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Publication numberUS3138095 A
Publication typeGrant
Publication dateJun 23, 1964
Filing dateOct 27, 1960
Priority dateOct 27, 1960
Publication numberUS 3138095 A, US 3138095A, US-A-3138095, US3138095 A, US3138095A
InventorsWells Willis L
Original AssigneeCommander Engineering And Mfg
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Silk screen printing press
US 3138095 A
Abstract  available in
Images(14)
Previous page
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Claims  available in
Description  (OCR text may contain errors)

June 23, 1964 w. WELLS 3,138,095

SILK SCREEN PR1NT1NG PRESS Filed oct. 27. 1960 14 sheets-Sheet 1 FIG. 34

INVENTOR WILLIS L. WELLS M TNO/ @wv Ab AT ORNE S FIG. I

June 23, 1964 w. WELLS 3,138,095

SILK SCREEN PRINTING PRESS Filed Oct. 27. 1960 14 Sheets-Sheet 2 0 0 o o O D I IO' O O O lo l I I l I l I 'o I I l l l o INVENTOR FIG- 2 wsLLls L. wELLs ATTORNEYS June 23, 1964 w. l.. WELLS 3,138,095

SILK SCREEN PRINTING PRESS Filed Oct. 27, 1960 14 Sheets-Sheet 5 7 32o 294 29e 297 y INVENTOR WILLIS L. WELLS FIG. 4

ATTORNE June 23, 1964 w. L. WELLS 3,138,095

SILK SCREEN PRINTING PRESS Filed Oct. 27, 1960 14 Sheets-Sheet 4 "En Hemus FIG. 7 375 39| 389 374 3 7T 4oz 335 336 380 372 FIG. 8

405 j 364 f f -J'4o3/ 404 INVENTOR 41e '-370 w|LL|s L. wELLs ATTORNEYS June 23, 1964 w. L. WELLS 3,138,095

SILK SCREEN PRINTING PRESS Filed Oct. 27, 1960 14 Sheets-Sheet 5 37| FIG. IO 40' |691. O G |49 o 'A FGl Il' l d', LM,

AT ORNEY June 23, 1964 w. WELLS SILK SCREEN PRINTING PRESS 14 Sheets-Sheet 6 Filed Oct. 27, 1960 INVENTOR WILLIS L. WELLS 27# 5ML l A TORNEI/s June 23, 1964 w. L. WELLS SILK SCREEN PRINTING PRESS 14 Shee'cS-Sheet 7 Filed Oct. 27, 1960 INVENTOR WILLIS L. WELLS AT ORNEYS June 23, 1964 w. WELLS SILK SCREEN PRINTING PRESS 14 Sheets-Sheet 8 Filed OOC. 27. 1960 INVENTOR WELLS ATTORNEYS WILLIS L.

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SILK SCREEN PRINTING PREss Filed oct. 27, 19Go I4 sheets-sheet 9 INVENTOR WILLIS L. WELLS BY wf AT RNEY June 23, 1964 w. L. WELLS SILK SCREEN PRINTING PRESS 14 Sheets-Sheet lO Filed OC. 27, 1960 .VN Q-.w w S (/S wm Rm f n Ro E mE m im? w w m V l o SN wm L m L m m2 2 IL im@ IWL L om nu HL hoo m; l o W I I I I I II III IIIIIIII Y W L B u m9| fm T1# @2L Il.:N om i# L2 N@ im@ u om: oom um 1.0i, Tm

June 23, 1964 w. l.. WELLS SILK SCREEN PRINTING PRESS 14 Sheets-Sheet 11 Filed Oct. 27. 1960 INVENTOR WILLIS L. WELLS 10j/41 f A TORNYS June 23, 1964 w. L. WELLS 3,138,095

SILK SCREEN PRINTING PRESS Filed Oct. 27, 1960 14 Sheets-Sheet l2 mmm mmm mi 31 mi E1 ATTORNEYS June 23, 1964 w. L. WELLS 3,138,095

SILK SCREEN PRINTING PRESS Filed Oct. 27. 1960 14 Sheets-Sheet 13 ZQJ FIG. 28

FIG. 29

INVENTOR WILLIS L. WELLS ATTORNEYS June 23, 1964 w. WELLS 3.138.095

SILK SCREEN PRINTING PRESS Filed Oct. 27. 1960 I 14 Sheets-Sheet 14 73 w 73 72 I 72 I I I `I t l `t I Tf74 I L I I FIG. 30 I I k I I 'OB` /IOB |03` |o4 III IIZ II4 |I7 89 ||5 H9A IIS H8 WILLIS L. WELLS ATTORNEYS United States Patent 3,138,095 SLK SCREEN PRINTING PRESS Willis L. Wells, Clayton, Mo., assignor to Commander Engineering and Manufacturing Company, St. Louis, Mo., a corporation of Missouri Filed ct. 27, '1960, Ser. No. 65,347 Claims. (Cl. IUI-123) This invention relates to a silk screen printing press. The machine is the type that can be used for printing such materials as electronic circuits, ceramics, plastics, textiles, metals, or woods and papers.

The art of silk screen printing presses is well known. Basic to it is the provision of a table of platen having a at surface for supporting blank material. With the blank material upon the table,-a stencil, commonly called a silk screen, is placed over the blank. Ink is then forced through openings in the screen to produce the printing operation.

While originally the printing was performed almost entirely by hand, modern development has produced machines that automatically lift the screen between each printing operation for rapid duplication. The machine of the present invention goes beyond those of the prior art in providing completely automatic and entirely ilexible apparatus for silk screen printing.

