Abstract:
The camera head of a planetary camera system is movably mounted on a frame of the system. Film members (e.g. aperture cards) are exposed in the camera head. A stationary film-processing station is mounted on the frame in a position remote from the camera head and is linked to the camera head by a light-tight extensible film member conveying means. Telescopic tubes containing endless conveyor belts of variable effective length are preferred for the conveying means.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to an improved planetary camera system. 
     It is known to expose aperture cards in a movable camera head and then subsequently to process the exposed cards directly in the camera head. 
     SUMMARY OF THE INVENTION 
     This invention, in one aspect, relates to an improved planetary camera system in which light-tight transporting means is provided to convey exposed aperture cards from a movable camera head of the system to a stationary film-processing station of the system. 
     Conveniently the light-tight transporting means comprises an extensible/contractable (e.g. telescopic) tubular member which links the camera head to a fixed region of a support frame of the head. The tubular member conveniently houses at least one endless card-conveying belt for transporting the exposed card through the tubular member. Preferably there are two pairs of opposed belts (one pair engaging the card on opposite sides adjacent to one longitudinal edge and the other pair adjacent to the opposite edge) and each belt comprises a double loop so that the overall length of the conveying run of each belt can change without there being any need for the overall length of each belt to change. 
     The end of the transporting means adjacent to the camera head can be adapted to receive an exposed card from the outlet end of an automatic card feed system within the camera head that takes cards one at a time, on demand from a camera operator, holds them in an exposure station (behind the camera lens) for correct exposure, and feeds them away from the exposure station at the conclusion of the exposure. 
     The end of the transporting means adjacent to the processing station would normally cater for downward movement of the cards and free fall can be permitted between an output end of a transverse conveying means removing exposed cards from the camera head and an input end of a conveying means passing through the processing station. 
     If required a 90° or 180° turn of cards can be effected during the downward movement, and where free fall is employed this is conveniently effected in one or two 90° stages. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     One embodiment of camera system in accordance with the invention will now be described, by way of example, with reference to the accompaying drawings, in which: 
     FIG. 1 shows a general view of the complete system, 
     FIG. 2 shows schematically how the camera head is linked to the frame of the system by a telescopic tubular member, 
     FIGS. 3 to 5 show schematically how cards move in different stages of the transporting means. 
     FIG. 6 is a partially sectioned plan view of part of the central region of the telescopic member sectioned on the transporting plane of the aperture cards therethrough (i.e. on the line VI--VI in FIG. 7), 
     FIG. 7 is a sectional side elevation of the central region shown in FIG. 6 when the member is near its maximum length, 
     FIG. 8 is a cross-sectional view on the line VIII--VIII of FIG. 7, 
     FIG. 9 is a partial section showing the inlet to the telescopic section, and 
     FIG. 10 is a partial section showing the outlet of the telescopic section. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The camera system shown in FIG. 1 comprises an A-frame 1 supporting a copy board 2 and movable above the copy board 2 on a beam 3, a camera head 4. As is known, the drawing to be copied is placed face upwards on the board 2, illuminated (with lights not shown) and the beam 3 and camera head 4 are moved vertically up or down above the board 2 to get the required reduction ratio for the drawing in question. An aperture card from a magazine in the camera head 4 (shown in FIG. 3) is then exposed in the head 4, and the exposed card has to be developed before it can be exposed to light again. 
     In prior art arrangements the film-processing station has been included in the head 4 but this now appears not to be the best location for it. 
     In the system shown in FIG. 1, the film-processing station (5) is located below the board 2 and the exposed cards are automatically (and under light-free conditions) led from the head 4 to the station 5 by a transfer means 6a, 6b. 
     The transfer means 6a is movable with the head 4, and is provided by a telescopic pair of tubes 7a, 7b (see FIG. 4) containing endless belt drives, tube 7a being pivoted to the head 4 and tube 7b to the frame 1. The transfer means 6b allows near-vertical free fall which includes two 90° turns of the cards (to ensure the emulsion side of the film is the correct way up for processing in the station 5). 
     To minimise the percentage change in length of the transfer means 6a from the lowest position of the head 4 (shown at 4A in FIG. 2) to the highest position of the head 4 (shown at 4B in FIG. 2), the tube 7b is pivoted to the frame 1 roughly mid-way between these lowest and highest positions. 
     FIG. 3 shows how unexposed aperture cards (emulsion side down) move one-by-one from a reservoir 10 to the exposure station behind the lens 11. A pair of rollers 12 engage the card to remove it from the bottom of the reservoir and forward it to a second pair of driven rollers 13. Light idler rollers 14 rest on the conveyed card adjacent its edges, the rollers 13, 14 together giving a light sideways urge to the cards to ensure they engage a side register surface. A solenoid-energised stop means 15, holds a card in the exposure station during exposure and then releases it to be carried forward by twin roller pairs 16, 17 and 18, 19. On leaving the roller pairs 18, 19 the edges of the card are trapped between pairs of endless belts 20, 21 and led to the outlet 22 of the camera head 4. 
