Abstract: The present disclosure relates to electronically-controlled air assemblies having an inflation, a deflation, and a closed state for use with inflatable products, such as air mattresses. Specifically, the present disclosure relates to air assemblies where the configuration of the air assembly can be changed by a user operating a directional control valve to inflate, deflate, or close an inflatable product. The air assembly may also maintain a predetermined air pressure value within the inflatable product.

Abstract: A pump includes a first gear plate and a first pair of counter rotating gears positioned on a first side of the gear plate. The pair of counter rotating gears draws fluid from an inlet and transfers the fluid into an outlet of a common manifold. The gear plate has a cutout to increase the flow of fluid into the common manifold.

Abstract: A pump assembly comprising a casing having a first pump chamber defining a first flow path and a second pump chamber or more defining a second flow path. A first pump stage includes a first shaft mounted to the casing for rotation about a rotation axis, a first pair of intermeshing gears disposed in the first flow path of the first pump chamber, the first pair of intermeshing gears interfacing each other in operative engagement, one intermeshing gear of the first pump stage mounted on the first shaft. A second pump stage includes a second shaft mounted to the casing for rotation about a rotation axis different than the rotation axis of the first shaft, a second pair of intermeshing gears disposed in the second flow path of the at least second pump chamber, the second pair of intermeshing gears interfacing each other in operative engagement, one intermeshing gear of the second pump stage mounted on the second shaft. A transmission drivingly engages the first shaft to the second shaft.

Abstract: A hydraulic pump (6) comprising: a housing (20) having first and second inlets (100a, 100b) and first and second outlets (102a, 102b); a crankshaft (4) extending within the housing (20) and having axially offset first and second cams (62, 64); first and second groups (30, 32) of piston cylinder assemblies provided in the housing (20), each of the said groups (30, 32) having a plurality of piston cylinder assemblies having a working chamber of cyclically varying volume and being in driving relationship with the crankshaft (4); one or more electronically controllable valves (40) associated with the first and second groups (30, 32); and a controller (70) configured to actively control the opening and/or closing of the said electronically controllable valves (40) on each cycle of working chamber volume to thereby control the net displacement of fluid by the first and second groups (30, 32), wherein at least the first group (30) comprises a first piston cylinder assembly in driving relationship with the first cam

Abstract: A valve body is provided with a discharge relief portion. A relief valve outlet is formed in an end face thereof on a central axis of the valve body. Discharge valve inlets are point-symmetrically formed with respect to the central axis. A discharge valve outlet is formed in another end face thereof and relief valve inlets are point-symmetrically formed with respect to the central axis. A discharge valve outlet and the discharge valve inlets communicate with each other. A flow of fuel from a pressurization chamber to a fuel discharge port is restricted by a discharge valve member capable of closing the discharge valve outlet. The relief valve outlet and the relief valve inlets communicate with each other. A flow of fuel from the fuel discharge port to the pressurization chamber is restricted by a relief valve member capable of closing the relief valve outlet.

Abstract: The present invention relates to a double hydraulic machine (100) comprising two elementary machines (M1, M2) each having two orifices, the double hydraulic machine (100) comprising a distribution valve (7) suitable for, in a first configuration (C1), feeding both elementary machines (M1, M2) in parallel, and in a second configuration (C2), producing a short circuit of one of the elementary machines (M2). The invention also relates to a system for driving a vehicle comprising such a hydraulic machine (100) for driving the vehicle into motion.

Abstract: A planter system includes a planter having an unloading valve and a controller. The unloading valve is fluidly coupled between an inlet and an outlet of a pump. The unloading valve is configured to receive a fluid at a supply pressure, to supply a first portion of the fluid from the inlet to a hydraulic planter system at an unloading pressure less than the supply pressure, and to recirculate a remainder of the fluid to the pump via the outlet. The controller is communicatively coupled to the unloading valve and to the pump. The controller is configured to control the pressure of the fluid supplied to the inlet and to control the unloading pressure of the first portion supplied to the hydraulic planter system.

Abstract: A hydraulic system, including fluid flow generated by a primary pump and a secondary pump, utilizes a regulator control assembly to control fluid flow from each of the primary and secondary pumps such that a desired fluid flow and pressure is maintained at the outlet for varying actuator demands. The regulator control assembly controls the transition from using only the primary pump, to using both the primary and secondary pumps to provide a desired fluid flow and pressure through the outlet to the actuator.

