CA1075949A - Photographic film handling apparatus with circular film pressure plate - Google Patents

Abstract

Abstract of the Disclosure A photographic film handling apparatus of the invention wherein photographic film is positioned at a structure defining an image aperture comprises a circular film pressure plate, which may have a cluster of air holes for an escape of air from a space between the film pressure plate and adjacent photographic film. The apparatus includes means for mounting the film pressure plate adjacent the aperture defining structure this mounting means mounting the circular pressure plate for rotation about an axis perpendicular to the circular surface of the plate. The apparatus further including equipment coupled to the film pressure plate for actuating the film pressure plate relative to the aperture defining structure. A camera including such film handling apparatus and for photographing information on microfilm comprises the said structure defining an image aperture, a lens system for projecting an image of the information to be photographed along an optical path through the image aperture, the film pressure plate equipment connected to the image aperture defining structure and to the clamping device for mounting and restraining the image aperture defining structure and the clamping device against lateral movement relative to the optical path, a carriage, equipment for moving the carriage relative to the image aperture defining structure, lens system and clamping device, and equipment on the carriage for advancing microfilm between the image aperture defining structure and the clamping device.

Description

-( 107594~ ( ~eReEL~C~M RA WI T~ F ~ LM MOVI NC C-~RRI ~GE
AND- VENTED rREssuR~ rLATE--1 Backqxound of the Invention

2 1. Field of the Invention

3 The ~ubject invention relates to photograph~c~equipmént

4 and, more specifically, to microfilm cameras and other film handling apparatus.
6 2. Prior-Art Backqround 7 Mod~rn data stox,age and retrieval relies increasingly 8 on microfilm recording of the data. Microfilm recording, 9 including microfiche technigues, drastically reduces re-guired storage space ~or the data and renders the recorded 11 data easily accessable and retrievable.
12 In the field of data processing, progress in the micro-13 film area ha~ been stifled for a long time by a lack of micro-14 film cameras which in terms of accuracy, preclsion and film handling capability would be up to the attainable speed and 16 resolution o~ cathode ray tube systems and other computer 17 or data processor readout equipment.
~8 Developments in this field in recent years have led-19 to enormmously complex and expen~ive camera systems, many o.~ -which fell short of even approaching the potentialities of 21 electronio computers and other data processor~. ;
22 In particular, the provi~ion of equipment for high-speed 23 and high-preci~ion film pos$tioning at the image aperture 24 continues to be a problem, e~pecially at the extre~ely short focal lengths prevalent in the microimaging art.

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~ ( - 1075949 1 ~wo major aspects of the latter problem have become 2 apparent, namely the alternate clamping and release of the 3 film at the image aper~ure, and the lateral movement of 4 the film and subsequent po~itioning of de~ired film portion~ at that aperture.
6 Proposals in the latter area haveproceeded on the basi~
7 of a provision of a carriage on which film transport eyuip-8 ment was located. A pxoblem in the latter area resides in 9 the lack of a carriage;drive that, in terms of speed and accuracy,would be compati~le with data proce~sing systems 11 and that at the same time would keep the camera within 12 ~onomically feasible limits.
13 Another persistent problem concerns the lack of adequate 14 fllm format exchange equipment that would be adapted in terms of attainable speed of exchange to the requirements 16 of data proce~s~ng system~ and that, at the same tima, 17 would be characterized by an economy of parts.
18 While emphasis bas ~o far been placed herein on the 19 regu~rements of microfilm camera~ in data processing systems, it is to be understood that ~arious aspect~ of the subject - 21 ~n~ention also have utility in other microfilm apparatus or22 eYen in areas of tha broad field of film handling equip~ent.

