JP6847722B2 - Hot chamber casting equipment - Google Patents

Description

The present invention relates to a hot chamber casting apparatus for manufacturing a die-cast product such as aluminum.

Casting methods for die-cast products manufactured from aluminum alloys include a hot chamber method in which injection is performed in a relatively high-temperature molten metal (molten metal material) and a cold chamber in which injection is performed while the molten metal is supplied into the sleeve. It is roughly divided into methods. Of these, the hot chamber method has merits such as being able to cast pure aluminum having a relatively high melting point and having a wide selection range of cast metal materials.

As a conventional hot chamber type aluminum die casting device, for example, a vertical injection chamber is generally used as shown in FIG. 8 (see, for example, Patent Documents 1 and 2). This type of vertical chamber has a structure in which the plunger 92 slides up and down in the main cylinder 91 to pressurize and supply the metal material stored in the pod 93 to the mold 95 via the branch cylinder 94. ..

Japanese Unexamined Patent Publication No. 2010-058131 Japanese Unexamined Patent Publication No. 2011-11566

However, the conventional vertical chamber has a structure in which the plunger 92 is pressed vertically to inject a metal material, and a portion where a gooseneck, which is called a gooseneck, bends sharply between the main cylinder and the branch cylinder ( For example, since the runner portion 96) shown in FIG. 8 is present, a relatively high injection pressure is required. Therefore, due to the structure, the mechanical load on the chamber is large, and there are problems in durability and device life. In addition, there is a possibility that oxides floating on the surface of the molten aluminum adhere to the sliding parts of the main cylinder and the plunger, which causes impurities to be mixed into the injection metal material and damage to the chamber device. Further, for example, a metal material such as pure aluminum has a high freezing point temperature and has a property of rapidly solidifying. Therefore, in the conventional vertical chamber, it is difficult to handle the metal remaining in the runner after casting, such as solidification.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide a casting apparatus capable of dealing with a metal material having a high freezing point such as pure aluminum.

In order to solve the above-mentioned problems, the present invention is a hot chamber casting apparatus for injecting molten metal into a mold to manufacture a cast product, in which a pod for heating and holding the molten metal and one end thereof are connected to the mold. A nozzle tube fixed to the pod and formed with a channel portion for injecting molten metal into the mold, a chamber cylinder connected to the other end of the nozzle tube and fixed to the pod, and the inside of the chamber cylinder. A piston accommodated so as to reciprocate in the molten metal and an injection drive device for reciprocating the piston in the chamber cylinder are provided, and the entire chamber cylinder is fixed to the pod while being immersed in the molten metal. The tip of the rod of the hydraulic cylinder provided in the injection drive device is provided with a hemispherical core portion that abuts on the base end portion of the piston .

In the hot chamber casting apparatus, it is preferable that the chamber cylinder is fixed to the pod so that the injection direction of the molten metal is horizontal. Further, the chamber cylinder may be inclined and fixed to the pod so that the injection direction of the molten metal is obliquely upward.

Further, in the hot chamber casting apparatus, the nozzle pipe is inclined upward on the mold side and fixed to the pod, and a bent portion is formed in an injection runner portion where the nozzle pipe and the chamber cylinder are connected. Is preferable.

Further, in the hot chamber casting apparatus, it is preferable that the movement line in the direction in which the piston reciprocates in the chamber cylinder and the action line of the pressing force applied to the piston coincide with each other.

According to the hot chamber casting apparatus of the present invention, high-speed casting is possible, and it is possible to deal with metal materials having a high freezing point such as pure aluminum.

It is a side view of the hot chamber casting apparatus by one Embodiment of this invention. It is a figure which illustrates the connection structure of one end part of the nozzle tube and a mold in the hot chamber casting apparatus of FIG. It is a figure which illustrates the connection structure of the other end of the nozzle tube and a chamber cylinder in the hot chamber casting apparatus of FIG. It is a figure which illustrates the connection structure of the rod and the piston of the hydraulic cylinder in the hot chamber casting apparatus of FIG. It is a figure for demonstrating the operation of the hot chamber casting apparatus of FIG. It is a figure for further explaining the operation of the hot chamber casting apparatus of FIG. It is a figure for further explaining the operation of the hot chamber casting apparatus of FIG. It is a figure for demonstrating the structure of the vertical chamber by a prior art.

Hereinafter, preferred embodiments of the hot chamber casting apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a side view showing a configuration of a hot chamber casting apparatus 10 according to an embodiment of the present invention.

