JP4259676B2 - Injection mold - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an injection mold in an injection molding machine that moves a slide core for undercut processing, and in particular, realizes integral molding of electric / electronic parts and small mechanical parts, which are small part injection molded parts. Furthermore, the present invention relates to a technique for removing the obstacles to the metal member integrally molded with the resin molded product accompanying the slide core moving operation and improving the yield.
[0002]
[Prior art]
In a small resin injection molded product such as an electric / electronic component, a technique of insert molding a metal member for circuit formation is known. For example, in the case of a pickup that reads a compact disc (CD) or the like with a laser beam, the pickup includes an optical system composed of a light emitting element, a light receiving element, a mirror, and a lens, and a drive that drives these optical systems for focusing operation. The movable body block part to which the lens etc. is attached and the fixed side block part are made of resin molded products, and the movable side block and the fixed side block are movable with respect to the fixed side block. Are connected by elastic metal conductors which are mechanically held together and transmit electrical signals. A part of this metal member is insert-molded on both blocks.
[0003]
Conventionally, in order to perform injection molding of this type of resin molded product, it has been necessary to individually mold a plurality of resin molded product blocks with an injection molding die, or to make a hole in the integrally formed block. It was.
[0004]
Further, as shown in FIG. 14 (a), an upper mold (not shown) of a mold (lower mold) 11 is formed as an injection mold that insert-molds a thin metal member and requires an undercut process. A slide core 2 that can be freely inserted and removed is disposed on the mating surface of the metal plate, and a thin plate-like metal member 5 that is integrally formed with a resin molded product in a concave portion of a lower mold body (core) 15 set in a mold 11. Is inserted, and the slide core 2 is moved in the direction of arrow F through the rod 32 by the operation of the fluid pressure cylinder 31 to perform the closing operation.
[0005]
[Problems to be solved by the invention]
However, in the conventional mold as described above, in the case of individually molding the resin molded product blocks, the process becomes complicated, and the variation in the drilling process becomes large and the yield is not good. was there.
[0006]
Further, in the mold having the slide core 2 for undercut processing, as shown in FIG. 14B, there is a case where the metal member 5 is slightly curved and floats, or there is a press-unburring. If it exists, since the clearance between the slide core 2 is small, there is a problem that the metal member 5 is hooked at the tip of the slide core 2 and the metal member 5 and the slide core 2 are deformed / damaged. Further, if the clearance is increased in order to prevent the metal member 5 and the slide core 2 from being deformed / damaged, there is a problem that resin leaks from the gap between the mold and the metal member.
[0007]
The present invention solves the above-mentioned problem, and it is possible to insert-mold a metal member even for a complicated resin molded product by a simple molding process. An object of the present invention is to provide an injection mold that can be prevented from being hindered by being caught at the tip of a slide core for undercut processing to deform or break a metal member or the like.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the invention described in claim 1 is composed of an upper mold and a lower mold and a slide core for undercut processing, and in a space formed by these upper and lower molds and the slide core. In an injection mold in which a metal member is insert-molded by injecting resin while the metal member is inserted, the metal member is arranged in a plurality of rows at intervals in the vertical direction in at least two stages in the mold. In addition, the slide core is molded in a form straddling between a plurality of resin molded product blocks obtained by injection molding, and the slide core is inserted and removed from the lateral direction between the at least two metal parts in the vertical direction. both Once, the plurality of rows of metal members between the upper mold in, being like any of the lower mold or a slide core is inserted or removed from the transverse direction perpendicular to the direction or the vertical direction, Further, a holding mechanism that holds the slide core forward / backward and upward / downward with a predetermined clearance with respect to the lower mold, and forward / backward movement of the slide core for opening / closing operation. Drive means and raising means for raising the slide core are provided, and the slide core is moved forward by the drive means in a state where the slide core is raised by the raising means .
