JPH05192953A - Mold press device - Google Patents

Abstract

PURPOSE:To prevent the damage of a mold by raising a moving plate by the power of a servo motor through a screw to perform mold register and operating the toggle type link provided to the lower part of a transfer device to the driving stopper of the servo motor by a pneumatic cylinder to perform mold clamping. CONSTITUTION:When a servo motor 10 is revolved in the falling state of a moving plate 4, the power of the servo motor 10 revolves screws 9, 9 through a belt 13 and a lower mold 6 is raised to be registed with an upper mold 5. At this time, a transfer device 7 also rises to bring a link and a roller 22 to an extended state. Then, a pneumatic cylinder 29 is operated to press a plate 28 to a stopper 30 through the roller 22 and the transfer device 7 is pushed upwardly to clamp the lower mold 6 and the upper mold 5 under pressure. Therefore, even when foreign matter is grasped between both molds at the time of mold register, said foreign matter can be detected on the basis of the pulse count of the servo motor and the damage of the molds can be prevented and mold clamping pressure can be set with a high accuracy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold pressing apparatus used for resin molding of semiconductors, for example.

[0002]

2. Description of the Related Art Conventionally, as a mold press device used for resin molding of semiconductors, as shown in FIG. 6, a lower plate 1 and an upper plate 2 are provided so as to be vertically movable by using four tie bars 3 as guides. Has been. An upper die 5 is arranged at the center of the lower surface of the upper plate 2, and the moving plate 4
A transfer device 7 is arranged in the center of the lower surface of the. Between the lower plate 1 and the moving plate 4, a hydraulic cylinder 8 is provided around the transfer device 7, for example, on the left and right sides.

When performing mold pressing with the above structure, first, the upper die 5 and the lower die 6 are heated to a constant temperature, and then the hydraulic cylinders 8 are simultaneously actuated to raise the moving plate 4. , The lower mold 6 is pressed against the upper mold 5 to perform mold clamping. In this state, the transfer device 7 injects the molten resin into the mold 5.6, holds it for a certain period of time to solidify the molten resin, and then lowers the moving plate 4, and hence the lower mold 6, to release the resin-molded product. Shape.

[0004]

By the way, a hydraulic cylinder is used to vertically move the moving plate 4, and hence the lower mold 6, and the hydraulic pressure used is 200 to 5 in order to increase the mold clamping force.
It is as high as 00 kgf / cm ² . When using at such a high pressure, if bubble switching is performed in order to change the oil flow, a large vibration is generated in the piping system and a loud noise is produced. If used for a long time in such a situation, oil leakage from the pipe joint will occur without fail, and oil leakage will occur due to wear of the packing even in the hydraulic cylinder. Further, there is concern that the vaporization of the leaked oil may affect the semiconductor, which is a resin molded product. Cleanliness, low noise, required recently for equipment,
It is also a problem for low vibration. Therefore, an object of the present invention is to provide a mold press device for improving the quality of products and improving the environmental resistance.

[0005]

According to the present invention, there are provided an upper plate and a lower plate which are arranged and fixed in a vertically opposed state, and a movable plate which is vertically movable between the upper plate and the lower plate. An upper mold provided at the center of the lower surface of the upper plate, a lower mold provided at the center of the upper surface of the moving plate so as to face the upper plate, a transfer device provided at the center of the lower surface of the moving plate, and the lower mold. A plurality of screws are provided between the plate and the moving plate, and are arranged around the transfer device. The screws are driven by a servo motor that raises and lowers the moving plate to match and open the upper mold and the lower mold. , A toggle type link located below the transfer device and operated by a pneumatic cylinder, and a servo motor arranged opposite to the pneumatic cylinder. It is made of the mold clamping device comprising a motor drive of the stopper.

[0006]

[Function] The power of the servo motor is raised by moving the moving plate through the screw to match the lower mold to the upper mold, and the toggle link at the bottom of the transfer device is operated by the pneumatic cylinder to the stopper of the servo motor drive and the mold is clamped. Do.

