US2047851A - Machine for reproducing printing plates from pictures - Google Patents

Description

' J. A. BENNETT 51 I MACHINE FOR REPRODUCING PRINTING PLATES FROM PICTURES Original Filed June '25, 1932 6 Sheets-Sheet l Ju1 14,193e.- .J. A. BENNET-T I 2 1 MACHINE F OR REPRODUCING PRINTING PLATES FROM PICTURES Original Filed Ju ne 25, 1932 e Sheets-Sheet 2 y ,:1936. J. A..BENNETT. I 2,,047,8511 Y MACHINE FOR Ri PRoDucIN'e PRINTING PLATES FROM PICTURES Original Filed .June 25, 19:52 e Sheets-Sheet s i? F 1 r W y 1936- J. AJBENNETT 2,047,851

MACHINE FQR REPRODUCING' PRINTING PLATES FROM PICTURES Original Filed June 25, 1932 6 Sheets-Sheet 4 awe/whom an): w

- July 14, 1936. NE'fT MACHINE FOR REPRODUCING PRINTING PLATES FROM PICTURES 7 Original Filed June 25, 1952 6 Sheets-Sheet 5 3 its amen tom r1 r1 I L Ez iaifi i rziifi i m 5.9 m; .55: m s I Q: $2 k3 8 \t M m m. m m mmQ wo o o o44 Fn Q Nm v L V..- N.

. 1 A i P Km. m r r r r em *L/ZBeI IneZZ v July 14, 1936- Q J. A. )YBENNETT I 2,047,851

MACHINE FORREPRQDUCING PRIKTING PLATES FROM PICTURES 7 Original Filed June 25, 1932 e Sheets-Sheet a J Patented July 1 4 i936 iron mnonUciNG PRINTING v m'ms mom rrc'runns Joseph A. Bennett, Bloomln'g'ton, Ind.,

Blo'omlngton, Ind.

of forty-five per cent to Joseph W. Pieroy,

Application June 25, 1932, Serial No. 619,716

. Renewed September 24', 1935 I I This invention relates to machines for. auto- I matically engraving printing plates and particu- 'larly to means for engraving a plate ,in correspondence with variations of the light responsive element such 'as a phototron either affected by radio waves induced from-a 'distanceor afle'cted fby variations of lightpassing through a negative or reflected from a positive. p A black andwhite print is formed of-masses of black and masses of white. In a half tone plate, the picture is photographed onl the plate through a screen which breaks it up into dots more or less closely associated, the dots being line and wide-apart when the tone or shadow is light and closer and coarser where the plate is darker. In a half tone plate, however, there is no I full and positive black nor any full and positive white exceptwhere the plate is rented out.

' whichwill reproduce'upon a printed plate masses of pure black, masses of pure white and inter-- The general object of my invention is to proride an engraving machine of the character stated mediate tones grading by fine degrees into the pure black or into the pure white.

A further object is to produce an engraving ma- China of this character which will-automatically duplicate exactly in black and white and intermediate tones the picture which is being reproduced, whether this picture he in the form of a negative or a positive. Y t

A further object is to provide a machine of this character in which the engraving toolis' moved back and forth across the plate in successive, f parallel closely'approximating lines, the tool being depressed into the metal of the plate being produccdto a greater or less extent to thus cut wider or'narrower "white" lines in the plate, that is,

cut lines which will constantly vary more or less in width and further provide a machine of this character wherein the picture being reproduced and the reproduced plate are rotatable through j 90, or any other angle desired, so that after lines have been cut on the plate in onedirection, a second set of lines constantlyvarying in width may be'cut on the plate at a right angle to. the

i flrst-named set to thus cause the of the plate, in the intermediate tones thereof at least,

which is to print solid black being entirely uncut and that portion of the which is to print wtobe cut into dots. that portion of the surface solid white being cut away. V v g Afurther object is to provide a mechanism of i I this characterwherein the engraving tool israised r61" depressed by means of a'solenoidthis solenoid wb ing operatively connected with a light respon sive element which will cause the solenoid to vary ,its action upon the armature of the solenoid in 1 jconsonance with variationsin the amount of light gapass'ingthrough or reflected from the negative or co positive picture being reproduced.

ing tool and light responsive means for controlrelatively slight variations in the light responsive drawings, wherein:-,

A further object is to provide means in the 1 same machine whereby either a negative or a positive may be reproduced by the use 6f two light sensitivc elements, one of which receives lightrays transmitted entirely through the picture and 5 the other of which receives light rays reflected .from the face of the picture.

' Another object is to provide power operated means for reciprocating the cutter of an engravling the depth and, therefore, the width of. cut made.

