Patent GB-904723-A (GB)
Title: Improvements relating to film magazines for typographical photocomposing machines
IPC: B41B21/32
Filed: 1960-04-07
Abstract: 904,723. Film magazines for typographical photocomposing machines. MERGENTHALER LINOTYPE CO. April 7, 1960 [May 13, 1959], No. 12332/60. Class 98 (1). A film magazine for a typographical photocomposing machine in which a film is advanced endwise through the machine in step-by-step fashion and upon which transverse lines of typographical characters are sequentially photographed in spaced relation includes the combination of means operable after the composition of each successive line for effecting such advance of the film to the successive photographic positions, and means separately operable from the advancing means for repositioning the film endwise in order to effect lower line alignment of the typographical characters. The term " lower line " is used to refer to an imaginary line drawn midway between the descenders of one line and the ascenders of the following line and defines the lower white space associated with a line of type. The particular embodiment of film magazine disclosed is suitable for use with a photocomposing machine such as is disclosed in Specification 801,481 and which is controlled by a coded control tape. As shown (Fig. 1), film 20 from a removable supply casette 17 passes into a magazine housing 16, between two rollers 26, 40, over a pivotally mounted platen 30 connected by way of a tube 69-part 69a of which is flexible-to a vacuum bellows 68 (see Specification 825,801), between two rollers 31, 41, roller 31 of which is provided with a sprocket wheel 32 at one end for engaging in feed holes 28 provided at one side only of the film 20 and which roller is connected to the means for advancing the film step-by-step past an exposure aperture 29a, between a cutting device comprising two blades 35, 36, blade 36 of which is operable by lever 58, and finally into a removable take-up cassette 18 wherein the film coils upon itself. Both the cassettes 17 and 18 are provided with means for closing the slits 22, 39 respectively whenever the cassettes are removed from the magazine, said means comprising pivotally mounted rollers 42, spring urged into aperture closing positions and having levers on the shafts 46 co-operating with abutments on the magazine housing for holding said rollers in aperture opening position. Roller 26 is provided with means for maintaining the film taught in the exposure aperture, said means comprising a sprocket wheel 27 at one end of said roller for engaging the feed-holes 28 in the film 20 and a three-armed lever 102 (Fig. 12) in frictional engagement with two clutch plates on the shaft of said roller and under loading by a spring 107, an abutment 110 being also provided for co-operation with arms 108 and 109 to limit rotation of said lever 102. An arm 111 of the lever 102 is normally held out of engagement with a switch 115 by the tension of the film, but at the end of the film is released and operates said switch to give an end-of-film signal. A knob 50 for manually advancing the film is coupled by way of a shaft 51, and gearwheels 52, 55, 56 (Fig. 7) to the shaft 57 of the roller 31. To facilitate loading of the film, the portion of the magazine housing which carries the cassettes, the rollers 23 and 31, and the plate 30 is pivotally mounted as shown in Fig. 3 about the axis of a shaft 116 which forms part of the film advancing means. Punches 96 are provided as described in Specification 825,801 for punching holes in the film at the ends of each line of composed characters. Different film widths may be catered for in that spring-urged locating detents 90a-90c are provided on the core of cassettes 17, and the platen 30 and associated support structure may be replaced by a similar arrangement having the punches 96 spaced at the required distance apart. Alternatively, if it is not required to punch holes in film at both ends of the lines of composed characters, the platen 30 may be retained, and a valve 91 (not shown) provided for applying the vacuum to a variable width of said platen. A shield 97 slidable in a frame 98 is provided for covering the aperture 29a and is operable by means of solenoid 99. Step-by-step film advance.