Carpet ink-jet decorating machine having thickness detecting apparatus

The utility model relates to a carpet ink-jet printing machine with a thickness detection device, comprising a conveyor belt frame, a conveyor belt, a nozzle support, a solenoid valve nozzle and a contact sensor. The utility model is characterized in that: the conveyor belt is arranged on the conveyor belt frame, and the solenoid valve nozzle is arranged on the nozzle support; the contact sensor is arranged on a height detection support, and the height detection support is arranged above the conveyor belt frame; a lifting pair, connected with the two sides of the conveyor belt frame, is arranged at the both ends of the height detection support, and the contact sensor controls the lifting of the lifting pair; a height sensor is arranged on the height detection support and sends signals showing the thickness of the printing medium. The utility model has the advantages of automatically adjusting the distance between the nozzle and the printing medium according to the height of the printing medium, producing patterns with high precision, increasing productivity and simultaneously avoiding the waste caused by imprecise printing of printing medium patterns and blanking out.