Snap fastener installation machine

Abstract

To provide a snap fastener attaching machine capable of preventing the occurrence of molding defects such as a protrusion of a rivet member not breaking through a sheet-like member and cracking of the rivet member or fitting member. [Solution] A snap fastener installation machine in which a sheet-like member 3 is placed between a rivet member 1 held by a lower fixture 4 and a fitting member 2 held by an upper fixture 5, and the two fixtures 4, 5 are brought close to each other, the protrusion 1a of the rivet member 1 breaks through the sheet-like member 3 and penetrates the through hole 2a provided in the center of the fitting member 2, and the tip of the protrusion 1a is struck with a crimping punch 6 equipped on the upper fixture 5, causing it to expand and deform, thereby crimping the rivet member 1 and fitting member 2 together with the sheet-like member 3 sandwiched between them; after the protrusion 1a of the rivet member 1 breaks through the sheet-like member 3, it enters the through hole 2a of the fitting member 2, but the sheet-like member 3 does not enter the through hole 2a.

Description

[Technical Field]

[0001] The present invention relates to a snap fastener installation machine used to attach snap fasteners (plastic snaps and the like) to sheet-like members such as fabrics. [Background technology]

[0002] As shown in Figures 4, 5(A), and 5(B), a conventional snap fastener installation machine is configured such that when a sheet-like member 3 is placed between a rivet member 1 held by a lower fixture 51 and a fitting member 2 held by an upper fixture 52 and the two fixtures 51 and 52 are brought close to each other, the protrusion 1a of the rivet member 1 breaks through the sheet-like member 3 and penetrates the through-hole 2a provided in the center of the fitting member 2, and the tip of the protrusion 1a is struck by a crimping punch 53 attached to the upper fixture 52, causing it to expand and deform, thereby crimping the rivet member 1 and the fitting member 2 together with the sheet-like member 3 sandwiched between them to form a snap S (Patent Document 1).

[0003] Here, the lower fixture 51 holds the rivet member 1 with the protrusion 1a facing upward and includes a receiving portion 54 that is slidable in the vertical direction, and a biasing means 55 that biases the receiving portion 54 upward. The upper fixture 52 includes an annular holding portion 56 that detachably holds the fitting member 2, and a crimping punch 53 that is slidable along a slide hole 57 that extends in the vertical direction on the radially inner side of the holding portion 56.

[0004] 4, 5(A) and 5(B) show the manufacturing process of the female snap S1 in which the fitting member 2 is female, but as shown in FIGS. 5(C) and 5(D), the male snap S2 in which the fitting member 2 is male is also manufactured in the same way, and the female snap S1 and the male snap S2 can be connected by fitting the male and female fitting members 2 together as shown in FIG. 5(E). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Utility Model Registration No. 3197042 Summary of the Invention [Problem to be solved by the invention]

[0006] Currently, snap fasteners are primarily made of POM (polyacetal), and these snap fasteners can be stably attached using the conventional snap fastener attachment machine. However, if the snap fastener is made of a different material (such as nylon, polyester, ABS resin, polyethylene, or polypropylene) that is weaker than POM, attachment using the conventional snap fastener attachment machine will result in molding defects, such as the protrusion 1a of the rivet member 1 not breaking through the sheet-like member 3 or the rivet member 1 or the fitting member 2 cracking.

[0007] As shown in the enlarged view in the upper right of Figure 4, when the protrusion 1a of the rivet member 1 breaks through the sheet-like member 3, it acts to pull the sheet-like member 3 into the through hole 2a of the fitting member 2. This pulling action is thought to be a factor in generating large resistance when the protrusion 1a breaks through the sheet-like member 3, and a factor in making it easier for the impact of the crimping punch 53 on the protrusion 1a to be transmitted as an impact to parts of the rivet member 1 other than the protrusion 1a and to the fitting member 2, resulting in the above-mentioned molding defects.

