JP2001009845A - Mold for injection molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply perform insert molding of metal members even when a complicated resin molded article is to be molded, and to prevent faults which deform and break the metal members, etc. at apexes of slide cores when the slide cores are moved for closing for undercut processing from being generated. SOLUTION: Metal members 5a and 5b are arranged into a plurality of lines on at least two steps in up and down direction at definite intervals and slide cores 2 are pulled and inserted from a plurality of directions to simply perform insert molding of the metal members 5a and 5b and when the slide cores 2 are closed, they are forwarded under a condition where they are pushed up with pneumatic pressure (fluid pressure) to such a height where the metal members 5a are not caught by the apex parts of the slide cores 2, As the result, there exists no possibility of deforming and breaking the metal members 5a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection mold for an injection molding machine for moving a slide core for undercut processing, and more particularly to an electric / electronic part or a small mechanical part which is a small part injection molded article. To realize the integrated molding of
Further, the present invention relates to a technique for improving a yield by removing an obstacle on a metal member integrally formed with a resin molded product due to a slide core moving operation.

[0002]

2. Description of the Related Art For small-sized resin injection-molded articles such as electric and electronic parts, a technique of insert-molding a metal member for forming a circuit is known. For example, in the case of a pickup that reads a compact disk (CD) or the like with laser light, the pickup includes an optical system including a light emitting element, a light receiving element, a mirror, and a lens, and a drive that drives the optical system for a focusing operation. The movable block to which the lens and the like are attached and the fixed block are formed of a resin molded product, and the movable block and the fixed block are movable with respect to the fixed block. Are connected by an elastic metal conductor that mechanically retains and transmits electric signals. A part of this metal member is insert-molded in both blocks.

Conventionally, in order to perform injection molding of this type of resin molded product, a plurality of resin molded product blocks are individually molded by an injection molding die or holes are formed in an integrally formed block. Needed.

[0004] Further, as a metal mold for injection molding which requires insert molding of a thin plate-shaped metal member and requires an undercut treatment, as shown in FIG.
A slide core 2 which can be freely inserted and removed is arranged on a mating surface of an upper mold 1 (not shown), and is integrally formed with a resin molded product in a concave portion of a lower mold body (core) 15 set in a mold 11. It is known that a thin metal member 5 is inserted and the slide core 2 is moved in the direction of arrow F via a rod 32 by the operation of a fluid pressure cylinder 31 to perform a closing operation.

[0005]

However, in the case of individually molding resin molded product blocks in the conventional mold as described above, the process becomes complicated, and the variation in the perforation process is reduced. There has been a problem that the yield has become large and the yield is not good.

In a mold having a slide core 2 for undercut processing, as shown in FIG. 14B, when the metal member 5 is slightly curved and floats, If there is a burr or the like, the clearance between the slide core 2 and the slide member 2 is small.
However, there is a problem of causing deformation and breakage. Also,
If the clearance is increased in order to prevent the deformation and breakage of the metal member 5 and the slide core 2, there is a problem that resin leaks from the gap between the mold and the metal member.

The present invention solves the above-mentioned problems, and enables a simple molding process to insert-mold a metal member even for a complicated resin molded product, and is integrally molded with the resin molded product. An object of the present invention is to provide an injection molding die capable of preventing an obstacle such that a metal member is hooked on a leading end of a slide core for undercut processing to deform or break the metal member.

[0008]

In order to achieve the above object, the invention according to claim 1 comprises an upper die, a lower die, and a slide core for undercut processing, and insert molding a metal member. In the metal mold for injection molding, the metal member is arranged in a plurality of rows at intervals in at least two stages in the metal mold, and between a plurality of divided resin molded product blocks obtained by injection molding. It is formed in a straddling form, and a slide core is inserted and removed laterally between the at least two metal members in the vertical direction, and an upper mold, a lower mold or a slide is provided between the plurality of rows of metal members. One of the cores is inserted and removed from a direction perpendicular to the horizontal direction or a vertical direction.

In the above construction, a plurality of rows of metal members to be insert-molded are arranged in the mold at predetermined intervals in at least two stages in the vertical direction, and the slide core is inserted and removed from the horizontal direction within the predetermined interval. At the same time, another slide core is pulled out and inserted from a direction perpendicular to the horizontal direction or a vertical direction. With such a configuration, a metal member can be integrally formed by a simple molding process even for a complicated resin molded product.

