Method of forming carbon-fiber product and implementation device thereof

A carbon-fiber product forming method implemented by a carbon-fiber product forming device including

• a first chamber including a hollow cavity and a first entire wall enclosing the hollow cavity;
• at least two hot-pressing plates disposed inside the hollow cavity with each of the hot-pressing plates being formed with a plurality of through holes being connected to a plurality of conduits, respectively;
• a mold including a male mold, a female mold, and a mold cavity being formed between the male mold and the female mold and with an outward opening, the mold being disposed on one of the hot-pressing plates and between the hot-pressing plates;
• an air bag disposed inside the mold cavity with the air bag including a bag opening disposed near the outward opening, the air bag swelling to have the same shape as that of a carbon-fiber product to be produced when the inside of the air bag is fulfilled with air;
• and
• a second chamber formed with an accommodating room to include at least one barometric pipe and with a second entire wall enclosing the accommodating room, the accommodating room being in mutual communication with the hollow cavity, the second entire wall of the second chamber being disposed with an air extracting port, a barometric port, a switchable air inlet port, and a switchable heat medium entry port, the air extracting port being connected to a vacuum pump, one end of the barometric pipe being connected to the barometric port while the other end of the barometric pipe being connected to the outward opening, the barometric port being connected to an air source, the air inlet port being exposed to atmosphere when switched on, one side of the heat medium entry port being connected to the conduits while the other side of the heat medium entry port being connected to a heat medium source;
• wherein an outer surface of the air bag is to be attached with a plurality of carbon-fiber composite layers;
• a heat medium from the heat medium source is to be injected into the inside of the hot-pressing plates via the heat medium entry port, the conduits, and the through holes to enable the mold to have various temperature ranges starting from room temperature and including the glass transition temperature of the carbon-fiber composite layers;
• air inside the hollow cavity is to be extracted by the vacuum pump via the air extracting port;
• air coming from the air source is to be periodically conducted into the air bag via the barometric port, the barometric pipe, the outward opening, and the bag opening when the temperature of the mold starts to increase from the room temperature to the glass transition temperature of the carbon-fiber composite layers;
• a cycle frequency of periodically conducting air into the air bag varies as the temperature ranges within which the mold is changes;
• and the cycle frequency of periodically conducting air into the air bag decreases as the air pressure inside the hollow cavity decreases,
• the method comprising:
• controlling the air pressure inside the hollow cavity to be near 0.01 atm, controlling the cycle frequency of periodically conducting air into the air bag to be zero, and controlling the air pressure inside the air bag to be between 5 kgf/cm2 to 20 kgf/cm2 when the temperature of the mold increases from 110 degrees Celsius to 150 degrees Celsius;
• and
• replacing the heat medium with a coolant of a temperature 10 degrees lower than that of the heat medium and injecting the coolant to the inside of the hot-pressing plates to cool down the mold.