JPH03174967A - Method and apparatus for removing casting flash in gas vent device in injection forming machine - Google Patents

Abstract

PURPOSE:To avoid deposit of casting flash into a movable valve and to prevent flowing-in of molten material into an opening/shutting valve by repeatedly opening/ shutting the opening/shutting valve to detach the casting flash with mechanical impacting force and supplying cleaning fluid to remove and discharge the detached casting flash. CONSTITUTION:A control part 10 generates ON-OFF driving signal in charging-over means based on signal from casting machine control part 26, and by executing ON-OFF driving in solenoid valves 14, 15, the opening/shutting operation in the opening/shutting valve 8 is repeatedly executed. By this method, the movable valve 8a detaches and removes the casting flash from the movable valve 8a, valve seat 8d, etc., with mechanical impacting force colliding to the valve seat 8d. Further, by the signal from the casting machine control part 26, the control part 10 generates fluid driving signal for cleaning and ON-OFF starting signal in a solenoid valve 25 for supplying cleaning fluid, is outputted to the solenoid valve 25 from the control part 10. Then, the casting flash is detached and removed and at the sane time, the solenoid valve 25 is turned to ON and the cleaning fluid is supplied into the opening/shutting valve 8 from a fluid source 24.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a cast waste removal method and a cast waste removal device for a gas venting device in an injection molding machine such as a die casting machine.

[Conventional technology]

In injection molding methods such as die casting, gas in the cavity during injection causes cavities in the cast product, so it is necessary to remove the gas.

Conventionally, in a gas venting device for injection of an injection molding machine, a valve is provided in a gas venting hole led from a mold cavity, and hot water is filled into the cavity with the valve open to release gas. A method is known in which gas is discharged to the outside of the mold through the gas vent hole.

However, the above degassing device is configured to exhaust gas while the valve closes at the speed of the filled molten metal, so it is necessary to have a sufficient melt speed for the valve to close, so it is not used for low-speed casting. The structure is such that the hot water bypasses the bypass before closing the valve, but if this timing varies, the hot water may scatter out of the mold from the gas vent hole, or gas venting may be incomplete. There was a problem.

Therefore, in order to solve the problems of the conventional gas venting device, as disclosed in, for example, Japanese Utility Model Application No. 61-195853 and Japanese Patent Application Laid-open No. 83-80059, gas is introduced from the cavity of the dividing surface of the mold. A degassing on/off valve is provided at the opening of the provided degassing passage, and a detection rod for the molten material to be injected is placed in the middle of the opening, and when the on/off valve is open, the detection rod degass A valve drive mechanism electrically connected to the detection rod is activated to open and close the valve through an electric circuit as a control section configured to detect the molten material to be injected that has flowed into the passage, and to operate based on the detection signal. A gas venting device has already been developed that closes a valve and discharges the gas inside the cavity to the outside of the mold while the on-off valve is closed.

[Problem to be solved by the invention]

In the gas venting device of the above type, the detection rod detects the molten material to be injected in the middle of the gas venting path, and the valve drive mechanism closes the opening/closing valve. This method can solve the problem of scattering of the molten material to be injected, and high-speed casting can also be applied to low-speed casting.

However, when using the above-mentioned gas venting device, if the gas is vented to the atmosphere instead of using vacuum suction or an air vent to exhaust the gas from the cavity, other solids may enter the on-off valve due to the gas flow. Due to manufacturing accuracy and assembly accuracy of the parts of the on-off valve, deformation due to collision between the on-off valve and the valve seat during the closing operation of the on-off valve, etc., when the valve closes,
It is extremely difficult to prevent a gap from forming between the on-off valve and the valve seat, and since a gap inevitably occurs, there will be leftover casting in that gap. If left for a long time, it will gradually accumulate and eventually cause problems such as malfunction of the on-off valve or intrusion of the molten material to be injected into the on-off valve, making it impossible to vent gas.

