JPS643654Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a jig for disassembling and assembling a freewheel.
Alternatively, the present invention relates to a jig for disassembling and assembling a freewheel, which is configured to extremely easily screw a screw lid onto or remove it from a core while adjusting the screw lid to the core.

In a freewheel, particularly a multi-stage freewheel, as shown in FIG. 6, a sprocket support b having a plurality of sprockets a of different diameters is rotatably supported in only one direction relative to a core c.
In this, the plurality of different diameter sprockets a
...is done by sequentially fitting several large-diameter sprockets into the large-diameter portion d of the sprocket support b with a spacer e in between, and then sequentially screwing several small-diameter sprockets into the threaded portion of the small-diameter portion f. Attached to sprocket support. Further, the sprocket support b has a space between the ball receiving surface g formed on the inner circumferential portion at the inner end thereof and the ball receiving surface h formed on the outer circumferential surface at the inner end of the core c, and A steel ball that can roll between a ball receiving surface i formed on the inner circumferential surface at the outer end and a ball receiving surface k of a screw lid j screwed to the threaded portion of the outer part of the core c. By interposing the groups m and n, and incorporating a freewheel clutch, that is, a one-way clutch generally consisting of a ratchet mechanism o, between the outer periphery of the middle part of the core c and the inner periphery of the middle part of the sprocket support b. , are attached to the core c. The freewheel configured in this way can be assembled to the hub by screwing the threaded part p on the inner periphery of the inner part of the core c to the threaded part (not shown) of the barreled part of the hub (not shown). Can be attached.

The screwing amount of the screw cap j is adjusted, the force with which the ball receiving surfaces g, h, i, and k sandwich the steel ball groups m and n is adjusted, and the rotation condition of the sprocket support relative to the core c is adjusted. There are generally two types of means for adjusting this. The first is, as shown in FIG. The screw cover j is fixed at a proper screwed-in position by screwing the screw cover j and the locking ring q together as a double nut. A plurality of thin plate-shaped tension plates (not shown) are stacked and interposed between the stepped wall r adjacent to the threaded portion p and the screw lid j, and the sprocket is supported by adjusting the number of the tension plates. This is to match the rotation of body b.

By the way, when removing sprocket a...
This sprocket a... is strongly screwed into the threaded part f of the sprocket support body b due to the chain driving force during installation and use, so a considerable amount of force is required to remove it. The work is very cumbersome because it needs to be firmly fixed to something. Also, when adjusting the screwing amount of the screw cap j, especially when the screw cap j and the lock ring q act as a double nut like the one in Fig. 6, the screw cap j must be adjusted to the appropriate amount. Once screwed in, it is necessary to hold the lock ring q in that position and then screw the lock ring q in that position, which is very difficult and requires considerable skill.
Needless to say, it is very troublesome to remove the screw cover j and lock ring q that have been screwed in this way.

An object of the present invention is to provide a new jig that can extremely easily carry out the operations for disassembling, assembling, and adjusting the freewheel as described above.

In order to achieve this purpose, the present invention takes the following technical measures. That is, a first jig is provided, which has a freewheel holding means for holding the freewheel in a fixed state, and a locking means for preventing the sprocket of the freewheel from rotating; and,
A connecting means for detachably connecting to the first jig; and a screw lid rotating means for engaging with and rotating the engaging portion of the screw lid of the freewheel; In addition, a second lock ring rotating means is provided which engages with and rotates the engaging portion of the lock ring of the freewheel.
This is because a jig was installed.