Abstract: A method is provided for regulating a charge air pressure of an engine having an exhaust gas supercharger, a fresh gas supply device, an air system having an air treatment system and a compressor chargeable by the supercharger, and an engine controller. The method detects an engine torque requirement; determines a current charge air pressure and a current pressure of the air system; compares the current charge air pressure to a target charge air pressure corresponding to the torque requirement, compares the current air system pressure to a target operating air system pressure, and regulates the charge air pressure by suppressing supply of compressed air from the supercharger to the compressor when the current charge air pressure is less than the corresponding target charge air pressure and the current pressure of the air system is greater than or equal to the target operating pressure of the air system.

Abstract: A control method and apparatus for critical rotational speed avoidance in a compressor-expander set in a gas refrigeration system. By varying an opening of an antisurge or recycle valve, a shaft power used by the compressor in the compressor-expander set may be varied, thereby varying the rotational speed of the compressor-expander set to move it away from its critical speed zone. Additionally, a feedforward signal may be provided by a compressor-expander set control system to cause an antisurge valve for a recycle compressor to open upon a trip or shutdown of one compressor-expander set.

Abstract: A dual-pump fluid distribution system that includes a first pump having an inlet and an outlet, and configured to supply a first flow of fluid, and a second pump having an inlet and an outlet, and configured to supply a second flow of fluid. In an embodiment, a bypass flow valve with a four-way hydraulic bridge is configured to initiate the switch between single-pump mode and dual-pump mode based on fluid flow demand. The bypass flow valve is configured such that the position of the bypass flow valve member relative to the four-way hydraulic bridge operates a pump selector valve. In an embodiment, the pump selector valve has a valve member, a biasing element, and a pressure switching port, and is configured such that the position of the valve member determines whether the second flow of fluid is combined with the first flow of fluid.

Abstract: A fuel flow system for a gas turbine engine includes a first pump, a second pump, a bypass loop, an integrating bypass valve and a pilot valve. The first pump connects to an actuator and a metering valve. The second pump connects to the metering valve and is arranged in parallel with the first pump. The bypass loop recycles fuel flow from the first pump and the second pump to inlets of the first pump and second pump integrating bypass valve includes first and second windows. The first window regulates fuel from the first pump through the bypass loop and the second window that regulates fuel from the second pump through the bypass loop. The pilot valve controls the size of the first and second windows.

Abstract: A control method and apparatus for critical rotational speed avoidance in a compressor-expander set in a gas refrigeration system. By varying an opening of an antisurge or recycle valve, a shaft power used by the compressor in the compressor-expander set may be varied, thereby varying the rotational speed of the compressor-expander set to move it away from its critical speed zone. Additionally, a feedforward signal may be provided by a compressor-expander set control system to cause an antisurge valve for a recycle compressor to open upon a trip or shutdown of one compressor-expander set.

Abstract: A multi-pump assembly and method of use including a housing and at least two pumps contained within the housing is described, wherein each pump has a performance level. In an embodiment, the performance level of each pump is the same. In another embodiment, the performance level of each pump is different. The assembly may also include a common electrical inlet, a common fuel inlet connection, a common fuel outlet connection, a pressure regulator, a final filter, an outlet check valve connected to each pump, a plurality of over pressure relief valves connected to each pump and an over pressure relief passage formed around the pumps in the housing, an electronic controller capable of operating each pump independently, a fuel filter and a pressure regulator in the housing to form a returnless fuel supply, and/or a final filter. The assembly may be used in a multiple carburetor or fuel injection applications.

Abstract: A variable displacement rotary pump includes a main pump unit, an auxiliary pump unit, a discharge passage, a bypass passage, a suction passage, a check valve and a control valve. The suction passage is in communication with the discharge passage through the bypass passage and a second discharge port. The check valve is disposed in the discharge passage for preventing fluid in a first discharge port of the main pump unit from flowing into the bypass passage. The control valve is operable for opening and closing the bypass passage. When the control valve opens the bypass passage and the check valve closes the discharge passage, flow rate of the fluid discharged from the discharge passage is reduced. A throttle passage is provided in the bypass passage or the control valve for regulating flow of the fluid in early phase of operation of the control valve to open the bypass passage.

Abstract: A pump apparatus for transporting at least one fluid, comprising a shaft, wherein the shaft has a longitudinal axis; a motor, wherein the motor is adapted to rotate the shaft about the longitudinal axis; and, a plurality of gerotors, wherein the gerotors are attached to the shaft along the longitudinal axis and wherein the shaft rotation actuates the plurality of gerotors rotation, causing pumping of the at least one fluid.

