JPH06209808A - Buckle made of synthetic resin and its injection molding method and metallic die - Google Patents

Abstract

PURPOSE:To surely detain a belt, and also, to eliminate a fear that the belt loosens carelessly, in the buckle by which length of the belt can be adjusted. CONSTITUTION:In the buckle 10 having a supporting bar 50 for folding back a free end 81 side of a belt 80, and a pressure contacting detaining bar 60 for press-contacting each belt 80 in order to generate frictional force between each folded-back belt 80, having a gap between the supporting bar 50 and the pressure contacting detaining bar 60, and having the supporting bar 50 in the upper part of the pressure contacting/detaining bar 60, the tip 62 of the pressure contacting/-detaining bar 60 is positioned in the direction of the tip 21 of both side wall parts 20 from a position of the rear end 51 of the supporting bar 50.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buckle made of synthetic resin capable of adjusting the length of a belt used for bags such as rucksacks and life jackets, a molding method thereof and a molding die.

[0002]

2. Description of the Related Art Conventionally, as this type of buckle, there is a ladder type buckle 10 as shown in FIGS. As shown in FIG. 9, the conventional buckle 10 has a tip 2 of both side wall portions 20 so as to connect a pair of left and right side wall portions 20, 20.
The holding bar 30 is provided at the position 1. And presser bar 3
The fixed bar 40, the support bar 50, and the pressure contact locking bar 60 are sequentially arranged in parallel with 0 between the left and right side wall parts 20, and the fixed bar is
40, the support bar 50 and the pressure contact locking bar 60 on both side wall parts.
20 connected to each.

Next, a method of using the conventional buckle 10 will be explained. On the other hand, the end portion of the belt is fixed to the fixed bar 40, while the free end or the free end of another belt is press-contacted with the support bar 50. It is supported so that its length can be adjusted using the bar 60. In the following description, the case where two belts are used will be described as an example. First, the first belt 70
9 is fixed to the fixed bar 40 by folding back one end of the fixed bar 40 or winding one end thereof, as shown in FIG. Therefore, the buckle 10 is fixed to the end portion of the belt 70.

On the other hand, as shown in FIG. 9, the second belt 80 has its free end 81 along the lower surface 71 of the press contact locking bar 60 and is passed between the support bar 50 and the fixed bar 40. , Support bar
Fold it back so that it passes between 50 and the pressure contact locking bar 60, and further fold the end of the folded back end 61 of the pressure contact locking bar 60 and the belt.
Pull it out through the gap between the base end 82 of 80. Belt concerned
To adjust the length of 80, the free end 81 may be pulled out longer or shorter. For example, the free end of belt 80
When 81 is strongly pulled and the length of pulling out the free end 81 is increased, the length of the belt 80 on the base end portion 82 side becomes relatively short.

After pulling the free end 81 of the belt 80,
When the force applied to the free end 81 is released, due to the weight of the bags and the tension applied to both belts 70, 80, both belts 70,
80 is pulled in the opposite direction. Therefore, the belt 80 is shown in FIG.
As shown in, at the position of the pressure contact locking bar 60, the base end portion of the belt 80, which overlaps inside and outside, is pressed against the pressure contact locking bar 60, and overlaps particularly outside of the double overlapping belt 80. Tension is applied to the 82 side.

At this time, in the double-overlapping belt 80, the portion of the free end 81 side that directly contacts the pressure contact locking bar 60 is strongly pressed against the lower surface 61 of the pressure contact locking bar 60 and tension is applied. Outside base end 82 side and pressure contact locking bar
The portion of the belt 80 on the side of the free end 81 is sandwiched by 60. Therefore, the portion of the belt 80 on the free end 81 side is prevented from biting into the tip 62 of the press contact locking bar 60 and loosening the belt 80.

Further, conventionally, the above-mentioned ladder-type buckle is used.
In addition to 10, a two-piece type as shown in FIG. 10 is often used. Conventional two-piece buckle
Also in 10, the fixing bar 40 is provided on one female buckle 11 as shown in FIG. The other male buckle 12
The pressure contact locking bar 60 and the support bar 50 are provided on the end of the pressure contact locking bar 60 as in the ladder-type buckle 10 described above.
Pressure contact locking bar toward the tip of male buckle 12 than 62
A rear end 51 of the support bar 50 is provided above 60.