A further object is to use in connection with the; tool controlling solenoid and with the light responsive element amplifying meansso that the element may be translated into relativelylarge v variations in the magnetism exerted by the solenoid.

.Other and more specific. objects will appear 9 more fully hereinafter. My invention is illustrated in the accompanying Figure 1 is a top plan view of the engraving 4 machineitself without the'electrical connectionsz'i' Figure 2-is a fragmentary section onfthe line" 2-2 ofFigure 1; I

' Figure 3 is a side elevation of the 7 A shown in Figure 1;

- Figure 4 is also 'a side elevatlonbut looking to- 1 in Flgure3; I.

ward the side opposite to that shown Figure 5 is a deflected view of the'transverse' feed ratchet; v Figure 6 is a section on'the line 8-6 ofFigure 4; Figure 7 is a vertical sectional view through the tool head showing the solenoid in section, the tool' being shown in elevation; V

Figure 8 is a face view or one of the armatur showing the diaphragm removed;

Figure 9 is a face view of the laminated core of 40 the field magnets; f

Figure 10 is a section. on'the line Ill-Ito! Figure 1;. i

Figure 11 is an electrical diagram showing the connections between the light responsive element, 5

the amplifier and the solenoid which operates 7 the. engraving tool; i

, Figure 12'is a very greatly enlarged diagram- I matic section showing the manner in which the cutter operates upon the metal plate; f 5

Figure 13 is a top plan view of a portion of a printing .plate showing a single line out therein;

Figure14 is a like view to Figure 13 but show-'. ing a printing plate with a plurality of longitudlnal lines cut therein varying constantly in their 55 width and showing how the lines will intersect each other to leave-black and white spaces;

Figure '15 shows diagrammatically a'surface of a printing plate in which" the cuts are disposed at right angles to eachother to form dots;

Figure 16 is a fragmentary front elevation of the forward face of the cutting tool;

Figure 17 is a transverse section through a printing plate after it is cut showing the manner in which the white and black spaces are formed by the cuts;

Figure 18 is a top plan view of the plate shown in Figure 1'7 to illustrate the manner in which this plate shown in Figure 17 will print;

Figure 19 is a face view of a portion of a plate showing the manner in which -the plate shown in Figure 1'? will print after it has been cut at right angles to the line shown in Figure 18.

Referring to Figures 1, 3, and 4, I0 designates a base or supporting frame comprising generally speaking two supporting bars II which may be in turn supported upon any suitable bed, table or other structure. Mounted upon these bars is a rectangular frame I! having the'end members I3. This frame has vertical walls as shown .best in Figure 3. This frame is fixed upon the beams or bars 'end of this bar is a picture supporting frame or table designated generally H, the details of which will be later described. This picture supporting table is longitudinally slotted as at I8 so that the table may move longitudinally into overlapping relation to guide M. A bridge I3 as shown in Figure 2 connects the table at the inner end of the slot I8 with the bar I6. It will be seen from Figure 1, however, that the bar I6 is formed integral with the table though I do not wish to be limited to this. The beams at their ends opposite the picture supporting bed I1 support a plate supporting bed generally designated 20 which is flanged upon one edge as at 2| and which carries the clamp screws 22 and the adjustable wall'23 mounted upon these screws so that this wall 23 may be shifted toward or from the wall 2| and thus clamp a printing plate between the walls 2| and 23 and hold the printing plate flrmly in place while it is being engraved. This printing plate is designated 24 in Figure 3.

Mounted upon the opposite end of the reciprocating bar l6, that is, the end opposite the picture support is a cutter which traverses the surface of the plate 24 to be engraved and which is controlled as will be later stated.

The means for reciprocating this sliding bar It with its picture table and with its cutter includes a shaft 25 as shown in Figure 1 which passes through and is carried by the frame II.

is'for' this reason that the pinion 38 is splined upon the power shaft 25. The gear wheel 28 is mounted upon a vertical post or support 23 extending upward from the guide |4. Mounted upon the shaft 30 of the gear wheel 28 as shown in Figure 4 is a disk 3| provided with a diamet rical undercut groove 33. Disposed within this groove is an outwardly projecting pin 33. This pin is adjustable along the groove as will be later stated.

Pivotally mounted upon the upright or post I 29 by a pivot 34 is an arm 35 which is longitudinally slotted at 38. The pin 33 passes loosely through this slot so that as the disk 3| rotates the arm 35 will be oscillated upon its pivotal center 34. 1

. Pivotally connected to the extremity of this 0 arm 35 is a-link 37 which in turn is pivotally connected in the manner shown in Figure 6 to the picture supporting end of the reciprocating bar l8. To this end, this bar I6 is provided with 15 the upwardly extending lug or flange 38 which is formed upon one sideface with the undercut slot 33.

