US3120180A

US3120180A - Screen stencilling machine

Info

Publication number: US3120180A
Application number: US165071A
Authority: US
Inventors: James A Black; Thomas J Rosema
Original assignee: General Research Inc
Current assignee: Advance Process Supply Co
Priority date: 1962-01-05
Filing date: 1962-01-05
Publication date: 1964-02-04
Anticipated expiration: 1981-02-04
Also published as: CH400979A; GB1033726A; DK120601B; CH420208A; DE1436497C3; GB1033727A; DE1436497A1; DE1436497B2

Description

Feb. 4, 1964 J. A. BLACK ETAL SCREEN STENCILLING MACHINE Filed Jan. 5, 1962 10 Sheets-Sheet 1 mn "mlnw- 50 2 INVENTORS l5 fime.s.A .Bladli BY Thomaslliosezzaa WITNESS M obe/6 0 10M? S. flaw/1217A).

(literacy Feb. 4, 1964 .1. A. BLACK 'ETAL SCREEN STENCILLING MACHINE 10 Sheets-Sheet 2 Filed Jan. 5, 1962 5 a j m am; 56 kfi n c W J v 4/ 3 J a w m." Wm H wm (VJ m a? 3 m o h JT ITT Fig. 6

WITNESS flVa/L/u S.

1964 J. A. BLACK ETAL 3,

SCREEN STENCILLING MACHINE Filed Jan. 5, 1962 o'sneets-sheet s W1 TNESS /7VO/UL7 3, 13mm 1964 J. A. BLACK ETAL 3,120,130

SCREEN STENCILLING MACHINE Filed Jan. 5, 1962 10 Sheets-Sheet 4 l lllvlllllllllvkllllll'yll:

EN TORfi JameaA..Bladk. &7 BY ThomasIRosezna WITNESS v A/M/u 5. 23mm (/1).

Feb. 4, 1964 J. A. BLACK ETAL 3,120,130

SCREEN STENCILLING MACHINE Y Filed Jan. 5, 1962 7 1O Sheets-Sheet 5 1964 J. A. BLACK ETAL 3,120,130

SCREEN STENCILLING MACHINE Filed Jan. 5, 1962 10 Sheets-Sheet 6 INVENTOILS EmeJA..Bla6i ThomadIROS'e m1 dale-wk amt-n F 1964 J. A. BLACK ETAL SCREEN STENCILLING MACHINE Filed Jan. 5, 1962 10 Sheets-Sheet 8 i INVENTORS Jame-sQLBlezci "\9- Iii 1% IRodema WITNESS Feb. 4, 1964 J. A. BLACK ETAL 3,120,180

SCREEN STENCILLING MACHINE Filed Jan. 5, 1962 10 Sheets-Sheet 9 I 5 I I I "WI"! ammmg A /a/vu 54340111111111).

Feb. 4, 1964 J. A. BLACK ETAL SCREEN STENCILLING MACHINE 10 Sheets-Sheet 10 Filed Jan. 5, 1962 Thp JfRose-ma ATTORNEY United States Patent 3,120,180 SCREEN STENCILLING MACHINE James A. Black and Thomas J. Rosema, Grand Rapids,

Mich, miguors to General Research, Inc., Grand Rapids, Mich., a corporation of Michigan Filed Jan. 5, 1962, Ser. No. 165,071 7 Claims. (Cl. 101-124) The present invention relates to automatic screen printing machines for screen stencil printing of coating material onto sheet stock.

The primary objects of the invention are to provide an improved screen stencil printing machine of the general type disclosed in Patent No. 2,606,492 issued August 12, 1952 to James A. Black, co-inventor of this invention; to provide such a machine which can more economically be produced without sacrificing any of the efiiciency of the earlier machine; to provide improved driving mechanism for such a machine which makes for higher speed operation and greater production; to provide improved gripper mechanisms for carrying stock sheets through the processing operation; to provide improved mechanism for elevating the squeegee of such a machine to permit set-up of the machine; to provide improved mechanisms for laterally registering the fed-in stock sheets prior to the processing thereof; to provide improved delivery mechanism for quickly removing the stock sheets from the machine after processing; and in general to provide a screen stencil printing machine which is improved in efiiicency, in manufacturing costs, and in appearance.

An illustrative embodiment of the invention is shown in the acompanying drawings, wherein:

FIGURE 1 is a top plan view of the new screen stencilling machine;

FIGURE 2 is a side elevational view of the machine;

FIGURE 3 is a horizontal sectional view of the machine taken on line 33 of FIGURE 4;

FIGURE 4 is an enlarged, fragmentary vertical sectional view of parts of the machine taken on line 4-4 of FIGURE 1;

FIGURE 5 is an enlarged, fragmentary vertical sectional view of other parts of the machine taken on line 55 of FIGURE 1;

FIGURE 6 is a vertical sectional view of the machine taken on line 6-6 of FIGURE 1;

FIGURE 7 is a horizontal sectional view of the machine taken on line 7 7 of FIGURE 6;

FIGURE 8 is a fragmentary horizontal sectional view of parts of the machine taken on line 38 of FIGURE 6;

FIGURE 9 is an end elevational view of the infeed end of the machine seen at the left hand side of FIGURES 1 and 2;

FIGURE 10 is a fragmentary elevational view of parts of the machine as viewed from the line 1010 of FIG- URE 7;

FIGURE 11 is an enlarged bottom plan view of the infeed table of the machine seen at the upper left hand corner of FIGURE 6;

FIGURE 12 is a fragmentary top plan view of portions of the infeed table which appear in bottom plan at the top of FIGURE 11;

FIGURE 13 is a vertical sectional view of the infeed table taken on line 1313 of FIGURE 11;

FIGURE 14 is an enlarged, fragmentary, vertical sectional view taken on line 1414 of FIGURE 15 FIGURE 15 is an enlarged top plan view of parts of the infeed table seen at the upper right hand corner of FIGURE 12, with a fragmentary showing of certain parts seen at the upper left hand corner of FIGURE 12;

FIGURE 16 in an enlarged, fragmentary top plan view of certain other parts seen at the upper left hand corner of FIGURE 12;

FIGURE 17 is a fragmentary vertical sectional view taken on line 17-17 of FIGURE 16;

FIGURE 18 is a fragmentary vertical sectional view taken on line 1818 of FIGURE 15;

FIGURE 19 is a fragmentary vertical sectional view taken on line 1919 of FIGURE 15;

FIGURE 20 is a fragmentary vertical sectional View taken on lines 2il20 of FIGURES 15, 18 and 19;

FIGURE 21 is a greatly enlarged fragmentary top plan view of the stock-supporting vacuum cylinder of the machine and showing gripper operating means associated therewith and driving means therefor, these parts being also shown to a smaller scale in the middle of FIGURE 3;

