FR2622708A1 - Device for developing perforated photographic films - Google Patents

Abstract

Device for developing perforated photographic films. The invention relates to a device making it possible to develop perforated photographic films automatically, whilst using the minimum amount of processing product. The device consists of a succession of vats A, whose capacity is decreased by a volume B. The whole is surmounted by a succession of sprockets D which drive the film through the various vats.

Description

 a) A miniaturized device called "MICROLAB" for developing perforated photo.raphic films.

 b) Application in all areas requiring the processing of photographic films.

 c) The current treatment principles present a huge disproportion between the volume of treatment bath and the volume of the product to be treated; in this case the photographic film.

d) This device makes it possible to circulate the film in the various baths necessary for the treatment without it being necessary to draw it there, and to develop the films with the strict indium of treatment product because of the particular shape of the tanks. . Each tank is in fact a sheath serving both as a container for the bath and as a guide for the film. This sheath is in "U" shape, the film pushed on one side goes up obliviously on the other. The film is transported by wheels notched to the standards of the perforations of the film. These wheels whose movement is synchronized, drag the film from one tank to another. The notched crown of each wheel is tangent on one side vertical to the outlet of a tank, and on the other vertical to the inlet of the next tank - drawing I
Throughout the treatment the film is guided, and is therefore only in friction on its perforated side parts, avoiding any risk of scratching on the impressed part (useful image) - drawing 2 -.

A counterfeiting at the angle of each tank makes it possible to limit the friction to the perforation strips - drawing 2 / J -. This backing is bevelled at the entrance of each tank to facilitate the entry of the film. This device using the so-called "lost bath"technique; the low c-ontenance of the tanks makes it possible to use doses of product corresponding to the doses of regenerative product usually necessary for the treatment of each film - drawing I - To obtain the particular for-ae of the tank, it consists of two parts:
- a female part A in the shape of "U"
- a male part B which marries the female part after deduction of sufficient space for the film and the treatment product to be preserved. To preserve this space, the maIe part (B) which is simply immersed in the tank (A), presents a vertical tab (I) on its rear surface. A vertical groove (H) in the tank (A) will serve as a lateral and depth guide for this tongue (T).

 e) Presentation of the drawings.

Drawing nO I: Sectional view of the device
A: Treatment tanks
B: Volume immersed in each tank to reduce the capacity as much as possible.

 C: Bain-marie now all the temperature tanks.

 D: Synchronized notched wheels ensuring the advance of the film.

 E: Film guide block during its passage from one tank to another.

 F: Film.

 G: Charger.

 Drawing nO 2: Exploded view of a tank showing the volume of useful bath remaining when the full part B has been introduced into tank A.

 The film is guided on its perforated side parts. At the entrance of the tank the slides are bevelled to facilitate the entry of the film.

 f) The device used to develop photographic films mainly consists of several tanks, the number of which depends on the desired treatment (generally three tanks). The principle consists in circulating the film in these different tanks, without any other vector than the film itself.

 For this, the device consists first of all of a charger (G) in which the film (F) to be developed is placed, leaving about 4 cm of anore sticking out through a felted slot provided for this purpose. (The original charger can be used directly provided that the device is fitted with an automatic cutting system at the end of the film).

 It is obvious that this operation takes place away from light.

 The next part is the film transport element (T). It is made up of a succession of Picot wheels (four wheels for three tanks) and guides which force. the film to follow a determined path, that is, on the one hand to match the diameter of the studded wheels, on the other hand to enter each tank successively.

The charger (G) is placed in alignment with the assembly (T)
Transport, taking care that the first perforations in the film are felt on the pins of the first wheel.

 The wheels are set in motion and the film engages in the device.

 After a quarter turn the film plunges into the first tank.

 All four wheels must rotate at the same speed.

 The treatment time in each tank will depend on the one hand on the speed of the motor, on the other hand on the depth of each tank.

 The film descends into the tank, it is impregnated with the first treatment product, at the bottom of the tank it makes a U-turn and goes up towards the top of the tank, there it is taken up by the second pin wheel which guides it towards the second tank and so on until the exit of the last tank.

 At the end of the treatment, a drying circuit can be provided at the end of which a housing will receive the film which will be wound up without an axis like a tape measure in its case.

 g) The entire device, apart from the electrical part, is made of plastic to avoid corrosion due to the photographic baths used.

 The manufacturing will therefore be done by molding, thermoforming or any other process for working the plastic material.

 The modular process design makes it possible to design standard modules adaptable according to the development processes used.

Claims (4)

 R E V E N D I C A T I O N S  I) Device for developing perforated photographic films, characterized in that it consists of a feeder (G) receiving the film to be developed (F) placed in the alignment of the film transport element (T) made up a succession (n) spiked wheels (D) and guides for the path of the film in the direction of (nI) treatment tanks (A), each tank being a corridor folded in "U" in its length, positioned vertically and flattened,  2) Device according to claim I, characterized in that the necks; dormice (A) are provided with side rails for guiding the film by its margins of perforations.  3) Device according to claim I or 2, characterized in that the treatment tanks are made from u: ie female part (A) in the shape of "U" and a nartie (B) cooperating with the latter by creating a space for the film to pass through and for receiving the treatment product: t, the part (B) further having a vertical strip (I) on its rear surface cooperating with a vertical groove (H) in the tank (A ) to serve as lateral guide and roeofonc'oi during the insertion of the part (B) in the part (A)  4) Device according to any one of reventicatiolls I to 3, characterized in that all of the treatment tanks (A) are kept at constant temperature in a water bath (C)