JPS6026624B2 - Gas venting device for mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas venting device for a mold of an injection molding machine, such as a die gas machine or an injection molding machine, which extracts a large amount of gas from a mold cavity during injection molding.

As a related matter, when molten metal is injected into the cavity of a mold at high speed and high pressure using a die gas machine, etc., the gas in the cavity cannot be sufficiently removed and remains in the product, resulting in the formation of cavities in the product. .

Therefore, a conventional method has been to place an openable/closeable valve that can close the gas exhaust path in the gas exhaust path of the mold, and to close this valve by activating a solenoid when the gas during injection has completely escaped. was considered.

However, in that case, if the valve arm of the valve is directly actuated by the action of the solenoid to close the valve, the valve will close, but the valve will become loose, so there is a possibility that the valve that was once vertical may open again. There were cases in which the molten metal progressed to the valve shank, and then the valve could no longer be opened or closed. In addition, if the valve is directly tightened by the action of a solenoid, it is usually
It is necessary to move more than the rib, making the closing operation unstable and increasing the time required for the closing operation.

The reason is that the excitation strength of the solenoid is inversely proportional to the opening position of the valve, and when the opening position of the valve is below 1 side, the suction force of the solenoid becomes extremely strong, but when the opening position of the valve is 5
This is because the suction force of the solenoid becomes extremely weak when the solenoid is close to the skin or closer to the skin. In the first place, in die gas, during low-speed injection and subsequent high-speed injection, the gas vent valve is opened to exhaust the gas inside the mold cavity, and the gas passes through the cavity and enters the gas exhaust path. It is necessary to close the valve as quickly as possible, just before the molten metal reaches the valve, but in order to ensure sufficient degassing, it is necessary to close the valve using a limit switch, etc. during high-speed injection after the gas in the cavity has been exhausted. It is necessary to give a command and activate the solenoid.

However, high-speed injection is usually performed at a speed of 2 to 4 m/sec in a short time of 0.05 to 0.1 seconds, and
Even if the cross-sectional area of the gas discharge passage is increased, at most it will only be about one-tenth of the cross-sectional area of the injection sleeve, so the speed of the port water traveling through the gas discharge passage is extremely large, exceeding the high-speed injection speed of one note. Become. Therefore, in order to obtain a high-quality injection product without cavities, it is necessary to make sure that the molten metal has sufficiently entered the gas discharge passage from the cavity and the gas has been discharged from the cavity, but before the falling sun flies out of the gas vent valve. It is necessary to tighten it promptly. As a result, the time required to close this valve needs to be extremely short, only 2 to 3 hsec. In addition, if it takes a long time for the valve to close after the command to close the valve is issued, you can move the operating position of the limit switch etc. a little closer to you depending on the expected operation, but the valve will slowly move upright. If the cavity is evacuated before injection, the valve will be close to closing even when the vacuum level is high, and the vacuum capacity will drop, making it impossible to obtain the desired vacuum capacity during injection. was there.

In particular, in conventional vacuum diagas, the opening/closing stroke of the valve is relatively long and the valve is tightened with a cylinder, so it takes less than 0.5 seconds to close the valve. It took several seconds, and because of this, the vacuum degassing was not performed satisfactorily. Furthermore, when the valve is slowly closed, even if the degree of variation in the valve's closing action is constant, the amount of variation when it is actually closed increases, and the stability of the vertical action of the valve also deteriorates. Therefore, as mentioned above, one important factor is how quickly the valve can be closed when a limit switch or other command is received during high-speed injection, but with conventional gas exhaust valves, this is not possible. , were not fully satisfied. The present invention aims to eliminate these drawbacks. During injection, the gas vent valve for the mold is opened and a large amount of gas in the cavity is discharged through the valve, and the above-mentioned gas is discharged during the forward movement of the injection cylinder. The valve is closed as quickly and reliably as possible in a predetermined position to prevent the molten material to be injected from coming out of the valve, and it is possible to reliably and easily obtain a high-quality, strong, and void-free injection product. This is how it was done.

