JPS6234656A - Device for venting gas in metallic mold - Google Patents

Abstract

PURPOSE:To assure a normal operation, to stabilize a pouring stage and to improve productivity by having a mechanism to freely open and close, as desired, a valve disk which is freely movable upward and downward with regard to a spool and providing a detector for valve closure. CONSTITUTION:A spool 8 is preliminarily raised up to an initial attitude position and is detached from an insertion holes 9 of cradles 10, 10' in the pouring stage to a cavity 7. The spool 8 descends to fit the bottom end thereof into the holes 9 at the point of the time when the pouring stage is started. At the same time, the valve disk 17 is pressed to a valve disk receiving part 41 of the cradles 10, 10' to set a device 1 for venting gas in a metallic mold to the mold 2. The 1st three-way valve 37 is then operated to supply 36, 33 the working air under a set pressure from a compressed air source 39 to the 1st cylinder chamber 23 to energize a piston 22 upward. As a result, a recess of a valve stem 18 retreats a steel ball 28 to unlock the valve disk 17, then the valve disk ascends and the top edge of the disk 17 contacts with a valve seat 31 at the bottom end of the spool 8 via the valve stem 18 thereby fully closing a gas vent passage 20 and interrupting the communication with the cavity 7 through a bypass passage 32.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The disclosed technology belongs to the technical field of degassing devices in molds used in die casting and the like.

<Summary of the gist> Accordingly, in this invention, a valve body that can be freely raised and lowered with respect to a spool faces a gas handling groove connected to a die cast 1 to a cavity in a mold for casting, etc. The present invention relates to an in-mold degassing device in which a gas central passage formed between a connected valve stem and the spool and the gas handling groove are connected via a bypass passage via a valve seat, and in particular, The in-mold gas exhaust device has a mechanism that allows the valve body to open and close at will using a type actuator, etc., and is equipped with a valve closing detector such as a proximity sensor to confirm the normal closing operation of the valve body. This is such an invention.

<Prior art> In general, die casting and injection molding are technologies that are widely used when mass producing products of the same shape, and when these manufacturing technologies are used, molten metal or Since molten resin (hereinafter referred to as molten metal) is filled at high speed, if the gas in the cavity is left to naturally vent, the replacement of molten metal with gas will be incomplete and a gas entrainment phenomenon will occur, resulting in the so-called bubble nest defect. This may result in an unhealthy product.

To deal with this, as disclosed in Japanese Patent Application Laid-Open No. 56-47257, a gas vent groove connected to a cavity in the mold is connected to a predetermined suction device to reduce the pressure inside the cavity. A means has been devised to forcefully exhaust the gas.

When the above-mentioned gas is forcibly exhausted, an in-mold gas spreading device is disposed at the end of the gas vent groove and connected to a suction device.

Thus, in the in-mold gas actual device, the valve body, which can be raised and lowered with respect to the spool, is pressed against the valve body receiving portion formed at the end of the gas vent groove of the mold, and is connected to the valve body. A gas handling passage formed between the valve stem and the spool is connected to the gas vent groove by a bypass passage through the valve seat.

Since the mass of the gas in the cavity is small, even if it collides with the valve body, the inertial force is small. Therefore, the state of contact between the valve body receiving part and the valve body is maintained without raising the valve body. The gas is forcibly exhausted to a suction device via a bypass passage and a gas handling passage.

Furthermore, when the molten metal ( ) collides with the valve body after the gas is forcibly exhausted, the mass of these molten metals is large, so the valve body is pushed up by its inertia and hits the valve seat formed on the spool. The bypass passage and the JJ Su enemy passage were cut off.
Molten metal is prevented from flowing into the gas handling passage.

<Problems to be Solved by the Invention> However, in the above-mentioned conventional in-mold gas device, when setting the valve body in the valve body receiving part of the gas i & groove of the mold, If a foreign object such as powder or dirt gets caught in the gap between the holes, the inertial force of the molten metal will not be able to push up the valve body due to the large frictional resistance due to the presence of the foreign object, and the actual gas device in the mold will not work. There was a drawback that the valve was kept open and the molten metal flowed into the gas sump passage through the bypass passage.

Furthermore, as a result, the process of pouring molten metal becomes unstable, resulting in lower productivity and lower product yield.

