JPH08164462A - Pressure casting method - Google Patents

Abstract

PURPOSE: To shorten the cycle time of casting while surely preventing the development of defects of shrinkage hole, blow hole, etc. CONSTITUTION: A solenoid switch valve 40 is closed at the time of starting the pressure casting to hold the condition, in which the cooling water is not fed to a cooling water passage 12. After passing a prescribed time from the filling-up of molten metal into a cavity 10, a pressurizing pin 28 is advanced at slow speed together with a hydraulic piston 24 and the detection of solidified condition of the molten metal is started, and at the same time, the passing time T2 is measured with a counter in the control computer 50. At the point of time when the received pressure of the pressurizing pin 28 reaches the setting pressure, the pressurization of the molten metal is started and at a specific time later, the pressurizing pin 28 is stopped to complete the pressurization. At this time, the passing time T2 is calculated and in the case of being less than the setting time T1, the casting at the following time is executed in the condition of feeding no cooling water. On the other hand, in the case of being T1<=T2, the solenoid switch valve 40 is opened to supply the cooling water, and the casting at the following time is executed while cooling a casting metallic mold 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure casting method in which a molten metal filled in a cavity is solidified by a pressure pin when the molten metal is solidified. The present invention relates to a pressure casting method for detecting a solidification state of a molten metal based on a repulsive force received by a cylinder and determining a timing for applying pressure.

[0002]

2. Description of the Related Art In casting techniques such as die casting,
In order to prevent the occurrence of defects such as shrinkage and cavities that accompany the solidification and contraction of the molten metal, pressure casting is performed to press the molten metal in the stage where the molten metal filled in the cavity solidifies. In order to perform effective pressurization in such pressure casting, it is extremely important to appropriately set the timing for operating the pressurizing means such as the pressurizing pin. Therefore, a method for appropriately setting the timing of pressurization by the pressurizing pin has been developed, one example of which is disclosed in JP-A-4-182053.
No. 6,086,045. In the technique described in this publication, after the molten metal is filled, the pressurizing pin is moved forward at a slight speed by the pressurizing pin driving hydraulic cylinder. Then, when the repulsive force received by the pressure pin exceeds a predetermined pressure, it is determined that the molten metal is in a predetermined solidified state, and the pressure pin is advanced at a high speed to apply pressure. In this way, the pressurizing timing is determined by the repulsive force received by the pressurizing pin that moves forward at a slow speed, and pressurizing casting is performed.

[0003]

However, in the case of continuous casting in the prior art, the time required for the molten metal to reach a predetermined solidified state because the temperature of the casting mold gradually rises. It gets longer and longer. Therefore, the time required until the pressurization is actually started also increases with the number of castings, the casting cycle time becomes long, and the casting efficiency decreases. On the other hand, if the time from mold clamping to mold opening of the casting mold is kept constant in order to ensure casting efficiency, the time until pressurization will gradually increase, resulting in a stage where pressurization is not completed. The mold will be opened. For this reason, there is a problem that the proportion of defective products in which defects such as shrinkage and cavities are not completely crushed increases.

Therefore, in the inventions according to claims 1 and 2 of the present application, the pressure casting method capable of shortening the cycle time of casting while surely preventing the occurrence of defects such as shrinkage and cavities. The purpose is to provide. Also,
An object of the invention according to claim 2 is to provide a pressure casting method capable of realizing efficient pressure casting by controlling the casting cycle time more accurately and precisely.

[0005]

In order to solve the above problems, therefore, in the invention according to claim 1, the pressurizing pin is moved at a very low speed when the molten metal filled in the cavity of the casting mold is solidified. A pressurizing timing determining step of determining the timing of pressurizing by advancing and detecting the solidification state of the filled molten metal from the repulsive force received by the pressurizing pin, and the pressurizing at the determined pressurizing timing. In a pressure casting method including a pressurizing step of advancing a pin at a high speed to pressurize, a step of measuring a time required from the start of the pressurizing time determination step to the end of the pressurizing step, and the measurement And a step of cooling the casting mold in the vicinity of the cavity pressurized by the pressure pin when the required time is equal to or longer than the set time.

Further, in the invention according to claim 2, the pressure pin is advanced at a very low speed when the molten metal filled in the cavity of the casting die is solidified, and the repulsion force received by the pressure pin causes the filling. A pressurizing time determining step of determining a pressurizing time by detecting a solidified state of the molten metal, and a pressurizing step of advancing the pressurizing pin at high speed at the determined pressurizing timing to pressurize In the pressure casting method having, a step of measuring a time required from the start of the pressure timing determination step to the end of the pressure step, and a degree of cooling depending on the length of the measured time required. And a step of cooling the casting mold in the vicinity of the cavity pressurized by the pressure pin.

