Abstract: Systems and method for delivering materials to a tool are disclosed. A material delivery system utilizes two or more sources of the material to be delivered to the tool. One or more of the sources of the tool may be a batch mixer. The material delivery system also includes at least two material delivery recirculation lines providing material to at tool. The material delivery system may be manually or automatically controlled to switch supply of the material from one source to another, and/or to switch from one material delivery recirculation line to another.

Abstract: A food dispensing machine includes a product chamber with a dispensing valve connected to the product chamber and having an outlet through which a product contained in the product chamber is dispensed. The product chamber has a cleaning solution inlet connectable to a cleaning solution supply source for receiving cleaning solution into the product chamber. The product chamber further has an ingredient inlet alternatively connectable to either an ingredient supply source or the dispensing valve outlet. When the ingredient inlet is connected to the dispensing valve outlet, a re-circulating flow path is created, allowing for complete cleaning and sanitizing of the product flow path.

Abstract: A grease gun with a pressure-relief device comprises a pressure-relief device. When the grease gun is subjected to an excessive driving force, the pressure-relief device will be pressed to allow the valve member of the pressure-relief device to compress the spring toward the cover member, and then the grease-passage port and the cartridge port will communicate with each other, so that the grease can flow back into the grease cartridge to further control the pressure in the grease gun, thus avoiding the damage to the grease gun and further extending the service life of the grease gun.

Abstract: A dispensing system for an appliance has a main tank for holding a fluid. The main tank controls the temperature of the fluid. A dispenser outlet fluidly is connected to the tank by a dispenser fluid line. An auxiliary tank holds a volume of the fluid. A flow control device selectively moves the fluid held in the auxiliary tank to the main tank then through the dispenser fluid line to the dispenser outlet and selectively removes the fluid remaining in the dispenser fluid line after dispensing.

Abstract: A combination dispense and recirculation valve assembly is disclosed for viscous fluids. The assembly easily moves between a dispense and a recirculation position. Therefore, a pump linked to the canister of fluid being dispensed can be run continuously, intermittently or on demand. After the dispense, the actuator moves the valve stem downward to block any further dispense and the pump recirculates fluid upward past an upper valve element and upper valve seat into a recirculation outlet and back into the canister. In the closed position, the valve chamber is sealed to prevent air from causing any remaining colorant to dry. When a dispense is desired, the actuator simply raises the valve stem upward so the upper valve element engages the upper valve seat thereby preventing fluid from being recycled and directing all fluid downward past the lower valve element and out through the nozzle.

Abstract: A container is provided comprising a receiving vessel (12) and an outlet part (14), wherein the outlet part (14) comprises a one-way valve (24) and at least one bypass passage (32) bypassing the one-way valve (24), wherein the outlet part (14) is at least partly movable with respect to the receiving vessel (12) between a closed position and an opened position, wherein in the closed position the receiving vessel (12) seals the bypass passage (32) and in the opened position the receiving vessels (12) unseals the bypass passage (32). Due to the one-way valve (24) of the alternative container (10) the filling is facilitated without complicating emptying, since it is prevented that the content (42) of the container (10) flows back accidently.

Abstract: An installation for packaging a product in receptacles. The installation includes a series of filler stations each having a filler spout having a spout body with a top end connected to a filler spout feed duct and a bottom end provided with an orifice fitted with a controlled valve. The filler spout is fitted with a looping duct opening into the spout body above the controlled valve and connected by a link member to a general feed duct at a point between a stop valve and an isolation valve. A purge valve is connected to the general feed duct between the isolation valve and the link member.

Abstract: A chemical liquid supply device applies chemical liquid from a nozzle to a processed object. The nozzle is provided in a moving head, which reciprocates between an applying position and a waiting position and includes an application valve operating so as to take an applying state of applying the liquid from the nozzle and a stopped state of stopping the application. Chemical liquid is pumped from a tank through a filter to a valve chamber of the application valve via a supply tube. The valve chamber is connected to a buffer tank through a circulation tube. The circulation tube is provided with a circulation valve for opening/closing its flow path.