In the ladder-type buckle 10 or the two-piece type buckle 10 in which the length of the belt 80 can be easily adjusted, the outer side of the belt 80 that is double overlapped inward and outward at the position of the pressure contact locking bar 60. The portion of the belt 80 on the base end portion 82 side and the pressure contact locking bar 60 that overlaps with each other are sandwiched between the portions of the belt 80 on the free end 81 side that directly contact the pressure contact locking bar 60. 60 underside 61 or its tip 62
Is strongly pressed.

The pressing force is related to the bending angle of the belt 80 that is bent at the position of the tip 62 of the press contact locking bar 60. That is, as shown in FIG. 9, of the belt 80 that doubles inward and outward at the position of the press contact locking bar 60, the bending angle α of the portion of the belt 80 on the proximal end portion 82 side that overlaps the outer side,
The larger the bending angle β of the portion of the belt 80 on the free end 81 side in contact with the press contact locking bar 60, the larger the pressing force can be.

Therefore, it has been attempted to increase both bending angles α and β of the belt 80, and as shown in FIG. 9, the tip 62 of the press contact locking bar 60 and the rear end 51 of the support bar 50 are formed. Some limit the horizontal distance L to the thickness of the belt 80 or less (Japanese Patent Publication No. Sho)
63-58561).

[0011]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the conventional buckle 10 in which the horizontal distance L between the front end 62 of the 60 and the rear end 51 of the support bar 50 is limited to the thickness of the belt 80 or less, the buckle is designed in consideration of the thickness of the belt 80 to be used in advance when manufacturing the buckle. , Must be manufactured. For this reason,
The conventional buckle 10 thus manufactured has a problem that the usable thickness of the belt 80 is limited.

That is, as the belt 80 becomes thinner,
The distance from the lower surface 61 of the press contact locking bar 60 to each center line of the belt 80 which is doubly overlapped thereunder becomes short. Therefore, the values of both bending angles α and β of the belt 80 are reduced, and the pressing force for pressing the lower surface 61 of the press contact locking bar 60 or the tip 62 thereof is also reduced.
Belt 80 becomes slippery.

When the buckle 10 made of synthetic resin is formed by injection molding, in order to pull out the product from the mold, the tip 62 of the pressure contact locking bar 60 and the rear end 51 of the support bar 50 are horizontally aligned. Clearance is required. Therefore, in the conventional buckle injection molding method and mold, the pressure contact locking bar 60
Since a clearance is required between the front end 62 of the rod and the rear end 51 of the support bar 50, the horizontal distance L between the pressure contact locking bar 60 and the support bar 50 cannot be zero. Had a problem in the mold splitting.

On the other hand, in order to increase both bending angles α and β of the belt 80 which is double overlapped at the position of the pressure contact locking bar 60, the vertical distance between the support bar 50 and the pressure contact locking bar 60 is set. You can increase it. However, if the vertical distance between the support bar 50 and the press-contact locking bar 60 is increased, the thickness of the buckle 10 in the up-down direction becomes thicker, which causes a problem in that the appearance and the like of the buckle 10 are deteriorated.

For the same purpose, the tip of the support bar 50 is
The length from 62 to the rear end 51 may be shortened. But,
The length from the front end 62 to the rear end 51 of the support bar 50 is calculated and determined from the viewpoint of strength, and if the length is shortened more than necessary, the strength will decrease and it cannot be adopted. There was a problem. Therefore, the invention according to claim 1 has been made in view of the problems of the above-described conventional technique, and the purpose thereof is to reliably lock the belt regardless of the thickness of the belt. An object of the present invention is to provide a buckle that can more surely prevent loosening.

The invention according to claim 2 is to provide an injection molding method capable of facilitating mass production of the buckle according to claim 1. The invention according to claim 3 is
An object of the present invention is to provide a structure of a mold capable of facilitating mass production of the buckle according to claim 1.

[0017]

The present invention is to achieve the above-mentioned object, and the contents thereof will be described below with reference to the embodiments shown in the drawings. The buckle according to claim 1, wherein the position of the tip end (61) of the pressure contact locking bar (60) is changed to the support bar.
The belt (50) is arranged in the direction of the tips (21) of the side wall portions (20) rather than the position of the rear end (51), and the belt ( It is characterized by a structure in which a part of the support bar (50) is vertically overlapped with a part of the tip (61) of the press contact locking bar (60) by forming a gap through which the (80) passes.