[0007]

In the pressure casting method according to the first aspect of the present invention, the pressure pin is advanced at a slow speed when the molten metal filled in the cavity is solidified, and the repulsive force received by the pressure pin is charged. The timing of pressurization is determined by detecting the solidified state of the molten metal. Then, the pressurizing pin is advanced at a high speed at the determined pressurizing time to perform pressurization. Here, from the start of the pressurizing timing determination step of advancing the pressurizing pin at a slow speed,
The time required to complete the pressurizing step of advancing the pressurizing pin at high speed is measured. Then, when the measured required time becomes equal to or longer than a preset set time, the casting die is cooled in the vicinity of the cavity pressurized by the pressure pin. The fact that the required time is longer than the set time means that the casting mold has been heated to a temperature higher than a predetermined appropriate temperature, and thus the time required for the molten metal to reach a solidified state where it can be pressurized has become longer. Therefore, by cooling the casting mold in the vicinity of the cavity to be pressurized, the time required for the molten metal in the pressurized portion to reach a predetermined solidified state can be shortened, and the required time can be shortened.
This will reduce the casting cycle time. In this way, the pressure casting method is capable of shortening the cycle time of casting while surely preventing the occurrence of defects such as shrinkage and cavities.

Further, in the pressure casting method according to the second aspect of the present invention, the time required from the start of the pressure timing determining step to the end of the pressure step is measured as in the pressure casting method of the first aspect. To be done. Then, the degree of cooling is changed according to the length of the measured required time, and the casting mold is cooled in the vicinity of the cavity pressed by the pressing pin. That is, if the measured required time is long, it means that the time required for the casting die to cool to a solidified state where the temperature of the casting die becomes higher and the molten metal can be pressurized, the casting die is more suitable. It is cooled strongly. Further, when the required time is short, it means that the casting die is at a relatively low temperature, and therefore the casting die is cooled slowly. As described above, in the pressure casting method according to the second aspect, the degree of cooling of the casting mold is adjusted according to the temperature of the casting mold indicated by the length of the required time. As a result, the time required for the molten metal to be cooled to a solidified state where it can be pressurized is controlled to an appropriate time that is neither too long nor too short. In this manner, the pressure casting method can realize more efficient and precise control of the casting cycle time to realize efficient pressure casting.

[0009]

【Example】

First Embodiment Next, a first embodiment embodying the present invention will be described with reference to FIGS. 1 and 2. This embodiment mainly corresponds to the invention of claim 1. First, the overall configuration of the pressure casting apparatus used in the pressure casting method of this embodiment will be described with reference to FIG. As shown in FIG.
Pressure casting apparatus 2 used in the pressure casting method of this embodiment
Has a casting mold 4. The casting die 4 is composed of a movable die 6 and a fixed die 8. By combining the movable die 6 and the fixed die 8, a cavity 10 corresponding to the product shape is formed inside. Molten metal is injected into the cavity 10 through a gate, a runner, and a gate (not shown). A pressure pin 28 is slidably penetrated through the movable die 6, and a tip 28 a of the pressure pin 28 faces the cavity 10 and forms a part of the cavity 10. The pressurizing pin 28 is integrated with the piston rod 26, and the rear end of the piston rod 26 is fixed to the hydraulic piston 24 of the pressurizing hydraulic cylinder 20. And the pressure pin 2
8 moves forward and backward integrally with the hydraulic piston 24 by the operation of the hydraulic system of the pressure casting device 2.

The hydraulic system of the pressure casting device 2 includes a hydraulic pressure source,
It is composed of an electromagnetic directional valve for hydraulic pressure, an electromagnetic on-off valve for hydraulic pressure, a flow rate adjusting valve for hydraulic pressure, and hydraulic piping connecting these (all are not shown). The pressure oil of the hydraulic pressure generation source passes through these hydraulic systems and is supplied to the rear chamber 22 of the pressurizing hydraulic cylinder 20.
A or the front chamber 22B. When the pressure oil flows into the rear chamber 22A, the pressure pin 28 moves forward integrally with the hydraulic piston 24, and the pressure pin tip 28a moves in a direction to enter the cavity 10. On the other hand, when the pressure oil flows into the front chamber 22B, the pressure pin 28 retracts integrally with the hydraulic piston 24, and the pressure pin tip 28a moves in the direction of coming out of the cavity 10.

