JP2001150499A - Mold for injection molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold for injection molding capable of easily releasing a molded product from the mold by a simple additional structure and improving the appearance of the product. SOLUTION: A fixed side ejector pin 4 spring-urged and release-inhibited projectably from the split surface of the mold and a movable side ejector pin 5 are respectively attached to a fixed mold 2 and a movable mold 3. These pins 4, 5 are disposed oppositely at the edge of the product to be molded. Contact surfaces 4D, 5D contacted with one another in a state in which the mold is closed and push surfaces 4E, 5E capable of pushing the product in association with opening of the mold are respectively formed at the end faces of the pins 4, 5. In this case, the surfaces 4E, 5E are formed as parts of a cavity surface partly corresponding to the edge of the product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding die, and more particularly, to an injection molding die that can easily remove an injection-molded product.

[0002]

2. Description of the Related Art An injection molding die for injection molding a product in a cavity between a fixed mold (cavity mold) and a movable mold (core mold) is configured so that the molded product can be easily removed from the mold. Molds are generally known. As one example, FIG. 6 of Japanese Patent Application Laid-Open No. 5-285999 discloses an injection mold having a large number of extrusion pins for extruding a molded product in conjunction with opening of the mold.

Here, in general, a product formed by an injection molding die adheres to a movable mold as the mold is opened and comes off a fixed mold, so that the extrusion pin pushes the product out of a movable core mold. It is configured as follows. That is,
The extrusion pins penetrate the core mold and are configured to be relatively movable in the opening and closing movement direction, and the base end of each extrusion pin is supported by an extrusion plate arranged on the back side of the core mold. . The tip surface of each extrusion pin faces the cavity surface of the core mold when the mold is closed, and forms a part of the cavity surface. It is configured to extrude the product relatively protruding from the cavity surface.

[0004]

By the way, in the conventional injection mold described in FIG. 6 of the above publication, it is necessary to form a large number of through holes corresponding to a large number of extrusion pins in a core mold with high precision. However, there is a problem that the manufacturing cost of the core mold increases. In addition, since the tip surfaces of a large number of extrusion pins constitute a part of the cavity surface of the core mold, the molded product has a large number of molding marks corresponding to the shape of the tip surface of each extrusion pin over a wide range. There is a problem that the appearance of the product is significantly impaired.

Accordingly, an object of the present invention is to provide an injection mold capable of easily removing a molded product with a simple additional structure and improving the appearance of the product. And

[0006]

Means for Solving the Problems As means for solving the above problems, an injection mold according to the first invention is a mold for injection molding a product in a cavity between a fixed mold and a movable mold. The fixed mold is provided with a fixed-side pushing member that is spring-biased so as to protrude from the mold division surface and is prevented from falling out, and the movable mold is capable of projecting from the mold division surface. A movable-side extruding member which is spring-biased and is prevented from coming off is provided, and both the fixed-side extruding member and the movable-side extruding member are formed with contact surfaces which come into contact with each other when the mold is closed. In addition, at least the movable-side extruding member is formed with an extruded surface capable of extruding a product as the mold is opened.

In the injection mold according to the first aspect of the present invention, as the product is opened after the injection molding of the product, the fixed-side extruding member projects from the mold dividing surface of the fixed mold by a spring urging force.
The movable side pushing member protrudes from the mold dividing surface of the movable mold by a spring biasing force. Then, at least the movable-side extruding member removes the product from the mold by extruding the product attached to the movable mold on the extruded surface.

An injection mold according to a second aspect of the present invention is the injection mold of the first aspect, wherein the biasing force of the fixed-side pushing member is set to be stronger than the spring biasing force of the movable-side pushing member. It is characterized by having.

In the injection mold according to the second aspect of the present invention, as the product is opened after the injection molding of the product, first, the fixed-side extruding member having a stronger spring biasing force than the movable-side extruding member is divided into a fixed mold. Then, the movable extrusion member projects from the mold dividing surface of the movable mold. Then, at least the movable-side extruding member surely removes the product from the mold by extruding the product adhered to the movable mold on the extruded surface.

An injection mold according to a third aspect of the present invention is the injection mold of the first or second aspect, wherein a fixed-side extrusion pin as the fixed-side extrusion member and a movable-side extrusion member as the movable-side extrusion member. A movable-side extrusion pin, wherein the fixed-side extrusion pin and the movable-side extrusion pin are arranged such that a front end surface is opposed to an edge of a product to be injection-molded, and the front end surface has the contact surface. And each of the extrusion surfaces is formed as a part of a cavity surface corresponding to a part of an edge of a product.

In the injection molding die according to a third aspect of the present invention, as the product is opened after the injection molding of the product, the fixed-side pushing pin protrudes from the fixed mold dividing surface by a biasing force of a spring.
The movable-side push pin protrudes from the movable mold dividing surface by the biasing force of the spring. Then, the fixed-side push pin and the movable-side push pin remove the product from the fixed mold and the movable mold by extruding the edge of the product with the extrusion surface formed on the tip surface.

An injection mold according to a fourth aspect of the present invention is the injection mold of the first or second aspect, wherein a fixed-side extrusion pin as the fixed-side extrusion member and a movable-side extrusion member as the movable-side extrusion member. A movable-side push-out pin, the fixed-side push-out pin and the movable-side push-out pin are arranged opposite to each other near an edge of a product to be injection-molded, and the contact surface is formed at a tip end surface thereof, Further, the extruded surface is formed as a part of a cavity surface corresponding to a waste portion which is continuous with an edge of the product.