FIGURE 22 is a fragmentary vertical sectional view of parts thereof taken on line 2222 of FIGURE 21;

FIGURE 23 is a fragmentary vertical sectional View taken on line 2323 of FIGURE 21 and showing parts of the stock-supporting cylinder and grippers thereon in certain of their operating positions;

FIGURE 24 is a fragmentary vertical sectional view of parts thereof taken on line 2424 of FIGURE 23;

FIGURE 25 is a sectional view similar to FIGURE 23 and showing certain parts in other operating positions;

FIGURE 26 is also a sectional view similar to FIG- URE 23 and showing the parts in still other operating positions;

FIGURE 27 is still another sectional view similar to FIGURE 23 and showing the parts in even further moved positions;

FIGURE 28 is a fragmentary vertical sectional view taken on line 2828 of FIGURE 21;

FIGURE 29 is a perspective view showing the various parts of one of the gripper mechanisms in disassembled relation;

FIGURE 30 is a perspective view showing the various parts of one of the paper stop mechanisms in disassembled relation;

FIGURE 31 is a fragmentary vertical sectional view showing mecham'sm for vertically reciprocating the squeegee of the machine, the plane of section being indicated by line ESL-31 of FIGURE 32;

FIGURE 32 is a fragmentary horizontal sectional view of the same taken on lines 32-32 of FIGURES 31 and 34;

FIGURE 33 is a fragmentary horizontal sectional view of the same taken on lines 33-33 of FIGURES 31 and 34;

FIGURE 34 is a fragmentary vertical sectional view of the same taken on line 3434 of FIGURE 32;

FIGURE 35 is a fragmentary top plan view of the outfeed or delivery table seen on the right of FIGURES 3 and 6;

FIGURE 36 is a plan view of a fragment of one of the delivery conveyor tapes of the outfeed table;

FIGURE 37 is a fragmentary vertical sectional view of the outfeed table taken on line 3737 of FIGURE 35;

FIGURE 38 is a fragmentary end elevational view of the outfeed table;

FIGURE 39 is a fragmentary vertical sectional view showing a modified form of the outfeed table of the machine; and

FIGURE 40 is a fragmentary top plan view of this modified form of the invention.

Referring now in detail to these drawings, the various parts of the screen stencil machine there shown are housed within a frame which generally comprises spaced apart bases 49, 50, spaced

upstanding side walls

51, 52, transverse eonnecting bars 53, 54, 55. 56 and 57 (see FIGURE 6) connecting the

side castings

51, 52, and transverse channel bars 58, 59', 6t) and 61 mounted on the bases 49, St) for supporting various operating parts of the machine. The upper opposite ends of the side wall 51 at the left hand side of the machine as viewed in FIGURE 9, have inwardly turned

flanges

63, 64 on which are mounted the opposite ends of a longitudinally extending, cross-sectionally rectangular or square bar 65. The upper opposite .ends of the side wall 52 at the right hand side of the machine as viewed in FIGURE 9, have inwardly turned .fianges 66, 67 on which are mounted the opposite ends of a longitudinally extending, cross-sectionally circularly .formed or cylindrical bar '68.

A horizontally disposed stencil carriage is mounted for reciprocating movement longitudinally of the machine on posite. ends, all secured together to form a carriage of "great rigidity by any suitable means such as welding or screws (not shown). At its right hand side as viewed in FIGURE 9, the stencil carriage has longitudinally spaced

cylindrical bearing members

73, 74 which are closely fitted to and slidably mounted on the cross-sectionally circular bar 68 (see also FIGURE At its left hand side as viewed in FIGURE 9, the stencil carriage has longitudinally spaced, rectangularly slotted bearing

members

75, 76 which are slidably disposed on the crosssectionally square bar 65. In earlier machines of this type, both of the

bars

65 and 68 were cross-sectionally circular and'all fourv of the bearing members on the stencil carriage were cylindrical. These earlier constructions required extremely close tolerances between the bars and the bearing members so that no binding could occur as the stencil carriage moved through its reciprocating longitudinal movements on the bars. The present construction eliminates the need for such extremely close tolerances since only the two cylindrical bearing mem- .

bers

73, 74 need be in perfect alignment for guiding the stencil carriage in a true path, while the slotted

bearings

75, 76 at the opposite sides of the stencil carriage merely support the carriage in-its movement and need be closely fitted to the square bar 65 only at the latters top and bottom surfaces. This advance in the art effects a considerable economy in manufacture of this type of machine.

The screen stencil 77, which is conventionally a silk screen stencil but which may be also woven of plastic, metal or other filaments, is mounted across the bottom of a rectangular stencil frame 78 which in turn is secured to the stencil carriage for longitudinal reciprocating movementtherewith as by means of brackets 79. These parts are shown only in FIGURE 1 inasmuch as they are more .or less conventional. Also conventional is the squeegee assembly 80 which is mounted for raising movement off the screen stencil during the non-print stroke of the stencil to the left as seen in FIGURE 1, and for lowering movement onto the stencil to force coating material through thestencil and onto stock supported thereheneath during the print stroke of the stencil to the right. However, the -means for vertically reciprocating the squeegee assembly 80 and the ink flow coater 81 which is mounted for reciprocating vertical movement adjacent the squeegee are new and will be fully described hereinafter. The flow coater 81 distributes the printing ink over the upper surface 'of the screen stencil during operation of the machine.

sprocket wheel 85 around which passes an endless sprock et chain 86 which also passes around a sprocket. wheel 87 on the shaft 88 of a gear reducer 89 mounted on bars 90 which are in turn mounted on the channel bars 58, 59 of the machines frame. Suitable gearing Within the gear reducer 89 transmits the rotary movement, of shaft 88 to a shaft 91 of the gear reducer, which shaft 91 carries a crank arm 92 on its outer end, and a companion crank arm 93 is mounted on a short shaft 94 which is journalled in a triangular block 95 mounted on the channel bars 58, 59 of the machines frame. A crank bar 96 pivotally mounted on a shaft '97 which connects the outer ends of the companion crank

arms

92 and 93, operatively connects these crank arms to a rack bar 98 which is longitudinally reciprocally slidably mounted in a bearing block 99, the block 99 being mounted on the channel bars 60, 61 of the machines frame (see FIGURES 6, 7, 9 and 10). The provision of the companion crank arms, 92 and 93 reduces friction and ensures smoothness of operation, and thus makes possible greater operating speed of the machine than would be possible with only the single crank arm 92 The rack bar 98 meshes with a pinion 100 fixedly mounted on a transverse driving shaft 101 for reciprocating rotary movement in coordination with the reciprocating sliding movement of the rack bar. Shaft 101, which extends transversely across the machine, is journailed in pillow blocks 102,103 secured to the bearing block 99 and a pillow block 104 secured to a block 105 mounted on

channel bars

60, 61 at the opposite side of the machine from the bearing block 99.,

Gears

106, 107

are mounted on the shaft 101 at opposite sides of the machine for reciprocating rotary movement with this shaft 101. These

gears

106, 107 mesh with

gears

108, 109 respectively, which latter gears are mounted on a shaft 101 which extends transversely across the machine and which is journalled in pillow blocks 111, 112 (see FIG- URE 3) which are secured to bars 113, 114 mounted on the transverse cross-bars 54 and 56 of the machines frame.

