JPS6119336B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a molten metal forging apparatus, in particular, a mold is constructed from an upper mold and a lower mold that are separably coupled to each other, and a cavity is formed between the opposing surfaces of the upper and lower molds, The present invention relates to a molten metal forging device in which a plunger for filling and pressurizing molten metal toward the cavity is slid onto a plunger sleeve provided in the lower mold.

Conventionally, in such molten metal forging equipment, the plunger sleeve undergoes large thermal expansion due to the heat of the molten metal stored in the cavity, but the amount of heat received from the molten metal is suppressed by the plunger tip provided at the tip of the plunger. Due to the difference in thermal expansion between the plunger sleeve and the plunger, a gap may be created between the two, and the molten metal may flow deeply into the gap, causing a galling phenomenon. etc. had to be replaced, resulting in a shortened lifespan. Therefore, cooling the plunger sleeve in particular has been considered as a countermeasure to this problem. However, although such cooling is effective against the galling phenomenon, the molten metal inside the plunger sleeve, especially the molten metal in the portion that is in contact with the inner peripheral surface of the sleeve, is cooled and solidified, and this solidified portion However, when it is press-fitted into the product flesh, faults occur within the product and the product strength decreases.

An object of the present invention is to provide a molten metal forging device with a simple structure that can eliminate all of the conventional drawbacks. The plunger sleeve includes a hot water storage cylinder having a hot water storage part that directly communicates with the cavity and into which the plunger tip can go in and out, and a lower end of the hot water storage cylinder. and a sleeve body which is integrally connected with a heat insulating material in between, the hot water storage cylinder includes a heater for heating the hot water storage part, and the sleeve body includes a plunger body of the sleeve body. Cooling water passages are provided for cooling the sliding parts.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. In FIGS. 1 and 2, a mold 1
The upper mold 2 and the lower mold 3 are separably coupled together, and the lower mold 3 is composed of an upper half 4 and a lower half 5 separably coupled. A cavity 6 is formed in the upper mold 2 facing the upper mold 3 side, and a plunger sleeve 7 is provided in the lower mold 3 and directly communicates with the cavity 6. A plunger 8 is slidably connected to the plunger sleeve 7. be done.

The upper mold 2 has a knockout pin 1 that also serves as the core.
0 is provided so as to be slidable up and down in a state of being inserted into the cavity 6.

The plunger sleeve 7 has a hot water storage cylinder 11 held in the upper half 4 of the lower mold 3 and a sleeve main body 12 held in the lower half 5.
are concentrically connected by the integration of The hot water storage cylinder 11 is formed in a tapered shape so as to gradually increase in diameter toward the cavity 6, and is provided with a hot water storage portion 9 that directly communicates with the cavity 6 on its inner surface. A flange 13 is integrally provided. On the other hand, in the upper half 4 of the lower mold 3,
A through hole 14 having a slightly larger diameter than the cavity 6 is bored, and a large diameter portion 16 enlarged via a stepped portion 15 is provided in a portion of the through hole 14 near the lower half 5. The hot water storage cylinder 11 has a large diameter end surface 11a flush with the end surface 4a of the upper mold 2 side of the upper half 4, and a flange 13 is fitted into the large diameter portion 16 to form a through hole 14.
inserted into. In this inserted state, the end surface 13a of the flange 13 is flush with the end surface 4b of the upper half 4 on the lower half 5 side. Further, an annular groove 17 is bored in the end surface 13a of the flange 13.

When the hot water storage cylinder 11 is inserted into the through hole 14 of the upper half 4, an annular gap 18 is defined between the outer surface of the hot water storage cylinder 11 and the inner surface of the through hole 14. An electric heater 19 serving as a heating means is wound around the outer surface of the hot water storage cylinder 11 facing this gap 18 .
The electric heater 19 heats the hot water storage section 9 at a temperature of, for example, 300~
It has a heating capacity of about 400℃.

The sleeve body 12 of the plunger sleeve 7 is
It is formed into a cylindrical shape with a flange 20 corresponding to the flange 13 of the hot water storage cylinder 11 at one end. On the other hand, the lower half 5 of the upper mold 3 has a through hole 1 in the upper half 4.
A through hole 21 having a diameter smaller than 4 is concentrically drilled, and a large diameter portion 23 enlarged via a step portion 22 is provided in a portion of the through hole 21 closer to the upper half 4. The sleeve body 12 is inserted into the through hole 21 by fitting the flange 20 into the large diameter portion 23, and in this inserted state, the end surface 20a of the flange 20 is flush with the end surface 5a on the upper half 4 side of the lower half 5. The other end of the sleeve body 12 projects downward from the lower half 5.
Further, an annular groove 24 corresponding to the groove 17 of the flange 13 is bored in the end surface 20a of the flange 20.

