US3854809A

US3854809A - Photographic apparatus

Info

Publication number: US3854809A
Application number: US00375339A
Authority: US
Inventors: J Driscoll
Original assignee: Polaroid Corp
Current assignee: Polaroid Corp
Priority date: 1972-10-24
Filing date: 1973-07-02
Publication date: 1974-12-17
Anticipated expiration: 1991-12-17
Also published as: CA1019610A; DE2351396C2; IT994302B; GB1440585A; JPS4981028A; AT335282B; NL180458C; JPS5719404B2; ATA871873A; CH571231A5; NL7314549A; FR2326844A5; AU6130073A; DE2351396A1

Abstract

Photographic apparatus including film-advancing structure for asymmetrically engaging a film unit and moving it into engagement with a pair of pressure-applying members. The pressure-applying members are adapted to rupture a container of processing composition located near one end of the film unit and spread the contents thereof across a photosensitive layer of the film unit to initiate formation of a visible image. The asymmetrical engagement of the film unit by the film-advancing structure may result in the film unit being slightly canted as it moves into engagement with the pressure-applying members. Advancing the canted film unit between the pressure-applying members may result in an incomplete spread of the processing composition, i.e., some portion of the photosensitive layer will not be covered by the processing composition. This condition is substantially obviated by providing the pressure-applying members with the facility to spread the processing composition across the photosensitive layer in a layer having an asymmetrical thickness, as measured in a direction transverse to the direction of movement of the film unit through the pressure-applying members.

Description

United statesgPatent 1 1 11-11 3,854,809

DllSCOll 51' Dec. 17', 1974 PHOTOGRAPHIC APPARATUS -[57] ABSTRACT [75] Inventor: John J. Dris coll, Andover, Mass. 7 I

Photographic apparatus including film-advancing U 1 Asslgne? 322: ""F" Cambndge structure for asymmetrically engaging'a film unit and y moving it into engagement with a pairof pressure- Filed: July 2, 1973 applying members. The pressure-applying members 'are adapted to rupture a container of processing com- 1 position located near one end of the film unit and 1 Related U.S. Application Data spread the contents thereof across a photosensitive [63] continuationqmpan f 229,669, t 24, layer of the film unit to initiate'formation of a visible v 1972, abandoned, image, The asymmetrical engagement of the film unit 1 I by'the film-advancing structure may result in the film [521 U.S. c1. 354/86 unit being s g y canted as it moves into, engagement 51 1111.0. .G03b 17 50 with the P pp y members Advancing the [58] Field of Search, 95/89 R, 89 L, 89 A, 13; canted film unit betweenthe p pp y 354/83 85 86 302 betsmay result in an incomplete spread of the pro- 2 1 i cessing composition, ile some portion of the photo- [56] R f e Cit d sensitive layer will not be covered by the processing UNITED T E P T gompositzilon. "{jhis condition 'ils'substantiglly obvriiatid jj I I ,y provi ing t e pressure-app ying-mem ers-wit t e l3/1963 Ha r n1lton.......: 95/13 facility spreadnthe processing p io across [1967. Murphy 95 13 3,4 6,427 12/1968 Murphy 95/13 x F phoFosensmle layer "1 1 m 3,537,371 11/1970' Finelli 95/13 thlckness, as measured a drectwn transverse 3,625,130 12/1971 Van Allen et al.... 95/89 L x 0 the direction of movement of fi m unit thr ugh 3,673,938 7/1972 Michatek 5 111.... 95/13 th p ssu -apply g rs- 3,739,701 6/1973 12 11611612111.1411 95/13 3,742,834 7/1973 Thoenen 95/ l 3 Primary Examiner -Fred L. Braun Attorney, Agent, o r Firm Ailired E. Corrigan 1 35 Clain1s,'7 Drawi ng Figures V VPATENIEUEECII new sum 1 er 3 image within-the I ing the film unit toa-viewing'station'. i

r PnoTooRAPuIC- APPARATUS- :Ross REFERENCE TO RELATE APPLICATION This application is in part a continuation of my copendingtapplication Ser. No. -299,669,"filedOct. 24,

1972 now abandoned.

BAcxoRouND oF THE NvENTloN 1. Field of the Invention This invention relates to photographic apparatus of the type adapt-edfto spread'a processing'composition across an exposed photosensitive layer; 3

' 2. Description of thePrior Art Photographic apparatus of the self-developing type are well known-in the art and generally include film advancing means for engaging and moving an exposed film unit out of its exposureposition and into engage ment with a pair of pressure-applying members, e.g.,

skewed a few degrees as it enters the bite" of the pres sure-applying means, the processingvcompositioncontained within the'pod would notonly spread from the front of the film .unit to the rear but it,the composition, would also have a tendency to move laterally toward one side of the'film unit because of the angle "between-the pressure-applyingmeans and the discharge end(s) of the pod(s). Movement of the processing composition toward .the' one side. of the film unit and away from the other side thereof during front to rear spreading mayresult in a spread which does not cover the rear corner of the other side of the film unit. This problem .is substantially obviated byspreading the process composition on the other side of the film un'it in.a thinner layer than on the one side thereby spreading the available processing composition on the other'sidelover a greater area before-it becomes depleted; This is accomplished, in a preferred embodiment, by providing the rollers. The film unit includes, a pod o'rcontainer, of

processing composition, e.g.,- liquid, havinga sealed,

rearwardly facing discharge end which is parallel with and adjacent to a leadingend of the film unit. The rollers are adapted to engage the .leading end of the film unit and the pod to generate suffi'cient pressure within the processing composition to rupture thefseal and spread the contentsthereof across a photosensitive layer of the film unittoinitiate formation of a visible film unit while simultaneously advanc- Generally, the film-advancing" means is constructed and positioned such that the film unit is not canted 'a's it moves into engagement with the bite of thejrollers, i.e.,-the,leading end of the filmunit is generally parallel with the axes of the rollers therebyenablingthe rollers to maximize the spread of the processing composition across thephotosensitive layer of the film unit. Obvi-' ously, this criterion 'severelyrestricts' the jdesi'gners choice and arrangement of the film-advancingmeans.