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., . , ^` 1075949 Summary of the Invention It is an object of the invention to provide improved photographic film handling equipment.
In accordance with the present invention there is provided in a photograpnic film handling apparatus wherein ; photographic film is positioned at a structure defining an image aperture, the imp.rovement comprising in combination:
a circular film pressure plate having an even circular surface for engaging the film;
means for mounting said film pressure plate adjacent said aperture defining structure, said mounting means including means for mounting said circular film pressure plate for rotary ; motion about an axis which is perpendicular to said circular surface of said film pressure plate; and means coupled to said film pressure plate for actuating said film pressure plate relative to said aperture defining structure.
Said mounting means may include a circular member of elastic material connected to said film pressure plate and to said mounting plate.
Said actuating means may include a spring having first ~` and second ends for biasing said film pressure plate toward said :. image aperture defining structure, means for retaining said first spring end stationary relative to said film pressure plate, and means coupled to said film pressure plate and to said second spring end for restricting motion of said film pressure plate away from said first spring end.

j -10~75949 1 _rief De~cription of the Drawinqs 2 The invention and its aspect~ and objects will become 3 more readily apparent from the following detailed description of preferred embodiment~ thereof, illustrated by way of , 5 example in the accompanying drawings, in which like reference . 6 numerals designate like or functionally equ~valent parts, . 7 and in which: , 8 FIG. 1 is a plan view of a microfilm camera in accordance , 9 with a preferred embodiment of the subject invention;
:10 FIG. 2 is an elevat,ion taken on the line 2 - 2 in FIG. 1 11 FIG. 3 is a side view taken on the line 3 - 3 of FIG. 2, 12 of a belt drive system employed in the apparatus of FlGS. 1 . ' 13 and 2;
- 14 FIG. 4 i8 an elevation of a film guide unit wh~ch may be.
- 15 , employed in the appharatus of FIGS. 1 and 27 `~-;.~6 FIGS. 5 and 6/are rear ele~ations of optical units that 17 may.be employed ~n the apparatus.of FIGS. 1 and 27 18 FIG~ 7 i~ a ~ide view of a film olam~ing device taken 19 on the line,7 - 7 ln FIG. 17 FIG. 8 i8 a front v~ew of the film olamping device of 21 F~G. 7, taken on tha line 8 - 8 of FIG. 7~ and 22 FIG. 9 i~ a rear view of an element of the film clamping , 23 devlce ta~ on th~ L1n- 9 - 9 o~ FIG. 7.

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I Descri~tion of Preferred_Embodiments 2 The drawings illustrate a camera 10 and as~ociated 3 eguipment for photographing information o~ microfilm.
4 ~ypically, the illustrated camera will be employed for photo-S graphing pictorially di~played information from a cathode 6 ray tube of a computer or data processor ~not shown) onto 7 microfilm 12. It is, however, to be understood tl~at the 8 illustrated equipment may also be employed for other types 9 of microfilm cameras or even for various types of photograph$c film handling equipmentl as may become appaxent to those Il skilled in the art from the subject extensive disclosure~
12 The camera 10 has a light-tight housing 13 comprising a 13 bottom 14 ~ see FIG. 2 ) and four side walls 15, 16, 17 and 14 18 (~ee FIGS~ 1 and 2) joined to or integral with the bottom 14. A light-tight removable cover 19, shown only in FIG. 2, 16 completes the camera housing 13.
17 A pair of upright posts or stanchion~ 21 and 22 arise 18 from the camera bottom 14 and are attached thereto at 23 and 19 i4. The stanchion~ 21 and 22 guide a carriage 26 having longitudinal or sleeve bearings 27 and 28 attached thereto.
21 The stanchion 21 extends through the carriage bearing 27 aAd 22 the stanchion 22 extends through the carriage bearing 28.
23 A film transport 31 i8 located on the carriage 26.
24 ~he film transport 31 is part of a.film advance dr~ve assembly including a film supply reel drive motor 33 and a 26 film takeup reel drive motor 34, both attache~ to the carrlago 27 26 at the unde~side thereof as seen in FIG. 2.

