| 摘要 |
PURPOSE:To obtain the paper feeding apparatus of a printing machine capable of preventing the generation of jamming, by selectively bringing a desired pinch roller into contact with a platen corresponding to the kind of paper to be used by providing a change-over operation part. CONSTITUTION:The holes 18, 19 for passing a shaft 9 provided to roller arms 11, 13 for holding pinch rollers 10, 12 are equipped with an acute projection 20 and an obtuse projection 21, both of which are engaged with the groove of the shaft 9, at parts of the circumferences thereof. When the shaft 9 is rotated by grasping a lever 22, one side of the projection 21 is pushed to one side of the groove 8 by the first half revolving stroke of the shaft 9 to revolve the arms 13 at both ends and the pinch roller 12 is separated from a platen 2 while one side of the projection 20 is pushed to one side of the groove 8 by the latter half reveloving stroke of said shaft 9 to revolve the central arm 11 and the pinch roller 10 is separated from the platen 2. When printing is performed by using roll paper, only the pinch roller 10 is pressed to the platen 12 and, by this operation, left and right feed irrequlatity is eliminated. When fan folded paper is fed by the platen 2 and a tractor 7 to perform printing, paper is pressed by all of the pinch rollers 10, 12. |