To this end, in the present invention, a gas exhaust valve that can be opened and closed is provided in the gas exhaust path following the cavity provided between the molds or in the gas exhaust part of the cavity, and the valve stem of the valve is connected to a different outer flange. A stepped valve stem with a stepped valve stem, and a material such as a compression spring that applies a force in the direction of closing the valve is provided between the valve stem and a fixed part that slidably holds the valve stem, A rod is attached to the solenoid device so that it can move forward and backward, and a member is provided on the rod part that applies force in the direction of pressing the rod against the valve stem, and the rod is engaged with the stepped part of the valve stem to open the valve. so that the rod can be kept open, the solenoid device can be energized by the operation of an injection stroke detector during injection to retract the rod, and the gas in the cavity can be exhausted by the forward action of the molten metal being injected; The mold gas vent Hishitaka is constructed so that the valve is closed by the action of a solenoid device and members such as a compression spring when the gas has finished being discharged. Next, the present invention will be explained in more detail with reference to embodiments shown in the drawings.

Figures 1 and 2 show one embodiment of a die-casting machine, in which 1 is a fixed plate, 2 is a fixed mold, 3 is a movable mold, and 4 is a die-casting machine.
is the cavity, 5 is the injection cylinder, 7 is the injection cylinder 5
This is a striker attached to an injection plunger 6 that is integrally attached to the piston rod.

The movable mold 3 is fixed to the movable platen 8 side, and the extrusion plate 10 slides toward the movable mold 3 via a rod 9 operated by an extrusion cylinder (not shown) provided on the movable platen 8 side. This extrusion plate 101 has a plurality of extrusion pins 11 fixed thereto, is slidably fitted into the movable mold 3, and serves to extrude the injection molded product. .

On the other hand, in this embodiment, a gas venting device 12 is attached to the upper separation surface of the movable mold 3.

This degassing device 12 has a structure as shown in an enlarged view in FIG. The gas venting device 12 has a povet-shaped valve 14 provided in a gas discharge passage 13 that is continuous with the cavity 4, and a valve thread 15 of this valve 14 is connected to a fixed member 16 fixed to the movable mold 3 side to open the mold. It is iron-coupled so that it can slide freely in the direction.
A small diameter portion 17 is formed on the movable mold 3 side of the valve holder 15, and by forming this small diameter portion 1.7, a stepped portion 18 is formed in the middle of the valve holder 15. The povet-shaped valve 14 has a short stroke and is ideal for increasing the gas passage area, shortens the operating time and can be closed quickly, and also provides a good seal so that the molten metal does not flow through the valve stem. You can prevent it from entering the 15 side. Furthermore, since the valve 14 can be tightened in the gas venting direction, tightening is easy. A nut-shaped spring receiver 19 is fixed to the end of the valve stem 15 on the side of the movable mold 3, and a compression spring 20, which is a type of elastic body, is inserted between the spring receiver 19 and the rear surface of the fixed member 16. It is loaded with bullets and is constantly biased to pull the valve 14 toward the movable mold 3 side.

As is clear from FIG. 2, the valve head 14a of the valve 14 is formed on the fixed mold 2 side and has a structure that it can be positioned in a recess 21 continuous with the gas discharge path 13, A closing portion 22 formed on the third mold dividing surface 3a side has a valve seat 22a and faces the recess 21.

This opening 22 is an exhaust port 23 formed on the movable mold 3 side.
The lotus is suitable. On the other hand, the upper end of the fixed mold 3 has a solenoid/
A rod 24 is fixed, and a rod 25 thereof is inserted into a through hole 26 formed in the fixing member 16, and further passes through the fixing part village 16 to a position where it can engage with the stepped part 18. It is coming. When the tip of the rod 25 is engaged with the stepped portion 18, the valve head 14a is carried into the recess 21, and the gas exhaust passage 13 and the exhaust port 23 are connected to the opening □ portion 22. It is maintained in a state where it is fully connected through the spring, and the compression spring is in a state where it is fully compressed. In addition, compression 'imitation 2
0 is a member that applies force in the direction of closing the valve 14, such as a tension spring installed at another position, a cylinder, or another member that uses gravity to pull the valve backward. You can also change the layers. Further, a spring receiver 27 that also serves as a stopper for regulating the lower limit of the rod 25 is provided in the middle of the rod 25, and the spring receiver 27 and the through hole 26
A compression spring 29 is connected between the boss 28 fixed to the open end of the
is rounded and constantly applies force to the rod 25 in the forward direction.

Therefore, if the solenoid 24 is energized in the open state shown in FIG. 2, the rod 25 will rise.
When the distal end of the valve holder 15 disengages from the attachment part 18 of the valve head 15, the valve 14 is quickly tightened by the action of the compression spring 20.

