JP2649723B2 - Method and apparatus for applying release agent to contact surface of molten metal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention applies soot for improving mold releasability to a molten metal contact surface such as an injection sleeve for various castings, a plunger end surface, or a mold cavity. The present invention relates to a method and an apparatus for applying a release agent to a molten metal contact surface.

[Prior art] In various castings and forgings, such as die casting, squeeze casting, and molten metal casting, when the molten metal comes into direct contact with the molten metal contact surface such as the inner surface of a mold cavity or an injection sleeve and an end surface of a plunger, the product from the die is removed. Prior to casting, a mold release agent is applied to these molten metal contact surfaces because the releasability is deteriorated and the plunger tip does not move smoothly.

Conventionally, for example, water-soluble Hitasol (trademark) has been used as this type of release agent. However, since this type of release agent is water-soluble, the temperature of the surface to which it is applied is 100 ° C.
In addition to the problem of being restricted to a low temperature of about 250 ° C, the amount of adhesion varies depending on the temperature of the coated surface, and the conditions are not stable, it is necessary to water-cool to shorten the cycle time, and the limit of the shortening There is a problem that the cycle time is extended. Also, since the main component of the release agent is crystalline graphite in which water is solubilized, the thermal conductivity is large and the heat retention is not good, and the molten metal is easy to cool, so that the run of the molten metal may be deteriorated. If the concentration is increased to improve the heat retention, there is a problem that the spray nozzle is easily clogged and the conditions are not stable.

Therefore, the present applicant has proposed an injection method using a molding machine disclosed in JP-A-61-99551. According to this method, a lubricant or a release agent is applied to a contact surface of a molten metal, a burner is applied thereon, and the molten metal is supplied, and then mold clamping and injection are performed. Compared to the case of only the above, the heat retention is improved, the time required for the molten metal to solidify is increased, and the running of the molten metal is improved, not only improving the quality of the product but also significantly increasing the amount of gas generated. There was an effect of decreasing.

[Problems to be Solved by the Invention] However, in such a conventional apparatus for applying a soot or a mold release agent to a contact surface of a molten metal, since the structure is open between the spray nozzle and the application surface, Soot or mold release agent scatters around and soils workers, or inhales it, making it difficult to maintain a good working environment,
The spray section is enlarged and complicated, and the piping is turbulent, which is not preferable in terms of management. In addition, the release agent, water, etc. dripped, the inside of the factory became dirty, and the environment was poor due to steam, etc., which was a problem in environmental hygiene.

[Means for Solving the Problems] In order to solve such a problem, in the present invention, a release agent application device having an ignition device is brought into contact with a member having a molten metal contact surface in a sealed state, In this state, a mixed gas comprising gas and air is supplied from the mixed gas supply device to the space having the molten metal contact surface, and the space is filled, and the mixed gas is incompletely burned by the ignition device soot. Generating a soot and attaching the soot to the molten metal contact surface, and burning the mixed gas supplied from the mixed gas supply device into the space having the molten metal contact surface to generate soot, and applying the soot to the molten metal contact surface. A mold release agent application device having a cylindrical connection portion having a connection port provided on one side of a cylinder so as to be connectable to an inlet portion of a space having the molten metal application device, and the other end having a bottom portion. To A piston is provided in the cylinder so as to be movable in the axial direction of the cylinder, an ignition plug for burning the mixed gas is disposed between the forward end position of the piston and the connection port, and a discharge port for the combustion gas is provided on the ignition plug. The piston is provided on a part of the outer peripheral surface of the cylinder between the forward limit position and the backward limit position of the piston behind the position, and the piston movable between the front and the rear of the discharge port position is movable in the cylinder. One end of the return means for returning the piston after ignition is provided between the piston and the bottom on the bottom side, and the piston is fixed on the other end of the return means on the top side.

[Operation] In the state of mold clamping, after setting and connecting the release agent application device to the injection device and the mold device, acetylene gas and air are supplied from the mixed gas supply unit, and the mold cavity is connected to the cylinder. The mixed gas filled in the space between the head, cylinder and injection sleeve is sparked by the spark plug and incompletely combusted, soot is generated and adheres evenly to the molten metal contact surface such as the mold cavity and injection sleeve. Can be done easily. Therefore, the releasability is improved and seizure and prevention of deformation of the product can be prevented.

