JP2006142972A - Lug made of resin for bicycle frame - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lug made of resin for a bicycle frame with good productivity having both required strength and rigidity. <P>SOLUTION: In the lug made of resin for the bicycle frame, a reinforcement rib is integrally projection-molded to a lug main body and a mounting part projected from the main body by injection-molding using the melting resin constituted by adding/mixing a 40-75 wt.% of a filler having length of 9-14 mm and a diameter of 0.01-1 mm into the thermoplastic resin of the main material. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a resin lug for a bicycle frame that has both required strength and rigidity and high productivity.

  Conventionally, various bicycle frames using resin lugs have been proposed. From the manufacturing method of resin lugs, resin is laminated on a fiber cloth impregnated with resin in consideration of the final shape, and this is set in a mold and placed at a constant temperature, constant pressure, and constant time. Something to be molded has been proposed.

Further, in the lug manufactured by the injection molding process, the lug main body integrally including the mounting portion is performed by the first injection molding performed at the first temperature, and the connecting portion that connects the outside and the mounting portion is the first portion. An injection molding method has been proposed at a second temperature which is lower than the temperature of the first injection molding.
JP-A-7-108971 Japanese Patent Application Laid-Open No. 6-1114876

When the fiber cloth which is the first preceding example is impregnated with a resin and manufactured with a mold, it takes a long time to cure and the production efficiency is not increased.
In the injection molding which is the second preceding example, since the injection molding is performed in two stages, there is a disadvantage that the production efficiency is also poor.

  An object of the present invention is to provide a resin lug for a bicycle frame that solves such a conventional problem.

  The present invention is an injection molding of a molten resin constituted by adding and mixing a filler having a length of 9 to 14 mm, a diameter of 0.01 to 1 mm, and a weight of 40 to 75% to the main thermoplastic resin. There is a resin lug for a bicycle frame in which a reinforcing rib is integrally formed by protruding from a main body of a lug and a mounting portion protruding from the main body.

  Polyamide resin, urethane resin, polypropylene resin, polyphenylene sulfide resin, polyacetal resin, polyethylene resin, high density polyethylene resin, ultra high density polyethylene resin or ABS resin as the main thermoplastic resin It may be used.

  As a filler added and mixed in the thermoplastic resin of the main material, glass fiber, carbon fiber, aramid fiber, stainless steel fiber or PBO (polyparaphenylene benzoxazole) fiber may be used alone or in combination. .

  First, the surface shape is beautiful because it is injected into a mold and molded. Secondly, the external shape of the product and the internal structure such as the hollow can be freely molded by the shape of the mold. Third, because of injection molding, the molding time is short, and mass production of the same molded product is possible. Fourth, since the hardware can be supported in the injection mold, insert molding can be performed and the member can be easily reinforced by the insert. Fifth, since the filler length, diameter, and amount of added mixture are limited, there is no segregation of the filler, and the product strength is stabilized as a whole. Sixth, there are small items. Seventh, in manufacturing, it is difficult to be affected by outside air such as temperature and humidity, and the product performance can be stably manufactured.

  A mold for molding the product shape is prepared. Next, a thermoplastic resin is used as the main resin, and a filler having a length of 9 to 14 mm and a diameter of 0.01 to 1 mm is added to the thermoplastic resin in a weight of 40 to 40. 75% added and mixed, the distributed molten resin material is injected into the mold, and a reinforcing rib of the required thickness is formed integrally with the main body at the mounting part that protrudes from the main peripheral surface of the molded resin lug for bicycle frame Resin lugs for frames.

  The head lug 1 of the first embodiment of the resin lug for bicycle frame according to the present invention will be described below with reference to FIGS. 1 to 3. A mold (not shown) for molding the shape shown in FIGS. 1 to 3 is prepared in advance. Next, a polyamide resin is used as the main material resin from a thermoplastic resin, and the glass fiber filler mixed in the polyamide resin of the main material resin has a filler length of 9 to 14 mm and a diameter of 0. The distribution of glass fibers added to and mixed in the polyamide resin as the main resin is 0.01 to 1 mm, and the weight is 40 to 75%. The distributed molten resin material is injected into a mold, and as shown in FIGS. 1 to 3, the upper pipe mounting base 5b of the upper pipe mounting portion 5 protruding rearward from the upper half rear surface of the main body 3c of the molded head lug 1 is used. The upper surface is integrally formed with the main body, and reinforcing ribs 8 having a required thickness project from the left and right along the longitudinal center line XX of the frame.

