JP2000073106A - Hot press device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot press capable of enhancing the soaking property of powder raw material, improving the flexibility of operation, shortening heat treatment time, shortening cooling time and simplifying equipment. SOLUTION: This hot press device has a furnace body 32 of a pressure resistant structure which is disposed in a press frame 31, a heating chamber 34 which is disposed in this furnace body and is enclosed by thermally insulating material walls 33, a mold 38 which takes the powder raw material 35 supplied near the central part of this heating chamber therein and simultaneously heats and pressurizes an electrical heater 36 and a resistance heater 37 in a pressurized gaseous N2 atmosphere to form a pressure molded material 35, a pressurized gas supply device 39 which supplies the pressurized gas into the furnace body, a lifting opening/closing device 44 which freely opens and closes apertures 42, 43 arranged in the upper and lower parts of the thermally insulating material walls of the heating chamber and a cooling fan 45 which cools the inside of the furnace body and circulates the pressurized gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a batch-type hot press apparatus for press-forming a powder material in a mold.

[0002]

2. Description of the Related Art A hot press device is a device in which powder materials such as metals and ceramics are filled in a mold and pressure-molded at a high temperature.
There are known three types of heating means of (B) induction heating type and (C) energization heating type.

[0003]

As schematically shown in FIG. 2, (A) a resistance heating type hot press apparatus is a method in which a mold 2 filled with a powder material 1 is pressed from above and below by a ram 3 while the mold 2 is pressed. The resistor 4 is heated from outside by heating the powdered raw material 1 through the mold 2 by resistance heating, and has high heat uniformity and good operation flexibility, but has a slow heating rate. There is.
(B) The induction heating type hot press device winds a coil 5 outside the mold 2 and energizes this coil to heat the powder raw material 1 by induction heating. There is an advantage that the heating rate is relatively fast,
There is a drawback that heat uniformity and operation flexibility are inferior.
(C) The electric heating type hot press device has upper and lower rams 3
During this time, the DC power source 6 is energized to heat the powder raw material 1 by the heat generated by the powder raw material 1 itself. Since the powder raw material 1 can be directly heated, a heating rate about 10 times that of the resistance heating type can be obtained. Although it has an advantage, it has a disadvantage that it is easily heated locally, has low uniformity, and has poor operation flexibility.

[0004] Furthermore, the above-mentioned three systems are batch systems, and the batch systems of these systems have a problem that the productivity of the press-formed material is low. On the other hand, as a hot press apparatus which has made these systems continuous, for example, a "hot press apparatus" (Japanese Patent Publication No. 6-53885) has been proposed.
As schematically shown in FIG. 3, the hot press device 10 includes:
A vacuum vessel 13 on which a transport cart 12 for transporting the sample capsule 11 travels; a front chamber 14 partitioned by respective partition doors from the entrance side into the vacuum vessel 13; a hot press moving chamber 15;
A cooling chamber 16 is sequentially provided, and a hot press moving chamber 15 is provided.
, And a hot press chamber 17 disposed above. On the inner surface of the hot press chamber 17, a heat insulating material 2 having a die 18 at the lower end and an upper ram 19 which can be raised and lowered is arranged.
0, and a heater 2 around the die 18.
1 and the like are provided. On the other hand, the telescopic tube 2 provided below the floor of the hot press moving chamber 15 is located immediately below the die 18.
The lower ram 2 which raises and inserts the sample capsule 11 into the die 18 and presses up and down in cooperation with the upper ram 19 at 2
3 are arranged. In this manner, the sample placed in the sample capsule 11 from the upstream side and conveyed is pressed and pressed by the upper and lower rams 19 and 23 in a vacuum state and a normal temperature state, and the heater 21 near the die 18 is energized continuously. Sintered material is obtained.

[0005] However, as shown in FIG. 3, the conventional continuous hot press apparatus 10 is energized and heated in a vacuum, that is, in a negative pressure (reduced pressure) state. It took a long time for heat treatment. In addition, since it is heated from normal temperature to high temperature,
It takes a considerable amount of time to cool the sample, the die and the like, and there is a problem in shortening the production cycle of the press-formed material and in productivity.
Furthermore, since the respective processing chambers are continuously provided in the vacuum vessel, the molding line is longer than that of the batch type, and the building is high because the hot press room has a two-story structure, and the equipment cost is high. There were also problems.