Further, the moving direction of the slide core to be inserted and removed between the metal members arranged in a plurality of rows at least two steps vertically in the mold is limited to the horizontal direction. However, there is also a direction perpendicular to the horizontal direction or a vertical direction. Also, the mold to be inserted and removed is
The invention is not limited to the slide core, and may be an upper mold or a lower mold.

[0011] The invention according to claim 2 comprises an upper mold and a lower mold and a slide core for undercut processing.
In an injection molding die for insert molding, a holding mechanism for holding the slide core in a forward / backward movement and up / down movement with a predetermined clearance with respect to a lower mold, and for opening and closing the slide core. A driving means for moving the slide core forward and backward, and a raising means for raising the slide core, wherein the slide core is moved forward by the driving means in a state where the slide core is raised by the raising means. .

In the above construction, the slide core is raised by the lifting means, a predetermined clearance is formed between the metal member and the slide core, and a predetermined clearance is held from the metal member with the slide core raised. When the slide core is moved forward while the closing operation of the slide core is completed, the raising operation of the slide core is stopped and the slide core is lowered until it comes into contact with the metal member. By performing such an operation, the metal member is not caught by the tip of the slide core, and the metal member and the like are not deformed or damaged by the tip of the slide core, and a high-quality resin molded product is produced. And yield can be improved.

According to a third aspect of the present invention, in the injection molding machine of the second aspect, a fluid pressure cylinder,
It uses one or more of an electromagnetic actuator and mechanical means such as a cam. In this configuration, even when the metal members are stacked in multiple stages in the vertical direction, the lifting means are provided individually for the slide cores arranged corresponding to the multiple stages.

According to a fourth aspect of the present invention, in the metal mold for injection molding according to the second aspect, the metal member has at least two metal members.
The slide core is disposed on the upper surface of the metal member in a state where the lower metal member is set in the lower mold, and the slide core is arranged integrally with the resin molded product at intervals in the vertical direction of the step. The slide core is moved with a clearance, and then the slide core is moved in a downward direction orthogonal to the moving direction, and an upper metal member is set on the upper surface of the slide core.

In the above configuration, the slide core is moved with a predetermined clearance on the upper surface of the metal member in a state where the lower metal member is set in the lower mold.
The metal member does not get caught on the tip of the slide core. The deformation and breakage of the metal member etc. due to the hook at the tip of the slide core is eliminated, the yield is improved, and the metal member is inserted only by setting the metal member on the upper surface of the stopped slide core. A molded resin molded product can be obtained by a simple molding process. Furthermore, by alternately stacking the operation of the slide core and the set of metal members, a resin molded product obtained by insert-molding the metal members stacked in multiple stages can be obtained by a simple molding process.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An injection molding die according to one embodiment of the present invention will be described with reference to the drawings. FIG.
It is a figure which shows notionally the basic form of the metal mold | die which has the slide core of this invention. The injection mold includes a lower mold 11, an upper mold 16, and a plurality of slide cores 2, and metal members 5a and 5b to be insert-molded are set at two-step vertical intervals. The procedure and configuration for this will be described later in a specific example), and a plurality of slide cores 2 are inserted and removed from the metal members 5a and 5b so as to face each other from the left and right lateral directions (directions of arrows A and B). Are inserted and removed in a direction perpendicular to this direction (arrows C and D directions). By adopting such a mold configuration and operation, it is possible to manufacture a resin molded product obtained by insert molding a metal member having a certain distance between the plurality of metal members 5a and 5b.

FIG. 2A is a perspective view of an example of a resin molded product that is injection-molded so that a metal member straddles a plurality of divided resin molded product blocks, and FIG. 2B is a perspective view of FIG. 2) is an end view taken along line II-II. As shown in FIG. 1 above,
The lower metal member 5a is set in the lower mold 11, and the plurality of slide cores 2 are moved so as to be inserted into the space 5c above the metal member 5a. The member 5b is set, the upper mold 16 is closed, and the resin is injected. Thereafter, by opening the mold, it is possible to form a resin molded product in which the plurality of divided resin molded product blocks 6 and 7 are elastically connected with the wire 8 composed of the metal members 5a and 5b.

