Crown for wristwatch, pipe for crown, wristwatch structure, and method for manufacturing wristwatch structure

Abstract

A crown 10 for a wristwatch comprises a shaft part 11 extending in an X direction, a head 12 provided to the shaft part 11, an identifier 13 provided to a surface 12B of the head 12, a lateral extension part 14 extending to a reverse surface 12A on a lateral side of the head 12, and a female screw 18 provided to an inner peripheral surface of the lateral extension part 14. A crown pipe 20 is provided with a cylinder part 21, and a male screw 22 provided to the cylinder part 21. The female screw 18 can be helically engaged with the male screw 22 of the crown pipe 20. The female screw 18 and the male screw 22 are six-thread screws.

Description

Wristwatch crown, crown pipe, wristwatch structure, and method of manufacturing the wristwatch structure

[0001] The present invention relates to a wristwatch crown, a crown pipe, a wristwatch structure, and a method for manufacturing the wristwatch structure.

[0002] A watch crown is attached to a watch so as to improve the water resistance of the watch's winding stem, i.e., its control system (see, for example, Patent Document 1). The watch crown can be set in either a loosened position, which allows the watch to be wound and set to the correct time, or a screwed-in position, which screws the crown into a pipe driven into an intermediate member of the watch case, locking it in place and compressing the sealing gasket, improving the watch's water resistance. When the watch is normally used, the watch crown is in the screwed-in position.

[0003] However, a watch crown may have a trademark or design on its surface. When a watch crown bearing such a trademark or design is attached to a watch case, the trademark or design may not be oriented correctly. This situation detracts from the aesthetic appearance of the watch case and, ultimately, the watch itself, and is unacceptable when the watch is a high-quality, luxury product.

[0004] In the invention described in Patent Document 1, in order to properly orient the watch crown, a thread is provided on the pipe into which the watch crown screws so that it can be screwed into a hole in the watch case, and a nut for positioning the pipe is placed on the watch case.The pipe is then screwed into the watch case, and once the watch crown is properly oriented, it is positioned with the nut from inside the watch case.

[0005] Special Publication No. 2003-5157502

[0006] However, in Patent Document 1, screws or positioning nuts must be provided on the pipe or watch case to ensure that the orientation of the trademark or design on the watch crown is correct. The inside of the watch case is densely packed with transmission parts such as the rotor, gears, and levers that make up the movement, and providing a separate screw or positioning nut on the watch case to ensure that the orientation of the watch crown is correct would lead to a decrease in manufacturing quality and an increase in manufacturing costs.

[0007] Therefore, the present disclosure aims to provide a wristwatch crown with a simple and economical structure that ensures that the trademark or design is oriented correctly when attached to a wristwatch case. It also aims to provide a crown pipe, a wristwatch structure, and a method for manufacturing the wristwatch structure that are compatible with this wristwatch crown.

[0008] The wristwatch crown of the present disclosure comprises a shaft portion, a head provided at the tip of the shaft portion, an identifier provided on the surface of the head, a lateral extension portion extending to the back side on the side of the head, and a female thread provided on the inner surface of the lateral extension portion, wherein the female thread is a multiple-start thread.

[0009] The crown pipe of the present disclosure preferably comprises a pipe into which the stem of a wristwatch crown is inserted, and a male thread provided on the outer periphery of the pipe, the male thread being capable of being threaded into the female thread.

[0010] The wristwatch structure disclosed herein is a wristwatch structure comprising a wristwatch crown, a crown pipe, and a wristwatch case capable of housing a movement, wherein the wristwatch case is formed with a pipe mounting hole into which the crown pipe can be inserted, and when the crown pipe is inserted into the hole, the male screw is located in the external space of the case.

[0011] It is preferable that the watch comprises a winding stem having one end engaged with the movement and the other end inserted into the hollow portion of the crown pipe, and a biasing member arranged between the winding stem and the watch crown, the biasing member biasing the watch crown towards the external space of the watch case.

[0012] The manufacturing method of the wristwatch structure disclosed herein comprises a pipe mounting step of mounting a crown pipe to a wristwatch case capable of accommodating a movement, a temporary mounting step of mounting a wristwatch crown to the crown pipe, a detection step of detecting the difference between the direction of the head identifier when the movement is in a usable state and a reference direction, and an mounting step of mounting the wristwatch crown to the crown pipe, wherein the screwing start position in the mounting step is a position that offsets the difference detected in the detection step based on the screwing start position in the temporary mounting step.

[0013] According to the present disclosure, it is possible to provide a wristwatch crown with a simple and economical structure that ensures that the trademark or design is oriented correctly when attached to a wristwatch case. Furthermore, according to the present disclosure, it is possible to provide a crown pipe, a wristwatch structure, and a method for manufacturing a wristwatch structure that are compatible with this wristwatch crown.