When the hydraulic electromagnetic on-off valve is opened, a large amount of pressure oil is supplied to the rear chamber 22A, and the pressurizing pin 28 advances at high speed. On the other hand, when the hydraulic electromagnetic on-off valve is closed, a small amount of pressure oil is supplied to the rear chamber 22A only from the hydraulic flow rate adjusting valve, and the pressurizing pin 28 advances at a slight speed. As described above, the forward speed of the pressurizing pin 28 is controlled by opening and closing the hydraulic electromagnetic on-off valve. Further, a pressure sensor is attached to the aforementioned hydraulic system, and the magnitude of the hydraulic pressure applied to the rear chamber 22A of the pressurizing hydraulic cylinder 20 by this pressure sensor,
That is, the pressure received by the pressure pin 28 is measured. The measurement data obtained by this pressure sensor is input to the control computer 50 via a measurement signal line.

Further, inside the movable die 6, in the vicinity of the pressure pin 28 side of the cavity 10, the cooling water passage 12 is provided.
Is provided. The cooling water passage 12 is connected to the cooling water supply system of the pressure casting device 2. Pressure casting equipment 2
The cooling water supply system includes a cooling water pressure pump 30, an electromagnetic opening / closing valve 40, and cooling water pipes 32A, 32B connecting these components.
It is composed of 32C, 32D and the like. The cooling water pumped from the cooling water pressure pump 30 is guided to the inlet 14 of the cooling water passage 12 via the cooling water pipe 32A, the electromagnetic opening / closing valve 40, and the cooling water pipe 32B. On the other hand, a cooling water pipe 32C is connected to the outlet 16 of the cooling water passage 12 to form a cooling water path that returns to the cooling water tank 34 via the electromagnetic opening / closing valve 40 and the cooling water pipe 32D. The solenoid on-off valve 40 has a control computer 50 through a control signal line 54.
It is activated by a control signal sent from.

The solenoid on-off valve 40 has two valve chambers 44A and 44A.
B, and when the electromagnetic solenoid 42 is inactive, the repulsive force of the spring 46 causes the valve chamber 4 to be closed.
4B is connected to the pipe 32A (state shown in FIG. 1). When the electromagnetic solenoid 42 is excited by the control signal from the control computer 50, the valve chambers 44A, 44B
Moves against the repulsive force of the spring 46, and the valve chamber 44A in the open state is connected to the pipes 32A, 32B, 32C, 32D. As a result, the pressure cooling water from the pipe 32A is supplied to the inlet 14 of the cooling water passage 12 from the pipe 32B through the valve chamber 44A. Then, passing through the inside of the cooling water passage 12, from the outlet 16 to the pipe 32C, the valve chamber 44A, the pipe 32
It is returned to the cooling water tank 34 via D.

The control computer 50 has a memory 52.
The memory 52 stores the set time T1. In addition, the measurement value of the required time T2 is stored in the memory 52. When the temperature of the casting die 4 is a predetermined appropriate temperature, the set time T1 is after the pressurization pin 28 is started after the solidification state detection by the fine speed advance of the pressurization pin 28 is started.
This is the time required to complete the pressurizing process of the molten metal according to. On the other hand, the required time T2 is the time required from the start of the advance of the pressurizing pin to the completion of the pressurizing process in the actual casting, and the required time T2 is measured by the counter in the control computer 50. Done. And
As will be described later, these set time T1 and required time T2
Are compared in the control computer 50.

Now, the procedure of pressure casting using the pressure casting apparatus 2 having the above structure will be described with reference to FIG. 1 and according to the flowchart of FIG. FIG. 2 shows a casting procedure for each time when pressure casting is continuously performed. Before the pressure casting is started, the hydraulic piston 24 of the pressurizing hydraulic cylinder 20 is in the retracted position, and therefore the pressure pin 28 is also in the retracted position. Further, the electromagnetic opening / closing valve 40 has a valve chamber 44 as shown in FIG.
B is connected to each of the pipes 32A, 32B, 32C, 32D and is in a closed state. Step S10 in FIG.
When the control of pressure casting is started in, the cooling control of the casting mold is started at the same time (step S12). First,
At the start of the pressure casting, the electromagnetic on-off valve 40 is closed and the cooling water is not sent (step S).
14). In this state, the molten metal is filled. That is, an injection plunger (not shown) advances to fill the molten metal into the cavity 10 through the gate, runner, and gate of the casting mold 4 (step S16).

