JPH11197816A - Casting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To apply an ordinary furnace having simple structure as a holding furnace and to improve the supplying accuracy of molten metal by calculating a stroke for supplying the molten metal from the position corresponding to the fixed molten metal surface of a piston based on a level signal of the fixed molten metal surface, controlling an actuator so that the piston drives with this stroke and supplying the molten metal into an injection sleeve. SOLUTION: The fixed molten metal surface M is detected with a level sensor 23 and also, the stroke S2 for supplying the molten metal from the position L2 corresponding to the fixed molten metal surface of the piston 13 with a calculating means 25 based on the input of this detected signal. The actuator 21 is controlled with a control means 26 so that the piston 13 drives with this stroke to supply the molten metal M into the injection sleeve 6. In this way, even in the case of varying the molten metal surface in the molten metal holding furnace 16, the supply of the fixed quantity of the molten metal M can be attained. Then, by a molten metal supplying means 9, the ordinary furnace can be used as the holding furnace 16, and the fixed molten metal surface furnace is unnecessary. Further, since the rapid molten metal discharge can be executed by lowering the piston 13, the separated molten metal discharging mechanism is unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casting apparatus in which a molten metal in an injection sleeve is filled in a cavity of a mold by a forward movement of a plunger tip which moves forward and backward in the injection sleeve, and is molded by pressing.

[0002]

2. Description of the Related Art A conventional casting apparatus is disclosed in Japanese Unexamined Utility Model Publication No. 3-62.
There is a casting apparatus disclosed in Japanese Patent No. 653.

[0003] This casting apparatus is a hot chamber type die casting machine, and an injection device arranged by immersing a lower part in a molten metal in a molten metal holding furnace has a hot water supply port connected to a cavity of a mold apparatus through a hot water supply pipe. The molten metal is supplied into the cavity by driving the injection device.

Another conventional casting apparatus has a hot water supply port opened in the middle of an injection sleeve communicating with a mold cavity, and a hot water supply pipe provided with an electromagnetic pump is connected to the hot water supply port. The molten metal is supplied to the injection sleeve through the hot water supply pipe and the hot water supply port by driving the electromagnetic pump, and the cavity is filled with the molten metal in the injection sleeve by the forward movement of the plunger tip moving forward and backward in the injection sleeve. Pressing and molding.

[0005]

However, in the conventional casting apparatus disclosed in the official gazette, the injection apparatus is developed for a hot chamber, and serves both as hot water supply and filling pressurization. There are problems that it is not suitable for high quality casting because it is difficult to increase the pressure to 300 kgf / cm ² or more, and that the amount of hot water supplied varies due to fluctuations in the level of the molten metal holding furnace.

In the conventional casting apparatus equipped with an electromagnetic pump, a sufficient casting pressure can be obtained by the plunger tip, but a constant level furnace, a furnace body moving / pressing device, and a rapid draining mechanism are required. This not only complicates the structure of the entire apparatus, but also has the problem that the accuracy of hot water supply is inferior to that of ladle hot water.

Accordingly, an object of the present invention is to provide a casting apparatus which can be used as a holding furnace, which can be an ordinary furnace having a simple structure, and which can improve hot water supply accuracy and perform both high pressure and laminar flow filling.

[0008]

In order to achieve the above object, the invention according to claim 1 has a hot water supply port opened in the middle of an injection sleeve communicating with a cavity of a mold, and the hot water supply means is provided in the hot water supply port. A hot water supply pipe having a hot water supply pipe is connected, and the molten metal is supplied to the injection sleeve through the hot water supply pipe by driving the hot water supply means, and the inside of the injection sleeve is moved forward and backward by the plunger tip moving forward and backward in the injection sleeve. In the casting apparatus, the molten metal is filled in the cavity and pressurized to form, and the hot water supply means forms a pump chamber having a piston at a lower part formed with a discharge port at an upper part and communicating with the discharge port, and A molten metal introduction path that opens at the lower limit position of the piston and communicates with the pump chamber and the outside, which is shut off by the piston after the initial rise thereof, is formed on a side wall of the pump chamber, The discharge port is connected to the hot water supply pipe, and the pump chamber is immersed at least in the molten metal of the molten metal holding furnace. The pump body is installed at an upper portion of the pump body and connected to the piston via a rod. A pump means comprising an actuator; a level sensor provided in the hot water supply pipe for detecting a constant surface level in the hot water supply pipe; and a position of a piston in the pump chamber by measuring a moving amount of the rod provided in the pump means. And a lower limit position of the piston and a position corresponding to the constant level of the piston according to the input of the detection signal of the stroke sensor. Calculating means for calculating a hot water supply stroke of the piston from a position, and the pump from the molten metal introduction path at a lower limit position of the piston. The molten metal introduced into the pipe is moved into the hot water supply pipe by raising the piston, the piston is stopped at a position corresponding to the constant molten metal level, and the piston is driven according to the hot water supply stroke to supply the molten metal to the injection sleeve. And the control means for controlling the actuator in accordance with the input signal from the arithmetic means.

