JPH09174570A - Molding device for brush handle - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To inexpensively provide a molding die device capable of molding a dense bristle brush having a high commercial value by implanting hair by inclining a bunch of hair without causing burrs or breaking of a molding pin. provide. A knockout plate (2) movably arranged with respect to a fixed side mold plate (11) to define a cavity (1).
3, a plurality of guide holes 26 opening in the cavity defining surface are formed in a position and a direction in which three guide holes 26 are twisted with each other in a three-fold symmetrical shape, and each of the guide holes 26 has a straight and high rigidity. The molding pin 27 is inserted into the cavity 1 so that the tip of the molding pin 27 can be projected and retracted.
The base end side portion of 7 is loosely inserted into the mounting hole 25a of the elongated hole formed in the template 25, and the large-diameter flange portion 27a formed at the base end of the molding pin 27 is fixed to the template 25 by the fixing block 24. Fixed block 2 sandwiched so that it can move in parallel
4 and the template 25 are connected to the knockout plate 23 while allowing a predetermined displacement, and are driven by a drive mechanism or the like for driving the knockout plate 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding device for a brush handle used for manufacturing a toothbrush, a brush for hair, etc. The present invention relates to a molding die device for molding.

[0002]

2. Description of the Related Art Recent brushes, especially toothbrushes, have a reverse V-shaped brush on the brush-planted surface of the brush handle for the purpose of improving the effect of removing plaque and preventing the hair tips from spreading during use. Various types of so-called slanted flocking brushes have been put into practical use, in which the bristles are slanted in a letter shape and are transplanted, and in which the axes of a plurality of adjoining bunches are slanted so as to be concentrated at one point. Even the applicant of the present invention applied for this type of toothbrush by applying for a patent.
It was previously proposed in No. 332379. In this toothbrush, three bristle bundles on the flocked surface are arranged in a triangular pyramid shape, and a plurality of pairs of these bristle bundles are provided.

By the way, the above-mentioned Japanese Patent Application No. 6-33237.
In the toothbrush proposed in No. 9, it is indispensable to form the bristles in the brush handle obliquely. Therefore, in manufacturing such a toothbrush, a method of forming a brush handle having no bristles and forming bristles on the brush handle by machining (hereinafter, referred to as Prior Art 1) is also used. The slide block is provided with a molding pin for forming pores and the molding pins of different lengths are operated independently (conventional technology 2), and the shape of the molding pin is devised to deal with it (conventional technology 3). Has been done.

However, the conventional technique 1 is easy to mold the brush handle, but has a drawback that it is not suitable for mass production because productivity and yield are poor because the bristles are formed in the brush handle after molding. . Further, in the prior art 2, since the slide blocks must be stacked in each inclination direction of the molding pins, the molding pins having a shape and a length corresponding to the position of each slide block are required, and the molding pins cannot be shared. Also, there is a drawback that the mold structure becomes complicated.

Therefore, in recent years, Japanese Patent Publication No. 6-20796
Attempts have been made to manufacture a brush handle using the method of Prior Art 3 represented by Japanese Patent Publication No. 57-38253 and Japanese Utility Model Publication No. 57-38253. The former Japanese Examined Patent Publication No. 6-20796 describes a molded pin, a part of which is made flexible, to elastically bend to form a flocked hole, and the latter, Japanese Utility Model Publication No. 57-.
Japanese Patent No. 38253 discloses that an arc-shaped molding pin is inserted and removed to form a hair-implanted hole.

[0006]

However, in the former Japanese Patent Publication No. 6-20796, since the molding pin is elastically repeatedly bent, the molding pin and the guide hole are unevenly worn and the molding product has a burr. There is a problem that a gap that causes the above is likely to occur between the guide hole and the forming pin, and that the bent portion of the forming pin is likely to be broken or buckled due to stress concentration or fatigue.

Further, in the latter Japanese Utility Model Publication No. 57-38253, since an arc-shaped forming pin is used, the space required for its arrangement is large and the space between adjacent forming pins is large, so that a molded product is obtained. Also, the distance between the flocking holes of the brush handle becomes large, a dense brush cannot be achieved, the commercial value of the brush is unavoidable, and the guide hole must be formed in an arc shape. Inevitably, there is a problem that the manufacturing cost of the mold also increases. This invention has been made in view of the above problems,
An object of the present invention is to provide at low cost a molding die device capable of molding a dense bristle brush having a high commercial value without causing burrs or breaking of a molding pin.