The present invention has been made to solve the various problems described above. That is, the object of the present invention is to increase the heat uniformity of the powder raw material, improve the flexibility of operation, reduce the heat treatment time, shorten the cooling time, and further simplify the equipment. It is to provide a hot press apparatus that can perform the hot press.

[0007]

According to the present invention, a pressure-resistant furnace body (32) provided in a press frame (31).
And a heating chamber (3
4) and the powder raw material (3) supplied near the center of the heating chamber.
5) Take in and apply an electric heating device (3
6) A mold (38) which simultaneously heats and pressurizes the resistance heating device (37) to form a press-formed material (35 '), and a pressurized gas supply device (39) for supplying a pressurized gas into the furnace body. When,
An elevating opening / closing device (44) for freely opening and closing an opening provided in upper and lower portions of a heat insulating material wall of the heating chamber; and a cooling fan (45) for cooling the inside of the furnace and circulating a pressurized gas. A hot press apparatus is provided.

[0008] According to the configuration of the present invention, since the batch type single equipment is used, the equipment can be simplified, the molding line can be shortened, and the equipment cost can be reduced. In a pressurized gas atmosphere (for example, N2 or nitrogen gas) supplied by a pressurized gas supply device (39), the pressurized gas is carried into a mold (38) in a heating chamber surrounded by a heat insulating material wall. Powder raw material
Since the heating and pressurization can be performed simultaneously by using both the electric heating device (36) and the resistance heating device (37), the time required for the heat treatment can be shortened, and the press-formed material can be quickly obtained. In addition, an elevating opening / closing device (44) for freely opening and closing an opening provided in upper and lower portions of a heat insulating material wall of the heating chamber, and a cooling fan (45) for cooling the inside of the furnace and circulating a pressurized gas are provided. Therefore, the press-formed material in the high-temperature heated state in the mold and the peripheral equipment can be cooled quickly and easily, and the cooling time can be shortened.

According to a preferred embodiment of the present invention, the electric heating device (36) comprises upper and lower pressing rams (51, 52) for pressing the powder raw material supplied into the mold, It has a heating element (53) arranged between the rams, and a ram energizing device (54) for energizing between the upper and lower pressurizing rams. According to this configuration, the heating element starts generating heat to a predetermined temperature by energizing the respective pressurizing rams from the ram energizing device (54) together with pressurization by the upper and lower pressurizing rams (51, 52). The powder raw material in the mold sandwiched during this time can be quickly and easily heated, and the uniform temperature can be improved. Further, even when the electric resistance of the powder raw material is small and self-power generation is small, a faster heating rate can be obtained by the heating element.

The resistance heating device (37) is a resistance heater (56) surrounding the mold, and heats the mold from the outside by energizing the resistance heater. According to this configuration, by using the resistance heater in combination with the conventional resistance heating, the uniformity of the powder raw material is further improved, the flexibility of operation is improved, and a high heat treatment speed is obtained.

Further, the pressurized gas supply device (39) is
A blower (57) for supplying pressurized gas into the heating chamber and a cyclone (58) for sending fresh pressurized gas to the blower. According to this configuration, the inert gas N2 gas, which has been freshened by the cyclone and has a predetermined pressure higher than the atmospheric pressure, can be supplied to the heating chamber by the blower, that is, the N2 gas state of the present invention and the pressure higher than the atmospheric pressure can be supplied. Heating in a pressure state can raise the temperature in about half the time compared to heating in a vacuum state and negative pressure, and the heat treatment time can be reduced by high-speed heating.

Further, the lifting opening / closing device (44) is provided with a flange (6) which can be raised and lowered in the opening between the pressure ram and the heat insulating material wall.
5, 66) and a hydraulic cylinder (67, 68) attached to the heat insulating material wall so that the flange can be moved up and down.
According to this configuration, the flange (65, 66) which can be lifted and lowered in the vertical opening provided between the pressurizing ram and the heat insulating material wall can be operated and lifted by the hydraulic cylinder to open the opening. The high temperature generated in the press-formed material and the peripheral equipment which have been heated and pressed in the gas state and the pressurized state of the atmospheric pressure or higher can be easily discharged from the heating chamber into the furnace. Therefore,
The cooling time can be shortened and the productivity can be improved.

