US2941499A

US2941499A - Production of lithographic printing plates

Info

Publication number: US2941499A
Application number: US678325A
Authority: US
Inventors: Ernest R Gutzmer
Original assignee: Intercompany Corp
Current assignee: Intercompany Corp
Priority date: 1957-08-15
Filing date: 1957-08-15
Publication date: 1960-06-21
Anticipated expiration: 1977-06-21

Description

June 21, 1960 E. R. GUTZMER paonucnou 0F LITHOGRAPHIC PRINTING PLATES 9 Sheets-Sheet 1 Filed Aug. 15 1957 Inventor Ernest R. (iutgmer J1 M .cBAM&/W );%MIM

fH-fornegs June 21, 1960 E. R. GUTZMER PRODUCTION OF LITHOGRAPHIC PRINTING PLATES Filed Aug. 15, 1957 9 Sheets-Sheet 3 Inventor Ernest R.G1 1t me'r June 21, 1960 E. R. GUTZMER 2,941,499

PRODUCTION OF LITHOGRAPHIC PRINTING PLATES Filed Aug. 15, 1957 9 Sheets-Sheet 4 Inventor Ernesf R. Gutgmer.

E5 flfiornegs June 21, 1960 E. R. GUTZMER 2,941,499

PRODUCTION OF LITHOGRAPHIC PRINTING PLATES Filed Aug. 15, 1957 9 Sheets-Sheet 5 r a Hui-0w w m n -a n 5 a new A Y v I (M-Vfl WNQ Tm nu. W M- K R M MNQ t 0a 0055 m r M E M. M

Mon-legs June 21, 1960 E. R. GUTZMER 2,941,499

PRODUCTION OFLITHOGRAPHIC PRINTING PLATES Filed Aug. 15, 1957 9 Sheets-Sheet 6 FORWARD 88v! ISE PB. 98-3 98-2 PG-l Inventor Ernest R. Gulgmer PRODUCTION OF LITHOGRAPHIC PRINTING PLATES Filed Aug. 15, 1957 June 21, 1960 E. R. GUTZMER 9 Sheets-Sheet 7 S m I nunbhoz nun: .roz L P J M 4. v m m a s u m m M am m u a v w a u o a m w w M a m A v 2 N 3 I M .I i

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8 9 j/mm, Baron/- June 21, 1960 E. R. GUTZMER 2,941,499

PRODUCTION OF LITHOGRAPHIC PRINTING PLATES Filed Aug. 15, 1957 9 Sheets-Sheet 8 Inventor Ern st R. Gutgmer :5 fl fi w M MM Mom egs PRODUCTION OF LITHOGRAPHIC PRINTING PLATES This invention relates to the production of lithographic printing plates and particularly to the coating of metal printing plates of this kind.

In the lithographic printing industry, many different kinds of metal printing plates are employed where the image to be printed is transferred to the lithographic plate by photographic processes, and with such metal .printing plates, it is necessary that a photographicallysensitized coating be applied to the surface of the printing plate. Depending upon the particular kind of printing plate that is being produced, the thickness and drying characteristics of the photo-sensitive coatingvaries considerably, but in every instance, the quality of the final lithographic printing depends in a large measure upon the quality and uniformity characteristics of the photo-sensitive coating that has been applied. The photo-sensitive coating is considered to be of poor quality where it includes bubbles or foreign matter, and if such coating varies unduly from the desired uniform thickness in the working areas of the plate.

In the past such photo-sensitive coatings have been applied, in most instances, on a whirler which usually constitutes a horizontal table mounted for rotative movement about the vertical axis, and after the plate to be coated has been disposed in a centered relationship on the whirler table, the coating material has been poured manually onto the center of plate while it is rotated with the table. It is customary just prior to the application of the coating material to flush the plate surface with water to insure cleanliness of the surface that is to be coated, and after the coating material has been applied and has leveled off to a smooth surface so as to fully dry the coating before the plate is removed from the whirler.

In prior whirlers, great difiiculty has been experienced in attaining even drying of the coated surface, and such whirlers have employed covers and drying air has been forced through the whirler along different paths. In an effort to attain more uniform drying, heating elements have in many instances been placed inside of the whirler, as for example on the inside surface of the cover, and this has been done in an effort to cause the center portions of the coated surface to dry at the same speed as the edges or corners of this surface. So far as I am aware, this expedient has not been successful except in those instances where an operator became particularly skilled in applying the heat for accurately determined periods.

In other instances, where the air has been heated before forcing the same into the whirler cabinet, but even where this expedient has been used, there has been a marked tendency for the edges or corners of the coating on a plate to dry ahead of the center portion. In all of the prior whirlers of which I am aware, there has been a marked tendency to circulate dust and dirt, including dry particles of coating, within the whirler cabinet so as to produce blemishes in the coated surface.

The prior coating procedures have required considerable time and manual labor in putting the plates in posi- 2 tiori, applying the flushing water and the coating, and thereafter removing the coated plate from the whirler, and because of uneven drying and because the several operations have been performed manually, there has been a considerable loss due to lack of quality and uniformity in the coated plates.

In view of the foregoing it is the primary object of the present invention to enable greater uniformity and high quality of coating to be attained in lithographic printing plates, and objects related to the foregoing are to enable uniform drying of the coating to be attained, and to enable the handling and coating of the lithographic printing plates to be accomplished automatically and in such a manner that uniformity of coating is attained while assuring that the coating is free from bubbles and foreign matter.

Another and related object of this invention is to provide an improved whirler in which the drying-air is supplied in such a way that uniformity of drying is attained throughout the plate surface while at the same time avoiding circulation of dust or dirt that might mar the coated surface.

Other and more specific objects of the present invention are to simplify the handling of lithographic printing plates to enable the same to be handled by lifting engagement with the top surface thereof, both before and after the coating operation, and to enable this to be done without danger of damage to the coated surface.

Another important object of the present invention is to enable a whirler to be started and stopped automatically, to perform its coating and drying functions, and to be thereafter unloaded automatically so that there is no need for the plates to be handled individually.

Another object is to provide a whirler wherein the plate is fully covered and shielded from outside dirt and dust during the entire flushing, coating and drying operation, and a related object is to accomplish this in such a way that the plate is stopped in a predetermined position or relationship after the drying operation, thus to adapt the whirler for cooperation with an automatic plate handling and transporting mechanism.

Another important object of this invention is to provide a novel and advantageous drive arrangement for the whirler table so that the plates may be positioned loosely thereon and yet will not be displaced on the whirler table during the starting and stopping of the whirler table.

Another important object of the present invention is to provide a plate handling and transporting unit that is adapted to handle lithographic printing plates by lifting the same and then transporting the plates individually to different locations, and a related object is to provide for vacuum lifting of the plates in such a way that the lifting action is attained by one set of lifting devices prior to the coating operation, and by another set of lifting devices after the coating operation, thus to assure said character that may be operated automatically" through a sequence of plate lifting, transporting and depositing operations so that the attention of an operator is not needed after a sequence of automatic handling and related operations has been initiated.

Other and further objects of the present invention will be apparent from the following description and claims and'are illustrated in the accompanying drawings which Patented June 21, 1960 changes may be made as desired by those skilled in the art without departing from the present invention.

In the drawings:

Fig. 1 is a plan view showing a plate handling and coating installation embodying the features of the invention.

Fig. 2 is a front elevational view of the installation.

Fig. 3 is a side perspective view of the whirler as viewed from the right in Fig. 1.

Fig. 4 is a front perspective view of the whirler with the cover open.

Fig. 4A is a schematic plan section showing the rela tionship of the air inlet and air outlets for the drying air.

Fig. 5 is an enlarged plan section of the whirler taken substantially along the line 55 of Fig. 2.

Fig-5A is an enlarged and somewhat schematic view of the control valve arrangement in the end of the coating-applying arm.

Fig. 6 is a front perspective view of the. whirlergenerally similar to Fig. 4 and showing a portion of the lifting and transporting unit in position over the whirler.

" Fig. Tie a perspective view of the lifting and trans-.

porting unit.

. Fig. 8 is a vertical sectional view through a portion of the lifting head of the unit shown in Fig. 7. l i Fig. 9 is a schematic view illustrating the power means and certain of the control switches that are associated with thetwo units. i

Fig. 10 is a schematic wiring diagram illustrating thecontrol circuit for the lifting and transporting units.i Fig. 11 is a schematic wiring diagram illustrating the control circuits of the whirler unit and indicating the manner of association thereof with the lifting and transporting unit. i

Fig. 12 is a schematic wiring diagram showing certain of the circuits of the whirler and thefrnaimer in which these circuits are controlled andinterrelated; and

Fig. 13 is a timing chart showing atypical automatic cycle.