FIG. 3 is a diagram showing an example in which metal members 5 of an insert molded product are arranged in a multi-tiered manner at intervals in the vertical direction. FIG. 4 shows a mold for resin-molding an insert molded product having the arrangement shown in FIG. 2 or FIG.
The slide core 2 and the upper mold 16 are opened in three directions to take out an insert molded product.

FIG. 5 is a view for explaining a series of operations of the slide core in the mold as shown in FIG. Here, when the metal member is located at a certain distance,
The case where the slide core 2 is inserted from both right and left sides is shown. With the lower metal member 5a set in the recess of the lower mold 11, the slide core 2 is raised by lifting means (not shown) to form a predetermined clearance between the metal member 5a and the slide core 2. The slide core 2 is moved forward while maintaining this clearance (FIG. 5).
(A)). When the closing operation of the slide core 2 is completed, the lifting operation of the slide core 2 is stopped, and the slide core 2 is lowered until it comes into contact with the metal member 5a, and the metal member 5a is pressed down (FIG. 5B) and stopped. The upper metal member 5b is set on the upper surface of the slide core 2 (FIG. 5).
(C)). When the upper mold (not shown) descends above this, the closing operation of the mold is completed. By such an operation, the metal members 5a and 5b are not hooked on the distal end of the slide core 2, and the distal end of the slide core 2 does not deform or damage the metal member 5 or the like.

When the metal member is set further above, the upper slide core on the upper surface of the metal member 5b may repeat the same operation as described above.

6 to 9 are views showing a specific embodiment of the injection mold according to the present invention. FIG. 6 shows a state where the slide core is open, and FIG. 7 shows a state where the slide core is closed. 8 and 9 show partial cross sections of the mold. The lower mold 11 includes a mold mounting plate 11a, a spacer block 11
b, a holder 11c and a lower mold body 15, and the lower mold body 15 is held by the holder 11c.
Is fixed to the mold mounting plate 11a via the spacer block 11b. The upper mold is not shown. The lower metal member 5a is inserted into a predetermined concave portion of the lower mold body 15 for resin molding. An ejector mechanism for extruding a final resin molded product is provided in an internal space surrounded by the spacer block 11b. The ejector mechanism includes an ejector plate 14 and a guide shaft 13 for guiding its movement.
An ejector pin (not shown) is attached to the ejector plate 14.

The driving means 3 is a means for moving the slide core 2 linearly to open and close the slide core 2.
1. The rod 32 of the hydraulic cylinder 31 is connected to the slide core 2 via the coupler 33 and the connecting member 34 to supply the hydraulic oil to the hydraulic cylinder 31 or Fluid pressure cylinder 3
By the discharge of the pressurized oil from the rod 1, the rod 32 protrudes and retracts to move the slide core 2 forward and backward. Fluid pressure cylinder 3
1 is fixed to the bracket 35. This driving means 3
In addition to the fluid pressure cylinder 31 described above, various means such as a mechanical means such as a cam, and a structure for converting the rotational motion of a rotary device (for example, a motor) into a linear motion such as a rack and pinion mechanism can be adopted.

A slide holder (holding mechanism) 22 (FIGS. 8 and 9) for guiding the slide core 2 is formed of an L-shaped member in cross section, and is disposed on the upper surface of the holder 11c so as to cover the slide core 2 having a convex cross section. Then, the slide core 2 is held so as to be able to move forward and backward and move up and down with respect to the lower mold 11 so as to smoothly and linearly move the slide core 2. Step surface 2a of slide core 2 and slide holder 2
A predetermined clearance Y is formed in the height direction between the second step surface 22a and the second step surface 22a.

Lifting means 4 for raising slide core 2
Is formed in the holder 11c and includes a push-up portion 41 for pushing up the slide core 2 from below, and flow paths 46a, 46b, 47a, 47b for supplying fluid pressure (air pressure) for pushing up the push-up portion 41. Thus, the flow paths 46a, 46b, 47a, 47b are formed in the holder 11c and the spacer block 11b. A downwardly extending rod portion 42 is fixed to both ends of the push-up portion 41, and the push-up portion 41 is inserted into a concave portion 44 formed on the surface of the holder 11c.
7a and 47b are vertically movably inserted.