According to the first aspect of the present invention, since the plunger tip driven by the injection cylinder is provided as a means for filling and pressing the molten metal into the cavity, the hot water supply means is dedicated to supplying the molten metal to the injection sleeve. Used as

In the hot water supply means, a level sensor detects a constant hot water level, and a hot water supply stroke from a position corresponding to the constant hot water level of the piston is calculated by a calculating means based on the input of the detection signal of the constant hot water level. Further, since the actuator is controlled by the control means so that the piston is driven at the calculated hot water supply stroke and the molten metal is supplied to the injection sleeve, the molten metal is injected into the injection sleeve irrespective of the fluctuation of the molten metal level in the holding furnace. Can be supplied quantitatively. As a result, this hot water supply means not only does not require a constant-temperature furnace, but also performs rapid drainage by lowering the piston of the pump chamber, so that a separate rapid drainage mechanism is not required.

The molten metal in the injection sleeve is filled in the cavity at high pressure and laminar flow by the forward movement of the plunger tip moving forward and backward in the injection sleeve.

According to a second aspect of the present invention, in the casting apparatus according to the first aspect, the pump means is swingably mounted around a swing fulcrum provided on a fixed die plate. It is characterized in that it is attached to the hot water supply pipe so as to be able to approach and separate from the hot water supply pipe by driving a swing cylinder which is attached to the fixed die plate and the pump means below the fulcrum.

According to the second aspect of the present invention, the pumping means can be separated from the hot water supply pipe by driving the swinging cylinder used for the support mechanism of the pump means to perform maintenance work, and the pump means can be supplied with hot water. It can be connected to a tube and set for use.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a casting apparatus 1 as one embodiment of the present invention. The casting apparatus 1 includes a mold cavity 2
A hot water supply port 7 is provided in the middle of an injection sleeve 6 communicating with the hot water supply port, and a hot water supply pipe 8 provided with a hot water supply means 9 is connected to the hot water supply port 7. The molten metal is supplied to the sleeve 6, and the inside of the injection sleeve 6 is moved forward,
The molten metal in the injection sleeve 6 is filled in the cavity 2 by pressurization by the forward movement of the plunger tip 10 moving backward, and is formed by molding. The cavity 2 is formed by closing a fixed mold 3 fixed to a fixed die plate 5 and a movable mold 4 moving forward and backward with respect to the fixed mold 3. The injection sleeve 6 is composed of a sleeve piece which is divided into two and fixed to the fixed mold 3 and the movable mold 4, respectively, and a hot water supply port 7 is formed in the sleeve piece fixed to the fixed mold 3. .

The hot water supply means 9 comprises a pump means 22 comprising a pump body 15 and an actuator 21, a level sensor 23, a stroke sensor 24, a calculation means 25, and a control means 26.

The pump body 15 has a discharge port 11 formed in the upper part and a pump chamber 12 provided with a piston 13 in the lower part in communication with the discharge port 11.
3 is formed in the side wall of the pump chamber 12 and opened at the lower limit position L1 of the pump chamber 12 and communicated with the outside of the pump chamber 12 by the piston 13 after the initial rise. Connected to the pump chamber 1
2 is immersed at least in the molten metal M of the molten metal holding furnace 16 and installed.

At this time, the pump chamber 12 is formed to have a U-shaped cross section by opening the lower end surface of the pump body 15, and is opened in the upper wall of the pump chamber 12 to communicate with the discharge port 11. 11 a and a rod insertion hole 15 a are formed in the axial direction of the pump body 15. The piston 13 closes the lower end of the pump chamber 12 at its lower limit position L1, and is provided so as to be vertically movable by sliding its outer peripheral surface against the inner wall surface of the pump chamber 12.

