US994475A

US994475A - Photographic-printing apparatus.

Info

Publication number: US994475A
Application number: US59707810A
Authority: US
Inventors: Alexander D Mccurdy
Original assignee: Individual
Current assignee: Individual
Priority date: 1910-12-13
Filing date: 1910-12-13
Publication date: 1911-06-06
Anticipated expiration: 1928-06-06

Description

A. D. MoOURDY.

PHOTOGRAPHIO PRINTING APPARATUS. APPLIUATION 111.211 13110.13, 1910.

994,475. Patented June 6,1911.

9 SHEETS-SHEET 1.

A. D. IVIOGURDY.

v PHOTOGRAPHIG PRINTING APPARATUS. APPLICATION FILED DEG-13, 1910.

994,475, r Patented June 6, 1911.

9 SHEETS-SHBBT'Z.

V A. n. MoOURDY. PHOTOGRAPHIG PRINTING APPARATUS.

APPLICATION I'ILEI) DEO- 13, 1910.

Patented June 6, 1911.

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A; D. 'MOGURDY.

PHOTOGBAPHIG PRINTING APPARATUS;

APPLICATION FILED DE0 13, 1910.

Patented June 6,1911.

9 sums-sum A. n. MoGURDY. PHQTOGRAPHIG PRINTING APPARATUS.

APPLIOATIOI FILED DEG-13, 1910. 994,475. Patented June 6, 1911.

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A. D. MOGURDY. PHOTOGBAPHIG PRINTING APPARATUS.

APPLICATION FILED D170. 13, 1910. 994,475. 1 Patented June 6,1911.

9 SHEETS-SHEET '7.

A. n. MoGURDY. PHOTOGRAPHIO PRINTING APPARATUS.

APPLIOATIOI rum) md. 13, 1910.

A. 1).. MGOURDY.

PHOTOGRAPHIG PBiNTING APPARATUS.

# APPLIUATION FILED DBD.13, 1910..

994,475, Patented June 6,1911.

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i ALEXANDER ID. MGCURDY, 0F PHILADELPHIA, ,ZI RENNSY'LVAINIA,v

Specification 62 Letters Patent.

PIHOTOGRAPHICFPRINTING' APPARATHS. I

Patented. -June. 6, di it;

, Application filedDec'e'mber 13, 1910. Serial its. 59?,078.

To all whom it-may concern:

Be it .known that I, ALEXANDER D. Mo- CURDY, a citizen of the-United States, residing in Philadelphia, Pennsylvania, have invented certain Improvements in Photographic-Printing. Apparatus, of which the following is a s ecification. I

One-object o my invention is to provide aimachine for making positive prints from photographic negatives, which may be quickly and conveniently adjusted to cause it to give what are practically perfectly uniform. rints even though-the paper used, the intensity of the source of illumination and the negatives may vary widely asto their -qualities.

Another object-of the invention is to pro vide a photographic printing machine with means whereby the time of exposure may be adjusted to the intensity of the light pass. ing from a given source through a-negative to a sensitized paperfor other surface so as to produce prints of a predetermined density even though the negatlves, may vary widely as to their density and the paper in use may.

. likewise differ as to its sensitiveness.

I alsodesire. to provide aphotographic printing machine having the above characprinting machine which, after being adj-usted to permitlight from a source'to pass I through a negative onto a sensitized surface,

may be put in operation to cause said surface to be exposed for apredetennined time to the action of the light; the invention also contemplating novel-devices for making the various adjustments rendered necessary by" variations-in the light, in the density of the. negatives, and in the character of the paper employed, which devicesare relatively simple both as to their construction and modeof operation. I I

A still further object of theinvention is to provide a photograpic printing machine whereby enlargements maybe made from a given negative from a source of light and in which, the time of exposure to such light may be adjusted to meet the varying conditions arising from-the different gradesofpapers or other sensitized bodies which it is desired to print, from variations in the negative .or in the light itself.

These objects and otheradvantageous' ends I secure as hereinafter set forth, reference bein had to the accompanying drawings, in whic Figure 1, is a perspective view of my photographic printing machine; 2;, is 'a vertical section of the machine shown in'-- detail construction and'ai'rangement -o certain parts of-the shutter actuating means; Figs. 10 and. 11 are two detached perspective views'of two oi the shutter controlling pins;

Fig. 12, is'aadetached perspective View.

further illustrating the construction of the shutter and its associated parts; Fi s. 14, 15

5 and; 6; Fig. 13, is a perspective'vi' w of the shutter and its associated-parts Figs; 14,15 and 16 are elevations illustrating different positions of the shutter parts under operating conditions; Figs.'17,--18, 19 and= 20 are diagrammatic views illustrating jthe difie'rent positions occupied. by: certain parts of the shutter actuating mechanism under. operating conditions; Fig. 21 is a front elevation of the testplate forming part of my invention; Figs. 22 and 23 are plans of two of thescales used in adjusting my machine and forming part thereof; Fig. 23 is an elevation of two ofthe adjusting-wheels and their associated disks or. scales. Fig. 24-is a side elevation, partly. in longitudinal section, illustrating my invention used in connection withan enlarging camera; Fig. 25 is a vertical section on the line (Z-Z,Fig. 24: show ing v the relative arrangement of the said camera and the printing machine when this latter is packed inside of the camera for purposes of transportation, and Fig. 26 is a side elevation illustrating-a modified form ofmy invention.

