JPH09295118A - Plunger tip of die casting machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plunger tip of a die casting machine which can prevent entertainment of gas by restraining the disturbance of molten metal in an injection sleeve accompanied with the advancing movement of the plunger tip. SOLUTION: The front end surface of the plunger tip 10 constitutes a molten metal pushing surface 11 and the molten metal M in the injection sleeve 20 having horizontal axial line, is filled into a die cavity by advancing movement of the plunger tip 10. The molten metal pushing surface 11 is inclined to the vertical surface orthogonal to the axial line of the injection sleeve 20, and the lower end surface 11a of the pushing surface 11 is positioned to the front part from the upper end part 11b. The molten metal M runs onto the inclined pushing surface 11 and thus, the extreme waving surface is not caused.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plunger tip of a die casting machine, and more particularly to a plunger tip of a die casting machine for suppressing the disturbance of the molten metal in the injection sleeve due to the forward movement of the plunger tip.
The present invention further relates to a plunger chip of a die casting machine capable of preventing the solidified material of the molten metal generated in the injection sleeve from mixing with the molten metal.

[0002]

2. Description of the Related Art A plunger tip is reciprocally slidably provided in an injection sleeve whose axis extends horizontally. With the forward movement of the plunger tip, the melt extruded surface at the tip of the plunger tip causes the melt in the injection sleeve to move. Fill the mold cavity. Here, the conventional plunger tip is
As shown in FIG. 5, the molten metal extrusion surface 111 is a vertical plane V orthogonal to the axis of the injection sleeve 20.

[0003]

Since the molten metal extruding surface 111 of the conventional plunger tip 110 is the vertical plane V orthogonal to the axis of the injection sleeve 20, the molten metal extruding surface 111 is moved by the forward movement of the plunger tip 110. May cause the molten metal M to swell and scatter the molten metal M as shown in FIG. 5 (A) to disturb the molten metal M, and the gas G may be caught in the molten metal M as shown in FIG. 5 (B). is there. The molten metal M supplied into the injection sleeve 20 is
There is a tendency for the lower part of the inner peripheral surface of 0 to contact and solidify, and the solidified layer S is formed at the location. When the plunger tip 110 is moved forward in this state, the plunger tip 1
The solidified layer S is scraped off by the lower part of the molten metal extrusion surface 111 of 10 to form a solidified piece P, which is peeled off. Then, the above-mentioned molten metal M
The separated solidified pieces P are mixed into the molten metal M due to
It causes deterioration of casting quality.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a plunger chip for a die casting machine in which disturbance of the molten metal in the injection sleeve due to the forward movement of the plunger chip is suppressed and gas entrainment in the injection sleeve does not occur. To do. Another object of the present invention is to provide a plunger tip of a die casting machine capable of preventing the solidified material generated in the lower portion of the injection sleeve from being mixed into the molten metal after peeling.

[0005]

In order to achieve the above object, the present invention is directed to a forward movement in an injection sleeve whose axis extends horizontally to extrude the molten metal in the injection sleeve by a molten metal extruding surface at the tip. In a plunger chip of a die casting machine for filling a mold cavity, the molten metal extrusion surface 11,
Plunger chip 10 of die casting machine, in which 11 'and 11 "are inclined with respect to a vertical plane V orthogonal to the axis,
We offer 10 ', 10 ".

In the present invention, further, the lower end 11a of the inclined molten metal extruding surface 11 is located in front of the upper end 11b,
Provided is a plunger tip 10 of a die casting machine which extends linearly between a lower end 11a and an upper end 11b.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A plunger chip of a die casting machine according to a first embodiment of the present invention will be described with reference to FIGS. The injection sleeve 20 has its axis extending horizontally and is connected to a mold (not shown). A pouring port (not shown) is formed in the injection sleeve 20, and the molten metal M is supplied from the pouring port into the injection sleeve 20. A plunger tip 10 is provided in the injection sleeve 20 so as to be reciprocally movable. The rear end side of the plunger tip 10 is connected to the cylinder rod 13, and the cylinder rod 13 is connected to an injection cylinder (not shown). The tip side of the plunger tip 10 forms a molten metal extruding surface 11, and when the plunger tip 10 moves forward, the molten metal M in the injection sleeve 20 is filled by the molten metal extruding surface 11 into a mold cavity (not shown). The molten metal extruding surface 11 is inclined with respect to a vertical plane V orthogonal to the axis of the injection sleeve 20, and in this embodiment, the lower end 11a of the molten metal extruding surface 11 is located in front of the upper end 11b. A straight line extends between the portion 11a and the upper end portion 11b.

