FR2474707A1 - PHOTOGRAPHIC DEVELOPER FOR SENSITIVE PAPERS - Google Patents

Abstract

TO CIRCULATE A LIQUID FROM A RESERVE TANK 10 TO A TEMPERATURE REGULARIZATION TANK, A PUMP BLADDER 22 IS ARRANGED AT THE BOTTOM OF A CYLINDRICAL CHAMBER 23 AND IS CONNECTED BY A VERTICAL SHAFT 29 TO AN ELECTRIC MOTOR 19 LOCATED ABOVE A LID 17. THE LIQUID ENTERING AXIALLY THROUGH ORIFICES 25 FALLS INTO THE TANK BY PASSING THROUGH A TANGENTIAL CHANNEL 24, AFTER BEING RAISED INSIDE CHAMBER 23.

Description

The invention relates to a device for developing

  photographic for sensitive papers, films

  and the like comprising a circulating bath for regulation

  increase the temperature of the reaction products contained in the device, a rotary development drum,

  reserve bottles and test tubes, which

  tif has a circulation pump, the radial impeller of which is placed in a pump casing with axial inlet for the bath liquid and is driven by an electric motor, which inlet is connected to a reserve bowl for the liquid, equipped with '' an adjustable heating which can be covered, while the

  liquid outlet from the bath out of the pump housing

  mouth in a temperature control tank which receives

reaction products.

  Development devices are known in which the circulation pump, driven by an electric motor, is connected by flexible hoses to the reserve bowl or to the temperature regulation tank. Such circulation pumps are expensive since they require a leaky pump housing and the electric motor drive must instead be sealed. In addition, with such circulation pumps, it is difficult to correctly measure the temperature of the liquid introduced into the control tank, such a measurement being made with considerable errors due to the heat losses which occur. The constancy and the accuracy of the temperature are of the greatest importance to obtain the exact nuances during

  development of color films.

  The invention aims to create a device

  development, of the kind defined in the preamble, which

  provides, with an economical circulation pump and safe operation, impeccable regulation of the

  temperature of the reaction products.

  According to the invention, this object is achieved essentially by virtue of the fact that the outlet is constituted by a cylindrical wall extending axially the open pump housing; that the impeller shaft crosses -O axially the cylindrical wall and leads to a motor

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  electric located above the bowl cover and the cylindrical wall forms with the pump housing a mixing chamber for the bath liquid which is raised axially there, and has at its upper end an outlet passage oriented transversely. Thanks to the axial connection which is made according to the invention between a mixing chamber and the centrifugal pump with vertical axis, a mixer or agitator is obtained, the movable member of which is constituted by the impeller of the pump. The pump casing, which receives the accelerated particles of liquid by rotation and which delivers them into the tangential outlet channel, is not here closed on all sides but is extended upwards by the cylindrical wall. The impeller picks up the liquid arriving axially, accelerates it and sets it in rotation. The rotating liquid causes the formation of a paraboloid of revolution in the mixing chamber of the upper edge from which the liquid then escapes. For this purpose, the impeller need only have a flange and

  radial blades carried by this flange. According to a construct-

  rationally, the impeller can be opened downwards and put the liquid in rotation, accelerating it as soon as it enters. With the dish thus created, it suffices to provide, at the upper end of the mixing chamber, an outlet or overflow passage oriented transversely to allow a liquid departure. The liquid entering axially from below is thus

raised and put into circulation.

  By escaping from the mixing chamber, the liquid finds a transverse outlet channel which has a notable section and thus offers a much weaker resistance to the flow than the narrow flexible pipes of the known solution. In addition, the path followed by the liquid is much shorter. After being raised, the liquid drops free into the temperature control tank. On this journey, no energy is

  required from the pump to overcome resistance to straining

  lement. The pump therefore only needs a low power

  nominal which is used exclusively for raising the liquid.

  According to the invention, the elevation of the liquid is however accompanied by a strong swirling.

  in an agitator, which produces uniformity

  made of temperature. Such standardization is im-

  load-bearing because the reserve bowl contains a coil

  heating which must in no case cause the appearance of

  tion, in this bowl, of layers of liquid having different temperatures from each other. This is

  why the heating coil is preferably available

  placed all around the suction opening of the pump housing, inside the reserve bowl. The

  liquid sucked in by the impeller is thus removed di-

  directly in the vicinity of the heating coil, which

  creates flow conditions favoring heating

uniformly uniform bath liquid.

  According to an improvement of the invention, means are added in the mixing chamber to influence the flow of the liquid from the bath. Preferably, these means are constituted by a temperature probe, arranged transversely to the direction of flow. The temperature sensor, causing resistance to flow, can! disposed in a housing of the bowl cover and located approximately in an axial plane relative to the axis of the impeller. In * or in full

  variant /, the aforementioned means are constituted by ai-

  fixed lettes, oriented in the direction of flow

  desired and in particular having a helical shape.

