Abstract: A drum-changeable device for a printer comprises a plurality of drums and a switch device. The drums are disposed under the work surface of a printer. Each drum has a plurality of protrusions covered by the same kind of material and the protrusions of different drum are covered by different kinds of material for moving forward printing articles of different kinds of material. The switch device is connected with the drums for moving a suitable drum toward the work surface of the printer according to the kinds of material of the printing articles.

Abstract: A height-adjusting foolproof apparatus for a printing module used in a large ink-jet printer comprises a first adjusting member in connection with a printing module for moving the printing module vertically and a second adjusting member in connection with the large ink-jet printer for presetting the height of the printing module according to the thickness or hardness of a material. After the second adjusting member is adjusted to the position of the preset height, the first adjusting member together with the printing module are leveled downward until the first adjusting member is against a protrusion of the second adjusting member, so that the printing module is pulled at the preset height.

Abstract: A printing module for use in a large ink-jet printer includes a frame and an ink-jet unit secured to the frame. The ink-jet unit has a group of ink cartridges to emit droplets of ink onto a media to be printed. At least one irradiator is disposed at a side of the frame for casting a beam of ultraviolet light downward to irradiate and dry the droplets of ink emitted on the media, and means is provided for adjusting the position of the irradiator in forward and backward directions with respect to the frame. The printing module can be used in the large ink-jet printer to produce a sharp print.

Abstract: An adjusting device for adjusting printing heads of inkjet printing machine includes a base connected to a printing unit and a plurality of printing assemblies are respectively connected to the base. Each printing assembly has a printing head connected thereto and a connection board is connected to an end wall of each printing assembly. Three adjusting members extend through the end board and contact against the end wall, and the three adjusting members are located at three peaks of an imaginary right triangle on the end board so as to adjust the printing head in different directions. A fourth adjusting member extends through the end board and is fixed to the end wall. The fourth adjusting member is located at a center of weight of the imaginary right triangle.

Abstract: A printing device for inkjet printing machine includes a base having a printing unit connected thereto and the printing unit includes a plurality of printing heads and ink cartridges. An UV beam generating device is connected to a side of the base and has an aperture defined in an underside thereof so that the UV beams goes through the aperture and toward an object to be printed. An anti-scattering device is connected between the printing heads and the aperture so as to keep the UV beams away from the nozzles of the printing heads.