JPH0615032Y2 - Vacuum cooling device for foam molding dies - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a foam molding mold for efficiently removing water on the surface of a molded product by evacuating the steam chamber of the foam molding mold. The present invention relates to a vacuum cooling device.

[Conventional technology]

When molding is performed using a foamed synthetic resin material such as foamed polystyrene, a mold as shown in FIG. 3 is used.

That is, the foam molding mold is composed of a concave mold a and a convex mold b, and forms a molding space c when both molds are closed.

Both molds are provided with a steam supply pipe d for heating, a cooling water pipe e for cooling, a drain pipe f, an exhaust port g for exhaust, and the like.

At least one of the molds is provided with a filler h for filling the raw material that communicates with the molding space c, and a vent hole for venting the raw material filling mold is provided at a position corresponding to the molding space c of both molds a and b. i is provided.

In addition to this, an eject pin or the like for taking out the molded product is provided, but it is not shown here.

When performing foam molding using such a mold, after the mold is closed, the raw material beads of the foam synthetic resin are filled from the filler h,
Steam is supplied from the steam supply pipe d for heating and foaming, and then water is injected from the cooling water pipe e to perform cooling.

At this time, the water that has entered through the ventilation holes i adheres to the surface of the molded product in the molding space c and leaks the molded product.

Therefore, after draining water from the drain pipe f, vacuum suction is performed from the exhaust port g to remove water.

As shown in FIG. 4, a condenser j is provided between the exhaust port g of the die and the vacuum pump k, and the water vapor discharged from the vapor chamber of the die is condensed into moisture in the condenser j. Drained.

As the condenser j, for example, a water-cooled multi-tube condenser, a barometric condenser or a spray condenser is used.

[Problems to be solved by the device]

In the mold cooling device as described above, the condensation of the water vapor by the condenser j is not sufficient, and the water vapor is sucked into the vacuum pump k, which lowers the exhaust capability of the vacuum pump.

From this, the degree of vacuum in the steam chamber and exhaust pipe of the mold becomes low, the removal of moisture adhering to the surface of the molded product becomes insufficient, and sufficient time is taken for packing to dry the molded product. Therefore, the molding cycle time becomes long and the work efficiency becomes poor.

In view of the above problems, the present invention efficiently performs suction by a vacuum pump, thereby efficiently removing water adhering to the surface of the molded product in the molding space to improve work efficiency. The purpose is to provide a cooling device.

[Means for Solving the Problems]

The present invention provides a vacuum pump for vacuuming a vapor chamber of a foam molding die, and an exhaust pipe having at least two paths between an exhaust port of the vapor chamber of the foam molding die and the vacuum pump. A switching valve for selecting a path of the exhaust pipe, a trap for vapor condensation provided in each path of the exhaust pipe, and a refrigerant to which a refrigerant for cooling the inside of the trap to freeze condensed water is supplied. Vacuum of a mold for foam molding having a pipe, a pipe for hot water to which hot water for melting frozen water in the trap is fed, and a switching valve for selecting the pipe for refrigerant and the pipe for hot water. It constitutes a cooling device.

[Action]

The vacuum cooling device for the foam molding die according to the present invention is configured as described above, and any one of the plurality of paths of the exhaust pipe can be used to evacuate the chamber of the foam molding die after the foam molding is completed. This is selected by a switching valve, and the refrigerant is supplied to the refrigerant pipe arranged in the trap on the selected path to condense the steam from the steam chamber into moisture and freeze it.

At the time of evacuation of the foam molding die in the next foam molding process, another path of the exhaust pipe is selected, and the refrigerant is supplied to the refrigerant pipe of the trap in this path, and the steam chamber is discharged. Condenses the vapor of water into water and freezes it.

At this time, hot water is fed to the hot water pipe of the trap used in the previous molding step to melt the frozen water and drain it.

Repeat this process to increase the efficiency of the vacuum pump,
It shortens the molding cycle time.

〔Example〕

 The details of the present invention will be described based on illustrated embodiments.

FIG. 1 is a simplified block diagram for explaining an embodiment of a vacuum cooling device for a foam molding die according to the present invention.

In FIG. 1, reference numeral 1 denotes a foam molding die including a concave die 2 and a convex die 3, and the concave die 2 and the convex die 3 each have a steam chamber 4 to which heated steam is supplied. An exhaust port 5 for vacuum suction is provided in the steam chamber 4.

Reference numeral 6 is a vacuum pump for evacuating the vapor chamber 4 of the foam molding die 1.

The exhaust pipe 7 from the exhaust port 5 to the vacuum pump 6 is branched into at least two or more paths, and the illustrated one is branched into two paths by the switching valves 9 and 10.

A trap 8 for vapor condensation is provided in each path of the exhaust pipe 7, and the vapor discharged from the vapor chamber 4 is condensed into moisture.

