JP2709874B2 - Injection molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding machine having a vertical injection unit.

[0002]

2. Description of the Related Art FIG. 1 shows an injection molding machine 4 having a vertical mold clamping unit 1 and an injection unit 3 for injecting a parting line into a mold 2 attached thereto. In this type of injection molding machine 4, the nozzle of the injection unit 3 can be touched to the mold 2 of the mold clamping unit 1 from any of the four side surfaces of the mold 2 in principle. Great nature. Further, since this and the floor area occupied by the injection molding machine 4 as a whole are relatively small, an injection molding machine having a vertical injection unit is often incorporated in an assembly line.

[0003] Such a situation creates many installation layouts in which the injection unit 3 is arranged so that the nozzle 5 is directed to the movement path or work area of the worker. On the other hand, in the vertical mold clamping unit 1, when the upper platen 6 is moved upward,
The injection axis a of the injection unit 3 penetrates the mold clamping unit 1 and directly reaches the moving path and the work area.

For this reason, injection is performed when the mold clamping unit 1 is in the mold open state, or careless purging operation is performed without sufficient sealing when the upper platen 6 is moved upward. Then, there is a danger that the worker who is present in front of the nozzle 6 with the mold clamping unit 1 interposed will be exposed to the high-temperature purge resin (the state shown by a chain line in FIG. 1). Particularly, in the case of the injection molding machine 4 which is programmed to automatically perform the purging process, there is a great danger when a resin having a high fluidity or a resin which easily generates gas is purged.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an injection molding machine having a vertical mold clamping unit which does not cause a worker to be exposed to a purge resin even if careless purging occurs. .

[0006]

Means for Solving the Problems A vertical mold clamping unit,
An injection unit for performing parting line injection, a purge shutter disposed so as to protrude and retract in front of a nozzle of the injection unit, and a shutter driving mechanism are provided. The shutter drive mechanism automatically arranges the purge shutter in front of the nozzle when the nozzle touch of the injection unit is released.

[0007] A structure in which the purge shutter is pulled out of the storage location with the upward movement of the upper platen and is disposed in front of the nozzle is one preferred embodiment.

[0008]

The shutter drive mechanism arranges the purge shutter in front of the nozzle of the injection unit every time the nozzle touch is released. The purge shutter shuts off the nozzle of the injection unit from the front.

[0009]

FIG. 2 shows a first embodiment. Injection molding machine 4
Has a vertical mold clamping unit 1 and an injection unit 3 for parting line injection, and has the same configuration as a conventional injection molding machine of this type.

In the drawing, the mold clamping unit 1 is in a mold open state, and the injection unit 3 is in a state in which the nozzle 5 is separated from the side surface of the mold 2 and the nozzle touch is released. A purge shutter 7 projects in front of the nozzle 5 to shut off the front. The purge shutter 7 is a thin stainless steel plate whose base is guided by the base 8 of the mold clamping unit 1 so as to be able to move smoothly in the vertical direction. The purge shutter 7 is disposed between the side surface of the mold 2 and the nozzle 5, and is moved up and down by a shutter driving mechanism 9 so as to protrude and retract in front of the nozzle 5.

The shutter driving mechanism 9 includes an air cylinder 10
And an operating valve 11 and an air pressure source P, and a purge shutter 7 is attached to a piston rod 12 of an air cylinder 10.
The base is fixed. The air cylinder 10 is a single-acting type, and has a return coil spring 13 disposed therein. Reference numeral 14 denotes a relief valve.

The operation valve 11 is a normal switching valve, and the operation lever 15 is disposed at a position separated from the side surface of the mold 2 by a predetermined distance, and is operated according to the nozzle position of the injection unit 3. I have. That is, the predetermined distance is a position at which the purge shutter 7 is retracted from the front of the nozzle 5 immediately before the nozzle 5 collides with the purge shutter 7 at the time of nozzle touch. Is a position where the purge shutter is disposed in front of the nozzle 5 immediately after passing through the purge shutter position due to the backward movement.

Accordingly, when the injection molding machine 4 is in the injection molding process and the nozzle touch is performed, the operation valve 11 of the drive mechanism 9 is operated by the nozzle 5 in the direction of supplying air to the air cylinder 10. Therefore, the purge shutter 7 is retracted by the air cylinder 10 and does not hinder resin injection into the mold 2. At this time, since the mold clamping unit 1 is in the mold clamping state, the resin injected from the nozzle 5 is not purged forward beyond the mold 2.

On the other hand, injection of resin into the mold 2,
When the process such as cooling is completed, the nozzle touch is released, and the mold clamping unit 1 is opened to remove the molded product. When the nozzle 5 is retracted by releasing the nozzle touch, the operation valve 11 is released. Is operated in the direction of bleeding air from the cylinder 10, and the purge shutter 7 is immediately actuated by the action of the coil spring 13 of the single-acting cylinder 10.
And shuts off the nozzle 5 from the front.