Inthe above drawings, '1 is a somewhat elongated boxpreferably of rectangular section, onone end ofswhich is-mounted a lamp 2 serving-as the source of 1" ht for the machine, and which has its enii h opposite the lamp closed by a door 39 hinged adjacent to its lower edge to permit of its being opened for a purpose hereafter noted. At the top of the box is an observation opening 4 covered with a plate of glass 5 (which may under certain conditions be red or orange colored) and preferably having a projecting eye-piece 6. In the top of the box isa-n opening for the introduction of a slide or holder 7 designed to carry either a test plate ture by a rod 10, said mantle being suppliedwith gas through a pipe 11 and a burner 12. The rear end 13 of the lamp casing 2 is preferably made removable and carries a refiector l l of metal or glass, although preferably this element consists of a highly polished body of aluminum. The reflector is preferably concave in form and its polished surface is protected from the tarnishing effect of the heat from the mantle by a glass cover 15. In one side of the lamp there is preferably an opening closed by plates 16 and 17 of orange and ruby glass or other bodies of material, incapable, of transmitting actinic rays of light, so that withthis construction the lamp may be used for ordinary photographic work. I

The lamp casing is provided with a chimney 18 having at its upper portion a pair of concentric

cylindrical deflectors

19 and 20, between which is placed an inverted conical deflector 21.- The inner cylinder 20 as well as this deflector has openings for the escape of the heated roducts of combustion from the lamp, an there is a suitable cover 22 mounted on these parts ;the deflector 19 having a series of openings in its upper part immediately adjacent said cover, and the various parts with their openings being so arran ed as to provide for the escape of gases rom the lamp while effectually preventing any possible. leakage of light.

In order to insure that the operator shall not be burned by accidental contact with the heatedcover 22, I provide the rod 10 with an extension beyond said cover and fix to it a metallic plate 23 carrying a sheet of asbestos 2 1and a plate or other cover 25 of wood or other suitable non-conductor of heat.

The interior of the box 1 may. be considered as divided into three compartments, of which that adjacent the lens 8 contains the shutter operatingand adjusting mecha-- nism as well as an auxiliary shutter; this compartment being divided from the middle compartment by a vertical partition 26.

There is in this partition a circular opening, whose center is in the horizontal axis of the lens 8 and which is covered with a sheet 27 of clear glass. A. frusto-conical tube 28 is mounted between the partition 26 and the end 29 of the box in such position that its axis is co-incident with the axis of the lens so that there-is no danger of escape of light nor possibility of dirt or foreign bodies getting into the shutter. In the upper part of the first compartment is mounted a plane reflector or mirror 30 in such position that it extends through an opening in the parti tion 26 into the middle compartment of the box and is set at such an angle that rays of light emitted from the source 9, passing through an opening in the end 29 of the box, are reflected in substantia ly horizontal lines on to a second mirror 31, hereafter referred to and mounted in the third compartment of the box 1. The opening in the front end 29 of the box is covered or closed by a plate of clear glass as indicated at 32 to prevent entrance of products of combustion. The second and third compartments are divided from each other by a double partition whose two parts 33 and 34 are spaced apart by a distance equal to the thickness of the negative holder or printing frame 7, and there is in each of them a relatively large and usually rectangular opening practically the size of the negatives to be printed from and having its center in line with the optical center of the lens 8. A tube 35 extendsbetween the partition 26 and the part 33 of the second partition, having its axis practically co-incident with a straight line joining the centers of the two mirrors 30 and 31; there being openings in the parts 33 and 34 of the double partition to permit of the unobstructed passage of the light between these two mirrors. There is also a tube 36 mounted in the negative holder or printing frame, which, when this latter is in its proper position, is in line with the two openings. In the third compartment is mounted a mirror 37 having a generally trapezoidal shape and hinged on a horizontally placed spindle 38 mounted in the lower portion of the partition 34 immediately below the large opening thereof. Under normal conditions this mirror lies at an angle of about 45 to the horizontal; its upper end resting against a door 39 in the back end 3 of the box,1. The spindle 38 extends through one side of the box and its end is provided with a knurled head or hand wheel 40 whereby the mirror --may be moved when the enlarging attachment has been used, as hereafter noted. The door 39 is hinged at its lower edge to the end piece 3 of the box 1 and has fixed to its inner face a hook or catch 41 of sheet material designed to engage the upper edge of the mirror 37 so as to prevent this moving as long as the door is closed. Between the 55 54 Whose end engages and serves as one of enema door 39 and theeountersunk portion of the end 3 .in which it is mounted, I preferably place a gasket or washer--42 of some soft material such as felt in order to prevent 5 pos'sibleleakage of light. In the upper part of the door is mounted an angular shaped piece 43 of sheet material whose free end we tends into a recess in the end?) of the box.

intensity of the light by which the printing is;done, and; it is obvious that if practically uniform results are to be secured regardless of these variable factors, means must beprovided' for varying the length of time during which the printing is continued. In other words, practically uniform prints can be obtained with papers of widely different sensitiveness, usin I densities and with sources of light of various specific. intensities, merely by. increasing. or-decreasing the time of, exposure of the paper and for the purpose of determin-- ing and adjusting this time ofprinting to suit the varying conditions above noted, I v provide the particular mechanism shown in detail in Figs. 3 and 5 to 20 inclusive.

