JP2987150B1 - Type structure - Google Patents

Abstract

A simple configuration increases the degree of freedom in designing a product having an undercut portion. When an upper mold (34) is moved from a molding position shown in a mold opening direction (A) by an actuator (42), an interlocking rod (46) and a slide hole (38) inclined with respect to the mold opening direction.
B moves the lower slide portion 38 from the illustrated molding position in the mold release direction B. Thereafter, the resin molded product 10 is moved in a die removing direction parallel to the mold opening direction, and the actuator 4
8, the upper slide portion 40 is moved from the molding position in the releasing direction. As a result, the fixed die 32 and the slide portion 3
8, 40 and the upper die 34 do not interfere with the resin product 10 moving in the die-cutting direction, and the resin molded product 10 can be die-cut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a product having an undercut by providing a first protrusion at a different position and a second protrusion protruding in a direction approaching the first protrusion. The present invention relates to a mold structure for molding a resin from a resin or the like.

[0002]

2. Description of the Related Art In a mold structure in which a molten resin or the like is injected and solidified between a pair of main molding dies to form a product, there are two projecting portions in directions approaching each other to different portions of the product. Is to extract a part of the product by elastically deforming it (Japanese Utility Model Laid-Open No. 3-116907), or to separate a part of the main mold with a molding surface between these parts from a pair of main molds. It is necessary to use a split type or a slide type.
issue).

[0003]

However, when the product is elastically deformed and pulled out, that is, in the case of so-called forced pulling,
If the amount of deformation of the product is excessive, plastic deformation or damage such as linear marks will occur. Therefore, the amount that can bend and deform a part of the product (maximum bending amount) depends on the characteristics of the resin used as the material and the product. The specification of the product must be changed so as not to be restricted according to the thickness of the product, or to cause a problem in the product, thereby reducing the degree of freedom in product design. Further, when a plurality of split dies are used to form such a protruding portion, the driving mechanism of the split die is complicated and the life of the die is short, and a long stroke is required to open the die, and the molding time is long. There was a problem.

[0004] An object of the present invention is to provide a mold structure capable of increasing the degree of freedom in designing a product having an undercut portion with a simple configuration in consideration of the above fact.

[0005]

According to a first aspect of the present invention, there is provided a mold structure, wherein a product molding cavity is formed between a first molding die and the first molding die, and the first molding die is formed when the product is taken out. A second mold that moves relative to the mold in the mold opening direction; and a mold surface that molds a first protrusion of the product, and a mold release direction that intersects the mold opening direction with respect to the first mold. A first slide mold which is released from the first projecting portion to move a product in a direction of removing the product from the product molding cavity; and a first projection of the product. A molding surface for molding a second protrusion protruding in a direction approaching the part, the mold being movable in the release direction separately from the first slide mold, and a mold after movement of the first slide mold. Moves in the release direction by moving the product in the pull-out direction away from the second protrusion of the product And a second slide die that is retracted from the removal trajectory of the first protrusion by this movement.

According to the above-described mold structure, the first molding die and the second molding die are opened after the product material injected into the product molding cavity is solidified, and the first slide die is separated. When the molding surface is moved in the mold direction to release the molding surface from the first protrusion of the product, the first slide die does not interfere with the product, and the product can be moved in the mold removal direction. After that, by moving the product in the die removing direction, the second protrusion does not interfere with the second slide mold or the amount of interference of the second protrusion with the second slide mold can be sufficiently reduced. 2 can be moved in the releasing direction. Therefore, if the second slide die is moved in the release direction and retracted from the removal trajectory of the first protrusion, the die can be removed without elastically deforming the product, or the die can be deformed only by slightly elastically deforming the product. Can be pulled out.

Here, the mold opening direction is defined as such a value that the distance between the joining surface of the first molding die and the joining surface of the second molding die, which were in contact with each other at the time of product molding, is increased for taking out the product.
This is the moving direction of the first or second molding die. Also, the mold release direction refers to the movement of the product for removing the product from either the first mold or the second mold after the first and second molds are relatively moved in the mold opening direction. Direction. The separating direction is different from the mold opening direction, and may be any direction as long as the first slide die and the second slide die are separated from the product. Therefore, it is not always necessary to translate the first slide mold and the second slide mold in the same direction.