[0008]

In order to achieve the above object, the present invention is a mold device for molding a brush handle, in which a plurality of holes for bristling hair are obliquely formed in a bristle surface, and the brush handle is fixed. A movable die is arranged with respect to the die so as to define a cavity in a mold closed state, and a plurality of guide holes that open to the cavity defining surface of the movable die are set as one set, and three guide holes are arranged in a three-fold symmetrical shape. It is formed in a position and direction that is twisted in the direction of the movable mold and is inclined with respect to the moving direction of the movable mold, and the tip side portion of the molding pin for forming the flocked hole can be slid substantially liquid-tightly in these guide holes The base end side portion of the molding pin is connected to a connecting member by allowing displacement in a direction orthogonal to the moving direction of the movable die, and the connecting member is driven in the moving direction of the movable die to Insert the tip of the molding pin into the cavity. It was configured to.

According to the present invention, the connecting member includes a template in which a pin mounting hole into which the molding pin is loosely inserted is formed, and a fixing block which is coupled to the template and defines a hooking gap. A mode in which the molding pin has a flange portion having a diameter larger than that of the pin mounting hole at the base end, and the molding pin inserts the pin mounting hole and the guide hole with the flange portion positioned in the locking gap. 2) can be configured. Further, the present invention is configured in such a manner that a molding pin having a small diameter reduced portion is provided in an intermediate portion protruding from the guide hole to the opposite side of the cavity in a state where the molding pin is recessed from the cavity into the guide hole (claim 3). can do.

The molding die apparatus of the present invention is used for injection molding of a brush handle of various brushes such as a toothbrush and a hair brush, and particularly for injection molding of a head portion having a flocked surface. A well-known basic structure such as a mold is used. The guide holes are formed as a set of three and open in the cavity-defining surface of the movable die, and the set of guide holes extend obliquely in a position and a direction in which they are twisted in a three-fold symmetrical shape. At least a portion near the opening to the cavity defining surface is formed along a generatrix of an imaginary triangular pyramid having the opening as a large diameter side.

The molding pin is made of a straight member having a corresponding rigidity. The distal end portion is inserted into the guide hole so as to be slidable in the longitudinal direction and movable in parallel, and the proximal end portion is a movable member for the connecting member. They are connected by allowing a displacement in a direction orthogonal to the moving direction. In these molding pins, the portion located in the guide hole in a state where the molding pin projects into the cavity, or the portion and the portion on the base end side of the portion are reduced diameter portions having a smaller diameter than the tip portion. Is desirable. The connecting member is driven in a predetermined time schedule for moving to the movable mold in the moving direction of the movable mold by using the driving force of the movable drive mechanism, the ejector mechanism, or a dedicated drive mechanism, etc. Before the resin is injected, the tip side of the molding pin is projected into the cavity, and the tip of the molding pin is driven at the same time as the mold opening that drives the movable mold in the opening direction after molding, or before or after mold release by the ejector pin. Immerse the side part in the movable mold.

[0012]

In the present invention, each molding pin is integrally driven through the connecting member with the fixed mold and the movable mold being closed to define the cavity, and the tip end is projected into the cavity from the guide hole. Then, the molten resin is injected in this state. Here, since the molding pin is liquid-tightly fitted in the guide hole, there is no gap that may cause burrs or the like. Then, when the molten resin is cured (when the fluidity is lost), in other words, before or simultaneously with the mold release by the ejector pin, each molding pin is driven in the opposite direction by the connecting member to move its tip end portion. Immerse in the movable mold. Here, when the forming pin is retracted, the forming pin moves in the extending direction of the guide hole, but since the displacement in the orthogonal direction is allowed between the forming pin and the connecting member, the forming pin is guided by the guide pin. Smoothly slides in the hole. Therefore, uneven wear or bending does not occur, and the guide hole can be formed in the movable die by a drill or the like, so that the die can be manufactured at low cost.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 8 show a molding apparatus for a brush handle according to an embodiment of the present invention, FIG. 1 is a sectional view of the molding apparatus, and FIG. 2 is a drawing of the same molding apparatus.
2 is a sectional view of the mold apparatus in a state following FIG. 2, FIG. 4 is a partially enlarged view of FIG. 1, and FIG. 5 is a front view of the mold apparatus seen through. 6 is an enlarged front view showing another main part of the mold apparatus, FIG. 7 is a perspective view of a head portion of a brush handle of a toothbrush, and FIGS. 8a and 8b are plan views of the head portion.

