JPS60141360A - Casting device - Google Patents

Abstract

PURPOSE:To improve reproducibility by providing a hermetic chamber which contains a melting crucible, casting mold, etc., and can be freely evacuated and pressurized and enabling automatic and simultaneous execution of pressurization of a gas and pouring. CONSTITUTION:A casting device consists of an electrical heating means 2, a longitudinally long melting crucible 3 installed therein, a casting mold 4 provided below said crucible in connection thereto, a sprue communicating the lower part of the pouring cup 311 of the crucible 3 and a spray 411 opened to the mold 4 and a hermetic chamber 1 which contg. said means, etc. and can be freely evacuated and pressurized. The inside of the chamber 1 is evacuated and the melt for casting held in the pouring cup 311 by surface tension is forced into the mold 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a casting apparatus suitable for pressure casting using gas.

For example, to cast crown dentures, artificial teeth, etc., centrifugal casting and pressure casting using the lost wax method have been carried out using pleasure metals, non-bragence metals, etc.; In the case of pressurization, a method has been adopted in which the upper part of the socket of the mold is completely covered with a water-containing cap, and after the molten metal is injected, the water in the cap is rapidly vaporized by the heat of the socket, and the vapor pressure is used to pressurize the mold.

As is clear from this method, conventional gas pressure casting is primitive and requires a certain amount of skill and professional judgment on the part of the operator, and the reproducibility is poor1. Problems remain.

In view of these problems, the present invention provides an apparatus that can automatically and synchronously pressurize gas and pour molten metal, thereby performing accurate pressure casting with high reproducibility. In addition, the present invention provides a device that can automatically link the melting and casting of casting materials, and the melting and casting parts are small enough to be placed on a table even when combined. Moreover, it has the feature that it is extremely easy to set and take out the mold.

The device of the invention is also suitable for casting not only the metals or alloys mentioned above, but also vitreous ceramics.

A preferred embodiment of the present invention will be described in more detail below with reference to the drawings; Fig. 1 is a front view showing one embodiment of the present invention, and Fig. 2 is a mold operating section of Fig. 1. It is a longitudinal sectional front view of a state in which the melting crucible and mold inside are raised together with the table and set in the furnace body, and FIG. 3 is a longitudinal sectional front view of the crucible and the mold as separate bodies.

First of all, the first invention is a cylindrical electric heat generating means (2) C, hereinafter simply referred to as heat generating means, which is installed upright in a closed chamber (1) which can freely reduce and increase pressure as shown in FIG. ] and a vertically elongated melting crucible (3
) and a mold (
4), and a sprue (5) that communicates the lower part of the socket (all) of the melting crucible (3) with the sprue (411) of the casting 7M, (4), and the socket (all) If there is no substantial gas pressure difference between the inside of the mold (4) and the inside of the mold (4), the casting melt (6) melted in the socket (all) will enter the sprue (5) due to its surface tension. This is a casting device that can hold water without falling, and the invention shown in FIG. A connected cylindrical sealed chamber (1), a cylindrical resistance heat generating means (2) installed vertically at the lower center of the chamber (1), and a cylindrical resistance heating means (2) surrounding the heat generating means (2). (1) Thermal insulation means (
7), and a gas passage (a) communicating the outlet pipe (8) and the heat generating means (2). A table (2) that can be brought into contact from below, a mold (4) placed on this chieble mold, and a sprue (5) that communicates with the sprue (411) of this mold (4) are connected to the socket (811). The furnace body part [111] includes a vertically elongated melting crucible (3) that is open to the lower part and is connected above the mold (4), and a casting operation part f13 that is connected directly below the furnace body part [111]. The above table (121
The socket (311) of the melting crucible (3) is brought into contact with the heat generating means (
In the effective heating zone (J) of 2), the molds (4) are respectively arranged in the small diameter cylindrical portions (9), and the sockets (811) and the inside of the molds (4) are substantially the same. When there is no gas pressure difference, the casting melt (6) melted in the socket (all) can enter the sprue (5) due to its surface tension and stay there without falling. In the third invention, the bottom part of the furnace body part 111) is connected to the table of the mold operation part 03 (
When the mold is closed and the mold is set in step 1 and pressure cast is performed,
Due to the pressurization, the table (2) also moves to the furnace body (11).
This is a version with additional considerations to prevent it from leaving from 1.
A ring-shaped hollow (14
A cylindrical wall (1-) surrounding the chamber (151) separated by 1 ft is provided at the bottom of the chamber (1), and a vacuum penetrating through this cylindrical wall (151
By fully applying pressure to the pressure outlet pipe (10), the front table (121) can be attracted to the bottom of the chamber (1).

