CA1058935A

CA1058935A - Automatic replenisher system for a film processing tank

Info

Publication number: CA1058935A
Application number: CA242,657A
Authority: CA
Inventors: Ralph L. Charnley; Alfred J. Gaskell
Original assignee: Pako Corp
Current assignee: Pako Corp
Priority date: 1975-06-25
Filing date: 1975-12-29
Publication date: 1979-07-24
Also published as: US4057818A; AU8793275A; SE7514723L; FR2315713A1; NL7515113A; IT1052648B; DE2559026A1; FR2315713B3; BE837127A; JPS524831A

Abstract

AUTOMATIC REPLENISHER SYSTEM FOR
A FILM PROCESSING TANK

ABSTRACT

An automatic replenishing system for maintaining the chemical concentration of the liquid in a film processing tank, which automatically energizes a replenishing pump at regular timed intervals (e.g. every 30 seconds) regardless of whether or not the control circuitry indicates a need for replenishment, and which includes means for sending the density and velocity of the film and for producing a com-bined signal which controls the running time of the pump after each energization. The replenishing system also in-cludes a second replenishing pump for maintaining the con-dition of the liquid in the processing tank, which second pump is energized automatically after a predetermined number of said regular timed intervals, or after a predetermined number of said regular timed intervals in which a zero film density or non-use condition has been detected for a pre-set running time.

Description

~ "

~58~3S
, BACKGROUND OE THE INVENTION

This invention relates to a method and apparatus for re-plenishing the processing liquid in an automatic film processor :
` to compensate for the lowered chemical activity of the proces-sor liquid which results from the processing of the film It has been recognized in the prior art that a pre-ferred way to control the rate and amount of replenishment ~-., , supplied to the processor is to sense the image density of the film passing through the film processor and to derive an elec-trical control signal proportional to said image density which ;~ 10 controls the replenishment means for said film processor.

The prior art replenishing systems fail to energize :~
,~ the replenishing pumps unless the density measuring signal in-i dicate~s a need for replenishing liquid. Thus if the machine is inoperative for long periods of time (with no film passing ~-':;1 ,' ' -`~ through) and the processing liquid in the tank becomes in- ~
!: . .
~, effective due to oxidation, there would be no replenishment ;~

of the liquid with such equipment. These prior art systems `
, require a certain minimum quantity of film to pass through ' processors before actuation of the replenishing pumps so that ~'j 20 if a substantial quantity of!film has passed through (but less than the minimum quantity required to energize the re~
.," : ~:
1 plenishing pump) and then the processor is not used for a ¦ period of time, the condition of the processor liquid deter-,.: 1 iorates at an exponential-like rate so that it requires more ;

replenishing liquid than can be supplied by the next cycle. -.,, ., ~ , "',',: ~'

2-~L~5~393t~

This causes improper processlng until sufficient replenishing liquid is supplied to bring the condition of` the liquid back up to standard. This would necessitate manual assistance to pre-vent an unacceptable batch of filnl from being processed.
:

With the instant invention however, the replenlshingpump is automatically energized at predeterminecl time intervals (e.g. every 30 seconds) regardless of the film density, and if the density measuring system fails to call for replenishirg liquid as in the case of non-use or zero density the pump will ~ -be automatically shut off almost immediately (e.g. 20 milli-seconds). By inserting a counter to count the number of non-use or zero density pump starts, an automatic replenishment cycle can be readily provded to run a second pump for a pre-set time after a predetermined number of such non-use or zero -~
density start-stop cycles or after a predetermined number of cycles regardless of the density or use of the film and pro-cessor, respectively. ~;~

According to the invention there is provided an auto-matic replenisher system for photographic film processors of the type having at least one tank and defining a film path extending through the processor and downstream therefrom, said system comprising, a replenisher pump for supplying replenishing ~`
liquid to each processor tank, means for automatically energizing each pump at predetermined periodic intervals regardless of the density of the processed film processed in said processor, -~

light-sensitive film density scanning means positioned in the film path downstream of the processor for measuring the -~
... .
image density of the processed film and for producing an elec-- trical control signal responsive to the density of said ~ , .
processed film, comparator circuit means recèi-ving said sig-nal for comparing the same to a reference signal and controlling . .. .

