Abstract: A submersible landfill pump system may include sensors to detect conditions inside the pump and/or well. In some embodiments, the sensors can be placed along an electrical wire within the well and provide sensor data to a user.

Abstract: A system and method are provided for improving hydrocarbon production from gaseous wells, and in particular improving hydrocarbon production using pumping systems employing artificial lifts. The pumping system of the well is controlled so as to cyclically decrease and increase gas pressure in the casing annulus, thus cyclically decreasing PBHP in response to the decrease in the casing annulus pressure and permitting the PBHP to increase in response to the increase in casing annulus pressure. Production of fluid from the reservoir is therefore increased during the cyclical decrease in casing annulus pressure, and production of fluid from the downhole pump is increased during the cyclical increase in casing annulus pressure. In addition, gas interference due to production of foam in the casing surrounding a downhole pump can be mitigated by forcing liquid from the foam during the period of increased casing annulus pressure.

Abstract: A system is provided to control fluid flow in a wastewater treatment system through wastewater level manipulation. The wastewater treatment system may include a wastewater treatment plant connected to a plurality of pump stations by a main. Each of the plurality of pump stations may include a wet well with a pump therein. The system may include a central server in communication with a sensor to sense a level of wastewater within the wet well. The pump may be automatically moved to an on position when the level of the wastewater in the wet well is at or above a first level and may be automatically moved to an off position when the level of the wastewater in the respective wet well is at or below a pump cutoff level. The central server may systematically manipulate the first level to selectively set the level of wastewater within the wet well.

Abstract: Reductions in energy consumption and maintenance requirements for operating a wastewater treatment plant are achieved by controlling the operation of pumps at pump stations along a force main in a systematic fashion. The operation of the pumps is controlled to manage the flow of wastewater along the force main to minimize energy consumption, to eliminate sediment, to manage peak pressures encountered by smaller pumps and to avoid septic conditions.

Abstract: A system that control levels of liquids in reservoirs may include a control component that causes a compressor to pump gas through a tube extending in a liquid in a reservoir to an air bell for a predetermined amount of time responsive to a pump pumping portions of a liquid from the reservoir. The control component may also cause the compressor to pump gas through the tube for a predetermined amount of time responsive to the control component determining that a predetermined amount of time has passed since the compressor was previously operated. The control component may also cause the compressor to pump gas through the tube for a predetermined amount of time, responsive to the control component determining that a pressure sensor component in fluid communication with the tube indicates a possible decrease in the liquid level to at least a predetermined level.

Abstract: Pumps for Steam Condensates and other Liquids, include receivers that may be connected firstly to the liquid source, and after filling are then pressurised to discharge the liquid to a transfer line, or to a vessel at a higher pressure than that of the source. The use of a small pilot valve to detect the liquid level, mounted externally to each receiver, and controlling the opening and closing of the pressurising and venting valves, enables an unusually low profile to be achieved.

Abstract: An automatic pressure-relieving apparatus for a suction pump comprises a pipework provided at the cap. A first rod positioned in the pipework has an upper sealing ring arranged around the top periphery thereof, whereby the first rod can detachably seal the upper opening of the pipework. Moreover, the first rod is coupled with a second rod, which is pierced through the lower opening of the pipework and extending into the oil reservoir of the cylinder. The second rod further has a sealing component arranged at the periphery thereof for moving. upward and detachably sealing the lower opening of the pipework. Also, a control device is fastened to the bottom of the second rod so that when the raising oil surface lifts a float of the control device, the float can in turn drive the first and second rods to move upward. Thereby, the upper and lower openings of the pipework are opened and closed respectively, and the pressure in the pump can be automatically released through the opened upper opening.

Abstract: The phase of this process is done by the functionality of the perforated lower stem, which due to the fact that its internal conduit is able to connect the lower bellow in an alternated way, first to the tubing and after, to the casing. This is possible due to the fact that it is assisted by: a) a window that communicates the casing with the tubing when the lower bellow is open, and b) sealing packing installed in the lower stem to isolate the casing pressure, in order that the lower bellow can register only the tubing pressure when it is in closing position.

Abstract: A method for using a controller to control a fluid pump by controlling the rate at which the pump fills with fluid and subsequently discharges fluid. The pump includes a chamber for collecting fluid from within a well bore in which the pump is disposed. A user inputs a pump cycle time and a pump cycle volume to the controller. The pump cycle time input is used to determine a cycling period for the pump. The pump cycle volume is used to allot a portion of the cycling period to the refilling of the pump with fluid and the remaining portion of the cycling period to the discharging of fluid from the pump. The controller controls the pump such that the pump is vented to atmosphere during the refill portion, allowing the pump to fill with fluid, and such that pressurized fluid, such as compressed gas, is injected into the pump during the discharge cycle, causing fluid collected within the pump to be discharged. In another mode of operation, a sensor is coupled to the controller.

