JPH0852011A - Hook structure of integrally molded surface fastener - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To obtain a smooth feel similar to a woven type surface fastener at the time of engaging and releasing, and with a high engaging rate, together with a flat base material having sufficient repeating strength and durability. Provided is a novel hook structure of a molded surface fastener engaging member that is integrally molded. SOLUTION: A large number of hook pieces (2,20) integrally formed on the surface of a flat substrate (1) have a back surface (23,213) rising from the substrate (1) while inclining on a smooth curve, A rising part (21, 211) having a front surface (24, 214) rising up and a side surface,
Reinforcing ribs (3, 21 ', 30) having an appropriate cross-sectional shape are integrally formed on at least the side surfaces of the rising portions (21, 211) and have hook-shaped engaging portions (22, 212) extending forward from the tips thereof. There is.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention uses a thermoplastic resin,
Regarding an engaging member for a surface fastener obtained by integrally molding a flat base material and a large number of hook pieces by extrusion or injection,
More specifically, the present invention relates to a hook piece structure that has the flexibility and toughness of a monofilament even though it is a hook piece obtained by molding, improves the engagement rate, and prevents the base material from tearing. (Prior Art) As a surface fastener having a hook piece, one in which a monofilament is woven into a woven fabric and a part thereof is cut to form a hook piece has been known for a long time. This type of surface fastener is characterized in that the flexibility peculiar to the woven fabric and the flexibility of the monofilament are mixed, and the feel at the time of engaging / disengaging with the mating loop is extremely smooth. Moreover, since the monofilaments that make up the hook have undergone a drawing process, they have excellent tensile strength and bending strength even with a small cross-sectional area, and depending on the fabric structure, the hook group can be formed with extremely high density. Therefore, the engagement rate is high and it can withstand repeated use sufficiently. However, since this woven type surface fastener consumes a large amount of material and requires multiple steps, it is difficult to reduce the manufacturing cost. The surface fastener developed there is an integrally-molded surface fastener in which the base material and the hook piece are integrally molded at the same time by extrusion or injection.
A molding technique for this type of surface fastener is, for example, Japanese Patent Publication No. 48.
No. 22768, Japanese Utility Model Laid-Open No. 56-20509,
U.S. Pat. No. 3,312,583, Japanese Patent Publication No. 1-5017
No. 75, etc. For example, actual development Sho 56-205
According to the technology disclosed in Japanese Patent Publication No. 09-09, a flat base material and linear protrusions forming a large number of hook pieces are integrally molded, and then a metal mold having other prepared hemispherical grooves for hook molding is prepared. The hook is formed at the tip of the protrusion by deforming and fixing along the groove surface while pressing the tip of the protrusion into the groove. In this case, the direction of the hook portion at the tip to be formed becomes random, the direction of the engaging force with the mating engaging member is lost, and strong surface joining is obtained. However, in this method, it is difficult to align the tip of the linear protrusion and the groove, and since the hook shape is not formed at the same time in one step, the manufacturing process becomes complicated and it is not always necessary for each hook. Since the desired directionality cannot be obtained, and it is difficult to obtain a set hook shape, the hook shape after molding is poor in uniformity, and the engagement itself with the mating engaging member becomes uncertain, The current situation is that it has not been put to practical use. Also, for example, Japanese Patent Publication No.
In the techniques disclosed in Japanese Patent No. 2768 and Japanese Patent Publication No. 52-37414, the base portion and the hook portion are simultaneously molded integrally by extrusion, and continuous molding is possible. The molding method is that a large number of mold discs and spacer plate materials are alternately stacked to form a drum shape, and a thermoplastic resin in a molten state is extruded onto the rotating drum surface to form a cavity for a hook of the mold disc. After the resin is pushed in, the resin coated on the drum surface is pressed to form the base portion, and then cooled, and then the spacer plate material is retracted in the diameter reducing direction,
After that, the strip-shaped fastening member that has been molded is continuously peeled off from the drum surface. The mold disc has a large number of hook-shaped cavities extending from the peripheral surface toward the center on one side surface thereof at predetermined intervals in the circumferential direction, and the side surface of the spacer plate material is a smooth surface. There is.
