Band manufacturing method and band

Abstract

Provided is a band manufacturing method that enables the appropriate closing of a pin hole.　This band manufacturing method is for manufacturing a band formed by connecting a plurality of pieces to each other, said method including: a preparation step for preparing a band in which a pin hole is formed that stretches in a width direction of the band, the pin hole including a small diameter part, and a large diameter part connected to the outside in the width direction of the small diameter part and having the inner diameter larger than that of the small diameter part; an arrangement step for arranging, outside in the width direction of the pin hole, a lid member including a fixing part and a closing part connected to the fixing part and formed such that the outer diameter decreases toward the fixing part; and a closing step for displacing the lid member inward in the width direction to close the pin hole. In the closing step, the fixing part contacts an inner wall of the small diameter part to fix the lid member to the pin hole, and the closing part closes the outer end of the large diameter part.

Description

Band manufacturing method and band

[0001] The present invention relates to a method for manufacturing a band and to a band.

[0002] Bands formed by connecting multiple links are used in wristwatches and the like. A known method for decorating such bands is to use pin-shaped cover members to close the pin holes used to connect the multiple links. For example, Patent Document 1 describes a method in which a pin-shaped member having a first press-fit portion, a second press-fit portion, and a neck portion that connects the first press-fit portion and the second press-fit portion is press-fitted into the pin holes to close them. The pin-shaped member has a neck portion with a diameter smaller than that of the first press-fit portion and the second press-fit portion.

[0003] Japanese Patent Application Publication No. 11-262403

[0004] If the hardness of the pin-shaped member is lower than that of the link in which the pin hole is formed, the pin will deform, making press-fitting difficult. Therefore, pin-shaped members are generally formed to have a higher hardness than the link. On the other hand, when a pin-shaped member with high hardness is used, the pin hole may widen more than necessary due to an error in the press-fitting direction, resulting in a void between the pressed-fit pin-shaped member and its surroundings. The void may cause liquids, such as cleaning fluids, used in the band manufacturing process to seep in and leak out, and may accentuate the boundary between the cover member and the link, detracting from the aesthetic appearance of the band. Therefore, a method for properly closing the pin hole while suppressing the formation of voids is needed.

[0005] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a band and a method for manufacturing the band that allows pin holes to be properly closed.

[0006] A band according to an embodiment of the present invention comprises a plurality of links extending in the width direction so as to penetrate two adjacent links, and each link having a pin hole formed therein, the pin hole including a small diameter portion and a large diameter portion connected to the outside of the small diameter portion in the width direction and having an inner diameter larger than that of the small diameter portion; and a cover member having a fixing portion and a blocking portion connected to the fixing portion and formed so that its outer diameter decreases toward the fixing portion, the fixing portion abutting against the inner wall of the small diameter portion to fix the cover member to the pin hole, and the blocking portion blocking the outer end of the large diameter portion.

[0007] Moreover, it is preferable that the fixing portion is formed in a columnar shape having a uniform outer diameter.

[0008] Moreover, it is preferable that the fixing portion is formed in a tapered shape having a smaller taper angle than the closing portion.

[0009] It is also preferable that the band further has a frictional bonding region formed in the bonding region between the fixed portion and the small diameter portion, where the piece and the cover member are frictionally bonded, and a plastic deformation region formed in the bonding region between the blocking portion and the large diameter portion, where the piece and the cover member are plastically deformed.

[0010] It is also preferable that the plastic deformation region further has a protrusion that is connected to the frictional bonding region and protrudes outward from the frictional bonding region in the radial direction of the cover member.

[0011] The cover member is preferably made of the same material as the bridge.

[0012] Preferably, the material is titanium.

[0013] A method for manufacturing a band according to an embodiment of the present invention is a method for manufacturing a band formed by connecting a plurality of links to each other, and includes the following steps: a preparation step of preparing a band having a pin hole extending in the width direction of the band and having a small diameter portion and a large diameter portion connected to the outside of the small diameter portion in the width direction and having an inner diameter larger than that of the small diameter portion; an arrangement step of arranging a cover member outward in the width direction of the pin hole, the cover member having a fixing portion and a blocking portion connected to the fixing portion and formed so that its outer diameter decreases toward the fixing portion; and a blocking step of displacing the cover member inward in the width direction to block the pin hole, wherein in the blocking step, the fixing portion abuts against the inner wall of the small diameter portion to fix the cover member to the pin hole, and the blocking portion blocks the outer end of the large diameter portion.

