US3508711A

US3508711A - Fluid dispensing system

Info

Publication number: US3508711A
Application number: US694474A
Authority: US
Inventors: Thomas G Switall
Original assignee: Ryco Graphic Manufacturing Inc
Current assignee: Technotrans America Inc
Priority date: 1967-12-29
Filing date: 1967-12-29
Publication date: 1970-04-28
Anticipated expiration: 1987-04-28

Description

A ril 28, 1970 Filed Dec. 29, 1967 T. G. SWITALL FLUID DISPENSING SYSTEM 3 Sheets-Sheet i April 1970 T. c5. SWITALL FLUID DISPENSING SYSTEM 3 Sheets-Sheet 2 Filed Dec. 29. 1967 T. G. SWITALL 3,508,711

FLUID DISPENSING SYSTEM 3 Sheets-Sheet 5 myif' ZFccZe (c6 0 aenzaa ,521/

April 28, 1970 I Filed Dec. 29. 1967 i Q... M E 1 w a i: l 5W ww $0 m w .w

3,508,711 Patented Apr. 28, 1970 3,508,711 FLUID DISPENSING SYSTEM Thomas G. Switall, Niles, Ill., assignor to Ryco Graphic Mfg., Inc., Chicago, 111., a corporation of Illinois Filed Dec. 29, 1967, Ser. No. 694,474 Int. Cl. A62c 37/20 U.S. Cl. 239562 11 Claims ABSTRACT OF THE DISCLOSURE A valve within a manifold chamber is operated by means responsive to the fluid pressure within the chamber. The pressure within the chamber is controlled by adjustable means operable in one position of adjustment for placing a pressurized fluid source in communication with the manifold and operable in another position for interrupting the fluid communication between the manifold and the pressurized fluid source and for releasing the fluid pressure within the manifold. The adjustable means is preferably a flexible member disposed within a vessel and movable between two positions by means controlling the pressure within the vessel. The flexible member controls a valve and is in fluid communication with the manifold. When the vessel is pressurized, the flexible member is compressed, and the valve is opened to pressurize the manifold, and when the pressure is released within the vessel, the flexible member expands to close the valve and release the pressure within the manifold.

BACKGROUND OF THE INVENTION This invention relates to an improved, accurately controlled fluid dispensing system and more particularly to a system for dispensing a liquid under pressure and preferably in the form of a spray from valved nozzles in a manner which will permit immediate liquid discharge from the nozzles when the system is turned on and will prevent leakage from the nozzles when the system is turned off.

This invention has particular application to an apparatus for spraying a cleaning solvent onto the blanket cylinders of a web offset printing press to effect the removal of lint and ink therefrom as a web of paper is being run through the press. It will be understood, however, that the invention will have other applications, and while it may be described in connection with a device for cleaning the blanket cylinders on a web offset printing press, the invention is not limited to this particular application.

The blanket cylinders on an offset press must be periodically cleaned in order to remove the lint, dust and ink buildup thereon. To avoid stopping the press and washing off the blanket cylinders with a solvent soaked rag, a procedure has been devised whereby the cleaning may be accomplished safely without shutting down the press. In this procedure a solvent is sprayed onto the blanket cylinders and onto the paper web While the press is running. The spray head is mounted in fixed position with respect to the cylinders that the cleaning may be accomplished by merely turning on the solvent. However, after the cleaning operation has terminated and the solvent has been turned off, it is essential that there be no discharge whatsoever from the spray nozzles onto either the press or the paper web.

A system constructed in accordance with the present invention will permit the spraying of a fluid such as a cleaning solvent under pressure while providing a means for positively shutting off all discharge from the spray nozzles at the end of the cycle or process. The system eliminates the need for solenoid valves which are expensive and which under certain conditions with certain solvents could be dangerous. The shut off valve or valves are placed at or adjacent to the discharge ports or spray nozzles, and by reducing the pressure in contact with the valves when they are closed, there is little tendency for leakage. The liquid, however, remains in contact with the valves so that spraying will begin immediately when the system is turned on.

