JPH04223117A - Automatic opening/closing device and controlling device of delivery port of hopper of molder - Google Patents

Abstract

PURPOSE:To prevent molten resin from leaving in the interior of the injection device and the like of a molder and sweating from developing in the interior of a mold. CONSTITUTION:The delivery port of a hopper is automatically blocked with a shutter plate before the stop timing of a molder by the predetermined stop preparatory timing (or time before the stop timing by the time required for completing the discharge of all the molten resin in the interior of the injection device 3 and the like). Further, piping, through which the cooling water is supplied to the cooler of a mold 4, is automatically blocked at the stop timing.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic outlet opening/closing device disposed at a hopper outlet of a molding machine, and a control device for controlling the supply of cooling water to a mold of a molding machine.

0002

[Prior Art] A hopper for supplying molding material to an injection device, an injection device for melting the supplied molding material and injecting it into a mold, and opening and closing at a predetermined timing while supporting the mold. An injection molding machine is provided, which is comprised of a mold clamping device and a mold clamping device.

Here, the hopper is equipped with a cylindrical tank, and is a device that supplies the granular resin material stored in the tank to the heating cylinder of the injection device from the outlet at the bottom end of the tank. . Note that the hopper is generally provided with a hot air dryer (hopper dryer) for drying the resin material in the tank. In addition, the injection device melts the resin material supplied from the delivery port of the hopper in the heating cylinder, advances it to the injection port (nozzle) with a screw, and injects it into the mold at high pressure from the injection port. It is a device. Further, the mold clamping device is a device that supports the mold and opens and closes the mold at a predetermined timing. The mold is equipped with a cooler to quickly solidify the resin material in the mold, and water stored in a tank or tap water is supplied to the cooler through piping. .

0004

[Problems to be Solved by the Invention] (1) There are cases where it is desired to manufacture molded products of different colors using the same molding machine. In such a case, first, after producing a desired number of molded products of the first color, the operation of the molding machine is temporarily stopped. Next, the molding material of the second color is set in the tank of the hopper, the molding machine is operated, and a molded product of the second color is manufactured. but,
During the initial stage of manufacturing the second color molded product, the first color molding material remains between the hopper delivery port and the injection device injection port. A mixture of colors occurs. The present invention prevents such color mixing, and the first
The first objective is to improve the yield of molded products of a second color and eliminate waste of molding material, and to shorten the time for changing colors at the initial stage of production.

(2) There is a demand for automatic operation of molding machines at night or on holidays. In this case, it is necessary to automatically stop the operation of the molding machine after producing a desired number of desired molded products. For this purpose, the following problems must be solved. (a) It must be prevented that the molding material remains in the heating cylinder of the injection device after automatic shutdown of the device. If it remains, it will take effort to remove the material the next time it is used, resulting in wasted time. Further, the removed molding material was once melted within the heating cylinder and was not in the form of particles. It has also changed to some extent. Therefore, even if it is set in a hopper for reuse, it cannot be fed smoothly into the heating cylinder, and there are also problems with quality. (b) Automatically stop the operation of the hopper, the heating means for the hopper, the injection device, the mold clamping device, the cooling water supply device, and the device for taking out the molded product at a predetermined timing, thereby wasting molding material. , waste of energy, and waste of cooling water must be prevented. Especially regarding cooling water,
If the supply of cooling water cannot be stopped promptly, dew condensation will occur within the mold, causing rust within the mold, so the supply of cooling water must be reliably stopped. A second purpose of the present invention is to meet such demands.

[0006]

[Means for solving the problem] The first invention is as claimed in claim 1.
As described in , (a) a shutter plate having a molding material passage hole formed approximately in the center and slidably disposed at the molding material delivery port of the hopper; and (b) a shutter. - By displacing the plate in the sliding direction, the shutter
Align the passage hole of the plate with the outlet of the hopper, or
(c) means for inputting information specifying the stop timing of the molding machine; (d) means for detecting a state corresponding to the information; (e) At a predetermined timing prior to the stop timing of the molding machine, the air cylinder is actuated based on the input information and the detected state so as to close the hopper delivery port with a shutter plate. This is an automatic opening/closing device for a hopper delivery port, which is equipped with a control means for controlling the operation of the hopper.