[0014] In the closing step, it is preferable that the cover member be press-fitted into the pin hole to press-fit and fix the fixing portion to the inner wall of the first region.

[0015] Preferably, the method further includes, after the closing step, a removing step of removing a portion of the lid member that protrudes outward in the width direction from the band.

[0016] The band manufacturing method and the band according to the present invention make it possible to properly close the pin holes.

[0017] 1 is a plan view of a band according to a first embodiment; FIG. 2 is a flow diagram showing an example of the flow of a manufacturing method for a band according to the first embodiment; FIG. 3 is a partial perspective view of a pin hole and a lid member in a positioning step of the band according to the first embodiment; FIG. 4 is a partial cross-sectional view of a pin hole and a lid member in a closing step of the band according to the first embodiment; FIG. 5 is a partial cross-sectional view of a link and a lid member of the band according to the first embodiment; (A) is a photograph showing the vicinity of the lid member of the band according to the first embodiment, and (B) is a photograph showing the vicinity of the lid member of a band manufactured by a manufacturing method according to conventional technology; FIG. 6 is a partial cross-sectional view of a pin hole and a lid member in a closing step of the band according to the second embodiment; FIG. 7 is a partial cross-sectional view of a pin hole and a lid member in a closing step of the band according to the third embodiment; FIG. 8 is a partial cross-sectional view of a pin hole and a lid member in a closing step of the band according to the fourth embodiment; FIG. 9 is a partial cross-sectional view of a pin hole and a lid member after the closing step and before the removal step of the band according to the fourth embodiment; FIG. 10 is a partial cross-sectional view of a link and a lid member of the band according to the fourth embodiment; FIG. 11 is a photograph showing a cross-section of a link and a lid member of the band according to the fourth embodiment.

[0018] Various embodiments of the present invention will be described below with reference to the drawings. Please note that the technical scope of the present invention is not limited to these embodiments, but extends to the inventions described in the claims and their equivalents.

[0019] FIG. 1 is a plan view of a band 1 according to a first embodiment of the present invention. The band 1 has a flat plate shape extending in a predetermined extension direction D1 and is used in wristwatches and the like. The band 1 has a plurality of links 2, pins 3, and a cover member 4. Hereinafter, the direction along the band 1 that is perpendicular to the extension direction D1 may be referred to as the width direction D2. In particular, the direction toward the center of the band 1 in the width direction D2 may be referred to as the inward direction D3 in the width direction D2, and the direction away from the center of the band 1 in the width direction D2 may be referred to as the outward direction D4 in the width direction D2.

[0020] A plurality of links 2 are interconnected to form the band 1. In the example shown in FIG. 1 , each link 2 is integrally formed and has a generally Y-shaped planar shape in which a central portion 21 and an end portion 22 in the width direction D2 protrude in different directions along the extension direction of the band 1. The links 2 are formed of a metal material. Preferably, the links 2 are formed of pure titanium. Each link 2 has a through-hole 23 penetrating the central portion 21 in the width direction D2 and a through-hole 24 penetrating the end portion 22 in the width direction D2. When the links 2 are connected, the through-hole 23 in the central portion 21 of one of two adjacent links communicates with the through-hole 24 in the end portion 22 of the other link, forming a pin hole 25 penetrating the band 1 in the width direction D2. In FIG. 1 , the pin hole 25 and the components arranged therein are indicated by dashed lines.

[0021] The pin 3 is a shaft-shaped member that is inserted into the pin hole 25 to connect the bridge 2. With the pin 3 inserted, the bridge 2 can rotate around the pin 3.

[0022] The cover members 4 are disposed on both ends of the pin holes 25 to close the pin holes 25. Preferably, the cover members 4 are made of a metal material having the same hardness as the bridge 2. More preferably, the cover members 4 are made of pure titanium, which is the same material as the bridge 2.

[0023] FIG. 2 is a flow chart showing an example of the flow of a method for manufacturing the band 1.

