JPS6036540Y2 - sprocket assembly - Google Patents

Description

[Detailed description of the invention] The present invention is a sprocket assembly, specifically, a cylindrical member,
The present invention relates to a sprocket assembly including a plurality of sprockets coupled to the outer periphery of the cylindrical member.

Usually, in this kind of assembly, the sprocket is connected to the cylindrical member by providing a screw on the outer periphery of one axial end of the cylindrical member, and a plurality of spline grooves along the axial direction on the outer periphery of the other end. A sprocket having a plurality of protrusions that fit into the spline grooves on the inner periphery of the center hole is fitted sequentially at regular intervals from the largest diameter sprocket through spacers, and An internal thread is provided on the periphery, and the sprocket is connected to the thread of the cylindrical member by screwing it.

Therefore, with the coupling structure configured as described above, there is a problem in that coupling and detaching the sprocket to the cylindrical member is troublesome, and furthermore, the sprocket is screwed in the direction that is tightened during forward rotation, so that the sprocket does not tighten easily. Since the sprocket is designed to prevent it from loosening easily, when driving torque is transmitted from the chino attached to the sprocket, the threaded sprocket tightens, making removal extremely difficult.

However, when the sprocket connected to the cylindrical member is hung as described above and the sprocket is replaced with one of the sprockets to change the speed, there is a problem that the sprocket falls off to the side of the smallest diameter sprocket. There is.

Conventionally, a disk-shaped protector having an outer diameter larger than the outer diameter of the smallest diameter sprocket is screwed onto the outer side of the smallest diameter sprocket in the cylindrical member to prevent the chain from falling off. has been proposed.

However, the protector screwed onto the cylindrical member as described above has
Since the driving torque of the chino attached to the sprocket does not act at all, there is a problem in that the protector is very likely to loosen during use.

The present invention was devised in view of the above-mentioned problems, and its purpose is to make it easy to connect and remove sprockets and protectors from the cylindrical member, and to easily do so without using any special tools. Another object of the present invention is to provide a sprocket assembly that can reliably prevent the protector from loosening.

Therefore, the present invention provides a plurality of spline grooves on the outer periphery of a cylindrical member, a screw on the outer periphery of one end in the axial direction, and a plurality of sprockets with different diameters on the outer periphery of the cylindrical member. The sprocket assembly is a sprocket assembly in which a disc-shaped protector having an outer diameter larger than the outer diameter of the smallest diameter sprocket is formed, and a cylindrical host with an internal thread provided at the center of the protector. The boss is screwed onto the screw to fix the axial movement of the sprocket, and the boss is formed with at least one through hole and projects inward at one end. A C-shaped retaining ring formed from a bullet having a hook is formed, and the hook of the retaining ring passes through the through hole and engages with one of the spline grooves of the cylindrical member. That is.

Embodiments of the assembly of the present invention will be described below with reference to the drawings.

In the figure, 1 is a cylindrical member constituting a driving member in a multi-stage freewheel, and 2... is a sprocket connected to the outer periphery of the cylindrical member 1. A plurality of spline grooves 11 are provided along the axial direction and open outward at one end in the axial direction, and a screw 12 is provided on the outer periphery of the one end in the axial direction. A ratchet 13 that engages with the pawl of the driven member and ball races 14 and 15 provided on both sides of the ratchet 13 in the axial direction are provided.

The sprockets 2 have different outer diameters, have a large number of teeth with different numbers of teeth on the outer periphery, and have protrusions 21 protruding from the inner periphery that can be inserted into the spline grooves 11. are doing.

These sprockets 2 are held at regular intervals via annular spacers 3, and are joined together by connector stages 4 such as bolts/nuts or caulking pins to form a sprocket assembly A.

Then, this sprocket assembly A is inserted onto the outer periphery of the cylindrical member 1 and fixed by a protector 5 that is screwed into the screw 12 of the cylindrical member 1.

Therefore, this protector 5 is connected to the sprocket 2.
A cylindrical boss 52 formed in a disk shape having an outer diameter larger than the outer diameter of the smallest diameter sprocket 2a in..., and provided with an internal thread 51 corresponding to the screw 12 in the center of the protector 2. 7. Screw the internal thread 51 of this boss 52 onto the screw 12 to bring one end of the boss 52 into contact with the outer surface of the minimum diameter sprocket 2a, and move the sprocket assembly A in the axial direction. The boss 52 is formed with at least one through hole 53 passing through in the diameter direction, and one end of the C-shaped retaining ring 6 is fitted into the through hole 53. be.

This retaining ring 6 is formed of a bullet wire and is held on the outer periphery of the boss 52 by its elastic restoring force, and a hook 62 that projects inward is provided at one end of the retaining ring 6.
A knob 62 protruding outward is provided at the other end, the hook 61 of the retaining ring 6 is inserted into the through hole 53 provided in the boss 52, and the tip of the hook 61 is inserted into the tubular member 1. It is engaged with one of the spline grooves 11 to prevent the protector 5 from loosening.

Incidentally, the through hole 53 provided in the boss of the protector 5 is
When the wire diameter of the retaining ring 6 is 1 m/m, the pitch of the spline grooves 11 provided on the outer periphery of the cylindrical member 1 is equal to the pitch of the through holes 53 and the two-sided through holes 53. Although two through holes 53 are provided, the diameter and number of through holes 53 are not particularly limited.

