US2099159A - Developing apparatus - Google Patents

Description

Nov. 16, 1937. BUSSE 2,099,159

DEVELOPING APPARATUS Filed July 9, 1936 2 Sheets-Sheet l Ki l] m 1H F'e rdinand B as se /n venfor By His Afforneys Nov. 16, 1937. BUSSE 2,099,159

DEVELOPING APPARATUS Filed July 9, 1936 2 Sheets-Sheet 2 lnvenfor By His AfforneysMjr g W1 Ferdinand Bu B M 0 '0 |o J. v 9 v rm a E 6 'LI AT 7 w WQ L m 6 Patented Nov. 16, 1937 UNITED STATES PATENT OFFICE G. Farbenindustrie Aktiengesellschaft,

Frankfort-on-the-Main, Germany Application July 9, 1936, Serial No. 89,718 In Germany July 12, 1935 '1 Claims.

This invention relates to a developing apparatus and more particularly to an apparatus for use in the daylight development of roll films. Further details will be seen from the specification following hereafter.

Hitherto the efforts of manufacturers have been mainly directed towards producing an apparatus whereby the amateur could develop films himself in daylight. For this purpose it has, for example, been proposed to provide a developing tank with a light tight ante-chamber which receives the loaded spool, the film being then introduced into the tank by withdrawing the protecting paper. In order to obtain satisfactory development of the roll film in these known daylight developing tanks it is necessary to observe a number of precautions with the utmost care, particularly in introducing the film and leading it into the spiral grooves of the tank. Disadvantages of this apparatus are the difficulty of removing air from the surface of the film and the necessity for carefully cleaning and drying the tank after each film has been developed. The use of such apparatus is therefore very troublesome, and involves considerable waste of time compared with that required by an operator in a developing depot.

The demand for a daylight developing apparatus for use in the developing depot has recently become very great, since owing to the increase in the sensitivity of films only a very feeble light is permissible in the dark room. In fact already many operators place highly sensitized films in the developing apparatus (clips, frames or tanks) in total darkness. It is obvious that working in total darkness is diflicult and involves waste of time, and further that it is very diflicult to identify the film.

Since tanks are almost exclusively used for developing films, a process for introducing the film into and extending it in the tank has been devised in which the apparatus, for example tanks, clips and frames, already existing in developing depots can be used. It is well known that the most essential characteristic of the developing in tanks is the fact that the film is kept 7 extended while it is submerged in the developing bath. Daylight developing tanks are known in which the film is drawn into the tank by a weight, but these necessitate that the unexposed ends of the film be of considerable length.

This method becomes difllcult when films having very short unexposed ends, such as are customary at present, are used, since the attachment of a weight or the clamping of anend is no longer possible in the hitherto known manner, Furthermore it is necessary to submerge the whole length of the film in the developer, so that the parts of the apparatus by which the film is guided and stripped come into contact with the developer. It is therefore necessary to clean and dry the apparatus very thoroughly after each introduction of a film since otherwise the film could not be unwound. Furthermore in the known apparatus clips must be fastened to the developed and washed film in a rather inconvenient manner in order that they may be hung V ing tank. After releasing a stop the film is a passed into the developer by, for example, again pulling the protective paper, and the upper waste end of the film is gripped by a film clip after actuating a light lock. After marking the end of the film light is excluded, and the film is lowered together with the whole of the upper clip into the developer. The apparatus for carrying out the process comprises mainly a device in the passage through which the film passes from the ante-chamber, by which the chamber can be closed light tight leaving the waste end of the film free. This closing device can be opened so wide that the film together with the clip can be lowered through the passage into the developer. The light-lock may consist in lids or flaps hinged to the ante-chamber which are operated alternately with the closing device. A front part is also hinged to the upper lid which carries a device for lowering the film when attached to the upper clip. The closing device consists preferably in a spring-actuated arm which can be arrested in intermediate positions so as to produce openings of different widths.

The advantages of this novel method and apparatus are mainly that the film is protected from light while it is introduced into and extended in the first bath, and that the same method of extension is used as that employed hitherto for suspending the film in subsequent baths. Further, only the usual film clips need be attached The invention is illustrated by the accompanying drawings in which:-

Fig. 1 shows a longitudinal vertical section through the developing apparatus, comprising the tank carrying the ante-chamber and the film.