[0009]
In the above configuration, the metal members to be insert-molded are arranged in a plurality of rows at predetermined intervals in at least two steps in the mold, and the slide cores are inserted and removed from the horizontal direction within the predetermined intervals. Another slide core is inserted / removed from the direction orthogonal to the horizontal direction or the vertical direction. With such a configuration, a metal member can be integrally molded even with a complicated resin molded product by a simple molding process. Specifically, it is possible to easily obtain an insert molded product in a form in which a plurality of rows of metal members arranged between at least two steps in the vertical direction are straddled between resin molded product blocks divided into a plurality of parts obtained by injection molding. it can.
[0010]
Further, the moving direction of the slide core to be inserted / removed between the metal members arranged in a plurality of rows at intervals in the vertical direction in at least two steps in the mold is not limited to the lateral direction. There is also a direction orthogonal to the horizontal direction or a vertical direction. Further, the mold to be inserted and removed is not limited to the slide core, and may be an upper mold or a lower mold.
[0012]
Furthermore, the slide core is raised by the raising means, a predetermined clearance is formed between the metal member and the slide core, and the slide core is held while holding the predetermined clearance from the metal member with the slide core raised. When the slide core is moved forward and the closing operation of the slide core is completed, the lifting operation of the slide core is stopped and the slide core is lowered until it comes into contact with the metal member. By operating in this way , in addition to the above effects, the metal member will not be caught by the tip of the slide core, and the metal member will not be deformed or damaged by the tip of the slide core. The resin molded product can be produced and the yield is improved.
[0013]
According to a second aspect of the present invention, in the injection molding machine according to the second aspect, any one or more of mechanical means such as a fluid pressure cylinder, an electromagnetic actuator, or a cam is used as the raising means. In this configuration, the raising means is provided for each of the slide cores arranged corresponding to the multiple stages even when the metal members are stacked in multiple stages in the vertical direction.
[0014]
According to a third aspect of the invention, the injection mold according to claim 2, in a state where the lower metal member in the lower mold is set, the holding mechanism, the drive means and lifting means, said slide the core is moved with clearance on the upper surface of the metal member, at further wherein the slide core is moved downward direction perpendicular to the moving direction, a state in which the upper surface of the slide core upper metal member is set, the upper The mold is lowered to close the mold, and the resin is injected .
[0015]
In the above configuration, since the slide core is moved with a predetermined clearance in the state where the lower metal member is set in the lower mold, the metal member is hooked at the tip of the slide core. Disappears. The metal member is not deformed or damaged by hooking at the tip of the slide core, the yield is improved, and the metal member is inserted by simply setting the metal member on the upper surface of the stopped slide core. The 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]
DETAILED DESCRIPTION OF THE INVENTION
An injection mold according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram conceptually showing a basic form of a mold having a slide core of the present invention. The injection mold includes a lower mold 11, an upper mold 16 and a plurality of slide cores 2, and insert-molded metal members 5 a and 5 b are set at intervals in the vertical direction of two stages (set of the set). And the slide core 2 is inserted into and removed from the metal members 5a and 5b opposite to each other in the lateral direction (in the directions of arrows A and B). Then, it is inserted and removed in a direction orthogonal to this direction (directions of arrows C and D). By adopting such a mold configuration and operation, it is possible to manufacture a resin molded product in which a material having a certain distance between the plurality of metal members 5a and 5b is insert-molded.
[0017]
Fig.2 (a) is a perspective view of an example of the resin molded product by which injection molding is carried out in the form which a metal member straddles between the resin molded product blocks divided | segmented into plurality, FIG.2 (b) is II of Fig.2 (a). -It is an II line end view. 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. An upper metal member 5b is set on the upper surface of the slide core 2, the upper mold 16 is closed, and resin is injected. Thereafter, by opening the mold, it is possible to form a resin molded product in which the resin molded product blocks 6 and 7 divided into a plurality are elastically coupled with the wire 8 made of the metal members 5a and 5b.