THE APPARATUS IN GENERAL For. purposes of disclosure the invention is herein illustrated as embodied'in an automatic plate handling and coating installation 20 that comprises whirler 21 that has an automatic operating cycle in which lithographic plates P are flushed, coated and dried, and a plate handling and transporting unit 22 that is coordinated with the whirler 21 in its automatic operation so that the plate handling and transporting unit 22 is operable to pick up a lithographic plate P from a supply station I, transport the same to station IV at which the whirler 21 is located and deposit the plate P on the whirler, and after completion of an automatic sequence of flushing, coating and drying operation by the whirler 21, is operable to pick up the coated plate P and transport the same to station II of the plate handling unit 22 where the plate P is deposited on a stack of finished coatedplates.

The plate P that is coated by the present apparatus may be any type of lithographic plate, usually of metal, whether the plate has a grained surface or an ungrained surface, and the plate may be made of a single layer of metal such as an aluminum or zinc plate, or may comprise two or more layers of metal as is the case in bi-metal and tri-metal plates.

THE WHIRLER 21 The Cabinet The whirler 21 as shown in Figs. 1 to 6 of the drawlngs comprises a cabinet or housing 100 having a cylindricalverti'cal side wall 101 supported by a pair of front.

105 preferably has a plurality of upstanding returning pins 105P spaced outwardly from the location of the edges, of a plate that is in the normal centered plate location, and these pins areprovided as a saftey means so that in the event the plate P becomes displaced from its centered position, it will be held against excessive outward movement on the table.

The access opening 107 is slightly larger than the size of the largest plate that is to be coated with the whirler 21, and with this arrangement, it is possible to close the whirler during its operating cycle through the use of a tiltable cover or lid 108 that is of a minimum size and weight. The lid 108 is rectangular in form and is arranged so that it may rest on an upward flange 107F that is provided about the access opening 107. The lid 108 is mounted for pivotal movement about an axis parallel to its major axis by the provision of supporting arms 108A that extend upwardly and rearwardly from the rear cor The circulation of the drying air The cover 108 is arranged in the present instance to provide a portion of an air supply passage through which drying air may be forced into the housing 100, and for this purpose, an elongated air discharge opening 108D is provided in the cover 108 so as to extend from one of the rear corners of the cover 108 to substantially the central point of the cover. This air discharge opening 108D is thus located so that air discharged therefrom will move downwardly so as to strike an area of the plate P between the central point of the plate and one edge of the whirler table 105. The air that is thus forced intothe whirler cabinet through the discharge opening 108D strikes the whirling coated surface of the plate P at a considerable velocity and insofar as drying may be concerned, theeffective velocity, or its velocity relative to rotating coated surface, varies from the center of the plate to the outside edge thereof. The air at the outside edge may be said to be required to dry a greater area of the plate, and while this would theoretically indicate the need for a greater air volume at the outer edges of the plate, I have discovered that by making the discharge opening 108D of substantially constant width from end to end, the relatively larger volume of air per unit of plate surface near the center acts to cause drying to progress in the central areas at a rate substantially the same as in the outer areas where the higher efiective air velocity acts to dry the larger areas that are to be dried near the outer edges of the plate.

The drying air that is introduced into the cabinet through the openings 108D is, under the preesnt invention, circulated within the cabinet in such a manner that it does not pick up dust and dirt that may be present within the cabinet, and in accomplishing this purpose it may be pointed out that the bottom of the cabinet is closed except for a drain through which water and liquid coating material may pass. The air is discharged onto the upper surface ofthe plate and the table, and this is aocomplished by providing air outlets about the periphery of the housing 100 and just below the top wall 106. Thus the top wall 106 issupportedon aplurality of spaced supports 1068 that extend upwardly from the side wall 101, and between the supports 106$, air outlet passages 106D are provided. Thus the air that enters the housing through the opening 108D strikes the top of the table or the plate and may move outwardly over the plate and the table so as to escape from the housing through the opening 106D. Thus, in its entire path of movement through the housing 100, the air does not pass with any particular velocity to the bottom of the housing where it might tend to pick up dirt or particles of dry coating material and the like.

In practice I have discovered that the total area of the air escape openings 106D, and the location thereof in a circumferential direction relative to the inlet passage 108D has a bearing upon uniformity of drying. Considering that the table rotation imparts rotative motion in the same direction to the air, as indicated by the arrow in Fig. 4A, it may be pointed out that the best drying action is attained by blocking up a large proportion of openings 106D that are so chosen with respect to the inlet opening 108D, a large proportion of the drying air must travel almost 360 within the housing before it is discharged. In Fig. 4A, a typical arrangement of the discharge openings or outlet openings 106D has been diagrammatically illustrated, and those openings 106D that are blocked or closed are indicated by the letter B in Fig. 4A. In this arrangement some of the air may pass from the housing at several points along the rotative path, but the major portion discharges after it has traveled just slightly less than 360. The total area of the effective openings 106D is just slightly less than the area of the opening 108D. With this arrangement of the discharge opening 108D and outlet openings 106D, it has been found that circulation of dust has been for all practical purposes limited, and the coating material dries uniformly on the plate P so that there are no evidences whatsoever of ridges or double coating near the edges or corners of the plates. On the upper surface of the cover 108, a duct 110 is provided which is arranged to discharge through the discharge opening 108D and which extends rearwardly to the rear edge of the cover 108 where the rear end of the duct 110 engages the forward end of a main air supply duct 111. This engagement or connection of the ducts 110 and 111 is of course broken When the cover 108 is raised to its open position, as will be evident particularly in Figs. 3 and 4 of the drawings, and yet when the cover 108 is returned to its closed position, the connection of the two ducts is re-established so that drying air may be forced through the ducts and into the housing 100 as will be described in some detail hereinafter. 1

Operation of the whirler cover The cover 108 is urged to its closed position by gravity, and is arranged to be opened by means of a cable 112 that extends from a connection at the midpoint of the cover 108 upwardly and rearwardly and over a pulley 112P that is carried at the upper end of a supporting column 112C. This cable 112 extends downwardly along the column and then under the whirler 21 where the cable is connected to apiston of an air cylinder AC-l08 that is governed and controlled as will be hereinafter described to raise and lower the cover 108 automatically in the operation of the whirler. Air is supplied to the cylinder AC-108 under control of a solenoid valve SV-108 of the combined cu-t-ofi and vent type. This valve is open when it is not energized, so that the cover 108 is held open, and when the cover is closed during the coating and drying periods, the valve is energized so as to vent the cylinder AC-108 and allow the cover 108 to close.

The swingable coating and flushing arms Means are provided for applying flushing water and coating material to the plate P in the operation of the whirler 21, and in order to facilitate alternate use of the machine for applying coating of two different kinds,

such means are duplicated in the whirler, and specific description will be confined to one of such means. Thus, a pair of coating arms 115 and 115-1 are provided as shown particularly in Figs. 1, 4A and 5, and the specific structure of the arm 115 will be given hereinafter. Thus the arm 115 extends from and is fixed to a vertical shaft 116 that is disposed Within the housing and closely adjacent to the vertical wall 101 thereofso that by rotative movement of the shaft 116, the arm may be moved between a retracted position adjacent the side wall 101, shown in full lines in Fig. 5, and an operating position wherein the end of the arm 115 is disposed over the center of the table, as shown in dotted lines in Fig, 5. The arm 115 is operated back and forth between these positions by means including an air cylinder AC115 that has the piston rod 117 thereof connected to an amt 116A that is rigidly fixed to the lower end of the shaft 116. Spring means 115S normally urge the arm 115 to its outer or retracted position. The operating cylinder AC-115 is actuated to project the arm 115 under control of a solenoid valve SV-115 in an air supply line, and this is done automatically as will be described.

The arm 115 has three

pipes

115W, 115A and 115C mounted thereon so as to extend from the inside or remote end of the arm beyond the shaft 116 and through an access opening provided in the side wall 101 of the housing by eliminating one of the supports 1068 to provide one long opening in the location that would otherwise constitute two openings 1068. The pipe 115C is arranged to supply coating material and has a flexible supply hose 118C connected thereto which includes a filter 118F, while the line 115A constitutes an air line whereby controlling air may be applied to a control valve 120 that is carried on the inner end of the am 115, and a flexible supply hose 118A is connected to the extended end of the pipe 115A. The pipe 115W serves as a water supply line, and at its outer end, just outside of the housing 100 is connected to a flexible water supply line 118W.