[Embodiment] In this embodiment, an embodiment in which the present invention is applied to soot application to a mold cavity of a die casting machine is shown. FIG. FIG. 2 is a schematic configuration longitudinal sectional view showing another embodiment in the case of implementing a release agent application device.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

When the release agent application device is implemented, as shown in FIG. 1, the mold device portion 30 including the fixed platen 1 and the like at the uppermost stage, the release agent application device 31 at the intermediate portion, and the injection device 32 at the lowermost stage. And the combination of the mixed gas supply device 40 attached to the mold device unit 30.

First, the mold unit 30 located in the uppermost part area includes a fixed platen.
1, a fixed mold 2, a bolster 3, a tie rod 4, a movable mold 5, and a gas release valve 35. In the figure, a fixed die 2 is mounted on a top surface of a fixed plate 1 fixed on a floor foundation via a bolster 3, and the fixed plate 1 and an upper fixed plate (not shown) are fixed at four corners. A movable platen (not shown) on which a movable mold 5 is mounted is supported on the tie rod 4 connected by the brackets so as to be able to move up and down. Then, the fixed mold 2 and the movable mold 5
The mold is clamped by the lowering of the movable platen by the mold clamping cylinder, and a cavity is formed by the concave portion 2a of the fixed mold 2 and the convex portion 5a of the movable mold 5 by mold clamping.

On the other hand, the release agent applying device 31 located in the middle portion includes a cylindrical connecting portion 21, a cylinder 22, a piston 23, a spring 24, a first hydraulic cylinder 26, a second hydraulic cylinder 27, and a spark plug 28. At one end of the cylinder 22, a tubular connecting portion 21 is disposed in a T-shaped conductive manner, and the other end is a cylinder bottom portion 22a. An elastic spring 2 is provided in the space inside the cylinder 22.
4, the piston 23 is inserted, one end of the spring 24 is fixed to the cylinder bottom 22a, and the other end is fixed to the piston 23, and an external force is applied to the piston 23 from the cylindrical connecting part 21 as a pressing force. When energized, the piston 23 moves to the cylinder bottom 22
An exhaust port 25 that is pushed toward the a side and is formed at right angles to the body of the cylinder 22 and a route that is conducted to the top region of the cylinder 22 and the cylindrical connecting portion 21 are formed. This serves as an outlet for the mixed gas incompletely burned by the spark plug 28 provided in the top region. The position where the spark plug 28 is provided is not limited to the top region of the cylinder 22, but may be provided at the cylindrical connecting portion. A first hydraulic cylinder 26 is provided independently on the cylinder bottom 22a on the extension of the axis of the cylinder 22, and a piston 26a is provided at the center of the piston 26a movably introduced left and right into the first hydraulic cylinder 26. One end of the rod 26b is fixed at a right angle, and the other end is fixed to the aforementioned cylinder bottom 22a.
By supplying the pressure oil into the hydraulic cylinder 26, the T-shaped cylinder 22 and the cylindrical connecting portion 21 can be moved right and left as necessary. Further, a second hydraulic cylinder 27 is provided at the bottom of the first hydraulic cylinder 26 so as to be orthogonal to the axis of the first hydraulic cylinder 26.
When one end of a piston rod 27a that constitutes 27 is fixed at a right angle to the bottom of the first hydraulic cylinder 26 and the other end is fixed at a right angle to the piston 27b, and when hydraulic oil is supplied to the second hydraulic cylinder 27, the first The hydraulic cylinder 26, the T-shaped cylinder 22, and the cylindrical connecting portion 21 can move up and down at the same time.
Note that the release agent applying device 31 is mounted between the mold device unit 30 and the injection device 32 as necessary when soot occurs, so that the first hydraulic cylinder 26 and the second hydraulic cylinder 27 The conduits connected to the pressurized oil supply units 26c and 26d and 27c and 27d, respectively, are suitably flexible.

