JP3498151B2 - Measuring device for molten metal characteristics in die casting - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molten metal characteristic measuring device for determining the cause of a die opening phenomenon that occurs during casting in die casting.

[0002]

2. Description of the Related Art In die casting, a die opening phenomenon of the die occurs due to an expanding force that expands when a molten metal poured into a cavity is solidified. FIG. 9 shows the relationship between the cavity pressure and the mold opening in casting the parts A, B, and C. For the part A, the mold clamping force was 9.42 ton, the projected area was 498 cm ² , and the cavity pressure was 18.9 kg /
cm ² and the mold clamping force for part B is 9.42 t
on, projected area 572 cm ² , cavity pressure 1
Was 6.46kg / cm ^2, is with the mold clamping force In the part C 8.635ton, projected area 704cm ^2, cavity pressure is 12.26kg / cm ^2.

Conventionally, in order to determine the mold clamping force required to prevent this mold opening, the mold is referred to with reference to documents such as the metal manual shown in FIG. 10 (P574 10, 3, 2 and volume change during solidification). The tightening force was decided. However, since various conditions such as the shape and size of the product are different, it is still impossible to obtain the mold clamping effect without mold opening.

The materials disclosed in documents such as the Metallurgical Handbook shown in FIG. 10 compare the expansion amounts of spheroidal graphite cast iron and flake graphite cast iron (C 3.5%, Si 2.8%, casting temperature 130).
0 ° C), b is the expansion curve of spheroidal graphite cast iron during the solidification process, b is the thermal analysis curve of spheroidal graphite cast iron (change in melt temperature), and c is the flake graphite cast iron during the solidification process. 2 is an expansion curve, and d is a thermal analysis curve (change in melt temperature) of flake graphite cast iron.

Further, the mold material in the current mold casting is generally made of chromium copper alloy for the purpose of rapid cooling, but the mold clamping force is set to be weak in terms of material hardness. Are performing casting work.

[0006]

As described above, the die opening of the die occurs due to the expansion phenomenon when the primary crystal of the product in the cavity occurs, and a part of the molten metal in the cavity enters into the gap to cause burrs. As a result, there is a problem that the product is integrated with the product, and therefore, such a product has a problem that the quality of the product is deteriorated due to a defect in the material accuracy and a decrease in the solidification action due to the mold opening.

In order to solve such a problem, the drive source such as a cylinder device for increasing the mold clamping force may be replaced with a high pressure drive source. However, if a drive source with an excessively high pressure is provided, as described above. , The mold is crushed or deformed because the mold is made of copper alloy,
In addition to the above problems, it is necessary to give rigidity to the die base and tie bars around the mold so that the high pressure can be avoided, resulting in expensive equipment.

The present invention solves the above problems, and an object of the present invention is to provide a molten metal for die casting that can obtain an optimum mold clamping force that matches the manufacturing conditions of each product. It is to provide a characteristic measuring device.

[0009]

In order to solve the above-mentioned problems, a molten metal characteristic measuring device in die casting according to the invention of claim 1 is slidably inserted into an open portion of a casting die and predetermined. A piston member that forms a cavity having a capacity of, a cylinder device that moves the piston member, a specified pressure holding unit that holds the cylinder pressure of the cylinder device at a specified pressure, a displacement measurement unit that reads the movement of the piston member, and a cylinder. It is equipped with a pressure gauge that reads changes in the cylinder pressure of the device, and is fixed to the tip of the piston rod of the cylinder device.
Attach the magnet to the pressure receiving member
It is characterized in that the piston member is adsorbed and held on the shaft.

[0010]

In order to achieve the above object, the claims
According to a second aspect of the present invention, there is provided a molten metal characteristic measuring device in die casting according to the first aspect, wherein the prescribed pressure holding means is fixed to the pressure receiving member and the head side end portion of the cylinder device. And a pressure setting holding bolt for adjusting and setting the maximum separation distance of the pressure receiving member from the holding member.

Further, in order to achieve the above-mentioned object, a claim
According to a third aspect of the present invention, there is provided a molten metal characteristic measuring device in a die casting according to claim 1 or 2, wherein the displacement measuring means is a member for measuring an intermediate portion of a piston rod of a cylinder device. Is mounted so that it can be moved and adjusted, and a displacement measuring dial gauge is mounted on the fixed side member, and the head portion of the displacement measuring dial gauge is brought into contact with the measuring member.

