US1556845A - Photographic light-timing device - Google Patents

Photographic light-timing device Download PDF

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US1556845A
US1556845A US676982A US67698223A US1556845A US 1556845 A US1556845 A US 1556845A US 676982 A US676982 A US 676982A US 67698223 A US67698223 A US 67698223A US 1556845 A US1556845 A US 1556845A
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circuit
weight
drum
speed
light
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US676982A
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Alexander T Koppe
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DIRECTOPLATE Corp
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DIRECTOPLATE CORP
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    • GPHYSICS
    • G03PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03BAPPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00Photographic printing apparatus
    • G03B27/02Exposure apparatus for contact printing
    • G03B27/14Details
    • G03B27/16Illumination arrangements, e.g. positioning of lamps, positioning of reflectors

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  • a further object is to provide an automatic light timing device which controls a circuit maker and breaker and which device is weight operated and controlled through escapement mechanism as to its speed of operation, said escapement mechanism being controlled in its time of operation through' motor means in connection with a circuit in which circuit a photographic light isdisposed, and in which circuit the circuit maker and breaker is connected, thereby controlling the light timing device through mechanism driven through a motor, the speed of which varies with the voltage of the circuit, and
  • a further object is to provide an automatic light timing device comprising a rotatable drum having connected thereto a flexible member and a weight for rotating the drum in one direction, a-handle member having a pawl and carried by the drum, which pawl cooperates with a ratchet wheel, the rotation of which is controlled through a gear train connection with an escapment, wheel, the speed of operation of escapement wheel is controlledthrough the means of an electric motor, which motor is in circuit with a photographic lamp, and the speed of-operation controlled by the voltage of the circuit. Also to provide below the weight a normally closed circuit maker and breaker, which circuit maker and breaker is opened by the weight as it is lowered incident to the rotation of the drum.
  • a further object is to provide a scale having an adjustable stop with which the drum carried lever cooperates when moved in one direction whereby successive exposures of the same duration may be made.
  • the speed of operation of the device is controlled during successive operations for giving the same light values according to the fluctuation of-the voltage in the circuit which caries the photographic light.
  • Figure 1 is a front elevation of the device.
  • Figure 2 is a top plan view of the device.
  • Figure 3 is a rear view of the dial plate.
  • Figure ⁇ is a front elevation of the weight controlling mechanism showing the dial plate removed.
  • Figure 5 is avertical transverse sectional view taken on line 5-5 of Figure 4.
  • FIG. 6 is a rear view of the Weight controlling mechanism, showing the base plate base 1 by means of screws 3 is a casing 4, 1
  • a ratchet wheel 15 Secured to the shaft 9, preferably rearwardly of the drum 10 is a ratchet wheel 15, which wheel rotates with the shaft 9 and is engaged by a pawl 16, which pawl is drum 10 for restoring the handle member to.
  • said pawl.16 may bemoved out of cooperative engagement with the ratchet wheel 15, however if so desired the a spring 20.
  • a motor 23 is provided on the panel 1, which" motor is in circuit with the servicecircuit, which supples energy to the various motors operating whereby the elevators and motors of machinery in the printing plant, consequently the speed of operation of the motor 23 will vary. according to the fluctuations of the voltage on the circuit 22.
  • Motor 23 is provided with a 'worm- 24, which meshes with a worm. gear 25, carried by a vertically disposed shaft 26,
  • connecting rod 29 will reciprocate at various speeds according to the speed of operation of the motor 23, which motor will vary in speed of operation according to the voltage on the service line/ 22. 1
  • the other end of the connecting rod 29 is pivotally connected at 30 to a horizontally disposed:
  • lever 31 which lever is oscillated during the rotation of the disc 27 and consequently os-
  • Escapement wheel 34 controls the shaft 9 through a gear train composed of gears 35, 36,37 and. 38;
  • segmentally shaped scale 6,' which scale is arouate sha ed as shown in Figure 2 and has its rear .si e provided with an internal rack 40, on .whichis. slidably mounted an adjustable stop 41, with which rack the pivoted s ring actuated detent 42 cooperates. for ho ding the stop in any position to which it may be moved for positioning its pointer 43 in trat-ion with any of the time graduations 44 on, the scale 6.