In the injection molding method of the buckle according to claim 2, the mold (90) is clamped according to both inclined surfaces (53, 63) provided on the support bar (50) and the pressure contact locking bar (60). And, the moving direction of the movable mold (92) in the mold opening is inclined with respect to the parting line (P) around the cavity (C) of the mold (90), and the product is removed from the mold (90). The protruding direction of the product at the time of taking out is also inclined with respect to the parting line (P) around the cavity (C).

A mold for molding a buckle according to claim 3 is a parting line at least around a cavity (C) of a mold (90) forming a cavity (C) conforming to the shape of the buckle (10). (P) is characterized by having a structure inclined with respect to the moving direction of the movable mold (92).

[0020]

[Operation] According to the buckle of claim 1, the position of the tip (62) of the press contact locking bar (60) is below the support bar (50) and the rear end (51) of the support bar (50). Side walls (20) than the position
Since it is placed in the direction of the tip (21) of,
From the tip (62) of the crimp lock bar (60) to the tip (5) of the support bar (50).
The angle of elevation of the tangent to 2) can be increased. In addition, the pressure-contact locking bar in the belt (80) that contacts the pressure-contact locking bar (60) from the rear end (51) of the support bar (50) to reach the free end (81).
The bend at the position of the tip (62) of the (60) can always be an acute angle.

According to the buckle injection molding method of the second aspect, the die-cutting of a product having a shape in which a part of the support bar (50) and a part of the pressure contact locking bar (60) overlap in the vertical direction is performed. You can easily. According to the mold for molding the buckle according to claim 3, the direction of the parting line (P) and the moving direction of the movable mold (92) can be easily obtained without dividing the mold (90) into a large number. It is possible to set the protruding direction of the product or the product to a different direction.

[0022]

1 to 4 show a first embodiment of the present invention, which shows a ladder-shaped buckle, FIG. 1 is a longitudinal sectional view showing a usage state, FIG. 2 is a plan view, 3 is a rear view and FIG. 4 is a vertical sectional view. In the figure, 10 indicates a ladder-shaped buckle, and this buckle 10 is located at the tip 21 of both side wall parts 20 so as to connect a pair of left and right side wall parts 20, 20 as shown in FIGS. It has a presser bar 30. Then, in parallel with the presser bar 30, the fixed bar 40 and the support bar 5
0, the pressure contact locking bar 60 is arranged between the left and right side wall portions 20, and both ends of the fixed bar 40, the support bar 50 and the pressure contact locking bar 60 are connected to the both side wall portions 20, respectively. Further, the buckle 10 is integrally molded of synthetic resin.

As shown in FIG. 4, the buckle 10 is provided with a fixed bar 40 rearward and upward of a holding bar 30 provided at the tips 21 of both side wall portions 20, and a side wall behind the fixed bar 40. Support bar 50 at the upper limit position according to the height of part 20
And a pressure contact locking bar 60 at the rear end 22 of the side wall portion 20. The surface of the support bar 50 facing the pressure contact locking bar 60 is an inclined surface.
In addition to 53, the pressure contact locking bar 60 also has an inclined surface 63 on the surface facing the support bar 50. Further, the position of the tip 62 on the lower surface 61 of the press contact locking bar 60 is arranged closer to the tip 21 of the side wall portions 20 than the position of the rear end 51 of the support bar 50. Further, there is a gap between the pressure contact locking bar 60 and the support bar 50, and a part of the pressure contact locking bar 60 is provided so as to overlap below the support bar 50.

Further, from the upper rear end of the press contact locking bar 60, there is a tongue-shaped projecting portion 64 projecting further rearward.
The upper surface of the support bar 50 and the lower surface of the pressure contact locking bar 60.
As shown in FIG. 3, 61 is provided with grooves. As described above, in the buckle 10 according to the present embodiment, as shown in FIGS. 2 to 4, the support bar 50 is retracted to a position where the position of the rear end 51 of the buckle 10 overlaps with the position of the tip 62 of the press contact locking bar 60. Let
The support bar 50 is arranged above the pressure contact locking bar 60 so that a gap is provided between the support bar 50 and the pressure contact locking bar 60.

On the other hand, the belt 80 has its free end 81 shown in FIG.
As shown in FIG. 4, the pressure contact locking bar 60 is passed between the fixed bar 40 and the support bar 50 from below, and folded back at the position of the support bar 50. Then, the free end 81 of the belt 80 is further passed between the support bar 50 and the pressure contact locking bar 60 and between the lower surface 61 of the pressure contact locking bar 60 and a portion of the belt 80 on the base end portion 82 side. At this time, since the tip 62 of the pressure contact locking bar 60 is located directly below the support bar 50, the belt 80 is positioned at the tip 62 of the pressure contact locking bar 60.
Is greatly bent. In particular, the portion on the free end 81 side of the belt 80 that directly contacts the press contact locking bar 60 is greatly bent so that it can always be bent at an acute angle.