[0013]

According to the present invention, the cylinder pressure is maintained at the specified pressure by the specified pressure holding means, the molten metal is poured into the casting mold to fill the cavity with the molten metal, and the cylinder device is operated. When a constant cylinder pressure of the molten metal in the cavity is applied by projecting the piston member at a specified pressure, the molten metal in the cavity expands (primary crystal state) when solidification starts, and the pressure in the cavity changes.
The pressure change is read by the pressure gauge to measure the cavity pressure.

Therefore, the mold clamping force (cavity pressure × projection area) required can be set by adapting this cavity pressure to a fixed machine, and if a mold clamping force greater than this set value is used, the mold that has been a problem until now has been encountered. The opening phenomenon can be prevented.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a molten metal characteristic measuring device in die casting according to the present invention, and FIG. 2 is a partial sectional view and broken side view of the molten metal characteristic measuring device.

The casting mold 1 used in the apparatus for measuring molten metal characteristics in the mold casting according to the present invention has a cylindrical shape, and the rear end of the cylindrical portion 1a made of Fe material is closed by the end face member 1b made of Fe material. The front surface thereof is opened, and a piston member 2 made of an Fe material is slidably inserted into the released portion to form a cavity 3 having a cavity diameter D. Further, a rapid cooling member 4 made of a Cu material is mounted on the upper part of the casting mold 1, and the rapid cooling member 4 is poured on the upper part of the cylindrical portion 1a on which the rapid cooling member 4 is stacked. A sprue 5 and an exhaust port 6 are formed. The point P is a thermal analysis T.I. C, and point Q is the piston temperature measurement T. It is C.

The casting mold 1 constructed as described above is fixedly mounted on the base 20, which is a stationary member, via the support member 21. A molten metal characteristic measuring device A is fixed to the base 20.

This molten metal characteristic measuring device A is equipped with a cylinder device 7 which is installed adjacent to the front of the casting mold 1. The cylinder device 7 is closed on the head side and has a rod through hole 8 on the rod side. A piston 10 is slidably fitted into the cylinder 9 via an O-ring 10A, and a piston rod 11 connected to the piston 10 has a rod through hole 8 Is slidably and liquid-tightly penetrated to project outward, and a pressure receiving member 12 is fixed to the tip end portion of the piston rod 11.

The front surface portion 12a of the pressure receiving member 12
A magnet 13 is fixedly attached to this magnet 1.
The piston member 2 is adsorbed and held by 3. The attraction and holding of the piston member 2 by the magnet 13
This is to allow the piston member 2 to respond to the fine movement of the piston member 2 at the time of measurement for changing the cavity 3. Further, screw holes 16 for bolts are formed on the left and right sides of the pressure receiving member 12 with the piston rod 11 interposed therebetween.

A holding member 14 is fixed to the end of the cylinder body 9 of the cylinder device 7 on the head side.
4, bolt insertion holes 15 are formed on both sides of the cylindrical body 9 and pressure setting holding bolts 17 are inserted into the bolt insertion holes 15. The tip side of these pressure setting holding bolts 17 A screw portion 17a is screwed into the screw hole 16 for the bolt, and these constitute a specified pressure holding means.

Further, a measuring member 18 is attached to the intermediate portion of the piston rod 11 of the cylinder device 7 by a fixing screw 19 so as to be movable and adjustable. A displacement measuring dial gauge 22a is mounted on the base 20, and a head portion 22b of the displacement measuring dial gauge 22 is mounted.
Is in contact with the measuring member 18 and constitutes displacement measuring means.

Further, a pressure fluid inlet / outlet port 23 is provided on the head side of the cylindrical body 9 of the cylinder device 7, and this inlet / outlet port 23 also serves as a pressure detecting portion of a pressure gauge (not shown).

Next, the measurement of the molten metal characteristics in the die casting by the measuring device constructed as described above will be explained.

