US2928329A

US2928329A - Photographic developing machine

Info

Publication number: US2928329A
Application number: US621363A
Authority: US
Inventors: David R Limbach
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-11-09
Filing date: 1956-11-09
Publication date: 1960-03-15
Anticipated expiration: 1977-03-15

Description

March 15, 1960 D. R. LIMBACH 2,928,329

PHOTOGRAPHIC DEVELOPING MACHINE Filed Nov. 9, 1956 s Sheets-Sheet 1 INVENTOR. DA W0 8. L/MBA CH MYMJ ATTORIVE XS.

Ma h 15, 19 D. R. LIMBACH 2,928,329

PHOTOGRAPHIC DEVELOPING MACHINE 3 Sheets-Sheet 2 Filed Nov. 9, 1956 E! .3 *w b w m 2 TN Nv nv PLWUI a 5 n .N 3 .mn m E a J 3 x .Q R Q n .0 m #nl Q 0- 2 m 2 2 Q h 2 I W 9.

3 mm mm mm mm R k 1 1 1 in 5 Q 8 ow 2 & Q Q 3 E n JNVENTOR. DA V/D R. L INBA (H BY OMOLMJL A T 7' GEN X March 15, 1960 D. R. LIMBACH PHOTOGRAPHIC DEVELOPING MACHINE 3 Sheets-Sheet 5 Filed Nov. 9, 1956 INVENTOR.

H M c E M U mm 2 A w N% PHOTGGRAPHIC DEVELOPING MACHINE David. R. Limbach, Flint, Mich. Application November 9, 1956, Serial No. 621,363

15 Claims. or. 95-44 This invention relates as indicated to continuous photographic developing machines and, more particularly, to the film handling and conveying means employed therein.

' In conventional machines of this type, the films to be processed are manually secured to detachable hangers and these, in turn, are attached to and removed from conveying elements which carry the same through the machine. This, of course, requires a separate and large supplyof hangers to be kept on hand and, furthermore, necessitates a fairly complicated structural arrangement 'to provide the desired rapid loading while, at the same tinuous developing and drying of films with a greatly reduced minimum of work and attention on. the part of an operator.

It is another object of the invention to provide such a machine wherein the films are automatically picked up by a conveyor, conveyed successively through the necessary tanks of solutions and through a drier, and automatically discharged from the machine;

It is a further object of my invention to provide improved means for securing the films to such conveyor such means simplifying the loading steps and ensuring that the films will remain properly attached until ready for discharge.

It is another important object of this invention to provide a photographic developing machine in which the hangers which secure the films to the conveyor are permanently fixed to the latter, thereby to eliminate completely the need, expense and inconvenience of the detachable hangers used heretofore.

It is another object of this invention to provide a photographic developing machine which does not require the usual water jackets for'the solution tanks and related temperature controls, thereby to simplify and reduce the cost of construction.

Additional objects are to improve the dryer section of the machine, once again with especial regard to reducing the time required, and to provide a machine which is in overall construction comparatively simple and inexpensive to supply and maintain.

Other objects and advantages of the present invention will become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed draw- United States s a e an extensionof the work path through the tanks. 1 to 8.. I

age

in longitudinal section;

Fig. 2 is a top plan view of the machine illustrated in Fig. 1;

Fig. 3 is a side elevation showing on an' enlarged scale the mechanism whereby the films are fed to the machine and attached to the conveyor means therewithin;

Fig. 4 is a fragmentary view of a chain employed. as part of such conveyor means, said chain carrying elements for attachment of the film;

Fig. 5 is a sectional View taken along the line 5-5 in Fig. 4;

Fig. 6 is a detailed view in side elevation illustrating stripper mechanism, partially broken away, for removing the films from the conveyor and discharging them from the machine;

Fig. '7 illustrates in section a valve employed in the machine for supplying the same with the various liquids used in the developing of the films;

Fig. 8 is a view taken on the Fig. 7; e

Fig. 9 is a side view of an alternative form of preliminary drying means which may be employed in lieu of that incorporated in' the Fig. 1 construction;

Fig. 10 is a sectional view of the'Fig. 9 device taken on the plane of the line 10-40 therein; and

Fig. 11 is a detailed cross-sectional view of the machine of Fig. 1 taken along the line Ill-11.