Abstract: A water-dispensing appliance is provided, in particular for dispensing drinking water, comprising a water inlet which can be connected to a water-supply device, also comprising a dispensing device with a water outlet, via which water can be dispensed from the appliance, the dispensing device being connected to the water inlet via a main line which has a downstream portion and an upstream portion, and also comprising a water heater. The water-dispensing appliance has a return line, of which the start is line-connected to the downstream portion of the main line and the end is connected to the upstream portion of the main line, and the appliance also has a delivery unit in order for water heated up by means of the water heater to be delivered through the main line from the upstream portion to the downstream portion.

Abstract: An automated apparatus, recipe based C.A.R.C. paint batch mixing system and method for mixing two or more water based or waterborne chemical agent resistant coating materials, primarily designed to meet military specification number MIL-DTL-64159. Once homogeneously dispensed and mixed in the desired recipe quantity, the operator removes the batch mixed material and applies the material to a substrate using various types of application methods. The complete apparatus is designed as a modular configuration, allowing for a reduced footprint and quick assembly.

Abstract: A process for the production of alumina trihydrate by alkaline digestion of bauxite using the Bayer process in which aluminate liquor and insoluble residues are separated using a solid/liquid separation device (E; W2; DC) characterised in that the said slurry (21a; 41; 230?) is at least partially passed through a hydrocyclone (H1; H21; H22; H3) to improve and accelerate the separation of the sodium aluminate liquor from the insoluble residues in the slurry (21a; 41; 230?) containing the said liquor and the said residues and that supplies or is derived from the said liquid-solid separation device. In a first embodiment, at least one hydrocyclone is used at the upstream side of the settler-thickener, as clarifier of the pregnant liquor. In a second embodiment, at least one hydrocyclone is used as a thickener of insoluble residue mud. In a third embodiment, a hydrocyclone is used in combination with the causticisation settler.

Abstract: A microdosing device for a liquid medium includes a dosing compartment and an electrically or electronically activatable vibration unit which can cause at least one contact area of the dosing compartment to vibrate for the delivery of a volume of medium. A medium reservoir is connected to the dosing compartment by at least one flow channel. A manually operable conveyance device for conveying medium to the dosing compartment and/or for conveying medium back from the dosing compartment to the medium reservoir is assigned to the at least one flow channel.

Abstract: Apparatus for storing water, especially purified water, for use in a beverage dispenser is provided with a microbiological agent to kill or deter microbiological growth and maintain the quality of the water. The agent is provided in a physical form to promote contact with the water and may be renewable to maintain effectiveness of the agent over a period of time. In one arrangement, the agent is contained in a cartridge 92 arranged in a re-circulation loop 89 through which the water in a reservoir 80 is passed and returned to the reservoir 80. The cartridge 92 and/or a carrier for the agent within the cartridge 92 may be replaceable to renew the agent. The agent may also be provided within the reservoir 80 and various arrangements for this are also disclosed.

Abstract: A system and method for mixing and dispensing two substances are provided. The system includes: a first substance a first container for containing a first substance, a second container for containing a second substance, a feeding tube, and a pumping system connected to the first container, the second container, and the feeding tube; wherein the system comprises at least three modes of operation: combining the first and second substances into one combined substance, mixing the combined substance, and dispensing the mixed substance; and wherein the pumping system is adapted to perform the at least three modes of operation and dispense the mixed substance to the feeding tube.

Abstract: Apparatus for storing water, especially purified water, for use in a beverage dispenser is provided with a microbiological agent to kill or deter microbiological growth and maintain the quality of the water. The agent is provided in a physical form to promote contact with the water and may be renewable to maintain effectiveness of the agent over a period of time. In one arrangement, the agent is contained in a cartridge 92 arranged in a re-circulation loop 89 through which the water in a reservoir 80 is passed and returned to the reservoir 80. The cartridge 92 and/or a carrier for the agent within the cartridge 92 may be replaceable to renew the agent. The agent may also be provided within the reservoir 80 and various arrangements for this are also disclosed.