The pressure setting holding bolt 17 is moved and adjusted, that is, the pressure setting holding bolt 17 is rotated so that the screw portion 17a on the tip side of the pressure setting holding bolt 17 and the screw hole 16 for the bolt are screw-fed. By changing the length L between the holding member 14 and the pressure receiving member 12, the cylinder pressure is held at a specified pressure (65 kg / cm ² ). And the cavity diameter D is 40φ, 50φ, 60
The set pressure (cylinder pressure) for φ is shown in FIG. 3 and is as shown in [Table 1].

[0025]

[Table 1]

FIG. 3 shows the correlation between the projected area and the expansion output, where the vertical axis is the mold clamping pressure and the horizontal axis is the projected area. The cavity diameter D of the casting mold 1 used for this measurement is 50φ, and its imaging area is 19.625 cm ²
And the cylinder diameter is 40φ.

Then, a molten metal of about 1400 ° C. is poured from the pouring port 5 of the casting mold 1 to fill the cavity 3 with the molten metal. Next, the cylinder device 7 that is the drive source is simultaneously operated to project the piston rod 11, and the pressure receiving member 12 integrated with the piston rod 11 is projected at a specified pressure.

Then, when the molten metal is filled in the cavity 3 and a certain cylinder pressure is applied to the molten metal, the molten metal in the cavity 3 expands with the start of solidification (primary crystal state).
Then, the pressure in the cavity 3 changes. Therefore, this pressure is applied to the pressure receiving member 1 via the piston member 2.
2, the pressure change is read by the pressure gauge 22a, and this becomes the cavity pressure. Cavity diameter D is 5
FIG. 4 shows changes in the molten metal temperature + expansion force and cavity pressure in the case of 0φ.

With the above procedure, the cavity pressure which has not been clarified up to now is set to 5
The test results obtained by changing to 40φ and 60φ in addition to 0φ are shown in FIGS. 5, 6, 7, and 8, and the results shown in [Table 2] are obtained.

[0030]

[Table 2]

In FIGS. 5 and 6, the cavity diameter D is 50φ,
FIG. 7 shows the change of the molten metal temperature + expansion force and the cavity pressure in the case of 60φ, and FIG. 7 shows the correlation between the piston tightening pressure and the expansion force (quantity) displacement amount. It is the tightening pressure, and the horizontal axis is the piston displacement amount. Further, in FIG. 8, the cavity diameter D is 40φ, 50φ,
The change in the cavity pressure in the case of 60φ is shown. From this result, it is clarified that the cavity pressure does not change significantly even if the cavity diameter D, that is, the projected area changes.

Therefore, the mold clamping force (cavity pressure × projected area) required when this cavity pressure is adapted to a fixed machine can be set as shown in [Table 3]. If a mold clamping force above this set value is used, this It is possible to prevent the mold opening phenomenon shown in FIG.

[0033]

[Table 3]

[0034]

As described in detail above, the apparatus for measuring molten metal characteristics in die casting according to the invention of claim 1 has a cavity of a predetermined capacity slidably fitted in the open portion of the casting die. A piston member to be formed, a cylinder device for moving the piston member, a specified pressure holding means for holding the cylinder pressure of the cylinder device at a specified pressure, a displacement measuring means for reading the movement of the piston member, and a cylinder device for the cylinder device. By providing a pressure gauge for reading a change in cylinder pressure, the cylinder pressure is held at the specified pressure by the specified pressure holding means, the molten metal is poured into the casting mold to fill the cavity with the molten metal, and the cylinder device is provided. When the cylinder pressure of the molten metal in the cavity is applied by causing the piston member to project at a specified pressure, the molten metal in the cavity solidifies. The pressure in the cavity and inflated (primary crystal state) with the beginning changed. The pressure change is read by the pressure gauge to measure the cavity pressure.

Therefore, the mold clamping force (cavity pressure × projection area) required can be set by adapting this cavity pressure to a fixed machine, and if a mold clamping force of this set value or more is used, the mold that has been a problem until now has been encountered. The opening phenomenon can be prevented.

The molten metal characteristic measuring device in die casting according to the invention of claim 2 is the molten metal characteristic measuring device in die casting according to claim 1, wherein a magnet is fixed to the pressure receiving member, and the magnet is fixed to the magnet. By adsorbing and holding the piston member, not only the same effect as the molten metal characteristic measuring device in the die casting according to the invention described in claim 1 can be obtained, but also the pressure receiving member adsorbs the piston member through a magnet. The piston member, which changes the cavity for holding, also responds to fine movements during measurement.

