JP2011025499A - Method of manufacturing resin molded body and insert core for molding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a resin molded body capable of suppressing occurrence of warp with a simple step and without increasing the step, and capable of preventing deformation of a complicated shaped resin molded body. <P>SOLUTION: In the method of manufacturing the resin molded body, the insert core which is removably disposed in a cavity of a molding mold with the resin molded body is disposed in the cavity to inject the resin. After opening the molding mold, the resin is cooled while keeping the shape of the resin molded body by the insert core composing a part of the cavity shape. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing a resin molded body and an insert insert for molding.

  When a resin is molded by injection molding, warping may occur due to molding distortion or the like. As a method of correcting the warp of the resin molded body, for example, in the case of a plate-shaped resin molded body, the plurality of plate-shaped resin molded bodies 1 in which warpage is generated are stacked so that the convex surfaces face each other and the concave surfaces face each other. Patent Document 1 discloses heating with a load applied from above.

JP 2005-153503 A

However, the conventional warp correction method is performed after the molding process, which increases the number of processes for correcting the warpage, leading to an increase in lead time and an increase in processing costs. It was hard to say.
Further, in the case of a plate-shaped resin molded body, it is possible to correct the warpage by stacking and applying a load or the like (Patent Document 1). However, there is a problem that more complicated warp correction is required for resin molded bodies having other shapes.

  Accordingly, the present invention provides a method for manufacturing a resin molded body and a molding insert insert that can suppress the generation of warpage without increasing the number of steps and that can prevent deformation of a resin molded body having a complicated shape. The purpose is to do.

In order to achieve the above object, a method for producing a resin molded body according to the present invention is a method for producing a resin molded body in which a resin molded body is taken out after injecting a resin into a cavity of a molding die,
After the mold is opened, cooling is performed while maintaining the shape of the resin molded body by a shape holding member constituting a part of the cavity shape.

  In the method for producing a resin molded body according to the present invention, the shape holding member can be constituted by an insert insert that is detachably disposed together with the resin molded body in the cavity of the molding die. Further, the method includes disposing the insert insert in the cavity of the molding die and injecting the resin into the cavity and then taking out and cooling the resin molded body together with the insert insert.

  In the method for producing a resin molded body according to the present invention, it is preferable that the temperature of the insert nest when the resin is injected into the cavity coincides with the temperature of the molding die.

  In the method for producing a resin molded body according to the present invention, before the insert insert is disposed in the cavity, the insert insert is preheated to a mold temperature of 1 to 3 ° C. when the resin is injected. It may further include raising.

  In the method for producing a resin molded body according to the present invention, the shape holding member is formed integrally with the molding die, cooled after the mold is opened, and then the resin molded body is removed from the shape holding member. You may do it.

  Further, the insert insert for molding according to the present invention is an insert insert that is detachably disposed with the resin molded body in the cavity of the molding die, and has a shape corresponding to a partial shape of the resin molded body. It is characterized by.

  The insert insert for molding according to the present invention may be divisible into two or more.

  The insert insert for molding according to the present invention is provided in the insert insert corresponding to at least a part of the convex portion when the partial shape of the molded body includes a convex portion, and a taper is formed in the concave portion. You may make it form.

  In the insert insert for molding according to the present invention, for example, when the resin molded body has a plate-like shape having two main surfaces and side surfaces facing each other, it opposes one main surface. The two side surfaces may be covered and further extended from the side surface to the outer periphery of a part of the other main surface.

The insert insert for molding according to the present invention may be configured to have a shape corresponding to the inner peripheral shape of the ring shape as the outer peripheral shape, for example, when the resin molded body has a ring shape. it can.
Moreover, the insert nest | insert may be formed so that it can be divided | segmented into two in the center axis direction of the said ring shape.

  In the method for producing a resin molded body according to the present invention as described above, after the molding die is opened, cooling is performed while maintaining the shape of the resin molded body by a shape holding member constituting a part of the cavity shape. Therefore, the generation of warp can be suppressed without increasing the number of steps, and deformation of the resin molded body having a complicated shape can also be prevented.