In this way, the first jig holds the freewheel with its core fixed, and the hooking means is hooked to one of the plurality of sprockets, preferably having a large diameter, so that the freewheel is secured to the core. A plurality of sprockets can be removed from the sprocket support by preventing the sprocket support from rotating and then using a suitable sprocket turning tool to unscrew the sprockets in sequence starting with the smallest diameter sprocket. Further, in the same way as above, the freewheel is held in the first jig, and a hooking means is hooked on the first sprocket to prevent the sprocket support from rotating with respect to the core, and the second jig is held in the freewheel. is connected to the first jig, and the screw lid rotation means and lock ring rotation means of the second jig act on the screw lid and lock ring, respectively, thereby making it extremely easy to tighten, adjust and remove these screw lids and lock rings. It can be carried out.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view of a state in which the first jig and the second jig are connected. Moreover, FIG. 2 is an overall perspective view showing the appearance of only the first jig. As is clear from the figure, the first jig 1 in this embodiment includes a freewheel holding means 2 for holding the freewheel by tightening the screw hole p of the freewheel core c, and a freewheel holding means 2 for holding the freewheel by tightening the screw hole p of the freewheel core c. It has a locking means 3 for locking the sprockets a to prevent the sprocket support b from rotating relative to the core c. The freewheel holding means 2, as shown in FIG. 2, has an outer shaft 4 and an inner shaft 5 which are screwed into each other at the base. The base end of the inner shaft 5 is a square shaft portion 6
is formed, and by holding it in a vise, for example, the entire jig of the present invention can be fixed. On the other hand, the upper end of the inner shaft 5 is formed with a cone outer surface 7 whose diameter decreases toward the top, and is joined to the cone inner surface 8 formed on the upper inner periphery of the outer shaft 4 in a sliding manner. The outer shaft 4 is also provided with a plurality of axial slits 9 up to its upper end, and when the outer shaft 4 is rotated relative to the inner shaft 5 and moved downward, the above-mentioned cone inner surface 8 and cone outer surface are formed. Due to the action of 7, its upper part expands in diameter so that it can tighten the screw hole p of the freewheel core c. The outer diameter of the upper end shaft portion 10 of the outer shaft 4 is therefore approximately equal to the inner diameter of the screw hole p of the freewheel core c. Furthermore, a large-diameter portion 11 is provided at the lower portion of the outer shaft 4, and a pair of handles 12 extending laterally from the large-diameter portion 11 are attached. The handle 12 rotates the outer shaft 4 with respect to the inner shaft 5 to hold the freewheel. As clearly shown in FIG. 1, the large diameter portion 11 has a flat surface 13 formed thereon.
By holding the freewheel and then changing the vise to this flat part 13, the outer shaft 4 can be inadvertently
This prevents the freewheel from rotating in the opposite direction with respect to the inner shaft 5 and reducing the tension force for holding the freewheel.

The outer shaft 4 also has a horizontal plate 14 on which a freewheel is placed, and a flange 15 and a step 16 are formed in the upper part of the outer shaft 4. 16 and place it on the flange 15,
The plate 14 is attached by screwing a countersunk screw 19 through the screw hole 18 of the plate 14 to the flange 15. Since the outer shaft 4 is expanded in diameter, the inner diameter of the central hole 17 is set to be slightly longer than the outer diameter of the stepped portion 16, and the diameter of the screw hole is also set to be larger than necessary.

The stopper means 3 for preventing the sprocket support b from rotating relative to the core c is attached to an appropriate portion of the plate 14. In the illustrated example, a bicycle drive chain 3 is used as the stopper means 3. One end of the chain 3 is fixed to a block-shaped fixture 20 provided at an appropriate portion of the plate 14, and the other end is open. A pair of chains 3 are provided. This is to prevent the sprockets a... supported by the sprocket support b from rotating both clockwise and counterclockwise.

As mentioned above, the first jig 1 configured as above can be used mainly for attaching or detaching the sprocket a to the sprocket support b, and its usage is as follows. It is.

First, attach the freewheel to the screw hole p in the core c.
the freewheel holding means 2, i.e. the outer shaft 4
The plate 14 is fitted onto the upper end shaft portion 10 of the plate 14.
and turn the handle 12 to fix the core c to the freewheel holding means. Next, when attaching the sprockets a to the sprocket support b, the large diameter sprocket and the small diameter sprocket are sequentially screwed into the large diameter part d and the small diameter threaded part f of the sprocket support b, and at this time, as shown in FIG. As shown, the chain 3, which is the hooking means, is hooked onto one of the large diameter sprockets, and in this state, the smallest diameter sprocket is screwed into the small diameter screw of the sprocket support b using the sprocket turning tool 21. Tightly screw into part f. The large-diameter sprocket on which the chain 3 is hooked is fitted into the large-diameter portion d of the sprocket support b in a spline shape, so that it does not rotate relative to the sprocket support b. Therefore, the reaction force when the smallest diameter sprocket is strongly screwed in as described above is effectively transmitted to the chain 3, which is the locking means.