The present invention aims to solve the problems of the above-mentioned gas venting device, and after taking out the molded product, the solenoid valve for opening and closing the opening and closing valve is turned on using a signal from the casting machine control section as a start signal.
At the same time, the solenoid valve for supplying cleaning fluid is turned ON and OFF, and the on-off valve is repeatedly opened and closed, and the mechanical impact and the supply of cleaning fluid at this time cause the valve seat and It is an object of the present invention to provide a method and device for removing cast waste from a gas venting device in an injection molding machine, which allows cast waste and other solids inside a valve to be discharged to the outside.

[Means to solve problems]

In order to achieve the above object, according to the present invention, a gas venting opening/closing valve is provided at the opening of the gas venting path led from the cavity of the split surface of the mold, and the molten material to be injected is placed in the middle of the gas venting path. A detection rod is provided, and when the opening/closing valve is open, the detection rod detects the molten material to be injected that has flowed into the gas venting passage, and the detection is performed via a control section configured with a circuit configured to be activated by the detection signal. An injection molding machine that discharges gas in a cavity to the outside of a mold while a valve driving mechanism consisting of a valve switching means and a valve operating means electrically connected to a rod is operated to close the on-off valve. In the degassing device, (a) after taking out the molded product from the mold, a start signal is generated from the casting control section, and (b) the start signal is transmitted to the control section to control the ON/OFF drive signal of the valve switching means. and (c) generate a cleaning fluid supply means driving signal, and (c) turn the switching means ON and OFF.
The valve switching means is repeatedly activated within a short time by the drive signal.
By operating N, OFF, the on-off valve is repeatedly opened and closed, and the as-cast material is peeled off by the mechanical impact force, and (d
) At the same time as this peeling operation, a cleaning fluid is supplied into the opening/closing valve and the cavity from a cleaning fluid supplying means drive signal to remove the peeled cast waste and discharge it out of the mold. A method for removing cast-off gas from a gas venting device in a molding machine is provided.

Furthermore, in the present invention, a gas venting opening/closing valve is provided at the opening of the gas venting path 5 led from the cavity of the dividing surface of the mold, and a detection rod for the molten material to be injected is arranged in the middle of the gas venting path.
The detection rod detects the molten material to be injected that has flowed into the gas vent passage when the on-off valve is open, and is electrically connected to the detection rod through a control section configured to operate in accordance with the detection signal. A gas venting device for an injection molding machine that discharges gas in a cavity to the outside of a mold while a valve driving mechanism comprising a valve switching means and a valve operating means operates to close the opening/closing valve. It has a cleaning fluid supply means connected to the opening, and a casting control unit that generates a casting removal start signal after removing the molded product from the mold, and the control unit includes:
In an injection molding machine, the injection molding machine is connected to the casting control unit and the cleaning fluid supply means, and generates a valve switching means 0NOFF drive signal and a cleaning fluid supply means drive signal in response to the casting removal start signal. We provide cast-off removal equipment for degassing equipment.

[For production]

When the cavity is filled with the molten material to be injected with the on-off valve open, the molten material flows into the gas vent passage and when it comes into contact with the detection rod, the molten material to be injected is electrically conductive, so the control section is activated. It operates and outputs a voltage several times the rated voltage to the valve switching means for a short period of time.

When a solenoid valve is used as the valve switching means, this actuates the solenoid valve and compressed air from the compressor of the valve actuating means is supplied to the piston front chamber of the valve actuating cylinder.

At the same time, the compressed air in the rear chamber of the piston of the valve actuating cylinder is released to the atmosphere, so that the on-off valve is closed.

Further, when an electromagnet is used as the valve switching means, the electromagnet is excited by the output of the control section, and the on-off valve is closed by attracting the magnetic body provided with the movable valve.

When molding is completed, the mold is opened and the molded product is taken out.

After the molded product is taken out and while the mold is being closed, the casting machine sprays release agent and air onto the mold, so there are no signals from the casting machine control unit such as a release agent spray start signal, an air blow start signal, etc. The signal is output to the control section as a casting removal start signal, and the valve switching means is turned on and off.
Since the drive signal and the cleaning fluid supply means drive signal are generated, the valve switching means repeats ON and OFF several times, and the solenoid valve for cleaning fluid supply is switched on at the appropriate time as shown in FIGS. 2(a) and (b). It is repeatedly turned ON and OFF, or it is turned ON continuously.