[0024] First, a preparation step is carried out (step S1) to prepare a band 1 having pin holes 25. Pins 3 are inserted into the pin holes 25 of the prepared band 1, and a plurality of links 2 are connected by the pins 3.

[0025] Next, a placement step is performed in which the cover member 4 is placed outside the pin hole 25 in the width direction (step S2).

[0026] FIG. 3 is a partial perspective view of the pin hole 25 and the cover member 4 in the placement process.

[0027] 3, the pin hole 25 is composed of a small diameter portion 251 and a large diameter portion 252. The small diameter portion 251 and the large diameter portion 252 are each formed in a circular shape, and the large diameter portion 252 has a larger inner diameter than the small diameter portion 251. For example, the inner diameter of the small diameter portion 251 is 0.98 mm, and the inner diameter of the large diameter portion 252 is 1.1 mm. The large diameter portion 252 is connected to the outside D4 of the small diameter portion 251 in the width direction D2 so as to be coaxial with the small diameter portion 251.

[0028] The lid member 4 has a fixed portion 41 and a closing portion 42. The fixed portion 41 is formed in a generally cylindrical shape with a uniform outer diameter. The outer diameter of the fixed portion 41 is slightly larger than the inner diameter of the small diameter portion 251 and smaller than the inner diameter of the large diameter portion 252. For example, the outer diameter of the fixed portion 41 is 1.0 mm. The outer edge of one bottom surface of the fixed portion 41 is chamfered to form a tapered inclined portion 411 so that the lid member 4 can easily enter the small diameter portion 251. The closing portion 42 is formed in a shape in which a truncated cone and a cylinder are joined together so that they are coaxial, and is connected to the fixed portion 41 at the upper bottom surface of the truncated cone portion. In other words, the closing portion 42 is formed in a tapered shape so that the outer diameter decreases toward the fixed portion 41. The outer diameter of the cylindrical portion of the closing portion 42 is larger than the inner diameter of the large diameter portion 252. For example, the outer diameter of the cylindrical portion of the closing portion 42 is 1.3 mm. The cover member 4 is arranged so that the fixing portion 41 is located inward D3 in the width direction D2 and the closing portion 42 is located outward D4 in the width direction D2.

[0029] For the sake of convenience in explaining the shape of the cover member 4, the closing portion 42 is connected to the fixing portion 41 at the upper bottom surface of the truncated cone portion, but the fixing portion 41 and the closing portion 42 may be formed integrally. That is, in reality, the closing portion 42 does not need to have an upper bottom surface.

[0030] 2, next, a closing step is performed (step S3) in which the cover member 4 is displaced inward in the width direction to close the pin holes 25. The cover member 4 is press-fitted into the pin holes 25 to close the pin holes 25.

[0031] 4 and 5 are partial cross-sectional views of the pin hole 25 and the cover member 4 during the closing step. In Fig. 5, the shape of the pin hole 25 before the closing step is shown by a dashed line. When the cover member 4 is press-fitted into the pin hole 25, the side surface of the fixing portion 41 first comes into contact with the inner wall 253 of the small diameter portion 251, as shown in Fig. 4. At this time, because the outer diameter of the fixing portion 41 is slightly larger than the inner diameter of the small diameter portion 251, a large radial force is applied between the fixing portion 41 and the inner wall of the small diameter portion 251.

[0032] When the cover member 4 is further press-fitted from the state shown in Fig. 4 , the closing portion 42 comes into contact with the inner wall 254 of the large-diameter portion 252, deforming the large-diameter portion 252, as shown in Fig. 5 . At this time, because the closing portion 42 is tapered, the force applied from the closing portion 42 to the inner wall of the large-diameter portion 252 includes a component F1 in a direction expanding the diameter of the large-diameter portion 252 and a component F2 in a direction along the press-fitting direction D3. Therefore, the force expanding the diameter of the large-diameter portion 252 is weaker than when the closing portion 42 is columnar. Furthermore, because the closing portion 42 is tapered, even if the diameter of the large-diameter portion 252 expands, the cover member 4 is displaced inward D3 in the width direction D2, thereby filling the gap between the cover member 4 and the link 2.