3.

: ~5~3935 :, -~' the time interval said replenishment pumps are energized in response to the signal produced by said comparator means.

This invention rèlates to an improvement for this type of replenishment technique. It is an object of this invention , to provide a method and means for replenishing the processing , liquids of a film processor which is based on both the sensed ~, image density of the film and the velocity of the film through ~; said film processor.
. .. ~ ~ . -, :~ .
It is a more particular object of this invention to pro- -vide re~lenishment means to maintain the chemical activity j of the developing and fixing chemicals in the film processor ~ -when there is no film passing through the film processor or ~' when said film processor is not being used. ~-~, ~ These and other objects and advantages of this invention will be apparent from the following description made in con~
nection with the accompanying drawing wherein like reference characters refer to similar parts throughout the several ` ~ views, and in which: ;
,., ~ -. ~ .
.:, . .
'''',;! Fig. 1 is a diagrammatic side elevational view of an - ~, - ~ :
automatic film processor incorporating the;automatic replen-isher system of the present invention; ;
:...................................................................... : ,:
Fig. 2 shows diagrammaticall~ the light-sensitive den- ~-sity scanning head for measuring the image density of the film ' strip passing through the film processor; ~-~
'' Fig. 3 shows diagrammatically magnetic means for pro-ducing the electrical drive signal responsive to the speed of travel of the film through the processor;
.
Fig, 4 is a block diagram of the control circuitry of the present invention; and ,',,, ,. '

4.

~)5i3~35 , F`igs. 5, 6, and 7 are circuit diagrams respectively show-ing identified portions of the control circuitry of the inven-~ tion.

-~` DESCRIPTION OF` THE PREFERRED
; _ _ EMBODIMENTS

Referring to Fig. 1, a film processor P is shown. A ~;
' strip of film material 1 is transported by an electrical drive motor 6 and conventional conveyor means (the details of which ~ '~
are not shown) through a developer tank 2, fix tank 3 and a ~, '' wash tank 4. This developed film 1 is then passed through a light sensitive density scanning head 5 which produces a den-sity signal directly proportional to the image density of said developed film strip 1. Said density signal is then trans~
mitted to control circuit as-sembly designated by the block ;~
7 in Fig. 1, the components of which are shown in Fig. 4.
.. ~, ::, The developed film is subsequentIy transported through a ~ ' " dryer 8 and then transported out of said processor P. A
., c , .
magnetic pickup 9 having a core 9a and a coil 9b is provide~d , to produce an electrical drive signal responsive~to the speed ' '' ' ,~ ' of sald drive,-motor,6. Said-drive signal transmitted to said '' control circuit assembly 7~ which combines said drive and den~

~ sity signals to produce a se`ries of control signals each of ' ,~ which controls a period of time a first developer pump 10, ,~ a second developer pump 11 and a fix pump 12 will be énergized during regular time intervals. When said pumps 10, ll;-and 12 are energized, they replenish the chemicals contained in said '' , tanks 2 and 3 in response to the density and drive signals Referring to Fig. 2, said density sensing head 5 is, "', ~,' ~'

- 5.