Disposed within this slot is the flared end 48 of a pin 4| as shown in Figure 6, which pin passes 20 through an aperture in the link 31. The pin is centrally screw-threaded and extending through this pin 4| is the clamping screw 42 having a handle 43 so that when this screw is turned inward, the flared base of the pin 4| will be 25 clamped within the slot 39 in any adjusted position. when on the other hand the screw 42 is turned upward, the pin 4| may be adjusted along the slot 38 and then reclamped. Identically the same construction is used for holding the pin 33 30 clamped in any desired position within the slot 32, this pin being provided with adjusting screw,

the head of which is designated 44, which head is provided with a handle 45.

It will be seen that the pin 33 may thus be ad- 35 justed nearer to or further from the center of rotation of thedisk 3| so that the throw of the arm 35, the link 31 and, therefore, the range of reciprocation of the bar [8 may be regulated to fit the machine for operating on pictures of various dimensions. It will be obvious now that as the disk 3| is rotated, the cutter carrying bar I! will be reciprocated, carrying its cutter back and forth over the plate and, as shown in Figure 3, the form of the cutter is such that it will cut-into 45 the plate and cut a line in the face thereof upon a movement of the tool from right to left in Figure 3 and that it will do no cutting upon the return stroke.

For the purpose of giving a transverse traverse to the carriage which comprises the guides l4 and the bar l6 and the parts supported thereon, I provide as illustrated in Figure 1, the traversing screw 46 shown best in Figure 1, This screw is mounted in the ends of the frame I2 and at one end carries upon it the two reversely notched ratchet wheels 41 and 48.

The shaft also carries upon it the handle 43 whereby the screw shaft 48 may be rotated by hand to retract the carriage to its initial position d when desired.

Also mounted upon, the ratchet end of the shaft 46, as shown best in Figures 4 and 5 is an oscillating arm 53 carrying pivoted upon its .upper end the double pawls 5| and 52, these double 5 pawls being provided withthe integral handle ilwhereby the pawls may be thrown from one position to the other or held in an intermediate position, if desired, th'ese pawls coacting respectively with the ratchets 41 and 48. The arm 54 is oscillated by means of the link 34 which encases with a pin 5i p ojectin from a gear wheel 58, this gear wheel being driven by a pinion 31 mounted upon-the shaft 23 shown in Figure 1.

The face of the gear wheel 34 is diagrammatically 30' a 3'62 in Figure 10. Mounted in the rabbeted face slotted at so, this slot beingiundercutin the manner as are the slots 82 and 88 andthe pin 58 ' fleld magnets 84 and 85 connected in series and same i being constructed in the, same manner as the pins shown in Figure 6 so thatupon turning the handle 60, the base 8| of the pin will be jammed or clamped withinthe slot 58, this structure permit- ,ting the pin to be: shifted nearer to" or further 'u from the center of motion of the gear wheel 56 g or entirely across the gear wheel. By shifting this pin in this manner, a greater or less rotative movement may be communicated to thefeed screw 548 so that the step by step traversing movement "for the cutter or engraving tool across the face of the plate will be very slight or relatively coarse.

l5- 9 single traverse step is made upon the return movement of the'tool carrying bar ii to its initial ,It will be noted from this mechanism that a position which for purposes of illustration may be considered to be in the right hand upper corner v of the plate 24. V v

Thus the engraving tool moves'in one direction i along the plate to the full length of the stroke for which it isadjusted and is then retracted and when it is retracted, it is given a lateral movef ment of one step and then again cngraves a line acrossthe face of the plate and so on.

' "I will now describe the picture supporting means designated generally H which is shown in, t detailedsection in Figure 10. The picture sup-' porting frame, as it may be called, is designated of this frame 62 is a circular picture supporting frame 63 held in place upon the frame 62 bythe projecting members 84 which in turn are held in place by screws. Any suitable meansto this end i may be used. The frame 63 supports a plate of glass 65 if a negative is to be reproduced.

For the purpose of rotating the frame: 83 through 90, I provide the handle 86 attached to the" frame 63 and adapted to. engagethe right angularly positioned stopsGl and 68. Operating beneath the frame 88 are the framing orimasking iplates 69 and 10 disposed at right angles. to each other and movable upon rods Ii also disposed at -right angles to each 'other, each masking'plate I having a handle 12 whereby itmaybe shifted to I cut of! those portions of the plate through which light is not to pass. Any suitable maskingmean's I may be used, however.