In this series of operations, the servomotor has only to have a thrust force of the moving plate, the lower die, and the transfer device. Compared with this, the operating distance is short, but 10
For mold clamping that requires more than twice the thrust, a booster mechanism with a toggle type link is operated by a pneumatic cylinder. At this time, the operation limit of the pneumatic cylinder is adjusted by a stopper driven by a servo motor to adjust the mold clamping pressure.

[0008]

EXAMPLES Examples of the present invention will be described below with reference to FIGS.
Will be described. 1 to 5, the same parts as those in FIG. 6 are designated by the same reference numerals. Therefore, 1 and 2 are a lower plate and an upper plate which are arranged and fixed in a vertically opposed state by the tie bar 3, and 4 is a movable plate which is located between the plates 1 and 2 and is vertically movable with the tie bar 3 as a guide, 5 is an upper die provided at the center of the lower surface of the upper plate 2, 6 is a lower die provided at the center of the upper surface of the moving plate 4, 7 is a transfer device provided at the lower surface of the moving plate 4, and 9 is the plate. 1 and a moving plate 4, a moving plate 4 provided around the transfer device 7, for example, left and right, a screw for driving the lower die 6 in the vertical direction, a servo motor 10 and a pulley 11 at the end of the shaft. ,
A pulley 12 is attached to the lower shaft end of the screw 9,
These pulleys 11 and 12 are connected by a belt 13.

Between the lower surface of the transfer device 7 and the lower plate 1, a mold clamping mechanism of a toggle type link, which is shown in detail in FIGS. 4 to 5, is provided. Is provided with an upper bearing 15 having a structure that can be finely adjusted, and the bearing 15 and the link 1 having a radius R1.
6 are connected by a hinge pin 17.

On the other hand, a lower bearing 18 is provided on the upper surface of the lower plate 1.
Is attached, and the above-mentioned link 16 and the link 19 having the relationship of radius R1 = R2 are connected by a hinge pin 20. The other end of the link 16 and the other end of the link 19 are connected to each other by a hinge pin 21, and a lock 22 is provided at the center of the connecting portion. The link 19 and the hinge pin 20 are fixed by a pin 23, and the pulley 2 is attached to one end of the hinge pin 20.
4 is fixed.

On the other hand, a pulley 26 having the same number of teeth as the pulley 24 fixed to the shaft end of a rotational position detector 25 installed on the lower plate 1 is connected by a belt 27, and the rotational position is the same as the swing angle of the link 19. The relationship that the detector 25 rotates is taken.
Reference numeral 28 denotes a plate for pressing the roller 22 for mold clamping, which is fixed to the rod end of the mold clamping pneumatic cylinder 29.

In the stopper 30, the plate 28 is the roller 22.
When is pressed, it stops on the same axis as it opposes and acts as a stopper. The stop position can be set delicately by power transmission from the servo motor 31 by the gear 32 and the screw 33. ing. Further stopper 3
In 0, the roller 22 can be pushed to release the mold clamping.

Now, in the above structure, when performing mold pressing, when the servo motor 10 is rotated while the moving plate 4 shown in FIG.
1, the pulleys 12 and 12 are rotated via the belt 13 and the screws 9 and 9 are rotated to raise the lower mold 6 and align the mold with the upper mold 5. At this time, the transfer device 7 also rises, and the stroke S is separated from the lower plate 1. In accordance with this, the upper bearing 15 attached to the lower surface of the transfer device 7
Also, the links 16 and 17 and the roller 22 change from the two-dot chain line state shown in FIG. 4 to the solid line shape. In this state, as shown in FIG. 3, the pneumatic cylinder 29 is operated to press the plate 28 against the stopper 30 via the roller 22 to press the transfer device 7 upward by the toggle action, and the lower die 6 located above this. Is pressed against the upper mold 5 and the mold is clamped.