A cooling water passage 25 is spirally provided in the sleeve body 12 over almost its entire length, and the cooling water passage 25 includes a sliding portion of the sleeve body 12 with a plunger body 29, which will be described later, for example.
Cooling water that can be maintained at about 170-200°C is supplied.

The hot water storage cylinder 11 and the sleeve main body 12 have an end surface 13a of the flange 13 and an end surface 20a of the flange 20 when the upper half 4 and the lower half 5 are combined to form the upper mold 3. are brought into close contact and integrated. Moreover, when integrating, both flanges 1
The annular space defined by the grooves 17 and 24 of 3 and 20 is filled with a heat insulating material 26, and the heat insulating material 26 functions to prevent heat transfer between the hot water storage cylinder 11 and the sleeve body 12 as much as possible. By integrating the hot water storage cylinder 11 and the sleeve main body 12, the hot water storage portion 9 and the sliding hole 27 are formed concentrically in the plunger sleeve 7.

The plunger 8 includes a cylindrical plunger main body 29 integrally provided with a protrusion 28 at the tip thereof, and
It consists of a bottomed cylindrical plunger tip 30 that is replaceably screwed onto the plunger tip 30. The outer diameters of the plunger body 29 and the plunger tip 30 are selected so that they slide into the sliding hole 27 of the plunger sleeve 7. Further, the plunger tip 30 is made of a material with low thermal conductivity such as ceramic, and prevents as much as possible the high heat from the molten metal stored in the hot water storage section 9 from being transmitted to the plunger body 29. Functions to prevent burn-in.

The plunger body 29 has a plunger tip 3.
A cylindrical rod 32 that communicates with the cooling hole 31 and protrudes outward from the other end of the sleeve body 12 of the plunger sleeve 7 is provided with a cooling hole 31 that opens on the opposite side from the plunger body. 29 and is connected by screwing. Rod 32 has
Cooling water supply pipe 3 with one end facing cooling hole 31
3 is inserted through the rod 32, thereby forming an annular cooling water discharge passage 34 between the inner surface of the rod 32 and the outer surface of the cooling water supply pipe 33. Therefore, the cooling water supplied from the cooling water supply pipe 33 cools the plunger body 29 through the cooling hole 31 and is then discharged through the cooling water discharge path 34.

Next, to explain the operation of this embodiment, in molten metal forging, molten metal such as aluminum alloy as a material is poured into the molten metal storage part 9, and the electric heater 19
With electric power energized and cooling water being supplied to the cooling water passage 25 and the cooling water supply pipe 33, the rod 32 is pressed and driven by a driving means such as a hydraulic cylinder (not shown). As a result, the plunger 8 protrudes into the hot water storage section 9 as shown by the chain line, and the molten metal removed by the protrusion of the plunger 8 fills the cavity 6 and is pressurized, and this pressurized state is maintained for a certain period of time. .

In this process, the sleeve body 12 of the plunger sleeve 7 and the plunger body 29 of the plunger 8 are cooled to about 170 to 200°C by the cooling water. Also plunger sleeve 7
The hot water storage cylinder 11 has a temperature of 300 to 400 depending on the electric heater 19.
It is heated to about ℃. Moreover, the sleeve body 1
Since a heat insulating material 26 is interposed between the hot water tank 2 and the hot water storage cylinder 11, heat transfer therebetween is prevented as much as possible. Therefore, the temperature of the hot water storage cylinder 11 is between 300 and 400.
The temperature of the sleeve body 12 is maintained at about ℃.
The temperature is maintained at around 170-200℃.

By heating the hot water storage cylinder 11 in this manner, the molten metal in the portion in contact with the inner surface of the hot water storage portion 9 is prevented from being cooled and solidified due to contact with the inner surface. Furthermore, even if solidification occurs, the hot water storage cylinder 11 is formed to gradually become larger in diameter toward the cavity 6, and the plunger 8 moves on the central axis of the hot water storage cylinder 11, so the plunger The molten metal in the center of the hot water storage section 9 is pressed toward the cavity 6 and filled. Therefore, the solidified portion generated near the inner surface of the hot water storage portion 9 is prevented from entering the cavity 6 as much as possible, and as a result, the solidified portion is prevented from being press-fitted into the product flesh part and causing a fault, thereby improving the product strength. will improve.

On the other hand, due to the cooling effect of the cooling water on the sleeve body 12 and the plunger 8, and the heat shielding effect of the heat insulating material 26 and the plunger tip 30, the temperatures of the two are almost the same, so there is no difference in the amount of thermal expansion between the two. There are very few, and as a result,
It is possible to prevent the creation of a gap between the sleeve body 12 and the plunger body 29 through which molten metal can flow, thereby preventing galling from occurring and extending the life of the plunger sleeve 7 and the plunger 8. becomes possible.