:
i6)~89~5 in the form shown, comprised of a plurality of matched pairs of light-emitting diodes 13 ~LEDs) and cadmium sulfide photocells 14. The LEDs 13 and the photocells 14 are sealed respectively in liquid-tight optically transparent tubes and ~ ~`
.. :. .
are fixed in closely spaced relation to each other. Balancing potentiometers 15 are provided to match the electrical ~ ~;
characteristics potentiometers 15 are provided to match the electrical characteristics of said photocells 14. Said film material strip 1 is passed between the tubes containing said . ., ~ .
: 10 LEDs 13 and photocells 14, respectively, as shown in Fig. 1.
Said LEDs 13 are connected on parallel so that equal amounts ~-;
; of electrical current~ flow through each ~ÉD 13, thus ensuring -~ uniform light emissions. LEDs are pPe'ferable over the prior ;~
!;,:,, ~ art of using incandescent or florescent light sources in this ~ application in that LEDs are more compact, take less power to ~'r~
~' ~ operate, have a collimated light output, are less suscept-ible to vibration, emit less heat, and have a life span at ~
least as long as the other light sources. Therefore LEDs ~;
can~be positioned more closély to the film 1 with the re-sult that less power is needed to adequately sense the image density of said film 1.

- Referrlng to Fig. 3, said magnetic pickup 9 is posi-: . .
tioned in closely spaced relation to a sprocket wheel 16 ~`
fixed to the drive shaft of drive motor 6 so that the teeth of wheel 16 will pass through the magnetic field of pickup 9 and thus produce pulse signals in winding 9b. The signals so produced are then transmitted to the control circuit : .
assembly 7. ;
,...................................................................... :, .
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; 6 . .
... , , . ~,. . . .
:

~5~35 Referring to ~ig. 4, said magnetic pickup 9 is con-nected to a motor speed signal conditioner 180 Said con-ditioner 18 is shown schematically in Fig. 5, and is comprised of two nen-type transistors 50 and 51, a timer circuit 52 and an integrator circuit 53,-and associated resistors and cap-acitors connected as shown. Said photocells 14 are connected to a density signal conditioner 17, which is comprised of an operational amplifier 68 connected as a current-to-vol-;~i tage converter, and a slope inverter 69, and associated re-sistors and capacitors connected as shown in Fig. 5. Re-, ferring to Fig. 4, the outputs of said density signal con-.: ^
ditioner 17 and motor speed conditioner 18 are connected to ~, the inputs of a multiplier 19. The output of said multi-:.. ,, :
plier 19 is connected to the input of an accumulator 20.

Said accumulator 20 is comprised of an integrator circuit . ~..
81, a reset relay 390 and assorted resistors and capacitors ~ -connected as shown in Fig, 5, Referring to Fig. 4, two variable timing resistors 21 and 22 haue one end and the wiper arms connected to a ' 20 fixed voltage source and the other end connected to one pole ~, of a switch 23, respectively. The movable contact of switch .. . . .
~? 23 is connected to the input of a developing timing inte-~ grator 24. The input of a fix ~iming integrator 25 is con-,~ nected to a fixed voltage source by a variable resistor 26, `~
s as shown. A two phase reset oscillator 27 has the first ~, phase signal connected to the reset input of a sample and hold circuit 28. The second phase signal of said oscillator : ~ .
, 27 is connected to the reset inputs of said developer ciming ' ' integrator 24, said accumulator 20 and also to said fix . .-. i , . :
' ; timing integrator 25, and is connected to the first developer ~
.
,:~ ., -7~
~ : . , . ., .: :
s : : :
,.

~L~58~35 pump 10 and fix pump 12 start terminals of flip flop cir-~ cuits 29a and 29b, respectively. Said second phase sig-;- nal is also connected to the input of a counting circuit i 30, known in the electronic art as a "dlvide by 60"
counter.
.~`` ;, ~.
.. ~.
~i Referring to Fig. 6, said oscillator 27 is comprised .
of transistDrs 85, 86 and 87, a timing integrated circuit - 88, a relay 391, and resistors, capacitors and diodes con~
; nected in the manner shown. Referring to Fig. 5, said ~
sample and hold circuit 28 is comprised of a field-effect ~;
i1 transistor (FET) 110, an integrator circuit lll, and resis-~ tors and capacitors connected in the manner shown. Referring i~ to Fig. 6, said counter 30 is comprised of integrated circuit counters 115 and 116, and a resistor and capacitor ~~ connected in the manner shown.

