Operating device for developers of photographic material

Abstract

 Operating device to rotate the film supports (13,14) for a developer of photographic material, which comprises a plurality of tanks (5,6) containing the liquid chemical agents and which are provided with a circuit having a pump (7) for the reagent circulation.
According to the invention, the device comprised a relative rotor (15) associated with the supports (13,14) and a nozzle (16), disposed in front of the rotor (15) and installed at the end portion of the return pipe (9) of the circulation circuit of the reagents, which pipe is connected to the tank.
In this manner, the fluid jet of the reagents coming from the nozzle (16) and regulated by a valve (17) may rotate the supports (13,14) and also the photographic material without use of the conventional mechanical devices for driving said supports (13,14).

Description

[0001] The invention concerns the developers of photographic materials like conventional films and disc film and particularly refers to the operating device for rota tion of the supports of the said material into the tanks of these developers, which contain the different chemical baths, and into the last drying chamber. As already known, developers are provided which substantially comprise a plurality of tanks into which the specific supports for the photographic materials are successively disposed and transferred, which supports are generally constituted by drums on which the conventional films are wound as well as by mandrels on which the disc films are arranged.

[0002] Every tank is normally provided with a hydraulic circuit having a pump, for keeping in circulation the liquid chemical reagents.

[0003] In addition, every tank is also provided with a powered system to rotate the drums or the film holder mandrels around the relative supports. so as to ensure an uniform development of the films.

[0004] This solution is not very rational and cheaper, since every tank requires mechanical devices (generally constituted by gear trains with geared motor) which complicate the developer construction and maintenance and also involve an excessive energy consumption.

[0005] It would be-desirable, and forms the.scope of the invention, to simplify such developers and to utilize advantageously the devices which must be necessarily applied on the same developers.

[0006] This scope is obtained in a developer for the development of photographic material, which comprises a plurality of tanks containing the liquid chemical reagents and which are provided with a circuit having a pump for the reagent circulation, the rotating supports for the photographic material being insertable and transferable within the said tanks.

[0007] According to the invention, the developer is characterized in that the supports for the photographic material are associated with a rotor, which is able to be rotated by means of a flowing jet coming from a nozzle placed in front of the said rotor and installed at the end portion of the return pipe of the reagent circulation circuit, which pipe is connected to the tank.

[0008] Besides, in order to permit the rotational speed of the supports of the photographic material to be varied, the circuit for the reagent circulation in every tank comprises an adjustment valve, which is disposed downstream of the circulation pump and upstream of the jet for ope rating the said rotor.

[0009] These and other features of the invention will result apparent from the following description, by way of an exemplifying and not limiting scope, with reference to the enclosed drawing in which:

- Fig. 1 shows a schematic perspective view of a part of a developer provided with the device according to the present invention;

- Fig. 2 shows a schematic per_fective view of a further part of the developer of Fig. 1.

[0010] Two tanks 5,6 of a developer are schematically represented in Fig. 1, each of them being provided with a hydraulic circuit which comprises a pump 7 having a suction pipe 8 and a delivery pipe 9.

[0011] The liquid chemical reagents for the development of the photographic films are circulated within the tanks 5,6 and the maximum reagent level within the tanks is controlled by means of an overflow pipe 10.

[0012] In the inside of the tanks 5,6 the supports for the films are arranged. which are generally constituted by longitudinal rods 11 having end portions which are inserted into suitable seats which are provided on the edges of the tanks, so as to be easily insertable therein and extractable therefrom.

[0013] Adequate plates 12 which may be slided for their regu lation are inserted on the rods 11, on which plates a drum 13 for the conventional films or a mandrel 14 for the disc films are respectively engaged.

[0014] According to the main feature of the invention, the drum 13 and the mandrel 14 are carrying a relative ro tor 15, which is keyed at one end portion of the relevant shaft.

[0015] When the developer is loaded and the pump 7 is operating, the rotor 15 is submitted to the jet of the chemical reagents under circulation, which jet is coming out from a nozzle 15 constituting the end portion of the return pipe 9, which conveys the reagents back to the tank.

[0016] Therefore, the dynamic energy of the delivery jet of the reagents is utilized to rotate the rotor 15 and, consequently, the drum 13 or the mardrel 14.

[0017] This solution permits the pump 7 to be rationally used and eliminates the need for a special operating device for the rotation of the supports for the films.

[0018] According to an additional feature of the invention, a regulation valve 17 is inserted in the pipe 9 which delivers the reagents towards the tank, wherein this valve permits the dynamic characteristics of the jet 16 to be varied depending on the different rotational speeds which are required by the drum 13 or the mandrel 14. The valve 17 may be manually or automatically operated,

[0019] in the last case by means of optical or electronic devices of any known kind.

[0020] Furthermore, the tanks 5,6 contain some thermoctati- cally controlled heating elements for the reagents and are provided with adequate protection covers.

[0021] These components of the conventional type aren't repre sented in fig. 1.

[0022] Finally, fig. 2 schematically represents a drying tank 20, in a partially cutaway view, which tank constitutes the last element of the developer.

[0023] The tank 20 is provided with a system which is similar to that one described for the tanks 5,6 of the chemical baths.

[0024] Also in this case the film support (in the drawing the mandrel 14 for the disc films) has a rotor 15 which is operated by the jet 21 of the drying air, generated by a fan 22.

[0025] The rotor 15 is included in an envelope 23 connected to a duct 24, which extends for the whole width of the tank 20 and is provided with slits 25 for the uniform εir distribution on the films to be dried.

[0026] An electric heating element 26 for heating the air is inserted into the duct 24.

[0027] Therefore, also the drying tank 20 utilizes the principle on which the invention is based, namely that one to take advantage of the elements which are necessarily provided on the developer (pump 7 for the circula- tior of the chemical reagents, fan 22 for the circulation of the drying air) for keeping the film supports in rotation, so eliminating additional control devices for the latter.

Claims

1. Operating device for developers of photographic material, which comprise a plurality of tanks containing the liquid chemical reagent for the development and which are provided with a circuit having a pump for the reagent circulation, the rotating supports for the photographic material being insertable and transferable within the said tanks, characterized in that the supports ('13,14) for the photographic material are as sociated with a rotor (15), which is able to be rotated by means of a fluid jet coming from a nozzle (16), which is disposed in front of the said rotor and is installed at the end portion of the return pipe (9) of the circulation circuit for the reagents, which pi pe is connected to the tank.

2. Device according to claim 1, characterized in that the circuit for the reagent circulation in every tank comprises a regulation valve (17), which is disposed downstream of the circulation pump (7) and upstream of the nozzle (16) for operating the rotor (15).

3. Device according to claim 1, in which the developer comprises at least an additional tank for drying the films, which is provided with a fan and a heating element for heating the air, characterized in that the ro tor (15) is able to be rotated by means of a jet (21) of the air generated by the fan (22) and that the same rotor is included in an evelope (23) connected to a duct (24), which is provided with slits (25) for the uniform air distribution on the photographic material.

Drawing