After filling the cavity 6 with molten metal for a certain period of time and applying pressure, the upper mold 2 and the lower mold 3 are separated, and the product material solidified in the cavity 6 is pushed out by the knockout pin 10. Then, it is taken out from the cavity 6. Thereafter, the product material is subjected to finishing processing.

In other embodiments of the invention, the cooling means for the plunger 8 may be omitted.

As described above, according to the present invention, the mold 1 is constituted by the upper mold 2 and the lower mold 3 that are separably coupled to each other, and the cavity 6 is formed between the opposing surfaces of the upper and lower molds 2 and 3. , a molten metal forging device in which a plunger 8 for filling and pressurizing the molten metal toward the cavity 6 is slid onto a plunger sleeve 7 provided in the lower mold 3, the plunger 8 is attached to the upper end of the plunger body 29. Plunger tip 30 made of low thermal conductivity material such as ceramic
The plunger sleeve 7 includes a hot water storage cylinder 11 having a hot water storage part 9 that directly communicates with the cavity 6 and into which the plunger tip 30 can go in and out, and a heat insulating material 26 under the hot water storage cylinder 11. The sleeve main body 12 is connected integrally with the
The hot water storage cylinder 11 includes a heater 19 for heating the hot water storage portion 9, and the sleeve body 12 includes a heater 19 for cooling the sliding portion of the sleeve body 12 with the plunger body 29. Since cooling water passages 25 are provided for the hot water storage portion 9, the hot water storage cylinder 11 of the plunger sleeve 7
Even if it is strongly heated by the molten metal inside or the heater 19, the heat insulating material 26 prevents the heat from moving toward the sleeve body 12.
and the sleeve body 12
The plunger body 29 can be efficiently cooled by the cooling water flowing through the cooling water passage 25, and the amount of heat received from the molten metal can be suppressed by the plunger tip 30, and the sleeve body 12. By reducing the temperature difference between the two
It is possible to prevent the formation of a gap between 9 and 12 through which molten metal can flow due to the difference in thermal expansion, and the plunger body 29
It is possible to prevent galling between the sleeve body 12 and the sleeve body 12, thereby contributing to improving their durability.
Furthermore, the hot water storage section 9 is sufficiently heated by the heater 19, and the heat is prevented from escaping to the cooling water passage 25 side of the sleeve body 12 by the heat insulating material 26, so that the molten metal in the hot water storage section 9 is A solidified portion is hard to form inside the melt, and the hot water storage portion 9 is directly connected to the cavity 6, and when the plunger 8 is pushed in, the molten metal in the hot water storage portion 9 can be immediately pumped into the cavity 6 without cooling. Hot water storage section 9
The molten metal inside can be quickly and accurately filled and pressurized into the cavity 6 without involving the solidified portion,
Therefore, there is no possibility that the solidified portion is press-fitted into the meat part of the product and a fault occurs, which can greatly contribute to improving the strength of the product.

Furthermore, since the filling and pressurizing of the molten metal into the cavity 6 can be performed continuously by a plunger device consisting of only one pair of plunger 8 and plunger sleeve 7, the structure of the molten metal forging device is simple and costs can be reduced. Not only can it contribute to this, but it can also increase productivity.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is an overall vertical sectional view, and FIG. 2 is an end view taken along the line -- in FIG. 1. 1... Mold, 2... Upper mold, 3... Lower mold, 6...
Cavity, 7... Plunger sleeve, 8...
Plunger, 9...Hot water storage section, 11...Hot water storage cylinder, 1
2... Sleeve body, 19... Heater, 25...
Cooling water passage, 26...insulation material, 29...plunger body, 30...plunger tip.

Claims (1)

[Claims] 1 A mold 1 is constituted by an upper mold 2 and a lower mold 3 that are separably coupled to each other, and a cavity 6 is formed between the opposing surfaces of the upper and lower molds 2 and 3, and a plunger provided in the lower mold 3 is formed. In a molten metal forging device in which a plunger 8 for filling and pressurizing molten metal toward the cavity 6 is slid onto the sleeve 7, the plunger 8 is made of a low thermal conductive material such as ceramic at the upper end of the plunger body 29. The plunger sleeve 7 has a hot water storage cylinder 11 having a hot water storage part 9 that directly communicates with the cavity 6 and into which the plunger tip 30 can go in and out. The sleeve main body 12 is connected integrally with a heat insulating material 26 in between. 12. A molten metal forging apparatus characterized in that cooling water passages 25 for cooling the sliding portions with the plunger body 29 are provided respectively.