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` 1075949 1 When energized, the motor 33 rotates a ~upply reel drive member 36 and the mo~or 34 rotate~ a takeup reel drive member 3 37. To avoid crowding of the drawings, no ~ilm reel~ or 4 similar devices have been shown in FIGS. 1 and 2 on the members 36 and 37. However, it is to be under~tood that the illustrated 6 equipment may be employed with, or readily adapted to, any 7 . ~uitable conventional film reel or cartridge which may be 8 rea~onably accommodated within the confines of the camera 9 h~using 13. Accordingly, film supply and takeup r~els or cartridges are only shown symbolically by dotted circles at 41 11 and 42 in FIG. 1.
12 The microfilm 12 extend~ from the reel 41 to an idler 13 roller 44 of a first tension arm 45,across a film guide unit-14 46, over a capstan 47, t~ an idler roller 48 of a second tension arm 49, and to the takeup reel 42. .
16 The tension arms 45 and 49 are pivoted at 51 and 52 17 respectively and form loops of varying size between the reel 18 41 and film guide unit 46 and between the capstan 47 and reel 19 42. Tt i8 a main function of the ten~ion arms 45 and ~9 to equalize the ten~ion acro~s the capstan 47 80 that the fiim!
21 may be driven without the need of the conventional nip roller 22 at the capstan. ~o this end, the film 12 i~ wrapped around 23 the capstan 47 ~n a 150 to 200 wrap and tension arms 45 and 49 2i are interconnected by a helical ~pring 54 having a first end 55 attached to a portion 56 of the flrst tenzion arm situated 26 beyond the pivot 51 as seen frQ~ thQ idler roller 44, and 27 ha~ing a second end 58 attached to a portio~ 59 of the ~econd 28 tension arm located on the sa~e slde of the p~ot 52 a~ th2 29 ldler roller 48.
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1~7S949 1 Th$s ~acros~ the pivots~ spring bias has been found to 2 prom~te an excellent tension egualization of the film acros~
3 the capstan 47 ~or ~ rapid and slip-free traction of the 4 f~lm by the capstan. ~hat traction may be further ~ncreasea S ~n a conventional mannex by equipping the capstan 47 with an 6 outer sleeve 61 of rubber or another elastomer.
7 The capstan 47 i8 driven by a capstan motor 62 which i8 8 attached to the carriage 26~ The capstan ~otor 62 may be 9 energized by a control drive 63. That control drive is not particularly illustratecl since it does not form part of 11 the subject invent~on and since capstan drive ~ontrols are 12 well known in the specialized film drive and magnet~c recording 13 dr~ve arts. The chief purpo~e of the film drive is to advan~e 14 the film in a controlled manner in a first direction indicated by the arrow 65.
16 ~he angular position of the tension arms 45 and 49 controls 17 ln a conve~tional manner the energizat~on of the reel drive 18 motor~ 33 and,34. To this end, the tension arms 45 and 49 19 actuate angular position pick-up devices 67 and 68.
2 The pick-up device~ 67 ana 68 may be of a variable 21 re~istor or photoelectric type providing in lines 71 and 22 72 signals corresponding to the angular position of the tensio~
23 arm~ 45 and 49, respectiv~ly. ~he ~ignal indicative of the 24 angular position of the tension arm 45 is applied by the l~ne 71 to a control 74 which accord~ngly varies th~ energ~zat~on 26 oS the reel motor 33.