[0013] In the injection mold according to the fourth aspect of the present invention, as the product is opened after the injection molding of the product, the fixed-side pushing pin protrudes from the fixed mold dividing surface by a spring urging force.
The movable-side push pin protrudes from the movable mold dividing surface by the biasing force of the spring. Then, the fixed-side push pin and the movable-side push pin remove the product from the fixed mold and the movable mold by extruding waste meat continuous to the edge of the product on the extruded surface formed at the tip surface.

An injection molding die according to a fifth aspect of the present invention is the injection molding die of the first or second aspect, wherein the fixed-side extrusion pin as the fixed-side extrusion member and the movable-side extrusion member as the movable-side extrusion member. A movable-side extrusion pin, wherein the fixed-side extrusion pin is disposed near an edge of the product to be injection-molded, and the movable-side extrusion pin is disposed with a front end face facing an edge of the product to be injection-molded. The contact surface is formed on the distal end surface of the fixed-side extrusion pin, the contact surface is formed on the distal end surface of the movable-side extrusion pin, and the extrusion surface is formed of a product. It is characterized in that it is formed as a part of the cavity surface corresponding to a part of the edge end surface.

In the injection mold according to the fifth aspect of the present invention, as the product is opened after the injection molding of the product, the fixed-side extrusion pin protrudes from the fixed mold dividing surface by a spring urging force.
The movable-side push pin protrudes from the movable mold dividing surface by the biasing force of the spring. The movable extrusion pin removes the product from the movable die by extruding the edge end surface of the product adhered to the movable die with the extrusion surface formed on the tip end surface.

An injection mold according to a sixth aspect of the present invention is the injection mold of the first or second aspect, wherein the fixed-side extrusion pin as the fixed-side extrusion member and the movable-side extrusion member as the movable-side extrusion member. An extrusion insert is provided, and the fixed-side extrusion pin is disposed near an edge of a product to be injection-molded, and the abutment surface is formed at a tip end surface thereof, and is provided on a surface of the extrusion insert. Is characterized in that the contact surface is formed and the extruded surface is formed as a part of a cavity surface corresponding to a predetermined portion of the product.

In the injection molding die according to the sixth aspect of the present invention, as the product is opened after the injection molding of the product, the pushing pin projects from the fixed mold dividing surface by the biasing force of the spring, and the pushing insert comes with the spring. It protrudes from the mold separation surface of the movable mold due to the force. Then, the extrusion insert removes the product from the movable mold by extruding a predetermined portion of the back surface of the product adhered to the movable mold with the extrusion surface formed on the surface.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an injection mold according to the present invention will be described below with reference to the drawings. In the drawings to be referred to, FIG. 1 is a cross-sectional view of an injection molding die according to a first embodiment, and FIG. 2 is a front view showing a mold dividing surface of a movable die of the injection molding die according to the first embodiment. 3 is a perspective view of a fixed-side extrusion pin and a movable-side extrusion pin which constitute main parts of the injection molding die according to the first embodiment, and FIGS. 4 to 6 are fixed sides of the injection molding die according to the first embodiment. It is a fragmentary sectional view of a metallic mold showing operation of an extrusion pin and a movable side extrusion pin.

As shown in FIGS. 1 and 2, an injection mold 1 according to a first embodiment of the present invention includes a pair of left and right cavities C, C between a fixed mold 2 and a movable mold 3. This is a mold for injection molding a pair of symmetrical products, and a sprue S is provided in the fixed mold 2. The sprue S communicates with the cavities C, C via a gate G from a runner R formed between the fixed mold 1 and the movable mold 2. And in the injection molding die 1 of the first embodiment,
A fixed-side pushing pin 4 which is spring-biased so as to be able to protrude from the mold dividing surface and is retained is attached to the fixed mold 2 as a fixed-side pushing member, and is also spring-biased so as to protrude from the mold dividing surface. The movable-side push-out pin 5 which has been prevented from coming off is attached to the movable mold 3 as a movable-side push-out member.

As shown in FIG. 3, the fixed-side push-out pin 4 has a columnar shape with a spring receiving hole 4A opened at the base end surface, and has a cutting surface parallel to the axial direction on the distal end side. A surface 4B and a step 4C orthogonal to the surface 4B are formed. As shown in FIG. 1, the fixed-side push-out pin 4 is inserted from the base end face side into a guide hole 2 </ b> A opened on the mold division surface of the fixed mold 2. Then, the fixed-side pushing pin 4
The stepped portion 4C is locked by a stopper block 6 fixed to the fixed die 2 facing the guide hole 2A, thereby forming the guide hole 2A.
A is prevented from falling off, and is urged by a coil spring 7 inserted into the spring receiving hole 4A so as to be able to protrude from the mold dividing surface of the fixed mold 2 by a predetermined amount.

On the other hand, as shown in FIG. 3, the movable push-out pin 5 has a columnar shape with a spring receiving hole 5A opened at its base end surface, and its peripheral surface on the distal end side is parallel to the axial direction. A cut surface 5B and a step 5C orthogonal to the cut surface 5B are formed. As shown in FIG. 1, the movable side push pin 5 is inserted from the base end face side into a guide hole 3 </ b> A opened on the mold division surface of the movable mold 3. The movable push-out pin 5 is prevented from falling out of the guide hole 3A by engaging the step 5C with a stopper block 8 fixed to the movable die 3 facing the guide hole 3A. The movable spring 3 is biased by a coil spring 9 inserted into the movable mold 5A so as to be able to protrude from the mold dividing surface of the movable mold 3 by a predetermined amount.