The purpose of this invention is to solve the problems of the mold gas venting device based on the above-mentioned prior art, and to
An excellent in-mold degassing device that ensures that the IP;L device operates reliably, performs molding as designed, and facilitates maintenance, benefiting molding technology applications in various manufacturing industries. This is what we aim to provide.

<Means/effects for solving the problems> In order to solve the above-mentioned problems, the structure of the present invention, which is based on the above-mentioned claims, is to solve the above-mentioned problems. The valve body, which is movable up and down, is brought into contact with the valve body receiving part in the mold, and the central gas passage formed between the valve stem connected to the valve body and the spool is bypassed through the valve seat. After the in-mold gas venting device is set in the mold by connecting it to the gas venting groove through a passage and allowing the valve body to open and close at will using a hydraulic actuator, etc., before injecting the molten metal into the cavity. The valve body is raised by applying a predetermined force using the hydraulic actuator, etc., and the proximity sensor detects when the valve body contacts the valve seat and is fully opened, and the molten metal is poured. During the process, we confirm that the mold gas device operates reliably, prevent molten metal from flowing into the mold gas vent device, stabilize the pouring process, and improve productivity. , technical measures have been taken to improve product yield.

<Embodiment - Configuration> Next, one embodiment of the present invention will be described below based on the drawings.

Reference numeral 1 denotes an in-mold gas venting device, which constitutes the gist of the present invention, and is shown in this embodiment as a mode in which it is set in a mold 2 used for die-casting.

In the mold 2, a fixed insert 5 and a movable insert 6 are sandwiched between a fixed main mold 3 and a movable main mold 4, forming a cavity 7 of a predetermined shape. A pedestal 10.10' is provided above the insert 5 and the movable insert 6 in which an insertion hole 9 for the spool 8 of the in-mold gas device 1 is formed.

A stand 11 is erected and fixed at a predetermined portion of the movable main mold 4, and a hydraulic cylinder 13 is mounted on the upper frame 12 of the stand 11.
is attached with the cylinder rod 14 facing the insertion hole 9, a rod end block 15 is fixed to the tip of the cylinder rod 14 with a bolt 16, and a spool 8 is integrally extended downward below the rod end block 15. .

A valve guide 19 is provided at a predetermined location approximately in the center of the spool 8 to support the valve stem 18 integrally formed with the valve body 17 at the bottom so as to be slidable up and down. Inside, a cylinder chamber is formed on the upper side of the valve guide 19, and a gas I friend passage 20 is formed on the lower side surrounded by the valve stem 18, the valve guide 19, and the spool 8. It is connected to a predetermined suction device (not shown) via an opening 21 formed on the side.

A piston 22 screwed onto the base of the valve stem 18 connects the first cylinder to 23 on the lower side and the second cylinder on the upper side.
The piston 22 is divided into cylinders 24, and the piston 22 is slidable in the valve guide 19 via a compression spring 25 having a predetermined spring constant to urge the valve body 17 upward.

Note that 26 is a spacer having a predetermined height, and is disposed on the valve guide 19 to prevent excessive deflection of the compression spring 25. A compression spring 29 is inserted into the threaded hole 27 with the steel ball 28 inside, and a bolt 30 is screwed into the valve stem 18.
The valve body 1 is pressed against a recess (not shown) on the side of the valve body 1, and resists the upward bias by the compression spring 25 provided on the valve guide 19.
It is designed to be locked to maintain the open state shown in FIG.

Therefore, the molten metal presses the valve body 17 from below and the valve stem 1
8 is raised, the steel ball 28 is retreated to the left in FIG. 1 by the four parts of the valve stem 18 against the compression spring 29, and the valve body 1
8 is unlocked, the piston 22 is urged by the compression spring 25 and moves upward, and the valve body 17 is seated on the valve seat 31, and the gas handling passage 20 is connected to the cavity 7 via the bypass passage 32. Communication is cut off.

Furthermore, a first air circulation hole 33 communicating with the first cylinder 23 and a second air circulation hole 33' communicating with the second cylinder 24 are bored at a predetermined portion on the upper side of the spool 8. The proximity sensor 34 as a valve closing detector is connected to the second
a first connection port 36 that is loosely inserted into the air circulation hole 33', is fixed to the side surface of the spool 8 via a backing plate 35, and communicates with the first air circulation hole 33 formed in the backing plate 35;
and a second connecting hole 36 communicating with the second air circulation hole 33'.
' are connected to a compressed air source 39 via the corresponding first three-way valve 37 and second three-way valve 38, and are further connected to the first connection port 36.
A pressure switch 40 is branch-connected between the first three-way valve 37 and the first three-way valve 37 .