The molten metal characteristic measuring device in die casting according to the invention of claim 3 is the molten metal characteristic measuring device in die casting according to claim 1 or 2, wherein the specified pressure holding means is provided in the cylinder. A pressure receiving member fixed to a piston rod of the device, a holding member fixed to a head side end of the cylinder device, and a pressure setting holding bolt for adjusting and setting a maximum separation distance of the pressure receiving member from the holding member. Therefore, not only can the same effect as the molten metal characteristic measuring device in the die casting according to the invention described in claim 1 can be obtained, but the maximum of the pressure receiving member with respect to the holding member by adjusting the pressure setting holding bolt can be obtained. The separation distance can be adjusted and set, and the cylinder pressure can be reliably maintained at the specified pressure, which can contribute to the cavity pressure measurement.

The molten metal characteristic measuring device in die casting according to the invention of claim 4 is the molten metal characteristic measuring device in die casting according to claim 1, 2 or 3, wherein the displacement measuring means is used. , A measuring member is movably attached to an intermediate portion of the piston rod of the cylinder device, a displacement measuring dial gauge is attached to a fixed side member, and a head portion of the displacement measuring dial gauge is brought into contact with the measuring member. Since it is configured as described above, not only can the same effect as the molten metal characteristic measuring device in the die casting according to the invention described in claim 1 can be obtained, but also the displacement of the piston member can be reliably measured and the cavity pressure can be measured. .

[Brief description of drawings]

FIG. 1 is a plan view of a molten metal characteristic measuring device in die casting according to the present invention.

FIG. 2 is a partial cross-sectional view and a broken side view of the same molten metal characteristic measuring device.

FIG. 3 is a diagram showing a correlation between projected area and expansion output.

FIG. 4 is a diagram showing a relationship between changes in molten metal temperature + expansion force and cavity pressure when the cavity diameter D is 50φ.

FIG. 5 is a diagram showing the relationship between changes in melt temperature + expansion force and cavity pressure when the cavity diameter D is 40φ.

FIG. 6 is a diagram showing the relationship between changes in molten metal temperature + expansion force and cavity pressure when the cavity diameter D is 60φ.

FIG. 7 is a diagram showing a correlation between piston tightening pressure and expansion force (quantity) displacement.

FIG. 8 is a diagram showing changes in cavity pressure when the cavity diameter D is 50φ, 40φ, and 60φ.

FIG. 9 is a diagram showing the relationship between cavity pressure and mold opening.

FIG. 10 is a comparative diagram of expansion amounts of spheroidal graphite cast iron and flake graphite cast iron.

[Explanation of symbols]

1 casting mold 2 Piston member 3 cavities 7 Cylinder device 12 Pressure receiving member 14 Holding member 17 Pressure setting holding bolt (specified pressure holding means) 18 Measuring member (measuring means) 21 Displacement measuring dial gauge 21 (measuring means)

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Claims (3)

(57) [Claims] 1. A piston member slidably fitted into an open portion of a casting mold to form a cavity having a predetermined volume, a cylinder device for moving the piston member, and a cylinder pressure of the cylinder device. In a molten metal characteristic measuring device in a die casting machine , which comprises a specified pressure holding means for holding the pressure, a displacement measuring means for reading the movement of the piston member, and a pressure gauge for reading the cylinder pressure change of the cylinder device.
There is secured to the distal end of the piston rod of the cylinder device
A magnet is fixed to the pressure receiving member, and the piston member is adsorbed and held by this magnet.
An apparatus for measuring molten metal characteristics in a die casting machine, characterized by: 2. The specified pressure holding means,The pressure receiving member, Holding member fixed to the head side end of the cylinder device
When, Adjust the maximum separation distance of the pressure receiving member from the holding member.
It consisted of a pressure setting holding bolt for adjusting and settingClaim 1
DescribedMolten metal characteristic measuring device in mold casting equipment. 3. A displacement measuring dial gauge is attached to a fixed side member so that the displacement measuring means can move and adjust an intermediate portion measuring member of a piston rod of the cylinder device, and a head portion of the displacement measuring dial gauge. The molten metal characteristic measuring device in the mold casting device according to claim 1 or 2 , wherein the measuring member is brought into contact with the measuring member.