On the other hand, the above-mentioned US Pat. No. 3,321,583,
Regarding the molding technique disclosed in Japanese Patent Publication No. 1-501775, although the means for pushing the resin into the hook-shaped cavity is different, both of them have the spacer plate material fixed and the inside of the cavity is integrally molded. The hook is pulled out together with the base portion from the surface of the drum in accordance with the rotation of the drum, and both the structure of the device and the manufacturing means are simplified as compared with the molding technique of Japanese Patent Publication No. 48-22768. Here, the reason why the plate material for the spacer is required is that the entire shape of the hook cannot be formed as a cavity in one mold due to the shape of the hook itself, and the spacer must be formed in the direction. This is because. Therefore,
The direction of the molded hook naturally has directionality. In order to eliminate this directional property, an integrally-molded type fastening member in which the tip of the hook piece is formed into a spherical shape is also known. (Problems to be solved by the invention) However, in the case of a hook-and-loop fastener engaging member of the type in which the base material and the hook piece are integrally formed as described above, both are of the woven type because of the technical difficulty of the die processing. Not only cannot such a delicate shape be obtained, but since the hook piece has poor molecular orientation, the hook piece has extremely low strength with the same thickness as the hook piece made of the monofilament described above, and cannot be put to practical use at all. As a result, in order to secure the desired strength, the size of each hook piece inevitably has to be increased, which not only makes it rigid, but also the number of hooks per unit area (hook piece density). Is reduced and the engagement rate with the mating loop material is reduced. In order to supplement this low engagement rate and increase the holding strength of the engaging portion, the tip engaging portion of the hook piece also has rigidity. Therefore, it has a hard feel when engaging and disengaging, and it also damages and cuts the mating loop material, resulting in extremely low durability, so it is not usually used repeatedly, for example, when installing interior materials. It is only done. This tendency is particularly remarkable in the case of the hook structure disclosed in Japanese Patent Publication No. 48-22768. That is,
For convenience of taking out the molded product, the tip cross section of the hook piece has a triangular cross section with a downward apex, and as a result, engagement with the mating loop material is performed at the apex of the triangular cross section. , The loop material will be easily cut.
In that respect, the hook structure disclosed in the above-mentioned U.S. Pat. No. 3,321,583 does not necessarily have to have a triangular cross section due to the molding method, and the loop material is less damaged. However, in the above hook structure obtained by integral molding, the side surface shape of the rising portion is simple and it is easy to fall from the root. As a result, when it is repeatedly used, it does not return to its original posture, and the engagement rate with the loop material decreases. On the other hand, as with the hook structure disclosed in Japanese Utility Model Laid-Open No. 56-20509, the hook portion at the tip of the hook piece has a circular cross section and is formed in an arc shape as in the case of the fabric type hook. When trying to obtain smoothness, not only is the hook difficult to engage with the hook because the hook piece rises vertically, but also when the tip hook part is pulled up by the loop during peeling, the hook-shaped part rises from the rising part of the hook piece. It deforms centering on the part that shifts to the engaging part, and it is easy to cut at that part, and it remains deformed even if it is not damaged, and the product value is impaired. Further, what can be commonly said in this type of integrally molded surface fastener is that the flat plate-shaped base material on which the hook pieces are integrally erected upright easily breaks between the respective hook piece rows. . As a result, they often cannot withstand repeated use. The present invention has been made for the purpose of eliminating the above-mentioned drawbacks of a conventional surface fastener in which a base material and a hook piece are integrally molded, particularly, the drawbacks based on the hook structure thereof. An object of the present invention is to provide a novel hook structure which has the same smooth feel as a woven type surface fastener, has a high engagement rate, and has sufficient repeating strength and durability. (Means for Solving the Problems) In order to achieve the above object, in a hook-and-loop fastener engaging member formed by integrally molding a large number of hook pieces on the surface of a flat substrate, the hook pieces are: The base material has a rear surface that slopes up on a smooth curve, a rising portion that has a front surface and side surfaces that rise upward, and a hook-shaped engaging portion that extends forward from the tip of the base material. The main structure is that the area is gradually increased, and at least the side surface of the rising portion is integrally formed with a reinforcing rib having an appropriate cross-sectional shape, and further, in the same hook row, the tip of the hook-shaped engaging portion is formed. And the inclined start ends of the rising portions of the adjacent hook pieces are positioned substantially on the same perpendicular line, or between the hook rows of two rows where the reinforcing ribs are adjacent to each other. Those formed by connecting the rising portion of the piece. (Function) The rising portion of the hook piece is erected upward on the front side and tilted on the back side, and the reinforcing rib is formed on the side surface thereof, and the tip is configured as a hook-shaped engaging portion,
Furthermore, since the rising portion has a gradually increasing cross-section toward the root, the hook-shaped engaging portion does not flex locally during peeling,
A force at the time of deformation acts on the entire hook piece, the damage of the engaging portion is prevented, and at the same time, the force is received by the root of the thickest rising portion, which enables smooth peeling. Further, the presence of the reinforcing rib prevents the hook piece from falling sideways, and when engaged, the mating loop member is guided to the engaging portion of the hook piece adjacent to the rear side along the inclination of the back side of one hook piece. In combination with the insertion, the engagement rate is improved and the engagement strength is increased. In particular, when arranging the tip of the engaging portion of the hook piece and the inclined start end of the hook piece in front of it on substantially the same vertical line,
The engagement rate is further increased. Further, by connecting adjacent hook pieces between the hook piece rows via the reinforcing rib, the strength of the rising portion of the hook piece is further increased and the flat base material is also prevented from being torn. (Example) Hereinafter, the present invention will be specifically described based on illustrated examples. FIG. 1 is a partial side view of a surface fastener showing a typical hook structure of the present invention. In the figure, 1 is a plate-shaped base material, and a large number of hook pieces 2 are provided on the top surface of the base material 1.
