JPH0970831A - Mold equipped with guide pin for adjusting centering - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold equipped with a partition-integration type guide pin for adjusting centering in which the structure of a guide pin is improved to facilitate the adjustment of mold centering. SOLUTION: In a mold 11 equipped with a guide pin for adjusting centering, the guide pin 4 and a guide bush 5 have taper parts 12 which contact each other, and the guide pin 4 is separated into a pin front part 10 having a taper part 12 and a pin rear part 20 having a seat part 21 for polishing on the front and is composed of a partitioned guide pin in which a fixture 15 is screwed to a tapped hole 13 formed in the pin front part 10 through a central hole 22 penetrating the pin rear part 20. The contact of the taper part 12 is adjusted by polishing the seat part 21 to adjust the centering of a fixed side mold 2 and a movable side mold 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centering structure used for general molding dies (including press dies and resin molding dies), particularly video discs, CDs, and Ds.
The present invention relates to a centering structure of a disk mold for injection molding a disk substrate for a recording medium such as a VD (digital video disk).

[0002]

2. Description of the Related Art A resin molding die attached to an injection molding machine is manufactured by engraving a cavity, a sprue, and a runner on one or both of mold plates forming a mating surface of a fixed mold and a movable mold. To be done. In this case, if the mold is displaced on the mating surface of the cavity forming the shape of the molded product, defects such as burrs are generated on the mold mating surface. For this reason, it is necessary to be careful in centering the dies for aligning the fixed-side dies and the movable-side dies.

Particularly, in a disc die for injection-molding a disc substrate, a male cutter and a female cutter are provided for punching a hole at the center of the disc, and the clearance is machined so that the maximum clearance is 15 μm.

Therefore, when the fixed side mold and the movable side mold are misaligned by 15 μm or more, the inner diameter hole of the disc plate is opened,
That is, when the gate is cut, the male cutter and the female cutter interfere with each other, causing galling on either one or both.

Generally, in the molding die, as shown in FIGS. 1 and 5, the guide pins 4 and the guide bushes 5 are arranged opposite to each other at the four corners of the die, whereby the stationary die 2 and the movable die 2 are movable. It serves as a guide for centering the side mold 3 and opening / closing the mold.

Further, in the disk mold, in order to precisely align the fixed side mold 2 and the movable side mold 3 with each other, as shown in FIG. 6, a guide pin 4 and a guide bush 5 are provided. Tapered portions 4a and 5a are formed on and, and the tapered portions are brought into contact with each other to perform mold matching and improve the positional accuracy.

In this case, as shown in FIG. 7, the guide pin 4 and the guide bush 5 are fitted to each other, and the guide pin 4 and the guide bush 5 are guided to the step portion 9a of the mounting plate 9 for fixing the mirror surface plate which is the fixed side mold. The guide bush and the respective tapered portions of the guide pin are in surface contact with each other at a position where the shoulder portion 4b of the rear end flange portion of the pin 4 abuts.

However, in particular, in the case of a disk mold, even if the deviation is as small as 15 μm, the taper portion is partially abutted, and as described above, galling occurs between the male cutter and the female cutter during molding. Further, even a single component such as a taper pin or a bush has a dimensional tolerance of 5 μm, and therefore, an error of several tens of μm may occur after the components are assembled.

Further, even if the mold can be assembled within 15 μm, when actually using the mold,
Since the mold temperature is maintained at about 150 ° C, fluctuations due to thermal expansion also occur with the temperature rise. Therefore, it is necessary to check and finely adjust after the assembly temperature is raised.

Fine adjustment for this purpose is conventionally performed in the following procedure.

Taper pin 4 as a guide pin for the mold
The guide bush 5 and the guide bush 5 have a shape as shown in FIG. 6. First, the four guide pins and the guide bush are set to have the same contact strength at the tapered portions.

For this reason, a thin abrasive powder such as red abrasive or blue check paint is thinly applied to the contact surface of the taper portion on the bush side in a clamped state by the mold temperature and the mold clamping force at the time of molding, At the time of adjusting the opening / closing operation of the die, the paint is finely adjusted so that the four paints have a substantially uniform amount of paint on the tapered portion of the guide pin, that is, the tint is the same.

Conventionally, the contact between the four tapered portions of the guide pins is strong, that is, the a-face of the guide pin having a darker paint color than the other tapered portions is ground,
In addition, the taper pin is separated from the bush by plating the b surface, or conversely, the four taper parts are combined and not hit, or the b surface of the taper pin with a very thin color is polished, Further, by plating the a surface, the contact of each guide pin is finely adjusted according to the actual product.

[0014]

However, with this method, fine adjustment is troublesome, and plating treatment is required regardless of whether the a-face or the b-face of the guide pin is polished. Also, it takes a long time to spend on the plating process,
Moreover, it was difficult to reduce the manufacturing cost.

In view of such circumstances, the present invention improves the structure of the guide pin and facilitates the adjustment of the centering of the mold, and the mold is provided with a split-integral type centering adjustment guide pin. Is intended to provide.