  • the stop 41 is positioned its pointer 43, registers with the four minute exposure graduation, and that when the-handle member 18 is moved to the right until it is stopped by the stop memregisber 41, a four minute exposure adjustment mg t e same after a predetermined :-x--
  • r Slidably mounted in the lower end of tlre tubular member 14' is a weight engaging poses of illustration a generator 52 is provided .forgenerating current for the circuit.
  • the first plate is printed after setting the lever 18 at the desired graduation on the scale 6, and closing the switch 51. WVhen the switch 51 is closed, the motor 23 immediately starts to operate and consequently the escapement shaft 32 is oscillated, thereby allowing the gear train, the shaft 9, and the drum 10, through its connection with the ratchet wheel 15, to rotate under the infiuence'of the weight 13.
  • the voltage fluctuates in the circuit 22 the speed of rotation of the motor 23 is varied according to the voltage and consequently the speed of rotation of the drum and thedownward movement of the weight 13 will vary, and consequently the time of breaking of the circuit by the vdownward movement of the contact member 47 will vary, thereby allowing the same light values to be given in successive exposures.
  • the voltage of the arc light also fluctuates, consequently itwill be seen that uniformity of exposure of successive plates is obtained at all times with uni- 1 form light values.
  • the weight alone is the driving means for the mechanism controlling the circuitmaker and breaker, and that the motor 23 only serves to operate escapement mechanism at various speeds according to the fluctuation of the voltage.
  • the invention having been set forth what is claimed as new and useful is 1.
  • 2. The combination with a photographic light circuit, a light carried by said circuit, of-an automatically controlled weight mem ber, said weight member cooperating with a circuit maker and breaker, whereby successive operations of the circuit maker and breaker will vary in time incident to the fluctuation of the voltage of the circuit, thereby allowing successive exposures of uniform value.
  • a vertically movable weight a circuit maker and breaker with which said weight c0operates and opens upon the downward move-- ment of the weight, said weight being connected to a rotatable drum, a ratchet wheel a ratchet connection between said wheel and drum, escapement mechanism controlling the rotation of the ratchet Wheel against the weight, a motor carried by said circuit, and controlling 25 of the weight into contact with the depress-' 1 le member.
  • the combination wit h'a photographic light circuit controlled by a suspended weight cooperating with a circuit maker and breaker carried by said circuit, escapement mechanism for controlling the movement in one direction of the weight, and a motor carried by the circuit and controlling the" speed of operation of the escapement mechanism incident to the fluctuation of the voltage on the circuit.
  • ratchet wheel a ratchet connection between the drum and ratchet wheel, said weight circuit, a suspended vertically movforming means for rotating the drum in unison with the ratchet wheel, escapement mechanism controlling the speed of rotation of the ratchet wheel, a motor carried by'said circuit, said motor forming means for operating the escapement mechanism.

Description

Oct. 13, 1925.
A. T. KOPPE PHOTOGRAPHIC LIGHT TIMING DEVICE Filed Nov. 26, 1923 3 Sheets-Sheet 1 I N V EN TOR.
" fl/emzzder I y A TTORNEY.
Oct. 13, 1925.
A. T. KOPPE PHOTOGRAPHIC LIGHT TIMING DEVICE Filed Nov. 26 1923 3 Sheets-Sheet 2 I t I l I z I P I mu w h 1 I 4 m /j Z42 a 4% ..J A? 5AM -r I @g L a #81 if a 4! :1 E] 3 E I 1, 4
I r w 79 0'3:
\5 I; w l s 7 Z 1 Z -1 {2* j /j Z 2 Q o g @5 1 @5 O HAZE-5 o I? 4 k 2 /z 79% Z fl/elaizairf/fa ape INVENTOR.