@The tool or cutter controlling head shown particularly in Figures-3 and 7. Mounted upon i {the bar I8 is a frame, I3, this frame havingan opening 14 in its lower member. the frame being supported upon an approximately U-shaped element I5 which is attached to or forms part of the-bar IS. The frame and the member I! are i rigidly connected to the bar it under "any cir- ,cums'tances so that there can be no play.

[Pivotally mounted in the sidewalls of the member "upon a pivot pin .18 is alever 'I 'I', "the lower end of whichis angularly extended as at 18 in a direction toward the plate holder Jor clamp. This lever 11' may be bifurcated or [otherwise formed at its, lower end toipivotally ,pivot pin for this purpose is designated 80. The

, ,.;tool orcutter has an extension 81 extending upward parallel to the lever 11, the extremity of this extension being connected to thejglever ll 70' byatension spring 82. 'An adjusting screw 88 support the engraving tool or cutter .I 9."'The @passes through the extension 8| and engages Igagainst the lever 11 so that the angle r the cutter with relation to the. lever I1 and with relation to the .work may be adjusted. *1

u; f' rne tool controlling mechanism comprises the I rent to the armature coils.

wound upon the laminated iron cores 86. These cores support metallic elastic diaphragms 81 which are connected by 3 rod 88 tothe upper end of the tool operatinglever '11 in any suitable manner so as to move therewith. his to be understood at this point thatthe'total movement of the upper end of the lever is relatively slight.

, from zero to maximum depending upon the amount of light which passes through or is reflected from the picture on the picture supporting frame H, which light is directed upon a phototronic 'cell and affects an amplifier mechanism which in turn controls the passage of cur- Thes'e armature coils are energized from zero to maximum which is sufficient to cause the required maximum movement of the diaphragms 81 which in turn act upon the lever 11 to shift the cutting tool 18 vertically, a maximum amount of .004 inch. The. maximum energization of the armature coils raises the armature tool so that it will Just clear the surface of the plate. The normal position of the cutting tool when the armature coils are not energized is .004" below the surface of the plate. The maximum ener-' gizatio'n of the armature coil raises the cutting tool so that it will just clear the surface of the plate. Varying degrees of energization of the armature coils will cause the cutting tool to vary correspondingly within this range. Thus assuming that a negative is being used uponthe table and a beam of light is passing through the negative, then when a transparent portion ofa negative is scanned,,which transparent portion,- of course, represents a solid black portion of the picture, the tool is raised and the metal is not cut away, thus causing this portion of the plate to print as a solid black. When, however, the I scanning beam is obstructed by a dense portion of the negative, the weakened scanning beam which passes through thenegative .createsa correspondingly weaker energization of the photosult that the tool is not raised so much and the metal is cu away from the surface of the plate so that this portion will not print. Varying degrees of energizationof the armature coils will thus cause, the cutting tool "to vary correspondingly in its vertical position within therange of its shifting. As shown in Figures 4 and, 11, the

'tronic cell and the armature coilswith the refield-coils and magnets are contained within a casing 9| carried by the-frame 18.

As illustrated'in Figure 11, which as before remarked, is purely diagrammatic, a beam of light is discharged from a scanning light 92 of any' suitable chai'acter up through an aperture 93 in a diaphragm Qlf'and through a lens :85 which comes to a focus on the negative-98'. After passing through the negative, the beam passes upward through a lens 81 which directs it on to a light-sensitive element of known character carried within the phototronic cell 88. From one side ofthis cell extends the conductor -98 which leads to one pole or contact III! of a double-'- throw switch, the blades of which are designated IOI. Associated with this switch is the switch contact I02 which is connected by a conductor I03 to the scanning lamp 92.

It will, of course, be understood that the scan-' ning lamp 38 is held in a fixed position relative to the negative supported upon the table I1 and that the negative is movable in two directions beneath the scanning lamp bythe mechanism heretofore described and that as the negative is moved longitudinally by the disk gear 3|, the arm 35 and the link 31, the light striking the lens 91 and entering the phototronic cell will be constantly varied in consonance with variations in the light and the shade or density or thinness of the negative. This photoelectric cell is connected to amplifying means which in turn is electrically connected to the armature of the tool controlling solenoids. When the switch MI is thrown into engagement with the contacts I and I02, the lamp 92 and the electric cell 33 will be connected to a source of current.