SUMMARY OF THE INVENTION In accordance with one embodiment of the invention, the fluid dispensing system comprises a manifold spray head or chamber having a number of nozzles along one side thereof, the discharge through each nozzle being controlled by means of an individual nozzled valve. Each nozzle valve has a valve operating member movable between an open and a closed position for controlling the fluid discharge through the valve and its associated nozzle. Pressure-responsive means within the manifold chamber in association with each vave operating member is effective to move the member to its open position only when the fluid pressure within the manifold chamber rises above a predetermined value.

A control unit is mounted in fluid communication with the manifold chamber, and means is provided for delivering fluid under pressure in excess of the aforementioned predetermined value to this control unit. The control unit includes adjustable means operable in either of two alternative positions. In one position the control unit means is effective for placing the fluid delivery means in fluid communication with the manifold chamber so that the chamber may be pressurized to effect opening of the nozzle valves therein. The control unit adjustable means is operable in its other position for interrupting the fluid com munication between the fluid delivery means and the manifold chamber and for releasing the fluid pressure in the manifold chamber, 50 that the nozzle valves may be closed.

The pressure responsive means associated with each valve operating member preferably includes means defining a flexible subchamber within the manifold chamber, the subchamber being resiliently compressible upon the application of a fluid pressure within the manifold chamber. The valve operating member is attached to a wall of the subchamber and is movable into and out of engagement with its valve seat as the subchamber is respectively expanded and compressed.

The control unit for controlling the fluid pressure within the manifold chamber preferably includes a Vessel having an expansible and contractible receptacle sealingly disposed therein, the receptacle being in fluid communication with the manifold chamber. Means is provided for controlling the pressure within the vessel exterior of the receptacle for effecting expansion and contraction of the receptacle therein. Valve means within the receptacle is operable in response to contraction of the receptacle within the vessel for placing the fluid delivery means in fluid communication with the interior of the receptacle, and this valve means is operable in response to expansion of the receptacle within the vessel for interrupting the flow of fluid from said delivery means into the receptacle. The receptacle is so constructed that after the valve means therein has been turned off, further expansion of the receptacle will relieve the fluid pressure therein with consequent relief of pressure within the manifold chamber which is in fluid communication therewith.

DESCRIPTION OF THE DRAWINGS FIGURE 1 is a perspective view of a portion of the apparatus constructed in accordance with this invention showing the manner in which the apparatus may be employed in the cleaning of a set of blanket rolls of a web offset printing press;

FIG. 2 is a schematic illustration of a system constructed in accordance with this invention;

FIG. 2A is a schematic illustration of a system having modified means for controlling the fluid pressure to the manifold chamber;

FIG. 3 is an enlarged fragmentary sectional elevational view of one of the manifold chambers partially in section to show one of the nozzle valves in a closed condition;

FIG. 4 is a sectional elevational view of a portin of the manifold chamber showing one of the nozzle valves in an open condition;

FIG. 5 is an enlarged sectional elevational view of one of the control units and a portion of one of the manifold chambers showing the control member conditioned to effect pressurization of the manifold chamber; and

FIG. 6 is an enlarged sectional elevational view of the control unit conditioned to effect release of the fluid pressure within the manifold chamber.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The fluid dispensing system 10 constructed in accordance with this invention is adapted to be used with a web offset printing press 12, a portion of which is schematically illustrated in FIG. 1. As shown, a web of paper 14 is moved through the press in the direction of the arrow between a pair of blanket cylinders 16 and 18. Ink is transferred from a reservoir 19 to an ink roller 20 and thence onto a plate cylinder 21 for transfer to the upper blanket cylinder 16. In like manner ink is taken from a reserovir 22 onto an ink roller 23 which transfers it to a plate cylinder 24 and thence onto the lower blanket cylinder 18. In order to effect cleaning of the blanket cylinders, it is found desirable to spray a. solvent onto the paper web and blanket cylinder on the upstream side thereof as the cylinders are rotating and as the paper web is moving through the press. Although only one set of cylinders is shown in FIG. 1, the press usually employs several sets of cylinders, and for each set there will be a spray head manifold 26 for the upper blanket cylinder 16 and another spray head manifold 28 for the lower blanket cylinder 18.

