Process tank having an adjustable processing path length and method of adjusting the same

A processing assembly includes a processing tank having a processing path through which a photosensitive material to be processed travels. The tank includes a processing path length adjusting mechanism which forms a part of the processing path and is capable of adjusting a length of the processing path between at least a first predetermined length and a second predetermined length which is different than the first predetermined length. This provides for a versatile processing tank that is adjustable between a normal processing path length for normal photoprocessing and a shorter processing path length for processing applications in which a shorter processing path length is sufficient.

DETAILED DESCRIPTION OF THE INVENTION 
Referring now to the drawings, wherein like reference numerals designate 
identical or corresponding parts throughout the several views, FIG. 1A 
shows a processing tank 9 having a processing path length adjusting 
mechanism 11. Processing tank 9 can be for any of the processing steps of 
a processor as previously discussed. As illustrated in FIG. 1A, processing 
tank 9 can be of a rack and tank arrangement as described in, for example, 
U.S. Pat. No. 5,311,235, the subject matter of which is herein 
incorporated by reference. It is further noted that path length adjusting 
mechanism 11 can also be applied to a variety of other types of processing 
tanks. 
In the rack and tank type arrangement, a rack 15 can be easily inserted and 
removed from a tank 17, to form a low volume photosensitive material 
processing vessel. 
When rack 15 is inserted in tank 17, a space 19 which defines a processing 
path 21 for the passage of photosensitive material is formed. Processing 
path 21 includes a downward portion 21', a turnaround portion 21" and an 
upward portion 21'". Rack 15 includes a plurality of rollers 23a-23d as 
illustrated in the figure, while tank 17 includes nozzle openings 25a-25g 
and 25a'-25g' which supply processing solution to tank 17. The number of 
drive rollers and nozzle openings are illustrated as an example, and it 
recognized that the number of drive rollers and nozzles used are based on 
design considerations. 
As illustrated in FIG. 1A, in addition to drive rollers 23a-23d rack 15 
includes processing path length adjusting mechanism 11 which is 
operationally connected to and provided adjacent to lowermost drive roller 
23a so as to define a space 21a. Space 21a forms a part of the processing 
path 21 therebetween which is turnaround portion 21". As shown in FIG. 1A, 
an upper surface 11a of processing path length adjustment mechanism 11 is 
curved to match the curvature of lowermost drive roller 23a to form the 
path of turnaround portion 21". 
Tank 17 with rack 15 inserted therein includes an entrance 25 where the 
photosensitive material enters tank 17 and is conveyed by the drive 
rollers 23a-23d along downward portion 21' of path 21. While the 
photosensitive material is being conveyed, processing solution is supplied 
to the photosensitive material by way of nozzle openings 25a-25g and 
25a'-25g'. As the photosensitive material is conveyed to the lowermost 
drive roller 23a, it is transported along turnaround portion 21" between 
lowermost drive roller 23a and upper surface 11a of processing path length 
adjusting mechanism 11 to the upward portion 21'" of processing path 21, 
and finally to an exit 27. 
The position of processing path length adjusting mechanism 11 illustrated 
in FIG. 1A forms a normal processing path length. If a photoprocessing 
operation in which a shortened processing path length is sufficient, then 
processing path length adjusting mechanism 11 can be moved or expanded to 
the position shown in FIG. 2A. As illustrated in the embodiment of FIGS. 
1A and 2A, processing path length adjusting mechanism 11 can be a flexible 
member or bellows which is moved or expanded so as to block at least the 
lower nozzle openings 25f, 25g, 25f, 25g' and move turnaround portion 21" 
upward. This provides for a shortened processing path length as 
illustrated in FIG. 2A. With the shortened processing path length, during 
processing, the photosensitive material enters and exits processing tank 
17 in the same manner as described with reference to FIG. 1A, however, 
since the path length adjusting mechanism 11 has been moved or expanded, 
the processing path length is shortened. 
FIG. 2A illustrates the positioning of path length adjusting mechanism 11 
to one point in which the lower nozzle openings 25f, 25g, 25f, 25g' are 
blocked. It is recognized that processing path length adjusting mechanism 
11 can be moved or expanded to a plurality of positions depending on the 
length of the desired processing path. For example, it is recognized that 
processing path length adjusting mechanism 11 could be moved or expanded 
upwardly so as to block further nozzle openings and provide for an even 
shorter processing path length. It is further recognized that processing 
path length adjusting mechanism 11 can be moved or expanded an amount 
which is less than what is illustrated in FIG. 2A so as to keep the lower 
nozzle openings open but at the same time provide for a shorter processing 
path length. 
As illustrated in FIGS. 1A-1B and 2A-2B, there is a spacing between drive 
rollers 23a and 23b to facilitate the movement or expansion of path length 
adjusting mechanism 11. In order to insure a uniform processing path 21 
and at the same time reduce the volume within tank 17, the present 
invention can include an intermediate spacer member 40 in the spacing 
between rollers 23a and 23b. Intermediate spacer member 40 is illustrated 
in detail in FIGS. 3 and 4 and comprises a first member 40a having a 
plurality of spaced teeth-like members 41 and a second member 40b having a 
plurality of spaced teeth-like members 43. 