Therefore, there is a needvtfor a camera of the selfdeveloping typ'e'wherein the film unitmaybe advanced in a canted orientation between-the pressure-applyingmembers without adversely affecting the quality of the spread ofprocessing composition across the photosensitive. layer;

SUMMARY OF THE INVENTION out of its'exposure position and into engagement with the pressure-applyingmeans. Ordinarily, orienting the film unit in a skewed manner prior to its'entry between the pressure-applying means willincrease the possibility that the contents of the pod of processing composition located adjacent the leading end of the exposed film unit will not, be spread over the entire areaof the film units photosensitive layer thereby resulting in a portion of thephotographed scene not being processed into a visible image. For example, if the film unit were camera with pressure-applying means, e.g., a pair of rollers, which are adapted to spread the processing composition ac'ross the film unit ina layer having an asymmetrical thickness as measured transversely of the film .unit with the minimum depth of the layer being located on that side of the film 'unit where'incomplete coverage of the photosensitive area by the composition is most likely to-occur."

One of the rollers, preferably the bottom roller, has

a generally symmetrical longitudinalcross section including opposite endportionswhich are adapted to engage longitudinally extending binding. elements of a film unit. The other roller, i.e., the top roller, includes collars at each end thereof which are adapted to engage the ends of the bottom roller for-providing a gap'of predeterminedminimum depth therebetween to facilitate entry of the-fiIm unit. The top roller also includes an intermediate film unit engaging portion having a length slightly less than the lateral'distance betweenthe binding elements and film unit engaging endlportions'located between each end of the intermediate portion and the collars. The aforementioned end portions of the top roller areadapted to cooperate with the opposite end portions of the bottomroller to engage the I binding elements ofthe film' unit as it passes therebetween to define the'depth of the layer of vprocessing composition to be spread across the photosensitive layer.

As stated above, if the exposed film unit enters the bite of the rollers in a canted orientation, a portion of the photosensitive layer of thefilrn unit may not be covered by the layer of processing composition. To provide for this contingency, one-of the end portions of the top roller is provided with a smaller diameter than the other end portion of the top roller, thus resulting in the longitudinally extending asymmetrically configured gap between thekrollers when a film. unit is passing therebetween. Also, the end portion of the top roller having the reduced diameter is located on the side of the roller assembly which first receives a portion of the leadingend of the canted or skewed filmunit because, it is usually the rear comer of the film unit located on the same side of thelongitudinal axis of the film unit as 1 that portion which .first enters the bite of the rollers where the aforementioned incomplete coverage of the photosensitive layer will occur. The asymmetrically configured gap between the rollers, which is a result of reducing the diameter of one of the end portions of the top roller, provides a structure wherein the depth of the layer of processing composition is thinner on that side of the film unit which first enters the bite of the rollers than on the other side of the film unit, i.e., the rollers spread the processing composition across the photosensitive layer of the film unit in a layer having an asymmetrical thickness, as measured in a direction transverse to the direction of movement of the film unit relative to the rollers. By spreading the processing composition in a thinner layer on the side of the film unit where the incomplete coverage is most likely to occur, the processing composition originally available on that side of the film unit is spread over a greater area of the photosensitive layer'before the composition becomes depleted. 1

In an alternative embodiment, the pressure-applying means preferably include a pair of rollers which define a gap through which an exposed film unit is adapted to be moved, and a torsion spring the'opposite ends of which are adapted to engage opposite ends of one of,

end, thereby asymmetrically loading the roller. When a film unit is located between the rollers, the asymmetrical loading produces an elongated asymmetrically configured gap between the rollers with the depth of the gap toward the end having the greaterforce being less than that at the other end, to producea layer of processing compositionhaving an asymmetrical thickness. The end of the roller having the greatest biasing force is adapted to spread the processing composition in a-thinner layer across that side of the film unit where the aforementioned incomplete spread is most likely to occur, thereby insuring complete coverage of the photosensitive area of the film unit.

cally configured gap for spreading a processing composition across a photosensitive layerof an exposed film unit as it is being advanced therethrough.

Another object of the invention is to provide pressure-applying means including a first member having a longitudinally extending, asymmetrically configured surface defining-one portion of a gap and a second member having a longitudinally extending, symmetrically configured portion defining a second portion of a gap. v

Another object of the invention is to asymmetrically bias at least one of a pair of pressure-applying members to provide a spread of processing composition of nonuniformthickness. t

Still another object of the invention is to provide pho asymmetrically spreading a processing composition across the film unit in a layer of non-uniform thickness.