Referring now to the drawings in detail, and particularly to Figs. 1 and 2, the illustrated machine comprises a developer section including a plurality of upright tanks for holding the various solutions conventionally employed adjoining, with adjacent wall 9, and extending centrally into each tank from the top of the machine'there. is a divider plate 19. Such plates lil, as will appear more fully hereinafter, prevent films simultaneously entering and leaving the same tank from coming into contact with one another. Each of the tanks has a circular bottom 9' and attached to the tanks 1, 3, and 5 are contact heaters 149. V

The tanks are of the indicated varying depth to provide predetermined different periods of immersion offilm moved continuously and successively therethrough- A large closed drying chamber is located immediately to the right or at the exit end of the developer section, the same being defined primarily by a side wall 11, a top wall 12, a bottom wall 13 spaced above the. actual base of the machine, and a vertical wall 14; The latter, broken away for convenience of illustration in Fig. 1, is spaced inwardly a slight distance from the opposite side wall of the chamber. The space within such bounds is interrupted by a series of alternating'upper and lower vertical bafiies 15 transverse thereof and overlapping in opposed projection to define a sinuous passage which. is

Mounted in the bottom of the drying chamber, between each pair of'the lower bafiles 15, is a blower" 16 arranged to draw, air from the bottom region of thechambcr and Patented Mar. 15, 1960 plane of the line 88 in ing chamber.

force it upwardly between the intermediate wall 14 and the adjacent side 17 of the machine, as shown by the arrows. The wall 14 on the outer side thereof and above the blowers 16 supports a heating element 18. It will be noted from Fig. 1 that top wall12 is upwardly offset .above the upper edge of the wall 14, so that air flowing across and warmed by the heater 18 moves into this upper manifold and then downwardly through the drytype is inserted in the intake air flow to the blowers to reduce the moisture content of the air and hence substantially reducethedrying time. iAn inlet passageway ets 31' therein, up over the sprockets 20 on the roller 191 between the tanks 1 and 2, and in similar manner through A dehumidifier of any suitable available.

18a is provided in the lower part of the drying chamber at the right and an exhaust passageway 18b in the-upper part of the drying chamber at the left so that freshair is continually'circulated. through the drying chamber.

The movement of air from the intake 18a in the right to the exhaust 1812 in the left coupled with the movement of the air in a vertical circular path induced by the blowers 16, causes the air to move in a generally helical path from right to left through the drying chamber.

Returning now to the'developer section, a transverse roller 19 having sprocket wheels 20., at the respective ends thereof is supported above the left wall of each tank. The several such rollers 19 and wheels 20 are fixed on shafts 21 journalled in brackets 22 projecting from'the frame of the machine, and extending the length of' the latter there is a horizontal driven shaft 23 mounted in journals 24 and having a sprocket wheel 25 thereon near Sprocket shaft 23. a

In the bottom'of each of the tanks 1 through8, stradtheir endless paths only by means of the sprockets 20 then pass down into the tank 1 and over the idler sprockall of the subsequent tanks. From the sprockets 31 in the bottom of the tank 8 the chains extend upwardly over the sprockets 32 in the left hand end of the drying chamber, then downwardly, about the left hand pair of sprockets'33, and upwardly over the next pair of sprockets 32. In such fashion the chains pass through the drying chamber until they emerge therefrom over the right hand pair of sprockets 32. From the sprockets 32 they extend downwardly over the sprockets 43 at the left side thereof and over the right sides of the sprockets 36.

From the sprockets 36 they proceed over the sprockets 37 and back to the sprockets 39.