`l~ Referring to Fig. 4, the outputs of said sample and ;~
3 hold circuit 28 and devèloper timing integrator 24 are con-nected to the inputs of a comparator 31, while the outputs . .. : : ;:- .
~ of said sample and hold circuit 28 and fix timing integrator ', a 20 25 are connected to the inputs of a comparator 32. The ;1 outputs of said comparators 31 and 32 are connected to the stop terminals corresponding to the first developer and fix pumps 10 and 12, respectively of said flip flop circuits ;
: 29a and 29b.
. ~ . .. :
The output of said sample and hold circuit 28 is con- ;`
;-~ nected to a zero density detector 35 which is in turn con-;~ nected to a zero density lockout and non-use logic circuit 8.
,:, ' ,, :

. . .

~L~5~3~35 36. Referring to Fig. 7, said zero density detector 35 is , co~lprised of an operational amplifier 119, and resistors and '-capacitors connected in the manner shown. Said flip flop circuits 29a and 29b are comprised of NAND-type devices 123, 124, 125 and 126 connected as shown. ~aid log:ic circuit 36 ~' is comprised of NAND-type devices 127, 128, 129 and 130 and diodes 131, 132 and 133 connected in the manner shown.
~''. '"
., ~, Referring to Fig. 4, an output of logic circuit 36 is connected to the enable input of said counter 30 through .: . .
10 a switch 47 as shown. An output 134 of said logic circuit 36 is connected to the input of the first developer relay '' ~ driver 37 and to a fixed pole of a switch 38, while an ,~' output 135 of said logic circuit 36 is'connected to the in-put of the fix relay driver 42 and to a fixed pole of a ~, l switch 40. The movable contact of said switch 40 is con- -nected to a fixed voltage supply. Referring to Fig. 7, '; ,~
'~ said developer relay driver 37 is comprised of a LED 160, ~-;~ transistors 161 and 140, diodes 141 and 142 and resistors ` ;
~ connected in the manner shown. Similarly constructed are ' ,~ 20 fix relay and second developer relay drivers 42 and 44, ,~
. . , . - .
- as shown. Referring to Fig. 4, the output 138 of said first ~'~ developer relay driver 3'7 is connected to the energizing -'~ coil of a first developer relay 39, and the output 139 of said fix relay driver 42 is connected to the energizing ~ ~;
coil of a relay 41. Said first developer replenishing pump `
'' 10 and fix replenishlng pump 12,are connected to the con-:.
, tacts of relays 39 and 41, respectively, in such a,way that .: ~

~ when the coils of said relays 39 and 41 are energized the ~ ,~
"~

'' 9.
, ' .
, .,, ~ , , :: ' '' . ' ' ': ,, , . ' " :

:l~S1~ 5 ,` .
respective replenishing pumps 10 and 12 are also energized.
A switch 255 has its movable contact connected to ground 7 and has one fixed pole connected to terrninal 252, which en~
ables said replenishing pumps 10, 11 and 12 to be energized at the proper time, another fixed pole connected to terminal 253, which disables said pumps 10, 11 and 12, and another fixed pole connected to terminal 254 which enables only the said second developer pump 11 to be energized at the proper time.
: j . ~ ., .
. :. ::,:

` 10 The output of said counter 30 is connected to a timing circuit 43. Referring to Fig. 6, said timing circuit 43 is comprised of a timing integrated circuit 162, equivalent to ~;~; type 555, and resistors, capacitors and a diode connected in the manner shown. Referring to Fig. 4, a variable timing ~
~l resistor 137 is connected to said timing circuit 43 in the `~ `
`~ ~anner shown. The output 135 of said timing circuit 43 is ~ connected to the other fixed pole of said switch 38 and to :. ;, :, ~
, .
the input of said second developer relay driver 44O The ~ movable contact of said switch 38 is connected to a fixed 3, voltage supply. The output 173 of said driver 44 is con-nected to the en~rgizing`coil of a second developer relay 45. Said second developer pump 11 is connected to the contacts of said relay 45 in such a way as to be energized whenever said coil of relay 45 is energized.
. . ~l ! In typical operation, when the film passing between ,~ said LEDs 13 and photocells 14 has an image density of 50%
~ (where 0% is optically transparent and 100% is opaque) an ~
: . ~

:: :
.' , ,~
10 .
: ~ , , .
. . , :
, .. . . . .

