JP2883049B2 - Free arm centrifugal casting machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a free arm rotating mechanism of a high frequency induction heating type centrifugal casting machine.

[0002]

2. Description of the Related Art FIGS. 4 and 5 show the main parts of the prior art disclosed in Japanese Patent Publication No. 6-85988. The gist of the configuration is that the main arm is rotatably driven by the rotary drive mechanism K, the sub-arm is rotatably mounted on one end of the main arm so as to be rotatable in the horizontal direction, the crucible provided on the sub-arm, and the crucible. A mold provided with the spout facing the pouring spout, a stopper pin provided on each of the main arm and the sub-arm, and a stopper pin corresponding to each stopper pin, movable in the vertical direction, and associated with each stopper pin. And a stopper body that engages with the stopper body, and when the stopper pin of the main arm and the stopper pin of the sub arm are engaged together, the sub arm has an angle delayed with respect to the rotation direction of the main arm. It is set.

[0003] As described above, the reason for setting the sub-arm at an angle delayed with respect to the main arm in the initial stage of turning is that if the main arm and the sub-arm are started from a straight line, the crucible may be moved. In the initial stage of rotation when the centrifugal force does not act sufficiently, the direction in which the molten metal jumps out of the spout is delayed in the direction of rotation of the arm from the action of the centrifugal force and the molten metal spills out of the sprue. By setting the position of the sub-arm at an angle delayed from the rotation direction of the main arm as shown in FIG. When the rotation becomes constant speed, the main arm and the sub arm are aligned.

Although the above prior art invention is effective for preventing molten metal from spilling from the gate at the initial stage of arm rotation, the stopper pins of both the main arm and the sub arm are set once. It is troublesome because it is performed in two steps.

[0005]

SUMMARY OF THE INVENTION The present invention is an improvement of the prior art described above, in which the setting of the stopper pin is performed in only one step, and the effect of the prior art is maintained and the centrifugal centrifuge has a simple structure. An object of the present invention is to provide a rotary arm mechanism of a casting machine.

[0006]

In order to achieve the above object, a free-arm centrifugal casting machine according to the present invention comprises:
In a free-arm centrifugal casting machine in which metal in a crucible melted by a high-frequency induction coil is cast into a mold by centrifugal force, the free arm has a weight balancer at one end which is supported by a horizontal rotary drive shaft. A main arm and a sub-arm rotatably supported on a support shaft slightly inclined from a horizontal plane at the other end of the main arm;
A mold attached to the crucible with the spout facing the spout and a stopper pin provided downward at the end of the sub arm are attached to the sub-arm, and a high-frequency induction for melting the metal in the crucible is attached to the lifting frame. A coil and a stopper body having a hole that engages with the stopper pin are attached, and when the metal is melted, the lifting frame is raised to engage the stopper pin and the stopper body, and after melting, the lifting frame is lowered. This releases the engagement of the stopper pin to rotate the free arm.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to a first aspect of the present invention, a free arm is supported by a horizontal rotation drive shaft (hereinafter, referred to as a main shaft), and has a weight balancer at one end; At the other end, a sub-arm rotatably supported by a support shaft (hereinafter referred to as a sub-shaft) slightly inclined from the horizontal plane, a mold attached to the crucible with the spout facing the pouring spout, and a sub-arm A stopper pin provided downward at the end is attached, a high-frequency induction coil for melting the metal in the crucible, and a stopper body having a hole engaging with the stopper pin are attached to the lifting frame, At the time of melting, the lifting frame rises, the stopper pin and the stopper body engage, and the angle of the main arm and sub-arm viewed from the plane is counterclockwise from the center line of the main arm. To position the center line of the sub arm to a position of substantially 90 degrees, the metal dissolution is to perform pivoting of the free arm to disengage the lowered stopper pin and the stopper body lifting frame.

With the above configuration, the stopper pin can be set
It can be performed with only one stroke , and since the sub arm starts turning from the position delayed from the main arm, the molten metal is poured straight in the direction parallel to the pouring port of the crucible and the gate of the mold at the initial stage of turning. Thus, spillage of the molten metal can be prevented.

According to a second aspect of the present invention, the auxiliary shaft is inclined to the left by about 4 degrees from the main shaft provided vertically when viewed from the direction of the mold.

With the above arrangement, the sub arm comes to a position approximately 90 degrees counterclockwise from the main arm in the natural stop state after the rotation of the arm, and conversely, the sub arm turns from a position delayed by 90 degrees from the main arm. It will start, and will bring about the above-mentioned effects.

According to a third aspect of the present invention, the turning arm mechanism is provided in a vacuum device having an opening / closing lid.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. In FIG. 1 to FIG.
Is a main arm, a weight balancer 12 is provided at one end, and is supported by a horizontal rotation drive shaft, that is, a main shaft 14,
The other end of the main arm 11 is rotatably supported on a support shaft, that is, a sub shaft 15 so as to be rotatable in the horizontal direction together with the sub arm 16. The sub-arm 16 includes a crucible supporting table 17 and a crucible 1.
8 and a stopper pin 19 is attached to one end of the crucible support 17 in a downward direction. 21
Is a mold, and the crucible 1
Eight spouts are aimed. Reference numeral 13 is a balancer for adjustment.