Another important, and highly sought after, objective in the art is'the provision of a machine that spreads ink evenly across the screen and that produces a sharp print by an eifective off-contact operation. The machine herein described includes means for effectively accomplishing that objective. These means include an ink tray adjacent the rear edges of the platen. An ink applying assembly moves under the influence of a unique control system across the screen from front toward rear. At the end of this stroke, an ink roller carried by the assembly rotates within the tray and picks up a uniform lm of ink over its entire peripheral surface. The roller continues to rotate as it is transported above and out of contact with the screen to its forward position from which it begins a printing stroke. Because of the rotation of the roller, the lm of ink adheres to it rather than dripping down upon the screen. Of course, the ink is taken off the roller as the ink contacts the screen.

The machine is further characterized by extreme versatility and ease of use which are additional objects of the invention. For example, the roller that is carried by the ink applying assembly can be adjusted vertically. Following the ink roller, and attached to the assembly, is a squeegee for applying such pressure to the top of the screen that ink is forced through. The squeegee also wipes the surplus of ink from the top of the screen above the blank that is being printed. The squeegee can be adjusted verticallyvin height relative to thel height of the roller, and it can be tilted from side to side. In addition, the angle of incidence or approach of the squeegee can be adjusted.

The ink applying assembly is supported adjacent the top of a frame housing and, in addition to the appropriate power source for reciprocating the assembly horizontally, there is a guide means in the form of a cam that determines the path of movement of the assembly as it is reciprocated. An important feature of the cam guide means is the fact that it moves the assembly along a substantially horizontal plane during the printing stroke of the assembly. In the other direction of movement of the assembly, the cam first raises the assembly, and with it the roller and squeegee, to separate it from the blank material being printed. The assembly is then guided by an elevated path over the top of the cam guide means to its position for repeating the printing stroke.

Another object of the invention, therefore, is to provide 3,138,095 Patented June 23., 1964 a silk screen printing press with a control system for assuring the even distribution of ink over the screen.

The ink roller that is carried by the assembly is powered by a motor contained within the movable assembly. The cord line that supplies power to the motor must, necessarily, pass through the machine. In order to prevent interference by the cord means in the reciprocation of the assembly, there is a spring tension element about which the cord is wound for maintaining a generally constant tension on the cord, regardless of the position of the ink applying assembly. This assurance that the cord will not interfere with the operation of the machine is another object of the invention.

Still another object is to provide in the control mechanism for the printing machine a system of automatic stop means. The stop means will stop and start the assembly at exactly the same position during each printing cycle. A feature of the stop and start means is the fact that the stopping position of the ink applying assembly can be adjusted. Likewise, the duration of pause between stop and restart can be adjusted.

The machine has a table or platen for supporting a blank upon which the printing operation is to take place. The table is attached to the frame below the ink applying assembly. There is a screen that is separately and pivotally attached to the frame. Thus, the height of the table can be adjusted relative to the screen to obtain any desired degree of off-contact printing. Because the squeegee is separately adjustable in height, it can be positioned to press the adjacent part of the screen against a blank on the table while forcing ink through that part of the screen. Since the screen is tight, the rest of it will tend to remain separated from the table. Nevertheless, the roller need not contact the screen because it, also, is separately adjustable in height.

The screen is of a general type that is used in conventional silk screen printing presses except that it is operated in a novel manner in direct relation to the motion of the ink applying assembly. In this regard, there is a connection between the ink applying assembly and the screen that operates automatically to pivot the screen during movement of the ink applying assembly. The screen is raised or pivoted away from the table when the ink applying Vassembly is raised by the sprocket chain and the cam guide means, and the screen is lowered upon movement of the ink applying assembly back to its lowermost plane of horizontal movement.

Accordingly, another object of the invention is to provide a printing machine with a screen that is controlled to print relative to the table by the ink applying assembly.

In certain instances, it is desired that more than one printing run be made. The present machine incorporates a screen lock for holding the screen against the table during the otherwise normal operating cycle. Therefore, successive printing passes can be made with the assurance that each printing stroke will occur with the screen in a single set posi-tion.

There lis another extremely important object of the invention, and that is the provision of a machine that can be made Vto skip print even though the ink applying assembly continues to cycle. The skip print is accomplished by a lever mechanism that pivots the upper part of the frame housing, carrying with it the ink applying assembly away from the table. Thus, upon operation of the lever, the blank material on the table can be handled or adjusted even though the ink applying assembly continues to reciprocate.

Still another object is to provide a blank supporting table for a printing machine that is Vfully adjustable. There are a plurality of vertically spaced points on the frame housing to which the table can be attached according to the approximate height at which it is to be used. In addition, there is a line adjustment in the form of a wheel beneath the table for making critical height adjustments of the table. (Also, as already mentioned, the heights of the roller and squeegee can be separately adjusted.) The position of the table can be adjusted from side to side, fore and aft, and its angle can be varied by pivoting it about a vertical axis.

Other objects are to provide a silk screen printing press having a roller for spreading ink and which is readily removable for ease of cleaning and for replacement in a variety of lengths.

Yet another object of the invention is the` provision of a printing press than can print with a plurality of colors Iin a single operation. Because the machine is provided with stationary tray means for holding the ink and with removable roller means for spreading the ink, the tray means can be divided into a plurality of compartments, side by side, each containing a different color of ink; and the roller means can comprise a plurality of adjoining roller surfaces with suicient space between them for receiving the tray partitions.

A further object of the invention is to provide a silk screen printing machine characterized by extreme ruggedness and rigidity. All of the action of the machine is accomplished with positive mechanisms journaled in lifetime bearings.

A still further object of the invention is to provide a printing machine with a table subjected to a vacuum with valve means between the vacuum source and the table controlled by the raising and lowering of the screen.

Yet another object of the invention is to provide a silk screen printing press having an ink roller and squeegee that is moved past the Screen with a pause time at the end of the ink spreading stroke, the velocity of movement" and the duration of pause time being independently variable.

