T. A. EDISON.

Improvement in Electrical Printing-Machines.

Patented Nov. 12, 1872.

AM. PHOTO-1117106! PHIG 611M )1 (DSBOHNES P505555.)

UNITED TATES THOMAS A. EDISON, OF NEWARK, NEW JERSEY, ASSIGNOR TO HIMSELF AND GEORGE HARRINGTON, OF WASHINGTON, DISTRICT OF COLUMBIA.

IMPROVEMENT IN ELECTRICAL PRINTING-MACHINES.

Specification forming part of Letters Patent No. 133,019, dated November 12 1872.

thereof.

This invention is intended for printing upon a strip or sheet of paper by a type-wheel, so

that messages, instead of being written, can be printed off by touching finger-keys. The machine is also available for printing copies of documents or composing and printing instead of writing.

I make use of a type-wheel upon a shaft that also carries an armature and circuit-breaker that is driven by a magnetic motor, the said armature propelling the said shaft by frictional contact. Upon the shaft is an arm that is stopped by one of a range of keys, these being positioned so that the type-wheel, with the corresponding type, will be stopped at the position to be impressed. The depression of the fingerkey completes a circuit to a magnet that gives the impression.

In the drawing, Figure l is a general plan of the machine and Fig.2 is an elevation, partially in section, of the same.

The type-wheel a is upon a shaft, 12, in suitable bearings in the bed 0 and frame d. Affixed to this shaft 12 are also the arm or arms (1 and the armature f and circuit-breaker e to the springs g; and this armature and circuit-breaker are connected to the shaft by a frictioncoupling, so that they can easily revolve the shaft when free but when the shaft is stopped the armature will continue to revolve. The electro-ma-gnets h and the connections from the battery It to form, with the armature f, an electro-motor are known, and do not require further description. The finger-keys l are arranged so as to move a projection, '5, to each key into the path of the arm d, so as to arrest the movement of the arm and type-wheel when the former comes into contact with the projection i of the depressed key. These projections i are arranged circularly, and, if positioned in a circle, then only one arm, d, will be required. If positioned in a half circle, they must be in two rows, one above the other, and two arms, 61, will be required, as shown. The printing. lever on is on a fulcrum, n, and is operated upon by the magnet 19, the connection for this magnet from the battery q being completed by the depression of the finger-key, causing the slide-rod of said key to stop upon the insulated plate 8, one pole of the battery being connected therewith by the wire or wires 7, and the other, by the wire 8, to the magnet 9; and from the latter there is a connection, 3, to the metallic plate 3 carrying the keys 1. The impressionlever is made with any suitable feeding device for moving a strip of paper along or presenting a sheet, line after line, to the type-wheel.

It will now be understood that the magnetic motor maintains a rapid rotation of the type-wheel until one of the keys is depressed, which arrests, by its projection z, the arm (1 and type-wheel, the latter having a corresponding letter opposite the impression-pad, and instantly the impression is given by the action of the elect-ro-magnet p.

A stop-pawl, r, prevents any risk of rebound when the arm is arrested by the stop 1'.

I claim as my invention- 1. The type-wheel and shaft, revolved by friction from the armature of an electromotor placed upon the type-wheel shaft, substantially as set forth.

2. The finger-keys Z and electro-magnet p, connected as set forth, in combination with said type-wheel and the impression-lever, substantially as specified.

Signed by me this 18th day of April, 1872.

T. A. EDISON. Witnesses:

Gem. '1. PINGKNEY, CHAS. H. SMITH.