~6~58~3t~ ~

output voltage of -5 volts is produced by said density sig-nal conditioner 17. When said drive motor 6 is operating, the teeth on said sprocket wheel 16 interrupt the magnetic field produced by said sensor 9 and produce electrical pulses `-in said sensor winding 9b which are transmitted to said motor speed conditioner 18. The frequency of said pulses is directly related to the speed of said drive motor 6. The pulses are then inverted through said transistor 50, wave shaped through transistor 51 and inverted again. Timer circuit 52 is a type 555 timer connected as a monostable one shot pulse device.
Each pulse into timer circuit 52 yields a square wave pulse ;
output of constant pulse width and amplitude, but the fre-quency is still directly related to the speed of said drive motor 6. This output is then integrated through said ~ `
integrator 53~ which produces a constant output voltage -which can vary from 0 to -10 volts D.C. When said drive motor 6 is operating at 50% speed,^the output voltage is at -5 volts. The outputs of said conditioners 17 and 18 are combined by said multiplier 19, which produces a sig-nal equal to the multiple of the conditioner signals, di-.
vided by a factor of ten. Therefore, when the conditioner ~ ~`
slgnals are at -5 volts~ the output voltage of said multi-plier 19 is at ~2.5 volts. The output of said multiplier 19 is applied to the input of said accumulator 20, where it is integrated for a set time period of thirby seconds.
., :
~ Said reset oscillator 27 is a two phase oscillator : . ~. - ..
~ circuit of a type well known in the art, which produces two ~ ' ~

.

, : ~.':
. :
:

1~58~3S
`~'' . , separate timed signals. Each of these two signals consists of a twenty millisecond pulse every thirty seconds, said signals~being so timed that the phase two pulse occurs ~:~
.;:, ~ , .
.l immediately after the phase one pulse occurs.
~ . ; . ! . ' . ,~. . . .
, . .
When the phase one signal pulse is applied to said sample and hold circuit 28, said circuit 28 acquires the ;i output signal of said accumulator 20 and the output signal .~ ~ of said circuit 28 will be held at the acquired signal level ~- -~J' until the next phase is applied thirty seconds later. ;~
i: :
-,~ 10 Said phase two signal pulse is then applied to the reset inputs of timing integrators 24 and:25 and said accumu~
:;'1 : :
lator 20 which sets the output signal of said accumulator ;-~
j 20 to zero volts and to the first developer and the fix : .~ ~ ,. . .
, ,,ij : ~
~: start inputs of flip flop circuit 29O When said phase two .~ ~ signal is applied to the first develQper start input of said circuit 29a, a signal is produced and applied to the ~-," , ~
first developer input of the logic circult 36. Said logic : ; : circuit 36 then app~lies a signal to the input of relay i driver 37, which in turn energizes relay 39. Said relay ., ., ~ .
39 energizes the first developer replenishment pump 10. A
. similar operation is preformed to energize said fix pump 12.
`1 The phase two signal is applied to the fix start input of -~ circuit 29b, and said circult 29 then generates a signal `~ which is applied to the fix input of logic circuit 26. Said :~
i; logic circuit 36 then applies a signal to the input of fix ~ relay driver 42 which in turn energizes fix relay 41. Said ~; relay 41 energizes said fix pump 12. ~ .

:i :
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"
~: 12.

.~

S8~13~5 :
~' The accumulator 20, a~ter the application of said phase two pulse, again starts to integrate the output from multiplier 19 over said thirty second time period. Said timing integrators 24 and 25, after the application of said phase two pulse, initiate integration of the current pre-set by the variable timing resistors 21 or 22, depending on the position of said switch 23, and variable timing resistor 26 More pre-set currents may be made available to said in~
~, . .
tegrators 24 and 25 by the addition of more variable resis- ~`
tors in a manner similar to said resistors 21, 22 and 26.
The outpu~s of said integrators 24 and 25 are applied to in-puts of comparators 31 and 32 respectively.