As shown in FIG. 1, the fixed-side push pin 4 and the movable-side push pin 5 are arranged such that the tip end faces the edge of a product to be injection-molded in the cavity C. As shown in FIG. 2, the arrangement locations are set at four locations on the peripheral edge of the left and right cavities C, C. As shown in FIG. 1 and FIG. 3, the distal end surfaces of the fixed-side push pin 4 and the movable-side push pin 5
Abutment surfaces 4 of the injection mold 1 that abut against each other in a closed state;
D and 5D are formed respectively, and extrusion surfaces 4E and 5E capable of extruding the product with the opening of the injection molding die 1 are respectively formed as a part of a cavity surface corresponding to a part of an edge of the product. ing.

Here, the coil spring 7 is set to have such a strength that a product formed in the cavity C can be extruded from the fixed mold 2 via the extruded surface 4E of the fixed-side extruded pin 4. Similarly, the coil spring 9 is set to have such a strength that a product formed in the cavity C can be pushed out of the movable die 3 through the pushing surface 5E of the movable pushing pin 5. The strength of the coil spring 7 is set to be relatively larger than the strength of the coil spring 9. That is, the spring urging force of the fixed-side pushing pin 4 is set to be stronger than the spring urging force of the movable-side pushing pin 5.

In the injection molding die 1 of the first embodiment, as shown in FIG. 1, a pusher pin 10 capable of extruding the molding resin of the runner R portion from the die dividing surface of the movable die 3 after opening the die. It is attached to the center of the movable mold 3.
The pusher pin 10 has a collar 10 at an intermediate portion in the longitudinal direction.
A of the movable die 3 is slidably fitted in a guide hole 3B opened in the runner R portion of the movable die 3. The proximal end side of the pusher pin 10 slidably penetrates a stopper ring 11 fitted and fixed to a large-diameter hole 3 </ b> C opened on the back surface of the movable die 3. The flange 10A of the pusher pin 10 is slidably disposed in a spring receiving hole 3D formed between the guide hole 3B of the movable die 3 and the large-diameter hole 3C. It is pressed toward the stopper ring 11 by the accommodated coil spring 12.

That is, the pusher pin 10 is provided with the runner R by the coil spring 12 pressing the collar 10A.
It is urged in the retraction direction from the part and is prevented from falling off by a stopper ring 11 that locks the collar 10A. And
The pusher pin 10 presses the base end protruding from the stopper ring 11 against the coil spring 12 with an appropriate jig, so that the front end protrudes from the mold dividing surface of the movable mold 3 to form the runner R portion. It is configured so that the molding resin can be extruded.

According to the injection molding die 1 of the first embodiment configured as described above, in the mold closed state shown in FIG. 1, the sprue S of the fixed die 2 passes through the runner R and the respective gates G and left and right. The molding resin material in a molten state is injected into the cavities C, C to form a product in the cavities C, C. At this time, the extruding surface 4 formed on the distal end surfaces of the fixed-side extruding pin 4 and the movable-side extruding pin 5
E and 5E constitute a part of the cavity surface,
The extruded surfaces 4E and 5E form a part of the edge of the product.

When the movable mold 3 starts moving in a direction away from the fixed mold 2 with opening of the product after injection molding, first, as shown in FIG. The fixed-side pushing pin 4 having a stronger spring biasing force than the pin 5 projects from the mold dividing surface of the fixed mold 2. These fixed-side push-out pins 4 remove the product from the fixed mold 2 by extruding the edge of the product at the push-out surface 4E of the tip end surface. At this time, the fixed-side pushing pin 4 presses the contact surface 5D of the movable-side pushing pin 5 with the contact surface 4D, and stops the protrusion of the movable-side pushing pin 5 while being locked to the stopper block 6. Project by a predetermined amount. In the meantime, the fixed-side pushing pin 4 moves the edge of the product on the pushing surface 4E to the movable mold 3.
Hold it pressed to the side.

Subsequently, when the movable die 3 moves, as shown in FIG. 5, the movable push pin 5 relatively protrudes from the mold dividing surface of the movable die 3 as shown in FIG. The movable extrusion pin 5 removes the product from the movable mold 3 by extruding the edge of the product on the extrusion surface 5E at the tip end surface. At this time, the movable push-out pin 5 projects by a predetermined amount until the movable push-out pin 5 is stopped by the stopper block 8 with the contact face 5D kept in contact with the contact face 4D of the fixed push-out pin 4. In the meantime, the movable-side pushing pin 5 holds the state where the edge of the product is sandwiched between the pushing face 5E and the pushing face 4E of the fixed-side pushing pin 4.

When the movable mold 3 is further moved, as shown in FIG. 6, the movable extrusion pin 5 is separated from the fixed extrusion pin 4 as shown in FIG. Is locked. Therefore, when the base end of the pusher pin 10 shown in FIG. 1 is pressed by an appropriate jig (not shown), the tip protrudes from the mold dividing surface of the movable mold 3 to extrude the molding resin of the runner R portion. The product is completely removed from the mold.