It is a perspective view of the resin molding 11 shape | molded using the insert nest | insert 1 of Embodiment 1 which concerns on this invention. FIG. 2 is a perspective view of the insert insert 1 according to the first embodiment that is disposed in a cavity of a molding die 12. It is a perspective view of the insert nest | insert 1 of Embodiment 1 taken out from the shaping | molding die in the state united with the resin molding 11. FIG. (A) is a side view of the insert nest | insert 1 of Embodiment 1, (b) is an enlarged view which expands and shows a part. In Embodiment 1, it is a see-through | perspective perspective view when the insert nest | insert 1 is fixed in the cavity of the shaping die 12. FIG. (A) is a perspective view which shows the state with which the resin molding 111 and the insert nest 101 of the modification which concern on this invention were united, (b) is a side view of the insert nest 101. FIG. It is a perspective view which shows the structure of the shaping die 22 of Embodiment 2 which concerns on this invention. In the shaping | molding method of Embodiment 3 which concerns on this invention, it is a perspective view of the insert nest | insert 3 taken out from the shaping die in the state united with the resin molding 31. FIG. In the molding method of Embodiment 3 which concerns on this invention, it is a see-through | perspective perspective view when the insert nest | insert 3 is fixed in the cavity of the shaping die 32. FIG. FIG. 10 is a cross-sectional view of FIG. 9. (A) is the perspective view of the insert nest | insert 4 taken out from the shaping die 42 in the state united with the resin molding 41 in the shaping | molding method of Embodiment 4 which concerns on this invention, (b) is an insert nest | insert. 4 is a perspective view of FIG. In the molding method of Embodiment 4, it is a see-through | perspective perspective view when the insert nest | insert 4 is fixed in the cavity of the shaping die 42. FIG.

Embodiment 1. FIG.
The first embodiment according to the present invention relates to a method of manufacturing a resin molded body for manufacturing a resin molded body 11 as a final product using the insert insert 1. In the method of the first embodiment, the mold of the mold 12 is fixed. An insert nest 1 is used that is placed in the tee.
Here, in particular, the insert insert 1 of the first embodiment is detachably disposed together with the resin molded body 11 in the cavity of the molding die 12, and is taken out from the molding die 12 together with the resin molded body 11. It is comprised so that it can remove from the molded object 11. FIG.
Further, the insert insert 1 according to the first embodiment has a shape corresponding to a partial shape of the resin molded body 11, and the insert insert 1 is molded by being disposed in the cavity of the molding die 12. The cavity of the mold 12 and the insert insert 1 constitute a resin molded body cavity corresponding to the resin molded body 11 as the final product.
Furthermore, after molding, the insert insert 1 is taken out together with the resin molded body 11 from the molding die 12 and prevents the resin molded body from being deformed until the resin molded body 11 is cooled.

Hereinafter, Embodiment 1 according to the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a resin molded body 11 molded using the insert insert 1 according to the first embodiment of the present invention, and FIG. 2 shows the insert insert 1 disposed in the cavity of the molding die 12. FIG. 3 is a perspective view of the insert insert 1 taken out from the molding die 12 in a state where it is combined with the resin molded body 11.

  In the first embodiment, as shown in FIG. 1, the resin molded body 11 has a shape in which a plate having a predetermined thickness and a certain width is bent into a U-shape, and holes 11 a that are parallel to each other at the end surfaces thereof. Is provided.

In Embodiment 1, as shown in FIG. 2, the insert insert 1 includes a base portion 1 b, a convex portion 1 a that protrudes from the base portion 1 b and contacts the inner periphery of the U-shaped resin molded body 11, and a convex portion. And a pin 1c provided on the base portion 1b on both sides of 1a. The pin 1c has the same length as the depth of the hole 11a of the resin molded body 11 and is tapered (extracted taper: about 1 °, for example) so that the diameter becomes slightly smaller toward the tip. The cage (FIGS. 4A and 4B) facilitates removal from the resin molded body.
Thus, even when the resin molded body 11 is cooled and contracted, when the insert insert 1 is pulled out, it becomes easy to release with a small resistance, and the resin molded body 11 does not crack and does not generate warpage. It becomes possible to obtain a molded body. If the gradient is less than 1 degree, depending on the resin, the mold release resistance increases and the workability deteriorates.