Abstract: A multiple stage pump having valves downstream from each respective pump in a same line thereof. The respective lines then merge into a common line. The multiple stage pump prevents pressure variations and shot to shot fuel variations.

Abstract: A hydraulic control circuit for a radial piston engine with two speeds. The changeover between the speeds takes place through the alteration of the absorption volume, the delivery side being connected to the discharge side with a bypass connection by a valve arrangement for a selected number of engine pistons. The control circuit provides a space-saving way of ensuring that the changeover between speeds occurs smoothly and in such a manner to preserve the individual components as far as possible. To this end, at least one intermediate switching position, in which the delivery side is throttled to the discharge side, i.e. connected by a diaphragm-type arrangement, is provided in front of valve arrangement between the two end switching positions. The valve arrangement is preferably driven such that a valve body can be moved through the intermediate switching position at a controlled speed.

Abstract: A multiple stage pump having valves downstream from each respective pump in a same line thereof. The respective lines then merge into a common line. The multiple stage pump prevents pressure variations. The multiple stage pump includes a first pump in a first stage and a second pump in a second stage. At least one valve is downstream from one of the first pump and the second pump in at least one of the first stage and the second stage. A common branch line connects the first stage and the second stage to a common hydraulic system.

Abstract: A multiple stage pump having valves upstream from each respective pump in a same line thereof. The respective lines then merge into a common line. The multiple stage pump prevents pressure variations. The multiple stage pump includes a first pump in a first stage and a second pump in a second stage. At least one valve is upstream from one of the first pump and the second pump in at least one of the first stage and the second stage. A common branch line connects the first stage and the second stage to a common hydraulic system.

Abstract: Pumps and methods for inflating objects with atmospheric air employ a fan pump to quickly fill the object with air and then shunt away the air from the fan pump, and use a diaphragm pump to increase the pressure until the inflatable object attains the firmness or pressure required for the object to be useable.

Abstract: A tandem pump apparatus is featured having a main suction passage connected to a fluid source. The main suction passage branches into first and second suction passages which, in turn, feed into first and second pumps. Each pump discharges a portion of the fluid to a return passage that is fluidly connected to the suction port of each respective pump. In each return passage, a return control valve is disposed to control the amount of fluid returned to the suction port. The tandem pump featured in this invention exhibits increased efficiency and decreased noise.

Abstract: The present invention relates to an oil supply system with at least one pressure and/or volume dependent controllable pump (1) and an oil tank (5) or the like from which the pump draws oil and delivers it with controlled output pressure or output volume to a system (8) to be supplied.

Abstract: A gear pump having three gears, including; a pump case consisting of a pump body and a cover for covering most of the body; three gears which are supported by a rotating shaft on the pump case and engaged with each other in series; first and second gear pumps each composed of one central drive gear and one of the driven gears on both sides of the drive gear; a non-return valve and a flow regulation valve which are opened at a predetermined pressure; an inlet port which is opened at one end of the pump case and connected through a feed path to the suction side of the two gear pumps; an outlet port formed on the discharge side of the first gear pump in the pump case; a regulation path passing from the discharge side of the second gear pump through the non-return valve to the outlet port; and a flow regulation path passing from the regulation path through the flow regulation valve to an oil pan.

Abstract: An improved dual-stage pump system is provided for the accurate pumping and filtering of viscous fluids. Two hydraulically activated pumps are provided in series with a filter and reservoir disposed in-line between the two pumps. The reservoir acts as a source bottle for the second pump and allows the first pump to pump the viscous fluid through the filter at a rate independent of the dispensing rate of the second pump. By operating the first pump at a rate independent of the second pump, back pressure at the filter is avoided. Each hydraulically activated diaphragm pump is equipped with an improved diaphragm that is pre-formed to the geometries of the process fluid cavity thereby eliminating any inaccuracies in the operation of the pumps due to expansion of retraction of the diaphragm during pump operation.

Abstract: An improved air pump comprises at least two parallel cylinder chambers communicating via two channels with a receiving space in which an air valve connecting device is disposed for injecting high pressure air into an object to be inflated. A pressure releasing member is disposed between the channels and the receiving space for regulating the pace of pumping the air into the object. When the air pressure inside the object is low, the pumping of the air into the object is done rapidly. When the air pressure inside the object has reached a high level, the pumping of the air into the object is done by only one cylinder chamber of the air pump.

