Mechanical timepiece and method for assembling mechanical timepiece

Abstract

The invention provides a mechanical timepiece and an assembling method of the mechanical timepiece. The mechanical timepiece is long in duration time. In a mechanical timepiece (1) in which a substantially circular movement (12) is assembled in a case (21), a spring (30) is used as a power source, a part of a barrel (15) for accommodating the spring (30) has an extension part (16) extending from the substantially circular outer periphery of the movement (12), the case (21) has a main body part (23) and a bottom part (26), and a defect part (25) for accommodating the extension part (16) is provided on the inner peripheral part (24) of the main body part (23).

Description

Technical Field

[0001] The present invention relates to a mechanical watch and an assembling method thereof. Background Art

[0002] There is known a mechanical watch that uses the mechanical energy of a mainspring to drive the hands. Patent Document 1 discloses a mechanical watch having a manual winding mechanism for winding a mainspring housed in a barrel.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-96814

[0004] However, in the mechanical watch of Patent Document 1, if a barrel with a large number of turns and a large diameter of the mainspring is used to extend the duration, the barrel will protrude from the outer periphery of the circular movement. Therefore, in order to prevent the barrel from protruding from the outer periphery of the circular movement, it is necessary to increase the diameter of the movement, and there is a problem that the inner diameter and the outer diameter of the case for housing the movement become large. Summary of the Invention

[0005] A mechanical watch is formed by assembling a substantially circular movement into a case, using a mainspring as a power source. A part of a barrel for housing the mainspring has a protruding portion that protrudes from the substantially circular outer periphery of the movement. The case has a main body portion and a bottom portion, and a defective portion for housing the protruding portion is provided on the inner peripheral portion of the main body portion.

[0006] In an assembling method of a mechanical watch, the mechanical watch is formed by assembling a substantially circular movement into a case, using a mainspring as a power source. The assembling method of the mechanical watch includes the following steps: a step of preparing the movement, a part of the outer periphery of a barrel for housing the mainspring of the movement having a protruding portion that protrudes from the outer periphery of the substantially circular movement; a step of preparing the case, a defective portion for housing the protruding portion being provided on the inner peripheral portion of the main body portion of the case; and an assembling step of assembling the movement into the main body portion of the case from a side opposite to the bottom portion of the mounting cover portion, and in the assembling step, assembling is performed in such a manner that the protruding portion is housed in the defective portion. Brief Description of the Drawings

[0007] Figure 1 It is a front view showing a schematic configuration of the mechanical watch according to the present embodiment.

[0008] Figure 2 It is a cross-sectional view showing a schematic structure of the mechanical watch according to the present embodiment.

[0009] Figure 3 It is a top view showing a structure of a bottom plate and a barrel as viewed from the back cover side.

[0010] Figure 4 It is a top view showing the structure of the bottom plate.

[0011] Figure 5 It is a top view showing the structure of the case and the barrel.

[0012] Figure 6 It is a top view showing the structure of the case and the barrel.

[0013] Figure 7 It is a top view showing the structure of the housing, the bottom plate, and the barrel.

[0014] Figure 8 It is a top view showing the structure of the housing and the bottom plate.

[0015] Description of symbols

[0016] 1: Mechanical watch; 2: Case; 3: Dial; 3A: Calendar window; 4A: Hour hand; 4B: Minute hand; 4C: Second hand; 5: Power reserve hand; 6: Date wheel; 7: Crown; 8: Stem; 9: Back cover as cover; 10: Time display; 11: Pointer shaft; 12: Movement; 13: Bottom plate; 14: Bottom plate extension; 15: Barrel; 16: Extension; 21: Case; 22: Bezel; 23: Main body; 24: Inner circumference; 25: Defective part; 26: Bottom; 27: Opening; 30: Spring; 31: Glass cover; 32: Scale ring; D: Imaginary line; D1, D2: Diameter. DETAILED DESCRIPTION

[0017] First, a wristwatch is taken as an example of a mechanical timepiece 1 according to the present embodiment. Figure 1 and Figure 2 Provide explanation.

[0018] The mechanical timepiece 1 of this embodiment is a Figure 3 The clockwork 30 in the barrel 15 shown is used as a power source, such as Figure 1 and Figure 2 As shown, the mechanical timepiece 1 has a cylindrical outer case 2, a glass cover 31, and a back cover 9 as a cover, and a disc-shaped dial 3 and a substantially circular movement 12 are arranged on the inner circumference of the outer case 2. Of the two openings of the outer case 2, the front opening is closed by the glass cover 31, and the back opening is closed by the back cover 9.

[0019] The outer case 2 is formed by fitting a bezel 22 made of ceramic or metal to a cylindrical case 21 made of metal. A disc-shaped dial 3 is arranged on the inner circumference of the bezel 22 via a circular ring 32 made of metal. A crown 7 is provided on the side of the outer case 2 at the 3 o'clock position in the clock display.