The molten metal introduction passage 14 is formed by a groove 14a formed in the lower inner wall surface of the pump chamber 12 and a piston 13 at a lower limit position L1 cooperating with each other. That is, the groove portion 14a is formed with the upper portion being somewhat higher than the upper surface of the piston 13 at the lower limit position L1 and the lower portion being opened to the lower end surface of the pump body 15, and the inner wall surface of the pump chamber 12 of the groove portion 14a. The molten metal introduction path 14 is configured to have an upper opening 14b that opens to the pump chamber 12 by closing the release portion on the side with the outer peripheral surface of the piston 13 and a lower opening 14c that opens to the outside.

The actuator 21 is provided on an upper part of the pump body 15 and is connected to the piston 13 via a rod 20. In this embodiment, the actuator 21 is attached via a cover 37 provided on the upper part of the pump body 15. Further, the rod 20 is connected to the piston rod 17 of the actuator 21 penetrating through the through hole 37a of the cover body 37, and is connected to the piston rod 17 via the coupling 18 at the upper end through the rod insertion hole 15a and at the lower end. And a connecting rod 19 connected to the piston 13.

As described above, the pump means 22 composed of the pump body 15 and the actuator 21 has the discharge port 11 higher than the highest molten metal level M 2 in the molten metal holding furnace 16 and the hot water supply pipe 8.
And the pump chamber 12 is installed so as to be immersed below the lowest molten metal level M3 in the molten metal holding furnace 16. Therefore, when the aluminum alloy is cast, the pump body 15, the piston 13, and the connecting rod 19 are formed using fine ceramics (for example, Si ₃ N ₄ or the like) which does not corrode the molten aluminum and is resistant to thermal shock. In the case of casting a Zn alloy or a Mg alloy, it is formed by using a heat-resistant alloy suitable for the melting point of each alloy.

The level sensor 23 is provided in the hot water supply pipe 8 so as to detect the constant hot water level M 1 in the hot water supply pipe 8. In the present embodiment, the level sensor 23 is provided in the hot water supply pipe 8 from the hot water supply port 7 of the injection sleeve 6, and is capable of detecting a constant level surface M1 having a level substantially equal to that of the hot water supply port 7.

The stroke sensor 24 is connected to the rod 2
The pump means 22 is provided so that the position of the piston 13 in the pump chamber 12 can be detected by measuring the movement amount of zero.
In the present embodiment, the stroke sensor 24 is attached to a boundary portion between the actuator 21 and the cover body 37, and is attached so that the movement amount of the piston rod 17 can be measured.

The calculating means 25 includes the stroke sensor 2
4, the lower limit position L1 of the piston 13 is determined.
In addition to storing the level L2 and the corresponding level L2, the level sensor 23 calculates a hot water supply stroke S2 of the piston 13 from the level L2 based on the input of the detection signal of the level M1. For this purpose, the calculating means 25
Are provided with necessary electronic components such as a central processing unit (CPU) and a memory.

Further, the control means 26 moves the molten metal M introduced into the pump chamber 12 from the molten metal introducing passage 14 at the lower limit position L 1 of the piston 13 into the hot water supply pipe 8 by raising the piston 13 and moves the piston 13 to a constant molten metal level. The actuator 21 is controlled in accordance with an input signal from the arithmetic means 25 so as to stop at the corresponding position L2 and drive the piston 13 in accordance with the hot water supply stroke S2 to supply the molten metal M to the injection sleeve 6. . This control means 26
For example, it is configured by a hydraulic circuit that controls the actuator 21.

Although the hot water supply means 9 is constructed as described above, preferably, the pump means 22 is attached to the hot water supply pipe 8 so as to be able to approach and separate from the hot water supply pipe 8 as in the present embodiment.

In this embodiment, the pump means 22 is swingably mounted around a swing fulcrum A provided on the fixed die plate 5, and the fixed die plate 5 and the pump means 22 are arranged below the swing fulcrum A. It is configured to be attached to and detachable from the hot water supply pipe 8 by driving a swing cylinder 28 that is attached to and attached to the hot water supply pipe 8.

That is, the pump means 22 pivotally supports one end of the support portion 30 provided on the fixed die plate 5 (oscillation fulcrum A) and the other end of the cover body 37 (not shown). The rod 27 and the support portion 31 provided on the fixed die plate 5 below the support portion 30 pivotally support the tip of the piston rod 28a (oscillation fulcrum B), and the cover body 37 pivotally supports the cylinder portion 28b ( (Not shown) Swing cylinder 2
8 and is supported. This swing cylinder 28
Control means 2 based on an input signal from push button switch 32
The drive is controlled via the control unit 6.