[0014] 1 is a cross-sectional view showing an overview of a wristwatch structure; 2 is an exploded cross-sectional view showing an overview of a wristwatch structure; 3 is a plan view showing an overview of a crown pipe; 4 is a left side view, a front view, a right side view, a back view, and a bottom view showing an overview of a crown pipe, respectively; 5 is a perspective view showing an overview of a wristwatch crown; 6 is a plan view showing an overview of a wristwatch crown; 7 is a front view and a bottom view showing an overview of a wristwatch crown; 8 is a flow chart showing an overview of a manufacturing method for a wristwatch structure; 9 is a plan view showing an overview of the start position of screwing in the crown pipe when starting the temporary attachment step, and the orientation of the identifier on the wristwatch crown (direction A); 10 is an explanatory diagram showing an overview of the difference φ1 between the orientation of the wristwatch crown when starting the temporary attachment step (direction Z) and the orientation of the wristwatch crown in the detection step (direction A). (C) is an explanatory diagram showing an outline of the difference φ1 between the orientation of the watch crown when the temporary attachment step begins (direction Z) and the orientation of the watch crown when the attachment step begins (direction A). (A) is a plan view showing an outline of the start position of screwing in the crown pipe and the orientation of the identifier on the watch crown when the temporary attachment step begins (direction A). (B) is an explanatory diagram showing an outline of the difference φ1 between the orientation of the watch crown when the temporary attachment step begins (direction Z) and the orientation of the watch crown in the detection step (direction A). (C) is an explanatory diagram showing an outline of the difference φ1 between the orientation of the watch crown when the temporary attachment step begins (direction Z) and the orientation of the watch crown when the attachment step begins (direction A).

[0015] As shown in FIGS. 1 and 2, the wristwatch structure 2 comprises a wristwatch crown 10, a crown pipe 20, a wristwatch case 30, an O-ring 40, a winding stem 50, and a biasing member 60.

[0016] Hereinafter, for convenience of explanation, an arbitrary direction on a horizontal plane will be referred to as the X direction, a direction on the horizontal plane perpendicular to the X direction will be referred to as the Y direction, and a direction perpendicular to the X and Y directions will be referred to as the Z direction.

[0017] The watch case 30 is formed in the shape of a flat rectangular parallelepiped with sides in the X, Y, and Z directions, and the watch face is visible on the front surface 30F, which also has sides in the X and Y directions. The watch case 30 has an internal space 30K capable of accommodating a movement M (internal mechanism).

[0018] A pipe mounting hole 30X for mounting the crown pipe 20 is provided on a side surface 30S of the watch case 30, which has sides in the X and Z directions. The pipe mounting hole 30X extends in the X direction. The pipe mounting hole 30X connects the external space 30G of the watch case 30 with the internal space 30K.

[0019] As shown in FIGS. 2 and 3, the crown pipe 20 includes a cylindrical portion 21 and a male screw 22 provided on the cylindrical portion 21 .

[0020] The cylindrical portion 21 extends in the X direction, and one end thereof is a small diameter portion 21A which functions as an attachment portion to the watch case 30, and the other end thereof is a large diameter portion 21B which has a larger outer diameter than the small diameter portion 21A and functions as an attachment portion to the watch crown 10. A male thread 22 is provided on the outer periphery of the large diameter portion 21B.

[0021] The male thread 22 is a six-start thread. When the crown pipe 20 is attached to the watch case 30, the male thread 22 is exposed to the external space 30G of the watch case 30 (FIG. 1).

[0022] As shown in Figures 2, 4, and 5, the wristwatch crown 10 comprises a shaft portion 11 extending in the X direction, a head 12 provided on the shaft portion 11, an identifier 13 provided on the surface 12B of the head 12, a lateral extension portion 14 extending to the back surface 12A on the side of the head 12, and a female thread 18 provided on the inner surface of the lateral extension portion 14.

[0023] The stem 11 has a shape that allows it to be inserted into the hollow portion 21X of the tubular portion 21 of the crown pipe 20. One end portion 11A of the stem 11 is formed with a biasing member accommodating hole 11X that can accommodate the biasing member 60. The biasing member accommodating hole 11X extends in the X direction. The other end portion 11B of the stem 11 is fixed to the head 12 by caulking, welding, or the like.

[0024] The head 12 is formed in a disk shape, extending radially from the X direction. An identifier 13 such as a logo mark is provided on a surface 12B (the other side) of the head 12. The identifier 13 is fixedly displayed on the surface 12B of the head 12 by engraving, burning, or the like.

