JP4517382B2 - Snap fastener synthetic resin female fitting - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, the surface of a substrate having a through-hole for inserting and inserting a protrusion of a rivet member into the center portion is formed in a substantially cylindrical shape from the substrate, and radially inward on the inner surface of the upper end portion. A female fitting portion (a concave portion that elastically fits with the male snap) having a bulging portion bulged to the upper end side of the female fitting portion and more than the bottom of the arc-shaped groove The present invention relates to a synthetic resin female fitting member of a snap fastener in which slits are formed at appropriate intervals in the circumferential direction at appropriate intervals.
[0002]
[Prior art]
FIG. 5 shows a synthetic resin female fitting member of a conventional snap fastener. In the figure, reference numeral 2a denotes a substrate having a through hole 1a formed in the central portion, 5a denotes a female fitting portion that rises from the substrate 2a in a substantially cylindrical shape, and 4a denotes an arcuate wall portion defined by a slit 3a. . As shown in FIG. 5, the female fitting portion 5 a has a bulging portion that bulges radially inward on the inner surface of the upper end portion.
[0003]
In the conventional synthetic resin female fitting member, as shown in the figure, the slit 3a is continuous from the radially inner end to the radially outer end of the arcuate wall 4a (in other words, the arcuate wall 4a). Therefore, the elastic fitting (snap action) with the male snap may become extremely loose.
[0004]
That is, when the female fitting portion 5a is formed in a complete cylindrical shape that is continuous over the entire circumference, it is difficult to elastically deform the female fitting portion 5a outward in the radial direction, and elastic fitting with a male snap ( The slit 3a is provided as shown in the figure because the snap action is too tight. However, when the slit 3a is provided, a part of the arcuate wall 4a irregularly extends radially outward at the time of manufacture. As a result, the inner diameter of the female fitting portion 5a becomes extremely larger than the design value, and the desired elastic fitting force may not be obtained.
[0005]
This is considered to be due to the following reason. That is, as shown in FIGS. 6 and 7, when the high-temperature liquid material resin b is injected into the injection mold a, the material resin b gradually cures due to the temperature difference from the mold a and is injected into the injection port. Since c bypasses the through-hole molding die portion d and wraps around in the opposite side and fills in the die a, the resin density is lower at the opposite side than the vicinity of the injection port c. Tend.
[0006]
Therefore, as shown in FIGS. 7 (a) and 7 (b), when the center of the substrate 2a is ejected by the demolding rod e, the entire female fitting portion 5a is simultaneously removed from the mold. Instead, the arc-shaped wall portion 4a near the injection port with a high resin density comes out with a delay from the portion having a low resin density (the arc-shaped wall portion 4a located on the side opposite to the injection port c). Therefore, the arc-shaped wall portion (the portion with low resin density) that comes out first receives resistance from the undercut portion of the mold and deforms outward in the radial direction as shown in FIG. The high arc-shaped wall part is removed without much resistance due to the undercut part of the mold, and the female wall is fitted by the amount of deformation of the arc-shaped wall part 4a having a low resin density. The inner diameter of the portion (the inner diameter of the recessed portion formed by all the arc-shaped wall portions) becomes larger than the design value, and the elastic fitting (snap action) with the male snap becomes extremely loose.
[0007]
[Problems to be solved by the invention]
The present invention has been made on the basis of the above-mentioned consideration results. When the mold is removed from the injection mold, the portion having a low resin density (the arcuate wall portion located on the side opposite to the injection port) has a radius. An object of the present invention is to provide a synthetic resin fitting member for a snap fastener that suppresses deformation outward in the direction, makes the inner diameter of the female fitting portion constant, and obtains the desired elastic fitting force. It is said.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the technical means taken by the present invention are as follows. That is, the feature of the synthetic resin female fitting member of the snap fastener according to the present invention is that a high temperature is introduced into the female fitting member molding space of the injection mold a from the injection port c formed at one end in the radial direction. The liquid material resin b is injected, and the material resin b bypasses the through-hole molding die portion d and moves to the opposite side. After the material resin b is cured, the female mold is cured in the mold a. the center of the substrate 2a in the fitting member poked in demolding rod e is prepared by demolding, the surface of the substrate 2a that the through-hole 1 is formed in the center portion, rising from the substrate 2a in a substantially cylindrical shape In addition, a female fitting portion 5 having a bulging portion bulging inward in the radial direction is formed on the inner surface of the upper end portion, and the rear surface of the female fitting portion 5 is partitioned into a plurality of pieces by radial ribs 6. and the arc-shaped groove 7 is formed, and the arcuate groove in the upper side of the female fitting part 5 Of a slit 3 in the circumferential direction suitable intervals in the position higher than the bottom, the upper end a plurality of arc-shaped wall portion a synthetic resin female fitting member odor was divided into 4 of the female fitting part 5 Te, the slit 3 has not reached to the radially outer end of the arc-shaped wall portion 4, the rising wall portion 8 connecting the to what arcuate wall portion 4 of the outer end sides of the slit 3 is formed, the slits 3 in that the outer end in the radial direction is closed by the rising wall 8 .
[0009]