First, the toothbrush to be molded will be described with reference to FIGS. 7 and 8a. In the figure, reference numeral 1 denotes a head portion of a brush handle of a toothbrush, a plurality of hair-implanted holes are formed on a hair-implanted surface of the head portion 1 of the brush handle, and hair tufts 2 are respectively implanted in these hair-implanted holes.
These three tufts 2 are set in three tufts adjacent to each other in the tufting holes of the tufting surface, and the three tufts 2 forming the tuft extend obliquely from the tufting surface so as to form a substantially triangular pyramid shape. The bristles of the head part 1 of the brush handle are formed as one set corresponding to the bunch of hairs 3, and the three bristles of the set are inclined so as to form a generatrix of a triangular truncated pyramid. This brush handle is molded by injection molding using a molding die device described later, and a flock hole is formed by a molding pin described later during this molding.

Next, the molding die device will be described with reference to FIG.
In 2 and 3, 11 is a fixed-side template fixed to a fixed-side mounting plate (not shown), and 20 is a movable-side mounting plate attached to the base of the apparatus so that it can be driven to move up and down.
A knockout plate pedestal 22 is attached to the movable side attachment plate 20 via a spacer block 21, and a knockout plate (movable type) 23 and a fixed block 24 and a template 25 are attached to the knockout plate pedestal 22.

The fixed-side mold plate 11 has a concave portion on the lower surface in the drawing which faces the knockout plate 23, and this concave portion together with the concave portion of the knockout plate 23 when the mold is closed (for convenience, a handle cavity). The same number as 1) is defined. Although not shown, a known sprue bush or the like is provided on the fixed-side template 11 so as to face the cavity 10, and the cavity 10 is connected to the supply source of the molten resin via the sprue bush or the like.

The knockout plate 23 has a substantially gate-shaped cross section, and has a concave portion (reference numeral is omitted) which defines the cavity 1 on the upper surface in the figure which faces the fixed side template 11. A plurality of guide holes 26 that open to the bottom surface of the recess are formed in the knockout plate 23 so as to extend vertically in the drawing, and molding pins 27 are slid into the guide holes 26 at the same inclination angle as the guide holes 26. It is inserted freely. These three guide holes 26 form a triangular pyramid generatrix as a set (see FIGS. 5, 7, and 8a), and the guide holes 26 of each set extend in positions and directions in which they are twisted in a three-fold symmetrical shape. To do. Although detailed explanation is omitted, knockout plate 2
Reference numeral 3 is connected to a known mold opening / closing mechanism and is driven up and down in the drawing.

Each of the molding pins 27 is formed by straightly molding a high-rigidity material such as tool steel into the same length, and integrally has a flange portion 27a having an enlarged diameter at the base end. As described above, the molding pin 27 has a distal end portion which is inserted into and retracted from the bottom surface of the concave portion in the guide hole 26, and a proximal end portion which is loosely inserted into the mounting hole 25a formed in the template 25.
7a hooks on the periphery of the mounting hole 25a on the lower surface of the template 25.

The template 25 has a substantially gate-shaped cross section, and the lower portion in the figure is fixed to the fixed block 24 to form a gap 29 between the fixed block 24 and the fixed block 24. In the template 25, a plurality of mounting holes 25a described above are formed in the same position as the above-described guide holes 26 in a three-fold set in a position and a direction in which the three mounting holes 25a penetrate vertically in the drawing and are twisted with each other. The forming pin 27 is inserted into the mounting holes 25a by hooking the flange portion 27a on the lower surface in the space 29. As shown in FIGS. 4 and 6, these mounting holes 26 have an elliptical cross-section whose longitudinal direction coincides with the inclination direction of the molding pin 27, and the major axis and the minor axis of which have the above-described collar portion. It is smaller than the diameter dimension of 27a.