Immediately to the rear of the lens 8 and in front of the frusto-gonical tube 28,. I mount a two part shutter 45- whose con-- struction is clearly shown in Fig. 13. Said shutter consists of two flat plates or leaves 46 and so mounted as to overlap each other and supported by conical pivots 48 and 49 mounted in bearingmpreferably con structed as illustrated in Fig. '9. For the purpose of forming a supporting structure for the shutter and its associated parts I mount on the. inside surface of the ,box end 29 a thin metal plate 50, having an 'opening into whichfits the small end ofthetubular structure 28 and which carries two small brackets or

castings

51 and 52 for directly.

supporting the two shutter leaves. The

"first of these brackets has a short bearing screw 53 which engages'the pivot spindle 48 of the shutter leaf 6, while the bracket 52 serves to support a somewhat larger screwthe bearings for the conical pivot 49 of the shutter leaf 47. Both of the shutter leaves may bedescribed as consisting of crescent horns or ends thereof and it is-noted that the shutter leaf 46 has "an

opening

5,5;adja cent the middleof its concave edge preferably of rectangular. outline and covered by a plate of' yellow glass. Likewise the shutnegatives of different ter leaf 47 has an opening 56 which, under certain conditions may be caused tooverlap the opening in the leaf 46 to a greater or less extent so as to permit of the passage of more or less light through the shutter; This leaf 46 has fixed to its extension a short post 57 extending at right angles to its. general plane and formed adjacent its outer end to constitute an angular knife edge bearing 58; its extremity being cut away to form a fiat bearing'surface 59 for a purpose hereafter noted. 1

Fixedto the shutter leaf 47 is a projecting arm'60 having fixed to it a post 61 for the attachment of a'spring 62 and .also'having a. second post 63 for tripping a spring here'- fafter described;- there being a braking spring 63" mounted on the plate 50 for slowing down the movement of the shutter parts.

.The shutter. leaf 47 is slotted for the passage of the post 57 and the slot is. so'placedthat a ,force exerted laterally on said post will simultaneously swingboth shutter leaves on their pivots so that their concave edges ap-,.

proach or recede from each other. The

spring 62 acting through the post 61 and' arm 60 normally holds the shutter leaves (closed or tends to close them; it being under stood that the shutter is in its closed position' ,When said leaves overlap each other,

While the opening 56.may or maynot be in line with thenglass covered opening 55 For opening the shutter at will and thereafter closing it at the end of ap'redeterm'ned time, I provide some form of timecontro led' mechanism which may be set byhand and at the same time caused .to open the shutter;

pose I provide a longitudinally movable bar 64 projecting above the top surface'of the 'box- 1' at the end thereof adjacent the lamp 2 and extending Within-the compartment- 1 parallel to one edgeof the plate 50; the head "the time elapsing before the shutter isv closed of this bar being turned over to permit of its convenient manipulation. Thesaid plate- '50 is provided with a vertically extending slot 65 for the reception of aheaded pin 66 carried by the lower end ofthe bar 64, which on a post 68 projecting from one arm of the shutteropening lever 69. The pawl 67 has 2 'Whose opposite end is connected to 'a bracket 73 or to any other convenient point of att-achment. Saidpring-actsto oppose to return it to its upper position after it has been moved therefrom. Upon the plate 50.is

pin serves as a pivot for a pawl 67 operative.

. downward movement f the bar 64 and tends rying the pin 68, while its-long arm is extended adjacent a segmental guide 75 rigidly fixed to the upper portion of the plate 50 as shown in Figs. 3, 5 and 6. The upper end of this long arm of the lever is forked or branched so as to extend on opposite sides of this guiding segment and is normally maintained at the end of the segment dis" tant from that adjacent the bar 64 by means of a spring 76 having one end' connected to thebracket 73 andthe other to the short arm of said lever; there being a braking spring 69 mounted on the guiding segment for slowing down themovement'of the lever. Also mounted on the screw 54 is a timing lever 77 which, like the lever 69, is provided with a fork or branch at the end of its long arm whereby it is guided upon the segment 75. This lever has what is in effect a single short arm whose outer end is in the form of a toothed segment 78 curved concentrically with the pivot screw 54 and meshing with a pinion 79 3) carried on a spindle 80. This timing lever normally tends to move toward the end of the guide segment 75 dist-ant from the bar 64, under the action of a spring 81 extending .between its toothed arm and the bracket 73 heretofore referred to and is so mounted as to be engaged and turned on its pivot by the shutter openinglever 69 under certain conditions of operation. I

The spindle 80 has loosely mounted on it a gear wheel 82 and has keyed .to it a cylindrical drum 83 fixed to the pinion 7 9. The gear wheel carries a pair of dogs or pawls 84 so mounted as to acton the cylindrical surface of the ldrum' 83 (which may be toothed if desired) so as to couple it with the pinion 79 to said gear wheel when said drum tends to turn in one direction, although said dogs are so placed that they do not operatively connect said drum and gear wheel when the drum turns in the opposite direction; there being springs 85 on the gear 1 wheel pressing said dogs into engagement with the drum. Said gear wheel meshes with a pinion .86 fixed to an escapement wheel 87 and any suitable and desired form of escapement mechanism may be employed to regulate the operation of this escapement wheel and the mechanism connected thereto, under the action of the spring 81 trans"- mitted through the toothed arm 78 of the time lever 77 the pinion 79, drum 83, gear stopping on what may be termed a dead.

center, I provide a spring 91 supported at 1 wheel 82, and pinion 86. In the present inone end on the plate 50 and normally extended into engagement with one arm of said escapement lever so as to hold it in one of its extreme positions. When, however, the device is put into operation, the, post 63 which is carried by the arm 60 of the shutter-leaf 47 raisessaid spring out of engagement with the escapement lever, thereby permitting the latter to operate in the well known manrfen The pivot screw 54 in addition to supporting the levers hitherto referred to, also serves as a pivot or fulcrum for a lever 92 in which is formed an elon-- gated radial slot 93 and which has its outer end turned over and pointed to form an indicator 94 designed to coiiperate with a scale 95. on a suitably curved portion 96 of the segmental guide piece 75. This lever .92

has pivoted or ful'crumed to it bymeans of its spring 81. The short arm 98 .of the trip lever is extended .in the general line of the long arm thereof so as to be capable of engagement with a pin 99, Figs. 6 and 12, carried by a bell crank lever l00 fulcrumed on the shutter closin lever 69 by a screw 19 and normally held in a definite position by means of a spring 100 carried by the shutter closing lever 69. The second arm of this bell crank lev er carries a projecting pinor post 101' having a flattened surface, (Fig. 11) so placed as to cotiperate with the flattened portion 59 of the post 57 which projects from the shutter leaf 46. 1

