Instead of use of the waterproof cover, the axial gap may be controlled in size thereof.

Abstract: A structure of an automatic speed change device for bicycle gearbox is disclosed in this present invention. The above-mentioned design can be applied to a bicycle with a rear wheel speed change device. According to this invention, the automatic speed change device is able to control the allotting device of the rear wheel speed change device to transfer the chain into suitable gear by the treading rat of the user. This design can simplify the manual gear shifting process in the prior art for controlling the rear wheel speed change device. Therefore, this invention can make riding bicycle more easily and widely for all age.

Abstract: A power saving apparatus is provided for an assisting apparatus that uses power from a rotating member to assist the operation of a bicycle transmission. The power saving apparatus comprises a rotating member engaging member that moves between a rotating member engaging position and a rotating member disengaging position, a setting mechanism that sets the rotating member engaging member toward the rotating member engaging position, and a power saving unit. The power saving unit saves power communicated between the setting mechanism and the rotating member engaging member when the setting mechanism attempts to move the rotating member engaging member into the rotating member engaging position and the rotating member engaging member encounters a force that resists the rotating member engaging member being in the rotating member engaging position.

Abstract: A torque transmission device includes a pulley, a cylindrical member, a torque limiter and a weight member. The pulley is rotated by torque transmitted from a drive source. The cylindrical member is connected to a rotatable shaft of a compressor and is rotated integrally with the rotatable shaft. The torque limiter is arranged between the pulley and the cylindrical member and transmits the torque from the pulley to the cylindrical member. The torque limiter disables the transmission of the torque when the torque becomes equal to or greater than a predetermined value. The weight member is secured to the cylindrical member at a point closer to the rotatable shaft than the torque limiter.

Abstract: A power control apparatus for a bicycle that uses a first power supply and a second power supply to provide electrical power includes a voltage sensor for sensing a voltage from the first power supply. A control unit is coupled to the voltage sensor and is coupled for receiving power from the first power supply and the second power supply. The control unit outputs power from the second power supply when the voltage sensed by the voltage sensor is below a selected value, and the control unit outputs power from the first power supply when the voltage sensed by the voltage sensor is above the selected value.

Abstract: An assisting apparatus for using power from a moving member to assist the operation of a bicycle transmission comprises a power transfer mechanism, a drive coupling mechanism, and a position maintaining mechanism. The power transfer mechanism moves in one of a first direction and a second direction to upshift the bicycle transmission, and the power transfer mechanism moves in the other one of the first direction and the second direction to downshift the bicycle transmission. The drive coupling mechanism couples the power transfer mechanism to the moving member to move the power transfer mechanism in one of the first direction and the second direction, and the position maintaining mechanism prevents the power transfer mechanism from moving in the other one of the first direction and the second direction.

Abstract: A generator for alleviating fluctuations in instantaneous rotational speed of an internal combustion engine is included in a belt-drive system. When an average rotational speed of the generator is lower than a predetermined speed, for example, an idling speed, a generation torque of the generator is controlled to reduce the belt tension fluctuations. When the average speed of the generator is higher than the predetermined speed, the generator is controlled in a usual manner to supply a stable power to the electric loads.

Abstract: A method for electronically servo-assisting a bicycle gearshift to allow compensation for misalignments between the chain of a bicycle gearshift and one or more sprockets of the gearshift, the method including the steps of: driving an actuator of a bicycle gearshift to displace a chain of the gearshift in an axial direction with respect to a gearshift group comprising at least two sprockets; receiving information on the desired alignment between the chain and a predetermined sprocket of the gearshift group; and setting an adjustment variable, of a logic value associated with the gear ratio relative to the predetermined sprocket, to a value corresponding to the displacement carried out in the step of driving the actuator.

Abstract: A bicycle shift control device is adapted to be mounted to a bicycle equipped with an alternating current generator and a shifting device having a plurality of speed steps. The shift control device includes a power storage unit adapted to store electrical power from the alternating current generator; a shift control element operatively coupled for receiving electrical power from the power storage unit and for providing shift control signals for controlling the operation of the shifting device; and a case adapted to be mounted to the bicycle, wherein the case houses both the power storage unit and the shift control element.

Abstract: An electronic shift control apparatus is provided for a bicycle having a transmission with a plurality of speed stages. The apparatus comprises a shift unit that provides signals for shifting the transmission, a restriction selecting unit operated by a user to select a restricted speed stage, and a restricting unit operatively coupled to the shift unit and to the restriction selecting unit. The restricting unit prevents the shift unit from providing signals to shift the transmission to the restricted speed stage.

