Abstract: A derailleur for a bicycle, comprising a derailleur body provided with a fixing member and a four link parallelogram mechanism, the derailleur body being supported swingably with respect to the fixing member, and between the fixing member and the derailleur body is interposed an intermittent feed mechanism, so that a control wire is operated to allow the derailleur body to swing intermittently corresponding to the speed change stages with, respect to the fixing member, and thereafter, the link mechanism at the derailleur body is transformed, thereby switching a driving chain to a desired one of multistage sprockets.

Abstract: A front derailleur for a bicycle has a base member provided with a horizontal mount and a pair of linkage members disposed longitudinally of the bicycle and extending horizontally, the linkage members being mounted on the mount swingably through first and second pivot shafts extending vertically, so that an air resistance against the linkage members is reduced during the bicycle's running, and a smooth speed can be obtained.

Abstract: A rear derailleur for a bicycle, which comprises a derailleur body and a changeover frame having a guide pulley and a tension pulley, and guard plates for preventing a driving chain from escaping meshing with each pulley. The front edge of the guard plate corresponding to the tension pulley is positioned radially inwardly from the outer periphery of the tension pulley and close to the center thereof, and a pulley cap is interposed between the tension pulley and the guard plate.

Abstract: A derailleur for a bicycle, which is so constructed that a movable member is supported to a base member through two linkage members, a changeover frame having two pulleys carrying thereon a driving chain is pivoted to the movable member, and a tension spring is interposed between the movable member and the changeover frame, so that the tension spring exerts tension on the driving chain, said changeover frame being subjected to resistance against its swinging motion in a direction opposite to the working direction of the tension spring, thereby swinging the changeover frame easily in the direction of working of the changeover frame, while, requiring more force in the reverse direction to the working thereof, thereby making swinging of the changeover frame in the working direction of the tension spring easy and more difficult in the swinging motion direction opposite to the working direction of the spring.

Abstract: This invention concerns a derailleur for a cycle, comprising a yoke provided with a chain-guide pinion and a chain-tensioning pinion

Abstract: Guide sprocket wheel comprising a plurality of teeth corresponding to the pitch of the chain, the tops of the teeth being chamfered on bevelled on the periphery and on the lateral faces of the wheel. The angles of incidence of the teeth are cut off by further chamfers or bevels around the profile of the teeth, which gradually reduce the thickness of the teeth from the base to the tops thereof.

Abstract: The invention relates to a selector device for the remote control of the position of a member 4 relative to a support 3 through a control means 8 acting at one end of a flexible traction coupling, particularly a cable 11, whose other end is connected, through connection means L, to said member 4. The connection means L comprise:a piece p provided with notches c whose number is at least equal to the number of positions to be given to said member 4;and means E, G, for moving the piece p, adapted to cooperate with the notches of this latter in response to the movements of the control means.

Abstract: A derailler system for a bicycle including a sprocket system having a plurality of drive sprockets and a chain for driving a wheel of the bicycle at different speeds is shifted by actuation of a movable carrier member having an idler sprocket rotatably mounted thereon for selectively shifting the chain into engagement individually with the drive sprockets. A guide system for guiding movement of the carrier member along a path essentially parallel with the axis of the driven wheel to urge the chain between individual sprockets is provided, with the guide system including a first and a second part thereof movable relative to each other. A shifting mechanism including a shift lever enables shifting of the movable carrier to a plurality of shifting positions corresponding with the drive sprockets. A cam is fixedly mounted on the first part of the guide system and a cam follower member including a cam follower is rotatably mounted on the second part of said guide system.

Abstract: This invention relates to a chainwheel derailleur for a bicycle, characterized in that at least one of the fingers of the fork member is mounted pivotally on an axis perpendicular to its plane.

Abstract: The derailleur comprises a finger member which bears on a cam surface. The finger member is carried by an arm of a parallelogram structure. The cam surface is provided on the support of the derailleur. Preferably, the cam achieves a tri-dimensional guiding of the finger member which carries a rotary roller.

Abstract: A derailleur for a bicycle, in which a supporting member is supported movably to a fixing member and a change-over frame is fixed swingably to the supporting member through a first horizontal shaft. The derailleur is characterized in that a second tubular shaft is sleeved onto the first shaft coaxially therewith, a first pulley is supported rotatably to the second shaft, a tubular chamber is formed between the outer periphery of the first shaft and the inner periphery of the second shaft, and a coiled tension spring is housed within the chamber, thereby reducing the overall lateral width of the derailleur.

Abstract: A derailler system for a bicycle including a sprocket system having a plurality of drive sprockets and a chain for driving a wheel of the bicycle at different speeds with the chain being shifted onto individual drive sprockets by movement of an idler sprocket. A movable carrier member has the idler sprocket rotatably mounted thereon for selectively shifting the chain and a guide system is provided for guiding movement of the carrier member along the path essentially parallel with the axis of the driven wheel. A shifting mechanism for actuating the guide system includes a shift lever enabling shifting of the movable carrier to a plurality of shifting positions corresponding with the drive sprockets and a cam follower member including a cam follower rotatably mounted on a first part of the guide system is arranged to engage a cam member mounted on a second part of the guide system which is movable relative to the first part.

