JPH05307089A - Manufacture of watch hand - Google Patents

Abstract

PURPOSE:To provide watch hands thin and presenting three-dimensional sense and a method of manufacturing them. CONSTITUTION:In manufacturing hands for a watch, hand body 24 and seat 22 are formed by a surface press process prior to formation of a boss 29 and a boss hole 28. Therefore, increasing the pressure of the surface-press process does not influence the precision of the boss hole. When the boss 29 and boss hole 28 are formed by the surface-press process, a curved surface 30 can be formed without producing burrs at the bore of the lower opening of the boss hole 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pointer for a timepiece and a method for manufacturing the same, and more particularly to a high quality thin hand and a method for manufacturing the thin needle by surface pressing.

[0002]

2. Description of the Related Art A conventional timepiece pointer is manufactured through the steps shown in FIGS. That is, first, the metal strip 2 shown in FIG. 9 is continuously pressed to form the slits 4 and the recessed holes 6 shown in FIG. Next, FIG.
The outer shape 8 of the pointer is removed as shown in FIG. 2, and then the pointer is bent and removed from the strip 2 at the same time as shown in FIG. 12 and FIG. After that, the pointer was completed by applying decoration such as plating.

[0003]

As shown in FIG. 14, the pointer formed by the above conventional manufacturing method has a seat thickness T1 substantially equal to the body thickness T2. Seat thickness T1
When the body thickness T2 and the body thickness T2 were the same, the surface of the pointer became flat and a high-class feeling could not be obtained.

Generally, the seating thickness T1 is the body thickness T2 in the face pressing process.
In order to form the pointer so as to be thicker than that, it is necessary to increase the pressing force when the surface is pressed. However,
When the pressure is increased in this conventional manufacturing method, there arises a problem that the hole diameter accuracy of the already formed hole is reduced. Then, in order to prevent the deformation of the hole, the pin was inserted and then the surface was pressed. However, the pin was sometimes caught and the pin could not be removed.

As the timepiece becomes thinner, it is required to make the hands thinner. When the pointer is made thin in this way, the three-dimensional effect is lost. Therefore, it is tried to make the upper surface of the pointer into a curved round shape to give a three-dimensional effect. However, if the pointer is made thin, the amount of material will be small, so it is difficult to make it in the round shape, and as mentioned above, it was not possible to increase the pressing force by the conventional manufacturing method, so make it the round shape. I couldn't. Therefore, conventionally, as shown in the cross-sectional view of FIG. 13, the whole pointer is bent in a mountain shape to give a three-dimensional effect, but there is a problem that the thickness of the pointer becomes larger than that of the band material.

Further, in order to form the hole by the conventional manufacturing method, the pilot hole 12 is provided in the strip 10 as shown in FIG. 15, and then the hook 14 is made out on the lower surface side as shown in FIG. As shown in FIG. 17, finish punching is performed to adjust the size of the hole diameter. Thereafter, in order to facilitate the attachment of the movement to the pointer shaft, the inner circumference 18 of the lower opening of the hakama 14 was chamfered as shown in FIG. However, when this chamfering is performed, as shown in FIG. 18, burrs 20 are generated in the internal holes, which rather makes it difficult to attach the burrs to the pointer shaft.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a watch pointer for a timepiece which is thin and has a three-dimensional appearance, and a manufacturing method thereof.

[0008]

The timepiece pointer of the present invention comprises:
In a timepiece pointer integrally formed with a needle body, a seat, and a hook, the timepiece pointer includes a needle body and a seat made by surface pressing, and a hook and a hole made by the surface pressing. The inner circumference of the lower surface of the hole is formed by a curved surface.

Further, the method of manufacturing the pointer for a timepiece of the present invention is
In a method for manufacturing a pointer for a timepiece having a needle body and a seat and a hook and a hook hole continuously using a metal strip,
A step of forming a through hole such as a pilot hole or a slit in the band material, a step of forming a needle body and a seat by surface pressing using a mold on the band material, and a mold continuous with the needle body A step of forming a hook and a hook hole by surface pressing using, a step of performing finish processing such as diamond cutting, honing, polishing, etc. on the surface of the timepiece pointer having the needle body and the seat and the hook, It is characterized in that it comprises a step of pulling out the timepiece pointer from the band material and a step of subjecting the timepiece pointer to decoration treatment such as plating, printing, painting and the like.

