Patent ID: 7083681

Claim:
A unit for forming a coating film on an internal surface of an elongated tube comprising: a holder for longitudinally holding an elongated tube; a first pump for flowing through the elongated tube a coating solution containing a solvent whose viscosity is to be reduced by heating, so that the coating solution is applied to the internal surface of the elongated tube; a first heat source for heating the coating solution applied to the internal surface of the elongated tube; a slider for moving the heat source along the elongated tube from an upper side to a lower side thereof sequentially, so that the coating solution in the elongated tube can be dried while heating the elongated tube from the upper side to the lower side thereof sequentially; a controller for controlling the moving rate of the slider, while the heat source is moved along the elongated tube from the upper side to the lower side thereof sequentially, to adjust the moving rate of heat source so that a through-hole in the elongated tube is clogged with the coating solution whose viscosity is reduced by heating using the heat source; and a second pump for exerting suction through the through-hole from the lower side of the elongated tube so that a clogged portion of the through-hole moves downwards.