ATTORNEY.
Oct. 13, 1925- 1,556,845 A. T. KOPPE PHOTOGRAPHIC LIGHT TIMING DEVICE Filed Nov. 26. 1923 3 Sheets-Sheet 3 fllezczrzderf Kappa INVENTOR.
BY I
A TT ORNE Y.
Patented Oct. 13, 1925.
UNITED STATES v 1,556,845 PATENT OFFICE,
ALEXANDER '1. KO'PPE, OF CHICAGO, ILLINOIS, ASSIGNOR T DIRECTOPLATE COB- POBATION, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.
PHOTOGRAPHIC LIGHT-TIMING DEVICE.
Application filed November26, 1923. Serial No. 676,982.
for making fi'set press plates, which plates are sensitized and the image photographically produced thereon. Where machines of this character are used, they are usually in stalled in large printing plants in which elevators, presses and other machines are elec- ,1
trically driven, consequently the voltage of the service line and circuits connected therewith vary inversely with the load, as thevarious machines are thrown into and out of operation. However to obtain unlformlty of Y exposure of successive prints made on a plate. or to obtain prints produced by suflicient time exposure, it is necessary to measure out the light in equal quantity for each successive exposure, ;..or until the required quantity of light'has been measured out to produce satisfactory results, therefore it is a primary object of the invention to provide an automatic light timing device, wherein the exposure is lengthened or shortened in time, automatically to compensate for the fall or rise in the voltage of the service line.
A further object is to provide an automatic light timing device which controls a circuit maker and breaker and which device is weight operated and controlled through escapement mechanism as to its speed of operation, said escapement mechanism being controlled in its time of operation through' motor means in connection with a circuit in which circuit a photographic light isdisposed, and in which circuit the circuit maker and breaker is connected, thereby controlling the light timing device through mechanism driven through a motor, the speed of which varies with the voltage of the circuit, and
/ consequently measuring out successive equal amounts of rays from the light upon variable periods of operation of the timing device during the fluctuation of the voltage.
A further object is to provide an automatic light timing device comprising a rotatable drum having connected thereto a flexible member and a weight for rotating the drum in one direction, a-handle member having a pawl and carried by the drum, which pawl cooperates with a ratchet wheel, the rotation of which is controlled through a gear train connection with an escapment, wheel, the speed of operation of escapement wheel is controlledthrough the means of an electric motor, which motor is in circuit with a photographic lamp, and the speed of-operation controlled by the voltage of the circuit. Also to provide below the weight a normally closed circuit maker and breaker, which circuit maker and breaker is opened by the weight as it is lowered incident to the rotation of the drum.
A further object is to provide a scale having an adjustable stop with which the drum carried lever cooperates when moved in one direction whereby successive exposures of the same duration may be made. However the speed of operation of the device is controlled during successive operations for giving the same light values according to the fluctuation of-the voltage in the circuit which caries the photographic light.
With the above. and other objects in view the invention resides in the combination and arrangement of parts as hereinafter set forth, shown in the drawings, described and claimed, it being understood that changes in the precise embodiment of the invention may be made within the scope of what is claimed without departing from the spirit of the invention.
In the drawings r v Figure 1 is a front elevation of the device. Figure 2 is a top plan view of the device. Figure 3 is a rear view of the dial plate. Figure {is a front elevation of the weight controlling mechanism showing the dial plate removed.
Figure 5 is avertical transverse sectional view taken on line 5-5 of Figure 4.
