摘要:
A shuttle printer carries out printing on a printing paper when a hammer bank shuttles back and fourth. At the beginning of the hammer bank reversal at the right or left end in the hammer bank shuttling path, a braking force is exerted to a shuttle motor which drives the hammer bank and an acceleration force is exerted to the shuttle motor immediately after the hammer bank turns around. In order to set a reversing duration of the hammer bank at constant, the braking force and the acceleration force exerting durations are prolonged from a predetermined minimum to a value when the hammer bank reversing duration is shortened to an extent as desired, whereby a printing paper can be fed a predetermined amount within the hammer bank reversing duration as desired.
摘要:
In a dot matrix line printer, a pair of pin tractors for feeding a print paper are operatively connected to a paper feed motor, and a tension roller mechanism disposed beneath a platen is operatively connected to a separately provided drive motor. To eliminate a paper slack which may occur when the feeding of the print paper is stopped after creating many blank lines, the drive motor is energized for a short period of time immediately before the paper feeding is ended. The tension roller mechanism which is made up of a plurality of rollers pulls the print paper in a direction opposite the paper feeding direction to thus prevent the print paper from slackening.
摘要:
A dot line printer provided with an ordinary dot density printing mode, a low dot density or draft printing mode and a high dot density printing mode. A hammer bank provided with a plurality of printing hammers is reciprocally movable in a shuttling direction for dot impressions when the hammer bank is moved through a printing region, and the moving direction of the hammer bank is reversed at a reversing region where a printing sheet is fed in a line to line direction. A shuttle cam is provided which is drivingly connected to the hammer bank. The shuttle cam has a cam profile capable of providing a cam lift characteristic approximately intermediate between a cam lift characteristics of the ordinary printing mode and that of the low dot density printing mode. A shuttling velocity of the hammer bank is changed in accordance with the selected printing mode and position of the hammer bank.