JPH028567B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical field to which the invention pertains) The present invention relates to a mold device for resin molding of a disk-shaped information recording medium.

(Description of Prior Art) Information recording media, such as optical audio discs, computer discs, and video discs, having a hole in the center of the disc are manufactured using a resin molding mold device.

An explanation will be given below using an optical audio disk as an example. FIG. 1a is a plan view of an optical audio disk, and FIG. 1b is a sectional view.

The optical audio disc 1 has an aperture 2 in its center, and minute recorded information 3 is recorded in a spiral shape on one side, and the recorded information 3 is detected by irradiating laser beam light from the other side 4. configured to play.

The playback drive device rotates the audio disc 1 around the core of its opening hole 2, while
A laser pickup that irradiates laser beam light and detects reflected light is moved from the inner circumference to the outer circumference of the audio disk 1.

In order to keep the amount of information reproduced per unit time constant, the reproduction drive device automatically continuously reduces the rotational speed of the audio disk 1 and keeps the moving speed of the spiral track of the audio disk 1 with respect to the laser pickup constant. It's in control.

The pitch of this spiral track is 1.6 microns.
Information about the size of the pit: width 0.6 microns, depth
It is 0.4 microns in length and less than several microns in length, requiring high precision processing.

For this reason, the audio disk 1 as described above
The resin molding mold for molding must be designed so that the product satisfies the following requirements.

(a) The optical refractive index must be uniform.

Possible factors that cause non-uniformity in the distribution of photorefractive index include local non-uniformity in resin density, thermal stress applied during molding, and internal residual stress due to mechanical distortion.

As mentioned above, the laser pick-up uses a reading laser beam that enters from one side of the audio disk 1 and detects the reflected light from the other side. Therefore, if the optical refraction index is non-uniform, the recorded information cannot be read. becomes unreadable.

In order to uniformly fill the cavity of the mold with resin density, it is appropriate to uniformly emit the resin from the center of the disk in the diametrical direction. However, even with this method, the molding pressure tends to increase more easily at the outer circumference than at the inside of the cavity than on average, so it is necessary to appropriately set molding conditions.

In addition, when high-temperature molten resin material is injected into a low-temperature mold, intermittent thermal stress causes deformation of the mold due to dimensional expansion and contraction, and damage caused when the cavity is filled with resin material. Since there is a possibility that the mold may be warped due to pressure, sufficient countermeasures must be taken at the time of mold design.

(b) The thickness of the disk must be uniform. If the thickness of the disk is not uniform, the reading point of the reflected light will shift by twice the thickness error, just as in the case of a non-uniform optical refractive index, and the recorded information will be lost. It becomes difficult to read accurately.

Factors that affect the thickness include uneven density of the resin filled in the cavity and uneven cooling, as well as mold deformation due to expansion and contraction of the mold due to thermal stress, and flatness due to lack of rigidity. Deflection may occur, and sufficient countermeasures must be taken when designing the mold.

(c) The eccentricity between the spiral track and the central aperture and the aperture accuracy are maintained accurately.As mentioned above, audio disk reading is performed by a laser pick-up with the aperture center of the disk as the center of rotation.

Therefore, if there is eccentricity between the spiral track and the aperture and the aperture accuracy is poor, accurate reading will not be possible. Therefore, this requirement must be met without fail, and it is an extremely difficult requirement. For this purpose, the runner part 5 and the audio disk part 1 are integrally molded as shown in FIG. A method of separating one part has been proposed.

An example of a conventional mold apparatus for resin injection molding of such a disc-shaped recording medium is shown in FIG.

A portion a in the left half of FIG. 3 is a longitudinal sectional view showing a state in which injection filling is completed, and a portion b in the right half is a longitudinal sectional view showing a state in which opening hole cutting is completed.

This mold device is considered to be roughly divided into five groups of members.

The first group of fixed side mounting plates 7 are attached to the injection molding machine fixing platen 6 with bolts or the like.