The output of said sample and hold circuit 28 is applied to the other input of said comparators 31 and 32~ -When the output voltage level of developer timing integrator 24 exceeds the voltage level of the output of the sample and hold circuit 28, a signal is generated by said comparator 31 . ~ .
and applied to a stop input of flip flop circuit 29a which then de-energizes said first developer replenishing pump 10. T~hen the output voltage level of said fix timing inte~
grator 25 exceeds the voltage level of the output of said sample and hold circuit 28, said comparator 32 generates ;
, a signal which is applied to a stop input of flip flop cir-I cuit 29b, which then de-energizes said fix replenishing i , .
~`` pump 12. When there is 50% density and said drive motor 6 is operating at half speed, said pumps 10 and 12 are en-ergized for 7-1/2 seconds out of each fixed 30 second ~ime ~ :.
period. ~-The output of the sample and hold circuit 28 is also ~
~.
:

13.

~L~S8935 .' .~, .
.
applied to the input of a zero density detector 35. When a ~ -; , zero density condition is detected, or when there is no film ~'''.
passing through said developer or when the speed of said motor ~ ~:
,.'. 6 is zero (the last two conditions commonly referred to as the non-use condition), said detector 35 applies a signal : -~
;i to the zero density lockout and non-use logic circuit 36 terminal 229. This has the result of de-energizing the first developer and fix pumps 10 and 12 twenty milliseconds ~:, after energizing said pump. With manual switch 47 in the ' 10 closed position, said logic circuit 36 will generate an en-: -`.~ : able signal and apply it to said counter 30 thus advancing .~, said counter one incremen~t whenever a zero density condition ~, ~
`! : ,.
is detected, or when a non-use condition (when the signal .
output of said motor speed signal conditioner 18 is zero) . , :: :
f is detected. When switch 47 is in the elapsed (open) '!~
~J~
-~ position, said counter 30 will be advanced one increment every 30 seconds with each phase two reset pulse. When . ~ ~
.~, .said counter 30 has been incremented sixty,times, a signal .~

~ is generated by said counter 30 and is applied to the , r~ -::3 ~; 20 second developer replenishing timer 43 ? which energizes '~
relay 45 through relay driver 44, said~relay 45 energizing ;~
', the second dev,'eloper replenishing pump ll for a set period ~,~
of time determined by the variable timer control resistor` ,, ~. 137. :~

,,I, Said relay drivers 37, 42 and 44 may also be energized ~ manually by use of manual switches 38 and 40 to energize the ,,.,~ respective pumps lO, ll and 12 as long as said switches are ."'~, ~.` .
: 1 ' ,. :
-.: 14.
.
. . ~ .:
:,, : . ,, . :
,. ~
., ~ , . . .

:

93~ ~ -~ in the appropriate operating positionO
~ .

It will of course be understood that ~rarious changes ~.. ~ . .
~: may be made in the form, details, arrangement and propor-: . ~
: tions of the parts without departing from the scope ofithis : invention as set forth in the appended claims~

.,~ ~ .. .

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'''' ' ~,, ~.' ' :''.~ ~ . ., ~ ' '. ~ '~" ' ''' ' 'i ;~. ~, :' ` , ;;~, ~:

. 15, : ;, - :: .. -:

Claims

WHAT IS CLAIMED IS:

1. An automatic replenisher system for photographic film processors of the type having at least one tank and defining a film path extending through the processor and downstream therefrom, said system comprising, a replenisher pump for supplying replenishing liquid to each processor tank, means for automatically energizing each pump at pre-determined periodic intervals regardless of the density of the processed film processed in said processor, light-sensitive film density scanning means positioned in the film path downstream of the processor for measuring the image density of the processed film and for producing an electrical control signal responsive to the density of said processed film, comparator circuit means receiving said signal for comparing the same to a reference signal and controlling the time interval said replenishment pumps are energized in response to the signal produced by said comparator means.