It will be noted that the chains are driven through on the rollers 19 which are rigidly connected to their axles 21. The sprockets 43 associated with the roller 41 are permitted to slip on their axle, and the remaining sprockets'in the machine are merelyidlers which fix the. pathsiof the chains without enforcing movement on them.-

1 A number of cross rods 50 are connected to and be tween the chains in spaced relation along the same, with their ends supported, as shown in Figs. 4 and 5, by U-shaped clips 51 secured to the chains by rivets .52. The clips 51 are provided with holes 53 through which the rod ends rotatably extend, and a cotter pin .54 is passed through each end within the assocated clip. Each rod 50 has a plurality of spaced hooks fixed thereto of the form illustrated most clearly in Fig. 3.

With further particular reference to this figure, the roller 39 is provided with a plurality of circumferentially extending axially spaced slots 56 which are so positioned as to receive the books 55 on the rods 50. A .cam 57 is secured to the frame of the machine by a support dling the plate '10 therein, there is a cross rod 31 a which carries a pair ,of idler sprockets 31 spaced apart a distance equal to the spacing of the sprockets 20 on the rollers 19. The ends of rods 31 extend through fluid seals in the sides of the tanks or, alternatively, they can be mounted in frames extending from the bottom edges of the plates 10. Similarly, idler sprockets in two series 32 and 33 are provided in the drying chamber. The sprockets 32 are mounted on stub shafts 34 in the upper portion of the chamber, while sprockets 33 are in the lower portion, respectively below the bottom edges of baflies 15, on like shafts 35. The sprockets in each series are arranged in pairs,'with one at each side of the drying chamber, separated by the same distance as. sprockets 7 20 in the developer section. They arefurthermore grouped in units of two at every occurrence, on parallel horizontal axes as shown. correspondingly laterally spaced sprockets 36 are rotatably supported below the last upper sprockets 32, adjacent the rear wall of the machine and spaced longitudinally along the lower portion thereof, below the drying chamber and tanks, are sprocket pairs 37.

At the left end, the feed end of the machine, and at approximate waist height, there are two vertically spaced rollers 38 and 39, each of which is equippedwith a pair of sprockets 39'. At the right end of the machine, which is thedischarge end, there are two rollers 4t) and 41.

The roller 41 is secured to a shaft 42 which is journalled to the frame of the machine, while a pair of sprockets 43 are rotatably mounted on this shaft. The latter also carries a gear 44 which engages with a worm 45 on the drive shaft 23, as illustrated in greater detail in Fig. 6.

I Extending throughout the machine are two endless chains 49 of the roller type, as shown in Fig. 4, respectively engaged about the two groups of sprockets at the i In more detail, the chains extend sides of the machine. between the sprockets 39' on the rollers 38 and 39 and -up over the'sprockets 20.0n the left hand roller 19." They the cam to be moved in apath generally parallelto the nearesttangent to the roller 39. A horizontal plate 60 is mounted on the machineby means of a support 61 and extends to a point closely adjacent to the roller 39 at the side thereof from which the chains 49 approach in their movement. This end of the plate 60 carries anupwardly extending stop. 62, and a plate 63 is supported just above the plate 60 by bolts 64. The edge 'ofth'e plate 63 remote from the chains 49 is turnedupwardly away from the plate 60, while both such plates are provided with slots which permit the hooks 55 to' pass through them.

When a film-66 is to be attached'to the conveyor for processing, it is placed on the plate 60 and inserted into the space between the plates 60 and 63 until it contacts the stop 62.- This is the only-motionthe operator of the machine must make to load the film intothe machine, for

the chains moving upwardly draw the hooks 55 of one of the rods 50 against the cam 57. {Further movement ofsuch hooks 55 forcesthemto enter the slots 65 .in the plates 60 and 63 and puncture the film. 66. Asthe rod continues its advance, the cam 57 forces'the hooks '55 into the slots 56 in the roller 39. This movement of the hooks 55'forces the film to move on the latter down to the vertices 67 thereof. The chains then move the rod 50 on through the machine, and the hooks carry 'the film 66 therewith- It should be noted that the plate 63 does not extend as far to the'right in Fig. 3 asdoes the plate i the position of the cam 57. The cam is maintained in such position that the hooks will pierce the film along a line closely adjacent to the edge of the film, bummeciently far from the edge so that the film will .nottear side of the film which acts as a liquid cushion holding the film away from the walls. The distance between the end walls or" the tanks and the plates is just large enough that the books 55 cannot catch on thesame regardless of the position to which the rod 5% may rotate.