Gears

108 and 109 mesh with racks 115 and 116 respectively which are on the underside of the stencil carriage at opposite sides thereof, and the stencil carriage is thus longitudinally reciprocated through print and nonprint strokes of the machine.

A stock-supporting cylinder generally designated 117 is mounted on shaft 110 for rotary movement beneath the stencil carriage and the squeegee assembly 80. In the generally designated, 118, and after processing are delivered over an outfeedtable generally designated 119;

These infeed and outfeed tables are hereinafter described inrdetail. As soon as a stock sheet 120 is released from the infeed table to the stock-supporting cylinder 117 for processing, the leading edge of the stock sheet is gripped by novel gripper mechanism on the cylinder, whichruechanism is best illustrated in FIGURES 21 through 29. A recess 121 is provided in the cylinder 117 and extends uansversely across the cylinder. A gripper shaft 122 is journalled in spaced bearing blocks 123 secured to the cylinder in vthe recess 121 as by means of screws 124.

This shaft 122 carries tripping blocks125 secured thereon by screws 126 (see especially FIGURE 28). These tripping blocks 125 are adapted to press upwardly against the lower or inner ends of plungers 127 mounted for radial sliding movement relative to the cylinder in hearing blocks 128 secured to the cylinder. inside the recess. 121.. 'Plungers 127 carry gripper elements 129 on their outer ends which have stock-receiving slots 130 adapted toreceive the leading edge of a stock sheet and, when the plungersmove radially inwardly, to clamp said leading edge against the edge of the cylinder adjacent the recess 121.. Springs 131 interposed between bearing blocks 128 and feet 132 on the inner ends of the plungers 127 normally urge the plungers and gripper elements 129 radially inwardly toward gripping position. The several parts of the gripper mechanism are shown disassembled in FIG- URE 29.

A cam follower 133 is mounted on the right hand end of shaft 122 as seen in FIGURE 21. This cam follower 133 is adapted to follow the outer camming periphery of a stationary cam ring 134 which is mounted on shaft 110 but which is prevented from rotating by means of an arm 135 secured to the cam ring 134 by means of a screw 136 and to the stationary outfeed table 119 by means of screws 137 (see FIGURE 23).

The operation of the gripper mechanism is illustrated progressively in FIGURES 22 through 28. When the cylinder 117 reaches the end of its non-print stroke in a counter-clockwise direction as seen in FIGURE 22, fingers 138 on the cylinder contact the leading edge of a sheet of stock 120 being fed to the cylinder, and move the stock sheet very slightly rearwardly or to the left so as to place the sheet in exact registry for transfer to the cylinder. Immediately thereafter the slots 13%) of gripper elements 129 engage the leading edge of the stock sheet as seen in FIGURE 23. At this time, the plungers 127 and gripper elements 129 are maintained in a radially outwardly moved position by means of a plate 139 pivotally mounted at 14% on the stationary cam ring 134 and urged in a counter-clockwise direction by a spring 141 into contact with a stop pin 142 on the cam ring. Also at this time, cam follower 133 which is being urged downwardly as seen in FIGURE 23 by spring 143, also urges plate 139 counter-clockwise against stop pin 142 because of the fact that the follower 133 is to the left of the plates pivot 140.

A very slight farther counter-clockwise movement of cylinder 117 to its position seen in FIGURE 25, causes the cam follower 133 to drop behind plate 139 so that when the cylinder 117 starts to move in a clockwise or print stroke direction as seen in FIGURE 26 cam follower 133, urged downwardly by spring 143, depresses plate 139 and moves it clockwise while the cam follower passes over the plate. The gripper mechanism clamps the stock sheet 120 to the cylinder 117 until the time the sheet moves onto the portion of the cylinder to which vacuum is applied through apertures 144 in the surface of the cylinder. The means for applying vacuum to the surface of the cylinder to maintain the stock sheet in position thereon during processing, is disclosed in United States Letters Patent No. 2,606,492 hereinbefore fully identified, and hence will not be described here in detail except to state that air is being constantly exhausted from the interior of the cylinder 117 on print strokes through a suction conduit 145 by means of a suitable exhaust pump 146 driven by a motor 146a, as shown in FIGURES 7 and 9.

After the vacuum has taken over to maintain the stock sheet in position on the cylinder during processing of the sheet beneath the stencil and the squeegee, cam follower 133 rides up onto the high segment of the cam ring 134 as seen in FIGURE 27, thus moving the gripper elements 129 radially outwardly and guiding the leading edge of the stock sheet outwardly for delivery onto the outfeed table 119 as seen in FIGURE 28. The outwardly moved gripper elements 129 then pass downwardly through slots 147 in the outfeed table.

Another novel feature of the invention resides in the mechanism for vertically reciprocating the squeegee 80 and the flow coater 81 during normal printing operation of the machine, and for automatically elevating these parts to inoperative high-lift positions when the machine is being set-up prior to normal operation. This reciprocating mechanism is best illustrated in FIG- URES 31-34, with reference also to the general views shown in FIGURES 1-9. As indicated in these views, the squeegee 81) is mounted on the upper ends of vertically disposed squeegee bars 148, 149 which are mounted for vertically reciprocating movement at opposite sides of the machine at approximately the longitudinal center thereof. The flow coater 81 is similarly mounted on the upper ends of vertically disposed

flow coater rods

150, 151 which are mounted near the squeegee bars 143, 149 for vertically reciprocating movement.

