Patent ID: 6220690
Filing Date: 2001-04-24
Classification: B41J

Abstract:
An ink jet printer having a mechanism to restore at least one nozzle by suction, comprising:nozzle restoring means including a capping, a negative pressure generating means and an air releasing means; whereby a nozzle forming face of said printing head is sealed with a cap when said at least one nozzle is not in use and a printing function of said printing head is restored, with said air releasing means closed, by sucking ink and/or dust from said at least one nozzle by negative pressure applied to a sealed space formed by said printing head and said cap;wherein said negative pressure generating means is used to generate negative pressure to be applied to said sealed space, and said negative pressure generating means and air releasing means are individually driven by a first and a second cam members each having a different phase, which are both mounted on the same cam axis;said air releasing means being used to release said sealed space to the atmosphere, with said air releasing means opened, while ink is being discharged from said at least one nozzle of said printing head at a terminal stage of said suction process by negative pressure;wherein said air releasing means includes a tube, one end of which is communicated with said cap and other end of which is used to release air, a crushing member, used to crush said tube using said second cam member, having a surface eccentric to its axis, to cause movement of the crushing arm when rotated, thereby crushing the tube to cut off air and a receiving member used to support said tube when crushed.