JPH078426B2 - Device for applying powdery thermal insulation agent to the inner surface of the injection sleeve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention is intended to cast a molten metal (molten metal) which has been supplied in a single injection sleeve into a cavity of a mold by injection filling. The present invention relates to an applicator for applying the powdery heat insulating agent to the inner surface of the injection sleeve in the casting device.

<Prior art> The molten metal (molten metal) supplied in the injection sleeve has a rapid temperature drop, and if it is not injected and filled into the cavity of the mold promptly after the water is supplied, it will partially solidify, resulting in defective filling and casting surface defects. Occurs. However, when injected at high speed, gas (air, etc.) in the injection sleeve is entrained, and many porosity and pinholes are generated.

Therefore, when casting a high-quality product with no casting surface defects or porosity with high productivity, the molten metal supplied in the injection sleeve is solidified for a certain time (until injection filling into the mold cavity). It is an important condition to hold so as not to.

Therefore, as a method of preventing solidification of the molten metal in the injection sleeve, the following methods have been conventionally considered.

A method of molding the injection sleeve with ceramic with high heat retention.

How to make a hot chamber.

A method that minimizes contact between the injection sleeve and the molten metal, including vertical injection.

A method of externally heating the injection sleeve.

However, the above method has a problem in impact resistance and has not been put into practical use at this stage.Also, the above method can be applied to a molten metal with a low melting point such as zinc, but it can be applied to a molten metal with a high melting point such as aluminum. Has not been put to practical use. In addition, the above method has practically no effect, and the above method has a problem that maintenance is difficult and productivity is deteriorated.

Therefore, the inventor of the present application proposes a method of applying a powdery heat insulating agent to the inner surface of the injection sleeve to keep the molten metal supplied in the injection sleeve warm so as not to solidify. When applying the powdery heat insulating agent to the inner surface of the injection sleeve, a spray method using a gas such as an error or a method of putting the powdery heat insulating agent in a cloth bag and rubbing or tapping it like a rosin bag, or An electrostatic coating method using static electricity can be considered. However, in the above-mentioned spray method or rosin back method, it is very difficult to uniformly apply the powdery heat insulating agent to the entire inner surface of the injection sleeve, and it is inefficient and the workability is poor.
Even in the case of the electrostatic coating method, in the method of blowing the pre-charged powdery heat insulating agent into the injection sleeve, only the vicinity of the blow-in port into which the powdery heat insulating agent is blown becomes dense and becomes sparse as it goes deeper, and It is very difficult to apply it evenly on the inner surface, and even if you use the existing electrostatic coating gun, the coating gun is larger than the inner diameter of the injection sleeve, so you can only apply it from the outside of the injection sleeve. There is a problem that it is difficult to uniformly apply the powdery heat insulating agent to the inner surface.

<Problems to be Solved by the Invention> The present invention has been made in view of such problems.
It is an object of the present invention to provide an apparatus for applying a powdery heat insulating agent, which can easily, reliably and evenly apply the powdery heat insulating agent to the inner surface of the injection sleeve.

<Means for Solving the Problems> An apparatus for applying a powdery heat insulating agent to the inner surface of an injection sleeve of the present invention which achieves such an object is a high voltage generator, a positive electrode and a negative electrode connected to the high voltage generator. The electrode, an electrode transport mechanism for inserting and transporting one of the electrodes into and out of the injection sleeve so as to be freely transported, and a heat insulating agent supply mechanism for blowing a powdery heat insulating agent into the injection sleeve, and the high voltage The other electrode of the generator is electrically connected to the injection sleeve side, and an electrostatic electric field is generated between the inner surface of the injection sleeve and the one electrode inserted into the injection sleeve to inject powder into the injection sleeve. In a coating device in which the heat insulating agent is coated on the inner surface of the injection sleeve, the electrode transfer mechanism may be mounted on an arm installed on a fixed plate of a die casting machine so that a drive cylinder is swingably mounted. A guide plate formed in a gentle arc shape at the tip of the arm is attached toward the pouring mouth of the injection sleeve, and a support tool provided with a guide roller is attached to the rod tip of the drive cylinder. The guide plate is movably connected to the guide plate through a guide roller, and one electrode electrically connected to the high voltage generator is attached to the support member so as to be substantially along the guide plate. It is what

<Function> While inserting one electrode connected to the high voltage generator into the injection sleeve and electrically connecting the other electrode to the injection sleeve side, while blowing or filling the injection sleeve with the powdery heat insulating agent, When a high voltage is applied between the inner surface of the injection sleeve and the one electrode by a high voltage generator, an electrostatic electric field is generated between the inner surface of the injection sleeve and the one electrode, and the powder inside the injection sleeve is generated. The heat insulating agent is charged, and the charged powdery heat insulating agent is instantaneously adhered and applied to the inner surface of the injection sleeve.

<Example> Hereinafter, an example of the present invention is described based on a drawing.