[0007] In the above, as stated in claim 2,
(c) the input means is configured as a means for inputting the number of molded pieces, and (d) the detection means is configured as a means for counting the number of molded pieces, and (e) the control means is configured to: Configured as a means for determining the operation timing of the air cylinder based on the number of pieces to be molded, the number of pieces molded, and the number of pieces that can be molded with the molding material existing between the delivery port of the hopper and the injection port of the injection device. You may.

[0008] Furthermore, as described in claim 3, the above (
c) the input means is configured as a means for inputting a scheduled stop time of the molding machine, and the (d) detection means is configured as a current time detection means, and the (e) control means is configured to input a scheduled stop time of the molding machine. It is configured as a means for determining the operation timing of the air cylinder based on the scheduled time, the current time, and the time required for molding with the molding material existing between the delivery port of the hopper and the injection port of the injection device. Good too.

[0009] The second invention is as described in claim 4,
(a) A cooling water supply device for cooling the mold;
(b) input means for inputting information specifying the stop timing of the molding machine; (c) detection means for detecting a state corresponding to the above information; (d) input information and detected information. This is a control device for a molding machine including a control means for stopping the supply of cooling water at the timing of stopping the molding machine based on the state of the molding machine.

[0010] In the above, as described in claim 5,
(a) the supply device is a pipe connected to a cooler;
The pipe is configured to include a valve interposed in the middle of the pipe, and a solenoid for opening and closing the valve.
(d) Control by the control means may be performed such that the valve is opened by supplying power to the solenoid, and the valve is closed by cutting off the power supply. In that case, even if the molding machine stops due to a power outage, etc.
Cooling water supply can be stopped.

[0011] Furthermore, as described in claim 6, (e)
A means for detecting the operating state of the device for taking out the molded product from the mold is provided, and the control by the control means (d) stops the supply of cooling water when an abnormality occurs in taking out the molded product. You may go as follows. In that case, the supply of cooling water can be stopped when the molding machine is stopped due to an abnormality in taking out the molded product.

0012

[Operation] In the first invention, the stop timing of the molding machine (e.g., scheduled stop time, scheduled number of pieces to be manufactured) is specified in advance by the input means, and then the molding machine is operated to start manufacturing the molded product. . Further, the detection means detects the state corresponding to the above-mentioned stop timing (for example, the current time and the number of products manufactured to date). Note that the detection of the above state by the detection means does not need to be carried out continuously during the manufacture of the molded product. As a result, when a condition indicating a predetermined timing prior to the stop timing of the molding machine (for example, a predetermined time before the scheduled stop time, or a predetermined number of pieces smaller than the planned number of pieces to be manufactured) is detected, the control means controls the air cylinder. is activated. This causes the shutter plate to slide and close the hopper delivery port.

Thereafter, the supply of molding material from the hopper is stopped, and the injection device injects the molding material remaining in the heating cylinder of the device into the mold. Thus, when stopping,
Molding material is prevented from remaining in the heating cylinder. Further, by injecting all the remaining molding material into the mold, the planned number of molded products is obtained. Furthermore, in the second invention, the supply of cooling water is stopped at the timing when all the molding material remaining in the heating cylinder is finished being injected (=timing when the molding machine is stopped). This prevents wastage of cooling water and also prevents rust from forming due to dew condensation within the mold.

[0014]

[Examples] Examples of the present invention will be described below.

(1) Overall configuration of injection molding machine FIG. 1 is a schematic diagram showing the system configuration of an injection molding machine to which the apparatus according to the embodiment is applied. As shown in the figure, this injection molding machine includes a hopper 1, an automatic outlet opening/closing device 2 disposed at the outlet of the hopper 1, and an injection device 3 for injecting the molding material supplied from the hopper 1. and mold 4
and a mold clamping device 5 that opens and closes while supporting the mold 4.
A take-out device 6 for taking out the molded product from the mold 4
, a cooling water supply device 7 for supplying cooling water to the mold 4 , a control device 8 , and an operation panel 9 equipped with various input switch groups and a display panel.