In the drawings:

FIGURE 1 is a front elevation View of the silk screen printing press;

FIGURE 2 is a side elevation view of the printing press taken from the right side of FIGURE l, but with parts broken away to show the vacuum connection and the actutaing means for controlling the activation of the vacuum means;

FIGURE 3 is a plan View of the ink applying assembly removed from the machine. The scale of FIGURE 3 is somewhat greater than that of FIGURES 1 and 2;

FIGURE 4 is a front elevation view of the ink applying assembly on an enlarged scale with certain other parts appropriate to the ink applying assembly being shown in section;

FIGURE 5 is a side elevation view of the ink applying assembly as removed from the machine, taken from the right side of FIGURE 4;

FIGURE 6 is an enlarged isometric detail of the manner in which the sprocket chain that drives the ink applying assembly is connected to that assembly;

FIGURE 7 is a view in section taken along the line 7-7 of FIGURE 3. The scale of FIGURE 7 is greater than that of FIGURE 3;

FIGURE 8 is a view in section similar to that of FIG- URE 7, but on a reduced scale with parts broken away and showing the attachment of the squeegee;

FIGURE 9 is a rear elevation view of the lower part of the ink applying assembly. The ligure is on an enlarged scale;

FIGUREV 10 is a view in section taken along the line 10--10 of FIGURE 5, but on an enlarged scale;

FIGURE 11 is an isometric detail, partly in section, showing the way in which the roller is applied to the assembly;

FIGURE 12 is a plan view of the printing press with the top panels removed to show details of the interior;

FIGURE 13 is a view in section taken along the line 1 3--13 o f FIGURE 12;

FIGURE 14 is a view in section taken along the line 14-14 of FIGURE 13;

FIGURE 15 is a view in section taken along the line 15-15 of FIGURE 12;

FIGURE 16 is a view in section taken along the line 16-16 of FIGURE 15;

FIGURE 17 is a partial view in section taken along the line 17-17 of FIGURE 12;

FIGURE 18 is an isometric detail of the mechanism for lowering the screen prior to the printing stroke of the machine;

FIGURE 19 is a view in section taken along4 the line 19-19 of FIGURE 12;

FIGURE 20 is a view in section taken along the line Ztl-20 of FIGURE 17;

FIGURE 21 is a view in section taken along the line 21-21 of FIGURE 20;

FIGURE 22 is a view in section taken along the line 22-22 of FIGURE 20;

FIGURE 23 is a view in section taken along the line 23-23 of FIGURE 20;

FIGURE 24 is a partial view in section taken along the line 24-24 of FIGURE 20;

FIGURE 25 is an isometric view, partly in section, of certain details of the skip print mechanism;

FIGURE 26 is an isometric exploded view of certain elements of FIGURE 25;

FIGURE 27 is a partial view showing the operating mechanism for locking the screen against the table;

FIGURE 28 is a front elevation view of the table showing the adjusting mechanism;

FIGURE 29 is a view in section taken along the line 29-29 of FIGURE 28;

FIGURE 30 is a view in section taken along the line 30--30 of FIGURE 28;

FIGURE 31 is a partial View in section taken along the line 31-31 OFIGURE 28;

FIGURE 32 is a partial view in section taken along the line 32-32 of FIGURE 29;

FIGURE 33 is a View in section taken along the line 33-33 of FIGURE 2s;

FIGURE 34 is a partial plan view on enlarged scale of the table with parts broken away to show the vacuum paths;

FIGURE 35 is a view 35-35 of FIGURE 34;

FIGURE 36 is a view in section taken along the line 36--36 of FIGURE 35; and

FIGURE 37 is a front elevation view of the machine omitting the upper part thereof and with the lower portion of the table broken away to show details of the vacuum mechanism and connections.

In the description to follow, themachine is considered to have a front, a rear, and left and right sides. These may be determined by reference to FIGURE 1 which shows the front. The left and right sides are as viewed in FIGURE 1.

in section taken along the line The Table Assembly Referring particularly to FIGUREZ, the housing or frame of the machine is comprised of two sections, a bottom section 51 and a top section 52. The bottom section 51 includes a base 53 that stands on individually adjustable feet 54. Upwardly, depending from the base 53, the bottom section S1 includes a front wall 55, left and right side walls 56 and 57, respectively, and a rear wall 58. The part near the top of the lower section 51 is appropriately anged as at 59 and 60 to support upper side panels 61 and 62 that are bolted to the anges 59 and 60` and front and rear panels 63 and 64 that are welded to the side panels 61 and 62 that are bolted to the anges 59 and 60 and front and rear panels 63 and 64 that are welded to the sidevpanels 61 and 62. The upper front panel 63 is spaced from the forward ends of the side panels 61 and 62 as can be seen in FIGURE 20.

The front panel of the bottom Section5() has two parallel rows of vertically aligned tapped holes 70. A table assembly 71 is mounted by bolts 72 to upper ones of the holes 70. Other of the holes 70 may be used for supporting the table according to the height at which it 1S to be mounted. The bolts 72 fasten through flanges 73 of a large casting '74, the shape of which can be best appreciated from FIGURES l, 2, 28, 29 and 30.

The casting 74 is for supporting a table as will be described, and for this purpose the central forward part of the casting 74 is formed with a vertical internal cylinder 75 having kerfs 76 spaced along its inside wall. The bottom 77 of the cylinder 75 is closed except for a hole 7S through its center.

Toward each side of the cylindrical part 75 of the casting 74, and toward the top of the casting 74 are thickened or reinforced corners 80 and 81, and each of the thickened corners 30 and 51 is bored through from front to rear at 82 and S3, respectively. The cylinder 75 is for axially centering a table supporting cylinder, and the bores 82 and S3 are for receiving certain mechanism for pivoting the table about a vertical axis through the center of the cylinder 75. All of this will follow in detail.