Fig. 2 is a side view of the ante-chamber,

Fig. 3 is a detail view of the guide and stripping spring,

Fig. 4 is a plan of the ante-chamber,

Figs. 5-8 are sectional views showing the method of introducing the film into the tank.

In Fig. 5 the spool has been placed in the chamber and the end of the film has been withdrawn as far as the stop, the closing arm being in open position and the base plate closed. The open position of the lid is shown in dash lines.

In Fig. 6 the closing arm has been closed, the base opened and the film gripped by a weighted clip.

In Fig. 7 the chamber is in position on the lid of the tank, with the closing arm open and the film lowered as far as the point where it is stuck to the protective paper.

In Fig. 8 the chamber has been opened and the closing arm shut.

The apparatus necessary for the extending operation consists in the following parts.

The tank 2 contains the developing bath i and is covered by a lid 3 in which a number of tubes i are supported. The tubes 4 which are open at their both ends can move to a limited extent in a vertical direction between the lid 3 and the stops 5a, and do not extend quite to the bottom of the tank 2 so that developer can diffuse freely up the tubes. They are made of opaque material, for example, thin celluloid, and have an oval cross-section with a major axis approximately equal to the breadth of the films, which are stretched inside them. Their upper ends are firmly fixed in strong moulded supporting members 5. Each tube 4 can be closed in a light tight manner by means of an ante-chamber which is easily placed on the member 5 and comprises a middle part 6, a lid I and a base 8 hinged together. The middle part 6 comprises a spool holder 6a a flexible film stripping plate 9 and'a closing arm I0 which can be actuated from outside the chamber and in the vertical position, forms a passage (see Fig. 5), but in the closed position presses against the plate (see Fig. 6) 9. The base of the middle part 6 has grooves 61) which correspond with shoulders 5b on the member 5 and 8a on the base 8 of the chamber. The engagement of these grooves and shoulders provide a light tight connection. The base 8 is hinged at 81) to the middle part 6 and can be held in either fully closed or fully open position by springs. The lid 1 is hinged at Ia to the middle part 6, protecting it from light. The lid I consists of two parts, front part lb and a rear part I, which are hinged together by a light tight hinge lc. In the light tight closed position of the lid I, lb the rear part 1 forms the upper half of the spool holder 6a. A narrow slit ll, through which protective paper I20. can be drawn, is formed between the middle part 6 and the front part 1b of the lid when this is closed. The two parts of the lid 1!, lb together form a hollow space in which a film clip M of the usual type hangs from a hook 18 on a flexible cable i3 which enters through the front part lb. In order to attach the clip M to the cable l3, the front part lb is opened. By means of the cable IS the film clip i l can be moved up and down in the hollow space and the film passage l5.

By means of the described ante-chamber the film is extended in the developing tube l in the following way. The ante-chamber is taken in the hand, the base 8 is closed and the lid ii is opened by turning it on its hinge la. Then the spool it carrying the film i2 is placed in the spool holder to, whereupon, the upper end of the flexible film stripping plate 9 bears on the roll spool. After closing thelid l, lb the protecting paper 62a is drawn through the slit I l in known manner. Also in known manner, the film i2 is unwound against the plate 9 and, in consequence of its tendency to roll up, it slides into the film passage it against the plate 9 until it touches the stop to formed on the base 8, (see Fig. 5). Meanwhile a pin Mic formed on the arresting arm illb, which is fixed outside the chamber to the axle of the closing arm it, has been in contact with a recess be on a spring 8d which is attached to the base t, whereby the closing arm it is held in such a position as to reduce the film passage between the arm l0 and the plate Q to a narrow dimension. A considerable resistance is then suddenly experienced to the withdrawal of the paper which has hitherto been easy. Before withdrawing the paper strip further, the spring illa which is tensioned when the passage is free and is situated behind the arm ill is released from outside by releasing the pin lilc from the recess 8e. This is easily effected sincethe spring M on which the recess Be is formed can be readily brought out of engagement with the pin lilo by pressing with the finger. After release, the closing arm [0 presses against a definite position of the film end, which is lying against the plate 9, so as to form a light tight closure of the spool chamber with respect to the base 8 (see Fig. 6).

