JP3477249B2 - Vertical 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 a vertical / vertical injection molding machine in which a vertical mold clamping unit is combined with an injection unit in a vertical direction.

[0002]

2. Description of the Related Art In an injection molding machine, in particular, an electric injection molding machine, a mold clamping unit and an injection unit are arranged in a horizontal shape in which both the mold clamping unit and the injection unit are arranged horizontally.
There is a vertical / horizontal type in which the mold clamping unit has the mold clamping axis as the vertical direction, while the injection unit has the injection axis as the horizontal direction. The horizontal shape is stable and it is easy to perform molding work and maintenance, but the installation area is large. In vertical / horizontal type, the parting line is the injection to the mold, but in principle, nozzles can be touched from four sides to the mold, so make various changes to the combination of the mold clamping unit and the injection unit. This makes it easy to design the layout of injection molding machines that can be installed in the factory. Moreover, the installation area is not so large. However, since parting line injection uses a special mold for the position of the sprue, the mold is expensive and it is inconvenient for hoop molding, which is a long molding.

Therefore, various vertical / vertical injection molding machines have been tried in which a vertical mold clamping unit having the mold clamping axis in the vertical direction is combined with a vertical injection unit having the injection axis in the vertical direction. . Among the vertical / vertical injection molding machines, the one with the vertical injection unit mounted on the upper platen of the vertical mold clamping unit has a small installation area, and the direction of force acting during mold clamping and It is possible to construct an injection molding machine with good performance and a rational direction of force that acts during injection.
The weight of the movable body, which is the part that moves vertically, is large,
There is a problem that a large load is applied to the mold clamping motor (servo motor) not only when the motor is lifted, but also when the motor is lowered while controlling the speed, and the motor is worn out early. In addition, a reliable and large emergency braking device is required to prevent danger and is expensive.

[0004]

SUMMARY OF THE INVENTION The present invention provides a vertical / vertical injection molding machine with a small motor load, a safe vertical / vertical injection molding machine in which a movable body is less likely to fall spontaneously, and a cylinder assembly is replaced. It is an object to provide a vertical / vertical injection molding machine that is easy to manufacture.

[0005]

In a vertical / vertical injection molding machine, a lower platen, a tie bar, an upper platen, and an upper platen are connected via a pulley in which the other end of a wire having one end attached to a balance weight is attached to the upper part of a machine body frame. It is connected to a movable body composed of an injection unit, and the weight of the movable body is almost balanced by a balance weight.

It is preferable to adopt the following configuration. Balance weight is adjustable. Vertical guide plates are provided on both sides of the upper surface of the upper platen so as to face each other, and a base plate is vertically movably mounted on the guide plates. Then, both sides of the injection unit are supported by the horizontal axis on the base plate to allow the injection unit to swivel forward, and the moving part of the nozzle touch mechanism is connected to the base plate.

[0007]

The function of the vertical / vertical injection molding machine in which the weight of the movable body is almost balanced by the balance weight reduces the motor load and prevents the movable body from being suddenly dropped. The structure in which the weight of the balance weight can be adjusted makes it possible to cope with the weight change of the movable body accompanying the die replacement. The configuration in which the injection unit can be swiveled forward facilitates the attachment / detachment of the cylinder assembly.

[0008]

1 to 3 show a vertical / vertical injection molding machine 1 in which a mold clamping unit 3 and an injection unit 4 are formed on a machine body frame 2. The mold clamping unit 3 includes an upper platen 6 (movable platen) above a fixed platen 5 horizontally fixed to the machine body frame 2, and a lower platen 7 below.
(Rear platen) is arranged and these are fixed platen 5
Are connected by four tie bars 8 penetrating slidably in the vertical direction. Then, the lower platen 7 and the fixed platen 5
And a mold clamping mechanism 9 is provided to connect the molds to each other, whereby the molds 10 (a, b) attached to the upper surface of the fixed platen 5 and the lower surface of the upper platen 6 are opened and closed. The mold clamping mechanism 9 is a toggle type in this embodiment and has the same structure as the conventional one. Further, it is driven by the mold clamping motor 11 mounted on the lower platen 7 to expand and contract. That is, the mold clamping unit 3 is arranged in the machine frame 2 with its mold clamping axis a (direction of mold clamping force) as the vertical direction.