Abstract: A connecting mechanism for two members of a bicycle derailleur is provided with first and second bearings interposed between a supporting tubular member provided at a first member, such as a base member or movable member of the derailleur, and a shaft provided at a second member, such as a bracket member or chain change-over cage, each of the first and second bearings comprising a tubular portion inserted between the inner periphery of the supporting tubular member and the outer periphery of the shaft and a flange portion opposite to an end face of the supporting tubular member. At least one of the first and second bearings is provided at the flange portion thereof with an annular groove opening at one axial side of the flange portion.

Abstract: A four link member derailleur for a bicycle, which comprises a fixing member, two linkage members, and a movable member having a chain guide, and a return spring is provided with a control element having a plurality of engageable portions corresponding to the number of speed change stages and with a retainer engageable with each engageable portion at the control element to retain the movable member in a desired speed stage. The control element and retainer cooperate during shifting such that if a stroke of a control cable supported to the retainer is less than a given length, the retainer retains its engagement with each engageable portion, while if the stroke is greater than the given length, the retainer disengages from the engageable portion.

Abstract: A speed-changing device for a bicycle, having a pantograph mechanism which comprises four members, a supporting member, two linkage members, and movable member, is pivoted through a horizontal spindle swingably to a bracket fixed to a fork end of the bicycle. A wire holder for securing one end of a control wire is provided at one of the two linkage members and movable member, and a wire guide for guiding the control wire is disposed at a position outward with respect to the common axis of a multi-stage sprocket and beyond a phantom straight line connecting the axes of the wire holder and horizontal spindle.

Abstract: A chain change gear for shifting a driving chain to engage a selected one of a set of chain wheels associated with a driven wheel such as the rear wheel of a bicycle includes an articulated lever, a guide piece and first and second joint blocks for transferring movement from the articulated lever to the guide piece. The first joint block is arranged to be fixed to the vehicle frame and the second joint block is arranged to be connected to a chain guiding and tensioning mechanism for moving the mechanism to shift the chain into engagement with the selected one of the chain wheels when the articulated lever is actuated. The guide piece has two first stub axles extending parallel to each other from opposite ends of the guide piece, and the articulated lever has two second stub axles which extend parallel to each other from opposite ends of the articulated lever.

Abstract: Disclosed is an improved front derailleur for a bicycle, of that type which comprises a fixing member, two linkage members and a movable member having a chain guide the derailleur being operated by a control wire to move the movable member for changing the bicycle speed. The fixing member is provided with an extension which extends therefrom downwardly of the bicycle frame and has a lowermost end positioned in the vicinity of a bottom bracket at the bicycle, the extension having at the lower end portion thereof a wire guide for guiding the control wire.

Abstract: A derailleur for a bicycle comprising four members: a stationary member, first and second linkage members and a movable member. They are arranged in the form of a pantograph mechanism. Associatd with this mechanism is a pivotal member and a spring means which may be attached to any one of the members except the second linkage member. A Bowden cable having an inner wire and an outer sheath is attached between the pivotal member and the second linkage member so that the spring means serves as both a return spring for the pantograph mechanism and as a lost motion connecting means when it is a not possible to immediately shift the derailleur.

Abstract: An improved front derailleur for a bicycle, is provided with a mounting nose extending from a base member of the derailleur and with a support mounted to the nose integrally therewith or independently thereof, the support including an insertion bore for a control wire and a socket for an outer sheath guiding the wire. The mounting nose and support have guide slots in continuation of the insertion bore and extending therefrom, the guide slot extending in a direction away from a linkage member of the derailleur. The guide slots have a length larger than the maximum wire deflection created when a control wire having no outer sheath is operated.

Abstract: This invention relate a derailleur gear-change assembly for a bicycle, comprising a support cage carrying a chain guide wheel and a chain tensioning wheel, and a support means for the cage, the support means being provided with a means for producing translatory movement of the cage under the action of a cable and for passing the chain from one sprocket wheel of a freewheel of the bicycle to another sprocket wheel.

Abstract: In a device for shifting the drive chain on a multi-speed bicycle, a unit having a plurality of concentrically arranged different diameter chain wheels is secured on the axle of the bicycle's driven wheel. A chain trained over one of the chain wheels, passes over a chain guide wheel, and is rotatably supported on a movable support member. By displacing the chain guide wheel, the chain can be moved onto a selected chain wheel. A linkage arrangement is connected to the movable support member and to an adjusting switch for selecting one of the chain wheels. The linkage arrangement includes a first linkage part connected to the movable support member and a second linkage part articulated to the first linkage part so that the two parts are movable relative to one another. A cam disc is mounted on the second linkage part and a cam disc follower is mounted on the first linkage part.

Abstract: A rear derailleur for a bicycle, which comprises a base member, two linkage members and a movable member, the movable member supporting one pulley plate having a guide pulley and tension pulley. The guide and tension pulleys provide separate guard plates respectively so that a gap is formed therebetween for allowing a driving chain to pass through the gap closed by the use of a tension spring.