A spool bush 9 having a runner hole 8 is fixedly attached to the center of the fixed side mounting plate 7. Four counterbore through holes 10 are provided so as to surround this spool bush 9.

The four guide posts 11 are attached to this fixed side mounting plate 7.
installed on. These fixed side mounting plates 7,
The pool bush 9 forms a first group of mold members.

A through hole 12 into which the spool bush 9 fits is provided in the center of the second group of fixed molds 15.

A tapered counterbore hole 13 is provided concentrically with the through hole 12 of the fixed mold 15, and the fixed mold body 14 is press-fitted into the tapered counterbore hole 13 into an integral structure with bolts. There is.

The fixed mold 15 is provided with four guide bushes 16 into which the guide posts 11 are fitted, and four through holes 19 for punch stop rods 18.

Four stopper rods 17 for regulating the amount of movement associated with the first group of counterbore through holes 10 are fixed to the upper surface of the fixed mold 15.

Fixed side latching members 20 such as pins constituting a part of a latching device are provided at two locations on the outer surface of the fixed mold 15.
A group is formed.

The third group of movable molds 25 has a punch 21 in the center.
A tapered counterbore hole 23 is provided concentrically with a through hole 22 that fits into the through hole 22 .

The movable mold body 24 is press-fitted into the taper counterbore hole 23 of the movable mold 25 with bolts and has an integral structure.

The movable mold 25 is provided with four guide bushes 26 into which the first group of guide posts 11 are fitted and through holes 27 for four punch stop rods 18.

Furthermore, movable latch members 28 are provided at two locations on the outer surface of the movable mold 25, forming part of a latch device and engaging with the fixed latch member 20 of the fixed mold.

The movable side mounting plate 30 is attached to the injection molding machine movable platen 29 with bolts or the like, and is provided with a stepped through hole 5 in the center. This movable side mounting plate 30 has a plurality of hydraulic and pneumatic cylinders 33 having an upper port 31 and a lower port 32, and the same number of piston rods 3.
A punch drive device with 4 fitted is provided. The movable side mounting plate 30 has a pair of left and right spacers 3.
6 and integrally connected to the movable mold 25 to form a third group of mold members.

The fourth group is constructed around a punch mounting plate 38 that is incorporated into a space 37 formed by the mold members of the third group.

Attach the ejector pin 3 to the center of the punch mounting plate 38.
A through hole 40 for 9 is provided.

The punch 21 and four punch stopper rods 18 are fixedly attached to the punch mounting plate 38 at the positions shown in the figure, and the upper end of a piston rod 34 is fixed to the lower surface thereof, and is connected to a third group of punch driving devices. .

The fifth group is composed of an ejector pin 39 that slidably fits into the center hole of the punch 21 and has a flange portion serving as a spring seat at the lower end, and a coil compression spring 41.

The operation of the recording medium injection molding mold configured as described above will be briefly described.

In FIG. 3a, the mold is clamped between the fixed platens 6 by applying mold clamping pressure P to the movable platen 29 in the direction of the arrow.

In this mold-clamped state, a nozzle 43 having an injection hole 42 in the center of the molding machine is moved forward and brought into close contact with the end face of the spool bush 9 under pressure.

The punch stopper rod 18 fixed to the punch mounting plate 38 that supports the punch 21 is attached to the mounting plate 7.
A space 37 is formed on the upper surface of the movable mounting plate 30 by being pressed against the lower surface of the movable mounting plate 30 .

The ejector pin 39 is placed at the bottom dead center position by the compression coil spring 41. Latch members 20, 28
are integrally engaged and locked.

In this state, the heated molten resin material is radially injected and filled into the cavity from the nozzle hole 42 through the runner hole 8 to form the original shape 1 of the audio disk.

As shown in FIG. 3b, when the mold clamping force P is released and the movable platen 29 is pulled in the direction of the arrow, the mold opening is started. However, at this time, in order to prevent the cavity surface of the punch 21 from moving, pressurized oil is forced to flow into the hydraulic/pneumatic cylinder 33 from the lower port 32 to push up the piston rod 34.