[0033] When the cover member 4 is press-fitted, the contact area between the fixing portion 41 and the inner wall of the small diameter portion 251 increases, and the pressure generated between the fixing portion 41 and the inner wall of the small diameter portion 251 increases, the cover member 4 stops and the fixing portion 41 is press-fitted and fixed in place against the inner wall of the small diameter portion 251. When the fixing portion 41 is press-fitted and fixed, the rear end 43 of the blocking portion 42 protrudes outward D4 in the width direction D2 from the side surface of the band 1, as shown in FIG.

[0034] As described above, in the closing process, the cover member 4 comes into contact with the inner wall of the pin hole 25 at two locations, the fixed portion 41 and the blocking portion 42. The contact surface between the fixed portion 41 and the small diameter portion 251 is parallel to the width direction D2, which is the press-fitting direction. Therefore, when the fixed portion 41 is press-fitted, a large radial force is applied between the fixed portion 41 and the small diameter portion 251, and the fixed portion 41 is firmly press-fitted and fixed to the inner wall 253 of the small diameter portion 251. Meanwhile, because the blocking portion 42 is tapered, the contact surface between the blocking portion 42 and the large diameter portion 252 is inclined with respect to the press-fitting direction. Therefore, the diameter of the large diameter portion 252 is prevented from expanding more than necessary, and even if the diameter of the large diameter portion 252 does expand, the tapered blocking portion 42 fills the gap, thereby properly closing the pin hole 25. That is, in the cover member 4, the side surface of the fixing portion 41 is parallel to the press-fit direction, so that the cover member 4 is firmly pressed in and fixed, and the blocking portion 42 is formed in a tapered shape, so that the gap is filled and the pin hole 25 is properly blocked.

[0035] 2, a removal step is carried out to remove the rear end portion 43 of the cover member 4 that protrudes outward in the width direction from the side surface of the band 1 (step S4). The rear end portion 43 is removed by cutting or polishing. In this manner, the band 1 is manufactured.

[0036] 6 is a partial cross-sectional view of the link 2 and the cover member 4 of the band 1, showing the state after the removal process has been performed. After the removal process has been performed, the end faces of the link 2 and the cover member 4 of the band 1 are integrated.

[0037] Figure 7(A) is an enlarged view of the vicinity of the cover member 4 of the band 1 manufactured by the method according to the embodiment described above. In Figure 7(A), because the gap between the cover member 4 and the link 2 is small, the boundary between the cover member 4 and the link 2 is not visible, as shown by the dashed rectangle. Furthermore, because the cover member 4 and the link 2 are made of the same metal material, pure titanium, the appearances of the end faces of the cover member 4 and the link 2 are generally consistent, and the end faces of the link 2 are integrated to create a highly aesthetic appearance.

[0038] Figure 7(B) is an enlarged view of the vicinity of the cap of a watch band manufactured by a method according to the prior art. In Figure 7(B), because the gap between the cap and the link is large, the boundary line between the cap and the link is visible as shown by the dashed rectangle. Furthermore, because the link is made of pure titanium while the cap is made of a titanium alloy, the appearance of the end surface of the cap and the end surface of the link are different.

[0039] As described above, the manufacturing method of the band 1 includes an arrangement step of arranging the cover member 4 on the outer side D4 of the pin hole 25 in the width direction D2, and a closing step of press-fitting the cover member 4 into the pin hole 25 to close the pin hole 25. The pin hole 25 also includes a small diameter portion 251 and a large diameter portion 252 that is connected to the outer side D4 of the small diameter portion 251 in the width direction D2 and has an inner diameter larger than that of the small diameter portion 251. The cover member 4 has a fixing portion 41 that abuts against the inner wall of the small diameter portion 251 to press-fit and fix the cover member 4 in the closing step, and a closing portion 42 that is tapered so that its outer diameter decreases inward D3 and that closes the outer end of the large diameter portion 252 in the closing step. This enables the band 1 to properly close the pin hole 25.

[0040] The fixing portion 41 is formed in a cylindrical shape with a uniform outer diameter, which allows the fixing portion 41 to be firmly press-fitted into the small diameter portion 251. This allows the band 1 to more appropriately close the pin hole 25.