The second and third inventions will be explained in more detail below. 071 in Figure 2
In the case of the figure, the bottom of this cradle (Iη is placed on the table (2) with a flat surface, When pressurizing the mold (4) during casting after reducing the pressure in the mold (4) by making contact with a multi-stage surface that allows a large contact area instead of a flat surface, the positive pressure in the chamber (1) increases the pressure in the mold (4). ) In some cases, it may be desirable to take measures to prevent the gas from being press-fitted into the mold (4) from the bottom. 2) A gas-barrier sealing material made of a heat-resistant material arranged so as to be concentrated around the crucible (3) and the mold (4),
The lower one of the heat insulating means (7) is the heat insulating material (72).
), for example, ceramic fibers are similarly molded into a ring shape using a bonding agent. The heating means (2) is a cylindrical, for example, ceramic resistance heating element, and forms a heating part 12D in which a resistance heating element is built in at the lower part of a cylindrical body (2) which is made by combining left and right halves. Heating Zone (1) [The zone including the central portion in the longitudinal direction of the heat generating portion C1l which exhibits a particularly high value in the heating temperature distribution is called this. ] A socket (311) for the crucible (6) is arranged inside. Inside the upper opening of the cylindrical body (■), a lid a!1 is sealed, which holds a central through hole (191) and a thermoelectric body (to) that detects the temperature inside the heat generating part (211) through the central through hole (191). 191) opens into the chamber lumen above the insulation means (72).

bound by a band (a). Chamber (1)
A lid (to) is fixed to the upper end opening by a set screw (2), and a viewing window hole (148) is provided in the center of this lid (2).
1) is inserted through the window hole (281), and the window edge member (281) holds a glass or other transparent window plate (to) with a set screw (2).
3]) is stopped and is attached by (82). The socket (811) of the crucible (3) has a convergent curved surface with respect to the sprue (5), for example, an elliptical curved surface, a plum curved surface, or a circular arc curved surface. The diameter of the sprue (5) is
If there is no substantial pressure difference between the crucible (3) and the mold (4), the melt (6) in l) will not fall through the sprue (5) and will fall through the sprue (5) due to its surface tension. The dimensions shall be selected such that it can be stored inside the tank. The example in Figure 2 shows a case where the crucible (3) and mold (4) are integrally molded, and the investment (43) is used across both. Those that are separate and connected together will be described later. The outlet pipe (8) is connected to a cylindrical wall (15 is a casing (1), which is connected to a vacuum pump (not shown).
) shows a 'iL-type table [12] with sealing pads attached to the lower end of the footrest (151) and the lower end of the small-diameter cylindrical part (9) of this cylindrical wall αS, respectively. (83
), the ring-shaped space (141
is hermetically sealed, so when the air is evacuated from another outlet pipe (161), the pressure in this space (inside one section) is reduced and the table (2) is moved to the cylinder wall 0.
9 and the leg stand (151). next,
Regarding the mold operation section (13) located directly below the furnace body section 111, this operation section (131 is located on the base of the tabletop shop (
34) and left and right side frames (135), (36)
and this base (34) and both side frames (35).

(36) and an operation opening (37) opened between the two, and an operation opening (37) which is exposed in the operation opening (37) at the lowest position, and a standby for pouring as shown in Fig. 2 at the highest position. Table (I21% mold pedestal 07), mold (4) that reaches the state
and a melting and casting assembly including a crucible (3), and an elevating arm 1 (88) for elevating and lowering these while maintaining a horizontal level.
) and a resilient horizontal holding coil spring (39). On the front of the base (34), there is a power supply 0N10FF switch (40), a raise/lower switch (41), a furnace temperature display section (42), a furnace temperature setting button (411), a temperature hold timer ( 44), pressure timer (45), pressure reduction setting switch (46), furnace pressure setting switch (47), pressure setting switch (4)
day), start button (49), standby button (50),
Operation switches and buttons such as a release button (51) are provided. Note that the lift arm (38) is raised and lowered by an electric lifting mechanism (not shown). In the above, an example was given in which the table (I2) is raised and lowered, but the present invention is not limited to this, and the chamber (1) may be lowered.

This casting! Operate the operation part 0J to move the melted and cast member to the furnace body part fi.
I set it to 1, melted and cast, and took out the loss after casting.
I will be described below.

(-1 Turn on the power switch (4) in the lowered position on the table side in Fig. 1 to start heating the heating means (2) of the furnace body opening υ. (1
41 and raise the table U to the furnace body (company) side using the table lift switch (41), the furnace body til
The interior is automatically preheated to 350°-500'O.

(b) Set the casting temperature using the furnace temperature setting button (48), and then set the temperature hold timer (48) to hold the temperature.
Set in 4). A switch (46) is used to set the pressure in the furnace until the temperature is maintained, and a pressure setting switch (48) is used to set the pressure during pressurization following release of the pressure reduction.

(C) Next, when the standby button (50) is pressed, the table side rises to the furnace body part [11] and the inside of the furnace body part Lllll rises to the set temperature. For example, a lamp (not shown) flashes when the set temperature is reached.