Abstract: A modular fuel sender in a fuel tank of a motor vehicle includes a reservoir, a fuel pump in the reservoir, a low pressure conduit conducting hot return fuel back to the reservoir, a secondary pump in the reservoir for pumping new fuel from the tank into the reservoir, and a control which effects a recirculation mode of secondary pump operation when the new fuel level in the fuel tank is above a predetermined low level and a scavenge mode of secondary pump operation when the new fuel level in the reservoir is below the predetermined low level. In the recirculation mode, the secondary pump recirculates reservoir fuel to avoid overflowing hot fuel into the fuel tank. In the scavenge mode, the secondary pump continuously maintains a partial vacuum in a screen in the fuel tank regardless of the fuel level in the reservoir to maximize new fuel scavenged from the fuel tank before fuel starvation occurs.

Abstract: The first of two serially arranged electromagnetically operated spool type drain control valves is conditioned to select the drain passage of smaller the pump before the second valve is moved from its closed or communication cut-off position, to its open position wherein hydraulic fluid can be drained therethrough, whereby the spool of the second valve is exposed to a relatively small flow generated force which acts thereon and which tends to move the valve spool toward to its closed position. In another embodiment the hydraulic fluid temperature is monitored and used to modify the control schedule via which the switching of the drain control valves is determined. A further embodiment monitors a parameter which is indicative of the prime mover rotational speed and inhibits the closure of the second of the two valves when the rotational speed is above a predetermined limit.

Abstract: A switch-over valve 6 is provided in a pressure circuit 31 between a hydraulic pump 2a and a clutch 7, and a pressure limiting valve 5 is provided between a reflux circuit 9 for the valve 6 and the pressure circuit 31. The clutch actuating hydraulic circuit includes another hydraulic pump 2b, and a switch-over valve 8 for switching over a discharged fluid of the hydraulic pump 2b. A downstream side of the switch-over valve 8 is connected to the pressure circuit 31 and to the reflux circuit 9. Consequently, when the clutch is engaged or disengaged, the discharged fluid of the hydraulic pump 2b is combined with the discharged fluid of the hydraulic pump 2a so as to increase the flow rate to the clutch 7.

Abstract: A hydraulic system for powering a vehicle for human transporation. The output of a hydraulic pump is connected to at least one hydraulic motor by a hydraulic circuit, the motor(s) being mechanically connected to drive the vehicle. The hydraulic circuit establishes the direction of fluid flow through the motor(s). The pressure drop across at least a portion of the hydraulic circuit is monitored and the flow of fluid to the circuit is regulated accordingly.

Abstract: A fuel pump having a first pumping mechanism for pumping a fuel in a main tank to a subtank and having a second pumping mechanism for pumping the fuel in the subtank to an outside of the main tank. The fuel pump includes a rotatable impeller having a plurality of outer peripheral vanes, and a wall member surrounding the vanes so as to define a fuel flow passage. The wall member has two partition walls for partitioning the fuel flow passage into a first pumping passage and a second pumping passage, a first suction hole for communicating an upstream end of the first pumping passage to the main tank, a first discharge hole for communicating a downstream end of the first pumping passage to the subtank, a second suction hole for communicating an upstream end of the second pumping passage to the subtank, and a second discharge hole for communicating a downstream end of the second pumping passage out of the main tank.

Abstract: A fuel pumping apparatus, particularly useful for gas turbine engines, includes a dual element positive displacement fuel pump having a centrifugal type boost stage and, downstream, at least two parallel gear type elements. A controllable means for unlocking at least one of the elements includes a bypass line which provides a flow path to the inlet of the fuel pump from the pressurizing chamber of the gear elements which is used to urge end bearings of the gear elements into contact with the revolving gears thereby enabling the gears to pump fluid. Disposed in the bypass line is slide valve to open up the bypass line and unload and render the unloadable gear element inoperative. Control is provided by a Full Authority Digital Electronic Control and its associated Hydromechanical Unit which uses the fuel as a hydraulic fluid to actuate the slide valve.

Abstract: A variable discharge pump comprises a plurality of pumping units, each pumping unit including an outlet port discharging a particular volumetric discharge of working fluid, a plurality of outlet passages respectively communicating the outlet ports of each of the pumping units. Each of the outlet passages includes a supply passage provided for supplying the working fluid to a driven apparatus and a reflux passage provided for returning the working fluid to a working fluid reservoir, both being branched from the outlet passage.