[0018]
FIG. 3 is a view showing an example in which the metal members 5 of the insert-molded product are stacked and arranged in multiple stages at intervals in the vertical direction. FIG. 4 shows how the insert molded product is taken out by opening the slide core 2 and the upper mold 16 in three directions in a mold for resin molding the insert molded product having the arrangement as shown in FIG. 2 or FIG. .
[0019]
FIG. 5 is a diagram for explaining a series of operations of the slide core in the mold as shown in FIG. Here, a case is shown in which the slide core 2 is inserted from both the left and right sides when the metal member is positioned at a certain distance. With the lower metal member 5a set in the recess of the lower mold 11, the slide core 2 is lifted 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. 5A). When the closing operation of the slide core 2 is finished, the raising 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. 5 (b)) and stopped. An upper metal member 5b is set on the upper surface of the slide core 2 (FIG. 5C). When the upper mold (not shown) descends above, the mold closing operation is completed. By such an operation, the metal members 5a and 5b are not hooked at the distal end portion of the slide core 2, and the metal member 5 and the like are not deformed or damaged by the distal end portion of the slide core 2.
[0020]
When the metal member is set further upward, the upper slide core on the upper surface of the metal member 5b may repeat the same operation as described above.
[0021]
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 opened, FIG. 7 shows a state where the slide core is closed, 8 and 9 show a partial cross section of the mold. The lower mold 11 includes a mold mounting plate 11a, a spacer block 11b, a holder 11c, and a lower mold body 15. The lower mold body 15 is held by the holder 11c, and the holder 11c is mounted on the mold via the spacer block 11b. It is fixed to the plate 11a. The upper mold is not shown. The lower metal member 5a is inserted into a predetermined recess of the lower mold body 15 for resin molding. In the internal space surrounded by the spacer block 11b, an ejector mechanism for extruding the final resin molded product is provided. The ejector mechanism includes an ejector plate 14 and a guide shaft 13 that guides its movement, and an ejector pin (not shown) is attached to the ejector plate 14.
[0022]
The driving means 3 is a means for linearly moving the slide core 2 to open and close, and includes a fluid pressure cylinder 31, its rod 32, a coupler 33, and a coupler 34. The rod 32 of the fluid pressure cylinder 31 is coupled to the coupler 33 and Connected to the slide core 2 via a connector 34, the rod 32 is moved forward and backward by the supply of pressure oil to the fluid pressure cylinder 31 or the discharge of pressure oil from the fluid pressure cylinder 31, and the slide core 2 moves forward and backward. Let The fluid pressure cylinder 31 is fixed to the bracket 35. The drive means 3 includes various means such as a mechanical means such as a cam in addition to the fluid pressure cylinder 31 described above, and a structure that converts the rotational motion of a rotating device (for example, a motor) into a linear motion such as a rack and pinion mechanism. Can take.
[0023]
A slide presser (holding mechanism) 22 (FIGS. 8 and 9) for guiding the slide core 2 is made of a member having an L-shaped cross section and is arranged on the upper surface of the holder 11c so as to cover the slide core 2 having a convex cross section. The core 2 is held so as to be movable forward / backward and upward / downward with respect to the lower mold 11 to smoothly move the slide core 2 in a straight line. A predetermined clearance Y is formed in the height direction between the step surface 2 a of the slide core 2 and the step surface 22 a of the slide retainer 22.
[0024]
The raising means 4 for raising the slide core 2 is formed in the holder 11c, and a flow path for supplying a push-up piece 41 that pushes up the slide core 2 from below and a fluid pressure (air pressure) for pushing up the push-up piece 41. 46a, 46b, 47a, 47b, and the flow paths 46a, 46b, 47a, 47b are formed in the holder 11c and the spacer block 11b. A rod portion 42 that is directed downward is fixed to both ends of the push-up piece 41, the push-up piece 41 is inserted into a recess 44 formed on the surface of the holder 11c, and the rod portion 42 includes two vertical channels 47a, It is inserted into 47b so as to be movable up and down.
