JP7773019B2 - Exterior materials and watches - Google Patents

Description

This invention relates to exterior components used in electronic devices such as wristwatches and personal digital assistants, and to watches equipped with such components.

For example, in the exterior components of wristwatches, as described in Patent Document 1, a structure is known in which carbon fiber is used as a reinforcing material, this carbon fiber is layered on both the front and back surfaces to form a carbon fiber reinforced resin sheet, and a thermosetting resin is applied to the front and back surfaces of this carbon fiber reinforced resin sheet.

Japanese Patent Application Laid-Open No. 2005-114495

The exterior components of such wristwatches are constructed by applying thermosetting resin to the front and back surfaces of a carbon fiber reinforced resin sheet made by laminating carbon fiber in both directions. While this can reduce weight, it does not provide sufficient strength and is unable to ensure impact resistance.

The problem this invention aims to solve is to provide an exterior component that can increase strength and improve impact resistance, and a watch equipped with the same.

The present invention is an exterior member characterized by comprising an exterior main body and a tubular member that is a second fiber-reinforced resin sheet provided on the exterior main body and shaped like a tube .

This invention makes it possible to increase strength and improve impact resistance.

1 is an enlarged perspective view showing an embodiment of a wristwatch to which the present invention is applied. FIG. 2 is an exploded, enlarged perspective view of the wristwatch case shown in FIG. 1 . FIG. 3 is an enlarged perspective view showing an exterior member of the wristwatch case shown in FIG. 2 . 4 is an enlarged perspective view showing the fiber direction of a third fiber-reinforced resin sheet provided on each surface of a protrusion and a band attachment portion in the exterior member shown in FIG. 3 . FIG. 4 is an enlarged side view of the exterior member shown in FIG. 3 as viewed from the 3 o'clock side. FIG. 2 is an enlarged cross-sectional view of the protrusion on the 9 o'clock side of the watch case shown in FIG. 1, taken along the line AA. 5 is an enlarged cross-sectional view of the protrusion on the 9 o'clock side of the exterior member shown in FIG. 4, taken along the line BB. 5 is an enlarged cross-sectional view of the band attachment portion on the 6 o'clock side of the exterior member shown in FIG. 4, taken along the CC arrows.

An embodiment in which the present invention is applied to a wristwatch will be described below with reference to FIGS.
As shown in Figure 1, this wristwatch has a wristwatch case 1. Band attachment sections 2, to which a watch band (not shown) is attached, protrude from the 12 o'clock and 6 o'clock sides of this wristwatch case 1. Furthermore, switch sections 3 are provided in five locations on the 2 o'clock, 3 o'clock, 4 o'clock, 8 o'clock, and 10 o'clock sides of this wristwatch case 1.

As shown in Figures 1 and 2, this wristwatch case 1 comprises a lower case 4, an upper case 5, and an exterior member 6. The lower case 4, in which a watch module (not shown) is placed, is formed into a cylindrical shape with a bottom made of metal such as stainless steel or hard synthetic resin. Switch mounting holes 4a, into which the switch unit 3 is attached, are provided in each of the side walls of the lower case 4 at the 2 o'clock, 3 o'clock, 4 o'clock, 8 o'clock, and 10 o'clock sides.

As shown in Figures 1 and 2, the upper case 5 has a watch crystal 7 attached to its inner surface via a crystal packing 7a (see Figure 6), and is formed in a roughly ring shape from a metal such as stainless steel or a hard synthetic resin. The upper case 5 is configured to be placed on top of the lower case 4, with a waterproof ring 5a (see Figure 6) placed between its underside and the top of the lower case 4.

In this case, as shown in Figures 1 and 2, screw mounting portions 8 are provided on each of the outer surfaces of the upper case 5 at the 1 o'clock, 5 o'clock, 7 o'clock, and 11 o'clock sides. These screw mounting portions 8 include a semicircular groove 8a provided in the vertical direction on the outer surface of the upper case 5, and a disk portion 8b provided below this groove 8a and protruding in a semicircular shape from within the groove 8a, with a screw insertion hole 8c provided in the center of the disk portion 8b.

As a result, as shown in Figures 1 and 2, when the threaded portion 9a of the screw member 9 is inserted into the screw insertion hole 8c of the screw mounting portion 8 and threaded into the screw hole 11a in the exterior member 6 (described below), the upper case 5 is pressed against the exterior member 6 by the screw head 9b, thereby covering the top of the lower case 4 and attaching it to the top of the exterior member 6.

As shown in Figures 1 and 2, the exterior member 6 is inserted from above into the lower case 4, and includes a roughly ring-shaped exterior body 10 that is positioned around the outer periphery of the lower case 4. Switch insertion holes 10a, into which the switch heads of the switch unit 3 are placed, are provided in the side walls of the exterior body 10 on the 2 o'clock, 3 o'clock, 4 o'clock, 8 o'clock, and 10 o'clock sides, corresponding to the multiple switch mounting holes 4a provided in the lower case 4.