' For manipulating the shutter leaves in order to determine the time of exposure to.

be given any particular negative, I provide a hand wheel 102 fixed to a spindle 103 extending into the interior, of the box 1, and having a suitable portion whereby it is prop erly carried in a bearing formed'in the end 29 of said box. Fixed to the spindle is a pinion 104 meshing with a toothed segment 105 preferably formed as part of a winking lever 106. This latter is pivoted or fulcrumed on a pm 107 mounted in-the plate 50 and in addition to having an elongated radial slot 108, has a recessed edge portion 109 provided with a number of projections whose outer portions 118 011 a curve eccentric to the pivot 107; the bottoms of the recesses between said projections preferably all lying on a circular curve concentric with said by the shutter leaf 46 so that as thelever .106 is turned on its pivot, the said post is alternately pushed away from the pivot 107 and then allowed to swing toward it; it being noted, however, that the amountv of v the middle compartment of the box 1, whichv ings in the 'end 29 of the machine adjacent movement imparted tdthe .post will vary from oneeend ot the part 109 to the other. Since as heretofore described, the post 57 extends through the shutter leaf 47, this reciprocating movement of the said post causes both shutter leaves to be simultaneously swung in opposite directions and the parts'are so arranged that when the smallest of the projections on the part 109 of the lever 106rengages the posh-the two shutter leaves are' moved 'apart a short distance so that the two openings 55' and 56am caused to overlap at two of their adjacent corners for a relatively 'small'amount, thus providing a small; opening for the passage of light from the lamp 2 into-the body of the box 1. As the post 57 is engaged 'by successively larger ones of the projections lying atgreater distances from the pivot pin'107, the shutter leaves are moved apart or swung on their pivots away from each other through successively'greater arcs; being allowed to return to their completely closed positions after each swing. Each time they [move apart, successively greater areas of their openings 55 and 56 overlap so that increasing amounts oflight are admitted to lighthowevenis non-ac t-inic because 0f th colored glass covering the'opening 55. The

swing of the winking lever 106, in addition to' causing alternate admission of'ligh't to and its cutting of? from themiddle compart ment 'ofthe machine, is designed to assist in" the'adjustm'ent of the indicator lever 92 and for this purpose I mount in the slot 108 a block'110 forming par't of a cross head-consisting of two blocks 111 and 112 besides the block llO'and having a screw113 whereby said'blocks are'movably held together. The

block 112 is slidable in the slot 93'of the indicator'lcver 92, while the block 111 has an opening for the reception of an arm 114, projectingfrom a curved slot-ted link 115 provided with teeth 116 on its inner or concave edge. In the slot of this link I mount a slid ing block 117 which is rigidly'fix'ed to the plate 50 so as to serve as a guidefor the link and its arm.

Meshing withthe teeth 116 of the link 115" is'a pinion 118- carried on a spindle 11.9 (Figs. 5 and 8) mountedin suitable bearthe lamp. This spindle extends through said end and has fixedto its outer portion a ha d' wheel whereby it, with the said pinion, may be turned at will. For preventing undue ease of movement of this hand.

122 so placed as to permit light from the I source 9 passing through the glass 32 to fall upon the mirror 30 and I providewan; auxili'ary shutter having two leaves 123 and 124 (Fig. 3) whereby this opening and hence the amount of light passing therethro'ugh may be varied within certain predetermined limits. These-two shutter leaves which vare of thin metal and overlap each other, are pivotally mounted on a pin or screw 125 so as to be free to swing toward and from each other in parallelplanes and have their adjacent edges notched or recessed. Each of these notches is in theform of a right angletriangle and theytogether form a rectangular opening whose area depends upon the rela; tive position of the two shutterleaves; that is to say, when said leaves overlap to their maximum extent there is no opening whatsoever and as'theyswing apart, there is a,

rectangular aperture through them whose area increases as the leaves are further separated, For thepurpose of operating the leaves 124: and123, so that as the lever 126 is moved with its pivotspindle 1'27,'said shutter leaves are drawn together or separated as the case may be. Under normal conditions they tend toapproach each other. under'the action of a spring 132 connecting them as shown.

.Mouritedgon the outer face of the end 29 of the machine is a graduatedscale 1 33 placed to cotiperate with the upper end of the lever 126 and arbitrarily graduated to correspond with the graduation on aplate 134 through which both of the

spindles

103 and 119 pass. As shown in Figsxl and 23 this plate is provided with a number of Shah low recesses or holes 185 designed'to receive a pin 136 .(Fig. 7 carried'by a spring arm 1'37 fixed to the spindle 103;the arrange- 'ment being such that when this pin is in such a position that it rests in one of the 1 holes 135, the edge 58 of the post 57 rests upon the top or end of one of the projections on'the edge 1'09 of the lever 106. The hand lever 126 is now moved over the scale 133 to a similarly numbered graduation of the scale 133, thereby adjusting the shutter leaves 123 and 124 in a predetermined manner.