Abstract: A supply passage communicates with the inlet of a first centrifugal pump. A second, smaller centrifugal pump has its outlet connected to a delivery conduit. A valve arrangement is selectively operable to connect the inlet of the second pump either to the output of the first pump or directly to the supply passage, both the inlet and outlet of the first pump being shut off in the latter condition.

Abstract: A rotary compressor includes first and second compressor sections, and a motor for driving the compressor sections. The first and second compressor sections have first and second cylinders, respectively, and each cylinders has a suction port. First and second suction pipes are connected to the suction ports, and first and second change over valves are provided at the first and second pipes, respectively. The first cylinder has a release port for releasing a port of the gas being compressed in the first cylinder. A release pipe provided with a third changed over valve is connected to the release port. The operaations of the first to third valves are controlled by a control circuit so that the capacity of the compressor varies in the plurality of steps in accordance with the loads applied thereto.

Abstract: A variable displacement radial piston pump includes a plurality of pump sections which are grouped into two. A first group of pump sections are communicable through a first discharge passage with a third discharge passage. A second group of pump sections are communicable through a second discharge passage with the third discharge passage. A control valve is provided for selectively supplying discharge from said first and second groups of pump sections to the third discharge passage and thereby stepwisely varying the discharge through the third discharge passage.

Abstract: In a compressor having a plurality of banks of cylinders, smaller steps of unloading are achieved by unloading a single cylinder in a bank. When only one cylinder is to be unloaded, gas bypass is used in order to maintain a closer balance of forces in the bank. When the entire bank is unloaded, it is preferably done via the suction cutoff method.

Abstract: A fluid pump system whose output can be varied by converting it from maximum output to a lesser output and in between by dumping or varying one of its pumping elements or pistons to the inlet side of the pump. More specifically, a pump is provided with two opposed pistons, both of which are connected to inlet and outlet for maximum capacity. The piston chamber of one piston is equipped with a converter line for leading that chamber back to the inlet, whereby only the remaining piston furnishes the pump discharge. Variations in the adjustable mode of the valve is reflected in the action of the pump relief valve to cause increased effectiveness of a jetter line supplied by the pump output.

Abstract: A fuel injection pump for internal combustion engines having in-line pumping elements, having pump pistons on which control slides are axially displaceable, in particular for adjusting the injection onset; in a relatively greatly displaced position, these control slides being arranged to interrupt the injection. The control slides are moved by first and second governor rods, each part of which carries one group of driver members of the control slides, and both governor rods are rotatable relative to one another. As a result, it is possible for normal operation to be controlled by the one governor rod, while at the same time an appropriate number of engine cylinders is shut off by the other governor rod, in that the associated control slides are displaced into respective corresponding positions.

Abstract: A plant for de-icing especially surfaces of aeroplanes, comprising the use of at least two sources (10, 12) of liquid media that are different from each other and capable of being sprayed separately or as a mixture, comprising a number of positive liquid pumps (16, 22) corresponding to the number of media, which pumps all have the same capacity or a predetermined interrelated capacity ratio and terminate in a common spray pipe (24). The connection of the liquid pumps to the sources includes at least one of the sources to at least one of the liquid pumps. In a hydraulic system comprising hydraulic motors (56, 52) for driving the liquid pumps (16, 22) at least two of motors are connected to a common hydraulic pressure pump (32) controlled by way of pressure compensation (33) to work with at least two pressure stages subject to a ratio corresponding to that of the capacity of at least one liquid pump to the total capacity of both liquid pumps.

Abstract: A lubricant distribution system for refrigeration units having a plurality of parallel compressors which system maintains the proper level of lubricant in the compressors during operation. The system comprises compressor suction inlet lines which connect each of the compressors of the system with a common suction header located at an elevation below the suction inlets on the compressors. The common suction header is connected to the evaporator outlet by a conduit which extends from the evaporator to the common suction header. The compressors suction inlet lines are sized to provide a suction gas mass velocity therethrough which is sufficient to carry lubricant into the compressors as an entrained liquid even when the compressors are operating at partial capacity.

Abstract: A pump is provided for circulating drilling fluid and the like into a well during a well drilling process. The pump comprises a pair of double-ended piston assemblies hydraulically reciprocated in opposite directions by a common hydraulic drive arrangement, wherein each piston assembly has a relatively large piston at one end and a relatively small piston at an opposite end. The various pistons reciprocate within appropriately sized cylinders each having a working end with a one-way intake valve through which drilling fluid is drawn from a supply tank and a one-way discharge valve through which drilling fluid is discharged to the well.