Referring now particularly to the detail views shown in FIGURES 31-34 which do not show the squeegee nor the flow coater 81 but only the squeegee bar 148 and the flow coater rod at the right hand side of the machine, it will be understood that as the squeegee bar 148 is reciprocated the squeegee itself is also raised and lowered, and as the flow coater rod 150 is vertically reciprocated the how coater itself is also raised and lowered. The squeegee bar 148 is reciprocable to three vertically moved positions, a lowered position shown in full lines in FIGURE 31, an intermediate position shown in dotted lines, and a high-lift position shown in broken lines in the same view. Likewise the flow coater rod 150 is reciprocable to three vertically moved positions, a lowered position shown in dotted lines in FIGURE 31, an intermediate position shown in full lines, and a highlift position shown in broken lines in the same view. During normal printing operation of the machine the squeegee bar 148 and the flow coater rod150 are oppositely reciprocated between their lowered and their intermediate positions so that during the print stroke of the machine the squeegee is in lowered, printing position and the flow coater is in elevated, intermediate position so as to distribute coating material over the upper surface of the screen stencil preparatory to the next print stroke. During the non-print stroke of the machine, the squeegee is in elevated, intermediate, non-printing position while the flow coater is in lowered position near the stencil for evenly spreading the distributed coating material over the surface of the stencil, and collecting excess material. The mechanism for oppositely vertically reciprocating the squeegee and the flow coater between lowered and intermediate positions, in coordination with the horizontal reciprocation of the stencil during normal printing operation of the machine, will next be described.

A camwheel 152 is mounted on the opposite end of the gear reducers shaft 91 from that on which crank arm 92 is mounted (see FIGURES 7, 9 and 31), the camwheel 152 being keyed to shaft 91 for rotation therewith. An operating arm 153 (see FIGURES 31-34) has a yoke 154 at its lower left hand end as seen in FIGURE 31, which yoke straddles the shaft 91 and carries a cam follower 155 at its outer end which bears against the periphery of carnwheel 152. As the camwheel 152 rotates and moves the cam follower 155 between its positions shown in full lines and in broken lines in FIGURE 31, operating arm 153 is reciprocated so as to reciprocate a crank arm 156 which has one end thereof pivotally connected at 157 to the end of operating arm 153 opposite the yoke 154 and which crank arm 156 is keyed at its other end to a shaft 158 journalled in bearing blocks 159, 16%) mounted at opposite sides of the machine.

A lever 161, also keyed on the shaft 158, is reciprocated with this shaft between a lowered position seen in full lines in FIGURE 31 and an upwardly turned position seen in broken lines in the same view. This lever 161 carries a roller 162 at its outer endthe right hand end as viewed in FIGURE 31, which roller contacts an adjustment screw 163 threaded in the lower end of a squeegee bar 148 thus to alternately raise and lower the squeegee bar 148 and the squeegee 89 between their intermediate and their lowered positions during the nonprint and print strokes respectively of the machine. A link 164 pivotally mounted on a boss 165 on the side wall 52 of the machine, has a pin and slot connection at 166 to the lever 161 and another pin and slot connection at 167 to the lower end of the flow coater rod 150. It will be seen that by this arrangement, when the right hand end of lever 161 moves upwardly, the left 'handend of link 164 is moved downwardly to lower the flow coaterrod 150 and the flow coater 81, and that when the right hand end of lever 161 moves downwardly, the left hand end of link 164 is moved upwardly to raise the flow coater rod 150 and the flow coater 81. The squeegee 80 and flow coater 81 are thus oppositely reciprocated between their intermediate and lowered positions during normal printing operation of the machine. Springs 168 connected to the machine's frame at 169 (see FIGURES 6 and 9) and to the operating arm 153 at 170 (see FIGURES 9 and 31) normally urge the parts of the mechanism just described toward their positions shown in full lines in FIGURE 31.

The automatic squeegee and flow coater high-lift mechanism for rendering these parts inoperative while the machine is being set up, i.e. when the stencil is replaced with, a different one and proper adjustments made, is another novel feature of the improved machine. In earlier machines this high-lift was eifected by hand lever or pedal operated mechanisms. The new automatic high-lift mechanism is best seen in FIGURES 6-9 and 3134.. The mechanism is driven by a separate reversible electric brake motor 171 shown in FIGURES 7, 8 and 9. This motor 171 when energized drives a transverse shaft 172 (see FIGURE 8) journalled in bearings 173, 174mounted on opposite sides of the machines frame, bymeans ofv an endless sprocket chain 175 passing around a sprocket wheel 176 on the motors shaft 177 and aroundanother sprocket wheel 178 on the shaft 172. Shaft 172 carries

pinions

179, 180 at its opposite ends Whichmesh with racks 181, 182 on the lower ends of bars 183, 184 which are mounted for vertical reciprocatory movement. Since only the bar 183 at the right hand side of the machine is shown in detail in FIG- URES 31-34, it alone will be herein described in detail but it will be understood that the mounting and operation of these bars 183, 184 are the same.

i The bar .1-83is comprised of an upper part and a lower part which are rigidly connected .together as by means of a screw 185 as seen in FIGURES 3'1, 33 and 34. The 'upper part of bar'183 is cylindrical and its extreme upper end 186 is reduced in diameterand projects through a cylindrical bearing 187 in a bracket 188 secured as by roller. 190 embrace the bar 183 therebetween. A clamp 195 is fixedly mounted on the cylindrical upper part of they bar 183 below the bracket 188 on the squeegee bar 148 by means of a bolt 1%. A tension spring 197 having its upper end fastened at 198 .to the bracket 188 and having, itslower end fastened at 199 to the clamp 19S, serves to urge the squeegee 'bar .148 downwardly relative to the bar 183 so that bracket 188 on the squeegee bar engages against the shoulder at the bot-tom. of the reduced upper end portion 186. of barl83. The spring 197 is sutliciently yielding to permit normal operation or" the squeegee bar 148 betweenits low position and intermediate position during printing operation of the machine.

When it is desired to move the squeegee '80 and the tflow coater 81 to the high-lift positions giving free access to. the stencil and the stencil carriage for set-up purposes, motor #171 is energized by means of a suitable pushbutton-switch (not shown). This rotates shaft 172 and pinions1-79, $180 which through racks .181, 1 82 move bars 183, 184 and

thesqueegee bars

148, 149 upwardly to their high positions as indicated by broken lines in FIG- URE 31. During this upward movement of the squeegee 80, arms 200 and-201 (shown only in FIGURE 1) on the squeegee bars 148, 149 engage beneath the fiow coater '81 so that the flow coater and its rods 1'50, 151 are also elevated to their positions indicated in broken lines in and the screen stencil 77 by one or anot vacuum registry devices installed in the feedboard 202 at opposite sides thereof; The registry device in the right .hand side of the feedboard 202 is shown in detail in FIGURE 31. When it is desired to lower the squeegee and flow water 81 totheir normal operating positions, wherein bars 183 rest on the

bars

49, 50 of the machines frame (see FIGURES 6 and 31) motor 171 is energized by means of a suitable pushbut-ton (not shown) to operate in a reverse direction. Suitable limit switches (also not shown) are provided for stopping the motor :171 when the squeegee and flow coater have reached their extreme high or low positions.