[0025] The lateral extension 14 extends in the X direction from the back surface 12A of the head 12, is cylindrical, and is arranged coaxially with the head 12. A female thread 18 is formed on the inner peripheral surface of the lateral extension 14. The female thread 18 can be threadedly engaged with the male thread 22 of the crown pipe 20. The female thread 18 is a six-start thread. On the outer peripheral surface of the lateral extension 14, knob protrusions 19 are arranged at predetermined intervals in the circumferential direction.

[0026] The O-ring 40 is attached to the O-ring recess 11R of the shaft portion 11, and is intended to improve the airtightness and waterproofness of the gap between the shaft portion 11 of the watch crown 10 and the crown pipe 20. The O-ring recess 11R is a groove provided in the middle of the shaft portion 11 and extending in the circumferential direction, and is located closer to one end than the lateral extension portion 14 in the X direction.

[0027] 1 and 2, the winding stem 50 transmits the relative position of the head 12 with respect to the crown pipe 20 to the movement M. The winding stem 50 extends in the X direction, with one end 50A of the winding stem 50 engaging with the movement M and the other end 50B of the winding stem 50 inserted into the hollow portion of the crown pipe 20. The other end 50B is shaped so as to be able to engage with the biasing member 60.

[0028] The urging member 60 is a coil spring or the like, extends in the X direction, and is housed in a urging member housing hole 11X formed in one end 11A of the shaft 11. One end 60A of the urging member 60 is fixed to or engaged with the winding stem 50. The urging member 60 urges the shaft 11 of the watch crown 10 toward the head 12. The other end 60B of the urging member 60 may be fixed to or engaged with the wall surface of the urging member housing hole 11X, or may abut against the wall surface of the urging member housing hole 11X. The urging member 60 can be a coil spring or the like.

[0029] When the watch crown 10 is screwed into the crown pipe 20 (threaded state, Figure 1), the movement M is in a state in which it keeps time (normal state). Furthermore, the O-ring 40 ensures a certain level of airtightness and waterproofness in the gap between the stem 11 and the crown pipe 20. On the other hand, when the watch crown 10 is separated from the crown pipe 20 (threaded retracted state), the movement M is in a state in which settings such as the current time can be changed (setting change state). In this way, the movement M can be switched between the normal state and the setting change state depending on the degree to which the watch crown 10 is screwed into the crown pipe 20.

[0030] Next, a method for manufacturing the wristwatch structure 2 will be described.

[0031] As shown in FIG. 6 , the manufacturing method 100 of a wristwatch structure includes a movement mounting step 110 , a pipe mounting step 120 , a crown mounting step 130 , a temporary mounting step 140 , a detection step 150 , and a mounting step 160 .

[0032] (Movement Mounting Step) In the movement mounting step 110, the movement M is mounted in the internal space 30K of the watch case 30 placed on a flat surface.

[0033] (Pipe Attachment Step) In the pipe attachment step 120, the crown pipe 20 is attached by welding, brazing, or the like to the pipe attachment hole 30X of the watch case 30. Note that in the pipe attachment step 120, a female thread may be provided in the pipe attachment hole 30X, and a male thread may be provided on the outer circumferential surface of the crown pipe 20, so that the crown pipe 20 is screwed into the pipe attachment hole 30X.

[0034] (Crown Attaching Step) In the crown attaching step 130, the watch crown 10, the winding stem 50, and the biasing member 60 are assembled. In the crown attaching step 130, first, the biasing member 60 is inserted into the biasing member accommodating hole 11X. After that, one end 60A of the biasing member 60 is fixed to or engaged with the other end 50B of the winding stem 50. This allows the winding stem 50 to move in the X direction and couples with the watch crown 10. Furthermore, the biasing member 60 is ready to bias the stem 11 toward the head 12.

[0035] In addition, in the crown attachment step 130, after one side end 60A of the urging member 60 is fixed or engaged with the other side end 50B of the winding stem 50, the urging member 60 may be inserted into the urging member accommodating hole 11X.

[0036] (Temporary installation step) In the temporary installation step 140, the watch crown 10 (Figure 7 (A)) is oriented so that the orientation of the identifier 13 (direction A in the figure) is the reference direction (e.g., direction Z), and is screwed into the crown pipe 20 fixed to the watch case 30 until the movement M is ready for use.

[0037] (Detection Step) In detection step 150, the difference φ1 between the orientation of the identifier 13 of the wristwatch crown 10 when it is fully screwed into the crown pipe 20 and the reference direction is detected. Here, with the surface 12 (identifier 13) of the head 12 facing directly, the screwing direction (clockwise) is defined as +, and the loosening direction (counterclockwise) is defined as -.