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, '' ' . ,-- .~ _ . , ' .~: ' 1 Similarly, the signal indicative of the angular 2 posit~on of the tension arm 49 i8 applied by the line 72 3 to ~ control 75 which accordingly varie~ the energ~zation 4 of the reel drive motor 34. Again, the contro~ 74 and 75 S are not particularly illustrated, since their nature and 6 function are well known in the art of ~peclaliz~d ~ilm 7 drives and magnetic recording tape transports. In brief, 8 as the loop of film between the reel 41 and the film guide 9 unit 46 decreases, the pick-up 67 and control 74 will cause the drive 33 to issue m~re film from the reel 41. Conversely, 11 lf the 8 ~ ze of the loop between the capstan 47 and the reel 12 42 increased, the pick up 68 and control 75 w~ll cause the 13 reel drive 34 to increase the takeup of film on the reel 42.`
14 The stanchion~ 21 and 22 and the longitudinal or axial bearings 27 and 28 cooperate in restricting movement of the 16 carriage 26 to ~ovement in parallel second and third direction~
17 being opposed to each other. In FIG. 2, these d~rections are 18 indicated by the arrows 77 and 78 and it will be noted that, 19 in the case of the apparatus shown in FIGS. 1 and 2, the direction 77 i8 an up direction while the direction 78 i8 21 a correspond~ng opposite down direction. The directions 77 22 and 78 both extend at right angles to the direction of film 23 movement 65 imposed by the film drivè of the transport 31 24 on the carriage 26. It will thu~ be noted that the combination of the film dri~e including the transport 31 on the carriage 26 26 and the carriage 26 itself w~th the equipment for driving 27 ~t, more fully descr~bed below, cooperate in plae~ng any desire~ . i 28 portion of the fi~ 12 at the ~mage apertur~ presently to be 29 descr~bed of an optlcal unit 81.
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` ~ - 1075949 The optical unit 81 shown in FIGS. 1 and 5 includes a photographic lens system symbolically shown at 82 and an integral extension 83 defining an image aperturc 84.
The upright wall 16 of the housing 13 has an aperture 85 for receiving the optical unit 81 at the extension 83.
- Part of a releasable bayonet attachment is shown at 86 in FIG. 5, it being understood that a corresponding bayonet socket (not shown) is provided in or at the housing wall 16, whereby to provide a means for releasably mounting the optical unit 81 on the camera 10.
The camera further includes a device for selectively clamping microfilm 12 against the optical unit extension 83 adjacent the image aperture 84. The clamping device 88 is mounted on an upright bracket or stanchion 89 which extends through an aperture 91 in the carriage 26 and which is fastened to the camera base plate or bottom at 92 independently of the carriage 26. In this manner, the stanchion 89, during movement of the carriage 26 and otherwise, mounts the film clamping device 88 against lateral movement relative to an optical path 94 along which an image of the input information is projected by the lens system 82 through the image aperture 84.
The clamping device 88 includes a film pressure plate 96. In accordance with the preferred embodiment illustrated in FIGS. 1, 2, 7, 8 and 9, the film pressure plate is circular, having an even circular surface 96' (see FIG. 7) for engaging the film (see FIG. 1), and is-laterally dished for maximum protection of the film 12 during rapid advancement and clamping.
Prior-art equipment of the subject type was burdened with extreme tolerance problems stemming from a carriage-mounted image aperture and film pressure plate. According to the subject in-vention, these problems are eliminated by the stationary or fixed aperture 84 or 173 and pressure plate 96, thereby relieving the carriage design of extreme tolerance problems.

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1 By way of example, the circular pressure plate 96 may 2 be formed of a light metal, such as aluminum which may be 3 anodized.
4 As best seen in FIG. 8, the film pressurs plate 96 has a cluster of air holes 98, as well as a circular air hole 6 arrangement 99 for an escape of air from space between the 7 film pressure plate 96 and adjacent microfilm 12. In practice, 8 this l~as been found an important feature of the illustrated 9 preferred embodLment of the invention, since it elLminate~
prior-art blurring or defocusing effects attributable to 11 the formation of an air cushion or a shock wave between the 12 pressure plate and the fi~m when the pressure plate rapidly 13 clamped the film against the optical unit extension 83 at 14 the aperture 84.
The clamping device 88 further includes a mounting plate 16 100 having a further clùster of air holes 101 corresponding 17 to the cluster 98 in the film pressure plate. A washer-shaped 18 member 102 of rubber or another elastic or elastomeric material 9 i8 disposed between and connects the film pressure plate 96 to the mounting plate 100. The member 102 i~ preferably circular 21 and may be connected to the film pressure plate ~6 and mounting 22 plate 100 by an adhesive substance. The elaEtic member 102 23 has an aperture 103 communicating w~th the air hole clu~ters 24 98 and 101.

