JPS6311494A - Derailer for bicycle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

[Field of Application of Industry-1-] The second invention relates to a bicycle derailleur for changing a chain on a selected one of multi-stage sprockets, and a swinging link mechanism provided with an elastic The chain guide member attached to the movable member of the swing link mechanism is forcibly deformed by wire pulling and moved in parallel in the axial direction of the multi-stage splinter. The function of applying the return force of the swing link mechanism to the spring of
Swing link) It also has a function to store operating power in case the current structure is locked.

[Prior art and its problems]

This type of derailleur has a structure in which a chain guide member is supported via a swing link mechanism such as a so-called parallelogram pantograph link mechanism to a base member fixed to the frame. When the mechanism is deformed, the chain guide shaft moves parallel to the sprocket axial direction. In the case of a rear derailleur, the chain guide part is a swinging link mechanism with a replacement frame that supports two pulleys: a guide pulley and a tension pulley, on which chain 7, which is about to move JJ+, is suspended from a multi-stage freewheel. The movable member is resiliently biased in one direction around a support shaft parallel to the sprocket axis, and is rotatably supported. A pair of chain guides facing each other in the inner and outer directions are attached to the movable member of the swing link mechanism. When the swing link mechanism is deformed, the frame or chain guide moves in the axial direction of the sprocket, thereby displacing the chain that is about to attach to the sprocket in the width direction of the sprocket. The engagement is changed to a sprocket that corresponds to the axial position of the sprocket on the replacement frame or chain guide. ” - Deforming the swinging link mechanism [Yasaku usually connects the swinging link mechanism and the gear shift lever attached to the frame connection part with a cable, and transfers the rotation operating force of the gear shift lever via this cable. This is done by transmitting the signal to the swing link mechanism. Since it is convenient to use a so-called pull-type cable that can only transmit traction force from the viewpoint of ease of wiring and durability, the swing link mechanism is always urged in the return direction by a return spring. is normal. Therefore, the cable is connected to the swing link mechanism such that when the cable is pulled, the swing link mechanism is forcibly deformed against the return spring. As a result, when you operate the gear lever and pull the cable,
The swinging link is forcibly deformed in the direction of accumulating energy against the return spring, and when the cable is let out by operating the speed change lever in the opposite direction to the above, it is deformed by the elastic return force of the accumulating return spring. The swing link deforms back. As a result, the movable member supporting the chain guide member is reciprocated in conjunction with the reciprocating movement of the speed change lever. The above-mentioned return spring is usually made by inserting a torsion spring into a pin that connects the relatively pivotal parts 2 + 4 of the members constituting the swing link mechanism, and bringing both ends of the torsion spring into elastic contact with each of the two members. It is installed by. In such a spring mounting structure, when the swing link mechanism is deformed against the elasticity of the spring, the spring has a shape corresponding to the amount of relative pivoting of the two members. For example, two members are relatively 45
When pivoted by a degree, the spring is constricted in a helical direction of approximately 45 degrees. According to Hooke's law, a spring has a repulsive force proportional to the amount of torsional deformation, so if the amount of restriction in the pivoting range of the link mechanism is large, the spring repulsion at the beginning of the link mechanism's deformation and at the end of the deformation is The difference in force increases, which adversely affects shift operability. For example, a gear shift lever must have enough frictional resistance (sometimes click resistance) to resist the elasticity of a return spring on the derailleur side and be held at a desired rotational position. , it is necessary to determine the point at which the above-mentioned return spring has the greatest repulsive force as the W quasi, and therefore the rotational resistance of the gear shift lever must be set to be extremely large. However, the difference in stored repulsive force due to the amount of contraction of the return spring can be reduced by increasing the number of turns in the coil part of the torsion spring and extending the overall length of the strands, but this would make the coil spring itself extremely bulky. Problems arise in that assembly workability deteriorates, and the derailleur itself to which this bulky return spring is attached becomes large and heavy. In addition, if the above-mentioned cable for transmitting the operating force of the gear shift lever to the derailleur is directly connected to the swing link mechanism, when the bicycle is stopped, even if you try to move the movable member by operating the gear shift lever, it will not work. There will be an inconvenience that this cannot be done. This is because when the bicycle is stopped, the chain 7 is stopped, so the movement of the flexible member 11 is inhibited by being restrained by the stationary chain 7 hooked on one sprocket. By solving this problem, the gear shift lever can be operated even when the bicycle is stopped, and this operating force is temporarily stored in a spring inside the derailleur, allowing the chain to rotate and move the movable parts. Various models have been proposed that are equipped with a so-called saver mechanism that releases this stored force after the restraint is released and deforms the &-1 swing link mechanism to match the amount of operation of the gear shift lever. A representative example thereof is the one described in Japanese Patent Publication No. 11742/1983. In this device, an operating arm to which the end of the cable is fixed is provided on the swing link mechanism, and a spring is provided to bias the operating arm in one direction, and this spring and the swing link mechanism are attached in one direction. The force of the spring acts as a force, υte,
It is configured to exhibit a so-called saver function. However, in the configuration shown in the above-mentioned publication G, since it is necessary to equip two springs, the mechanism becomes complicated, and
The need to secure space for accommodating the spring has hindered the ability to make derailleurs more compact. Another problem is that it is difficult to balance the spring elasticity of the 2111i1. Furthermore, since it is necessary to further add an actuating arm to the members constituting the swing link, the mechanism becomes unavoidably complicated. This invention was conceived under the above circumstances,
The m- spring has the function of adding return force to the swing link mechanism and the function of accumulating and releasing the operating force during the sale, and also prevents changes in the return force depending on the degree of deformation of the swing link mechanism. It is an object of the present invention to provide a bicycle derailleur which can be made as small as possible and has a simplified mechanism by reducing the number of parts.