  The rotation of the liquid in the meteor chamber

  Lange is thus advantageously used to measure the temperature with a probe which plunges from top to bottom into the moving liquid, at the top of said chamber. The flow of liquid from the bath breaks on this probe, all around which it forms

  thus a turbulent flow, which ensures a balanced

  optimal brage of the temperatures on the probe and limit to

  minimum measurement errors from the graph

  temperature in the material of the probe and its support. The probe is thus bathed over a great length by the liquid which rises while turning. As it dives in the immediate vicinity of the opening of the outlet channel, the temperature sensor accurately assesses the temperature prevailing on the development drum in the temperature regulation tank. In addition, since it is placed at the opening of the outlet channel,

  the temperature sensor acts to break the flow

  and has the effect of diverting a mass of liquid towards

the output channel.

  The invention can be implemented in a particularly economical manner. This is how the problem of sealing the pump shaft towards the inside of the motor as well as towards the outside is solved by the

  mounting of this motor above the bowl cover.

  The shaft of the impeller crosses the distance between this impeller and the motor. No liquid arrives at the place which should be sealed on the lid

  of bowl. The place where the impeller shaft trav-

  pours this cover can therefore be constituted by a simple bearing or sleeve. The motor is thus placed in a zone situated above the bowl cover, zone which is intended to accommodate other electrical components and their connections with the control console and which has

  already been used for this purpose.

  According to a particularly economical embodiment, the mixing chamber is formed, at its upper part, by the side wall of a housing

  formed in the bowl cover and, at its part

  which includes the pump casing constituting it has a bottom, by an attached part whose bottom / orifices

  allowing the axial arrival of the liquid.

  Thanks to this divided construction of the

  bre, the large surface bowl cover and the insert part of the mixing chamber can be made by separate operations, with simpler tools, and then assembled in one

operational unit.

  At least certain parts of the outlet channel can be made in one piece, in particular in material

  plastic, with elements of the mixing chamber.

  In particular, at least the bottom wall of the outlet passage can be formed on the insert of the mixing chamber and the other walls of this channel can be formed by an appropriate conformation of the bowl cover. To make the circulation pump safer, it is advisable (in particular in order to obtain a clean flow, as free of splashes as possible) to make tangentially start from the cylindrical wall of the mixing chamber. one of the side walls of the outlet channel and, therefore, the rotating current. The opposite wall of this channel only needs to be placed at the desired distance for the channel to have

the optimal width.

  The operation of the pump is further improved by the fact that the mixing chamber has a rounding in the intermediate zone between the bottom of this chamber and the cylindrical wall. Liquid particles which radially escape from the impeller under the effect

  of centrifugal force are thus incorporated gradually-

  the current that rises in the mixing chamber.

  To promote upward flow, the cylindrical wall can flare conically towards the opening of the outlet channel. The bottom of the mixing chamber carries a bearing which receives the shaft of the impeller, at its free end, in order to properly guide this shaft, which is of great length. This level can be

  held in place of spoke-shaped supports.

  The free end of the impeller shaft may have, on its transverse face, a hole for the engagement of a mounting rod, which facilitates the assembly of the mixing chamber and the bowl cover. , in particular to introduce said tree into

  the bearing arranged at the bottom of this chamber.

  Finally, the insert forming the mixing chamber and the parts of the outlet channel which are optionally formed on this part carry a clearance

  of connection halves, in particular of a transmission system

  cliqtuetage, whose complementary halves are formed on the bowl cover, which allows to maintain

  securely said patch.

  A particular embodiment of the invention

  tion is shown in the accompanying drawings.

  Figure 1 shows, in perspective, an arrangement

  complete photographic development product, which includes a development drum housed in a temperature control cuvette, as well as test tubes

and reserve bottles.

  Figure 2 is a section along line II-II

of figure 1.

  Figure 3 shows, in partial section, the

  inside the device housing, with the circulating pump

lation according to the invention.

  Figure 4 is a view along arrow IV of

  Figure 3, but without the part forming the mixing well

  ge. Figure 5 shows, according to arrow IV of the

  Figure 3, the part forming the mixing well.

  Figure 6 is a section along line VI-VI of Figure 3, showing the temperature probe and its attachment. Figure 7 shows the outlet of the

  outlet, according to arrow VII of FIG. 3.