This toggle system is a mechanism for producing a large thrust with a small force, but has a drawback that the stroke is short, and it is slightly due to the upper and lower molds 5 and 6, the moving plate 4, and the transfer device 7 due to the heat of the mold. Causes a dimensional change. In order to prevent the change in the mold clamping force due to this change, the angles θ1 and θ2 of the links 16 and 19 at the beginning of the mold clamping.
Should be approximately constant. For this purpose, after the lower die 6 is fitted to the upper die by the servo motor 10 described above, the nut 14 is rotated to make the link angles θ1 and θ2 equal to the initially planned values. , Pulley 2
4, the value (not shown) of the rotational position detector 25 that is interlocked via the belt 27 and the pulley 26 is read and adjusted. The mold clamping force can be easily changed by changing the stop position of the stopper 30.

Next, when the mold is opened, the links 16 and 19
If the angle when clamping the mold is close to 0, the pneumatic cylinder 29
Even if it is moved backward, the restoring force is weaker than the frictional resistance of the bearing portion. To assist this, the screws 9, 9 are reversely rotated by the servo motor 10 and the mold opening operation is performed, and at the same time, the servo motor 31 is operated to act as the stopper 30. Push the roller 22 to unlock the toggle link.

According to the present embodiment, a relatively small thrust is sufficient, but a servomotor is used for mold matching that requires high speed and high position accuracy, and a toggle type link is used in a pneumatic cylinder at a portion requiring a large thrust called mold clamping. By using two systems that are driven, it is possible to reduce hydraulic pressure and make the equipment cleaner.
It will be possible to reduce vibration and noise. Moreover, since the stopper of the toggle type link is driven by the servo motor, it is possible to set the fine mold clamping pressure, which is effective in terms of product quality. (Other embodiments)

In order to automatically adjust the angle at the beginning of mold clamping, it is possible to adopt a mechanism in which the outer circumference of the nut is a worm wheel 34 and the worm shaft 35 is rotated by a motor 36, as shown in FIGS. Is.

[0018]

As is apparent from the above description, the present invention employs a servomotor drive which has a small thrust but is high speed and easy to control, so that when the upper die and the lower die are aligned, the space between the upper die and the lower die is increased. Even if a foreign object is sandwiched between the two, it is possible to prevent damage to the mold, and it is possible to detect a change in the movement amount due to the foreign matter with respect to the regular mold clamping position by the pulse count of the servo motor.

Therefore, a thin foreign object can be detected, and the mold clamping is a toggle type link mechanism that can output a high output, and a pneumatic cylinder drive that can easily output a large output is used, and the stroke can be controlled by a servo motor drive stopper to achieve a clean. In addition, it has excellent effects of low vibration, low noise, and highly accurate setting of mold clamping pressure.

[Brief description of drawings]

FIG. 1 is an overall front view of a mold clamped state according to an embodiment of the present invention,

FIG. 2 is a side view in which a part of the whole is shown in a mold open state,

FIG. 3 is an overall mold clamping diagram viewed from the same direction as FIG.

FIG. 4 is an enlarged detailed cross-sectional view of the mold clamping portion shown in FIGS. 2 and 3.

5 is a front view of FIG.

FIG. 6 is a view corresponding to FIG. 1 showing a conventional example,

FIG. 7 is a view showing a modified example of adjusting the mold clamping height.

[Explanation of symbols]

1 is a lower plate, 2 is an upper plate, 4 is a moving plate, 5 is an upper mold, 6 is a lower mold,
7 is a transfer device, 9 is a screw,
10 is a servo motor, 25 is a rotational position detector, 29 is a pneumatic cylinder, 30 is a stopper, 31 is a servo motor, and 33 is a screw.

Claims (1)

[Claims] 1. An upper plate and a lower plate, which are arranged and fixed to face each other in an up-down direction, a moving plate vertically movable between the upper plate and the lower plate, and provided in the center of the lower surface of the upper plate. An upper mold, a lower mold provided at the center of the upper surface of the moving plate so as to face the upper plate, a transfer device provided at the center of the lower surface of the moving plate, and between the lower plate and the moving plate. A plurality of screws, which are arranged around the transfer device, are driven by a servo motor that raises and lowers the moving plate to match and open the upper mold and the lower mold, and the lower plate is provided with a screw of the transfer device. A toggle-type clamping device driven by a cylinder having a servo-driving stopper arranged below. Mold press equipment.