A complete fluid dispensing system 10 is schematically illustrated in FIG. 2. The illustrated apparatus includes two spraying units, one for each bank or set of cylinders to be cleaned. Each spraying unit consists of the aforementioned pair of

manifold spray heads

26 and 28, a liquid control unit 30 and a regulating means 32 for controlling the operation of the liquid control unit 30. In this embodiment the air is supplied through main air line 34 for operation of an air motor 36 attached to a drum 38 containing a liquid such as a liquid cleaning solvent. The pump 36 delivers the liquid under pressure through a conduit 40 to the individual control units 30 which control the flow of liquid to their respective

spray head manifolds

26 and 28.

The spray head manifolds 26 and 28 are identically constructed, each consisting of an elongated hollow tubular bar which carries a plurality of spray nozzles 42 at one side. The spray nozzles are individually operated in response to fluid pressure within the spray head manifold. As best illustrated in FIGS. 3 and 4, each nozzle 42 has a discharge port 420 at the upper end of which is a valve seat 44, a valve member 46 having a needlelike tip or end portion 46a is movable between a closed position as illustrated in FIG. 3, wherein the tip 46a seats and sealingly engages the valve seat 44, and an open position as illustrated in FIG. 4, wherein the tip 46a is withdrawn from the valve seat 44 and liquid is permitted to flow from the interior of the spray head manifold through the port 42a of the nozzle 42.

Mounted within an aperture 48 in the side of the manifold opposite each nozzle 42 is a pressure-responsive device 50 which defines a sealed subchamber within the manifold chamber. The pressure-responsive device 50 comprises a substantially cylindrical outer sleeve portion 52 having a flange 52a at its outer end. The flange 52a seats against an O-ring 54 which rests on and seals against a shoulder 53 within the aperture 48, and a closure plate 56 overlies the flange. The remainder of the sleeve portion 52 extends into the interior of the manifold spray head toward the nozzle 42. A snap ring 58 which engages in a peripheral recess in the aperture-defining portions of the manifold holds the closure plate 56, the sleeve portion flange 52a and the sealing O-ring 54 in place within the aperture 48.

Forming an integral part of the pressure responsive device 50 and disposed for movement within the cylindrical sleeve portion 52 of the device is a cup portion 60 having substantially cylindrical side walls 60a and a flat disclike bottom 60b. The cylindrical walls 60:: of the cup portion 60 are sealingly connected to the outer sleeve portion 52 by means of a flexible bellowslike web portion 62. The sealed, integral construction of the pressure-responsive device 50, including the outer sleeve portion 52, the flexible web portion 62 and the cup portion 60, is such that no fluid, such as liquid solvent, may pass from the manifold into the interior of the device. However, the interior of the device 50 is vented to the atmosphere through the aperture 56a in the closure plate 56. The valve operating member 46 is aflixed to the bottom of the cup portion 60 and is movable with the cup portion from a closed position illustrated in FIG. 3 to an open position illustrated in FIG. 4 in response to the appli cation of fluid pressure within the spray head manifold 26. A coil spring 64 is disposed within the cup 60, and the strength of the spring will determine the amount of fluid pressure within the manifold that is necessary to elfect opening of the nozzle valve. Thus, fluid discharge from any of the nozzles 42 within the spray head manifold is governed by the fluid pressure within the manifold.

If it is desired to maintain any one of the valves in a closed or inoperative position while operating the other valves in the spray head manifold, this may be accomplished by means of a turnoff member 66 having a threaded shank 66a and a knob 66b. The shank 66a is threaded into the closure plate 56. The knob 66b and shank 66a may be rotated to advance the lower end of the shank into engagement with the bottom of the cup portion 60 of the pressure-responsive device 50, thereby preventing the cup portion and the valve operating member 46 attached thereto from moving away from the valve seat 44 to open the nozzle valve. The nozzle valve will thus remain in a closed position regardless of the pressure within the spray head manifold 26. The nozzle valve may be placed back in operation for response to pressure within the manifold by merely rotating the knob 66b in the opposite direction until the lower end of the shank 66a is a suflicient distance from the bottom 60b of the cup to permit the valve opening movement of the cup portion 60 and of the valve operating member 46.