(d) Lower the table (13) using the table lowering switch (41), place the mold (4) and crucible (3), and place the metal (alloy) for melting, glass material in the socket (811) of this crucible (3). Immediately press the start button (4g) after loading the ceramic raw material.As a result, the table rises to the mouth of the furnace body, and the pressure inside the furnace body U is subsequently reduced to the previously set pressure. At the same time, the temperature rises to the set temperature and is held for a set time, and when the holding is finished, the depressurization stops and the pressure is maintained at the previously set pressure and time. After casting is completed, the table (2) lowers with a buzzer sound, and returns to the state where the power switch (4) is turned ON.This pressurized casting is fully automatic. The depressurization and pressurization are done by the outlet pipe (8), and the depressurization and pressurization of the crucible (3) and the mold (4) are done through the entire gas passage (g).
It's true. On the other hand, the ring-shaped space (within 1Φ is a table (
Even when the inside of the mold (4) is pressurized 21' by suctioning and holding the table 0z at the lower end opening of the ring-shaped space 141 while maintaining the reduced pressure independently of the chamber (1) until +21 is lowered. This prevents the table uz from coming off downward. Note that interruption during standby processing and automatic operation is performed using the release button (51). After the table +121 has finished lowering, the mold (4) is disassembled, the product is extracted, and a new mold is set on the crucible mold holder and used for the next operation in the same manner as above. In the above, the casting material used is pleasure metal, non-precious metal, or vitreous ceramic (castable ceramic) in the case of dental crowns, but it can also be applied to pressure casting other than dentistry. is clear.

In the embodiments illustrated in FIGS. 1 and 2, the melting crucible (3) and the mold (4) are integrated, but in FIG. ) shows an example of forming a hot water reservoir. As shown in the figure, a forward expanding opening (82) is provided at the lower end of the sprue (5) of the vertically long cylindrical crucible (3), and the crucible (3) is fitted into the upper end of the mold (4). A cylindrical recess (412) is provided between the recess (412) and the sprue (411), and the forward expanding IM port (32) is provided between the recess (412) and the sprue (411).
The previously reduced openings (4, 18) corresponding to the above were formed, and both openings (3
2).

(412) is located between the sprue (5n) and the sprue (41).
414) is formed to replenish the lack of molten metal in a mass product. FIG. 4 shows another example in which the crucible (3) and mold (4) are separate bodies, similar to the example in FIG. The diameter has been reduced to reduce the heat capacity, and the upper and lower parts (5g) that are connected to this, (54)
The diameter is increased to increase the heat capacity to reduce the leakage of radiant heat inside the furnace to the outside, and to reduce the amount of gas at the point where the radiant heat inside the furnace leaks to the outside, as well as at the connection between the crucible (3) and the mold (4). When pressurized, the investment material in the crucible (3) becomes the poet's (4) sprue (411)
This differs from the previous example in that the connection part (55) of the mold (4) is shaped like a truncated cone to prevent it from entering the mold.

Next, the functions and effects of the first to eighth inventions will be described.

In the first invention, the socket (311) of the melting crucible (3)
) in the socket (81) when there is no substantial gas pressure difference between the socket (311) and the inside of the mold (4).
1) High flowability is maintained while the fluid remains in the chamber (1) and heated, but as soon as pressurization begins in the chamber (1), the sprue (5) and sprue synchronously open. (411) ft.
Then, the molten metal is poured into the mold (4) all at once, and the molten metal is pressed down to the smallest detail by the positive gas pressure from above, making it possible to cast with high dimensional accuracy. Then, the crucible (3) is connected to the heating means (
2) and placing it in the effective heating zone (1) of the heat generating means (2) enables thermally efficient casting at high temperatures, and due to the interaction between the crucible (3) and the mold (4) Casting can be performed with as little heat loss as possible during the falling of the molten material (6). Furthermore, since the pouring is done synchronously with the introduction of gas, highly reproducible casting is guaranteed.

In the second invention, while retaining the above advantages, the furnace body part uD and the mold operating part (131) are vertically connected, and in this mold operating part +131, the mold (4), the crucible (3) After setting, the product is automatically raised to perform casting, and the casting layer is lowered to take out the product and set it again.This makes use of vertical space and saves horizontal space. Efficient pressure casting is possible in a small space.The eighth invention is based on the advantage of the second invention when the inside of the furnace body (1) is changed from under reduced pressure to pressurized VC#. But the ring-shaped space (1
As long as the inside of 41 is depressurized, the table surface will not fall downward and will be held tightly against the bottom surface of the furnace body (1) even by the above-mentioned pressurization. An additional benefit is that the table decoy can be held using the same depressurization method as that of the furnace body part 1.

As a result of the above, the present invention has an excellent effect in that it can eliminate the shortcomings of the known techniques, which were poor reproducibility despite the fact that it required a skilled technician.

[Brief explanation of the drawing]