[0025]
The flow paths 46a, 46b, 47a, 47b include two vertical holes 47a, 47b for inserting the two rod portions 42 into the holder 11c and the spacer block 11b, and two for supplying fluid pressure from the outside. The horizontal holes 46a and 46b are formed. Plugs 48a and 48b are inserted and fixed to the side opening of the horizontal hole 46a and the lower opening of the vertical hole 47a, respectively, and fluid pressure such as air can be supplied from the opening 46c of the horizontal hole 46b to both the vertical hole 47a and the vertical hole 47b. It has a structure. When fluid pressure is supplied from the horizontal hole 46b, the rod portion 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 portion 42 descends.
[0026]
The 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 in the recess 44 of the holder 11c. The push-up part piece 41 is made of a convex member in cross section, and its protruding side protrudes 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 on the locking member 49, and when the slide core 2 is raised, the convex portion forming surface 41b of the push-up piece 41 contacts the horizontal wall 49d formed by the step of the locking member 49, and when the slide core 2 is lowered. A clearance X is generated between the horizontal wall 49d of the locking member 49 and the convex forming surface 41b of the push-up piece 41. This clearance X is a height at which the push-up piece 41 actually pushes up the slide core 2. The clearance Y described above is set to the clearance X, for example, clearance Y = X + 0.02 (mm). The reason why the clearance Y is set wider than the clearance X is to smoothly move the slide core 2 forward and backward.
[0027]
FIG. 10 shows an example of a molded product that is resin-molded by the mold of the present invention. Here, a state immediately after the molding of a pick-up resin molded product for an optical disc apparatus is shown, and FIG. The pick-up resin molded product is shown. In this resin molded product, two resin molded product blocks 6 and 7 are connected by a wire 8 of a plurality of metal members 5. One resin molded product block 6 is provided with an optical system including a light receiving element that receives laser light from a light projecting element through a lens and a mirror, and the other resin molded product block 7 is provided with these optical systems. A drive system composed of drive coils that drive in the tracking direction and the focus direction is provided for focusing operation, and the wire 8 of the plurality of metal members 5 elastically connects between the resin molded product blocks 6 and 7 and resin molded product. Electrical energy is supplied to both the optical system and the drive system through terminals 9 insert-molded in the blocks 6 and 7. FIG. 12 is a plan view of a state before the mold slide core is closed when molding such a resin molded product, and FIG. 13 is a side sectional view of the state where the slide core is closed. After the metal member 5a is set on the lower mold body 15, the slide core 2 is raised by the push-up piece 41 in the lower mold 11, and the slide core 2 is closed with a slight clearance on the upper surface of the metal member 5a. When the forward movement of the slide core 2 is completed, the core 15a and the metal member 5b are further set, the upper mold 16 is lowered from above, the upper mold 16 and the lower mold 11 are closed, and the resin is filled. inject.
[0028]
After a predetermined time required for resin solidification 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 placed inside the lower mold 11. The mold is released from the mold by pushing up with the ejector pin. As shown in FIG. 10, the resin molded product immediately after the release is such that the resin molded product blocks 6, 7 are elastically connected by a wire 8 that forms part of the metal member 5, and the resin molded product A plurality of terminals 9 are formed on the outer wall surfaces of the blocks 6 and 7 in a protruding manner. By cutting the runner 55, the resin molded product is completed as shown in FIG.
[0029]
The metal member is not limited to a material made of metal, but can be inserted into a mold for resin molding and can be integrally molded with a resin molded product, a component such as a printed circuit board, etc. It may be a metal fitting. The raising means 4 may be mechanical means such as a motor, a solenoid, and a cam in addition to the above-described fluid pressure.