Further, an injection device 32 is provided on the bottom of the pit below the floor. The injection device 32 includes an injection device main body 33 and a tilting device 34. The injection device main body 33 includes an injection cylinder 6, a piston rod 8, a plunger 9, a coupling 10, a block 11, and a ram 1.
2, consisting of a detachable cylinder 13, an injection sleeve 14, etc.
Further, the tilting device 34 includes the tilting cylinder 16 and the piston rod.
Consists of 17 An injection cylinder 6 is pivotally supported upright and tiltable via a placket 7, and a plunger 9 having a plunger tip 9 a as a head is coaxially formed with a coupling 10 on a piston rod 8 which advances and retreats by hydraulic pressure. It is connected to. 11 is plunger 9 and coupling 10
And a pair of cylinders 11a formed therein, and a ram 12 implanted on the upper surface of the injection cylinder 6 and slidably fitted to the cylinder 11a. And a detachable cylinder 13 is formed, so that the block 11 is raised by feeding oil above the ram 12. A cylindrical injection sleeve 14 is fixed to the upper end of the block 11, and the plunger tip 9a is slidably fitted in an inner hole thereof. After the incomplete combustion of the mixed gas is performed by mounting the release agent applying device 31, the release agent applying device 31 is detached and the injection device 32 is operated. Cylinder 11
When pressure oil is supplied from a pressure oil supply port (not shown) to the upper part of the block a and the block 11 rises, the injection sleeve 14 also rises to the position shown by the dashed line in FIG.
Joined to. Reference numeral 15 denotes a gate provided between the joining end and the cavity. Reference numeral 16 denotes a tilting cylinder pivotally mounted on the base side. The working end of the piston rod 17 is pivotally mounted on the injection cylinder 6, and the piston rod 17 is hydraulically moved when the block 11 is lowered. By moving forward from the state, the injection cylinder 6 and the block 11, the injection sleeve 14, and the like are integrally tilted to the dashed line position in FIG. Then, the injection of the molten metal described below is performed at this tilt position. Reference numeral 18 denotes a stopper that regulates the injection cylinder and the like in the upright position.

Here, the mixed gas supply device 40 to the release agent application device 31 will be described. 1, a mixed gas supply device generally indicated by reference numeral 40 includes an electromagnetic switching valve 36, a needle valve 37 for acetylene gas, and a needle valve 38 for air. Further, acetylene gas A is guided to a connection port 37a to the acetylene gas needle valve 37 via a hose (not shown). This gas is a gas that generates soot as carbon having an amorphous structure called amorphous carbon by incomplete combustion at a low temperature of, for example, about 350 ° C., and includes methane gas, alcohol gas, propane gas, and butane gas. And so on. In addition, air is guided to a connection port 38a to the air needle valve 38 via a hose (not shown). Further, the electromagnetic switching valve 36 can be appropriately switched as needed, and when the mixed gas is supplied,
By switching the solenoid valve, a gas supply line is formed, the incomplete combustion of the supplied mixed gas ends, the next molten metal is supplied to the injection device 32, and the injection device 32 is operated to enter the cavity of the mold. When the molten metal is injected, an exhaust line is formed from the mold cavity to the exhaust line for degassing via the degassing valve 35. Here, the configuration of the gas vent valve 35 will be briefly described. Regarding the vent valve 35, Japanese Patent Application No. 61-278726 and Japanese Patent Application No. 61-2607
As is well known in No. 15, when a molten material is injected and filled into a cavity at high speed and high pressure in an injection molding machine such as a die casting machine, cavities may be generated in a product without exhausting gas in the cavity. In addition, a large amount of these gases can be removed in a short time while preventing the formation of nests in the product. This gas vent valve 35 has a gas vent groove communicating with the cavity, and a valve that slides in the axial direction at its end,
A bypass as a gas discharge passage that bypasses from the middle of the gas release groove to the side of the valve portion is provided on the separation surface portion of the mold, and the gas in the cavity during injection molding is supplied to the bypass and the valve body opening portion. When the injection melt fills the cavity and reaches the end of the gas release groove, the valve body is pushed up by the action of this large mass of melt and bypassed by this valve body. Is to close the end. Then, acetylene gas A, which is a mixed gas, and air B
The needle valve 37 for acetylene and the needle valve 38 for air can be electrically operated, for example, so that the molar ratio becomes 1: 1. And a mixed gas is produced while sending both gases into the conduit, and the mixed gas is filled over the cavity of the mold, the cylindrical connecting portion 21, the cylinder 22, and the injection sleeve 14 of the release agent coating device 31. Then, the mixed gas is ignited by the ignition plug 28, soot is generated and adheres to the inner surface. Further, after the soot is applied, the molten metal is supplied into the tilted injection sleeve 14 by a pouring device (not shown). When the acetylene gas A and the air B are supplied by manually operating both the needle valves 37 and 38, the acetylene gas A and the air B can be supplied while visually checking a float type flow meter (not shown).