In this case, when the compression spring 20' is in the state where the valve 14 is sewn, the force that tightens the valve 14 is slightly weakened, but when the valve 14 is open, it is in the maximum compression state, so the force that tightens the valve 14 is reduced. This is extremely strong, which is much greater than the force with which the valve is tightened by a solenoid when the valve is directly tightened by the action of a conventional solenoid, and therefore the valve 14 can be tightened quickly. In addition, the compression spring 20
By using this, once the valve 14 is closed, it is possible to keep the valve 14 reliably closed until the valve 14 is opened by the action of the set pin 30, which will be described later. Furthermore, if the engagement is disengaged, the valve 14 becomes vertical, so the action of the solenoid 24 causes the rod 2 to
The valve 14 can be quickly tightened by simply moving the valve 5 by about one rib. Note that once the rod 25 is moved back and the valve 14 is closed, the solenoid 24 can be demagnetized. An IJ set pin 30 is fixed to the extrusion plate 10 in parallel with the extrusion pin 11 and facing the rear end of the valve shank 15.

The reset pin 30 is set so as not to contact the rear end of the valve stem 15 when the valve 14 is closed and the valve stem 15 is in a retracted state. By the way, the contact between the rod 25 and the mounting portion 18 of the valve shank 15 is not a direct contact by the rod 25, but may be an indirect contact via the steel ball 31 as shown in FIG. 3a. good.

Furthermore, the stepped portion 18 does not necessarily need to be provided only on the valve shank 14 itself, but may be provided on a part that moves integrally with the valve shank 14, for example, a nut-shaped spring receiver 19 as shown in FIG. 3b.
It can also be provided in In addition, the valve stem 15 may have a stepped portion 18 structure as shown in FIGS.
A groove or a hole into which the tip of the rod 25 can fit may be provided in a part of the valve ridge 15, or a protrusion may be provided on a part or the entire circumference of the valve ridge 15, and the tip of the rod 25 may be provided on the rear end surface of the protrusion. You may also try to guess the part.

In addition, in the present invention, the valve 14, such as the spring receiver 19,
Components other than the Benshin 14 itself that move in the same manner as
It shall be included in the valve stem.

On the other hand, an injection striker, such as a limit switch 32 or a proximity switch, which serves as an injection stroke detector during injection, is placed at a position where the striker 7, which is integrated with the plunger 6, comes into contact with the striker 7. A limit switch 32 and the solenoid 24 are connected to a lead wire 33.
, 34, and a power source 35 is provided in the middle of the lead wire 33. In the state shown in Figure 1,
The limit switch 32 comes into contact with the striker 7 and turns OFF.
is in a state of Note that 36 is an injection sleeve and 37 is a molten metal. The reason why the solenoid 24 device directly connected to the limit switch 32 is used to close the gas exhaust valve 14 while the injection plunger 6 is moving forward is because the operating stroke of the solenoid 24 device is, for example, about one rib. The valve 1
This is because the time required for the closing operation of No. 4 can be extremely reduced, and the responsiveness is extremely good and the operation is quick.

In order to close the valve 14 during injection, it is necessary to adopt a driving method that satisfies these conditions, and the combination of the solenoid 24 and the compression spring 20 is most suitable for this purpose. Next, the operation of this embodiment configured as above will be explained.

First, as shown in Fig. 1, the fixed mold 2 and the movable mold 3
In the closed state, a predetermined amount of molten metal 3 is poured into the injection sleeve 36.
7 and turn on the injection start switch (not shown).

Then, the injection cylinder 5 operates, the plunger 6 moves forward, and the molten metal 37 is transferred from the injection sleeve 36 to the cavity 4.
Cast at low speed followed by high speed. As the plunger 6 moves forward, the striker 7 integrated therewith also moves forward, and the striker 7 comes off the limit switch 32, and the time when the cavity 4 is filled with molten metal and it escapes in the direction of the gas discharge path 13 inside the cavity. If set to , the solenoid 24 is energized at the same time the limit switch 32 is turned on, the rod 25 is attracted and retreats, the engagement between the tip of the rod 25 and the stepped portion 18 is released, and the valve 14 is closed. Retracted by the elastic force of the compression spring 20, the valve 14 closes the closing portion 22 and completely prevents the molten metal 37 from spouting out from the exhaust port 23. In this case, as described above, the solenoid 24
The engagement portion is disengaged by raising the valve 5 by just one height. At that time, the valve 14 is pulled backward by the action of the compression mimic 20, so the limit switch 32 issues a command to close the valve 14.
The valve 14 weaves in an extremely short time, for example, 3 hsec, until the spelling is completed. Since the gas in the cavity 4 has been completely exhausted before the valve 14 is vertically raised, there are no problems such as gas mixing into the product and the formation of cavities.