-After composition of a line of characters has been completed, acting in response to signals from the control tape, the film is perforated at both ends of the line by punches 96, solenoid 81 (Fig. 5) controlling the platen 30 by way of connecting rods 86, 86a and 76 and a yoke number 77 is deenergized allowing the platen to move under spring loading to free the film and a solenoid 88 controlling the vacuum bellows 68 is deenergized, also to free the film. A motor 130 and a clutch 135 are energized whereby power is transmitted by way of gears 136, 142, 140 and 146 to drive a cylindrical rack 118 to the top of shaft 116. When rack 118 abuts a stop 119, a torque sensitive clutch 145 operates to de-energize the clutch 135 and to energize a clutch 137 whereby power is transmitted by way of gears 138, 141 and 146 to return the rack 118 to the bottom of shaft 116. When the rack strikes a film advance control nut 120 the torque sensitive clutch de-energizes the clutch 137 and the motor 130. Downward movement of the rack is transmitted to film-feed roller 31 by way of a sector gear 121 and gears 125, 55 and 56, a one-way clutch 126 being interposed to render the upward movement of the rack ineffective as regards film feed. Change of film advance.-After a film advance and before composition of a new line commences, if change of film advance is called for on the control tape, a solenoid 165 is energized to disengage a latch 160 from a latch plate 159, and a film advance control motor 148 is energized so as to adjust the axial position of stop nut 120 on a screw-threaded portion of the shaft 116, power for effecting this adjustment being transmitted by way of gearing 149 and a splined shaft 150, and control of the adjustment being effected by way of a commutator 156 sensitively coupled to the splined shaft 150 by way of worm gearing 151. An accurate end point to the adjustments is obtained by the engagement between latch 160 and latch plate 159, the solenoid 165 being de-energized early for this purpose. In order that the film already advanced may be repositioned to accord with the new amount of film advance, latch 160 is arranged to co-operate with a switch 166, operation of which, as well as de-energizing the solenoids 81 and 88 for freeing the film, energizes the motor 130 and clutch 137, renders torque sensitive clutch 145 inoperative, and energizes a solenoid 128 for rendering by way of link 129 the clutch 126 effective in both directions whereby the film adjusting rack 118 is maintained in contact with the nut 120 in all of its adjustments, either upward or downward. Manual change of film advance.-One revolution of the splined shaft-the minimum automatic adjustment possible owing to the latching arrangement 159, 160-corresponds to an alteration of film leading of 1 point. For adjustments to  point, a manual adjustment means is provided comprising a knob 173 connected to a toothed stop nut 119 rigidly mounted on shaft 116 by way of a shaft 167 and a splined shaft 168. Before adjustment may take place the knob 173 must be depressed against spring loading to disengage a latch arrangement 171, 170, such depression actuating a switch 176 which has the same effect as the switch 166. Rotation of nut 119 which produces a change in spacing between this nut and the stationary nut 120 therefore results in a change in film advance. Coupled to the shaft 167 by way of gears 169, 178 is a second shaft 177 carrying a scale disc 185 for indicating the magnitude and direction of manual adjustments, and two cams 179, 180 for co-operation with two switches 181, 182, the first being actuated whenever any negative leading is set by the manual control and the second operating an indicator whenever any leading, positive or negative, is so set. If switch 181 is closed and zero film advance is called for on the tape, the film advance means will be shut down to avoid damage to the parts. Rotation of the shaft 177 is limited to 360 degrees by the co-operation between a pin 187 on gear 178 and an abutment on the housing 117. Lower line alignment.-If a change of point size during composition of a line of characters is called for by the control tape, and this change of size is obtained as in Specification 823,005 simply by point size changing lenses, then repositioning of the film to effect alignment of the lower lines such as 190, 192 (Fig. 14) is necessary. For this a solenoid 212 is energized to uncouple a latch 210 from a notched flange 209. The latch 210 operates a switch 216 to perform the same function as switch 166, and upon energization of the point size motor 202, the shaft 116 is adjusted axially in its mountings as a result of the engagement of a wheel 201 eccentrically mounted on a collar 200 in a slot 197a of a block 197 fastened to the lower end of the shaft 116, power being transmitted from motor 202 to collar 200 by way of a chain 205 and a commutator 208 being provided on the shaft 199 for control of the direction and magnitude of the adjustment. Alignment of the " X " lines such as 189 and 195 in Fig. 14 is obtained by operation of motor 148 with consequential repositioning of the nut 120, as is fully described above. The magazine may be converted from one point scale to another simply by replacing and repositioning the parts 121, 118 and 129. Specification 752,210 also is referred to.