The fixed mold 15 is integrally engaged and locked with the movable mold 25 by latch members 20 and 28, so when the mold is opened, the fixed mold 15 and the movable mold 25 release the original form 1 of the audio disk molded between them. It is pulled downward while still being sandwiched.

At this time, the inner peripheral edge portion 44 of the movable mold body 14
serves as a knife to cut the opening.

Next, when the fixed side mounting plate 7 and the fixed mold 15 are opened by S, the flange portion of the stopper rod 17 comes into contact with the stepped portion of the stepped hole 10 and stops.

Note that it is sufficient for the dimension of S to be 2 to 3 mm. At the same time, the latch members 20, 28 are momentarily unlocked by a release device (not shown) and
From this point onward, only the movable side molds of the third group and below are moved downward. Thereby, although the procedure is omitted, the recording body 1 and the runner portion 8 can be taken out from the mold.

The ejector rod 46 is a drive rod built into the injection molding machine for ejecting the ejector pin 39.

Each mold body 14, 24 is provided with a spiral groove 47 for the mold body cooling water.

In the conventional mold device having the above configuration, the movable mold body 24 is assembled to the movable mold plate 25 by being press-fitted into the taper counterbore hole 23 as described above.

This is because if the punch 21 does not fit smoothly into the central hole edge 44 of the fixed mold body 14 with a fitting gap of 5 to 6 microns, it will not be possible to cut the opening hole. It depends on the reason why matching is required.

For this purpose, the fixed mold 14 and the movable mold 24 are
Each guide bushing hole and tapered counterbore hole must be precisely machined by simultaneous setup machining.

Transparent polycarbonate or the like is used as the resin material used to form such an audio disc prototype.

Transparent polycarbonate resin has an injection temperature of approximately 300
The material is injected into the cavity of a mold heated to about 80°C under an injection pressure of 1500 to 2000 kg/cm ² . At this time, the cavity surface of the mold instantly rises to 300℃, and the 46 cooling grooves provided on each opposite surface
It has a temperature gradient of 220°C, but the average temperature gradient is expected to be about 100°C, which is about half that.

Further explanation will be given using a mold for an optical video disc with a diameter of 30 cm as an example.

The outer diameter of the mold body is approximately 40cm, and the linear expansion coefficient is 12×
10 ^-6 , a temperature gradient of 100°C will cause the mold body to expand diametrically by approximately 0.48 mm on the cavity surface side. However, since the molds are press-fitted with tapered surfaces, the mold body deforms into a spherical shape with a raised center, as shown in FIG. 4, based on the outer diameter.

This deformation height Δt is calculated to be approximately 0.52 mm. Even if the effective recording width of a video disc is 10cm,
It becomes 0.26mm.

In Fig. 4, D is the outside diameter of the mold body 40 cm, d is the cavity diameter 30 cm, t is the mold thickness 4 cm, and p is the filling pressure inside the cavity.

Calculating the filling pressure p in the cavity required to return the spherically deformed mold to its original flat surface is approximately
It becomes 290Kg/ ^cm2 .

If we estimate the manner in which the pressure of the resin in the cavity fluctuates, the pressure will be low at the beginning when the entire cavity is filled, but the temperature of the cavity surface of the mold will suddenly rise as it comes into contact with the high-temperature molten resin. Causes spherical deformation. Thereafter, the average pressure of the resin in the cavity is maintained at about 300 to 350 kg/cm ² , and the resin is gradually cooled and solidified from the surface layer while increasing the packing density. During this period, the pressure in the cavity is maintained as a holding pressure, and the resin solidifies from the outer periphery of the cavity. Due to the initial spherical deformation of the mold, the resin is filled into a concave lens shape, and as the pressing force increases, the mold returns to its original state. Since it is restored to a flat surface, the resin density at the outer peripheral portion tends to be high, and it can be said that the mold structure promotes non-uniformity in optical refractive index and non-uniformity in thickness.

The mold is heated rapidly in the thin part of the surface layer, and the actual spherical deformation amount Δt may be much smaller than the calculated value, but this is a record that requires performance in the minute dimension of microns. It cannot be said that this mold is sufficient as a mold for manufacturing media.

