Photo-processing apparatus

Abstract: A photo-processing apparatus equipped with a stock tank section (7) which contains and stores a strip-shaped photo-sensitive material between a pair of guide plates (21,22) provided so as to sandwich the transversal direction of the photo-sensitive material; wherein the apparatus includes a tank width changing mechanism which changes a distance between the pair of guide plates (21,22) depending on the width of the photo-sensitive material to be passed through the stock tank section (7). The paper to be contained and stored in the stock tank section (7) does not twist and is smoothly pulled out from the exit section by a method wherein the distance between one pair of guide plates restricting the movement of the paper in the transversal direction is adjusted depending on the width of the paper to be passed through the stock tank section (7).

Description: The present invention relates to a photo-processing apparatus, and more particularly to a photo-processing apparatus in which the movement in the transversal direction of the photo-sensitive material (hereinafter called as paper) is restricted in a stock tank section so that the paper will not be twisted. Fig. 1 shows one example of the configuration of a photo-processing apparatus. This photo-processing apparatus consists of a printer section 1 for printing papers and a processor section 2 for performing a process on the printed paper such as developing. The printer section 1 is further provided with a loading section 3 for transferring the paper to an exposure stand along a transfer path for the paper, an exposure stand 4 for exposing the paper to light to print it, an advance section 5 for accurately transferring the paper with a certain length, a paper transfer section 6, a stock tank section 7 where a loop is formed to hold the paper so as to adjust the advancing speed of the paper to be sent to the processor section 2, and an exit section 8. Moreover, a processor rack section 9 is provided in the processing tank of the processor section 2 for conducting the coloring and developing, bleaching, and fixing and stabilizing, a dryer section 10 is provided in the drying tank for drying the paper, and a cutter section 11 is provided near the exit, respectively. The strip-shaped paper contained in the paper magazine (not shown) in the form of a roll is pulled out and transferred by a transfer roller, and sent to the processor section 2 through the loading section 3, exposure stand 4, advance section 5 and paper transfer section 6. The stock tank section 7 is provided to adjust the advancing speed of the paper to be sent to the processor section 2, and is so designed that it is possible to contain the paper with a certain length in the stock tank section 7 with limited space by a method wherein a small loop is naturally formed in multi-fold laps as shown in Fig. 5. Recently, the number of kinds of paper width that can be processed with a photo-processing apparatus has, however, increased so that the difference between the maximum width and minimum width has increased. If the size of the tank section in the transversal direction is determined in accordance with the maximum width, the minimum size paper will not be restricted in the transversal direction so that the loop is disordered as shown in Fig. 6. In worst cases, there is a problem that the paper cannot be pulled out from the stock tank section because of twist. EP-A-0 652 468 describes a mechanism for changing a guide width depending on the width of a photo-sensitive paper in a photo-processing apparatus. The mechanism is provided with a pair of guide members, a pair of screw shafts connecting the guide members and a pulse motor rotating the screw shafts through a belt to enlarge or reduce the distance between the guide members. No unthreaded supporting shaft of the guide members is used. EP-A-0 519 867 discloses a stock tank for strip material, like exposed photo papers. The stock tank is provided with a pair of guide plates and a tank width changing mechanism which changes the distance between the guide plates. The changing of the tank width is effected by using screw shafts cooperating with the guide plates. Also this prior art is silent on unthreaded supporting shafts of the stock tank. GB-A-2 169 267 refers to an apparatus through which a strip, like a photographic film or print paper, is arranged to be passed. The apparatus is provided with guide members for said strip, which are relatively moveable by a separation adjusting mechanism which changes the distance between the guide members. The rotating part of the separation adjusting mechanism is a screw shaft having one or more bevel gears. There is no mention of a rotatable supporting shaft of the guide members. It is an object of the present invention to improve a photo-processing apparatus having a stock tank section with guide plates for a photo-sensitive material, like photo paper, in such a way that when changing the distance between said guide plates the sliding of the guide plates is smoothened. This object is