[Means to solve the problem]

In order to solve the second problem, the present invention takes the following technical measures. A base member, a parallel first link and a second link pin-coupled to the base member so that one end thereof can swing, and a movable member whose other ends of the first link and the second link are pin-coupled so that they can swing relative to each other. A bicycle derailleur comprising a swing link mechanism and a chain guide member attached to a movable member of the swing link mechanism, the bicycle derailleur including a spring that moves the first link and the second link closer to or apart from each other. is provided, and one of the connecting portions to the base member or movable member indicated by - at both ends of the first link or the second link slides on a pin fixed to the base member or movable member side. guide you,
It also has an arcuate elongated hole centered around the pin of the other end side coupling portion, and an operating cable is connected to the link in which this elongated hole is formed.

[Effect]

Now, since it is in a cylinder, it is assumed that a spring is provided that urges the first link and the second link to approach each other, and that the joint between the second link and the movable member is fixed to the movable member. and a long hole provided in the second link so as to slide and guide the pin, and centered on the center of swing of the second link with respect to the base member, that is, the pin connecting the second link and the base member. It is assumed that it consists of Then, an operating cable connected to the speed change lever is fixed to this second link. In this type of swing link mechanism, pins 411111, which are pins that connect the base part 1 and the first and second links, and pins that connect these links and the movable part +4, connect each vertex of a parallelogram. Therefore, when an external force is applied to this swing link mechanism, the movable member moves in parallel in an arc centered on each pin connecting the base member and the first and second links. At this time, the distance between the opposite sides of the parallelogram changes, so
The swing link mechanism of the present invention, in which a spring is provided so as to reduce the distance between the first link and the second link constituting the opposite side, can be operated in one direction, that is, the distance between the first link and the second link is It will always be elastically biased in the direction of shrinkage. The second link and the movable member are constructed by sliding and holding a pin on the movable member side in an arc-shaped elongated hole provided in the second link. While maintaining the state of the link and movable member, it is possible to relative swing around the connecting pin on the base member side within the range ffff allowed by the elongated hole, but in the 1ffi rich state, as described above, the - Since a spring is provided that brings the link and the second link closer to each other, the second link takes a state closest to the first link as far as the slotted hole allows. As mentioned above, when the operation cable is pulled and the second link is rotated from the normal state where the first link and the second link are closest to each other, the intervening link is inserted between the second link and the first link. The first link also rotates in the same direction as it is pulled by the second spring. Therefore, the swing link mechanism is deformed, the movable member and the chain guide member attached to it move in parallel, and the chain guide member attached to the movable member moves in parallel.
can be replaced by IJI. Due to the deformation of the swinging link at this time, the distance between the first link and the second link that constitute the opposite sides of the parallelogram increases, so that the above spring stores an I-1 loading force, and therefore this swinging link An elastic return force is applied to the mechanism. Conversely, when the pulling force of the operating cable is released, the swing link mechanism returns to deformation due to the above-mentioned elastic return force. Therefore, the swing link mechanism can be reciprocated by pulling and releasing the operating cable, and the chain guide member attached to the convex moving part can be moved in parallel in the width direction of the multi-stage sprocket. As a result, the J change is performed in 11) of Che7. On the other hand, as mentioned above, it is possible for the second link to swing relative to the connecting pin on the base member side within the range permitted by the hole while maintaining the state of the first link and the movable member. Even if movement of the movable member is locked while the bicycle is stopped, the second link can be swung by pulling the operating cable. In this case, since the second link is separated from the first link, the spring interposed between them is energized. Then, when the bicycle starts moving and the lock on the movable member is released, the first link swings toward the already rotated second link due to the stored force of the spring. Accordingly, the movable member also moves in parallel. At this time, the pin connecting the movable member and the second link slides in the arc-shaped long hole provided in the second link, but as mentioned earlier, this long hole is connected to the second link. Since it has an arc shape centered on the pin that connects the link and the base member, the four pins that connect each part 10A of the swing link mechanism still form the vertices of the parallelogram, Therefore, the movable member moves in parallel. In this way, even when the movable member is locked by check 7 during stoppage, the operating force is temporarily stored by operating the gear shift lever, and after the bicycle is started, this stored force can be used to move the bicycle to one target. A so-called safety function, which allows the driver to perform a speed change operation, is also achieved.