The table supporting cylinder 85, before mentioned, lits slidably within the internal cylinder 75. It also can rotate within the cylinder 75. The bottom 36 of the cylinder S5 is closed, except for a threaded hole S7 ythrough the center of the bottom 86.

An elongated screw 88 is threaded into the hole 87. The screw S8 passes through the hole 78 in the bottom 77 of the cylinder 75 and has a turning wheel 89 iixed by a pin 90 to its lower end. There is a washer 91 that prevents the downward movement of the screw 8S.

As can be seen in FIGURE 29, the cylinder 85 is raised and lowered by rotation of the wheel S9, which rotates the screw S8, the threads of which mesh with the threads of the hole 37.

Because the table is adjustable in all directions, and because it must be perfectly steady once it has been adjusted, there are a number of different parts between the table and the cylinder 85. The first of these, to which the cylinder 85 is bolted, is a casting 93, the top 94 of which ts flush with the cylinder 85. The casting 93 has forwardly extending wings 95 at each side of it, and similar rearwardly extending wings 96. There are coaxial holes 97 through the wings 95 and co-axial holes 98 through the wings 96.

The mechanism for pivoting the casting 93, with the cylinder 85, about the axis of the cylinder 75 includes a pair of levers 100 and 101 bolted to the under surface of the casting 93 toward the sides. The levers 100 and 101 project downwardly fromv the casting 93 through holes 102 in the casting 74. The location of the lever arms 100 and 101 and the holes 102 is such that the lower ends of the levers 100 and 101 are positioned adjacent the bores 82 and 83 through the corners 80 and 81 of the casting 74.

There are a pair of cylindrically shaped blocks 103 and '104 slidably disposed within the bores S2 and 83, respectively. Each of the cylindrical blocks 103 and 104 has 'a pair of vertically aligned slots 105 and 106 through it,

and there are a pair of pins 107 xed to each of the corners 30 and 81 of the casting 74. The slots 105 and A106 cooperate with the pins 107, to define the limits of vmovement of the cylindrical blocks 103 and 104.

The inner end of each block 103 and 104 has spaced apart ears 108. There is a pin 109 fixed between each set of ears S for rotatably supporting a pair of rollers 110. .The rollers 110 are each intended to bear against one of the levers 100 and 101. Both rollers can be used to control the positions of the levers 100 and 101.

There are small plates 111 and 112 fastened by bolts 113 across the forward ends of the bores 82 and 83, respectively. Threaded through the plates 111 and 112 are a pair of screws 114 and 115, respectively. The screw 114 has a handle 116 on its end and a lock nut 117 to x 6 it in position. There is a similar handle 118 and lock nut 119 for the screw 115.

As will be apparent from FIGURES 30 and 31, the casting 93 can be rotated relative to the casting 74 upon positioning the rollers against the lever arms 100 and 101. Thus, if the handle 116 is turned clockwise and the handle 118 counterclockwise, the casting 93 will be caused to rotate in a clockwise direction, as viewed in FIGURE 30. Because of the special adaptability of the printing press to off-contact printing, the table may often be adjusted in height, particularly to move it away from the screen surface. This adjustment that is accomplished by turning the handwheel 89 is useful particularly upon a change of blanks upon the table, which blanks may be of various thicknesses. Such height adjustment is accomplished without friction against the lever arms 100 and 101 because of the rollers 110.

The means for raising and lowering the table and for pivoting it has been described. There is also movementy from side to side and fore and aft. For the side to side movement, there is a cast plate 122, the shape of which can be seen in FIGURES 28, 29, 31, 32 and 33. There are cuts 123 through the corners of the casting 122 to allow space for the wings 95 of the casting 93 that project upwardly therefrom. Fixedly secured between the sides of the cast plate 122 by studs 124 are a pair of bars 125. The bars 125 pass through the holes 97 and 98 in the wings 95 and 96 of the casting 93. The bars 125 iix the position of the cast plate 122 relative to the casting 93 while permitting it to slide from side to side.

There are a pair of tapped holes 126 and 127 through the sides of the cast plate 122 into which are threaded a pair of screws 128 and 129, respectively. The inner ends of the screws 128 and 129 bear against the sides of the casting 93. For the screw 123 there is a handle 130 and a lock nut 131. There is a handle 132 and a lock nut 133 for the screw 129. The cast plate 122 is shifted from side to side merely by operation of the handles and 132. After it is positioned, the lock nuts 131 and 132 are tightened.

The cast plate 122 has front and rear walls 135 and v136, respectively, each having raised bosses 137 adjacent the sides of the plate 122. There are holes 133 through the bosses 137. Opposing ones of the front and rear holes 138 are coaxial.

u To provide fore and aft movement of the table, there 1s a cast frame 140, as illustrated in FIGURES 28, 29, 31, 32 and 33. There are a pair of bars 141 that are fixed to holes 142 in forward and rearward bosses 143 of the frame by studs 144. The bars 141 each pass through a pair of the holes 138 in the cast plate 122, as shown in FIGURE 33.

The forward side of the cast frame 140 has a central .thickened portion 146 with a tapped hole 147 through 1t. There is a screw 148 that is threaded through the hole 147 with its free end bearing against the forward side of the cast plate 122. The screw 148 has a handle .149 for turning it and a lock nut 150 for locking it.

In the rearward side of the cast frame 140 is another central boss 151 having a tapped hole 152 through it. There is a screw 153 threaded through the tapped hole .152 having a handle 154 and a lock nut 155.

The cast frame 140is moved forwardly or rearwardly by turning the handles 149 and 154. Obviously, one ,of the handles must be loosened if the other is to be turned in a clockwise direction.

Operation of the Table Assembly .fis possible. There is approximate vertical positioning of the table according to which ones of the holes 70 the table assembly is attached. There is micrometer adjustment in a vertical .direction upon rotation of the 7 handwheel 89. Such rotation raises the cylindrical casting 85, as well as the castings 93, 122 and 140, and the table 158.

