History of the Typewriter

Forfatter: Geo. Carl Mares

År: 1909

Forlag: Guilbert Pitman

Sted: London

Sider: 318

Søgning i bogen

Den bedste måde at søge i bogen er ved at downloade PDF'en og søge i den.

Derved får du fremhævet ordene visuelt direkte på billedet af siden.

Download PDF

Digitaliseret bog

Bogens tekst er maskinlæst, så der kan være en del fejl og mangler.

Side af 333 Forrige Næste
— 39 — Fig. 27 strikes against the face of the several types the instant they are brought within its range, a sheet of carbonized paper, held in contact with a sheet of writing paper, being suspended between the hammer and the type-wheel. Transparent transfer paper may be also employed as well to enable the operator to see the progress of the writing as to preserve a copy. The hammer is operated by an oscillating bar, A, with which it is connected by a small rod, N, hinged to its butt. This rod has on its lower end a catch, which engages an arm projecting from the oscillating bar, A, and, having an eccentric movement, it causes it to act in a manner somewhat analogous to the hopper of a piano. The depression of a key lowers this eccentric arm, and retracts the rod of the hammer. Just as the key has been carried through to its full movement, and the corresponding type brought to a proper position, the catch is pushed off the eccentric and the hammer is impelled against the type by a spring, 0. When the key is released the arm of the oscillating bar engages the catch, and the hammer is ready for a new stroke. It is, however, neces- sary by this arrangement to release one key before striking another ; and it is this necessity that limits the rapidity of the instrument, which otherwise might have struck of' printed characters as fast as the piano can yield consecutive notes. “ Third, now for the feed of the paper. A square open frame, P, which for distinction may be termed the page- frame, slides in vertical grooves formed in the upright part of the case, in the plane of the type-wheel. Within this,