The flow paths 46a, 46b, 47a, 47b are
In the holder 11c and the spacer block 11b, two vertical holes 47a for inserting two rod portions 42,
47b and two horizontal holes 46a and 46b for supplying fluid pressure from outside. Horizontal hole 46a
Plugs 48a, 48 are provided in the side opening of
b is inserted and fixed, and the opening 46c of the horizontal hole 46b is fixed.
, Fluid pressure, for example, air can be supplied to both the vertical hole 47a and the vertical hole 47b. When the fluid pressure is supplied from the horizontal hole 46b, the rod 42 inserted into the vertical holes 47a and 47b rises. Thereby, the slide core 2 is pushed up. When the fluid pressure is discharged, the rod 4
2 descends.

A locking member 49 (FIGS. 8 and 9) for holding the push-up piece 41 is inserted and fixed together with the push-up piece 41 into the recess 44 of the holder 11c. The push-up portion 41 is formed of a member having a convex cross-section, and the projecting side thereof protrudes and retracts from the surface of the holder 11c to push up the lower surface of the slide core 2 and raise the slide core 2. A step is formed in the locking member 49, and when the slide core 2 is raised, the horizontal wall 49 formed by the step of the locking member 49 is formed.
When the slide core 2 is lowered, a clearance X is generated between the horizontal wall 49d of the locking member 49 and the protrusion forming surface 41b of the push-up piece 41 when the slide core 2 is lowered. . The clearance X is the height at which the push-up piece 41 actually pushes up the slide core 2. The clearance Y is set to be, for example, the clearance Y = X + 0.02 (mm) with respect to the clearance X. The reason why the clearance Y is made wider than the clearance X is to allow the slide core 2 to smoothly move forward and backward.

FIG. 10 shows an example of a molded article formed by resin molding using the mold of the present invention, and shows a state immediately after the completion of molding of a pickup resin molded article for an optical disk device.
FIG. 11 shows a pickup resin molded product obtained by cutting a runner of a metal member. This resin molded product is obtained by connecting two resin molded product blocks 6 and 7 by wires 8 of a plurality of metal members 5. One resin molded block 6 is provided with an optical system including a light receiving element for receiving laser light from a light emitting element via a lens and a mirror, and the other resin molded block 7 is provided with these optical systems. A drive system including a drive coil for driving in a tracking direction and a focus direction for a focusing operation is provided, and a plurality of wires 8 of the metal members 5 are provided.
Connects the resin molding blocks 6 and 7 elastically and supplies electric energy to both the optical system and the driving system through the terminal 9 inserted into the resin molding blocks 6 and 7. FIG. 12 is a plan view showing a state before the slide core of the mold is closed when molding such a resin molded product, and FIG. 13 is a side sectional view showing a state where the slide core is closed.
After the metal member 5a is set on the lower die body 15, the lower die 1
The slide core 2 is lifted by the push-up piece 41 in 1 and the slide core 2 is moved forward for closing operation with a slight clearance on the upper surface of the metal member 5a. The child 15a and the metal member 5b are set, the upper mold 16 is lowered from above, the upper mold 16 and the lower mold 11 are closed, and resin is injected.

After a predetermined time required for solidifying the resin has elapsed after injecting the resin, the upper mold 16 is opened, the slide core 2 is moved backward for the opening operation, and then the resin molded product is moved to the lower mold. The mold is released from the mold by pushing up with the ejector pin inside 11. As shown in FIG. 10, the resin molded products immediately after the release are molded with resin molded blocks 6 and 7.
Are elastically connected by a wire 8 forming a part of the metal member 5, and are formed with a plurality of terminals 9 protruding from the outer wall surfaces of the resin molded blocks 6 and 7. This resin molded product is completed by cutting the runner 55, as shown in FIG.

The metal member is not limited to a material made of metal, but may be a material that can be inserted into a resin molding die and can be integrally molded with a resin molded product, such as a printed circuit board. Parts and other fittings may be used. Also,
The lifting means 4 may use mechanical means such as a motor, a solenoid, or a cam, in addition to the above-described fluid pressure.

[0030]

As described above, according to the injection mold of the present invention, a plurality of insert-molded metal members are arranged in the mold at least two steps vertically at predetermined intervals. Since the slide core is inserted and removed from the horizontal direction within a predetermined interval, and the upper die, the lower die or the slide core is configured to be inserted and inserted from the direction orthogonal to the horizontal direction or the vertical direction. In addition, the metal member can be integrally formed with a complicated resin molded product by a simple molding process. Moreover, since the molding process is simple, the quality of the resin molded product is high, and the yield is improved.