That is, the injection mold 1 of the first embodiment.
According to this, the fixed-side pushing pin 4, which is spring-biased by the coil spring 7 so as to be able to protrude from the mold splitting surface and is prevented from coming off by the stopper block 6, is attached to the fixed mold 2, and the coil spring 9 sets the metal. With a simple additional structure in which the movable extrusion pin 5 that is spring-biased so as to protrude from the mold division surface and is prevented from coming off by the stopper block 8 is attached to the movable mold 3, the mold of the injection mold 1 is opened. The accompanying product can be easily removed from the mold, and the manufacturing cost of the injection mold 1 can be greatly reduced. In addition, the final product can be removed from the movable mold 3 without fail. In particular, since a molding mark by the fixed-side extrusion pin 4 and the movable-side extrusion pin 5 is not attached to the edge of the product, a product having a good appearance can be molded.

Next, a second embodiment of the present invention will be described with reference to FIGS.
The injection mold according to the embodiment will be described. In the drawings to be referred to, FIG. 7 is a cross-sectional view of an injection molding die according to a second embodiment, and FIG. 8 is a front view showing a mold dividing surface of a fixed mold of the injection molding die according to the second embodiment. FIG. 9 is a front view showing a mold dividing surface of a movable mold of the injection mold according to the second embodiment.

As shown in FIGS. 7 to 9, the injection molding die 20 according to the second embodiment comprises a pair of left and right products formed by injection molding in cavities C, C between a fixed die 21 and a movable die 22. The sprue S provided in the fixed die 21 is provided with a cavity C, C from a runner R through each gate G.
Is in communication with Injection mold 20 of the second embodiment
Also, since the configuration is basically the same as that of the injection mold 1 of the first embodiment, the same components are denoted by the same reference numerals, and detailed description is omitted. Only different components are detailed. Will be described.

In the injection molding die 20 of the second embodiment, the fixed-side push pin 4 and the movable-side push pin 5 are arranged to face each other near the edges of the products formed in the cavities C and C. . The place of the arrangement is the injection mold 20
Are set at two places near the central portion of the short side of. The fixed-side push pin 4 and the movable-side push pin 5 are spring-biased by coil springs 7 and 9, respectively, and are prevented from coming off by stopper blocks 6 and 8, so that the amount of protrusion from the mold dividing surface becomes a predetermined amount. Regulated. The fixed-side push pin 4 and the movable-side push pin 5 have respective contact surfaces 4D and 5D formed on the distal end surfaces thereof, and the product push surfaces 4F and 5F are continuous with the edges of the product. Each is formed as a part of the cavity surface corresponding to the meat portion. Extrusion surface 4F of fixed-side extrusion pin 4
Is formed as a flat surface that is continuous with the contact surface 4D, and the pushing surface 5F of the movable pushing pin 5 is formed as a rectangular recess that is recessed from the contact surface 5D.

In the injection mold 20 according to the second embodiment, as shown in FIGS. 7 and 8, a fixed-side projecting pin 23 is attached to the fixed mold 21. As shown in FIGS. 7 and 9, a movable-side protruding pin 24, a second movable-side push-out pin 25, and a pusher pin 26 are attached to the movable mold 22.

The fixed-side protruding pins 23 on the fixed mold 21 are provided at two places at the center in the longitudinal direction of the fixed mold 21 at a predetermined interval. The fixed-side protruding pin 23 has the same configuration as the fixed-side push-out pin 4. That is, the fixed-side protruding pin 23 is spring-biased by a coil spring 27 so as to be able to protrude from the mold dividing surface of the fixed die 21 as shown in FIG. 7, and by a stopper block 28 as shown in FIG. It is prevented from falling off and the amount of protrusion from the mold dividing surface is regulated to a predetermined amount. The tip surface of the fixed-side projection pin 23 is formed flat as a contact surface with the tip surface of the movable-side projection pin 24.

The movable-side protruding pins 24 of the movable mold 22 are slidably fitted to two central portions of the movable mold 22, respectively. When the mold 20 is in the closed state, the fixed side projecting pin 2
3 is in contact with the tip surface. The second movable-side push-out pins 25 are slidably fitted at four places at the center of the movable mold 22 at predetermined intervals from each other, and the distal end surface thereof is circular in the edge of the product. In order to form a recess, the tip of the cavity pin 29 implanted in the fixed mold 21 is opposed to the tip end of the cavity pin 29 at a predetermined interval. Further, the pusher pin 26
Is slidably fitted to the center of the movable mold 22, and the molding resin of the runner R can be extruded from the mold division surface of the movable mold 22 by the tip end surface facing the runner R. It is configured.

The movable protruding pin 24, the second movable push pin 25, and the pusher pin 26 are slidably fitted in a recess on the back side of the movable mold 22.
0 are fixed at their base ends, respectively.
It is configured to be slidable in the axial direction together with 0. The sliding block 30 is prevented from falling off by a support block 31 fitted and fixed in the opening of the concave portion, and a coil spring 32 interposed between the slide block 30 and the support block 31 divides the mold surface of the movable mold 22. Spring biased to the side. The movable-side protruding pin 24, the second movable-side pushing pin 25, and the pusher pin 26 are
By being spring-urged toward the mold dividing surface side of the movable mold 22 via the “0”, each of the distal end surfaces is configured to be able to protrude from the mold dividing surface of the movable mold 22 by a predetermined amount.