As a result, the on-off valve is repeatedly opened and closed, and the cast-off adhering to the on-off valve, the valve seat, etc. is removed by a mechanical impact force due to the collision between the on-off valve and the valve seat.

At the same time, the cleaning fluid supply means is activated and the cleaning fluid is supplied from the fluid source into the gas vent passage, that is, into the on-off valve, so that the solids that have entered the on-off valve are removed from the mold. is discharged and removed.

After the above operations, the normal molding cycle is repeated.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

First, the degassing device is constructed as follows.

As shown in FIG. 1, a degassing passage 5 communicating with a cavity 4 is provided in the dividing surface 3 of both the fixed mold 1 and the movable mold 2. As shown in FIG.

The gas vent passage 5 is provided on the opposite side of the gate 6 to the cavity 4, and its outer end is open to the atmosphere or connected to a vacuum suction device 7 as shown in the figure, so that the cavity 4 is closed during injection. The gas inside can be sucked and discharged outside the mold.

The vacuum suction device 7 includes a 1i magnetic valve 7a, a tank 7b, a vacuum pump 7c, and a motor 7d.

Further, the degassing passage 5 is provided with an on-off valve 8 at its outer end 5a for freely opening and closing the degassing passage 5, and a conductive melt to be injected ( A detection rod 9 made of a conductive material is provided in each case to detect the molten metal.

The detection rod 9 and the valve drive mechanism 11 are electrically connected through a control section 10 configured to be activated by contact of the detection rod 9 with the molten material to be injected.

The valve driving mechanism 11 includes a valve switching means 11a and a valve operating means, and the valve operating means includes a valve operating cylinder 12, a piston 13 provided with a movable valve 8a, and a compressor 17. The valve switching means 11a is a solenoid valve 14.1
5 and an air operated valve 16.

Further, the on-off valve 8 has a valve hole 8c having a tapered valve seat 8d provided near the outer end 5a of the gas vent passage 5, and a piston rod 13a and a tapered surface attached to the tip thereof. A movable valve 8a with a movable valve 8b is fitted into the piston 13 so as to be able to reciprocate in the axial direction, and is inserted into the piston front chamber 12a of the valve operating cylinder 12 of the valve operating means via the air operated valve 16 of the valve support means 11a. At the same time, compressed air is supplied from the piston rear chamber 12b to the atmosphere, and the piston 13 is moved backward (moved to the right in FIG. 1), and the movable valve 8 is
The tapered surface 8b of a is seated on the valve seat 8d to close the valve, and compressed air is supplied to the piston rear chamber 12b via the air-operated valve 16 so as to close the gas vent passage 5 and vice versa. At the same time, compressed air is released into the atmosphere from the piston front chamber 12a, so that the piston 13 moves forward, and the movable valve 8a is separated from the valve seat 8d and opened to open the gas vent passage 5. is formed.

In addition, the gas venting path 5 may be shaped, for example, in a net shape, so that the molten material to be injected flows through the gas venting path 5 with a time delay until the molten material to be injected contacts the detection rod 9 and the on-off valve 8 is closed. It is formed into a meandering shape or the like.

Further, a casting sleeve 19 communicating with the runner 18 and having a pouring port 19a is fixed to the fixed mold 1, and a plunger 21 is advanced by the injection cylinder 20. The molten material to be injected is injected into the casting sleeve 19 from the pouring port 19a and is filled into the cavity 4 through the runner 18 and the gate 6. In this embodiment, after the plunger 21 closes the pouring port 19a, the striker 22 operates the vacuum start limit switch 23, and the casting machine control section 26 operates the electromagnetic valve 7a of the vacuum suction device 7, and the casting starts. The gas in the sleeve 19 and the cavity 4 is discharged to the outside of the mold through a gas vent path 5. However, if the vacuum suction device 7 is not provided, the gas in the cavity 4 is naturally exhausted into the atmosphere from the outer end 5a of the gas vent passage 5.