met by a photo-processing apparatus a defined in claim 1. According to a preferred embodiment of the photo-processing apparatus of this invention, said apparatus is provided with a sensor for detecting the width of the photo-sensitive material to be passed through the stock tank. According to another preferred embodiment of the photo-processing apparatus of this invention, said apparatus is provided with a sensor for detecting the presence of the photo-sensitive material in the stock tank. Fig. 1 is an explanatory view of an embodiment of a photo-processing apparatus of the present invention; Fig. 2 is an explanatory view of a stock tank section in the photo-processing apparatus of the present invention; Fig. 3 illustrates a state of the paper to be contained in the stock tank section in Fig. 2; Fig. 4 illustrates a state of the paper in the case where the width of the stock tank section in Fig. 2 is not changed; Fig. 5 illustrates a state of the paper which is contained in a stock tank section of the conventional photo-processing apparatus; and Fig. 6 illustrates a state of the paper which is contained in the stock tank section of the conventional photo-processing apparatus. Next, the photo-processing apparatus of the present invention is described with reference to the attached drawings. Fig. 1 illustrates an embodiment of a photo-processing apparatus of the present invention, Fig. 2 illustrates the stock tank section in the photo-processing apparatus of the present invention, Fig. 3 illustrates a state of the paper contained in the stock tank section in Fig. 2, and Fig. 4 illustrates a state of the paper in the case where the width of the stock tank section in Fig. 2 is not changed. As a configuration of the photo-processing apparatus of the present invention, it is possible to use a conventional one. The configuration of an embodiment of the photo-processing apparatus of the present invention shown in Fig. 1 is the same as that described above. The difference of the present invention from the prior art described above is that a tank width changing mechanism for changing the width of the guide plate in the stock tank section 7 is provided in the stock tank section 7. In Fig. 2, the stock tank section in the present invention comprises a pair of guide plates 21, 22 made of iron group metal plate and the like, a supporting shaft 23 made of stainless steel, brass and the like, and a tank width changing mechanism (not shown) which moves the guide plates 21, 22 in the transversal direction of the paper P. The guide plates 21, 22 are thin plates and provided between the paper transfer section 6 and exit section 8 to be paired on the both sides of the paper and to sandwich the transversal direction of the paper. Thus, the paper fed from the paper transfer section 6 is gathered between the guide plates 21, 22 for a while, and contained and stored till it is sent to the processor section 2 from the exit section 8. Moreover, the guide plates 21, 22 have shaft insertion holes 25, 26 and are supported by a supporting shaft 23. The both ends of the supporting shaft 23 are supported by the rear panel of the printer section 1 and stock tank supporting plate of the photo-processing apparatus. As the tank width changing mechanism, it is desirable to use, for example, a mechanism wherein at least one of the supporting shaft 23a, 23b, 23c is divided into threaded right screw and left screw sections so that they rotate in reverse direction each other with an approximate center of the shaft being a border, and to make the supporting shaft insertion hole 25, 26 be a threaded hole correspondingly. By doing so, it is possible to adjust the interval L1 by automatically or manually rotating the supporting shaft so as to symmetrically move the guide plates 21, 22. In this case, the unthreaded supporting shaft simply serves as a guide for the movement of the guide plate. Moreover, if the supporting shaft is automatically rotated, it is possible to provide a pulley on the supporting shaft to link it to a driving motor by means of a timing belt or to employ a toothed mechanism which is linked to the driving motor. Moreover, it is possible to employ a tank width changing mechanism in which a rack is provided to each of the guide plates 21, 22 to face to each other with a pionion being intervened between the tooth of each rack. In this case, the guide plates 21, 22 symmetrically move when the pinion is rotated. It is possible to provide a sensor on the end section of any rack so as to detect the width of the tank. Moreover, it is also possible to provide a sensor for detecting the width of the paper to be passed through the stock tank section, and a sensor for detecting the presence of the paper in the stock tank section as required so as to automatically control the driving motor. Furthermore, in the above-mentioned tank width changing mechanism, it is also possible to provide a supporting shaft rotation mechanism on a supporting shaft other than the threaded shaft. The supporting shaft rotation mechanism is provided to smoothen the movement