Figure 6 is a rear view of the Weight controlling mechanism, showing the base plate base 1 by means of screws 3 is a casing 4, 1
with the drum 10 which casing isprovided with a vcoverplate 5, which carries a segmentally shaped dial 6, and within the casing and. cover plate 5 the weight controlling mechanism is dis posed. Rotatably mounted in bearings 7 of the casin 4 and of the bracket 8 is a horizontally isposed shaft 9, onvwhich is rotatably mounted a drum 10, to which is secured at 11, a chain 12. During the operation of the device, during'a time exposure, the drum 10 rotates in the direction of the arrow a.
thereby unwinding the chain 12 under the influence of th weight 13, which is guided in a tubular member 14. The rotation of the drum '10 in the direction of the arrow it is entirely controlled by said weight 13 and the speed of rotation of the drum is regulated through mechanism hereinafter set forth. Secured to the shaft 9, preferably rearwardly of the drum 10 is a ratchet wheel 15, which wheel rotates with the shaft 9 and is engaged by a pawl 16, which pawl is drum 10 for restoring the handle member to.
initial position, said pawl.16 may bemoved out of cooperative engagement with the ratchet wheel 15, however if so desired the a spring 20.
wheel 10 may be restored by movement in the direction of the arrow 1) by grasping the handle and moving the same in the direction of the arrow b at whichtime the pawl 16 will ratchet over the teeth of 'the'ratchet wheel 15, against the action of the coiled It has been foundin making ofl'set press plates that it is necessary to expose the sensitized successive plates to light rays of uniform value. Under this condition it is obvious the periods of exposure of each plate must vary incident to the fluctuating voltage of the line on which the arc lamp 21 is connected, for instance the circuit 22, which may supply electric energy to elevators and va- IlOllS motors in the printing establishment,
which motors are thrown intoand out of operation at various times as well as the .elevator. It is obvious that under these condit'ions the voltage of the circuit 22 will fluctuate and consequently a period of time. nec essary for a proper ex sure of the sensitized plate would be su cient for one plate, and would not be suflicient for a succeeding plate. To obviate this'difliculty a motor 23 is provided on the panel 1, which" motor is in circuit with the servicecircuit, which supples energy to the various motors operating whereby the elevators and motors of machinery in the printing plant, consequently the speed of operation of the motor 23 will vary. according to the fluctuations of the voltage on the circuit 22. Motor 23 is provided with a 'worm- 24, which meshes with a worm. gear 25, carried by a vertically disposed shaft 26,
the upper end of which is provided with a disc 27, to which is pivotally connected at 28 a connecting rod 29. It will be seen that theconnecting rod 29 will reciprocate at various speeds according to the speed of operation of the motor 23, which motor will vary in speed of operation according to the voltage on the service line/ 22. 1 The other end of the connecting rod 29 is pivotally connected at 30 to a horizontally disposed:
lever 31, which lever is oscillated during the rotation of the disc 27 and consequently os-,
cillates the verticallydis d shaft 32.
Shaft 32'extends downw-ar ly into the casing 4 and is provided with spacedescapement lugs 33, which lugs are disposed at opposite sides of th escapement 34 and during the oscillation of the shaft 32 control the rotation of the escapement wheel, the speed of rotation being controlled by thespeedof oscillation of the shaft 32,.which is in turn controlled from the motor 23. Escapement wheel 34 controls the shaft 9 through a gear train composed of gears 35, 36,37 and. 38;
consequently the speed' of rotation of the shaft 9 and the ratchet wheel 15 is controlled.
by the speed of rotation of the escapement.
wheel 34; therefore the weight 13'can only unwind the chain 12 from the drum 10 at the speed the escapement. mechanism allows the ratchet wheel 15, which is connected to the'drum 10 by the pawl 16, "to rotate. s
Secured to the outer face of the cover plate 5 by means of screws 39 is the segmentally shaped scale 6,'which scale is arouate sha ed as shown in Figure 2 and has its rear .si e provided with an internal rack 40, on .whichis. slidably mounted an adjustable stop 41, with which rack the pivoted s ring actuated detent 42 cooperates. for ho ding the stop in any position to which it may be moved for positioning its pointer 43 in trat-ion with any of the time graduations 44 on, the scale 6. Referring to Figure 1 it will be seen that the stop 41 is positioned its pointer 43, registers with the four minute exposure graduation, and that when the-handle member 18 is moved to the right until it is stopped by the stop memregisber 41, a four minute exposure adjustment mg t e same after a predetermined :-x--
hting the arc lamp 21, and extinguish posure'pf the sensitized plate to the light 21 is obtained. r Slidably mounted in the lower end of tlre tubular member 14'is a weight engaging poses of illustration a generator 52 is provided .forgenerating current for the circuit.
