JP2017161287A - Balance wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a balance wheel which is not disassembled when receiving impact, and which is difficult to deform by the impact in an axial direction.SOLUTION: A balance wheel includes: a connection component 3 into which a balance staff 5 is inserted; an arm 2 connected to the connection component 3; and a rim 1 connected to the arm 2. Each of the connection component 3, the arm 2, and the rim 1 is formed of a synthetic resin. At least one of the connection component 3 and the rim 1 includes a metal part 4 covered by metal.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a ten wheel used in a mechanical timepiece. More particularly, the present invention relates to a structure of a ten wheel having a function of preventing deformation when a large impact is applied.

  As a speed control device for a mechanical timepiece, a ten wheel that performs reciprocating rotational vibration in combination with a balance spring is used. The normal structure of the ten wheel will be described below. The main part is a ring-shaped member called a rim, and the rim coincides with the central axis of the rim, and the arm that is integrally formed with the rim and arranged along the diameter of the rim. It is fixedly connected by an elongated member in a flat plate shape called. The arm is molded thinner than the thickness of the rim in order to reduce the weight of the ten wheel as much as possible by concentrating it on the rim.

  In such a normal structure, the ten wheel is likely to be deformed when a strong impact is applied particularly in the true axial direction (which is also a direction perpendicular to the ring surface of the rim). That is, as a result of the impact, there is a drawback that the flat arm may be plastically deformed into a mountain shape. When such a deformation occurs, the ten wheel is displaced and interferes (contacts) with other components that are close to each other in the timepiece movement, so that free vibration movement cannot be performed, and the timepiece may stop.

  Patent Document 1 is known as a ten ring structure that can relieve such a tenthal axial impact. In Patent Document 1, the ten wheel has a configuration in which a plastic arm is attached to a metal rim, and the impact in the axial direction is reduced by the elasticity of the plastic arm.

Japanese Examined Patent Publication No. 53-21309 (2nd page, Fig. 2)

  However, the structure as described in Patent Document 1 forms a tenn by forming and fitting a rim and an arm, respectively. Therefore, there is a problem that the rim is detached when the impact is received and the ten wheel is disassembled.

  In addition, the ten wheel composed of a plurality of members is not limited to the one described in Patent Document 1, and it is difficult to make the ten wheel rotation center coincide with the true rotation axis due to variations in assembly accuracy of each part. is there.

  The main object of the present invention is to construct a ten wheel that is not easily deformed by an axial impact without being disassembled when subjected to an impact. Further, a secondary purpose is to prevent the eccentricity due to the assembly error.

  The ten wheel of the present invention employs the following configuration in order to achieve the above object.

  A ten wheel having a connecting part into which a tenth is inserted, an arm connected to the connecting part, and a rim connected to the arm, each of the connecting part, the arm and the rim being formed of a synthetic resin, At least one of the connecting part and the rim has a metal part covered with metal.

  By configuring in this way, it is possible to obtain a ten wheel that is not easily deformed by an axial impact without being disassembled when subjected to an impact.

  The metal part may be divided into a plurality along the outer periphery of the rim.

  By comprising in this way, the concrete structure which improved the impact resistance of the ten wheel can be provided.

  Further, an intermediate layer may be provided between the metal and the synthetic resin.

  By comprising in this way, the electroconductivity to the resin member can be provided at the time of plating.

  By covering a part of the ten wheel molded with the synthetic resin with metal, it is possible to configure the ten wheel having the moment of inertia necessary for the vibration motion without being decomposed when subjected to an impact.

1 is a perspective view of a first embodiment of the present invention. It is sectional drawing explaining a mode that the ten wheel of 1st Embodiment of this invention was cut | disconnected by cutting line AA. It is the enlarged view to which the rim | limb partial cross section which is the area | region B of FIG. 2 of 1st Embodiment of this invention was expanded. It is sectional drawing explaining the manufacturing process of 1st Embodiment of this invention. It is a top view explaining the modification of 1st Embodiment of this invention. It is a perspective view explaining 2nd Embodiment of this invention. It is sectional drawing explaining a mode that it cut | disconnected by the cutting line CC of FIG. 6 explaining 2nd Embodiment of this invention.

  The present invention is a ten wheel having a connecting part into which a tenth true is inserted, an arm connected to the connecting part, and a rim connected to the arm, wherein the connecting part, the arm and the rim are each made of synthetic resin. And at least one of the connection part and the rim has a metal part covered with a synthetic resin by a metal.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Principal Structure of First Embodiment: FIGS. 1 and 2>
A first embodiment of the ten wheel of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view of a completed ten wheel. FIG. 2 is a cross-sectional view taken along the line AA of FIG. 1 for showing details of the structure of the rim 1.