The valve 120 that is located at the inside end of the arm 115 is arranged to control the flow of coating material through the valve 120, and as shown herein, the valve 120 is of elongated cylindrical form with a casing 121 Within which a piston-like control valve member 122 may be re'ciproacted. The valve member 122 is urged to a normal position by a spring 123, and is arranged to be actuated in a right-hand direction as viewed in Fig. 5A to its alternate or other position by means including an air cylinder 124, the piston of which acts upon the valve member 122. The air line 115A is connected to one end of the air cylinder 124 so that when pressure air is supplied through the line 115A, under control of a solenoid valve SV-1'18A, the valve member 122 will be shifted against the action of the spring 123 to its second position.

The valve casing 121 has an outlet spout or nozzle 125 upon the lower end of which a cap 125C is threaded so as to hold a strainer or screen 1258 removably in position across the outlet spout 125. This screen is of extremely fine mesh, on the order of 70 to 200 mesh per inch, so that the screen acts not only to break up and prevent passage of air bubbles that may be present in the coating material, but also to remove dust, dirt and the like that may be present in either the coating material or the water that is to pass into the valve 120.

The water supply line 115W is connected to the casing 121 in such a position that water may flow through the casing and the outlet spout or nozzle 125 when the valve member 122 is in the normal position in which it is shown in Fig. 5A. The coating supply pipe 115C is connected .to the casing 121 so that when the valve member 122 is in its other or actuated position, the coating material may flow from the pipe 1150 through the outlet 125 and, of course, at the same time the flow of water is cut off. It might be noted that the flow of coating material is governed only by the valve member 122, but that the water flow is additionally governed by a solenoid.

valve SV-115W that is includeddin the flexible water The whirler table drive The whirler table 105 is mounted and supported on a rotatable vertical shaft 126 and is driven from a motor 127 by means including a friction-type variable speed mechanism 128 that has its output shaft connected to the shaft 126. The variable speed mechanism 128 is of the friction-type that is adjustable by means of an adjusting lever 128L so that it may vary from a zero output speed to a suitable maximum speed. In the operation of the present whirler, the speed of the whirler table 105 is varied gradually in starting and stopping so that there is a uniform acceleration and deceleration, and this is done so.

that the plate P may rest in a predetermined position on the table 105 without clamps or securing devices, thus to enable the plate P to be readily and easily put in place or removed from the whirler table 105 by automatic means. The speed varying lever 1281 is operated between its zero position and its maximum position by means including an air cylinder AC-105 that is constantly urged to a zero speed position by air supplied at a reduced pressure through a line 105C to one end of the cylinder. The lever 128L is controlled as to speed of operation in both directions by means of a hydraulic check cylinder HC-105 that is connected through a common linkage 129 to the air cylinder AC-105 and the lever 12814. Air is supplied to the forward end of the air cylinder AC-105 through an air line 137B under control of a solenoid valve SV-105 of the combined cutofi and vent type.

Whenthe whirler table 105 is stopped it is desirable that the plate P that is carried thereby be located in the same rotative position, thus to facilitate automatic handling of the plate and enable the finished plates P to be stacked in a substantially uniform stack by the automatic entering means 22. In the present instance, since the plates P are rectangular in character, provision is made for stopping the whirler table 105 in either one of two rotative relationships that are displaced 180 from each other. In accomplishing this positioning, the shaft has a locating plate 130 fixed thereon beneath the whirler table 105, and this plate has a pair of locating notches 130N at diametrically opposite points as indicated in Fig. 9. These notches 120N are adapted for cooperation with a locating plunger 131 that has a pointed end that is adapted either to ride on the circular outer edge of the plate 130 between the notches or to enter one or the other notches 130N. The locating plunger 131 is actuated by an air cylinder AC-131, the plunger 131 being formed as a part of the piston of this air cylinder. The plunger 131 is urged to a retracted position by a spring 1318, and when the plunger is to be rendered effective, air is supplied to the rear end of the cylinder AC-131 from a line 137A by operation of a solenoid valve SV-131. Thus, in the stopping or deceleration of the table 105 that is accomplished by the variable speed mechanism 128, the air cylinder ACE-131 is operated to urge the plunger 131 toward the disc 130 when the rotative speed of the table 105 has been reduced substantially to zero. The solenoid valve SV-131 is operated at the proper time under control of a switch 8-128 that is engaged and operated by the speed control lever 128L as this lever reaches its zero speed setting. The plunger 131 then moves radially into engagement with the edge surface of the disc 130, and when one of the notches 130W moves into alignment with the plunger 131, the plunger is actuated into the notch so as to stop the table 105 and locate the same in one of the two positions determined by the notch 130W. The table is thus stopped with a predetermineddiameter thereof parallel to the major axis of the opening 1 07, and the plate P may beremoved easily by ver tical lifting thereof. As the plunger. 131 moves into one of the notches, an abutment on the plunger engages-and actuates a switch 5-131 which serves as a controlling means for initiating further automatic. operation of the system as will be described.

The coating supply means Thev coating solution may be either a photo-sensitive: solution or a simple gum solution for protecting the surface of the plate, and the two arms 115 and 115-1 maybe, allocated to two different coating materials that are to. be used selectively. For purposes of disclosure it may be considered that a photo-sensitive coating mate-. rial isrfed froma, supply container 135 that is preferably supported in an elevated position and which is connect-' ed to the flexible coating supply line 118C of the arm. 115,. The coating is fed under-pressure from the supp ply container 135 and this is accomplished by closing the top of the container and supplying air thereto from a pressure air source 136 through the lines-137 and 138" and a pressure regulator 139. By adjustment of the pressure regulator, the feeding pressure may be adjusted as desired and this feeding pressure coupled with control of the feeding time within fairly accurate limits serves to determine the quantity of coating material that is fedronto each of the plates P that is to be coated' Supply of drying air The drying air that is supplied to the housing through the ducts and 111 is furnished, by a blower 140, and the air supply passes through a rather elaborate duct work 14 1 which as diagrammatically indicated in, Fig. 9 of the drawings, includes a filter 142,'a heater, 143 and a humidifier 144 so that eliicient and uniform drying operations will be attained, and lllllIOClllOilOIlaOf the dust or the likev onto the coating surface of the plate. P will be avoided.

The operation of the whirler 21 is controlled automatically by a whirler timer, the operation of which is initiated under control of the lifting and supporting unit 22 as will be described, and when the cycle of operations. of the whirler has been completed, the completion of the opening movement of the cover 10.8 causes one ofthe arms 10811 to engage and close a controlswi-tch' 8-108 that is mounted on the related one of the leg ex-v tensions E, and this closure of the switch 8-108 is effective to again initiate operation of the lifting and sup.- porting unit 22 so that the coated plate P is lifted from. the whirler table 105 and is transported to station II where it is lowered and deposited upon a pile of finished coated plates.

THE LIFTING AND TRANSPORTING UNIT 22 In general The lifting and supporting unit 22 comprises a square cabinet-like base 400 from the center of which a rotatively mounted column 401 projects upwardly, and a rigid frame 402 projects outwardly from the column 401 to support an outer mounting member 403 in a vertical position wherein it is parallel to the column 401. In the present instance, the frame 402 is formed by a pair of

parallelarms

402U and 402L. Onthe outer face of; the frame member 403 an air cylinder 405 is mountedin a vertical position with its piston rod 405R extending downwardly therefrom and carrying a horizontally positioned lifting head 408 at its lower end. The lifting" head 408,comprises a horizontal wall WSW witha downwardly projecting outer flange 408F, and beneath the wal1 408W two sets of

suction cups

410W and 410D are mounted so that these sets of suction cups may be used selectively to engage and lift plates P will be' described: Y F

The suction cups and selection thereof The set of suction cups 410W is mounted in a fixed position, and all of the cups 410W of the set are con-' nected together by pipes 411 to which a vacuum source is connected as will be described. The cups are relatively large, and are disposed in a rectangular pattern about 12 to 16 inches apart so that in lifting a plate P, the lifting forces applied by each cup are relatively small.

The suction cups 410D are mounted on the lower ends of the piston rods 412 that extend into the piston and cylinder devices 412C that are mounted above the wall 408W, and a spring 4128 in each cylinder serves to urge the related cup 410D to an upper or retracted position shown in Fig. 8. The several suction cups 410D may be connected to a vacuum source by a pipe 413 and this connection is controlled as will be described. When it is desired to lower the suction cups 410D to an effective position shown in dotted outline in Fig; 8, air is supplied to an upper cylinder 412C through an air line 413A.