For supporting the. negative and sensitized sheet or plate to be printed therefrom in the machine, I provide the negative holder or printing frame 7 which has a handle 138 whereby 1t may be manipulated. Said holder preferably consists of two rectangular frames 140 and 141 of sheet metal of angular section, hinged together at 139 and having openings through them slightly greater than the size of the paper and negatives to be used in the machine. The frame 141 has fastened to it a strip of wood or other suitable material 142 of such dimensions as to closely fit the opening in the top of the box 1 through which the holder is inserted and the handle 138 is fixed to this strip. The frame 140 carries a plate or pane of ground glass 143 mounted over its opening and held in position by any suitable means such as the metallic clips shown. Likewise the frame 141 has a plate or pane of clear glass 144 which, however, is so mounted as to permit of its relative movement toward and from the glass plate 143. For this purpose said plate 144- is provided with a metallic supporting frame 145 connected by springs 146 to the frame 141 so that while being at all times pressed toward the frame 140, it is free to move parallel to itself away from the same sufficiently to permit of the introduction of a celluloid or glass negative together with a sensitized glass or paper sheet to be printed. The springs 146 serve to press both the sensitized sheet and the negative closely together as well as removably hold them in the position between the two glass plates 143 and 144 and to press the two frames 140 and 141 into close contact is opaque. I preferably so construct the box with the frames or parts 33 and 34 so as to prevent leakage of light. As before indi-' cated there is a tube 136 mounted in the printing frame which is preferably fixed to the part 140 thereofand designed to extend loosely through the frame 141 so as to have its center line substantially coincident with the line joining the centers of the two mirrors 30 and 31.

For the preliminary adjustment of the machine I provide a, test plate shown in Fig. 21 which consists of a rectangular piece of glass rendered opaque except for a small rectangular central portion" 150. This is gray in color and has in, its central portion a cross or other shaped figure 151, which like the outer or main portion of the plate,

1 as to provide a cavity or container 152 for the reception. of this test plate when it is not in use.

It .is to be understood that before being actually used the machine constructed according to my invention must be calibrated and its various parts are so proportioned as to properly perform their functions. Nor-- mally the shutter leaves 46 and 47 are held in such position that they not only close the main opening through the lens 8 but also maintain the openings 55 and 56 out of line with each other.

In order to use the machine the lamp is lighted and it then becomes necessary to ascertain the itensity of the light emitted which depends chiefly on the condition of the mantle, the temperature of the burner, and the composition and pressure of the gas being used. For this purpose the negative holder 7 is removed from the machine and its frame 141 is turned on its hinge 139 to permit of the insertion of the test plate which is placed between the two clear glass plates 143 and 144. Said holder 7 is then returned to the machine and the lever 126 for the auxiliary shutter leaves 123 and 124 is moved so as to completely close said shutter. It being assumed that the hand wheel 102 is in such position that the knife edge of the post or pin 57 is engaged by that endof the winking lever 109 having the largest projection, the turning of said hand wheel will, through the pinion 104 and toothed segpivot or spindle, thereby causing the post 57 to be alternately moved away from said pivot "and permitted to thereafter swing toward the same. With each movement of the pin 57 away from the pivot 107 the shutter leaves 46 and 47 are turned on'their supporting pivots 53 and 54 a sufficient distance to bring one corner of the rectangular opening 56 into register with one corner of the rectangular glass covered opening 55 of the shutter leaf so that a maximum amount of light is permitted to pass from the source 9, through the lens 8 in such manner as to illuminate the front face of the test plate to a predetermined extent. Thereafter the post 57, being allowed to swing back into one of the recesses in the edge of the lever fment 105, turn this winkinglever on 1i-S 109, permits the shutter leaves to overlap sufiiciently to completely out off the passage of light through the lens. As the hand wheel 102 is turned slightly farther, the shutter leaves are again swung apart, but since the outer peripheral portions between the various recesses in the edge of the lever 109 are at a decreasing distance from the pivot or spindle 107 said shutter leaves are swung apart through lesser arcs than those previously moved through so that slightly smaller areas of the two rectangular openings' 55 and 56 are brought into line with each other; thereby permitting a smaller quantity of the light th hitherto to pass through the lens 8 and illuminate the front face of the test plate. The winking-lever 109 is thus keptmoving'until the operator making observations through the opening 4 is no longer able to distinguish the outhne of the cross on the test plate as reflected in the mirror 37, from the surrounding translucent portion thereof when said cross is illuminated by the successive. flashes of light; the winking action of the shutter leaves making it easier to judge when this ting down the quantity of light passing to' the rear of the negative holder byway of the three mirrors. 'The negative holder 7 may now be removed and thetest plate reholder. As is usual in photographic print-.

placed by a photographic negative with a sheet of sensitized paper or other material;

these two sheets being mounted between the glass plates 143 and 144 by placing them upon one of these latter after the frame holding the second plate has been turned suflicientlyon the hinge 139 to open-said ing, the sensitized surface of the paper is placed incontactlwith that surface of the negative on or in which the picture is formed and the holder 7, after being closed, is then inserted in the machine in such position that the sensitized surface of the paper is Dresented'to the front of the machine ;-that- .is directed toward, the lamp. The handwheel-120 is now turned until the pointer 155 is brought opposite an arbitrarily placed mark or name on the plate-134 indicative of or depending upon the particular grade or sensitiveness of the paper used, and such turning, through the spindle 119, turns the pinion 118, which through the teeth 116.