After a predetermined time has passed from the completion of filling,
The operation of detecting the solidification state of the molten metal by the pressure pin 28 is started (step S18). That is, a small amount of pressure oil is supplied to the rear chamber 22A of the pressurizing hydraulic cylinder 20 from the hydraulic pressure generation source, and the pressurizing pin 28 integrally with the hydraulic piston 24 starts moving at a slight speed toward the inside of the cavity 10. At the same time, the counter in the control computer 50 starts measuring the required time T2. Subsequently, it is determined whether or not the pressure received by the pressurizing pin 28 (that is, the measured value by the pressure sensor attached to the hydraulic system) has reached the set pressure, and when the set pressure is reached, pressurization of the molten metal is started. To be done.
That is, a large amount of pressure oil is supplied to the rear chamber 22A of the pressurizing hydraulic cylinder 20, and the pressurizing pin 28 advances at high speed to pressurize the molten metal in the cavity 10. After a fixed time from the start of pressurization, the hydraulic system is controlled by the control computer 50, the pressurizing pin 28 is stopped, and the pressurization ends.
At the same time, the measurement data of the required time T2 is stored in the memory 52 of the control computer 50, and the required time T2 is calculated (step S20).

Next, it is judged whether or not the operation of continuous casting is finished (step S22). When the casting operation is to be ended (YES), the control of the pressure casting is ended as it is (step S28). On the other hand, when the casting operation is continued (NO), the control computer 50 compares the set time T1 with the required time T2 (step S24). Then, when the required time T2 is less than the set time T1 (NO), the temperature of the casting mold 4 is less than the predetermined appropriate temperature, and thus step S1
Return to 4 and step S without cooling water being sent
The next casting will be performed after 16th. On the other hand, when the required time T2 is equal to or longer than the set time T1 (YES), it means that the temperature of the casting mold 4 has become equal to or higher than a predetermined appropriate temperature, so the process proceeds to step S26 and the cooling water is performed. Is started to be supplied. That is, the valve chamber 44A of the electromagnetic opening / closing valve 40 is connected to the pipes 32A, 32B, 32C, 32D and opened, and the cooling water is supplied from the inlet 14 into the cooling water passage 12. As a result, in the vicinity of the cavity 10 of the movable mold 6,
That is, the vicinity of the portion pressurized by the pressure pin 28 is cooled. Then, returning to step S16, the next casting is performed while cooling the movable mold 6.

In this way, until the casting operation is completed in step S22, casting is performed each time the required time T2 is compared with the set time T1, and when T1≤T2, cooling water is caused to flow and the casting mold is made. 4 is cooled, and if T1> T2, cooling is stopped. As described above, in the pressure casting method of the present embodiment, when the required time T2 becomes the set time T1 or more, that is, when the casting die 4 is heated to a predetermined appropriate temperature or more, Continuous casting is performed while cooling the casting die 4 in the vicinity of the pressurized cavity 10. As a result, the time required for the molten metal in the pressurized portion to reach a predetermined solidified state is shortened, the required time T2 can be shortened, and the casting cycle time can be shortened. In this way, it is possible to reliably prevent the occurrence of defects such as shrinkage and cavities while shortening the casting cycle time, and it is possible to efficiently obtain high-quality cast products without shrinkage and cavities.

Second Embodiment Next, a second embodiment embodying the present invention will be described with reference to FIGS. 3 and 4. This embodiment mainly corresponds to the invention of claim 2. First, the overall configuration of the pressure casting apparatus used in the pressure casting method of this embodiment will be described with reference to FIG. As shown in FIG.
The structure of the pressure casting device 62 of this embodiment is almost the same as that of the pressure casting device 2 of the first embodiment. The difference from the first embodiment is that
An electromagnetic flow rate adjusting valve 80 is provided in the cooling water supply system instead of the electromagnetic opening / closing valve 40. The electromagnetic flow rate adjusting valve 80 can continuously adjust the flow rate of the cooling water that is pressure-fed from the cooling water pressure pump 70 through the cooling water pipe 72A. The cooling water whose flow rate is adjusted is the cooling water pipe 72.
It is led to the inlet 14 of the cooling water passage 12 via B and the outlet 1
6 is returned to the cooling water tank 74 via the cooling water pipe 72C. The flow rate is adjusted by increasing or decreasing the degree of excitation of the electromagnetic solenoid 82 by a control signal sent from the control computer 90 through the control signal line 94 to change the electromagnetic flow rate adjusting valve 80.
It is performed by controlling the opening degree of. The measured time T2 is stored in the memory 92 of the control computer 90.
The data of is stored. Other mold structures and pressure pins 2
Since the advancing / retreating mechanism of 8 is the same as that of the first embodiment,
The same reference numerals are given and the description is omitted.