[0008] The present invention was made with the above points in mind, and its purpose is to provide a snap fastener installation machine that can prevent molding defects such as the protrusions of the rivet member not breaking through the sheet-like member, or molding defects such as the rivet member or mating member cracking. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the snap fastener installation machine of the present invention is a snap fastener installation machine in which, when a sheet-like member is placed between a rivet member held by a lower fixture and a mating member held by an upper fixture and the two fixtures are brought close to each other, the protrusion of the rivet member breaks through the sheet-like member and penetrates the through hole provided in the center of the mating member, and the tip of the protrusion is struck with a crimping punch equipped on the upper fixture to expand and deform the diameter, thereby crimping the rivet member and the mating member together with the sheet-like member sandwiched between them, and is configured so that after the protrusion of the rivet member breaks through the sheet-like member, it enters the through hole of the mating member, but the sheet-like member does not enter the through hole (Claim 1).

[0010] In the above snap fastener installation machine, the lower mounting fixture comprises a receiving part that holds the rivet member with its protrusion facing upward, a sliding tube that is arranged radially outside the receiving part so as to be slidable in the vertical direction and whose upper end in its natural state is closer to the upper end than the lower end of the rivet member held in the receiving part, and a biasing means that biases the sliding tube upward, and the upper mounting fixture comprises an annular holding part that releasably holds the fitting member, a crimping punch that is slidable along a sliding hole that extends vertically radially inside the holding part, and a pressing tube that is arranged radially outside the holding part and is made of an elastic material that protrudes below the fitting member held in the holding part and can abut against the upper end of the sliding tube via a sheet-like member, and the upper mounting fixture may be configured so that when the sliding tube and the pressing tube are brought closer together from a state in which they abut via the sheet-like member, the protrusion of the rivet member breaks through the sheet-like member and then enters the through-hole of the fitting member (Claim 2). [Effects of the Invention]

[0011] The present invention provides a snap fastener installation machine that can prevent molding defects such as the protrusions of the rivet member not breaking through the sheet-like member, or molding defects such as the rivet member or fitting member cracking.

[0012] In other words, in the snap fastener installation machine of the invention according to each claim of the present application, the protrusion of the rivet member does not pull the sheet-like member into the through hole of the mating member when it breaks through the sheet-like member, thereby preventing molding defects caused by this pulling.

[0013] In the snap fastener installation machine of the invention according to claim 2, by using a pressure tube or the like, it is possible to reliably prevent the occurrence of the above-mentioned molding defects. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is an explanatory view (longitudinal cross-sectional end view) showing the schematic configuration of a snap fastener attaching machine according to one embodiment of the present invention; [Figure 2] 4 is an explanatory view (longitudinal cross-sectional end view) showing the first half of the snap fastener attaching process using the snap fastener attaching machine. FIG. [Figure 3] 10 is an explanatory view (longitudinal cross-sectional end view) showing the latter half of the snap fastener attaching process using the snap fastener attaching machine. FIG. [Figure 4] FIG. 1 is an explanatory diagram illustrating the configuration of a conventional snap fastener attaching machine. [Figure 5] (A) and (B) are explanatory diagrams showing the process of attaching a female snap, (C) and (D) are explanatory diagrams showing the process of attaching a male snap, and (E) is an explanatory diagram (longitudinal cross-sectional end view) showing the state in which the female snap and male snap are connected. DETAILED DESCRIPTION OF THE INVENTION

[0015] The embodiments of the present invention will be described below.

[0016] The snap fastener installation machine shown in Figure 1 is designed so that when a sheet-like member 3 is placed between a rivet member 1 held by a lower fixture 4 and a mating member 2 held by an upper fixture 5 and the two fixtures 4, 5 are brought close to each other, the protrusion 1a of the rivet member 1 breaks through the sheet-like member 3 and penetrates the through hole 2a provided in the center of the mating member 2, and the tip of the protrusion 1a is struck by a crimping punch 6 provided on the upper fixture 5, causing it to expand and deform, thereby crimping the rivet member 1 and the mating member 2 together with the sheet-like member 3 sandwiched between them.This machine is designed to perform well not only when the snap fastener is made from POM, but also when it is made from materials that are weaker than POM (such as nylon, polyester, ABS resin, polyethylene, polypropylene, etc.).

[0017] In the following, we will explain the case where the engaging member 2 is female (similar to the engaging member 2 in Figures 4(A) and (B)), but this explanation also applies to the case where a male engaging member 2 (similar to the engaging member 2 in Figures 4(C) and (D)) is used instead of a female one, so we will omit the explanation.

