Wire-dot printer in which printing modes can be changed over from one to

Abstract

Printing wires are able to be changed over from one to another by the movement of a printing head alone, thereby eliminating the need for a solenoid and simplifying the arrangement. The printing quality is improved by uniformly guiding the printing wires with the entire circumference of each guide hole, and further the amount of torsion of the printing wires caused by changeover of the printing wire arrangements is equalized, thereby stabilizing the printing characteristics and eliminating the difference in the printing characteristics between the parallel and staggered arrangements and also improving the durability. A first front guide is secured to a nose portion of a head frame. A front guide supporting frame, which supports a second front guide, is provided on the nose portion of the head frame so that the frame is movable in the direction of alignment of the printing wires. The printing wires are guided by the second front guide and the first front guide. The head frame is provided with a sliding member and a transmission-changeover means which causes the front guide supporting frame to be displaced in response to displacement of the sliding member. When the printing head is moved beyond the normal travel region, the sliding member abuts against a stationary member in the printer and is thereby displaced. The transmission-changeover means causes the front guide supporting frame to be displaced in response to the displacement of the sliding member, thereby moving the second front guide, and thus changing over the staggered and parallel arrangements from one to the other.