The fixed block 24 is connected to the knockout plate 23 by allowing a predetermined relative displacement in the vertical direction in the drawing, and is connected to the template 25 by using the power of a mold opening / closing mechanism for driving the knockout plate 23 or an eject mechanism described later. Driven together. However, the fixed block 24 can also be driven by a single (dedicated) drive mechanism, and the drive mechanism may be a mechanism using hydraulic or pneumatic cylinders, a mechanism using a motor, etc., regardless of the actuator type. Can be adopted.

Reference numeral 31 is an eject pin, and the eject pin 31 has its tip on the bottom surface of the recess of the knockout plate 23, that is, the knockout plate pedestal 22, the fixed block 24, the template 25 and the knockout plate 23 so that the eject pin 31 can project and retract into the cavity 1. Penetrates through. As is well known, this eject pin 31
Has a proximal end connected to the plate 32, and the plate 32
It is driven up and down by an eject mechanism connected to.

In this embodiment, the brush handle 1 is molded as described below. First, as shown in FIG. 1, the knockout plate 23 is moved upward and the mold is closed to define the cavity 1. Here, at the same time when the knockout plate 23 is moved up, or after the cavity 1 is defined, the fixed block 24 and the template 25 are
Are integrally moved upward so that the tip portion of the molding pin 27 projects into the cavity 1. Then, in this state, the molten resin is injected into the cavity 1.

After the molten resin in the cavity 1 is hardened and the brush handle 1 is molded, the knockout plate 23 is lowered to open the mold as shown in FIG. The fixed block 24 and the template 25 move downward together with the knockout plate 23 in the initial downward movement of the knockout plate 23. When the knockout plate 23 moves down by a predetermined distance, the knockout plate 2
3 engages with a stopper or the like, and the fixed block 24 fixed to the knockout plate pedestal 22 and the template 25 move downward with respect to the knockout plate 23, and are separated from each other by a constant distance (a length equivalent to S in FIG. 10). At this time, the tip of the molding pin 27 is detached from the molded brush handle 1, and a brush hole is formed in the brush handle 1, so that the entire mold member with respect to the fixed-side mold plate 11 is maintained while maintaining the separation distance S. Move further down including the brush handle 1.

Here, when the fixed block 24 and the template 25 move downward with respect to the knockout plate 23,
The forming pin 27 slides in the guide hole 26 and moves in the extending direction of the guide hole 26, and the base end side is also displaced in the left and right directions in the drawing, but the forming pin 27 is a long hole of the template 25 on the base end side. Movement in the left-right direction in the drawing relative to the template 25, that is, parallel movement is allowed by being loosely inserted in a certain mounting hole 25a. Therefore, the molding pin 27 has no trouble, that is,
The tip end part separates from the brush handle 1 without causing uneven wear or bending deformation with the knockout plate 23.

After that, as shown in FIG. 3, the eject pin 31 moves upward to push out the molded brush handle 1 to release the brush handle 1. In the molding of the brush handle 1 described above, the knockout plate 23
First, the fixed block 24 and the like are moved down integrally, but first, after the fixed block 24 and the like are moved down by a predetermined distance by another drive device, that is, the tip portion of the molding pin 27 is a brush which is a molded product. It is also possible to push out the eject pin 31 after separating from the handle 1. In this case, the knockout plate pedestal 22 can be omitted and the knockout plate 23 can be directly connected and fixed to the spacer block 21. It is also possible to use the above-mentioned molding pin 27 as an eject pin. That is, at the time of releasing the brush handle 1, it is also possible to move the fixing block 24 and the like upward to cause the tip end portion of the molding pin 27 to project onto the knockout plate 23, and to push up the brush handle 1 with the projecting molding pin 27. Is.