The infeed table 118 of the machine incorporates novel features for advancing stock sheets to the cylinder 117 for processing, and for correctly positioning the stock sheets laterally so as to properly register them with the stencil 77. This is especially important when the stock sheets are printed successively Withdilferent colored coating materials. I

The mechanism of the infeed table is best illustrated in FIGURES 1'1-20 of the drawings. The table comprises a feedboard 202 which is supported in the rear or on the left as seen in FIGURE 13 and near the bottom of FIGURE 11, by means of struts 203 secured as by screws 204 to the transverse connecting bar 53 or the machines frame and extending upwardly from said bar and secured at their upper ends to brackets 205 which are in turn secured to the underside of the feed-board 202 as by means :of screws 206. As seen in FIGURE 13, the right hand end ofthe feedboard 202 nearest the cylinder 117 is supported by. a transverse cross-bar 207 secured to the

opposite side walls

51, 52 by means not shown, the crossbar 207 being seen in. section in FIGURE 13 only. Endless conveyor tapes 208 are provided on the feedboard 202 for advancing stock sheets over; the feedboard from left to right as viewed FIGURE 13, said tapes 208 passing over pulleys 209 pivotally mounted on brackets 210 secured by screws 2111 to the underside of the feedboard 202, thence over the feedboard and around pulleys 212 pivotally mounted on brackets 216 secured by screws 214 to the underside .ofthe feedboard, and thence rearwardly under the feedboard and around pulleys 215 mounted on a driving shaft 216 journalled in bearing brackets 217 secured-by screws 218 to the underside of the ifeedboard, and finally over an adjustment shaft 219 mounted on brackets 217, and back to the pulleys 209,. Means for continuously moving these con veyor tapes 20 8 comprise a sprocket wheel 220 mounted on the driving shaft 216 and an endless sprocket chain 221 which passes around sprocket wheel 220 and a sprocket wheel 222 on a shaft 223 journalled in bearing blocks 224 secured to the underside of the teedboard 202 by meansof screws 225. The shaft 223 is in turn driven by a sprocket chain 226 (see FIGURES 6, 7 and 9) which passes around a sprocket wheel227 on the shaft 223 and a sprocket wheel 228 onthe outer end of the drive shaft 91 of the gear reducer -89.

A rectangular frame 229 (see FIGURES 1, 3, 12 and 13) is mounted on the upper side of the feedboard202 by means of screws 230. This frame 229 carries longitudinally extending flat metal bars 231 which overlie the conveyor tapes 208 and which have round apertures therethrough in which are loosely disposed metal balls 232 which weight the fed-in stock sheets downwardly against the con veyor ltapes. .The rearward or left hand ends of the metal bars 231 are desirably turnedupwardly as seen at 23 3 for guiding the fed-in stock sheets onto the infeed table. 7

The machine is equipped for printing either thimflexible paper sheets, or relatively thick, semi-rigid cardboard or other material. The sheets are brought into proper sidewise registrywvith the stock-supporting cylinder 117 ner of two novel FIGURES l420. The end of the feedboard 202 nearest the cylinder 117, is constituted by a metal plate 234. se-

cured to the main body of this feedboard by means of screws 235. The plate 234 has a transverse slot 236 therethrough. A tubular vacuum slide 237 is mounted on the underside of the feedboard for transverse sliding movement by means of bearing brackets 238 secured to the feedboard by screws 239, said tubular vacuum slide 237 having an upper part 240 extending through slot 236 and provided with suction apertures 241 therethrough. The ends of the tubular vacuum slide 237 are closed, and a vacuum conduit 242 leading from a valve 243 which is connected to the vacuum pump 146 by a vacuum conduit 244 (see FIGURES 7, 9, 11, 18 and 20) is provided for exhausting air from the vacuum slide 237 and creating suction at the suction apertures 241.

A side stop 245 for stock is mounted on the feedboard 282 for lateral adjustment to desired positions for correctly positioning stock on the feedboard. This side stop 245 has a threaded shank 246 thereon which passes through a bore in a block 247, said threaded shank 246 having lock nuts 248 thereon for securing the side stop 245 in adjustment relative to the block 247. The block 247 is secured to the feedboard 282 by means of screws 249 which may be threaded into any adjacent pair of a series of tapped holes 250 in the feedboards metal plate 234. Thus a wide variety of adjustments of the side stop 245 is possible through the combined positioning of the block 247 on the feedboard 262 and adjustment of the side stop relative to the block.

Means are provided for reciprocating the vacuum slide 237 so that successive fed-in stock sheets, when gripped by the vacuum on the slide 237, will be drawn thereby into contact with the side stop 2 .5 for correct sidewise posi tioning before processing. These means comprise a camwheel 251 which is slidably keyed on the shaft 223 for rotation therewith and for shifting movement thereon between a position for operating the vacuum registry device at the left side of the feedboard as shown in dotted lines in FIGURE 1 1, and a position for operating the vacuum registry device at the right side of the machine as shown in broken lines in FIGURE 11 and in full lines in FIG- URES l8 and 20. The high part 252 of camwheel 251 is adapted to intermittently contact a roller 253 on a bar 254 secured by screws 255 to the vacuum slide 237 and thus move said slide to the right to bring a sheet of stock up against the side stop. Thereafter slide 237, bar 254 and roller 253 are again moved to the left by the force of a compression spring 256 interposed between the slide 237 and a bracket 257 secured by a screw 258 to the metal plate 23 at the right hand end of slot 236.

The vacuum stock-positioning device on the left hand side of the feedboard is the same as that shown on the right hand side except that as here shown (at the left side of FIGURES 11 and Y12) the side stop 259 is mounted on the tubular vacnurn slide 26% for movement therewith, instead of being fixedly mounted on the feedboard 262. Thus, instead of being a vacuum pull-over for the stock, this device is rather a push-over device whereby the stock is pushed by the stop 259 into proper sidewise alignment. The step 259 is mounted on the slide 269 by means of a device indicated at 261 secured to the slide by means of screws (not shown) threaded into the suction apertures 262 of the slide 260. Suction can be created at the apertures 262 through a vacuum conduit 263 connecting the vacuum slide 26% with valve 243. If desired the vacuum registry devices at both sides of the feedboard 292 can be devised so as to be adapted to receive either the side stop 245 for pull-over registration, or the side stop 259 for push-over registration.