causes the. link 115Tto slide on the fixed block -117 into a definite position. Such movement causes the arm 114 attached to said link to sweep through an arc of greater or less extent, in which movement it necessarily. carries with it the'block 111. Since this movement of the block is necessarily to-- ward or from the spindle 167 of the winking lever 109, the'block 110 which slides-in the slot 108 of said lever, does not in any way eflect theadjustment of this latter, but the V block 112, which is likewise attached to the block 111, causes a turningof the indicator lever. 92 on its pivot, since its slot 93 is in-' clined to thejine of movement pf-the' threeblocks 110, 111, and112; it being obvious that in moving, the lever 92 necessarily carries with it the trip lever 97. Thereafter the operator, looking through the eyepiece ment, as I'have found that variations in the thickness of papers of the varieties ordinarily met with in practice, do not appreciably affect the adjustment either by reason of their partial opacity orbecause of differences in their thickness. The purpose of this winking or flashing operation is principally to avoid fatigue'of the eyes of the operator in adjusting or balancing the illumination of the two' faces of the negative to be printed from. As will be remembered, however, a certain amount of light is reflected from the mirrors? 30, 31 and 37 to the back of the sensitized paper in the holder, depending upon the amount ofopening of the auxiliary shutter leaves 123 and 124, so that as the two main shutter leaves 46 and '47 are winked between the extrenie positions indicated in Figs. 14 to 16 .75 paper does not interfere with this adjust inclusive, a point is finally reached at which thelight'ing effects through the openings 55 and 56 and from the mirror 37 are balanced and it is no longer possible'to distinguish the details of the negative in said mirror. This second photometric adjustment by means'of the hand wheel 102, swinging as it does the lever 109 on its pivot through the pinion 104 and toothed rack 105, slides the block .111 on the .bar 114 withouttendingto move said bar, and likewise causes the block 112 to swing the lever 92 on its pivot.;54. The machine is now adjusted for operation and the bar or plunger 64 is pressed downwardly to its full extent and is then released. From Figs. 6 and 17 it will be seen that the spring 72 is thus put under tension and the downward movement of the bar 64 is transmitted through the pawl 67 to the pin or post 68 on the short arm of the shutter opening lever 69. Said. lever is therefore turned on its pivot 54into the position shown in Fig. 18, until the downward movement of said bar has so far continued as to bring the arm 7 O of the pawl67 into engagement with the fixed pin or post 74, whereupon said pawl is so far turned. on its"supportin'g screw 66.

as'to disengage the post 68, thereby permitting the-shutter opening lever to return to the-extreme position: shown in Fig. 6 under the action of its. springflfi. This turning of the shutter opening lever 69 and its subsequent release just described first causes the bell crank lever 100 tobe moved from the position shown in" Fig. 17 to that illustrated and 4:7 to move and hold these in their full open positions, as in Fig. 19, against the action of their closing spring. The shutter leaves are thus fully separated or opened and light from the mantle 9 passes through the lens 8, through the negative in the holder and-acts upon the sensitized paper or other surface adjacent thereto to chemically change the same in the well known way.

The time of this exposure to the light, which,

in order to secure uniform results in the finished print, should depend upon the intensity of the light, the sensitiveness of the paper and the density of the negative, has, been provided for by the adjustments heretofore described and closure of the shutter at the proper time to eflect the correct exposure is caused inthe following manner.

In addition to the above action, the movement of the lever 69 from its normal posit1on when the bar 64.- is pushed downwardly,

causes its upper end to engage the upper end' of the timing lever 77 and turn it on its supporting spindle against the action of the spring 81 'into the, extreme right hand position shown inFig; 3. Such turning of the lever 77 through its segmental rack 78, causes turning of the pinion 89 and with it of the drum 83 which, owing to the arrangement of the pawls or dogs 84, does not cause movement of the gear wheel 82. When,

however, the shutter opening lever returns to its normal-position (Fig. 3), the tendency of the lever 77 to follow it under the action of the spring 81, tends to cause the drum 83 to be turned in such direction that it is immediately gripped by the pawlsor dogs 84, and it thereby becomes operatively coupled to the gear wheel 82. The said timing lever 77 is therefore permitted to move at a rate depending upon the escapement mechanism operative on said'gear wheel and under the action of the spring 81 gradually moves toward the shutter opening lever which is in its normal position. It will be noted, however, that the indicator lever 92 with the trip lever 97, has been adjusted to some position intermediate the ends of the curved guide piece 75, andthe parts are so arranged that the upper end of the timing lever, under the action of the escapement or governing mechanism, sooner or later comes into engagement with the upper end of said trip lever 97 which, as a result is turned on its pivot upon the indicator lever so as to move relatively thereto. Such turning, however, causes its short arm 98 to engage the projection or pin 99 of the bell crank lever 100, which is thus turned on its pivot 100 to such an'extent as to move its pin or post 101 out of engagement with the shutter post 57, thereby permitting the shutter leaves to be drawn by their spring into their overlapping or closed positions. The light from the mantle 9 is thus cut off from the negative and the sensitized paper, after which the holder 7 may be removed and the paper taken out and developed in the well known manner. The various parts of the machine are now in position for another operation, it being only necessary that the hand wheel 102 be adjusted for variations in the density of the negative until the image of\said negative as observed in the mirror 37, disappears, whereupon the bar 64 may be depressed to :open the main shutter leaves and give the proper exposure forthe particular negative in the machine.

As will'be understood by those skilled in the art, it is only necessary to adjust the hand wheel 120 when the grade of sensitized paperis varied, and it is necessary to use the test plate in order to vary the opening in the auxiliary shutter leaves 123 and 124 only when it is suspected thatsome variation hasoccurred' in the intensity of the light from the'mantle 9. I

If it be desired to use my invention for the purpose of making enlargements, itis hd plates 143 and 144 of the holder 7 which is reversed in position to bring the ground glass plate in front and thereafter the catch 14: is operated to release the angular piece 44 of the rear door 39, which may then be dropped'into the position shown in Fig. 24. The mirror 37 may now be let down until it rests on the bottom sill of the door opening: its'movement being controlled by the head or hand wheel 40. Thereafter the enlarging camera 160 is placed in line with the rear or dbor opening of the machine, and for this purpose said camera is preferablyprovided at its forward end with a tubular extension 161 having some form of catch such as a bayonet joint, whereby it is connected to the rear 'end 3 of the box 1 so as to be axially in line with the lens 8. The printing ma chine has at its front end a sliding or folding supporting member 170 to assist in supporting it in the position shown.