As shown in FIG. 1, the ten wheel is composed of a rim 1, an arm 2, and a connection part 3, and a tenth true 5 is inserted and fitted into the connection part 3. The rim 1 is a ring-shaped member that gives a necessary moment of inertia to the ten wheel, and is formed so that a metal portion 4 that is a metal covers a part of the rim 1. Further, it is connected to one end of a flat arm 2 on the inner periphery of the rim 1. The other end of the flat arm 2 is connected to the connection component 3, and the rim 1 is supported by the connection component 3 via the arm 2. The connecting component 3 has a substantially cylindrical shape, and has an opening that fits the tenth true 5 at the center. The tenth 5 is a rotating shaft of the ten wheel, and has a cylindrical shape that fits into the connecting part 3. The upper end and the lower end of the tenth stem 5 are usually processed to be thin to reduce rotational friction to form a relief portion. The tenon portion is inserted into a hole stone that is a radial bearing, and the tip portion is received by a stone receiving stone that is a thrust bearing.

  As shown in FIG. 2, the arm 2 has a shape in which the rim 1 and the connection component 3 are connected to each other. The arm 2, the rim 1, and the connecting component 3 can be made of a synthetic resin material such as ABS resin, and are integrally formed by a known technique such as mold processing. Thus, manufacturing variations can be suppressed by integrally processing the arm 2, the rim 1, and the connection component 3.

  Metal parts 4 are formed on the upper surface, the lower surface, and the outer peripheral side surface of the rim 1. Although copper is used for the metal part 4, it is not limited to this, Materials, such as nickel, tin, chromium, gold | metal | money, or these alloys, can be used. A plating technique can be used as the forming method.

  When the ten wheel having such a structure receives an impact in the axial direction, the degree of deformation of the arm 2 is determined by the characteristics of the material used for the arm 2. The synthetic resin material has a lower elastic modulus than the metal material, and the deformation amount when the same load is applied to the same shape is larger than that of the metal material. Therefore, even if the same load as that of the plastic resin arm is plastically deformed, the deformation can be suppressed by contact with other timepiece parts before plastic deformation.

  As a result, the deformation of the arm portion when subjected to an impact is limited to the deformation within the elastic range of the synthetic resin, and can be restored to its original shape even when subjected to the impact.

  Further, as described above, the structure in which the rim 1, the arm 2 and the connection component 3 are integrally molded eliminates the need for assembling individually manufactured rim components and arm components, and prevents eccentricity of the ten wheel due to assembly errors. be able to.

  Furthermore, as described above, the arm and the connecting component that occupy the inner peripheral portion of the ten wheel are made of low specific gravity synthetic resin, and the high specific gravity metal member is disposed only on the rim portion that is the outer peripheral portion. As a result, the rotation radius of the ten wheel is increased, and reciprocating rotational vibration that is not easily affected by disturbance can be obtained.

<Description of Method for Forming Metal Part 4: FIGS. 3 and 4>
Next, the manufacturing method of the ten wheel according to the present embodiment will be described with reference to FIGS. 3 is an enlarged view of region B in FIG. 2, and FIG. 4 shows a manufacturing process of the metal part 4 in FIG.

  In this embodiment, the metal part is placed on the synthetic resin by using a resin plating technique. Here, since the member for resin plating is the integrally formed rim 1, arm 2, and connection component 3, it is preferably performed before the tenthal stem 5 is inserted and fitted into the opening of the connection component 3.

  As shown in FIG. 3, a plurality of micro holes 11 are formed on the surface of the rim 1, and a nickel layer that is an intermediate layer 6 is formed on the surfaces of the micro holes 11 and the rim 1. Further, copper which is the metal portion 4 is formed on the intermediate layer 6. The manufacturing method of this configuration will be described in detail with reference to FIG.

First, as a pre-process for imparting conductivity to the resin surface, electroless nickel plating is performed. The electroless nickel plating process will be described with reference to FIGS. 4 (a) and 4 (b). As shown in FIG. 4A, as a step of performing electroless nickel plating, first, the surface is etched to provide micropores 11 to impart hydrophilicity to the synthetic resin surface of the rim 1. In the etching step, a mask or the like may be formed in the region of the arm 2 or the connection portion 3 that does not require the microhole 11.