Under some circumstances, it is desirable that .a positive be used in place of a negative and under these circumstances, the light must be cast downward upon the surface of the positive and be reflected to the photoelectric cell. I lllustrate this arrangement in Figure 11 wherein the lamp 92a which is the same as the lamp 92 is so disposed that the light beam coming from it is focused by means of the lens 95a upon the negative at one point and that this pencil of rays is reflected from the negative through the lens 91a into the photoelectric cell 98a. This cell is connected on one side by a wire I04 to the switch contact I of a double throw switch while the opposite contact I06 on the positive side of the switch is connected by the conductor I01 to the lamp 92a, the other pole of this lamp being connected by the conductor I08 to a conductor II5 extending to the push button switch II4 on the controlling panel. One electrode of each of the photoelectric cells 98 and 98a is connected, as before described, to the switch IOI, the other electrode-of each of these cells being connected by a wire I25 to the input of the ordinary radio amplifier II I.

It will be understood that the double-throw switch MI is designed for the purpose, in one position, of cutting in the lamp 92 and the photoelectric cell 98, and cutting out the lamp 92a and the photoelectric cell 98a and in its other position cutting in the lamp 92a and the photoelectrio cell 08a and cutting out lamp 92 and the cell 98. I

The wiring from the source of current to the amplifier, to the motor, the scanning lights and the wiring controlling the armature magnets, the photocell and the feed magnets is illustrated diagramatically in Figure 11. Y

The current is received by the wire H2 and returned to thesource of current by the wire H3. These wires -I I2 and H3 are preferably connected with a source of sixty cycle alternating current at 110 volts. The wire II2 extends to the binding screw of a push button control switch I I4 which is the main switch and from the other binding screw of this switch extends a wire Hi. This wire connects with the wire I00 leading'to the lamps 92 and 92a. This wire II5 also connects to one side of the motor I I6 which operates the driving shaft 25, the other side of this motor being connected by a conductor I I1 to a binding screw of the motor controlling switch II8, the other binding screw of this switch being -connected to the return wire 3, The return wire from the scanning light 02a is designated I01, this wire extending to the contact I00 of the switch "I, one of the blades of this switch being connected by a wire I to the push button switch 5 I 2I which in turn is connected to the line wire- H3. The scanning light 32 is connected on one side to the wire I08 and on the other side, as before stated, by the wire I03 to the contact I02. The amplifier is controlled by a push button switch I22, one binding screw of which is connected to the wire N3, the other binding screw being connected'by aconductor I23 to the input of the amplifier, the amplifier being connected in circuit with the wire II! by the wire I24. 15

Each of the photoelectric cells 96 and 03a are connected to the amplifier by the conductor I25 and then connected by a wire I26-to one of the binding screws of a push button switch I21 which controls the photocell, the other binding screw of this switch being-connected by a wire I26 to one of the switch blades IOI. The armature magnets are controlled by a push button switch I30, one binding screw of which is connected by, the wire I3I to one of the armature magnets.

. This magnet is connected in series with the opposed armature magnet which in turn is connected by the wire I32, to the radio amplifier at I33, which in turn is connected by the wire I34 to the tool magnet switch I by the wire I35. The field coils are controlled by the push button switch I36 connected: on one side by the wire I31 to the output of the amplifier which is connected by the wire I30 to one of the field magnets which is connected in circuit with the other field magnet, the last magnet being connected by the wire I39 to the other binding post of the field controlling push button switch I30.

It will thus be seen that the entire. mechanism may be cut'ofi from connection with the source of power by operating the main switch H4, that either of the scanning lights may be cut outfor cut in by operating the switch I2I that the motor may be cut in or cut out by operating the switch H8, that the amplifier may be controlled by the switch I22, the tool magnet controlled by the switch I30, the photocell controlled by switch I21 and the field magnets controlled by the switch I36 and that the switch IOI in one position connects the lamp 02 to the source of current and at the same time connects the photoelectric cell 03 .to the source of current or when in the other position connects the lamp 62a to the source of current and the photo cell 08a to the source of current.

It will be obvious, of course, that many changes might be made in the wiring without in any way departing from the spirit of the invention and that the wiring diagram in Figure 11 is merely given to shown one" manner in which the various parts maybe wired. V

The particular shape of the cutting tool or engraving tool 19 is best shown by reference to Figures 7, 12, an 16.

