JPH069726Y2 - Molten metal pressure feeding device - Google Patents

Description

[Detailed Description of the Invention] (Industrial application field) The present invention pressurizes and feeds a molten low melting point metal held in a holding furnace to a die arranged outside the machine to remove the core of the low melting point metal. The present invention relates to a molten metal pressure feeding device for casting.

(Prior art and its problems) In recent years, cores cast from a low-melting-point metal are often used for manufacturing hollow bodies having complicated shapes. For this, a plunger-type molten metal pressure feeding device is used, in which the plunger cylinder is immersed in the molten metal in the holding furnace, and the plunger piston feeds the molten metal in the plunger cylinder to the mold through a nozzle. It is generally done.

On the other hand, many low melting point metals contain bismuth, and this bismuth has the property of expanding when solidified, and when the holding furnace of the molten metal pressure feeding device is cut off due to a power failure or other abnormality As the molten metal solidifies in the holding furnace, the molten metal in the plunger cylinder also solidifies and expands. Therefore, when the plunger piston is at the rising end, an excessive force is applied to each part of the plunger cylinder to deform or damage the device.

(Object) The present invention is made in view of the above problems, and provides a molten metal pressure feeding device which does not damage the plunger device even when the heating of the molten metal by the heater of the holding furnace is stopped. The purpose is.

(Structure) Hereinafter, the structure of the present invention will be described in detail with reference to the drawings.

(1) is a holding furnace to which a heater (not shown) is attached, and a cylinder tube (2) is vertically arranged in the holding furnace (1) through a supporting member (not shown). A pressure piston (3) is fitted in the tube (2) so as to be vertically slidable.

A frame (4) is provided at a position directly above the cylinder tube (2) above the holding furnace (1), and a fixing unit having a through hole (5) in the center is provided at the lower part of the frame (4). The support member (6) is suspended via the brackets (7) and (7).

A downward cylinder (8) is provided on the frame (4), and its piston rod (8a) is the fixed support member.
It extends loosely through the through hole (5) of (6) and extends below the fixed support member (6), and a stopper plate (9) is fixedly connected to the lower end thereof.

Further, an upper end of a connecting rod (10) is fixedly suspended from a lower portion of the stopper plate (9), and a lower end of the connecting rod (10) is fixedly connected to an upper surface of the pressure piston (3). .

Further, the fixed support member (6) includes a bolt (11a) and a nut.
A plurality of guide members (11) composed of (11b) are located on the outer circumference of the piston rod (8a), and their lower ends correspond to the stopper plate (9) (details will be described later) and can be raised and lowered. Between the fixed support member (6) and the lower end of the guide member (11), the total sum is larger than the ascending output of the downward cylinder (8). ) Is mounted.

Further, a first nozzle (13) extending in the horizontal direction is connected to the bottom of the cylinder tube (2) with one end thereof communicating, and the first nozzle (13) is connected from the upper part of the holding furnace (1) to the machine. A second nozzle (15) communicating with the outer mold (14) is connected for communication.

In the figure, (16) is a molten metal introduction hole, and (17) is a low melting point metal in a molten state (hereinafter referred to as molten metal).

Further, in FIG. 1, the pressurizing piston (3) is a downward cylinder (8).
Is located at the rising end by the lifting operation of
(9) contacts the lower ends of the guide members (11) and (11), and the coil spring (1
2) The repulsive force of (12) prevents the rise.

In this state, the piston of the downward cylinder (8) has a stroke margin larger than the amount of solidification and expansion in the vertical direction of the molten metal (17) in the cylinder tube (2), not at the rising end.

(Operation) In the structure configured as described above, the molten metal (17) is filled up to the upper position of the cylinder tube (2), the first nozzle (13) and the second nozzle (15) in FIG. .