Here, the strength of the coil spring 32 is set to be lower than the strength of the coil spring 27 for urging the fixed-side protruding pin 23 on the fixed die 21 side.
In the closed state of the injection molding die 20 shown in FIG.
Support block 3 via movable side projecting pin 24 which contacts
It is pressed to one side.

According to the injection molding die 20 of the second embodiment configured as described above, in the closed state shown in FIG. 7, the sprue S of the fixed die 21 passes through the runner R and the respective gates G to the left and right. The molding resin material in a molten state is injected into the cavities C, C of the
The product is molded in. At this time, between the extrusion surface 4F of the fixed-side extrusion pin 4 and the extrusion surface 5F of the movable-side extrusion pin 5, a waste portion continuous to the edge of the product is formed.

When the movable mold 22 starts moving in the direction away from the fixed mold 21 in accordance with the mold opening after the injection molding of the product, first, each fixed-side pushing pin 4 and each fixed-side protruding pin 23 are fixed. It protrudes from the mold dividing surface of the mold 21 by a predetermined amount. In the meantime, each fixed side extrusion pin 4 removes a product from the fixed mold 21 by extruding a waste portion that is continuous with the edge of the product on the extrusion surface 4F at the tip end surface. In addition, each fixed-side protruding pin 23 restricts the movable-side protruding pin 24 from projecting from the mold dividing surface of the movable mold 22 by pressing the distal-side surface of the movable-side protruding pin 24 with its distal end surface.

Subsequently, when the movable mold 22 moves, each movable side pushing pin 5 protrudes from the mold dividing surface of the movable mold 22 by a predetermined amount relatively. Further, the movable-side protruding pin 24 relatively protrudes from the mold dividing surface of the movable mold 22, and in conjunction with this, the second movable-side pushing pin 25 and the pusher pin 26 relatively move from the mold dividing surface of the movable mold 22. Project by a predetermined amount. Then, the extruded surface 5F of the distal end face of each movable side push pin 5 pushes out the waste meat portion continuous to the edge of the product, and the distal end face of each second movable side push pin 25 removes the circular concave portion of the edge of the product. The product is removed from the movable mold 22 by extruding and the pusher pin 26 extruding the molding resin in the runner R portion. In the meantime, each movable-side push pin 5 holds a state in which a waste portion of the product is sandwiched between its push face 5F and the push face 4F of the fixed push pin 4. Then, when the movable die 22 further moves, the movable-side pushing pin 5 is separated from the fixed-side pushing pin 4, and the product can be removed from the mold.

That is, the injection mold 2 of the second embodiment
According to No. 0, with a simple additional structure similar to that of the injection mold 1 of the first embodiment, it is possible to easily remove the product when the mold of the injection mold 20 is opened. 2
0 can significantly reduce the manufacturing cost. Also,
Demolding of the final product can be reliably performed as demolding from the movable die 22. In particular, since a molding mark formed by the fixed-side push pin 4 and the movable-side push pin 5 does not stick to a portion other than the waste portion continuous to the edge of the product, a product having a good appearance can be formed.

Next, an injection mold according to a third embodiment of the present invention will be described with reference to FIGS. In the drawings to be referred to, FIG. 10 is a cross-sectional view of an injection mold according to a third embodiment, and FIG. 11 is a front view showing a mold dividing surface of a fixed mold of the injection mold according to the third embodiment. 12 is the third
FIG. 2 is a front view showing a mold dividing surface of a movable mold of the injection mold according to the embodiment.

As shown in FIGS. 10 to 12, the injection mold 40 according to the third embodiment includes a fixed mold 41 and a movable mold 42.
And a mold for injection-molding the product into the cavity C between the fixed mold 41 and the fixed mold 41 is provided with a sprue S communicating with the cavity C. Since the injection mold 40 of the third embodiment is also basically configured in the same manner as the injection mold 1 of the first embodiment, the same components are denoted by the same reference numerals and detailed. Detailed description will be omitted, and only different portions will be described in detail.

In the injection molding die 40 of the third embodiment, the fixed-side pushing pin 4 is arranged near the edge of the product molded in the cavity C, and the movable-side pushing pin 5 is attached to the edge of the product. They are arranged with their tip surfaces facing each other. The two locations are set in the vicinity of each side of the injection mold 40 except for one short side. The fixed-side push pin 4 and the movable-side push pin 5 are spring-biased by coil springs 7 and 9, respectively, and are prevented from coming off by stopper blocks 6 and 8, so that the amount of protrusion from the mold dividing surface becomes a predetermined amount. Regulated. Further, a contact surface 4 </ b> D with the movable-side push pin 5 is formed as a flat surface on the distal end surface of the fixed-side push pin 4. In addition, a contact surface 5D with the fixed-side extrusion pin 4 and a product extrusion surface 5G are formed as mutually continuous flat surfaces on the tip end surface of the movable-side extrusion pin 5, and the extrusion surface 5G is formed on the edge of the product. It constitutes a part of the cavity surface corresponding to a part of the end face.