Therefore, after pulling the free end 81 of the belt 80 and tightening the belt 80, as shown in FIG. 1, the belt 80 is folded back at the position of the tip 62 of the pressure contact locking bar 60 and overlaps the inside and outside double. The belts 80 are strongly pressed against each other, and a large frictional force is generated. Further, the tip end 62 of the pressure contact locking bar 60 directly and sharply digs into a portion of the belt 80, which is in direct contact, with the free end 81 side, so that the belt 80 can be reliably maintained in the tightened state.

When the belt 80 is loosened, the protrusion 64
By pushing up from the lower surface, the bending angle of the belt 80 generated at the position of the tip 62 of the pressure contact locking bar 60 is reduced,
The belt 80 can be easily loosened by releasing the contact pressure between the belts 80. FIG. 5 shows a mold for molding a ladder-shaped buckle having the above-mentioned configuration.

In injection molding of the buckle 10, as shown in FIG. 5, the moving direction of the movable mold 92 and the product take-out direction when performing mold clamping and mold opening by the mold 90 are controlled by the mold 90. The direction is oblique with respect to the ingline P. As described above, in the method in which the moving direction of the movable mold 92 and the taking-out direction of the product are set in the oblique direction with respect to the parting line P, the buckle 10 in which the support bar 50 is arranged directly above the press contact locking bar 60 is used. At the time of molding, the member forming the gap between the support bar 50 and the pressure contact locking bar 60 can be easily removed from the molded product, and the folding angle of the folded belt 80 can be increased to increase the belt 80. It is possible to easily mass-produce the buckle 10 capable of reliably locking the.

In order to carry out the above-mentioned molding method, as shown in FIG. 5, the mold 90 in which the parting line P around the cavity C is inclined with respect to the moving direction of the movable mold 92.
By using, the moving direction of the movable mold 92 can be easily inclined with respect to the parting line P.
As shown in FIG. 5, the die 90 has an irregular parting line P between the fixed die 91 and the movable die 92, and at least the parting line P around the cavity C is inclined. For this purpose, a fixed mold 91 and a movable mold 92 having a parting line P inclined with respect to the side wall of the mold 90 are used. And fixed mold 91 and movable mold
In the inclined part in the parting line P with 92,
A required recess is formed to form a cavity C that matches the shape of the product.

The mold 90 in which the parting line P around the cavity C is inclined in this manner does not use a core or an intermediate mold, but has a movable mold 92 and a fixed mold 91 only. The moving direction of 92 and the projecting direction of the product by the push pin can be made oblique with respect to the parting line P. FIG. 6 shows a second embodiment of the present invention, and is an explanatory view showing a ladder-shaped buckle and a die for molding the same.

As another embodiment of the ladder-type buckle 10, as shown in FIG. 6, both side walls are formed without forming a curved surface or an inclined surface on the lower surface 61 of the support bar 50 and the upper surface of the pressure contact locking bar 60. As a combination of planes parallel or perpendicular to the axis in the direction from the front end 21 to the rear end 22 of the portion 20, the support bar
The lower surface 61 of the 50 and the upper surface of the press contact locking bar 60 are formed. As shown in FIG. 6, the buckle 10 according to this embodiment has a fixed mold 91.
The injection molding apparatus is provided with a slider 93 that moves parallel to the parting line P of the fixed mold 91 between the movable mold 92 and the movable mold 92. Then, the slider 93 is projected into the cavity C formed by the fixed mold 91 and the movable mold 92 to perform mold clamping, whereby the tip 62 of the press contact locking bar 60 is obtained.
It is possible to easily perform the molding and mass production of the buckle 10 which is disposed directly below the support bar 50 and in which a gap serving as a passage for the belt 80 is provided between the pressure contact locking bar 60 and the support bar 50.

FIG. 7 shows another embodiment of the present invention, and is a plan view of a male buckle on one side of a two-piece buckle. In both the two-piece buckle 10 and the two-piece buckle 10, as shown in FIG.
By arranging the belt 80 further rearward, the belt 80 can be reliably locked when the belt 80 is pulled, and the belt 80 can be reliably prevented from being loosened carelessly.

