JPH0153166B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-tube injection molding machine having a large number of heating cylinders, and in particular to a multi-tube injection molding machine equipped with a plurality of pairs of upper and lower molds and a plurality of injection units, and capable of producing a wide variety of molded products. This relates to a multi-tube injection molding machine that can perform molding.

In recent years, in order to comprehensively rationalize production, various production factories have been able to maintain the amount of materials and parts they have by producing only the required quantity at the time required in each process. A production management method that minimizes production is seen as promising. In order to adapt these recent demands for factory management to synthetic resin injection molding operations, intermittent production of a wide variety of molded products in small quantities is necessary, and injection molding machines that can produce a wide variety of molded products in the required quantity at the required time are needed. is required.

However, when changing the molded product, it involves changing the resin material and injection conditions, but if this is done using a single injection unit as in the past, when changing the type of resin material, , a cleaning operation inside the heating tube is required, which usually requires injection of 10 to 20 cleaning shots with new resin, resulting in significant loss of time and waste of material. It also had the disadvantage of being large.

In addition, when changing the resin material, it is generally necessary to change the injection conditions, and among them, problems related to temperature changes are serious, and the temperature changes are performed by changing the setting value of the controller. However, since the heating cylinder has a large heat capacity and a long response time is required for the temperature of the heating cylinder to reach the desired set value, time loss is unavoidable, and furthermore, the control system does not reach a stable state. Another drawback was that it took a much longer time to reach this point.

In view of the problems encountered in molding a wide variety of molded products using the injection molding machine based on the prior art described above, the present invention includes a plurality of injection units set to various molding conditions for a plurality of pairs of upper and lower molds. With this structure, it is an object of the present invention to provide an excellent multi-tube injection molding machine that can eliminate the above-mentioned drawbacks and can injection mold a wide variety of molded products extremely efficiently.

The configuration of the present invention in accordance with the above object selectively moves one pair of the upper and lower molds to the injection position during injection molding operations for many types of molded products,
On the other hand, the heating cylinders of the plurality of injection units arranged above are filled with various resins depending on the desired molded product, and the heating cylinders are maintained at a specific temperature depending on the type of resin. Then, after moving a desired injection unit from among these injection units to the injection position, it is brought into contact with the pair of upper and lower molds selected above, and injection molding is performed to produce different molded products. The gist of this invention is to enable efficient molding of many types of molded products by changing the combination of the mold and injection unit, if necessary.

Next, embodiments of the present invention will be described below based on the drawings.

In Figures 1 to 3, on frame 1,
A rotary table 2 is rotatably mounted, and a mold clamping cylinder 3 is attached to the lower part of the frame 1 and connected to a cross plate 4. The cross plate 4 is connected to an upper mold plate 6 above the rotary table 2 by tie bars 5, and moves the upper mold plate up and down.

The rotary table 2 has one of the tie bars 5 as its rotation center axis, and has a plurality of pairs of molds 7, 7', 7'', . . . lower molds 7 on its upper surface.
a, 7a', 7a'', ... are attached.

On the other hand, an upper mold clamp device 8 is attached to the lower surface of the upper mold plate 6, and clamps the upper mold 7b of the mold 7 with its clamp claws 8a.
or cancel it. That is, the upper mold 7b is detachably fixed to the upper mold plate 6.

A support 10 is erected on the upper mold plate 6, and an upper rotary disk 11 and a lower rotary disk 12 are rotatably provided on the support 10, and a rotary movement device 13 such as an oil motor is installed on the support 10. is connected to. The upper and lower rotary disks 11 and 12 are connected to each other by a plurality of pairs of guide rods 4 and rotate integrally.
As shown in FIG. 4, the guide rod 14 is provided with an injection unit elevating device 15. That is, an elevating cylinder 16 is attached to the guide rod 14 so as to be able to rise and fall freely, and the operating rod 1
The upper end of 7 is fixed to the upper rotary disk 11. Thereby, the upper chamber 18 of the cylinder 16
When hydraulic oil is supplied to the lower chamber 19, the cylinder 16 rises, and when hydraulic oil is supplied to the lower chamber 19, the cylinder 16 descends.

As shown in FIG. 2, an injection unit 20 is attached to the elevating cylinder 16 of the injection unit elevating device 15, and both are moved up and down as one. The injection unit 20 has a heating cylinder 21 at its lower end, and a hopper 22 for supplying material is attached to the upper part of the heating cylinder 21. In the illustrated example, two injection units 20, 20' are installed.

In the above configuration, as shown in FIG. 5A, the upper mold 7b fixed to the lower surface of the upper mold plate 6 by the clamp claws 8a of the upper mold clamp device 8 is connected to the lower mold 7a on the rotary table 2. Closed and clamped, while
The heating cylinder 21 of the injection unit 20 is brought into contact with the upper mold 7b through the upper mold plate 6. In this state, the injection process and the pressure holding/cooling process are performed.