Abstract: A beverage filling method and an apparatus to perform the beverage filling method, wherein a liquid is delivered from a storage tank into a filler tank of a filler, and the liquid is filled into containers by the filler. The method is characterized in that the liquid in the filler tank is returned through return piping attached to the filler tank and refluxed to the storage tank through a reflux path. According to this method, an excess of liquid in the filler can be circulated throughout the entire line.

Abstract: In application of a foamed hot melt adhesive, a mixing ratio of foam can be selectably and quickly set, and also application of a foamed hot melt adhesive and that of a solid hot melt adhesive can be selectively performed by a single application device. A first gear pump and a second gear pump are driven by drive mechanisms independent from each other. The pressure of a liquid being sent by the pressure in the second compression process is detected, and this causes the speed of the first gear pump and the second gear pump to be sequence-controlled to automatically control the amount of mixing of gas. A gas suction opening is provided between the first gear pump and the second gear pump, and a mixer is provided between the gas suction opening and the second gear pump. The end of a return circuit is set on the downstream side of the first gear pump to prevent foam from returning to the tank side. A restriction valve is installed in a gun to produce a single bubble.

Abstract: A heated air manifold of reduced physical dimensions for heating process air for use in dispensing heated liquids, such as hot melt adhesives. The heated air manifold includes at least one heating element and an air plenum having an air inlet and an air outlet. The dimensions of the air plenum are optimized for providing a compact heated air manifold for use in various adhesive dispensing systems, such as systems assembled from modular adhesive manifold segments, while retaining the ability to heat the process air in the air plenum to a desired application temperature. The heated air manifold may include a thick film flat heater disposed in the air plenum. The air plenum may have multiple individual segments winding throughout the volume of the heated air manifold.

Abstract: A water purification apparatus having an inlet and an outlet, and at least one water purification device thereinbetween, wherein the outlet includes at least a first and second water release valve, the first release valve being operable at a first flow rate, and the second release valve being operable at a second flow, is described. Preferably, at least one water release valve is operable at a relatively slow flow rate of generally up to 0.1 liter per minute, and at least one other water release valve is operable at a relatively fast flow rate of, for example, up to 2 liters per minute. The present water purification apparatus provides the operator with the ability to very accurately obtain an exact volume of water desired.

Abstract: A furnace flow control valve for use within a bath of molten metal. The flow control valve includes a vertically-disposed elongated tubular stator, which is configured to receive flow from a molten metal pump. The valve has a rotor which is sealing rotatable within the stator between: a full re-circulation position, where flow from the pump passes un-hindered through the valve; a full transfer position, where flow from the pump is redirected into the vertically disposed stator and out of the valve; and a partial re-circulation/partial transfer position where flow from the pump both passes through the valve and is transferred up and out of valve through the stator.

Abstract: A dispensing apparatus is disclosed. The dispensing apparatus has a product container for holding the fluid; a chamber including a dispensing cylinder having an inlet and an outlet; an inlet check valve disposed at the inlet of the chamber, the inlet check valve being openable to permit flow substantially only in a direction through the inlet check valve into the chamber; an outlet check valve disposed at the outlet of the chamber, the outlet check valve being openable to permit flow substantially only in a direction from the chamber out through the outlet check valve; an outlet spout connected with the outlet of the outlet check valve for receiving the fluid from the outlet check valve; a spring-biased piston configured for sliding movement in the dispensing cylinder, the piston being smaller than the dispensing cylinder thus providing a clearance; and a bypass backflow opening disposed in the dispensing cylinder above the spring-biased piston.

Abstract: A portable fluid-storage container is disclosed that allows for a selected material to be stored and dispensed at a location where the fluid is needed. The portable fluid-storage container may further condition the fluid to ensure proper characteristics even after prolonged periods of storage, preferably with reduced waste.