The injection unit 4 is mounted above the mold clamping unit 3 with the cylinder assembly 12 facing downward so as to move up and down together with the mold clamping unit 3. That is, the guide blocks 13 are fixed to face both sides of the upper platen 6 of the mold clamping unit 3 in the vertical direction, and the left and right base plates 15 are fitted in the vertical guide holes 14.
Each of the guide protrusions 16 (corresponding to an extruder base) is fitted into the guide hole 14 so as to be vertically movable. Then, the horizontal shafts 17 provided on both sides of the injection unit 4 are pivotally supported by the left and right base plates 15 so as to be rotatable in the front-rear direction, and one guide protrusion 16a is laterally extended to a large extent. The moving portion 19 of the nozzle touch mechanism 18 is coupled to the. The structure of the injection unit 4 itself requires some deformation in the hopper portion, but there is no particular difference from the conventional one.

The nozzle touch mechanism 18 is composed of a moving part 19, a ball screw 20 and a nozzle touch motor 21, and the moving part 19 is provided with a ball nut.
A moving plate 22 screwed to the spring and a spring 23 are provided.
In addition, the movable plate 22 is provided with a stopper 24 that also serves as a guide on the left and right
Equipped with. The ball screw 20 penetrates the guide protrusion 16a without screwing, and the guide protrusion 16a and the ball screw 20 serve as a moving plate 22 screwed to the ball screw 20 via a ball nut, a spring 23, and a guide. Are connected via stoppers 24 of. In this way, the injection unit 4 is coupled to the upper platen 6 of the mold clamping unit 3 by the nozzle touch mechanism 18, and normally the injection axis b (direction of ejection output) is set to the vertical direction, and the mold clamping unit 3 is clamped. It is combined so as to match the axis a.
Reference numeral 25 is a stopper for preventing the injection unit 4 from unexpectedly rotating around the horizontal shaft 17.

Therefore, the mold clamping motor 11 is now available.
Is driven, the toggle link of the mold clamping mechanism 9 expands and contracts, and the movable body 26 including the lower platen 7, the tie bar 8, the upper platen 6 and the injection unit 4 moves up and down (chain line in FIG. 2), and the mold The opening and closing of 10 is performed, and during that period, resin is injected from the injection unit 4 and the molded product is taken out. The sequence of this molding operation is no different from that of the conventional horizontal injection molding machine. Reference numeral 27 is a negative-acting electromagnetic brake that is incorporated in the drive mechanism of the ball screw 20 and operates in the event of a power failure to brake the idle rotation of the ball screw 20, causing the movable body 26 to float in the vertical direction. Is to prevent.

The movable body 26 is provided with a balance weight 28 arranged on the rear side of the body frame 2 and a wire 30 stretched via a pulley 29 attached to the upper portion of the body frame 2.
Are joined by. The balance weight 28 has a structure in which thin plates are removably stacked so that the weight can be almost balanced with the weight of the movable body 26. In FIG. 2, the plane shape is shown by a chain line.

With the above construction, as described above, the movable body 26 is driven up and down by the mold clamping motor 11, and the resin is molded by the operation of the mold clamping unit 3 and the injection unit 4. At this time, since both the mold clamping axis a and the injection axis b are in the vertical gravity direction, bending and positional deviation of each machine part are unlikely to occur. Further, since the weight of the movable body 26 is balanced by the balance weight 28, the load on the mold clamping servomotor is small both when the movable body 26 is raised and when it is lowered. Furthermore, the movable body 2
Since the weight of 6 is balanced by the balance weight 28, even if the movable body 26 falls into a floating state, the movable body 26
Does not fall or drop rapidly.