Still another object of the invention is to provide a spreading assembly for spreading a processing composition across substantially the entire photosensitive area of an exposed film'unit whichwas originally moved into engagement with the spreading assembly in a skewed or possessing the construction, combination of elements In still another embodiment, the pressure-applying means preferably include a pair of juxtaposed rollers which cooperate with each other to define a gap having an asymmetrical configuration. One of the rollers, preferably the upper roller, has asubstantial'ly uniform diameter throughout a major portion thereof while the other roller has a substantially candlepin" configuration, i.e., its diameter gradually decreases from a maximum diameter intermediate its ends to a minimum diameter at or near its opposite ends. The configuration of the other roller is also asymmetrical in that its major diameter is closer to one end of the roller than the other end, and more specifically, is located closer to the end of the roller assembly which first receives a leading end portion of an exposed film unit. As in the embodiments previously described, offsetting the maxi- Another object of the invention is to provide a camera of the self-developing type with pressure-applying means having a longitudinally extending, asymmetriand arrangement of parts which are exemplified in the following detailed disclosure, and the. scope of the application of which will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS Fora fuller understanding of the nature and objects of the invention, reference should be had to. the following detailed description taken in connection with the accompanying drawings whereini FIG. 1 is a perspective view, partly insection, of photographic apparatus embodying the instant invention;

FIG. 4' is a diagrammatic end view of a film unit passing between the spreadrollersof the assembly shown in FIG-2;

FIG. 5 is a diagrammatic end view of a film unit passing between a pair of asymmetricallybiased spread rollers; and a FIG. 6 is a diagrammatic end view of a film unit passing between a pair of spread rollers of an alternative embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION Reference is now made to FIG. 1 of the drawings wherein is shown photographic apparatus in the form and shutter assembly. 24, a photocell 26 and an expoof the support member 94 with a generally U-shaped central portion lthereof extending around a lip 102 shown in FIG. 1 and a compact folded position, as is v more fully described in US. Pat. No .',3,678,83l.

Exposure chamber 12 is adapted to receive a film cassette 32 having an exposureaperture 34 in a forward wall 36, a resilient member 37 extending part way across an exit opening 38 in one end wall to prevent the passage of more than one film unit at a time therethrough and an elongated opening 40 in wall '36 which extends to the rear (to the left) of the cassette and part way down the rear endwall of the cassette. Positioned within cassette 32 are a plurality of film units 42 (see FIG. 3) which may .be of the type shown in US. Pat. No. 3,415,644. Each film unit 42 includes a leading end 44 having a. container or. pod 46 containing a processingcomposition '47 attached thereto, superposed image-receiving and photosensitive'layers positioned in alignment with opening 38, and a trailing end 50.

Camera further includes a motor 52.which may be powered by a battery locatedwithin cassette 32, a gear train 54 for operating various components of the camera including film-advancing means 56 having a cantiformedon 'the support member and seated against a' supporting surface 104 of that member. When the spring 96 is positioned on the support member 94 and f the support member connecteclto the bracket80 as indicated, an elongated projection 106 depending from the brackets flange portion 92 serves to retain the dlepin configuration, but rriay be cylindrical, has its fore relatively light in weight and of low inertia, being leveredmounted film engaging member 58, pressureapplying means including a pair of pressure-applying members or rollers 60 and 62drivingly coupled to the gear train 54 via gear 64, and an elongated member 66 for assisting in the movement of a pivotally mounted reflecting assembly 68.

Reflecting assembly68 includes a support70 having a planar mirror 72 mounted on one side thereof and an echelon type reflecting surface 74 on the other side. As is morefully described in U.S. Pat. No. 3,678,831, reflecting assembly 68 is adapted to be pivoted'between an exposure position adjacent a mirror 76 located on housing section 18 wherein light from lens 24 is reflected-by mirror 72 to expose the uppermost film unit closely adjacent cassette 32 wherein echelon'surface rotatably mountedon ashaft 108 by a pair of ball bearing assemblies 110. Opposite ends of theshaft 108 extend through

elongated slots

112 and 114 provided in the

ears

82 and 84 of the bracket 80. Flattened ends 116 and 118 of the torsion spring 96 seat in appropriately positioned annular recesses 120 of the shaft 108 so that the force of that spring continually urges the roller 60 towards itsupwardmost position within the

slots

112 and 114 as viewed-in FIG. 2. It will be noted that the support member 94 is configured with a pair of cutouts 121 to accommodateinitial loading of the spring 96 and subsequent displacement of its flattened ends -1 l6 and l 18 responsive to translatory movement of the shaft 108 along the

brackets slots

112 and 114.

