JPH0133317Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a cleaning device for a mold section of a plastic container molding machine. A plastic container forming machine heats and melts synthetic materials and forms them into containers.
A machine that performs each step of filling and sealing the container with one machine.

Conventionally, in a plastic container molding machine, a mold section for molding a heated and melted synthetic material into a container is provided with a large number of pores in order to hold a flexible material and container in the mold section, and vacuum air is inserted into the mold section. However, if the container ruptures when the filling is injected into the container, the filling will be sucked into the pores and the filling will solidify over time. It is necessary to immediately clean the vacuum air circuit and the vacuum air circuit, but this has the disadvantage that cleaning is difficult and takes a lot of time.

The present invention eliminates this drawback and provides a plastic container molding machine that can clean the vacuum air circuit in a short time when necessary without interfering with container molding operations by appropriately combining the vacuum air circuit with a cleaning circuit. An object of the present invention is to provide a cleaning device for a mold part. Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a granular synthetic material is charged into a hopper 1 shown in FIG. Sterilized compressed air is supplied to the hollow part of the parison 3 from an air supply port 4. A mold part 5 is provided below the parison head 2, and the parison 3
is extruded to a certain length, it is held in place,
The dies 6, 6 seal the lower end of the parison 3, and the upper part of the dies 6, 6 and its retainer 7, 7.
The upper part of parison 3 is held by die 6,
Vacuum air is supplied to the parison 6 and the retainers 7, 7 as will be described later, to ensure that the flexible parison 3 is retained. The parison 3 held by the mold part 5 is slightly expanded by the supplied compressed air, and then the upper part is cut by the cutter 8, and at the same time, the parison 3 is moved below the mandrel device 9 as shown in Figure b. While moving, the parison 3 contracts slightly to release air to prevent outside air from entering, and below the mandrel device 9, the opening of the parison 3 is surrounded by an atmosphere of sterilized air.

A molding mandrel 10 is lowered from the mandrel device 9 and inserted through the opening of the parison 3, and the parison 3 is airtightly held between its lower end and the upper parts of the dies 6, 6. When sterilized compressed air is supplied to the molding mandrel 10 from the supply/discharge port 11 and blown from the lower end thereof, the parison 3 expands along the inner shape of the dies 6 and is molded into the container 12.

Subsequently, when the filling mandrel 13 installed concentrically with the forming mandrel 10 is lowered and a valve (not shown) at its lower end is opened, a certain amount of filling material is pushed out from the tank 14 by the metering cylinder device 15. , filling mandrel 1 via hose 16
3 and injected into the container 12. The air in the container 12 is pushed out and escapes from the supply/discharge port 11. When the filling is completed, the filling mandrel 13 closes the valve and rises, and rises together with the forming mandrel 10. The opening of the container 12 is clamped and sealed by sealing dies 17, 17 to complete the product.

The mold part 5 is opened and the product is taken out, and
The mold part 5 moves below the parison head 2.

In FIG. 2, the structure of the mold part 5 and its circuit are shown. Die 6 of mold part 5, sealing die 17
Each of the holders 7 and 7 has a hollow structure, and a large number of pores 18 are provided between the hollow parts and the surface facing the parison 3 or the container 12. The hollow part 6a of the die 6, the hollow part 17a of the sealing die 17, and the hollow part 7a of the retainer 7 are provided with pneumatic switching valves 19a, 19b, 19c and 1 for supplying vacuum air or cleaning liquid.
It is connected to a vacuum pump 20 and a cleaning fluid source 21 via 9d.

Pneumatic switching valves 19a, 19b, 19c and 19d
The cylinder chambers have corresponding solenoid valves 22a and 22, respectively.
It is connected to a compressed air source 23 via b, 22c and 22d. The pneumatic switching valve 19 is divided into, in order from top to bottom, a cylinder chamber housing a piston 24, an upper chamber 25, a valve chamber 26, and a lower chamber 27.
A contained valve 28 is connected to the piston 24. When a signal is sent to the solenoid valve 22 to switch, compressed air is supplied to the pneumatic switching valve 19, the valve 28 rises together with the piston 24, the space between the upper chamber 25 and the valve chamber 26 is closed, and the space between the valve chamber 26 and the lower chamber 27 is closed. When the solenoid valve 22 is switched to open and the signal to the electromagnetic valve 22 is turned off, the valve 28 is lowered together with the piston 24 by the biasing force of the spring, and the switch is reversely switched. The hollow part 6a of the die 6 is a pneumatic switching valve 19c.
The hollow portion 17a of the sealing die 17 and the hollow portion 7a of the retainer 7 are connected to a lower chamber 27d and an upper chamber 25d of the pneumatic switching valve 19d, respectively. The valve chamber 26d of the pneumatic switching valve 19d and the lower chamber 27c of the pneumatic switching valve 19c are connected to the upper chamber 25b of the pneumatic switching valve 19b.
The valve chambers 26a, 26b of the valve chambers 9b and 19a are connected to each other, and the lower chambers 27a, 27b are connected to the cleaning liquid source 21.
has been contacted. Upper chamber 2 of pneumatic switching valve 19a
5a is a vacuum pump 20 via a tank 29
tank 29 when the cleaning liquid is aspirated.
This prevents the liquid from accumulating in the vacuum pump 20 and being sucked into the vacuum pump 20. The tank 29 is provided with a control valve 30 and is discharged when the liquid reaches a certain amount or more.