According to a second aspect of the present invention, in the mold structure according to the first aspect, the first molding die forms a leg protruding from a main body at the time of molding the product, and the leg is formed after the product is molded. Until the part is pulled out, the product has a concave portion that restricts the moving direction of the product so that the product can move only in the die removing direction.

According to the above-structured mold structure, the first mold and the second mold are opened after the product material is solidified, and the first mold is opened.
By moving the slide die in the mold release direction to separate the molding surface from the first protrusion of the product, the first slide die does not interfere with the product, and the product can be moved in the die removal direction. After that, the product is moved in the die-cutting direction until the second protrusion does not interfere with the second slide die, so that the second slide die can be moved in the release direction. Therefore, if the second slide die is moved in the release direction and retracted from the removal trajectory of the first protrusion, the concave portion of the first molding die limits the movement direction of the product to only the mold opening direction. Even in the state, the product can be die-cut.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a mold structure according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 5 shows an example of a sectional shape of a resin product used as a door knob for an automobile. The resin product 10 has a thin plate-shaped main body 12.
A bent portion 13 having a constant thickness is formed at one end of the main body 12 so as to have a convex curved surface on the upper surface side and a concave curved surface on the lower surface side. A pair of parallel legs 14 and 16 protruding downward is provided on the lower surface of the main body 12. These pair of legs 1
The longitudinal directions of the legs 4 and 16 are parallel to each other, and the tip of one leg 16 is in a direction different from the longitudinal direction. An undercut projection 18 is formed to narrow the entrance of the cavity 17 to be formed.

When the resin product 10 having the bent portion 13 and the protruding portion 18 is molded from a resin as described above, for example, as shown by a two-dot chain line in FIG.
The upper mold 24 is movable from the illustrated molding position in the mold opening direction (the direction of arrow A), and is substantially perpendicular to the mold opening direction from the illustrated molding position and substantially parallel to the projecting direction of the projecting portion 18. It is conceivable to use a dividable mold structure 20 including a slide mold 26 that is movable in a mold release direction (arrow B direction). However, since the bent portion 13 and the protruding portion 18 in the undercut state are formed in the resin molded product 10, the resin molded product 10 is moved in the longitudinal direction of the legs 14 and 16 when the slide die 26 is in the molding position. Can not move in the die-cutting direction along. When the slide die 26 is moved in the release direction, the slide die 26 must be moved in the release direction while forcibly bending the bent portion 13 of the resin product 10 upward (in the direction of arrow C). Therefore, it is impossible to mold the resin product 10 using a general slide mold.

FIGS. 1 to 4 show a mold structure 30 according to an embodiment of the present invention, in which the resin product 10 described with reference to FIG. 5 is molded.

The mold structure 30 has a fixed mold 32, an upper mold 34, and a slide mold 36, and is a divisible structure.
The upper mold 34 and the slide mold 36 are formed at the molding positions that are in contact with each other as shown in FIG. 1, and are formed in a hollow portion corresponding to the outer shape of the resin product 10 together with the fixed mold 32 before the injection of the molten resin starts. Form a molding cavity.

The upper mold 34 can be moved from the molding position in the mold opening direction (the direction of arrow A) and can be separated from the fixed mold 32. Since the resin product 10 has the legs 14, 16 projecting parallel to each other, the resin product 10 is parallel to the mold opening direction from the fixed mold 32 in the mold opening state (FIGS. 2 to 4) in which the upper mold 34 moves in the mold opening direction. It is designed to be moved in the direction of die release and taken out. The upper mold 34 has a molding surface 34A for molding the upper surface side of the main body 12 of the resin product 10.