Abstract: The present invention is directed to a bicycle speed change lever comprising a support shaft secured to a mounting member, a lever body pivotally mounted on the support shaft, and a click plate disposed adjacent the lever body so as to be slightly movable in opposite directions about the support shaft for presenting the alternative of two positional phases. A plurality of spaced circular holes are formed in the click plate and aligned in an arc of a circle, a steel ball is retained between a base portion of the lever body and the click plate so as to be disengageable with any one of the plurality of circular holes, and a phase converting mechanism for converting the positional phases of the click plate from one phase to the other and vice versa. The phase converting mechanism including an engaging member formed with the click plate and a switching member secured to the mounting member which cooperate to effect the phase converting only when the lever body is pivotally moved in a reverse direction.

Abstract: A derailleur in which a movable member is freely movable in its forward movement in a given range with respect to a base member without being subjected to action of a return spring, whereby when a control wire is pulled by a control lever, the stroke of the pull-operation, over the free rotation range, allows the movable member to move forward and the movable member, at the terminus of its forward movement, is movable forward freely within the given range such that it may be pulled by the tension of a bicycle chain engaging with a sprocket to complete a partially completed shifting operation.

Abstract: A derailleur for a bicycle, which is adapted to shift a driving chain to a selected one of two or more sprocket wheels by pushing or pulling a push-pull control wire. The derailleur is provided with at least one arm oscillating independently from a movable member in shifting one of the push-pull wire and an outer cable for the wire. The wire is secured to the arm and a spring is secured to the arm so that when the movable member is, in changing speed, loaded above a predetermined value, the arm is oscillated to prevent the wire from buckling. On the other hand, when the resistance is removed the energy stored in the spring by the oscillation of the arm allows the movable member to shift so that the driving chain may be shifted to a desired speed-changing stage.

Abstract: A front derailleur for a bicycle is of the link type and comprises four members of a fixing member, two linkage members and a movable member, one of the four members carrying a chain guard for preventing a driving chain from coming off a front gear. The chain guard comprises a mounting plate for mounting to one of the four members and at least one guard plate for preventing the chain from coming off of the gear.

Abstract: A four member derailleur is disclosed having a control element which includes a plurality of engageable portions corresponding to the number of speed change stages mounted to one of the four members and a retainer for engaging with or disengaging from the engageable portions to keep a movable member of the four members in a proper position. The derailleur also includes means for moving the retainer in the direction of disengaging from each of the engageable portions so that when the movable member returns, through action of a return spring, the retainer may disengage from each of the engageable portions allowing the return movement of a chain guide.

Abstract: A rear derailleur for a bicycle, which is provided with a holder connected between a fitting member fixed to the bicycle frame and a pantograph mechanism supported to the fitting member through a transverse stud. The holder offsets the position of a movable member with respect to the fitting member, or in other words, the position of the movable member with respect to each sprocket at the freewheel, so that when the movable member is moved axially of the freewheel to switch a driving chain to a selected sprocket, the movable member is moved radially of the freewheel. Therefore the movable member, when moved axially of the freewheel for switching a driving chain to a selected one of the sprockets, is moved radially of the freewheel.

Abstract: A bicycle rear derailleur which comprises a first shaft on which a guide pulley guard is pivotally mounted and resiliently urged in one direction, a second shaft supported by the guide pulley guard, an inner pulley rotatably mounted on the second shaft, a guide pulley rotatably mounted on the inner pulley, a tension link mounted at its upper end to the second shaft so as to be coaxially movable with the inner pulley and resiliently urged so as to be swingable in one direction, a tension pulley rotatably mounted on a third shaft which is supported by the tension link and a tension pulley guard.

Abstract: A front derailleur of the link type is described comprising a base member fixed to a seat tube by fixing means, two linkage members pivoted swingably to the base member, and a movable member pivoted to the linkage members and having a chain guide, the linkage members having first end portions pivoted to the base member and second end portions pivoted to the movable member, the second end portions being positioned upward from the seat tube with respect to the base member, the chain guide pivoted to the second end portions being supported upward from the base member, whereby when the linkage members swing, the chain guide moves axially with respect to the chain gears in a path curved upward in a circular arc.

Abstract: A front derailleur for a bicycle has a chain guide having two opposite guide plates spaced at an interval larger than the width of a driving chain and an outer guide plate of the two guide plates is provided with a chain face which is formed at a position substantially intermediate lengthwise and at an upper portion widthwise of the same and radially outward to a chain sprocket and projects toward an inner guide plate. The chain guide face and the inner surface of the inner guide plate are spaced at an interval slightly larger than the width of the driving chain and smaller than the interval between the two guide plates.

Abstract: A derailleur for a bicycle, which comprises four members, including a fitting member, two linkage members and a movable member, all movable with respect to each other. Between two of the members there is a device for positioning cages having chain-guide pulleys mounted on the movable member, whereby the derailleur enables the cages to be properly positioned and kept in the position at each speed-change stage of the bicycle so that an accurate and light speed-change operation may be performed.