Abstract: A method of supplying water from a well is provided. The method includes the following steps. First, a supply apparatus is provided that includes a container having first and second ends and a first chamber extending to a first opening in the second end. The supply apparatus also has a first fluid conduit with a first branch for use in transporting the water from the first chamber. Next, at least a portion of the second end of the container is submerged within the water in the well such that the first chamber contains a quantity of air. Then, at least a portion of the quantity of air from the first chamber is removed by an air compressor thereby drawing a vacuum within the first chamber. The vacuum in turn draws a quantity of water from the well into the first chamber through the first opening. Next, the removal of air from the first chamber is stopped when the water has obtained a first predetermined level within the first chamber. The first opening is then closed.

Abstract: A fluid pressurizing system and method according to which a fluid at a low pressure is compressed by fluid to increase its pressure to enable it to be discharged from the system and to an external delivery point.

Abstract: An intermittent gas lift well pumping system containing an accumulator, a gas line, a liquid discharge line, and a battery operated controller. By using one or more constrictions in the gas line and acoustical techniques, accurate liquid level is determined in the pumping system for optimum production. Bypasses are connected between the gas line and the liquid discharge line. Each contains a valve that opens at a preset absolute pressure in the gas line, an orifice, and a one-way valve. The bypasses are strategically placed to prevent overloading of the system. A liquid slug sensor on the upper end of the liquid discharge line and a rabbit in this line enables optimum production and gas conservation.

Abstract: A hydraulic control unit for a motor-vehicle braking system comprises a pump (32) delivering hydraulic fluid under pressure, said pump being capable of being controlled by an electronic control unit (ECU) and supplying the hydraulic fluid for at least one braking device (22) which is coupled to a wheel of the vehicle, and also a first reservoir (34) for pressureless hydraulic fluid, which is assigned to the pump (32) on the input side, and a second reservoir (36) for hydraulic fluid under pressure, which is assigned to the pump (32) on the output side. In order to design the control unit in such a way that it is not unshapely and problems [sic] as regards installation space arise in not uncritical manner, the pump (32), the first reservoir (34) and the second reservoir (36) are arranged in a common casing (60), integrated as an electrohydraulic modular unit.

Abstract: A pressure/vacuum generator is established by coupling the pressure port of a vacuum generator to an air pressure source while coupling a valve in fluid communication with the exhaust port of the vacuum generator. When the valve is in a normally open condition (i.e, the exhaust vented to atmosphere), the vacuum port of the pressure/vacuum generator generates a vacuum. When the valve is closed, thereby closing off the exhaust port, the vacuum port becomes a pressure port. Thus, this pressure/vacuum generator can be used in any number of fluid (liquid and gas) systems (e.g., fluid recovery system, fluid transfer system, etc.)that require both a pressure source and a vacuum source while using a minimum number of components.

Abstract: An automatic pneumatic pump system includes a fluid reservoir, at least one fluid tank connected to the reservoir through an inlet conduit and discharge fluid through an outlet conduit, a pressure sensing unit mounted on each fluid tank and containing a high pressure sensor and a low pressure sensor, a fluid level sensing unit mounted on each fluid tank and containing a high fluid level sensor and a low fluid level sensor, a microprocessor for controlling an operation of the pump system, an air supply conduit connected to the fluid tank to a compressor and the fluid level sensing unit, with the interior of the fluid level sensing unit being configured to communicate with the fluid tank, an air discharge conduit extends from the fluid tank, and an auxiliary air tank connected to both the air supply conduit and the air discharge conduit for automatically cleaning a fluid level sensing unit, improving pumping capacity, and recyclining discharged and compressed air.

Abstract: The present invention relates to a pulsatile flow system and method. The pulsatile flow system includes a reservoir, a pressure riser and a first fluid passage connected between the reservoir and the pressure riser. The system further includes a device adapted to expel fluid from the reservoir through the first fluid passage to the pressure riser. A second fluid passage is connected between the pressure riser and the reservoir, and is adapted to allow fluid to flow unidirectionally therethrough, from the pressure riser to the reservoir. The pulsatile flow system may be adapted to provide pulsatile fluid flow through a medical device, such as a ventricle assist device or mechanical heart valve, to replicate a heart's pumping action for testing the device.