2. The automatic replenisher system recited in Claim 1 further comprising, means for producing an electrical signal responsive to the speed of travel of exposed film through said film processor, means for combining said density scanning the film speed electrical signals into an electrical control signal, means for controlling the time interval said replenish-ment pump is energized in response to said combined elec-trical control signal.

3. The automatic replenisher system recited in Claim 1 further comprising, means for detecting a zero density condition signal from said light-sensitive density scanning means, and means for momentarily energizing said replenishment pump at said regular time intervals when said zero density signal is detected.

4. The automatic replenisher system recited in Claim 1 further comprising, means for detecting a zero density condition signal from said light-sensitive density scanning means, means for detecting a non-use condition in said film processor, and means for momentarily energizing said replenishment pump at said regular time intervals when said zero density condition signal or said non-use condition are present.

5. The automatic replenisher system recited in Claim 2 wherein said means for deriving an electrical signal res-ponsive to the speed of travel of said exposed film through the film processor comprises, a drive motor for driving said film through the processor a magnetic pickup device associated with the drive motor to produce electrical signal pulses, the frequency of which is proportional to the speed of said drive motor, and means to transform said signal pulses into an analog signal whose amplitude is proportional to the frequency of said electrical signal pulses produced by said magnetic pickup device.

6. The automatic replenisher system recited in Claim 1 wherein said light-sensitive density scanning means for measur-ing the image density of said film and for deriving an electri-cal signal responsive thereto comprises, a plurality of paired light emitting diodes and light-sensitive receiving elements in fixed relation to each other, and means for combining the electrical signals from said light-sensitive receiving elements and for amplifying the resulting electrical signal to derive said electrical signal responsive to the optical density of said developed film.

7. The automatic replenisher system recited in Claim 1 wherein said means for periodically energizing said replenish-ment pump at regular time intervals comprises, a two phase oscillator circuit, said phase signals being in fixed consecutive relation to each other, and the frequency of said phase signals determining said regular time intervals, and means for applying said second phase signal to said replenishment pump thereby energizing the same.

8. The automatic replenisher system recited in Claim 1 wherein said means for controlling the time interval said re-plenishment pump is energized in response to said electrical control signal comprises, an accumulator which accumulates said control electrical signal during said regular time intervals, a sample and hold circuit which acquires and holds the output signal of said accumulator when said first phase signal is applied to said sample and hold circuit, a timing integrator circuit which produces a pre-set reference current and integrates said reference current to produce an output reference voltage, a comparator circuit which compares the electrical con-trol signal to the output reference voltage of said timing integrator circuit and means to de-energize said replenishment pump when the output voltage level of said timing integrator circuit corres-ponding to said replenishment pump exceeds the voltage level of said control electrical signal.

9. The automatic replenisher system recited in Claim 8 wherein said timing integrator circuit comprises, a current integrator circuit which integrates a pre-set reference current, and means for selecting among a plurality of pre-set ref-erence currents and reference currents to be integrated,

10. The automatic replenisher system recited in Claim 9 wherein said means for selecting among a plurality of pre-set current comprises, a fixed independent direct current voltage source, a plurality of variable resistors which have one end and the wiper arms connected to said voltage source, and a switch which has each fixed pole connected to the other end of one of said variable resistors and the movable contact of said switch connected to the input of said current integrator circuit.

11. The automatic replenisher system recited in Claim 4 further comprising, an ancillary replenishment pump for supplying a re-plenishing fluid to said film processor, counting means which is advanced either by the applica-tion of said second phase signal when enabled by the applica-tion of said zero density of non-use condition or by the ap-plication merely of said second phase signal, means which produce a timing signal each time said counting means is advanced a predetermined number of times, and timing means which energizes said ancillary replenish-ment pump for a predetermined time interval when said timing signal is applied to said timing means.