Process and apparatus for setting a reproduction camera

Claim 2

Process for setting the enlargement and focus of a reproduction camera having replaceable objective lenses which may have different focal lengths, said camera including a copy holder, an objective lens carrier and a carrier of the image plane, said carriers being individually movable to different distances from the copy holder and being driven by separate electric motors, which includes the steps of: a. determining separately the actual distances of the carriers from the copy holder by generating an electrical pulse at each incremental change in the distance of a carrier from the copy holder and adding or subtracting the successive pulses in a separate counter for each carrier in a digital computer according to the direction of change, b. introducing into the computer at least the values of the desired magnification and the focal length of the selected objective lens, c. computing digitally and separately for each carrier the desired distance of the carrier from the copy holder on the basis of at least the desired magnification and the focal length of the selected lens, d. comparing separately the determined actual distances with the corresponding desired computed distances, and e. controlling the motors in accordance with the results of the comparisons to turn each motor individually in the direction to decrease the difference between each actual and the corresponding desired distance, and to stop each motor when the comparison shows the corresponding difference to be null.

Claim 3

Process according to claim 1 wherein said electric pulses are generated at successive pole passages of the motor commutators relative to their brushes.

Claim 4

Process according to claim 1 wherein said electric motors are coupled to positioning means for said carriers and the process involves generating said electric pulses directly upon each incremental movement of the positioning means.

Claim 5

Process according to claim 1 wherein said carriers are movable relatively to a frame and the process involves generating said electric pulses directly upon each incremental movement of a carrier.

Claim 6

Process according to claim 1 wherein said carriers have starting positions at predetermined distances from the copy holder, which includes the steps of resetting each counter to a value corresponding to a predetermined distance when the corresponding carrier is at its starting position, and thereafter adding the electrical pulses to or subtracting them from the said reset values.

Claim 7

Process according to claim 1 wherein the desired distaNces from the copy holder to the objective lens carrier, a, and to the carrier of the image plane, (a + b), are computed in an electronic digital computer using the formulae: a f (1 + 1/m), and (a + b) f (1 + 1/m) + f (1 + m) by the steps which include: a generating the reciprocal 1/m, b. adding +1 to 1/m to obtain a'' (1 + 1/m), c multiplying a'' by f to obtain a f . a'', d adding +1 to m to obtain b'' (1 + m). e multiplying b'' by f to obtain b f . b'', and f adding a to b to obtain (a + b).

Claim 8

Process according to claim 6 which includes the steps of introducing into the computer the value of T and the value of HH'' for the selected lens, correcting the values of a and of (a + b) by adding algebraically the value of T to the former and the value of HH'' to the latter, and using the resulting corrected desired distances in the comparisons, T being the distance from the objective carrier to the principal of the lens and HH'' being the distance between the two nodal points of the lens.

Claim 9

In combination with the steps recited in claim 6: a. storing the computed desired distances and transmitting them to separate comparators, b. transmissing the determined actual distances to the corresponding comparators after each addition or subtraction of a pulse, and c. making said comparisons in said comparators.

Claim 10

A reproduction camera including a frame constructed to position a copy holder, a carrier for an objective lens, a carrier for the image plane, said carriers being independently movable relatively to the copy holder for altering their distances therefrom, separate electric motors having mechanical connections to the carriers for varying said distances, means for each carrier for generating an electrical pulse at each incremental change in one of said distances, and an electronic digital computer for setting the camera, comprising: a. a pair of counters connected by circuit means respectively to said pulse-generating means for adding or subtracting the pulses according to the directions of changes of said distances, thereby to determine the actual distances of the carriers from the copy holder, b. means for introducing the desired magnification m and the focal length f of the objective lens, c. computing means including at least one computing section for computing the desired distances of the carriers from the copy holder on the basis of at least the values of m and f, d. a comparator for each carrier, each comparator being connected to the counter of pulses for the respective carrier to receive the actual distance therefrom, and to the computing means to receive the desired distance for the respective carrier, said comparators being constructed to compare said actual and desired distances and having output circuit means which are energized to indicate which distance is greater or that the compared distances are equal, and e. a motor controller for each comparator connected to the output circuit means thereof and to the motor which drives the corresponding carrier, constructed to operate the respective motor in a direction to decrease the difference sensed in the comparator and to stop rotation of the motor when the comparison indicates that the distances are equal.