In the figure, A is a well-known die casting machine, which has a fixed plate 1, an injection sleeve 2 and a fixed mold 3 attached to the fixed plate 1, a movable mold 5 attached to a movable plate 4, and the like as in the conventional case. After the fixed mold 3 and the movable mold 5 are closed, the molten metal (molten metal) supplied from the pouring port 6 of the injection sleeve 2 is injected and filled into the cavity 8 of the mold with the plunger tip 7. The desired product can then be cast.

Then, either the plus or minus electrode 9a connected to the high voltage generator 9 is inserted into the injection sleeve 2 so as to be freely inserted and removed, and the other electrode 9b of the high voltage generator 9 is inserted into the injection sleeve 2. Is electrically connected to the side of the injection sleeve 2, and a high-voltage is applied between the inner surface of the injection sleeve 2 and one of the electrodes 9a inserted in the injection sleeve 2 while blowing or filling the injection sleeve 2 with a powdery heat insulating agent. The powdery heat insulating agent is applied to the inner surface of the injection sleeve 2.

That is, in the coating apparatus according to the present invention, the high voltage generator 9, the plus electrode and the minus electrode connected to the high voltage generator 9, and either the plus or minus electrode 9a are provided inside the injection sleeve 2. It is composed of an electrode transport mechanism 10 for inserting and transporting in and out freely, and a heat insulating agent supply mechanism 11 for blowing a powdery heat insulating agent into the injection sleeve 2.

The high voltage generator 9 is a well-known one that can generate a high voltage of about 10 to 100 KV between the positive electrode and the negative electrode connected to the high voltage generation control unit. It is installed on the fixed board 1 of A, and either the positive electrode or the negative electrode 9a of the positive electrode or the negative electrode is preferably prevented from electrically contacting the inside of the injection sleeve 2 with the injection sleeve 2 side by the electrode transfer mechanism 10. When inserted into the injection sleeve 2, the injection sleeve 2 is inserted and removed so as to be substantially aligned with the axis of the injection sleeve 2, and the other electrode is inserted.
9b is electrically connected to the injection sleeve 2 side. Whether the one electrode 9a or the other electrode 9b is the positive side or the negative side is determined by the electrical property (polarity) of the powdery heat insulating agent applied to the inner surface of the injection sleeve 2. When the other electrode 9b is electrically connected to the injection sleeve 2 side, the other electrode 9b may be directly connected to the injection sleeve 2, but the fixed plate 1 supporting the injection sleeve 2 is electrically connected. You may make it connect physically.

The electrode transfer mechanism 10 is for transferring one electrode 9a connected to the high voltage generator 9 into and out of the injection sleeve 2 freely, and is a base plate fixed on the fixed plate 1 of the die casting machine A. A rail 12a is laid on the rail 12, and an arm 13 is attached to the rail 12a by a cylinder 14 so as to be horizontally movable. A driving cylinder 15 is pivotally attached to the arm 13.
The guide plate 17 is attached to the tip end portion 13a of the arm 13 in a gentle arc shape toward the pouring port 6 of the injection sleeve 2, and is further attached to the tip end of the rod 15a of the drive cylinder 15. A support tool 19 provided with a guide roller 18 is attached to the support tool 19, and the support tool 19 is movably connected to the guide plate 17 via the guide roller 18,
One electrode 9a connected to the high voltage generator 9 is attached to 19 so as to be substantially along the guide plate 17, and one electrode 9a is put into and taken out from the pouring port 6 of the injection sleeve 2 into the injection sleeve 2. It is composed. The one electrode 9a connected to the high voltage generator 9 is formed to have substantially the same length as the injection sleeve 2 and is formed of a conductive material having a certain degree of rigidity so as not to bend in the middle.
A high voltage generator 9 installed on the fixed plate 1 of 1 is electrically connected with a cord 20. The arm 13 is configured to be movable in the horizontal direction because the guide plate 17 attached to the arm 13 and one electrode when pouring the molten metal into the injection sleeve 2
This is because 9a interferes, and the arm 13 may be configured to be vertically movable so as not to interfere with the pouring.
Further, the plane shape of the pouring port 6 of the injection sleeve 2 is formed in an elliptical shape that is long in the axial direction so that the one electrode 9a connected to the high voltage generator 9 can be easily put in and taken out from the pouring port 6 of the injection sleeve 2. Alternatively, it is preferable to form the notch 6a that is long in the axial direction as in the illustrated example.

Then, the arm 13 is held by the cylinder 14 and the injection sleeve 2
When the rod 15a of the drive cylinder 15 is extended in that state by horizontally moving it to a position directly above (state of FIG. 1),
The support tool 19 attached to the tip of the rod 15a is guided by the guide plate 17, and the support tool 19 moves toward the tip of the guide plate 17 as shown in FIG. One electrode 9a is inserted into the injection sleeve 2 from the pouring port 6 of the injection sleeve 2. And the drive cylinder 15
If the rod 15a of the above is shortened to the original state, one electrode 9a connected to the high voltage generator 9 is traced in the reverse process to the above.
Is pulled out of the injection sleeve 2 and returns to the state of FIG.