Next, as shown in FIG. 3, in the conventional mold structure, the movable mold 25 has a pair of plate-shaped spacers 36 at both ends.
It has come to be supported by As shown in Figure 4, when calculating the opposite side dimension B of the movable mold as 55 cm, the support width L of the spacer as 45 cm, and the average injection pressure p applied to the cavity as 300 kg/cm ² evenly distributed load, the plate thickness T is assumed to be 20 cm. Even so, the maximum deflection at the center is 0.052
reaching mm.

The maximum deflection at the center is 0.023 mm even if the effective recording width of the video disc is 10 cm. in this case,
Since the resin is filled in a convex lens shape and returns to its original state when the forming pressure is removed, the resin density at the inner circumference tends to be higher than at the outer circumference. This seems to be advantageous in balance with the increase in density at the outer periphery due to the spherical deformation of the mold due to thermal stress, but it is difficult to mold a high-precision recording medium unless the mold dimensions remain unchanged under any conditions. It is.

(Description of the purpose of the invention) The purpose of the present invention is to solve the various defects of the conventional mold described above from the following viewpoints (a), (b), and (c), and to mold higher quality information recording media. Our goal is to provide mold equipment that can.

(b) Significant reduction in spherical distortion stress caused by expansion and contraction of the mold due to the amount of heat brought in by the heated molten resin (b) Elimination of plane deflection of the mold due to the pressure of the filling resin in the cavity (c) Simplification of the mold structure (Description of structure and function) In order to achieve the above object, the fixed side mold assembly of the resin molding mold device according to the present invention consists of a fixed mold mounting plate having a through hole in the center and a fixed mold body. The movable side mold assembly consists of a fixed side mold, a spool bushing having a runner hole in the center and biased toward the cavity space and slidably fitted into the through hole. a movable side mold consisting of a movable mold mounting plate having a through hole of the same shape as the mold and a movable mold body; a punch supporting an ejector pin in the center and slidably fitting into the through hole; The mold is supported so that the center of the through hole coincides with the center of the through hole of the stationary mold.

The axis alignment reference part includes a small diameter tapered cylindrical protrusion concentrically with the center axis of the mold body on the opposite side of the cavity surface of each of the mold bodies, and a taper cylindrical projection part of a small diameter provided on each of the mold mounting plates. It consists of a pilot hole that fits into the taper, and each of the mold bodies is fitted into and attached to it.

A mold driving device connects and tightens the movable mold assembly to the stationary mold assembly.

The punch driving device forcibly drives the punch. Then, while the mold is being clamped and fixed by the mold drive member, a heated molten resin is injected and filled into the cavity space formed by the molds, spool bush, punch, and ejector pin through the film gate from the runner hole of the spool bush; With the mold clamped and fixed, the spool bush, the punch, and the cooled solidified resin portion sandwiched between them are driven by the punch drive device so that the punch end face is partially inserted into the through hole provided in the fixed mold body. It is configured to move the molded product until it reaches the desired position and drill a hole in the molded product.

Further, the punch driving device that drives the punch is
The hydraulic device is composed of a piston rod and a cylindrical hydraulic cylinder, which has an ejector pin through hole in the center, a punch is integrally mounted using the punch attachment means on the upper end surface, and an ejector pin return spring seat is provided at the lower end. Can be done.

Further, a stepped cylindrical through hole for mounting the hydraulic cylinder from below can be provided in the center of the movable mold mounting plate, coaxially with the pilot hole.

According to the above configuration, the object of the present invention can be completely achieved.

(Description of Examples) The present invention will be described in more detail below with reference to the drawings and the like.

FIG. 5 is a longitudinal sectional view showing an embodiment of the mold apparatus according to the present invention.

In each figure, the same numerals are given to parts that are common to the conventional device described above in connection with FIG. 3.

Part a on the left side of the figure shows a state in which resin has been injected and filled into the cavity, and part b on the right side of the figure shows a state in which the opening hole shearing process has been completed.