Next, a cast waste removal device and a cast waste removal method of the above-mentioned gas venting device will be explained.

In the present invention, after taking out the molded product, the valve switching means 11a of the valve drive mechanism 11 in the above-mentioned degassing device is alternately turned ON and OFF several times, thereby repeatedly opening and closing the on-off valve 8. Further, during this repeated opening/closing operation, cleaning fluid is intermittently or continuously sprayed into the opening/closing valve S.

More specifically, as shown in FIG. 1, a cleaning device such as an air blower is installed in the gas venting path 5 so that cleaning fluid can be supplied under pressure from the outer end 5a of the gas venting path 5 to the on-off valve 8. A fluid source 24 is provided via a solenoid valve 25.

Further, the pair of electromagnetic valves 14 and 15 are arranged so that the opening and closing operation of the movable valve 8a in the opening and closing valve 8 is repeated several times at constant time intervals (approximately 40 m5eC to 50m5eC).

That is, the solenoid valves 14 and 15 are alternately turned ON and OFF in a 3×3 manner as illustrated in FIG. 2 by the operation of the control unit 10.
= It is set to repeat 9 times, and as a result of repeatedly opening and closing the movable valve 8a,
Mechanical impact force due to collision when the movable valve 8a sits on the valve seat 8d nine times The movable valve 8a and the valve seat 8d in the on-off valve 8
It is designed to peel off and remove the cast waste (not shown) adhering to the movable valve 8a, valve seat 8d, etc. As the control section 10, a sequence circuit, a logic circuit, etc. can be used.

The control section 10 is connected to a casting control section 26, and the control section 10 is also connected to a solenoid valve 14, 15 for opening and closing the on-off valve 8 and a solenoid valve 25 for cleaning fluid. That is, signals from the casting machine control section 26, such as a release agent spray start signal, an air blow start signal, etc., are transmitted to the control section 1.
Based on this signal, the control section 10 generates a valve switching means 0NOFF drive signal. That is, the solenoid valves 14 and 15 are turned ON and OFF to repeatedly open and close the on-off valve 8. Furthermore, this casting control section 26
The control unit 10 generates a cleaning fluid driving signal based on a signal from the cleaning fluid. That is, the cleaning fluid supply solenoid valve 25
An ON/OFF start signal is output from the control section 10 to the solenoid valve 25. At the same time as the above-described peeling of the as-cast is removed, the electromagnetic valve 25 is turned ON, and cleaning fluid is supplied (sprayed) into the on-off valve 8 from the fluid source 24.

In addition, the casting machine control unit 26 is configured to turn on and off the solenoid valves 14 and 15.
An FF signal generation circuit and an ON/OFF signal generation circuit for the solenoid valve 25 may be incorporated, and an electronic circuit such as an IC circuit may be used as the control section 10.

The control unit 10 operates to apply a voltage (20 to 25 V) several times the rated voltage (4.5 to 5.5 V) for a short time (30 to 50 m5).
ec) is output to the solenoid valve 14, the solenoid valve 14 is activated, and compressed air is supplied to the pilot 16a of the air-operated valve 1G via the boat (a) of the solenoid valve 14, and the air-operated valve 16
is activated, compressed air is supplied to the piston front chamber 12a of the valve operating cylinder 12 through the boat (b), and at the same time compressed air in the piston rear chamber 12b is released into the atmosphere through the boat (c), and the opening/closing valve is 8 is closed.

Note that the closing operation of the on-off valve 8 to prevent molten metal from passing through the on-off valve 8 is also performed by this series of operations, but the signal to start closing the valve is a detection signal from the detection ring 9 that is sent to the control unit 1.
0, and the solenoid valves 14, 15 are actuated based on the signal.

