JP2948951B2 - Mold press equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold press for use in, for example, resin molding of semiconductor parts.

[0002]

2. Description of the Related Art A conventional example of this type of mold press apparatus is described below.
As shown in FIG . That is, an upper plate 4 having an upper die 3 is fixed to an upper end of a tie bar 2 erected on the lower plate 1, and a movable member having a lower die 5 is provided between the lower plate 1 and the upper plate 4. A plate 6 is provided to be vertically movable along the tie bar 2. Further, on the lower plate 1, for example, two hydraulic cylinders 7 for driving the mold for moving the moving plate 6 up and down are provided. It is supposed to do.

A plunger 8 for loading resin into the cavity is provided in the lower die 5, and a hydraulic cylinder for loading the resin for driving the plunger 8 is provided at the center of the lower surface of the moving plate 6. 9 are provided.
Thus, the resin material charged into the lower mold 5 is injected under pressure into the cavity of the closed mold.

There are circumstances such as semiconductor parts being manufactured in a clean room. In recent years, the above-described hydraulic cylinders 7 and 9 have been used in order to improve the cleanliness and maintainability.
Instead of this, conversion to an electric type using a motor as a drive source has been attempted. In this case, a so-called ball screw mechanism is generally employed as a means for converting the rotation of the motor into a linear movement such as the vertical movement of the movable plate 6 or the vertical movement of the plunger 8.

[0005]

When a motor and a ball screw mechanism are used for vertically moving the moving plate 6, the two hydraulic cylinders 7 for driving the mold shown in FIG. If the moving plate 6 is moved up and down at two places instead of the screw mechanism, a problem arises in that uniform torque and feed amount cannot be obtained at the two places. This is considered to be because when the torque of the motor is transmitted to the two ball screws via the timing belt and the gear, the torque becomes uniform due to backlash and distortion of the timing belt and the gear.
If such torque non-uniformity occurs, the mold clamping force differs between left and right portions in the drawing, resulting in molding defects such as burrs.

Therefore, when a ball screw mechanism is used for driving the mold, one ball screw mechanism is connected to the lower mold 5.
It is desirable that the mechanism be provided corresponding to the center of the (moving plate 6).

On the other hand, a ball screw mechanism is also provided at one position corresponding to the center of the moving plate 6 in order to apply a uniform load to the plurality of plungers 8 in the mechanism for loading the resin. It is desirable to have a mechanism.

[0008] Under such circumstances, it is considered that:
For example, the mold driving mechanism is configured as shown in FIG. 4, that is, a movable plate 12 is provided so as to be vertically movable along a tie bar 11 erected on the lower plate 10. A ball screw mechanism for vertically moving the moving plate 12 is provided on the lower plate 10 by rotating the ball screw 13 as shown in FIG. The moving plate 12 is configured to move up and down via the connecting body 15. The ball screw 13 is erected corresponding to the center of the moving plate 12 and is supported by the bearing 16 in the lower plate 10.
At the lower end of the ball screw 13, a pulley 17 that receives a rotational force of a motor or the like (not shown) is fixed by a shaft nut 18, and is connected to a driving source (for example, a motor) by a belt 19.

By rotating the ball screw 13,
The moving plate 12 is moved up and down via a nut 14 screwed to the ball screw 13. Therefore, a gap between the moving plate 12 and the lower plate 10 that is longer than the length A of the nut is required. Also, the ball screw 13
Needs to protrude from the upper end of the nut 14 by at least a vertical stroke. Further, if the ball screw mechanism for loading the resin is provided corresponding to the central portion of the moving plate 12, both ball screws are arranged vertically coaxially, so that the entire apparatus becomes large in the vertical direction. I will.

Further, on the lower surface of the lower plate 10, there is provided a timing belt or a gear for rotating and driving the ball screw, and it is necessary to provide a gap for replacing the belt or the gear with the floor of the work place. . This will further increase the size in the vertical direction, resulting in deterioration of workability and the like.

The present invention has been made in view of the above circumstances, and an object of the present invention is to use a driving source for driving a mold and a resin as a motor to improve cleanliness and maintainability. It is an object of the present invention to provide a mode press device capable of preventing the size from increasing in the direction.