However, this distance is maintained small enough thatif, for any reason, the chain-is stopped while a film is above the rod 5% in one of the tanks, the weight of the film will not rotate the hooks around so that the film .hangs below the hooks; instead the film will lean against one of the end walls of the tank or against the plate 10.

Two rollers, 68 and 68a respectively, are located on opposite sides of the path of the film as it rises out of the tank 8. As illustrated in greater detail in Fig. '11, the rollers 68 and 68a are mounted in journals 63b and 680 respectively. The journals 630 are rigidly mounted on support plates odd which are connected to the frame of the machine. The plates 63!! carry flanges 68f thereon, and springs 68g are compressedbetween the flanges 68) and the journals 68b, holding the two rollers together under a predetermined force. The rollerob is provided with a plurality of circumferentially extending grooves 68h therein which receive the hooks 55 preventing damage to either the hooks or the rollers The surfaces of the roller 68 between the grooves 68h are concave, that is, having the shape of the radially inward portion of a torus. The roller 68 is made of a resilient material such as neoprene rubber, and the pressure of the springs 6Sg-;is suflicient that they force the concave portions of the roller 68 flat along the line of contact between the two rollers, thus closing grooves 68h in that area. In this way rollers 68 and 68:: roll excess water from the entire area of the films before they enter the drying chamber while permitting the hooks 55 to pass between them.

As the rod 5i? and the books 55 pass over the left hand sprockets 32 the film now hangs directly below the books 55, since the axles of the sprockets 32 do not extend all of the way across the dryer chamber. The hooks 55-carry the film around the sprockets 33 and back up around the next set of sprockets 32 in the top of the drying chamber. In this manner therod 5G and its hooks 55 convey the film through the drying chamber, wherein the film always depends as noted. The filmthus hanging vertically in the drying chamber is subjected to a stream of warm air on both sides thereof which is circulated by the blowers 16 as described above so that the film is dried. It has been found that using this type of drying arrangement, the time necessary completely to dry at film can be reduced to as low as three minutes.

As the dried film next descends from the right hand sprockets 32 at the end of the drying chamber the lower edge thereof contacts one of a pair of bafl'les 69 and is guided thereby intothe bite of the rollers 40 and 41 illustrated in detail in Fig. 6. A baflle 47 is provided in the top of the drying chamber to direct part of the air stream against the film leaving the dryer, thus ensuring that the lower edge of the film contacts the bafile 69 and does not re-enter the dryer.

Referring specifically to Fig. 6, the roller 41 is made of a relatively hard substance and the roller 40 is made of a resiliently deformable material, such as neoprene rubber. The roller 49 is mounted in journals 70 secured to support members 71 of the frame of the machine. The axle 42 of the roller 41 islmounted in journals 72 also secured to the support members 71. The journals .70.

. the drying chamber.

.and 72 are so :formed and positioned that the axis of roller 41'lies above the axis of roller 40 and the distance between such axes is less than the sum of. their radii. These two features combine to'direct the film as-it-leaves the rollers in the direction of the arrow 73. As noted prevrously, sprockets 43 are rotatably mounted on axle 42 and these ensure that the chains properly position rod 50 and hooks 55 axially with respect to therollers "40 and 41, so that the hooks 55 will enter slots 74 provided therein. The sprockets 43 also ensure that the rod 56 is delivered it will pass between the rollers 40 and 41.