According to the above configuration, since the radially outer end of the slit is blocked by the rising wall portion (in other words, the arc-shaped wall portion is not traversed in the radial direction, and the arc-shaped sides on the both sides are formed at the outer end of the slit. Since the rising wall portion that connects the wall portions remains), in the manufacturing process by injection molding, when removing the mold by moving the central portion of the substrate, the female fitting portion is far from the material resin injection port. Even if the arc-shaped wall (arc-shaped wall having low resin density) tries to escape from the mold preceding the arc-shaped wall on the opposite side (arc-shaped wall having high resin density), the arc-shaped walls As a result of the expansion being restricted by the rising wall portion, all the arc-shaped wall portions come out of the mold at the same time or almost simultaneously, and the outer shape caused by the arc-shaped wall portion at a specific position being removed in advance. The deformation to is suppressed.
Therefore, the inner diameter of the female fitting portion (the inner diameter of the recessed portion formed by all the arcuate wall portions) is not greatly deviated from the design value, and the desired elastic fitting force can be obtained.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to the drawings. A is a synthetic resin female fitting member of a snap fastener constituted by a female snap and a male snap, and B is a synthetic resin female fitting member. A rivet-like member made of synthetic resin that fastens A to a sheet-like member (for example, cloth for clothing) C. D is a male fitting member, and E is a rivet-like member for fixing the male fitting member D to the sheet-like member C.
[0011]
The synthetic resin female fitting member A is manufactured by injection molding as in the case of the conventional product, and is inserted into the center portion by inserting the protrusion of the rivet member B penetrating the sheet-like member C to be caulked. A circular substrate 2 having through holes 1 formed therein, and a plurality of arc-shaped wall portions 4 formed on the surface thereof by slits 3 rising from the substrate 2 in a substantially cylindrical shape and formed at appropriate intervals in the circumferential direction. And a female fitting portion (a concave portion that elastically fits with the male fitting portion of the male fitting member D) 5. An arcuate groove 7 partitioned into a plurality of radial ribs 6 arranged immediately below the slit 3 is formed.
[0012]
As shown in FIG. 3, the slit 3 is formed at a position higher than the bottom of the arc-shaped groove 7, and does not reach the radially outer end of the arc-shaped wall portion 4. For example, a rising wall portion 8 that does not cross the arcuate wall portion 4 in the radial direction and connects the arcuate wall portions 4 on both sides to the outer end of the slit 3 is formed. Reference numeral 9 denotes a spike-like protrusion for preventing slippage with respect to the sheet-like member C.
[0013]
According to the above configuration, since the rising wall portion 8 that connects the arcuate wall portions 4 on both sides remains at the outer end of the slit 3, the manufacturing by injection molding shown in FIGS. In the process, when the center portion of the substrate 1 is moved by the demolding rod e and demolded, an arcuate wall portion (a circle having a low resin density) far from the material resin injection port c in the female mold fitting portion 5. Even if the arcuate wall part 4 tries to escape from the mold prior to the arcuate wall part 4 (the arcuate wall part having a high resin density) 4 on the opposite side, the spread of the arcuate wall parts 4 becomes the rising wall part 8. As a result of the restraint, all the arcuate wall portions 4 come out of the mold simultaneously or substantially simultaneously, and the outward deformation caused by the demolding of the arcuate wall portion at a specific position is suppressed. Is done. Therefore, the inner diameter of the female fitting portion 5 (the inner diameter of the recessed portion formed by all the arcuate wall portions 4) is not greatly deviated from the design value, and an expected elastic fitting force can be obtained. .
[0014]
【The invention's effect】
Since the present invention has the above-described configuration, a portion having a low resin density (an arcuate wall portion located on the side opposite to the injection port) is deformed radially outward when demolding from the injection mold. Is suppressed, the inner diameter of the female fitting portion is made constant, and the desired elastic fitting force can be obtained.
[Brief description of the drawings]
FIG. 1 is a plan view of a synthetic resin female fitting member of a snap fastener according to the present invention.
FIG. 2 is a rear view of the synthetic resin female fitting member.
FIG. 3 is a sectional view of the synthetic resin female fitting member.
FIG. 4 is a cross-sectional view of a snap fastener configured using the synthetic resin female fitting member.
FIG. 5 is a cross-sectional view of a synthetic resin female fitting member showing a conventional example.
FIG. 6 is a diagram for explaining a problem of a conventional example.
FIG. 7 is a diagram for explaining a problem of a conventional example.
[Explanation of symbols]
A ... Synthetic resin-made female fitting member, 1 ... through hole, 2 ... substrate, 3 ... slit, 4 ... arc-shaped wall portion, 5 ... female fitting portion, 8 ... rising wall portion.

Claims (1)

A high temperature liquid material resin b is injected into a female fitting member molding space of the injection molding die a from an injection port c formed at one end in the radial direction, and the material resin b is used as a through hole molding die. The part d is detoured and turned to the opposite side, and after the material resin b is cured, the center of the substrate 2a in the female fitting member cured in the mold a is protruded by the demolding rod e and removed. On the surface of the substrate 2a having the through-hole 1 formed in the central portion, and having a bulging portion rising from the substrate 2a in a substantially cylindrical shape and bulging radially inward on the inner surface of the upper end portion. forming a female fitting part 5 on the back surface of the female fitting part 5, a plurality of arcuate grooves 7 partitioned into formed by radial ribs 6, the upper end side of the female fitting part 5 in and forming a slit 3 in the circumferential direction suitable intervals in the position higher than the bottom of the arcuate groove 7, the female The upper end of the engaging portion 5 Te plurality of arc-shaped wall portion a synthetic resin female fitting member odor was divided into 4, the slit 3 has not reached to the radially outer end of the arc-shaped wall portion 4, the slits 3 is formed with a rising wall portion 8 that connects the arcuate wall portions 4 on both sides, and the radially outer end of the slit 3 is closed by the rising wall portion 8. Synthetic resin female fitting member.

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