Claim 11

A reproduction camera including a frame constructed to position a copy holder, a carrier for an objective lens, a carrier for the image plane, said carriers being independently movable relatively to the copy holder for altering their distances therefrom, separate electric motors having mechanical connections to the carriers for varying said distances, means for each carrier for generating an electrical pulse at each incremental change in one of said distances, and an electronic digital computer for setting the camera, comprising: a. a pair of counters connected by circuit means respectively to said pulse-generating means for adding or subtracting the pulses according to the directions of changes of said distances, thereby to determine the actual distances of the carriers from the copy holder, b. means for introducing the desired magnification m and the focal length f of the objective lens, c. computing means including at least one computing section for computing the desired distances of the carriers from the copy holder on the basis of at least the values of m and f, d. a comparator for each carrier, each comparator being connected to the counter of pulses for the respective carrier to receive the actual distance therefrom, and to the computing means to receive the desired distance for the respective carrier, said comparators being constructed to compare said actual and desired distances and having output circuit means which are energized to indicate which distance is greater or that the compared distances are equal, and e. a motor controller for each comparator connected to the output circuit means thereof and to the motor which drives the corresponding carrier, constructed to operate the respective motor in a direction to decrease the difference sensed in the comparator and to stop rotation of the motor when the comparison indicates that the distances are equal.

Claim 12

A reproduction camera according to claim 9 which includes means for signalling when the positions of the carriers are at starting positions which are at predetermined distances from the copy holder, and means for each counter responsive to the corresponding one of said signals for resetting each counter individually to the respective predetermined distance when a signaL is emitted, whereby subsequent electrical pulses are added to or subtracted from the count to which the counter has been reset.

Claim 13

A reproduction camera according to claim 9 which includes electronic means for each counter connected to the output circuit means of the corresponding comparator for causing each pulse to be either added to or subtracted from the corresponding counter in accordance with the results of the comparison.

Claim 14

A reproduction camera according to claim 9 wherein said computer includes: a. means for introducing the value of T and the value of HH'', b. a unit for generating the reciprocal of m, c. four adding units, respectively for adding +1 to the reciprocal of m, for adding +1 to m, for adding the value of T to the product of (1 + 1/m) and f, and for adding together the said product, the value of HH'' and the product of (1 + m) and f, d. two multiplying units for generating, respectively, the two aforesaid products, and e. storage units for storing the computed quantities resulting from the third and fourth additions, T being the distance of the objective lens from the objective carrier and HH'' the distance between the nodal points of the lens.

Claim 15

A reproduction camera according to claim 9 which includes: a. an ''''and'''' gate connected to parts of the output circuit means of both comparators which parts are energized when the comparators indicate equalities between the compared distances, said gate having an output circuit, whereby said output circuit is energized only when both comparators indicate equalities, and b. visible means for indicating when said output circuit is energized.

Claim 16

A reproduction camera according to claim 13 wherein the camera includes a register for receiving the value of m, the desired magnification, and said visible indicating means includes an indicator connected to the said output circuit of the gate and to the said register and contains: a. means for displaying visible the value of m, and b. an interruptor connected in a power circuit for normally causing said display to be flashing, and means responsive to a signal in said output circuit for disabling the interruptor and presenting, thereby, a steady display of the value m when said output circuit is energized.

Claim 17

A reproduction camera according to claim 13 in which said computing means includes a unit for generating the reciprocal 1/m, said camera having an illumination controller which is connected both to said output circuit from the gate and to the output of said unit, said illumination controller being an electronic digital computer having the functions of: a. computing the degree of illumination as a function which includes 1/m as an argument, and b. permitting illumination of the copy only when said output circuit is energized.

Claim 18

A reproduction camera according to claim 9 wherein said pulse-generating means include resistances connected in series with the power circuits from the motor controllers to the motors, the motors having several poles, commutators and brushes, for varying the potentials across said resistors upon each pole passage, and each resistor is connected to a corresponding counter through a converter which produces pulses of suitable durations and amplitudes and are connected to sense the potentials across said resistors.

Claim 19

A reproduction camera according to claim 9 which includes: a. a positioning shaft for each carrier, drivenly coupled to the respective motors for positioning the carriers, b. elements rotatable with said shafts and having indicia thereon, and c. sensing devices for generating electrical pulses upon passage relatively thereto of said rotatable elements, said sensing devices constituting the said pulse-generating means.

Claim 20

A reproduction camera according to claim 9 which includes: a. scale graduations on a rigid member extending in the direction of movement of the carriers, and b. sensing devices for generating electrical pulses upon passage relatively thereto of said graduations, said sensing devices constituting the said pulse-generating means, c. the said rigid member or the sensing devices being on the frame and the other being first to the two carriers, respectively.

Claim 21

A reproduction camera according to claim 9 wherein the means for introducing the value of m includes an input device which is manually set, and the means for introducing f includes: a. a holder for receiving a card bearing, in machine readable indicia, the value of f, and b. circuit means for transmitting the value of f from the card to the computing means.

Claim 22

A reproduction camera according to claim 19 wherein said card bears, additionally and also in machine-readable indicia, the values of T and HH'', T being the distance from the objective carrier to the objective lens and HH'' the distance between the two nodal points of the lens, and the computer includes circuit means for transmitting the values of T and HH'' from the card to the computing means.

Claim 23

A reproduction camera according to claim 20 which includes a plurality of said card holders, and switch means for selectively energizing the circuit means leading to one of the card holders for transmitting to the computer means only the data from the card in the selected holder.