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, 1 In this manner, air can e~cape and enters through the 2 film pressure plate 96, mounting plate 100 and elastic 3 interconnecting member 102. In addition, the elastic member 4 102 cushions or absorb~ shock loads which would otherwise affect the film.
6 The mounting plate 100, in turn, i~ mounted on a reduced 7 diameter portion 105 of a ferromagnetic movable armature 8 or plunger 106. The p~unger 106 extends into a solenoid 107 9 having a stationary arnature 108.
The solenoid 107 and s~ationary armature 108 are connected 11 to the stanchion or mounting bracket 89 by screws or other 12 fasteners 110~ In this manner, the clamping device actuator 13 represented by the solenoid 107 and armature 108 is maintained 14 stationary relative to the wall 16, optical unit extension 83 and image aperture 84, independently of the movement of the 16 carriage 26.
17 The solenoid 107 de~elops a magnetic force which attracks 18 the plunger 106 to the stationary armature 108 upon closure 19 of a normally open switch 113, which connect~ the solenoid to a source of electric power, symbolized by plus and minus 21 signs.
22 In this manner, the film pressure plate 96 is mo~ed away 23 from the aperture 84 for a release of the film 12 between 24 the optical unit extension 83 and film pressurs plate 96.

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1 During the actuation of the switch 113, f~lm 12 may 2 thu~ be advanced by the transport 31 between the film pre~sure 3 plate and the aperture 84.
4 Upon release of the switch 113, the film press~.e plate 96 is rapidly advanced by.a helical spring 115 toward the 6 image aperture 84 and microfilm 12 is then clamped against :. 7 the optical unit exten.sion 83. An image of the input information 8 from a cathode ray tube or other input device (not shown) i8 9 then projected by the lens system 82 through the image aperture 84 onto the photographic film 12. Because of the action of 11 the film pressure plate 96 t an excellent positionil~g of the 12 microcilm 12 at the image aperture 84 is realized.
13 The actuator spring 115 which biases the film pressure -14 plate toward the image aperture defining extension 83 has . 15 a first end 117 retained stationary relative to the film - 16 pressure plate by the 6tationary clamping device armature 7 108.
- 18 The clamping device ~iasing spring 115 has a ~econd end 19 118 which extend~ around the reduced diam~ter portion 105 of the solenoid plunger 106 in a lost-motion connection.
21 On the one hand, this allow~ the film pres~ure plate 96 a 22 certain lost-motion tra~el relative to the spring end 118 23 and the stationary solenoid armature 108. On the other hand, 24 the spring 115, through it~ second end 118,will restrain the 25 film pre~ure plate 96 from further outward motion at the 26 end of the lost-motion traval ~ ~ ' ' ' .

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1~75949 1 In pract~ce, these are important features of the 2 illustrated preferred embodiment, since they prevent mal-3 function of, and damage to, the equipment both when the 4 optical unit 81 is inserted in the camera and wh~n the same is remoYed so that the bias spring 115 would tend to urge 6 the film pressure plate outwardly as seen from the ~tationary 7 armature 107. As another important feature of the illustrated 8 preferred embodiment, the solenoid plunger 106 i8 free of 9 lateral restraint whereby the film pressure plate 96 i5 mounted for rotary motion about an axis 121 which is perpendi-11 cular to a circular surface of the film pressure plate, as 12 best seen in FIG. 7. This ability to carry out a rotary 13 motion prevents the film pressure plate from becoming 6tuck 14 in any angular position and from exerting an uneven load on the microfilm 12.
lb Where necessary, the optical unit 81 may include a camera 17 - shutter ~not shown), which may be of a conventional type~
18 A shutter may, however, be dispen~ed with lf an ele--tronic i9 shutter action results from an appropriate and convent~onal .
energization of the cathode ray tube `or other display device 21 ~not shown) from which the lens sy~tem 82 pro~ect~ the input 22 ~mage of the camera 10.
23 The switch 113 may be replaced by an electronic switching 24 deYice or circuit for rapid actuation-of ~he film pressure plat~
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1 Such an electronic switching device or circuit 2 would not be part of the subject invention and is thus not 3 illustrated in the drawings.
4 The drive of the carriage 26 which drives this carriage with bearings 27 and 28 selectively up and down the 6 stanchions 21 and 22 in t~ie direction of the arrows 77 and 78 7 includes an endless timing belt 131 having a plurality of 8 teeth 132 located at the i.nside thereof in an endless arrange-9 ment as seen in FIG. 3. l'iming belts as such are well known .-in the art of servo mechanisms.
11 As shown in FIGS. 2 and 3, a pair of toothed pinions 133 12 and 134 are rotatably mounted in spaced relationship by a 13 frame 135 and cooperate in mounting the timing belt 131 in an 14 endless loop having a straight portion 136 extending parallel to the above ment`ioned opposed directions of carriage movement 16 77 and 78. The frame 135 is attached to the base or bottom 17 plate 14 of the camera housing at 138.
18 A bracket 141 is attached to tXe carriage 142 and serve3 li as a means for transmitt`ing motive power from the timing belt., 131 to the carriage 26. To this end, the brae~et 141 has a 21 straight portion 143 extending parallel to the opposed directions 22 of carriage movement 77 and 78 and to the straight portion 136 23 of the timing belt 131. The ~ree end of the power transmitting 24 bracket 141 is attached to the timing belt 131 at the straight belt portion 136 by fastening devices 145 and 146.