     FIG. 4 shows the telescoping tubes 7a, 7b and two of the four endless belts 30, 31 included therein. Each belt forms a double loop around four rollers, two 32a, 32b, mounted on tube 7a and two 33a, 33b mounted on the tube 7b. Thus as the tubes 7a, 7b telescope, to accommodate for vertical movements of the head 4, the conveying run of each belt 30, 31 varies without significantly altering the tension in each belt. The outlet of the tube 7b is shown at 34 and the pivot axes of the tubes 7a, 7b to the head 4 and frame 1, respectively are shown at 35 and 36. The joints between the tubes 7a, 7b and between tube 7a and the head 4 and tube 7b and the frame 1 are protected from light ingress by felt pads or the like. 
     The card drops from the outlet 34 into a light-tight tube 40 shown in FIG. 5, where it meets two spaced-apart edges 41, 42 inclined to one another in parallel spaced-apart planes. As the leading end of the falling card meets the edges 41, 42, the card turns through 90° about a generally vertical axis to pass between them. 
     A second pair of inclined spaced-apart edges 43, 44 cause the card to make an additional 90° turn so that as it reaches the outlet 45 of the tube 40 it is ready to be bent through 90° and pass horizontally into the station 5, emulsion side down for chemical processing by sprays from below. 
     By coupling the drives for the various rollers and belts used for card transport, accurate synchronisation of movement is possible to provide for fully automatic operation. 
     FIG. 1 also shows a control panel 50 which can be used to control the system and also to print a suitable code designation on each card processed in the station 5. 
     From FIGS. 6, 7 and 8 it can be seen that each tube 7a, 7b of the telescopic transfer means 6a is formed from a generally rectangular channel section 57a, 57b, closed by a removable lid 67a, 67b. The lid 67a does not extend the full length of the tube 7a, since the lid serves to provide a light-tight cover to the tube and is not required on that part of the tube 7a which is never withdrawn from the tube 7b. The light sealing pads between the tubes 7a and 7b are shown at 58, 59 in FIGS. 6 and 7. 
     The eight rollers 32a, 32b, 33a and 33b are all of a similar design and each exhibits an outer pair of edge grooves 50 and an inner pair of edge grooves 51. The lower belts 30 run in the grooves 50 of the four lower rollers and the upper belts 31 run in the grooves 51. This arrangement ensures that the aperture card is nipped between the two belts 30, 31 adjacent to each long edge of the card, in its transportation through the tubes 7a, 7b. The film covered window of each card will occupy the position X between the two chain lines in FIG. 8 and will thus not be contacted by anything during its transportation from the exposure station to the film processing station 5. 
     From FIG. 7 it can be seen that the rollers 33a pass through elongate slots 53, 54 in the channel section 57a and this permits the necessary telescoping movement between the tubes 7a and 7b. The position of the rollers as shown in FIG. 7 represents the maximum length of the transfer means 6a (i.e. when the camera head 4 is at its lowest or highest position) and the chain line positions 33a&#39; in FIG. 7 represent the position of the rollers in the slots 53, 54 when the camera head 4 is in the mid position. 
     FIG. 9 shows the inlet end of the transfer means 6a with the camera head 4 in its lowest position and the chain line 60 in FIG. 9 shows the relative position of the tube 7a when the camera head 4 is in its highest position. It will be noted that the plane of an aperture card nipped between the belts 30 and 31 adjacent to the rollers 32a (i.e. at the inlet end of the transfer means 6a) passes through the pivoting axis 35 of the tube 7a, so that smooth feed of cards from the outlet 22 of the camera head transportation system (not shown in FIG. 9) to the belts 30, 31, will always occur. 
     One or more light-masking sheets 61 are provided adjacent the joint between the tube 7a and the camera head 4 to prevent light ingress when there is relative movement therebetween. 
     FIG. 10 shows, in greater detail, the outlet end of the transfer means 6a and the way in which the belts 30, 31 are driven. 
     A motor (not shown) drives a main pulley 70 and a drive belt 71 and the latter engages pulleys 72 and 73. Toothed wheels 74 transmit the drive from the pulley 72 to a four-grooved belt roller 75 and a pair of endless belts 76 (only one shown) link the roller 75 with the upper roller 33b at the outlet end of the transfer means 6a. Since the belt 31 uses the grooves 51 in the roller 33b the belts 76 can use the grooves 50. This arrangement ensures that the pulley 70 drives the belt 31. 
     The pulley 73 is fast with a further four-grooved belt roller 77 which, via a pair of endless belts 78 drives the lower roller 33b and thus the belt 30. The belts 78 locate in the grooves 51 in the lower roller 33b. 
     When aperture cards reach the end of their transportation between the two pairs of belts 30, 31, they move into a space defined by the two pairs of belts 76, 78 and three further pairs of belts 79, 80 and 81. If the camera head 4 is in its lowest position, the aperture cards will enter this space in the direction of the arrow L. If the camera head 4 is in the middle or uppermost positions the entry directions will, respectively, be represented by the arrows M or U. In each case the leading end of the card will contact one of the pair of belts 79 or 80 and will thus be fed down between the four belts 80, 81 to pass, in the direction of the arrow F further into the transfer means 6b. 
     The belts 79 are carried by the belt roller 75 and a four-grooved belt roller 82 and the belts 80 and 81 pass around four-grooved belt rollers 83 and 84, respectively. 
     To ensure a light-tight connection between the transfer means 6a and 6b, light masking sheets 62 are used. 
     Although two 90° turns are imparted to each card during its transit of the means 6b in the illustrated arrangement by realigning the card transport path within the station 5 it is possible to operate with just one 90° turn. 
     Other modifications of the illustrated embodiment are clearly possible within the scope of the following claims.