The control unit 30 for controlling the fluid pressure within the

spray head manifolds

26 and 28 in best illustrated in FIGS. 5 and 6. The control unit 30 comprises a closed vessel 66 defining a rigid outer chamber and having a smaller expansible and contractible member or receptacle 68 disposed therein and defining a flexible inner or subchamber. The member 68 has a flat disclike end portion 68a and a flexible bellowslike, substantially cylindrical wall 68b. The open end of the receptacle 68 is sealed to one wall of the vessel 66 so that the receptacle 68 may hold fluid such as liquid solvent under pressure. A conduit 70 places the interior of the receptacle 68 in fluid communication with the two manifold spray heads 26 and 28.

Disposed within the interior of the receptacle 68 is a valve 72, which in the embodiment illustrated in FIGS.

and 6 is a ball valve having a body portion 74 in the interior of which is a chamber 74a. A ball 76 is disposed within the chamber 74a and is movable between a closed position as illustrated in FIG. 6 and an open position as illustrated in FIG. 5. A spring 77 urges the ball toward its closed position in engagement with a valve seat 74b at the upper end of the chamber 74a. The ball may be forcibly moved to its open position out of engagement with the valve seat 74b, thereby opening the valve and permitting fluid from within the valve to pass outwardly through the ports 74c at the top of the valve.

For this purpose a central opening 74d is provided at the top of the valve and attached to the flat disclike end portion 680 of the member 68 is a pin 78 which moves with the end portion 680 from a position removed from the valve, as illustrated in FIG. 6, into a position within the valve, as illustrated in FIG. 5. When the pin 78 is disposed within the valve, it engages the ball 76 and moves the ball away from the valve seat 74b, thereby opening the valve. A conduit 80 places the interior of the valve in fluid communication with the pressurized fluid in the conduit 40 (see FIG. 2).

Expansion and contraction of the receptacle 68 within the vessel 66 is regulated by means 32 which controls the pressure within the vessel 66 surrounding the receptacle 68. The means 32 preferably includes an air line 82 connecting the vessel 66 to the air supply line 34 through a three-way valve 84 having an exhaust port 84a. The three-way valve 84 is preferably a standard solenoid valve operated through a control switch 85. Briefly, the valve 84 has a member which is reciprocally movable between two positions. In one position the inlet and exhaust ports of the valve are in communication permitting air under pressure to pass from line 34 through the line 82 and into the interior of the vessel 66 surrounding the receptacle 68. In the other position of the air valve member, the outlet and exhaust ports of the valve are in communication, and, thus, the interior of the vessel 66 surrounding the receptacle 68 is exhausted to the atmosphere.

The air pressure in the line 34 may be on the order of between 80 and 125 p.s.i., and the pressure of the fluid or liquid solvent in the supply line 40 is preferably on the order of about 60 p.s.i. The air pressure must exceed the liquid pressure by an amount sufficient to permit the receptacle 68 to be contracted to and held in the position illustrated in FIG. 5 against the resistance of the liquid pressure and the pressure of spring 77. The nozzle valves are adapted to open under a liquid pressure of somewhat less than 60 p.s.i., preferably opening at between about 30 p.s.i. and 40 p.s.i.