V In operation the first plate is printed after setting the lever 18 at the desired graduation on the scale 6, and closing the switch 51. WVhen the switch 51 is closed, the motor 23 immediately starts to operate and consequently the escapement shaft 32 is oscillated, thereby allowing the gear train, the shaft 9, and the drum 10, through its connection with the ratchet wheel 15, to rotate under the infiuence'of the weight 13. If during the operation the voltage fluctuates in the circuit 22 the speed of rotation of the motor 23 is varied according to the voltage and consequently the speed of rotation of the drum and thedownward movement of the weight 13 will vary, and consequently the time of breaking of the circuit by the vdownward movement of the contact member 47 will vary, thereby allowing the same light values to be given in successive exposures. Dur-in the fluctuation of the voltageron the circuit 22, the voltage of the arc light also fluctuates, consequently itwill be seen that uniformity of exposure of successive plates is obtained at all times with uni- 1 form light values.
From the above it will be seen that an automatic light timing device 'is provided,
particularly adapted for use in connection with sensitized plates on which images are photographica-lly produced, aIRl that periods ofexposure for successive plates will be automatically obtained whereby equal light values will be given to successive platesincident to fluctuating voltage on the service circuit, by automatically varying the time of exposure. according to the load and fluc-.
tuating voltage of the service circuit. It will also be seen that the weight alone is the driving means for the mechanism controlling the circuitmaker and breaker, and that the motor 23 only serves to operate escapement mechanism at various speeds according to the fluctuation of the voltage.
, The invention having been set forth what is claimed as new and useful is 1. The combination with a photographic light circuit-,a light carried by said circuit, a circuit maker and breaker carried by said circuit, of an automatically controlled flexible member having its weight for opening said circuit maker and breaker, and means for controlling said weight in its speed of movement incident to the fluctuating voltage on'the circuit. 2. The combination with a photographic light circuit, a light carried by said circuit, of-an automatically controlled weight mem ber, said weight member cooperating with a circuit maker and breaker, whereby successive operations of the circuit maker and breaker will vary in time incident to the fluctuation of the voltage of the circuit, thereby allowing successive exposures of uniform value.
3. The combination with a photographic light circuit, a light carried bysaid circuit,
of an automatically controlled weight memment mechanism for allowing the movement of the weight into cooperative relation with the circuit maker and breaker, said escapement mechanism being controlled in its speed of operation by a motor in said cii'-' cuit.
5. The combination with a photographic light circuit, a light carried by said circuit, a circuit maker and breaker carried by said circuit, a vertically movable weight ceoperating with said circuit maker and breaker for breaking said circuit, escapeinent mechanism for controlling the downward movement of said weight, and a motor carried by said circuit and controlling the speed of operation of the escapement mechanism against the. action of the weight.
6. The combination with a photographic light circuit, a light'carried by said circuit, a circuit maker and breaker carried by said circuit, a vertical movable weight above said circuit maker and breaker and cooperating therewith, a rotatable drum, a. end extending over the drum and connected thereto, a shaft, a ratchet wheel carried by said shaft and rotatable therewith, a ratchet pawl connection between the drum and ratchet, escapemeni mechanism for controlling the speed of rota tion of the ratchet, said ratchet controlling the speed of rotation .of the drum against the action of the weight, a motor carried by said circuit, said motor controlling the speed of operation of the escapement mechanism.