Further, the pressurized gas in the furnace is heat-exchanged by a water-cooled furnace body wall or a heat exchanger. According to this configuration, if a water-cooled furnace body wall is used together with the cooling fan that cools the furnace body and circulates the pressurized gas, the N2 gas can be cooled by contacting the water-cooled wall and the cooling processing speed can be increased. Can be accelerated.
In addition, if a heat exchanger is provided in the furnace, cooling can be performed more easily and quickly by heat exchange, including N2 gas and peripheral equipment.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. In the drawings, common parts are denoted by the same reference numerals. FIG. 1 is a cross-sectional configuration diagram of a hot press apparatus according to the present invention. As shown in the drawing, a batch-type hot press apparatus 30 according to the present invention includes a pressure-resistant, spherical furnace body 32 provided in a press frame 31 and a heat insulating material wall 33 disposed in the furnace body 32. The heating chamber 34 and the powder raw material 35 supplied near the center of the heating chamber 34 are taken in, and the heating device 36 and the resistance heating device 37 are simultaneously heated and pressurized in a pressurized gas atmosphere. A mold 38 for forming a molding material 35 ';
A pressurized gas supply device 39 for supplying a pressurized gas into the furnace body 32
An elevating opening / closing device 44 for opening and closing openings 42 and 43 provided in upper and lower portions of a heat insulating material wall 33 of a heating chamber 34; and a cooling fan 4 for cooling the inside of the furnace body 32 and circulating a pressurized gas.
5 is provided. Since the batch type single equipment is used, the equipment can be simplified, the molding line can be shortened, and the equipment cost can be reduced.

Further, in FIG.
The upper pressurizing ram 51 which can be moved up and down by a hydraulic cylinder 50 attached to the upper part of the press frame 31 for pressurizing the powdery raw material 35 supplied into the mold 38, and the lower pressurizer arranged at the lower part of the press frame 31 Ram 52, a circular heating element 53 disposed between the powder raw material 35 and the upper pressure ram 51
And a ram energizing device 54 composed of a DC power supply for energizing between the upper and lower pressurizing rams 51 and 52. With this, the heating element starts heating to a predetermined temperature by applying current from the ram energizing device to each of the pressurizing rams together with pressurization by the upper and lower pressurizing rams,
The powder raw material in the mold sandwiched during this time can be quickly and easily heated to increase the uniformity. Furthermore, even when the resistance to war is small and the self-power generation is small,
A faster heating rate can be obtained by the heating element. In addition,
As the powder raw material 35 of the present invention, for example, conductive powder of metal powder or non-conductive powder of ceramic powder is used.

Further, as shown in FIG.
Reference numeral 7 denotes a resistance heater 56 surrounding the mold 38, and the mold 38 is externally heated by energization of the resistance heater 56. According to this configuration, by using the resistance heater in combination with the conventional resistance heating, the uniformity of the powder raw material is further improved, the flexibility of operation is improved, and a high heat treatment speed is obtained.

The pressurized gas supply device 39 is connected to the heating chamber 3.
A blower 57 for supplying a pressurized gas (N2 gas) of an inert gas into the inside 4, a cyclone 58 for sending fresh N2 gas to the blower 57, and a flow valve 59 for adjusting the flow rate of the N2 gas.
Consists of As a result, N2 gas freshened by the cyclone and supplied at a predetermined pressure higher than the atmospheric pressure can be supplied to the heating chamber by the blower. That is, the heating in the N2 gas state and the pressurized state above the atmospheric pressure can raise the temperature in about half the time as compared with the conventional heating under the vacuum state and the negative pressure, so that the heat treatment time can be reduced by the high-speed heating. . In this figure, 6
2 is a pressure-resistant bellows.

The elevating opening / closing device 44 is provided with respective openings 42 between the upper and lower pressing rams 51 and 52 and the heat insulating material wall 33.
It comprises flanges 65 and 66 which can move up and down inside 43 and hydraulic cylinders 67 and 68 which are attached to the heat insulating material wall 33 and make the flanges 65 and 66 move up and down. As a result, a vertically movable flange provided between the pressurizing ram and the heat insulating material wall can be lifted and opened by operating the hydraulic cylinder with a hydraulic cylinder. From this opening, the N2 gas state and the pressure higher than the atmospheric pressure can be applied. The high temperature generated in the press-formed material and peripheral equipment that has completed heating and pressurization in the pressure state can be easily released from the heating chamber into the furnace. Therefore, the cooling time can be shortened and the productivity can be improved.