[0010]

In the method of manufacturing a timepiece pointer according to the present invention, the needle body and the seat are formed by surface pressing before forming the hook and the hook hole. Therefore, even if the pressing force of the surface pressing is increased, the accuracy of the hole is not affected. Therefore, make the needle body of the thin pointer into an instep shape,
The seat thickness can be made higher than the body thickness, giving a high-class feeling. Further, when forming the hook and the hook hole by surface pressing, a curved surface can be formed without generating burrs on the inner circumference of the lower opening of the hook hole, and the attachment to the pointer shaft becomes easy.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a sectional view of a timepiece hands according to an embodiment of the present invention, and FIG. 2 is a sectional view of its needle body.

As shown in FIG. 1, the pointer in this embodiment has a seat thickness T3 formed to be thicker than a body thickness T4, and a seat 22 has a shape higher than a needle body 24. Further, as shown in FIG. 2, the needle body 24 has an upper surface formed in a rounded shape having a curved surface.

Further, a curved surface 30 formed by surface pressing is provided on the inner periphery of the lower opening of the hook hole 28 provided in the hook 29.

The upper surface side of the pointer is a molding surface formed by surface pressing, and has a curved surface as a basic surface as described above. At this time, a stress layer due to processing strain is formed on the surface layer of the needle body 24, so that the needle body 24 becomes a curved convex warp. Further, in order to eliminate the convex warp of the needle body 24 and make it a flat surface, when performing the processing of pulling out the pointer from the band material 32 described later, a die punch is applied from the lower surface direction of the pointer to lower the needle body 24. A stress layer surface due to processing strain is formed on the surface of the needle body 24 so as to eliminate the convex warp of the needle body 24 and form a flat surface. If the convex warp is large, the convex warp is removed by removing it with a die using a punch whose surface is roughened by honing or by flattening with a die from the lower surface of the pointer.

Next, a method for manufacturing the timepiece hands will be described. First, as shown in FIG. 3, the metal strip 32 is pressed to form pilot holes 34, slits 36, and windows 38.

Next, as shown in FIG. 4, the strip 32 is sandwiched between the coining punch 42 and the coining die 44,
By pressing the surface with the coining punch 42, as shown in FIG. 5, the needle body 40 and the seat 47 of the pointer are formed in a round shape.

After that, by further similar surface pressing processing, a hook 46 and a hook hole 48 as shown in FIG. 6 are formed. At this time, the hook hole 48 is formed by the straight portion 54 of the pin 52 of the coining die, and the inner circumference of the lower opening of the hook hole 48 is formed by the curved surface portion 56 on the curved surface 50.

After that, finish processing such as diamond cutting, honing and polishing is applied to the surface of the pointer.

Next, the pointer is pulled out from the strip 32.

After that, the pointer is finished by applying decoration treatment such as plating, printing and painting.

In this embodiment, the needle body 40 and the seat 47, the hook 46 and the hook hole 48 are formed in separate steps, but they can be formed simultaneously in the same step. In addition, in this embodiment, the pointer is removed after finishing, but after the pointer is removed,
You may give finish processing and decoration processing.

Further, the hook hole can be formed by face pressing in the same manner whether it is a through hole penetrating the pointer or a blind hole as shown in FIG.

[0023]

According to the present invention, the seat thickness can be made thick and the body thickness can be made thin, and it is possible to provide a pointer with a three-dimensional effect and a high-grade feeling even with a thin pointer.

Further, according to the present invention, since the needle body is formed before or at the same time as forming the hook hole, it is possible to increase the pressing force at the time of carrying out the surface pressing work, and thereby the seat thickness is increased. The needle body can be made thick, and the needle body can be made thin and round in shape.

Furthermore, since the inner circumference of the lower opening of the slotted hole can be formed into a curved surface for chamfering, burrs do not occur and can be easily attached to the pointer shaft without chamfering or deburring. it can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a timepiece hands according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the timepiece hands shown in FIG.