There is adjustment from side to side upon rotation of the handles and 132. These handles tix the position of the casting 122 (and with it the casting 140 and the table 158) relative to the casting 93 (and the principal frame 50 of the machine). The position of the table fore and aft can be selectively xed by rotation of the handles 149 and 154. The screws 148 and 153 connected to these handles position the cast frame and the table relative to the casting 122. And, nally, the table can be rotated by rotating the handles 116 and 118. The pressure of the screws 114 and 115 against the levers 100 and 101 determines the angular position of the cylindrical casting 85 relative to the casting 74.

T he Vacuum System The table 158 is made up of three layers 160, 161

and 162 that are Welded on top of one another in the order named. The middle section 161 comprises a large number of formica strips 163 so arranged on the plate 160 as to form interconnected air passages 164. In addition, the middle layer 161 has a border 165 formed by formica plates that entirely enclose the air passages 164. The top plate 162 completely covers the air passages 164 but has a plurality of small vacuum holes 166 through it in communication with the passages 164.

An air hose connection 168 is fastened through the lower plate 160 of the table 158, and communicates with the interconnected air passages 164. There is a similar air hose connection 169 at the opposite end of the table. The connections 168 and 169 pass through hoses 170 and 171, respectively, to a T-itting 172 that in turn is connected to a hose 173, These connections are shown in FIGURE 37. The hose 173 is connected to a valve 174 of the type that is lever operated to be opened and closed, as will be described.

From the valve 174, there is a hose connection 175 to a vacuum power source 176 which is illustrated as being in the form of a conventional vacuum cleaner. The vacuum power source is suitably secured to the base 53 by clamps 177. The purpose of the vacuum' connection to the table 158 is to hold the blank material to the table. When the material is placed upon the table, it covers the holes 166 so that the vacuum can be eiectively created by the power source 176. The vacuum will hold the material to the table even while the latter is being adjusted into one of its many possible positions.

Mounting of the Screen Frame Holder A screen frame holder 180 is pivotally attached between the upper side plates 61 and 62 of the bottom section of the frame. The screen frame holder need not be described in detail, inasmuch as its typical structure may be varied considerably and is generally conventional to the art. It should, however, be noted that the screen frame holder includes form plates 181, 182, 183 and 184, fastened by quickly releasable bolts 185 to the frame holder 180. These plates releasably secure a screen frame 186 (shown in dotted lines in FIG- URE 21) in such a way that the screen frame can be readily replaced upon loosening of the four bolts 185.

What is important to the invention is the way that the screen frame holder 180. is connected to and controlled by the machine in synchronization with other of the operating elements. The supporting structure for the screen frame holder 180 includes two upstanding brackets 190 and 191 welded respectively to the side panels 61 and 62. Journaled in holes 192 and 193 that are formed through the brackets 190 and 191 is a bar 194. The bar 194 can rotate within the holes 192 and 193.

Fastened to the rearward undersurface of the frame 180 by clamps195 andr196 is a plate 197 to which are screwed a pair of brackets 198 and 199. Each of the brackets 198 and 199 is formed of two pieces 200 and 201 fastened together in an elbow shape, as illustrated in FIGURE 19.

The forward end of the lower plate 201 of each bracket 198 and 199 has a hole 202 through it that receives the bar 194, and each of the brackets 198 and 199 is welded to the bar 194 adjacent to and inside of its respective bracket 190 and 191 to limit axial shifting of the bar 194.

Rearward is another bar 203 that is welded to the brackets 198 and 199. Various levers are welded to the bar 283 for pivoting the screen about the bar 194, and these levers will be described hereafter in detail, along with their operating mechanism.

The Ink Applying Assembly Reference has been made to the top section 52 of the frame 50. The top section 52 has a lower frame 210 comprising a front panel 211, a rear panel 212 with a removable access plate 213, and side panels 214 and 215. As can be seen in FIGURE 20 of the drawings, the crosssectional size of the front, rear, and side panels just identitied, is such that the upper frame section 52 can fit within the space defined by the panels 61, 62, 63 and 64 of the bottom frame section 51. In addition, referring to FIGS. 19 and 23, it can be seen that there are opposed pins 216 and 217 fastened by nuts 218, together with appropriate bushings 219, to side frame members 61 and 62 of the bottom section 51. These pins 216 and 217 are journaled within holes 220 and 221 that are in reinforcing bars 222 and 223 respectively. The reinforcing bars 222 and 223 are positioned near the forward edges of the side panels 214 and 215, respectively, and are welded in place.

Welded to the top of the bars 222 and 223, and to the top edges of the front panel 211, rear panel 212, and side panels 214 and 215, is a top panel 224. Welded to the forward corners of the top panel 224, and to the upper sides of the bars 222 and 223, respectively, are a pair of bearing blocks 225 and 226.

The top frame section 52 has an upper part 229 that includes a bottom panel 230 superposed upon and bolted to the panel 224. The panel 230 extends beyond the panel 211 and terminates in a front edge 231. It should be here noted that there are holes 232 and 233 through the panels 224 and 230 to allow for various operating mechanisms that will be described. In addition, there are smaller holes 235 that pass through the blocks 225 and 226, respectively, and through the panels 224 and 230.

There are side panels 236 and 237 projecting upwardly from the panel 230, and set inwardly from the side edges of the panel 230. The side panels 236 and 237 are welded to angle irons 238 and 239, respectively, that are in turn welded to the panel 230 adjacent the sides of the hole 233. The side panels 236 and 237 and the angle iron bars 238 and 239 extend a considerable distance forward of the edge 231 of the panel 230, as shown in FIG- URE 19. There is a top panel 240 between the upper edges of the side panels 236 and 237, and including removable access panels 241 and 242. There is also a rear panel 243 and a front panel 244. Between the front panel 244 and the top panel 241, there is a sloping panel 245 having a vertical slot 246 in it. The slot 246 accommodates the operating lever for a skip print mechanism that will be described.