Extensions 122 of the roller 62 are respectively journaled to the bracket .80 by ball bearing'assemblies 124 mounted in the

brackets cars

82 and 84. Provided on the roller 62 are a pair of spaced apart annular collars 126 against which the roller 60 is initially seated under 74 cooperates with lens 24, mirror 76 and viewing de- As indicated, the present invention isparticularly directed to certain aspects of the camers spreading assembly, the nature of which may best be understoodby now referring to FIG. 2 of the drawings. As shown therein, the assembly comprises a spread roll bracket 80 preferably formed from a unitary piece 'of sheet metal such as a stainless or carbon steelj Bracket 80 includes a pair of

upturned ears

82 and 84 joined together by a central portion 86 comprising a support 88 and spaced apart substantially

parallel flange portions

90 and 92. A rigid structural support member-94 is configured to seat against the support 88 intermediate the

ears

82 and 84 and nested between the

flange portions

90 and 92 of the bracket80. A pair of rivets 95 serve to secure the support member 94 to the bracket'80.. A specially configured'torsion spring 96 rests in tracks 98 the force of the torsion spring 96. These collars 126, de-

termine a controlled minimum gap between thesheetcontacting fa'cing surfaces 128and 1300f the rollers .60 and 62 which facilitates the initial introduction of a film unit therebetween. As the film unit 42 is introduced between the rollers and v62 (see FIG. 4) it effects a displacement of the roller 60 away from the roller 62 against theforce exerted on the roller 60 by the torsion spring 96. As the exposed film unit 42 is advanced between the

rollers

60 and 62,'the compressive force exerted thereon by same effects a spreading of the processirig composition from ,pod 46 in a layer across the photosensitive layer of the film unit. Preferably, the roller 62 is provided with a'pairof spaced apart annular recesses 132 strategically positioned as shownto receive selected portions of specially configured longitudin a1 edge bindings 134 of the film unit 42 in order to preclude the red-framing effect'in accordance with the teachings of US. Pat. No. 3,647,441 by Albert J. Bachelder entitled PHOTOGRAPHIC APPARATUS AND METHOD, issued'on Mar. 7, 1972.

In this unique arrangement, any frictional forces in the roller 60 shaft 108 assembly resulting from twisting or cocking of the bearing assemblies l1 0fare absorbed by the shaft 108 which is basically a 'nonrotating component. Thus, such frictional forces are .thereby reducing the load on that energy source. Most significantly, frictional forces of the roller assembly have been minimized by providing an arrangement wherein there is a non-rotating contact between the ends 116 and 118 of spring 96 and the shaft 108.

OPERATION After the photographer has focused the scene through the viewfinder 30, button 28 is depressed to initiate an exposure cycle. Subsequent to actuation of button 28, exposure chamber 12 is made lighttight by closing shutter 24 and the viewfinders entrance pupil l1 1. Motor 52 is energized to move reflecting assembly 68 to the up or exposure position. Motor 52 is then stopped and the shutter opened and closed to expose the forwardmost film unit 42 in cassette 32. Motor 52 is again' started to drive gear train 54 to move member 8 I I right side thereby resulting in the composition on the left side being depleted before the corner area 153 of the film unit has been covered by the processing com- 66 to the left, as viewed in FIG. 1, thereby returning refleeting assembly 68 to the viewing position and to actuate film-advancing means 56. Actuation of the filmadvancing means moves the film engaging member 58 into contact with the trailing edge 50 of film unit 42 to move the film unit out of itsexposure position and into the bite of the

rotating rollers

60 and 62 via exit opening 38 in cassette 32. It should be noted that the film engagingmember 56 engages the film unit on one side of its'longitudinal axis, indicated as 115 in FIG. 3. En gaging and moving a film unit in this manner may result in the film unit being canted as it is about to enter the bite of

rollers

60 and 62 as shown in FIG. 3. Canting of the film unit 42 is possible because usually its width'is slightly less than the width of the interior of cassette 32.

Should the film unit enter the bite of

rollers

60 and 62 in a canted condition, a spread pattern similar to that position. Obviously, this type of a spread will not produce a visible image in area 153.

The present invention substantially obviates this problem by constructing thespreading assembly such that it spreads the processing composition in a thinner layer on the left side of the film's longitudinal axis 115 than on the right thereby increasing the area that can be covered by the processing composition on the left side. Specifically, this is accomplished by providing the left end portion 127 of roller 62 with a diameter less than that of intermediate section 130 (asbest seen in FIG. 2a) and right end portion 129, the latter two having substantially the same diameters. As shown in FIG. 7

and configuration between the sheet-contacting

surfaces

128 and 130 of

rollers

60 and 62. Providing the left end portion 127 of roller 62 with a smaller diameter than that of right end portion 129 results in the left hand portion as viewed in FIG. 4) of sheet-contacting surface 1'30 extending further into opening 48 in film unit 42 than the'right hand portion of, surface 130, thereby providing a gap between

surfaces

128 and 130 having a longitudinally extending, asymmetrical configuration for spreadingthe processing composition in a layer having an asymmetrical thickness as measured shown by the

lines

140, 142, 144, 146, 148, 150 and i 152 in FIG. 3 may be produced. These lines represent progressive stages of the advancing edge of the processing composition during spreading of thecomposition.

For example, where pod 46 is comprised'of three segments, as shown in FIG. 3, initial rupturing of the pod 46 by

rollers

60 and 62 presents an advancing wave front as shown at 140. As the film unit continues to move through the