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1 An electric motor 148 drive~ the tLming belt 131 in 2 a first sense for movement of the carriage 26 in the direction 3 77 and alternatively in an opposite second 3ense for movement 4 of the carriage in the direction 78. To this end, the motor 148 rotates a pinion 149 which, in turn, drives a gear wheel 6 151 via an endless time ~elt 162. The gear wheel 151 i8 : 7 attached to or integral with the pinion 133.
8 The carriage drive motor 148 may be energized and controlled 9 in any desired manner. For instance, the motol 148 may be ener-gized by a control 154 which varies the energization of the 11 motor 148 in response to a first signal provided by a tacho-12 meter 155 driven by the motor 148 and a second signal ~upplied .13 via a line 156 by a carriage position sensing device 157. The.
14 tachometer 115, as well as the position sensing device 157, 15 . may be of a conventional type. For instance, the position 16 sensing device 157 may include a photocell pick-up tnot shown) 17 which senses the position of the carriage 26 by ~neans of an 18 analog gray scale or digital line raster device 159 attached 19 to the power transmitting bracket 141.
The carriage drive according to the subject invention . 21 and its preferxed embodLments has been found very accurate `~ 22 and reliable in positioning the carriage 26 rapidly and with ; 23 great precisio~. In the illustrated preferred embodLment, both 24 elongate sides 136 and 162 of the timing belt 136 are parallel to the opposed directions 77 and 78 for a tighter control of 26 the carriage positioning process without any objectionable play.
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107S9~g 1 Also, all portions o~ the endless timing belt 131 are 2 at all tLmes located to one side of the carriage 26 for 3 all positions of the carriage. This di~tinguishes itself 4 favorably from prior-art carriage drives wherein a drive belt or cable extended on both sides of the carriage, thereby 6 giving rise to objectionable play or lo~t motion.
7 The illustrated camera 10 is also charac~erized by a 8 rapid and convenient adaptability to various film formats.
9 of primar~ interest in this rèspect are the 16mm microfilm format and the 105mm microfiche format. To serve these two 11 formats, the illustratecl camera not only includes the above 12 mentioned ~ptical unit 81 shown in FIGSo 1 and 5, but also 13 a similar optical unit 171 shown in FIG. 6.
14 The optical unit 171 is exchangeable on the camera with the optical unit 81 and, for that purpose, also includeR the 16 bayonet socket locXing devices 86. The optical unit 171 17 also has an integral extension 83 for defining an image aperture.
18 The ima-Ja aperture 173 defined by the latter extension has a 19 different format than the image aperture 84 of the optical ., unit 81~ corresponding to diferences in image size and format 21 between the two optical units 81 and 171.
22 The film clamping device 88 with film pressure plate 96 23 is common to the optical unit 81 and 171 as either is releasably 24 mounted on the camera wall 16. Because of the stationary : mounting of the armature 108 of the film clamping device 88 by 26 the mounting bracket or stanchion 89, one and the same film 27 pressure plate and clamping device may be used for all ormat~
28 handled by the micro~ilm camera 10.