The sprockets 36 below such rollersserve three functions, namely, they ensure that the chainswill enga'ge with the teeth on the sprockets 43, and since they are rigidly mounted together, they ensure that the two chains will advance equally as they move in the area of the rollers. This is desirable since the two chains are not geared together at'any pointbetween the sprockets 36 and the sprockets 23 at the top left of the tank 8. Furthermore, the sprockets 36 are adjustably mounted so that they can be moved horizontally to vary the tension of the chains.

The axle d2 of the roller 40 is driven by the gear 44, as described above, by engagement with the worm gear 45 on the drive shaft 23. The diameter of; the gear 44 is smaller than the diameterof the gears 29 which drive the rollers 19, and the roller 41 is approximately the same size as the driven at a peripheral speed faster than the speed of the chains 49, which is governed by the sprockets 20. Therefore, as the film enters the bite of the it is grasped by the rolls and 25% greater than the speed of the chains so that the rolls tear even small films oil the hooks.

andmay be bent out of the way when rod 59 strikes 7 them. The film is accordingly automatically discharged.

To further ensure that the film leaves the discharge rollers at an oblique angle thereto, a plurality of wires 74 are inserted in the slots 74 in the rollers 46 and 41 and extend between them as illustrated in Fig. 6. The 7 upper ends of the Wires 74' are welded to the wall of When the passes through the rollers the wires 74' guide it onto the bafile 77. When the hook rods 50 pass through the rollers they press the wires out of their way until they have passed below the rollers. i r

A bafile 79 etxends down into tank the machine and prevents the passage of light from right to left as illustrated in Fig. l.- It should be noted at this point that the developing machine is designed to be in- 4 from the top of stalled in a wall of a darkroom so that the portion of the a 7 machine to the left ofthe baflie 79 is in darkness.

A platform 8h above the tank holds thereon a plurality of reservoirs $1. A tube, not'illustrated, extends from the bottom of each of the reservoirs to one of the tanks and each reservoir is filled with a replenishing solution I corresponding to that in the tank with which it is connected. Mounted in each tank is one of the valves illustrated in Figs. 7 and 8 to govern the flow into'the same from the associated reservoir. Such valve comprises a base member 82 secured to the wall of the tank and a top horizontal ported flange 83 adapted to receive a tube 84 which is connected to the. tube extending'from the to the circumference of the rollers so that sprockets 26. Thus, the roller 41 is rolls 4% and ll; a pulled away from the hooks if US. The peripheral speed of the'rolls is preferably about L i To facilitate this stripping, the inner edges of the vertices 67 of the hooks i1'eservoir 81. A flexible tube 85 having a. preformed -constriction 86 centrally thereof is connected to thelower .end of the tube 84, andadjacent the constriction there is rod.87 has a portion extending upwardly from the portion .-38.and,carrying on its upper end a float 89 preferably formed of a cellular plastic'material not subject to corrosion bythe developing chemicals. .The level 'ofthe liquid in the tankraises'and lowers the'iloat S9 to determine -.the;pressure of the rod 88 on the constriction 86 and in .thismanner the valve controls the level of the liquid within the tank.

- .Q As the machine is operated it is unnecessary to drain" ;a'nd replenish-the solutions in the tanks since sumcient :chemicals are carried out of the tanks on the'films which are developed so that new active chemicals "can be continually added without draining the tanks. When it is necessary periodically to clean the solution tanks, a suitable brush may be attached to one of the hook rods 50 and dragged through the tanks. The brush should be large enough to contact the walls of the tank so that it will scrapeany sludge oft of them, and since the curved bottoms-9 of the tanks are the same distance from the sprockets 31 as are the tank walls, the brush cleans the bottom of the tanks. The sludge bearing solutions are then removed from the tanks by any suitable pump or by drains in the tank bottoms.

