Photographic processing apparatus
United States Patent [1 1 Ratowsky 1 Apr. 22, 1975 PI&#39;IOTOGRAPI-IIC PROCESSING APPARATUS [75] Inventor: Simon Ratowsky, Downsview,  
 Ontario, Canada [73] Assignee: Monrick Holding Limited,  
 Downsview, Ontario, Canada [22] Filed: Feb. 12, 1973 [21] App]. No.: 331,787  
 [52] US. Cl 354/335; 354/343 [51] Int. Cl. G03d 13/02 [58] Field of Search 95/93, 96, 97, 98, 100;  
 29/D1G. 47, 157.3 A, 193; 269/99, 100, 283; 248/223, 225; 211/7, 46, 94  
 [56] References Cited UNITED STATES PATENTS 3.304.850 2/1967 Gall 95/93 3.511,555 5/1970 OBrien 350/117 3.623.416 11/1971 Anderberg 95/93 3,693,529 9/1972 Stablcr 95/93 3,727,535 4/1973 Streeter 95/93 FOREIGN PATENTS OR APPLICATIONS 484.930 9/1953 Italy 95/93 565,314 7/1957 Italy 95/96 Primary E.\&#39;aminer-Fred L. Braun [57] ABSTRACT A carrier for use in processing photographic sheet material, in which a hollow cylindical drum is provided on its inner surface with spaced rods for retaining the sheets arcuately in the drum, the main body portion of each rod being each concavely curvilinear in crosssection with a shank interconnecting the body portion with the inner surface of the drum. The rods are preferably selectively insertable in slots located on the inner surface of the drum at spaced intervals around its periphery.  
 6 Claims, 4 Drawing Figures PHOTOGRAPHIC PROCESSING APPARATUS This invention relates to the processing of photographic material.  
  One type of apparatus used in processing photographic material consists of a carrier in which one or more photographic sheets is arcuately disposed inside an axially rotatable drum. Preferably longitudinal flanges are located on the inside surface of the drum to hold the sheets in arcuate position against the drum wall. To process the sheets, the drum is closed and liquid processing chemicals are introduced into the drum. The drum is then rolled with its longitudinal axis disposed horizontally.  
  By a method as disclosed in applicants US. Pat. No. 3,705,544 issued Dec. 12, 1972 the cylindrical processing drum is also oscillated about a point on its axis as the drum is rotated, to form a wave in the liquid chemical moving back and forth along the drum. Because the drum is rolling, the wave travels along a helical path and strikes the longitudinal flanges retaining the photographic sheets. This causes splashing of the liquid chemical which marks the sheets and reduces the quality of the finished product. A similar problem arises if the drum is rolled without oscillation.  
  It is an object of the present invention to provide an improved retaining device for the inside surface of a photographic processing drum which will inhibit splashing of liquid chemical when the drum is rotated.  
  An example embodiment of the invention is shown in the accompanying drawings in which:  
  FIG. 1 is an exploded perspective view showing a drum carrying a retaining rod of the invention;  
  FIG. 2 is a perspective view showing one end of the drum of FIG. I, carrying removable retaining rods;  
 FIG. 3 is an end view of the drum of FIG. 2; and  
  FIG. 4 is an enlarged end view of a segment of the drum of FIG. 3.  
  The embodiment shown in the drawings consists of a photographic sheet material carrier comprising a hollow. cylindrical drum 12 and a pair of end closure caps 14. Drum 12 has a pair of cams 16 on its outer surface for oscillating the carrier about a fulcrum on its axis when the drum is horizontally disposed and rotated.  
  Inner surface 18 of drum 12 carries a plurality of spaced retaining rods 20 longitudinally disposed parallel to the axis of the drum. Each rod 20 has a main body portion 22 substantially circular in crosssection and a parallel, radial shank 24 lying in the plane of the axis of the main body portion. Shank 24 comprises a pair of flanges 26 having outwardly diverging side walls 28 as seen in cross-section in FIG. 4.  
  Inner surface 18 of drum 12 also carries a plurality of spaced, longitudinally disposed slots 30. Each slot 30 is formed by a pair of spaced, parallel tongues 32 having inwardly converging side walls 34. Shank 24 of a rod 20 is longitudinally receivable slidably in a slot 30 as seen in FIG. 2. Preferably shank 24 fits snugly in slot 28 with side walls 28 of the shank frictionally engaging side walls 34 of the slot. End caps 14 may also serve to retain rods 20 in slots 30 by preventing their longitudinal movement when the carrier is closed.  
  Slots 18 are located at a number of different positions on the inner circumference of drum 12 for selective use to accommodate different sizes of photographic sheet material. Drum 12 also carries on its inner surface 18 a plurality of shallow ribs 36 parallel to slots 30.  
  In the operation of the device, rods 20 are inserted into slots 30 at arcuately spaced distances around the periphery of drum 12 corresponding to the lengths or widths of sheets 40 of photographic material to be processed. Sheets 40 are then inserted into drum 10 between pairs of rods 20 to lie arcuately against ribs 36, as seen in FIGS. 1 and 3. Drum 12 is then closed by end caps 14, a predetermined amount of liquid processing chemical is introduced into the drum through one of the end caps, carrier 10 is disposed horizontally, and the carrier is rotated to oscillate about a fulcrum on its axis, causing a continuous wave in the liquid chemical to move spirally back and forth along the drum. As the wave impinges on rod 20 the configuration of main body portion 22 of the rod inhibits splashing, allowing liquid to flow more smoothly over the rod.  
  It will be appreciated that the cross-sectional shape of main body portion 22 of rod 20 may be other than circular but it must be convexly curvilinear (of which a circular shape is an example) to allow the liquid chemical to flow over it.  
 I claim:  
  1. In a carrier for use in processing photographic sheet material, said carrier comprising a hollow cylindrical drum having end closing means, a plurality of spaced retaining rods longitudinally disposed in parallel relationship along the inner surface of the drum, each of said rods having a main body portion convexly curvilinear in cross-section and a shank interconnecting the main body portion with the drum surface to space the main body portion a predetermined distance from the drum surface, said rods being spaced apart around the inner surface of the drum whereby a sheet of said photographic material is receivable between a pair of said rods to lie arcuately therebetween concentrically with the inner surface of the drum.  
  2. A carrier as claimed in claim 1 in which the main body portion of the rod is circular in cross-section.  
  3. A carrier as claimed in claim 1 in which the rods are removable from the drum.  
  4. A carrier as claimed in claim 3 in which the drum has a plurality of spaced longitudinal slots disposed on the inner surface thereof, the shanks of the rods being longitudinally receivable slidably in selected slots.  
  5. A carrier as claimed in claim 4 in which the shank of each rod is outwardly diverging in cross-section and each slot is formed by a pair of spaced, parallel tongues located on the inner surface of the drum and having inwardly converging side walls.  
  6. A carrier as claimed in claim 5 in which the shank comprises a pair of diverging flanges.