rollers

60 and 62 the major portion of the wave front progressively flattens out while the created as a result of the acute angle between a line containing the discharge end 49 of pod 46, which is perpendicular to the longitudinal axis 115, and a plane containing the longitudinal axes of the rollers. Lateral movement of the'processing composition to the right may result in the left. side of the wave receding relative to the remainder of the wave front until you reach a condition as shown at 152 where substantially the entire photosensitive area of the film unit has been covered with processing composition except for area 153. In other words, it appears that the amount of composition originally providedfor covering the left half of the film unit is gradually reduced by the movement of the composition from the left side of the'film unit to the transversely of the direction of movement of the film unit relativeto the rollers. Stated'another way, reducing the diameter of left end portion 127 allows the left end of roller to move closer to-the left end of roller 62, thereby resulting in roller 60 being slightly canted off its horizontal axis relative to the horizontal axis 131 of top roller 62 when a film unit is passing between the rollers. In practice, it has been found that where the diameter of sheet-contactingportion 130 of roller 62 has adiameter of approximately .250 inches, a diameter of approximately .2496 inches for left end' portion 127 is sufficient to substantially obviate the aforementioned 1 ,45 problem of incomplete coverage, of the film unit's pholeft side of the wave trails behind, as shown from 146 I tosensitive layer by the processing composition. While the present invention, including all of its embodiments, provides for spreading the processing composition in a layer of non-uniform thickness, it should be realized that the depth or thickness of the layer of composition on each side of the film units-longitudinal axis within the limits necessary to initiate development and form the desired photographic image. For example, in a film unit of the type described, the thickness-of the layer of processing composition may be between .002 and .003 inches. Thinning out the thickness of the layer of processing composition on the left side of the film unit by approximately .0001 inch relative to the right side of the film unit is generally sufficient to obtain complete coverage of area 153.

Reference is now made to FIG. 5 wherein an alternative embodiment of the invention is depicted. In this embodiment roller 62' is similar to roller 62 except that the left side of shaft 108 (as viewed in FIG. 2) with a spring load of 4.75 lbs. and the right side of the'shaft with aload of 3.75 lbs. provides a spread which com-,

pletely covers a picture area (defined by opening 48) of approximately 3.1 inches square when the pod contains 800 milligrams of processing composition. The asymmetrical biasing of shaft 108 and roller 60 is accomplished' by originally forming the end 1.16 of spring 96-at an angle relative to end 118, as shown at 116' in FIG. 2, such that after assembly of the spreader assembly, the end of spring96 having end 116 located in position 116' will be under greater compression than the opposite end of the spring, thereby providing a greater load on the end of shaft 108 which is closest to the drive side of thespreader assembly, i.e., the left side as viewed in FIGS. 2-6. As best seen in FIG. 5, when a film unit enters the bite of

rollers

60 and 62, roller 60 ismoved away from roller 62'. As the film unit enters between the rollers, the gap therebetween changes to an asymmetrical configuration with the minimum depth of the gap being on the left side of the roller assembly. Accordingly, when the rollers rupture pod 46, the processing composition 47 which was contained in the pod closest to the left side'of the film unit is spread in a thinner layer across the photosensitive area, therebyenabling the composition to be spread over a greater area, i.e., the entire area defined by opening 48.

Reference is now made to FIG. 6 wherein stillanother embodiment of the inventionis illustrated. In this embodiment thespreading assembly includes a top roller 62' and the bottom roller 60' mounted for' rotation about parallel axes 131 and-13s. Roller 60 is adapted tocooperate with roller 62 to' define a longitudinally extending (from end-to-end of therollers) asymmetrically configured gap therebetween when a film unit is located between the rollerspspecifically, roller 60 is provided with a candlepin configuration having a major diameterat 160 which gradually decreases to similar minor diameters near its

ends

162 and 164. It should be noted that the major diameter 160 is located offcenter, 'i.e., it is closer to end 162 than end 164,

thereby decreasing the thickness of the processing 45 composition 47 on the left side of the spreading assembly relative to the right side. As in the previous embodimerits, rollers 60 and 62'- cooperate with each other to spread the processing compositionv across a photosensitive layer of the film unit in a layer having an asymmetrical thickness, as measured in a directiontransverse to the direction of movement of the filmrelative to the rollers, with the minimum thickness of the layer being located on that side of bite of the rollers.

Since certain changes may, be made in the above apparatus without departing from the scope of the invention herein involved, it is intended that all matter conthe film which first enters the of the exposed film unit in a layer having an asymmetrical thickness, as measured in a plane transverse'to the direction of movement of the film unit relative to .said pressure-applying means, said pressure-applying means including means defining a longitudinally extending,- asymmetrically configuredgap when the film unit is being advanced therebetwee'n, said gap tapering from' a maximum thickness at one end toa minimum thickness at a point more than halfway toward its opposite end be engaged by a leading edge of the exposed 'filmunit before or at the time that said one'end ofsaid gap is engaged by the leading end of the exposed film unit.

3. Photographic apparatus for spreading a processing composition acrossa photosensitive layer. of an exposed film unit comprising:

pressure-applying means adapted to engage opposite sides of an exposed film unit for spreading a pro cessing composition across a photosensitive layer of the exposed film unit in a layer having an asymmetrical thickness, as measured in a plane transverse to the direction of movement of the film unit relative to said pressure-applying means, said pressure-applying means including means defining a longitudinally extending, asymmetrically configured gap when the film unit is being advanced therebetween, said gap tapering from a maximum thickness at one end to a minimum thickness at a location less than one half of the distancebetween opposite ends of said gap. 4. Photographic apparatus as defined in claim 3 wherein said one end of said gap is adapted to be engaged'by a leading edge of .the exposed filmunit at or t after the time that the'oppositeendof saidgap is engaged by the leading end of the film unit.

5. Photographic apparatus as defined claim- 4 wherein said pressure-applying means includes first and second rollers, said first roller having'film unit engaging surfaces including first and second end'portions and an intermediate portion having a maximum diameter nonuniformly spaced .from said first and second end portions.