When the stopper pin 19 is not engaged with the hole of the stopper body 26, the crucible support 17 is urged in the direction of the mold 21 by the spring 23. It fits in the gate. 22
Is a heat insulating material. When melting the metal, the lever L is moved in the direction opposite to the mold 21 (in the direction of the arrow in FIG. 2) by moving the crucible support 17 against the urging pressure of the spring 23, and the lifting frame 25 is raised to stop the stopper body 26. When the stopper pin 19 is engaged with the hole 27, the crucible 18 is accommodated in the high-frequency induction coil 24 provided on the lifting frame 25. The lifting frame 25 is raised and lowered by a lifting cylinder 28.

Although not shown, the free arm mechanism of this embodiment is provided in a vacuum apparatus having an opening / closing lid, and a pyroscope is provided above the opening / closing lid to adjust the melting temperature of the metal with the opening / closing lid closed. Detect and automatically raise / lower frame 25
, The main shaft 14 is driven to rotate and the free arm is rotated for a predetermined time , and then the drive is released and the casting is stopped naturally. In particular, crucible 1 for gold and silver
Since graphite is used for 8, vacuum melting is often performed. In the case of platinum, there are both in vacuum and in air.

When viewed from the end (mold side) of the sub arm 16, the sub arm is inclined approximately 4 degrees to the left, so that the sub arm 16 moves 90 degrees counterclockwise from the main arm 11.
When it is located at the angle of degrees, it will be in the lowest position and in the free state with the stopper pin 19 released, it will stop at that 90 degree position.

Therefore, the sub arm 16 is connected to the main arm 1
At 90 degrees counterclockwise from 1, the stopper pin 19 is engaged with the hole 27 of the stopper body 26 to energize the high-frequency induction coil 24 to melt the metal in the crucible 18 and then engage the stopper pin 19. When released, the sub-arm 16 starts to turn from the main arm 11 at a further 90 ° position. When the sub-arm 16 rotates at a constant speed, the main arm 11 and the sub-arm 16 are aligned. If the energization is stopped and the free rotation state is maintained, the sub arm 16
It naturally stops at a position 90 degrees counterclockwise with respect to 1.

In other words, from the position where the main arm 11 and the sub arm 16 are in a straight line, the sub arm 16
That is to start the rotation with a delay.

[0018]

According to the present invention, in a free-arm centrifugal casting machine in which a molten metal in a crucible on a free arm is poured into a mold to perform casting by generating a centrifugal force, the free arm is constituted by a main arm and a sub arm. in the start time of the rotation of the centrifugal force in the entire both arms is not for work, it is set to 90 degrees delayed angle from the main arm in a counterclockwise direction towards the sub-arm with respect to the rotational direction of the main arm
At the end of the rotation, a spontaneous stop at the original 90 ° delay
Since the stopper is stopped, the engagement and release of the stopper can be easily performed by an operation of only one stroke .

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is an explanatory diagram showing the operation of the above.

FIG. 4 is a plan view of a conventional example.

FIG. 5 is a front view of the same.

FIG. 6 is an explanatory view showing a direction in which a molten metal jumps out in a conventional example and an embodiment of the present invention.

Claims (3)

(57) [Claims] 1. A free-arm centrifugal casting machine in which metal melted in a crucible melted by a high-frequency induction coil is cast into a mold by centrifugal force. A main arm having a weight balancer, and a sub-arm is rotatably supported on a sub-axis at the other end of the main arm, and the sub-axis of the sub-arm includes a sub-arm and a main arm.
When viewed from the outer end of the sub-arm in a straight line, the sub-arm is provided to be inclined to the left, and the sub-arm has a crucible, a mold with a sprue directed toward the spout of the crucible, and a lower end of the sub-arm. A stopper pin is attached to the lower part of the portion, a high-frequency induction coil for melting the metal in the crucible, and a stopper body having a hole that engages with the stopper pin are attached to the lifting frame. At the start of arm rotation, the sub-arm rotates from a position delayed by 90 degrees counterclockwise with respect to the main arm. At constant speed rotation, the sub-arm is aligned with the main arm, and at the end of rotation, the sub-arm is counterclockwise with respect to the main arm. A free-arm centrifugal casting machine characterized by naturally stopping at a position at 90 degrees in the direction. 2. A free arm centrifugal casting machine of claim 1, wherein the auxiliary shaft Sa Buamu is being inclined pairs Shi approximately 4 degrees to the vertical line. 3. The free arm centrifugal casting machine according to claim 1, wherein a free arm mechanism is provided in a vacuum device having an opening / closing lid.