JPH01214419A - Release method and device for injection molding machine - Google Patents

Abstract

PURPOSE:To enhance workability of releasing and shorten release time by lowering and lifting an intermediate mold to a desired height when a space between a top force and a bottom force is stretched up and down at the time of mold opening. CONSTITUTION:As a bottom force 10 is lowered, an intermediate mold 12, the weight of which is supported by the bottom force 10, is also lowered together with the bottom force 10, and as a product 21 in a cavity of the intermediate mold 12 and sprue flashes 22 carried on an intermediate mold 11 are connected with flashes of a narrow gate section, the intermediate mold 11 is lowered together with the intermediate mold 12. As said molding process comes close to end, the intermediate mold 11 reaches the lower end of a guide shaft 13 and not to be able to rise or lower, and subsequently the intermediate mold 12 is not able to rise or lower because of an ejector 17, followed lastly by the bottom force 10 reaching the lower limit to stop. The product 21 and sprue flashes 22 are separated forcibly in said lowering process, and the product 21 is separated from the bottom force 10 constituting part of the cavity. Then, the intermediate mold 11 is lifted up, and the product 21 is released from the intermediate mold 12.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a mold release method and device for an injection molding machine, and particularly to an injection molding machine having a structure in which a middle mold is provided between an upper mold and a lower mold. The present invention relates to a mold release method and a mold release device.

[Conventional technology]

-C, a vertical injection molding machine such as a C-type frame or tie-bar type frame is equipped with an injection cylinder above the upper mold and a mold clamping cylinder below the lower mold, and the mold is lowered by the mold clamping cylinder. After the mold is raised and clamped, the molding material is injected into the cavity by an injection cylinder, and after molding is completed, the lower mold is lowered by the mold clamping cylinder to release the product from the cavity.

This type of injection molding machine is not only a molding machine equipped with an injection cylinder, but also a press machine equipped with a mold clamping cylinder, which is an important element in the mechanical properties of a press machine. In order to maintain the precision between the plates, the distance between the plates (that is, the distance in the two downward directions formed between the upper die and the lower die) cannot be made too large.

[Problem to be solved by the invention]

However, in such conventional products, when a middle mold is provided between the upper mold and the lower mold, mold release work is performed between the upper mold and the middle mold and between the middle mold and the lower mold, respectively. When the mold is opened, the middle mold is positioned at an intermediate height between the upper mold and the lower mold, so that the mold release work can be carried out above and below the middle mold, but on the other hand, both of them require less space. Since sufficient amount of water cannot be removed, there are problems in that workability is poor and demolding takes time.

However, as shown in FIG. 4, for example, a mold-drawing type injection molding machine in which the mold and mold clamping cylinder 40 are pulled out to the front while the injection cylinder 39 remains on the main body frame 38 side when the mold is opened. If so, a sufficient space is secured for performing mold release work, but such a mold-drawing type injection molding machine has the problem of high cost.

It is an object of the present invention to provide a mold release method for an injection molding machine that can solve the problems of the conventional methods as described above, improve the workability of mold release work, and shorten the mold release time. It is purposeful.

Another object of the present invention is to provide a mold release device for an injection molding machine which is a device for carrying out the mold release method as described above, and which is cheaper in cost than a mold drawer type. .

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention provides an injection molding machine having a middle mold between an upper mold and a lower mold, in which the gap between the upper mold and the lower mold increases vertically as the mold opens. when the medium size is lowered or raised to a desired height,
Thereby, the mold release operation is performed in a wide space formed between the upper mold and the middle mold or between the middle mold and the lower mold.

Further, the present invention provides an injection molding machine having a middle mold between an upper mold and a lower mold, which is provided with a spring balancer that allows the middle mold to stand still at an arbitrary height when the mold is opened.

[Effect]

By adopting the above-mentioned means, this invention secures a wide space between the upper mold and the middle mold by lowering the middle mold when opening the mold, and secures a large space between the middle mold and the lower mold by raising the middle mold. A large space will be secured between them.

In addition, in this invention, even when the middle mold is lowered or raised when the mold is opened, the middle mold remains stationary at an arbitrary height due to the action of the spring balancer.

〔Example〕

Embodiments of the invention shown in the drawings will be described below.

1 to 3 show an embodiment of a mold release device for carrying out the mold release method for an injection molding machine according to the present invention. Heat insulation board 2
An upper die 5 is fixed by a die fixing hook 4 via an upper heating plate 3, and a lower die 10 is fixed by a die fixing hook 9 via a heat insulating plate 7 and an upper heating plate 8 to the upper surface of the lower die plate 6. A middle mold 11 and a middle mold 12 are arranged vertically between the two.