【effect】

As described above, according to the present invention, the return force of the swing link mechanism can be obtained with a single spring, and the saver function can also be performed. In addition, since the first link or the second link is also used as an operating member to perform the saver function, the number of parts is reduced while providing the saver function, simplifying the mechanism, and significantly reducing the need for derailleurs. It becomes possible to make it more compact. Furthermore, since the spring that elastically biases the swing link mechanism in one direction is provided to reduce or expand the distance between the first link and the second link, The amount of deformation of the spring can be made smaller than in the past, which reduces the difference in return force between the initial stage of deformation and the final stage of deformation of the swing link mechanism. As a result, the operating force required to resist this return force can be reduced, allowing for nimble gear shifting operations.

[Explanation of Examples]

Embodiments of the present invention will be specifically described below with reference to the drawings. Note that the drawings illustrate the present invention as a bicycle rear derailleur,
That is, the selected one of the multi-stage freewheels
An example is shown in which this is applied to a derailleur configured to change the load. As shown in FIG. 1, the derailleur 1 of this example is particularly configured so that it can be installed on a bicycle equipped with a bicycle stand 2, such as a women's bicycle or a utility vehicle. The derailleur 1 basically includes a base part 3 attached to the vehicle body frame, and a parallel first link 7 and a second link 8 which are swingably connected to the base member 3 at one end. These first and second links 7,
The chain guide member 11 is attached to the movable member 9, and the chain guide member 11 is attached to the movable member 9. The posture of the swing link mechanism 10 is set such that when the swing link mechanism 10 is deformed, the movable member 9 moves in parallel in the width direction of the bicycle, that is, in the case of a rear derailleur, in the width direction of the multi-stage freewheel F. In this example, the base member 3 is fastened together with the bracket 6 of the stand 2 to the end of the hub axle 5 fixedly supported by the fork end 4, and the base member 3 is attached from the part to the stand 2.
It has a shape that extends forward and hangs downward at the rear to avoid the problem. The lower end portions of the first link 7 and the second link 8 are swingably connected to the base member 3 via pins 12 and 13 that are supported inside the lower end of the base member 3 so as to be spaced apart from each other. And the first link 7 and the second link 8
A movable member 9 is connected to the upper end of each via a pin 14, 15. Pins 12, 13.14 connecting the base member 3, each link 7.8 and the movable member 9 to each other
15 forms the vertex of the parallelogram. Therefore, when the swing link mechanism 10 swings in and out with respect to the base member 3, the movable member 9 moves along the length of the link 738 with the pin 12 or 13 as the center. It will move in parallel in the inward and outward directions while drawing an arc-shaped locus with a radius of . In the case of a rear derailleur, the chain guide member 11 consists of a frame 18 that supports a guide pulley 6 at the top and a tension pulley 17 at the bottom, as shown in FIGS. 1 and 2. A tension pulley 17 is supported by the movable member 9 so as to be able to swing around a support shaft 19 parallel to the hub shaft 5 while being always given elasticity to move backward. After the check 7C has been rotated by hooking the rear side of the tension pulley 17 and the front side of the guide boot I716, it is attached to one sprocket 5l-s of the freewheel F.
3 gets turned around by t++. Since the hook replacement frame 18 is biased as described above, even if the chain 7C is replaced with a sprocket of a different diameter on the freewheel F and the amount of slack changes, the tension pulley 17 will elastically move backward. , this slack is removed, and appropriate tension is constantly applied to chain C. Now, the present invention provides a method of arranging a spring so as to return and deform the swing link mechanism 10 made up of the base member 3, the first link 7, the second link 8, and the movable member 9 in one direction, and It is characterized by a structure that allows this spring to store operating force during so-called saver mode. First, the swing link mechanism 10 is biased by a spring 20 that is attached to move the first link 7 and the second link 8 closer to each other or to move them apart. A spring is attached to keep the link 7 and the second link 8 close to each other at all times. That is, the coil portion of the torsion spring 20 is inserted into the pin 13 that connects the base member 3 and the second link 8, and the both ends 20a and 20b are connected to the first link 7 while the coil portion is given an initial aperture. These are latched from the outside to latching portions 21 and 22 formed on the second link 8, respectively. As a result, the swing link mechanism 10 moves in the direction in which the first link 7 and the second link 8 approach each other, that is, each pin 12, 13,