Figs. 9 .and illustrate a wiper assembly which can be used in place of the rollers 68 and 68a in'Fig. 1 which preliminarily dries the film before it enters the drying ychamber. This assembly comprises two sets of rubber blades designated generally as 93 and 94 each heldbet tween a pair of metal plates 95, the elements being bolted together by means of bolts 96. Each of the blades of the set 93 has its end abutting against the side face of the corresponding blade of the 'set 94 and its underside is contacted by the end of the blade in the latter set just below the one that correspondsto it. Thus, as a film is dragged upwardly between the two sets of wiper or squeegee blades, the lower corner of the end of one va boss on the member 82 healing against one side of the tube. A rod 87 is pivotally mounted in the side of the member 82 below the constriction andhas a horizontal portion 88 thereof adapted to bear against the same. The

. from the'machine with the film;

blade presses against the film directly opposite a flat surface of a blade of the other set. Each of the blades of the set 93 is provided with a plurality of t'ear shaped .apertures 97 so positioned as to permit hooks 55'on the rods to pass therethrough without damage. The hooks edge of the blade and pass through a slit 98 which connects the aperture with the edge of the blade. As illustrated, the'slits 98 of the three

different blades

99, 100 and 101 of the set 93 are slightly staggered so that the corresponding slits 98 of the three blades do not all scrape across the film in the same line. 'This staggering of the slits 98 makes the scraper clean the film much moreeifectively. 7 7

It should be noted that the use of the hooks on the rod 50 has several distinct advantages. The use of detachable film hangers is completely eliminated with the result that foolproof automatic loading of the films is possible in my machine. The fact that the hook rods are permanently fixed in' the machine removes the primary enter the wide portion of such apertures remote from the cause of machine breakdown. Furthermore, the rods are rotatable with respect to the chain 46 so that the film is not bent substantially in the neighborhood of the hooks 55. For this reason the hooks can impale the-film closer to its edge without tearing it. This also prevents the film from working'loose from the hooks and falling off in the conveyor.

The use of the loading apparatus illustrated in Fig. 3 has many advantages over loadersused in the-prior art. 'The action of the hooks when they puncture the film is positively governed by the cam 58, not dependent merely upon the pull of gravity on the "hooks or r v 8 any other factor, the film being backed by theroller 39 so that the puncture is firm and definite. The new device is also adjustable for puncture of the film at any desired distance from its edge. The unique discharge apparatus of my invention illustrated in Fig. 6 also has many advantages. By rap idly tearing the film off the hooks it permits the machine Other modes of applying the principle of the invention may be employed, change being made as regards the details described; provided the features stated in any of the following claims, or the equivalent of such,

be employed.

I therefore particularly point out and distinctly claim as my invention:

1. In a photographic developing machine including a plurality of solution tanks, a pair of endless conveyor nier'nbersarranged to extend in laterally; spaced parallel relation through ,such tanks, means for driving said endless" members in synchronism, a cross-member rotatably connected between said endless members for movement 'ther'ewith', a plurality of rebent elements having sharp free ends secured to said cross-member and projecting laterally therefrom to impale a film to be processed, and means at the feed area of the machine for restraining said cross-member against free rotation in its passage through such area, thereby to stabilize and temporarily to support said'projecting elements for impaling the film.

2. In a photographic developing machine including a plurality of solution tanks, a pair of endless conveyor members arranged to extend in laterally spaced parallel relation through such tanks, means for driving said endless members in synchronism, a cross-member rotatably connected between said endlessmembers for movement therewith, a plurality of rebent elements having sharp free ends secured to gsaid cross-menibehandprojecting laterally therefrom to impale a film to be processed,

thereby 'to secure the filmfor transport with the cross member throughthe solution tanks, and means at the discharge end of the machine operative automatically to* grasp and tear the film, from said projecting elements penetrating the same. j i

3. In a photographic developing machine including a plurality of solution tanks, a pair of endless conveyor members arranged to extend in laterally spaced parallel relation throughsuch tanks, means for driving said endless members in synchronism, a, cross-member rotatably connected between said endless members for movement therewith, a plurality of sharpened ,rebentelements projecting from said'cross-member adapted to impale a filmto be processed, means at the feed area of the machine 'for restraining said cross-member against free rotation in its passage through such area, thereby to stabilize and temporarily to support the hooks for impaling the film, and means at the discharge end of the machine operative automatically to grasp and tear the film from said hooks.

