Patent GB-1045451-A (GB)
Title: Improvements relating to the printing of photographic records, particularly transparencies
IPC: G03B27/62
Filed: 1963-04-16
Abstract: 1,045,451. Photographic printing apparatus. PAKO CORPORATION. April 16, 1963 [April 16, 1962], No. 14947/63. Heading G2A. In a photographic printer, the lens carrier and the holder for the light-sensitive material are each separately adjustable along the optical axis, their positions being determined by a number of pre-set pairs of stops. As shown, the printer is mounted generally on the base plate 20, to which are secured upright support columns 22, 24. The film deck 60 is secured to a carriage 62, and the lens deck 124 to a carriage 128, the two decks being connected by a bellows 130. Both carriages are mounted for controlled vertical movement along the support columns in a similar manner, Fig. 9 showing details of the mounting for the upper carriage 62. This has a bar portion 74, at one end of which is a boss 98 carrying a shaft 100. To this is secured a stabilizer bar 102 having at each end a small wheel 104, 106. The bar 102 is spring-biased so that the small wheels are in contact with extension wall portions 38, 44 of support column 24 (Fig. 17, not shown). The motion of carriage 62 is thus stabilized as it moves up and down. At the other end of bar portion 74 is an enlargement 76 with a bore 78, so that it may slide along a post 58. An extension wall of column 22 carries a brake bar 56, against which a resilient brake shoe 116 is urged by a spring 118 mounted on bar 74. Thus if carriage 62 is released for movement by lever handle 110, it cannot fall quickly. Carriage 62 can be held in various positions by a spring latch 86 sliding in a boss 80 secured to carriage 62. The latch rests on a stop in the form of a nut 172 locked in position on a threaded rod 160. The lens deck 124 and carriage 128 is similarly positioned by a corresponding latch 86a resting on a corresponding stop 174 lower down the same rod 160. The positions of the two stops are chosen so that the image of the transparency or negative in the holder 246 is thrown on to the film in deck 60 with the correct focus and magnification. By altering the positions of the lens deck and film deck with respect to holder 246, the size and magnification of the final image can be varied. The printer is intended to provide for ten different sizes of transparencies. To project these on to the same size of film in deck 60, ten different positional settings of both lens and film decks are required. For convenience and speed of operation, these are provided in the form of a unit 132 which has ten threaded rods such as 160, disposed in a circular array between end plates 134 and 146 (Fig. 6, not shown). Each of these rods carries a pair of stops 172, 174, locknutted into the appropriate positions for locating the film and lens decks in the ten different positions required. The whole unit 132 is rotatably mounted in bearings 144, 180, and has at its upper end a central shaft 178. This carries a gear 184 driven by a further gear 186, operated by a coaxial index wheel 192. A wall part 196 of wheel 192 carries a series of index markings corresponding to the different sizes of the transparency (Fig. 19, not shown), and the wheel is turned until a particular index mark is visible through a window 248. In so turning, the unit 132 has also been rotated via gears 186, 184, so that the appropriate threaded rod 160 and its stops 172, 174, pre-set for that particular size of transparency, are adjacent and lens deck 124 and film deck 60. The brake release handle 110 for deck 60 and the corresponding handle for deck 124 are then both released, and the two decks lowered until the respective latches 86, 86a rest on the stops 172, 174, as shown in Fig. 4. The spring-loaded latches 86, 86a have sloping end-faces, as at 96, 96a, so that if a latch is located below its corresponding stop, it simply slides past as it is raised. The said end-faces are also arcuate (Fig. 9) so that they do not obstruct the unit 132 as it is rotated. The films for deck 60 are housed in a magazine 70. If it is desired to have different sized films in the deck 60 for the final image, separate interchangeable units 132 must be provided, one for each film size. Below lens deck 124 may be mounted a rotatable neutral density multiple filter holder 206 (Fig. 12, not shown), and below that a multiple colour correction filter (Fig. 13, not shown).