[0016]

In order to achieve the above object, the present invention provides a mold having a guide bush and a guide pin, wherein the guide bush and the guide pin have tapered portions that abut each other. , At least one of the guide pins is separated into a pin front portion having the taper portion and a pin rear portion having a polishing seat portion on the front surface, and the pin rear portion is passed through a screw hole provided in the pin front portion. It is characterized by comprising a split guide pin capable of screwing a fastener through the central hole.

As a result, the guide pin has a split type structure in which the pin front portion and the pin rear portion are connected by fasteners such as bolts. The guide pin can adjust the length from the front surface of the pin rear portion that abuts the mounting plate of the mold to the taper portion of the pin front portion by polishing the seat portion at the rear portion of the pin.

According to a second aspect of the present invention, at least one of the guide pin and the guide bush is a guide pin and a guide bush in which a central axis of at least one of a pin front portion and an inner hole which fit with each other is positioned in a mold. It is characterized in that it is displaced with respect to the axis of each outer diameter portion.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a partial side view showing a cross section of a main part of the present invention when viewed from the lateral direction of a mold.

The disk mold 1 is attached to an injection molding machine and is used for injection molding a disk substrate for a recording medium such as a video disk, a CD, and a DVD (digital video disk). The parting line ( P.
L) is divided into a fixed side mold 2 and a movable side mold 3.

In the mold 1, as a centering guide when the fixed mold 2 and the movable mold 3 are opened and closed,
A guide pin 4 (also referred to as a taper pin) and a guide bush 5 are arranged facing each other at the four corners of the mold. As a result, the centering of the stamper 6, the movable die 3, and the male cutter 7 and the female cutter 8 described later is surely performed.
Here, although the guide pin 4 and the guide bush 5 are provided at the four corners of the mold 1, the guide pin 4 and the guide bush 5 are provided.
Requires at least two pairs of configurations.

In the centering structure of the mold of the present invention, as shown in FIG. 2, the guide pin 4 is divided by the c-face which abuts on one mounting plate 9 of the mold, and the pin front part 10 and the pin rear part are divided. It consists of 20. Further, the guide bush 5 has an inner hole having a tapered portion 5a as in the conventional case.

The pin front portion 10 of the guide pin 4 is composed of a tip guide portion 11 of a cylindrical small diameter portion, a taper portion 12, and a rear end flange portion 14 having a central screw hole 13, and a pin rear portion 20 is substantially formed on the front surface. A polishing seat portion 21 having the same diameter as that of the rear end flange portion 14 and a thickness of about 1 mm is provided, and is formed of a large-diameter cylindrical portion having a stepped hole 22 penetrating in the central portion.

The pin front portion 10 and the pin rear portion 20 are connected by a fastener 15 such as a bolt to form an integral guide pin. The guide pin 4 is formed by polishing the seat portion 21 of the pin rear portion 20 so that the front portion of the pin rear portion 20 that abuts the mounting plate 9 of the mold extends from the tapered portion 12 of the pin front portion 10.
The length D (see FIG. 1) can be adjusted. Therefore, the seat portion 2 provided on the pin rear portion 20 of the guide pin 4 with a strong hit
The positional deviation between the male cutter 8 and the female cutter 7 of the disk mold is corrected by finely adjusting the contact of the taper portion 12 only by polishing 1. Further, when there is no polishing machine, a washer-shaped shim is inserted into the seat portion 21 of the guide pin 4 which has a weak contact, and thus the tapered portion 12 of the guide pin 4 is inserted.
The hit can be finely adjusted, and this adjustment can be easily performed by the user. Further, in the embodiment of the present invention, the centering adjustment guide pins are all split type,
For example, only one of the four guide pins may be a split type guide pin.

Further, each of the four guide pins 4 only needs to contact the entire circumference of the tapered portion, but when there is a portion that partially abuts the tapered portion 12, that is, the x and y dimensions in FIG. Fixed mold 2 and movable mold 3
However, it may be out of order by about 10 μm due to processing error, assembly error, etc. Then, one side of the taper, that is, a strong hit portion and a weak hit portion may occur in one guide pin 4.

As a countermeasure against this, as shown in FIG. 3, in the pin front portion 10 of the guide pin 4, the rear end flange portion 14 with respect to the central axis A of the tip guide portion 11 and the tapered portion 12.
By displacing the axis B of P from about 5 to 10 μm from the center, when a strong hit part and a non-hit part are formed, the guide pin 4 is rotated and set at a predetermined position. Fine adjustment is possible according to the actual product.

Further, the guide pin 4 set in this case
It is preferable that four or more set holes 30 are provided in the rear end flange portion 14 of the front portion of the pin and the set bolts 31 provided on the mounting plate 9 of the mold are used so as not to deviate. To do so.