6. Photographic apparatus as defined claim 5 wherein said second roller includes film unit engaging portionshavi-ng similar diameters. A

Photographic apparatus as defined in claim 6 wherein said film unit engaging portions of said second roller include an intermediate'po'rtion and first and second end portions, said second roller further including a recess located adjacent each end of said intermediate portion of said second roller and said first and second end portions of said'second roller.-

8.-Photographic apparatus as definedin claim 7 further including means for establishing a predetermined minimum spacing between said first and second rollers.

ingcomposition across a photosensitive layer of an exposed film unit comprising:

' pressure-applying means including a first roller-having a longitudinally extending symmetrically configured film engaging portion and a second roller having film unit engaging surfaces including first and second end portions, said first and secondrollers being adapted to engage opposite sides of an exposed film unit for spreading a processing composition across a photosensitive layer of the exposed film unit in a layer having an asymmetrical thickness, as measured in a plane transverse to the direction of movement of the film unit relative to said pressure-applying means, said pressureapplying means defining a longitudinally extending, asymmetrically configured gap when the film unit is being advanced therebetween, said .gap tapering from a maximum thickness at one end to a minimum thickness at a point'more than halfway toward its opposite end, said opposite end of said gap being positioned to be engaged by a leading edge of the exposed film unit before or at the time that said one end of said gap is engaged by the leading end of the exposed film unit, said first end portion being located near said opposite end of said gap and having a diameter less than that of said second end portionl l1. Photographic apparatus as defined in claim wherein said second roller includes an intermediate film unit engaging portion located between said first and second end portions, said intermediate film unit engagingportion having a diameter substantially the same assaid second-end portion. a

l2. Photographic apparatus as defined in claim 11 wherein said second roller .further includes a recess located adjacent each end of said intermediate film unit exposed film unit therebetween.

l4. Photographic apparatus as defined in claim 10 further including means for resiliently biasing one of said said first and second rollers toward the other.

15. Photographic apparatus for spreading a process: 7

ing composition'in a layer between a pair of elements,

at least one of which forms part of a film unit, said apparatus comprising:

pressure-applying means including first and second means adapted to define an elongated gap throughwhich a film unit is adapted to be moved;

means for mounting said first and second means for relative movement toward and away from each other; and I means for applying an asymmetrical biasing force to one of said first and second meansduring spreading of a processing composition across a photosensitive layer of the film unit, whereby said first and second means spreads the processing composition in a layer of non-uniform thickness.

16. Photographic apparatus as defined in claim 15 wherein said first means is a roller assembly having opposite end portions and said biasing means is mounted for engagement with at least one of said end portions.

18. Photographic apparatus as defined inclaim 17 wherein said biasing means. is a torsion spring having opposite ends adapted to engage saidend portions of said roller assembly.

l9. Photographic apparatus as-defined in claim 18 wherein said opposite end portions of said roller assembly comprise substantially non-rotatablepor tions of said roller assembly, whereby frictional losses between said opposite ends of said torsion spring and said opposite end portions of said rollerassembly are substantially eliminated. l

20. Photographic apparatus comprising:

means for supporting a film unit having a longitudinal axis in position for exposure;'

means for engaging the film unit on one side of the longitudinal axis and moving the film unit out of the exposure position subsequent to exposure; and

dinally extending, asymmetrically configured gap when the film unit is being advanced therebetween,

.said gap tapering from a maximum thickness at one end to a minimum thickness at a pointmore than halfway toward its opposite end.

21. Photographic apparatus as-defined in claim'20 wherein said pressure-applying means includes first and second rollers.

22. Photographic apparatus as defined inclaim 21 wherein said first roller includes a film unit engaging portion having a substantially longitudinally extending symmetrical configuration and said second roller includes film unit engaging portions of different diameters.

23. Photographic apparatusas defined in claim 22 further including means for biasingone of said first and second rollers toward the other. a l

24. Photographic apparatus as defined in claim 21 diameter located closer to one end of said film unit engaging portion than to its opposite end and said second roller includes film unit engaging portions of substantially identical diameters. l

25. Photographic apparatus as defined'in claim 24 further including means for biasing one of said first and second rollers toward the other.

26. Photographic apparatus comprising: means for supporting a film unit having a longitudinal axis in position for exposure; means for engaging the film unit on oneside of the longitudinal axis and moving the film unit out of the exposure position subsequent to exposure; pressure-applying means mounted in position to receive'the exposed film unit as it moves away from the exposure position, said pressure-applying means including first and second means adapted to define an elongated gap through which the film unit is adapted to be moved;

means for mounting said first and second means for relative movement toward and away from each other; and

means for applying an asymmetrically biasing force to one of said first and second means to spread a processing composition across a photosensitive layer of the film unit, said asymmetrical biasing force being greatest on the longitudinal side of the film unit engaged by said means for engaging, whereby said pressure-applying means spreads the processing composition ina layer of non-uniform thickness.

27. Photographic apparatus as defined in claim 26 wherein said first means is a roller assembly having opposite end portions and said biasing means is mounted for engagement with at least one of said end portions.

1 said roller assembly, whereby frictional losses between saidopposite end of said torsion spring and said opposite end portions of said roller assembly are substan tially eliminated.