Regarding the valve opening operation, the control unit 10 operates to output the rated voltage to the solenoid valve 15 for a short time, and the solenoid valve 15
is activated, compressed air is supplied to the pilot 16b of the air-operated valve via the boat (d) of the solenoid valve 15, the air-operated valve 16 is operated, and the compressed air passes through the boat (e) to operate the valve. The compressed air is supplied to the piston rear chamber 12b of the cylinder 12, and at the same time, the compressed air in the piston front chamber 12a is discharged into the atmosphere through the boat.

Further, the above-mentioned solenoid valves 14 and 15 are alternately turned ON and OFF as shown in FIG.
By intermittently repeating ec and OFF several times, cleaning fluid is sprayed into the on-off valve 8, thereby removing the separated cast solids, as shown in Fig. 2(b).
It is also possible to perform the ON operation continuously as shown in FIG.

After taking out the molded product, a release agent spray start signal or an air blow start signal is issued from the casting control section 26, and the signal is sent to the control section 10. Based on this signal, the solenoid valve 14.1 of the valve switching means
5 repeats the ON and OFF operation alternately, and as a result,
The movable valve 8a of the on-off valve 8 repeats opening and closing operations several times in a short period of time.

As a result, the cast parts adhering to the movable valve 8a and the valve seat 8d are peeled off from these by mechanical impact.

Simultaneously with this as-cast peeling removal operation, a drive signal is sent from the control unit 10 to the cleaning fluid supply solenoid valve 25 based on the start signal, and this solenoid valve 25 is also turned on and off.
The F operation is repeated (FIG. 2(a)) or the ON state is maintained (FIG. 2(b)), and as a result, cleaning fluid is intermittently or continuously supplied into the on-off valve 8. Therefore, other solid materials separated from the movable valve 8a, valve seat 8d, etc., are removed and discharged from the mold by this fluid.

FIG. 3 shows a second embodiment of the casting removal device of the present invention.

More specifically, in FIG. 3, the valve drive mechanism 11 is composed of a valve switching means 11a, a valve operating cylinder 12, a piston 13 with a movable valve 8a, and a compressor 17, and the valve switching means 11a is composed of one solenoid valve 30. This is an example consisting of

The solenoid valve 30 is switched at regular time intervals by the output from the control section 10.

By this switching, the movable valve 8a is repeatedly opened and closed (3×3=9 times) in the same manner as in FIG.
Peel off and remove cast iron adhering to d, etc.

On the other hand, cleaning fluid is intermittently supplied from the fluid source 24 into the on-off valve [
It is sprayed 3 times (1.5 sec/1 casting cycle) or continuously to remove peeled solids.

FIG. 4 shows a third embodiment of the casting removal device of the present invention.

In this embodiment, the valve drive mechanism 11 includes a valve switching means 11a.
A magnetic body 27 equipped with an electromagnet 28 and a movable valve 8a.
and a spring 29 that biases the movable valve 8a in the valve opening direction.

The electromagnet 28 repeats excitation and demagnetization 3×3=9 times at regular time intervals based on the output from the control section 10. As a result, the magnetic body 27 is attracted to or separated from the electromagnet 28, and the movable valve 8a opens and closes. As in the first and second embodiments, this causes the cast off particles adhering to the movable valve 8a, valve seat 8d, etc. to peel off and be removed.

Furthermore, a cleaning fluid is intermittently or continuously sprayed from the fluid source 24 to remove the peeled cast solids. The second and third embodiments have simplified structures compared to the first embodiment, so the number of parts can be reduced, and they can operate accurately and reliably.