The slide die 36 has a lower slide portion 38 and an upper slide portion 40 which are stacked and arranged in the mold opening direction.
And Guide parts (not shown) are provided on the mold structure 30, and these slide parts 38 and 40 cannot move in the mold opening direction from the molding position shown in FIG. It is possible to move independently of each other in the direction (arrow B direction). The upper slide portion 40 is provided with a molding convex surface 40A for molding the lower surface side of the bent portion 13 of the resin product 10, and the lower slide portion 38 is formed on the upper side of the protrusion 18 of the resin product 10. Is provided with a molding concave surface 38A.

The tip of a rod 44 of an actuator 42 is connected to the upper mold 34. The actuator 42 has an air cylinder 43 and a rod 44. When high-pressure air is supplied to the cylinder 43, the rod 42 is pushed out or retracted from the cylinder 43. Here, the actuator 42 holds the upper die 34 at the molding position when the rod 44 is pushed out as shown in FIG. 1, and by pulling the rod 44 from this state, as shown in FIG. The upper mold 34 is moved from the molding position in the mold opening direction.

The upper mold 34 is formed with a through hole 34B penetrating from the upper surface to the lower surface. A straight interlocking rod 46 having a round bar shape projects from the lower surface of the upper mold 34 and inclines in the releasing direction toward the lower end. I have. The lower end portion of the interlocking rod 46 is slidably inserted into the slide hole 38B of the lower slide portion 38 through the clearance groove 40B of the upper slide portion 40. At this time, even when the upper die 34 is moved by the actuator 42, the interlocking rod 46 can move from the molding position in the mold opening direction together with the upper die 34 without interfering with the upper slide portion 40 by the relief groove 40B.

The center axis of the slide hole 38B of the lower slide portion 38 is coaxial with the center axis of the interlocking rod 46, and has the same inclination angle. A protruding portion of the interlocking rod 46 from the upper slide portion 40 is slidably inserted into the slide hole 38B. Here, as shown in FIG. 1, when the interlocking rod 46 is in the molding position together with the upper mold 34,
The interlocking rod 46 is, as shown in FIG.
The leading end protrudes from the lower surface of the lower slide portion 38 toward the fixed die 32 through 8B, and reaches the cutout portion 32A of the fixed die 32.

The interlocking rod 46 slides in the slide hole 38B in conjunction with the movement of the upper mold 34 in the mold opening direction.
Interlock rod 46 and slide hole 38 in the mold opening direction
Since B is inclined, a component force is generated by the action of the inclined surface, and the lower slide portion 38 is moved in a direction to separate the molded concave surface 38A from the protruding portion 18 as shown in FIG. As a result, the protrusion 18 does not interfere with the lower slide portion 38, and the resin product 10 moves in the mold opening direction to a position where the protrusion 18 contacts the lower surface of the lower slide portion 40 as shown in FIG. Will be possible.

The mold structure 30 of the present embodiment is provided with a push-up mechanism (not shown) using a knockout pin for the resin product 10. The push-up mechanism operates after the actuator 42 retracts the rod 44 to move the resin product 10 in the die-cutting direction as shown in FIG.

The rod 50 of the horizontally arranged actuator 48 is connected to the upper slide portion 40. The actuator 48 is configured similarly to the actuator 42, and pushes or retracts the rod 48 from the cylinder 49 when high-pressure air is supplied to the cylinder 49. here,
The actuator 48 is connected to the rod 5 as shown in FIG.
In the state in which 0 is pushed out, the upper slide part 40 is held at the molding position, and by pulling the rod 50 from this state, the lower slide part 40 is moved from the molding position in the release direction as shown in FIG. Let it.

The fixed mold 32 is formed with a concave portion 32B for molding one leg 14 of the resin product 10. The concave portion 32B is formed such that its depth direction coincides with the die-cutting direction. Here, the leg portion 14 protrudes downward from the lower surface of the main body portion 12, and does not have an undercut portion that interferes with the concave portion 32B when moving in the mold opening direction. As a result, the leg 14 of the resin product 10 can move in the mold opening direction from inside the cavity 32B, but the resin product 10 is moved in the mold opening direction until the leg 14 completely comes out of the concave portion 32B. The movement direction is restricted by the leg portion 14 and the concave portion 32B so that only the movement is possible.