Furthermore, as shown in Figures 2 to 4 and 6, anti-slip recesses 10b are provided on the inner peripheral surface of the exterior body 10 at the 3 o'clock and 9 o'clock sides, opening onto the inner peripheral surface and upper end surface. As shown in Figure 6, when the engaging protrusions 4b provided on the 3 o'clock and 9 o'clock sides of the outer peripheral surface of the lower case 4 are inserted from above, the lower ends of the engaging protrusions 4b of the lower case 4 abut against and engage the lower ends of the anti-slip recesses 10b, preventing the lower case 4 from slipping out below the exterior member 6.

As shown in Figures 1 to 3, the top surface of this exterior body 10 is provided with mounting recesses 11 at the 1 o'clock, 5 o'clock, 7 o'clock, and 11 o'clock positions, into which the disc portion 8b of the screw mounting portion 8 of the upper case 5 is positioned. These mounting recesses 11 are each provided with a screw hole 11a into which the threaded portion 9a of the screw member 9 screws into. As a result, when the lower case 4 is positioned within the exterior body 10 of the exterior member 6 and the upper case 5 is placed on the exterior member 6, covering the top of the lower case 4, the disc portion 8b of the screw mounting portion 8 of the upper case 5 is positioned within the mounting recesses 11 of the exterior member 6.

That is, as shown in Figures 1 to 3, the exterior member 6 is configured so that the screw insertion hole 8c provided in the disc portion 8b of the screw mounting portion 8 of the upper case 5 corresponds coaxially to the screw hole 11a in the mounting recess 11 of the exterior body 10, and in this state the threaded portion 9a of the screw member 9 threads from the screw insertion hole 8c in the disc portion 8b into the screw hole 11a in the mounting recess 11, allowing the screw head 9b to press the upper case 5 onto the exterior body 10.

In this case, as shown in Figures 1 to 3, the screw member 9 is configured so that when the screw portion 9a is threaded through the screw insertion hole 8c and into the screw hole 11a and tightened, the screw head 9b presses the disk portion 8b of the screw mounting portion 8 of the upper case 5 into the mounting recess 11 of the exterior member 6. As a result, the lower case 4 is pressed down by the upper case 5 and fixed within the exterior member 6, with the lower ends of the engagement protrusions 4b abutting and engaging the lower ends of the retaining recesses 10b of the exterior body 10, as shown in Figure 6.

As shown in Figures 1 and 2, protrusions 12 protrude laterally from the 3 o'clock and 9 o'clock positions on the outer periphery of the exterior body 10. In this case, the protrusion 12 on the 3 o'clock side protects the switch head of the switch unit 3 and is located between the 2 o'clock and 4 o'clock sides. A switch insertion hole 10a is provided in the center of this 3 o'clock side protrusion 12, into which the switch head of the switch unit 3 is positioned. The protrusion 12 on the 9 o'clock side is located between the 8 o'clock and 10 o'clock sides.

As shown in Figures 2 to 5, band attachment sections 2, which are protrusions and attachment protrusions, are provided on the 12 o'clock and 6 o'clock sides of the exterior body 10 and protrude outward. A watch band (not shown) is attached to these band attachment sections 2, and each has a band attachment hole 2a formed in a direction along the outer periphery of the exterior body 10. In other words, although not shown, these band attachment sections 2 are configured so that a watch band can be attached by inserting a connecting member such as a spring bar provided at the end of the watch band into the band attachment hole 2a.

As shown in Figures 4 and 5, the exterior body 10, excluding the band attachment section 2, has a structure in which first fiber-reinforced resin sheets 13 are stacked one on top of the other. In other words, this first fiber-reinforced resin sheet 13 is a sheet in which carbon fibers or glass fibers are arranged and hardened with synthetic resin.

In this case, as shown in Figures 4 and 5, the first fiber-reinforced resin sheet 13 may be made by laminating only sheets with aligned carbon fibers, or by laminating only sheets with aligned glass fibers and coloring each layer, or by laminating a combination of sheets with aligned carbon fibers and sheets with aligned glass fibers. In other words, the first fiber-reinforced resin sheet 13 with aligned carbon fibers will be black, and the first fiber-reinforced resin sheet 13 with aligned glass fibers and colored can be colored.

Furthermore, as shown in Figures 4 and 5, when the first fiber-reinforced resin sheets 13 are stacked one on top of the other, it is desirable to stack them so that the fiber arrangement directions alternately cross in order to ensure the strength of the exterior body 10. Furthermore, the synthetic resin that solidifies the fibers in the first fiber-reinforced resin sheets 13 includes polycarbonate resin, ABS resin, epoxy resin, polyether resin, etc.

As shown in Figures 4 and 5, the exterior body 10 is formed into a strong, generally ring-shaped structure by stacking first fiber-reinforced resin sheets 13 one above the other and bonding the synthetic resin of each sheet together using thermocompression bonding. While the exterior body 10 is formed in a generally ring shape, the outer and inner surfaces are machined to form the desired shape.