FIG. 1 is a front view showing one embodiment of the present invention, and FIG. 2 is a front view showing one embodiment of the present invention.
FIG. 3 is a longitudinal sectional front view of the melting crucible and mold in the mold operation section shown in the figure raised together with the table and set in the furnace body, and FIG. 3 shows an embodiment in which the crucible and mold are separate bodies. 4 is a vertical sectional front view of only the essential parts showing another aspect of the crucible and mold shown in FIG. 3; FIG. (Code theory 8A) 1... Sealed chamber, 2... Electric heating means, 8...
・・Melting crucible, 4・m 凰, 5・sprue, 6・・
- Molten material for casting, 7... Insulating means, 8, 16... Outlet pipe for depressurization and pressurization, 9... Small diameter cylindrical part, 10... Gas passage, 11... Furnace body part, 12...Table, 1B.
... Mold operation section, 14... Ring-shaped space, 15...
Cylinder wall, 311...Socket, 411...Sprue,!
...Effective heating zone. - Above - Attorney Patent Attorney (6285) Hidehiko Matsuno Procedure Supplement
May 21, 1980 Director General of the Patent Office 1981 Patent Application No. 246548 & Name of Invention Casting Device & Relationship with the Amendment Person Case Applicant Address Kyoto 22 name of 5 Higashino Kita Inoue-cho, Yamashina-ku, Ichi
Agent to Kyocera Corporation Representative Kazuo Ina Mori (and 2 others) 55
0 Address 1-12-14 Kyomachibori, Nishi-ku, Osaka (Tensin Building)
The “Claims” column, “Detailed Description of the Invention” column, “Brief Description of Drawings” column and drawing “Figure 2” of the specification
, ``Figure 3'', ``Figure 4''& Contents of Amendments - 8. Contents of Amendments (I) The description is amended as follows. (1) Amend the claims on pages 1 to 3 as shown in the attached sheet. (2) Delete the line 8 from the bottom of page 3 that says "Injection layer socket." (3) In the 7th line from the bottom of page 3, the phrase “pressurize” will be corrected to “pressure cast.” (4) In the fourth and third lines from the bottom of page 3, the phrase ``Some judgment is required'' has been corrected to ``A lot of judgment is required.'' (5) On page 4, line 9, "vitreous" should be corrected to "glass." (6) Page 5, line 11, ``I tried to obtain it... (on the way)... in Figure 2'' was replaced with ``The second casting device was used to obtain it.'' I will correct it. (7) On the 4th line from the bottom of page 5, the phrase "with the heat generating means (2)" will be corrected to "with the inside of the heat generating means (2)." (8) Page 7, lines 8 to 4 from the bottom “The code aa is...
(In the middle of the passage) ``The material is made of wood,'' is corrected to ``The material used is the insulation material.'' (9) In the 4th line of page 8, the phrase ``equipped with an element'' will be corrected to ``equipped with an element.'' (To) Correct “Crucible (b)” on page 81, line 8 to “Crucible (3)”. (ID page 8, line 8 from the bottom, “heating means (71) J”
Correct with insulation means (71) J. (Company) Insert ``, funnel-shaped surface'' between ``arc surface'' and ``either'' on the 2nd line of page 9. (131, page 9, line 9, ``nt (43) J'' should be corrected as ``nt (431) J.'' Q41, page 9, 9th line from the bottom, ``Continued'', should be corrected to ``nt (43) J.'') (The 8th line from the bottom of page 151aExo, ``Temperature hold timer'' is corrected to ``Temperature tether timer.''"Releasebutton" should be corrected to "Release button". αη Page 11, line 8, "Mold socket α4" should be corrected to "R-ID card holder 0η". Q81 Page 11, bottom Insert "pressurize" between "Pressure" and "Setting" on the 5th line. From the 3rd line to the 2nd line from the bottom of page α91jH11, "Table az
Delete the statement "The temperature rises to the furnace body (11)." Trouble: On page 12, line 5, "vitreous ceramic raw materials" should be corrected to "glass ceramic raw materials, etc." (2N) Page 12, 7th line from the bottom, “Together” and “Table”
Masu. (Support) In the second line from the bottom of page 12, "descent" is corrected to "start of descent." □□□Page 13, lines 10 to 111, vitreous ceramics (castable ceramics)" will be corrected to "castable ceramics." (241, page 14gg, line 4, "(412 )but···(
(413)
) is located between the sprue (5) and the sprue (41).
” and correct it. (25) On page 14, line 5, replace “mass” with “capacity”
I will correct it. (b) Delete the line 10 of page 14 that says ``The heat capacity is increased.'' @ Page 114, 2nd line from the bottom, ``The molten material (6) is'' and ``Receive.'' (2) Page 17, 6th line, ``13...Cast history operation section''・Correct it as "Furnace body support part". (n) Replace the drawings “Figure 2,” 1, “Figure 3,” and “Figure 4” with the attached drawings “Figure 2,” “Figure 3,” and “Figure 4.” 9. List of attached documents (1) Claims (amendment) 1 copy (2) Drawings! Figure 2'', ``Figure 3'', ``Figure 4'' 1 copy (3) Address change notification 1 copy - Above 12, Claims (Amendment) L Standing in a closed chamber that can be depressurized and pressurized freely. A cylindrical electric heating means provided, a vertically elongated melting crucible installed within the electric heating means, a mold connected below the melting crucible, and a lower part of the socket of the melting crucible. The mold is formed by a sprue that communicates with the sprue drilled in the mold, and the casting melt melted at the socket is held by its surface tension, and when the inside of the sealed chamber is pressurized, it becomes stronger. A casting apparatus characterized in that a casting melt is press-fitted into a mold through the sprue and cast. & A cylindrical sealed chamber equipped with depressurizing and pressurizing outlet pipes, a cylindrical electric heating means installed approximately in the center of this sealed chamber, and a melting crucible and a mold placed in the lower part of the sealed chamber. The melting crucible is placed in airtight contact with a table, and the socket of the melting crucible is located within the effective heating zone of the electric heating means when the table is in contact with the lower part of the chamber. A casting device characterized by: & A ring-shaped space equipped with separate depressurization and pressurization derivation pipes is formed at the bottom of the closed chamber equipped with depressurization and pressurization derivation pipes, and a table on which the melting crucible and mold are placed is arranged below the space. . A casting apparatus, characterized in that the space is depressurized through the outlet pipe communicating with the space, and the table is held by suction at the lower part of the sealed chamber. The casting device according to any one of claims 1 to 3, wherein the melting crucible and the mold are integrally formed. 5. The casting apparatus according to any one of claims 1 to 3, wherein the melting crucible and the mold are constructed separately and are a connected body. 6. The casting apparatus according to any one of claims 1 to 3, wherein the socket of the melting crucible converges with the opening of the sprue with a curved surface. 7. The casting apparatus according to claim 6, wherein the curved surface of the socket is any one of an elliptical curved surface, a narrow narrow curved surface, and a circular arc curved surface. & The casting device according to claim 6, wherein the curved surface of the socket is a funnel-shaped surface. Procedural amendment (voluntary) 1. Display of the case 1982 Patent Application No. 246548 2, Name of the invention Casting device 8, Person making the amendment Relationship to the case Applicant address 22 Name, 5, Higashino Kitainoue-cho, Yamashina-ku, Kyoto City