According to the injection molding die 40 of the third embodiment configured as described above, in the mold closed state shown in FIG. 10, the molding resin in the molten state from the sprue S of the fixed die 41 into the cavity C. By being injected, a product is formed in the cavity C. Then, when the movable mold 42 moves in a direction away from the fixed mold 41 in accordance with the mold opening after the injection molding of the product, first, each fixed side pushing pin 4 projects by a predetermined amount from the mold dividing surface of the fixed mold 41. I do. In the meantime, each fixed side pushing pin 4 presses the contact surface 5D of each movable side pushing pin 5 with its contact surface 4D so that each movable side pushing pin 5 protrudes from the mold dividing surface of the movable mold 42. Regulate what you do.

Subsequently, when the movable die 42 moves, each of the movable-side pushing pins 5 protrudes from the mold dividing surface of the movable die 42 by a predetermined amount. The product is removed from the movable mold 42 by extruding the end face of the product adhered to the cavity C of the movable mold 42 by the pushing surface 5G of each movable-side pushing pin 5. Then, when the movable mold 42 further moves, the movable-side pushing pin 5 is separated from the fixed-side pushing pin 4, and the product can be removed from the mold.

That is, the injection molding die 4 of the third embodiment
According to No. 0, with the simple additional structure similar to the injection molding die 1 of the first embodiment, it is possible to easily perform the demolding of the product when the injection molding die 40 is opened. 4
0 can significantly reduce the manufacturing cost. Also,
Demolding of the final product can be reliably performed as demolding from the movable die 42. In particular, since a molding mark by the movable side push pin 5 does not stick to a part other than a part of the edge of the product, a product having a good appearance can be formed.

Next, an injection mold according to a fourth embodiment of the present invention will be described with reference to FIGS. In the drawings to be referred to, FIG. 13 is a cross-sectional view of an injection molding die according to a fourth embodiment, and FIG. 14 is a perspective view of an extrusion insert and a movable die that constitute main parts of the injection molding die according to the fourth embodiment. FIG.

As shown in FIGS. 13 and 14, the injection mold 50 of the fourth embodiment comprises a fixed mold 51 and a movable mold 52.
And a mold for injection-molding a product in the cavities C, C, between which the sprue S provided in the fixed mold 51 communicates with the cavities C, C from the runner R via the respective gates G. . In the description of the injection mold 50 of the fourth embodiment, the same components as those of the injection mold 1 of the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. Only different portions will be described. This will be described in detail.

In the injection molding die 50 of the fourth embodiment, a fixed-side pushing pin 4 as a fixed-side pushing member is attached to a fixed mold 51, and an extrusion insert 53 as a movable-side pushing member is attached to a movable mold 52. It is attached. The fixed side pushing pin 4 is spring-biased by a coil spring 7 so as to be able to protrude from the mold dividing surface of the fixed mold 51, and is prevented from coming off by the stopper block 6 so that the projecting amount from the mold dividing surface is a predetermined amount. Is regulated. The fixed-side push pins 4 are arranged on both sides of the center of the fixed mold 51 in the longitudinal direction, near the edges of the products formed in the cavities C, C. As shown in FIG. 13, a contact surface 4 </ b> D with the extrusion insert 53 is formed as a flat surface on the distal end surface of the fixed-side extrusion pin 4.

On the other hand, the extrusion insert 53 is formed in a block shape having a predetermined width and a sectional shape shown in FIG.
As shown in FIG. 14, the movable mold 52 is fitted into the central portion in the longitudinal direction. On the surface of the extrusion insert 53,
The runner R and the respective gates G are formed at the center thereof, and extrusion surfaces 53A of the product are formed at both sides thereof as a part of the cavity surface corresponding to the center of the rear surface of the product. On the surfaces of both ends of the extrusion insert 53, contact surfaces 53B with the fixed-side extrusion pins 4 are provided.
53B is formed as a flat surface.

In order to urge the pushing insert 53 so that it can protrude from the mold dividing surface of the movable mold 52 by a predetermined amount, a pair of movable push pins 5 are provided at both ends of the pushing insert 53.
4, 54 are connected to each other. Each movable side push pin 54 is inserted into a guide hole 52A formed in the movable mold 52 via a coil spring 55, and is constantly urged toward the push insert 53 side. The strength of the coil spring 55 is set to be weaker than the strength of the coil spring 7 for urging the fixed-side pushing pin 4 on the fixed die 51 side.

In order to regulate the amount of protrusion of the pushing insert 53 by the pair of movable side pushing pins 54, 54 to a predetermined amount,
A stopper bolt 56 is screwed and fixed to the base end of each movable side push pin 54. The stopper bolt 56 is provided in the recess 5 formed on the rear side of the movable mold 52.
2B through the movable mold 52 and the movable side pushing pin 5
4 is screwed and fixed to the base end thereof, and its head 5
6A contacts the bottom of the recess 52B so that the protrusion of the pusher 53 is regulated to a predetermined amount.

According to the injection mold 50 of the fourth embodiment configured as described above, in the closed state shown in FIG. 13, the cavity is formed from the sprue S of the fixed mold 51 via the runner R and each gate G. By injecting the molding resin in a molten state into C, C, a product is formed in the cavities C, C. When the movable mold 52 moves in a direction away from the fixed mold 51 in accordance with the mold opening after the injection molding of the product, first, the pair of fixed-side extrusion pins 4 are moved by a predetermined amount from the mold dividing surface of the fixed mold 51. Protrude. Meanwhile, the pair of fixed-side push pins 4, 4 press the contact surfaces 53B, 53B of the push insert 53 with the contact surfaces 4D, 4D, so that the push insert 53 separates the movable mold 52 from the mold. Restricts protrusion from the surface.