4. Apparatus for conveying sheet material comprising in combination 'a pair ofendlesschains parallel to each other,means for synchronously moving said chains along their lengths, a rod rotatably connected between saidchains for movement with the same, a plurality of rebent hooks fixedon saidXiod, arollertangent to the path of said rod and having a plurality of axially spaced. slots therein positioned to pass said hooks, means for supporting a sheet of the material to be conveyed. adjacent to said roller at the side thereof from which said rod approaches said roller, and a cam positioned adjacent said roller to contact the closed sides of said hooks and force them into said slots to penetrate the thus supported sheet, the penetration of the hooks in the slots being sufiicient to cause the sheet to be moved to the vertices of the hooks. V

In an apparatus for conveying sheet material by means of two moving endless chains carrying a rotatable so that the sheet material delivered from said rollers moves at an oblique angle to the vertical plane through rod therebetween, the improvement comprising means for attaching a sheet of material to said rod comprising a plurality of parallel rebent hooks on said rod, a slotted roller parallel to said rod and adjacent to the path of said rod, said slots positioned to receive said hooks, a pair of substantially horizontal plates mounted adjacent to the side of said roller from which said rod approaches said roller and extending to a point closely adjacent to the path of said rod, said plates containing slots therethrough corresponding to the slots in said roller, a stop for the film provided on the plate remote from said roller on its end closest to the path of said rod and extending toward said roller, and a cam on the side of the path of said rod remote from said roller positioned to contact the closed sides of said hooks forcing them through the slots in said plates and into the slots in said roller as said rod moves past said roller.

6. In an apparatus for conveying sheet material, two moving endless members carrying a rock shaft therebetween, a sharpened projection on said shaft on which the sheet is impaled, a pair of rollers positioned to intercept and grasp the sheet,- and means for driving said rollers at a peripheral speed different from the linear speed of said shaft such that when said sheet enters said rollers, it is pulled off said sharpened projection.

7. In an apparatus for conveying sheet material, two moving endless members carrying a freely rotatable rod therebetween, a sharpened projection on said rod on which said sheet is impaled, a pair of rollers slotted to pass said projection and positioned to intercept and grasp the sheet of material carried by said rod as said sheet precedes said rod into said rollers, and means for driving said rollers at a peripheral speed greater than the linear speed of said endless members, whereby the sheet is torn from the rod.

8. In an apparatus for conveying sheet material, two moving endless members carrying a freely rotatable rod therebetween, a sharpened projection on said rod on which said sheet is impaled, a pair of rollers, one roller formed of a relatively hard material and the other formedof a resiliently deformable material, means for mounting said rollers in the path of movement of said rod so that the distance between their axes is less than the sum of their radii and the'plane from the axis of said resiliently deformable roller through the axis of the other makes an obtuse angle with the path the rod follows after passing through the two rollers, and means for driving said rollers at a peripheral speed different from the linear speed of said rod such that when said sheet enters said rolls, it is pulled off said sharpened projection.

9. In an apparatus for conveying sheet material by means of two moving chains carrying a rod therebetween wherein the sheet material is attached to said rod by a plurality of hooks on said rod impaling said sheet, the improvement comprising a pair of rollers slotted to receive said hooks and positioned in the path of said rods where said rods move downwardly preceded by said sheet, one of said rollers being formed of a relatively hard material and the other being formed of a resiliently deformable material, means for mounting said rollers so that the axis of the hard roller is above the axis of the resilient roller and the distance between said axes is substantially less than the sum of the radii of said rollers said rollers, a pair of. bafiies arranged to guide the sheets suspended from said books into the bite of said rollers, and means for driving said rollers at a. peripheral speed greater than the linear speed of said chains so that. said sheet is torn off said hooks. h V p I 10. In an apparatus for conveying sheet material from a first area to a second area comprising two moving endless members carrying a rock shaft therebetween, which passes through said areas, the improvement comprising ahook on said shaft, a slotted member in said first area adjacent the path of said shaft with its slot positioned to pass said hook, means for supporting a sheet of material to be conveyed on said member in a position obscuring said slot, a cam positioned adjacent the path of said shaft to force the-point of said hook into said slot to penetrate the sheet, a pair of rollers in said second area positioned to intercept and grasp the sheet, and means for driving said rollers at a peripheral speed difierent from the linear speed of said shaft such that when said sheet enters said rollers, it is pulled off said hook. e