For this reason, when the piston rod 28a of the oscillating cylinder 28 advances, the pump means 22 rotates around the oscillating fulcrum A in a direction away from the hot water supply pipe 8 and is pulled up onto the molten metal holding furnace 16 ( When the piston rod 28a retreats, it rotates around the swing fulcrum A in a direction approaching the hot water supply pipe 8 to connect the discharge port 11 to the hot water supply pipe 8 in a liquid-tight manner. (Shown by a solid line in FIG. 1).

The driving mechanism of the plunger tip 10 in the casting apparatus 1 is the same as that of the prior art.
It is provided with.

That is, the driving mechanism is such that the plunger tip 10 connects the plunger rod 10 a to the injection cylinder 2.
9 is connected to the piston rod 29a of the No. 9 via a coupling 40, and the injection stroke sensor 34 detects the amount of movement of the magnetic scale 33 provided integrally with the coupling 40, thereby driving the injection cylinder 29. Control, whereby the driving of the plunger chip 10 is controlled.

In FIG. 1, reference numeral S1 denotes a stroke corresponding to a constant molten metal surface, reference numeral 35 denotes a jack for securing a normal posture of the molten metal holding furnace 16, and reference numeral 36 denotes a molten metal holding furnace 1.
6 shows an insulating lid covering the upper opening of No. 6.

Next, the operation of the casting apparatus 1 configured as described above will be described with reference to the flowchart shown in FIG.

The casting apparatus 1 has a discharge port 1 of a pump means 22.
1 and a hot water supply port 7 of the injection sleeve 6 are connected in a liquid-tight manner through a hot water supply pipe 8, and the piston 13 is moved to a lower limit position L1.
And the molten metal introduction path 14 is opened, and the molten metal M in the molten metal holding furnace 16 is opened through the released molten metal introduction path 14.
Is introduced into the pump chamber 12 (and also in the hot water duct 11a depending on the level of the molten metal in the molten metal holding furnace 16). The lower limit position L1 of the piston 13 at this time is the stroke sensor 2
4 and is stored in the calculating means 25.

First, in the previous cycle, the closed position L5 of the hot water supply port 7 was set.
The stopped plunger tip 10 is retracted (step 50), and the plunger tip 10 is moved to the retreat limit position L4.
(Step 51), the hot water supply port 7 is opened, and the fixed mold 3 and the movable mold 4 that have been opened in the previous cycle are closed (step 56).

When a stop confirmation signal (and a mold closing confirmation signal) at the retreat limit position L4 of the plunger tip 10 is input to the calculating means 25, the actuator 21 is driven via the control means 26 to raise the piston 13 of the pump body 15. (Step 52). After the initial rise of the piston 13, communication between the pump chamber 12 and the outside by the molten metal introduction path 14 is cut off, and the molten metal M in the pump chamber 12 and the molten metal conduit 11 a shifts to the hot water supply pipe 8 by the rise of the piston 13. .

At the transition of the molten metal M, the level sensor 23 detects the level M1 (step 53). When the level detection signal is input to the calculating means 25, the driving of the actuator 21 via the control means 26 is stopped. As a result, the piston 13 stops at the constant hot water level corresponding position L2 (step 5).
4). The position L2 corresponding to the constant temperature level is determined by the stroke sensor 24.
And stored in the calculating means 25. During this time, the piston 13 rises by a constant level corresponding stroke S1.

When a constant level detection signal from the level sensor 23 is input to the calculating means 25, the calculating means 25
The hot water supply stroke S2 from the constant hot water surface corresponding position L2 of No. 3 is calculated (step 55). After this calculation, a hot water supply start signal is input from the calculating means 25 to the control means 26 (step 5).
7) As a result, the actuator 21 is driven, and the piston 13 rises from the constant hot water level corresponding position L2 by the hot water supply stroke S2 (step 58). A desired amount of molten metal M is supplied into the injection sleeve 6 by the rise of the piston 13. The piston 13 stops at the upper limit position L3 of the hot water supply stroke S2 (step 59). Upper limit position L of this piston 13
3 is detected by the stroke sensor 24 and stored in the calculating means 25.