Next, as shown in FIG. 5B, the upper mold plate 6 and the heating cylinder 21 are raised, and the upper mold 7b is moved up to the lower mold 7a.
The mold is opened and the molded product is ejected and taken out.

If the same molded product is to be molded continuously, the fifth
Return to the state shown in Figure A and perform the molding operation.

When changing the combination of the injection unit and the mold in order to mold a different type of molded product, the injection unit 20 is moved to the third mold as shown in FIG. 6A.
Based on the figure, the heating cylinder 21 is separated from the upper mold 7b and the upper mold plate 6 by being raised by the injection unit elevating device 15 as described above.

Next, as shown in FIG. 6B, the upper mold plate 6 is lowered to close the upper mold 7b and the lower mold 7a.

Thereafter, as shown in FIG. 6C, the clamp claw 8a of the upper die clamp device 8 is moved back to release the clamp on the upper die 7b.

Next, as shown in FIG. 6D, the upper mold plate 6 is raised to place the upper mold 7b on the lower mold 7a. Then, the rotary table 2 is rotated to evacuate the mold 7 from the injection position, and the desired mold 7'
enter injection position A.

Subsequently, as shown in FIG. 6E, the upper mold plate 6 is lowered to come into contact with the upper mold 7b' of the mold 7', and the upper mold 7b' is clamped by the clamp claws 8a. Furthermore, the upper and lower rotary disks 11 and 12 are rotated by the rotary drive device 13, and the heating cylinder 21' of the desired injection unit 20' is aligned with the injection position A.

Further, as shown in FIG. 6F, the heating cylinder 21' is lowered together with the injection unit 20' by the injection unit elevating device 15, and is passed through the upper mold plate 6 and into the upper mold 7b'. come into contact with

In this way, a combination of the mold 7' and the injection unit 20' that is different from the original one is realized, and the molding operation is performed with this combination as well.

In the above embodiment, the mold is placed on a rotating table, and the injection unit is also supported by a rotating member. Of course, it is also possible to adopt a configuration that allows selective movement.

Further, the number of molds and the number of injection units are not limited to the illustrated example.

As described above, according to the present invention, in injection molding for molding many types of molded products, a plurality of pairs of upper and lower molds are selectively disposed movably with respect to an injection position, and An upper mold clamping device is attached to the lower surface of an upper mold plate that can be freely raised and lowered above the mold, and a plurality of injection units are further arranged above the upper mold plate to selectively control the injection position. When molded products of different shapes and materials are to be molded, molds with different shapes of die-carving spaces are prepared, and resins of different materials are transferred to each injection unit. All you have to do is fill the heating cylinder, move the desired mold and injection unit to the injection position, connect them, and inject. This eliminates the need to clean the inside of the heating cylinder, which was required in the past. It has the excellent effect of eliminating waste of time and materials, and allowing intermittent injection molding operations of a wide variety of products and small quantities to be carried out extremely efficiently.

In addition, since the heating cylinder of each injection unit is pre-maintained at an appropriate temperature suitable for the resin material filled, injection work can be started immediately after connection with the mold, streamlining the work. It's also effective.

Furthermore, an upper mold clamping device is installed on the upper mold plate to allow the upper mold to be clamped or released, so molds that are not in use can be evacuated with the upper and lower molds closed. There is no risk of damaging the die-cutting space or introducing foreign matter into the die-cutting space during evacuation.

[Brief explanation of drawings]

The figure shows an embodiment of the invention.
The figure is a plan explanatory diagram, the second figure is a front view, and the third figure is a second
XX sectional view in the figure, Figure 4 is an enlarged YY sectional view in Figure 2, Figure 5 A, B is an operation explanatory diagram showing the injection cycle, Figure 6 A, B, C, C, E , F are operation explanatory diagrams showing changes in the mold and injection unit. 2...Rotary table, 6...Upper mold plate, 7...Mold, 8...Upper mold clamp device, 11...Upper turntable, 12...Lower turntable, 14...Guide rod, 15
...Injection unit lifting device, 20...Injection unit, 21...Heating cylinder, A...Injection position.

Claims (1)

[Claims] 1 A plurality of pairs of upper and lower molds 7b and 7a disposed to be selectively movable with respect to the injection position A, and an upper mold plate supported so as to be able to rise and lower above the upper mold 7b at the injection position A. 6, an upper mold clamp device 8 that is attached to the lower surface of the upper mold plate 6 and detachably fixes the upper mold 7b to the upper mold plate 6; and an upper mold clamp device 8 disposed above the upper mold plate 6. A multi-tube injection molding machine comprising a plurality of injection units 20 which are selectively movable with respect to the injection position A and which can be raised and lowered.