  The insert insert 1 configured as described above is fixed in a cavity of a molding die 12 composed of a fixed die 12a and a movable die 12b. Specifically, as shown in FIG. 5, the movable mold 12b is formed with a recess in which the base portion 1b of the insert nest 1 just fits, and the insert nest 1 moves when the base portion 1b is fitted into the recess. The movable mold 12b is moved and clamped by being disposed at a predetermined position of the mold 12b. As a result, both ends of the base portion 1b located outside the pin 1c are sandwiched between the movable die 12b and the fixed die 12a, and the insert insert 1 is firmly fixed in the cavity of the molding die 12, A cavity for a resin molded body having a shape corresponding to the final product (resin molded body 11) is formed in the cavity of the molding die 12.

The fixed mold 12a is formed with a gate 12ag leading to the resin molded body cavity, and the molded resin is injected (injected) into the resin molded body cavity through the gate 12ag in a clamped state. .
It is preferable that the temperature of the insert insert 1 when the resin is injected into the cavity for the resin molded body is matched with the temperature of the molding die 12. As described above, when the temperature distribution of the mold is made uniform, the occurrence of warpage of the resin molded body due to the temperature distribution difference is suppressed, and the deformation of the resin molded body 11 can be more effectively suppressed.
Specifically, before placing the insert nest 1 in the cavity of the molding die 12, in a state where the insert nest 4 is preheated by 1 to 3 ° C. higher than the mold temperature when the resin is injected, The insert insert 1 is placed in the molding die. Thereby, transfer of heat when the insert insert 1 is inserted into the molding die is minimized, and the temperature distribution of the die can be made uniform.

  And after molding resin is inject | poured, the resin molding 11 is taken out from the shaping die 12 in the state united with the insert nest 1, and is hold | maintained with uniting until it cools to room temperature.

In the method for producing a resin molded body using the insert insert 1 according to Embodiment 1 described above, the shape is maintained by the insert insert 1 until it is cooled to room temperature even after being taken out from the mold, so that no deformation occurs. Molding becomes possible.
In particular, in the resin molded body 11 having the shape shown in FIG. 1, the resin molded body 11 is cooled in a state where the convex portion 1a of the insert insert 1 is inserted into the U-shaped inner periphery and the pin 1c is inserted into the hole 11a. Therefore, high accuracy of the diameter and interval of the holes 11a is ensured.

  Moreover, in this Embodiment 1, it is also possible to perform the gate cut of the resin molded body 11 in a state where it is combined with the insert insert 1, thereby preventing the resin molded body 11 from being damaged when performing the gate cut processing.

Modification 1
FIG. 6 is a perspective view (a) and a plan view (b) showing a configuration of a modified example of the insert insert 1 according to the first embodiment of the present invention.
The resin molded body 111 molded by this modification is configured in the same manner as the resin molded body 11 of the first embodiment except that the resin molded body 11 of the first embodiment has no holes 11a, and the insert inserts 101 are parallel to each other. The groove 101a is made of a substantially rectangular parallelepiped member formed on one main surface.
Each of the grooves 101a of the insert insert 101 has a shape corresponding to both ends of the resin molded body 111, and is one of the cavities for the resin molded body arranged at predetermined positions in the cavity of the molding die. Parts. After molding, the resin molded body 111 is taken out of the mold in the state shown in FIG. 6A, and then cooled to room temperature while the shape is held by the insert insert 101. Even if it does as mentioned above, shaping | molding without generation | occurrence | production of a deformation | transformation is attained.
In addition, it is preferable that the groove 101a of the insert nest 101 is formed with a drawing taper, whereby the resistance when the insert nest 101 is removed from the resin molded body 111 can be reduced, and workability can be improved.

