JPH10329777A - Main shaft structure for bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a main shaft structure for a bicycle which is fixed to a main pipe, simplifies the assembling work, eliminates any adjustment, saves the labor and the labor cost, is effective for converted into a convenient one by easily inserting a fitting pipe in the main pipe and threadly engaged with thread ridges. SOLUTION: A main shaft structure for a bicycle is constituted of a main pipe 1, a fitting pipe 2, a shaft center 3, ball bearings 4, and a screw ring 5, the fitting pipe 2 and the shaft center 3 are attached to the inside of the main pipe 1, and parts near the both ends of the shaft center are covered with the ball bearings 4 respectively. The main pipe 1 is provided with a thread ridge 11 in its one end inside and a conical face 12 in its other inside edge, and the fitting pipe 2 is provided with a thread ridge 21 mated to the main pipe 1 in its one end outside and a conical face 22 mated to the main pipe 1 in the other end so that the fitting pipe 2 is easily inserted into the main pipe 1 and the thread ridges 11, 21 are threadly engaged with each other so as to be fixed on the main pipe 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a bicycle main shaft.

[0002]

2. Description of the Related Art In view of recent industrial development trends, simple manufacturers and consumers in the past have changed their taste into multi-disciplines, not only in terms of convenience in use by consumers, but also in manufacturing factories. The overall technology and cost of the company must be taken into account, and the needs of distributors must be taken into consideration. In addition, environmental protection issues after consumption have been evaluated. Under the above conditions, the present invention has analyzed the various drawbacks of the current bicycle main shaft structure, and as a result, has put emphasis on manufacturing and assembling techniques and has focused on improvement. Therefore, the technical scope of the present invention lies in the manufacture and assembly of the bicycle main shaft structure.

At present, since the five-way pipe is soldered on the body, the entire main shaft must be assembled entirely on the body. However, in the process sharing system, parts production and body production of the main shaft part are divided, so both the bicycle main shaft manufacturer and the body production factory have a relationship with each other, and the manufacturer After the shaft is manufactured, it is packaged and transported to the body factory, and then the body factory assembles it into the five pipes on the body.

The main shaft structure used for a bicycle is initially an assembled structure like the conventional product shown in FIG. 3, and includes a five-way pipe 6, a fitting pipe 7, a shaft core 3, and a ball bearing (shown in the figure). Is a steel ball 4) and a screw cap 9. Ball rail 3 on shaft center 3
1 and a thread 61 at an inner portion near both ends of the five-way pipe 6,
A ball bowl 91 is provided inside the screw cap 9. At the time of assembly, a fitting pipe 7
Then, ball bearings (steel balls 4 are shown) are attached to portions near both ends of the shaft core 3, respectively, inserted into the five-way pipe 6, and the screw cap 9 is combined with the fitting ring 34. When screwed onto the shaft center 3 (the ball bowl 91 of the screw cap 5 holds down the steel ball 4), and both ends are simultaneously rotated appropriately and fixed,
The entire structure of the shaft is completely attached to the five-way pipe 6.
Since the five-way pipe 6 is soldered on the body, the assembly of all the main shafts must be performed entirely on the body, including the large gear portion and the angle between the gear surfaces of the transmission gears of the rear wheels. The adjustment operation for maintaining the angle within the allowable angle is also included.

[0005] However, the above method has the following disadvantages. 1. Installation is difficult and wastes time and labor. Only a coordinator with advanced technology and a wealth of experience at the body factory can make the installation at both ends average and precise. 2. Semi-finished products in the center of the shaft have a high defect rate. If the body factory makes a narrow angle adjustment and confirms that it does not meet the requirements, the entire shaft core will be returned to the main shaft manufacturing factory. The body factory is ready for assembly, and the main shaft manufacturing factory is in re-production. 3. The total manufacturing cost is very high and cannot be reduced.
At the time of reproduction, the main shaft manufacturing plant first removes the shaft core and reproduces the shaft core so that it corresponds to the requirement. Both the body plant and the main shaft manufacturing plant suffer very large losses. 4. High quality control costs. In order to meet the demand for high quality, it is often necessary to remove the shaft core and reproduce it, which is a waste of labor, time and costs. 5. High incidence of defective products. If the assembly at both ends is imbalanced, the shaft center will roll or tilt. 6. High labor costs and high risk factors. At the body factory, an adjustment engineer must be stationed even if no orders are received, leading to intangible production cost increases. If the coordinating technician leaves the production line, the production line will be shut down, greatly affecting the progress of the work process, which is the most serious problem for the body factory.