The hot chamber casting apparatus 10 pressurizes and injects a molten metal material (hereinafter referred to as “molten metal”) W such as pure aluminum heated and held in the pod 60 into the cavity 73, which is a space in the mold, at high speed. , A device for manufacturing a cast product having a desired shape. The pod 60 is a tank capable of heating and holding the molten metal W at a temperature of, for example, 700 ° C. or higher. For example, it is preferable to manufacture the pod 60 using a heat-resistant material having excellent erosion resistance such as Tokenite (registered trademark). Further, the pod 60 is appropriately replenished with a solid metal material (ingod), and the molten metal level is kept constant.

Examples of the metal material of the cast product produced by the hot chamber casting apparatus 10 include aluminum, aluminum alloy (for example, Al-Si-based, Al-Si-Cu-based), copper alloy, magnesium alloy, zinc alloy and the like. In particular, in the hot chamber casting apparatus 10 according to the present embodiment, since the entire chamber is immersed in the molten metal, it is possible to prevent impurities from being mixed into the metal material. Further, it is suitable for casting precision parts made of pure aluminum having high thermal conductivity, for example, in that injection molding at high temperature and high speed is possible.

The hot chamber casting apparatus 10 according to the present embodiment includes the above-mentioned pod 60 that heats and holds the molten metal, a nozzle tube 20 configured to inject the molten metal W into a mold (fixed mold 71, movable mold 72), and the inside. A cylindrical chamber cylinder 30 having a chamber 31 and a piston 50 housed so as to reciprocate within the chamber cylinder 30 are provided. In the present embodiment, the mold is formed by abutting the fixed mold 71 and the movable mold 72 having a cavity 73 recessed in the desired cast shape.

The nozzle tube 20 is made of heat-resistant ceramic and has a substantially columnar shape extending straight. The nozzle tube 20 is formed with a runner portion 21 that penetrates the main body in the longitudinal direction. As shown in FIG. 2, one end 23 of the nozzle tube 20 is connected to, for example, a fixed mold 71 constituting the mold. One end 23 of the nozzle tube 20 has a spherical shape and is in pressure contact with the concave surface 71a inside the fixed mold 71.

Further, the other end 24 of the nozzle tube 20 is connected to a cap plate 36 that closes the injection side of the chamber cylinder 30. As shown in FIG. 3, the other end 24 of the nozzle tube 20 has a spherical shape and is in pressure contact with the concave surface 36a of the cap plate 36. A hot hole portion 36b is formed in the cap plate 36. That is, the molten metal W discharged from the chamber cylinder 30 by the piston 50 flows through the hot water hole portion 36b of the cap plate 36 and the hot water passage portion 21 of the nozzle pipe 20, and enters the cavity 73 via the injection passage 71b of the fixed mold 71. Be ejected.

The nozzle tube 20 penetrates the pod 60 in a posture in which the mold (71, 72) side is inclined upward and is fixed to the pod 60. Then, as shown in FIG. 3, a bent portion is formed in the injection runner portion where the other end 24 of the nozzle pipe 20 and the cap plate 36 of the chamber cylinder 30 are connected.

The portion where the nozzle tube 20 penetrates the pod 60 is in the molten metal W. Therefore, in order to prevent the molten metal W from leaking to the outside from the penetrating portion of the pod 60, the penetrating portion of the nozzle tube 20 is sealed with a heat-resistant seal 62 having excellent erosion resistance such as glass fiber or ceramic. It is preferable to stop.

Further, it is preferable to provide a heater 27 for keeping the nozzle tube 20 at a high temperature by winding the surface portion of the nozzle tube 20 between the pod 60 and the molds (71, 72). The heater 27 can maintain the molten state of the metal material and improve the drainage of the metal material that tends to remain in the channel 21 after casting. Further, it is preferable that the heater 27 is in close contact with the pod 60 and heats at least a part of the fixed mold 71.

Both the chamber cylinder 30 and the piston 50 are made of heat-resistant ceramic. The chamber cylinder 30 has a hollow cylindrical main body, and an introduction hole portion 32 is formed through the main body. The entire chamber cylinder 30 is fixed to the pod 60 in a state of being immersed in the molten metal W. As a result, metal oxides and the like floating on the surface of the molten metal W during the casting operation are not introduced into the chamber 31, and impurities can be prevented from being mixed into the metal material. Therefore, the purity of the cast product can be ensured.

The piston 50 is inserted into the chamber cylinder 30 fixed to the pod 60 from the outside, and is provided so as to be reciprocally movable so as to make the volume of the chamber 31 variable.

