Patent SE-314085-B (SE)
Inventor: WUERSCHER H
IPC: B41J29/50
Filed: 1964-01-10
Abstract: 1,074,329. Typewriters &c. SIEMAG FEINMECHANISCHE WERKE G.m.b.H. Dec. 19, 1963 [Jan. 11, 1963; April 19, 1963; July 2, 1963], No. 50217/63. Heading B6F. In a typewriter or like machine wherein a rack 1 on the platen carriage is engaged by a pinion 3, the pinion is alternately locked and released by an electromagnetic clutch device 4a, 4b to allow of letter-spacing movement of the carriage, the energizing and de-energizing of the clutch being controlled by a switching device coupled to the carriage. In one embodiment, Fig. 1, the carriage is moved in letter-spacing direction by the draw band 10 of a spring 11. Mounted on the shaft 2 of the pinion 3 is a disc 13 with inserts 13a of insulating material and engaged by brushes 14a, 14b. Also fixed to the shaft 2 is the armature 4a of an electromagnet 4b, the latter being fixed to a shaft 5 and the parts 4a, 4b constituting a magnetic clutch. The shaft 5 can be driven from a motor 12 through a freewheel device 6 which allows rotation of the shaft 5 in the direction of the arrow 8 only, i.e. in carriage return direction. The motor is stopped during letter spacing and when the carriage has reached its end of line position, the brushes 14a, 14b engage the disc 13 between two insulating inserts, and the winding 4b is energized so that movement in letter spacing direction under the action of spring 11 is inhibited by the device 6. Brief operation of a contact by a key in this carriage position, causes starting of the motor 12 through a relay so that carriage return is effected through parts 4a, 4b, 3, 1. During such movement, the engagement of brushes 14a, 14b with disc 13 is rendered ineffective by the circuitry employed. As the carriage nears its start of line position, it opens a contact and causes the motor to be stopped and clutch 4a, 4b to be released. The carriage moves a short distance under its momentum against the pull of the spring 11 and then starts to move in letter-spacing direction. It then closes a contact which causes the winding 4b to be energized, and the clutch 4a, 4b to engage, whereby the carriage is held in the start of line position. Actuation of a type key or space key now, through relays, causes the clutch 4a, 4b to be released and the carriage to be moved by the spring 11 in letter-spacing direction and the disc 13 to be rotated. When the brushes 14a, 14b next engage a conducting part of the disc 13, a circuit is completed to re-engage the clutch 4a, 4b so as to hold the carriage in the position reached. Operation of a tabulating key causes release of the clutch 4a, 4b and renders the circuit of the brushes 14a, 14b inoperative. The carriage is then moved by the spring 11 until it reaches the required position, whereupon it operates a contact causing the clutch 4a, 4b to become operative once again. Another key is provided whereby tabulation takes place as long as the key is kept depressed. In a second embodiment, Fig. 2, the shaft 2 carries two clutch plates 4a, 16b. The plate 4a engages a friction lining 4c so as to hold the shaft 2 stationary when a winding 4b is energized, and the plate 16b engages a plate 16c on a driven shaft 5 when a winding 16a is energized. A motor driving the shaft 5 rotates continuously and is reversible, but normally rotates in a direction which would move the shaft 2 in letter-spacing direction. When the carriage reaches the end of a line, the brushes 14a, 14b engage a conducting part of the disc 13, and the winding 4b is energized so that the shaft 2 and carriage are held stationary. Upon actuation of a carriage-return key contacts are closed and through a relay system causes winding 4b to be de-energized, the motor to be reversed, the winding 16a energized, and the circuit of the brushes rendered inoperative. Near the end of the carriage return movement, a contact is opened and through the circuitry causes winding 4b to be energized to brake the carriage movement and the motor to be reversed. A small forward movement of the carriage now takes place, whereupon a contact is operated by the carriage to cause the winding 16a to be de-energized and the carriage brought to rest at the beginning of a line. Depression of a typekey or space-bar causes the winding 4b to be de-energized and winding 16a to be energized so that the carriage is driven forward by the motor. At the end of a letter-spacing movement, the brushes engage another conducting sector of the disc 13 and cause winding 4b to be energized and winding 16a de-energized so that the carriage comes to rest. Actuation of a tabulating key causes the shaft 2 to be coupled to the shaft 5 by the clutch devices 16a, 16b, 16c, the brake device 4a, 4b to be released, and the brushes 14a, 14b rendered inoperative. When the carriage reaches a position about one and a half spaces before the required column position, a contact is changed over to cause release of the clutch 16a . . . 16c and to render the brake device 4a, 4b and brushes operative. When the brushes now contact a conductive part of the disc 13, the device 16a ... 16c is again rendered operative and the device 14a, 14b rendered inoperative to move the carriage through one space to the required column position where the brushes engage a further conductive part of the disc 13 and cause the devices 16a ... 16c and 14a, 14b to be again reversed so that the carriage is held at the column position. Reverse tabulation can be effected by a key which causes reversal of the motor. Control of the backward movement is effected as for forward tabulation except that the carriage is caused to move two or three spaces beyond the required position and is then moved forward to that position. Variable spacing.-More than one disc 13 may be mounted on the shaft, the insulated inserts on each disc being differently spaced from those on the others so as to effect different letter spacings. The discs 13 are mounted on the shaft 2 by means of springs 25, Fig. 5 (not shown), forming a drive which can slip and all except the one in use are held stationary by latches 34 ... 36. By providing additional discs 13, a carriage spacing movement corresponding to each individual character may be obtained. Instead of a disc 13 with insulating inserts, a slotted disc and a photo-cell may be employed to provide the pulses required to control the carriage movement.