As above pointed out, the sets of

vacuum cups

410D and 410W are adapted for selective use, and the cups 410D are raised and lowered under control of an air valve 415 while the sets of cups are therefore selectively associated with a vacuum source through a control valve 416. This control valve 416 has a medially located air inlet 413A extended from the pressure air source, and a slidable valve member 415M is slidable between two positions to connect the inlet selectively with a vent 415V or with the air cylinder 412C. Solenoids 415W and 415D at opposite ends of the casing may be energized selectively to shift the valve member 415M to one or the other of such positions.

The vacuum valve 416 has a medial inlet pipe 420 extended to the vacuum pump, and a valve member 416V is slidable between two positions to connect the line 420 selectively with the wet cups through line 411 or the dry cups through the line 413.

Solenoids

416D and 416W at opposite ends of the valve may be selectively energized to shift the valve member 416M between such positions. The

valves

415 and 416 and the several piston and cylinder devices 412C are connected by a cover member 408C. During operation of the unit 22 the vacuum line 420 is continuously connected to the vacuum source 419. When a plate P is to be dropped or released from the suction cups, this is accomplished by feeding pressure air from a line 421 into the vacuum line 120, The air for this purpose is controlled by a normally closed solenoid valve SV-421 of the simple cutoff type that is located in the air line 421. In the vacuum line 420, between the valves 416 and SV-421 a vacuum sensing switch S-420 is located and this switch functions in the automatic control of the unit 22 as will be described.

Actuation of the lifting head 408 The lifting head 408, being supported on the piston rod 405R may in some instances tend to rotate about the axis of the cylinder 405, and in the present instance, this is prevented by a pair of guide rods 422 that extend upwardly from the head 408 on opposite sides of the two

arms

402U and 402L. These rods 422 are relatively light and have bracing members 422B connected thereto. The guide rods 422 serve to keep the longitudinal axis of the lifting head 408 in the plane of the frame 402.

The head 408 tends normally to move downwardly under the action of gravity, and when the head is to be moved upwardly, air is supplied to the lower end of the cylinder 405 through an air line 425'.

When the head 408 reaches its upper position, a block 422B on one of the rods 421 contacts a control switch 8-405 mounted on the arm 402U so as to close the switch, and this switch is utilized in the automatic control of the machine as will be described.

The air line 425 is connected through a stub line 425$ to the pressure air source 136, and a solenoid valve SV-425 of the combined-shut-oflr and vent type is included in the stub line 4258. Between the cylinder 405 and the vacuum SV-425, the line 425 has a pressure sensing switch 8-425 that is arranged to be normally open, and this switch is closed when the pressure in the cylinder 405 is reduced substantially to zero. This condition occurs when the lowering of the head 408 has been completed so that the effective suction cup rests upon a stack of plates P. The closure of the pressure sensing switch 8-425 is utilized for automatic operation of the machine to cause release of a plate P in a dropping operation, the initiation of the upward or lifting movement of the head 408, or to cause lifting of the head 408 after a plate P has been effectually engaged by the vacuum cups in a lifting operation as will be described.

Rotative actuation of the column 401 The column 401 as hereinabove described, is arranged for rotative movement, but in the present instance, such rotation is limited to some extent by a supporting or stiffening frame 430 that extends upwardly from the base 400 and then outwardly at 430A to provide a bearing for the upper end of the column 40. The location of the frame 430 is best shown in Fig. 1 of the drawings and this location is such that lifting head 408 may be moved from the loading station I in a clockwise direction to stations 11, III and finally into station IV where the frame 402 is located on the opposite side of the supporting or stiffening frame 430. It will be observed that in moving into station IV, where the whirler 21 is located, the lifting head moves in a clockwise direction, and this is taken into account in the positioning of the whirler 21 so that the lifting head 408 moves toward the open cover 108 and over the access opening 107, as will be evident in Fig. 6 of the drawings.

The rotative movements are applied to the column 401 by a reversible electric motor 432 which operates through a reduction-gear unit 433 to drive the vertically extended output shaft 434. On this output shaft a small sprocket 435 is mounted and is connected by means of a chain 436 to a relatively large sprocket 437 that is loosely mounted on the column 401 within the base 400. The sprocket 437 constitutes the driving element of a friction clutch, the other or driven element being in the form of a friction disc 438 that is splined on the column 401 and which is pressed downwardly by a spring 439 into frictional contact with the sprocket 437'. This provides a factor of safety in the operation of the machine so that in the event of a collision of the lifting head 408 with other apparatus, the frictional drive will slip.

As the column 401- is rotated, means are effective to sense the rotative position of the column so as to indicate the position of the lifting head 408. Thus the column 401 has .a radial switch operating arm 440 fixed thereon within the base 400, this arm being located in the plane of the supporting frame 402, and the arm 440 is arranged to actuate switches 8-1, 8-11, S-III and S-IV as the lifting head 408 is moved into the correspondingly identified positions or stations. These position-indicating switches are utilized as will hereinafter be described to control certain aspects of the automatic operation of the machine.

When the column 401 has been rotated to any selected position, it is accurately located and locked in this position by means of a locking plunger 445 that is operated by an air cylinder 445C so that the locking plunger may engage with any one of four equally spaced locking notches 445N that are formed in a locking disc 445D that is fixed on the column within the base 400.

a The plunger 445 is urged toward a released position by a spring 4458, and when the plunger 445 is to be locked, air is supplied to the outer end of the cylinder 445through an air line 446 that is extended from the supply line 137'. A solenoid-valve 'SV-445 is included in the line 446 and this valve is or the combined cutofi and vent type. Between the valve SV-445 and the cylinder' 4456, a pressure sensing switch 8-445 is connected with the line 446 so that the sensed presence or absence of pressure in the cylinder 4450 may function in the automatic control of the unit 22 as will be described.

OPERATION AND CONTROL In the operation and control of the present installation, several timers are employed. The first of these timers may be termed a cycle timer that is of the motor operated type driven by a motor 500M and having a plurality of cam operated switches CS-l to 03-33 inclusive. These switches are of the double throw type, and in the present instance, the connections are made in most cases between the common terminal and the normally closed contacts of the respective switches, the switches being heldopen by the related-cams, and being allowed to close at appropriate times in the cycle of operation of the timer 500.

The second timer is a coating solution timer 501 that is driven by a motor 501M and is utilized to govern the length ofthe period during which the coating material is fed from the arm 115 onto the plate that is being coated. A similar timer 501G is also provided and is system and with the position-indicating switches 8-1 to S-IVin initiating rotative movement of the lifting and transporting device as required to any selected one of the several stations thereof, and in determining the proper direction of rotation of the column 401. This selection andv control involves the use of a 2-way motor starting relay 510- that has one coil 510L which when energized, closes circuit to the motor 432 in such amanner as to cause left-hand or counterclockwise rotation of thecolumn 401,- while an operating coil 510R may be energized to cause rotation of the column 401 in a righthand or clockwise direction. The power source comprises lines L1, L2 and L3,- and the output to the motor 432 is extended from the starting relay through the wires T1, T2 and T3 in a conventional manner. The relay also includes sets of interlocking contacts 511L and 511R that are efiective, as will be described, to prevent simultaneous operation of the two operating coils of the starter.

Selection of directionof column-rotation The direction selecting means comprises a plurality of relays that are energized in accordance with the station to which the head 408 is to be moved, and this energization is controlled in part by the position-indicating switches S 1 to S IV, and in part by either the automatic selecting action of the timer 500 or by manually operable means.

Due to the nature of the lifting and transporting unit 22, it: will be clear that when the head 408 is to be moved into station I from any other station, this will always require left-hand rotation, and in the same way, when the headis to be moved into station IY from-any other station,-this must always be accomplished by right-hand rotation-otthe column 401. As to selection of stations II and III, however, as the destination for the head 408, it is possible, depending upon the previous location of the head, that the movement required may be either in the righthand or a left-handdirection. The relay system is effective to automatically determine the required direction offrotation under suchcircumstances.

, Thusa relayiL-L is provided for use'in the selection of station I, and'a single relay IV-R is provided for use in selection of station IV as a destination. In contrast to this, two relays II-R and II-L are provided for use in selecting station II, and two relays III- -R and III-L are provided for use in selecting station III as a destination. Finally, a relay II-RL and a relay III-RL are provided for use in connection with the selection of stations II and III respectively.