Fig. 4 shows a sprocket turning tool 21 for screwing the smallest diameter sprocket as described above.
An example is shown below. This sprocket turning tool 21
A pair of pins 23 are provided on the main body 22, a pair of pins 25 are provided on a slide block 24 slidably assembled to the main body 22, and a pair of handles 26 extend from the main body 22 in opposite directions.
It is configured by installing. The two pairs of pins 23 and 25 engage with teeth located diametrically opposed to each other on the sprocket so as to sandwich them therebetween. In this state, if the tool is rotated by applying force to the handle 26, even a tightly tightened sprocket can be removed very easily. Note that one of the two sets of pins is attached to the slide block because
This is to allow this tool to be used with sprockets having various numbers of teeth.

FIG. 5 is an overall external view showing the external appearance of the second jig 27. As shown in FIG. In this embodiment, this second jig 27
are the screw lid rotation means 28 and the lock ring rotation means 2.
9. This second jig 27 has a central axis 30 as shown in cross section in FIG.
, an intermediate shaft 31 that is fitted on the outside of this and can be rotated independently, and an outer shaft 32 that is fitted on the outside of this and can be rotated independently.

The first jig 1 is attached to the lower end of the center shaft 31.
A screw shaft 33 is formed as a connecting means for removably connecting the second jig 27, and this screw is inserted into an axial screw hole 34 bored at the upper end of the inner shaft 5 of the first jig 1. It is designed so that it can be screwed together.

The screw lid rotating means 28 includes the outer shaft 32, a screw lid engaging portion 35 provided at the lower end of the outer shaft 32, and a handle 36 attached to the outer shaft 32 and extending in the transverse direction. The engaging portion 35 is for engaging an appropriate portion of the screw lid j to rotate it, and the illustrated example is an engaging portion that can engage with an engaging recess s formed in the screw lid j. This is in the form of a mating convex portion 35. As shown in FIG. 1, this engaging protrusion 35 can be replaced even if it is damaged by fitting a separately formed hard pin into the slot on the inner surface of the outer shaft 32. This is convenient because it allows you to

The lock ring rotation means 29 is composed of the intermediate shaft 31, a lock ring engaging portion 37 provided at the lower end of the intermediate shaft 31, and a handle 38 extending in the transverse direction attached to the upper end of the intermediate shaft 31. The engaging portion 37 is for engaging an appropriate portion of the lock ring q and rotating it. This is the aspect of the department. Similarly to the screw lid engaging part 35, this lock ring engaging part 37 is preferably made by fitting a separately formed hard pin into a slot on the outer surface of the intermediate shaft 31.

The second jig configured as described above screws the screw lid and lock ring onto or removes them from the threaded portion of the outer end of the freewheel core, and further screws the screw lid and lock ring into a so-called double nut shape. It is used for tightening, and its usage is as follows.

First, with the first jig 1 supporting the freewheel, the second jig 27 is rotated by manipulating the handlebar 39 to rotate the screw shaft 33, which is the connecting means, and the inside of the first jig 1 is rotated. It is screwed into the axial screw hole 34 of the shaft 5 and connected to the first jig. In this state, when the handle 36 is operated to rotate the outer shaft, since the outer shaft 32 is elastically biased downward by the spring 40, the threaded lid engaging portion 37 at the lower end is rotated. It automatically engages into the engagement recess s formed on the end surface of j. Also, handle 3
8 to rotate the intermediate shaft 31, the intermediate shaft is elastically biased downward by the spring 41, so that the lock ring engaging portion 37 at the lower end of the intermediate shaft rotates.
automatically engages into the engagement recess t on the end face of the lock ring. Therefore, in this state, by operating the handle 36 or the handle 38 separately, the screw cap j and the lock ring q can be independently screwed onto the small diameter screw portion of the core c.