The parallelogram having vertices 14 and 15 is elastically biased so that it is obliquely collapsed. Next, in order to cause the spring 20 to perform an energy storage function during the saver mode, the connecting portion between the second link 8 and the movable member 9 is configured as follows. That is, the second link 8
A pin 15 that connects the movable member 9 to the movable member is fixed to the movable member, and a hole 23 on the second link side through which the pin 15 is inserted is inserted.
is formed into an elongated hole shape with the center of swing of the second link 8 relative to the base member 3, that is, the pin 13 as the center. As a result, in the normal state, the first link 7 and the second link 8 are urged in the proximal direction by the spring 20 as described above, so the pin 15 in the elongated hole 23 is inserted into the elongated hole 23. It is stabilized by abutting on the opposite end 23a, but when the movable member 9 is locked, only the second link 8
It is possible to swing in the direction of arrow T while tightening the spring 20. During this time, the pins 12, 13, 14, 15 still form the vertices of the parallelogram, so the posture of the movable member 9 or chain guide member 11 does not change.
A cable fastening portion 24 extending downward is formed on the second link 8, and an operating force from a cable W connected to the speed change lever at one end is input thereto. In this example, a double cable is used in which the inner cable W2 is inserted into the outer cable Wl, and the receiver extends from the outer cable W1 which is stopped by the outer cable receiver 25 provided in the continuous part of the base member 3. An end portion of the inner cable W2 is connected to this cable fastening portion 24. In the illustrated example, this fastening part 24 is configured to connect the cable ends along the arc-shaped reel part 26 centered on the pin 13, so that the inner cable W
This eliminates the vibration of the inner cable w2 when the second link 8 is rotated by pulling the cable W2, and the second link 8 can be rotated in proportion to the amount of pulling of the cable W2. Next, the operation of this embodiment will be explained. When the gear shift lever is operated from the state shown in FIG. 2 to pull the inner cable w2 in the P direction and swing the second link 8 in the direction of the arrow I, the pin 15 is pushed into the elongated hole by the elasticity of the spring 20. The first link 7 remains in contact with the inner end 23a of 23.
The link mechanism 10 also swings in the direction of arrow I7, and the swing link mechanism 10 as a whole is deformed to the state shown in the Nth position. As a result, the movable member 9 or the chain guide member 11 are also moved in parallel in the direction of the arrow I7, and the chain C is rerouted to the large diameter sprocket S3 side. At this time, since the distance between the first link 7 and the second link 8 increases, additional elasticity is stored in the spring 20, and the swing link mechanism IO attempts to return elastically in the direction of the arrow T. The speed change lever is provided with a frictional resistance capable of resisting this return force, so that the swing link mechanism 10 is held in the deformed state as shown in FIG. 4. On the other hand, when the gear shift lever is operated in the opposite direction as shown in FIG. The two links 8 swing back in the direction of arrow T, and the swing link mechanism 10 returns to the state shown in FIG. Also in this process, the first link 7 and the second link 8 are urged in the direction of approaching each other, so the pin 15 contacts the inner end 23a of the elongated hole 23 of the second link 8. The current state will be maintained. As a result, the movable member 9 or the chain guide member 11 moves back in the direction of the arrow T, and the chain C is replaced by the small diameter sprocket 5llffll. Furthermore, the upper end of the second link 8 is connected to the movable member 9 by slidingly guiding a pin 15 fixed to the movable member 9 side through an arc-shaped elongated hole 23 centered on the pin 13 at the base end thereof. Therefore, even when the movement of the movable member 9 is locked, such as when the bicycle is stopped, the cable W2 can be pulled in the direction of the arrow P, as shown in FIG. 5, and only the second link 8 can be moved in the direction of the arrow. It can be swung. At this time, since the second link 8 expands relative to the first link 7, additional elasticity is stored in the spring 20. Then, when the bicycle starts moving and the lock on the movable member 9 is released,