7. The combination with a photographic light circuit, a light carried by said circuit,
light circuit, a light carried by said circuit, a p
; adjacent said drum,
a vertically movable weight, a circuit maker and breaker with which said weight c0operates and opens upon the downward move-- ment of the weight, said weight being connected to a rotatable drum, a ratchet wheel a ratchet connection between said wheel and drum, escapement mechanism controlling the rotation of the ratchet Wheel against the weight, a motor carried by said circuit, and controlling 25 of the weight into contact with the depress-' 1 le member.
9. The combination with a photographic light circuit, a light carried by said circuit, a circuit maker and breaker carried by said able weight cooperating with said circuit maker and breaker for opening the same upon a downward movement of the weight, escapement mechanism for controlling the speed of downward movement of the weight, and a motor carried by said circuit and controlling the speed of operation of the escapement mechanism. according to the fluctuation of voltage on the circuit.
10. The combination with a photographic light circuit controlled through a suspended Weight cooperating with a circuit maker and breaker carriedby said circuit, of means operated by a. motor carried by the circuit for varying the speed of movement of the weight'incident to the fluctuation of the voltage on the circuit. V
11, The combination wit h'a photographic light circuit controlled by a suspended weight cooperating with a circuit maker and breaker carried by said circuit, escapement mechanism for controlling the movement in one direction of the weight, and a motor carried by the circuit and controlling the" speed of operation of the escapement mechanism incident to the fluctuation of the voltage on the circuit.
12. The combination with a photographic light circuit controlled by a suspended weight cooperating with a circuit maker and breaker carried by the circuit, of means for I controlling the downward movement of said weight, said means comprising a rotatable drum on which the weight is suspended, a
ratchet wheel, a ratchet connection between the drum and ratchet wheel, said weight circuit, a suspended vertically movforming means for rotating the drum in unison with the ratchet wheel, escapement mechanism controlling the speed of rotation of the ratchet wheel, a motor carried by'said circuit, said motor forming means for operating the escapement mechanism.
13. The combination with. an electric circuit, a photographic light carried by said circuit, a depressible circuit maker and breaker carried by said circuit, of means for operating said circuit maker and breaker whereby successive light values will be obtained at various periods incident to the fluctuation of means comprising a vertically movable weight, a rotatable drum, a flexible member connected tocthe weight and extending over the drum connected thereto, a shaft extending through said drum, a ratchet wheel adjacent said drum, aratchet connection between the the ratchet wheel'and the drum whereby the speed of rotation of the drum will be controlled by the ratchet wheel, an escapement mechanism, a gear train connection between the escapement mechanism and the ratchet wheel,,a motor in said circuit, said motor controlling theoperation. of the voltage on the circuit, said escapement mechanism against the action of the weight. I 14. The combination with an electric circuit, a photographic light carried by said circuit, a circuit maker and breaker carried by said circuit, a suspended weight cooperating with said circuit maker and breaker, 00- operating ratchet and drum mechanism rotatable independent of each other in opposite directions and in unison in one direction, escapement mechanism controlling the rotation of the ratchet wheel when the ratchet wheel and drum are. rotated in the same direction, and motor driven mechanism in saidcircuit for controlling the speed of operation of the escapement mechanism.
15. The combination with a photo raphic light circuit having a fluctuating vo tage, a Weight controlled circuit maker and breaker carried by said circuit, of means operated by a motor in said circuit for varyin the speed of movement of the weight incigent to the fluctuation of the voltage on the circuit, thereby allowing successive exposures ofuniform valuelat varying periods of operation. 16. The combination with a light circuit, a light carried by.said circuit, a circuit maker and breaker carried by said circuit, timing means independent of said circuit and normally actuated at a uniform speed for opening said circuit maker and breaker at a predetermined time, and means carried by said circuit operating to control and vary the speed of movement of the circuit opening means and influenced in its own speed of movement by the fluctuation of the voltage. In testimony whereof I aflix my signature ALEXANDER T. KOPPE.
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