In this case, as shown in Figures 6 and 7, the protrusions 12 on the 3 o'clock and 9 o'clock sides of the exterior body 10 have a structure in which first fiber-reinforced resin sheets 13 are stacked one above the other, similar to the exterior body 10. Furthermore, as shown in Figures 3 to 5 and 8, the band attachment sections 2 on the 12 o'clock and 6 o'clock sides of the exterior body 10 each have a reinforcing section 15, which is a cylindrical member formed by wrapping a second fiber-reinforced resin sheet 14 around it in a cylindrical shape.

That is, as shown in Figures 3 to 5 and 8, the reinforcing portion 15 of the band attachment portion 2 is formed in a cylindrical shape by concentrically wrapping the second fiber-reinforced resin sheet 14 around the band attachment hole 2a, which is provided in a direction along the outer periphery of the exterior body 10, and laminating it in multiple layers. In this case, the second fiber-reinforced resin sheet 14 may be a glass-fiber-reinforced resin sheet with aligned glass fibers, but is preferably a carbon-fiber-reinforced resin sheet with aligned carbon fibers.

As shown in Figures 3 to 5 and 8, the second fiber-reinforced resin sheet 14 is formed so that the carbon fiber direction when wrapped around the tube is either perpendicular or transverse to the axial direction of the band attachment hole 2a, which is the axial direction of the tube. In other words, the second fiber-reinforced resin sheet 14 is formed so that when the watch band (not shown) attached to the band attachment portion 2 is pulled in its longitudinal direction, the fibers of the second fiber-reinforced resin sheet 14 are aligned in a direction that receives a tensile force.

In this case, as shown in Figures 3 to 5 and 8, the second fiber-reinforced resin sheet 14 is wound concentrically, stacked and wound so that the fiber arrangement directions alternately cross, resulting in a cylindrical shape. Alternatively, the second fiber-reinforced resin sheet 14 is wound so that the fiber arrangement direction is perpendicular to the axial direction of the band mounting hole 2a, which is the cylindrical axis direction, resulting in a cylindrical shape.

As shown in Figures 4, 5, and 8, the band attachment portion 2 also includes a shaping portion 16 that shapes the entire band attachment portion 2 when the reinforcing portion 15 is attached to the exterior body 10. The shaping portions 16 are provided to correspond to the side and top sides of the cylindrical reinforcing portion 15. That is, the portions of the shaping portion 16 that correspond to the side sides of the reinforcing portion 15 have a structure in which first fiber-reinforced resin sheets 13 are laminated vertically, similar to the exterior body 10.

As shown in Figures 4, 5, and 8, the portion of the shaping portion 16 corresponding to the upper surface of the reinforcing portion 15 has a structure in which the first fiber-reinforced resin sheets 13 of the exterior body 10 are stacked vertically from the exterior body 10 side to the center of the top surface, and a structure in which the first fiber-reinforced resin sheets 13 of the exterior body 10 are stacked at an angle tangent to the cylindrical outer periphery of the reinforcing portion 15 from the center of the top surface toward the exterior of the exterior body 10. As a result, the band attachment portion 2 is configured to be formed by the reinforcing portion 15 and the shaping portion 16.

In this case, the reinforcing portion 15 and shaping portion 16 of the band attachment portion 2 are fixed by welding to the 12 o'clock and 6 o'clock side surfaces of the exterior body 10, as shown in Figures 4, 5, and 8. That is, the first fiber-reinforced resin sheet 13 of the exterior body 10 and shaping portion 16 is a sheet made of synthetic resin with fibers arranged in an array, and the second fiber-reinforced resin sheet 14 of the reinforcing portion 15 is a sheet made of synthetic resin with carbon fibers arranged in an array.

For this reason, as shown in Figures 4, 5, and 8, the reinforcing portion 15 and shaping portion 16 of the band attachment portion 2 are firmly secured to each other by heating and melting the synthetic resins of the first fiber-reinforced resin sheet 13 and the second fiber-reinforced resin sheet 14, and then welding them together in this state by thermocompression bonding.

As shown in Figures 4, 6 to 8, a protective layer 17, which is a protective member, is provided on the outer surfaces of the protrusions 12 on the 3 o'clock and 9 o'clock sides that protrude from the outer periphery of the exterior member 6, and on the outer surfaces of the band attachment portions 2 on the 12 o'clock and 6 o'clock sides. This protective layer 17 is intended to protect the layered surface of the first fiber-reinforced resin sheet 13 of the exterior body 10, and is formed from a third fiber-reinforced resin sheet 18, which is a third fiber-reinforced resin sheet with fibers oriented in a direction intersecting the layering direction of the first fiber-reinforced resin sheet 13.