The hopper 1 is equipped with a cylindrical tank for storing the granular resin material (molding material) and a hopper dryer for stirring the granular resin material while blowing hot air. - The dryer is the drive unit 1a
Driven by. In addition, the operation of the drive device 1a is started.
The timing of the stop is controlled by the control device 8. The automatic delivery port opening/closing device 2 is a device for opening and closing the delivery port of the hopper 1 . The details will be described later. The injection device 3 is a device that melts the granular resin material supplied from the hopper 1 with a heater and injects it into the mold 4 through the nozzle at the left end in the figure.
driven by a. The timing of starting and stopping the operation of the drive device 3a is controlled by a control device 8. The mold 4 is a mold for cooling and solidifying the molten resin material injected from the injection device 3 in a cavity and molding it into a desired shape. Note that the mold 4 is provided with a cooler. The mold clamping device 5 is a device that opens and closes the mold 4 using hydraulic pressure. For example, when closing the mold 4, a hydraulic pressure P1 is applied by the hydraulic drive device 5a. Moreover, when opening, oil pressure P2 is applied. Hydraulic drive device 5
The timing of starting and stopping the operation of a is controlled by a control device 8. The retrieval device 6 is constituted by, for example, a robot having a retrieval hand. The timing of starting and stopping the operation of the take-out device 6 is controlled by the control device 8. Further, the number of molded products taken out and, if an abnormality occurs during takeout, are sent to the control device 8 as detection signals. The cooling water supply device 7 is a device for supplying cooling water to the cooler provided in the mold 4 . As illustrated in FIG. 7, the cooling water supply device 7 includes a cooling water pipe 73, a pump 72 for delivering cooling water, a valve 71 opened and closed by a solenoid, and the like. Further, the timing of starting and stopping the operation of the pump 72 and the opening and closing of the valve 71 are controlled by the control device 8. The operation panel 9 is equipped with a group of switches for inputting the timing for starting and stopping the operation of the injection molding machine. For example, the main switch for starting operation, the time input switch for inputting the scheduled stop time of the injection molding machine, the production quantity input switch for inputting the planned production quantity, or the size of the molded product (= molded product There are switches, etc. for specifying the amount of resin material consumed per piece. A display panel is also arranged to display various messages and the like to assist these input operations. The control device 8 is the drive device 1 of the hopper dryer.
a. Start of operation of the injection device drive device 3a, the hydraulic drive device 5a of the mold clamping device, the take-out device 6, and the pump 72.
This is a device that controls the stop and also controls the opening and closing of the valve 71. In addition, air cylinder drive device 2a (described later)
It is also a device that controls the operation of the These controls are controlled by command signals from the operation panel 9 and the take-out device 6.
This is done based on the detection signal from.

(2) Operation start/stop control of injection molding machine Next, the control performed by the control device 8 will be explained. Note that the control device 8 may be configured by a hard circuit using a relay or the like, or may be configured by using a CPU. First, control when using the CPU will be explained.

(2-1) Main Routine FIG. 8 is a flowchart showing the main routine of processing executed by the CPU of the control device 8. As shown in the figure, the control CPU executes the processes of steps S1 to S7 for a predetermined period of time (for example, 30 minutes) managed by the loop management process (S7).
(about m sec). Here, step S1 is a process for accepting a signal when the signal is input. For example, when a switch input is made from the operation panel 9, a process of accepting the input;
Alternatively, it is a process of accepting a detection signal from the extraction device 6. Note that processing for accepting the current time from a clock IC (not shown) is also performed. Further, step S3 is a process for managing the start and stop of operation of this device. The step S3
The processing will be described in detail later. Also, step S5
outputs control signals to the hopper dryer drive device 1a, air cylinder drive device 2a, injection device drive device 3a, hydraulic drive device 5a, molded product removal device 6, and cooling water supply device 7 shown in FIG. This is a process for The control signal is, for example, a signal that instructs to start and stop the operation, and its output is executed in response to the command in step S3.

(2-2) Operation start/stop subroutine Next, step S3 (operation start/stop processing) will be explained. As mentioned above, this operation start/stop processing subroutine is a process executed at step S3 in the main routine. So, for example, 30 mse
Executed every c.

First, it is determined whether or not the present injection molding apparatus is in operation (S11). Initially, the injection molding apparatus is stopped, so the determination is "NO" and step S
Proceed to 13. In step S13, it is determined whether the main switch on the operation panel has been turned on. If it is not turned on (S13;
NO), immediately return to the main routine. That is, "Step S11; NO→Step S13; NO→Return"
By repeating this process, the CPU enters a standby state with the main switch turned on.

