JPS5921261B2 - Casting equipment with automatic hot water supply system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a casting device equipped with an automatic hot water supply device used in a die casting machine.

In conventional die casting machines, the most suitable casting conditions for die casting, such as casting speed, casting pressure, high speed casting start position, and deceleration position, can be set in advance. was configured so that this setting condition could be fixed.

In order to stabilize the quality of die-cast products, it is a prerequisite to accurately reproduce the casting conditions set in this way, but this is not done in practice.

The reason for this is that the amount of molten metal or molten alloy (hereinafter simply referred to as molten metal) supplied to the die casting machine varies and is not constant.

Fig. 1 A, B and Fig. 2 A, B explain the situation during this period. In each figure, 1 indicates a fixed plate, 2 indicates a movable plate, and each has a fixed mold 3 and a movable plate. A mold 4 is attached.

A mold cavity 5 is formed in the direction in which the two molds 3° 4 abut against each other.

Reference numeral 6 indicates a sleeve, and a molten metal supply port γ is formed near its outer end, and a tip 10 fixed to the tip of a hydraulic cylinder 80 and rod 9 is slidably fitted inside. .

In the middle of the rod 9 is a lever 11 for horizontally positioning the high speed casting start position.
A limit switch 12 for regulating the high speed casting start position is arranged on the side thereof.

In a die casting machine having the above-described known structure, if the amount of molten metal supplied into the sleeve 6 is less than the specified value, as shown in FIG. To start casting, air bubbles are drawn into the die-cast product, resulting in a defective product.

In addition, when the amount of molten metal is larger than the specified value, as shown in Fig. 2A, high-speed casting starts with most of the molten metal entering the cavity 5, and the molten metal that has entered the cavity solidifies, making it impossible to obtain a homogeneous die-cast product.

As shown in FIG. 1B and FIG. 2B, the thickness t of the biscuit 13 changes due to variations in the amount of molten metal.
This will lead to changes in filling time, etc., which will impede the quality stability of die-cast products.

FIG. 3 explains a conventional automatic water heater, in which a ladle 16 is attached to the tip of an arm 15 in an inverted dogleg shape extending from a known drive unit 14 consisting of a combination of gears, cylinders, etc. The arm 15 is driven so that the arm 16 moves along a predetermined trajectory 1γ,
The molten metal 19 in the heat retention furnace 18 is pumped up and is supplied into the supply port γ of the sleeve 6.

However, there are variations in the amount of molten metal supplied, resulting in the drawbacks mentioned above.

Naturally, the first thing to do to eliminate these shortcomings is to improve the hot water supply accuracy, but at present it is unavoidable that variations of ±5 factors occur, and if you try to achieve even higher accuracy, the hot water supply cycle will be shortened. It becomes longer and its practicality is significantly reduced.

The present invention has been made in order to eliminate the above-mentioned drawbacks of the conventional method, and provides a casting device equipped with an automatic hot water supply device that can keep one casting condition constant while maintaining the current hot water supply accuracy. It is.

Hereinafter, the present invention will be described in detail together with embodiments shown in the drawings.

FIG. 4 is for explaining one embodiment of the present invention. In this embodiment, the arm 15 to which the arm 16 of the automatic water heater as shown in FIG. It is divided into an extending first arm 15a and a second arm 15b to which a diagonal 16 is attached, and the two arms are rotatably supported by a pin 26, and a protrusion is provided at the base of the second arm 15b. 27, and a load detector 20 such as a load cell, a load sensor, or a compression type load converter is provided on the first arm 15a side, such as a load cell, a load sensor, or a compression type load converter.

29 indicates the second arm 15 when the arm 15 is in operation.
Since b does not rotate counterclockwise in the figure, arm 1
This is a stopper attached to 5a.

A drive device 22 consisting of a servo motor or a pulse motor is attached to the side surface of the casting cylinder 8 via a suitable bracket 21, and a screw shaft 23 is driven forward and backward by this drive device 22. extends parallel to the axis of the cylinder 8.

This screw shaft 23 has a mounting seat 24 that does not rotate.
It is screwed together so that it can move only in the axial direction of the screw @23, and a limit switch 12 is fixed to this mounting seat 24 for regulating the high-speed casting start position, and its contactor is always connected to the detection lever 11. are in sliding contact.

The load detector 20 measures the weight of the molten metal.
However, since the ladle is empty during the return stroke of the hot water supply process, if you can measure the difference, you can determine the weight force of the molten metal.