In this case, the third fiber-reinforced resin sheet 18 may be a glass fiber-reinforced resin sheet in which glass fibers are arranged and solidified with synthetic resin, as shown in FIG. 4, but is preferably a carbon fiber-reinforced resin sheet in which carbon fibers are arranged and solidified with synthetic resin. This third fiber-reinforced resin sheet 18 may be one in which the carbon fibers are arranged in one direction intersecting the stacking direction of the first fiber-reinforced resin sheet 13 of the exterior body 10, but is preferably a mesh-like sheet in which the carbon fibers are arranged crosswise in two directions intersecting the stacking direction of the first fiber-reinforced resin sheet 13 of the exterior body 10.

In other words, as shown in Figure 4, the mesh-like third fiber-reinforced resin sheet 18 has carbon fibers arranged crosswise in two directions that intersect the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10, resulting in higher rigidity and strength than a sheet in which the carbon fibers are arranged in only one direction that intersects the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10. As shown in Figures 6 to 8, this third fiber-reinforced resin sheet 18 is fixed by welding to the surface of the protrusion 12 and the surface of the band attachment portion 2.

In other words, as shown in Figures 6 to 8, the third fiber-reinforced resin sheet 18 is a sheet in which carbon fibers are arranged crosswise in two directions that intersect the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10 and solidified with synthetic resin. Therefore, the third fiber-reinforced resin sheet 18 is configured to be firmly fixed to the first fiber-reinforced resin sheet 13 of the exterior body 10 by heating and melting the synthetic resins of the first fiber-reinforced resin sheet 13 of the exterior body 10 and then welding them together in this state by thermocompression bonding.

In addition, as shown in Figures 6 to 8, the third fiber-reinforced resin sheet 18 of this protective layer 17 is formed on the surface of the first fiber-reinforced resin sheet 13 laminated to the exterior body 10, so that it prevents peeling or damage to the first fiber-reinforced resin sheet 13 when the laminated surface of the first fiber-reinforced resin sheet 13 on the exterior body 10 receives an impact.

Next, the assembly of such a wristwatch case 1 will be described.
In this case, the exterior member 6 is manufactured in advance. That is, first, the first fiber reinforced resin sheets 13 are stacked one on top of the other to form the substantially ring-shaped exterior main body 10. At this time, the first fiber reinforced resin sheets 13 are stacked so that their fiber directions are different and alternately cross each other, and the synthetic resins of these stacked first fiber reinforced resin sheets 13 are melted and fixed.

As a result, the first fiber-reinforced resin sheets 13 are stacked one on top of the other to form the roughly ring-shaped exterior body 10. In this case, protrusions 12 are formed on the 3 o'clock and 9 o'clock sides of the exterior body 10. That is, as shown in Figure 7, these protrusions 12 are formed by stacking the first fiber-reinforced resin sheets 13 one above the other, in the same way as the exterior body 10.

In this state, the band attachment sections 2 are provided on the 12 o'clock and 6 o'clock sides of the exterior body 10. At this time, the reinforcing section 15 of the band attachment section 2 is formed in advance. In this case, the second fiber-reinforced resin sheet 14, which is a carbon fiber-reinforced resin sheet, is wrapped concentrically around the band attachment hole 2a of the band attachment section 2 to form a cylindrical shape. This forms a cylindrical reinforcing section 15 with the band attachment hole 2a extending through it in the axial direction.

In this case, the carbon fiber direction of the second fiber-reinforced resin sheet 14 when wrapped around the tube is either perpendicular or transverse to the axial direction of the band attachment hole 2a. In other words, the second fiber-reinforced resin sheet 14 is formed so that the fibers are oriented in a direction that receives a tensile force when the watch band (not shown) attached to the band attachment portion 2 is pulled in its longitudinal direction. This allows the second fiber-reinforced resin sheet 14 to form a high-strength reinforcing portion 15.

In this case, the band attachment portion 2 is formed by a reinforcing portion 15 and a shaping portion 16. That is, the shaping portion 16 is formed by a portion where the first fiber-reinforced resin sheets 13 are stacked vertically and a portion where the first fiber-reinforced resin sheets 13 are stacked at an angle. Therefore, the band attachment portion 2, which includes the cylindrical reinforcing portion 15 and the shaping portion 16 concentrically formed by the second fiber-reinforced resin sheet 14, is fixed to each side of the exterior body 10 on the 12 o'clock and 6 o'clock sides.

In this case, the first fiber-reinforced resin sheet 13 of the exterior body 10 and the shaping portion 16, and the second fiber-reinforced resin sheet 14 of the reinforcing portion 15 are sheets in which fibers are solidified with synthetic resin. Therefore, with the reinforcing portion 15 and the shaping portion 16 of the band attachment portion 2 positioned on each side of the 12 o'clock and 6 o'clock sides of the exterior body 10, the synthetic resin of each stacked fiber-reinforced resin sheet is heated and melted, and in this state the sheets are welded and fixed to each other by thermocompression.

This firmly secures the reinforcing portion 15 and shaping portion 16 of the band attachment portion 2 to the side of the exterior body 10. In this case, the shaping portion 16 of the band attachment portion 2 may be formed in advance on the side of the exterior body 10, and the reinforcing portion 15 of the band attachment portion 2 may be welded and secured to this shaping portion 16 by thermocompression bonding.