Are provided upright on the same row, and a large number of these hook rows are provided in parallel. In the example of FIG. 1, two rows of hooks A and B are shown, and the hook pieces 2 in each of the rows of hooks A and B are reversed by 180 °. The base material 1 and the hook piece 2 are obtained by integrally molding the thermoplastic resin using the above-mentioned extrusion molding or injection molding. The hook structure according to the present embodiment is similar to the shape of a wave front hitting from the side as shown in the drawing, and the rising portion 21 from the base material 1 and the downward hook-like engagement formed at the tip of the rising portion 21. It is composed of the unit 22. A surface of the rising portion 21, which is opposite to a direction in which the hook-shaped engaging portion 22 is formed, that is, a back surface 23 is inclined and rises on a smooth curve from the surface of the base material 1, and the engaging portion 22 is also formed.
The surface in the forming direction, that is, the front surface 24, rises from the substantially vertical portion toward the surface of the base material 1 via a radius, and the overall shape of the rising portion 21 as viewed from the side surface is a divergent shape toward the bottom. ing. Further, on the side surface of the rising portion, a reinforcing rib 21 'which is the most important feature of the present invention is integrally formed with the base material 1. The shape and size of the reinforcing rib 21 'are appropriately determined, and a typical shape thereof is shown in FIGS. 2 and 3.
The rib shape of FIG. 2 has substantially the same width in the height direction when viewed from the front of the hook. The rib shape in FIG. 3 is
The width is gradually reduced from the base material 1 upward. At the upper end of the rising portion 21, a hook-like engaging portion 22 having an engaging space 25 below is formed following each tangent line of the rear surface 23 and the front surface 24 thereof. Further, the hook-shaped engaging portion 22 is designed to be slightly tapered, and therefore, from the tip 26 of the hook-shaped engaging portion 22 to the root 2 of the rising portion 21.
The cross-sectional area gradually increases toward 7. In such a structure, when a loop member, which is a mating engaging member (not shown), is pressed toward the hook piece 2 in order to engage the hook-and-loop fastener, the loop member is hooked to the inclined rear surface 23 side of the rising portion 21 and the hook. Top end 2 of the linear engagement portion 22
The loop material distributed to the 6 side and guided on the back surface 23 engages with the hook-like engagement 22 of the hook pieces 2 adjacent to the back surface side, and is guided in the direction of the tip 26 of the hook upper engaging portion 22. Engages with the engaging portion 22 as it is, and in any case, the engagement rate is significantly increased. In particular, in the embodiment shown in FIG. 1, the tip 26 of the hook-shaped engaging portion 22 and the rear surface starting end 28 of the rising portion 21 of the hook piece 2 adjacent in front of the hook-shaped engaging portion 22 are arranged on substantially the same vertical line, The engagement rate of the loop material guided to the 23 side is further increased. Further, the presence of the reinforcing rib 21 'prevents the hook piece 2 from falling sideways when the loop material is pressed, and the engagement rate with the loop material does not decrease even after repeated use. On the other hand, when the hook-and-loop fastener is peeled off, since the hook-shaped engaging portion 22 is tapered, the engaging portion 22 is more flexible toward the tip, so that the loop material can be smoothly removed. Due to the above-described structure of the rising portion 21, even if an excessive peeling force acts on the hook-shaped engaging portion 22, the same action is reliably received at the root, and the rising portion 21 is deformed in the upright direction as a whole, and the loop is formed. Is quickly disengaged from the engaging portion 22. In the present invention, the reinforcing rib 2 is provided between the adjacent hook piece rows A and B as shown in FIGS.
1'can be separated from each other, but preferably between the adjacent hook piece rows A and B, the reinforcing rib 21 'is provided.
Are connected to each other. FIG. 6 shows a hook piece 2 in which reinforcing ribs 3, 3, ...
