JPH067665A - Method for controlling gas current of autoclave - Google Patents

Abstract

PURPOSE:To eliminate the temp. difference between the recessed part or shaded part of a formed article of intricate shape and the other parts and to obtain a high-quality formed article by circulating a gas through an outer passage and a duct properly backward and forward. CONSTITUTION:The pressure vessel A of an autoclave is provided with a door 2a, a gas duct 6a, an outer gas passage 6b formed between the vessel wall and gas duct wall and an axial fan 22. A forming material 1 is placed in the vessel which is then closed by the door and pressurized, heated and formed. In this case, a temp. control means H is provided, the control means is operated to drive the fan 22 properly forward or backward, and the gas is circulated forward or backward through the passage 6b and duct 6a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a fiber reinforced plastic (FR) used for aircraft, space equipment, industrial equipment and the like.
The present invention relates to a method for controlling a gas flow when a molding material such as a laminated structure or a component of P), a multilayer printed wiring board used as an electronic device component, or a composite material for building materials is molded in an autoclave.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Laid-Open No. 2-14730 is known as a technique for controlling the gas flow in an autoclave.

[0003] This technique, as shown in FIG.
In an autoclave in which a molding material 1 is heated under pressure in a pressure vessel A which is provided with a wind tunnel 6a in which a gas is circulated by a blower turbo fan 22a. The gas flow flowing out from the outer ventilation passage 6b formed between the wall 5 and the wall 5 is turned into a swirl flow by the guide vanes 30, and then the inner wall 2b of the door facing the swirl flow is faced.
The reverse flow is made to flow in one direction while swirling in the wind tunnel 6a.

[0004]

However, according to this technique, since gas flows so as to wrap around the entire molding material in the wind tunnel, the cavity generated in the wind tunnel from the end part of the external ventilation passage is extremely small, and the wind in each part of the wind tunnel is small. It has the advantage that the velocity distribution can be made uniform, and that the wind passes through the shadow of the molding material to a certain extent due to the swirling flow, and the molding material can be heated more uniformly than the entire surface. On the other hand, when the shadow portion of the molding material has a complicated shape, for example, when the molding material has dents or irregularities as shown in FIGS. 1 and 2, the gas does not reach, that is, the shadow portion is formed, As a result, a temperature difference occurs between the recessed portion or the shaded portion and the other portion, which adversely affects the formability, and a solution to this is awaited.

The present invention was developed for the purpose of solving the above-mentioned problems.

[0006]

According to the present invention, as shown in FIG. 1, a molding material 1 is housed and provided so as to be hermetically sealed by a door 2a, and a gas is circulated by a fan between a container inner wall and a wind tunnel wall. In an autoclave in which a molding material 1 is heated under pressure in a pressure vessel A provided with the formed external ventilation passage 6b and a wind tunnel 6a, the fan serves as an axial flow fan 22 and a temperature control means H is provided. The control means is actuated to appropriately rotate the fan 22 in the forward and reverse directions, and the external ventilation passage 6b
The temperature of the molding material front portion 32 and the molding material back recessed portion 3 are controlled by appropriately flowing the gas flowing in the wind tunnel 6a in the forward and reverse directions.
The temperature of 3 is set to be substantially the same.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, an example of an autoclave molding apparatus for carrying out the present invention will be described. Autoclave molding equipment
As shown in FIGS. 1 and 2, a door 2a for accommodating and sealing the molding material 1 in a container 2, an outer ventilation passage 6b formed between an inner wall of the container for circulating gas and a wind tunnel wall, and a wind tunnel 6a are provided. A pressure vessel A provided, a pressurizing means B for supplying a high-pressure gas into the pressure vessel A to pressurize the molding material 1, and a heating / cooling means C for heating and cooling the high-pressure gas supplied in the pressure vessel A. And a decompression means D for decompressing the inside of the vacuum bag 18 that seals the molding material 1 to a high vacuum, and a gas that circulates the heated or cooled gas by the fan 22 and circulates in the outside ventilation passage 6b and the wind tunnel 6a. The fan control means E is configured to control the above flow so as to appropriately flow in the forward and reverse directions.

Next, the details of each means will be described. As shown in FIGS. 1 and 2, the pressure vessel A has a container body 2
A door 2a for sealing is provided in the container main body 2, and a rail 4 for guiding the carriage 3 is laid inside the container main body 2, and a double ventilation passage (outside the outside) is formed along the inner wall of the container main body 2 by a cylindrical thin plate wind tunnel wall 5. The air passage 6b and the wind tunnel 6a) are formed.