Now, the procedure of pressure casting using the pressure casting apparatus 62 having the above structure will be described with reference to FIG. 3 and according to the flowchart of FIG. FIG.
When the control of the pressure casting is started in step S30, the cooling control of the casting mold is started at the same time (step S3).
2). First, at the start of pressure casting, the opening of the electromagnetic flow rate adjusting valve 80 is adjusted to the minimum, and the cooling water having the minimum flow rate V1 is supplied from the inlet 14 to the cooling water passage 12 through the pipe 72B.
Is supplied to the inside (step S34). As a result, the vicinity of the cavity 10 of the movable mold 6 is slightly cooled.
In this state, an injection plunger (not shown) advances to pass through the sprue, runner, and gate of the casting mold 4 and the cavity 10
The inside is filled with the molten metal (step S36). After a lapse of a predetermined time from the completion of filling, detection of the solidified state of the molten metal by the pressing pin 28 is started (step S38). That is,
A small amount of pressure oil is supplied to the rear chamber 22A of the hydraulic cylinder 20 for pressurization, and the pressurizing pin 28 starts moving forward at a low speed. At the same time, the counter in the control computer 90 causes the time T
The measurement of 2 is started.

Subsequently, it is judged whether or not the pressure received by the pressurizing pin 28 has reached the set pressure, and when the set pressure is reached, a large amount of pressure oil is supplied to the rear chamber 22A of the pressurizing hydraulic cylinder 20. The pressurizing pin 28 advances at high speed to pressurize the molten metal in the cavity 10. Then, after a certain period of time, the pressurizing pin 28 is stopped by the control of the hydraulic system to complete the pressurization, and the measurement data of the required time T2 is obtained by the control computer 90.
Is stored in the memory 92 and the required time T2 is calculated (step S40). Next, the control computer 90 calculates an appropriate value of the cooling water flow rate V2 according to the value of the required time T2. This calculation is executed based on a relational expression which is empirically obtained in advance and stored in the memory 92 of the control computer 90. Then, the vicinity of the cavity 10 of the movable die 6 is cooled with the calculated cooling water flow rate V2 (step S42). That is, the electromagnetic flow rate adjusting valve 8
The opening degree of 0 is adjusted, and the cooling water having the flow rate V2 is supplied into the cooling water passage 12.

Then, it is judged whether or not the continuous casting operation is to be ended (step S44), and when the casting operation is ended, the pressure casting control is also ended (step S4).
6). On the other hand, if the casting operation is to be continued, step S
Returning to 36, the next casting is performed with the vicinity of the cavity 10 of the movable mold 6 being appropriately cooled. In this way, the casting is performed while the flow rate V2 of the cooling water is adjusted according to the measured value of the required time T2 every time until the casting operation is completed in step S44. As described above, in the pressure casting method of the present embodiment, the degree of cooling of the casting mold 4 is adjusted according to the temperature of the casting mold 4 indicated by the length of the required time T2. As a result, the time required for cooling the molten metal to a solidified state where it can be pressurized is controlled to an appropriate time that is neither too long nor too short. In this way, it is possible to more reliably and precisely reduce the cycle time of casting while reliably preventing the occurrence of defects such as shrinkage and cavities, and it is possible to efficiently produce high-quality cast products without shrinkage and cavities. Can be obtained.