The mold device according to this embodiment is composed of four groups of members.

The fixed mold main body 53 included in the first group is provided with a spool bushing through hole 50 in the center, and a disk protrusion 51 with a tapered side surface is provided concentrically with the spool bushing through hole 50. ing.

Further, the fixed mold main body 53 is provided with a plurality of counterbore holes 52 for bolts on the outer periphery of the disk protrusion 51. A stepped through hole 56 having a taper surface 54 that engages with the taper of the disk protrusion 51 of the fixed mold body 53 and a counterbore 55 on each end face is provided in the center of the fixed mold mounting plate 58. , four guide posts 57 are fixedly attached to the peripheral edge. The fixed mold main body 53 is integrally mounted with a plurality of stepped bolts 59 or the like so as to be slidably displaced by expansion and contraction in the diametrical direction with respect to the central tapered surface 54 of the fixed mold mounting plate 58.

The second group is formed around the spool bush 63.

The spool bush 63 has a runner hole 6 in the center.
0. A flange portion 61 serving as a spring seat is provided at the center of the outer periphery, and the lower portion of the outer periphery is fitted into the through hole 50 at the center of the fixed mold body 53 of the first group.

A ring-shaped spring washer 64 having an opening hole in the center for guiding the spool bush 63 is attached to the counterbore hole 55 of the fixed mold mounting plate 58 of the first group with bolts or the like.

A compression coil spring 62 is installed between the lower end surface of the ring-shaped spring washer 64 and the flange portion 61 of the spool bushing 63, and the lower surface of the flange 61 of the spool bushing 63 is connected to the step of the stepped through hole 56 of the first group. The lower end surface position of the spool bushing 63 is regulated by contacting the lower end surface of the spool bushing 63.

The movable mold body 67 included in the third group has a punch through hole 65 in the center and a tapered side surface concentric with the punch through hole 65, similar to the structure of the fixed mold body 53 in the first group. A plurality of counterbore holes 52 for bolts are provided on the outer periphery of the disk protrusion 66 .

The movable mold mounting plate 71 is provided at its center with a surface 68 that engages with the taper of the disk protrusion 66, a stepped through hole 69 consisting of two stages, and four guide bushes 70. Like the first group, the movable mold main body 67 is integrally attached to the movable mold mounting plate 71 using stepped bolts so as to be slidably displaced in the diametrical direction by expansion and contraction.

The fourth group includes a punch 75, a punch driving device, an ejector pin 81, an ejector pin return device, and an ejector rod 46.

The punch drive device includes a hydraulic cylinder 74, a piston rod 78, and a ring-shaped lid member 79. A hydraulic cylinder 74 having upper and lower ports 72 and 73 has a punch 75 attached to the upper part and a piston rod 78 having a counterbore hole 76 for an ejector pin return spring and a through hole 77 slidably inserted in the lower part. .

A ring-shaped cover member 79 having an opening in the center for guiding a piston rod 78 is fixedly attached to the lower surface of the hydraulic cylinder 74. A ring-shaped member 83 having an opening in the center through which the ejector rod 46 of the injection molding machine passes is fixedly attached to the lid member 79 with bolts or the like.

An ejector pin 81 having a flange portion is inserted from below the piston rod 78 and is slidably fitted into a through hole 82 of the punch 75.

Spring counterbore hole 76 at the bottom of the piston rod 78
A compression coil spring 80 serving as an ejector pin return device is inserted into the ejector pin 81 , and the lower end of the coil spring 80 is received by the flange portion of the ejector pin 81 .

The ejector pin 81 is urged downward by the compression coil spring 80 and pressed against the ring-shaped member 83 to determine the lower limit position.

The operation of the embodiment device configured as described above is as follows.

As shown in FIG. 5A, a mold clamping pressure P is applied to the movable platen 29, and the mold is sandwiched between the movable platen 29 and the fixed platen 6 to form a clamped state.