The camera is provided'with a lens 162 of the well known form a d also has a suitable paper holding device, which in the present instance consists of a plate of glass 163 mounted, on springs16 1 in such position that the sensitized paper may be mounted between senses it and the rear door 165' of the camera. Said ments previously made and by the increased distance of said sehsitized sheet from the lightsource.

is of course obvious that instead of 'constructing the machine to expose the paper to be printed with the lens 8 full openfor a variable period of time depending on the paper, light intensity, and density of the negative, I may so proportion the various parts that the main shutter leaves 46 and 47 will be operated to give variable apertures and all prints be made with the same time of exposure. The method of procedure above,

described is, however, decidedly to be preferred in View of the saving of time efiected by it. It is further obvious that the form and arrangement of the various shutter controlling levers and other parts whereby the adjustments of my machine aremade, may be widely varied without departing from my invention; which broadly contemplates the provision of a photographic printing a machine with means whereby the time of exposure td a source of light of a' sensitized surface to be printed may be varied to produce substantiallyuniform resultsinorde'r I to compensate for, and regardless of var1a-.

tions in, the intensity of the light, density of the negative, and the sensitiveness of the paper,,the invention contemplating mechanism including a photometric balancing de-' vice -for adjusting the mechanism to give the proper exposures necessary under the abovenoted variable conditions.

' if it be desired to shorten the length of the machine it may be constructed as shown in Fig. 26 with a projection 166 extending upwardly from its top surface and carrying the eye-piece 6 as well as the mirror 31. With such a construction the mirror 30 is placed as shown and the negative with the sensitized paper is introduced in the position shown atX; the light from the lamp 2 being reflectedv onto it from the mirror 37;

In any case, however, this modification in no way departs from my invention, but merely involves a rearrangement of parts without affecting the princ ples or mechanism employed.

It will be noted that the end or the indicator lever 92 is visible from the outside of the casing through a suitable glass covered opening and is operative adjacent the scale 95 and inasmuch as the position, of this indicator'on the scale is an indication of the adjustment of the tripping lever 97 itis obvious that by its use themachine may be adjusted to give a certain negative. and paper a definite exposure without the necesa sity for using the photometric adjusting devices It is to be-noted that the gas connection to the lamp is preferably so made as to permit relative movement of the gas supply pipe 11 and the burner 12 without set-ting up strains orjzausing leakage of gas and for this purpose said pipe T1 is rigidly connected to the lower portion of: the burnerproper, though as shown in Fig. 2 it swivels therewith the burner tube 12'.

l. The combination in a photographic printing machine of means for supporting a sensitized body and a negative; 'withautogmaticallyl acting means for exposing. said sensitized body and negative to a source of light "for a predetermined time; and a plurality qfcoacting independently adjustable devices for varying the time sai'd'body and negative are exposed to the light source.

\2. The combinatio n in a photographic printing machine of a source of light; means for supporting a negative and a sensitized body a shutter between the source and said supporting means;'mechanism for automatibody to be-prmted in position to have one face of saidrbody acted on by light from said source; mechanism for governing the time of exposure of the sensitized body to the light from the source means for illuminating the second face of 'said sensitized body; and means for adjusting said mechanism to vary the time of exposure in accordance with the conditions revealed by such illumination. I

4:. The combination in a photographic printing machine of a structure for support- 1 ing'a negative and a body of sensitized material to be printed; a source of light; a shutter for said light source; time controlled mechanism for causing closing of the shutter; means including an adjustable element for indicating variations inthe sensitiveness of said sensitized body; and means operatively connected to saidelement for adjusting said mechanism to compensate for such variations. 7 v

5. The combination in a photographic printing machine of a structure forsupporting a negative and a body of sensitized material to be printed source of light; a

shutter for said light source; time controlled mechanism for causing closing of the shutter; means including an adjustable element for indicating diflerences in the densities of different negatives; and means for operatively connecting said element to said time controlled mechanism to permit of adjustment of the latter to compensate for such differences.

6. The combination in a photographic printing machine of a-structure for supporting a negative and a body of sensitized material to be printed; a sourceof light; a

shutter for said light source; time controlled mechanism for causing closing of the shutter aftervit has been opened for a predetermined time; means for giving indication of variations inthe intensity of the light; and means for adjusting said time controlled mechanism to compensate for such variations.

7 The combination in a photographic printing machine of a structure for supporting a negative and a body of sensitized material to be printed; a source of light; a shutter for said light source; time controlled mechanism for causing closing of the shutter after it has been open for a predetermined time; means for adjusting said mechanism to compensate for difi'erences in the density 'of the negative and other means for adjusting the mechanism to compensate for differences in the sensitiveness of the sensitized body.

8. The combination in a photographic printing machine of a structure for supporting a negative and a body of sensitized material to be printed; a source of light; a

shutter for said light source; time controlled,

. mechanism for causing closing of the shutter after it has been open for a predetermined time; means for adjusting said mechanism to compensate for variations in the density of different negatives; and photometric means including a winking device associated with said adjusting means for giving visual indication when such adjustment has been perfected.

9. The combination in a photographic printing machine of a structure for supporting a negative and a body of sensitized material to be printed; a source of light; a shutter for said light source; time controlled mechanism for causing closing of the shutter after it has been open for a redetermined time; means for adjusting said mechanism to compensate for diflerences in the-intensity of the light source; and photometric means including a winking device operatively associated with such adjusting means for giving visual indication when said adjustment has been perfected.

10. The combination in a photographm printing machine of a structure for supporting a negative and a body of sensitized material to be printed; a source of light; a

shutter for said light source; time controlled mechanism for causing closing of the shutter after it has been open for a predetermined -.time; means for adjusting said mechanism to compensate for difierences in density the negatives employed; and 'photometric mechanism operatively associated with said means for indicating when said mechanism has been correctly adjusted.

11. The combination in a photographic printing machine of a structure forsupporting a negative and a body of sensitized material to be printed; a source of light; a shutter for said light source; time controlled mechanism for causing closing of the shutter after it has been open for a redetermined time; means for adjusting said mechanism to compensate for difierences in the intensity of the light source; and auphotometric device operatively associated with said mechanism for indicating when such adjustment has been correctly made.

12. The combination in a photographic printing machine of a structure for supporting a negative and a body of sensitized material to be printed; a source of light; a

shutter for said light source; time controlled mechanism for causingclosing of the shutter; a, device for delivering light throughthe negative; amount of light so delivered; the samebeing operatively connected to said. time controlled mechanism.

13. The combination in a photographic printing machine of a structure for support-- ing a negative and a body of sensitized material to be printed; a source of light; a shutter for said light source; time controlled mechanism for causing closing of the shutter after it has been open for a predetermined time; a device arranged to deliver light through the negative; means for illuminating the negative and sensitized body; means for adjusting the light delivering device to vary the quantity of light supplied; and means connecting the time controlled mechanism and said light delivering device for causing them to be simultaneously adjusted.

14. The combination in a photographic printingmachine of a structure for supporting a negative and a body of sensitized-material to be rinted; a source of light; a shutter for sald light source; time controlled mechanism for causing closing of the shutter after it has been open for'a predetermined time; means for illuminating the two faces of the negative; means for controlling said illumination; and means connected to said time controlled mechanism and to said illumination controlling means for simultaneously adjusting the latterand said time controlled mechanism.

15. The combination in a photographic printing machine of a casing; means for supporting a negative :fird abody of sensiand means for adjusting the t tized material to be printed; a source of light; a shutterfor said light source; means for opening the shutter at will, the same including a member operatively' connected to the shutter a movable bar having a'catch detachably engaging said member; means for tripping said catch; and time controlled mechanism set in operation by said shutter opening means, for closing the shutter after a predetermined interval.

16. The combination in a photographic printing machine of means for supporting a sensitized body and a negative; and auto: matically acting means for exposing said sensitized body and negative to a source of light for a predetermined time; thesame including a shutter; means tending to move the shutter from an open to a closed position; means for temporarily holding the shutter in an open position, the same including a lever; means for actuating the same; a second lever mounted on said first lever and operatively connected to the shutter; and escapement mechanism for actuating said second lever to release said holding means.

17. The combination in a photographic printing machine of a casing; means for supporting therein a negative and a body of sensitized material to. be printed; a shutter controlling the admission of light to the negative; means tending to close the shutter holding means forpreventing closing of the shutter; time controlled mechanism for governing the closing of the shutter; and'means for connecting the shutter and said time controlled mechanism; the same including atripping member for causing releasing of the shutter holding means; and a member for actuating said tripping member after the lapse of a predetermined time.

18. The combination in a photographic, printing machine of a shutter; means tending' to move the shutter from the open to the closed position; means for temporarily holding the shutter in its open position, the same including a pair of levers'ot which one is mounted upon the other; means for moving said latter lever at will; an adjustable tripping member for actuating said second lever to release the shutter; and time controlledmechanism including a member capable of actuating the tripping member in any adjusted position.

19; The combination in a photographic printing machine of a shutter; means for supporting a negative and a body of sensitized material to be printed; means tending to move the shutter from an open to a closed position; means for holding the shutter in its open position; an adjustable tripping member for releasing said. holding means; a photometric device for determin ng the adjustment ot'the tripping member, the same including an adjustable member operatively i connected to said tripping member; and

time controlled mechanism for actuating said tripping member in any adjusted position.

20..lhe combination in aphotographic printingmachine of a shutter; means for supporting a negative and a body of sensi- .'t-ized material to be printed; means tending to move the'shutter from an open to-a closed position; means for holding the shutter in its open position; an adjustable tripping member for releasing said holding means;

a photometric device having an element means tending to move the shutter from its open to its closed position; means for holding the shutter in its open position; tiu'ie actuating mechanism including a tripping member for releasing said holding means; means for adjusting the position of said tripping member to compensate for differences in the density of the negative; and means for giving visual indication when said adj usting means has been operated tothe necessary extent.

2-2. The. combination in a photographic printing machine of a casing; means for supporting the negative and a body of sensitized material to be printed; a shutter; means tending to move the shutter from its open to its closed position; means for hold- .ing the shutter in its open position; time 1nember for releasing said holding means; and two independent devices for ad usting ,the position of said tripping member in accordance with variations in the density of the negative and in the sensitiveness of the material to be printed.

23. The combination in a photographic printing machine of a casino; means for supporting a negative and a sensitized body to be printed; a shutter; time actuated mechanisnr including an adjustable member for causing closing of said shutter; with a photometric device for indicating the density of the negative; and including .a movable ele ment operatively connected to said adjustable member.

' 24. The combination in a photographic printing machine of a casing; a device for supporting a negative and'a sensitized body to be printed; a shutter having means normally tending to retain it in its closed position; means for holding the shutter in its open position; photometric means including a winking device for illuminating opposite faces of the negative; and time controlled