[0020] The crown 7 can be pulled out two steps from the 0-step position, which is a normal position where the crown 7 is pushed in toward the center of the mechanical timepiece 1 .

[0021] When the crown 7 is rotated at the 0-stage position, the mainspring 30 stored in the barrel 15 can be wound. The charging hand 5 provided on the dial 3 moves in conjunction with the winding of the mainspring 30.

[0022] When the crown 7 is pulled to the first position and rotated, the date wheel 6 can be moved to adjust the date. When the crown 7 is pulled to the second position, the second hand 4C stops, and when the crown 7 is rotated at the second position, the hour hand 4A and the minute hand 4B move, and the time can be adjusted.

[0023] A scale ring 32 , a time display section 10 including a dial 3 , a power reserve hand 5 indicating the duration of the mainspring 30 , and a movement 12 are housed in a space surrounded by the outer case 2 , the back cover 9 , and the glass cover 31 .

[0024] The scale ring 32 includes a flat plate portion whose outer peripheral end contacts the inner peripheral surface of the bezel 22 and whose one surface is parallel to the glass cover 31, and an inclined portion which is inclined toward the dial 3. The scale ring 32 is annular in plan view and mortar-shaped in cross-sectional view.

[0025] The time display unit 10 is driven by the movement 12 to display the time, and has an hour hand 4A, a minute hand 4B and a second hand 4C as pointers between the dial 3 and the glass cover 31, and the time display unit 10 is arranged on the inner side of the scale ring 32. In addition, a small calendar window 3A is provided on the dial 3, and the date wheel 6 can be visually viewed from the small calendar window 3A.

[0026] The movement 12 is arranged between the dial 3 and the back cover 9, and is driven by a stepping motor and a gear train. Figure 1 The hour hand 4A, minute hand 4B and second hand 4C shown are driven. In addition, the hour hand 4A, minute hand 4B and second hand 4C are mounted on a pointer shaft 11 located in the center of the plane of the dial 3, and a stem 8 is mounted on the movement 12, and a crown 7 is mounted on the end of the stem 8.

[0027] Next, refer to Figures 3 to 8 The structures of the bottom plate 13 of the movement 12 , the barrel 15 , and the case 21 accommodating the movement 12 will be described.

[0028] in addition, Figure 3 , Figure 5 and Figure 7 This is a picture viewed from the back cover side. Figure 4 , Figure 6 and Figure 8 This is a picture viewed from the dial side.

[0029] like Figure 3As shown, the movement 12 having a base plate 13 and a barrel 15 is substantially circular with a diameter D1 shown by the imaginary line D.

[0030] The barrel 15 fixed to the base plate 13 and housing the mainspring 30 is circular in shape, as Figure 3 shown, and a part thereof has a protruding portion 16 that protrudes from the outer periphery of the substantially circular movement 12. Specifically, the barrel 15 has a protruding portion 16 that protrudes from the imaginary line D representing the outer periphery of the substantially circular movement 12.

[0031] The base plate 13 fixes the barrel 15. As Figure 3 and Figure 4 shown, the base plate 13 has a base plate protruding portion 14 that is the same as the protruding portion 16 of the barrel 15 and that protrudes from the imaginary line D representing the outer periphery of the substantially circular movement 12. By making the base plate protruding portion 14 of the base plate 13 the same shape as the protruding portion 16 of the barrel 15, the protruding portion 16 of the barrel 15 can be protected during assembly and the like.

[0032] The case 21 has a main body portion 23 and a bottom portion 26. As Figure 6 shown, a cutout portion 25 for housing the protruding portion 16 of the barrel 15 is provided in the inner peripheral portion 24 of the main body portion 23. Therefore, without increasing the outer peripheral size of the case 21, the barrel 15 with a larger number of turns and a larger diameter of the mainspring 30 can be housed in the main body portion 23 of the case 21 in order to extend the duration. In addition, as Figure 8 shown, the cutout portion 25 also houses the base plate protruding portion 14 of the base plate 13.

[0033] The cutout portion 25 is provided between 11 o'clock and 1 o'clock centered on 12 o'clock in the longitudinal clock display perpendicular to the width direction, or between 5 o'clock and 7 o'clock centered on 6 o'clock in the clock display. At this position, the wall thickness of the main body portion 23 is thicker than that at other positions. Therefore, by providing the cutout portion 25, a reduction in the strength of the case 21 can be prevented.

[0034] As Figure 5 and Figure 7 shown, the bottom portion 26 of the case 21 has an opening portion 27 for mounting the circular back cover 9, and the diameter D2 of the opening portion 27 is smaller than the diameter D1 of the substantially circular movement 12. Therefore, during assembly, the movement 12 is assembled by being inserted into the main body portion 23 of the case 21 from the dial 3 side.