Abstract: A dispense apparatus and system for dispensing suspensions or emulsions. The system ensures uniformity of distribution of the dispersed phase within the continuous-phase liquid by moving the fluid through the dispense cartridge, such as with a continuous or pulsating flow. In one embodiment, peristaltic pumps are positioned upstream and downstream of the dispense cartridge, in fluid communication with and forming a single loop with a fluid source. Circulation between the fluid source and the dispense cartridge is maintained. In a second embodiment, a pump circulates fluid into and out of the dispense cartridge and is also in fluid communication with a fluid source such as with a pinch valve to allow proper filling of the dispense cartridge from the fluid source. In a third embodiment, a reversing pump is placed between the dispense cartridge and fluid source to continually or continuously pump fluid into and out of the dispense cartridge.

Abstract: Disclosed are a system and method for supplying chemical during a semiconductor device fabrication process. The system includes a tank to store the chemical, a dispensing unit to hold the chemical, a refill line connected between the tank and the dispensing unit to supply the chemical from the tank to the chemical liquid dispensing unit, and a dispensing line connected between the chemical dispensing unit and a semiconductor substrate to supply the chemical from the chemical dispensing unit to the semiconductor substrate.

Abstract: A rotary pump plural component applicator apparatus is provided for dispensing plural components, such as resins and adhesives or the like, with an activator for the resins or adhesives. A plural component applicator uses an electric motor gear box driving first and second rotary pumps. The use of an electric motor driving plural rotary pumps improves the plural component applicator performance in the application of the plural components.

Abstract: An ammonia purification system includes a hydrocarbon removal station that removes hydrocarbons from gaseous ammonia via adsorption, a moisture removal station that removes water from gaseous ammonia via adsorption, and a distillation station including a distillation column connected with a condenser to facilitate removal of impurities from ammonia and condensation of gaseous ammonia to form a purified liquid ammonia product. The system further includes a storage tank to receive purified ammonia, a remote station connected with the storage tank, and a vaporizer connected with the storage tank. The vaporizer is configured to receive and vaporize liquid ammonia from the storage tank and deliver gaseous ammonia back to the storage tank so as to facilitate pumping of the ammonia to the remote station based upon a vapor pressure established within the storage tank.

Abstract: The invention relates to a liquid dispenser, in particular to a dosing dispenser with a discharge tubule with an integral outlet duct for delivering a liquid via an outlet port and an integrated return duct which extends along the outlet duct, a discharge tubule kit system and a discharge tubule. The liquid dispenser contains a supplying device with a supplying or dosing cylinder, a supplying or dosing plunger which can be moved back and forth therein for supplying the liquid from a container to an outlet duct in order to dispense the liquid via an outlet port of the outlet duct, the said outlet duct being formed in an integral manner by a discharge tubule. According to the invention, the outlet port is formed for connection to the return duct by means of a connecting device, which extends integrally in the discharge tubule along the outlet duct.

Abstract: Methods, processes, and apparatuses for the large scale synthesis of carbon nanostructures are provided. Metal catalysts having small diameter and narrow distribution of particle sizes are prepared and continuously injected as aerosols into a reactor. The metal catalysts are supported on supports that are substantially free of carbon. The metal catalyst, in the form of a powder, is placed in an injector that is shaken vertically. The powder is aerosolized, and the powder entrailed in the gas is passed through a conduit that is bifurcated where one portion delivers the powder to the reactor while the other portion connects back to the ejector that is located in between the gas source and the top part of the container.

Abstract: A disposable tube set apparatus is provided for delivering a precise volume of a fluid to containers which comprise a reservoir for a fluid, an inlet conduit to the said reservoir, at least one first outlet conduits from the reservoir, a sight tube connected to each of the at least one outlet conduit, each of the sight outlet tubes having an interior wall tapered away from a central vertical axis of each of the sight outlet tubes, a return conduit connecting each of the sight outlet tubes to the reservoir, and a second outlet conduit connected to each of the sight tubes.

