JP2565360Y2 - Clock pin fixing structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a clock pin fixing structure.

[Conventional technology]

In order to facilitate the description of the conventional pin fixing structure, a description will be given in relation to a plastic base plate of a timepiece and a center pipe which is a metal pin. The center pipe secured the fixing force by the interference with the main plate and the contact length.

[Problems to be solved by the invention]

However, the conventional techniques as described above have the following problems.

First, the center pipe made of metal has high rigidity and its diameter does not change even at the engagement portion. In addition, the ground plate made of a plastic material, which is a polymer material, is inferior to metal in rigidity, so that the shape of the engaging portion is also likely to change. In order to hold and fix the metal center pipe by engaging the two different objects, it is necessary to secure the fixing force of the center pipe by increasing the interference between the engagement portion between the metal center pipe and the plastic base plate. Is required. However, there was a disadvantage that the breaking strength of the base plate reached its limit and the base plate was broken.

Also, preventing the ground plate from being damaged by reducing the interference of the engaging portion between the center pipe and the main plate has a disadvantage that the holding force of the central pipe is reduced.

In addition, there are disadvantages such as deterioration of the material due to a sudden change in temperature, and a decrease in fixing force due to compression of the ground plate engaging portion for a long period of time. In addition, the fixing force can be secured by increasing the length of the engaging portion or increasing the interference, but the conventional structure has a limitation on the interference as described above, so that the contact length is increased. The fixing force was supplemented. However, this method has a problem that the timepiece itself becomes thick because the contact length is long.

Therefore, the present invention solves such a problem, and its purpose is to maintain a long-term stable quality without damaging a structural material made of a polymer material, and for a timepiece that does not hinder environmental characteristics. An object of the present invention is to realize a pin fixing structure.

[Means for solving the problem]

The fixing structure of the timepiece pin according to the present invention includes a center pipe made of metal pressed into a structural member made of a polymer material such as plastic, a center wheel guided inside the center pipe, and a center wheel outside the center pipe. In a timepiece pin fixing structure having an hour wheel to be guided, the center pipe has a concave portion into which the structural member is press-fitted and engaged, and a brim portion having a diameter larger than that of the concave portion, and press-fit into the structural member. The flange portion is fixed by the convex portion of the structural member formed by press-fitting engagement with the concave portion, and the collar portion contacts the second wheel side surface of the structural member, and the pointer of the second wheel is removed. It is characterized by receiving force.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Here, the pins are the center pipe, screw pin, weighing shaft,
It refers to a bush or the like.

FIG. 1 is a sectional view of a main part showing an embodiment of the present invention.
Reference numeral 1 denotes a pin, which is a metallic central pipe, and 1-A denotes a concave portion provided in the central pipe. Hereinafter, the concave portion is referred to as an undercut. 2 is a plastic base plate as a structural member, 3 is an hour wheel with an hour hand, 4 is a second wheel with a minute hand, 5 is a fourth wheel with a second hand, and 6 is a second wheel 4 and a fourth wheel 5 Reference numeral 7 denotes a dial plate to be held, and 8 denotes a needle seat for holding the hour wheel 3.

Here, the undercut 1-A is provided in the engagement portion of the metal center pipe 1 and the plastic base plate 2 which is a structural member made of a polymer material, so that conventionally, the interference of the engagement portion and the contact length are provided. The center pipe 1 which has secured the fixing force only by the escape is released to the undercut 1-A by the frictional force of the engaging portion between the metallic center pipe 1 and the plastic base plate 2 and the pressure of the engaging portion. A convex portion is formed in the plastic of the engaging portion of the ground plate 2, which is an undercut 1 of the central pipe 1.
The fixing / holding force is improved by being combined with the concave portion of -A. The interference at this time may be smaller than that of the conventional one, so that the main plate 2 is not damaged, and the holding and fixing can be performed more reliably. This is evident from the experimental results, and the fixing force of the pin fixed with the same interference has secured a value of about twice or more with and without the undercut.

In the embodiment of the present invention, the center pipe pressed into the main plate serving as a timepiece base frame has been described. However, the fourth tenon frame 11 press-fitted into the train wheel bridge 12 shown in FIG. 2 and the main plate 22 shown in FIG. The same applies to the screw pin 21 which is press-fitted into the screw pin 21.

In addition to the undercut 1-A shown in FIG. 1, a similar effect can be obtained by providing the undercut 31-A at the center of the engaging portion, for example, the center pipe 31 press-fitted into the main plate 32 in FIG. It goes without saying that.

[Effect of the invention]

According to the present invention, a center pipe made of metal pressed into a structural member made of a polymer material such as plastic, a center wheel guided inside the center pipe, and an hour wheel guided outside the center pipe are provided. In the timepiece pin fixing structure, the center pipe has a concave portion into which the structural member is press-fitted and a flange portion having a larger diameter than the concave portion, and the concave portion is press-fitted into the structural member. The flange portion is fixed by a convex portion of the structural member formed by press-fitting engagement with the collar member, and the collar portion comes into contact with a second wheel side surface of the structural member and receives a force for detaching the pointer of the second wheel, Due to the frictional force of the engaging portion between the metallic pin and the plastic structural member and the pressure of the engaging portion, a convex portion is formed in the plastic portion of the engaging portion of the structural component that escapes to the concave portion. Fixing and holding together The holding power can be improved.

Furthermore, the removal force in the direction in which the force is mainly applied secures the removal force in the flange portion having a larger diameter than the pressure engagement portion, and the interference setting of the direction press-fit engagement portion that applies only a relatively weak force in the opposite direction is set. Since the size can be reduced, the stress on the plastic structural member can be suppressed to a necessary minimum, and the structural member can be prevented from being broken.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of a timepiece pin fixing structure according to the present invention. FIG. 2 is a sectional view showing a main part of another embodiment of the timepiece pin fixing structure according to the present invention. FIG. 3 is a sectional view of a main part showing another embodiment of the timepiece pin fixing structure of the present invention, similarly to FIG. FIG. 4 is a sectional view of a main part of the embodiment of the present invention shown in FIG. 1 Central pipe 2 Base plate 4 Hour wheel 5 4th wheel 6 Wheel train receiver 7 Dial plate 8 Needle seat 11 Fourth mortise frame 12 Wheel train receiver 21 Screw pin 22 Base plate 31 Central pipe 32 Base plate 1-A Undercut 11-A Undercut 21-A Undercut 31-A Undercut

Claims (1)

(57) [Scope of request for utility model registration] 1. A center pipe made of metal pressed into a structural member made of a polymer material such as plastic, a center wheel guided inside the center pipe, and an hour wheel guided outside the center pipe. In the timepiece pin fixing structure, the center pipe has a concave portion into which the structural member is press-fitted and a flange portion having a larger diameter than the concave portion, and the concave portion is press-fitted into the structural member. And the flange is in contact with a second wheel side surface of the structural member, and receives a force for removing the pointer of the second wheel. Watch pin fixing structure.