In the standby state, when the main switch is turned on (S13; YES), the hopper-dryer drive device 1a, the injection device drive device 3a, and the hydraulic drive device 5
a. Start the operation of the molded product removal device 6 and the cooling water supply device 7 (S15). Further, the drive device 2a is controlled so that the air cylinder 21 is in the state shown in FIG. Note that the control signal for starting the operation of each device is outputted to each device in step S5, as described above.

In step S17, it is determined whether it is time to prepare for stopping. What is the stop preparation timing?
Before stopping the operation of this injection molding machine, it is time to close the hopper delivery port. For example, if the scheduled stop time of the injection molding machine is input, the time before the specified time (=the time required to finish injecting all the molten resin in the injection device 3) is ,
This corresponds to the above stop timing. In addition, if the planned number of molded products to be manufactured and the size of the molded product (=material consumption per molded product) are input, a predetermined number of molded products (=injection device 3 This is the timing when only a small number of molded products can be manufactured using the molten resin present in the molded product. In addition, step S
The determination in step 17 is "NO" during normal operation. That is, "Step S11; YES → Step S17; N
By repeating the process "O→Step S21; NO→Step S31; NO→Return", the CPU enters a standby state for the stop preparation timing, and during this period, normal operation is performed. Note that the determination in step S17 is "NO" even while waiting for the following stop timing.

Next, during normal operation, step S
17 is ``YES'', air cylinder 2
1 to close the delivery port of hopper 1 (S
19). That is, the drive device 2a is controlled so that the air cylinder 21 is in the state shown in FIG. Note that the control signal to the drive device 2a is outputted in step S5, as described above.

In step S21, it is determined whether or not it is time to stop. For example, if the scheduled stop time of the injection molding machine has been input, it is determined whether the scheduled stop time has arrived. Further, if the planned number of molded products to be manufactured has been input, it is determined whether the planned number of products has been manufactured. After the stop preparation timing, the determination in step S21 is "NO" until the stop timing comes. That is, "Step S11; YES → Step S
17; NO→Step S21; NO→Step S31;
By repeating the process "NO→Return", the CPU enters a standby state for the stop timing, and during this time, molding is performed by injecting the resin material remaining in the injection device 3. Note that the determination in step S21 is "NO" even while waiting for the stop preparation timing.

In this way, all the resin material remaining in the injection device 3 is consumed, and the determination in step S21 is "
YES”, the hopper dryer drive device 1a,
The operation of the drive device 3a of the injection device, the hydraulic drive device 5a, the molded product removal device 6, and the cooling water supply device 7 is stopped (S23). In addition, the cooling water supply device 7
Stopping the operation also means closing the valve 71. Further, the control signal for stopping the operation of each device is outputted to each device in step S5, as described above.

Control by the control device 8 is performed in the manner described above. In addition, in FIG. 9, step S31 is while waiting for the stop preparation timing or while waiting for the stop timing (S11; YES → S17; NO → S21; NO →
During S31; NO→return processing), an abnormality in taking out the molded product from the taking out device 6 (
(S31; YES), the hopper dryer drive device 1a
, the operation of the cooling water supply device 7, etc. is stopped (S23).
This is a process for

(3) Automatic opening/closing device for hopper delivery port Next, the mechanism of the automatic opening/closing device 2 for the hopper delivery port will be explained with reference to FIGS. 2 to 6. In this example, a case is explained in which the automatic opening/closing device 2 for the hopper delivery port is installed at the delivery port of the hopper of an injection molding machine, but instead of this, an extrusion molding machine, a blow molding machine, etc. It is also possible to use it by disposing it at the outlet of a hopper of a machine, a calender molding machine, etc.

As shown in the figure, the automatic opening/closing device 2 includes a shutter plate 22 having a molding material passage hole 22b formed approximately in the center, and an air supply for displacing the shutter plate 22 in the left-right direction in the figure. The cylinder 21 is disposed at the outlet of the hopper 1 by supporting members 23, 24, 24a, 26a, 26b, and 25.