A method of applying soot on the contact surface of the molten metal in the die casting machine configured as described above will be described. After the mold release, the block 11 is lowered to remove the injection sleeve 14 from the bolster 3, and then the tilting device 34 is operated while the block 11 is held at the lowermost end so that the release agent applying device 31 can be easily set. Incline at an appropriate angle. Next, in order to mount the release agent applying device 31, pressure oil is supplied from a pressure oil supply port 27d through a conduit (not shown) to the second hydraulic cylinder 27, and one end of the cylindrical connection portion 21 is inserted into a hole of the bolster 3. In order to facilitate engagement and connection to the fixed mold 2, it is moved upward as much as possible,
When the cylindrical connecting portion 21 comes near the contact surface between the bolster 3 and the fixed platen 1, the pressure oil supply port is passed through a conduit (not shown) to the first hydraulic cylinder 26 while holding the pressure oil in the second hydraulic cylinder 27.
The cylinder 22 which supplies pressure oil from 26c and forms a T-shape
And the cylindrical connecting portion 21 is moved and connected to the fixed mold 2. Next, the tilting device 34 is operated to the position of the stopper 18 to position the injection device 32 in the upright position, and pressurized oil is supplied from a pressure oil supply port (not shown) to the upper portion of the cylinder 11a, and the block 11 moves to move the cylindrical connection portion. Complete the connection with 21a. Furthermore, in the mixed gas supply device 40, the acetylene gas A and the air B are
For example, the acetylene gas needle valve 3
By operating the 7 and the air needle valve 38, a predetermined amount of the mixed gas is filled in each space of the two mold cavities, the cylindrical connecting portion 21, the top region of the cylinder 22, and the injection sleeve 14. In this state, when the spark plug 28 is electrically sparked to ignite the mixed gas, an appropriate speed is given to the flame depending on the mixture ratio. Soot is generated by the combustion of the mixed gas, and the soot adheres to the surfaces of the molds facing the cavities as the contact surfaces of the molten metal, the inner surface of the injection sleeve 14, and the end surface of the plunger tip 9a. After the application of the soot, the block 11 is detached from the cylindrical connecting portion 21a by removing the pressure oil from the upper part of the cylinder 11a of the injection device 32. Thereafter, the release operation of the release agent applying device 31 is achieved by the reverse operation when the release agent applying device 31 is mounted. At this time, the injection device 32 remains tilted to the tilting device 34, and the molten metal is supplied into the injection sleeve 14 in this state. And
After raising the injection cylinder 6 and the like by the tilting cylinder 16, the block 11 is raised by the detachable cylinder 13,
The injection sleeve 14 is joined to the fixed mold 2. When the piston rod 8 of the injection cylinder 6 is raised by hydraulic pressure,
As the plunger tip 9a rises in the injection sleeve 14, the molten metal is injected into the cavity through the gate 15. After the injection, wait for the molten metal to solidify and open the mold to take out the product.

In such an injection work, soot is applied in place of a water-soluble release agent, so that it has a releasing effect as well as adheres well even when the temperature of the applied surface is as high as about 400 ° C. Since the conductivity is extremely small, about 1/100 of that of the release agent, the heat retention is good and the generation of gas is small.