[0041] The cover member 4 is made of the same material as the bridge 2. This unifies the appearance of the cover member 4 and the bridge 2, thereby improving the aesthetic appearance of the band 1.

[0042] The band 1 and its manufacturing method may be modified as follows.

[0043] In the above-described embodiment, the cover member 4 is made of the same material as the link 2. However, the present invention is not limited to this example, and the cover member 4 may be made of a different material from the link 2. In this case, no gap is created between the cover member 4 and the link 2, allowing the band 1 to properly close the pinhole. Furthermore, in the above-described embodiment, the cover member 4 does not need to have a higher hardness than the link 2, which increases the freedom of material selection.

[0044] In the above-described embodiment, in step S3 of the manufacturing method of the band 1, the cover member 4 is press-fitted into the pin hole 25 to be fixed to the pin hole 25. However, this is not a limitation, and the cover member 4 may be fixed to the pin hole 25 by other methods. For example, threads may be formed on the fixing portion 41 and the small diameter portion 251, and the fixing portion 41 may be fixed to the small diameter portion 251 by screwing. In this case, as the cover member 4 is displaced inward in the width direction due to the screwing, the blocking portion 42 comes into contact with the inner wall of the large diameter portion 252 and closes the pin hole 25. This also allows the pin hole 25 to be properly closed. In this case, in the removal process of step S4, it is preferable that the rear end portion 43 of the blocking portion 42 be removed together with the threaded hole formed in the end face of the blocking portion 42.

[0045] In the above-described embodiment, the removal step is performed in step S4 of the method for manufacturing the band 1. However, this is not limiting, and the removal step may be omitted. In this case, the length of the cover member 4 in the width direction D2 may be adjusted in advance so that the outer end surface D4 of the cover member 4 in the width direction D2 coincides with the side surface of the band 1 when the cover member 4 is press-fitted.

[0046] In the above-described embodiment, a tapered inclined portion 411 is formed on the outer edge of one bottom surface of the fixing portion 41. However, this is not a limitation, and the fixing portion 41 does not have to have the inclined portion 411. This makes it easier to manufacture the cover member 4. Generally, if no inclined portion is formed, errors in the press-fitting direction are likely to occur. However, by forming the closing portion 42 of the cover member 4 in a tapered shape, even if there is a slight error in the press-fitting direction, a gap is unlikely to occur between the cover member 4 and the bridge 2. Therefore, the cover member 4 can prevent the adverse effects caused by omitting the inclined portion 411.

[0047] In the above-described embodiment, the blocking portion 42 has a shape in which a truncated cone and a cylinder are joined together. However, the present invention is not limited to this example, and the blocking portion 42 may have a truncated cone shape. Furthermore, while the cover member 4 has a circular cross-sectional shape, the present invention is not limited to this example, and the blocking portion 42 may have a polygonal cross-sectional shape. In this case, the pin hole 25 may be formed with a polygonal cross-sectional shape so as to engage with the cover member 4.

[0048] 8 is a partial cross-sectional view of the pin hole and the lid member during the closing process of the band according to the second embodiment. The band according to the second embodiment differs from the band 1 according to the first embodiment in that it has a lid member 5 instead of the lid member 4. Other configurations of the band according to the second embodiment are the same as the corresponding configurations of the band 1, and therefore the same reference numerals are used and the description thereof will be omitted.

[0049] The cover member 5 differs from the cover member 4 in that it has a fixing portion 51 instead of the fixing portion 41. The fixing portion 51 is formed in a truncated cone shape whose outer diameter decreases inward D3 in the width direction D2 when the cover member 5 is press-fitted into the pin hole 25. The taper angle of the fixing portion 51 is formed to be smaller than the taper angle of the truncated cone portion of the closing portion 42.

[0050] Because the taper angle of the fixing portion 51 is smaller than the taper angle of the closing portion 42, the radial force generated between the fixing portion 51 and the inner wall of the small diameter portion 251 is greater than the radial force generated between the closing portion 42 and the inner wall of the large diameter portion 252. Therefore, because the fixing portion 51 has a small taper angle, the cover member 4 can be firmly press-fitted into the pin hole 25.

[0051] The band according to the second embodiment is manufactured by carrying out a removal process from the state shown in FIG. 8, and the end surfaces of the link 2 and the cover member 5 are integrated.