The load detected by the load detector 20 enters the arithmetic unit 25 as an electrical signal, where it becomes a predetermined electrical output and is sent to the drive device 22.

Here, the arithmetic device 25.1g, the moving device 22, the screw shaft 23, etc. control the position of the limit switch 12 for high-speed injection start command based on the signal from the load detector 20, and perform high-speed injection, which is one of the casting conditions. It can be said to be a casting condition setting device that can set a starting point.

Of course, the device for commanding the high-speed injection starting point is not limited to the limit switch 12, but other known position detection command devices such as a non-contact switch, a magnetic scale, a magnetic head, etc. can also be used.

Further, the injection speed can also be changed by controlling the timing of changing the opening degree of the flow rate regulating valve using a pulse motor or the like as the driving device 22.

The calculation section 25 performs the following calculations.

First, the casting weight W of the target die-cast product and the diameter D of the sleeve of the die-casting machine (see Fig. 5) are input in advance.

1. Since it is generally said that it is best to start high-speed casting when the sleeve 6 is filled with molten metal, let the specific gravity of the molten metal be γ, calculate L from -D2Lr=W, and L=
4W/πD2γ is calculated and the position of the chip 10 is stored.

At this time, the load signal W sent from the load detector 20
When W = Wo + (W + △W) (Wo is the tare weight, △W is the variation in the amount of hot water supplied), the high-speed casting start position is moved △ to fill the sleeve 6 with molten metal. L
is calculated using the following formula.

△L=4ΔW/πD2r=4(W W□-W)/yr
D2r= 4 (W-WO)/yrD 2r -L Tare weight W of ladle 16.

is constant, so if this is also input in advance, an output signal △L corresponding to the change in the hot water supply W detected by the detector will be obtained, which will be amplified and supplied to the drive device 22 to drive the screw shaft. 23 and move the limit switch 12, the high speed casting start position can be adjusted accurately.

Since this embodiment is configured as described above, high-speed casting is always started when the molten metal fills the sleeve, eliminating gas entrainment and molten metal jumping into the cavity, resulting in high-speed casting. A high-quality product can be obtained, and since the high-speed casting section is constant, the filling time is constant, and the quality of the product is stable.

Furthermore, the position of the IJ Mitsutwitch for regulating the high-speed casting start position is automatically adjusted by simply inputting the casting weight and sleeve diameter, making the operation extremely simple.

Of course, the load and the amount of hot water detected by the load detector 20 are applied to a gauge, and the scale of this gauge is read by the operator orally each time, and the operator operates the drive device 22 by operating a lever or the like to perform high-speed casting. It is also possible to adjust the starting position.

In the above example, the high-speed casting start point was explained as the point when the sleeve 6 was filled with molten metal, but this means that after the sleeve 6 was filled with molten metal, the mold cavity If it is determined that it is best when the molten metal enters into the chamber 5, the position of the tip 10 is determined to be slightly smaller than the calculated value.

Ru.

FIG. 6 explains another embodiment of the present invention, and this embodiment employs a structure in which the deceleration start position can also be automatically controlled.

That is, in this embodiment, the rod 9 of the cylinder 8
The rod 9 is formed hollow, and a through hole 9b is bored in the rod 9 near the piston 9a.

A hollow rod 30 whose deceleration position is being adjusted is inserted from the head side of the cylinder 8.

This rod 30 slidably passes through the piston 9a and is inserted into the rod 9, and a through hole 3J)a and a through hole 30b are bored near the piston 9a and halfway inside the rod 9. There is.

35 is a check valve. In addition, the rod 30 and the screw shaft 23
The zero base end is housed in a gear hook 31, and a worm wheel 32 is fixed to the screw shaft 23 in the gear box 31, and a worm wheel 33 rotatably supported on the gear box 31 is screwed to the rod 30. Both worm wheels 32 and 33 are meshed with a worm gear 34 fixed to the output shaft of a drive device 22 such as a pulse motor or a nervo motor attached to the side of the gear hook.

Since this embodiment is configured as described above, during casting, the hydraulic oil on the rod side of the cylinder 8 is supplied to the piston 9.
a into the rod 9 through the through hole 9b, and further into the rod 30 through the through hole 30b.

The hydraulic oil in the rod 30 passes through the check valve 35 in the rod 30 and enters the head side of the cylinder 8 through the through hole 30a.

In this state, the casting operation by the rod 9 progresses, and soon high-speed casting is started by the cooperation of the limit switch 12 and the detection lever 11. The rod 9 moves forward at high speed, and just before the end of high-speed casting, the rod 30 is moved by the piston 9a.
When the through hole 30b is blocked, the hydraulic oil on the rod side cannot communicate with the head side of the cylinder 8, a mechanical brake is applied, and deceleration is started.