The nozzle touch is performed by driving the nozzle touch motor 21 and lowering the moving portion 19 by the ball screw 20, and a predetermined touch pressure is maintained by the spring. When the touch is released, the moving portion 19 is raised, the spring extends, and then the lower end of the guide / stopper 24 engages with the guide protrusion 16a from below to pull up the injection unit 4. Touch pressure,
The control of the touch release timing and the like is the same as in the conventional injection molding machine.

Although it is necessary to replace the mold 10 and attach and detach the cylinder assembly 12 as in the conventional case, particularly in the case of the injection unit 4, the stopper 25 is removed and the cylinder assembly 12 is rotated forward about the horizontal shaft 17 to rotate the cylinder assembly. The tip of 12 can be removed by removing it from the area of the fixed platen 5 (FIG. 3).
Chain line). In this case, it is necessary to suspend the injection unit 4 which has been rotated forward from the machine body frame 2 via a chain or the like so as to prevent the injection unit 4 from unexpectedly returning to its original safety.

The above is an embodiment, and the present invention is not limited to the illustrated specific configuration. For example, the mold clamping mechanism 9
May be a direct drive type using a hydraulic ram or an electric direct drive type using a servo motor and a ball screw. Further, when the mold clamping mechanism 9 is a toggle type, a mold thickness adjusting mechanism may be provided between the lower platen 7 and the tie bar 8. Also, in the figure, small accessory devices are omitted.

[0017]

Since it is a vertical / vertical injection molding machine, it has the smallest installation area as compared with a machine of the same scale. Since the weight of the movable body is balanced by the balance weight, the load on the mold clamping servo motor for moving the movable body up and down is small, and the durability is increased. Since the weight of the movable body is balanced by the balance weight, the movable body does not drop rapidly, which is safe, and the braking device for emergency stop requires a light load and is inexpensive. Since the injection unit can swivel forward, work such as attaching and detaching the cylinder assembly can be easily performed.

[Brief description of drawings]

FIG. 1 is a front view with a part omitted.

FIG. 2 is a right side view with a part omitted.

FIG. 3 is a left side view showing a part thereof.

[Explanation of symbols]

1 Vertical / Vertical injection molding machine 2 airframe 3 mold clamping unit 4 injection unit 5 Fixed platen 6 Upper platen 7 Lower platen 8 tie bars 9 Mold clamping mechanism 10 mold 11 Clamping motor 12 cylinder assembly 13 Guide block 14 Guide hole 15 Base plate 16 Guide protrusion 17 Horizontal axis 18 nozzle touch mechanism 19 Moving part 20 ball screw 21 Nozzle touch motor 22 Moving plate 23 spring 24 Guide and stopper 25 stop 26 Movable body 27 Negative operation electromagnetic brake 28 Balance weight 29 Pulley 30 wires

Claims (3)

(57) [Claims] 1. A structure in which a mold clamping unit in which a mold clamping axis is arranged in a vertical direction and an injection unit in which an injection axis is arranged in a vertical direction are mounted on a machine frame with a mold clamping axis and an injection axis aligned with each other. The mold clamping unit includes an upper platen above the fixed platen horizontally fixed to the machine body frame and a lower platen below the fixed platen. It has a structure in which the molds attached to the upper surface of the fixed platen and the lower surface of the upper platen are opened and closed by a mold clamping mechanism that is connected by a tie bar and connects the lower platen and the fixed platen, and the injection unit is a cylinder assembly above the upper platen. Is placed as the lower part and is attached to the upper platen via a nozzle touch mechanism. The other end of the attached wire is connected to the movable body consisting of the lower platen, the tie bar, the upper platen and the injection unit through the pulley attached to the upper part of the machine frame, and the balance weight is almost balanced with the weight of the movable body. Vertical / vertical injection molding machine featuring 2. The vertical / vertical injection molding machine according to claim 1, wherein the balance weight can be adjusted in weight. 3. Vertical guide plates are fixed on both sides of the upper surface of the upper platen so as to face each other, and a base plate is vertically movably mounted on the guide plates. The injection unit is supported so as to be able to swivel forward, and the moving part of the nozzle touch mechanism is coupled to the base plate.
Vertical / vertical injection molding machine described in.