Patent GB-567654-A (GB)
Title: Improvements in and relating to typewriting machines
IPC: B41J19/64
Filed: 1943-05-20
Abstract: 567,654. Typewriters. COLTON, A. F., and COXHEAD CORPORATION, R. C. May 20, 1943, No. 8059. [Class 100 (iv)] A typewriting or like machine is constructed to print trial lines and then to print the same lines justified so as to occupy a complete line, or to print matter for display purposes in which the trial lines may be followed by lines which register with either edge of a column, or are in exact central position. From the final registered copy a printing-plate may be prepared. The machine is fitted with a justifying mechanism which is an improvement on that described in Specification 519,657. The type carriage 12, Fig. 1, is fitted with a platen roller 14, Figs. 1 and 3, and tends to move from right to left as viewed in Fig. 3 under spring action and under control of an escapement device 16 similar to that of Specification 519,657, comprising a wheel 36 geared to a rack 54 on the carriage and to a star-wheel 38, the rotation of which is controlled by dogs 60, 68 on a rocking frame 56 which can be operated by a hollow rod 78 or by a wire 86 which extends through the rod 78. The rod 78 is normally without effect on the frame 56, but when it is raised by the depression of one of three tabular keys 266, and 264, 268, Fig. 2 (not shown), the dogs are depressed and the carriage returns to a position controlled by a tabular stop. Depression of the wire 86 is effected by a lever 88 and a spring 92 acting upon a nut on the end of the wire which passes through the bent arm of lever 88, and the lever 88 is controlled by a spacer key 22, or by the type keys 18. The wire 86 raises the frame 56 and then permits it to drop and thus the wheel 38 rotates through one tooth and the carriage is permitted to advance owing to the engagement of an arm 76 with a roller 74 carried by the escapement device. The arm 76 is fixed when the trial line is typed, but is controlled by justifying mechanism when the final line is typed. This mechanism measures the shortage of a line of characters from the desired column width and automatically increases the carriage movements preferably betwen the words only in typing the final line. The arm 76 is connected to an arm 192, Fig. 3, attached to an arm 190, Fig. 13, which is controlled in position by a roller 191 on a crank-arm 174 forming part of an escapement mechanism comprising a pair of gear segments 120, 122 controlled by rocking frames 132, Fig. 4, one of which is engageable by a shift bar 145 to permit only one of the segments to rock at a time under control of dogs 136, 138, the shift bar 145 being operated by a rod from the variable spacer bar 22 which is depressed at the completion of each word of the trial line. If there are six spaces in a line, the segment 120 is rocked from the Full line position in Fig. 13 to the dotted line position. The segments 120, 122 are connected by a link 179 which is pivoted to curved shoes 162, 178 adapted to move on tracks 154, 171 on the inside of segment 120 and outside of segment 122, the shoes being pivoted to links 158, 172 pivoted to the crank-arms 164, 174. The link 158 is acted upon by a spring 170 tending to move it clockwise around its pivot, but it is held. by a spring-controlled detent 181 until the shift bar 145 is operated to throw-in the escapement mechanism of the segment 122. The shoe 162 then moves on the track 154 to a position depending upon the extent of movement of the segment 120, and the arm 164 moves counter-clockwise so as to bring a roller 168 into engagement with an inclined surface 186 movable in response to the movement of the carriage 12. The movement of shoe 162 is transferred to shoe 178 and the link 172 is moved so as to swing the arm 174 clockwise to an extent which is proportional to the movement of the arm 164, and this movement is dependent upon the shortage of the trial line. As the final line is typed, movements are transmitted to the arm 76 so as to increase the spaces between the words in the final line to fill the line completely. The segment 120 is locked by a crank-arm 185, operated by the shift bar 145 when the final line is typed. A tabular key 264 sets the carriage for the correct position to start the final line. To control the carriage movements so as to enable a printed short line to register exactly with the right or left of a column, or to be in central position for a display copy, the carriage is provided with a number of pivoted tabular arms 234, 236, 238, Figs. 1 and 10, which are adapted to be projected by depression of the tabular keys 264, 266, 268, into the path of stops 322, 324, 326 which are adjustable in position on graduated bars and are set in positions determined by the width of column desired. These stops are carried respectively by members 304, 320, 310 adjustable in relation to fixed bars 290, 292, 294, 296, and the stops 324 are carried by a slide 316 fitted with a gear 318, Fig. 8, engaging a fixed rack and a rack 314 connected to the member 310 which is adapted to move twice the distance moved by the member 320, so that the stop 324 is always set equidistantly from the others and this stop acts in connection with the central tubular arm 236, Fig. 10. The arms 234, 236, 238 are in line at the commencement of the typing of a trial line, and as the carriage advances the arm 238 is moved in reverse direction to the carriage by means of a sliding rack 214 which moves with the carriage and engages a wheel 222 geared to a rack on a sliding bar 208 in which the arm 238 is mounted.. The arm 236 is carried by a floating slide 210 having a wheel 206 in gear with a rack on bar 208, so that the arm 236 moves in a reverse direction to the carriage at half speed. The wheel 222 is integral with a wheel 224 which can be held by a pawl 270, Fig. 4, consisting of three independently swingable fingers, during the resetting of the carriage to the position for commencement of the final line. Normally, the pawl 270 is held out of engagement with the wheel 224 by a detent 276. The keys 264, 266, 268 are operated at the end of the typing of the trial line and respectively set the carriage to form the final line so as to be registered exactly with the left column, the central position, or the right column of a display copy. During resetting of the carriage, the pawl 220 acts to prevent movement of the stops, and lever and trip mechanism associated with a lever 338, Fig. 4, having a roller 336 moving on a guide member 330 formed with a straight face 332, and an inclined face 334, serve to return the operating parts to initial operating position for the commencement of the typing of each trial line.