[0012]

According to the present invention, there is provided a mold press apparatus comprising: an upper plate and a lower plate fixedly arranged to face each other vertically; and a movable member provided between the upper plate and the lower plate so as to be vertically movable. A plate, an upper die provided on the lower surface of the upper plate, a lower die provided at the center of the upper surface of the moving plate and forming a forming die together with the upper die, and a central portion of the moving plate in the lower plate. A mold driving nut rotatably supported and rotatably driven by a driving mechanism, and a mold driving nut screwed to the mold driving nut by rotating the mold driving nut below the moving plate . And a connecting body that moves up and down together with the moving plate via a feed screw . In addition, the center of the feed screw for driving the mold is
A hollow screw for driving the mold having a hole larger than the diameter of the feed screw shaft is effective for coaxial arrangement of the resin loading mechanism.

[0013]

According to the present invention , when the mold driving nut is rotationally driven by the driving mechanism , the mold driving feed screw, one end of which is fixed to the moving plate by the connecting body , moves up and down , thereby moving the upper mold and the lower mold. The mold is clamped. In this case, the Ji mold driving feed ne <br/>, since <br/> provided corresponding to the central portion of the moving plate, it is possible to obtain a uniform clamping force. The mold drive feed screw protrudes toward the lower surface side of the lower plate when the moving plate is lowered with respect to the nut supported in the lower plate. Therefore, the gap (gap) between the lower plate and the moving plate must be reduced. Can be.

Further, by the mold driving the feed screw to the hollow, resin loading mechanism is also the structure for rotating the nut in the same manner and the mold drive mechanism, feed resin loading feed screw type drive
If so as to enter into the threaded shaft Ri, resin loading feed screw and mold driving the feed screw can be coaxially arranged, requires less space for both the feed screw overlap. Therefore, the whole can be downsized in the vertical direction.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows only a mold driving section corresponding to claim 1, and FIG. 2 shows an embodiment in which a resin loading mechanism according to claim 2 is provided.

First, in FIG. 1, the lower plate 21 having a rectangular shape is installed so as to be floated by a dimension B from the floor surface 20 of the work place via legs (not shown). Four tie bars 22 are erected at four corners of the lower plate 21, and an upper plate 23 is fixed to an upper end of the tie bar 22 so as to face the lower plate 21.

A similar rectangular moving plate 24 is provided between the upper plate 23 and the lower plate 21 so as to be vertically movable along the tie bar 22. An upper die 25 is provided on the lower surface of the upper plate 23, and a lower die 26 which forms a forming die together with the upper die 25 is provided at the center of the upper surface of the movable plate 24.

The lower plate 21 is provided with a mechanism for moving the movable plate 24 up and down to clamp and open the mold as follows. That is, a mold driving nut 27 is rotatably supported by bearings 28a, 28b, and 28c in the center of the lower plate 21. The pulley 29 is attached to the lower end of the nut 27 protruding from the lower surface of the lower plate 21.
The motor 9 is driven to rotate by a drive mechanism including a motor and a reduction mechanism (not shown) via a belt 30 stretched over the belt 9. The nut 27 is provided with a mold driving feed.
A feed screw 31 constituting a screw is screwed.

On the other hand, a connecting body 32 is attached to the center of the lower surface of the moving plate 24 by, for example, bolting. An upper portion of the feed screw 31 is fixed to a lower portion of the connecting body 32. When the nut 27 is rotationally driven, the feed screw 31 moves up and down, so that the connecting body 32 moves up and down together with the moving plate 24. FIGS. 1 and 2 show a state where the feed screw 31 is located in a mold open state in which the feed screw 31 is lowered to the lowest position.
The lower end of the feed screw 31 protrudes from the lower surface of the lower plate 21 and the lower surface of the pulley 29 attached to the lower end of the nut 27, and descends to a position where it does not contact the floor surface 20. Next, an embodiment in which a resin loading mechanism is added will be described with reference to FIG.

A center portion of the feed screw 31 is hollow, and a resin loading nut 33 is provided below the center portion of the connecting body 32.
Are rotatably supported by bearings 34a and 34b.
The nut 33 is provided with a pulley 3 at the upper end of the nut 33.
5 is attached, and is rotatably driven by a drive mechanism including a motor and a reduction mechanism (not shown) via a belt 36 stretched over the pulley 35.

The nut 33 has a feed screw for resin loading.
Are screwed together, and the upper end of the feed screw 37 is fixed to the plunger 38. The plunger 3 prevents the feed screw 37 from rotating due to the rotation of the nut 33.
A guide mechanism 39 is provided on the side surface of the nut 8. When the nut 33 is driven to rotate by this, the feed screw 37 moves up and down, so that the plunger 38 moves up and down.

The feed screw 37 for loading the resin enters into a hole provided at the center of the feed screw 31 for driving the mold when it is lowered, and the two feed screws 31 and 37 are configured to overlap coaxially. . Next, the operation of the above configuration will be described.