FIG. 3 is a view showing a state in which a through hole is formed in a band material for manufacturing the timepiece pointer shown in FIG.

FIG. 4 is a cross-sectional view showing a state in which surface pressing is performed on the strip shown in FIG.

FIG. 5 is a view showing a band member having a needle body formed by subjecting the surface pressing process shown in FIG.

FIG. 6 is a view showing a state in which a strip is formed on the strip shown in FIG.

FIG. 7 is a cross-sectional view showing a hook hole and a pin in the step of forming the hook hole shown in FIG.

FIG. 8 is a cross-sectional view showing an example in which a hook hole of a timepiece pointer is formed of a blind hole.

FIG. 9 is a view showing a strip in a conventional manufacturing process.

FIG. 10 is a diagram showing a state in which a slot hole or the like is formed in the strip shown in FIG.

FIG. 11 is a view showing a state in which the outer shape of the pointer is punched on the strip shown in FIG.

12 is a diagram showing a pointer extracted from the strip shown in FIG.

13 is a cross-sectional view taken along the line AA of FIG.

FIG. 14 is a cross-sectional view of a pointer manufactured by a conventional manufacturing method.

FIG. 15 is a cross-sectional view showing a state in which a pilot hole is provided in a strip material when forming an internal hole by a conventional manufacturing method.

16 is a cross-sectional view showing a state in which the strip material shown in FIG. 15 has been subjected to peeling processing.

FIG. 17 is a cross-sectional view showing a state where finishing processing is performed on the hook hole shown in FIG.

FIG. 18 is a cross-sectional view showing a state where the inner circumference of the lower opening of the hakama shown in FIG. 17 is chamfered.

[Explanation of symbols]

 22 Seat 24 Needle 28 Hakama Hole 29 Hakama 30, 50 Curved Surface 32 Band Material 34 Pilot Hole 36 Slit 38 Window 40 Needle 46 Hakama 47 Seat 48 Hakama Hole

Front Page Continuation (72) Inventor Sumio Fujiwara No. 25 North Industrial Park Kitakami City, Iwate Prefecture Ageo Seisaku Co., Ltd. (72) Inventor Masaaki Kumasaka No. 2 25 Kita Industrial Park Kitakami City Iwate Ageo Seisaku Stock Co., Ltd. In-house (72) Inventor Yusuke Sugawara 2-25 No. 25 Kita Industrial Park, Kitakami City, Iwate Prefecture

Claims (5)

[Claims] 1. A timepiece pointer integrally formed with a needle body and a seat, and a hook, wherein the timepiece pointer includes a needle body and a seat formed by surface pressing and a hook and a hole formed by surface pressing. And a pointer for a timepiece, characterized in that the inner circumference of the lower surface of the hole is composed of a curved surface. 2. The surface of the needle body and the seat is formed by a surface pressing forming surface formed by surface pressing, and the lower surface of the needle body is formed by a stress layer surface that regulates warpage by surface pressing. The timepiece pointer according to claim 1. 3. A method for manufacturing a timepiece pointer having a needle body and a seat, and a hook hole and a hook hole continuously using a metal band material, wherein a through hole such as a pilot hole or a slit is formed in the band material. And a step of forming a needle body and a seat by surface pressing using a mold on the band material, and forming a needle and a hole by continuous surface pressing using a mold on the needle body. A step of forming, a step of performing finish processing such as diamond cutting, honing, polishing, etc. on the surface of the timepiece pointer having the needle body and seat and the hook, and a step of pulling out the timepiece pointer from the band member, A method of manufacturing a timepiece pointer, comprising a step of subjecting the timepiece pointer to a decorative treatment such as plating, printing, painting or the like. 4. The method for manufacturing a timepiece pointer according to claim 3, wherein the needle body and the seat, the hook and the hook hole are formed in the strip in the same step by surface pressing using a die. 5. The method for manufacturing a timepiece pointer according to claim 3 or 4, characterized in that the hole of the hakama is a blind hole or a through hole formed by surface pressing using a mold.