Further, according to the present invention, the slide core is raised during the closing operation of the slide core to provide a predetermined clearance between the metal member integrally formed with the resin molded article and the slide core, and the clearance is increased. Since the slide core is moved forward while holding, even if the metal member is curved and floating or there is a press punch burr, the metal member or the like is hooked at the tip of the slide core, and the metal member or the like is deformed or damaged. And can greatly contribute to improving the yield.

[Brief description of the drawings]

FIG. 1 is a perspective view conceptually showing a basic configuration of an injection mold according to an embodiment of the present invention.

FIG. 2A is a perspective view showing an example of a resin molded product obtained by using the mold of the present invention and formed by insert molding in a form in which a metal member straddles a plurality of divided resin molded product blocks; (B) is an end view along line II-II of (a).

FIG. 3 is a diagram showing an example in which metal members to be insert-molded are stacked and arranged in multiple stages at intervals in the vertical direction.

FIG. 4 is a view showing the movement of a mold when removing a molded product obtained by insert-molding metal members stacked in multiple stages.

FIGS. 5 (a), (b) and (c) are views for explaining the movement of a slide core in the mold of the present invention.

FIG. 6 is a cross-sectional view showing a state in which a slide core is opened according to a specific embodiment of the injection molding die of the present invention.

FIG. 7 is a sectional view showing a state in which a slide core of the mold is closed.

FIG. 8 is a sectional view taken along line III-III of FIG. 6;

FIG. 9 is a partially enlarged view of FIG. 8;

FIG. 10 is a perspective view of a pickup resin molded product molded by the mold of the present invention immediately after completion of molding.

FIG. 11 is a perspective view of the pickup resin molded product.

FIG. 12 is a plan view of a slide core portion of a mold for molding the resin molded product.

FIG. 13 is a side sectional view of the slide core portion.

14A and 14B show a conventional injection molding die, and FIG. 14A is a side view before the slide core starts moving, and FIG. 14B is a side view showing a state where the slide core has moved and the metal member has been deformed. FIG.

[Explanation of symbols]

 2 Slide core 3 Driving means (for opening / closing operation of slide core) 4 Lifting means for raising slide core 5 Metal member 5a Lower metal member 5b Upper metal member 6 Resin molded block 7 Resin molded block 8 Wire rod of metal member 11 Lower mold 16 Upper mold

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shuichiro Koyama 3-20-16 Kamishinjo, Higashiyodogawa-ku, Osaka-shi F-term in Komatsu Light Works, Ltd. (reference) 4F202 AH33 AM32 CA11 CB01 CB12 CK32 CK54 CK84 CM02 CQ07 4F206 AH33 AM32 JA07 JB12 JQ81

Claims (4)

[Claims] 1. An injection molding die, comprising an upper die, a lower die, and a slide core for undercut processing, for insert-molding a metal member, wherein the metal member has at least two steps in the die. It is arranged in a plurality of rows at intervals in the vertical direction, and is formed so as to straddle between a plurality of divided resin molded product blocks obtained by injection molding. The slide core is inserted and removed from the lateral direction, and one of the upper mold, the lower mold and the slide core is inserted and removed between the plurality of rows of metal members in a direction orthogonal to the lateral direction or in a vertical direction. A mold for injection molding, characterized in that: 2. An injection mold for insert molding a metal member, comprising an upper mold, a lower mold, and a slide core for undercut processing, wherein the slide core is fixed to a lower mold relative to the lower mold. A holding mechanism for holding forward / backward movement and up / down movement freely with clearance, a driving unit for moving the slide core forward / backward for opening / closing operation, and a lifting unit for raising the slide core, An injection molding die, wherein the slide core is moved forward by the driving means while the slide core is raised by the lifting means. 3. The injection mold according to claim 2, wherein the lifting means uses at least one of a mechanical means such as a fluid pressure cylinder, an electromagnetic actuator, and a cam. 4. The metal member is disposed at least two steps vertically and is integrally formed with a resin molded product, and is provided in a state where the lower metal member is set in a lower mold. Then, the slide core is moved with a clearance to the upper surface of the metal member, and then the slide core is moved in a downward direction orthogonal to the moving direction. Further, the upper metal member is set on the upper surface of the slide core. 3. The injection mold according to claim 2, wherein: