US1138963A

US1138963A - Means for printing an enlargement from a negative-film.

Info

Publication number: US1138963A
Application number: US82012114A
Authority: US
Inventors: Homer E Leash
Original assignee: JOHN L SCHWENK
Current assignee: JOHN L SCHWENK
Priority date: 1914-02-21
Filing date: 1914-02-21
Publication date: 1915-05-11
Anticipated expiration: 1932-05-11

Description

H. E. LEASH & I. L. SCHWENK.

MEANS FOR PRINTING AN ENLARGEMENT FROM A NEGATIVE FILM.

APPLICATION FILED FEB. 21, 1914.

1,138,963. Patented May11,1915.

. D STATES PATENT OFFICE.

HOIVIER E. LEASH AND JOHN L. SCHWEN K, 0]! NEW WESTMINSTER, BRITISH COLUMBIA, CANADA; SAID LEASH ASSIGNOR 'I'O SAID SCHWENK.

' MEANS FOR PRINTING AN ENLARGEMENT FROM A NEGATIVE-FILIVL,

- Specification of Letters Patent,

Patented May 11, 19115.

Application filed February 21, 1914. Serial No. 820,121.

To all whom it may concern Be it known that we, HOMER E. LEAsH and- JOHN L. S HWENK, ,citizens of the Dominion of Canada and of the United States of America, respectively, residing at New Westminster, in the Province of British Columbia, Canada, have invented certain new and useful Improvements in Means for Printing an Enlargement from a Negative- Film, of which the following is a specification.

This invention'relates to a device for photographicallyprinting an enlargement from anegative of a panoramic view, such as is taken by a Cirkut camera. views of these negatives are printed by contact exposure, and-when an enlargement is required, owing to the extreme length of the picture, it can only be done in sections.

The result thereby attained is seldom .satis-' factory, not only because of the unavoidable line at the junction 'of each section but because of the difiiculty in exactly matching the sectionsat the junction, both in location and tone.

The invention, which is the subject of this application has been devised to obtain a sat- .isfactory enlargement by moving the negative film across a plate having a cross slit through which the printing light is admitted, the representation of the picture At present,

printed is wound and the end of it is car- 'ried across the plate 3 and connected to the film receiving roller 5, which has provision for rotatingit, a friction'device being provided on the roller 4 to impose resistance to [its movement sufficient to -maintain the film tightly drawn across the plate 3. The frictional check may conveniently take the form of a dished resilient washer 16, as

" shown in Fig.- 3. Secured to and projecting of the middle line to the film reel 4, the

printing paper 21 is wound and its end is carried across a plate 10 and attached to the roller 9. These printing rollers 8 and Q-are of a width and diameter correspond-- ing to the desired enlargement and the roller 9 is driven at the same speed of rotation as shaft 11 on which worms 12 and 13 are sewhere it passes the slit being enlarged by passing it through a lens on to a printing paper of. the required size, which paper travels in the opposite directionat a speed proportioned to the ratio of the required enlargement, the negative film and the printing paper being moved simultaneously by a mechanism provided. The particular means by which this result may be carried into effect is fully set forth in the,follow-; ing specification, reference being made to the drawings by which it is accompanied,

in which:

Figure 1 is a vertical longitudinal section on the line 1 1 of Fig. 2, Fig. 2, a horizontal section on 'the line 2-2 in Fig. 1, and

Fig. 3, an enlarged detail of a check for the rollers.

Rotatably mounted at one end of a suitable frame 2 are'film rollers 4 and 5, one

rictional on each side of a plate 3 having a slit 6 extending across the width of the film. On

one of these rollers 4 the film 20 to be the negative film receiving roller 5 by a cured, l2 meshing with the teeth of a worm wheel 14 secured to'the film receiving roller 5 and 13 meshing with a worm wheel 15 secured on the print receiving reel 9.

To enable the shaft 11 to be rotated at a regular and slow rate, of speed by handand to facilitate variation of that speed to suit different printing papers the shaft 11 may be rotated by a worm gear (similar to that which is used for rotating the reels 5 and 9) from across shaft 17 rotatable in bearings in the base frame of the device, and provided with a small crank handle 18.

- The device may be arranged to give any desired ratio of enlargement by proportioning the distance from the lens to the printing'paper 21 in relation to the distance from the slit to the lens, that it shall be the same ratio that the diameter and width of the rollers 8 and 9 bear to those of the negative film rollers 4 and 5. v

The rollers 8 and 9 may be made of smaller size andbe driven at an increased speed. But the arrangement here set forth of using a diameter of roller of the required roportion and drivin it at the same speed is preferred, as the ifl'erent thlckness of the printing paper in relation to the thickness of the film is thereby conveniently provided for.

What We therefore claim and desire to be protected in by Letters Patent, is:

1. A device for photographically enlarging a picture from a negative film, said device comprising the combination With a suitable supporting frame, of a plate at one end. having a light admitting slit, a lens intermediate of the ends of the framein axial alinement with the slit, a roller rotatably mounted on one side of the slit plate on which roller the negative film, is Wound, a filmreceiving roller rotatably mounted on the other side of the slit to which roller the film is connected across the slit plate from the other roller, a plate at the other end of the frame at the required distance from the lens to give the desired enlargement of the picture, a roller mounted on one side of this plate on which roller a strip of printing paper is Wound, a roller rotatably mounted on the other side of this plate to which roller the strip of printing paper is connected across the plate from the other roller the diameter of the print receivin roller being roportioned to that ofthe film receiving roller in the ratio of the desired enlargement, and means for simultaneously menace rotating the two receiving rollers at a uni,

form-speed.

2. A device for photographically enlarging a picture from a negative film, said device comprising the combination with a suitable supporting frame, of a plate having a light admitting slit, a roller having a film. wound on it, said roller rotatably mounted on one side of the slit plate, a film receiving roller rotatably mounted on the other side of the slit plate to Which roller the end of the film is attached across the plate, a lens the axis of which is in alinement with the slit, a plate normal to the axis of the lens at the required distance from it to give the desired enlargement, a roller on which a strip .of photographic printing paper is wound, Which roller is rotatably mounted on one side of the plate, a print receiving roller rotatably mounted on the other side, of the plate to which roller the printing paper from the other roller is attached across the plate, means preventing free rotation or the roller on which the film is initially coiled, means preventing free rotation ofthe roller on Which the printing paper is initially wound, and means for simultaneously rotating the film receiving reel and the print re ceiving reel.

lln testimony whereof we affix our signatures in presence of two Witnesses.

HGMER E. LEASE. JOHN L. SCHVVENK.

Witnesses:

ROWLAND lBmr'rArN, I lVilAY Wnr'rn.