As shown in FIG. 1, the pressurizing means B is provided so that gas such as high pressure nitrogen gas, high pressure carbon dioxide gas, high pressure air, etc. can be supplied from the high pressure gas supply source 7 through the automatic valve 8. The gas is heated or cooled via the heater 10 and the heat exchanger 11. Then, it is exhausted through the automatic valve 9.

The heating / cooling means C is provided with a second carriage 12 on which a heater 10 and a heat exchanger 11 (used as a cooler in this case) are mounted on a rail 4 at the rear of the pressure vessel A,
The gas body is heated or cooled by the heater 10 and the heat exchanger 11. Then, the pressure vessel is penetrated through the automatic valve 13 to communicate with the heat exchanger 11 to supply cooling water, and the lower portion of the pressure vessel A is communicated from below the heat exchanger 11 and is cooled via the automatic valve 14. It is provided so that the used water can be discharged. As another example of the heating / cooling means, a heating medium is heated and cooled outside the pressure vessel, and the heating medium is heated through a heat exchanger to heat a gas body,
It may be cooled and is not limited to the embodiment of the present invention.

The depressurizing means D, as shown in FIGS.
A vacuum pump 15 installed outside the pressure vessel A communicates with the inside of the pressure vessel A through an automatic valve 16 and is piped. At the tip of the pipe, as shown in FIG. The vacuum joint is detachably attached to the vacuum joint 17b which is airtightly held and joined via a jig 19 which is communicated from the inside of the vacuum bag 18. Then, by operating the vacuum pump 15, the inside of the vacuum bag 18 in which the molding material 1 is covered and sealed is decompressed via the automatic valve 16 to a high vacuum.

As shown in FIGS. 1 and 2, the fan control means E is provided with a small container (small pressure container) 21 in which a motor 20 is incorporated in the rear part of the pressure container A in a sealable manner, and the inside of the rear part of the pressure container A. Fan drive means F comprising a fan 22 fitted and fixed to a motor shaft 20a which is projected to
The temperature detector 23 for detecting the temperature of the gas in the small container 21 and the detection signal thereof are transmitted to the automatic valve 24 to transmit the small container 2
The temperature at which the motor cooling means G that cools and controls the motor 20 in 1 to a temperature below the permissible temperature and the fan 22 of the fan driving means are normally and reversely rotated and the gas flow is appropriately reversed in the axial direction to contact the molding material 1. And temperature control means H for controlling the temperature. The fan used here is an axial-flow fan capable of discharging and sucking gas in the axial direction by reversing the rotation direction of the motor. Also,
As another embodiment of the fan driving means, as shown in FIG. 5, a motor 20 is installed at a rear outer position of the pressure vessel A,
The shaft portion of the motor is projected into the pressure vessel A through the sealing mechanism 34, and the fan 22a for blowing air is attached to the tip portion of the shaft of the motor.
The motor 20 may be fitted and fixed, and the motor 20 may be an inverter or the like capable of speed conversion, and is not limited to the embodiment of the present invention.

As shown in FIG. 3, the temperature control means H controls the temperature of the molding material surface portion and the temperature of the molding material back recess portion by the controller 28 by comparing and adjusting the temperature detector 26 and the temperature detector 27. 20 is operated and the fan 22 is rotated, and the flow of gas is alternately controlled so that the temperatures of the two become substantially the same. If the shape of the molding material is relatively simple, for example, the circuit can be simplified by programming the forward / reverse rotation time of the motor based on an empirical value, and the circuit differs depending on the molding material. Not done.

Further, the guide vanes 30 provided in the outer ventilation passage 6b
Is an external ventilation passage 6 formed between the inner wall of the container and the wind tunnel wall 5.
The gas flow flowing out from the end b is a swirl flow, and as shown in FIGS. 1 and 2, a large number of gas flows are provided in the entire circumference of the outflow portion of the external ventilation passage 6b. Then, after the gas flow flowing out from the outer ventilation passage 6b is made into a swirling flow by the guide vanes 30, it is reversed by the door inner wall 2b facing this so that the reverse flow swirls in the wind tunnel 6a and flows in one direction. It is composed. In the embodiment of the present invention, the guide vanes are provided in the external ventilation passage, but the present invention can be implemented without providing the guide vanes, for example, and the present invention is not limited thereto.