(Operation of the present embodiment) Next, the operation of the mold structure 30 according to the present embodiment will be described.

As shown in FIG. 1, the mold structure 30 is in a state in which the upper mold 34 and the slide portions 38 and 40 are held at the molding position, and the product material is melted through a gate for resin injection (not shown). Resin is injected. When the molten resin injected into the mold structure 30 cures, the actuator 42
High-pressure air is supplied to the cylinder 43. This allows
The actuator 42 retracts the rod 44 to move the upper mold 34 in the mold opening direction. At the same time, the lower slide portion 38 moves from the molding position in the release direction in conjunction with the movement of the upper mold 34. At this time, the upper mold 34 moves in the mold opening direction a distance sufficiently longer than the interference amount K (see FIG. 1) of the bent portion 13 to the upper slide portion 40. On the other hand, the lower slide portion 3
Numeral 8 moves from the movement locus (the two-dot chain line L in FIG. 2) of the tip of the protruding portion 18 when the resin product 10 moves in the die removing direction to the release direction side.

When the lower slide portion 38 moves to the release direction side from the removal locus L, the resin product 10 can move in the die release direction. In this state, the push-up mechanism operates the knockout pin to push up the resin product 10 in the die-cutting direction.
At this time, as shown in FIG. 3, the resin product 10 moves in the die-cutting direction by a distance slightly longer than the interference amount K by the knockout pin. Thus, the upper slide portion 40 can move in the detaching direction without being interfered by the bent portion 13 of the resin product 10.

When the resin product 10 moves from the molding position in a direction slightly longer than the interference amount K in the die removing direction, high-pressure air is supplied to the cylinder 49 of the actuator 48. Accordingly, as shown in FIG. 4, the actuator 48 retracts the rod 50 to move the upper slide portion 40 to the release direction side from the removal trajectory L of the protrusion 18. Thereafter, the actuator 42 moves the upper mold 34 further from the position shown in FIG. 4 in the mold opening direction, and sets the distance from the upper surface of the fixed mold 32 to the lower surface of the upper mold 34 along the releasing direction to the resin product 1.
0 is sufficiently longer than the length of the leg 14. As a result, the resin product 10 can be moved in the die removing direction until the leg portion 14 comes out of the concave portion 32B without being interfered by any of the fixed die 32, the slide portions 38 and 40, and the upper die 43. If the resin product 10 is moved linearly in the die-cutting direction, the resin product 10 can be die-cut from the die structure 30.

According to the mold structure 30 of the present embodiment described above, after the molten resin injected into the cavity is solidified, the upper mold 34 is moved in the mold opening direction, and the fixed mold 32 and the upper mold 3 are moved.
4 and the lower slide portion 38 is moved in the release direction to release the molded concave surface 38A from the projecting portion 18 of the resin product 10, and the lower slide portion 38 moves in the die release direction. This prevents the resin product 10 from interfering with the resin product 10 to be moved, and allows the resin product 10 to move in the die-cutting direction. Thereafter, the resin product 10 is moved in the die-cutting direction so that the resin product 1
The upper sliding portion 4 in which the bent portion 13 moves in the releasing direction.
0, so that the upper slide portion 40 can be moved in the releasing direction. Therefore, the upper slide portion 4
If the resin product 10 is moved to the release direction side from the removal trajectory L of the protruding portion 18 by moving 0 in the release direction, the resin product 10 can be die-cut without being elastically deformed. In this case, the resin product 10
Is linearly moved in the die removing direction and is extracted from the fixed die 32 and the slide dies 38 and 40, so that the resin product 10 can be removed even when the moving direction of the resin product 10 is restricted by the concave portion 32B of the fixed die 32. Can be die cut.

According to the mold structure 30 of the present embodiment, there is no need to forcibly remove the resin product 10, that is, it is not necessary to elastically deform the resin product 10 when removing the mold. Design flexibility can be increased.