Stop means are provided for halting each stock sheet in its forward movement across the feedboard 2%2 until the precise moment when the grippers on the cylinder 117 are in position to receive the leading edge of each sheet. For flexible sheet stock, these stop means comprise arms 264 (see FIGURE 29) secured by screws 265 to brackets 266 which are mounted on and turnable with a shaft 267 journalled in bearings 268 secured to the upper side of the metal plate 234 by means of screws 26-9. (A disassembled paper stop is shown in FIGURE 30). Shaft 267 is reciprocally rotated for coordinated movements with the other moving parts of the machine by means of a lever 270 seen at the extreme left of FIGURES 12, 16 and 18. This lever 270 is fixedly mounted on the extreme left hand end of shaft 267 and has an arm 271 depending through a slot 272 in the metal plate 234 and provided with a roller 273 which bears against a camwheel 274 on shaft 223. The stop arms 264 have downwardly turned forward ends 275 which are normally urged upwardly to inoperative positions by a spring 276 (see FIGURE 20) which is secured to the upper rearward end of lever 276 by means of screws 2 7-7 and which bear upwardly against blocks 278 secured to the feedboard 2&2 by means of screws 279. When the downwardly turned forward ends 275 of arms 264 are turned downwardly by the action of camwheel 274 on roller 273, lever 270 and shaft 267, they are in position to stop the forward movement of a stock sheet. Bifurcated arms 280 also mounted on shaft 267 by means of brackets 281 and screws 282, operate to press the leading edge of the stock sheet downwardly against fingers 283 secured to the underside of metal plate 234 by means of screws 284 (see FIGURE 20), thus to ensure proper entry of said leading edge of the stock sheet into the grippers on the reciprocating cylinder 117.

For heavy cardboard stock, the stop means for halting each sheet of stock in its forward movement over the infeed table until the precise moment for its release to the stock-supporting cylinder 117, comprise arms 285 at opposite sides of the metal plate 234, the forward ends of which are turned downwardly at 286 to form a stop for the cardboard. The rearward end of each anm 285 is secured by screws 287 to a block 288 which in turn is secured by screws 289 to a slide 2% mounted for lateral sliding movement in slide bearings 291 secured to the underside of the metal plate 234 by means of screws 292 and projecting upwardly through slots 293 in the metal plate 234 (see FIGURES l5 and 19). Each slide 2% has a bracket 295 (see FIGURE 19) secured to its outer end by means of a screw 2% and provided with a depending arm 297. Air chambers 293 (see FIGURES 11 and 19) mounted on angle brackets 29? secured to the underside of the metal plate 234 by means of screws 3%, are intermittently supplied with air pressure through conduits 391 from a source not shown, and this intermittent air pressure is transmitted to a pair of bellows 362 interposed between the air chambers 298 and the depending arms 297 on brackets 295. The cardboard stops 285 are normally maintained in inwardly moved positions for checking forward movement of the cardboard sheets by means of tension springs 303 each of which is connected at one end to a bracket 364 secured to the underside of the metal plate 234 and at the other side to slide 290. The cardboard stops 285 are simultaneously moved oppositely outwardly to release successive stock sheets to the cylinder 1-17 at the precise moment when the grippers on the cylinder are in position for receiving the leading edge of a stock sheet, by the intermittent air pressure supplied to the bellows 392 in coordination with the other moving parts of the machine.

The outfeed table 1'19 of the machine is best seen in FIGURES 1, 3, 6 and 35-38. This outfeed table comprises a delivery board 365 which is mounted at its end nearest the cylinder 117 on brackets 366 by means of screws 307, the brackets 396 being secured by means of screws 308 to a transverse bar 399 having its opposite ends mounted on the machines frame at the opposite sides thereof. The delivery end of the delivery board 305 is mounted on brackets 319 which are secured by means of screws 311 to a transverse bar 312 which also has its opposite ends secured to the machines frame. As best seen in FIGURES 37 and 38, the delivery end of the delivery board 305 has a depending cross-member 313 secured to the underside thereof, and screws 314 passing through apertures in the brackets 310 and threaded into the crossmember' 313 secure this end of the delivery board 305 to the brackets 310. v

Delivery conveyor tapes 315 are driven over the delivery board 305 in the direction of delivery, said tapes passing around a roller 316 turnably mounted on a shaft 317 having its opposite ends mounted on the brackets 310, thence under the delivery board and around a roller 318 turnably mounted on a shaft 319 having its opposite ends secured to the brackets 3G6, thence downwardly and around drive pulleys 320 mounted on and rotatablewith a drive shaft 321 having its opposite ends journalled in depending brackets 322 secured to the transverse bar 389 by means of screws 323, and finally upwardly and around pulleys 324 turnably mounted in apertures 325 in the delivery board 305. The shaft 317 which carries the roller 316 at the delivery end of the delivery board 3&5 hasits opposite ends disposed in elongated slots 326 (see FIGURE 38) through the brackets 310 and secured therein by means of screws 327 turnably mounted in the brackets and threaded through the ends of the shaft 317. By this means the shaft 317 and roller 316 may be adjusted to take up any slack in the conveyor tapes 315. The drive shaft 321 for driving the delivery conveyor tapes 315 is driven by means of a sprocket chain 328 (see FIGURES 4, 6, 7 and 8) which passes around a sprocket wheel 329 on the pulley drive shaft 321 and around a sprocket wheel 330 on shaft 88.

, A novel feature of the delivery table is the vacuumizing of the delivery tapes 315. These tapes are provided with suction apertures 33 1 which register with elongated suction openings 332 through the delivery board 305 during passage of the tapes over, the delivery board. A longitudinally elongated sheet metal enclosure 333 is secured to the underside of the delivery board beneath each conveyor tape 315 bymeans of screws 334. Air is exhausted from the enclosures 333 through ductwork including a conduit 335 extending from an exhaust pump 336 to a transversely elongated enclosure 337, and individual ducts 33-8 leading from the enclosure 337 to the enclosures 333 beneath the delivery conveyor tapes 315, and secured to the enclosures 333 by means of screws .39. Printed stock sheets are thus caused to positively adhere to the conveyor tapes as they are drawn off the cylinder 117 after processing. Voids 339 and 340' (see FIGURE 35) are provided in the end of the delivery board .305 to permit passage of the gripper elements 129 and the fingers 138 respectively, on the cylinder 117, past the outfeed table 119.

Operation Stock sheets, either of thin paper or of relatively thick cardboard or the like, are fed into the machine at its left hand side. as viewed in FIGURES 1 and 3, over the in tfeed table 118 and conveyor tapes 231. During their travel over this infeed table, each sheet is moved laterally into correctly registering position by one of the suction pull-over or push-over devices located in the infeed table near the cylinder 117. This lateral positioning of the stock before processing is especially important when stock is run several times for diiferent colors which must all register. Before being released to the reciprocating cylinder 117 for processing, each sheet is halted in its forward movement by movable stops, the movement of which is coordinated with the movement of the cylinder 117 and the stencil 77. For thus stopping paper-stock in 7 'tion as viewed in the drawings, the stock stops 264 or 285 release a sheet of stock to the. grippers 129, the squeegee 89 is lowered onto the stencil 77, and the machine ,opcrates through its print stroke with the cylinder'117 moving clockwise to support and carry the stock, and with the stencil 77 moving to the right as viewed in the drawings, while the squeegee 80 forces coating material through the stencil 77 and onto the stock 120.