The lower end of the spool 8 is connected to the pedestal 10.1 of the mold 2.
As shown in FIG. It is fitted into the body receiving part 41 through a clearance that allows it to be fitted in and removed.

Further, a gas passage 42 formed on the outside of the valve body 17 is connected to the gas handling passage 20 in the spool 8 via a bypass passage 32, and a gas passage 42 formed on the outside of the valve body 17 is connected to the gas handling passage 20 in the spool 8. The formed gas central portion 43 is connected to a gas devitrification 44 formed between the fixed insert 5 and the movable insert 6 and communicated with the cavity 7.

Further, the gas passage 42 and the gas central portion 43 are connected via a bypass passage 32 having a predetermined shape, as shown in FIG.

Note that 45 is a guide rod, which guides and supports the rod end block 15 as it moves up and down.

<Embodiment - Effect> In the above-described configuration, when pouring molten metal into the cavity 7 by an injection plunger (not shown), the spool 8 is raised to the initial posture position by the hydraulic cylinder 13 before pouring, and the spool 8 is raised to the initial posture position by the pedestal 10.10'. has been removed from the insertion hole 9.

Then, at the timing of transitioning to the pouring process, spool 8
is lowered by the hydraulic cylinder 13 and its lower end is inserted into the insertion hole 9.
At the same time, the valve body 17 is brought into contact with the valve body receiving portion 41 of the pedestal 10.10', and the mold gas exhaust device 1 is set in the mold 2.

Next, the first three-way valve 37 is operated, and working air at a set pressure is supplied from the compressed air source 39 to the first cylinder to 23 through the first connection port 36 and the first air circulation hole 33, and the piston 22 is forced upward, and the concave portion of the valve stem 18 is pressed against the steel ball 28.
The lock is released by retracting the valve, and the valve body 17 is raised and the valve stem 1
The upper edge of the valve body 17 is located at the lower end of the spool 8 through the valve seat 3
1, the central gas passage 20 becomes fully closed, and communication with the cavity 7 via the bypass passage 32 is cut off.

With the above-described valve closing operation, the piston 22 fixed to the base of the valve stem 18 also rises as described above, and as a result, the proximity sensor 34 is turned on, confirming the valve closed state.

If the proximity sensor 34 does not operate for a set period of time, the valve will not be closed, and a control panel (not shown) will sound an alarm to perform an abnormality check and reset.

At this time, the pressure switch 40 is used to check whether the working air is being supplied normally within the set pressure range, and if the pressure is outside the set pressure range, the pressure switch 40
It is electrically connected and transmitted to a control panel (not shown) to sound an alarm, indicate an abnormality in the in-mold gas venting device 1, and reset to a normal state.

In this embodiment, both the pressure switch 40 and the proximity sensor 34 are ON and normal, and the pressure switch 40 is ON.
If the proximity sensor 34 is OFF, it is abnormal.

Note that when the pressure switch 40 is OFF, an abnormality such as a hose trouble is detected.

Furthermore, as described above, as soon as the proximity sensor 34 confirms that the valve body 17 is normally closed, the first three-way valve 37 and the second three-way valve 37 are closed.
The three-way valve 38 is switched by a relay to connect the compressed air source 3
9 is supplied to the second cylinders 24 through the second connecting hole 36' and the second air flow hole 33', causing the piston 22 to move downward against the compression spring 25, thus causing the valve to close. The body 17 is lowered, and the valve body 17 is placed in the valve body receiving part 41.
As a result, the gas handling passage 21 is fully opened and connected to the cavity 7 via the bypass passage 32, completing preparation for the next process, the pouring process.

After that, similarly to the conventional aspect, an injection plunger (not shown),
Then, the suction device operates, and the molten metal is poured into the cavity 7, and the gas in the cavity 7 flows through the gas handler 44, 43, the bypass passage 32, and the bypass passage 32, as shown in FIG.
A gas passage 42 between the valve body 17 and the valve body receiving portion 41, and
The gas is sucked into the suction device via the gas vent passage 20.

Therefore, the gas in the cavity 7 is completely exhausted from the cavity 7 by the push-pull action of being pressed by the pouring metal and being sucked by the suction device.

In this process, the gas has a small inertia, so the gas handler 33,
It flows through each winding passage such as the bypass passage 32 without difficulty.