[0035] As described above, in the mechanical timepiece 1 of the present embodiment, the cutout portion 25 for housing the protruding portion 16 of the barrel 15 is provided in the inner peripheral portion 24 of the main body portion 23 of the case 21. Therefore, without increasing the outer peripheral size of the case 21, the barrel 15 with a larger number of turns and a larger diameter of the mainspring 30 can be housed in the main body portion 23 of the case 21 in order to extend the duration. Therefore, a mechanical timepiece 1 with a longer duration can be obtained.

[0036] Next, the assembly method of the mechanical clock 1 of the present embodiment will be described.

[0037] The assembly method of the present embodiment is an assembly method of the mechanical clock 1 that assembles the substantially circular movement 12 into the case 21 and uses the mainspring 30 as a power source. This assembly method includes a movement preparation process, a case preparation process, and an assembly process.

[0038] 1. Movement preparation process

[0039] In the movement preparation process, the movement 12 is prepared. A part of the outer periphery of the barrel 15 that houses the mainspring 30 of the movement 12 has a protruding portion 16 that protrudes from the outer periphery of the substantially circular movement 12.

[0040] 2. Case preparation process

[0041] In the case preparation process, the case 21 is prepared. A defective portion 25 for housing the protruding portion 16 is provided on the inner peripheral portion 24 of the main body portion 23 of the case 21.

[0042] 3. Assembly process

[0043] In the assembly process, since the diameter D2 of the opening 27 provided at the bottom 26 of the case 21 for installing the back cover 9 as a cover portion is smaller than the diameter D1 of the substantially circular movement 12, the movement 12 is assembled into the main body portion 23 of the case 21 from the side opposite to the bottom 26 where the back cover 9 is installed. That is, the side opposite to the back cover 9 refers to the front side where the dial 3 is located. The diameter of this dial 3 is usually larger than the diameter of the movement 12. Therefore, it can be easily assembled by inserting it from the front side. In addition, from the viewpoint of waterproofness, the area of the back cover 9 cannot be increased beyond a certain value. Therefore, the opening 27 at the bottom 26 of the case 21 cannot be increased either. As a result, since the movement 12 cannot be inserted through the opening on the back cover 9 side, it is structured to be inserted from the dial 3 side with a larger opening. In addition, in the assembly process, the protruding portion 16 is assembled into the defective portion 25 so as to be housed therein.

[0044] Through the above processes, a mechanical clock 1 is assembled in which the protruding portion 16 of the barrel 15 is housed in the defective portion 25 provided on the inner peripheral portion 24 of the main body portion 23 of the case 21.

[0045] As described above, in the assembling method of the present embodiment, by assembling the movement 12 from the side opposite to the bottom portion 26 where the back cover 9 is installed to the main body portion 23 of the housing 21, the protruding portion 16 of the barrel 15 can be accommodated in the defective portion 25 of the housing 21. Therefore, without increasing the outer peripheral size of the housing 21, the barrel 15 with a larger number of turns and a larger diameter of the mainspring 30 can be accommodated in the main body portion 23 of the housing 21 in order to extend the duration, and the mechanical watch 1 with a longer duration can be assembled.

Claims

1. A mechanical clock, which is formed by assembling a substantially circular movement into a case, and uses a mainspring as a power source. A part of the barrel housing the mainspring has a protruding portion extending from the outer periphery of the substantially circular movement of the movement. The case has a main body portion and a bottom portion. A missing portion for housing the protruding portion is provided on the inner peripheral portion of the main body portion of the case.

2. The mechanical clock according to claim 1, wherein an opening for mounting a circular cover portion is provided in the bottom portion of the case, and the diameter of the opening is smaller than the diameter of the substantially circular movement.

3. The mechanical clock according to claim 1 or 2, wherein the bottom plate fixing the barrel has a bottom plate protruding portion the same as the protruding portion of the barrel.

4. The mechanical clock according to claim 1 or 2, wherein the missing portion is provided between 11 o'clock and 1 o'clock centered on 12 o'clock in the longitudinal clock display perpendicular to the width direction, or is provided between 5 o'clock and 7 o'clock centered on 6 o'clock in the longitudinal clock display perpendicular to the width direction.

5. An assembling method of a mechanical clock, the mechanical clock is formed by assembling a substantially circular movement into a case, and uses a mainspring as a power source, the assembling method of the mechanical clock has the following steps: a step of preparing the movement, a part of the outer periphery of the barrel housing the mainspring of the movement has a protruding portion extending from the outer periphery of the substantially circular movement; a step of preparing the case, a missing portion for housing the protruding portion is provided on the inner peripheral portion of the main body portion of the case; and an assembling step of assembling the movement into the main body portion of the case from the side opposite to the bottom portion where the cover portion is mounted, in the assembling step, the assembling is performed in such a manner that the protruding portion is housed in the missing portion.

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