Abstract: A drink dispensing system for at least one dispenser valve. The system includes a carbonator, an ice storage bin having heat transfer coils therein, a two-position valve, a carbonated water circuit, a source of water and a pump circuit. The two-position control valve acts in a first position to charge the carbonated tank with the source of water through a pump in the pump circuit. In a second position, the valve directs circulating flow through a closed loop carbonated water circuit which employs coils before and after the dispenser valves. A bypass around the pump allows flow at all times to the dispenser valves from the carbonator without passing through the pump. A shunt divides the output of the pump such that circulation is at about 15 gallons per hour even with the pump running at 100 gallons per hour. The shunt is not coupled with the pump with the control valve in the charge position. The pump may be a two-speed pump with the higher speed employed when the control valve is in the charge position.

Abstract: An apparatus and method for mixing and injecting or applying a viscous material which is especially useful for mixing and applying a two part epoxy. The apparatus in its preferred form utilizes two uniformly heated holding tanks with auger feeds which each feed two synchronized variable ratio pumps having spring biased check valves which ensure positive closure of each valve. The apparatus further comprises a unique dispensing and mixing head which is fed from the synchronized pumps and serves to uniformly mix the viscous materials and dispense the aforesaid as a blend.

Abstract: The present invention relates to apparatus and method for re-circulating high viscosity liquids. The apparatus comprises a recirculating probe coupled to a fluid storage and dispensing vessel by a connector, and the recirculating probe comprises: (a) a dip tube defining an output flow path; (b) an output port; (c) a recirculating port; and (d) a return flow path. The output flow path and the return flow path preferably have substantially equal cross-sectional areas, which reduce or eliminate the unbalance between the discharge pressure in the output line and that in the re-circulation line, and prevent premature wearing-out of the dispensing/recirculating pump.

Abstract: A spray urethane gun assembly having a main body with a bore and a mixing chamber. An elongated spool is longitudinally, slidably mounted in the main body bore and movable between an extended position and a retracted position by an actuator. A first and a second inlet port are formed in the main body and a first and second outlet port are also formed in the main body. A first axially extending fluid passageway is formed in the spool and this first fluid passageway fluidly connects the first inlet port with the first outlet port when the spool is in one of the retracted or extended position, and fluidly connects the first inlet port with the mixing chamber when the spool is in the other of the retracted or extended position.

Abstract: An apparatus and method for mixing and dispensing gasoline and oil from a tank in which a flow of gasoline and oil is diverted from a dispenser pump outlet back into the tank to create a mixing of the gasoline and oil to dispensing the mixed gasoline and oil by operation of a dispensing nozzle also connected to the pump outlet.

Abstract: A small-scale portable recyclable fluid flushing method used for flushing irritants or inflammatory agents from the skin or eyes, or for flushing infectious debris from wounds. The invention is either made reusable or disposable, and typically comprises: a. a single or plurally chambered container with at least one flushing fluid chamber filled with an uncontaminated flushing fluid appropriate for the intended flushing procedure; b. a first outflow fluid conduit, e.g., a channel or tube, which transports uncontaminated fluid from the container flushing fluid chamber to a pump or impeller housing; c. a manual or electrically operated pump or impeller for transporting uncontaminated fluid through to a second outflow fluid conduit to a dispersal outlet or nozzle; d. a fluid runoff collector surrounding the dispersal outlet, or a catch basin situated below the dispersal outlet, either of which acts as a sump to capture the contaminated runoff fluid from the flushing procedure; e. a first drain fluid conduit; f.

Abstract: Apparatus for dispensing a liquid includes a manifold having a high pressure passageway adapted to be coupled to a source of the liquid and to deliver the liquid at an elevated pressure to a dispenser. The manifold further includes a low pressure passageway for exhausting pressurized liquid from the high pressure passageway. A pressure relief valve is coupled between the high pressure passageway and the low pressure passageway. The pressure relief valve has a valve member mounted for movement relative to a valve seat. One side of the valve seat defines a high pressure side in communication with the high pressure passageway and another side of the valve seat defines a low pressure side in communication with the low pressure passageway. A dynamic seal engages the valve member on the low pressure side and prevents leakage of the liquid from the low pressure side.