  More specifically, the head lug 1 of the first embodiment is formed with a through hole 2 through which a handle and a front fork (not shown) are inserted, and an upper end bearing hole 3a and a lower end bearing hole 3b that are rotatably supported. The main pipe 3c and the upper half back surface 3c1 of the main body 3c are provided with an upper pipe attachment portion 5 including an upper pipe connection portion 5a for fitting and bonding the upper pipe 4 and an upper pipe attachment base portion 5b. On the lower half back surface 3c2, a lower pipe connecting portion 7a for fitting and bonding the lower pipe 6 and a lower pipe mounting portion 7 consisting of a lower pipe mounting base portion 7b are respectively formed projecting, and the upper half back surface 3c1 of the main body 3c is formed. The required thickness reinforcing ribs 8 are formed on the upper surface of the upper pipe mounting base portion 5b so as to protrude right and left along the front-rear center line XX of the frame.

  Next, the upper pipe mounting portion and the hanger lug 9 with the lower pipe mounting portion of the second embodiment of the resin lug for bicycle frame according to the present invention will be described with reference to FIGS. 4 to 6 in advance, similarly to the first embodiment. A mold (not shown) for molding the shape shown in FIGS. 4 to 6 is prepared. Next, as in the first embodiment, a polyamide-based resin is used as the main material resin from a thermoplastic resin. Glass fiber having a filler length of 9 to 14 mm and a diameter of 0.01 to 1 mm is added and mixed in a polyamide resin at a weight of 40 to 75%, and the distributed molten resin material is injected into a mold. 4 to 6, a hanger portion 10a for bearing a crankshaft (not shown), and a vertical pipe connection that protrudes from the upper surface of the hanger portion 10a to a required height, and a vertical pipe 11 is fitted and bonded to the upper end. Standing pipe lower end with section 12 An upper pipe attachment portion 13 comprising an upper pipe connection portion 13a and an upper pipe attachment base portion 13b for fitting and adhering the upper pipe 4 to the front surface from the upper end of the lower end portion 10b of the main pipe 10 and the vertical pipe lower end portion 10b. Similarly, the hanger portion 10a of the main body 10 is provided with a lower pipe attachment portion 14 including a lower pipe connection portion 14a and a lower pipe attachment base portion 14b for fitting and bonding the lower pipe 6 on the front surface of the hanger portion 10a of the main body 10. A chain stay connecting portion 16 for fitting and bonding the chain stay 15 to the back surface of the upper pipe mounting portion 13 and a reinforcing rib on the upper surface side of the upper pipe mounting base portion 13b of the upper pipe mounting portion 13 and the front surface side of the vertical pipe lower end portion 10b of the main body 10 17, the lower surface side of the upper pipe mounting base portion 13b, the front surface side of the vertical pipe lower end portion 10b of the main body 10 and the upper surface side of the lower pipe mounting base portion 14b, and the main body 1 Upright reinforcing ribs 18 to contact the front side of the pipe lower portion 10b in which respectively protrude formed along the longitudinal center line X-X of the frame.

  As an example, although not shown in the drawings, as in the case of a seat lug, the center axis of each of the front upper pipe attachment part and the lower vertical pipe attachment part coincides with the front and rear center line XX of the frame. In the attachment part of the back fork that is branched and formed to the left and right, the reinforcing rib is formed along the respective center axis lines of the attachment part of the back fork without being coincident with the front-rear center line XX of the frame. .

In both the head lug 1 of the first embodiment and the hanger lug 9 with the upper pipe mounting portion and the lower pipe mounting portion of the second embodiment, the connecting portion between the upper pipe 4 and the lower pipe 6 is a shaft portion, so that the reinforcing rib is Although the embodiment in which the main body and the mounting base portion are formed has been shown, in the embodiment in which the upper pipe 4 and the lower pipe 6 are inserted and attached to the inside, a reinforcing rib may be formed on the entire length of the protruding mounting portion. Of course.