The lower end of the cutter is extended for- 05 wardiy at I40 and the forward face I of the cutter as shown in Figure 16 is triangular in form to provide a cutting edge which is V-shaped in cross section. This cutting tool is, therefore; a straight line cutting tool, that is, it cuts by being forced forward in a straight line plowing through the metal in the manner shown in Figure 12 and casting out the metal which is being cut in the form of' a thread ahead of the tool, thus leaving no ragged edges nor any detritus in the 76 out. The lower edge of the cutter is'extended upward and rearward as at I 42 at a slight angle and thenextended upward and rearward to the heel ofthe cutter at a sharper angle. ,l igure 12 plate but because ofthe shape of the;cutter,-it [follows that .the deeper the cut, the wider will the manner in which the cutter plows through the metal of the plate 24." As the amount of light-reaching the photoelectric cell j varies, the lever I1 is shifted in one direction or the other, thus forcing the cutting tool deeper into the metal or less deeply. The depth of cut has, of course, no bearing'upon" the completed 5 Abe/the cut and the narrower the cut the shallower the cut will be. Thisis shown clearly in Figure 1 3,which shows atop 'planiyiew of a cut made injconsonance with {the variations in 1 depth of the'cutter shown in Figure 12. The'cutter travels longitudinally of the plate and entirely across of the plate again making a second out parallel tothe first. If the cut is a wide one, that is,

if the cutter is forced deeply into themetal, a

second cut will interseoteither entirely or at intervals with the first named cut. Ifthe cut is! relatively shallow and, therefore, relatively narrow, the cuts may not intersect at all; If the cuts intersect along their entire extent, the

metal be entirely cut away from the face ofthe plate and asa consequence, this portion .of the plate will print-white. i

I If, on the other hand, the cutting toolis'raised- I, entirely from the face of the plate, this portion ofthe plate wlll'prlnt'black. If the cuts are relatively shallow and relatively narrow and ex- :tend parallelto each other, the plate will print asa series of white lines on ablack ground or black lines on awhite ground asshown in Figures '17 and 18 and if the plate with its white or black parallel lines or cuts is turnedjat right angles and cut, the plate will print a series of dots of varying degrees of area, with varying spaces between the dots as shown diagrammatically in Figure19 or as shown in Figure 15 where the. lines or cuts have been drawn not parallel tof'the side and end edges of the plate but an Qangle of'45 to these side and end edges.- If the plate has beenformed with the parallel cuts l a would be printed and if then the plate be turned shown in Figures 13 and 14 which intersect each other so that elongated white and black spaces at right angles and a series of cuts made, it will be obvious that the black spaces on the print made from the plate will be formed as dots,

squares, triangles, etc., of varying degrees of area that the entire surface of the plate will show masses of white, masses of black and intermediate tones formed of dots which maybe diaarry other form which when printed will give mend-shaped, rectangular, triangular or have --what is known as a half-tone eii'ect. Only the toneswill vary infinitely. Figure 17 shows di- -,ag'rammatically in cross section the manner in which aplate will be grooved. or cut toprint as shown in 1 'igurei'l8. Figure 19 shows .how a print made from a plate as illustratedfl-in Figural! will print if it be againcut at right angles a to the direction of cut shown in Figure 17, breaking the surface of the plate into a series oflarger. or smaller dots of varying area and possibly of varying shape.

In Figure 17, it is assumed that the depth of t the cuts a is' .0027, that the cuts designated 11 overlap .001" belowthe surface of the plateso s that this portion of the plate will print white I and that these cuts have a depth ofl004" be-' low the surface of the plate and that cuts 0 I have a d pth of .003'. while the cuts d have approximatelya depth of .001".v The deepest cuts 1c made where it is desired that this portion of the whichwill give a separation between the lines ranging from .0 to .0055, thus securing repro- 2 ductions which may be either used for news print, "antique" or anyother of the usual five classifications of paper stock. It is to be understood, of course, that the angle of the face I of the cutting tool is also to be changed for cutting different lines per-inch, this angle being capable of being changed by adjusting the screw 83;

The general operation of-this mechanism is as follows -The negative is placed in the, plate holder and framed" by the masks. The plate to be cut'is placed within the clamp or vise 20 in a position properly related to the position of the. negative (or positive). The plate may be a stereotype plate, a zinc or copper plate or of anyother suitable character. If a stereotype plate, it will either be cast in a stereotype box to type high (.918") or the conventional shell-, cast height and mounted on a wooden base. Copper or zinc plates may be' mounted in a sim ilar manner. The negative or positive and the plate to be engravedare positioned so as to be in direct relation. r The angle of. the tool pointis adjusted to secure the proper depth and the ratchet of the worm screw is set to give the proper spacing of cuts per inch to compare with screen lines per inch. Electric circuits are closed and the machine set, in motion. The bar l2 constitutesa ram. This ram' moves forward and the plate holder attached to the rear end of the ram moves likewise. The

negative (if a negative is used) moves between the scanning beam and the photocell and the tool is thrown in operation by the variations of the light energy acting on the photocell, the tool -5 varying in-its depth of out according to the density of negative. Where there are light parts in the negative, the tool rises and doesnot cut into the surface of the plate, thereby leaving the inking surfaces on the plate. The length of stroke is, of. course, adjusted by adjusting the pin 33 with relation to the center of motion of. the disk 3| andfthus' the ram movesforward the desired 0 fact that the negative holder is mounted upon the ram, the negative will pass over the scanning beam in a series of parallel lines and the tool will pass over the plate in a series of parallel lines. When the cuts have been completed in one direction, the machine is stopped and the plate is turned 90 and the negative 90".

