JPH0727148Y2 - Cooling device for injection molding machine - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a cooling device for an injection molding machine. More specifically, it can prevent a backflow phenomenon that occurs when a valve is forgotten to be tightened in a cooling water branch pipe provided for each system. The present invention relates to a cooling device.

"Prior Art" FIG. 3 shows an example of a cooling device attached to a conventional injection molding machine.

First, the injection molding machine will be briefly described. The injection molding machine shown here is one in which a mold clamping device 2 and an injection device 3 are provided on a pedestal 1, and a fixed platen 4 constituting the mold clamping device 2 is provided.
The molds 6 and 7 between the movable plate 5 and the movable plate 5,
The injection device 3 is slid to the left in the figure, and the nozzle 3a at the end of the heating cylinder is pressed against the central hole (not shown) of the fixed platen 4, and the molten resin is injected from the nozzle 3a and between the molds 6 and 7. Molding is performed in the formed cavity.

Further, the injection molding machine is provided with the following cooling device C. That is, the supply-side header 10 and the return-side header 11 are arranged in the gantry 1, and branching from the headers 10 and 11 through branch pipes 12a to 12d connected to respective parts in the injection molding machine that require cooling. Cooling water is supplied for each system.

More specifically, the cooling water supplied to the supply-side header 10 is divided into the branch pipes 12a to 12d, passes through the flow regulating ball valve 13 and the flow meter 14, and is cooled by the molds 6, 7 or the injection. It is sent to the lower hopper 3b of the device 3. The molds 6 and 7 are cooled in order to solidify the molten resin at an early stage, and the lower part of the hopper 3b is cooled so that the resin material fed from the hopper is not melted in the lower part of the hopper and the vicinity of the front nozzle is This is for melting at the point of reaching.

After that, the cooling water is collected from the branch pipes 12e to 12h on the return side through the ball valve 15 to the header 11 on the return side, and is discharged to the outside from there. Further, it is sent from the return side header 11 to the heat exchanger, where it is appropriately cooled, then pressure-fed by the pump, and supplied again to the supply side header 10.

[Problems to be solved by the invention] By the way, in the cooling device C of the injection molding machine described above, the cooling system is not always completely used, and the branch pipes 12d and 12h not used are on the supply side and the return side. The ball valves 13 and 15 are closed. At that time, the supply side ball valve 13 is relatively rarely forgotten to be closed, but the return side ball valve 15 is often forgotten to be closed.
In that case, as indicated by the chain double-dashed line in the figure, pump pressure is applied during operation, and back pressure is applied from the return header 11 to the branch pipes 12d and 12h that are at rest, and the cooling water flows from the opening 12dd of the branch pipe. May flow backwards and spill out, damaging the equipment.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a cooling device for an injection molding machine, which can prevent a backflow phenomenon of a branch pipe during rest due to forgetting to close a valve.

"Means for Solving the Problems" In the present invention, in order to achieve the above object, a portion that includes a supply-side header and a return-side header, and branches from these headers and requires each cooling in the injection molding machine In a cooling device of an injection molding machine in which cooling water is supplied to each system via a branch pipe connected to, only a flow of cooling water from the branch pipe to the return header is provided at a connection portion of the branch pipe to the return header. It is characterized in that a check valve for allowing the above is provided.

[Action] Since a check valve is provided on the return side of each branch pipe, even if you forget to tighten the ball valve on the return side, pump pressure will be applied and back pressure will be applied to the branch pipe when it is at rest from the return side. Backflow can be prevented by the action of the check valve. Therefore, the cooling water does not spill out of the branch pipe when it is at rest.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. The same components as those described in the conventional example are designated by the same reference numerals, and the description thereof will be omitted.

FIG. 1 shows a first embodiment of the present invention. This embodiment is an example having a total of three cooling systems including a hopper lower portion 3b of the injection device and fixed and movable molds 6 and 7. Branch pipes branched from both headers 10 and 11 at each cooling target location
12a to 12c are connected, and the check valve instead of the ball valve is connected to the return side header 11 of the return side branch pipes 12e to 12g.
20 are provided so as to extend in the vertical direction. Also,
Both headers 10 and 11 have dormant branch pipes 12d and 12h in which the pipe connections in the middle are broken, but the header 1 of these branch pipes 12d and 12h
A ball valve 13, a flow meter 14, and a check valve 20 are also attached to the connecting portions to 0 and 11 in the same manner as the branch pipes 12a to 12c and 12e to 12g. The check valve 20 has a structure that allows the flow in the forward direction, that is, the flow of the cooling water from the header 10 on the supply side to the header 11 on the return side, but blocks the reverse flow.

According to the cooling device of the injection molding machine having the above-described configuration, when there are the branch pipes 12d and 12h which are not in operation, it is only necessary to close the ball valve 13 on the supply side associated with the branch pipes 12d and 12h.

In this state, drive the pump (not shown) to bring the branch pipe 12a in use.
Even if back pressure is applied to the return side branch pipe 12h which is not operating even if pressure is applied to the return side header 11 via the ~ 12c, the check valve 2
Since 0 is provided, backflow of cooling water can be prevented.
Therefore, the problem that the cooling water leaks from the branch pipe 12h on the return side during suspension and damages the device does not occur.

FIG. 2 shows that when branch pipes 12e on the return side are connected to the header 11 on the return side, the branch pipes 12e are connected laterally (left and right in the figure) and a check valve 20 is provided there. Here is an example.

With such a configuration, it is possible to prevent backflow from the branch pipe 12e as in the case of the above embodiment, and it is possible to reduce the height of the return side header 11 and the check valve 20 associated therewith, so that both headers 10,
Even if the interval x of 11 cannot be set wide, there is an advantage that it can be easily arranged.

In the above embodiment, the ball valve 15 on the return side is eliminated and the check valve 20 is provided instead of the ball valve 15. However, the ball valve 15 is mounted as it is and a new check valve 20 is added. It may be configured.

[Advantages of the Invention] As described above, according to the present invention, since the check valve is provided at the connecting portion of each branch pipe to the return side header, back pressure is applied to the return side branch pipe during suspension. However, the backflow can be prevented by the action of the check valve, and unlike the conventional device, there is no problem of forgetting to close the valve and spilling the cooling water from the return side branch pipe which is idle.

[Brief description of drawings]

FIG. 1 is a side view of an essential part of a first embodiment of the present invention, FIG. 2 is a detailed view of an essential part of a second embodiment of the present invention, and FIG. 3 is a cooling device for a conventional injection molding machine. FIG. 2 …… Clamping device 3 …… Injection device 10 …… Supply header 11 …… Return header 13 …… Ball valve 14 …… Flowmeter 20 …… Check valve

Claims (1)

[Scope of utility model registration request] 1. A supply-side header and a return-side header are provided, and cooling water is supplied for each system via a branch pipe branched from the header and connected to a portion in the injection molding machine that requires cooling. In a cooling device of an injection molding machine, a check valve that allows only a flow of cooling water from a branch pipe to a return header is provided at a connecting portion of the branch pipe to the return header. Machine cooling system.