After the injection is completed and a predetermined cooling time has elapsed, mold sealing is performed, the extrusion plate 10 advances, and the extrusion pin 11 extrudes the product, but at the same time, the reset pin 30 also advances and the valve holder 15 Push the rear end to move the valve 14 forward.

At this time, the current to the solenoid 24 has already been cut off, and the rod 25, which is given a force in the forward direction by the compression spring 29, is in a state of engagement with the stepped part 18, and the valve 14 is in the state of being engaged with the stepped part 18. 22 is reset to the open state and is in a state of waiting for the next molding operation. Note that when extruding the product, if the amount of protrusion of the valve 14 by the reset pin 30 is set to be larger than in the reset state,
Cleaning of the 12 gas venting devices using the gas flow etc. becomes easy.

Figure 4 is for explaining another embodiment of the present invention.
The same parts as those in Figures 1 to 3 are given the same reference numerals, and their explanations will be omitted.

This embodiment employs a structure in which the gas in the cavity is forcibly discharged by an exhaust device, which is a vacuum generating device, and a structure in which a gas venting device is used in combination.

That is, an exhaust pipe 38 is provided continuously to the exhaust port 23, a branch pipe 39 is provided in the middle of the exhaust pipe 38, and a lid 40 that can be opened and closed is provided at the closed end of the branch pipe 39.

A Ryuji switching valve 43 is provided in the middle of a pipe 42 connecting the exhaust pipe 38 and the exhaust device 41. The limit switch 32
A limit switch 44, which is a stroke detector for a vacuum start command, is provided at a position apart from the plunger 6 in the backward direction. The limit switch 44 is located at a position where the limit switch 44 is released from contact with the striker 7 and turned ON immediately before switching from an initial low-speed injection to a high-speed injection in a normal injection molding method. This limit switch 44 is connected to the power supply 35 and the lead wire 4
6, and a timer 46 is disposed in the middle of this lead wire 45.
A switch 47 that is turned off by the action of a timer 46 is disposed between a part of the solenoid 43a of the electromagnetic switching valve 43 and a part of the lead wire 33 is connected to the solenoid 43a of the electromagnetic switching valve 43. It is connected to the port 43a. Next, the operation of this embodiment configured as above will be explained.

Before starting injection, limit switches 32, 4
4 is in the OFF state, molding is performed in this state, the gas venting device 12 is in the open state, and the electromagnetic switching valve 43 is in the OFF state.
It is in FF state.

In this state, first, low-speed injection is performed. The injection cylinder 5 is activated, the plunger 6 moves forward, and the molten metal 37 begins to be supplied into the cavity. Eventually, limit switch 4
When the contact between the striker 4 and the striker 7 is removed and the state is just before the start of high-speed injection, the limit switch 44 is turned on, the electromagnetic switching valve 43 is also turned on, and the gas in the cavity 4 is forced out by the exhaust device 41 via the piping 42. is discharged. At this time, the lid 40 is closed due to negative pressure.
In this state, the limit switch 32 is still in the OFF state, the valve 14 is in the open state, and vacuum suction is continued. When the limit switch 44 is turned ON, the timer 46 starts counting, and soon, the molten metal 37 is supplied into the cavity by the high-speed advance of the plunger 6, and as the molten metal 37 advances, the remaining liquid that has been discharged by the action of the exhaust system 41 is removed. Even a very small amount of gas is discharged to the outside through the valve 14.

When the falling sun 37 reaches the gas exhaust path 13, the contact between the striker 7 and the IJ mitt switch 32 is broken, so the solenoid 24 is activated, the compression spring 20 is activated, and the molten metal 37 reaches the valve 14. Before, valve 14 closes quickly. Thereafter, the timer 46 counts out and the switch 47 is turned off, so that the electromagnetic switching valve 43 is also turned off, and the vacuum source is cut off. In this way, the gas is forcibly discharged by vacuum suction, so that no gas in the cavity is mixed into the product, making it possible to obtain a good injection product.

After injection molding, the mold is opened, the extrusion pin 11 extrudes the product, the plunger 6 retreats, the limit switches 32 and 44 are turned off, and the timer 46 is reset to wait for the next molding operation. state.

5 and 6 illustrate the next embodiment of the present invention, and in the figures, the same or corresponding parts as in the previous embodiment are denoted by the same reference numerals.

In this embodiment, unlike the embodiments described above, a gas venting device 12 is attached to the fixed mold 2 side.