, 1~75949 1 Thi6 dispenses with the prior-art nece~sity of having 2 to exchange film pressure plates for different film f~rmats.
3 Also, it will be noted that the illustrated stationary mounting 4 of ~le clamping device and the circular configuration of the S film pressure plate 95 keeps the mass of the film pressure 6 plate at a minimum for rapid and accurate actuation at a ; 7 minimum of motive power.
8 The illustrated microfilm camera alss include~ facilities 9 for alternatively guiding a film having a first format (e.g.
105mm) and a film having a second format (e.g. 16mm~ in between 11 the film pressure plate 96 and the aperture defining structure 12 83 of either of the optical units 81 and 171. In this respect, 13 it is to be understood that neither of the optical units 81 14 and 171 is necessarily restricted to a specific film format.
Rather, the optical units 81 and 171 may be designed in a 16 conventional manner so as to be usable with either film format.
17 For instance, one of the units 81 and 171 may have a 24X
18 lens system and the other of these units may have a 42X lens 19 system.
~he film format exchange facilities of the illustrated 21 prefer~ed camera embodiment include a film guide base 181 22 located on the carriage 26 in the vicinity of the film pressure 23 plate 96, and two exchangeable film guide units 182 shown in 24 FIGS. 1 and 2 and 183 shown in FIG. 4 for guiding, respectively, film having the mentioned f~rst format (e.g. 105mml and film 26 having the men~ioned second format (16mm).
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1075'~49 1 The film guide u~it 182 includes cylindrical film guide 2 members 185 mounted in a frame 186 comprising cylindrical 3 posts 187 which may be insertable into corresponding holes 4 (not shown) of the film guide base 181.
T~ie film guide unit 182 includes two manually actuable 6 elongate screws 189 which releasably anchor the unit 182 to 7 the film guide base 181. The configuration of the cylindrical 8 film guide members 185 is adapted to the first film format.
9 The film guide unit 183 shown in FIG. 4 is closely sL~ilar to the the film guide unit 182 so that like reference numerals 11 are employed to designate like or functionally equivalent parts.
12 Instead of U-e cylindrical film guide members 185 of the unit 13 182, the unit 183 has cylindrical film guide mel,~ers 191, 14 the c~nfiguxation of which is adapted to the second or 16mm film format shown in dotted lines at 192. As also shown in 16 dotted outline in FIG. 4 at 193 and 194, respectively, the 17 second format or 16mm film may be dispensed from a cartridge 18 customary with that format and the reel drive member 36 may 19 be equipped with an adaptor 194 for accommoda~ting that cartridg~. The tension arm r~llers 44 and ~ have cylindrical 21 cutouts 196 and 197 for accommodating the smaller film format.
22 The obvious ease with which the film guide units 182 23 and 183 are mutually exchanged greatiy augment~ the format ii adaptability of the illustrated camera.in terms of speed and operating convenience.

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Claims (4)

1. In a photographic film handling apparatus wherein photographic film is positioned at a structure defining an image aperture, the improvement comprising in combination:
a circular film pressure plate having an even circular surface for engaging the film;
means for mounting said film pressure plate adjacent said aperture defining structure , said mounting means including means for mounting said circular film pressure plate for rotary motion about an axis which is perpendicular to said circular surface of said film pressure plate; and means coupled to said film pressure plate for actuating said film pressure plate relative to said aperture defining structure.

2. A film handling apparatus as claimed in claim 1, wherein:
said mounting means include a circular mounting plate, and a circular member of elastic material connected to said film pressure plate and to said mounting plate.

3. A film handling apparatus as claimed in claim 1 or 2, wherein:
said actuating means include a spring having first and second ends for biasing said film pressure plate toward said image aperture defining structure, means for retaining said first spring end stationary relative to said film pressure plate, and means coupled to said film pressure plate and to said second spring end for restricting motion of said film pressure plate away from said first spring end.

4. A film handling apparatus as claimed in claim 1 or 2 wherein:
said actuating means include a spring having first and second ends for biasing said film pressure plate toward said image aperture defining structure, means for retaining said first spring end stationary relative to said film pressure plate, and means coupled to said film pressure plate and to said second spring end for restricting motion of said film pressure plate away from said first spring end, and wherein:
said motion restricting means include means for providing a lost-motion connection between said film pressure plate and said second spring end.