The medium die 11 has four pieces permanently installed on the upper die plate 1 (
It is guided so as to be able to rise and fall vertically along a guide shaft 13 (see Figs. 2 and 3), and is tensioned between an arm 14 protruding from both sides and an arm 15 protruding from the upper guide plate 1. A spring balancer 16 provided allows the mold to stand still at an arbitrary height when the mold is opened.

The medium 12 has four pieces (
By the ejector 17 (see FIGS. 2 and 3),
It is designed so that it can be lifted up easily from the lower mold 10 when the mold is opened.

In FIGS. 2 and 3, 18 is a main body frame of the injection molding machine, 19 is an injection cylinder, and 20 is a mold clamping cylinder.

Next, the operation of the above will be explained.

First, during mold clamping, the mold clamping cylinder 20 is operated to raise the lower mold 10, and as a result, the upper mold 5 and the middle mold 11, the middle mold 11 and the middle mold 12, and the middle mold 12 With both the mold and the lower mold 10 in close contact with each other, the injection cylinder 19 is operated to inject the molding material into the cavity,
Let it form.

Next, after the molding is completed, the mold clamping cylinder 20 is operated in the opposite direction.

Then, the lower mold 10 descends, and the middle mold 12 whose weight is supported by the lower mold 10 also descends together with the lower mold 1O, and the product 21 in the cavity of the middle mold 12 and the sprue burr 22 supported by the middle mold 11 are removed. are connected by a narrow gate section climber, so the middle mold 11 also descends together with the middle mold 12.

Then, as the end of this descending process approaches, Figure 1 (b
), first, the medium 11 is attached to the guide shaft 13.
reaches the lower end and cannot be lowered any further, then the middle mold 12 cannot be lowered any further by the ejector 17, and finally the lower mold 10 reaches the lower limit position and stops.

That is, in this lowering step, the product 21 and the sprue burr 22 are forcibly separated, and the product 21 is forcibly separated from the lower mold 10 forming a part of the cavity.

In this state, the operator removes the sprue burr 22 and then lifts the medium mold 11 upward as shown in FIG. 1(C).

At this time, the middle mold 11 is supported in a balanced state by the spring balancer 16, so it can be lifted with a slight force, and if the hand is released at the desired height, it will come to rest at that height.

Therefore, the operator releases the product 21 from the middle mold 12 in this state.

In the above embodiment, two middle molds 11 and 12 are arranged between the upper mold 5 and the lower mold 10, but the present invention is not limited to this (the number of middle molds can be arbitrarily selected). Of course, it can be set to

〔Effect of the invention〕

With this invention configured as described above, by lowering the middle mold when opening the mold, a wide space can be secured between the upper mold and the middle mold, and therefore, this space can be used to perform the necessary mold release work. It can be done efficiently and quickly, and by raising the middle mold, a large space can be secured between the middle mold and the lower mold, so this space can be used to perform the necessary mold release work efficiently and quickly. Therefore, it has the advantage of improving the workability of the mold release operation and shortening the mold release time.

Also, compared to the conventional mold drawer type, this invention
This has the effect of reducing costs.

[Brief explanation of the drawing]

1 to 3 show an embodiment of a mold release device for carrying out the mold release method for an injection molding machine according to the present invention, and FIG.
a) is a partially cutaway front view when the mold is closed, FIG. 1(b) is a partially cutaway front view when the mold is opened, and FIG. 1(C) is a part showing another state when the mold is opened. FIG. 2 is a front view of the entire injection molding machine, FIG. 3 is a side view of the one shown in FIG. 2, and FIG. 4 is a side view of an example of the conventional injection molding machine. 1... Upper die plate 2... Insulation plate 3... Upper heating plate 4.9... Mold fixing hook 5... Upper mold 6...Lower die plate 7...Insulation plate 8...Upper heating plate 10...Lower die 11.12...Medium die 13. ...Guide shaft 14.15 ...Arm 16 ...Spring balancer 17 ...Ejector 18.38 ...Body frame 19.39 ... ...Injection cylinder 20.40...Mold clamping cylinder

Claims (2)

[Claims] (1) Medium mold (11) between upper mold (5) and lower mold (10)
In the injection molding machine equipped with (12), when the gap between the upper mold (5) and the lower mold (10) increases vertically as the mold opens, the middle mold (11) and (12) are moved to the desired position. lowering or raising the height, thereby separating the upper mold (5) and the middle mold (11) in a wide space formed between the middle mold (12) and the lower mold (10). A mold release method characterized by performing mold work. (2) A middle mold (11) between the upper mold (5) and the lower mold (10)
(12) In the injection molding machine equipped with the medium mold (11),
) at a desired height when the mold is opened.