Both the head lug 1 of the first embodiment and the hanger lug 9 with the upper pipe mounting portion and the lower pipe mounting portion of the second embodiment use a polyamide-based resin from a thermoplastic resin as a main material resin. Resin, polyphenylene sulfide resin, polyacetal resin, polyethylene resin, high density polyethylene resin, ultra high density polyethylene resin, and ABS resin may be used.

In both the head lug 1 of the first embodiment and the hanger lug 9 with the upper pipe attachment portion and the lower pipe attachment portion of the second embodiment, the filler added and mixed in the main resin was glass fiber, but carbon fiber , Aramid fiber, stainless steel fiber, and PBO (polyparaphenylene benzoxazole) fiber may be used alone or in admixture of two or more.

  Although the length of the filler in the head lug 1 of the first embodiment and the hanger lug 9 with the upper pipe mounting portion and the lower pipe mounting portion of the second embodiment is limited to a range of 9 to 14 mm, it is reinforced when it is 9 mm or less. If the effect is low, 14 mm or more, molding is difficult and fibers are easily exposed on the surface.

  The diameter of the filler in the head lug 1 of the first embodiment and the hanger lug 9 with the upper pipe mounting portion and the lower pipe mounting portion of the second embodiment is limited to a range of 0.01 to 1 mm, but is 0.01 mm or less. If it is, it is difficult to fill the resin, and if it is 1 mm or more, the fibers are hardly associated with each other, and the strength is lowered.

  The ratio of the glass fiber filler added and mixed in the main resin of the head lug 1 of the first embodiment and the hanger lug 9 with the upper pipe mounting portion and the lower pipe mounting portion of the second embodiment is 40 to 75% by weight. Although limited to the range, if 40% or less, the reinforcing effect is low, and if it is 75% or more, the bonding strength of the main resin is weak.

  Accordingly, the provision of the resin lug for a bicycle frame according to the present invention makes a major change in the production of the bicycle frame.

In the resin lug for bicycle frames of the present invention, it is a side view showing the head lug of the first embodiment. Similarly, it is a top view of the head lug of 1st Example. Similarly, it is sectional drawing which follows the AA line of FIG. In the resin lug for bicycle frames of the present invention, it is a side view showing a hanger lug of the second embodiment. Similarly, it is sectional drawing which follows the BB line of FIG. Similarly, it is sectional drawing which follows the CC line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Head lug of 1st Example 2 Through-hole 3a Upper end bearing hole 3b Lower end bearing hole 3c Main body 3c Main body 3c1 Upper half back surface 3c2 Lower half back surface 4 Upper pipe 5 Upper pipe attachment part 5a Upper pipe connection part 5b Upper pipe attachment base 6 Lower Pipe 7 Lower pipe attachment portion 7a Lower pipe connection portion 7b Lower pipe attachment base portion 8 Reinforcement rib 9 Hanger lug with upper pipe attachment portion and lower pipe attachment portion of the second embodiment 10 Main body 10a Hanger portion 10b Lower end portion of standing pipe 11 Standing pipe 12 Standing pipe connection portion 13 Upper pipe attachment portion 13a Upper pipe connection portion 13b Upper pipe attachment base portion 14 Lower pipe attachment portion 14a Lower pipe connection portion 14b Lower pipe attachment base portion 15 Chain stay 16 Chain stay connection portion 17 Reinforcement rib 18 Reinforcement rib XX Center line before and after frame

Claims (3)

  The main part of the thermoplastic resin is 9-14 mm in length, 0.01-1 mm in diameter, and a molten resin composed by adding and mixing 40-75% by weight filler. A resin lug for a bicycle frame, which is formed by integrally projecting a reinforcing rib on a mounting portion protruding from the main body.   Polyamide resin, urethane resin, polypropylene resin, polyphenylene sulfide resin, polyacetal resin, polyethylene resin, high density polyethylene resin, ultra high density polyethylene resin or ABS resin as the main thermoplastic resin The resin lug for a bicycle frame according to claim 1, wherein the lug is used.   It is characterized by using glass fiber, carbon fiber, aramid fiber, stainless steel fiber or PBO (polyparaphenylene benzoxazole) fiber alone or in combination as a filler added and mixed in the thermoplastic resin of the main material. The resin lug for a bicycle frame according to claim 1 or 2.

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