GB470575A - Improvements in or relating to typewriters and like machines - Google Patents

Abstract

470,575. Typewriters &c. STANDARD REGISTER CO., and SHERMAN, J. Q. Feb. 17, 1936, No. 4846. [Class 100 (iv)] Line - spacing mechanism.-A platen or feed-roller is connected by a slip-coupling to line-spacing mechanism for normal spacing, and, for feeding headings or blanks past the printing line, is provided with auxiliary mechanism, which is arranged to impart a full movement to the line-spacing mechanism and then to impart a further movement to the platen or feed-roller, the line-spacing mechanism remaining stationary so that correct normal spacing can be effected thereby when again operated. The platen 2, Fig. 1, is provided with normal and auxiliary line-spacing mechanisms operated by levers 15, 15<1> which are interconnected by means of relatively slidable links 28 and an interposed spring 29, so arranged that the lever 15 can be operated independently of the lever 15<1>. The normal spacing-mechanism comprises the usual slide 7 carrying a pawl 5 co-operating with a ratchet-wheel 4, a finger 8 on the pawl co-operating with a fixed backstop, and a shelf which is adjustable to regulate the spacing. The ratchet-wheel is frictionally coupled to the platen by means of a spring- urged cone 21. The auxiliary spacing-mechanism comprises a slide 7<1>, pawl 5<1>, an adjustable shelf 9<1>, a ratchet-wheel 4<1> secured to the platen-shaft 3, and a pawl back-stop 18<1> which is slidably mounted and is adjustable by means of a threaded rod 26 provided with a knob 27. Alternatively, the back-stop may consist of an eccentric adjustable by means of a fingerpiece. Normally, the lever 15 is employed for line-spacing, and the link 28 connected thereto slides idly on the other link. After a form has been typed, the lever 15<1> is employed for line-spacing, the links 28 causing the lever 15 also to be operated. After the pawl 5 has been jammed by the back-stop, the coupling 21 slips, and a further line-spacing movement, limited by the adjustable back-stop 181, is effected by means of the pawl 5<1>. The ratchetwheel 4 remains in register with the pawl 5 so that correct normal spacing is effected when the lever 15 is again operated independently. The mechanism shown at the lefthand of Fig. 1 may be replaced by that shown in Figs. 5 and 6, and comprising a ratchetwheel 4 for normal spacing, and a slightly smaller ratchet-wheel 34 for auxiliary spacing, the ratchet-wheels co-operating with separate pawls 5 carried by a single slide 7. The ratchet-wheel 4 is connected to the platen by means of a friction-coupling 21, and the ratchet-wheel 34 has a slot 35 which engages a pin 36 on the platen. During normal spacing, the pin travels idly in the slot, but after a number of spacing movements, determined by the length of the slot, the rear end of the slot engages the pin, and increased spacing is effected by the ratchet-wheel 34, the frictioncoupling permitting the ratchet-wheel 4 to slip.