Patent GB-190312557-A (GB)
Title: Improvements in and relating to Typewriting Machines
Inventor: ANDERSON NEAL LARKIN
Filed: 1903-06-03
Granted: 1903-11-05
Abstract: 12,557. Anderson, N. L. June 3. Type-writers.-R e l a t e s to motor mechanism for returning the carriage, to means for line spacing at each return of the carriage, and to a paragraphing-stop. Figs. 1 and 2 show the means for returning the carriage. An electric motor in a case A is used to wind up the spring of a drum D, which returns the carriage by rotating a pulley D<3> connected by a band to the carriage. The connection of the band with the carriage is adjustable for regulating the position to which the carriage is returned, and, consequently, the margin. The motor shaft is geared by wheels A<3>, a', A<4> to the shaft B, to which one end of the spring of the drum D is attached. A ratchet-wheel C is fixed on the drum, and is normally engaged by a pawl on a lever F, which prevents it from moving. The edge of the outer flange D of the drum is formed with inclined teeth d engaging similar teeth d' on a ring D' movable on the drum. The other edge of the ring D' is formed with smaller teeth adapted to engage teeth d<3> on the pulley D<3>. The lever F is connected by a rod K to a special key lever K<x>. A pin F<3> on the lever F is adapted to engage in a recess I<5> in a spring-pressed arm I, and hold the pawl out of engagement with the wheel C, after a depression of the key K<x>, until the return of the carriage is completed, when a trip H on the pulley D' engages a pin I<2> on the arm I and releases the lever F. A spring F<4> raises the lever F to engage the pawl and stop the drum. When the wheel C is released, it rotates, and presses the ring D' into engagement with the teeth of the pulley D<3>, and the whole then move together. The motor is stopped and started as follows. On the wheel C is an insulated ring V<3>, in contact with a brush or contact W<3> fixed on the casing A. Another ring U<1> is in contact with a brush W<2> on the casing. The ring U' is carried by an insulating-block U fixed on the shaft B. The brushes W<2>, W<3> are in the motor circuit. A spring pin in the block U, and in contact with the ring U', is pressed out into engagement with the ring V<3>, so that the circuit is closed except when the pin is in contact with one of the blocks W, W<1> of insulating-material let into the ring V<3>. When the wheel C is at rest, the pin is in contact with the piece W<1> and the circuit is broken, and when the wheel is released, it moves the piece W<1> off the pin and closes the circuit. The circuit remains closed until the winding-up of the spring is nearly completed, when the piece W engages the pin and breaks the circuit, checking the speed of the motor. The momentum carries the pin over the block W, when the circuit is again closed until the pin engages the block W<1>, and the motor is then stopped. Fig. 5 shows a means for varying the speed of the motor, and for causing it to start with increased torque. The motor circuit s<7>, s<8> includes a switch lever which may be moved into contact with any one of the pins s<2>, s<3>, s<4>, s<5>, to complete the circuit through more or less of the resistance G. In order to start the motor with the full current, the resistance G, or the greater part of it, is cut out, by a contact s<11> on the lever F engaging a contact s<10>. This closes the motor circuit through the switch lever, conductor s<6>, contacts s'‹, s<11>, pin s<5>, and conductor s<8>. In another arrangement for starting with increased torque when an induction motor is used, Fig. 15, the wires from s<10>, s<11> are connected to the respective wires entering the motor armature, short circuiting the armature when the contacts s<10>, s<11> are closed, and thus converting the motor into an induction motor, but when the contacts s<10>, s<11> are closed, the motor starts as a series motor under increased torque. The line-spacing and paragraphing-stop devices are shown in Figs. 8, 10, 11. On the end of the platen is a ratchet-wheel R engaged by a pawl Z<6> on a:lever Z pivoted in a block L on the carriage. A stop B<8> is adjustably fixed on a rod B pivoted on the framing and held by a spring, so that the stop B<8> is in the pith of the lever Z and operates it to turn the platen as the carriage is returned for a fresh line. In order to return the carriage without line spacing, the rod B is turned by a handle Q to move the stop B<8> down out of the path of the lever Z. If the haudle Q be now released, a projection B<6> on the stop B<8> engages the lever Z and prevents the stop B<8> from engaging this lever, preventing the printing movement of the carriage. In order to stop the return of the carriage in position for commencing a paragraph, the carriage is returned by a lever Z<2> pivoted on the lever Z and held in the position shown in Fig. 11 by a spring. In this position, a lug Z<3> on the lever Z<2> is out of the path of an adjustable stop on the frame, so that the carriage may be returned to its normal initial position. When, however, the carriage is returned by the lever Z<2>, the lug Z<3> is moved down into position to engage the paragraph stop.