  As shown in Figures 1 and 2, the

  development device is constituted in its entirety

  ble by a portable bowl 10. This is covered

  an attached shell It has on the one hand a recess

  cement serving as temperature regulation tank for a development drum 12 and on the other hand various

  seats for the storage of reserve bottles 13 and of

  test tubes 14. On the left side of figure 1, we see

  a control console 15 forming part of a sur-

  high 16 in which are housed a motor serving to

  drag the drum 12 and a circulation pump for the liquid of the temperature-maintaining bath. This raised housing 16 has a separate bowl cover 17

  which also serves as a mounting frame for the various components

  reported. As shown in Figure 2, the

  liquid level is higher in the co-

  keel It only in the bowl 10. The liquid circulated by the pump freely falls from this tank into

  the bowl 10, crossing an overflow threshold 18.

  Among the added elements which are located under the raised housing 16, FIG. 3 shows the circulation pump. This pump comprises an electric motor 19, a transmission shaft 21 provided with an impeller 22 and a cylindrical mixing well 23 with an outlet channel 24 and inlet ports 25. The outlet channel 24 is offset laterally relative to the axis

from tree 21.

  The motor 19 is carried by an attached piece, on the bowl cover 17. The shaft 26 of this motor carries a plug-in coupling 27 on which a protective flange 28 has come from injection molding. Sure

  the coupling 27 fits a tubular part 29 at the end

  lower part of which an axis 30 is pressed in, integral with the impeller 22. By the free end 31 of its axis, the impeller 22 is quidée in a bearing 32. The impeller 22 consists of a flange 33 on which radial vanes are formed 34. Downward, the impeller 22 opens in the direction of the inlet orifices

  25. The lower part of the cylindrical well 23, which

  turns the impeller 22 and which forms a pump casing open upwards, has a rounded 36 in its transition to the inlet orifices 25. At the level of the

  inlet ports 25, the bottom of the well 23 is advantageous

  equipped with a sieve or filter. As is particularly apparent from FIG. 5, the bearing 32 is maintained

  in the center of the inlet openings 25 by four spokes 37.

  On its transverse face, the free end 31 of the axis 30 of the impeller 22, which is held by the bearing 32, has an axial hole 38 o can be engaged a mounting rod to facilitate the introduction of this end

free 31 in bearing 32.

  By its upper edge 40, the cylindrical well

  that 23 which ends at its lower part in the pump housing 35 is engaged in an appropriate housing (see in particular FIG. 4) which for this purpose comprises the bowl cover 17. By this upper edge 40, the insert constituting the well 23 abuts against a

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  narrow rim 42 formed on the periphery of said housing (see FIG. 4). This housing of the bowl cover 17 is dimensioned such that the cylindrical well 23 is extended by a cylindrical side wall 41 which is part of this housing. One of the side walls 44 of the outlet channel 24 leaves tangentially from

  this cylindrical wall 41 (see Figures 3, 4 and 7).

  In this housing of the bowl cover 17, the upper wall 43 of the channel 24 has various slopes at the

like a roof with cut sides.

  The lower wall 45 of the channel 24, formed in one piece with the well 23 (see FIGS. 3 and 5), is located in the same plane as the upper edge 40 of the

  well 23 and ends with a discharge threshold 46.

  This lower wall 45 is connected to the cylindrical well by a slope 47 and is supported by lateral tabs 48 which reach the cylindrical wall 41 of the well 23. By an end partition 49, the lower wall 45 is connected exactly to the contour outside of the bowl cover 17. A latching system is provided for immobilizing the well 23 in its housing of the bowl cover 17. This system has two opposite spouts 50 on the cylindrical wall 41 of the housing and two cams

  corresponding 51 on the upper edge 40 of the well 23.

  When the well 23 is introduced, the latter deforms slightly at its upper edge 40 and it is held in place by an elastic snap-on effect (see the

figure 6).

  The part 20 which is attached to the housing of the bowl cover 17 and on which the motor is fixed

  electric 19 includes two parallel legs 60 that

  pour bolts used to fix this motor (see in particular Figure 3). Between these two legs 60 is placed a cylindrical sleeve 61 which serves as a passage for the motor shaft 19. In the interval-between the legs, two oblique partitions 62 are connected symmetrically to this sleeve 61 as it emerges in particular from the Figure 6. A temperature probe 63 passes through one of these oblique zi osns 62, through a rubber seal 64 The temperature probe C3 enters the well 23 to below the upper edge 40 thereof . As is particularly shown in FIG. 4, the hole through which the temperature probe 63 passes through ia

  oblique partition 62 is located opposite the side wall

  line 44 which is tangent to the outlet channel 24.

  Thanks to its location

  fogging, the temperature probe 63 breaks the mass of liquid which is rotated in the well 23 by the impeller 22. This probe 63 is therefore always well bathed in liquid flowing at high speed. It breaks the flow in front of the outlet channel 24 and has the effect of diverting through this channel 24 a current drawn from the

bath liquid.