There are side wings 247 and 248 for the frame. The side wing 247 includes a side panel 249, a front panel 250, and a rear panel 251. There is an angle iron frame 252 welded to the panels 236, 249, 250 and 251, and a removable top panel 253 is bolted to the angle iron frame 252.

The right side wing frame 248 has a side panel 254 and front and rear panels 255 and 256, respectively, with an angle iron frame 257 supporting a removable top panel 258.

There is an ink applying assembly 264 that is mounted to reciprocate horizontally and vertically in the upper frame section 52. The guide mechanism for the ink applying assembly includes a pair of angle iron members 265 mounted parallel to and above the angle iron bars 238 and 239. The angle iron members 265 are welded to the panels 236 and 237. A pair of horizontal tracks 266 with both upper and lower limits are thus dened between the angle members 238 and 239 and the angle members 265.

Mounted above the tracks 266, and spaced toward the side panel 237 is a cam plate 267. The cam plate 267 is welded to appropriate spacers 268, 269 and 270, that are in turn fastened by bolts 271 to the side panel 237. The shape of the cam plate 267 is important, and as can be seen in FIGURE 19, the lower surface 272 between the points 273 and 274 is straight and horizontal. From the point 274, the cam plate 267 arcs upwardly to the point 275, from which point there begins a gradual and uniform ascent 276 to the point 277. Between the points 277 and 278, there is a straight horizontal surface 279. From the point 278, the cam 267 defines a surface 280 that is semi-circular to the point 273.

The ink applying assembly 264 includes a carriage 285 that is cast with a pair of downwardly depending sleeves 286 and 287. The sleeves 286 and 287 are bored through at 288 and 289, respectively. The upper end of the bore 288 is lined with a bushing 290, the lower end with a bushing 291 and the lower end of the bore 289 with a bushing 292.

The left side of the carriage 285 has forward and rearward extensions 293 and 294, and the right side of the carriage 285 has forward and rearward extensions 295 and 296. Bolted to the extensions 293 and 294 are a pair of wheels 297. Similar wheels 298 are bolted to the extensions 295 and 296. The wheels 297 are adapted to ride along the track 238 and the wheels 298 are adapted to ride within the track 239.

To guide the carriage 285 laterally, there are a pair of wheels 299 bolted to the left side of the carriage 285 beneath and inward of the wheels 297. The wheels 299 have a vertical axis of rotation. There are similar wheels 300 having vertical axes of rotation adjacent the wheels 298. As can be seen in FIGURE 4, the wheels 299 and 300 are adjacent the channel members 238 and 239 to limit the movement of the carriage 285 laterally between the channel members.

Between the sleeves 286 and 287 of the carriage is a space 301. There is a vertical hole 302 through the carriage 285 above the space 301 with a resilient washer or buffer 303 resting upon the carriage above the hole 302.

A cam follower housing 307 is carried by the carriage 285. The cam follower housing 307 includes a pair of tubes 308 and 309 positioned to reciprocate within the bores 288 and 289, respectively. The upper ends 310 and 311 of the tubes 308 and 309, respectively, are reduced in cross-section and are presst into suitable holes in a cam follower block 312. They may be welded thereto.

There is a roller cam follower 313 that is bolted to the right side of the follower support 312. The roller 313 is adapted to follow the contour of the cam plate 267 to cause the ink applying assembly to reciprocate in a vertical direction. The cam follower 313 is held from moving laterally away from the cam plates 267 by the angle members that dene the tracks 266 and by the rollers 299 and 300.

It will be noted from FIGURES 3 and 7 that the rear portion of the tube 309 is cut away at 315 near its top. In addition, there is a slot 316 in the rear part of the cam follower block 312 and above the cutout 315. To the wings 317 and 318 on either sides of the slots 316 is mounted a pulley 320. The pulley 320 is for guidin a power cord.

At the lower end of the tubes 308 and 309, there is a plate 323 having holes 324 and 325 for fitting over the tubes 308 and 309. In addition, there is a hole 326 through the center of the plate 323. The plate 323 is welded to the tubes 308 and 309.

The lower ends 327 and 328 of the tubes 308 and 309, respectively, are reduced in size below the plate 323. There is a casting 330 having a top 331 with holes 332 and 333 for fitting onto the ends 327 and 328 of the tubes 308 and 309. The casting 330 is bolted in place, as illustrated in FIGURES 7 and 9. The casting 330 also has a hole 334 contiguous with the hole 326.

The casting 330 has a hollow interior and a lower front part 335 that projects forwardly. The top of the front part 335 has a slot 336 through it. One either side of the front part 335, there are downwardly depending flanges 337. Each of the flanges 337 has a hole 338 through it. From the rear of the front extension 335, and the rear of the slot 336, the casting 330 has an upwardly sloping front wall 339.

There is a squeegee frame 342 having Vertical arms 343 and 344 connected by pins 345 to pivot about the holes 338 in the casting 330. A middle horizontal arm 346 connects the span between the upper ends of the arms 343 and 344, and there are rearwardly bent wings 347 and 348 depending outwardly from the arms 343 and 344, respectively.

There are handles 349 and 350 that are free to rotate within the ends of the wings 347 and 348, respectively, but they are restricted against vertical movement relative thereto. Integral with and depending downwardly from the handles 349 and 350 are screws 351 and 352, respectively.

There are a pair of squeegee mounts 353 and 354 with lock nuts 355 and 356 adjacent to their tops. The squeegee mounts 353 and 354 are hollow, and the screws 351 and 352 are threaded through the amounts 353 and 354, and can extend as far as necessary within the mounts 353 and 354. A conventional squeegee 357 of rubber or the like is clamped by thumb screws 358 between ears 359 at the lower ends of the mounts 353and 354. The squeegee 357 is readily replaceable by simple rotation of the thumb screws 358.

