JPH0894769A - Tubular wheel for watch and manufacture thereof - Google Patents

Abstract

PURPOSE: To manufacture a tubular wheel for a watch quickly at low cost by subjecting a planar body repeatedly to drawing to form a tubular covered protrusion and then punching through the covered part to form a tubular part. CONSTITUTION: A planar body 1 of metal (e.g. phosphor bronze) is pressed repeatedly to form a tubular bottomed protrusion 2. The protrusion 2 is then press formed to match the shape at the tubular part of tubular wheel of a watch. Subsequently, the cover part 2a of the protrusion 2 is punched through by press to make an opening 3a thus completing a tubular part 3. The planar body 1 around the tubular part 3 is then 'drawn in' by press to form a disc gear part 4 having teeth 4a. Finally, the tubular part 3 and the gear part 4 are 'drawn out' from the peripheral planar body 1 to complete a tubular wheel for the watch. Since the gear part 4 is temporarily 'drawn in' before being 'drawn out', durability of die is enhanced and the accuracy at the gear part 4 is also enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timepiece wheel and its manufacturing method.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a hour wheel and a wheel, the cylindrical portion and the gear portion have been formed by cutting.

[0003]

However, in the above-described conventional manufacturing method, it is necessary to form the shape of the hour wheel and the tooth profile by cutting using the cutting material, and these cutting steps take time. However, there is a problem that the manufacturing cost becomes high.

Therefore, the present invention is to solve the above-mentioned problems, and an object thereof is to obtain a manufacturing method capable of manufacturing a timepiece hour wheel quickly and at low cost.

[0005]

The timepiece hour wheel of the present invention comprises:
It is characterized in that a plate-shaped body is repeatedly drawn to form a cylindrical protruding portion with a lid, the protruding portion is molded, and then the lid portion of the protruding portion is removed to form a tubular portion. .

[0006] Here, it is preferable that the periphery of the tubular portion of the plate-like body is pulled out in a gear shape to form the gear portion.

The timepiece wheel manufacturing method of the present invention comprises a drawing step in which a plate-shaped body is repeatedly drawn to form a cylindrical protrusion with a lid, and the timepiece is formed by molding the protrusion. The method includes a forming step of forming a tubular portion of the hour wheel, and a lid removing step of removing the lid portion of the protruding portion to form a tubular portion of the hour wheel and pinion.

In this case, it is preferable that, in the molding step, a relief shape at the time of molding is formed in a region included in the removal portion in the lid removal step in the lid portion of the tubular portion.

Further, it is preferable to provide a tooth profile removing step of forming a gear portion by removing the peripheral portion of the projecting portion of the plate-like body into a gear shape after the extracting step.

At this time, the tooth profile removing step includes a step of removing the gear portion from the plate-shaped body and a step of removing the gear portion from the plate-shaped portion of the gear portion. It is desirable to configure it with the removal step.

[0011]

According to the first or third aspect of the present invention, instead of the conventional cutting process, it can be manufactured by a press process including a drawing process, a forming process, and a removing process. Therefore, the manufacturing process is rapid and low cost. it can.

According to the second aspect or the fifth aspect, the gear portion can be formed by punching as well, so that it is possible to perform more rapid processing.

According to the fourth aspect, since the excess meat can be released at the time of molding, the molding can be performed with high accuracy, and the relief-shaped portion is removed in the lid removing step. It is possible to efficiently manufacture the hour wheel without affecting the above.

According to the fifth aspect, the gear portion is formed in two steps, that is, the removal and the removal, so that the load on the mold is reduced, the durability is improved, and the gear portion is formed with high accuracy. You can

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of a timepiece wheel and wheel manufacturing method according to the present invention will be described with reference to the drawings. FIG. 1 is a process cross-sectional view showing the overall process of manufacturing the hour wheel and pinion according to this embodiment. The outline of the present embodiment is as follows: (b), (c) for the plate-shaped body 1 made of metal (for example, phosphor bronze) shown in (a).
As shown in (d), the drawing process is repeatedly performed by press working to form the cylindrical protruding portion 2 with a cover as shown in (d). Next, the protrusion 2 is pressure-molded to have a shape that matches the shape of the tubular portion of the hour wheel and pinion as shown in (e). Further, the lid portion 2a of the protruding portion is punched out by a press to form an opening 3a as shown in (f), and the tubular portion 3 is completed.