Therefore, a person proposed a structure as shown in FIG. Fitting tube 7 and two fixing ring caps 8
The installation problem was solved by adding and installing it after the outer part of the body was completed. The bicycle main shaft shown in FIG. 4 is an existing representative structure, which includes a five-way pipe 6, a fitting pipe 7, a shaft core 3, and a ball bearing (the illustrated steel ball 4, screw ring 5 and A ball rail 31 is provided on the shaft center 3 of the fixed ring cap 8), and threaded portions 61, 6 are provided on inner portions near both ends of the five-way pipe 6.
2 and ball bowls 71 and 72 are provided inside the fitting tube 7. In addition, a screw thread 8
The ball bearings (steel balls 4 in the drawing) are respectively placed near both ends of the shaft core 3 during assembly. The screw ring 5 is combined with the cushion ring 32 and the washer 33 and screwed onto the shaft core 3 (the ball rail 51 of the screw ring 5 exerts a force to push up the steel ball 4), so that the shaft core 3 and the fitting pipe are engaged. 7 combined. These are the five pipes
First, the fitting tube 7 and the shaft core 3
First, the two fixing ring caps 8 are simultaneously fitted near both ends of the shaft core 3 in the five-way pipe 6, and the thread 81 of the two fixing ring caps 8 is threaded into the five-way pipe 6. All the main shafts are mounted on the five-way pipe 6 by screwing into the threads 61 and 62 of the pipe 6 and appropriately rotating both ends.

[0007]

However, despite the addition of two fixing ring caps 8 in this method, the following disadvantages remain. 1. Parts increase. Since there are three (the two fixing ring caps 8 are added to the fitting tube 7), resources are wasted and the cost is increased. 2. Manufacturing process increase. Additional production of two fixing ring caps 8. 3. Parts storage space and cost increase. 4. Increase total cost. 5. Increased costs for processes and added environmental protection (society). 6. The assembly procedure is more complicated. After the shaft core 3 is positioned, the two fixing ring caps 8 are screwed in order.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and provide a thread at one end inside a five-way tube, a conical surface at the other inside edge, and a five-way tube at one end outside a fitting tube. Another object of the present invention is to provide a main shaft structure of a bicycle, characterized in that a screw thread to be formed is provided at the other end with a conical surface corresponding to a five-way pipe.

[0009]

According to a first aspect of the present invention, there is provided a bicycle main shaft comprising a five-way pipe, a fitting pipe, a shaft core, a ball bearing, and a screw ring. A fitting tube and a shaft core are provided in the five-through tube, ball bearings are placed near both ends of the shaft center, and a screw ring is screwed onto the shaft center to combine the shaft center and the fitting tube. A thread is provided on the inside of one end of the five-way pipe, a non-slip surface is provided on the inner edge of the other end, and a thread corresponding to the five-way pipe is provided on the outside of one end of the fitting pipe, and a thread is provided on the other end. By providing the corresponding non-slip surface, the fitting tube can be easily inserted into the five-way tube, screwed with each other, and fixed on the five-way tube.

The main shaft structure of a bicycle according to a second aspect of the present invention is the main shaft structure of the bicycle according to the first aspect, wherein the non-slip surface of the five-way pipe and the non-slip surface of the fitting pipe are: The feature is that they are opposing conical surfaces. The bicycle main shaft structure according to claim 3 of the present invention is the bicycle main shaft structure according to claim 2, wherein the non-slip surface of the five-way pipe has a large diameter at an outer end and a large diameter at an inner end. It is a narrow conical surface, characterized in that the non-slip surface of the fitting pipe is a conical surface designed to face the non-slip surface of the five-way pipe.

A bicycle main shaft structure according to a fourth aspect of the present invention is the bicycle main shaft structure according to the second aspect, wherein the non-slip surface of the five-way pipe has a narrow outer end and a smaller inner end. Is characterized in that the non-slip surface of the fitting pipe is designed to be opposite to the non-slip surface of the five-way pipe.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, Embodiment 1 of the present invention
Is composed of a five-way pipe 1, a fitting pipe 2, a shaft core 3, a ball bearing (steel ball 4 shown in the figure) and a screw ring 5, and a ball rail 31 is provided on the shaft core 3, Also inside the fitting tube 2 are ball bowls 23, 2
4 is provided.

A thread 11 is provided inside one end of the five-way pipe 1,
The other inner edge is provided with a “non-slip” conical surface 12,
A thread 21 corresponding to the five-way pipe 1 is provided outside one end of the fitting pipe 2, and a “non-slip” conical surface 22 corresponding to the five-way pipe 1 is also provided at the other end. As described above, the fitting pipe 2 can be easily inserted into the five-way pipe 1 and the threads 11 and 21 can be screwed together and fixed to the five-way pipe 1. At the time of assembling, ball bearings (indicated by steel balls 4) are put on the positions near both ends of the shaft core 3, respectively, and the cushion ring 32 and the washer 33 are combined with the fitting tube 2. It is fixed on the shaft core 3 by the screw ring 5 (the ball rail 51 of the screw ring 5 exerts a force for pushing up the steel ball 4), the shaft core 3 and the fitting tube 2 are combined, and finally, the fitting tube 2 and the shaft The core 3 is inserted into the five-way tube 1, and the threads 11 and 21 are screwed and fixed until the two conical surfaces 12 are firmly positioned.