The operation with respect to an embodiment of the invention will now be 
described. As illustrated in the FIGS. 1A and 2A, path length adjusting 
mechanism 11 can be in the form of an expandable flexible member or 
bellows. Path length adjusting mechanism 11 can be operationally connected 
to the lowermost drive roller 23a, such that a movement or expansion of 
path length adjusting mechanism 11 from the position illustrated in FIG. 
1A to the position illustrated in FIG. 2A will cause a corresponding 
movement of drive roller 23a; while maintaining spacing 21a between drive 
roller 23a and surface 11a of path length adjusting mechanism 11 which 
defines turnaround portion 21". 
One example for actuating or causing the movement or expansion of path 
length adjusting mechanism 11 will now be described. FIG. 1B illustrates 
the position of path length adjusting mechanism 11 which corresponds to 
the position illustrated in FIG. 1A. As noted in FIGS. 1A, 1B and 5, the 
apparatus of the present invention can include a gearing arrangement which 
comprises at least one screw or worm gear 31 positioned at a side of tank 
17. As illustrated in FIGS. 1B and 2B, screw gear 31 can be inserted next 
to a drive gear arrangement 100 which is utilized to drive rollers 
23a-23d. As shown in FIG. 5, screw gear 31 can engage with a rack gear 33 
having a hole 33'. A shaft 33a onto which the roller 23a is mounted 
extends through hole 33' of rack gear 33. 
Screw gear 31 includes an extension part 37 which extends above rack 15 and 
ends in a handle 15a. The rack gear 33 is operationally associated with 
the shaft of the drive roller 23a, path length adjusting mechanism 11 and 
first member 40a such that a turning of handle 15a will cause a rotation 
of screw gear 31 engaged with rack gear 33 so as to move drive roller 33a 
and correspondingly move first member 40a and path length adjusting 
mechanism 11 to the position illustrated in FIGS. 2A and 2B and vice 
versa. It is recognized that alternative arrangements such as a pneumatic 
assembly or a different type of gear arrangement can be used instead of 
the disclosed screw and rack gear to achieve the described movement. 
During the movement or expansion of path length adjusting mechanism 11, 
each of teeth-like members 41 and 43 are insertable into corresponding 
spaces 45 created by the teeth-like members 41 and 43 of each of the first 
and second members 40a and 40b. In the position illustrated in FIGS. 1A 
and 1B, teeth-like members 41 and 43 are not deeply inserted into spaces 
45. When path length adjusting mechanism 11, first member 40a and drive 
roller 23a are moved to the position illustrated in FIGS. 2A and 2B, the 
bellows are expanded and the teeth-like members 41,43 are inserted into 
corresponding spaces 45. As described above, intermediate spacing member 
40 maintains the proper spacing for processing path 21 and at the same 
time, minimizes the internal volume of tank 17 so as to require less 
processing solution. As a further feature of the present invention, it is 
noted that the use of a bellows for processing path length adjusting 
mechanism 11 also minimizes the internal volume of the tank 17. It is 
recognized that intermediate spacing member 40 is not limited to the 
disclosed configuration. It is noted that a collapsible flexible member 
which collapses upon the upward movement of path length adjusting member 
11 can be used as an intermediate spacing member. 
As illustrated in FIGS. 1A-1B and 2A-2B, processing path length adjusting 
mechanism 11 is shown as an expandable bellows. This is only one example 
and it is recognized that any movable, flexible or expandable member can 
be utilized as processing path length adjusting mechanism 11. For example, 
as one example, a piston and cylinder arrangement can be provided such 
that the piston is operationally connected to roller 23a and intermediate 
spacer member 40 and includes a curvature to define turnaround portion 
21". Movement of the piston can be achieved in a known manner by using a 
pneumatic cylinder which can be, for example, mounted on the tank. 
FIGS. 6A and 6B are perspective drawings of textured fluid-bearing surfaces 
200 and 205 which can be located on one or both surfaces of processing 
path 21. Textured surfaces 200 and 205 are textured by any known process, 
e.g., knurling, molded, EDM electro-discharged machined or applied. Knurls 
202 or 206 are respectively shown on surfaces 200 and 205. The texturing 
(FIGS. 6A,6B) and cantering (FIG. 6A) improve the flow of processing 
solution between the photosensitive material and the one or both surfaces 
of processing path 21, and prevent the photosensitive material from 
sticking on the surfaces. 
The present invention can further include a control mechanism 50 to 
automatically actuate processing path length adjusting mechanism 11. For 
example, control mechanism 50 can include a computer or a central 
processing unit which is operationally connected to screw drive gear 31 by 
way of line 53. A plurality of desired predetermined lengths of the 
processing path can be inputted into the control mechanism 50. Therefore, 
if the user knows of the specific type of processing to be performed, he 
could input the desired processing path length into control mechanism 50 
which is used for that particular type of photoprocessing. Control 
mechanism 50 can automatically actuate screw drive gear 31 to move path 
length adjusting mechanism 11 to the designated position along tank 17 so 
as to provide for the particular predetermined length of the processing 
path. 
The invention has been described in detail with particular reference to 
certain preferred embodiments thereof, but it will be understood that 
variations and modifications can be effected within the spirit and scope 
of the invention.