In this state, the nozzle 4 with the injection hole 42 in the center
At this time, apply sufficient pressure to the nozzle 43 so that the spool bush 63 is not pushed back due to the average filling pressure applied to the cross-sectional area of the spool bush 63 during resin injection. I need to add it.

At this time, the punch 75 is in the position shown because the piston rod 78 is at the bottom dead center in the hydraulic cylinder 74. Further, the ejector pin 81 is also at the bottom dead center, and the upper end surfaces of the punch 75 and the ejector pin 81 each form one surface of the cavity.

In this state, the heated molten resin material is radially injected and filled into the cavity from the nozzle hole 42 through the runner hole 60 to form the recording medium 1.

Part b on the right side of FIG. 6 shows the state where the opening hole shearing process is completed, and the mold clamping force P is never released until the shearing process is completely completed.

When the nozzle 43 is moved backward while the mold clamping force P is maintained, the spool bush 63 receives only the spring pressure of the compression spring 62 and initially remains stationary at the position shown in FIG. 6a.

By pressurizing appropriate pressure oil from the lower port 73 of the hydraulic cylinder 74, the piston rod 78
is raised to raise the punch 75 that is integrated with it.

The punch 75, the spool bush 63, and the resin part sandwiched between them are driven upward while eliminating the spring pressure of the spool bush 63, so that the upper end surface of the punch reaches the fixed mold body through hole 5.
The inner peripheral edge portion 84 of 0 is reached and the shearing process of the opening hole is completed.

After completing this shearing process, the mold clamping force is released.

(Effects of the Invention) Since the mold device according to the present invention is constructed and operates as described above, it has many advantages as described below.

First, each mold body is freely supported in alignment with a mold mounting plate by a small circumferential taper in the center.

Therefore, even though it is impossible to prevent spherical deformation due to the rise in temperature of the surface layer due to resin contact with the mold at the initial stage when heated molten resin fills the cavity, the outer peripheral surface of the mold body is Unlike the support method, it can be expanded and contracted freely.

If the amount of spherical deformation is the same as the conventional mold, and Δt is 0.52 mm in the thickness direction, the resin filling pressure in the cavity required to restore the spherically deformed mold to its original plane is calculated. It was found that it was only 28Kg/cm ² , which is about one-tenth of the 290Kg/cm ² .

As mentioned above, the average filling pressure in the cavity of polycarbonate resin is 300 to 350 Kg/cm ² , but even in the initial state of filling and diffusion, the pressure is over 100 Kg/cm ² . When using this method, the resin is filled in an almost flat surface rather than in the concave lens shape of the conventional method, so as the temperature of the mold decreases, the density in the peripheral area increases, greatly reducing the unevenness of the optical refractive index and thickness. Next, as is clear from the mold structure of an embodiment of the present invention shown in FIG. Since the structure has one round opening in the center of the thick plate, there is no uneven deflection except for the opening hole of the recording medium, and the recording medium is only subjected to uniform elastic compression over the entire surface. The impact is zero.

Therefore, the birefringence of the signal recording surface of an audio disk having a diameter of 12 cm molded by the mold according to the present invention can stably obtain an excellent value within 10 nanometers. Compared to the conventional mold, which was limited to achieving a birefringence of several tens of nanometers under the same injection molding conditions, this represents a significant performance improvement, making it possible to inject information storage disks for computers. We were able to increase the possibility of molding.

Furthermore, the mold according to the present invention can reduce the number of mold members to the utmost. In particular, the punch and ejector pin, which are frequently inspected and maintained, are integrally constructed with the hydraulic cylinder block, so they can be easily attached to and removed from the movable mold plate as a unit, and maintenance can be done without disassembling everything like conventional molds. At the same time, the defects that cannot be solved can be solved.