In this state, a protective layer 17 is provided on each surface of the protrusions 12 and band attachment portion 2 that protrude from the outer peripheral surface of the exterior body 10. In this case, the protective layer 17 may be provided over the entire outer peripheral surface of the exterior body 10, but it is sufficient to provide it only on at least the surfaces of the protrusions 12 and band attachment portion 2 that protrude from the outer peripheral surface of the exterior body 10.

This protective layer 17 is formed by a third fiber-reinforced resin sheet 18 in which fibers are arranged in two directions intersecting the lamination direction of the first fiber-reinforced resin sheet 13 that forms the exterior body 10. In this case, the third fiber-reinforced resin sheet 18 is a carbon-fiber-reinforced resin sheet in which carbon fibers are solidified with synthetic resin, and is in the form of a mesh in which the carbon fibers are arranged crosswise in two directions intersecting the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10.

In other words, the mesh-like third fiber-reinforced resin sheet 18 has carbon fibers arranged crosswise in two directions intersecting the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10, resulting in higher rigidity and strength than a sheet in which the carbon fibers are arranged in only one direction intersecting the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10. The protective layer 17 of this third fiber-reinforced resin sheet 18 can then be fixed by welding to at least the surfaces of the protrusion 12 and the band attachment portion 2. In this case, the third fiber-reinforced resin sheet 18 may also be fixed by welding to the entire outer peripheral surface of the exterior body 10.

As a result, the third fiber-reinforced resin sheet 18 of the protective layer 17 is formed on the layered surface of the first fiber-reinforced resin sheet 13, which is the surface of the exterior body 10 on which the first fiber-reinforced resin sheet 13 is laminated. Therefore, when the layered surface of the exterior body 10 on which the first fiber-reinforced resin sheet 13 is laminated receives an impact, the third fiber-reinforced resin sheet 18 of the protective layer 17 prevents the first fiber-reinforced resin sheet 13 from peeling off or breaking, and protects the layered surface of the first fiber-reinforced resin sheet 13 of the exterior body 10.

The inner and outer surfaces of the exterior case body 10 formed in this manner are machined to shape the exterior case body 10. Specifically, the exterior case body 10 is machined except for the protrusions 12 and the band attachment portion 2, forming anti-slip recesses 10b on the 3 o'clock and 9 o'clock sides of the interior surface of the exterior case body 10, and attachment recesses 11 on the 1 o'clock, 5 o'clock, 7 o'clock, and 11 o'clock sides of the top surface of the exterior case body 10.

At this time, the outer peripheral surface of the exterior body 10 is machined, excluding the protrusions 12 and the band attachment portion 2, so that the layered surface of the first fiber-reinforced resin sheet 13 appears on the outer peripheral surface. As a result, the lamination lines of the first fiber-reinforced resin sheet 13 on the outer peripheral surface of this exterior member 6 are expressed as horizontal stripes, and the stripes caused by the lamination lines of the first fiber-reinforced resin sheet 13 enhance the design and increase the product value.

At this time, switch insertion holes 10a are formed at the 2 o'clock, 3 o'clock, 4 o'clock, 8 o'clock, and 10 o'clock sides of the exterior body 10 by drilling. Also, screw holes 11a are formed in the mounting recesses 11 at the 1 o'clock, 5 o'clock, 7 o'clock, and 11 o'clock sides on the top surface of the exterior body 10. This allows the exterior member 6 to be formed accurately and satisfactorily.

Next, assembling the wristwatch case 1 using such an exterior member 6 will be described.
In this case, first, the lower case 4 is inserted from above into the exterior member 6. At this time, the engagement protrusions 4b provided on the outer periphery on the 3 o'clock and 9 o'clock sides of the lower case 4 are inserted from above into the retaining recesses 10b provided on the inner periphery on the 3 o'clock and 9 o'clock sides of the exterior member 6, and the engagement protrusions 4b are locked in the retaining recesses 10b.

At this time, the multiple switch mounting holes 4a provided on the 2 o'clock, 3 o'clock, 4 o'clock, 8 o'clock, and 10 o'clock sides of the lower case 4 are aligned with the multiple switch insertion holes 10a provided on the 2 o'clock, 3 o'clock, 4 o'clock, 8 o'clock, and 10 o'clock sides of the exterior member 6. In this state, the multiple switches 3 are inserted from the outer periphery of the exterior member 6 through the switch insertion holes 10a in the exterior member 6 and into the switch mounting holes 4a in the lower case 4.

Then, a watch module (not shown) is placed inside the lower case 4. In this state, the upper case 5 is placed and attached above the lower case 4 and exterior member 6. At this time, the watch crystal 7 is first fitted into the upper case 5 together with the crystal gasket 7a. Then, a waterproof ring 5a is placed between the bottom surface of the upper case 5 and the top surface of the lower case 4, and in this state, the upper case 5 is placed above the lower case 4 and exterior member 6.