In the above embodiment, soot was directly adhered to the contact surface of the molten metal such as the injection sleeve, the end surface of the plunger, and the mold cavity. This is because a lubricant or a release agent was first applied to the contact surface of the molten metal. After the application, soot may be applied to the upper surface.

Further, in the present embodiment, the injection sleeve and the plunger tip of the rigid die casting machine are illustrated as the melt contact surface for applying soot. However, a horizontal die casting machine, a squeeze casting machine, a molten metal forging machine, or the like may be used. The melt contact surface may be any surface such as a mold cavity as long as the surface contacts the molten metal.

Further, in FIG. 1, a cylinder 22 having a shape shown in FIG.
Soot may be adhered to the contact surface of the molten metal by using.

Further, the molar ratio of the mixed gas is set to 1: 1 for acetylene A: air B, but is not limited to this. When the ratio of acetylene A is increased, soot generation increases, and conversely, acetylene Decreasing the proportion of A reduces the occurrence of soot, but such a slight shift in the mixing ratio does not significantly affect soot coating.

[Effects of the Invention] As is clear from the above description, according to the present invention,
As a method of applying soot to the molten metal contact surface, a method of supplying a mixed gas from a mixed gas supply device to adhere soot due to incomplete combustion to the molten metal contact surface such as a mold cavity, an injection sleeve, and an end surface of a plunger tip is adopted. As a result, compared to the conventional release agent, soot adheres evenly to the contact surface of the molten metal and has the effect of generating less gas, and also the release agent does not scatter around the mold. The working environment in the factory is greatly improved. In addition, after clamping both molds, soot adheres only to the contact surface of the molten metal due to incomplete combustion of the mixed gas. Therefore, mold clamping is performed while the coating agent is adhered to the mold mating surfaces of both molds as in the related art. This eliminates burr blows and other problems caused by mold failure due to soot accumulation.

[Brief description of the drawings]

FIGS. 1 and 2 are views for explaining a method of applying soot to a contact surface of a molten metal according to the present invention, and FIG. FIG. 2 is a schematic longitudinal sectional view showing a schematic configuration of a die casting machine, and FIG. 2 is a schematic longitudinal sectional view showing another embodiment in which a release agent application device is implemented. 1 ... fixed board, 2 ... fixed mold, 5 ... movable mold, 6 ... injection cylinder, 8 ... piston rod, 9 ... plunger, 11 ... block, 12 ... ram, 18 ... Stopper, 21 ... Cylindrical contact part, 22 ... Cylinder, 23 ... Piston, 24 ... Spring, 26 ... First hydraulic cylinder, 27 ... Second hydraulic cylinder, 28 ... Spark plug, 31 ... Release agent coating device, 33 injection device main body, 34 tilting device, 35 degassing valve, 46 electromagnetic switching valve, 37 needle valve for acetylene gas, 38 needle valve for air, 40: mixed gas supply device, A: acetylene gas, B: air.

Claims (2)

(57) [Claims] 1. A mold release agent coating device having an ignition device is brought into contact with a member having a molten metal contact surface in a sealed state, and in this state, a gas and air is supplied from a mixed gas supply device to a space having a molten metal contact surface. And contacting the soot with the molten metal by incompletely burning the mixed gas with the igniter and causing the soot to adhere to the molten metal contact surface. Release agent application method to the surface. 2. A release agent coating device for burning a mixed gas supplied from a mixed gas supply device into a space having a molten metal contact surface to generate soot and applying the soot to the molten metal contact surface, On one side of the cylinder, a cylindrical connection portion having a connection port provided so as to be connectable to an inlet portion of the space having the melt application device is provided, and the other end is formed into a shape having a bottom portion. A piston is provided movably in the axial direction, and a spark plug for burning the mixed gas is disposed between the forward end position of the piston and the connection port. The piston is provided on a part of the outer peripheral surface of the cylinder between the limit position and the reverse limit position, and a piston movable between the front and the rear of the discharge port position is movably provided in the cylinder. A release means for returning the piston after ignition during the ignition, and a piston on the other end of the return means on the top side, wherein the piston is fixed to the molten metal contact surface. .