This operation is performed by executing and canceling the nozzle touch.
That is, the purge shutter 7 is arranged in front of the nozzle 5 every time the mold opening and closing of the mold clamping unit 1 is repeated, and each time the mold clamping unit 1 opens the mold. In addition, when the nozzle touch is released, such as at the time of mold replacement or regular purging, the nozzle
The front of is blocked. Thus, even if the mold clamping unit 1 is in the mold open state, the worker does not take care of inadvertent resin purging from the nozzle 5, and the safety of the worker is maintained.

FIGS. 3 to 6 show a second embodiment. The configuration of the entire injection molding machine 4 is the same as that of the first embodiment.
In this embodiment, the purge shutter 7 is constituted by a screen 16 made of a heat-resistant cloth in which a metal wire is woven, and is taken up in a take-up container 17. The take-up container 17 has a mainspring inside, and constantly urges the screen 16 in the take-up direction. A cutout window 19 is formed at the center of the screen 16 in the width direction to allow the nozzle 5 to penetrate the screen 16 in the longitudinal direction of the screen 16 from the end of the screen 16.

In this embodiment, the take-up container 17 is fixed to the lower platen 18 of the mold clamping unit 1,
The upper end of the screen 16 pulled out from this is fixed to the upper platen 6. The screen 16 is located between the mold 2 and the nozzle 5 from which the nozzle touch has been released.

When the mold clamping unit 1 is in the mold closed state (FIG. 3), the screen 16 is located in front of the nozzle 5, and the nozzle 5 penetrates the cutout window 19 and makes a nozzle touch on the mold 2. (Figure 5). When the mold clamping unit 1 is in the mold open state (FIG. 4), the screen 16 is pulled out upward and the cutout window 19 also moves upward, so that the screen 16 exists in front of the nozzle 5 at the retracted position. I do.

Thus, even if there is an inadvertent purge of the resin as described above, the resin is received by the screen 16 and
There is no danger of the operator being exposed to the purge resin (FIG. 6).

The drawn-out screen 16 is automatically drawn into the container 17 by the spring provided in the take-up container 17 as the upper platen 6 is lowered when the mold clamping unit 1 is brought into the mold-clamped state. Therefore, during the molding process, the screen 16 is taken in and out each time the mold clamping unit 1 opens and closes the mold. Then, the front of the nozzle 5 is shut off by the screen 16 every time the mold opening operation is performed. In addition,
When the nozzle touch is released, such as at the time of mold replacement other than the injection molding operation or at the time of regular purging, the front of the nozzle 5 is shut off regardless of the opening and closing of the mold.

In the case of the second embodiment, the shutter driving mechanism 9 includes a mainspring spring inside the take-up container 17 and a lower platen 18.
Screen 16 with a take-up container 17
And has an advantage that it does not require a separate air cylinder or the like for the purge shutter.

The above is the embodiment.

In the first embodiment, the shutter driving mechanism 9
The power source may be an electric motor or a solenoid. In the first embodiment, the purge shutter 7 and the shutter driving mechanism 9 are provided on the mold clamping unit 1 side, but may be on the injection unit 3 side. Screen 16 of the second embodiment
The upper end may be attached to the side surface of the mold 2.

In the second embodiment, the screen 16 may have a folding structure such as a general window blind, or may have a lower portion having a bellows structure. In the first and second embodiments, the purge shutter 7 may be disposed on the side of the mold 2 opposite to the nozzle 5 (broken line in FIG. 2). However, in this case, it is necessary to prevent the removal of the molded product and the replacement of the mold 2 so as not to hinder the removal.

[0025]

As described above, in an injection molding machine provided with a vertical mold clamping unit and arranged in a free layout, even if careless purging occurs, the purge resin reaches the movement path and the work area of the worker. The safety of the injection molding machine is high.

[Brief description of the drawings]

FIG. 1 is a front view of a conventional example.

FIG. 2 is a front view mechanically showing the first embodiment.

FIG. 3 is a side view of a main part of the second embodiment (when a nozzle is touched).

FIG. 4 is a side view of a main part of the second embodiment (when nozzle touch is released).

FIG. 5 is a schematic front view of a main part of the second embodiment (when a nozzle is touched).

FIG. 6 is a schematic front view of a main part of the second embodiment (when nozzle touch is released).

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Mold clamping unit 2 Die 3 Injection unit 4 Injection molding machine 5 Nozzle 7 Purge shutter 9 Shutter drive mechanism 16 Screen

Claims (2)

(57) [Claims] An injection unit for injecting a parting line into a mold attached to a vertical mold clamping unit, a purge shutter and a shutter driving mechanism arranged to protrude and retract in front of a nozzle of the injection unit. An injection molding machine wherein the shutter drive mechanism automatically arranges a purge shutter in front of the nozzle when the nozzle touch of the injection unit is released. 2. The injection molding machine according to claim 1, wherein the purge shutter is pulled out of the storage location with the upward movement of the upper platen and is disposed in front of the nozzle.