Next, by pressing the plate-shaped body 1 around the cylindrical portion 3 into a tooth shape by pressing, a disc-shaped gear portion 4 having a tooth profile 4a is formed as shown in (g). Form. Finally, as shown in (h), the timepiece hour wheel is completed by removing the tubular portion 3 and the gear portion 4 from the surrounding plate-shaped body 1.

The above-mentioned processing steps are applied to the strip-shaped (ribbon-shaped) plate-shaped body 1 shown in FIG. In this plate-shaped body 1,
A plurality of pilot holes 11 formed in two rows at equal intervals along both edges in the width direction, and punched holes 12, 13, 14, formed at equal intervals between the rows of pilot holes 11. 15
Are formed by press working. Due to the punched holes 12, 13, 14, 15, the support bridge portions 16, 19 and the support arm portions 17, 19 are formed in the central portion of the plate-shaped body 1.
Disk-shaped island portion 2 supported by 18, 20, 21
2 is configured.

FIG. 3A and FIG. 3B are enlarged views of the vicinity of the island-like portion 22 during the manufacturing process. As shown in FIGS. 1A to 1D, FIG.
A state in which a depression 30 corresponding to the projecting portion 2 is formed in the center of the island-shaped portion 22 by drawing processing by a press is shown. The recess 30 is gradually covered by a drawing (or has a bottom).
Corresponding to the protruding portion 2 that is formed into a cylindrical shape, it is transformed into a glass (cup) shape. In this embodiment, 1
By drawing 0 times, the shape shown in FIG. This drawing is shown in detail in FIG. Here, 2-1, 2-4, and 2-6 are the shapes after the first, fourth, and sixth drawing processes, respectively. Initially, make a large bowl-shaped depression, and gradually finish the rising part to a vertical wall.

In FIG. 3B, the gear surface 40 of the gear portion 4 is formed in a disk shape centering on the depression 30 in the island-shaped portion 22 by "extraction" by the press working shown in FIG. 1 (g). The state is shown. This "extraction" process is performed by using a die having a tooth-shaped opening for forming the tooth profile 4a of the gear portion 4 and a punch having a cross-sectional shape corresponding to the opening shape of the die to form the island-shaped portion 22. It is applied by sandwiching from above and below. Here, when the punch is completely inserted into the opening of the die, the gear portion 4 is “pulled out” from the island portion 22, but without removing the gear portion 4 from the island portion 22, the portion of the tooth profile 4a is removed. The gear portion 4 is “pulled out” by allowing the gear portion 4 to be held in the plane of the island portion 22 only by being separated from the surrounding island portion 22 by the breakage.

As shown in FIG. 3B, the cylindrical portion 3 and the gear portion 4 which are “extracted” are provided with a die having an opening having a diameter matching the outer diameter of the gear portion 4 and the die. It is "pulled out" by the punches that have been made, and the hour wheel is completed.
As described above, by temporarily "pulling" the gear portion and then "pulling it out", the durability of the mold is improved and the gear portion with high accuracy can be formed.

FIG. 5 shows a step of forming the protrusion 2 shown in FIG. 1D to form the outer shape of the cylindrical portion 3 of the hour wheel and pinion as shown in FIG. 1E. is there. The protrusion 2 is pressure-molded by the punch A and the die B shown by the chain line in the figure. In the figure, C indicates the contact surface of the stripper.
Here, the solid line is the cross-sectional shape of the protrusion 2 before molding, and the broken line X is the cross-sectional shape of the protrusion 2 after molding. A press-fitting surface 2b of the hour hand, a tapered surface 2c, and an end surface 2d are formed on the outer surface side of the protrusion 2 in accordance with the shape of the die B. Where die B
1 (f), there is formed a relief portion Ba into which the molded extra meat is gathered in the lid portion 2a which is removed when the opening 3a shown in FIG. 1 (f) is formed. The thickened part becomes thick. Since this thick portion is removed later by forming the opening 3a, the shape of the tubular portion 3 is not affected by any shape.