〔Effect of the invention〕

Since the present invention is configured as described above, when the gas is discharged from the cavity 4, the cast iron or other solid matter that enters the on-off valve 8 due to the gas flow, or the movable valve 8a, the valve seat, etc. By repeatedly opening and closing the on-off valve 8 several times, the cast waste generated in the on-off valve 8 d etc. is peeled off by a mechanical impact (due to the collision between the movable valve 8 a and the valve seat 8 d), and at the same time, the cleaning material is supplied into the on-off valve 8. Foreign matter can be discharged and removed from the mold by using the casting fluid, so by removing the above-mentioned cast material and cleaning the inside of the on-off valve 8 for each shot, the opening and closing operation of the on-off valve 8 is smoothed. Moreover, since the seating of the movable valve 8a can be stabilized, it is possible to avoid the accumulation of cast waste on the movable valve 8a1 and the valve seat 8d, thereby preventing the inflow of the molten material to be injected into the on-off valve 8. As a result, the intended purpose of the degassing device is distantly forgotten.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional side view showing a first embodiment of a cast-off removal device of a gas venting device in an injection molding machine according to the present invention;
The figure is an explanatory view showing the ON/OFF operation of the solenoid valve in the same device, and FIG. 3 is a longitudinal sectional side view showing a second embodiment of the cast-off removal device of the degassing device in the injection molding machine according to the present invention. , shows an embodiment in which one solenoid valve is used as the valve switching means, and FIG. 4 is a partially longitudinal side view showing a third embodiment of the casting removing device of the gas venting device in the injection molding machine according to the present invention. This is a diagram showing an example in which a 1it magnet is used as the valve switching means. 3... Divided surface part of the mold, 4... Cavity, 5
...Gas vent passage, 8...Gas vent opening/closing valve, 9...Detection rod, 10...Control unit, 1.
...Valve drive mechanism, lla...Valve switching means, 2
...Valve actuated cylinder, 4.15... Solenoid valve, 16... Air actuated valve, 5
... Solenoid valve for supplying cleaning fluid, 6 ... Casting machine control section

Claims (2)

[Claims] (1) A gas venting on-off valve 8 is provided at the opening of the gas venting path 5 led from the cavity 4 of the split surface portion 3 of the mold, and a detection rod 9 for the molten material to be injected is provided in the middle of the gas venting path. When the opening/closing valve is open, the detection rod detects the molten material to be injected that has flowed into the gas vent passage, and is electrically connected to the detection rod via a control unit 10 configured to operate in accordance with the detection signal. A gas in an injection molding machine that discharges gas in a cavity to the outside of a mold while a valve drive mechanism 11 consisting of a valve switching means 11a and a valve operating means connected to the valve is operated to close the opening/closing valve. In the punching device, after removing the molded product from the mold, the casting control section 26 generates a casting removal start signal, and transmits the casting removal start signal to the control section 10 to turn the valve switching means ON/OFF drive signal. and a cleaning fluid supply means drive signal is generated, and the valve switching means is repeatedly turned ON and OFF within a short period of time by the switching means ON and OFF drive signals, thereby repeatedly opening and closing the on-off valve and its mechanical The as-cast part is peeled off by the impact force, and at the same time as this peeling operation, a cleaning fluid is supplied into the on-off valve and the cavity from the cleaning fluid supply means drive signal to remove the peeled off part from the mold. A method for removing cast-off gas from a gas venting device in an injection molding machine. (2) A gas venting on-off valve 8 is provided at the opening of the gas venting path 5 led from the cavity 4 of the split surface portion 3 of the mold, and a detection rod 9 for the molten material to be injected is provided in the middle of the gas venting path. When the opening/closing valve is open, the detection rod detects the molten material to be injected that has flowed into the gas vent passage, and is electrically connected to the detection rod via a control unit 10 configured to operate in accordance with the detection signal. A gas in an injection molding machine that discharges gas in a cavity to the outside of a mold while a valve drive mechanism 11 consisting of a valve switching means 11a and a valve operating means connected to the valve is operated to close the opening/closing valve. The venting device includes cleaning fluid supply means 24, 25 connected to the opening of the gas venting passage, and a casting control unit 26 that generates a casting removal start signal after removing the molded product from the mold, The section 10 is connected to the casting control section 26 and also to the cleaning fluid supply means, and outputs a valve switching means ON/OFF drive signal and a cleaning fluid supply means drive signal in response to the casting removal start signal. A cast-off removal device for a degassing device in an injection molding machine, characterized in that degassing occurs.