If the hinged base 8 is now opened, light falls only on the end of the film which has not been used for the exposure. A film clip lI weighted with a lead weight Fla is clipped on this end of the film. For this purpose the stripping plate 9 is shaped as shown in Fig. 3, so that the teeth of the clip can easily and securely grip the film. The ante-chamber is now placed, with its base 8 in the opened position, on the supporting member 5, the shoulders 5b of which engage the grooves 612 to provide a light tight connection. The clip il now projects into the tube 4. The closing arm I0 is now rotated by turning the lever li'lb until the projection lllc engages the recess 60 in the spring 6d and the protective paper is further withdrawn (see Fig. '7), whereby the stretched film is unrolled into the tube 4 and the developer contained therein. The unrolling is continued until the point at which the film is stuck to the protective paper, when the edge 6c of the slit ll prevents further movement (see Fig. 1). The closing arm I0 is again turned to press the other film end against the stripping plate 9, the chamber is opened by raising the lid I, lb and the protecting paper I20. is torn off at the point of adhesion with the film (see Fig. 8). After marking the upper end of the film, the front portion lb of the lid is rotated about the hinge 1c and a film clip I4 is hung on the hook [8 of the cable ii. The clip M is attached to the upper projecting end of the film which like the lower end, has not been used for exposure and will not therefore be damaged by light. The front part lb is now returned to its normal position, and the chamber is thus closed light-tight. The closing arm I is again rotated away from the film. The weight of the loaded clip I! now pulls the end of the film, together with the clip ll, into the developing bath as far as the length of the cable i3 permits. This length is such that the end of the film and a part of the clip are immersed in the bath for all normal variations of the liquid level, while the hook i8 does not come into contact with the liquid. The part of the cable l3 remaining outside the lid 1, 1b serves the purpose of indirectly controlling the position of guiding the end of the film into the bath from outside, since if the upper clip it sticks anywhere in the film passage formed in the middle part 6 it can be shifted by raising or lowering the cable. As is well known, the film must be moved from time to time during development. This is done by moving the tube 4 together with the antechamber vertically up and down by means of the member 5. Stops 5a ensure that the tube is not drawn further out of the bath than is necessary.

When the film is developed, the ante-chamber with the film is lifted somewhat from the end of the tube, the clip I4 is removed from the hook I8 and the ante-chamber, no part of, which has come into contact with the liquid, is laid aside. The clip I4 is hung on a developing frame of the usual type, and the whole film is lifted from the tube and put into the next tank, whence it follows the usual course to the drying chamber. This method of withdrawing the film from the bath can be employed only if the film is desensitized by the developer. If the film is introduced with protection from light only into the desensitizing and developing bath, the whole developing process can be carried out in a well illuminated. developing room, and necessitates only a small addition to the existing tank developing equipment. For working in full daylight it is neces-- sary to provide means at the lower end of the tube which will make it possible to close the tube light tightly while it is transferred from one tank to the next. The arrangement of a separate tube for each ante-chamber has the advantage that the films can be introduced separately without exposure of the films already in the bath.

What I claim is:

1. An apparatus for developing roll film at daylight which comprises a tank for a developing bath, a tube in said tank, means for carrying said tube, an ante-chamber removably mounted on said means and carrying said film, a clip attachable at the advance end of the film for drawing the film into said tube, and a clip attachable to the upper waste end of the film for supporting the film in stretched condition in said tube.

2. An apparatus for developing roll film at daylight which comprises a tank for a developing bath, a tube in said tank, means for carrying said tube and an ante-chamber removably mounted on said means for carrying said tube, said antechamber comprising a roll film spool-holder, means to exclude light from the picture part of an unwound film while not protecting the short lengths at the ends of the film against light, clips for gripping said ends of the film and means to introduce the film together with said clips into said tube in the developing tank.

3. An apparatus for developing roll film at daylight which comprises a tank for a developing bath, a tube in said tank, means for carrying said tube and an ante-chamber removably mounted on said means for carrying said tube, said antechamber comprising a middle part, a bottom part and a lid hinged to said middle part.

4. An apparatus for developing roll film at daylight which comprises a tank for a developing bath, a tube in said tank, means for carrying said tube and an ante-chamber removably mounted on said means for'carrying said tube, said antechamber comprising a middle part, a bottom part and a lid hinged to said middle part, a closing arm and a stripping plate in said middle part, said middle part together with said bottom part, said lid, said closing arm, and said stripping plate forming a light lockfor protecting the exposed part of a roll film from light and clips for gripping the short waste ends of the film.