Embodiment 2. FIG.
FIG. 7 is a perspective view schematically showing a mold structure in the method for producing a resin molded body according to Embodiment 2 of the present invention.
The manufacturing method of the resin molded body of Embodiment 2 is cooled to room temperature in a state where the shape is held by the shape holding portion 2 provided in the movable mold 22b-n without using an insert insert separable from the mold. It is what I did. In particular, in the second embodiment, the molded resin molded body is shaped and moved while being moved in the sliding direction sequentially using the movable molds 22b-n each having the shape holding part 2 and connected in a row. 2 is configured to cool to room temperature while maintaining the shape.
Here, in this specification, the part number n in the mobile type 22b-n is a natural number of 1 or more, and is used when the order is not particularly specified in a plurality of mobile types.

That is, in the second embodiment, a plurality of movable dies 22b-n (n is an integer of 2 or more) configured integrally with the shape holding portion 2 corresponding to the insert insert are arranged in a direction (sliding direction) orthogonal to the mold opening direction. Using the collective mold 22b arranged in parallel, the movable molds 22b-n are sequentially clamped to the fixed mold 22a to perform molding.
In this manner, the resin molded body that has been previously molded while the molding is repeated is cooled to room temperature.

  In the method of manufacturing a resin molded body using the collective mold 22b in which the movable molds 22b-n integrated with the shape holding unit 2 of the second embodiment are arranged, the mold is cooled to room temperature even after the mold is opened. Since the shape is held by the shape holding unit 2, it is possible to perform molding without causing deformation.

Embodiment 3. FIG.
The molding method according to the third embodiment of the present invention is a molding method using the insert insert 3 that prevents warping of the plate-shaped resin molded body 31.
That is, as shown in FIG. 8, the resin molded body 31 molded by the method of Embodiment 3 is a plate-like body having two opposing main surfaces and four side surfaces, and the insert insert 3 is a resin. The molded body 31 covers the entire outer surface of the other main surface so as to wind up two opposing side surfaces in close contact with the entire surface of one main surface.

The insert insert 3 configured as described above is fixed in a cavity of a molding die 32 including a fixed die 32a and a movable die 32b.
Specifically, as shown in FIGS. 9 and 10, the movable mold 32b is formed with a recess in which the insert nest 3 is accommodated, and the insert nest 3 is fitted into the recess so that the movable mold 32b is placed at a predetermined position. Arranged, the movable mold 32b is moved and clamped. As a result, the insert insert 3 is sandwiched between the movable die 32b and the fixed die 32a and is firmly fixed in the cavity of the molding die 12, and the final product (resin molding) is placed in the cavity of the molding die 32. A cavity for a resin molded body having a shape corresponding to the body 3) is formed.

The fixed mold 32a is formed with a gate 32ag leading to the resin molded body cavity, and the molded resin is injected (injected) into the resin molded body cavity through the gate 32ag in a clamped state. .
After the molding resin is injected, the resin molded body 31 is taken out of the molding die in a state of being combined with the insert insert 3, and is held in a combined state until it is cooled to room temperature.

  In the manufacturing method of the resin molded body of Embodiment 1 described above, since the shape is held by the insert insert 3 until it is cooled to room temperature even after being taken out from the mold, molding without deformation such as warpage is possible. become.

  Moreover, in this Embodiment 3, the gate cut of the resin molded object 31 can also be performed in the state united with the insert nest | insert 3 and, thereby, the damage of the resin molded object 31 can be prevented when performing a gate cut process.

Embodiment 4 FIG.
The molding method according to the fourth embodiment of the present invention is a molding method using the insert insert 4 that prevents deformation of the ring-shaped resin molded body 41 after molding.
That is, the resin molded body 41 molded by the method of Embodiment 4 has a ring shape and a circular cross section, as shown in FIG.
The insert insert 4 used when molding the ring-shaped resin molded body 41 is made of a pulley-shaped disk that is in close contact with the inner periphery of the resin molded body 41.
The insert insert 4 includes two insert inserts (first insert insert) 4a and an insert insert (second insert insert) 4b, and can be divided in the axial direction.