To adjust the rotational condition of the sprocket support b relative to the core c, operate the handle 36 while checking the rotational condition of the sprocket support b to screw the screw cover j by the desired amount, and then turn the handle 36.
remain in position, then turn the handle 38
The long ring q can be tightened into a double nut shape against the outer surface of the screw cover j by operating the . Further, in order to remove the lock ring q and the screw cover j, rotate the handle 38 and the handle 36 in the opposite direction to the above and remove the lock ring q and the screw cover j.
You can remove them in this order.

FIG. 7 shows another embodiment of the first jig of the freewheel disassembly and assembly jig of the present invention.

The first jig of this embodiment has a flat part 42 at the lower part for clamping with a vise, a cylindrical body part 43 for fitting the screw hole p of the core c at the upper part, and a cylindrical body part 43 at the upper end, which will be described later. A shaft-shaped jig main body 47, each having a square shaft portion 45 for fitting an attachment 44, and an axial screw hole 46 for screwing a screw shaft 33, which is a connecting member of the second jig 27, on its upper end surface, and The core c fitted into the cylinder body 43 is the jig main body 47.
It consists of a combination of attachments 44 to prevent rotation relative to the Attachment 4
4 has an outer diameter that is approximately the same as the outer diameter of the small-diameter screw portion at the outer end of the core c, and a square hole 48 in the lower part that can accommodate the square shaft portion 45 of the jig main body 47 in a non-rotatable manner. and,
It has an engagement protrusion 49 that can engage with an engagement groove u formed at the outer end of the core c. The jig main body 47
After fitting the screw hole p of the core c of the freewheel into the cylindrical shaft portion 43 of When attached so that they fit into each other, the core c is supported non-rotatably with respect to the jig main body 47.

Using the first jig of this example, sprocket a
The procedure for attaching or removing the... to the sprocket support b is the same as when using the first jig shown in FIGS. 1 to 3.

It goes without saying that the scope of the invention is not limited to the embodiments shown in the figures.

That is, as the freewheel holding means of the first jig 1, the freewheel core c
Any structure may be used as long as it can non-rotatably support it.

In addition, the second jig may be adapted to a freewheel in which the screw cover j and lock ring q are tightened together in a double nut shape as shown in the illustrated example, or a conventional tone plate made of a plurality of laminated plates. It can also be adapted to a freewheel type in which only the screw cover is screwed through. In this case, the structure is such that the lock ring rotation means 29, that is, the handlebar 39, the spring 41, and the intermediate shaft 31 are omitted from the second jig shown in FIG.
The shape of the screw lid engaging portion 35 of the screw lid rotating means 28 may be adapted to the shape of the engaging recess formed on the outer end surface of a normal screw lid.

Further, in the illustrated example, the first jig is configured to be held in a vice, but the method of fixing the jig is not limited to this, and various conventionally used methods may be used. Bye.

As explained above, the freewheel disassembly and assembly jig according to the present invention is capable of attaching or removing a plurality of sprockets to a sprocket support, screwing or removing a screw cover or lock nut, and furthermore, This has the unique effect that comprehensive maintenance of the freewheel, such as adjusting the rotational condition of the support relative to the core, can be performed very easily.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing the first jig and the second jig connected and the freewheel attached;
3 is an explanatory diagram of how to use the first jig, FIG. 4 is a perspective view showing an example of a freewheel rotation tool, and FIG. 5 is a perspective view of the second jig. FIG. 6 is a perspective view of the entire jig, FIG. 6 is a sectional view of the freewheel, and FIG. 7 is a sectional view showing another embodiment of the first jig. DESCRIPTION OF SYMBOLS 1... First jig, 2... Freewheel holding means, 3... Stopping means, 27... Second jig, 2
9... Lock ring rotation means, 33... Connection means, a... Sprocket, c... Core, j... Screw lid, q... Lock ring, s... Screw lid engaging portion, t... Lock ring engagement. Joint section.

Claims (1)

[Scope of utility model registration request] a first jig having a freewheel holding means configured to hold the core of the freewheel in a fixed manner and a locking means configured to prevent the sprocket of the freewheel from rotating; and the first jig. a screw lid rotating means that engages with and rotates the engaging portion of the screw lid of the freewheel;
Alternatively, in addition to this, a second jig includes lock ring rotating means that engages with and rotates the engaging portion of the lock ring of the freewheel;
A jig for disassembling and assembling a freewheel, characterized by being provided with.