The squeegee 357 can be raised and lowered by rotation of the handles 349 and 350. In addition, the squeegee 357 can be tilted at an angle to the table if the handles 349 and 350 are turned by different amounts, if concentrated or uneven pressure is desired.

At the center of the metal bar 346 of the frame 342, there is a downwardly depending tab 360. There is a relatively long bolt 361 threaded through the bar 346 with its end bearing against the front 339 of the casting 330. There is a handle 362 for rotating the bolt 361. Immediately below the bolt 361 is another bolt 363 that is threaded through a tapped hole 364 in the front of the forward section 335 of the casting 330. The end of the bolt 363 bears against the tab 360 that is integral with the bar 346. There is a handle 365 for rotating the bolt 363.

By means of the handles 362 and 365, which are accessible from the exterior forward side of the ink applying assembly, the angle of incidence of the squeegee 357 can be adjusted. This can be done with positive stops because the bolt 361 limits the pivotal movement of the squeegee 357 in one direction and the bolt 363 limits that movement in the opposite direction.

There is a roller conveyor assembly 370 that is carried by the carriage 285 and the cam follower housing 307.

lThe roller conveyor housing or assembly includes a mounting plate 371 to which are attached certain supporting means. To this end the mounting plate 371 has a hole 372 through it. There is a sleeve 373 having a reduced end 374 that is presst into the hole 372 and Welded. The sleeve 373 is hollow bored and has internal threads 375. A jamb nut 376 is provided.

There is a long bolt 377 having a washer 378 welded to its top that is passed through the hole 302 in the carriage 285 and the hole in the bushing 303, and threaded into the bore 375. The bolt 377 has a turning knob 379 welded to it. There is a cylindrical guide element 380 beyond the lower end of the threads of the bolt 377 for maintaining the bolt 377 coaxial with the bore 375, even when the bolt is only partially threaded into the bore 375. A setscrew 381 through the side of the sleeve 373 is for limiting the upward travel of the bolt 377.

At the forward end of the mounting plate 371, there is a hole 385 for receiving the reduced ends 386 of a shaft 387. There is a piece of angle iron 389 welded to the underside of the plate 371 to support a motor as will appear. The angle iron 389 has a hole 390 through it coaxial with the hole 385. A nut 391 fastens the shaft 387 to the plate 371 and the angle iron 389.

The main section 392 of the shaft 387 is of smaller diameter than the internal diameter of the tube 308. However, at the upper end 393, the diameter of the shaft 387 is increased to almost that of the internal tube span. There is a washer 394 welded to the top of the larger part 393 of the shaft 387.

At the point 395 where the shaft 387 increases in diameter, a spring seat is defined. A compression spring 396 is seated against the seat 395. At the lower end of the tube 308, there is welded a sleeve 397 that acts both as a lower seat for the spring 396 and as a bushing for the shaft 387. The axial position of the shaft 387 is thus continuously guided by the larger part 393 at its upper end and by the sleeve 397. The shaft 387 can reciprocate vertically within the sleeve 308 between the limits defined by the washer 394 and by the plate 371 at the lower end of the tube 308.

For attaching a motor 400 to the roller conveyor assembly 370, there is a plate 401 that is welded to the piece of angle iron 389. The motor 400 is fastened by bolts 402 to the plate 401 and to the angle iron 389. The shaft 403 of the motor 400 projects forwardly and has worm gear 404 fixed to it by setscrews 405.

There is a casting 407 that covers the shaft 403 and the worm gear 404. The casting 407 has internal and horizontal left and right sleeves 408 and 409, respectively. There are slots 410 and 411 through the tops of the sleeves 408 and 409, respectively, so that the sleeves can be tightened by bolts 412. There are a pair of ball bearings 415 tted within the sleeves 408 and 409. The ball bearings 415 provide a rotatable amount for a shaft 416.

A gear 417 that meshes with the worm gear 404 is mounted between the ball bearings 415. The gear 417 is fixed to the shaft 416 by a key 418. There is a washer 419 bolted to the right end of the shaft 416 for-locking the shaft against movement past the right ball bearing 415. There are certain driven connections to the shaft 416 that will be described.

Hollow cylindrical shafts 420 are bolted within the sleeves 408 and 409, respectively. Fixed within` the left hand shaft 420 by a bolt 421 is a sleeve 422. The sleeve 422 projects beyond the end of the tube 420. At the opposite side of the casting 407, there is a sleeve 423 fastened within the right hand shaft 420, by a bolt 424.

There is a casting 425 having a cylindrical extension 426 that is screwed onto the end of the sleeve 42,2.- Below the extension 426 and spaced therefrom, is another extension 427. The internal surface 428 of the extension 426 is cylindrical, and so is the internal surface 429 of the extension 427. There is an end cap 430 that covers the left end of the casting 425.

Opposite the casting 425, there is another casting 431 having a cylindrical extension 432 with a hollow tube 433 pinned within it. The hollow tube 433 slidably extends within the sleeve 423. A knob 434 having a bearing ange 435 for limiting its movement inwardly of the tube 433 has a cylindrical extension 436 that projects within the 12 tube 433. There is a hook 437 on the inner end of the extension 436 for the attachment of a tension spring 438. The opposite end of the tension spring 438 is attached to a pin 439` that is connected to the sleeve 433.

Below the extension 432 of the casting 431, there is another extension 440 with an internal cylindrical surface 441 coaxial with the cylindrical surface 429 of the casting 425. There are a pair of ball bearings 442 fitted within the extension 427, and a similar pair of ball bearings 442 fitted within the extension 440.

There is a shaft 443 journaled to rotate within the ball bearings 441 and having pin elements 444 extending laterally from the sides of the enlarged head 445 on the inner end of a shaft 443.