Kyocera Corporation Representative Kazuo Ina Mori (and 2 others) 4, Agent 550 7, Full text of the specification to be amended, Drawing ``Figure 2'' attached to the procedural amendment dated May 21, 1980, `` 8. The contents of the amendments “Fig. 2”, “Fig. 8” and “Fig. 4” are attached to the attached drawing “Fig. 2”.
"Fig. 8" and "Fig. 4". 9. List of attached documents (1) Specification (full text amended) 1 copy (2) Drawings "Figure 2", "Figure 8", "Figure 4" 1 copy Specification (full text amended) 1. Name Casting Apparatus 2, Claim 1, A cylindrical electric heating means installed upright in a closed chamber that can be freely depressurized and pressurized, and a vertically elongated melting crucible installed within this electric heating means. , a mold connected below the melting crucible, and a sprue that communicates the lower part of the socket of the melting crucible with a sprue drilled in the mold. A casting device characterized in that the object is held by its surface tension, and by pressurizing the inside of the closed chamber, the molten material for Zenzukuri is press-fitted into the prayer mold through the sprue to perform koji-making. . 2. A cylindrical sealed chamber equipped with depressurization and pressurization outlet pipes, a cylindrical electric heating means installed approximately in the center of this sealed chamber, and a melting crucible and a hollow mold at the bottom of the sealed chamber. The table on which the melting crucible is placed is brought into airtight contact with the lower part of the chamber, and the socket of the melting crucible is positioned within the effective heating zone of the electric heating means. A casting device characterized by: 8. At the bottom of the sealed chamber equipped with depressurization and pressurization derivation pipes, a ring-shaped space is formed with separate depressurization and pressurization derivation pipes, and a table is placed below the space on which the melting crucible and mold are placed. A casting apparatus characterized in that the table is suction-held at a lower part of the closed chamber, and the pressure of the space is reduced through the outlet pipe communicating with the space. 4. The casting apparatus according to any one of claims 1 to 3, wherein the melting crucible and the mold are integrally formed. 5. Claims 1 to 8, in which the melting crucible and the cylindrical shape are constructed separately and are a connected body.
The casting device according to any one of paragraphs. 6. The casting device d according to any one of claims 1 to 8, wherein the socket of the melting crucible converges with the opening of the melting port with a curved surface. 7. The casting apparatus according to claim 6, wherein the curved surface of the socket is any one of an elliptical curved surface, a traditional artifact curved surface, and a circular arc curved surface. 8. The casting apparatus according to claim 6, wherein the curved surface of the socket is a funnel-shaped surface. 8. Detailed Description of the Invention The present invention relates to a casting apparatus suitable for pressure casting using gas. For example, to cast crown dentures, artificial teeth, etc., centrifugal casting and pressure casting using the lost wax method have been carried out using pleasure metals, non-pleasure metals, etc.; In this case, a method has been adopted in which the upper part of the socket of the mold is covered with a water-containing cap, and the water in the cap is rapidly vaporized by the heat of the molten metal, and pressure casting is performed using steam pressure or compressed air. As is clear from this method, conventional gas pressure casting is primitive and relies heavily on the operator's technical and professional judgment, and the problems include poor reproducibility. is left behind. In view of these problems, the present invention provides an apparatus that can automatically and synchronously pressurize gas and pour molten metal, thereby performing accurate pressure casting with high reproducibility. In addition, the present invention provides a device that can automatically link the melting and casting of casting materials, and the melting and casting parts are small enough to be placed on a table even when combined. Moreover, it has the feature that it is extremely easy to set and take out the mold. The device according to the invention is also suitable for casting glass ceramics as well as the metals or alloys mentioned above. The preferred embodiment of the present invention will be described in more detail below with reference to the drawings; Fig. 1 is a front view showing one embodiment of the present invention, and Fig. 2 shows the mold operation of Fig. 1. Fig. 8 is a longitudinal sectional front view of the melting crucible and mold in the furnace body, raised together with the table, and set in the furnace body. FIG. 4 is a longitudinal sectional front view of only the essential parts showing another embodiment of the crucible and mold shown in FIG. 8. First, the first invention is a cylindrical electric heating means (2) (hereinafter simply referred to as heating means) installed vertically in a closed chamber (1) that can freely reduce and pressurize the pressure, as shown in FIG. ), and a vertically elongated melting crucible (3) that can be raised and lowered within this heating means (2).
) and a mold (
4), and a sprue (5) that communicates the lower part of the socket (811) of the melting crucible (3) with the sprue (411) of the mold (4), 4)
If there is no substantial gas pressure difference between the
The second invention is a casting device in which a casting @ melt (6) molten in the above-mentioned sprue (6) can enter the sprue (5) due to its surface tension and stay there without falling. A cylindrical sealed chamber (1) having a depressurizing and pressurizing outlet pipe (8) penetrating the peripheral wall and connecting a small diameter cylindrical part (9) at the bottom.
This chamber (1) has a cylindrical resistance heating means (2) installed vertically at the lower center, and a heat insulating means arranged in the chamber (1) surrounding this heating means (2). (7), a furnace body portion 11ρ including a gas passage μ which communicates the outlet pipe (8) with the inside of the heat generating means (2), and a small diameter cylindrical portion ( 9) that can be brought into contact with the table (1) from below, a mold (4) placed on the ring of this table, and a sprue (411) of this mold (4).
A sprue (5) that communicates with the sprue (5) is provided at the bottom of the socket (811), and a vertically long gate (5) connected to the upper part of the mold (4) is provided.