Abstract: A device for disposal of liquid media such as coolant and lubricant fluids, containing production residues, such as chips from industrial processes in which these media are conveyed from at least one accumulation site through gutters and/or pipes to a recycling container. The media are conveyed from the recycling container through a pipe connected thereto close to the bottom to at least one collecting tank. The device is also intended to convey foamed media from the recycling container to the collecting tank at limited equipment cost. The recycling container is divided by a pressure-tight partition containing an operable valve into an upper supply chamber and a lower delivery chamber. A compressed air line with a switchable compressed air inlet valve and a vent line with a switchable vent valve are connected to the upper area of the delivery chamber.

Abstract: An automatic pneumatic pump preferably used with a waste water disposal system is disclosed. The pump forcibly introduces sludge-laden liquid into a tank (30) and in turn feeds the liquid to a filter unit (F) for filtering off the sludge. The pump has one air pressure pipe (61) and two air exhaust pipes (62, 63) provided to the upper portion of the tank (30). The air pipes (61 to 63) include their solenoid valves (71 to 73) which are selectively opened in accordance with the liquid level inside the tank (30). An air compressor (C) is mounted to the air pressure pipe (61) and selectively operated during a time when the liquid level inside the tank (30) reduces from a top level to a bottom level (S.sub.1). A vacuum pump (P.sub.2) is mounted to the second air exhaust pipe (63) and selectively operated during a time when the liquid level inside the tank (30) increases from the bottom level (S1) to the top level (S.sub.2).

Abstract: A liquid flow control apparatus (5) suitable for handling milk from a milking machine, comprising a first chamber (10) that comprises an inlet (11) for the milk, an outlet (12) for connecting to a vacuum pump, and an outlet (14) for the milk to flow by gravity to a second chamber (13). The first chamber (10) and the second chamber (13) are in communication with each other by means of the outlet (14) at the bottom of the first chamber (10). The second chamber (13) has a float valve (23) that closes off communication between the first chamber (10) and the second chamber (13) depending on the level of liquid in the second chamber (13). A conduit tube (18) for air communication is disposed between the first chamber (10) and the second chamber (13). A second float valve (17b) closes off communication via the conduit tube (18) between the two chambers. A third chamber (21) has two valves with one valve (26) opening to the atmosphere and a second valve (20) opening to the second chamber (13).

Abstract: An air-operated pump includes a pair of poppet valves affixed to a vertical valve shaft and arranged so that the upper valve is closed when the lower valve is open, and vice versa. When a connected displacer is immersed in tank fluid, its buoyancy in combination with a bias spring translates the valve shaft to operate the poppet valves. An upper poppet valve chamber is connected [1 ] via a restrictance to an auxiliary air supply, and also [2] to an air operator that triggers a three-way pneumatic valve, an inlet port of which controls a main air supply while a second port is vented to atmosphere. A third port transmits an air supply to the tank through the intermediation of a quick exhaust valve, which rapidly vents the tank at the end of each pump cycle and also serves to isolate the three-way valve from any tank-fluid contamination.

Abstract: There is provided a dual pump floating layer recovery apparatus for pumping a floating layer of contaminant out of a well. The apparatus comprises an upper pump and a lower pump. The lower pump creates a cone of depression which increases the amount of the floating layer within the well. The upper pump pumps the contaminant from the well or cone of depression. The upper and lower pumps preferably are gas-actuated pumps. The lower pump preferably includes an automatic switching device to activate the lower pump upon sensing a predetermined amount of fluid within the pump. A gas conduit interconnects the actuation chambers on both pumps such that when the lower automatic pump is provided with pressurized gas, the upper pump is simultaneously provided with the identical pressurized gas. Upon deactivation, both pumps relieve the activation pressure through the lower pump.

Abstract: A pump arrangement that has a pump chamber with an inlet opening and a discharge opening. A discharge pipe is connected to the outlet opening to carry liquid, etc., from the pump chamber. An inlet pipe is connected to the inlet opening and extends downwardly therefrom into the liquid to carry liquid, etc., to the pump chamber. The inlet opening is formed in the pump chamber above the discharge opening. A supply pipe is connected between a source of compressed air and the pump chamber. The supply pipe selectively either supplies compressed air to the pump chamber for exhausting liquid, etc., therefrom via the outlet opening and the discharge pipe or vents the air for intaking liquid, etc., into the pump chamber via the inlet pipe and the inlet opening. The inlet pipe is valve-free, whereby the inlet pipe is open during the entire operation of the pump arrangement so that the pump may pump liquids containing solid objects.

Abstract: A pump apparatus for pumping undergound fluids from a well. The pump includes inner and outer chambers, and a float slidable within the outer chamber. A source of compressed air is directed to a valve on the pump. The valve controls the flow of the compressed air into the outer chamber during the pumping cycle, and also controls the opening of a vent during the intake cycle. The float, while sliding up and down within the outer chamber in response to the fluid level within the chamber, activates the valve to begin the pumping of fluid when the chamber is full. When the chamber is empty, the float activates the valve is turn off the compressed air.