of the guide plate 21, 22 by rotating the supporting shaft before the guide plates 21, 22 start to slide so as to change static friction to dynamic friction. In the case of the tank width changing mechanism employing the threaded shaft, for example, the center supporting shaft 23b is threaded, and a rotation mechanism is connected to the other supporting shafts 23a, 23c. An automatic or manual rotation mechanism is applicable as in the case of the tank width changing mechanism. If the rotation mechanism is connected to a driving motor via a pulley, it is necessary to adjust the rotation mechanism to start before the tank width changing mechanism starts. However, it is possible to terminate the driving at the same time. Moreover, if a tank width changing mechanism is added without threading the supporting shafts, it is desirable to provide a supporting mechanism on each supporting shafts 23a, 23b, and 23c. In the apparatus with a supporting shaft rotation mechanism as described above, the accuracy of the amount of movement of the guide plates 21, 22 is improved in comparison to the mechanism with the supporting shaft which does not rotate. Namely, in the non-rotatable supporting shaft, sticking dust makes the movement of the guide plate heavier, thereby requiring larger torque or making it difficult to move the guide plate. Furthermore, the guide plate might be caught by the supporting shaft, resulting in irregularity of guiding width or inclined guide plate, thereby causing troubles of zigzagging or clogging the paper transfer. However, rotation of the supporting shaft reduces the friction between the width guide and supporting shaft and smoothens the sliding. In the case of threaded type, particularly, the load on the feed screws is reduced, which reduces driving torque. Next, the function of the photo-processing apparatus in the present invention is explained based on Figs. 3 and 4. As shown in Fig. 3, if the distance between the guide plates 21, 22 is adjusted to a degree slightly larger than the width of the paper P to be contained and stored between them, small loops are regularly formed from the bottom. The loops wait until the processor section 2 is ready for processing, and are sent from the exit section 8 without being twisted. However, if the paper P with a width less than L2 is passed through between the plates without adjusting the distance L2 between the guide plates 21, 22 as shown in Fig. 4, the paper P is contained with being distorted. Accordingly, not only extra force to pull out the paper is required but also a fear of clogging the exit section 8 with twisted paper is generated. As described above, the photo-processing apparatus of the present invention has a tank width changing mechanism in the stock tank section so that the paper to be contained and stored in the stock tank section does not twist and is smoothly pulled out from the exit section by a method wherein the distance between one pair of guide plates restricting the movement of the paper in the transversal direction is adjusted depending on the width of the paper to be passed through the stock tank section. Furthermore, provision of a supporting shaft rotation mechanism reduces the friction between the supporting shaft and the guide plates to smoothen the sliding of the guide plates so that the moving amount of the guide plates is accurately controlled, without irregular guiding width and, thus, without trouble in paper transfer.

Claims: A photo-processing apparatus comprising a stock tank (7) to contain and store a strip-shaped photo-sensitive material between a pair of guide plates (21,22) which sandwich the photo-sensitive material in the transversal direction thereof, wherein the stock tank is provided with a tank width changing mechanism comprising at least one threaded shaft, by which the distance between the two guide plates may be changed in dependence on the width of the photo-sensitive material to be passed through the stock tank, characterized in that : the pair of guide plates is supported by at least one unthreaded supporting shaft, in that the stock tank (7) is further provided with a supporting shaft rotation mechanism by which the at least one unthreaded supporting shaft (23a, 23b, 23c) of the guide plates (21, 22), which is distinguished from said at least one threaded shaft of the tank width changing mechanism, is started to rotate before the tank width changing mechanism starts to operate. The photo-processing apparatus according to claim 1, characterized in that it is provided with a sensor for detecting the width of the photo-sensitive material (P) to be passed through the stock tank (7). The photo-processing apparatus according to claim 1 or 2, characterized in that it is provided with a sensor for detecting the presence of the photo-sensitive material (P) in the stock tank (7).

Inventors: NARUKAMI SHINJI, NARUKAMI, SHINJI, Narukami, Shinji, c/o Noritsu Koki Co. Ltd.
Applicants: NORITSU KOKI CO LTD, NORITSU KOKI CO., LTD.
Application year: 1995
Main classification: G03D13
IPC codes: G03B27, G03D3, G03D13, B65H23