[Brief explanation of drawings]

FIG. 1a is a plan view of the audio disk, and FIG. 1b is a sectional view of the audio disk.
FIG. 2a is a cross-sectional view of the original audio disk with an unnecessary part molded from the runner part, and FIG. 2b is a cross-sectional view of the unnecessary part cut off and a central opening hole machined. FIG. 3 is a longitudinal cross-sectional view showing an example of the configuration of a conventional mold device for molding a disk-shaped recording medium, and part a of the figure shows the resin injection state;
Part b of the figure shows the sheared state of the opening hole. Fourth
The figure is a schematic sectional view for explaining the deformed state of a conventional mold. FIG. 5 is a vertical cross-sectional view showing an embodiment of the mold apparatus according to the present invention, in which part a shows the resin injection state, and part b shows the state after the shearing of the opening hole has been completed. It shows. 7...Fixed side mounting plate, 8...Runner hole, 9...
...Spool bush, 10...Counterbore through hole, 1
1...Guide post, 12...Through hole, 13...
Tapered counterbore hole, 15...Fixed mold, 16...Guide bush, 18...Punch stopper rod,
20... fixed side latch member, 23... taper counterbore hole, 24... movable mold body, 25... movable mold,
26...Guide bush, 27...Through hole, 28
...Movable side latch member, 29...Platin, 30...
...Movable side mounting plate, 31, 32...Port, 33...
... Cylinder, 36 ... Spacer, 38 ... Punch mounting plate, 39 ... Ejector pin, 41 ... Coil compression spring, 50 ... Through hole for spool bush, 51 ... Disk projection, 52 ... For bolt Counterbore hole, 53...fixed mold body, 54...tapered surface,
55... Counterbore hole, 56... Stepped through hole, 57...
...Guide post, 58...Fixed mold mounting plate, 59
...Stepped bolt, 60...Runner hole, 61...
Flange portion, 63...Spool bushing, 64...
...Spring washer, 65...Through hole for punch, 66...
Disc protrusion, 70... Guide bush, 71... Movable mold mounting plate, 74... Hydraulic cylinder, 75...
Punch, 76... Counterbore hole for ejector pin return spring, 78... Piston rod, 79... Lid member, 80... Compression coil spring, 81... Ejector pin, 82... Through hole.

Claims (1)

[Scope of Claims] 1. A fixed side mold consisting of a fixed mold mounting plate with a through hole in the center and a fixed mold main body, which has a runner hole in the center and is biased toward the cavity space and slides into the through hole. A fixed side mold assembly consisting of a spool bush that is movably fitted, and a movable side consisting of a movable mold mounting plate having a through hole of the same shape as the fixed side mold and a movable mold body. a mold, a punch that supports an ejector pin in the center and is slidably fitted into the through hole, and is supported so that the center of the through hole coincides with the center of the through hole of the stationary mold. a movable mold assembly, a small diameter tapered cylindrical protrusion concentric with the central axis of the mold body on the opposite side of the cavity surface of each of the mold bodies, and a tapered cylindrical projection part of a small diameter provided on each of the mold mounting plates. an axial center alignment reference part for fitting and attaching each of the mold bodies, which is formed of a pilot hole that fits into a taper, and a mold drive device that connects and tightens the movable mold assembly to the stationary mold assembly; A punch driving device forcibly drives the punch, and a film gate is inserted into the cavity space formed by the molds, spool bush, punch, and ejector pin from the runner hole of the spool bush while the mold is clamped and fixed by the mold drive member. The heated molten resin is injected and filled through the mold, and while the mold is clamped and fixed, the spool bush, the punch, and the cooled solidified resin part sandwiched between them are driven by the punch drive device and the punch end face is mounted on the mold body on the fixed side. A mold device for resin molding is configured to move the mold device until it is partially inserted into the through hole to punch a hole in the molded product. 2. The punch driving device for driving the punch includes a piston rod having an ejector pin through hole in the center, a punch mounting means on the upper end face to which the punch is integrally attached, and a piston rod having an ejector pin return spring seat on the lower end face, and a cylindrical hydraulic The mold device for resin molding according to claim 1, which is a hydraulic device composed of a cylinder. 3. According to claim 1, the movable mold mounting plate is provided with a cylindrical stepped through hole in the center thereof, coaxial with the pilot hole, for mounting the hydraulic cylinder from below. mold equipment for resin molding.