A protrusion 14b is formed at the tip of the valve 14. The purpose of providing this protrusion 14b is to increase the contact area of the valve 14 with the molten metal, thereby making it easier for the molten metal to bite.

The principle of operation is similar to that of the previously described embodiment, but the manner in which the valve opens is different.

That is, FIG. 5 shows the valve 14 in an open state, and FIG. 6 shows the valve 14 in a closed state.

As shown in FIG. 6, when the valve 14 is closed and the molten metal 37 enters the gas discharge path 13 and the recess 21 and fills the outside of the valve 14, as the molten metal 37 cools, the valve 1
It begins to adhere to the outer surface of 4. At this time, the metal is reliably bitten into the valve rocker portion 14a of the valve 14 whose surface area has been increased by providing the protrusion 14b. The mold is opened in this state, but at this time, since the cooled solidified metal is biting into the valve head 14a, the valve 14 is moved toward the movable mold as the movable mold moves, and the compression spring 20 is compressed, the lower end of the rod 25 engages the stepped portion 18, and the valve 14
becomes open.

If such a structure is adopted, the degassing device can be reset by the mold opening operation without requiring a reset pin. FIG. 7 illustrates still another embodiment of the present invention, in which a separate actuator 48 is provided for resetting the valve 14. When such a structure is adopted, assuming that the distance indicated by the symbol d in FIG. 7 is the reset distance, the valve 14 can be made to protrude beyond the reset distance d by operating the actuator 48. Device 1
This is extremely advantageous for cleaning No. 2.

In addition, the shape of the valve head 14a of the valve 14 is such that a parallel portion 14c is provided at the central outer circumference in all directions of the axis.
In order to increase the surface area that comes into contact with the molten metal in step a and make it easier for the cooled metal to bite, it is possible to forcibly reset the valve 14 when resetting it, as in the embodiment shown in FIGS. 5 and 6. Therefore, it is not necessary to use the actuator 48 for resetting.

In addition, when using the actuator 48 for reset, the actuator 48 can be provided outside the fixed platen 1 instead of being provided in the fixed mold 2 part by passing the valve 15 through the fixed platen 1.

Incidentally, in each of the above-mentioned embodiments, an example was explained in which a gas venting device was provided in a part that was substantially continuous with the gas exhaust at the end of a fixed mold or a movable mold, but the mounting position of the gas venting device was It is not limited to such a part, and it may be provided in any part of the fixed mold or the movable mold, for example, it may be provided in the central part of the mold. Depending on the structure of the mold, it may be difficult to provide a solenoid on the top or surface of the mold because the core is attached all around the mold. In such a case, a structure as shown in FIG. 8 may be adopted.

In the embodiment shown in FIG. 8, the degassing device is provided in the center of the movable mold.

Even in FIG. 8, the same reference numerals are given to the same or corresponding parts as in the above-described embodiment, and the explanation thereof is omitted. In this embodiment, an exhaust pipe 49 is provided passing through the movable platen 8 and the movable mold 3, and a fixed part village 16 is provided facing the dividing surface of the movable mold 3 and integrated with the exhaust pipe 49. Fixed member 1
A part of the valve member 15 of the valve 14 is freely attached to the valve 6 via a bearing 16a.

A seat 22a is provided at the tip of the fixing member 16, and the fixing mold 2
A recess 21 in which the valve 14 is located is provided on the side, and a bearing 16 is provided on the side.
A plurality of through holes 16b are formed around a. On the other hand, another fixed member 50 connected to the exhaust pipe 49 is provided on the movable platen 8 side, and a technical air port 51 is formed in a part of the fixed member 50 . This fixed member 5 Kawakoben-sama 15
A stepped portion 18 is slidably supported on the shaft, and a solenoid 24 having a rod 25 is attached at a position where it can engage with the stepped portion 18. Further, an actuator 52 for driving the valve stem 15 is also provided in the fixed part village 50. Note that instead of this actuator 52, the first,
A set pin as shown in Figure 2 can also be used. Since this embodiment is configured as described above, the valve 14
When the valve 14 is open, the gas in the mold cavity can be exhausted through the exhaust pipe 49, and if the solenoid 24 is operated through a control mechanism such as a combination of a striker and a mitt switch, the valve 14 is opened. The valve 1 can be closed quickly to prevent the molten metal from spewing out.Furthermore, by operating the actuator 52 or the set bin, the valve 1 can be closed quickly.
4 can be made to protrude to facilitate cleaning.