Therefore, if the load detection device 20 detects the amount of molten metal, the calculation device 25 calculates it as described above, the result is amplified and supplied to the drive device 22, and the worm gear 34 is rotated. By displacing the position of the limit switch 12 via the screw shaft 23, the cylinder 8
It is also possible to reduce the peak pressure by changing the high-speed casting start position of the cylinder 8 and by moving the rod 30 via the worm wheel 33 to change the deceleration start position of the cylinder 8.

Here, the arithmetic unit 25. Drive device 22° worm gear 34. Worm foil 33. The rod 30 and the like can be said to be a casting condition setting device that can control the start point of deceleration of the injection speed, which is one of the casting conditions, based on the signal from the load detector 20.

Of course, the one shown in FIG. 6 also includes a casting condition setting device that can control the high-speed injection starting point based on the signal from the load detector 20.

If the amount of hot water supplied changes, the solidification time of the molten metal will also change, but the mold clamping curing time can be adjusted accordingly, and if the amount of hot water supplied is abnormally high or low, this can be detected and an alarm signal sent. It is also possible to automatically stop the operation of the machine or change the cycle of the machine.

In addition to controlling the casting conditions, we also control the temperature of the mold, sleeve, plunge, tip, etc.

There is also control of the casting pressure and the timing of evacuation during vacuum die casting, but automatic control is possible by inputting set values of this information into the arithmetic unit.

As is clear from the above description, according to the present invention, high-speed casting is performed at a desired point, such as when the sleeve is filled with molten metal, so that gas entrainment and molten metal into the cavity are prevented. A high-quality product is obtained with no splashing, and since the high-speed casting section is constant, the filling time is constant, the quality of the product is stable, and the high-speed casting start position and force can be adjusted dynamically, making operation extremely easy. becomes.

In addition, it is possible to automatically adjust the deceleration position of the injection operation and mold clamping curing time according to the amount of hot water supplied, issue an alarm when there is an abnormality in the amount of hot water supplied, and automatically adjust operations such as stopping the equipment. .

[Brief explanation of drawings]

Figures 1A and B and Figures 2A and B are respectively explanatory diagrams of situations in which problems occur due to differences in the amount of hot water supplied; Figure 3 is an explanatory diagram of an automatic hot water supply device; and Figure 4 is an embodiment of the present invention. side view,
5A and 5B are explanatory diagrams of calculation elements, and FIG. 6 is an explanatory diagram of another embodiment of the present invention. 3...Fixed mold, 4...Movable mold, 5
...Cavity, 6...Sleeve, 1
0... Chip, 12... Limit switch, 14.22... Drive device, 15...
...Arm, 15a...First arm, 15b
...Second arm, 16...Hishiyaku, 20...Load detection device, 25...Arithmetic device, 30...Rod , 32.33...
... Worm foil, 34... Worm gear

Claims (1)

[Scope of Claims] 1. The arm connecting the drive part of the automatic water heater and the ladle is divided into a first arm extending from the drive part and a second arm to which the ladle is attached. and an automatic device characterized in that the second arm is rotatably connected with a pin, and a load detector whose displacement changes depending on a change in the weight of the molten metal in the cup is attached to the connecting portion of the first and second arms. Casting equipment equipped with hot water supply equipment. 2 The arm that connects the drive part of the automatic water heater and the ladle is divided into a first arm extending from the drive part and a second arm to which the ladle is attached, and these first and second arms are separated. The first and second arms are rotatably connected by a bottle, and a load detector whose displacement changes depending on changes in the weight of the molten metal in the bottle is attached to the connection part of the first and second arms, and the casting conditions are set based on the signal from this load detector. 1. A casting device equipped with an automatic hot water supply device, characterized in that it is equipped with a casting condition setting device that allows the casting conditions to be set. 3. Claim 2, characterized in that the casting condition setting device includes a device capable of controlling a high-speed injection starting point.
A casting device equipped with the automatic hot water supply device described in 1. 4. A casting device equipped with an automatic hot water supply device according to claim 2, characterized in that the casting condition setting device includes a device capable of controlling the start point of deceleration of the injection speed. 5. An automatic hot water supply device according to claim 2, characterized in that the casting condition setting device includes a device configured to automatically control a high-speed injection start point and a deceleration start point of the injection speed. Equipped with casting equipment.