[0038] (Attachment Step) If the difference φ1 detected in detection step 150 is a positive value (FIG. 7(B)), after loosening the watch crown 10 from the crown pipe 20, start screwing the watch crown 10 into the crown pipe 20 (FIG. 7(C)) at a point close to the direction opposite the screwing direction (-φ1±30°) that is φ1 away from the orientation of the identifier 13 (i.e., the Z direction) at the start of temporary attachment step 140. This makes it possible to minimize the difference between the orientation of the identifier 13 of the head 12 when screwed into the crown pipe 20 and the reference direction.

[0039] If the difference φ1 detected in detection step 150 is a negative value (FIG. 8(B)), after loosening the watch crown 10 from the crown pipe 20, start screwing the watch crown 10 into the crown pipe 20 at a point (FIG. 8(C)) that is closer to the screwing direction (+φ1±30°) by φ1 from the orientation of the identifier 13 (i.e., the Z direction) at the start of temporary attachment step 140. This makes it possible to minimize the difference between the orientation of the identifier 13 of the head 12 when screwed into the crown pipe 20 and the reference direction.

[0040] Because the female thread 18 and male thread 22 are six-start threads, the screwing start positions 20F of the watch crown 10 on the crown pipe 20 are aligned at 60° intervals in the circumferential direction (FIG. 3). Therefore, by performing the detection step 150 and temporary attachment step 140, it is possible to set the screwing start position in the attachment step 160 to a position that offsets the difference detected in the detection step 150, based on the screwing start position in the temporary attachment step 140. This makes it possible to minimize the difference between the direction of the identifier 13 on the head 12 and the reference direction.

[0041] Furthermore, the screwing operation of the wristwatch crown 10 is performed by a person, such as an assembly worker or a user. Therefore, screwing in a wristwatch crown 10 with a relatively small diameter (for example, a diameter of 3 mm or more and 10 mm or less) is difficult. Furthermore, screwing in a wristwatch crown 10 while it is biased by the biasing member 60 is even more difficult. If the female thread 18 and male thread 22 are six-start threads as in this case, then screwing the wristwatch crown 10 into the crown pipe 20 only requires a small amount of threading.

[0042] In the above embodiment, the male thread 22 and the female thread 18 are six-start threads, but the present disclosure is not limited to this, and other start threads such as two-start threads, three-start threads, and eight-start threads may also be used.

[0043] It should be noted that the present disclosure is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and scope of the present disclosure.

[0044] DESCRIPTION OF SYMBOLS 2 Wristwatch structure 10 Wristwatch crown 11 Base portion 11R O-ring recess 11X Urging member accommodating hole 12 Head 13 Identifier 14 Lateral extension portion 18 Female thread 19 Protrusion 20 Crown pipe 20F Screwing start position 21 Cylinder portion 22 Male thread 30 Wristwatch case 30K Internal space 30F Front 30G External space 30S Side 30X Pipe mounting hole 40 O-ring 50 Winding stem 60 Urging member 100 Manufacturing method of wristwatch structure 110 Movement mounting step 120 Pipe mounting step 130 Crown mounting step 140 Temporary mounting step 150 Detection step 160 Mounting step

Claims

1. A wristwatch crown comprising: a shaft portion; a head provided at the tip of the shaft portion; an identifier provided on the surface of the head; a lateral extension portion extending to the back side of the head; and a female thread provided on the inner surface of the lateral extension portion, wherein the female thread is a multiple start thread.

2. A crown pipe comprising: a pipe into which the stem of the wristwatch crown according to claim 1 is inserted; and a male thread provided on the outer periphery of said pipe, said male thread being capable of being screwed into said female thread.

3. A wristwatch structure comprising: a wristwatch crown as claimed in claim 1; a crown pipe as claimed in claim 2; and a wristwatch case capable of housing a movement, wherein a pipe mounting hole into which said crown pipe can be inserted is formed in said wristwatch case, and when said crown pipe is inserted into said hole, said male screw is located in the external space of said case.

4. A wristwatch structure as described in claim 3, comprising: a winding stem, one end of which engages with the movement and the other end of which is inserted into the hollow portion of the crown pipe; and a biasing member disposed between the winding stem and the wristwatch crown, said biasing member biasing the wristwatch crown towards the external space of the wristwatch case.

5. A method for manufacturing a wristwatch structure, comprising: a pipe mounting step of mounting the crown pipe described in claim 2 to a wristwatch case capable of accommodating a movement; a temporary mounting step of mounting the wristwatch crown described in claim 1 to the crown pipe; a detection step of detecting the difference between the direction of the head identifier when the movement is in a usable state and a reference direction; and an mounting step of mounting the wristwatch crown to the crown pipe, wherein the screwing start position in the mounting step is a position that offsets the difference detected in the detection step based on the screwing start position in the temporary mounting step.

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