The relay I-L has a set of normally open holding con-' tacts I-L-l and a set of normally open control contacts I-L-Z. The relays II-R, II-L, III-L and IV-R also have similar sets of holding and control contacts that are similarly identified with a prefix identifying the respective relays and a suflix identifying the corresponding contacts.

In the relay II-RL, three sets of normally open contacts II-L-l, IIRL-2 and IIRL-3 are provided, and three similar sets of normally open contacts are provided in the relay III-RL.

In providing the energizing circuits for the above as: scribed relays and the operating coils of the starter 510,- circuit is extended from line Wire L-2 by a wire 601 having branches extended to one terminal of the operating coils of all of such relays and the starter 510.

The other terminal of the starter coil 510R is connected through the interlock contacts 511L to a wire 650R and when the relay coil 510R is to be energized, circuit is ex tended from line wire L-1 to the wire 650R through the No. 2 or control contacts of one of the relays II-R, III-R or IV-R, as will be described in some detail hereinafter. Similarly, the other terminal of the operating coil 510L is connected through the interlock contacts 511R to a wire 650L and when the coil 510L is to be energized, circuit is extended from line wire L-1 to the wire 650L to the No. 2 or control contacts of one of the relays I-L, II-L and III-L.

The relays II-RL and III-RL are utilized in determining whether the right-hand or left-hand relay relating to station 11 or station III is to be actuated, and this determination is made by circuits that are extended through the relay conacts of these relays from the position-indicating switches 8-1 to S-4.

The operation in respect to relays LL and IV-R will however be first described. Initially, such operation will be considered as being initiated by manual selection rather than by automatic selection, there being four push button switches PB-l to PB-4 allocated respectively to stations I to IV. In considering any particular stationselection problem, the present position of the head 408' must be taken into account, and as a first example it willbe assumed that the head is at rest in station II, and that it is desired to have the head move in a left-hand" or counterclockwise direction to station I. When this is to be done, the push button switch PB-1 is actuated and this results in the energization of relay I-L. Keeping in mind that one terminal of the operating coil of this relay is connected to the line L-2, the closure of switch PB-1 extends circuit from a wire 615 that is connected to line wire L-l to a wire 610 that is extended to the other terminal of tbe'operating coil of this relay. The operation of the relay of course closes the control contacts I-L-2 so that circuit is extended from a wire 652 that leads from line wire L-1, through a branch lead 6524 and the control contacts to the wire 650L.

The coil 510L of the starter is thus energized to cause rotation of the column 401 in a left-hand direction, and such movement continues so long as the holding contacts I-L-1 are kept closed. Thus, one of the holding contacts is connected by a branch lead to the wire 610, and the other of thesecontrol contacts is connected by a wire 603 tothe normally open contact of the position indicating switch-S1.- This switch is of the double-throw type with its columncontact connected to the wire 15.

When the relay 1L is energized as above described;

the starter coil 510L will be energized so as to extend circuit to the motor 432 to rotate the column 401 in a lefthand or counterclockwise direction, and as an incident to connect to the motor circuit, the solenoid valve SV-445 is energized to release the V-lock. The energizing circuit for the valve SV-445 is provided by extending the Wire T-3 to one terminal of the valve solenoid and by connecting the other terminal of the solenoid to the line wire L-2 by a wire 653. The rotation of the column 401 continues until the head 408 reaches station I, and at that time the switch 8-1 is actuated by the arm 440 to break the running circuit that has been extended by the wire 603 through the holding contacts of the relay 1-1. The relay I-L then drops out so that the motor 432 isdeenergized, and this de-energizes the solenoid valve SV- 445 so that the V-lock returns to its effective position and accurately locates the head 408 in station I.

The selection of station IV is accompanied in generally similar manner by actuating the push-button switch PB-4 which extends circuit to the other terminal of the relay IV-R in the following manner:

I In establishing this circuit, the switch S-4 is utilized, and since the head 408 is in position I in the assumed example, circuit is extended from the wire 615 through the normally closed contact of the switch S-4 and a wire 609 to one contact of the switch PB-4. From the other contact of this switch a wire 614 is extended to the normally open contact of the switch S-108 which serves as a safety switch which is closed only when the whirler lid 108 is fully open. If the whirler lid is in effect open so that the switch 8-108 is closed, circuit is extended by wire 614B to the other end or terminal of the coil of the relay IV-R, thus to energize this relay. When the relay is energized, circuit is extended from line I through the control contacts IV-R-2 of this relay to the wire 650R, thus to cause operation of the motor 432 to drive the column 401 in a right-hand or clockwise direction. The relay IV-R is held in its actuated condition by a holding circuit that extends from the Wire 6143 through the holding contacts IV-1 and a wire 609 to the normally closedcontact of the switch S-4. Hence, when the head 408 has moved into station IV, the arm 440 actuates the switch S-4 so as to break the holding circuits which causes the head 408 to be stopped and located in station IV.

As to the selection of stations II and III, the selection circuits are somewhat diiferent and will be described particularly with respect to the selection of station II. Thus, assuming that the head 408 is in station IV, the selection of station His accomplished by actuation of the push-button switch PB-2. When this is done, circuit is extended from the wire 615 to a Wire 6111 which is extended to the other terminal of the operation coil of the relay II-RL so that this relay is energized, and it is through the contacts of the relay I-I-RL and the cooperating contacts of the switch 8-1 to 8-4 that a further selection is automatically made which determines whether the relay lI-R or II-L is to be energized. Thus the energizing circuit for the relay II-R is extended by a wire 655 toone of the contacts II-RL-l, and from the other of these contacts a wire 602 is extended to the normally open contact of the switch S-l. Similarly, a wire 656 extends from the other terminal of the operating coil of the relay II-RL to one of the contacts II-RL-2 and also to one of the contacts II-RL-3. The other contact II- RL-2 is connected by a wire 606 to the normally open contact of the switch S-3, while the other of the contacts II-RL-3 is connected by a wire 608 to the normally open contact of the switch S-l.

Similarly, connections are provided to the relay contacts of the relay III-RL. Thus the relay II-RL has the other end of its operating coil connected by a wire 612 to one of the contacts of the push-button switch PB-3. The other terminal of the operating coil of the relay II-R 14 is connected by a wire 657 to one of the contacts HI- RL-1 and also to one of the contacts II-RL-3. 'Ihe other contact II-RL-3 is connected by a wire 602B to the wire 602, while the other contact III-RL-Z is connected by a wire 604 to the normally open contact of the switch S-2. The other terminal of the energizing coil of the relay III-L is connected by a wire III-7 to one of the contacts III-RL-3, the other of these contacts being connected by a wire 608B to the wire 608. The connections that have thus been described constitute the selecting contacts that are necessary to determine the right-hand and left-hand characteristics of the movement to be imparted to the column 401, and additional circuits are provided from the relay II-R, II-L, III-R and III-L for energizing the operating coils of the starter 510 selectively, and further circuits are provided for holding the operated relays until the selected station has been reached.

Thus the control contacts of the relays II-R and III-R are connected by the line 652 and the wire 650R so that when one or the other of these two relays is energized, the operating coil 510R of the starter will be energized. Similarly, the control contacts of the release II-L and III-L are connected by the wire 652 and the wire 650L to energize the starter coil 510R when these two relays are energized. The running circuit for these two relays is provided as follows:

The relay II-R has one of its contacts II-R-l connected to the wire 655, while the contacts II-L-l are connected to the wire 656, and the other contacts of these two pairs are connected by a wire 658 and from the wire 658 a wire 605 is extended to the normally closed contact of the switch S-2. One of the contacts III-R-l is connected to the wire 657 while one of the contacts III-L-l is connected to the wire 657A, the other two contacts of these sets are connected together by a wire 659. A wire 607 extends from the wire 659 to a normally closed contact of the switch 8-3. It might be pointed out that the common contacts of all of the switches S-1 to 8-3 are connected to line wire L-l by wires 615.