Next, the operation will be described. First, in the preparation stage, the molding material 1 is housed in the pressure container A shown in FIGS. 1 and 2, and the decompression means D decompresses the inside of the vacuum bag 18 to complete the preparation for molding.

Next, the pressurizing means B shown in FIGS. 1 and 2 is operated to supply the high-pressure gas into the pressure vessel A, and the fan driving means F is operated to remove the high-pressure gas by the solid line in FIG. As shown by the arrow, after the gas flow passing through the outer ventilation passage 6b and flowing out from the outer ventilation passage is made into a swirling flow by the guide vanes 30, it is reversed by the door inner wall 2b facing this, and the reversal flow is the wind tunnel. It circulates in the pressure vessel A while turning in 6a. Then, when the temperature difference between the molding material back recess 33 and the molding material surface portion 32 becomes larger than the set value by the temperature control means H, a signal is sent to the motor to rotate the motor in the reverse direction, the fan 22 rotates in the reverse direction, and the gas is discharged. As shown by the chain line arrow in FIG. 1, the air flows through the wind tunnel 6a, is inverted by the inner wall 2b of the door, flows in the opposite direction through the outer ventilation passage 6b, and is sucked into the fan 22. Then, the gas circulates into the wind tunnel 6a via the heater 10 and the heat exchanger 11. While appropriately converting such a gas flow, molding is performed by heating under pressure according to a molding pattern as shown in FIG. By appropriately changing the gas flow in this manner, the gas flowing while swirling in the wind tunnel 6a by the guide vanes 30 has a complicated shape back recess 33 of the molding material.
Even if the molding material does not flow into the molding material, the molding material can be brought into contact with the recess 33 in the back of the molding material in a reverse direction, and the flow of the gas acts alternately. It can be heated.

Next, when entering the cooling stage, the pressure is reduced and cooled according to the molding pattern as shown in FIG.
Like the heating, the gas flows are made to alternately act, and the molding material 1 is cooled to complete the molding. Next, the door 2a is opened and the molding material 1 is carried out to complete one step.

[0018]

Since the present invention is configured as described above, the temperature of the molding material can be controlled by reversing the flow of gas as appropriate, so that the temperature of the molding material surface and the temperature of the molding material back recess are substantially the same. Therefore, the adverse effect of the moldability due to the temperature difference that has conventionally occurred between the recessed portion or the shaded portion and the other portion of the complicated molded product is eliminated, and a high quality molded product can be obtained.

[Brief description of drawings]

FIG. 1 is a partially cutaway schematic side view of an autoclave molding apparatus for carrying out the present invention.

FIG. 2 is a schematic front view of the autoclave molding apparatus as viewed in the direction of arrow XX in FIG.

FIG. 3 shows a block diagram of a temperature control means embodying the present invention.

FIG. 4 shows an example of a molding pattern of an autoclave for carrying out the present invention.

FIG. 5 is a partially cutaway schematic side view showing an embodiment of a technique for controlling a gas flow in a conventional autoclave.

[Explanation of symbols]

 A pressure vessel B pressurizing means C heating / cooling means D depressurizing means E fan control means F fan driving means G motor cooling means H temperature control means 1 molding material 2 container body 2a door 2b door inner wall 3 trolley 4 rail 5 wind tunnel wall 6a wind tunnel 6b Outside ventilation passage 7 High-pressure gas supply source 8 Automatic valve 9 Automatic valve 10 Heater 11 Heat exchanger 12 Second trolley 13 Automatic valve 14 Automatic valve 15 Vacuum pump 16 Automatic valve 17a Vacuum joint 17b Vacuum joint 18 Vacuum bag 19 Jig 20 Motor 20a Motor shaft 21 Small container 22 Fan 22a Fan 23 Temperature detector 24 Automatic valve 26 Temperature detector 27 Temperature detector 28 Controller 30 Guide vane 32 Molding material front part 33 Molding material back recess 34 Sealing mechanism

Claims (1)

[Claims] 1. A molding material in a pressure container having an air passage and an outer ventilation passage formed between an inner wall of a container and a wind tunnel wall in which the molding material is housed so as to be hermetically sealed by a door and a fan circulates gas. In an autoclave for heating and molding under pressure, the fan is an axial flow fan and temperature control means is provided, and the temperature control means is actuated to rotate the fan forward and backward as appropriate, so that the external ventilation passage and the wind tunnel are A method for controlling gas flow in an autoclave, characterized in that the circulating gas flow is controlled so as to flow in forward and reverse directions as appropriate.