Subsequently, when the movable die 52 moves, the pusher 53 protrudes from the mold dividing surface of the movable die 42 by a relatively predetermined amount. Then, the extrusion surface 53 of the extrusion insert 53
A, 53A pushes out the center of the back surface of the product adhered to the cavities C, C of the movable mold 52, thereby forming the movable mold 52.
Remove the product from the mold. Then, when the movable mold 52 further moves, the pushing insert 53 is separated from each fixed-side pushing pin 4 to enable the product to be removed from the mold.

That is, the injection mold 5 of the fourth embodiment
According to 0, the fixed-side pushing pin 4 which is spring-biased by the coil spring 7 so as to be able to protrude from the mold splitting surface and is prevented from coming off by the stopper block 6 is attached to the fixed mold 51 and the coil spring 55 With a simple additional structure in which an extruding insert 53, which is spring-biased so as to be able to protrude from the mold dividing surface via a movable-side extruding pin 54 and whose amount of protrusion is restricted by a stopper bolt 56, is attached to the movable mold 52. In addition, the product can be easily removed with the opening of the injection mold 50, and the injection mold 5 can be easily removed.
0 can significantly reduce the manufacturing cost. Also,
Demolding of the final product can be reliably performed as demolding from the movable die 52. In particular, since a molding mark due to the extrusion insert 53 does not stick to a part other than a part of the back surface of the product, a product having good appearance can be molded.

[0058]

As described above, in the injection molding die according to the first aspect of the present invention, as the product is opened after the injection molding of the product, the fixed side extruding member is divided by the spring biasing force into the fixed die. The movable side pushing member protrudes from the movable mold splitting surface by a spring biasing force. Then, at least the movable die extruding member removes the product from the die by extruding the product adhered to the movable die on the extrusion surface. That is, according to the injection mold of the first invention, the fixed-side extruding member and the movable-side extruding member which are spring-biased so as to protrude from the mold dividing surface and are prevented from falling off are attached to the fixed mold and the movable mold. With this simple additional structure, the product can be easily removed from the mold when the mold is opened, and the manufacturing cost of the mold can be significantly reduced.

In the injection mold according to the second aspect of the present invention, as the product is opened after the injection molding of the product, first, the fixed-side extruding member having a stronger spring biasing force than the movable-side extruding member is divided into a fixed mold divided. Then, the movable extrusion member projects from the mold dividing surface of the movable mold. Then, at least the movable-side extruding member surely removes the product from the mold by extruding the product adhered to the movable mold on the extruded surface. That is, according to the injection mold according to the second invention, the same operation and effect as those of the injection mold according to the first invention are obtained, and the final product is removed from the movable mold. Can be performed reliably.

In the injection mold according to the third aspect of the present invention, as the product is opened after the injection molding of the product, the fixed-side pushing pin projects from the fixed mold dividing surface by the biasing force of the spring.
The movable-side push pin protrudes from the movable mold dividing surface by the biasing force of the spring. Then, the fixed-side push pin and the movable-side push pin remove the product from the fixed mold and the movable mold by extruding the edge of the product with the extrusion surface formed on the tip surface. That is, according to the injection molding die according to the third invention, the same operation and effects as those of the injection molding die according to the first invention and the second invention can be obtained, and in particular, the fixed side extrusion pin and the movable side Since a molding mark due to the extrusion pin does not stick to other than the edge of the product, a product having good appearance can be molded.

In the injection mold according to the fourth aspect of the present invention, as the product is opened after the injection molding of the product, the fixed-side pushing pin projects from the fixed mold dividing surface by the biasing force of the spring.
The movable-side push pin protrudes from the movable mold dividing surface by the biasing force of the spring. Then, the fixed-side push pin and the movable-side push pin remove the product from the fixed mold and the movable mold by extruding a waste portion that is continuous with the edge of the product on the extrusion surface formed at the tip end surface. That is, according to the injection molding die according to the fourth invention, the same operation and effects as those of the injection molding die according to the first invention and the second invention can be obtained, and in particular, the fixed side extrusion pin and the movable side Since molding marks due to the extruded pins do not stick to portions other than the waste portion, a product having a good appearance can be formed.

In the injection molding die according to the fifth aspect of the invention, as the product is opened after the injection molding of the product, the fixed-side pushing pin projects from the fixed mold dividing surface by the biasing force of the spring.
The movable-side push pin protrudes from the movable mold dividing surface by the biasing force of the spring. The movable extrusion pin removes the product from the movable die by extruding the edge end surface of the product adhered to the movable die with the extrusion surface formed on the tip end surface. That is, according to the injection molding die according to the fifth invention, the same operation and effect as those of the injection molding die according to the first invention and the second invention can be obtained, and particularly, the molding mark by the movable side extrusion pin. Also, since it does not adhere to the edge other than the edge of the product, a product having a good appearance can be formed.

In the injection molding die according to the sixth aspect of the present invention, as the product is opened after the injection molding of the product, the fixed-side extrusion pin projects from the mold dividing surface of the fixed die by a spring urging force.
The pushing insert protrudes from the mold separation surface of the movable mold due to the biasing force of the spring. Then, the extrusion insert removes the product from the movable die by extruding a predetermined portion of the back surface of the product adhered to the movable die with the extrusion surface formed on the surface. That is, according to the injection mold according to the sixth invention, the first
The same operation and effects as those of the injection molds according to the inventions and the second invention can be obtained, and in particular, since molding marks due to extrusion inserts do not stick to other than the back surface of the product, a product having a good appearance is molded. be able to.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an injection mold according to a first embodiment of the present invention.