Abstract: A hot gas centrifugal fan is constructed with a scroll part comprising spaced-apart walls 16 and 18 to define a hot gas passage 22 therebetween to which hot gas is conveyed when the fan is in a non-operating condition to hold the fan temperature sufficiently high to avoid unacceptable vibration brought on by thermal distortion of the fan wheel upon a re-start of the fan.

Abstract: The control valving for a dual pump hydraulic system has two regulator valves which control the distribution of pressurized fluid, on a priority basis, to a high pressure system, a low pressure system and a lube system. One regulator valve controls flow from both pumps to the high and low pressure systems. The other regulator valve controls flow from one pump to the lube system and bypasses excess flow from the other pump to the system reservoir. The first regulator valve satisfies the high pressure system requirements before any fluid is directed to the low pressure system. The other regulator valve receives fluid downstream of the first regulator valve and satisfies the low pressure system before any fluid is directed to the lube system or to the fluid return passage to the reservoir.

Abstract: There is disclosed a multistage gear pump and control valve arrangement comprising two hydraulic gear pump sets each having a suction port connected to a common sump and a discharge port for delivering hydraulic fluid to a circuit line. Only one of the discharge ports is continuously open to the circuit line while a check valve operates to connect the other of the discharge ports to the circuit line and prevent reverse flow. A regulator valve regulates the pump discharge to the circuit line by diverting fluid therefrom in response to circuit line pressure below a predetermined setting while both the discharge ports are delivering fluid thereto and by being responsive to circuit line pressures thereabove to connect the other discharge port to the sump to thereby relieve the associated gear pump set of hydraulic work while again regulating the pump discharge to the circuit line by diverting fluid therefrom but with only the one discharge port delivering fluid thereto.

Abstract: A discharge flow control rate valve for a multiple cylinder type reciprocating pump has a flow rate control valve associated with two cylinders of the pump. The flow control valve has a bypass passage connecting the suction side of the pump with a stepped cylinder chamber provided in the body member of the control valve. A needle valve fitted with a separate valving element is reciprocably disposed in the stepped cylinder chamber and operates to return a part of the fluid in the first cylinder or in the first and second cylinders to the suction side of the pump as a function of the intrusion distance of the valve into the cylinder chamber so as to modify the overall discharge flow rate of the pump.

Abstract: A parallel operation compressor type refrigerating apparatus is disclosed which has first and second compressors connected in parallel with each other by a pipe, each having the inside of its crankcase separated into a motor chamber and a compressing element chamber by a partition provided with a pressure equalizing opening and a lubricant equalizing nonreturn valve allowing lubricant passage only from the motor chamber side to the compressing element chamber side, and which comprises a means provided at the end of a suction pipe of a refrigeration cycle system to separate the refrigerant gas circulating within the suction pipe into a lubricant and a gas, a first branch pipe to supply a portion of said gas to the first compressor, a second branch pipe to supply the rest of the gas and the lubricant to the second compressor, a pressure and lubricant equalizing pipe connecting together the lubricant sinks of the two compressors, and a nonreturn valve provided in the pressure and lubricant equalizing pipe to blo

Abstract: An arrangement of water pumps comprising two electric motor operated pumps for each of a plurality of formations of nozzles whereby the water flow from the pairs of pumps to the various formations of nozzles may be selectively controlled by pluralities of electric switches located in a remote station. Electric circuitry associated with the switches controls the electric current flow to the various pump motors in a manner whereby the height of the water sprays emitted from the respective nozzles is selectively controlled along with providing a generally universal control over the activation of individual, various groups and formations of nozzles to produce a very wide range of different rhythmic visual effects.

Abstract: A fluid pumping system comprises a fluid pump having multiple fluid outlet flows coupled to relatively low and high pressure loads. A control valve system controls the pressure levels of the low and high pressure flows, and relieves excess fluid from the high pressure flow to the low pressure flow to augment the low pressure flow.

Abstract: A hot melt adhesive foam pump system having a first stage pump that meters molten hot melt adhesive into a second stage pump, which in turn mixes gas under pressure into the adhesive so that the gas is driven into solution with the adhesive at an adjustably controllable ratio. The pump is insensitive to changes in adhesive viscosity and pump speed, and provides uniformity of foam density and output flow rate when the adhesive is ejected from a dispenser connected to the pump.