| 摘要 |
PROBLEM TO BE SOLVED: To control the swelling and approach of a painting sheet to a hot plate side by a method in which when the painting sheet position-fixed to a mold is subjected to noncontact heating by a hot plate, at least a part of gas in a mold cavity is discharged outside the cavity, and the gas pressure in the cavity is regulated. SOLUTION: As regards a control valve 52, although a valve which can take two states of opening and closing as a vacuum valve 51 does is applicable, a valve which has a greater pressure loss and a smaller flow rate is used. The pressure loss of a by-pass is made greater than that of a main pipe by the control valve 52 and a side pipe 42. The operation of the control valve 52 is regulated corresponding to the air pressure detected by an air pressure sensor 30 to be controlled to open when the air pressure of a cavity 3 ascends from the vicinity of the atmospheric pressure and to close when the air pressure descends. The pressure loss of the by-pass is increased by the side pipe 42 and the control valve 52, and the by-pass is connected with a vacuum tank 61; however, when the control valve 52 is opened, the discharge of gas in the cavity 3 outside the cavity is made possible by a proper flow rate. |