With the relays connected as above described, actuation of the switch PB-3 While the head 408 is located in station III, causes the desired left-hand movement of the head 408 in the following manner:

The circuit is extended through the switch PB-3 from the wire 615 to the wire 612 which of course causes operation of the relay III-RL, and such operation of this relay serves to select and cause energization of the relay III-L. Thus it will be observed that of the three sets of contacts of the relay III-L, the contacts III-RL-3 are the only ones' that are connected back to line 615. Thus, this set of contacts is connected by wires 608B and 608 to the normally open contact of the switch 8-4, but since head 408 is at this time in station IV, a switch 8-4 will be operated so that circuit will be extended to the lines 615. As to the other two sets of contacts in the relay III-RL, the contacts III-RL-l are connected through the wire 602 to the normally open contact of the switch S-1 which of course will be open at this time, while the contacts III-RL-2 are connected through the wire 605 to the normally open contact of the switch S-2 which is also in its open relation. Hence it will be clear that of the three possible circuits through the contacts of the relays III-RL, the position-indicating switches of the unit 22 determine that circuit-s shall be extended only to the relay III-L. When the relay III-L is energized circuit is extended to the starter coil 510L so that left-hand rotation of the column 401 will move the head forward from station IV to station III where the relay III-L will be caused to drop out due to the opening of the normally closed contact of the switch 8-3.

A similar selection and operation takes place when the push-button PB-2 is pushed so that the column 401 will be rotated in the proper direction to move the head from the position which it is then located to station II.

Vertical riiovements of the head 408' Additional control switches are provided, and one of these is an oiT-on control switch 8-660 that may be used to connect the line L- 2 to the terminal board 661 of the relay panel where a series of connected terminals 661T are energized from the line L-Z when the switch 8-660 is closed. 7 p

g In addition, a push-button switch PB-6 is providedfor manually initiating thepickup operation of the head 408, and a push-button switch PB-5 is provided for initiating operation of the drop cycle of the head.

In carrying out the pickup and drop cycles several relays, are included in the relay box. Thus a relay D-5 and D-6 are provided for functioning in the drop cycle of the machine, while a pickup control relay P-7 is provided for functioning in the pickup cycle; In addition, relays are provided for governing the shifting of the cups 416D and for governing the supply of vacuum to the two-sets of cups. Thus a relay DC-8 functionsjwhen the; dry cups 41033 are to operate, while a relay WG-9 functions when. the cups 410W are to operate, and the operation of the relays DC-8 and WG-9 is interrelated with the rotative position of the head 408 as to insure the use of the proper cups according to the methodof. use to: which the lifting and supporting device is to-beput. All of these' relays embody control contacts as will be described.

Pick-up operation of head 408 Thus, when a pick-up operation of the head 408' is to be initiated the manual pickup sWiteh PB-6 may be actuated and this closes an energizing circuit for the relay P-7. This energizing circuit is extended' from a' terminal A by a wire 663 to one end of the coils of the relay P-7 and a wire 664 extends from the other end" of this coil to a terminal T-20. Closure of the switch PB-6 has extended circuit to a terminal 21 so that circuit is further extended by a wire 665 to the normally closed contact of the vacuum sensing switch S420,'the common contact of which is connected by a wire 666 to' a terminal T-1 which is connected to line wire 1 -2. This serves to energize the pickup relay P-7, and when this is done a holding circuit is closed through a normally open contact P-7-1 of this relay to the terminal T41. Thus ther'elay P-'7 will be held in its energized position until the establishment of a vacuum at the eifective cups has closed'the switch 8-420 to be operated, and when this takes place the holding circuit will be broken and the relay P-7 will be energized.

I The relay P-7 also provides a control'circuit whichlis effective to release the air pressure in the lifting cylinder 405. Thus this control circuit is provided by normally open contacts P71, one of which is connected to the wire 663 and the other of which is connected toa wire 668 that extends to a terminal T-22. From the terminal T-22' a wire 69 extends to one terminal of the solenoid valve SV425, the other terminallof which is connected by a wire 670 to the normally open contact valve, the pressure sensing switch 8-445 which is associated with the air lock device. The common terminal of the switch 8-445 is connected by a wire 671 to the wire 666; thus to extend circuit to the line wire' L2. circuit will thus be closed only when the locking piston is effective, and because the lifting piston 405; is being vented, the head 403 will move gradually downwardly at a speed depending upon the size of the vent that has been opened. The downward movement of the head. 408 will continue until the head comes to rest, and this normally occurs when effective suction cups come into contact with a plate P that is to be lifted. The vacuum pump is the r; efiective to build-up a vacuum at the. effective. cups, and when this vacuum has reached a predetermined amount, the switch 5-420 is operated so as to break the holding circuit of the relay Pe7. The valve SV 425 is therefore de-energized and again supplied to the lifting cylinass-sass iii dei- 405 $5 that the head 40s win return to its upper ast 5 tion, and the desired rotative movement of the cplumn 401 may then be initiated as described hereinbefore.

Dropping cycle of the head 408 When the head 408 is to be moved through a dropping cycle, this may be initiated by actuation of the drop switch PB5' which is connected across terminals T-18 and T-19 of the panel. This establishes anenergizing circuit for the drop relays D-5 and D-6. Thus wires 673; and 673A are extended from the terminal T-ISA to-one end of each of the coils of the relays D-5 and D -6.l The other ends of these coils are connected by a wire 674 to the terminal T-17. Closure of the switch PB-S has; of course, connected these two terminals and circuit extended from the terminal T-18 through a wire 675 to the normally open contact of the vacuum sensing which at this time would be closed due to the pressure of a plate across the vacuum cups. Circuit would thusbe extended by the wire 666 to the line wire L52 sothat both of the relays D-5 and D- -6 would be energized. When the relays D-5 and D-6 are energized a holding circuit is provided by relay contacts D-S-L, one of these contacts being connected to the wire 674 and the other of these contacts being connected by a wire 677 to the terminal T 18. This holding circuit will thus" maintain the relays D-5 and D-6 energized until such time as the vacuum at the cups has been released so as to cause thesensing switch S 420 to return to its normal condition which serves to break the holding circuit of the relays D5 and D-6. A

The relay D-5, when energized, serves to govern the lift cylinder 4% through relay contacts D5'2',' one of p which is connected to the wire 673 and the other of which is connected by a wire 668A to the wire 668. This cir cuit extends through the solenoid valve SV-425 and the sensing switch S445 so that it the column 401 is locked. the air from the cylinder 405 will be vented so as to lower the head 408.

is connected by a wire 677 to the terminalT-2.3.' A wire 6'78 extends from the terminal T 23 to the normally" closed contact of the air pressure sensing switch 8-425; the common contact of which is connected by a wire 679 to the wire 666 so as to extend the circuit bacli to extended through a wire 598 that is .conriectedftoj the.

line L-Z. v

The circuit that has just been described is not closed immediately but is merely conditioned through thepressure sensing switch S4Z5, and when the 'air' pressure in the lift cylinder 4&5 reaches zero, the switch is" closed so that the air cylinder 421 is actuated, thereby to feed pressure air into the vacuum line for releasing the'vacuum' and dropping the plate P from the vacuum cups This circuit is maintained for a predetermined time through operation of a timer 505 that has a relatively short time. period on the order of six seconds during;

which the energizing circuit to. the air control solenoid SV-42l is maintained even though the relay D6 becomes de-energized. Thus the timer 505 has wires 506. and 597 extended therefrom to the terminal T- IS and. the terminal T-l respectively, thus to be connected to the two line wires, and the wire 506 is connected; di-. rectly to the timer motor. This establishes a wnnecaen; to line wire L-l, and the timer 505 is startedbyl a circuit t rminal T49. The terminal T-19, of course, is initially 17 connected to the line wire L-2, and after the motor is started a switch 505$ thereof is closed for the predetermined timer period to connect the wire 507 to the other side of the motor circuit. Thus, the insertion of the pressure air to the vacuum system is continued for the time period to insure dropping of the plate P.

Selection of suction cups 410W r 410D It has been pointed out hereinbefore that the dry.

suction cups 410D and the wet suction cups 410W are used selectively to insure that proper selection of cups is attained, and to insure proper connection of the vacuum line to the selected cups, and to do this the

valves

415 and 416 must be actuated. This is done under control of the relays DC-ti and WC-9 in cooperation with the rotative position of the column 481 as such rotative position is indicated by the switches 8-1 to 8-4.

In accomplishing this the relays DC-S and WC-9 are both operated each time the pick-up relay P-7 is operated. Thus the wire 664 has a branch 664A that is connected to one end of each of the coils of the relays DC-8 and WG-9, while the other terminals of these relay coils are connected by a wire 680 to the terminal T-15A. The common relay contact of the relay DC-8 is connected by a wire 681 to terminal T-25, while the common contact of the relay WG-9 is connected by a wire 682 to the terminal T-24. The normally open contact of the relay DC-S is connected by a wire 683 to the wire 608 which extends to the normally open contact of the switch S-4 so that this side of the control circuit of the relay WG-9 can be completed only when the head 408 is at station I. It is at such a time that the use of the wet cups is to be desired.