11. In an apparatus for conveying sheet material from a first area to a second areacomprising two moving endless chains carrying a freely rotatable rod therebetween which passes through said areas, the improvement comprising a plurality of books fixed on said rod, a roller in said first area tangent to the path of said rod and having a plurality of axially spaced slots therein positioned to pass said hooks, means for supporting a sheet of material to be conveyed adjacent to said roller at the side thereof from which said rod approaches said roller, a cam positioned adjacent said roller to contact the closed sides of said hooks and force them into said slots to penetrate thesheet, a pair of rollers in said second area slotted to pass said hooks and positioned to intercept and grasp the sheet of material carried by said rod as said sheet precedes said rod into said rollers, and means for driving said rollers at a peripheral speed greater than the linear speed of said chains, whereby the sheet is torn from the rod.

12. In a photographic processing machine including developer and dryer sections, two endless members extending through said developer and dryer sections and carrying a freely rotatable rod therebetween, means for driving said members along their lengths, a rebent projection having a sharp free end on said rod on which a sheet of material to be processed is impaled, said endless members extending through said dryer section in a generally sinusoidal path having a horizontal axis, with said projection remaining substantially vertical in movement along such path as the result of the rotatable support of the rod by the endless members, and means for forcing a stream of hot air through said dryer section from the top to the bottom thereof.

13. In a photographic processing machineincluding developer and dryer sections, two endless chains extending through said sections and carrying a freely rotatable rod therebetween, means for driving said chains along their lengths, a rebent hook on said rod, means at a point in the path of said rodbefore it enters said developer section for impaling a sheet of material to be processed on said hook, means at a point in the path of said rod as it leaves said dryer section for tearing said sheet off said hook, said chains extending through said dryer section in a generally sinusoidal path having a horizontal axis, with the hook maintained in substantially dependent relation in movement along such path asthe result of the rotatable support of the rod by the chains, and means for forcing a stream of hot air through said dryer section from the top to the bottom thereof.

'14. The machine of claim 12 characterized further by the inclusion of two contacting sets of resiliently de-" 1'1' formable blades one set mounted on each side of the path of said rod at a point between said developer. and dryer sections, the end of each blade in one set contacting the under side of a blade in the other set, and a slot in the edge of each blade in one setpositioned t0 passsaid projection said slots lying in difierent lines which ,are parallel to the path of said rod.

' 15. In an apparatus for conveying sheet material/two moving endless members carrying a freely rotatable rod therebetween, a sharpened projection on said rod on which said sheet is impaled, a pair "of rollers slotted to pass said projection'and positioned to interceptand grasp the sheet of material carried bytsaid rod as said sheet precedes said rod into said rollersymeans for dri'ving said rollers at a peripheral speed greater than the linear speed of saidendless members, whereby the sheet is torn from the rod, and a resilient wire in the slot in References Cited in the file of this patent UNITED STATES PATENTS 1,472,902 Bulkeley Nov. 6, 1923 1,553,920 Smothers Sept. 15, 1925 1,679,411 De Potters Aug. 7, 1928 1,679,412 De Potter Aug. 7, 1928 1,683,883 Greene Sept, 11, 1928 1,709,788 Greene Apr. 16, 1929 1,796,366 Greene et a1. Mar. 17, 1931 1,877,659 Greene Sept. 13, 1932 2,348,355 Miller May 9, 1944 FOREIGN PATENTS a 265,221 Switzerland July 17, 1950