31. Photographic apparatus for use with a film unit having leading and trailing edges. interconnected by spaced side edges and a container of processing composition located adjacent the leading edge which is adapted to be ruptured prior to spreading the processing composition across a photosensitive, layer of the film unit and toward the trailing edge, comprising:

unit.

means for locating the film unit in position for exposure; means forengaging the film unit ing movement to the film unit as it is advanced out of the exposure position, subsequent to exposure; and pressure-applying means for spreading the processing composition across the photosensitive layerin'a layer having an asymmetrical thickness as measured in a plane transverse to the direction of movement of the exposed film unit relative to said pressure-applying means, said pressure-applying means including means adapted to define a longitudinally extending, asymmetrically configured gap when the film unit is being advanced therethrough.

32. Photographic apparatus as defined in claim 31 wherein said gap tapers from a maximum depth near one end to a minimum depth near its opposite end.

33. Photographic apparatus as defined in claim 32 wherein said opposite end of said gap is adapted to be engaged by a portion of the leading edge of the exposed film 'unit located adjacent the oneside edge before or at the time that said one end of said gap is engaged by a portion of the leading edge of the exposed film unit located adjacent the other side edge of the exposed film 34. Photographic apparatus as defined in claim 31 I wherein said gap tapers from a maximum depth at one end to a minimum depth at a point more than halfway towardits opposite end.

3S. Photographic'apparatus as defined in claim 34 wherein said-opposite end of said gap is adapted to be I at its trailing edge adjacent one of the side edges for applying a cant-

Claims

1. Photographic apparatus for spreading a processing composition across a photosensitive layer of an exposed film unit comprising: pressure-applying means adapted to engage opposite sides of an exposed film unit for spreading a processing composition across a photosensitive layer of the exposed film unit in a layer having an asymmetrical thickness, as measured in a plane transverse to the direction of movement of the film unit relative to said pressure-applying means, said pressure-applying means including means defining a longitudinally extending, asymmetrically configured gap when the film unit is being advanced therebetween, said gap tapering from a maximum thickness at one end to a minimum thickness at a point more than halfway toward its opposite end.

2. Photographic apparatus as defined in claim 1 wherein said opposite end of said gap is positioned to be engaged by a leading edge of the exposed film unit before or at the time that said one end of said gap is engaged by the leading end of the exposed film unit.

3. Photographic apparatus for spreading a processing composition across a photosensitive layer of an exposed film unit comprising: pressure-applying means adapted to engage opposite sides of an exposed film unit for spreading a processing composition across a photosensitive layer of the exposed film unit in a layer having an asymmetrical thickness, as measured in a plane transverse to the direction of movement of the film unit relative to said pressure-applying means, said pressure-applying means including means defining a longitudinally extending, asymmetrically configured gap when the film unit is being advanced therebetween, said gap tapering from a maximum thickness at one end to a minimum thickness at a location less than one half of the distance between opposite ends of said gap.

4. Photographic apparatus as defined in claim 3 wherein said one end of said gap is adapted to be engaged by a leading edge of the exposed film unit at or after the time that the opposite end of said gap is engaged by the leading end of the film unit.

5. Photographic apparatus as defined in claim 4 wherein said pressure-applying means includes first and second rollers, said first roller having film unit engaging surfaces including first and second end portions and an intermediate portion having a maximum diameter non-uniformly spaced from said first and second end portions.

6. Photographic apparatus as defined in claim 5 wherein said second roller includes film unit engaging portions having similar diameters.

7. Photographic apparatus as defined in claim 6 wherein said film unit engaging portions of said second roller include an intermediate portion and first and second end portions, said second roller further including a recess located adjacent each end of said intermediate portion of said second roller and said first and second end portions of said second roller.

8. Photographic apparatus as defined in claim 7 further including means for establishing a predetermined minimum spacing between said first and second rollers.

9. Photographic apparatus as defined in claim 5 further including means for rEsiliently biasing one of said first and second rollers toward the other.

10. Photographic apparatus for spreading a processing composition across a photosensitive layer of an exposed film unit comprising: pressure-applying means including a first roller having a longitudinally extending symmetrically configured film engaging portion and a second roller having film unit engaging surfaces including first and second end portions, said first and second rollers being adapted to engage opposite sides of an exposed film unit for spreading a processing composition across a photosensitive layer of the exposed film unit in a layer having an asymmetrical thickness, as measured in a plane transverse to the direction of movement of the film unit relative to said pressure-applying means, said pressure-applying means defining a longitudinally extending, asymmetrically configured gap when the film unit is being advanced therebetween, said gap tapering from a maximum thickness at one end to a minimum thickness at a point more than halfway toward its opposite end, said opposite end of said gap being positioned to be engaged by a leading edge of the exposed film unit before or at the time that said one end of said gap is engaged by the leading end of the exposed film unit, said first end portion being located near said opposite end of said gap and having a diameter less than that of said second end portion.

11. Photographic apparatus as defined in claim 10 wherein said second roller includes an intermediate film unit engaging portion located between said first and second end portions, said intermediate film unit engaging portion having a diameter substantially the same as said second end portion.

12. Photographic apparatus as defined in claim 11 wherein said second roller further includes a recess located adjacent each end of said intermediate film unit engaging portion and between said first and second end portions.

13. Photographic apparatus as defined in claim 12 further including means for establishing a predetermined minimum spacing between said first and second rollers to facilitate the entry of the leading edge of the exposed film unit therebetween.

