GB564301A - Improvements in or relating to platen rolls for writing or imprinting apparatus - Google Patents

Abstract

564,301. Typewriters. WILLIAMS, W. P. (Standard Register Co.). June 21, 1943, No. 10002. [Class 100 (iv)] The platen roll 1 of a typewriter or like machine is constructed so that the feed pins 12 of either of two or more sets of pins can be rendered inoperative so as to permit the sheets to be fed by roller feed, and the arrangement permits sheets of different widths to be fed positively by permitting the required pair of pin wheels 12 to remain operative while the other wheel or wheels is controlled so that the pins are not projected for operation at the required position, as shown in Fig. 3, but are projected later in the period of rotation of the platen so that they fail to engage the feed perforations. The cams 14, Fig. 6 (not shown), which operate to project the feed pins in known manner, are secured to discs 16 which are each adjustably held in fixed position by means of a screw 25 engaging one of a series of holes 17 in each disc. A mask or bridging device 31 is detachably secured to a head 20 on the arm 19 of a collar 18 loosely mounted on the hub 15, and is brought into position for continuing the writing surface of the platen roll 1 across the position of each positive pin feed device when the latter is rendered inoperative. The cams can be operated to trip the pin feeds by mechanism similar to that described in Specification 408,125, comprising a bar 28 engaging a bifurcated arm 27 on a collar 26 fitted with a spring-pressed pawl 29 which can engage either of two notches 23, 23a in a collar 22 provided with an arcuate slot 24 through which the screw 25 passes. The bridging device 31 can be adjusted to a slight extent relatively to the associated cam so that different portions of its face may be brought into the actual writing-line to allow for wear.