In addition, 7 in the figure indicates the minimum diameter sprocket 2a and the boss 5.
This is a spacer interposed between 2 and 2.

In the above configuration, the sprocket assembly A fitted onto the outer periphery of the cylindrical member 1 is prevented from moving in the circumferential direction by the engagement of the protrusion 21 provided on each sprocket 2 with the spline groove 11, and the protector Boss 52 in 5
is prevented from moving in the axial direction by the engagement I'L with the internal thread 53, and is immovably attached to the cylindrical member 1 without moving in the circumferential and axial directions, and the hook 61 of the retaining ring 6 is a through hole 53 provided in the boss of the protector.
By penetrating through and engaging one of the spline grooves 11, it is possible to prevent the protector 5 screwed onto the screw 12 from rotating in the direction of loosening, and also prevent the protector 5 from rotating the axis of the sprocket assembly A. By preventing movement in this direction, the protector 5 is prevented from rotating in the tightening direction, and can be attached to the cylindrical member 1 without loosening.

Further, the sprocket assembly A and the protector 5 connected to the cylindrical member 1 as described above are attached to the hook 61 of the retaining ring 6.
By pulling it out from the through hole 53 and disengaging it from the spline groove 11, it can be easily removed from the cylindrical member 1.

That is, the protector 5 screwed onto the screw 12 of the cylindrical member 1
Since the driving torque of the chain hooked on the sprocket 2 of the sprocket assembly A does not act at all, the hook 61 is not tightened during use, and the hook 61 is not loosened due to its engagement with the spline groove 11. Since the protector 5 is prevented from moving in the axial direction of the sprocket assembly A by tightening the screw 12 loosely without firmly tightening it, the protector 5 can be loosened with a small force. The sprocket assembly A can be rotated and easily removed, and the sprocket assembly A can be easily removed by pulling the sprocket assembly A in the axial direction with respect to the cylindrical member 1.

In the above explanation, the sprockets 2... are connected by the main connecting stage 4, but each sprocket 2 is inserted independently without using the connecting means 4, and the spacer 3 is used to maintain a constant distance. It may also be assembled.

The cylindrical member 1 has a straight outer periphery and is provided with the spline groove 11 as shown in FIG. When using a general cylindrical member in which the outer periphery on the other end side has a large diameter and a step 18 is provided between the small diameter part 16 and the large diameter part 17, the small diameter part 16 and the large diameter part 11 have the above-mentioned diameter. The spline groove 11 is provided, and the screw 12 is provided on the outer periphery of the small diameter portion 16 on one end in the axial direction.

As described above, the assembly of the present invention has multiple sprockets,
A cylindrical boss is connected to the outer periphery of a cylindrical member having a thread on the outer periphery of one end in the axial direction by spline fitting, and a cylindrical boss is provided with an internal thread in the center of the protector, and by screwing this boss into the thread, axial movement of the sprocket is fixed, and the boss is further formed with at least one through hole and a C-shaped retaining ring with an inwardly projecting hook at one end. Since the hook of the retaining ring is passed through the through hole and engaged with one of the spline grooves of the cylindrical member, the sprocket can be moved in the circumferential direction simply by fitting it onto the outer periphery of the cylindrical member. Moreover, by simply screwing the protector onto the cylindrical member and engaging the hook of the retaining ring with the spline groove, the axial movement of the sprocket can be prevented, and the protector can be loosened. It can be installed without any problems.

Moreover, the protector and sprocket can be easily removed by pulling out the hook of the retaining ring from the through hole and releasing it from the spline groove.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway front view showing an embodiment of the assembly of the present invention, Fig. 2 is a sectional view taken along the line ■-■ of Fig. 1, and □ Fig. 3 is a partially cutaway front view showing an embodiment of the assembly of the present invention.
4 is a perspective view showing the state in which the retaining ring is held in the protector, 5 is an enlarged sectional view of the main part, 6
7 and 7 show another embodiment, FIG. 6 is a partially omitted cross-sectional view, and FIG. 7 is a cross-sectional view taken along the line ■--■ in FIG. 6. 1... Cylindrical member, 11... Spline groove, 12... Screw, 2... Sprocket, 2a... Minimum diameter sprocket, 5...
...Protector, 51...Inner screw, 52...
... Cylindrical boss, 53 ... Through hole, 6 ...
...Retaining ring, 61...Hook.

Claims (1)

[Scope of utility model registration request] A plurality of spline grooves are provided on the outer periphery of the cylindrical member, and a screw is provided on the outer periphery of one end in the axial direction, and a plurality of sprocket assemblies having different diameters are provided on the outer periphery of the cylindrical member. A disk-shaped protector having an outer diameter larger than the outer diameter of the small-diameter sprocket is formed, a cylindrical boss with an internal thread is formed in the center of the protector, and this boss is screwed into the thread. a C-shaped retaining ring for fixing the axial movement of the sprocket, having at least one through hole formed in the boss, and having a hook projecting inwardly at one end and capable of preventing bullet damage; A sprocket assembly characterized in that the hook of the retaining ring passes through the through hole and engages with one of the spline grooves of the cylindrical member.