Further, the heat insulating agent supply mechanism 11 for blowing the powdery heat insulating agent into the inside of the injection sleeve 2 includes a heat insulating agent supply source, a pressure feeding device for pressure-feeding the powdery heat insulating agent from the supply source, and the powdery heat insulating agent. A nozzle 11a for blowing into the sleeve 2 (note that only the nozzle portion is shown as a heat insulating agent supply mechanism in the illustrated embodiment), and whether the nozzle 11a faces the blowing opening of the injection sleeve 2 Alternatively, it is inserted into the injection sleeve 2 through the blow-in port, or the injection sleeve 2
While inserting it once and pulling it out, move the nozzle 11a
The powdery heat insulating agent is blown out of the container to fill the injection sleeve 2 with the powdery heat insulating agent. As a blow-in port for blowing the powdery heat insulating agent into the injection sleeve 2, it is of course possible to form a special opening in the injection sleeve 2 and also use the pouring port 6 and the injection port 2a of the injection sleeve 2 as well. May be. or,
When a powdery heat insulating agent is blown into the injection sleeve 2 to fill it, a dephasor (diffuser) may be attached to the nozzle 11a to improve its efficiency, or two or more blowout ports may be simultaneously or separately provided or intermittently. Alternatively, the air may be blown into the air, or may be sucked from the opposite side while being blown from the air blow opening.

Further, as the powdery heat insulating agent used in the present invention, powder which is non-reactive with the molten metal, more specifically, powder having electrostatic properties such as boron and talc, or metal oxide, metal sulfide, metal nitride And the like, or a powder obtained by mixing resin powder with these powders. In particular, in order to improve the sliding property of the plunger tip 7 with respect to the inner surface of the injection sleeve 2, the powder state Therefore, it is preferable to use a powder having a self-lubricating property.

Then, one electrode 9a connected to the high voltage generator 9 is inserted into the injection sleeve 2 by the electrode transport mechanism 10, and the powdery heat insulating agent is supplied by the heat insulating agent supply mechanism (nozzle 11a) 11. A high voltage is applied between the electrode 9a on one side and the electrode 9b on the other side by the high voltage generator 9 while the gas is being blown or filled, and between the inner surface of the injection sleeve 2 and the electrode 9a. Then, an electrostatic field is generated to charge the powder heat insulating agent in the injection sleeve 2. Then, the charged powder heat insulating agent is instantaneously applied and applied to the inner surface of the injection sleeve 2, and the heat insulating layer 23 including the powder heat insulating agent 21 and the void 22 is formed on the inner surface of the injection sleeve 2 as shown in FIG. It is formed.
After that, one of the electrodes 9a is pulled out from the injection sleeve 2 by the electrode transport mechanism 10, the molten metal is supplied into the injection sleeve 1, and the plunger tip 7 is used to form the cavity 8 of the mold.
The product is cast by filling the inside with injection. Therefore, the powdery heat insulating agent is applied to the inner surface of the injection sleeve 2 in each casting cycle.

<Effect of the Invention> Since the apparatus for applying the powdery heat insulating agent to the inner surface of the injection sleeve according to the present invention is configured in this way, the powdery heat insulating agent can be easily and reliably applied to the inner surface of the injection sleeve by the electrostatic attraction. Moreover, it can be applied uniformly and evenly.

Therefore, the intended purpose can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to FIG. 4 show a first embodiment of the present invention, and FIG. 1 shows a state before inserting one electrode connected to a high voltage generator into an injection sleeve. 2 is a sectional view showing a state after one electrode is inserted into the injection sleeve,
FIG. 3 is a side view in the state of FIG. 2, and FIG. 4 is a plan view of a state in which the arm of the electrode transport mechanism is moved horizontally from the position directly above the ejection sleeve. Further, FIG. 5 is a schematic diagram illustrating a state in which a powdery heat insulating agent is applied to the inner surface of the injection sleeve. In the figure A: Die casting machine, 2: Injection sleeve 9: High voltage generator, 9a: One electrode 9b: The other electrode, 10: Electrode transport mechanism 11: Heat-insulating agent supply mechanism, 11a: Nozzle

Continuation of the front page (56) Reference JP 61-42462 (JP, A) JP 63-137539 (JP, A) JP 62-127150 (JP, A) JP 2-11259 (JP , A) Japanese Patent Publication Sho 53-9172 (JP, B2)

Claims (1)

[Claims] 1. A high voltage generator, a plus electrode and a minus electrode connected to the high voltage generator, and an electrode carrying mechanism for inserting and carrying one of the electrodes into and out of an injection sleeve. A heat insulating agent supply mechanism for blowing a powdery heat insulating agent into the injection sleeve, and the other electrode of the high voltage generator is electrically connected to the injection sleeve side. In an applicator in which an electrostatic electric field is generated between the inserted one electrode and the powdery heat insulating agent blown into the injection sleeve is applied to the inner surface of the injection sleeve, the electrode transfer mechanism is used for pouring. A supporting tool for supporting one electrode electrically connected to the high-voltage generator is attached to the rod tip of the driving cylinder that is swingably arranged at a position where it does not interfere, and the supporting tool is attached to the injection sleeve. Coating apparatus of powdery insulation material in the injection sleeve inner surface is movably interlocking with the guide plate allowed disposed toward the pouring port side of the injection sleeve, characterized in that it is constructed by a person.