The insert insert 4 configured as described above is fixed in a cavity of a molding die 42 including a fixed die 42a and a movable die 42b.
Specifically, as shown in FIG. 12, the movable mold 42b and the fixed mold 42a are respectively formed with recesses in which the insert inserts 4 are accommodated, and the insert inserts 4 are arranged at predetermined positions on the movable mold 42b. Tightened. Thus, the insert insert 4 is sandwiched between the movable die 42b and the fixed die 42a and is firmly fixed in the cavity of the molding die 42, and the final product (resin molding) is placed in the cavity of the molding die 42. A cavity for a resin molded body having a shape corresponding to the body 41) is formed.

The fixed mold 42a is formed with a gate 42ag leading to the resin molded body cavity, and the molded resin is injected (injected) into the resin molded body cavity through the gate 42ag in a clamped state. .
After the molding resin is injected, the resin molded body 41 is taken out of the molding die in a state of being combined with the insert insert 4, and is held in a combined state until it is cooled to room temperature.

  In the method for producing a resin molded body according to the fourth embodiment, since the shape is held by the insert insert 4 until it is cooled to room temperature after being taken out from the mold, it is possible to perform molding without occurrence of deformation such as warpage. become.

  In the fourth embodiment, the gate cut of the resin molded body 41 can be performed in a state of being combined with the insert insert 4, thereby preventing the resin molded body 31 from being damaged when performing the gate cut processing.

1,3,4,101 insert nesting,
1b base part,
1a convex part,
1a convex portion 1c pin,
2 shape holding part 2,
4a first insert nesting,
4b second insert nesting,
11, 31, 41, 111 resin molded body,
11a hole,
12, 32, 42 Mold,
12a, 32a, 42a fixed type,
12b, 32b, 42b movable type,
12ag, 32ag gate,
22a fixed type,
22b collective type,
22b-n mobile type,
101a Groove.

Claims (11)

A method for producing a resin molded body in which a resin molded body is taken out after injecting resin into a cavity of a molding die,
A method for producing a resin molded body, comprising: cooling the mold while maintaining the shape of the resin molded body with a shape holding member constituting a part of the cavity shape after opening the molding die. The shape holding member is an insert insert that is detachably disposed with a resin molded body in a cavity of the molding die,
Placing the insert nest in the cavity of the mold,
The method for producing a resin molded body according to claim 1, further comprising taking out the resin molded body together with the insert insert and cooling the resin after injecting the resin into the cavity.   The manufacturing method of the resin molding of Claim 2 which makes the temperature of the said insert nest | insert when inject | pouring resin in the said cavity correspond with the temperature of a shaping die.   4. The method according to claim 2, further comprising preheating the insert nest before placing the insert nest in the cavity so that the insert nest is 1 to 3 ° C. higher than a mold temperature when the resin is injected. A method for producing a resin molded article. The shape holding member is formed integrally with the molding die,
The manufacturing method of the resin molding of Claim 1 which removes the said resin molding from the said shape holding member after cooling after the mold opening of the said shaping | molding die.   An insert insert which is detachably disposed with a resin molded body in a cavity of a molding die, and has a shape corresponding to a partial shape of the resin molded body.   The insert insert for molding according to claim 6, wherein the insert insert can be divided into two or more.   7. The insert insert for molding according to claim 6, wherein the partial shape includes a convex portion, and a punched taper is formed in a concave portion provided in the insert insert corresponding to at least a portion of the convex portion.   The resin molded body has a plate-like shape having two opposing main surfaces and side surfaces, and the insert insert covers two main surfaces facing one main surface, and further, from the side surfaces to the other main surface. The insert insert for molding according to claim 6, wherein the insert insert extends to cover a part of the outer periphery of the surface.   The molding insert insert according to claim 6, wherein the resin molded body has a ring shape, and the insert insert has a shape corresponding to an inner peripheral shape of the ring shape as an outer peripheral shape thereof.   The insert insert for molding according to claim 10, wherein the insert insert is formed so as to be split into two in the central axis direction of the ring shape.

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