Due to the above-mentioned additional elasticity, the first link 7 is swung in the direction of arrow I so as to follow the second link 8, resulting in the state shown in FIG. 4. Therefore, a so-called 7-6 function is achieved in which the operating force is temporarily stored in the spring 20 while the bicycle is stopped, and the movable member 9 is moved to perform a speed change operation after the bicycle is started. Of course, the scope of the invention is not limited to the embodiments described above. First, in the embodiment, the elongated hole 23 of the second link 8 is formed at the joint part with the movable member 9, and the second link 8 is connected to the other swing link constituent members around the joint part with the base member. The first link 7 is configured to swing relative to the base member 3, but a long arc-shaped hole is provided at the lower end of the first link 7 with the pin 15 at the upper end as the center, and the pin 12 fixed to the base member 3 side is slid into this hole. Even if the first link 7 is dynamically fitted and an operating force is input to the first link 7, the same function as in the illustrated example can be achieved. Further, in the embodiment, the spring 20 is attached so that the first link and the second link are brought close to each other, but on the contrary,
A spring can also be installed to separate the first link and the second link from each other. In this case, the normal state is a state in which the distance between the first link and the second link is widest, that is, a state in which the movable member has moved toward the large diameter sprocket S3. In this case, when inputting the operating force to the second link,
An arc-shaped length that slides and fits with the pin 15 of the movable member so that additional elasticity is stored in the spring when only the second link is swung toward the small-diameter sprocket, that is, toward the top when the movable member is locked. All you have to do is form a hole. In addition, when inputting operating force to the first link, a long arc-shaped hole centered on the pin at the top end is provided at the bottom end of the first link, and this hole is slidably fitted into the pin fixed to the base member side. It's a good thing. Furthermore, in the illustrated example, both ends of a torsion spring inserted into the pin 13 are hung between the first link 7 and the second link 8 as a spring that urges the first link 7 and the second link 8 to approach each other. However, there is no problem with how this spring is arranged. However, if a torsion spring is used, it is advantageous for its coil portion to be inserted into a pin 13 or pin 14 forming an acute angle of a parallelogram. Furthermore, a front derailleur is constructed by fixing the base member to a sheet pipe near the multi-stage chain wheel, and attaching a chain guide member, which consists of a pair of inner and outer guide plates that sandwich the chain that is about to be hung on the chain wheel, to the movable member.

[Brief explanation of the drawing]

FIG. 1 is an overall side view of one embodiment of the present invention, and FIG.
3 is a view taken along the line m-m in FIG. 2, and FIGS. 4 and 5 are taken along the n-r+ line in FIG. It is a figure corresponding to an arrow view view. l... Derailleur, 3... Base member, 7... First link, 8... Second link, 9... Movable member, 1
0... Swinging link mechanism, 11... Chain guide member,
20...Spring, 23...Elongated hole, W...Cable.

Claims (1)

[Claims] (1) a base member, a parallel first link and a second link pivotally connected to the base member with a pin at one end;
and a swinging link mechanism including a movable member to which the other ends of the first link and the second link are pin-coupled so as to be able to swing relative to each other, and a chain guide member attached to the movable member of the swinging link mechanism. The bicycle derailleur is provided with a spring for moving the first link and the second link closer to each other or separating them from each other, and a connecting portion of both ends of the first link or the second link to the base member or the movable member. One of them is composed of a pin fixed to the base member or the movable member, and an arc-shaped elongated hole that slides and guides this pin and has the pin at the other end connecting part as its center, and , a bicycle derailleur characterized in that an operation cable is connected to the link in which the elongated hole is formed.