After processing each sheet, the stencil 77 is moved to the left and returned to its starting position, the cylinder 117 is rotated counter-clockwise to its starting position, the squeegee 8t) is elevated off the stencil 77, and the printed stock sheet is delivered over the vacuumized delivery or outfeed table 119.

The novel features of the machine reside in the provision of the cross-sectionally square bar 65 which eliminates the extremely close tolerances required in earlier machines, the rack and pinion drive mechanism with companion driving cranks 92 and 93 which provide for higher speed operation, the improved sheet gripper mechanisms on the stock-supporting cylinder 117. The automatic squeegee high-lift for use when the machine is being setup for a stock run is also an improvement in the machine, as are the vacuum pull-over and push-over devices for drawing or pushing stock sheets laterally into correct printing registry, the improved temporary stops for halting either paper or cardboard stock in its forward movement before being released at the precise moment for processing, and the efficient vacuurnized outfeed table for delivering the .printed stock after processing.

FIGURES 39 and 40 illustrate a modified form of the outfeed table. Stock sheets printed by the screen stencil method have a tendency to adhere to the bottom of the screen stencil after processing, due to the tackiness of the coating material used. In FIGURES 39 and 40 there is illustrated suction means associated with the outfeed table for positively drawing the printed stock sheet away from the screen stencil. These means comprise enclosed vacuum chambers 400 attached to the end of the delivery board 305 adjacent the cylinder 117 as by means of screws 461, these chambers being provided with suction apertures 402 in their upper ends. Air is exhausted from the vacuum chambers 400 through a conduit 403 by means of a vacuum pump (not shown), in intermittent timed relation with the reciprocation of the cylinder 117. FIGURE 39 shows a stock sheet 120 being drawn by the vacuum at the suction apertures 402 from a position of adherance to the screen stencil 77 as seen in dotted lines in this view, to a position adhering to the vacuumized delivery tapes 315 as seen in solid lines. It has been found that the leading edge of the .stock sheet will carry over from the cylinder to the vacuumized delivery tapes 315, and the timing of the intermittent vacuum applied to the vacuum chambers 400 is such that as soon as the leading edge of a printed stock sheet reaches the vacuumized delivery tapes, a vacuum suddenly applied to the vacuum chambers 400 and thus to the suction apertures 402 will strip the printed sheet off the screen stencil. This is another novel feature of the improved machine.

While but two. specific embodiments of. the invention have been herein shown and described, it will be understood that numerous details thereof may be altered or omitted without departing from the spirit of the invention as the same is defined by the following claims.

We claim:

1. In a screen stencilling machine: a frame; a stocksupporting cylinder mounted on the frame for rotary movement; a screen stencil mounted on the frame adjacent .the cylinder for reciprocating movements longitudinally of the machine through print and non-print strokes of the machine; a squeegee mounted on the frame for vertical reciprocation between an inoperative highlift position, an intermediate elevated position oh the screen, and a lowered position onto the screen for forcing coating material through the stencil and onto stock supported by said cylinder; a flow coater mounted on the frame for vertical reciprocation between a lowered position for collecting coating material from the screen stencil, an intermediate elevated position for distributing coating material over the surface of the screen stencil, and an inoperative high-lift position; first means for ppositely vertically reciprocating said squeegee and fiow coater in coordination with the horizontal reciprocation of the stencil during normal operation of the machine so that during the print stroke of the machine the squeegee is in lowered position while the flow coater is in intermediate elevated position and so that during the nonprint stroke of the machine the squeegee is in intermediate elevated position while the flow coater is in lowered position, said first means comprising levers mounted for reciprocating rotary movements at opposite sides of the machine and adapted to bear at their outer ends against the lower ends of the squeegee bars for vertically reciprocating said bars, links independently mounted for reciproeating movements at opposite sides of the machine, each of said links having one end thereof pivotally connected to one of said levers between said levers pivotal connection to the frame and said levers end adapted to bear against the adjacent squeegee bar, and each link having its end opposite its pivotal connection to said lever pivotally connected to the lower end of the adjacent flow coater rod, and means for reciprocating said levers in coordination with the horizontal reciprocation of the stencil; and second means for simultaneously elevating both the squeegee and the .fiow coater to their inoperative high-lift positions.

2. In a screen stencilling machine: a frame; a stocksupporting cylinder mounted on the frame for rotary movement; a screen stencil mounted on the frame adjacent the cylinder for reciprocating movements longitudinally of the machine through print and non-print strokes of the machine; an infeed table for feeding sheet stock to said stock-supporting cylinder comprising a feedboard having a laterally extending slot therethrough at one side thereof and near the cylinder; a slide bearing mounted on the underside of said feedboard beneath said slot; a tubular vacuum slide member slidably disposed in said slide bearing and extending upwardly through and movable laterally in said slot, said tubular slide member having a plurality of suction apertures therein extending from the interior thereof through its top wall; means for exhausting air from the tubular slide member to create suction at said suction apertures for gripping a stock sheet fed over said feedboard; a side stop mounted on the upper surface of said feedboard above said slide member; means normally urging said slide member laterally inwardly in said slot; and means for moving said slide member laterally outwardly in said slot to pull a stock sheet gripped thereby sidewise into proper registering position against said side stop during the sheets travel over the feedboard.

3. In a screen stencilling machine: a frame; a stocksupporting cylinder mounted on the frarne for rotary movement; a screen stencil mounted on the frame adjacent the cylinder for reciprocating movements longitudinally of the machine through print and non-print strokes of the machine; an infeed table for feeding sheet stock to said stock-supporting cylinder comprising a feedboard having laterally extending slots therethrough at opposite sides thereof and near the cylinder; pairs of slide bearings mounted on the underside of said feedboard beneath said slots; slide members slidably disposed in said slide bearings and extending upwardly through and movable laterally in said slots; stop means on the upper side of said slide members for stopping a stock sheet in its advancing movement over the feedboard when the slide members are in laterally inwardly moved positions; and means for laterally reciprocating said slide members and stop means between inwardly moved positions for stopping stock sheets and to outwardly moved positions for releasing each sheet to said stock-supporting cylinder in timed relation to the reciprocating movements of said stencil.

4. A screen stencilling machine according to claim 3 in which the means for laterally reciprocating said slide members and stop means comprises bellows interposed between members on the feedboard .and on the slide members and means for intermittently inflating and deflating said bellows.