[0052] 9 is a partial cross-sectional view of the lid member and the vicinity of the pin hole in the closing process of the band according to the third embodiment. The band according to the third embodiment differs from the band 1 according to the first embodiment in that it has a link 6 instead of the link 2. Other components of the band according to the third embodiment are the same as the corresponding components of the band 1, so the same reference numerals are used and the description thereof will be omitted.

[0053] Bridge 6 differs from bridge 2 in that it has a pin hole 65 instead of pin hole 25. Pin hole 65 differs from pin hole 25 in that, instead of having a small diameter portion 251 and a large diameter portion 252, it has an inclined portion 655 whose inner diameter continuously increases outward D4 in the width direction D2. Note that in Figure 9, the shape of pin hole 65 before cover member 4 is press-fitted is shown by a dashed line. As shown in Figure 9, the inner wall of inclined portion 655 has a smaller taper angle than closing portion 42.

[0054] When the cover member 4 is press-fitted into the pin hole 65, the side surface of the fixing portion 41 first contacts a first portion 656 of the inner wall of the inclined portion 655, and a large radial force is applied between the fixing portion 41 and the first portion 656. When the cover member 4 is further press-fitted, the blocking portion 42 contacts a second portion 657 of the inner wall of the inclined portion 655, deforming the second portion 657 and blocking the pin hole 65. The second portion 657 is located outward D4 in the width direction D2 from the first portion 656, and the inner diameter of the second portion 657 of the pin hole 65 is larger than the inner diameter of the first portion 656. The first portion 656 and the second portion 657 are examples of a small diameter portion and a large diameter portion.

[0055] In this way, the cover member 4 comes into contact with the inner wall of the inclined portion 655 of the pin hole 65 at two locations: the fixed portion 41 and the blocking portion 42. As in the case of the pin hole 25, the side surface of the fixed portion 41 is parallel to the width direction D2, which is the press-fitting direction, so that the cover member 4 is firmly press-fitted and fixed, and the tapered shape of the blocking portion 42 fills the gap, so that the pin hole 65 is properly blocked.

[0056] The band according to the third embodiment is manufactured by carrying out a removal process from the state shown in FIG. 9, and the end surfaces of the link 6 and the cover member 4 are integrated.

[0057] Fig. 10 is a partial cross-sectional view of the pin holes 25 and the cover member 4 of the band 10 according to the fourth embodiment during the closing process, Fig. 11 is a partial cross-sectional view of the pin holes 25 and the cover member 4 of the band 10 according to the same embodiment after the closing process and before the removal process, and Fig. 12 is a partial cross-sectional view of the links 2 and the cover member 4 of the band 10 according to the same embodiment. The band 10 according to the fourth embodiment differs from the band 1 according to the first embodiment in that the force used to press the cover member 4 into the pin holes 25 during the closing process is greater than the force used during the closing process of the first embodiment. Other configurations of the band 10 according to the fourth embodiment are the same as the corresponding configurations of the band 1, so the same reference numerals are used and descriptions thereof will be omitted.

[0058] 10 shows the state of the pin hole 25 and the cover member 4 during the process of press-fitting the cover member 4. In this embodiment, the bridge 2 and the cover member 4 are made of pure titanium, an example of titanium. In the closing step, the cover member 4 is press-fitted into the pin hole 25 to close the pin hole 25. Because pure titanium is prone to plastic deformation, the cover member 4 is press-fitted into the pin hole 25 in a single press-fit. Furthermore, the force PF used to press the cover member 4 into the pin hole 25 is greater than the force used in the closing step in the first embodiment.

[0059] In the closing process, because the outer diameter of the fixing portion 41 is slightly larger than the inner diameter of the small diameter portion 251, as described above, a large radial force is applied between the fixing portion 41 and the inner wall 253 of the small diameter portion 251. When a press-fit force PF larger than that of the first embodiment is applied, the bridge 2 and the cover member 4 are friction-bonded using the frictional heat generated by the relative movement of the pure titanium members while they are in contact and pressurized.