The table (I) includes a melting crucible (3) and a prayer-type operating section connected directly below the furnace body (l).
With the pier in contact with the small diameter cylindrical portion (9) from below,
The socket (811) of the melting crucible (3) is the effective heating zone (4) of the heat generating means (2) [the length of the heat generating part Qυ which shows a particularly high value in the heating temperature distribution and has a nearly uniform temperature]. The zone including the central part of the direction is called this. ]
Inside, the molds (4) are respectively arranged in the small diameter cylindrical portions (9), and if there is no substantial gas pressure difference between the sockets (811) and the inside of the molds (4), The casting melt (6) melted in the socket (811) can enter the sprue (5) due to its surface tension and stay there without falling. When pressure casting is performed by closing the bottom of the body (lυ) with a table (6) and setting a mold, make sure that the table (6) does not separate from the furnace body O■ even under the pressure. This design takes into account the following considerations, and the outside of the small diameter cylinder part (9) of the second invention is made into a ring-shaped space (]
4) is provided at the lower part of the chamber (1), and a depressurizing and pressurizing outlet pipe θQ passing through the cylindrical wall 00 is provided to separate and surround the chamber (1) from depressurizing to pressurizing. Even when the mf table (2) is attached to the bottom of the chamber (1) by reducing the pressure in the ring-shaped space (I→) independently of the chamber (1). The 2nd class 8 invention will be explained in more detail below.
) is a mold holder that receives the mold (4) and places it on the table @. In the case of the figure, the bottom of this pedestal ση is placed on the table Qa with a flat surface. When pressurizing the mold (4) during casting after reducing the pressure in the mold (4) by making contact with multiple surfaces that can increase the contact area, the positive pressure in the chamber (1) will increase the pressure from the bottom of the mold (4) to the mold (4). (4) In some cases, it may be desirable to take measures to make it difficult to press fit inside. The lower part of the heat insulating means (7) is a ring-shaped heat insulating material made of ceramic fiber, and the upper part also serves to hold the heating means (2) in alignment. The heat insulating material is 0, for example, made of ceramic fiber molded into a ring shape using a binder. The heating means (2) is a cylindrical, for example, a ceramic resistance heating element, and forms a heating part ■υ equipped with a resistance heating element in the lower part of the cylindrical body (a) which is made by combining left and right halves, and this heating part QI). There is a socket (81) for the crucible (3) in the effective heating zone (1).
1) is arranged. Inside the upper opening of the cylindrical body α),
The center through hole (191) and the thermocouple that detects the temperature inside the heat generating part ■υ are sealed with a stopper cap Cj9, which is sealed, and the center through hole (191) is used as a heat insulating means). ■It opened to traffic. The lower end of the cylindrical body 1'1 is held by a ring support (A) on which the heat insulating means (C) is mounted and held, and the upper part of the body 1' is bound by a tight band (A). A lid (A) is fixed to the upper end opening of the chamber (1) with a set screw, and a viewing window hole (281) is inserted through the center of the lid. The glass or other transparent window plate (window sill member (3υ) holding the illusion is attached with a set screw. The socket (811) of the crucible (3) is attached to the sprue (5). Convergent curved surface, such as ellipsoid ih7.1 radial curved surface,
It has either an arcuate surface or a funnel-shaped surface. Sprue (5
) is the diameter of the melt (6) in the socket (811) that does not fall through the sprue (5) when there is no substantial pressure difference between the crucible (3) and the mold (4). The dimensions shall be selected so that it can remain in the sprue (5) due to surface tension. In the example in Figure 2, the crucible (3) and mold (4) are integrally molded, and the investment (481) is used across both.
4) Those that are separate and connected as one body will be described later. The outlet pipe (8) is connected to a vacuum pump (not shown). The cross section of the cylinder wall (10 extending to the bottom of the chamber (1) is y
A type I is shown, and the table (J) is in contact with the seal gasket from below through the lower end of the footrest (151) of this cylinder wall 0υ and the lower end of the small diameter cylinder part (9), respectively. In this case, the ring-shaped space +, 14 is sealed, so when exhaust is exhausted from the side of another outlet pipe a, the pressure inside this space Ua is reduced and the table @
is suctioned and held on the footrest (151). Next, let's talk about the mold operation @+13 located directly below the furnace body part u3. An operation opening (2) opened at the base ■ and the frames C1 and C on both sides,
Table 1: Mold is located 112 times in this operation opening (B) at the lowest adjacent position, and is released to the highest position 1d to reach the standby state for pouring as shown in Fig. 2. cradle iJη
, a melt-casting member including a mold (4) and a crucible (3);
(to the lifting arm that lifts and lowers these while maintaining the horizontal level) and a coil spring (to) for elastically maintaining the horizontal level.
This includes: And on the front of the base, there is a power supply
N10FF switch θQ1 rise, fall switch I41
), Furnace temperature display section θ Main furnace temperature setting switch ■, Temperature body timer 0, Pressure timer (7), Decompression setting dial 1, Furnace pressure gauge o7), Pressure setting dial),
The operation switches and buttons, such as the start button, the standby button (in the standby box), and the release button (in the box), are worn out. Note that the lift arm (to) is raised and lowered by a 4u movable elevator groove (not shown). In addition, in the above example, the table @ is raised and lowered, but it is also possible to have the chamber (1) placed next to it. The mold operating part u is operated to move the melted and cast member to the furnace body part 11.
The following describes the procedure for melting and manufacturing the mold by setting it at υ and taking out the W mold. (a) Heating of the heating means (2) of the furnace body (II) is started by turning on the power switch θ1 with the table @ in the lowered position in FIG. Place the mold pedestal q on the chill pull @ and use the table lift switch (6) to raise the table (2) to the furnace body (1) side.
l) The interior is automatically preheated to 850°-500°C. (b) Set the casting temperature using the furnace temperature setting dial (■), and then set the holding time of that temperature using the temperature mooring timer. The pressure until the end of this temperature mooring is controlled by the furnace pressure reduction setting dial (G), and the pressure at the time of pressurization following release of the pressure reduction is controlled by the pressure setting dial). (C) Next, press the standby button (A) and the furnace body fil