When the setting of the material is completed, first, the motor of the driving mechanism is driven, and the mold driving nut 27 is driven to rotate. Thus, when the connecting body 32 is raised together with the moving plate 24 via the feed screw 31 and the upper mold 25 and the lower mold 26 are mated, the mold is clamped at a predetermined pressure. In this case, the mold driving nut 27, in other words, the feed screw 31 for transmitting the ascending moving force is
4 (molding die)
A uniform clamping force can be obtained for the entire molding die.

When the mold clamping is completed, a resin loading rotation drive mechanism (not shown) is driven to rotate the resin loading nut 33 via the belt 36. With this,
The plunger 38 is raised while being guided by the guide mechanism 39 via the feed screw 37, and the resin is injected. Also in this case, since the plunger 38 and the feed screw 37 are provided at the center of the movable plate 24, an even load (push-up force or injection force) can be applied to the inside of the mold. As a result, when the molding operation is completed, the motor of the rotary drive mechanism is driven to rotate in the opposite direction, contrary to the above. With this,
After returning to the mold open state of FIGS. 1 and 2 and removing the molded product, the above-described operation is repeated.

[0025] Thus, according to this embodiment, the co <br/> driving the drive and the resin loading mechanism of the lower mold 26 (the plunger 38), so were of electric that a motor as a driving source Unlike the conventional hydraulic cylinders using the hydraulic cylinders 7 and 9, the cleanliness and the maintainability can be improved, and the apparatus is suitable for use in a clean room.

The mold driving feed screw 31 is arranged at the center of the moving plate 24 and the feed screw itself is moved up and down, so that the space between the floor surface 20 and the lower plate 21 becomes necessary. Can be effectively utilized,
Unlike the configuration in which the feed screw is rotated, it is possible to prevent the entire apparatus from being enlarged in the vertical direction.

The feed screw 37 for resin loading is also arranged corresponding to the center of the movable plate 24, and the center of the feed screw 31 for driving the mold is made hollow so that the feed screw for resin loading is inserted into the feed screw. This has the effect of preventing the vertical size from increasing. As a result, good workability can be ensured. In addition, the present invention is not limited to resin molding of semiconductor components, and can be appropriately modified and implemented without departing from the gist, such as being applicable to various moldings.

[0028]

As is apparent from the above description, according to the mold press apparatus of the present invention, the feed screw (nut) for driving the mold is arranged corresponding to the center of the moving plate, and the drive screw for driving the mold is provided. Since the nut is rotated instead of the feed screw, the motor can be used as a drive source to improve cleanliness and maintainability, and prevent the entire device from becoming large in the vertical direction. It has an excellent effect that it can be done.

Also, if the center of the mold driving feed screw is hollow and the resin loading mechanism is configured to rotate with a nut, the resin loading mechanism is also arranged corresponding to the center of the moving plate and is coaxial with the mold driving feed screw. Regardless of the arrangement, the above effect can be obtained.

[Brief description of the drawings]

FIG. 1 is a partially longitudinal whole front view of a mold driving mechanism showing an embodiment of the present invention.

FIG. 2 is a partial longitudinal sectional front view showing an embodiment to which a resin loading mechanism of the present invention is added.

FIG. 3 is an equivalent view of FIG. 1 using a hydraulic mechanism.

FIG. 4 is a front view showing a conventional example using a feed screw for a drive mechanism.

[Explanation of symbols]

In the drawing, 21 is a lower plate, 22 is a tie bar, 23 is an upper plate, 24 is a moving plate, 25 is an upper mold, 26 is a lower mold, 27 is a mold driving nut, 31 is a mold driving feed screw, and 32 is a connection. 33, a resin loading nut, 37, a resin loading feed screw, 30, 36 a toothed belt,
8 denotes a plunger.

Claims (2)

(57) [Claims] 1. An upper plate and a lower plate fixedly arranged in a vertically opposed state, a movable plate movably provided between the upper plate and the lower plate, and a lower surface of the upper plate. An upper die, a lower die provided at the center of the upper surface of the moving plate and forming a forming die together with the upper die, and rotatably supported by the driving mechanism in the lower plate corresponding to the center of the moving plate. A driven mold driving nut, which is moved up and down together with the moving plate via a driving screw for driving the mold, which is screwed to the nut for driving the mold, by rotating the nut for driving the mold below the moving plate. A mold press apparatus comprising: 2. The mold press device according to claim 1, wherein the mold drive feed screw is a hollow mold drive feed screw having a hole in the center thereof having a diameter equal to or larger than the resin loading feed screw shaft diameter.