The injection drive device 40 is adapted to reciprocate the piston 50 within the chamber cylinder 30. The injection drive device 40 includes a hydraulic cylinder 41. The tip of the rod 42 of the hydraulic cylinder 41 is connected to the base end of the piston 50 via a coupler 55. For example, as shown in FIG. 4, it is preferable that the moving axis Ax in the direction in which the piston 50 reciprocates in the chamber cylinder 30 and the action line of the pressing force Fi applied to the piston 50 coincide with each other. As a result, the pressing force generated by the hydraulic cylinder 41 can be efficiently transmitted to the piston 50.

Further, as shown in FIG. 4, it is preferable that the tip of the rod 42 of the hydraulic cylinder 41 is provided with a hemispherical core portion 42a that abuts on the base end portion of the piston 50. Since the pressing force Fi transmitted through the rod 42 acts on the piston 50 at the apex of the core portion 42a, it is possible to prevent the generation of unwanted bending moments and stresses at the connecting portion between the rod 42 and the piston 50, and it is durable. It is possible to improve the property and extend the life. The coupler 55 may be a universal joint for the purpose of suppressing unnecessary bending moments and stresses.

In the embodiment of FIG. 1, the chamber cylinder 30 is fixed to the pod 60 in a horizontal posture so that the injection direction of the molten metal W is horizontal. Further, the chamber cylinder 30 may be fixed to the pod 60 in a slightly inclined posture so that the injection direction of the molten metal W is obliquely upward. As described above, by making the chamber cylinder 30 a horizontal straight type, the pressure loss of the injection runner portion from the chamber to the mold can be reduced as much as possible, thereby enabling high-speed casting.

The casting operation by the hot chamber casting apparatus 10 having such a configuration is as follows. First, in order to introduce the molten metal W into the chamber 31, as shown in FIG. 5, the rod 42 of the hydraulic cylinder 41 is degenerated and the piston 50 is moved outward of the chamber cylinder 30. At this time, the volume of the chamber 31 is increased and the pressure is reduced, so that the molten metal W is introduced into the chamber 31 through the introduction hole 32 of the chamber cylinder 30.

Next, as shown in FIG. 6, the rod 42 of the hydraulic cylinder 41 is extended to move the piston 50 inward of the chamber cylinder 30. As a result, the inside of the chamber 31 is pressurized, and the molten metal W is injected into the cavity 73 in the mold through the runner portion 21 of the nozzle pipe 20. Then, after the molten metal in the cavity 73 is cooled and solidified, as shown in FIG. 7, the hydraulic cylinder 75 is degenerated and the movable mold 72 is separated from the fixed mold 71 to obtain a cast product M having a predetermined shape. Be done.

According to the hot chamber casting apparatus 10 of the present embodiment, the durability and the life can be extended by simplifying the main chamber structure. In particular, by making the chamber cylinder 30 a horizontal straight type, the pressure loss of the injection runner portion from the chamber to the mold can be reduced as much as possible, thereby enabling high-speed casting.

Further, since the injection pressure loss is suppressed and high-speed casting is possible as compared with the conventional case, it is possible to deal with a metal material having a high freezing point such as pure aluminum.

10 Hot chamber casting equipment 20 Nozzle pipe 21 Channel 27 Heater 30 Chamber cylinder 31 Cylinder 32 Introduction hole 36 Cap plate 40 Injection drive 41 Hydraulic cylinder 42 Rod 50 Piston 55 Coupler 57 Heater 60 Pod (melting tank)
71 Fixed mold 72 Movable mold 73 Cavity W Molten metal M Cast product

Claims (4)

A hot chamber casting device for injecting molten metal into a mold to manufacture a cast product.
A pod that heats and holds the molten metal,
A nozzle tube having one end connected to the mold and fixed to the pod to form a runner for ejecting molten metal into the mold.
A chamber cylinder connected to the other end of the nozzle tube and fixed to the pod,
A piston housed to reciprocate within the chamber cylinder ,
It is provided with an injection drive device for reciprocating the piston in the chamber cylinder.
The entire chamber cylinder is fixed to the pod while being immersed in the molten metal .
A hot chamber casting device in which a hemispherical core portion abutting on a base end portion of the piston is provided at the tip of a rod of a hydraulic cylinder provided in the injection drive device. The hot chamber casting apparatus according to claim 1, wherein the chamber cylinder is fixed to the pod so that the injection direction of the molten metal is horizontal. The hot chamber casting apparatus according to claim 1, wherein the chamber cylinder is inclined and fixed to the pod so that the injection direction of the molten metal is obliquely upward. Any of claims 1 to 3, wherein the nozzle pipe is fixed to the pod with the mold side inclined upward, and a bent portion is formed in an injection runner portion connecting the nozzle pipe and the chamber cylinder. The hot chamber casting apparatus according to item 1.

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