[0018] The lower mounting fixture 4 comprises a receiving portion 7 that holds the rivet member 1 with the protrusion 1a facing upward, a slide tube 8 that is arranged radially outside the receiving portion 7 and can slide up and down, and whose upper end in its natural state is located closer to the upper end than the lower end of the rivet member 1 held (placed) on the receiving portion 7, and a coil spring (an example of a biasing means) 9 that biases the slide tube 8 upward.

[0019] The receiving portion 7 has a cylindrical small diameter portion 10a, an intermediate portion 10b, and a large diameter portion 10c, in that order, from bottom to top, and is formed concavely on the upper end surface of a columnar core block 10, which gradually becomes thicker from bottom to top.

[0020] The sliding cylinder 8 has a cylindrical main body portion 8a that can slide up and down along the outer peripheral surface of the large diameter portion 10c, a cylindrical lower portion 8b that can slide up and down along the outer peripheral surface of the intermediate portion 10b, and a disc-shaped connecting portion (step portion) 8c that connects the main body portion 8a and the lower portion 8b.

[0021] An outer block 11 is provided on the outer peripheral side of the core block 10. The outer block 11 has a cylindrical small diameter portion 11a and a large diameter portion 11b that is connected to the upper side of the small diameter portion 11a and has an outer diameter larger than that of the small diameter portion 11a, and the small diameter portion 10a of the core block 10 is inserted into a shaft portion that extends from the small diameter portion 11a to the large diameter portion 11b of the outer block 11. The upper portion of the large diameter portion 11b is cylindrical, and the middle portion 10b and large diameter portion 10c of the core block 10 and the slide cylinder 8 can be accommodated in the inner space 11c.

[0022] In addition, a step 11d is formed in the center of the bottom of the space 11c, which can accept the lower end of the middle part 10b of the core block 10.With the lower end of the middle part 10b accepted in this step 11d, a retaining member 12, for example a C-ring, is engaged in a groove 10d provided at the bottom of the small diameter part 10a of the core block 10, thereby fixing the core block 10 and the outer block 11 together.

[0023] The coil spring 9 is disposed within the space 11c between the connecting portion 8c of the slide cylinder 8 and the bottom surface of the space 11c, and the slide cylinder 8 is biased upward by the coil spring 9 such that, in a natural state, the connecting portion 8c abuts against the large diameter portion 10c of the core block 10. The inner diameter of the coil spring 9 is larger than the outer diameter of the large diameter portion 10c of the core block 10, and the outer diameter of the coil spring 9 is smaller than the outer diameters of the main body 8a of the slide cylinder 8 and the connecting portion 8c.

[0024] The upper mounting fixture 5 includes an annular holding portion 13 that detachably holds the fitting member 2, a crimping punch 6 that can slide along a slide hole 14 that extends vertically on the radially inner side of the holding portion 13, and a pressing tube 15 that is provided radially outside the holding portion 13 and made of an elastic material (e.g., an elastomer such as urethane rubber or rubber) that protrudes downward beyond the fitting member 2 held by the holding portion 13 and can abut against the upper end of the slide tube 8 via the sheet-like member 3 (see Figure 2(B), etc.).

[0025] The holding portion 13 is formed in a state of protruding from the lower portion of a cylindrical guide block 16 which has a slide hole 14 and guides the crimping punch 6. Here, the fitting member 2 has a substantially disk-shaped base portion 2b with a through hole 2a formed in the center, and a cylindrical portion 2c which rises from the periphery of this base portion 2b and has an inner diameter which is at least one size larger than the outer diameter of the through hole 2a, and is configured so that the holding portion 13 engages with the inner peripheral surface of this cylindrical portion 2c.

[0026] The retaining tube 15 is attached to the guide block 16 by engaging with it. In this example, an annular flange 16a protruding outward is provided on the outer peripheral surface of the guide block 16, an annular engagement portion 16b having a smaller diameter than the annular flange 16a is provided below the annular flange 16a, and an annular groove 16c having a smaller diameter than the annular engagement portion 16b is provided between the annular flange 16a and the annular engagement portion 16b. In contrast, the retaining tube 15 has, from its upper end downward, an inward flange 15a whose inner diameter is approximately the same as the outer diameter of the annular groove 16c, an annular groove 15b whose inner diameter is approximately the same as the outer diameter of the annular engagement portion 16b, and a cylindrical main body portion 15c whose inner diameter is smaller than that of the inward flange 15a. When the upper surface of the retaining tube 15 is abutted against the lower surface of the annular flange 16a, the inward flange 15a fits into the annular groove 16c and the annular engagement portion 16b fits into the annular groove 15b, thereby engaging the retaining tube 15 with the guide block 16.