In each of the above embodiments, as a method for cooling the vicinity of the cavity 10 of the movable die 6 of the casting die 4,
Although the cooling water passage 12 is provided in the movable mold 6 and the cooling water is supplied by the cooling water supply system, another cooling method can be used. For example, a method of flowing another cooling medium such as oil, liquid nitrogen, or low-temperature air into the passage 12, or blowing a cooling medium such as water, liquid nitrogen, or low-temperature air from the outside of the casting mold 4 (particularly the movable mold 6). Method etc. Further, although the pressurizing hydraulic cylinder 20 and the hydraulic piston 24 are used as the driving means for moving the pressurizing pin 28 forward, other fluid cylinder mechanism such as an air cylinder, an electric motor such as a hydraulic motor, or an electric motor is used. Other driving means such as a simple driving mechanism may be used. Further, as means for measuring the repulsive force received by the pressurizing pin 28, in addition to the pressure sensor attached to the hydraulic system, a pressure sensor attached to a piping system such as an air cylinder, a temperature sensor,
The pressure of a torque meter provided in a rotary drive mechanism such as an ultrasonic sensor, a hydraulic motor, an electric motor, etc., a power meter provided in an electric circuit, an ammeter, or a load cell provided directly on the pressurizing pin 28. A sensor or the like can be used.
Further, as the method of filling the molten metal into the cavity in the pressure casting, various casting methods such as gravity casting, reduced pressure casting, differential pressure casting, die casting and the like are included. The contents of the other steps of the pressure casting method and the configurations, shapes, sizes, materials, numbers, connection relationships, etc. of the other parts of the pressure casting apparatus are not limited to the above embodiments. .

[0024]

According to the first aspect of the invention, when the total time required for the pressurizing time detection step and the pressurizing step by the pressurizing pin is longer than the set time, the press die is cooled. As a result, it is possible to prevent the time required for the molten metal to reach a solidified state in which the molten metal can be pressurized from being lengthened, and the casting cycle time is reliably shortened. This makes it possible to pressurize the molten metal sufficiently in a short time, and it is a practical pressure casting method that can efficiently obtain a high-quality cast product without shrinkage, cavities, and the like.

According to the second aspect of the present invention, the pressurization for changing the cooling degree of the casting mold is performed according to the total length of the pressurizing timing detection step and the pressurizing step using the pressurizing pin. Due to the creation of the casting method, the time required for the molten metal to be cooled to a solidified state where it can be pressed is controlled to an appropriate time that is not always too long and not too short. In this way, a highly practical pressure casting method can be obtained in which the casting cycle time can be controlled more accurately and precisely and a high quality casting product can be obtained stably and efficiently.

[Brief description of drawings]

FIG. 1 is a diagram showing the overall configuration of a pressure casting apparatus in Example 1 of a pressure casting method according to the present invention.

FIG. 2 is a flowchart showing a procedure of pressure casting in Example 1 of the pressure casting method.

FIG. 3 is a diagram showing an overall configuration of a pressure casting apparatus in Embodiment 2 of the pressure casting method according to the present invention.

FIG. 4 is a flowchart showing a procedure of pressure casting in Example 2 of the pressure casting method.

[Explanation of symbols]

 2 Pressure casting device 4 Casting die 10 Cavity 28 Pressure pin T1 setting time T2 Required time

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoya Yamamoto 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Mitsuru Inui 1-9-6 Rokujo Minami, Gifu City, Gifu Prefecture Gifu Seiki Industrial Co., Ltd. Company 1st Business Department (72) Inventor Kento Nimura 1-9-6 Rokujo Minami Gifu City Gifu Prefecture 1-9-6 Gifu Seiki Kogyo Co., Ltd. (72) Akira Saito 1-9 Rokujo Minami Gifu City Gifu Prefecture 6 Gifu Seiki Industry Co., Ltd. 1st Division

Claims (2)

[Claims] 1. The solidification state of the filled molten metal is detected from the repulsive force received by the pressure pin by advancing the pressure pin at a slow speed at the stage where the molten metal filled in the cavity of the casting mold is solidified. In a pressure casting method, which comprises a pressure timing determining step of determining the timing of pressurizing, and a pressure step of advancing the pressure pin at high speed at the determined pressure timing to perform pressure, Measuring the time required from the start of the pressurizing time determining step to the end of the pressurizing step; and the cavity pressurized by the pressurizing pin when the measured required time is equal to or longer than a set time. And a step of cooling the casting mold in the vicinity of the pressure casting method. 2. The solidification state of the filled molten metal is detected from the repulsive force received by the pressure pin by advancing the pressure pin at a slow speed at the stage where the molten metal filled in the cavity of the casting mold is solidified. In a pressure casting method, which comprises a pressure timing determining step of determining the timing of pressurizing, and a pressure step of advancing the pressure pin at high speed at the determined pressure timing to perform pressure, The step of measuring the time required from the start of the pressurizing time determination step to the end of the pressurizing step, and changing the degree of cooling according to the length of the measured time required, And a step of cooling the casting mold in the vicinity of the cavity to be pressurized.