9 to 14 show a molding apparatus for a brush handle according to another embodiment of the present invention.
Is a cross-sectional view, FIG. 10 is a partially enlarged view thereof, FIG. 11 is an enlarged front view of a molding pin, FIG. 12 is a partially enlarged perspective plan view, and FIG. 13 is a plan view of the template seen in the same arrow as FIG. 14A and 14B are cross-sectional views and plan perspective views described in connection with the above-described embodiment. The same parts as those in the above-described embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, as shown in FIG.
A reduced diameter portion 27c having a small diameter is formed in an intermediate portion of the molding pin 27, and both side portions thereof are used as large diameter portions 27d and 27e. As shown in FIG. 9, the large-diameter portion 27d on the distal end side is a portion protruding into the cavity 1 and a portion slidably inserted into the guide hole 26, and the large-diameter portion 27e on the proximal end side is inside the mounting hole 25a. Formed as a portion to be loosely inserted into the reduced diameter portion 27
c is located in the space 29 with its tip being recessed from the cavity 1 into the guide hole 26.

Then, as shown in FIG. 10, the molding pin 27 has a length of a portion protruding into the cavity 1 of S,
The length of the portion that is inserted into the guide hole 26 in the state of being immersed in the guide hole 26 from the cavity 1 is L (equal to the length of the guide hole 26), the diameter is D, the inclination angle is θ, and the guide hole is Letting P be the opening interval of the cavity 26 to the cavity 1 and T be the wall thickness of the knockout plate 23, the wall thickness T and the length L of the guide hole 26 are determined so as to satisfy the following equations 1 and 2, respectively. .

[0029]

(Equation 1)

(Equation 2) However, it is desirable to determine so as to satisfy T ≧ 4D, L ≧ 4D, and L−S ≧ 2D.

Also in this embodiment, the molding pin 27
As shown in FIG. 12, the large diameter portion 27d has a guide hole 26
The large diameter portion 27e and the mounting hole 25e (see FIG. 13).
(Refer to FIG. 3) and are arranged in a position and a direction in which they are twisted in a three-fold symmetrical shape. Since the base end portion of the molding pin 27 is allowed to move in the left-right direction in the drawing, the molding pin 27
Can be moved up and down without hindrance, the mold device can be achieved at low cost without the need for complicated processing on the mold, and high reliability and excellent durability can be achieved without uneven wear or bending. can get.

In particular, in this embodiment, since the diameter-reduced portion 27a is formed on the molding pin 27, the directional centers of the three molding pins 27, in other words, the three hair bundles 2 that are implanted in the hair-implanting holes.
The directional centers of can be more closely matched, and an excellent toothbrush can be obtained. That is, to explain in comparison with the above-described embodiment, as shown in FIG. 14A, in the above-described embodiment, a portion where the molding pins 27 intersect (shown by diagonal lines) thickly interferes with each other, so that the interval between them is small. It is difficult to do, and it is a molded product.
It is difficult to configure the so that the pointing direction is concentrated at one point (see FIG. 8a). On the other hand, in this embodiment, since the molding pins 27 can be arranged close to each other as shown in FIG. 14b, it is possible to mold the brush handle 1 in which the directions of the tufts 2 are aligned as shown in FIG. 8b. , It is possible to manufacture toothbrushes with high commercial value.

In each of the embodiments described above,
The three guide holes 26, that is, the molding pins 27 are arranged as a set in a substantially triangular pyramid shape.
As a set, it has a substantially quadrangular pyramid shape, or five guide holes 26.
It is also possible to arrange them in a substantially pentagonal pyramid shape.

[0033]

As described above, according to the molding apparatus for a brush handle according to the present invention, the movable die is provided with three guide holes which are open to the cavity defining surface.
As a set, they are formed in a three-fold symmetric shape in a mutually twisted position and in a direction inclined with respect to the moving direction of the movable mold, and the tip side parts of the molding pins for forming the flocked holes are slidably inserted into these guide holes, respectively. A base end side portion of the forming pin is connected to a connecting member by allowing displacement in a direction orthogonal to the moving direction of the movable die, and the connecting member is driven in the moving direction of the movable die to move the forming pin. Since the tip portion is sunk into and out of the cavity, a mold such as a movable mold can be manufactured at low cost without complicated processing, and the molding pin does not have bending that causes fatigue or stress concentration. In addition, the bristles can be integrally formed in the brush handle without causing uneven wear in the movable guide holes or the like.