[0030]
【The invention's effect】
As described above, according to the injection mold of the present invention, the metal members to be insert-molded are arranged in a plurality of rows at predetermined intervals in at least two stages in the vertical direction within the predetermined intervals. Since the slide core is inserted / removed from the horizontal direction, and the upper mold, the lower mold or the slide core is configured to be inserted / removed from the direction perpendicular to the horizontal direction or the vertical direction, a simple molding process Thus, the metal member can be integrally formed even for a complicated resin molded product. Moreover, since the molding process is simple, the resin molded product is of high quality and the yield is improved.
[0031]
Furthermore, according to the present invention, the slide core is raised during the closing operation of the slide core so that a predetermined clearance is provided between the metal member integrally formed with the resin molded product and the slide core, and the clearance is maintained. Because the slide core is moved forward, even if the metal member is curved and floating, or there is a press burr, the metal member etc. will not be hooked at the tip of the slide core and the metal member will not be deformed or damaged. , Can greatly contribute to the improvement of yield.
[Brief description of the drawings]
FIG. 1 is a perspective view conceptually showing the basic structure 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 insert molding in a form in which a metal member straddles between a plurality of divided resin molded product blocks obtained using the mold of the present invention; (B) is the II-II end view of (a).
FIG. 3 is a view showing an example in which insert-molded metal members are stacked and arranged in multiple stages at intervals in the vertical direction.
FIG. 4 is a view showing a movement of a mold when taking out a molded product in which metal members stacked in multiple stages are insert-molded.
FIGS. 5A, 5B, and 5C are views for explaining the movement of the slide core in the mold of the present invention.
FIG. 6 is a cross-sectional view showing a state in which a slide core according to a specific embodiment of the injection mold of the present invention is opened.
FIG. 7 is a cross-sectional view showing a state in which the slide core of the mold is closed.
8 is a cross-sectional view taken along line III-III in FIG.
9 is a partially enlarged view of FIG.
FIG. 10 is a perspective view immediately after completion of molding of a pickup resin molded product molded by the mold of the present invention.
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 mold, in which FIG. 14A is a side view before the slide core starts to move, and FIG. 14B is a side view showing a state where the slide core is moved and the metal member is deformed. FIG.
[Explanation of symbols]
2 Slide core 3 Driving means (for opening and closing the slide core)
4 Lifting means 5 for lifting the slide core 5 Metal member 5a Lower metal member 5b Upper metal member 6 Resin molded product block 7 Resin molded product block 8 Metal member wire 11 Lower mold 16 Upper mold

Claims (3)

It consists of an upper mold and a lower mold and a slide core for undercut treatment , and a metal is injected by injecting a resin with a metal member inserted into a space formed by these upper and lower molds and the slide core. In the injection mold for insert molding the member,
The metal members are formed in a form that is arranged in a plurality of rows at intervals of at least two stages in the vertical direction in the mold and straddles between the plurality of resin molded product blocks obtained by injection molding. Yes,
Wherein when the laterally slide core is inserted or removed between at least vertically two stages of the metal member together, either the transverse direction of the upper mold between a plurality of rows of metal member, the lower mold or a slide core Is inserted and removed from the direction orthogonal to or from the vertical direction ,
A holding mechanism for holding the slide core with a predetermined clearance with respect to the lower mold so that the slide core can move forward and backward, and move up and down;
Drive means for moving the slide core forward and backward for opening and closing operations;
A raising means for raising the slide core;
An injection mold, wherein the slide core is moved forward by the driving means in a state where the slide core is lifted by the lifting means . 2. The injection mold according to claim 1 , wherein the raising means uses at least one of a mechanical means such as a fluid pressure cylinder, an electromagnetic actuator, or a cam. In a state where the lower metal member is set in the lower mold, the holding mechanism, the driving unit, and the lifting unit move the slide core to the upper surface of the metal member with a clearance, and further move the slide core. moves downward direction perpendicular to the direction, the at top in a state where the upper metal member is set in the slide core, lowering the upper mold and closing the mold, and a resin is injected The injection mold according to claim 1 .

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