In the description of the present embodiment, the case where the resin product 10 is die-cut without being elastically deformed has been described. However, since the bent portion 13 has a thin plate shape and has elasticity in the bending direction, Even if the bent portion 13 is slightly bent, the resin product 10 is not damaged. Therefore, the lower slide portion 3
Even if the push-up mechanism can move the resin product 10 only slightly less than the interference amount K (see FIG. 1) in the die-removing direction after the movable member 8 has moved to the release direction side from the removal trajectory L, 13 is slightly bent upward, the resin product 1
The upper slide portion 40 can be moved in the disengaging direction without damaging the upper portion.

In the mold structure 30 of the present embodiment, the actuator 42 is connected to the upper mold 34, and the lower slide portion 38 is detached in conjunction with the movement of the upper mold 34 in the mold opening direction by the actuator 42. Actuator 42 connected to the upper mold 34.
It is also possible to connect a separate actuator to the lower slide portion 38 and move the lower slide portion 38 in the release direction by the actuator without using the interlocking rod 46. Further, the actuators 42 and 48
The rods 44,
Although the one that drives the 50 is used, as long as the upper die 34 and the slide die 40 can be moved, one that drives the rod by a hydraulic cylinder or one that has a different structure such as an electromagnetic actuator can be applied.

In the description of the present embodiment, the case where the resin product 10 is molded using the mold structure 30 has been described. However, according to the mold structure to which the present invention is applied in the same manner as the mold structure 30, It is also possible to mold a metal product having an undercut similar to the resin product 10, and it is not necessary to forcibly remove the metal product. Can be larger.

[0033]

As described above, according to the mold structure of the present invention, the degree of freedom in designing a product having an undercut portion can be increased with a simple structure.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a mold structure and a resin product showing a state where an upper mold and a slide mold according to an embodiment of the present invention are at a molding position.

FIG. 2 is a cross-sectional view of a mold structure and a resin product showing a state in which an upper mold has moved in a mold opening direction and a lower slide portion has moved in a mold releasing direction from the state shown in FIG.

FIG. 3 is a cross-sectional view of the mold structure and the resin product showing a state where the resin product has moved in a die removing direction from the state shown in FIG. 2;

4 is a cross-sectional view of a mold structure and a resin product showing a state in which an upper slide portion has moved in a releasing direction from a state shown in FIG.

FIG. 5 is a cross-sectional view illustrating an example of a shape of a resin product molded using the mold structure according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 10 resin product (product) 13 bent portion (second projecting portion) 14 leg portion 17 cavity portion (cavity for molding) 18 projecting portion (first projecting portion) 30 mold structure 32 fixed mold (first molding mold) 32B concave shape Part 34 Upper die (second molding die) 36 Slide die 38 Lower slide part (first slide die) 38A Molded concave surface 40 Upper slide part (second slide die) 40A Molded convex surface

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B29C 33/44 B29C 45/44

Claims (2)

(57) [Claims] 1. A product molding cavity is formed between a first molding die and the first molding die, and a second molding die is moved relative to the first molding die in a mold opening direction when the product is taken out. And a molding surface for molding a first protrusion of the product.
The mold can be moved in a mold release direction that intersects with the mold opening direction. With this movement, the product can be released from the first projecting portion and moved in the mold removal direction from the product molding cavity. A first slide die, and a second projecting in a direction approaching the first projecting portion of the product.
A molding surface for molding the protruding portion, the molding surface being movable in the release direction independently of the first slide die, and the movement of the product in the die-cutting direction after the movement of the first slide die. (2) It can be moved away from the protrusion in the release direction,
A second slide die that retreats from the removal trajectory of the first protrusion by this movement. 2. The first molding die forms a leg protruding from a main body at the time of molding the product, and the product is moved only in the die removing direction until the leg is pulled out after molding the product. The mold structure according to claim 1, further comprising a concave portion that restricts a moving direction of the product so as to be movable.