Next, we will discuss the effect. In FIG. 2, when the plastic container forming machine is in operation, the vacuum pump 20 is started, the cleaning liquid source 21 and the compressed air source 2 are activated.
3 is in a state where cleaning liquid (usually hot water is used) and compressed air can be supplied, respectively. When supplying vacuum air to the mold part 5, pneumatic switching valves 19a, 1
9b is in the state shown in the figure, and the piston 24 is lowered. In other words, vacuum air is pneumatic switching valve 1.
From the upper chamber 25a and valve chamber 26a of pneumatic switching valve 19b, the lower chamber 27c of pneumatic switching valve 19c and the valve chamber 26 of 19d pass through the upper chamber 26b and upper chamber 25b of pneumatic switching valve 19b.
d. When the retainer 7 holds the parison 3, the piston 24 of the pneumatic switching valve 19d
d is descending, from the valve chamber 26d to the upper chamber 25d.
Vacuum air is supplied to the hollow part 7a of the retainer 7 through it. When the parison 3 is molded into the container 12, a signal is sent to the solenoid valve 22c, the piston 24c of the pneumatic switching valve 19c is raised to switch the valve 28c, and vacuum air is supplied from the lower chamber 27c and the valve chamber 26c to the hollow of the die 6. The container 12 is filled with the filling material and then restored. When the sealing die 17 seals the opening of the container 12, it sends a signal to the solenoid valve 22d and compressed air is transferred to the pneumatic switching valve 19d.
The feed piston 24d is raised and the valve 28d is switched to supply vacuum air to the hollow part 17a of the sealing die 17 and stop the supply to the hollow part 7a of the retainer 7.

When supplying the cleaning liquid to the mold part 5, the solenoid valve 2
2a, compressed air is sent to the pneumatic switching valve 19a, the piston 24a is raised, the valve 28a is switched, the supply of vacuum air is stopped to the valve chamber 26a, and the cleaning liquid is supplied. , 19d. After the cleaning is completed, the pneumatic switching valve 19a is restored, vacuum air is supplied to each part, and the cleaning liquid remaining in the circuits is collected in the tank 29. In addition, if the container 12 breaks in the mold part 5 and the filling is sucked in, the filling will be transferred to the tank 29.
After that, immediately perform the above operation.
In order to prevent the filling accumulated in the tank 29 from solidifying, the signal to the solenoid valve 22a is turned off, and the solenoid valve 22
b, sends compressed air to the pneumatic switching valve 19b, raises the piston 24b, switches the valve 28b, sends the cleaning liquid to the tank 29, and controls the control valve 30.
sends a signal to open tank 2, drains the cleaning solution, and drains tank 2.
Wash 9.

As is clear from the above description, according to the present invention, by operating the electromagnetic valve and switching the pneumatic switching valve by electric signals, the mold section can smoothly form, fill, and seal the container, and It has great practical effects and advantages, such as being able to clean the mold part and the circuit as needed, and improving productivity because the operation is simple and cleaning can be done in a short time.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the structure and operation of a plastic container molding machine, and FIG. 2 is a longitudinal sectional view of a mold section and a necessary circuit diagram according to an embodiment. 1 is a hopper, 2 is a parison head, 3 is a parison, 4 is an air inlet, 5 is a mold part, 6 is a die, 7 is a retainer, 8 is a cutter, 9 is a mandrel device, 10 is a molding mandrel, 11 is a Supply/discharge port, 12 is a container,
13 is a filling mandrel, 14 is a tank, 15 is a measuring cylinder device, 16 is a hose, 17 is a sealing die, 18 is a pore, 19 is a pneumatic switching valve, 20 is a vacuum pump, 21 is a cleaning liquid source, 22 is a solenoid valve,
23 is a compressed air source, 24 is a piston, 25 is an upper chamber, 26 is a valve chamber, 27 is a lower chamber, 28 is a valve, 29
is a tank, and 30 is a control valve.

Claims (1)

[Scope of utility model registration request] In the mold section of a plastic container molding machine, a hollow section is provided in the mold section that communicates with the surface of the mold section in contact with the parison through a number of pores, and between the hollow section and the vacuum pump and the cleaning liquid source. A cleaning device for a mold section of a plastic container molding machine, characterized in that a circuit having a plurality of pneumatic switching valves for freely switching and connecting the hollow section to a vacuum pump and a cleaning liquid source is provided.