As to the other side of the control circuit of these two relays, a wire 685 extends from the terminal T-25 and is branched for connection to one terminal of each of the solenoids 415D and 416D, the other terminals of which are connected by wires 686 to line wire L-2. Similarly, the other contact of the control circuit of the relay WG-9 has its circuit extended from the terminal T-24 by a wire 687 to one terminal of each of the

solenoid

415W and 416W, the other terminals of which are connected by wires 683 to line wire L-2. Hence when a pickup operation is initiated in station I, the wet cups 410W are rendered effective, while such a pickup in station IV causes the dry cups 410D to be rendered effective Cycle timer relay R-1O The relay panel also includes a cycle timer relay R-lli that accomplishes two functions, one of which is concerned with the manual operation or selection and the other of which is concerned with the automatic operation of the machine. The relay R-lii has its operating coil connected across the Wires T-1 and T-2 that energize the motor 432 so that the relay R-lt) is energized whenever this motor is operated. The relay R-10 has a pair' of normally closed contacts, one of which is connected by a wire 69% to the terminal 661T so that it represents line wire L-2. The other of these contacts is connected by a wire 691 to the terminal T-26. As will be described hereinafter, this terminal 26 has its circuit extended to form a part of the running circuit of the operating motor 500M of the timer 500.

The relay R-IO also has a pair of contacts, one of which is connected by a wire 692 to line wire L-i, and the other one of these contacts which is the normally closed contact is connected by a wire 693 to the terminal T-ll5A.- This establishes a normal connection from the line wire L-l to the terminal T-A, but this connection is broken when the motor 432 is being operated and by breaking the circuit to terminal T-lSA, all of the manual control circuits that originate at this terminal are disabled when the column 401 is being rotated. Thus the manual drop circuit and the pickup circuits are disabled under suchcircumstances.

18 AUTOMATIC OPERATION As hereinabove pointed out, the cycle timer 500 serves as the primary control during operation of the entire system, and in association with the timer 5%, a terminal board 7% is provided having terminals Hi1 to 728 so arranged that opposed terminals are connected. The timer motor 500M is operated in such a way that after it has been manually started, it has a running circuit that may be interrupted to stop the timer while certain of the automatic operations are being performed, and whereby this circuit may finally be broken at the end of the complete cycle of operation of the timer 5%.

Thus, the terminal 701 represents line L-1, and is connected by a wire 730 to the common contact of the cam switch CS-28 of the timer, and from the normally closed contact of th-is switch a wire 731 extends to a terminal T-731. This circuit to line Wire L-l is utilized in running the timer 500 through an idle or run-out period during the drying cycle as will be described. It is from this terminal T-731 that one side of the circuit to the motor 500M is extended and this terminal is connected to line wire L-l by a wire 731B through the normally closed contacts of a disabling relay 502R.

The starter circuit for the motor 500M is provided by means including a relay 732 the operating coil of which has one terminal extended to a terminal T-732 from which a wire 733 extends to the terminal 702 which represents line wire L-Z. A terminal T-724 is connected by a wire 734 to the other terminal of the operating coil of the relay 732, and a wire 735 extends from the terminal T-724 to the terminal 724. A wire 736 includinga manual starter switch 737 is extended to the terminal 701 so that by the closing starter switch 737, the relay 732 may be operated.

The relay 732 is energized through the manual start switch 737, and when the relay is thus energized it closes normally open sets of contacts 732-1 and 732-2. The contacts 732-1 constitute the holding contacts of this relay and are connected respectively to the wire 734 and to the normally open contact of the cam switch CS-33. Thus when the timer is in its stopped relation at the end of its cycle, the normally open contact of the switch CS-33 is closed and the common contact is connected by a wire 740 to the terminal T-731 so that the holding circuit is established u'pon operation of the relay. The wire 740 is also connected by a wire 741 to one of the normally open contacts 732-2 which constitute temporary running contacts functioning in one side of the motor circuit until the cam switch CS-33 assumes control. The other one of these running contacts is connected by wire 742 to one terminal of the motor 500M, while another wire 743 connects this contact to the normally closed contact of the cam switch CS-33. Thus when the relay 732 is operated, a holding circuit is established, and circuit is established from the line wire L-l through the temporary running contacts of this relay to one terminal of the motor. Also, there is a holding circuit which is initially established through the normally open contact of the cam switch 08-33 which is then closed, but which is opened at the same time that the other or normally closed contact of switchCS-33 is closed, so as to thereafter provide a running circuit through the

wires

742 and 743, and which is continued throughout the cycle. Opening of this circuit by the cam switch 05-33 terminates the timer operation at the end of its cycle. At the time that the running circuit is established by the cam switch 05-33, the holding circuit for the relay 732 is broken so that this relay drops 19 wire 7 45 in a circuit that is closed during. operation of the timer 502..

In connection with such control of the cycle timer 500 by the drying timer 502 it should be pointed out that during the drying cycle, the cycle timer 500 is actually operated through an idle period which serves to run out a portion of the available time cycle of the cycle timer 500, thus, to enable the last operation of the mechanism to be initiated near the end 01": the complete cycle of the timer 550. Thus it is possible to reduce the running time of the timer Silt? after initiation of the final operation of cycle. Such idle running of the timer is accomplished by a cam switch (IS-28 which as above pointed out, is connected to theline wire and when closed, serves to extend circuit to the terminal T-731. Such circuit thusv providesa shunt around the disabling relaydiiZR. The cam switch CBS-28 is arranged to be closed soon after the initiation of the drying cycle and to be maintained closed for a. time period such that the remaining available timing operation of the timer- 500' is just slightly more thz'nr-v sufiicient to govern the automatic operations that are to take place after the conclusion of the drying cycle. This idle operation of the cycle timer 503' has been indicated in the timing diagram of Fig. 13.

The other side of the motor circuit of the motor 560M is extended to line wireL-Z and includes further disabling means so that motor 550M is stopped in. response to rotative movement of the, column 401 and also in response to downward displacement of the head 403. Thus, the other side of the motor circuit for the motor 560M is extended from its other terminal by wire 748 to the terminal 725, and a wire 74-9 extends this circuit to one of a pair of normally closed contacts of a disabling relay 750. The normally closed contact of this pair is connected by a wire 751 to the terminal 726 which is connected by a Wire 752 to the terminal T-26.

The disabling relay 750 has one terminal of its operating coil connected to line wire L-Z- while wire 753 extends to the other end of the side of the normally closed contact of the switch S-iiS, the common contact of which is connected by a wire 754 to line wire L4. Thus, when the head 408 is in its upper position so that the switch 8-405 is actuated, the line circuit for the disabling relay 750 is broken, but when the head 408 moves downwardly the switch 8-405 assumes its normally closed position so that the relay 750 is energized and remains energized'until the head 408 returns to its upper position.

- Thus the running circuit for the cycle timer motor 500M is automatically broken, during rotation of the column 401 and during pickup and drop operations of the head 408.

cam-oz connections for the cam switches As above pointed out, the automatic cycle of operation of the present installation is governed primarily by the timer 500, but the control of the cycle-timer 506 is superseded during the performance of certainof the functions that are involved. The automatic control that is exercised by the cycle-timer 500 is attained in certain respects by connecting selectedcam switches of this timer in parallel, across corresponding manual control switches that have been described hereinabove. Since certain of these functions are repeated during the machine cycle, but at different times in such cycle, two or more of the cam switches that operate at difierent times in the cycle are connected in parallel across certain of the manual control switches as will be described.

Automatic pickup Thus, theswitches 'CL-1, (58-14 and S- are allocated respectively to the initiation of the pickup funccan at stations I, IV and III, and it may be pointed out in the presen instance, that in practice the pickup function in stationIII is not used, and while connections to the switch C840 have been shown, has been done merely for illustration and actually these connections are removed in the performance of the typical cycle that is described. p

As to the switches" CS4, CS-14 and C8 20, the wires 20A are extended from the" common contacts of these switches to the terminal T-20. Similarly, wires 621A are extended from the normally closed contacts of the cam switches (IS-1, (IS-14 and CS-20 to the terminal 721 and a wire 721A extends from this terminal to the terminal T41. Thus the parallel circuits across the manual pickup switch PB-6 are provided.

Automatic drop Theinitiationfof the drop function has been allocated in the present instance to cam switches CS-"S, CS-16 and CS-ZZ that are each adapted to initiate the drop function at difierent times in the cycle at stations 11, III and IV, it being noted that the second dropping operation at station II is not used in the present instance, and has been shown merely for illustrative purposes.