) will rise to the set temperature. For example, a lamp (not shown) flashes when the set temperature is reached. (d) Table @ by table lowering switch ◇
Lower the mold (4) and crucible (3), load gold M (alloy) for melting, glass ceramic raw materials, etc. into the socket (811) of this crucible (3), and immediately press the start button @ Push the samurai. As a result, the table (1'J) rises to the furnace body (1υ), and then inside the furnace body #ζ1υ, the pressure is reduced to the previously set pressure, the temperature rises to the set temperature, and the hold is held for the set time. Once the depressurization is finished, the depressurization stops and casting is performed under pressure (usually with air, but in the case of metals that are easily oxidized, pressurization with inert gas such as argon) according to the previously set pressure and time. For example, after the pressure returns to normal pressure with a buzzer sound, the table ++9 lowers and the power switch @1 is first turned on.
Returns to the previous state in Y order. This pressure casting is done fully automatically. Depressurization and pressurization are done through the outlet pipe (8), and
'+8), depressurizing and pressurizing the mold (4) is done through gas passage H1l.
Of course, it is done through the process. On the other hand, the ring-shaped space +1. Until the table (6) starts to descend, the table (19) is suctioned and held in the lower end opening of the ring-shaped space (I4) and the mold (4 ) This prevents the table 4 from coming off downward even if the inside of the table 4 is pressurized. Note that interruptions during standby processing and automatic operation are performed using the release button 5]).The table t12 is lowered. After the casting process is completed, the mold (4) is dismantled, the product is extracted, and the new mold is set in the crucible mold holder and used for the next operation in the same manner as above. In the case of dental crowns, the material is
Although pleasure metals, non-pleasure metals, or castable ceramics are used, it is clear that pressure casting other than dentistry can also be applied. In the embodiment illustrated in FIG. 1 and FIG. 2, an example was shown in which the melting crucible (3) and the mold (4) were integrally molded, but FIG. ) shows an example of forming a hot water reservoir. As shown in the figure, a rabbit meat expansion opening <B is provided at the lower end of the sprue (5) of the vertically long cylindrical crucible (3), and the mold (
4) A cylindrical recess (412) into which the crucible (3) is fitted is provided at the upper end, and a space between this recess (412) and the sprue (411) corresponds to the rabbit meat expansion opening. Rabbit meat reduction openings (418) are formed, and when the crucible (3) and mold (4) are fitted and connected, 11 openings are formed). (41B) forms a sump (414) at the sprue (5) and the sprue (4ρ [KJ) to replenish the m'lPh deficiency of the stored product. Similarly, another example is shown in which the crucible (3) and mold (4) are separate bodies, and in this example, the diameter of the central part of the crucible (3) is reduced to reduce the heat capacity and J. The continuous upper and lower parts are enlarged in diameter to reduce the leakage of radiant heat inside the furnace to the outside, and the connection between the crucible (3) and the mold (4) is This differs from the previous example in that the connecting part ζ→ of the mold (4) is shaped into a truncated cone to prevent the investment material of the crucible (3) from entering the sprue (411) of the vj type (4) when pressurizing the gas. Next, the functions and effects of the first to eighth inventions will be described. In the first invention, the socket (811
) The melt (6) in the socket (all
) and the inside of the pocket mold (4), when there is no real Yq gas pressure difference, it expands and opens into the socket (811) and maintains high fluidity while being heated. However, as soon as pressurization of the chamber (1) is started, the metal is simultaneously poured into the mold (4) through the sprue (5) Q and the sprue (411), and gas flows in from above. The positive pressure presses the poured metal down to the smallest detail, allowing for casting with high dimensional accuracy. Then, the crucible (3) is raised and lowered into the heat generating means (2), and by placing it in the effective heating zone (II) in the heat generating means (2), it is possible to perform casting under high temperature with high thermal efficiency. Due to the interaction between the molten material and the mold (4), the heat loss during the falling of the molten material (6) can be minimized.Also, since the pouring is done synchronously with the introduction of gas, it is possible to In the second invention, while retaining the above advantages, the furnace body part (il) and the mold operating part +t3 are vertically connected, and the mold operating part α pull and the After the mold (4) and crucible (3) have been set, the mold (4) and crucible (3) are automatically raised to perform casting, and after casting, they are lowered to take out the product and set it again, thereby reducing vertical space. This makes it possible to perform efficient pressurized casting in a small space by making use of the advantages of the second invention and reducing the pressure in the lateral direction. Even when the pressurization is changed from
) is settled and held on the underside of the furnace body (1) without falling downward.・The furnace body (1) can be removed from the table using the same depressurization method as the one used for This has the added benefit of making it possible to maintain the @.Thus, the present invention eliminates the shortcomings of the known techniques, which were poor reproducibility despite the need for skilled technicians. 4. Brief explanation of the drawings Figure 1 is a front view showing one embodiment of the present invention, and Figure 2 is a front view showing one embodiment of the present invention.
Fig. 3 is a longitudinal sectional front view of the melting crucible and mold in the IM operation section raised together with the table and set in the furnace body, and Fig. 3 is an embodiment in which the crucible and mold are separate bodies. FIG. 4 is a longitudinal sectional front view of only the essential parts showing another aspect of the crucible and mold shown in FIG. 3. (Explanation of symbols) 1... sealed chamber, 2... hypochondriacal heating means, 3...
... Melting crucible, 4... Mold, 5... Place mouth, 6...
- Molten material for casting, 7... Insulating means, 8.16... Outlet pipe for depressurization and pressurization, 9... Small diameter cylindrical part, 10... Gas passage, 11... Furnace body part, 12... table, 13...
...Furnace support part, 14...Ring-shaped space, 15...
Cylinder wall, 311... Socket, 411... Sprue, l.
...Effective heating zone. -That's all-