Note that when the valve 14 is provided on the cavity surface, the structure must be such that the surface of the square head forms part of the inner surface of the cavity when the valve is closed. As is clear from the above description, according to the present invention, since the structure as described in the claims is adopted, the gas in the cavity can be discharged in large quantities and sufficiently through the gas discharge valve during injection of molten metal. In addition, the gas discharge valve can be automatically closed just before the end of injection, completely preventing the molten metal from coming out of the mold. Furthermore, since the gas in the cavity can be reliably and easily discharged, a high-quality injection product that does not contain gas and has no cavities can be reliably and easily obtained. In addition, in the present invention, in order to close the gas exhaust valve, a solenoid, a valve release valve having a stepped portion engaged with a rod that retreats by the action of the solenoid, and a compression spring that biases a force in the direction of closing the valve are used. Since we used a member such as the rod, the engagement between the rod and the valve stem is enough to keep the valve stem in place, and the rod only needs to be moved back a little by one skin due to the action of the solenoid. can be tightened by the action of a material such as a compression spring.

Therefore, the movement stroke of the rod by the solenoid can be extremely short, and the engagement between the rod and the valve shank can be quickly disengaged. Since the valve can be pulled, the valve can be quickly closed after receiving a command to close the valve. moreover,
The valve is tightened using a compression spring, etc., and once the valve is tightened, it can be kept securely closed until the valve is opened by the action of a reset pin, etc., so that intermittent hot water does not come to the valve part. Even if the valve is opened vertically, it will not open.
Therefore, the setting sun will not penetrate beyond the valve head, and the valve will not malfunction.

Of course, even if the solenoid flaps, it has no effect. In addition, the gas exhaust valve can be quickly closed while the injection plunger is moving forward at high speed, so gas can be discharged reliably and easily. Stroke detection can also be used to issue an operating command to the solenoid device while the injection plunger is moving forward at high speed. It is easy to adjust the position of the device and the timing of operation instructions. In addition, when the present invention is used in combination with the vacuum die gas method, the trowel can easily obtain a predetermined vacuum capacity by closing the valve very quickly. Moreover, by quickly kneading the valve, stability of the valve kneading operation can also be obtained. Note that at the start of operation, injection is usually performed only at low speed in order to raise the mold temperature and protect the mold, but at this time the inertia of the rising sun is weak, so the valve does not close and the valve does not close. There is a risk of molten metal getting into Ayabe.

However, in the present invention, a solenoid is used, so in such a case, the valve can be closed in advance by activating the solenoid using a changeover switch or the like.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing one embodiment of the present invention, Fig. 2 is an enlarged sectional view of the degassing device portion of Fig. 1, and Figs. FIG. 4 is a longitudinal sectional view showing another embodiment of the engagement structure of the stepped portion, FIG. 4 is a longitudinal sectional view showing another embodiment of the present invention, and FIGS. 5 and 6 are further embodiments of the present invention. FIGS. 7 and 8 are longitudinal sectional views showing examples of the valve open state and the valve closed state, respectively, showing further different embodiments of the present invention. 1...Fixed plate, 5...Fixed mold, 3.
...Movable mold, 4...Cavity, 5...Injection cylinder, 6...Plunger, 7...Silica, 8...Movable plate, 11... ... Press pin, 12 ... Gas venting device, 13 ... Gas discharge path, 14 ... Valve, 15 ... Valve twill, 18 ... Stepped part,
20, 29... compression spring, 23, 51...
...Exhaust port, 24... Solenoid, 25... Rod, 30... Reset pin, 32, 44...
Limit switch, 41...Exhaust device, 48...
…Actually evening. Figure 2 Vertical Figure 3 Figure 5 Figure 6 Rudder Figure 7 Ship

Claims (1)

[Claims] 1. A gas exhaust valve that can be opened and closed is provided in the gas exhaust path following the cavity provided between the molds or in the gas exhaust part of the cavity, and the valve stem of the valve is a stepped valve stem with different outer diameters. A member such as a compression spring that applies force in the direction of closing the valve is installed between the valve stem and a fixed member that slidably holds the valve stem, allowing the solenoid device to move the rod back and forth. mounting, a member is provided on the rod portion that applies a force in a direction to keep the rod pressed against the valve stem, so that the rod can be engaged with a stepped portion of the valve stem to keep the valve in an open state;
The operation of the injection stroke detector during injection excites the solenoid device so that the rod can be retracted, and the forward action of the molten metal being injected discharges the gas in the cavity, and the gas discharge is completed. A gas venting device for molds that is configured to close the valve by the action of a solenoid device and components such as a compression spring when the mold is filled.