[0027] The guide block 16 is attached to the crimping punch 6 by a generally cylindrical connecting tube 17 made of an elastic material (for example, an elastomer such as urethane rubber or rubber). The crimping punch 6 has, from bottom to top, a generally cylindrical punch portion 6a, a neck portion 6b having a larger diameter than the punch portion 6a, and a head portion 6c having a larger diameter than the neck portion 6b, in that order, with an annular groove 6d formed in the upper part of the neck portion 6b. Furthermore, above the annular flange 16a of the guide block 16, a generally cylindrical protrusion 16d having an outer diameter approximately the same as that of the neck portion 6b of the crimping punch 6 is formed, and below the protrusion 6d is formed an annular groove 16e having an outer diameter approximately the same as that of the annular groove 6d of the crimping punch 6. The inner diameter of the connecting tube 17 is approximately the same as that of the annular grooves 6d, 16e, and the neck portion 6b of the crimping punch 6 is inserted (engaged) into the upper end of the connecting tube 17, and the protrusion portion 16d of the guide block 16 is inserted (engaged) into the lower end, thereby connecting the crimping punch 6 and the guide block 16 via the connecting tube 17.

[0028] Next, a method for attaching a snap fastener using the snap fastener attaching machine of this embodiment will be described.

[0029] First, as shown in FIG. 2(A), the rivet member 1 is held by the receiving portion 7 of the lower fixture 4, and the fitting member 2 is held by the holding portion 13 of the upper fixture 5.

[0030] Next, as shown in Fig. 2(B), the sheet-like member 3 is placed between the rivet member 1 held by the lower fixture 4 and the fitting member 2 held by the upper fixture 5. When the fixtures 4 and 5 are brought closer to each other in this state, as shown in Fig. 2(C), the fixtures 4 and 5 come into contact via the sheet-like member 3. When the fixtures 4 and 5 are brought even closer in this state, the pressing cylinder 15 bends and bulges outward, pushing the slide cylinder 8 downward, as shown in Fig. 2(D). As a result, the protrusion 1a of the rivet member 1 breaks through the sheet-like member 3.

[0031] As the two mounting fixtures 4 and 5 are brought even closer together, the protrusion 1a of the rivet member 1 penetrates the through hole 2a of the fitting member 2 from bottom to top, as shown in Figure 3(A). As shown in Figure 3(B), the tip of the protrusion 1a is struck with a crimping punch 6 (punch portion 6a) equipped on the upper mounting fixture 5, causing it to expand and deform, and the rivet member 1 and the fitting member 2 are crimped together with the sheet-like member 3 sandwiched in between (the snap S is completed).

[0032] Finally (after the snap S is completed), as shown in Figure 3(C), the two mounting fixtures 4 and 5 are simply moved apart from each other. This separation causes the rivet member 1 to separate from the receiving portion 7 in the lower mounting fixture 4, and the sliding tube 8 to return to its original natural state (see Figures 2(A) and (B)). In the upper mounting fixture 5, the fitting member 2 separates from the holding portion 13, and the bent retaining tube 15 returns to its original shape.

[0033] 2(B) from the lower end of the fitting member 2 held by the holding portion 13 to the lower end of the presser tube 15 attached to the guide block 16 is preferably 3 mm or more and 8 mm or less, and in this example is approximately 5 mm (4.5 mm to 5.4 mm). If the height difference is less than 3 mm, when the protrusion 1a of the rivet member 1 breaks through the sheet-like member 3 and then enters the through-hole 2a of the fitting member 2, the sheet-like member 3 will also easily enter the through-hole 2a. If the height difference is more than 8 mm, it may be difficult to pass the protrusion 1a of the rivet member 1 through the through-hole 2a.