Further, the inert N 2 gas in the furnace body 32 is brought into contact with a furnace wall 69 having a water-cooled structure to exchange heat. Alternatively, heat is exchanged in a heat exchanger 70 having a curved tube shape as shown by a dotted line in the figure. According to this configuration, if the inside of the furnace body 32 is cooled and N2 gas is circulated to form a water-cooled furnace body wall together with the cooling fan 45 rotated by the motor 71, the N2 gas is brought into contact with the water-cooled inner wall. Can be cooled, so that the cooling processing speed can be increased. In addition, if a heat exchanger is provided in the furnace, cooling can be performed more easily and quickly by heat exchange, including N2 gas and peripheral equipment.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, the present invention can be performed in a reducing gas atmosphere such as a hydrogen gas in addition to an inert N2 gas atmosphere. Of course.

[0021]

As described above, the hot press apparatus of the present invention improves the uniformity of the powder raw material, improves the flexibility of operation, and shortens the heat treatment time.
In addition, the present invention has excellent effects such as shortening the cooling time and further simplifying the equipment.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram of a hot press device according to the present invention.

FIG. 2 is a schematic view of a conventional hot press device.

FIG. 3 is a schematic view of a conventional continuous hot press apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Powder raw material 2, 38 Mold 3 Ram 4 Resistor 5 Coil 6 DC power supply 10, 30 Hot press device 11 Sample capsule 12 Carriage truck 13 Vacuum container 14 Front room 15 Hot press moving room 16 Cooling room 17 Hot press room 18 Dice 19 Upper ram 20 Insulating material 21 Heater 22 Telescopic tube 23 Lower ram 31 Press frame 32 Furnace body 33 Insulating material wall 34 Heating chamber 35 Powder material 35 'Press forming material 36 Electric heating device 37 Resistance heating device 39 Pressurized gas (N2 Gas) supply device 42, 43 opening 44 elevating opening / closing device 45 cooling fan 50 hydraulic cylinder 51 upper pressurizing ram 52 lower pressurizing ram 53 heating element 54 ram energizing device 56 resistance heater 57 blower 58 cyclone 59 flow valve 64, 66 flange 62 Pressure-resistant bellows 67, 68 Hydraulic cylinder 6 Furnace wall 70 heat exchanger 71 motor

Claims (6)

[Claims] 1. A pressure-resistant furnace body (32) provided in a press frame (31), a heating chamber (34) disposed in the furnace body and surrounded by a heat insulating material wall, and a heating chamber near a center of the heating chamber. A mold that takes in the supplied powdery raw material (35) and simultaneously heats and pressurizes the current-carrying heating device (36) and the resistance heating device (37) in a pressurized gas atmosphere to form a press-formed material (35 ′). (38), a pressurized gas supply device (39) for supplying a pressurized gas into the furnace body, and an elevating opening / closing device (44) that can freely open and close openings provided at upper and lower portions of a heat insulating material wall of a heating chamber. A cooling fan for cooling the inside of the furnace and circulating a pressurized gas (45)
And a hot press apparatus. 2. An upper and lower pressurizing ram (5) for pressurizing a powdery raw material supplied into a mold.
1, 52), a heating element (53) arranged between the powder material and the pressurizing ram, and a ram energizing device (54) for energizing between the upper and lower pressurizing rams. The hot press apparatus according to claim 1, wherein the hot press is performed. 3. The resistance heating device (37) is a resistance heater (56) surrounding the mold, and heats the mold from the outside by energizing the resistance heater. Hot press equipment. 4. The pressurized gas supply device (39) comprises a blower (57) for supplying pressurized gas into the heating chamber, and a cyclone (58) for sending fresh pressurized gas to the blower. The hot press device according to claim 1, wherein: 5. The lifting / lowering device (44) includes a flange (65, 65) which can be raised and lowered in an opening between the pressure ram and the heat insulating material wall.
The hot press apparatus according to any one of claims 1 to 4, further comprising a hydraulic cylinder (67, 68) attached to the heat insulating material wall and capable of moving the flange up and down. 6. The apparatus according to claim 1, wherein the pressurized gas in the furnace is heat-exchanged by a water-cooled furnace body wall or a heat exchanger.
6. A hot press apparatus according to any one of claims 1 to 5.