Abstract: The invention relates to a dispensing device and a method for dispensing liquids, preferably reagents, in an essentially automated and finely dosed manner. The dispensing device comprises a first duct that is connected to a storage element for storing the liquid to be dispensed. In addition, a conveying element for conveying the liquid through the fist duct is provided, whereby the liquid has to be dispensed. Liquid is transported from the storage element and is conveyed into the first duct by the conveying element. Moreover, the dispensing device is provided with a closing device that is arranged downstream in the conveying direction of the liquid in relation to the conveying element and serves for quickly closing and quickly opening the first duct. The aim of the invention is to regulate the pressure of the liquid in the region between the conveying element and the closing device. A device for regulating the pressure of the liquid in this region is provided.

Abstract: Disclosed is a device for dispensing fluids such as hand soaps. The device provides a recovery bin that captures run off or dripping fluid thus reducing or substantially eliminating waste of the fluid.

Abstract: A gas reclamation system for use in a beverage dispensing system. The system includes a valve for releasable connection to a used beverage container containing a pressurized gas, the valve allowing release of gas from the container. A filter for removal of particulate matter from the gas and a sterilizer for removal of bacteria from the gas are also provided, together with a compressor to re-pressurize the filtered and sterilized gas for supply to the beverage dispensing system. The system may be used for carbon dioxide recovery from beverage containers, reducing the consumption of carbon dioxide from beverage dispensing systems.

Abstract: A solid detergent dispenser for use with a dishwashing machine includes a chamber and a lid. The chamber is configured and arranged to receive a solid detergent having a particular composition. A water inlet receives water from a water source, and the water flows through a tunnel into the bottom of the chamber. The chamber is flooded with water from the bottom to ensure relatively constant erosion of the solid detergent, which ensures that a relatively constant concentration of the solid detergent is used in the dishwashing machine. A water outlet allows water to flow out of the chamber into the dishwashing machine. The water must flow into the chamber faster than it flows out of the chamber to ensure that the appropriate amount of dissolution of the solid detergent occurs. The only valve used in the preferred embodiment is a valve to control the amount of water flowing into the water inlet.

Abstract: A dispensing apparatus includes recirculating systems though which the dispersants are recirculated to prevent settling of solid components, such as pigments that may be present in the dispersants. The apparatus includes dispensers located on a movable table positioned inside a frame assembly of the apparatus. The table is positioned to dispense a selected dispersant into a container placed atop a weighing scale through the dispenser selected in accordance with a recipe. The weight of the selected dispersant is monitored by the weighing scale and once a desired amount of the selected dispersant is dispensed, a signal is received by the apparatus from the weighing scale to switch off the dispensing of the dispersant. The table is then moved to deliver the next dispersant, required in the recipe. The process is continued until all the desired dispersants are dispensed in the container to form the composition, such as an automotive paint.

Abstract: A piston device for dispensing controlled amounts of pasty substances, such as ice creams, that is connectable to the freezing chamber of an ice cream making machine.

Abstract: A piston device for dispensing controlled amounts of pasty substances, such as ice creams, that is connectable to the freezing chamber of an ice cream making machine.

Abstract: A fuel conduction system is provided for conducting fuel between a fuel source and a fuel consuming device which are either integrated as a single unit or apart as separate units. The system generally comprises concentric supply and return tubes for connection between the fuel source and the pump of a consuming device. A valve is positioned in series with the supply line which prevents siphoning of the contents of the supply line if it is damaged. Anti-siphoning and flashback arrest measures are also provided on the return line. In one embodiment, the fuel conduction system may be used on a portable fuel storage devices for refueling various consuming devices. In another embodiment, the fuel conduction system may be used on a fuel consuming device, between the pump and fuel storage container thereon, so that the fuel storage container may be selectively separated from the device in a safe manner.