That is, two upper and lower support plates 23 are fixedly interposed perpendicularly to the pipe 11 in the middle of the delivery pipe 11 at the lower end of the hopper 1.
A shutter plate 21 is slidably disposed between the support plates 23-23. In addition, two support plates 23, 23
Like the shutter plate 22, a passage hole 23b for the molding material is formed in the , and the operating state of the device (= the state in which the molding material is supplied from the hopper 1 to the injection device 3).
At this time, the passage hole 23b is communicated with the passage hole 22b of the shutter plate 22 (see FIG. 6). In addition, the above 2
Gap between the supporting plates 23, 23 (=shutter plate 2
2) is the gap that allows the 2 to slide in the left-right direction in the figure.
Fasteners 24 at each of the four corners of the support plates 23, 23, and
It is secured by fixing means such as bolts 24a.

On the other hand, from each stopper 24 on the right side of the figure,
Frames 26a and 26b extend horizontally to the right in the figure, and a cylinder bracket 25 that supports the distal end of the air cylinder 21 is fixed to the right end of the frames 26a and 26b. has been done. Note that the tip of the rod 21a of the air cylinder 21 is connected to the shutter.
It is connected to a side wall 22a on the right end side of the plate 22.

In this way, the air cylinder 21 slides the shutter plate 22 in the left-right direction in the figure to close the hopper delivery port (in the case of FIG. 5) or to communicate it (in the case of FIG. 6). is realized. The timing for operating the air cylinder 21 is as described in (2) above.
) Since it was explained in detail in the section explaining the control, the explanation here will be omitted.

(4) Control by relay circuit Next, FIG.
A case will be explained in which the relay circuit controls the operation of the air cylinder 21 of the automatic opening/closing device 2 of the hopper delivery port and the opening/closing of the valve 71 interposed in the middle of the piping 73 of the cooling water supply device 7. do. In addition, valve 7
1 is a valve that opens while power is being supplied to the solenoid S2 and closes when the power supply is cut off.

In FIG. 10, SW1 is a switch that is closed at the stop preparation timing in response to a signal from the control device of the molding machine, and SW2 is a switch that is closed in response to a signal from the control device of the molding machine. The switch is closed at the stop timing. Also, SW3 is the take-out device 6
This is a switch that is closed in response to a signal from the control device of the molding machine when a signal indicating the occurrence of an abnormality (such as a falling molded product) is input from the molding machine. Further, S1 is a solenoid for operating the air cylinder 21, and when power is supplied to the solenoid S1, the air cylinder 21 operates as follows.
The state shown in FIG. 5 (the hopper-feeding port is blocked) is reached. Further, S2 is a solenoid for operating the valve 71. While power is being supplied to the solenoid S2, the valve 71 is open and cooling water is supplied to the mold 4.
is supplied to the cooler. Further, R1 is a relay coil, and r1 is a normally open contact operated by the relay coil R1. Moreover, R2 is a relay coil, and r2
is a normally closed contact operated by the relay coil R2.

In the relay circuit configured as described above, when the switch SW1 is closed by a signal from the control device of the molding machine at the stop preparation timing, the relay R1 is activated and the relay contact r1 is closed. Ru. This allows solenoid S
1, the ERI cylinder 21 is activated and enters the state shown in FIG. 5 (hopper-discharge port cutoff state). Further, when the switch SW2 is closed by a signal from the control device of the molding machine at the above-mentioned stop timing, the relay R2 is closed.
is activated, relay contact r2 opens, power supply to solenoid S2 is cut off, and valve 71 is closed. This results in
Cooling water supply is stopped. Further, when a signal indicating the occurrence of an abnormality (dropping of a molded product, etc.) is input from the take-out device 6 and the switch SW3 is closed, the relay R2 is activated and the relay contact r2 is activated in the same way as described above. is opened and the supply of cooling water is stopped.

[0035]

Effects of the Invention As described above, the first invention enables the material to be fed out of the hopper at a predetermined stop preparation timing prior to the stop timing of a molding machine such as an injection molding machine, an extrusion molding machine, a blow molding machine, a calender molding machine, etc. It is an automatic opening/closing device that closes the mouth. Moreover, the second invention is a control device that stops the supply of cooling water to the mold cooler of the molding machine at the timing when the molding machine is stopped.

According to the first invention, when the molding machine is automatically stopped, molten resin material is prevented from remaining between the outlet of the hopper and the nozzle of the injection device. Therefore, the next time the molding machine is used, it can be operated immediately. Furthermore, even if the device is activated immediately, the color of the previous molded product will not be mixed into the new molded product.