Iournaled within the bearings 442 there is a shaft 448 with a washer 449 limiting its movement in one direction and an enlarged cylindrical head 450 limiting its movement in the opposite direction. There are pin elements 451 and 452 projecting laterally from the side of the head 450.

There is an ink roller 454 that can rotate with the shafts 443 and 448. Within the left side of the ink roller 454 is a cylindrical block 455 having a recess 456 for receiving the head 445 of the shaft 443 with slots 457 for receiving the pins 444.

A similar block 458 is pressfit within the right side of the ink roller 454. The block 458 has a recess 459 for receiving the head 450 of the shaft 448, and slots 460 for receiving the pins 451 and 452.

There is a driving connection between the shaft 443 and the shaft 416 that includes a spur gear 463 fastened by a bolt 464 to the end of the shaft 443 so as to rotate coaxially therewith. It may be noted that the shaft 443 is locked against longitudinal movement by the spur gear 463 at one end and the head 445 at the other end.

The spur gear 463 meshes with a larger spur gear 465 journaled on a ball bearing that is bolted at 466 to the casting 425 between the extensions 426 and 427. The spur gear 465 in turn meshes with another spur gear 467 that is attached by a bolt 468 to the end of a shaft 469. The shaft 469 is rotatable within ball bearings 470 that are pressitted within the cylindrical surface 428 of the extension 426.

The shaft 469 has an enlarged head 471 of the same diameter as the left end of the shaft 416. There is a cylindrical tube 472 fitted over the end 471 of the shaft 469 and over the left end of the Shaft 416. The tube 472 is fastened by a pin 473 to the shaft 469 and by a pin 474 to the shaft 416.

There is a power cord 477 attached to the motor 400. The cord 477 is drawn through the tube 309 and over the pulley 320. The cord 477 is wrapped about a spring biased pulley 478 that is mounted to the panel 236 of the frame. From there it is connected by means not shown to a source of alternating current.

Operation of the Ink Applying Assembly It can be seen from FIGURE 10 that the roller 454 can be caused to rotate upon energization of the motor 400. The power is transmitted through the motor shaft 403 and the worm gear 404 to the gear 417. The gear 417 transmits its rotational power through the shaft 416 and the tube 472 tothe shaft 469. The spur gear 467 that is attached to the shaft 469 rotates with that shaft and causes the idler gear 465 to rotate. Rotation of the idler gear 465 causes the gear 463, with which it is in mesh, to rotate, and with the gear 463. the shaft 443 rotates. Because the pins 444 project within the slots 457 in the block 455, rotation of the shaft 443 causes the ink roller 454 to rotate.

The opposite end of the ink roller 454 is free to spin because the shaft 448 is rotatable within the roller ball bearings 442.

An important feature of the invention is the ease with which the roller 454 can be cleansed of ink. For this

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1776459 *Mar 5, 1928Sep 23, 1930Western Lithograph CompanyApparatus for making stencil prints
US1781209 *Mar 11, 1929Nov 11, 1930Designograph CompanyDevice for making designs on cakes and the like
US1966416 *May 21, 1932Jul 10, 1934Naz Dar CompanyPrinting machine
US2581775 *Sep 4, 1948Jan 8, 1952Wade Louis RScreen printing machine
US2651988 *Feb 5, 1947Sep 15, 1953Roto Matic Sereen Printer LtdStencil printing apparatus
US2704510 *Jul 5, 1952Mar 22, 1955Eugene LandesmanScreen printing machines
US2729162 *Jun 10, 1953Jan 3, 1956Rauland CorpScreening apparatus
US2730043 *Aug 27, 1951Jan 10, 1956Nathan LouftSqueegees
US2739532 *Dec 9, 1954Mar 27, 1956 fernandez
US2751842 *Jun 8, 1953Jun 26, 1956Marler E T LtdScreen stencil-printing machines
US2887044 *Jun 26, 1956May 19, 1959Smejda Richard KMulticolor inking and application device
US2963964 *Jul 22, 1958Dec 13, 1960Master Screen Printing EquipmeAutomatic silk screen printing machine
US2965021 *Feb 14, 1958Dec 20, 1960Ideal Stencil Machine CompanyStencilling machine
US2966115 *May 4, 1959Dec 27, 1960Speer Carbon CompanyScreen printing apparatus
US2975705 *Feb 12, 1958Mar 21, 1961Louis GilmanSilk screen process press
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3486441 *Apr 14, 1967Dec 30, 1969Mitronics IncSilk screen apparatus for precision coating articles
US4038920 *May 7, 1975Aug 2, 1977Evana Tool & Engineering Inc.Screen positioning and squeegee drive means for screen printer
US4307662 *Jul 31, 1979Dec 29, 1981Mathias MitterApparatus for printing on webs
US4537126 *Oct 26, 1982Aug 27, 1985American Screen Printing Equipment Co.Automatic peel control mechanism
US4747211 *Jun 5, 1987May 31, 1988Sheldahl, Inc.Method and apparatus for preparing conductive screened through holes employing metallic plated polymer thick films
US5582104 *Nov 29, 1993Dec 10, 1996Printron, Inc.Apparatus and process for screen printing
US8304678Jul 28, 2009Nov 6, 2012Hitachi, Ltd.Vacuum insulated switch-gear and its height adjusting method
US20100025376 *Jul 28, 2009Feb 4, 2010Hitachi, Ltd.Vacuum insulated switch-gear and its height adjusting method
EP2149894A1 *Jul 22, 2009Feb 3, 2010Hitachi Ltd.Vacuum insulated switch-gear and its height adjusting method
Classifications
U.S. Classification101/123, 101/126
International ClassificationB41F15/08
Cooperative ClassificationB41F15/0818
European ClassificationB41F15/08A4B