[0033]

Since the present invention is constituted as described above, it has the following effects. Claim 1
According to the buckle described above, since the tip of the pressure contact locking bar is located directly below the support bar, the bending angle of the belt generated at the tip position of the pressure contact locking bar is increased,
It is possible to reliably prevent the belt from being inadvertently loosened and more reliably prevented from being loosened.

According to the injection molding method of the second aspect, it is possible to easily mold and manufacture a buckle arranged so that a part of the support bar and a part of the press contact locking bar are vertically overlapped. Therefore, it is possible to facilitate mass production of buckles that reliably lock the belt. According to the mold of the third aspect, it is possible to easily incline the moving direction of the mold and the protruding direction of the product with respect to the parting line only with the fixed mold and the movable mold. Therefore, an injection molding method in which the moving direction of the mold and the ejecting direction of the product are inclined with respect to the parting line is carried out by using a relatively simple injection molding device that has been used conventionally, and the folded belt is greatly bent. Thus, it is possible to easily carry out mass production of the buckle that can be securely locked.

[Brief description of drawings]

FIG. 1 shows a first embodiment of the present invention and is a vertical sectional view showing a usage state of a ladder-type buckle.

FIG. 2 is a plan view of a ladder-shaped buckle according to the first embodiment.

FIG. 3 is a rear view of the ladder-type buckle according to the first embodiment.

FIG. 4 is a vertical sectional view of a ladder-shaped buckle according to the first embodiment.

FIG. 5 is an explanatory view showing a mold for molding a ladder-shaped buckle according to the first embodiment.

FIG. 6 shows a second embodiment of the present invention and is an explanatory view showing a ladder-shaped buckle and a mold for molding the same.

FIG. 7 shows another embodiment of the present invention and is a plan view of a male buckle on one side of a two-piece buckle.

FIG. 8 is a perspective view showing a conventional ladder-type buckle.

FIG. 9 is a vertical cross-sectional view showing a conventional ladder-shaped buckle.

FIG. 10 is a plan view showing a conventional two-piece buckle.

[Explanation of symbols]

 10 Buckle 20 Side wall 21 Front end 50 Support bar 51 Rear end 53 Inclined surface 60 Pressure contact locking bar 62 Tip 63 Inclined surface 80 Belt 90 Mold 91 Fixed mold 92 Movable mold C Cavity P Parting line

Claims (3)

[Claims] 1. A support bar, both ends of which are connected to both side wall parts, and a pressure contact locking bar are provided in parallel between the left and right side wall parts, and the pressure contact locking bar is provided below the support bar. In a buckle made of synthetic resin capable of adjusting the belt length by folding the belt back with the support bar and passing the double-layered belt under the pressure contact locking bar, the tip position of the pressure contact locking bar is supported. By arranging in the direction of the tips of both side wall portions rather than the rear end position of the bar, and forming a gap for passing the belt between the support bar and the pressure contact locking bar,
A buckle made of synthetic resin, characterized in that a part of a support bar is arranged at a position vertically overlapping a tip portion of a pressure contact locking bar. 2. A support bar, both ends of which are connected to both side wall parts, and a pressure contact locking bar are provided in parallel between the left and right side wall parts, and the tip of the pressure contact locking bar is arranged at a position overlapping the support bar. Is
Further, there is a gap for passing the belt between the pressure contact locking bar and the support bar, and a portion of the lower surface of the support bar facing the pressure contact locking bar is an inclined surface and faces the support bar of the pressure contact locking bar. A method for injection molding a buckle made of synthetic resin, which also has an inclined surface in a portion thereof, wherein the movable mold is used for clamping and opening the mold according to both inclined surfaces provided on the support bar and the pressure contact locking bar. The moving direction should be inclined with respect to the parting line around the cavity of the mold, and the protruding direction of the product when the product is taken out from the mold should be similarly inclined with respect to the parting line around the cavity. A method of injection molding buckles made of synthetic resin. 3. A support bar, both ends of which are connected to both side wall parts, and a pressure contact locking bar are provided in parallel between the left and right side wall parts, and a belt is passed between the support bar and the pressure contact locking bar. A synthetic resin that has a gap, the pressure contact locking bar is located below the support bar, and the tip end position of the pressure contact locking bar is arranged in the front end direction of both side wall parts rather than the rear end position of the support bar. A mold for molding a buckle made of metal, wherein the parting line at least around the cavity of the mold for forming a cavity matching the shape of the buckle is
A mold having a structure inclined with respect to the moving direction of the movable mold.