Patent GB-191024215-A (GB)
Title: Improvements in or relating to Calculating Machines, Cash Registers and the like.
Inventor: CLARKE EDWARD RUSSELL
IPC: B41J9/14
Filed: 1910-10-19
Granted: 1911-10-19
Abstract: 24,215. Clarke, E. R. Oct. 19. Roller - impression arrangements for line-printing machines. In arrangements for use in cash - registers &c. wherein an impression roller is traversed over the types from end to end of the line, the pressure of the roller is automatically controlled in such a manner that the printing of redundant symbols, for example noughts to the left of the first significant figure, is prevented; further, the roller is mounted so as to compensate for inequalities in level of the types in the line. In the arrangement shown, the impression roller C is journaled on an arm D secured to a rod E forming part of a carriage which can be traversed to the right by a pull-tape S, and is connected to a returning-spring T. The roller may be rotated frictionally, or positive gearing may be employed. The rod E is mounted in bearings F. and is connected by straps M, M<1> to a rod K, which is mounted in bearings L, the straps permitting independent rotation of the rods. The roller is arranged over a series of printing-members, such as type-sectors A, and is normally held raised by a detent J which is secured to the rod E and engages as by a notch J<1> with a lug Q on the rod K, a tensionspring R being arranged between the detent and the rod K. The detent is controlled by a tappet P pivoted on a sleeve O<1>, which is mounted to travel with the rod K, but is held against rotation by a link O<2>, engaging a fixed rod O<3>. The foot of the tappet engages a lateral finger N' on a collar N secured to the rod K, and the head of the tappet is arranged to engage any of the type-sectors which have been projected from the zero position. In operation, the roller C is held raised until the tappet P engages the first type-sector that has been set to print a significant figure, whereupon, by engagement of the tappet with the finger N<1>, the rod K is rocked to carry the lug Q clear of the detent J. The detent, thus released, is drawn downwards by the spring R, and rotates the rod E to bring the roller C on to the type-sectors, thereby printing the first significant figure on the paper V through an ink-ribbon U. The roller is held down by the spring until the last type-sector is passed, whereupon a rear extension D<1> of the arm D engages a projection H, which lifts the roller clear of the paper and permits the spring R and a spring engaging lateral arms P<2> on the tappet to restore the controlling-devices to the initial position. During the return of the roller, the tappet is tripped idly by the projected typesectors; or these may be arranged to be restored before the roller is returned. The impression roller may be arranged to print while travelling from right to left, and the roller may be mounted so that its normal tendency is to move away from the types. To compensate for inequalities in the level of the types the roller is mounted loosely on the arm D, the mounting preferably being such that the roller has vertical but not lateral freedom. The mounting may consist of a sleeve which carries the roller and is secured to the arm D by a screw formed with a rounded shoulder and with flats which engage cheeks inside the sleeve.