In operation, the air pressure is turned on actuating the pump 36, and a fluid pressure of 60 p.s.i. is developed in the liquid supply line 80. The valve 72 in each liquid control unit 30 is normally closed with the ball 76 seated against the valve seat 74b, and the air control valve 84 is normally closed to exhaust the interior of the vessel 66 to the atmosphere as illustrated in FIG. 6. In order to initiate spraying, the air valve 84 is opened, either mechanically or electrically, closing the exhaust port 84a, and air under pressure flows through the line 82 into the interior of the vessel 66 surrounding the receptacle 68. This causes the receptacle 68 to axially contract to the position illustrated in FIG. 5 wherein the pin 78 enters the valve opening 740! and engages the ball 76 to open the valve 72. Fluid under pressure will flow through the valve and outwardly through the porth 74c into the interior of the receptacle 68 and thence outwardly through the conduit 70 to the

spray head manifolds

26 and 28. The fluid pressure within the spray head manifolds will increase and will ra idly overcome the resistance of the springs 64 in each of the valve operating members 50. Each cup portion 60 in response to this pressure will move away from its associated nozzle 42, carrying the valve-operating member 46 away from the valve seat 44 in each case, thereby permitting the liquid to be discharged as a spray from the nozzles 42. The valve-opcrating members 46 will remain withdrawn from their valve seats, and spraying will continue so long as the pressure within the spray head manifold remains high enough to overcome the resistance of the springs 64.

In order to stop the spraying operation, the air valves 84 are moved to their closed positions thereby exhausting the interior of the vessels 66 to the atmosphere. The pressure within each receptacle 68 thus becomes larger than the pressure surrounding this receptacle, and the receptacle expands withdrawing the pin 78 from the valve 72 permitting the valve to close. The receptacle 68 continues to expand, releasing the fluid pressure within this receptacle and within the conduit 70 and the manifold spray heads 26 and 28 which are in fluid communication therewith. As the liquid pressure falls below the level suflicient to overcome the resistance of the springs 64, the springs 64 become effective to move the valve operating members 46 into engagement with their valve seats 44, shutting off all fluid flow through the nozzles 42. It is preferred that the expansion of the receptacle 68 in the control unit 30 be limited to axial expansion and that such expansion be otherwise unrestricted so that in the off or closed position, there will be little or no pressure within the

spray head manifolds

26 and 28, thereby eliminating any tendency toward dripping from the valved nozzles. This is a particularly important feature for any unit used for cleaning the blanket cylinders in an offset press.

An alternative fluid system and control for the

spray head manifolds

26 and 28 is illustrated in FIG. 2A. This system includes a main supply line carrying liquid solvent from a supply tank, a return line 92 for returning solvent to the supply tank and a pair of three-way valves 94 and 96 for controlling the application of fluid under pressure to the

spray head manifolds

26 and 28 respectively. The valve 94 is illustrated in a position wherein the liquid solvent under pressure is permitted to flow from the supply line 90 through the valve to the spray head manifold 26. The valve 96 on the other hand is illustrated in the position wherein the liquid solvent under pressure is prevented from flowing from the supply line 90 through the valve and into the spray head manifold 28, and, instead, the spray head manifold is placed in fluid communication with the return line 92, thereby relieving the pressure in the spray head to close the nozzle valves in the spray head manifolds. In practice, of course, the valves 94 and 96 would be operated together so that in corresponding positions, the spray heads 26 and 28 would be operated together. If desired the two spray head manifolds may be operated by means of a single control valve as in the preferred embodiment of FIG. 2. The control valve or valves 94 and 96 may be solenoid operated and controlled by means of a switch 98.

-.T he systems of FIGS. 2 and 2A both employ the same construction for the spray head manifolds including the pressure actuated valves, and both systems provide for the release of pressure in the spray head manifolds when the system is not in operation, thereby avoiding any dripping from the nozzles 42.

It is to be understood that the present disclosure has been made only by way of example and that many additional modifications, changes, and various details may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.

What is claimed is:

1. A fluid dispensing system comprising a chamber, a valve having a member movable between an open and a closed position for controlling fluid discharge from said chamber, pressure-responsive means connected to said valve member and effective to move said valve member to its closed position only when the fluid pressure within said chamber falls below a predetermined value, a control unit in fluid communication with said chamber, means for delivering fluid under pressure in excess of said predetermined value to said control unit, said control unit including a vessel, means dividing said vessel into two isolated variable volume sections, means for controlling the pressure within one of said sections to effect contraction and expansion of the other of said sections, the other of said sections being in fluid communication with said chamber, and valve means responsive to the contraction of said other section for placing said fluid delivery means in fluid communication with the interior of said other section and responsive to the expansion of said other section to interrupt the flow of fluid from said delivery means into said other section.