A concave portion 2e peculiar to the drawing process is formed on the upper portion of the wall surface of the protruding portion 2, but this concave portion 2e disappears completely in the molding step. In this molding process, the recess 2
In addition to eliminating formation defects in the previous process such as e, the shape accuracy required for the hour wheel is secured. For example, the press-fitting surface 2b of the hour hand positions the hour hand. Further, since the inner peripheral surface of the protruding portion 2 determines the center of rotation when the pointer is rotationally driven, it must be molded with high accuracy.

As described above, in this embodiment, the protrusion is formed by drawing, and after the protrusion is molded,
Since the cylindrical part is formed by drilling,
It is possible to manufacture a timepiece hour wheel in a short time and at low cost without performing cutting work as in the past.

Further, in the molding step, since the relief portion is formed in the mold in the lid portion 2a of the protruding portion 2 so that the excess meat at the time of molding escapes, the molding can be performed with high accuracy without affecting the front and rear steps. It can be performed.

Further, in forming the gear portion, by performing "extracting" and "extracting", it is possible to enhance the durability of the mold as compared with the case where "extracting" is performed at a time, and The accuracy of can be improved.

In the present embodiment, the belt-shaped plate-shaped body 1 is sequentially moved by the conveying means, so that a plurality of island-shaped portions arranged and formed on the plate-shaped body 1 are sequentially fed. Therefore, the productivity can be greatly improved as compared with the conventional manufacturing process by cutting work, and the labor is also reduced, which is a very remarkable effect.

[0027]

As described above, the present invention has the following effects.

According to the first or third aspect of the present invention, instead of the conventional cutting process, it can be manufactured by a press process including a drawing process, a forming process, and a removing process. Therefore, the manufacturing process is quick and low cost. it can.

According to the second aspect or the fifth aspect, the gear portion can be formed by punching as well, so that it is possible to perform more rapid processing.

According to the fourth aspect, since the excess meat can be released at the time of molding, the molding can be performed with high accuracy, and the relief-shaped portion is removed in the lid removing step. It is possible to efficiently manufacture the hour wheel without affecting the above.

According to the fifth aspect, the gear portion is formed in two steps, that is, the extraction and the removal, so that the load on the mold is reduced, the durability is improved, and the gear portion is formed with high accuracy. You can

[Brief description of drawings]

FIG. 1 is schematic process diagrams (a) to (h) showing an embodiment of a timepiece wheel and wheel manufacturing method according to the invention.

FIG. 2 is a partial plan view of a plate-shaped body in the same example.

FIG. 3 is partial plan views (a) and (b) showing the planar shape of the plate-like body during the manufacturing process in the example.

FIG. 4 is a cross-sectional view showing a shape at the time of drawing in the same embodiment.

FIG. 5 is an enlarged cross-sectional view showing a shape before and after a molding step in the example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plate-like body 2 Projection part 3 Cylindrical part 3a Opening 4 Gear part 4a Tooth profile 22 Island part

Claims (6)

[Claims] 1. A plate-shaped body is repeatedly drawn to form a cylindrical protrusion with a lid, the protrusion is formed, and then the lid of the protrusion is removed to form a tubular portion. A clock wheel that is characterized by that. 2. The timepiece wheel and wheel according to claim 1, wherein the periphery of the tubular portion of the plate-shaped body is pulled out in a gear shape to form a gear portion. 3. A drawing process in which a plate-shaped body is repeatedly drawn to form a covered cylindrical protrusion, and a forming process in which the protrusion is formed to form the shape of a cylinder of a timepiece wheel. And a lid removing step of forming a tubular portion of the timepiece wheel by removing the lid portion of the protruding portion. 4. The molding process according to claim 3, wherein, in the molding step, a relief shape at the time of molding is formed in a region included in the removal portion in the lid removal process in the lid portion of the tubular portion. Manufacturing method for timepiece wheel. 5. The timepiece according to claim 3, further comprising, after the extracting step, a tooth profile removing step of forming a gear portion by removing a peripheral portion of the projecting portion of the plate-like body into a gear shape. Method for manufacturing wheel carriers. 6. The tooth profile removing step according to claim 5, wherein the step of removing the gear part from the plate-like body is performed, and the step of removing the plate-like part from the gear part is performed. And a removing step for removing the timepiece.