  Next, a palladium catalyst is adsorbed in the micropores 11. This is because a chemical reaction occurs using the palladium catalyst as a nucleus, and nickel plating is performed on the resin surface. Thereby, as shown in FIG.4 (b), the intermediate | middle layer 6 is formed by nickel plating on the synthetic resin surface of the micropore 11 and the rim | limb 1. FIG. The intermediate layer 6 is firmly adhered to the resin surface by the anchor effect by the micro holes 11.

  Next, as shown in FIG.4 (c), the intermediate layer 6 is electroplated and copper which is the metal part 4 is plated. The thickness of the metal part 4 is only required to secure a weight necessary for obtaining a moment of inertia for the reciprocating vibration movement of the ten wheel in a predetermined cycle. In the case of copper, the thickness is several tens to several hundreds of microns. Is preferable.

  Further, by making the copper 4 thick, cracking of the plating film can be prevented, and the smoothing action is strong, and the micropores provided during the electroless nickel plating process can be smoothed, and the appearance is excellent.

  The plating material is not limited to copper, and nickel, chromium, tin, gold, or the like may be used. Further, a protective film may be further formed on the plated copper, or nickel or chromium may be further plated on the copper in order to obtain a larger moment of inertia.

  The method of manufacturing such a ten wheel is not limited to the above plating, but is performed using an insert method in which a resin and a metal are integrally formed using a mold, or an aerosol deposition method in which metal fine particles are sprayed on the resin surface. May be.

<Description of Modification of First Embodiment: FIG. 5>
Next, a modified example of the metal part of the first embodiment will be described with reference to FIG. The difference between this modification and Embodiment 1 is the structure of the metal part 41, and the other configuration is the same as that of Embodiment 1. FIG. 5 is a plan view of a modification of the first embodiment. As shown in FIG. 5, the metal part 41 provided in the rim part is divided and provided so as to be rotationally symmetric with respect to the tenth truth 5 as an axis.

  The moment of inertia of the ten wheel is determined by the amount of metal plated on the rim. At that time, the moment of inertia can be adjusted by adjusting the plating thickness, but if the plating amount is adjusted by dividing the metal part 41 as shown in FIG. The stress generated in the resin member by the metal film can be reduced, and deformation of the ten wheel can be prevented.

<Principal Structure of Second Embodiment: FIGS. 6 and 7>
Next, a second embodiment of the ten wheel according to the present invention will be described with reference to FIGS. The difference of the second embodiment from the first embodiment is that a metal part is also provided on the surface of the connection component 3. 6 is a perspective view of the ten wheel according to the second embodiment, and FIG. 7 is a cross-sectional view taken along the line CC in FIG.

  As shown in FIGS. 6 and 7, a metal portion 42 is formed on the upper and lower surfaces of the connection component 3 in the same manner as the rim 1. By providing the metal part 42 also in the connection part 3, the connection part 3 of the ten wheel and the tenth true 5 can be more firmly engaged. In addition, deformation of the ten wheel due to resin deformation at the time of fitting and displacement of the ten wheel rotation shaft can be prevented.

The metal part 42 can be formed by plating or the like, similar to the metal part 4. When the metal part 42 and the metal part 4 are made of the same material, both the metal part 4 and the metal part 42 can be formed simultaneously in the same plating step. Further, when the metal part 42 is formed using a material different from that of the metal part 4 in order to make the fitting with the tenth true 5 stronger, it is performed in a separate process or the same plating process. Later, only the region of the metal part 42 may be additionally plated.

  In the second embodiment, the metal part is provided on both the rim 1 and the connection part 3. However, the metal part may be provided only on the surface of the connection part 3. Also in this case, the impact resistance of the ten wheel can be improved, and the fitting strength with the tenth true 5 can be increased.

  The present invention has a high industrial applicability because it can provide a configuration of a ten wheel that can increase impact resistance and prevent eccentricity due to assembly errors.

DESCRIPTION OF SYMBOLS 1 Rim 11 Micro hole 2 Arm 3 Connection component 4, 41, 42 Metal part 5 Ten true 6 Intermediate layer

Claims (3)

A ten wheel having a connecting part into which a tenth true is inserted, an arm connected to the connecting part, and a rim connected to the arm,
The connecting component, the arm and the rim are each formed of a synthetic resin,
At least one of the connecting part and the rim has a metal part covered with metal. The ten wheel according to claim 1, wherein the metal part is divided into a plurality of parts along the outer periphery of the rim. The ten wheel according to claim 1 or 2, further comprising an intermediate layer between the metal and the synthetic resin.

Images