While I have shown mechanism wherein the plate and negative are turned by hand throughv 90, it will be understood, of course, that automatic means might be provided for this purpose. The machine is placed in motion again and the same procedure is followed so that the second series of cuts made will be at right angles or at any other desired angle to the first series of cuts lar paper stock which will take a screen from 50 lines per inch to 1'75 linesper inch. Furthermore, since it is impossible to produce total white with the ordinary photochemical process used in making half tones, my machine has advantages in that it may beso adjusted as to cut out the surfags1 of the plate without routing procedure now us While I have before referred to the use of a negative from which the plate may be engraved, it is also obvious from what has gone before that a positive may be used and the light be reflected from the surface of the positive and by positive, I do not wish to confine myself tothe use of a photographic positive but my machine may be used to reproduce any picture from which the light mayxbe reflected, or any picture through which the light may be transmitted may be used as a negative.

The engraved plate is made on a flat surface and this platecan be immediately removed from my machine and placed on the press ready to be inked and printed. This machine will reproduce a printing plate directly from a negative or positive, will produce a half tone which is superior to the half tone produced by the photochemical methods in that it will produce both solid black and solid white and will give a clearer plate than by any other method known to me. It will reproduce any screen or tone block that is desired and any straight line effect or any solid white or solid black decorative design upon a border of solid black or solid white.

While in the above description I have referred more particularly to the use of this machine for the purpose of producing an engraved plate from a negative or positive, which negative or positive is mounted upon the ram I2, it is also obvious that radio waves controlled by a light beam transmitted through or from a picture and a long distance away may be transmitted through space in'the same manner as used for radio communication and be received by the amplifier which will vary the current passing through the armature of the cutting toolcontroller and that thus an engravingmay be made by my machine receiving its impulses, as they may be termed, from a long distance.

the engraving tool.

Attention is called particularly to the electromagnetic means whereby the variations in the current are translated into vertical movement of construction, the armature coils are submitted both to attraction and repulsion, one field magnet attracting while the other field magnet repulses and that thus a particularly strong action is secured upon the engraving tool to vary its depth of out.

I claim:

1. A machine for reproducing, a picture by ongraving upon the surface of a plate including a ram held from vertical movement but being longitudinally movable, a vertically movable engraving tool mounted upon one end of the ram,

Itwillbeseenthatinmy' engrave the plate in a series of successive parallel lines, and means for varying the vertical position of the tool with reference to the plate in consonance with variations inlight and shade of the picture comprising a dynamic armature light associated with the cell and picture support thereby to raise or lower the tool, oppose'd field coils carried by the head, means for constantly energizing saidcoils, armature coils coacting with and opposed to thefield coils, elastic diaphragms carried on the head, means rigidly connecting the diaphragms and the armature coils to said lever, and'means for passing current through the armature coils.

3. In an engraving machine, a cutter head, a lever mounted upon the cutter head and having an angular portion extending horizontally from the lever below the pivot thereof, an engraving, tool pivoted upon said angular portion for adjustment in a vertical plane, a screw passing through the upper end of the engraving tool and bearing against said lever, a spring urging the upper end of the engraving tool toward the lever, and means for oscillating said lever comprising constantly energized field coils, armature' coils disposed between the field coils and connected in series with each other, a rod connecting the armature coils to each other and to the upper end of the lever, and yielding means resisting movement of the lever from a normal position.

4. In an engraving machine, a cutter head, a lever pivoted thereon for oscillation in a vertical plane, a cutter carried by the lever and depressed or raised by the oscillations thereof, means for oscillating the lever comprising constantly energized field magnets carried on the head, each having a field coil and a'core, armature coils opposed to the field coils, a rod connecting the artive element, receiving light, from the picture, electromagnetic means for vertically shifting the so a.