2. The structure of claim '1 wherein said chamber is an elongated tubular member and a plurality of valves are disposed therein, each valve having an associated pressure-responsive means for eifecting the opening and closing thereof, whereby all valves may be opened and closed substantially simultaneously and will remain open only so long as the fluid pressure within said tubular member is maintained above said predetermined value.

3. The structure of claim 1 wherein means is provided for manually locking said valve in a closed condition independently of the pressure condition Within said chamher.

4. The structure of claim 1 wherein said pressureresponsive means includes a resiliently compressible member.

5. The structure of claim 1 wherein said pressureresponsive means includes means defining a resiliently compressible subchamber sealingly disposed within said chamber, the interior of said subchamber being vented to the atmosphere.

6. The structure of claim 1 wherein said valve includes a valve seat at one side of said chamber and a movable valve-operating member, and said pressure-responsive means includes an outer sleeve portion sealingly disposed against and extending from the opposite side of said chamber toward said valve seat, a cup portion mounted for movement within said sleeve portion toward and away from said valve seat, the bottom of said cup being disposed toward said valve seat, a flexible portion sealingly connecting said cup portion to said sleeve, said valveoperating member being connected to said cup portion bottom and being movable with said cup portion between its open and closed positions with respect to said valve seat.

7. The structure of claim 6 wherein spring means at least partially disposed within said cup portion acts against said chamber opposite side to resiliently urge said cup portion and said valve-operating member toward said valve seat to close said valve.

8. A fluid dispensing system comprising a chamber, a valve within said chamber, said valve having a member movable between an open and a closed position for controlling fluid discharge from said chamber, pressureresponsive means within said chamber connected to said valve member and effective to move said valve member to its open position only when the fluid pressure within said chamber rises above a predetermined value, a control unit in fluid communication with said chamber, means for delivering fluid under pressure in excess of said predetermined value to said control unit, said control unit including a vessel, an expansble and contractable recep tacle sealingly disposed within said vessel and dividing the vessel into two isolated sections, the interior of said receptacle being in fluid communication with said chamber, means for controlling the pressure within said vessel on the extrior of said receptacle for eflecting expansion and contraction of said receptacle, and valve means responsive to the contraction of said receptacle for placing said fluid delivery means in fluid communication with the interior of said receptacle and responsive to the expansion of said receptacle to interrupt the flow of fluid from said delivery means into said receptacle.

9. The structure of claim 8 wherein said valve means is responsive to the contraction of said receptacle for placing said fluid delivery means in fluid communication with the interior of said receptacle and is responsive to the expansion of said receptacle to interrupt the flow of fluid from said delivery means into said receptacle.

10. The structure of claim 8 wherein said means for controlling the pressure within said vessel includes a pressurized gas source and a three-way valve, said threeway valve being operable in one position to permit the flow of gas from said source into said vessel to pressurize the interior of the vessel, and being operable in another position to prevent the flow of gas from said source into said vessel and to vent the interior of said vessel.

11. The structure of claim '8 wherein said valve means includes a valve seat and a valve member movable with respect to said valve seat between an open and a closed position, said receptacle carrying means thereon for engaging and effecting movement of said valve member to an open position when said receptacle is in its contracted position.

References Cited UNITED STATES PATENTS 2,030,143 2/1936 Geiger-Knusli 222r497 X 2,699,968 1/1955 Meyer 239566 X 3,012,700 12/1961 Mayer 222-504 X 3,053,419 9/1962 Palmer 222-504 X 3,214,102 10/1965 Meyer 239566 X 3,249,305 5/1966 Baker 239566 X 3,027,905 4/1962 Dobrikin 137-495 X 2,188,676 1/1940 Crandall 222250 3,344,960 10/1967 Jacobs 222335 ROBERT E. REEVES, Primary Examiner H. S. LANE, Assistant Examiner US. 01. X.R.