The conical surface 12 in the first embodiment is designed such that the outer end has a large diameter and the inner end has a small diameter, and the conical surface 22 corresponds to the conical surface 12. Insert from the left end to the right end. Embodiment 2 of the present invention
As shown in FIG. 2, it is composed of a five-way pipe 1, a fitting pipe 2, a shaft core 3, a ball bearing (a steel ball 4 shown in the figure) and a screw ring 5, , A ball rail 31 is provided, and ball bowls 23 and 24 are provided inside the fitting tube 2.

A thread 11 is provided inside one end of the five-way pipe 1, a conical surface 12 for “slip prevention” is provided on the inside edge of the other end, and a screw corresponding to the five-way pipe 1 is provided outside one end of the fitting pipe 2. The mountain 21 is provided at the other end thereof with a “slip-proof” conical surface 22 corresponding to the five-way pipe 1. The fitting tube 2 is easily inserted into the five-way tube 1,
The threads 11 and 21 can be screwed together and fixed to the five-way tube 1. At the time of assembling, ball bearings (indicated by steel balls 4) are put on the positions near both ends of the shaft core 3, respectively, and the cushion ring 32 and the washer 33 are combined with the fitting tube 2. The screw ring 5 is fixed on the shaft core 3 (the ball rail 51 of the screw ring 5 exerts a force for pushing up the steel ball 4), and the shaft core 3 and the fitting tube 2 are combined. The core 3 is inserted into the five-way tube 1, and the threads 11, 21 are screwed and fixed until the two conical surfaces 12, 22 are securely positioned.

The conical surface 12 in the second embodiment is designed such that the outer end has a small diameter and the inner end has a large diameter, and the conical surface 22 corresponds to the conical surface 12. Insert in the left end direction and combine. This part is a difference between the first embodiment and the second embodiment of the present invention.

[0017]

As described above, the main shaft structure of the bicycle according to the present invention can be fixed on the five-way pipe by simply inserting the fitting pipe into the five-way pipe and screwing the threads. Has features. This is effective in simplifying the assembly and mounting work, eliminating the need for adjustment, saving time, saving labor costs, and simplifying the operation. In addition, two fixing screw caps are omitted (three-part conventional type as shown in Fig. 4 is improved to a single type)
This is effective in reducing the number of steps for manufacturing two components and reducing costs.

[Brief description of the drawings]

FIG. 1 is an assembled sectional view of a first embodiment according to the present invention.

FIG. 2 is an assembled sectional view of Embodiment 2 according to the present invention.

FIG. 3 is an assembled sectional view of a conventional product.

FIG. 4 is an assembled sectional view of a conventional product.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Five-way pipe 2 Fitting pipe 3 Shaft core 4 Steel ball (ball bearing) 5 Screw ring 6 Five-way pipe 7 Fitting pipe 8 Fixed ring cap 9 Screw cap 11 Thread 12 Conical surface 21 Thread 22 Conical surface 23, 24 Ball bowl 31 Ball rail 32 Cushion ring 33 Washer 34 Fitting ring 51 Ball rail 61, 62 Thread 71, 72 Ball bowl 81 Thread 91 Ball bowl

Claims (4)

[Claims] 1. A five-way pipe, a fitting pipe, a shaft center, a ball bearing, and a screw ring. A fitting pipe and a shaft center are provided in the five-way pipe, and ball bearings are respectively provided near both ends of the shaft center. The shaft ring and the fitting tube are combined by screwing the screw ring onto the shaft center, and a thread is provided on one inner side of the five-way pipe, and a non-slip surface is provided on the other inner side edge. By providing a thread corresponding to the five-way pipe on the outside of one end of the pipe and a non-slip surface corresponding to the five-way pipe on the other end, the fitting pipe can be easily inserted into the five-way pipe, and the threads can be connected to each other. The main shaft structure of a bicycle, which can be screwed into the main body and fixed on five pipes. 2. The bicycle main shaft structure according to claim 1, wherein the non-slip surface of the five-way tube and the non-slip surface of the fitting tube are opposing conical surfaces. 3. The non-slip surface of the five-way tube is a conical surface with a large diameter at the outer end and a small diameter at the inner end, and the non-slip surface of the fitting tube faces the non-slip surface of the five-way tube. The main shaft structure of a bicycle according to claim 2, wherein the main shaft structure is a designed conical surface. 4. The non-slip surface of the five-way tube is a conical surface with a narrow outer end and a wide inner end, and the non-slip surface of the fitting tube faces the non-slip surface of the five-way tube. The main shaft structure of a bicycle according to claim 2, wherein the main shaft structure is a designed conical surface.