Claims (1)

[Scope of Claims] L: A cylindrical electric heating means installed upright in a closed chamber that can be freely depressurized and pressurized, a vertically elongated melting crucible installed within the electric heating means, and the melting crucible. It consists of a sprue connected to the lower part of the melting crucible, and a sprue that communicates the lower part of the socket of the melting crucible with the sprue drilled in the mold. A casting apparatus characterized in that the molten material is pressurized in the sealed chamber, and the melt is press-fitted into the mold through the sprue for casting. & A cylindrical sealed chamber equipped with depressurization and pressurization outlet pipes, a cylindrical electric heating means installed approximately in the center of this sealed chamber, and a melting crucible and a poet placed at the bottom of the sealed chamber. A table is brought into contact with the lower part of the chamber in an airtight manner, and with the table in contact with the lower part of the chamber,
A casting apparatus characterized in that the sockets of the melting crucible are located within effective heating zones of the electric heating means. 88 A ring-shaped space equipped with separate depressurization and pressurization derivation pipes is formed at the bottom of the closed chamber equipped with depressurization and pressurization derivation pipes, and a table on which the melting crucible and mold are placed is placed below the space. A casting apparatus characterized in that: the space is depressurized through the outlet pipe communicating with the space, and the table is held by suction at the lower part of the sealed chamber. The casting apparatus according to any one of claims 1 to 8, wherein the melting crucible and the mold are integrally formed. 5. The casting apparatus according to any one of claims 1 to 8, wherein the melting crucible and the mold are constructed separately and are a connected body. 6. The casting apparatus according to any one of claims 1 to 3, wherein the socket of the melting crucible converges with the opening of the sprue with a curved surface. 7. 7. The casting apparatus according to claim 6, wherein the curved surface of the socket is any one of an elliptical curved surface, a cylindrical curved surface, and a circular arc curved surface.