As the switching valves 9 and 10, for example, a three-way electromagnetic valve or the like is used, which is controlled by a computer or the like, and selectively introduces the vapor from the vapor chamber 4 into the condensation trap 81 or 82.

FIG. 2 is a schematic diagram for explaining the refrigerant / hot water pipes provided in the trap.

Reference numeral 11 is a refrigerant pipe for supplying a refrigerant for freezing the water condensed in the trap 8. As the refrigerant to be supplied, ammonia or another one is adopted.

Reference numeral 12 is a hot water pipe for supplying hot water for melting the water frozen in the trap 8.

The refrigerant pipe 11 and the hot water pipe 12 are switched by the switching valves 13 and 14, and the refrigerant or the hot water is selectively introduced into the trap 8.

As shown in FIG. 2, when the trap 81 and the trap 82 are both configured, the switching valve 131,
132 is provided, and switching valves 141 and 142 are provided on the discharge side.

Next, the operation of the vacuum cooling device for the foam molding die of the present invention will be described.

After the heating / foaming and cooling steps by the foam molding machine are completed, the switching valves 9 and 10 are used to trap the condensation trap 8.
On the 81 side, the vacuum pump 6 evacuates.

At this time, the refrigerant is introduced into the trap 81 by setting the switching valves 131 and 141 to the refrigerant pipe 11 side.

The vapor introduced from the exhaust pipe 7 into the trap 81 is condensed into water and is cooled by the refrigerant to be trapped in the trap 81.
Freezing inside.

As a result, vapor is not sucked into the vacuum pump 6, vacuuming can be performed efficiently, and water adhering to the surface of the molded product can be removed efficiently.

In the next molding step, the switching valves 9 and 10 are switched to the trap 82 side, and the steam from the steam chamber 4 is introduced into the trap 82.

At this time, the refrigerant is introduced into the trap 82 with the switching valves 132 and 142 on the refrigerant pipe 11 side.

Similarly to the above, the steam introduced from the steam chamber 4 into the trap 82 is condensed into moisture and frozen due to cooling by the refrigerant, and is not discharged to the vacuum pump 6 side.

At the same time, the switching valves 131 and 141 are set to the hot water pipe 12 side, hot water is introduced into the trap 81, and the water in the trap 81 frozen in the previous molding step is melted and discharged.

By repeating this process, the vacuum pump 6 can be used efficiently and the molding cycle time can be shortened.

It is possible to provide two or more paths for the exhaust pipe 7,
Further, it is possible to separately provide the condensation traps 8 corresponding to the concave mold 2 and the convex mold 3.

[Effect of device]

The vacuum cooling device for a foam molding die according to the present invention has the above-described configuration, and is provided with a trap for condensation provided in the middle of the exhaust pipe when the vacuum chamber is evacuated by the vacuum pump. The vapor is condensed into water by means of, and further cooled by the refrigerant to freeze the water, and the vacuum pump is efficiently sucked.

This effectively removes the moisture adhering to the surface of the molded product, shortens the molding cycle time, and improves the work efficiency.

Further, since the exhaust pipe is composed of a plurality of paths and a trap for vapor condensation is provided in each of the paths, efficient vacuum suction can be performed by alternately selecting and using the paths.

Also, if hot water is sent from the hot water pipe to the condensation trap in the unused path, and the frozen water is thawed and discharged, it can be used in the next step, improving work efficiency. is there.

[Brief description of drawings]

FIG. 1 is a simplified block diagram for explaining an embodiment of a vacuum cooling device for a foam molding die according to the present invention, FIG. 2 is a schematic diagram for explaining a refrigerant / hot water pipe used in the present invention, and FIG. 3 is foam molding. FIG. 4 is a schematic cross-sectional view of a conventional example, and FIG. 1: Mold for foam molding, 2: Mold for concave mold, 3: Mold for convex mold, 4: Steam chamber, 5: Exhaust port, 6: Vacuum pump, 7: Exhaust pipe, 8: Trap for condensation, 9: Switching Valve, 10: switching valve, 11: refrigerant piping, 12: hot water piping, 13: switching valve, 14: switching valve.

Claims (1)

[Scope of utility model registration request] 1. A vacuum pump for evacuating the vapor chamber of a foam molding die, and an exhaust pipe having at least two or more paths between an exhaust port of the vapor chamber of the foam molding die and the vacuum pump. A switching valve for selecting a path of the exhaust pipe, a trap for vapor condensation provided in each path of the exhaust pipe, and a refrigerant for cooling the inside of the trap to freeze condensed water A foaming mold having a refrigerant pipe, a hot water pipe for supplying hot water for melting the water frozen in the trap, and a switching valve for selecting the refrigerant pipe and the hot water pipe. Vacuum cooling device.