Thus the common contacts of the switches CS-B. CS-16 and CS-ZZ are connected by wire 617A to the terminal 717 from which a wire 717A. is extended to the terminal T-17. three switches are connected by wire 618A to the terminal 718 from Whicha wire 718Ais, extended to terminal T-18. Thus, all of the cam switches: CS'-3, (IS-16 and CS+2Z are connected in parallel across the manual drop switch PB-S;

Automatic station selection As to the automatic station selection for the unit 22 under control of the cycle timer 500, a generally similar association of. the cam switches with the previously described manually controlled selection circuit is followed with the exception, however, that the selection of station IV is rendered dependent upon the cover 103 of the whirler being fully open.

In the automatic cycle that has been described, a single one of the cam switches is allocated to the selection of station I and thus, the cam switch 29 has its common contact connected by a wire 603A to the terminal 703 and a wire 703A is extended from this terminal to a wire 603, while the normally closed contact of the cam switch 0-29 is connected by a wire 610A- to the terminal 710 from which a wire 710A is extended to the wire 610. Thus, the cam switch 08-29 is connected in parallel across the push button switch PB-l, and when this cam switch is closed the selecting circuits areoperated to close the head 468 to be moved to station I'.

9am switches (ZS-15 and CS-21 are allocated to the automatic selection of station II although it may be pointed out that the switch C541 is not used in the cycle or operation that has been described, andis therefore disconnected in practice. Thus, thecommon terminals of the cam switches C8 15 and CS-Zi are connected by wires 615A to the normally closed contact of the other set of normally closed contacts of the disabling relay 750, the other contact of this set being connected by a wire 615C to the terminal 715. Such connection through the disabling relay is employed as a further safety measure to guard against column rotation while the head 408 is in a lowered position. The terminal 715 is connected by a wire 715A to the wire 692 which is of course connected to line wire TF1. This connection through normally closed contacts of the disabling relay 750 serves to disable the cam switches when the, head 408 is out of its upper position. The normally closed contacts of the'carn switches CS-15 and (IS-21 are. connected by wires 611A to the terminal 711 from which a wire 711A extends to the wire 611. These cam switches are thus placed in parallel across the manual selecting switch PB-Z and will produce similar operation. I

The norm-ally closed contacts of these- The cam switches CS-4 and CS4? are allocated to the selection of station III, although the cam switch CS-19 is not used in the presently described cycle and is, therefore, disconnected. These switches are connected parallel across the switch PB3, the common contacts thereof being connected to the wire 615A, while the normally closed contacts thereof are connected by a wire 612A to the terminal 712 from which a wire 712A extends to the wire 612. Thus, the switches CS-4 and 08-19 will produce the desired selection of station HI. As to the selection of station IV, the cam switches CS-2 and CS-13 are'employed respectively when the whirler is to be loaded and when it is to be unloaded.

The common contacts of these switches are connected by wires 609A to the terminal 709, and the wire 709A extends from this terminal to the wire 609. The normally closed contacts of the cam switch CS-2 and CS-13 are connected by wires 614A to the terminal 714, and a wire 714A extends to the wire 614. In this respect, it will be observed that this extends the circuit through the normally open contact of the switch S-108 so that the circuit is completed only when the whirler lid 108 has been opened so as to actuate and thus close the switch 108.

Starting and closing of whirler After a plate has been put in position on the whirler table and the head 408 has returned to station III, the rotative movement of the whirler table is initiated under control of the cam switch CS-S. The common contact of this switch is connected by a wire 730A to the wire 730 which extends from line wire L-1, while a wire 627A extends from the normally closed contact of this cam switch to the terminal 727. It might be noted that cam switch CS-17 is also allocated to the same function, but is not used except when the second coating arm 115-1 is being employed, and therefore, in the example described herein, the cam switch CS-17 is disconnected. The circuit is extended from the terminal 727 by wire 727A to terminal 827 in a motor starter 1278 that is associated with the whirler motor 127. The starter is arranged to connect lines L4 and L-3 to lines TT-l and TT-3 that extend to the motor 127, and the starter includes additional contacts 760 that are included in a holding circuit for the relay as will be described. Circuit is extended from terminal 827 by a wire 761 to one end of the operating coil of the starter relay, the other end of this coil being connected to line II. The holding circuit is provided by connecting the relay contacts 760 to the wire 761 and by connecting the other side of these contacts by a wire 763 to one terminal of the switch S-131. The other contact of this switch is connected by a wire 764 to a terminal 801 in the starter relay box and. this relay is connected by a wire 765 to line wire L-1. Thus, the holding circuit for the starter relay 1278 will be established as soon as the locking piston 131 of the whirler table has been withdrawn, and will be maintained until the locking plunger 131 has returned to its locking position at the end of the whirling cycle.

When the whirler motor 127 is energized, the movement of the lid or cover 108 toward its closed position is started, and to accomplish this, line wires TT-1 and T'I2 are also connected to the solenoid valve SV-108.

At the same time that the whirler motor relay 1278 is operated, the speed control lever 128L is started on its control movement between its zero position and its maximum position. This is done by energizing the solenoid valve SV-105. Thus, one side or terminal of the valve SV-105 is connected to terminal 802 which is in turn connected by a wire 768 to line wire L-2, then one terminal of the valve SV-108 is connected to terminal 816 which is connected by a wire 716A to the terminal 716 of the timer 500. A Wire 616A connects the terminal 22 A 716 to the normally closed contact of cam switch (ZS-12,- and the common contact of this switch is connected to the wire 730 so as to-be thus connected to line wire L-l. Thus the speed control lever is started toward its maximum position,and in the initial portion of this movement, it releases the switch S-128 so that it may assume its normal open condition. This is elfective to release air from the lock cylinder AC-131,-the control valve SV-131 of which is normally held open while the table is stopped. Thus one terminal of the solenoid valve SV-131 is connected by a wire 770 to the terminal 802 of the whirler starter relay box while the other terminal is connected through the terminal 832 by

wires

771 and 772 to one contact of the switch S428, the other terminal of which is connected to the terminal 801. Hence when the speed control lever allows the switch S428 to assume its open position, the valve SV-131 is de-energized and the lock plunger 131 is retracted. As the lock plunger 131 is retracted the switch S131 assumes its normal closed position so that the above described holding circuit is completed for the starter 1278.

Flushing and coating When the table is thus started, or soon thereafter, the timer 500 initiates the outward swinging movement of the coating arm as well as the flow of water to the discharge nozzle of the arm, and also initiates operation of the coating timer 501. Thus, the cam switch CS-7 initiates the outward swinging movement of the coating arm 115, and this cam switch is arranged to be closed for a period substantially longer than the maximum time required for the coating operation, the inward or return swinging movement of the arm being governed by the timer 501, as will be described.

It has been pointed out that the coating arms 115 and 115-1 may be used selectively, although in the present description the operation as to the coating arm 115 will be described in detail. Thus, two sets of controls are employed and may be rendered elfective selectively by a switch 775. This switch is connected inside to the line wire L-1 by a wire 776, and in one position it extends circuit to a wire 728 and in another position to wire 723. The wire 723 is associated with the cam switch controls for use when the coating arm 115-1 is being used, and these connections will not be described herein, particularly since they are similar to connections from the wire 728 that are used when the coating arm 115 is employed.

Thus the cam switch CS-7 has its common contact connected to the wire 728 and its normally closed contact is connected by a wire 605A to one of a pair of normally open contacts of a control relay 780, the other of the contacts of which is connected by a wire 605B to the terminal 705, a wire 705A being extended from this terminal to a terminal 805 in the whirler starter relay box. A wire 805A extends from the terminal 805 to one terminal of the solenoid valve SV-115, the other terminal of this valve being connected to terminal 802. Thus when the cam switch CS-7 is closed, the arm 115 will be moved outwardly and it should be noted that the control circuit extendsthrough the control relay 780 so that it may be broken 'by energizing the relay 780 when the coating arm 115 is to be returned to its normal outer position. This control is exercised by the coating solution timer 501.

The coating timer 501 has its operation initiated by the cam switch CS-8, the common terminal of which is connected to the wire 728. The other or normally closed terminal of this switch is connected by a Wire 781 that extends to one terminal of the motor 501M, and to the common contacts of control switches 5011 and 50 1-2 that are diagrammatically shown as being embodied in this timer. The other terminal of the motor 501M is connected by a wire 782 to terminal 702 which constitutes line wire L-2. The closure of the cam switch