In this case, the multiple screw mounting portions 8 provided on each of the 1 o'clock, 5 o'clock, 7 o'clock, and 11 o'clock sides of the upper case 5 are aligned with the multiple mounting recesses 11 provided on each of the 1 o'clock, 5 o'clock, 7 o'clock, and 11 o'clock sides of the top surface of the exterior member 6. Then, the disk portions 8b of the multiple screw mounting portions 8 are positioned within the multiple mounting recesses 11, and the screw insertion holes 8c of each disk portion 8b are aligned with the screw holes 11a of each mounting recess 11.

In this state, the threaded portions 9a of the multiple screw members 9 are inserted into the screw insertion holes 8c of the disk portions 8b along the grooves 8a of the screw mounting portions 8 of the upper case 5, and the inserted screw portions 9a are threaded into the threaded holes 11a of the mounting recesses 11. The screw members 9 are then tightened to position the screw heads 9b on the disk portions 8b of the screw mounting portions 8. The screw heads 9b then press the upper case 5 against the exterior member 6. This pulls the exterior member 6 up toward the upper case 5.

At this time, the engagement projections 4b of the lower case 4 engage with the retaining recesses 10b of the exterior member 6, so when the exterior member 6 is pulled up toward the upper case 5, the lower case 4 is also pulled up at the same time. As a result, the upper end surface of the lower case 4 is pressed against the lower end surface of the upper case 5 via the waterproof ring 5a. In this way, the watch case 1 is assembled, and the watch is also assembled at the same time.

In this way, the exterior member 6 of this wristwatch case 1 comprises the exterior body 10 and the reinforcing portion 15, which is a tubular member made of fiber-reinforced resin and provided on the exterior body 10, thereby achieving weight reduction and increasing strength to improve impact resistance.

In addition, the exterior member 6 of this wristwatch case 1 has an exterior body 10 formed by laminating a first fiber-reinforced resin sheet 13, and a cylindrical reinforcing portion 15 formed by a cylindrical second fiber-reinforced resin sheet 14, which not only reduces weight but also increases strength and impact resistance.

The exterior member 6 of this watch case 1 also includes a band attachment section 2 to which a watch band (not shown) is attached, and a reinforcing section 15, which is a cylindrical member, is provided on the band attachment section 2, thereby increasing the strength of the band attachment section 2.

In this case, in the exterior member 6 of this watch case 1, the fibers of the second fiber-reinforced resin sheet 14 are arranged in a direction that intersects the cylindrical axis, thereby increasing the strength of the second fiber-reinforced resin sheet 14 in a direction perpendicular to the cylindrical axis. For example, if a cylindrically wound second fiber-reinforced resin sheet 14 is provided on the band attachment portion 2 that protrudes from the outer periphery of the exterior main body 10 of the exterior member 6, when a watch band (not shown) attached to the band attachment portion 2 is pulled in its longitudinal direction, the fibers of the second fiber-reinforced resin sheet 14 are arranged to receive a force in the tensile direction, thereby increasing the strength of the second fiber-reinforced resin sheet 14.

In addition, by concentrically winding the second fiber-reinforced resin sheet 14 around the exterior member 6 of this wristwatch case 1, the second fiber-reinforced resin sheet 14 can be wound concentrically in multiple layers, thereby reliably increasing the rigidity and strength of the cylindrically formed second fiber-reinforced resin sheet 14.

The exterior member 6 of this wristwatch case 1 also includes a band attachment section 2 to which a watch band (not shown) is attached. The second fiber-reinforced resin sheet 14 is wound and stacked concentrically around the band attachment hole 2a of the band attachment section 2, allowing the second fiber-reinforced resin sheet 14 to be wound concentrically in multiple layers. This allows the reinforcing section 15 of the second fiber-reinforced resin sheet 14 to be provided with band attachment holes 2a, which are through-holes in the axial direction of the tube. Even with the band attachment holes 2a provided in the second fiber-reinforced resin sheet 14, the rigidity and strength of the entire cylindrical second fiber-reinforced resin sheet 14 can be increased.

Furthermore, in the exterior member 6 of this wristwatch case 1, the second fiber-reinforced resin sheet 14 is welded to the first fiber-reinforced resin sheet 13 of the exterior body 10. Therefore, even if the second fiber-reinforced resin sheet 14 is formed into a cylindrical shape, this cylindrical second fiber-reinforced resin sheet 14 can be reliably and firmly fixed to the first fiber-reinforced resin sheet 13 of the exterior body 10 by welding.

In other words, in the exterior member 6 of this wristwatch case 1, the second fiber-reinforced resin sheet 14, like the first fiber-reinforced resin sheet 13 of the exterior body 10, is a sheet made of synthetic resin with carbon fibers or glass fibers arranged in an array. Therefore, by heating and melting these synthetic resins and then welding them together in this state using thermocompression bonding, the reinforcing portion 15 can be reliably and firmly fixed to the exterior body 10.