Further, in the molding die apparatus according to the second aspect of the present invention, a large-diameter flange portion is formed on the molding pin, and the molding pin is inserted into the template so that the flange portion is movable between the template and the fixed block. Since the clamping is performed while allowing the displacement in the direction orthogonal to the moving direction, the molding pin can be easily attached with a simple structure.

Further, the molding die apparatus according to claim 3 is
Since the middle part of the molding pin, that is, the intersecting part, has a reduced diameter part with a small diameter, it is possible to more closely align the directional centers of the flocked holes formed in the brush handle, and a toothbrush with excellent bunch arrangement is manufactured. it can.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a brush handle molding die apparatus according to an embodiment of the present invention. .

FIG. 2 is a schematic cross-sectional view of the mold apparatus in a state following FIG.

FIG. 3 is a schematic cross-sectional view of the mold apparatus in a state following FIG.

FIG. 4 is an enlarged cross-sectional view of a part of the mold device.

FIG. 5 is an enlarged perspective view of a part of the mold apparatus.

FIG. 6 is a cross-sectional view of a part of the mold apparatus taken along the same arrow as in FIG.

FIG. 7 is an enlarged perspective view of a part of a brush handle of a toothbrush molded by the mold device.

FIG. 8 is a plan view of the brush handle in which a shows one aspect and b shows another aspect.

FIG. 9 is a schematic cross-sectional view of a mold device according to another embodiment of the present invention.

FIG. 10 is an enlarged cross-sectional view of a part of the mold apparatus.

FIG. 11 is a front view of a molding pin that is a main component of the mold device.

FIG. 12 is a plan view showing a part of the mold apparatus in an enlarged perspective manner.

FIG. 13 is a cross-sectional view of a part of the mold apparatus taken along the same arrow as in FIG.

FIG. 14 shows a comparison of essential parts of a mold apparatus according to two embodiments of the present invention, where a is the embodiment of FIG. 1 and b is the embodiment.
Shows the embodiment of FIG.

[Explanation of symbols]

 1 Brush Handle 2 Hair Bundle (Flocking Hole) 11 Fixed Side Template 23 Knockout Plate (Movable Side Template) 24 Fixed Block 25 Template 26 Guide Hole 27 Molding Pin 27a Collar 27c Reduced Diameter 27d Large Diameter 27e Large Diameter 29 Space 31 Eject pin

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Ryuichi Isaka 1-3-7, Sumida-ku, Tokyo Lion Co., Ltd. (72) Inventor Masuhiro Yogo 1-3-7, Sumida-ku, Tokyo Inside Lion Corporation (72) Inventor Yuji Tanaka 1-3-7 Main Office, Sumida-ku, Tokyo Inside Lion Corporation

Claims (3)

[Claims] 1. A mold device for molding a brush handle, in which a plurality of holes for bristling hair are obliquely formed on a flocking surface,
A movable die is arranged so as to define a cavity in a mold closed state with respect to a fixed die, and a plurality of guide holes opening to the cavity defining surface of the movable die are set as a set of three to form a three-fold symmetric type. The guide pins are formed so as to be inclined with respect to the position and direction in which they are twisted to each other and inclined with respect to the moving direction of the movable die, and slidably inserted into the guide holes, respectively, at the tips of the molding pins for forming straight flocked holes. Then, the base end side portion of the forming pin is connected to the connecting member by allowing displacement in the direction orthogonal to the moving direction of the movable die, and the connecting member is driven in the moving direction of the movable die to form the forming pin. A mold device for a brush handle, wherein a tip portion of the brush is projected and retracted into the cavity. 2. The molding member, wherein the connecting member includes a template having a pin mounting hole into which the molding pin is loosely inserted, and a fixing block which is coupled to the template to define a hooking gap. 2. The brush handle according to claim 1, wherein the base end is provided with a collar portion having a diameter larger than that of the pin mounting hole, and the collar portion is positioned in the locking gap to insert the pin mounting hole and the guide hole. Molding die equipment. 3. The molding die device for a brush handle according to claim 1, wherein the molding pin is provided with a reduced diameter portion at an intersecting portion.