Abstract: A metered output hot melt adhesive dispensing system comprises a plurality of hot melt adhesive dispensing valve assemblies, and a multiple outlet metering gear pump for supplying hot melt adhesive material to the plurality of valve assemblies. Return ports of the valve assemblies are fluidically connected to the intake side of the multiple outlet metering gear pump through a plurality of return conduits and a common return line. A single output return metering gear pump is disposed within the common return line and has operatively associated therewith a recirculation bypass loop within which a spring-biased one-way check valve is disposed. The system relieves excess pressure buildup within the valve assemblies so as to substantially prevent the occurrence of bursting and stringing phenomena attendant cyclically intermittent OPENED and CLOSED states of the plurality of valve assemblies.

Abstract: A hot melt adhesive material flow control system comprises an input manifold for receiving a supply of adhesive material, a plurality of flow control valves from which the adhesive material is discharged, an output manifold for heating the adhesive material and conducting the hot melt adhesive material to the flow control valves, a pair of multiple outlet pumps for supplying the adhesive material to the flow control valves, and a recirculation pump for recirculating adhesive material back from the flow control valves to the pair of multiple outlet pumps. A distribution plate and a recirculation plate are interposed between the input and output manifolds and have separate and independent fluid circuits or flow paths defined upon opposite surfaces thereof. In this manner, the number of plates required to define the flow paths is significantly reduced.

Abstract: The present invention relates to apparatus and method for re-circulating high viscosity liquids. The apparatus comprises a recirculating probe coupled to a fluid storage and dispensing vessel by a connector, and the recirculating probe comprises: (a) a dip tube defining an output flow path; (b) an output port; (c) a recirculating port; and (d) a return flow path. The output flow path and the return flow path preferably have substantially equal cross-sectional areas, which reduce or eliminate the unbalance between the discharge pressure in the output line and that in the re-circulation line, and prevent premature wearing-out of the dispensing/recirculating pump.

Abstract: A metered output hot melt adhesive dispensing system comprises a plurality of hot melt adhesive dispensing valve assemblies, and a multiple outlet metering gear pump for supplying hot melt adhesive material to the plurality of valve assemblies. Return ports of the valve assemblies are fluidically connected to the intake side of the multiple outlet metering gear pump through a plurality of return conduits and a common return line. A single output return metering gear pump is disposed within the common return line and has operatively associated therewith a recirculation bypass loop within which a spring-biased one-way check valve is disposed. The system relieves excess pressure buildup within the valve assemblies so as to substantially prevent the occurrence of bursting and stringing phenomena attendant cyclically intermittent OPENED and CLOSED states of the plurality of valve assemblies.

Abstract: A liquid spraying system having a spray head and a recirculating liquid supply system for directing pressurized supply liquid to the spray head with a portion of the liquid being directed from the spray head as a discharging spray and a portion of the supply liquid exiting the spray head as a return liquid. The liquid supply system includes two separate selectively pressurizable liquid containable tanks each having a respective fluid conduit coupled to the spray head. The liquid supply system has (1) a first cycle of operation in which the first tank is pressurized and the second tank is depressurized so that pressurized liquid is supplied from the first tank to the spray head and return liquid is directed to the second tank, and (2) a second cycle of operation in which the second tank is pressurized and the first tank depressurized so that liquid is supplied to the spray head from the second tank and return liquid is directed to the first tank.

Abstract: A directional control valve having three positions controls the direction of flow through an asphalt distributor. The directional control valve is interposed between a pump and a feed line assembly to a spray bar. The directional control valve has a first position in which flow is recirculated through the pump, a second position in which flow is delivered to the spray bar and a third position providing for handspray and transfer operations. A pressure relief valve is provided for controlling return flow of asphalt from the spray bar to the tank. The pressure relief valve is open in spray bar circulation mode and is closed during a spraying mode. According to the preferred embodiment the directional valve and pressure relief valve are contained within a modular control valve assembly. The directional control valve eliminates the need to reverse the flow in one of the individual feed lines and feed line assembly connecting the modular control valve assembly to the spray bar.