5. An apparatus for developing roll film at daylight which comprises a tank for a developing bath, a cover for said tank, a tube of opaque material open at both ends in said tank, a supporting member slidably held by said cover of the tank, said supporting member being fixed to the upper end of said tube, stops on said supporting member to limit the sliding movement thereof, an ante-chamber removably mounted on said supporting member, said ante-chamber comprising a middle part, a bottom part and a lid hinged to said middle part, shoulders in said supporting member, recesses in said middle part of said ante-chamber to engage said shoulders in order to form a light tight connection between said supporting member and said middle part.

6. An apparatus for developing roll film at daylight which comprises a tank for a developing bath, a cover for said tank, a tube of opaque mat'erial open at both sides in said tank to receive a roll film, a supporting member to which the upper end of said tube has been secured, said supporting member being held by said cover, an ante-chamber removably mounted on said supporting member in a light tight manner, said ante-chamber comprising a bottom part, a middle part, and a lid, said bottom part being hinged to said middle part so that it may be opened when said middle part is put on said supporting member, shoulders formed in said bottom part, recesses formed in the lower wall of said middle part to engage said lugs in the bottom part to form a light tight closure when said ante-chamher is removed from said supporting member and the bottom is closed, a groove in said bottom part to form a stop for the film, said middle part having a roll film spool holder, said middle part and said lid forming a slit to pull the protective paper of the film out of said ante-chamber, a stopping member at the inner end of said passageway to stop the film when the point at which the film is stuck to the protective paper contacts said member, a stripping plate cooperating with said roll film holder, a closing arm hinged to said middle part, means to rotate said closing arm from outside the ante-chamber, means to stop said closing arm in fully open position so that said closing arm together with said stripper plate forms a passage wide enough to let a film clip pass, means to stop said closing arm in intermediate position so that said closing arm together with said stripping plate forms a passage wide enough to let a film pass, means to hold said closing arm in closed position so that said closing 'arm presses against said stripping plate so as to close the passage between said closing sage of the middle part, a flexible cable in said passage introduced through the top wall of said front part, a hook at the end of said cable, a

film clip attached to said hook for clamping the rearward end of the film after said front part oi said lid has been opened, said cable being long enough to introduce the film end together with the clip into the developing bath.

7. An apparatus for developing roll film at daylight Which comprises, a tank for a developing bath, a cover for said tank, a tube of opaque material open at both ends in said tank to receive a roll film, a supporting member to which the upper end of said tube has been secured, said supporting member beingslidably held by said cover, an ante-chamber removably mounted on said supporting member in a light tight manner, said ante-chamber comprising a bottom part, a middle part and a lid, said bottom part being hinged to said middle part, recesses in said middle part, shoulders in said supporting member to engage said recesses and to form a light tight connection between said middle part and said supporting member after said bottom part has been opened, said middle part comprising a roll film spool holder, a stripping plate cooperating with said roll film spool holder, a closing arm,

said closing arm and said stripping plate forming a passage, an axle fixed to said closingv arm, said axle being Joumalled in opposite walls of said middle part, a spring fixed to said closing member and to said middle part forcing it against said stripping plate to close said passage, means to rotate said closing arm from outside the antechamber and to stop it in difierent positions, said means comprising a bell crank lever outside the camera fixed in its middle part to said axle, a projection on one end of said lever, foil springs at the outer wall or said ante-chamber, a recess in each of said foil springs to engage said projection and stop said closing arm when rotating the lever against the force of said spring, said coil springs being mounted in such a way that they can be depressed to disengage said projection from said recess, said lid of the antechamber being hinged to said middle part so that it may be opened to insert a roll film spool, said lid comprising a front part and a rear part, said parts being hinged together and forming a passage in closed position aligned with said passage of the middle part, a-fiexible cable in said passage introduced through the top wall of said front part, a hook at the end of said cable, a film clip attached to said hook for clamping the rearward end of the film after said front part of said lid has been opened, said cable being long enough to introduce the dim end together with the clip into the developing bath.

FERDINAND BUSSE.

Images