Abstract: A derailleur position processing apparatus includes a derailleur moving member that moves with the derailleur; an analog signal providing mechanism operatively coupled to the derailleur moving member, wherein the analog signal providing mechanism provides an analog position signal in response to movement of the derailleur moving member; and a digital signal providing mechanism operatively coupled to the derailleur moving member, wherein the digital signal providing mechanism provides a digital position signal in response to movement of the derailleur moving member.

Abstract: A transmission control unit that generates transmission commands for controlling the operation of the first transmission and the second transmission. The transmission control unit includes an inhibiting unit for inhibiting a second operation of the first transmission after a first operation of the first transmission.

Abstract: A two speed shift mechanism for a belt drive that includes a rotatable shaft with a first pulley, and a tube concentric with the shaft and rotatable therearound. The tube includes a shift hub supporting a second pushy in axially spaced relation to the first pulley for concentric rotation about the shift hub. The mechanism further includes a collar mounted around the shift hub for rotation therewith and for axial movement between a position adjacent the first pulley and a position adjacent the second pulley. In a first position, the collar and the first pulley include elements engageable for connecting the collar to the first pulley for rotation of the collar, the shift hub, and the tube. In a second position, the collar and the second pulley include elements engageable for connecting the collar to the second pulley for rotation of the collar, the shift hub, and the tube.

Abstract: A control device is provided for a bicycle having a transmission with a plurality of speed steps, wherein the control device includes a traveling condition signal receiver that receives traveling condition signals corresponding to a traveling condition value of the bicycle, a threshold value memory that stores a first threshold value of the traveling condition, and a processor that compares a plurality of the traveling condition values to the first threshold value and provides a first control signal for shifting the bicycle transmission when the plurality of traveling condition values pass the first threshold value.

Abstract: A chain drive for pivot chains (7) or round link chains (8) having spur gears (2) and a polygonal chain wheel (10) reduces variations in velocity and acceleration transferred to the chains (7), (8). The driven gear wheel (3a) and the driving gear wheel (4a) consist of noncircular gear wheels having a set gear ratio adjustment so that the driving gear wheel (4a) is put in such a position to the driven gear wheel (3a) so that the slowest angular velocity coincides with the corners (29a) of the polygon of the chain wheel (10) and the fastest angular velocity occurs at the middle of the polygon straight lines (29b) of the chain wheel.

Abstract: A control apparatus is provided for a bicycle shift control device that uses power from a rotating member to assist the operation of a bicycle transmission, wherein the shift control device includes an input transmission member that requests assistance of the rotating member and an output transmission member that is assisted by the rotating member. The control apparatus comprises an input transmission member drive member that moves at least to a neutral position, to an upshift position and to a downshift position; an input drive member position sensor operatively coupled to the input transmission member drive member; and a motor operatively coupled to the input transmission member drive member. A control unit is operatively coupled to the input drive member position sensor and to the motor to move the input transmission member drive member to at least one of the neutral position, the upshift position and the downshift position.

Abstract: In this driving force transmission apparatus, with a simple constitution employing a one-way clutch 20 instead of an electromagnetic clutch, the driving force derived from the motor 33 can be transmitted to the rotating shaft 1 during engine stops, and the driving force of the engine can be transmitted to the rotating shaft 1 during engine operations. Also, the pulley 3 is held against the connecting portion 11 and the fixed-side member 26 by means of first and second two ball bearings 21, 30 disposed axially adjacent to first and second inner cylinder portions 6, 7, respectively, between which the opening portion 5 of the pulley 2 is interposed. This simple driving force transmission apparatus can switch between transmission and non-transmission of driving force from pulley to rotating shaft, and transmits the driving force of a motor directly to the rotating shaft in the non-transmission state.

Abstract: A bicycle shift control device includes a shift signal output unit for outputting shift signals and an inhibiting unit operatively coupled to the shift signal output unit for inhibiting the output of a second shift signal after the output of a first shift signal. In a more specific embodiment, the inhibiting unit inhibits the output of the second shift signal for a predetermined standby time after the output of the first shift signal.

Abstract: A shift control apparatus for a bicycle transmission comprises a signal detector that detects signals corresponding to motion of the bicycle, a threshold setting unit that sets a shift threshold value, and a time interval calculating unit that calculates time intervals after signals are detected. A control unit provides a signal to change a gear in the bicycle transmission only after a time interval between successive first and second signals passes the shift threshold value and the second signal is detected by the signal detector.