Next, the upper limit position stop confirmation signal (injection start signal) of the piston 13 is sent from the arithmetic means 25 to the injection cylinder 29.
Is input to the control means (not shown) (step 60).
And the injection cylinder 29 is driven in accordance with the same control process as in the prior art, whereby the plunger tip 10 is raised from the retreat limit position L4 by the injection stroke S3 (step 61) and the molten metal M in the injection sleeve 6 is transferred to the cavity 2. Pressurizing / filling (step 62) and the injection stroke S
(3) Stop at the upper limit position L6 and hold the pressure (step 6).
3) Then, it retreats (Step 64) and stops at the closed position L5 of the hot water supply port 7 (Step 65).

The injection stroke sensor 34 detects that the plunger chip 10 has closed the hot water supply port 7 when the plunger chip 10 is lifted in step 61. , The piston 13 is lowered (step 68) and stopped at the lower limit position L1 stored in the calculating means 25 (step 69). As the piston 13 descends, the molten metal M in the hot water supply pipe 8 is drained, and the lower limit position L1
Is stopped, the molten metal introduction path 14 is released, and the molten metal M in the molten metal holding furnace 16 is introduced into the pump chamber 12 (and also into the molten metal path 11a depending on the level of the molten metal in the molten metal holding furnace 16) (step). 70).

Further, after the molten metal M in the cavity 2 is solidified, the molds 3 and 4 are opened (step 66), and the product is extruded and taken out (step 67). In this step 67, the remaining molten metal of the molten metal M in the injection sleeve 6 is solidified into a biscuit, and is extruded together with the product.

Thus, one cycle of the operation of the casting apparatus 1 is completed. The casting apparatus 1 can continuously form products by repeating this cycle.

When the casting apparatus 1 needs maintenance, a signal is inputted by the push button switch 32. In response to an input signal from the push button switch 32, the control means 26 switches to a hydraulic circuit for maintenance and drives the swing cylinder 28. That is, the piston rod 28a of the oscillating cylinder 28 moves forward, whereby the pump means 22 in use is rotated about the oscillating fulcrum A in a direction away from the hot water supply pipe 8 and pulled up onto the molten metal holding furnace 16 (FIG. 1 is indicated by a two-dot chain line). Since the maintenance work can be performed in the raised state, the work can be easily performed.

After the maintenance work is completed, the piston rod 28a of the swing cylinder 28 is retracted again by the input signal of the push button switch 32, and the pump means 22 in the maintenance state is swung in the direction approaching the hot water supply pipe 8. By rotating around the fulcrum A, the discharge port 11 is connected to the hot water supply pipe 8 in a liquid-tight manner (shown by a solid line in FIG. 1). Thereby, the pump means 22
Since the use state of (1) is obtained, the moving / pressing device of the furnace required in the past becomes unnecessary, and the structure of the entire device can be simplified.

According to such a casting apparatus 1, the injection cylinder 2 is used as a means for filling and pressing the molten metal M into the cavity 2.
Since it has a plunger chip 10 driven by 9,
Hot water supply means 9 is used exclusively for supplying hot metal M to injection sleeve 6. For this reason, the casting apparatus 1 is capable of filling the cavity 2 with the molten metal M under high pressure and laminar flow, thereby achieving high quality casting. For example, squeeze casting with a casting pressure of 1000 kgf / cm ² or more is possible.

At this time, the hot water supply means 9 detects the constant molten metal level M1 by the level sensor 23, and based on the input of the detection signal of the constant molten metal level M1, the arithmetic means 25 calculates the position L2 of the piston 13 corresponding to the constant molten metal level. Is calculated and the control means 26 controls the actuator 21 to supply the molten metal M to the injection sleeve 6 so that the piston 13 is driven in the hot water supply stroke S2. The fixed amount of the molten metal M can be supplied to the injection sleeve 6 irrespective of the fluctuation of the molten metal level in the inside. Hot water supply accuracy can be improved to ± 1%, for example, compared to ± 3% in the past. In addition, the hot water supply means 9 not only makes the holding furnace 16 compatible with an ordinary furnace having a simple structure, but also eliminates the need for a constant temperature furnace,
Rapid hot water discharge is also performed by lowering the piston 13 of the pump chamber 12, so that a separate quick water discharge mechanism is not required, thereby simplifying the overall structure.