FIG. 2 is a front view showing a mold dividing surface of a movable mold of the injection molding mold according to the first embodiment.

FIG. 3 is a perspective view of a fixed-side extrusion pin and a movable-side extrusion pin that constitute main parts of the injection molding die according to the first embodiment.

FIG. 4 is a partial cross-sectional view showing a first stage of operation of a fixed-side extrusion pin and a movable-side extrusion pin of the injection molding die according to the first embodiment.

FIG. 5 is a partial cross-sectional view showing a second stage of the operation of the fixed-side extrusion pin and the movable-side extrusion pin of the injection molding die according to the first embodiment.

FIG. 6 is a partial sectional view showing a third stage of the operation of the fixed-side extrusion pin and the movable-side extrusion pin of the injection molding die according to the first embodiment.

FIG. 7 is a cross-sectional view of an injection mold according to a second embodiment of the present invention.

FIG. 8 is a front view showing a mold dividing surface of a fixed mold of the injection mold according to the second embodiment.

FIG. 9 is a front view showing a mold dividing surface of a movable mold of an injection mold according to a second embodiment.

FIG. 10 is a transverse sectional view of an injection mold according to a third embodiment of the present invention.

FIG. 11 is a front view showing a mold dividing surface of a fixed mold of an injection mold according to a third embodiment.

FIG. 12 is a front view showing a mold division surface of a movable mold of an injection mold according to a third embodiment.

FIG. 13 is a longitudinal sectional view of an injection mold according to a fourth embodiment of the present invention.

FIG. 14 is a perspective view of an extrusion insert and a movable mold that constitute main parts of an injection mold according to a fourth embodiment.

[Explanation of symbols]

 1: Injection molding die 2: Fixed mold 3: Movable mold 4: Fixed side extrusion pin 4D: Contact surface 4E: Extrusion surface 4F: Extrusion surface 5: Movable extrusion pin 5D: Contact surface 5E: Extrusion surface 5F: Extruded surface 5G: Extruded surface 6: Stopper block 7: Coil spring 8: Stopper block 9: Coil spring 20: Injection mold 21: Fixed mold 22: Movable mold 40: Injection mold 41: Fixed mold 42: Movable mold 50: Injection mold 51: Fixed mold 52: Movable mold 53: Extrusion insert 54: Movable extrusion pin 55: Coil spring 56: Stopper bolt C: Cavity

Claims (6)

[Claims] 1. A mold for injection-molding a product into a cavity between a fixed mold and a movable mold, wherein the fixed mold is spring-biased so as to protrude from a mold dividing surface thereof and is prevented from falling off. The movable die is attached to the movable die, and the movable die is provided with a movable extrusion member that is spring-biased so as to protrude from the mold division surface and is prevented from falling off. Both the movable side extruding members are formed with contact surfaces that abut each other when the mold is closed. At least the movable side extruding member has an extruding surface capable of extruding a product as the mold is opened. An injection mold characterized by being formed. 2. The injection molding die according to claim 1, wherein a spring biasing force of the fixed-side pushing member is set to be stronger than a spring biasing force of the movable-side pushing member. Mold. 3. The injection mold according to claim 1, further comprising: a fixed-side push pin as the fixed-side push member; and a movable-side push pin as the movable-side push member. The push-out pin and the movable push-out pin are arranged such that a tip end face is opposed to an edge of a product to be injection-molded, and the tip end face is formed with the contact surface, respectively, and the push-out face is An injection molding die formed as a part of a cavity surface corresponding to a part of an edge of a product. 4. The injection mold according to claim 1, further comprising: a fixed-side pushing pin as the fixed-side pushing member; and a movable-side pushing pin as the movable-side pushing member. The extrusion pin and the movable-side extrusion pin are opposed to each other in the vicinity of the edge of the product to be injection-molded, and the abutting surfaces are formed on the end surfaces thereof, respectively, and the extrusion surface corresponds to the edge of the product. Injection molding dies, each of which is formed as a part of a cavity surface corresponding to a waste portion that is continuous with the mold. 5. The injection mold according to claim 1, further comprising: a fixed-side pushing pin as the fixed-side pushing member; and a movable-side pushing pin as the movable-side pushing member. The extrusion pin is disposed near the edge of the product to be injection molded, and the movable extrusion pin is
The distal end face is arranged to face the edge of the product to be injection-molded, the contact face is formed on the distal end face of the fixed-side extrusion pin, and the distal end face of the movable-side extrusion pin is The injection molding die, wherein the contact surface is formed, and the extruded surface is formed as a part of a cavity surface corresponding to a part of an end face of the product. 6. The injection molding die according to claim 1, further comprising: a fixed-side pushing pin as the fixed-side pushing member; and an extrusion insert as the movable-side pushing member. The extrusion pin is arranged near the edge of the product to be injection-molded, and the contact surface is formed on the tip surface thereof, and the contact surface is formed on the surface of the extrusion insert, In addition, the extrusion surface is formed as a part of a cavity surface corresponding to a predetermined portion of a back surface of the product.