JPH0632477Y2 - Adhesive joining device between the front shoulder of the bicycle and the fork stem - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to an adhesive joining device for a front hawk shoulder of a bicycle and a hawk stem.

2. Description of the Related Art In recent years, the body has been made of light metal as much as possible for the purpose of reducing the weight of bicycles. Above all, steel is used for parts such as the hawk stem where light metal cannot be used because of its strength. . However, since light alloys such as aluminum alloys cannot be welded to steel materials, various measures have been taken to join them.

Problems to be Solved by the Invention As described above, the hawk shoulder made of light alloy has been widely used, and the hawk stem must be made of steel because of its strength. As a means for joining and integrating the steel hawk stem and the light alloy hawk shoulder, the joining surface of both is formed into a tapered surface in advance, and the tapered surfaces of both are tightly integrated via an adhesive agent. ing. However, the bonding using this adhesive has a risk of causing a trouble in the steering of the steering wheel due to the separation of the bonded portion due to the load applied to the vehicle body during traveling or the impact force.

Means for Solving the Problems This invention is intended to solve the above-mentioned drawbacks of the prior art. A fork front stem of a fork of a bicycle is integrally provided with a stem of a fork stem projecting a required height from the upper surface of the shoulder. And a female screw is engraved in the insertion hole for connecting the hawk stem that is formed to the bottom of the hawk shoulder, and the required length of the upper inner surface of the opening provided with the female screw is formed into a taper surface that opens upwards. A male screw that is screwed into the female screw hole of the receiving cylinder and a taper portion that fits the tapered surface of the receiving cylinder are provided on the outer periphery of the hawk stem that is joined to the shoulder, and the tapered surface of the receiving cylinder and the hawk stem. While closely aligning the taper part with the axis line of the hawk shoulder and the stem, apply adhesive to the tapered surface of the receiving cylinder and the taper part of the hawk stem, and the threaded part of the female screw of the hawk shoulder and the male screw of the hawk stem. Apply them It is an adhesive joining device between a front hawk shoulder of a bicycle and a hawk stem, characterized in that they are integrated by contacting, screwing, and adhering.

Action Since this device is constructed as described above,
Accurate positioning of the hawk shoulder and hawk stem from the upper surface of the hawk shoulder by the required height, and the taper surface on the hawk shoulder for accurate positioning, screw thread engagement, and tapered contact surface Also, the threaded portion is joined with an adhesive and triple joining means is used together, and it is possible to sufficiently cope with a shock applied to the joining portion and a large external force such as a load.

EXAMPLES Hereinafter, the present invention will be described with reference to the examples shown in the drawings. 1 is a front fork shoulder for bicycle (hereinafter referred to as “hawk shoulder”) made of light alloy, 2 is a hawk stem made of steel, 3 is a hawk stem receiving barrel, An inner surface of the hole, which is provided so as to integrally project from the upper surface of the hawk shoulder to a required height, and which is continuous from the upper end of the receiving cylinder to the bottom surface of the hawk shoulder, for connecting the hawk stem 3a, except for a part above it. A female screw 4 is engraved on the upper part of the upper part, and the remaining upper opening is formed in the upwardly opening tapered part 5.

6 is the lower part of the hawk stem of hawk stem 2,
The hawk shoulder 1 and the hawk stem connecting barrel 3 projecting from the upper surface of the hawk shoulder to a required height integrally have an outer diameter adapted to the hawk stem connecting insertion hole 3a, and the upper part thereof has a hawk stem connecting difference. A male screw 7 is formed on the tapered portion 8 that fits the upper opening tapered portion 5 of the insertion hole 3a, and the lower outer periphery thereof is screwed with the female screw 4 of the insertion hole 3a for connecting the hawk stem.
Is provided.

Then, the male screw 7 of the hawk stem lower portion 6 is screwed into the female screw 4 of the hawk stem connecting insertion hole 3a provided in the hawk stem receiving cylinder 3 of the hawk shoulder 1, and the hawk stem connecting insertion hole 3a. The tapered portion 5 above and the tapered portion 8 of the lower portion 6 of the hawk stem are formed so as to be fitted and closely contacted with each other, and the hawk shoulder 1 and the insertion hole 3a for connecting the hawk stem provided in the hawk stem receiving cylinder 3a are assembled. An adhesive is applied to the engraved portion of the inner female screw 4 and the tapered portion 5, or an adhesive is applied to the outer peripheral surface of the lower portion 6 of the hawk stem, and then the hawk stem 2 is connected to the hawk stem 1 of the hawk shoulder 1. Insertion hole 3a
The hawk stem lower part 6 into the hawk stem connecting hole 3 for connecting the hawk stem to the hawk shoulder 1 while screwing the opposite screw parts together.
The inside of a is closely fitted and adhered, and the adhesive is pressure-bonded and dried.

Effect The hawk stem and the hawk shoulder that are fitted and connected in this way are
Adhesive strength of the adhesive along the entire length of the insertion hole for connecting the hawk stem, including the hawk stem receiving portion that is formed on the upper surface of the hawk shoulder by bringing the tapered surfaces into close contact with each other to give an accurate axial center. The hawk stem and the hawk shoulder are firmly integrated by the screwing of the screw part, and they are not inferior to the fixation by the welding of the same kind of metal.

Therefore, according to the present invention, the front hawk for a bicycle having an accurate axial center is formed, and unlike the conventional adhesive fixing of dissimilar metals using only an adhesive, it is extremely firm and can be added to the vehicle body during running. It has sufficient strength against impact and load.

[Brief description of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a sectional view of a hawk shoulder, Fig. 2 is a front view showing a part of the hawk stem in section, and Fig. 3 is a hawk stem on the hawk shoulder. It is a front view at the time of joining and fixing. 1 ... Bicycle front hawk shoulder, 2 ... Hawk stem, 3 ... Hawk stem receiving barrel, 3a ... Hawk stem connecting hole, 4 ...
Screw, 5 ... Taper part, 6 ... Hawk stem lower part, 7 ...
Screw, 8 ... Tapered part.

Claims (1)

[Scope of utility model registration request] 1. A front hawk shoulder of a bicycle is integrally provided with a hawk stem receiving cylinder projecting a required height from an upper surface thereof, and a female screw is formed in a hawk stem connecting insertion hole formed to the receiving cylinder and a bottom surface of the hawk shoulder. A male thread is formed by engraving a female thread into the female threaded hole of the receiving cylinder, and a hawk stem joined to the hawk shoulder is formed with a required length of the upper inner surface of the female threaded hole. A screw and a taper portion that fits the tapered surface of the receiving cylinder are provided on the outer periphery thereof, and the tapered surface of the receiving cylinder and the tapered portion of the hawk stem are closely contacted to each other so that the axis line of the hawk shoulder and the stem coincides with each other. Of the taper surface of the hawk stem and the taper part of the hawk stem, and the threaded part of the female screw of the hawk shoulder and the male screw of the hawk stem, respectively, and apply the adhesives to the surfaces, screw them together, and bond them together to integrate them. Characteristic, bicycle front hawk shoulder and ho Adhesive bonding apparatus of the Kusutemu.