JPS6237690Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a reaction injection molding machine that collides and mixes multiple liquid plastic raw materials at high pressure and feeds the mixture into a mold to produce a synthetic resin. This invention relates to a stock solution supply device that automatically replenishes the stock solution into a stock solution storage tank.

Conventionally, in order to replenish liquid plastic (hereinafter referred to as undiluted solution) to the undiluted solution storage tank of this type of molding machine, an operator would open the lid of the undiluted solution inlet of the undiluted solution storage tank and insert the container from the undiluted solution inlet. This was done by pouring the undiluted solution into the container. However, such replenishment has the following problems because the stock solution input port is provided at the upper part of the stock solution storage tank.

First, since the worker directly handles the stock solution, if the stock solution is toxic, the worker is likely to be affected by the toxicity.

Second, when pouring into a container, the stock solution tends to spill out of the stock solution storage tank, contaminating the surrounding area.

Thirdly, the work efficiency is poor because the operator has to be careful about the toxicity of the undiluted solution and the spillage of the undiluted solution during pouring.

This is a problem.

In order to solve this problem, as shown in Fig. 1, an automatic stock solution replenishment device 1 has been developed.
A reaction injection molding machine A is known.

This automatic stock solution replenishment device 1 communicates a stock solution container 4 with a stock solution storage tank 2 via a communication pipe 3.
Furthermore, a supply pump 5 is arranged in the middle of the communication pipe 3. In addition, this automatic replenishment device 1
As the stock solution in the stock solution storage tank 2 decreases,
By driving the supply pump 5, the stock solution is supplied from the stock solution container 4 into the stock solution storage tank 2. Although such an automatic replenishing device 1 has solved the above-described problems that occurred when replenishing the stock solution by the operator, the following problems still remain.

In other words, a set of supply pumps necessary for replenishing the stock solution must be newly installed as ancillary equipment to the reaction injection molding machine, which increases the size of the equipment and
The problem was an increase in equipment costs.

This idea was made in view of the above-mentioned circumstances, and it is possible to switch between a communication pipe that communicates between the stock solution pressure feeding cylinder and the mixing head, and a communication pipe that communicates between the stock solution storage tank and the stock solution pressure delivery cylinder. A device for supplying the concentrated solution to the concentrated solution storage tank by arranging a valve and communicating the concentrated solution container with the concentrated solution pressure-feeding cylinder through a communication pipe having a switching valve, and by switching the switching operation of the switching valve between the concentrated solution pressure-feeding cylinder and the concentrated solution container. By operating it as a reaction injection molding machine, it is possible to eliminate conventional defects and problems, improve safety and workability, and do not cause enlargement of equipment or increase in equipment costs. The purpose of this invention is to provide a stock solution replenishment device.

This invention will be explained in detail below based on an embodiment shown in FIG. In this example, a two-liquid C/D mixing type reaction injection molding machine is shown, and since the pair of devices that pump both liquids individually have the same configuration, they will not be used in the following explanation. Only one configuration will be explained, and the other configuration will be given the same reference numerals and detailed explanation thereof will be omitted.

In the drawing, the symbol B indicates a two-component mixing type reaction injection molding machine, and this reaction injection molding machine B includes a stock solution storage tank for temporarily storing stock solution, and a communication pipe 7 connected to the stock solution storage tank 6. A stock solution container 10 is connected to the pressure-feeding cylinder 8 through a communication pipe 9, and a stock solution container 10 is connected to the pressure-feeding cylinder 8 through a communication pipe 11. The mixing head 13 is connected to the stock solution storage tank 6. The communication pipes 7, 9, 11 each have switching valves 14, 1.
5 and 16 are arranged, and these switching valves 1
4, 15, 16, the communication pipes 7, 9,
11 are opened and closed. A driving device 19 that is composed of a solenoid valve 17 and a double-acting cylinder 18 and is operated by hydraulic pressure is connected to the pressure-feeding cylinder 8, and the pressure-feeding cylinder 8 is driven by this drive device 19. It is done like this. Furthermore, in the mixing head 13,
A driving device 22 consisting of a solenoid valve 20 and a double-acting cylinder 21 and operated by hydraulic pressure is connected, and the injection operation of the mixing head 13 is performed by this driving device 22. There is. Although not shown, the mixing head 13 is connected to a mold into which the two stock solutions C and D mixed in the mixing head 13 are injected.

Next, the operation of this invention will be explained.