[0060] Furthermore, when a press-fitting force PF greater than that of the first embodiment is applied during press-fitting, the relationship between the outer diameter of the fixed portion 41 and the inner diameter of the small diameter portion 251, and the formation of a frictional weld region 110 frictionally welds the bridge 2 and the cover member 4, suppressing inward movement D3 of the fixed portion 41. Therefore, the portion of the blocking portion 42 connected to the fixed portion 41 is sandwiched between the fixed portion 41 and the force PF, generating a radially outward force F3 of the cover member 4, causing plastic deformation. Furthermore, due to the cover member 4 plastically deformed by the force F3 and the component F2 in the press-fitting direction D3, a radially inward force F4 of the cover member 4 is generated on the inner wall 254 of the large diameter portion 252, causing plastic deformation.

[0061] 11 shows the state of the pinhole 25 and the cover member 4 after the cover member 4 has been press-fitted. After the cover member 4 has been press-fitted, a joint area 100 is formed where the link 2 and the cover member 4 are joined. Since the joint area 100 is the area where the link 2 and the cover member 4 are joined, it can be said that the link 2 and the cover member 4 each have a joint area 100.

[0062] The joining region 100 has a friction joining region 110 formed in the joining region 100 between the fixed portion 41 and the small diameter portion 251, where the piece 2 and the cover member 4 are frictionally joined, and a plastic deformation region 120 formed in the joining region 100 between the blocking portion 42 and the large diameter portion 252, where the piece 2 and the cover member 4 are plastically deformed.

[0063] The friction-bonded region 110 is a region where the pure titanium of the bridge 2 and the cover member 4 has melted and bonded together due to the frictional heat generated during the closing process. The friction-bonded region 110 has a portion where the pure titanium has melted due to the frictional heat, and its cross section has a whitish color. The friction-bonded region 110 is a portion where the bridge 2 and the cover member 4 are in close contact, and has rubbing marks. The rubbing marks are not smooth, and the friction-bonded region 110 can also be said to be a region where the pure titanium has burned together.

[0064] The plastic deformation region 120 is a region formed because pure titanium is a material that is susceptible to plastic deformation, in other words, has a low Young's modulus, and is the joining region 100 other than the friction-bonded region 110 that is fused and bonded by frictional heat. The plastic deformation region 120 is connected to the friction-bonded region 110 and has a protrusion 121 that protrudes outward from the friction-bonded region 110 in the radial direction of the lid member 4. The protrusion 121 is formed by the forces F3 and F4 (see FIG. 10 ) described above.

[0065] 12 shows the state of the link 2 and the cover member 4 after the removal process has been performed. After the removal process has been performed, the band 10 has a joining region 100, and the end surface of the link 2 and the end surface of the cover member 4 are integrated.

[0066] 13 is a photograph showing a cross section of the link 2 and the cover member 4 of the band 10 according to this embodiment. The frictional bonding region 110 of the bonding region 100 is formed in a generally cylindrical shape and has a whitish color as described above. The plastic deformation region 120 has a protrusion 121 at the connection portion with the frictional bonding region 110, and the diameter of the region outward in the width direction of the band from the protrusion 121 increases as it moves outward.

[0067] The band 10 according to this embodiment has a friction-bonded region 110 formed in the bonding region 100 between the fixed portion 41 and the small diameter portion 251, where the link 2 and the cover member 4 are friction-bonded, and a plastic deformation region 120 formed in the bonding region 100 between the closing portion 42 and the large diameter portion 252, where the link 2 and the cover member 4 are plastically deformed. This enables the band 10 to properly close the pin holes 25 without using adhesive or applying heat. Furthermore, by having the friction-bonded region 110, the band 10 can prevent the cover member 4 from coming off the link 2.

[0068] Furthermore, in the band 10 according to this embodiment, the plastic deformation region 120 is connected to the frictional bonding region 110 and has a protrusion 121 that protrudes outward from the frictional bonding region 110 in the radial direction of the cover member 4. This allows the link 2 and the cover member 4 to engage with each other, further preventing the cover member 4 from coming off the link 2.

[0069] Furthermore, in the band 10 according to this embodiment, the cover member 4 is formed from the same material as the links 2, which is pure titanium. This makes it easier for the links 2 and the cover member 4 to bond together during the closing process, compared to bands made of other metals, and allows the pin holes 25 to be properly closed. Furthermore, because titanium has biocompatibility, the band 10 can be designed with the user in mind.