Although the axis line on the guide pin side is displaced here, the axis line may be displaced on the guide bush side. Therefore, in a preferred embodiment of the present invention,
At least one of the guide pin 4 and the guide bush 5 has a pin front portion 10 and / or an inner hole that fits with each other, or one of the guide pins 4 and guide bush 5 has an outer diameter that is set in the mold. It is designed to be displaced with respect to the axis of the part.

Disk mold 1 centered in this way
As shown in FIG. 1, the mirror side plates 16 and 17 which are a pair of mold plates arranged to face the mating surfaces of the fixed side mold 2 and the movable side mold 3, and one of these mirror side plates. A stamper 6 attached via an outer peripheral stamper retainer 18 is provided, and a cavity 19 filled with molten resin is formed between the stamper 6 and the other mirror surface plate 17 facing the stamper 6.

A sprue bush 24 is provided at the center of the stationary die 2, a meskatter 8 is arranged on the outer periphery thereof, and a stamper holder 25 for pressing the inner peripheral edge of the stamper 6 is arranged on the outer side of the meskatter 8. Has been done. The stamper holder 25 is connected to a holding device 26 for removably attaching the stamper 6 to the stationary mold 2, and the pinion 27 and the bevel gear 28 can be driven to raise and lower the stamper holder 25. Further, on the sprue bush 24, a locate ring 29 that determines the mounting position of the fixed mold 2 is arranged.

The movable mold 3 on one side is separated from the fixed mold 2 by a movable mounting plate 31 mounted on the movable plate in order to approach the fixed mold 2 via the intermediate plate 32. A movable side mirror surface plate 17 as one template that is detachably attached, and a mounting frame for fixing the outer peripheral stamper retainer 18 while holding the movable side mirror surface plate 17 at a predetermined position, which is arranged on the outer periphery of the mirror surface plate. 33 is provided.

Further, in the through hole at the center of the movable side mold 3,
The ejector pin 34, the male cutter 7, and the ejector sleeve 35 are coaxially arranged. The male cutter 7 cooperates with the female cutter 8 to punch the inner diameter of the disc,
To separate the sprue from the disk substrate,
The ejector pin 34 is for ejecting the punched sprue, and the ejector sleeve 35 is for releasing the punched disk substrate from the movable side mold.

As described above, by applying the guide pin for centering adjustment of the present invention described above to the mold, the contact between the guide pin and the tapered portion of the guide bush can be adjusted, so that the male cutter 7 and the female cutter can be adjusted. 8 mating,
The stamper 6 and the cavity 19 can be accurately aligned on the parting surfaces.

[0034]

As is apparent from the above description,
The present invention, the centering adjustment guide pin is composed of a split type guide pin, and it is possible to adjust the contact of the taper portion by simply polishing the seat portion formed at the rear portion of the pin,
The centering work, which has been troublesome in the past, can be performed easily and accurately.

[Brief description of drawings]

FIG. 1 is a partial side view of a disk mold including a guide pin for centering adjustment according to the present invention.

FIG. 2 is a diagram showing a divided configuration of a guide pin for centering adjustment of the present invention.

FIG. 3 is a configuration diagram showing a pin front part of the guide pin of the present invention with the axis line displaced.

FIG. 4 is a partial cross-sectional view showing a mounting structure in the case where a setting hole is provided in the front portion of the pin of FIG.

FIG. 5 is a schematic view showing an arrangement of guide pins in a molding die.

FIG. 6 is a configuration diagram showing a structure of a guide pin and a guide bush of a conventional example.

7 is a cross-sectional view showing a state in which the guide pin and the guide bush of FIG. 6 are combined.

[Explanation of symbols]

 1 Disc Mold 2 Fixed Side Mold 3 Movable Side Mold 4 Guide Pin 5 Guide Bushing 10 Pin Front Part 12 Tapered Part 13 Central Screw Hole 15 Fasteners 16, 17 Mirror Plate 19 Cavity 20 Pin Rear Part 21 Seat Part 22 Stepped Hole

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication // B29L 17:00

Claims (2)

[Claims] 1. A cavity is formed in a mold plate which is disposed between a fixed-side mold and a movable-side mold so as to face each other, and at least two pairs of guide bushes and guides are used as a centering guide when opening and closing the both molds. In a die including a pin, the guide bush and the guide pin have tapered portions that come into contact with each other, and at least one of the guide pins is provided.
One is separated into a pin front part having the taper part and a pin rear part having a polishing seat part on the front surface, and is fastened to a screw hole provided in the pin front part through a center hole penetrating the pin rear part. A mold provided with a guide pin for centering adjustment, characterized in that the mold comprises a split guide pin with which a tool can be screwed. 2. The front portion of the guide pin has a tip guide portion,
The guide bush has an inner hole having a taper portion, and the guide bush has an inner hole having a taper portion, and at least one of the guide pin or the guide bush has a pin front portion and an inner hole that are fitted to each other. The guide pin for centering adjustment according to claim 1, wherein both or one of the center axes is displaced from the axes of the outer diameter portions of the guide pin and the guide bush positioned in the mold. Mold to be equipped.