First, the operation for producing synthetic resin will be explained. Prior to driving the pressure-feeding cylinder 8, the switching valve 14 and the switching valve 16 are switched to the open state,
The stock solution storage tank 6, the pressure cylinder 8 and the mixing head 13 are connected to each other. From this, by operating the drive device 19, the piston of the pressure-feeding cylinder 8 is moved in the suction direction (in the direction of the dashed line arrow in the figure), and the stock solution C in the stock solution storage tank 6 is sucked into the pressure-feeding cylinder 8, and then the switching By switching the valve 14 to the closed state and operating the drive device 19, the piston of the pressure-feeding cylinder 8 is moved in the discharge direction (in the direction of the solid line arrow in the figure), and the stock solution C in the pressure-feeding cylinder 8 is transferred to the mixing tube 13. to pump. On the other hand, since the other stock solution D is also pumped to the mixing head 13 in the same way as the stock solution C, if the drive device 22 is operated to operate the mixing head 13, the above Two stock solutions C and D
can be collided and mixed by the pressure of the pressure cylinders 8, 8, and then injected into the mold. In this process of collision mixing and injection, two stock solutions C and D
A chemical reaction is caused to produce a synthetic resin.

Next, the operation for replenishing the stock solution C from the stock solution container 10 to the stock solution storage tank 6 will be explained.

Prior to driving the pressure-feeding cylinder 8, the switching valve 14 and the switching valve 16 are switched to a closed state, and the switching valve 15 is switched to an open state to cut off communication between the pressure-feeding cylinder 8, the stock solution storage tank 6, and the mixing head 13. At the same time, the pressure feeding cylinder 8 and the stock solution container 10
communicate with. From this, by operating the drive device 19, the piston of the pressure-feeding cylinder 8 is moved in the suction direction (the direction of the one-dot chain arrow in the figure), and the stock solution C in the stock solution container 10 is sucked into the pressure-feeding cylinder 8, and then , the switching valve 14 is switched to the open state and the switching valve 15 is switched to the closed state, and the driving device 19 is operated to move the piston of the pressure-feeding cylinder 8 in the discharge direction (in the direction of the solid line arrow in the figure) to perform pressure-feeding. The stock solution C in the cylinder 8 is pumped into the stock solution storage tank 6. By continuously performing such operations, the stock solution C is replenished from the stock solution container 10 to the stock solution storage tank 6, as shown by the two-dot chain arrow in the figure. Further, this kind of replenishment also applies to the stock solution D.

The flow of the stock solutions C and D indicated by broken line arrows in FIG. 2 is such that when the injection operation by the mixing head 13 is in a paused state, the stock solutions C and D pumped to the mixing head 13 are transferred to the stock solution storage tank 6. , 6.

In the above embodiment, although the solenoid valve 17 is shown as a single one, there are two solenoid valves corresponding to the double-acting cylinders 18, 18.
You may also provide one. In addition, drive devices 19 and 22
Although an example in which the switching valve is operated by hydraulic pressure has been described, the present invention is not limited to this, and various structures of the switching valve can be adopted as long as they open and close the communication pipe.

As described above, a switching valve is disposed in each of the communication pipe that communicates between the raw liquid pressure feeding cylinder and the mixing head, and the communication pipe that communicates between the raw liquid storage tank and the raw liquid pressure feeding cylinder. According to this invention, in which the stock solution container is connected to the stock solution container through a communication pipe having a switching valve, the stock solution pumping cylinder can be used for stock solution replenishment by switching the switching valve. There is no need to install a new supply pump for this purpose, so safety and workability can be improved without increasing equipment costs.Also, since only a switching valve is installed, it is possible to reduce the size of equipment. can be prevented.
Furthermore, if the switching operation of the switching valve is electrically controlled in synchronization with the operation of the raw liquid pumping cylinder, the replenishment performance can be further improved.

This invention can thus provide a stock solution replenishment device for a reaction injection molding machine that can achieve various practical effects.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional device, and FIG. 2 is an overall device diagram showing an embodiment of this invention. 6... Stock solution storage tank, 7, 9, 11... Communication pipe, 8... Pressure feeding cylinder, 10... Stock solution container, 1
3...Mixing head, 14, 15, 16...Switching valve, B...Reaction injection molding machine.

Claims (1)

[Scope of utility model registration request] a plurality of stock solution storage tanks; a plurality of stock solution pressure-feeding cylinders that are individually connected to each of the stock solution storage tanks;
In a reaction injection molding machine having a single mixing head with which the stock solution pressure feeding cylinder is communicated, a communication pipe that communicates between the stock solution pressure feeding cylinder and the mixing head;
A switching valve is disposed in each of the communication pipes that communicate between the stock solution storage tank and the stock solution pressure-feeding cylinder, and the stock solution container is communicated with the stock solution pressure-feeding cylinder through the communication pipe having the switching valve. A stock solution replenishment device for reaction injection molding machines.