[0070] In the fourth embodiment described above, the bridge 2 and the cover member 4 are made of the same material. However, the bridge 2 and the cover member 4 may be made of different materials, as in the first embodiment.

[0071] In the fourth embodiment described above, the bridge 2 and the cover member 4 are made of pure titanium. However, the bridge 2 and the cover member 4 may be made of a titanium alloy or other metal material. For example, the bridge 2 and the cover member 4 may be made of brass or gold.

[0072] In the above-described fourth embodiment, the joining region 100 has the frictional joining region 110 and the plastic deformation region 120, but the joining region 100 does not have to have the plastic deformation region 120. Furthermore, the joining region 100 between the fixing portion 41 and the small diameter portion 251 does not have to be a region formed by frictional joining as long as it suppresses movement of the fixing portion 41 in the press-fitting direction (inward D3).

[0073] A spiral joint is an example of a joint region 100 between the fixed portion 41 and the small diameter portion 251 that is not a friction joint. The spiral joint is formed, for example, by forming one of the fixed portion 41 and the small diameter portion 251 into a male screw shape and the other into a female screw shape, and inserting the cover member 4 into the pin hole 25 while spiraling it in the closing process.

[0074] It should be understood by those skilled in the art that various changes, substitutions, and alterations can be made to the present invention without departing from the scope of the present invention. For example, the above-described embodiments and modifications may be appropriately combined within the scope of the present invention.

[0075] 1, 10 Band 2 Link 25 Pin hole 251 Small diameter portion 252 Large diameter portion 4 Cover member 41 Fixing portion 42 Closing portion

Claims

1. A band comprising: a plurality of links extending in the width direction so as to penetrate two adjacent links, and each link having a pin hole formed therein, the pin hole including a small diameter portion and a large diameter portion connected to the outside of the small diameter portion in the width direction and having an inner diameter larger than that of the small diameter portion; and a cover member having a fixing portion and a blocking portion connected to the fixing portion and formed so that its outer diameter decreases toward the fixing portion, wherein the fixing portion abuts against the inner wall of the small diameter portion to fix the cover member to the pin hole, and the blocking portion blocks the outer end of the large diameter portion.

2. The band according to claim 1, wherein the fixing portion is formed in a columnar shape having a uniform outer diameter.

3. The band according to claim 1, wherein the fixing portion is formed in a tapered shape having a smaller taper angle than the closing portion.

4. The band as described in claim 1, further comprising: a frictional bonding region formed in the bonding region between the fixed portion and the small diameter portion, where the piece and the cover member are frictionally bonded; and a plastic deformation region formed in the bonding region between the closing portion and the large diameter portion, where the piece and the cover member are plastically deformed.

5. The band according to claim 4, wherein the plastic deformation region further has a protruding portion that is connected to the frictional bonding region and protrudes outward from the frictional bonding region in the radial direction of the cover member.

6. A band as claimed in any one of claims 1 to 5, wherein the cover member is made of the same material as the links.

7. A band according to claim 6, wherein said material is titanium.

8. A method for manufacturing a band formed by connecting a plurality of links to each other, comprising: a preparation step of preparing a band having a pin hole extending in the width direction of the band, the pin hole having a small diameter portion and a large diameter portion connected to the outside of the small diameter portion in the width direction and having an inner diameter larger than that of the small diameter portion; an arrangement step of arranging a cover member having a fixing portion and a blocking portion connected to the fixing portion and formed so that its outer diameter decreases toward the fixing portion, outwardly of the pin hole in the width direction; and a blocking step of displacing the cover member inwardly in the width direction to block the pin hole, wherein in the blocking step, the fixing portion abuts against an inner wall of the small diameter portion to fix the cover member to the pin hole, and the blocking portion blocks the outer end of the large diameter portion.

9. The method according to claim 8, wherein in the closing step, the lid member is press-fitted into the pin hole to press-fit the fixing portion against the inner wall of the small diameter portion.

10. The method according to claim 8, further comprising, after said closing step, a removing step of removing a portion of said lid member that protrudes outward in said width direction from said band.

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