The modification of 0 is shown. In the case of this example, the hook piece 20
Is particularly prone to fall sideways, so that between the adjacent hook piece rows, the rising portions 21 of the hook pieces are reinforced with each other by the reinforcing ribs 3.
3, ... are connected together. This reinforcement rib 3,
The presence of 3, ... increases the strength of the entire rising portion 21, so that the other portion of the hook piece 20 can be made thinner, and therefore,
The other density of the hook pieces 20 can be increased to that extent, and the hook piece 20 can be made closer to a woven type surface fastener. It goes without saying that the reinforcing ribs 3, 3, ... Connected integrally are not limited to the illustrated examples, but the reinforcing ribs 3, 3 of the same kind integrally connected to the molded surface fastener of this kind.
When 3, ... Is applied, the flat base material is further prevented from being easily torn between the hook piece rows A and B. In the example shown in FIGS. 7 and 8, the rising portions 211 of the hook pieces 20 are substantially upright except for the back surface 213, the height of the reinforcing ribs 30 is set high, and the distance between the adjacent hook pieces 20, 20 is increased. It is narrowing. this is,
Due to the presence of the reinforcing ribs 30, the thickness of the hook pieces 20 can be reduced, so that it is possible to bring the two pieces closer to each other to increase the density of the hook pieces and to improve the insertability of the engaging portion 212 into the loop. This is because, even if the front surface 214 of the rising portion 211 is upright, there is no concern about disconnection of the hook-shaped engaging portion 212. (Effect of the invention) Since the present invention is configured as described in detail above, even in the case of an integrally molded type surface fastener, the unique hook structure improves the engagement rate with the mating loop material, In addition, when peeling, the loop material can be removed smoothly, and even if there is an instantaneous resistance, the force is received locally and deformed as a whole, so there is no damage to the engaging part, especially reinforcement. The presence of the ribs makes it possible to withstand repeated use of the hook-and-loop fastener.
There is no hardness when peeled, and a smooth feel similar to that of a woven type surface fastener can be obtained. Furthermore, when connecting the rising portions of adjacent hook pieces between rows with reinforcing ribs, there is no tearing of the flat base material between the rows of hook pieces, and the insertion performance into the mating loop material increases accordingly. The hook piece density can be increased, the strength that can be practically used is ensured, and the performance is closer to that of the woven type surface fastener.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial side view showing a cross section of a part of an integrally molded type surface fastener showing a hook structure which is a typical embodiment of the present invention, and FIG. Part front view, FIG. 3 is a partial front view showing another example of a surface fastener, FIG. 4 is a view taken in the direction of arrow II of FIG. 1, FIG. 5 is a view taken in the direction of arrow III-III of FIG. 1, and FIG. FIG. 7 is a partial plan view of a surface fastener showing another modified example, FIG. 7 is a partial side view showing another modified example, and FIG.
The figure is a partial plan view of the same surface fastener. Description of main parts of the drawing 1 ... Base material 2, 20 ..... hook pieces 21, 211 ..... rising portions 22, 212 ..... hook-shaped engaging portions 23, 213. ...... Rear surface 24, 214 ………… Shaft 25 …………………… Engaging space 26 ……………… (Engaging part) Tip 27 ……………… (Rising part) Root 28… ……………… (Rising part) Rear-ends 21 ′, 30 ………… Reinforcing ribs A, B ……………… Hook row

Claims (1)

[Claims] 1. A large number of hook pieces (2, 2) are formed on the surface of the flat substrate (1).
0) is formed by integral molding, and the hook piece (2, 20) has a back surface (23, 213) rising from the base material (1) while inclining on a smooth curve. ), The front surface that rises upward (24, 2
14) and rising parts (21, 211) having side faces
And a hook-shaped engaging part (22,
212), and the cross-sectional area of the rising portion (21, 211) is gradually increased toward the root thereof, and the reinforcing rib (3, 21 ′) having a proper cross-sectional shape at least on the side surface of the rising portion (21, 211). , 30) are integrally formed so as to project. A hook piece structure for an integrally molded surface fastener. 2. In the same hook piece row (A or B), the tips (26) of the hook-shaped engaging portions (22, 212) and the rising portions (21, 2) of the adjacent hook pieces (2, 20).
The hook piece structure according to claim 1, wherein the inclined starting ends (28) of (11) are located substantially on the same vertical line. 3. The reinforcing ribs (3, 21 ′, 30) are connected between the rising portions (21, 211) of the adjacent hook pieces (2, 20) between at least two adjacent rows (A, B). The hook piece structure according to claim. 4. The hook piece structure according to claim 1, wherein the reinforcing ribs (3, 21 ', 30) gradually increase in cross-sectional area from the upper end to the root.