In the above construction, when the molten metal M is supplied into the injection sleeve 20 from a pouring port (not shown), the molten metal M contacts the lower inner peripheral surface of the injection sleeve and is cooled as shown in FIG. The contact portion becomes the solidified layer S. When the plunger tip 10 is slid in the forward direction by an injection cylinder (not shown) after pouring, the molten metal M is extruded from the molten metal extruding surface 11 and filled in the die cavity (not shown). At this time, as shown in FIG. 2, since the lower end portion 11a of the plunger tip sunk into the lower portion of the molten metal, the molten metal smoothly rises up along the slope of the molten metal extruding surface 11 and does not cause any extreme waviness. Gas is not caught in the molten metal M.

With the forward movement of the plunger tip 10, the solidified layer S is separated from the inner peripheral surface of the injection sleeve 20 by the lower end 11a of the molten metal extruding surface 11, and the separated solidified layer S is an inclined extruded surface. Start climbing along 11. The tip of the solidified layer S that has been peeled off is the injection sleeve 20.
The solidified layer S is continuous without being broken until it comes into contact with the upper end of the inner periphery of the, and as shown in FIG. In other words, the solidified layer S that has been peeled off does not become finer, so there is no risk of mixing into the molten metal M.

FIG. 4 shows another embodiment of the plunger tip of the die casting machine according to the present invention. FIG. 4 (A) shows a cone in which the center of the molten metal extruding surface 11 'is located ahead of other portions. 4B has a conical concave shape in which the center of the molten metal extruding surface 11 ″ is located rearward of the other portions. In either case, the first embodiment is different from the first embodiment. In contrast, since the molten metal extruding surfaces 11 ', 11 "are not surfaces extending in a straight line, the separated solidified layer S cannot be along the extruding surface which is a slope, but the molten metal extruding surfaces 11', 11" Is inclined with respect to the vertical plane orthogonal to the axis of the injection sleeve 20, so that the disorder of the molten metal M can be suppressed even by the forward movement of the plunger tips 10 ′, 10 ″.

The plunger chip of the die casting machine according to the present invention is not limited to the embodiment described above, and various modifications can be made. For example, in the first embodiment,
It is also within the scope of the present invention to make the slope of the molten metal extrusion surface gentle so that the length of the slope is as long as possible and the length of the separated solidified layer S is as large as possible.

[0012]

According to the plunger tip of the die casting machine of the first aspect described above, since the molten metal extruding surface is inclined with respect to the vertical plane orthogonal to the axis of the injection sleeve, even when the plunger tip moves forward. Since the molten metal does not generate an extreme wave front and the molten metal does not easily splash, the gas in the injection sleeve can be prevented from being caught in the molten metal, and the behavior of the molten metal is stable. Even when the object is separated from the injection sleeve, the solidified material does not rise up into the molten metal.

According to the plunger tip of the die casting machine of the second aspect, the layer solidified in the inner lower portion of the injection sleeve is separated from the lower portion of the injection sleeve by the lower portion of the molten metal extrusion surface of the plunger tip as the plunger tip advances. Since the lower end of the molten metal extruding surface is located in front of the upper end and extends linearly between the lower end and the upper end,
The separated solidified layer is lifted along the molten metal extruding surface and is not refined. Therefore, it is possible to prevent the solidified pieces from being mixed into the molten metal and prevent the quality of the cast product from being deteriorated.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an initial stage of an injection operation of a plunger chip of a die casting machine according to a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing an intermediate stage of the injection operation of the plunger chip of the die casting machine according to the first embodiment of the present invention.

FIG. 3 is a schematic cross-sectional view showing a state in which the plunger tip of the die casting machine according to the first embodiment of the present invention is further advanced.

FIG. 4 is a schematic perspective view showing a plunger chip of a die casting machine according to another embodiment of the present invention,
(A) shows an example in which the center of the molten metal extruding surface projects, and (B) shows an example in which the center recedes.

FIG. 5 is a schematic cross-sectional view showing a plunger tip of a conventional die casting machine, (A) shows a state in which the molten metal is undulated as the plunger tip moves forward, and (B) shows a solidified piece or the like in the molten metal. A state in which gas is mixed is shown.

[Explanation of symbols]

 10, 10 ', 10 "Plunger tip 11, 11', 11" Molten metal extrusion surface 20 Injection sleeve

Claims (2)

[Claims] 1. A plunger chip of a die casting machine in which a molten metal in the injection sleeve is extruded by a molten metal extruding surface at a tip end to be filled in a mold cavity by advancing in an injection sleeve whose axis extends horizontally. A plunger chip for a die casting machine, wherein an extrusion surface is inclined with respect to a vertical plane orthogonal to the axis. 2. The plunger of a die casting machine according to claim 1, wherein the molten metal extruding surface has a lower end portion located in front of an upper end portion and extends linearly between the lower end portion and the upper end portion. Chips.