In addition, the exterior member 6 of this watch case 1 has a third fiber-reinforced resin sheet 18, whose fibers are arranged in a direction intersecting the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10, provided on the surface of the second fiber-reinforced resin sheet 14 that protrudes from the outer periphery of the exterior body 10.This means that even if the lamination surface of the first fiber-reinforced resin sheet 13 of the exterior body 10 receives an impact, the protective layer 17 of the third fiber-reinforced resin sheet 18 can prevent peeling or damage to the first fiber-reinforced resin sheet 13, thereby easily and effectively protecting the surface of the band attachment portion 2.

In this case, the exterior member 6 of this watch case 1 has a third fiber-reinforced resin sheet 18 on each surface of the protrusions 12 protruding from the outer periphery of the exterior body 10 and the band attachment portion 2. As a result, the lamination lines of the first fiber-reinforced resin sheet 13 appear as horizontal stripes on the outer surface of the exterior body 10 other than the protrusions 12 and the band attachment portion 2. This stripe pattern created by the lamination lines of the first fiber-reinforced resin sheet 13 enhances the design, resulting in a product with high commercial value.

In addition, in the exterior member 6 of this wristwatch case 1, the fibers of the third fiber reinforced resin sheet 18 are arranged crosswise in two directions, which makes the strength of the third fiber reinforced resin sheet 18 greater than that of a third fiber reinforced resin sheet 18 in which the fibers are arranged in one direction crossing the lamination direction of the first fiber reinforced resin sheet 13 of the exterior body 10.This makes it possible to more reliably prevent peeling or damage to the first fiber reinforced resin sheet 13 even if the lamination surface of the first fiber reinforced resin sheet 13 of the exterior body 10 is subjected to impact.

In other words, in the exterior member 6 of this wristwatch case 1, the fibers of the third fiber-reinforced resin sheet 18 are arranged crosswise in two directions, allowing the fibers to be arranged in a mesh-like pattern. The third fiber-reinforced resin sheet 18, with its fibers arranged in a mesh-like pattern, increases the rigidity and strength of the protective layer 17. Therefore, even if the laminated surface of the first fiber-reinforced resin sheet 13 of the exterior body 10 receives an impact, the protective layer 17 can more reliably prevent peeling or damage to the first fiber-reinforced resin sheet 13.

Furthermore, in the exterior member 6 of this wristwatch case 1, the third fiber-reinforced resin sheet 18 is a carbon fiber-reinforced resin sheet, which also increases the rigidity and strength of the protective layer 17 of the third fiber-reinforced resin sheet 18. Therefore, even if the laminated surface of the first fiber-reinforced resin sheet 13 of the exterior body 10 receives an impact, the protective layer 17 of the third fiber-reinforced resin sheet 18 can reliably and effectively prevent peeling or damage to the first fiber-reinforced resin sheet 13.

In the above-described embodiment, the third fiber-reinforced resin sheet 18 is provided on each surface of the protrusion 12 protruding from the outer peripheral surface of the exterior body 10 and the band attachment portion 2. However, the present invention is not limited to this, and the third fiber-reinforced resin sheet 18 may be provided over the entire outer peripheral surface of the exterior body 10.

In this case, because the third fiber-reinforced resin sheet 18 is provided over the entire outer peripheral surface of the exterior body 10, the third fiber-reinforced resin sheet 18, which serves as the protective layer 17, can prevent the first fiber-reinforced resin sheet 13 from peeling off or breaking even if the laminated surface of the first fiber-reinforced resin sheet 13 of the exterior body 10 receives an impact, thereby reliably and effectively protecting the outer peripheral surface of the exterior body 10.

In addition, in the above-described embodiment, the protective layer 17 has been described as having the fibers of the third fiber-reinforced resin sheet 18 arranged in a mesh pattern in two directions intersecting the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10. However, the present invention is not limited to this. For example, the present invention may have a structure in which the fibers of the third fiber-reinforced resin sheet 18 are arranged in one direction intersecting the lamination direction of the first fiber-reinforced resin sheet 13 of the exterior body 10. In this case, too, peeling or damage to the first fiber-reinforced resin sheet 13 can be prevented even if the lamination surface of the first fiber-reinforced resin sheet 13 of the exterior body 10 is subjected to an impact.

In addition, in the above-described embodiment, the reinforcing portion 15 is formed into a cylindrical shape by concentrically wrapping the second fiber-reinforced resin sheet 14 around it. However, the present invention is not limited to this. For example, the second fiber-reinforced resin sheet 14 may be wrapped around an elliptical shape to form an elliptical cylindrical shape, or the second fiber-reinforced resin sheet 14 may be wrapped around a polygonal shape such as a triangle, square, or pentagon to form a polygonal cylindrical shape.

In this way, the second fiber-reinforced resin sheet 14 can be wrapped concentrically in multiple layers to form the reinforcing portion 15 into an elliptical or polygonal cylindrical shape. This allows the reinforcing portion 15 to be formed into any shape depending on its intended use. Furthermore, even if the reinforcing portion 15 of the second fiber-reinforced resin sheet 14 is formed into any shape, the rigidity and strength of the reinforcing portion 15 of the second fiber-reinforced resin sheet 14 can be ensured.