[0034] The materials of the lower fixture 4 and the upper fixture 5 may be appropriately selected so as to be suitable for the above-mentioned operation.

[0035] In the snap fastener installation machine of this example configured as described above, the protrusion 1a of the rivet member 1 penetrates the sheet-like member 3 and then enters the through hole 2a of the fitting member 2, and the sheet-like member 3 is configured not to enter the through hole 2a, thereby preventing molding defects such as the protrusion 1a of the rivet member 1 not penetrating the sheet-like member 3, or molding defects such as the rivet member 1 or the fitting member 2 cracking.

[0036] In other words, in the snap fastener installation machine of this example, the protrusion 1a of the rivet member 1 does not pull the sheet-like member 3 into the through hole 2a of the fitting member 2 when it breaks through the sheet-like member 3, thereby preventing molding defects caused by this pulling.

[0037] In addition, in the snap fastener installation machine of this example, by using a retaining tube 15 or the like that protrudes downward from the engaging member 2 when held by the holding portion 13, it is possible to reliably prevent the occurrence of the above-mentioned molding defects.

[0038] The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and scope of the present invention. For example, the following modifications can be made:

[0039] The snap fastener installation machine may be configured so that only the upper fixture 5 moves up and down (raise and lower) (the lower fixture 4 is fixed), but this is not limiting, and it may also be configured so that only the lower fixture 4 or both fixtures 4 and 5 move up and down (raise and lower).

[0040] It goes without saying that the modifications given in this specification may be combined as appropriate. [Explanation of symbols]

[0041] 1 Rivet member 1a protrusion 2 Fitting member 2a Through hole 2b Base part 2c Cylindrical part 3 Sheet-like members 4 Lower mounting bracket 5 Upper mounting bracket 6. Crimping punch 6a Punch section 6b Neck 6c head 6d Annular groove 7 Receiving part 8 Slide tube 8a Main body 8b lower part 8c Joint 9 Coil spring (biasing means) 10 Core Block 10a Small diameter section 10b middle part 10c Large diameter part 10d groove 11 Outer Block 11a Small diameter section 11b Large diameter part 11c Space 11d Stepped section 12 Stopper 13 Holding part 14 slide holes 15 Presser tube 15a Inward flange 15b Annular groove 15c Main body 16 Guide block 16a Annular flange 16b Annular engagement portion 16c Annular groove 16d protrusion 16e Annular groove 17 Connecting tube 51 Lower mounting bracket 52 Upper mounting bracket 53 Crimping punch 54 Receiving part 55 Actuation means 56 Holding part 57 Slide hole S Snap S1 Female Snap S2 Male Snap

Claims

1. A snap fastener installation machine in which, when a sheet-like member is placed between a rivet member held by a lower fixture and a fitting member held by an upper fixture and the two fixtures are brought close to each other, a protrusion of the rivet member breaks through the sheet-like member and penetrates a through-hole provided in the center of the fitting member, and the tip of the protrusion is struck by a crimping punch provided on the upper fixture to expand and deform the protrusion, thereby crimping the rivet member and the fitting member together with the sheet-like member sandwiched therebetween, A snap fastener installation machine configured such that after the protrusion of the rivet member breaks through the sheet-like member, it enters the through-hole of the fitting member, but the sheet-like member does not enter the through-hole.

2. The lower mounting fixture comprises a receiving portion that holds the rivet member with the protrusion facing upward, a slide tube that is provided radially outside the receiving portion and can slide up and down, and whose upper end in its natural state is located closer to the upper end than the lower end of the rivet member held in the receiving portion, and a biasing means that biases the slide tube upward, The upper attachment includes an annular holding portion that detachably holds the fitting member, a crimping punch that is slidable along a slide hole that extends vertically on the radially inner side of the holding portion, and a presser cylinder that is provided radially outside the holding portion, is made of an elastic material that protrudes downward beyond the fitting member held in the holding portion, and is capable of abutting against the upper end of the slide cylinder via a sheet-like member; 2. A snap fastener installation machine as described in claim 1, wherein when the slide tube and the presser tube are brought closer together from a state in which they are in contact via the sheet-like member, the protrusion of the rivet member breaks through the sheet-like member and then the protrusion enters the through hole of the fitting member.

Images