14. Photographic apparatus as defined in claim 10 further including means for resiliently biasing one of said said first and second rollers toward the other.

15. Photographic apparatus for spreading a processing composition in a layer between a pair of elements, at least one of which forms part of a film unit, said apparatus comprising: pressure-applying means including first and second means adapted to define an elongated gap through which a film unit is adapted to be moved; means for mounting said first and second means for relative movement toward and away from each other; and means for applying an asymmetrical biasing force to one of said first and second means during spreading of a processing composition across a photosensitive layer of the film unit, whereby said first and second means spreads the processing composition in a layer of non-uniform thickness.

17. Photographic apparatus as defined in claim 16 wherein said biasing means is mounted for engagement with both of said end portions.

18. Photographic apparatus as defined in claim 17 wherein said biasing means is a torsion spring having opposite ends adapted to engage said end portions of said roller assembly.

19. Photographic apparatus as defined in claim 18 wherein said opposite end portions of said roller assembly comprise substantially non-rotatable portions of said roller assembly, whereby frictional losses between said opposite ends of said torsion spring and said opposite end portions of said roller assembly are substantially eliminated.

20. Photographic apparatus comprising: means for supportIng a film unit having a longitudinal axis in position for exposure; means for engaging the film unit on one side of the longitudinal axis and moving the film unit out of the exposure position subsequent to exposure; and pressure-applying means adapted to engage opposite sides of the exposed film unit for spreading a processing composition across a photosensitive layer thereof in a layer having an asymmetrical thickness, as measured in a plane transverse to the direction of movement of the exposed film unit relative to said pressure-applying means, said pressure-applying means including means defining a longitudinally extending, asymmetrically configured gap when the film unit is being advanced therebetween, said gap tapering from a maximum thickness at one end to a minimum thickness at a point more than halfway toward its opposite end.

21. Photographic apparatus as defined in claim 20 wherein said pressure-applying means includes first and second rollers.

22. Photographic apparatus as defined in claim 21 wherein said first roller includes a film unit engaging portion having a substantially longitudinally extending symmetrical configuration and said second roller includes film unit engaging portions of different diameters.

23. Photographic apparatus as defined in claim 22 further including means for biasing one of said first and second rollers toward the other.

24. Photographic apparatus as defined in claim 21 wherein said first roller includes a film unit engaging portion of candlepin configuration with its maximum diameter located closer to one end of said film unit engaging portion than to its opposite end and said second roller includes film unit engaging portions of substantially identical diameters.

25. Photographic apparatus as defined in claim 24 further including means for biasing one of said first and second rollers toward the other.

26. Photographic apparatus comprising: means for supporting a film unit having a longitudinal axis in position for exposure; means for engaging the film unit on one side of the longitudinal axis and moving the film unit out of the exposure position subsequent to exposure; pressure-applying means mounted in position to receive the exposed film unit as it moves away from the exposure position, said pressure-applying means including first and second means adapted to define an elongated gap through which the film unit is adapted to be moved; means for mounting said first and second means for relative movement toward and away from each other; and means for applying an asymmetrically biasing force to one of said first and second means to spread a processing composition across a photosensitive layer of the film unit, said asymmetrical biasing force being greatest on the longitudinal side of the film unit engaged by said means for engaging, whereby said pressure-applying means spreads the processing composition in a layer of non-uniform thickness.

28. Photographic apparatus as defined in claim 27 wherein said biasing means is mounted for engagement with both of said end portions.

29. Photographic apparatus as defined in claim 28 wherein said biasing means is a torsion spring having opposite ends adapted to engage said end portions of said roller assembly.

30. Photographic apparatus as defined in claim 29 wherein said opposite end portions of said roller assembly comprise substantially non-rotatable portions of said roller assembly, whereby frictional losses between said opposite end of said torsion spring and said opposite end portions of said roller assembly are substantially eliminated.

31. Photographic apparatus for use with a film unit having leading and trailing edges interconnected by spaced side edges and a container of processing composition located adjacent The leading edge which is adapted to be ruptured prior to spreading the processing composition across a photosensitive layer of the film unit and toward the trailing edge, comprising: means for locating the film unit in position for exposure; means for engaging the film unit at its trailing edge adjacent one of the side edges for applying a canting movement to the film unit as it is advanced out of the exposure position, subsequent to exposure; and pressure-applying means for spreading the processing composition across the photosensitive layer in a layer having an asymmetrical thickness as measured in a plane transverse to the direction of movement of the exposed film unit relative to said pressure-applying means, said pressure-applying means including means adapted to define a longitudinally extending, asymmetrically configured gap when the film unit is being advanced therethrough.

33. Photographic apparatus as defined in claim 32 wherein said opposite end of said gap is adapted to be engaged by a portion of the leading edge of the exposed film unit located adjacent the one side edge before or at the time that said one end of said gap is engaged by a portion of the leading edge of the exposed film unit located adjacent the other side edge of the exposed film unit.

34. Photographic apparatus as defined in claim 31 wherein said gap tapers from a maximum depth at one end to a minimum depth at a point more than halfway toward its opposite end.

35. Photographic apparatus as defined in claim 34 wherein said opposite end of said gap is adapted to be engaged by a portion of the leading edge of the exposed film unit located adjacent the one side edge before or at the time that a portion of the leading edge of the exposed film unit located adjacent the other side edge engages said one end of said gap.