5. In a screen stencilling machine: a frame; a stocksupporting cylinder having an axial shaft mounted on the frame for rotary movement; a screen stencil mounted on the frame adjacent the cylinder for reciprocating movements longitudinally of the machine through print and non-print strokes of the machine; means for forcing coating material through the stencil and onto stock sheets supported by the cylinder during print strokes of the machine; a gripper shaft mounted for reciprocating rotary movements in a recess in the cylinder; tripping blocks spacedly mounted on said gripper shaft; plungers mounted in a recess on said wall of the cylinder adjacent said recess for reciprocating radial movements relative to the cylinder and adapted for reciprocation by said tripper blocks; gripper elements mounted on the outer ends of said plungers and provided with stock-receiving slots adapted to grip the leading edge of a stock sheet at the beginning of the machines print stroke and to clamp said leading edge to the cylinder; and means for imparting coordinated reciprocating movements to the stencil and the gripper shaft, said last-mentioned means comprising a cam follower mounted on one end of the gripper shaft; a cam ring rotatably mounted on the rotatable cylinder shaft for moving the cam follower and the gripper shaft toward and away from gripping positions in phase with the reciprocating rotary movements of the cylinder; a plate pivotally mounted on the cam ring for turning movement to a first position wherein the cam follower is lifted off the cam ring thus to rotate the gripper shaft to a position wherein the stock-receiving slots on the gripper elements are adapted to receive the leading edge of a stock sheet, said plate being also turnable to a second position wherein the gripper elements are permitted to clamp said leading edge of the stock sheet to the cylinder, and means for quickly moving said plate to its first position and then to its second position upon completion of the non-print stroke of the cylinder.

6. In a screen stencilling machine: a frame; a stocksupporting cylinder mounted on the frame for rotary movement; a screen stencil mounted on the frame adjacent the cylinder for reciprocating movements longitudinally of the machine through print and non-print strikes of the machine; an outfeed table for delivering stock sheets from said stock-supporting cylinder after processing comprising a delivery board; and suction means disposed between the stock-supporting cylinder and the end of said delivery board adjacent thereto for drawing stock sheets away from said screen stencil after the processing thereof.

7. Ln a screen stencilling machine: a frame; a stocksupporting cylinder mounted on the frame for rotary movement; a screen stencil mounted on the frame adjacent the cylinder for reciprocating movements longitudinally of the machine through print and non-print strokes of the machine; an outfeed table for delivering stock sheets from said stock-supporting cylinder after processing comprising a delivery board; suction means disposed between the stock-supporting cylinder and the end of said delivery board adjacent thereto for drawing stock sheets away from said screen stencil after the processing thereof; endless conveyor tapes mounted on the delivery board for continuous movement over the board in a direction for delivering the sheets from the stock-supporting cylinder, said tapes having aperttnes therethrough, and said delivery board having suction openings therein beneath said tapes; and means for ei- References Cited in the file of this patent UNITED STATES PATENTS 649,001 Scott May 8, 1900 1,495,257 Dudley May 27, 1924 1,585,369 Blaine May 18, 1926 16 Backhouse July 4, 1939 Battey et a1 Sept. 23, 1941 Trump July 4, 1944 Albrecht Nov. 7, 1950 Black Aug. 12, 1952 Norton Dec. 25, 1956 Morse July 9, 1957 Black Dec. 30, 1958 Black Dec. 22, 1959

Claims

1. IN A SCREEN STENCILLING MACHINE: A FRAME; A STOCKSUPPORTING CYLINDR MOUNTED ON THE FRAME FOR ROTARY MOVEMENT; A SCREEN STENCIL MOUNTED ON THE FRAME ADJACENT THE CYLINDER FOR RECIPROCATING MOVEMENTS LONGITUDINALLY OF THE MACHINE THROUGH PRINT AND NON-PRINT STROKES OF THE MACHINE; A SQUEEGEE MOUNTED ON THE FRAME FOR VERTICAL RECIPROCATION BETWEEN AN INOPERATIVE HIGHLIFT POSITION, AN INTERMEDIATE ELEVATED POSITION OFF THE SCREEN, AND A LOWERED POSITION ONTO THE SCREEN FOR FORCING COATING MATERIAL THROUGH THE STENCIL AND ONTO STOCK SUPPORTED BY SAID CYLINDER; A FLOW COATER MOUNTED ON THE FRAME FOR VERTICAL RECIPROCATION BETWEEN A LOWERED POSITION FOR COLLECTING COATING MATERIAL FROM THE SCREEN STENCIL, AN INTERMEDIATE ELEVATED POSITION FOR DISTRIBUTING COATING MATERIAL OVER THE SURFACE OF THE SCREEN STENCIL, AND AN INOPERATIVE HIGH-LIFT POSITION; FIRST MEANS FOR OPPOSITELY VERTICALLY RECIPROCATING SAID SQUEEGEE AND FLOW COATER IN COORDINATION WITH THE HORIZONTAL RECIPROCATION OF THE STENCIL DURING NORMAL OPERATION OF THE MACHINE SO THAT DURING THE PRINT STROKE OF THE MACHINE THE SQUEEGEE IS IN LOWERED POSITION WHILE THE FLOW COATER IS IN INTERMEDIATE ELEVATED POSITION AND SO THAT DURING THE NONPRINT STROKE OF THE MACHINE THE SQUEEGEE IS IN INTERMEDIATE ELEVATED POSITION WHILE THE FLOW COATER IS IN LOWERED POSITION, SAID FIRST MEANS COMPRISING LEVERS MOUNTED FOR RECIPROCATING ROTARY MOVEMENTS AT OPPOSITE SIDES OF THE MACHINE AND ADAPTED TO BEAR AT THEIR OUTER ENDS AGAINST THE LOWER ENDS OF THE SQUEEGEE BARS FOR VERTICALLY RECIPROCATING MOVEMENTS AT OPPOSITE SIDES OF THE MACHINE, EACH OF SAID LINKS HAVING ONE END THEREOF PIVOTALLY CONNECTED TO ONE OF SAID LEVERS BETWEEN SAID LEVER''S PIVOTAL CONNECTION TO THE FRAME AND SAID LEVER''S END ADAPTED TO BEAR AGAINST THE ADJACENT SQUEEGEE BAR, AND EACH LINK HAVING ITS END OPPOSITE ITS PIVOTAL CONNECTION TO SAID LEVER PIVOTALLY CONNECTED TO THE LOWER END OF THE ADJACENT FLOW COATER ROD, AND MEANS FOR RECIPROCATING SAID LEVERS IN COORDINATION WITH THE HORIZONTAL RECIPROCATION OF THE STENCIL; AND SECOND MEANS FOR SIMULTANEOUSLY ELEVATING BOTH THE SQUEEGEE AND THE FLOW COATER TO THEIR INOPERATIVE HIGH-LIFT POSITIONS.