[0047]

As described above, according to the first aspect of the present invention, since the plunger tip driven by the injection cylinder is provided as means for filling and pressing the molten metal into the cavity, the hot water supply means applies the molten metal to the injection sleeve. Is used exclusively for supplying hot water to the cavities, so that high-pressure, laminar-flow filling of the molten metal into the cavities becomes possible, thereby achieving high-quality casting.

In addition, the hot water supply means at this time detects the constant hot water level by the level sensor and calculates the hot water supply stroke from the position corresponding to the constant hot water level of the piston by the arithmetic means based on the input of the detection signal of the constant hot water level. The actuator is controlled by the control means so that the piston is driven at the calculated and the calculated hot water supply stroke, and the molten metal is supplied to the injection sleeve. In addition to improving the accuracy of hot water supply by enabling a constant supply of molten metal to the furnace, the holding furnace can be replaced with a simple furnace with a simple structure, eliminating the need for a constant-temperature furnace, and rapidly discharging the piston by lowering the piston in the pump chamber. Since hot water is also provided, a rapid hot water discharge mechanism as a separate mechanism is not required, and the structure of the entire apparatus can be simplified.

According to the second aspect of the present invention, the pumping means can be separated from the hot water supply pipe by driving the swinging cylinder used for the support mechanism of the pump means, so that maintenance work can be performed. Can be set to the use state by connecting to
A pressing device is not required, and the structure of the entire device can be simplified.

[Brief description of the drawings]

FIG. 1 is a sectional view of a casting apparatus as one embodiment of the present invention.

FIG. 2 is a flowchart illustrating the operation of the casting apparatus of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Casting apparatus 2 Cavity 3 Fixed die (die) 4 Movable die (die) 5 Fixed die plate 6 Injection sleeve 7 Hot water supply port 8 Hot water supply pipe 9 Hot water supply means 10 Plunger tip 11 Discharge port 12 Pump room 13 Piston 14 Melt Introducing path 15 Pump body 16 Molten holding furnace 20 Rod 21 Actuator 22 Pump means 23 Level sensor 24 Stroke sensor 25 Calculation means 26 Control means 28 Swing cylinder A Swing fulcrum L1 Lower limit position (of piston) L2 Constant position corresponding to fixed metal surface ( Of piston) M molten metal M1 constant level S2 hot water supply stroke

Claims (2)

[Claims] 1. A hot water supply port having an opening in the middle of an injection sleeve communicating with a cavity of a mold, and a hot water supply pipe having a hot water supply means is connected to the hot water supply port, and the hot water supply means is driven by driving the hot water supply means. A casting apparatus for supplying molten metal to the injection sleeve via a pipe, filling the cavity with the molten metal in the injection sleeve by the forward movement of a plunger tip that moves forward and backward in the injection sleeve, and pressurizes and forms the molten metal; Forming a discharge port at the upper part and communicating with the discharge port to form a pump chamber having a piston at the lower part, and opening at the lower limit position of the piston, and being shut off by the same piston after the initial rising thereof. A molten metal introduction path communicating the pump chamber with the outside is formed on a side wall of the pump chamber, and the discharge port is connected to the hot water supply pipe and the pump chamber is reduced. Pump means comprising a pump body immersed and installed in the molten metal of the molten metal holding furnace, an actuator provided on an upper part of the pump body and connected to the piston via a rod, and a pump means provided on the hot water supply pipe. A level sensor for detecting a constant hot water level in the hot water supply pipe; a stroke sensor provided in the pump means for measuring a movement amount of the rod to detect a position of a piston in the pump chamber; and inputting a detection signal of the stroke sensor. By storing the lower limit position of the piston and the position corresponding to the constant temperature surface,
A calculating means for calculating a hot water supply stroke of the piston from a position corresponding to the constant molten metal level by inputting a detection signal of the constant molten metal level from the level sensor; Moving the molten metal into the hot water supply pipe by raising the piston, stopping the piston at a position corresponding to the constant temperature surface, and driving the piston according to the hot water supply stroke to supply the molten metal to the injection sleeve. And a control means for controlling the actuator according to an input signal from the arithmetic means. 2. The casting apparatus according to claim 1, wherein said pump means is swingably mounted around a swing fulcrum provided on a fixed die plate, and said pump is fixed below said swing fulcrum. A casting apparatus characterized in that the casting apparatus is detachably attached to the hot water supply pipe by driving a swing cylinder attached to a die plate and a pump means.