In addition, in the above-described embodiment, the upper case 5 is formed from a metal such as stainless steel or a hard synthetic resin, but the present invention is not limited to this. For example, the upper case 5 may have a structure formed by laminating a first fiber-reinforced resin sheet 13, similar to the exterior member 6.

Furthermore, while the above-described embodiment has been described as being applied to a wristwatch, this invention does not necessarily have to be a wristwatch, and can be applied to various types of clocks, such as travel watches, alarm clocks, table clocks, and wall clocks. Furthermore, this invention does not necessarily have to be a clock, and can also be applied to electronic devices such as mobile phones and personal digital assistants.

Although one embodiment of the present invention has been described above, the present invention is not limited to this and includes the inventions set forth in the claims and their equivalents.
The inventions described in the claims of this application are as follows:

(Additional Note)
The invention described in claim 1 is an exterior member comprising: an exterior body; and a tubular member made of fiber reinforced resin and provided on the exterior body.

The invention described in claim 2 is the exterior member described in claim 1, characterized in that the exterior main body is formed by laminating first fiber-reinforced resin sheets, and the tubular member is a second fiber-reinforced resin sheet arranged in a tubular shape.

The invention described in claim 3 is the exterior member described in claim 1 or claim 2, characterized in that it includes a band attachment portion to which a band is attached, and the tubular member is provided on the band attachment portion.

The invention described in claim 4 is the exterior member described in claim 2, characterized in that the fibers of the second fiber-reinforced resin sheet are arranged in a direction that intersects with the cylindrical axis.

The invention described in claim 5 is an exterior member according to claim 2 or claim 4, characterized in that the second fiber-reinforced resin sheet is concentrically wrapped.

The invention described in claim 6 is an exterior member according to any one of claims 2, 4, and 5, further comprising a band mounting portion to which a band is attached, and the second fiber-reinforced resin sheet is laminated and wrapped concentrically around the band mounting hole of the band mounting portion.

The invention described in claim 7 is an exterior member according to any one of claims 2, 4, 5, and 6, characterized in that the second fiber-reinforced resin sheet is welded to the first fiber-reinforced resin sheet of the exterior body.

The invention described in claim 8 is an exterior member according to claim 3 or claim 6, characterized in that a third fiber-reinforced resin sheet, whose fibers are oriented in a direction intersecting the lamination direction of the first fiber-reinforced resin sheet of the exterior main body, is provided on the surface of the band attachment portion.

The invention described in claim 9 is a watch characterized by having an exterior member described in any one of claims 1 to 8.

DESCRIPTION OF SYMBOLS 1 Wristwatch case 2 Band attachment portion 2a Band attachment hole 3 Switch portion 4 Lower case 4a Switch attachment hole 4b Engagement protrusion 5 Upper case 5a Waterproof ring 6 Exterior member 7 Watch crystal 8 Screw attachment portion 8a Groove portion 8b Disc portion 8c Screw insertion hole 9 Screw member 9a Threaded portion 9b Screw head 10 Exterior body 10a Switch insertion hole 10b Anti-pullout recess 11 Mounting recess 11a Screw hole 12 Protrusion 13 First fiber reinforced resin sheet 14 Second fiber reinforced resin sheet 15 Reinforcement portion 16 Shaped portion 17 Protective layer 18 Third fiber reinforced resin sheet

Claims (9)

The exterior body and
A cylindrical member that is a second fiber reinforced resin sheet provided on the exterior main body and provided in a cylindrical shape ;
An exterior member comprising: The exterior member according to claim 1,
The exterior body is formed by laminating a first fiber reinforced resin sheet,
An exterior member characterized by: The exterior member according to claim 1 or 2,
A band attachment portion is provided to which a band can be attached,
The exterior member, wherein the cylindrical member is provided at the band attachment portion. The exterior member according to claim 2,
The exterior member, wherein the second fiber reinforced resin sheet has fibers arranged in a direction intersecting a cylindrical axis of the cylindrical member. The exterior member according to claim 2 or 4,
The exterior member, wherein the second fiber reinforced resin sheet is concentrically wound. The exterior member according to any one of claims 2, 4, and 5,
A band attachment portion is provided to which a band can be attached,
The exterior member, wherein the second fiber reinforced resin sheet is laminated by being wound concentrically around the band mounting hole of the band mounting portion. In the exterior member according to any one of claims 2, 4, 5, and 6,
The exterior member, wherein the second fiber reinforced resin sheet is welded to the first fiber reinforced resin sheet of the exterior body. The exterior member according to claim 3 or claim 6,
a third fiber-reinforced resin sheet having fibers arranged in a direction intersecting a lamination direction of the first fiber-reinforced resin sheet of the exterior body is provided on a surface of the band attachment portion. A watch comprising an exterior member according to any one of claims 1 to 8.