After that, when the subsequently poured molten metal flows through the gas handler 44, 43 and collides with the lower surface of the valve body 17, the valve body 17 compresses the air in the second cylinder to 24 due to its inertia and is pushed up. The upper edge of the valve body 17 is brought into contact with the valve seat 43, and the bypass passage 32, the gas passage 42, and the temporary gas passage 20 are shut off by the valve body 17, and as a result, the molten metal flows into the gas handling passage 2.
It never flows to 0.

However, as described above, before entering the pouring process, the spool 8 is lowered by the hydraulic cylinder 13, its lower end is fitted into the insertion hole 9, and when the in-mold degassing device 1 is set in the mold 2. , the valve body 1 between the valve body 17 and the valve body receiving portion 41
If foreign matter such as dust or dirt gets caught in the clearance that allows the valve body 17 to be inserted and removed, the valve body 17 may open r! j1111J
In the event that there is a risk of interfering with the operation, even if the first three-way valve 37 is activated and working air at the set pressure is supplied from the compressed air source 39 to the first cylinders 23. , the pressure of the working air cannot raise the piston 22 due to the frictional force of the wedge in the clearance, the valve body 11 is maintained in the valve open state, and therefore the proximity sensor 34 is maintained in the OFF state. An interlock is activated via the control panel which is electrically connected in a predetermined manner, and progress to the next step, the pouring step, is stopped.

Then, as mentioned earlier, the setting time of the proximity sensor 34 is
An alarm sounds due to the FF state, and a reset is performed by removing foreign matter during maintenance.

As mentioned above, before starting the process of pouring metal into the cavity 7, the operating state of the in-mold gas venting device 1 is confirmed in advance, and if it is operating normally, the process proceeds to the pouring process, and if there is an abnormality, the process proceeds to the pouring process. By stopping the progress to the pouring process, the molten metal is prevented from flowing into the gas vent passage 20 of the in-mold gas t& device 1, making it possible to maintain a stable pouring process and improve productivity. As a result, the product yield is improved, and maintenance of the in-mold gas recovery device 1 is also facilitated.

<Other Embodiments> It goes without saying that the embodiments of the present invention are not limited to the above-mentioned embodiments. For example, the mechanism for opening and closing the valve body as desired may be a gas type actuator other than a hydraulic actuator, or , it may be an electric type, or it may be other than an actuator, and the valve closing detector may be a contact type such as a limit switch other than a proximity sensor. It is.

Of course, the mold to which the in-mold gas actual device is used may be a mold used in injection molding.

<Effects of the Invention> As described above, according to the present invention, the valve body, which is movable up and down with respect to the spool, faces the gas vent groove connected to the cavity in the mold, and is The gas handling passage formed between the valve stem and the spool is connected to the gas vent groove by a bypass passage via the valve seat, and a valve closing detector is provided to confirm the valve closing state. By attaching the molten metal to the cavity, before pouring molten metal into the cavity, it is necessary to check in advance whether the valve body is operated as designed by the above-mentioned operating mechanism, that is, to check whether there is a gap between the valve body and the valve body receiving part. It is possible to use a valve closing detector to check whether or not any foreign substances such as these have intervened and prevented valve closing. The normal operation of the temporary equipment is guaranteed, the pouring process is performed extremely stably, the productivity is improved, and the product yield is also improved.

Furthermore, by properly operating the in-mold gas device during the pouring process, molten metal is reliably prevented from flowing into the gas passage of the in-mold degassing device, and maintenance is therefore extremely easy. The excellent effect of becoming Qin.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a general sectional view, and FIG. 2 is a partial sectional view of a gas handling system. 8... Spool, 17... Valve body, 2... Mold, 7... Cavity, 43.44... Gas vent groove, 18... Valve stem, 20... Gas handling passage , 31・
...Valve seat, 32...Bypass passage, 1...In-mold gas venting device, 34...Valve closing detector

Claims (1)

[Claims] The valve body, which can be raised and lowered relative to the spool, faces a gas vent groove connected to a cavity in the mold, and the gas vent passage formed between the valve stem and the spool and the gas vent groove are connected to the valve seat. The in-mold gas venting device is connected to the in-mold gas vent via a bypass passage, and the in-mold gas venting device is characterized in that it has a mechanism that allows the valve body to open and close as desired, and is also equipped with a valve closing detector. Device.