Furthermore, according to the second aspect of the present invention, when the molding machine is stopped (scheduled stoppage, stoppage due to power outage, etc., stoppage due to an abnormality in taking out the molded product, etc.), cooling water is reliably supplied. It can be stopped. Therefore, it is possible to prevent wastage of cooling water and also to prevent rust due to dew condensation inside the mold.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the system configuration of a molding machine to which an embodiment device is applied.

FIG. 2 is a perspective view showing an overview of the automatic delivery port opening/closing device according to the embodiment.

FIG. 3 is a schematic diagram illustrating the mechanism of the automatic opening/closing device.

FIG. 4 is a top view of the shutter plate of the automatic opening/closing device.

FIG. 5 is an explanatory diagram showing a state in which the delivery port of the hopper is closed by the automatic opening/closing device.

FIG. 6 is an explanatory diagram showing a state in which the delivery port of the hopper is communicated with the automatic opening/closing device.

FIG. 7 is a schematic diagram showing a system configuration of a cooling water supply device controlled by the embodiment device.

FIG. 8 is a flowchart showing a main routine of processing in a control device of a molding machine to which the embodiment apparatus is applied.

FIG. 9 is a flowchart showing operation start/stop processing in a control device of a molding machine to which the embodiment device is applied.

FIG. 10 is a circuit configuration diagram for controlling the operation of the embodiment device.

[Explanation of symbols]

1 Hopper 2 Automatic opening/closing device for delivery port 21 Air cylinder 22 Shutter plate 23 Support plate 3 Injection device 4 Mold 5 Mold clamping device r1 Normally open relay contact r2 Normally closed relay contact

Claims (6)

[Claims] 1. An automatic opening/closing device for a hopper/outlet of a molding machine, comprising the following structural requirements (a) to (e). (a) A shutter plate provided with a passage hole for the molding material in the approximate center and slidably disposed at the delivery port of the hopper; (b)
) An air cylinder that aligns the passage hole of the shutter plate with the outlet of the hopper by displacing the shutter plate in the sliding direction, or closes the outlet of the hopper with the shutter plate, (c) Input means for inputting information specifying the stop timing of the molding machine; (d) Detection means for detecting a state corresponding to the above information; (e) Shutter control at a predetermined timing prior to the stop timing of the molding machine. - A control means for operating an air cylinder based on input information and a detected state so as to block the outlet of the hopper with a plate. 2. In claim 1, the input means (c) is means for inputting the number of pieces to be molded;
The (d) detection means is a means for counting the number of molded pieces, and the (e) control means is a means for counting the number of pieces to be molded, the number of molded pieces, and the number of pieces to be molded, and the number of pieces to be molded, and the number of pieces to be molded, and the number of pieces that have been molded, and the number of pieces that have been molded, and the number of pieces that have been molded. An automatic opening/closing device for the hopper and delivery port of a molding machine that determines the timing of air cylinder operation based on the number of moldable pieces that can be molded using the molding material that exists during that time. 3. In claim 1, the (c) input means is a means for inputting a scheduled stop time at which the operation of the molding machine should be stopped, and the (d) detection means is a means for inputting a scheduled stop time at which the operation of the molding machine should be stopped; (e) The control means detects the scheduled stop time, the current time, and the time required for molding with the molding material that exists between the delivery port of the hopper and the injection port of the injection device. An automatic opening/closing device for the hopper delivery port of a molding machine that determines the operation timing of the air cylinder based on the 4. A control device for a molding machine, comprising the following structural requirements (a) to (d). (a) Cooling water supply device for cooling the mold, (b
) an input means for inputting information specifying the stop timing of the molding machine; (c) a detection means for detecting a condition corresponding to the above information; (d) based on the input information and the detected condition. , a control means for stopping the supply of cooling water at the timing of stopping the molding machine. 5. In claim 4, the supply device (a) comprises a pipe connected to a cooler, a valve interposed in the middle of the pipe, and a solenoid for opening and closing the valve. (d) The control means opens the valve by supplying power to the solenoid, and closes the valve by cutting off power supply. A control device for a molding machine. 6. The method according to claim 4, further comprising: (e) means for detecting an operating state of a device for taking out a molded article from a mold; A control device for the molding machine that stops the supply of cooling water when a problem occurs.