"'igageoneofsaidratchet-wheels v fpositim to other of a amature coils rigidly to the upper end of the lever. 6i "fthe armature coils being connected in series'with I each other and with thesource of current, resilient diaphragms carried on the head resisting movement of thearmature coils and lever from 1 a medial position, the armature coils having their likepoles confronting each other, one of the field coils having a like pole opposed to the pole of the contiguous armature coil, the other field coil hav ing its unlike pole opposed to the contiguous pole of the armature coilwhereby to securerepulsion betweenone armature coil and thecorr'esponding fieldmagnet and an attraction between the other garmature coil and the corresponding field lolmagnetl' ,l 5. A machine for reproducing a I engraving upon the surface of a plateincluding :a m, .suides within which therein is reciprocawtable, a vertically movable straight line engraving tool carried upon one end of the ram, a picture support carried upon theother end of the ram, means for reciprocating the ram, meansfor adiustingthe length of such reciprocation, means actuated uponeach stroke of the ram to'cause a transverse movement of the ram, the picture I 1 support, and the engraving tool, manually controlled means for regulating the degreeof transpicture by verse movement .of the ram under the :action of 1 -saidil'astnamed means, the picture support being mounted on the ran: -.forrotative movement J through an angle of 90", means for supporting.

1;) the plate beneath'theengraving tooLsaid means 5 --,,permitting the plate to be) turned through an 1 angle of so, a scanning light disposed in con- ,iunctlon withthe picture supporhla'light-sensicarriedupon said ramfand 'includlng a dynamic armature operatively connected with o k the tool to vertically shift the tool and means. for f causing the j light-sensitive element to vary the current passing through said-electro-magnetic J in consonance'with'variationsln the light received upon said light sensitive element from the picture.

6. A machine for reproducing a picture by enupon" the surface of a. plate including reciprocatable ram, a guide therefor, a tool iheadhoiding member on'one end of the ram. a a 50 picture support carried on the other end of the *1 and havingmeans whereby a picture supported thereon maybe rotated from one position to another, means for operating the ram "mprislng a diametrically slotted disk, power rated means forrotatingsaid disk, an arm "v pivoted above the disused-having aglongitudiextendingslot, a pinipassing through said I slot and adjustable along the slot of'the disk to any desired positionnearerto or further from center thereof. alink pivoted to said arm adiustably conne'ctcdto the ramgfor adjustment into a plurality of positions longitudinally of the ram, a shaft extending at right angles to the ram, a frame within which the shaft is carried and operativaly connected to the-ram to therewith, a-screw shaft carried by said it and-having screw-threaded engagement jjwith ramf-a double ratchet wheel carried I the screw shaft. a lever mounted upon the and freely osclllatablethereonand carry- 7 ing a double pawladapted in one position to enand in' another rocating means ram for pivotal movement in a vertical plane,"

wheels, manually operable means connected to the screw shaft for reversely turningit, means for operating saidpawl carrying lever comprising a gear wheel having a diametrically slotted face, a. link pivoted to the pawl carrying lever at one end and at its other end adjustably connected to the slotted face of the gear wheel for movement nearer to or further from the axial center thereof, and means operatively'connected to the power shaft for-rotating said last named 1 gearwheel. 1- I 7.- A machine for reproducing a picture by engraving upon the surface of a plate including a reciprocatable ram, horizontal guides in which the ram moves, the guides preventing vertical the cutting tool being movable perpendicularly with relation'to the surface -of the plate to be engraved, means for supporting a plate to be engraved beneath the cutting tool, electro magnetic means for shifting the engraving tool vertically, a scanning light directed upon the picture,

a light-sensitive elementreceivlng light from the picture, means causing the scanning light to vary the amount of currentin the electro-magnetic means to thus vary. the position of the engravlng tool in correspondence with variations in the 80 light and shade of the picture, means for reciprocatingthe ram, said means; being adiustable to vary the; amount of stroke,gmeans for adjusting the ram longitudinally with relation to the recipmeans forgiving a step by step 85 transverse movement to the ram one step for a each stroke of the ram, said means being ad- H iust'able to vary the" amount-of this transverse movement, and means for initially adjusting the ,amount of" penetration of the cutting tool into the plate. l

8. In a machine for reproducing a picture by engraving upon the surface of a plate, a reciprocating mm, a lever moimted upon one end of the the lever having an angular extension, an engraving tool having its lower 'end V-shaped in cross section and pivoted to the angular extension of the'leverand extending above said pivot, an. adjusting screw passing through the upper end of ,the tool and bearing against the lever, a spring 1' urging the upper end of the tool toward the edge ofthe lever, a rod carried upon the upper end. 1 of the lever and extending in the plane of motion of the lever, opposed armature coils mounted upon the edge of the rod/and having their like poles confronting each other, field magnet coils disposed outward of the armature magnets, cores therefor, picture controlled means for varying the cinrent passing through th amhaving their like poles adjacent each other. the

coils of the armature being connected in series, and metallic elastic diaphragms mounted on the cores of the field coils and connected to the ormature. coils and the leverand yieldingly holding thesrmature coilsandtheleverin amedial' q

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