In this state, the downward cylinder (8) operates and the pressure piston (3)
And the molten metal (17) in the second nozzle (15), the first nozzle (13) and the cylinder tube (2) is pressure-fed to the mold (14) and is also fed to the mold (14). Hold the molten metal (17) until it solidifies. The portion of the second nozzle (15) exposed from the holding furnace (1) is heated by a heater (not shown) so that the molten metal (17) in this portion does not solidify.

Next, when the downward cylinder (8) is reversely operated and the pressurizing piston (3) is pulled up to the position shown in FIG. 1, the stopper plate (9) is brought into contact with the lower ends of the guide members (11) and (11). At this time, the coil spring (1
2) Since the repulsive force of (12) is larger than the ascending force of the downward cylinder (8), the ascending of the piston rod (8a) is stopped here. At this time, the molten metal (17) flows from the molten metal introduction hole (16) into the cylinder tube.
Introduced in (2), the level is restored to the level before work.

Next, the core cast in the mold (14) is taken out, necessary work such as mold cleaning and mold matching is performed, the state of FIG. 1 is restored, and similar casting work is repeated.

In the state shown in Fig. 1, when the holding furnace (1) stops heating due to a power failure, disconnection, or some other abnormality, the molten metal (17) solidifies in the holding furnace (1) and the cylinder (2) The molten metal (17) also solidifies and expands and pushes the pressure piston (3) upward. Along with this, the stopper plate (9) has a coil spring (12).
The guide members (11) (11) are pushed up against the repulsive force of (12), and the piston rod (8a) of the downward cylinder (8) is also raised. Therefore, even if the molten metal (17) solidifies and expands in the cylinder tube (2), the downward cylinder (8) moves toward the piston rod (8
As a) is moved, it is possible to avoid deforming or damaging the cylinder tube (2), the downward cylinder (8) and the like. At this time, the force applied to the device is only the amount corresponding to the compression of the coil springs (12) (12), so that it does not become a large force and does not damage the device.

In the above embodiment, the coil springs (12) and (12) are elastically mounted on the outer circumference of the guide members (11) and (11), but the same applies even if the spring members are disc springs or rubber springs. The effect of is obtained.

(Effect) As is apparent from the above description, the present invention uses a spring member having a repulsive force to raise the piston rod of a cylinder for raising and lowering a pressure piston fitted in the cylinder cylinder. Since the structure for incorporating the stopping mechanism is incorporated, even if the low melting point metal is solidified and expanded by stopping the heating of the heater of the holding furnace, the device is not damaged.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of the present invention, FIG. 1 is a longitudinal sectional view, and FIG. 2 is an enlarged view of portion A in FIG. (1): Holding furnace, (2): Cylinder cylinder (3): Pressurizing piston, (8): Downward cylinder (8a): Piston rod, (9): Stopper plate (11): Guide member, (12 ): Coil spring

Claims (1)

[Scope of utility model registration request] 1. A nozzle for communicating a cylinder (2) inside a holding furnace (1) and a mold (14) arranged outside the holding furnace (1) at a lower position of the cylinder cylinder (2). (1
3) (15) are connected in communication, the pressurizing piston (3) is slidably fitted in the cylinder tube (2), and the cylinder tube (2) above the holding furnace (1) is fitted. The downward cylinder (8) is fixed to the position directly above via the frame (4), and the piston rod (8a) of the downward cylinder (8) is fixed.
A stopper plate (9) is fixed to the tip, and the stopper plate (9) is connected to the pressurizing piston (3) by a rod (10).
And the piston rod (8a) at a position between the frame (4) and the stopper plate (9).
The guide member (11) (11) can be moved up and down to the outer peripheral position via the fixed support member (6), and the piston of the downward cylinder (8) when the lower end thereof is the rising end of the pressurizing piston (3). The suspension plate (9) is hung so as to abut on the upper surface of the stopper plate (9) with a sufficient stroke margin, and is hung between the lower ends of the guide members (11) (11) and the fixed support member (6). A molten metal pressurizing and feeding device characterized in that spring members (12) (12) having a repulsive force whose total sum is larger than the ascending output of the downward cylinder (8) are mounted.