  In order to promote the pumping action, the cylindrical well 23 may comprise, on its internal wall and in the vicinity of the pump housing 35, fixed fins oriented in the desired flow direction and

  having for example the shape of propellers.

  As shown in Figure 3, a ser-

  heating pin 39, which is shown in section, is mounted on the bottom of the bowl 10, around the group of

  inlet ports 25 formed in the pump housing 35.

  This coil 39 can be constituted by a tubular system

  closed area in which an electrical resistance is threaded

  helical heating stick. The impeller 22 sucks the liquid directly in the vicinity of the coil 39. Inside the mixing chamber constituted by the well 23, there is an equalization of the temperatures under the effect of the strong vortices to which is

subject the liquid.

2474707:

Claims (15)

  1. Photographic developing device for sensitive papers, films and the like comprising a circulating bath for regulating the temperature of reaction products contained in the device, a drum   rotary development, reserve vials and proofs   which device includes a circulating pump   tion whose radial impeller is disposed in a pump housing with an axial inlet for the bath liquid and is driven by an electric motor, which inlet is connected to a reserve tank for the liquid,   equipped with adjustable heating and likely to be-   covered, while the outlet of the liquid from the bath out of the casing. pump opens into a regulation tank   temperature which receives the reaction products, characteristic   risé in that the outlet is constituted by a cylindrical wall (23) extending axially the open pump housing (35) .- in ct that the shaft (21) of the impeller axiàlemen (22) crosses / the cylindrical wall ( 23) and results in an electric motor (19) located above the bowl cover (17) and in that the cylindrical wall (23) forms with the pump housing (35) a mixing chamber, for the liquid of the bath which is raised axially there, and has at its upper end (40) an outlet passage (24) transversely oriented.   2. Development device according to claim 1, characterized in that the section of the cylindrical wall   corresponds to the contour of the pump housing (35) .-   3. Development device according to one of the re-vendica-   1 and 2, characterized in that the cylindrical wall (23) widens conically towards the opening of the passage of outlet (24).   4. Development device according to any one of   Claims 1 to 3, characterized in that the room   of mixing is constituted, in its upper part by the - cover of.   side wall (41) of a housing formed in the / bowl   (17) and, at its lower part which includes the housing -.   pump (35) by constituting a bottom, by a part   bearing surface (23) the bottom of which has holes (25) per-   putting the axial arrival of the liquid. 2474707.   1.1 5. Development device according to any one of   claims 1 to 4, characterized in that the bottom of the   mixing chamber (23) carries a bearing (32) which receives the shaft (21) of the impeller (22), at its free end (31). 6. Development device according to any one of   Claims 1 to 5, characterized in that the chamber   of mixing has a rounding (36) in the intermediate zone   area between the bottom of this chamber and the cylindrical wall that (23).   7. Development device according to any one of   claims 1 to 6, characterized in that the bottom of the   mixing chamber is fitted with a level filter or sieve inlet ports (25).   8. Development device according to any one of   Claims 1 to 7, characterized in that the passage of   outlet provided on the cylindrical wall (23) is constituted by an outlet channel (24) which is offset laterally with respect to the axis (21) of the pump and of which a side wall   (44) is tangent to the cylindrical wall (23).   9. Development device according to claim 8, characterized in that at least certain parts of the channel   outlet (24) are made in one piece, no-   so much plastic, with elements of mixing chamber.   10. Development device according to one of the claims   cations 4, 8 and 9, characterized in that at least the bottom wall (45) of the outlet channel (24) is formed on the insert (23) of the mixing chamber, and   the other walls (44, 43) of this channel (24) are constituted   killed by an appropriate conformation of the cu vette (17).   11. Development device according to any one of   claims 1 to 10, characterized in that means are   reported in the mixing chamber (23) to influence the flow of liquid from the bath.   12. Development device according to claim 11, characterized in that the above means consist of a temperature probe (63), arranged transversely by   relation to the direction of flow. 2474707 '   13. Development system according to all of the   vendications 4 and 12, characterized in that the probe   temperature (63), causing resistance to the   Lement, is arranged in a housing of the cover of cu-   vette (17) and located approximately in an axial plane   relative to the axis (21) of the impeller (22).   14. Development device according to claim 11, characterized in that the above means are constituted   by fixed fins, oriented according to the direction of flow   Lement desired and having in particular a helical form.   15. Development device according to any one '   of claims 1 to 14, characterized in that the part   insert (23) forming the mixing chamber and the parts of the outlet channel (24) which are optionally formed on this part (23) carry a set of connecting halves (50, 51), in particular a system of snap-in, the complementary halves of which are provided on the cover bowl (17).   16. Development device according to claim 5, characterized in that the free end (31) of the shaft (21) of the impeller (22) comprises, on its transverse face,   a hole (38) for engaging a mounting rod.