Abstract: A wet pump for pumping fish from a first fish receptacle to a second receptacle displaced from the first receptacle.

Abstract: A pump for liquid or slurry is valve controlled to fill a pumping chamber to an upper predetermined level; valve controlled to supply gas under pressure to the top of the liquid to force it out a lower outlet port down to a lower predetermined level and to alternate such cycles with all valves being located outside the chamber.

Abstract: A gas piston liquid flow controller comprising a pumping chamber of fixed volume, means to separately introduce into said chamber pressurized gas and liquid, means to detect the presence of liquid at predetermined upper and lower levels in said chamber, means to withdraw a stream of liquid from said chamber for delivery to a point of use and a controller to maintain liquid in said chamber to effect constant delivery of liquid to the point of use.

Abstract: There is provided a method and apparatus for removing liquid from a well using well bore pressurized gas. A U-shaped tube having a small orifice near the bottom thereof is received in the well. The upper portions of both legs of the tube are connected to well bore pressurized gas. A liquid sensor is received in one leg of the tube. When liquid flowing into the tube through the orifice rises to the level of the sensor, a valve, which is connected to one leg of the tube, is opened and the well head pressurized gas forces the liquid out of the tube and then out of the well.

Abstract: There is provided an improved fluid pumping device including an enclosure to be placed downhole in a well. A first hollow tube is received in the enclosure and extends to the surface of the well for removing fluid from the well. A second hollow tube also extends into the enclosure for forcing a gas into the enclosure. The bottom of the enclosure has an opening for permitting fluid to enter. A mechanical mechanism is provided for forcing the closing of the opening in the enclosure so that the device may be utilized in deep wells where high fluid pressures occur.

Abstract: Apparatus for transferring metered quantities of a flowable bonding agent from a tank into a mixer of a sand core making machine has an upright tubular vessel into which the bonding agent is drawn from the tank by a suction pump and a pressure pump which transfers the accumulated bonding agent from the vessel into the mixer. The vessel contains a float which cooperates with sensors serving to generate signals for actuation or deactivation of the pumps and/or valves in the conduits connecting the vessel with the tank, mixer and the pumps. The bonding agent is kept out of contact with the pumps and out of contact with the valves in the conduits connecting the vessel with the pumps.

Abstract: There is disclosed a pressure extraction pump system for recovering liquid hydrocarbons from contaminated ground water collected in a well. The pump system includes a pump with a pump vessel and an open top sleeve extending above the pump vessel for skimming the upper portion of the liquid collected in a well bore. The pump also includes a liquid level sensing device for sensing the level of the liquid in the sleeve and activating a pumping cycle. The pump also has a quick closing intake valve.

Abstract: A gas driven pump (102) is controlled by an asynchronous controller (101). The controller (101) has two control conduits (105,103) respectively in communication with the bottom and top regions of the chamber of the pump (102). Low pressure air is bubbled through the control conduit (105) in communication with the bottom region of the pump chamber; therefore, the pressure in that conduit, which is applied to the face top of the diaphragm (111), in a direct function of the depth of the liquid in the pump chamber. The other control conduit (103) is in communication with the bottom face of the diaphragm (111). When the difference of the pressures in the control conduits (105,103) exceeds the bias of the spring (114), the diaphragm (111) and the attached spool (128) move downward to activate a mechanically operated pilot valve (144). The pilot valve, in turn, releases supply air under pressure to switch the main valve (145) from the rest state to the operated state to initiate discharge of liquid by the pump.

Abstract: An apparatus for controlling the removal of liquid hydrocarbons from ground water in perforated well casings consists of a plurality of pump chambers and a control system which is powered by compressed air. The pump chambers are positioned above a liquid hydrocarbon recovery device which is positioned in the well casing at the oil/water interface. The pump chambers are evacuated, causing the ground water and the liquid hydrocarbons to be drawn into separate chambers through respective check valves. The pump chambers are then pressurized with air to push out the water and liquid hydrocarbons through check valves in the chamber discharge conduits, thereby removing the fluids from the well casing.

Abstract: A pump comprising an elongated housing adapted to be positioned in a landfill gas well. The housing has a peripheral wall, an interior chamber and apertures in the peripheral wall leading from the exterior of the housing to the chamber so that liquid can flow from the well into the chamber. A pressure responsive valve member is mounted in the chamber on the peripheral wall and extends across the apertures. A discharge conduit extends from the chamber to a location above the housing. When the liquid level in the chamber rises to a predetermined upper level, gas under pressure is supplied to the chamber. The gas under pressure causes the pressure responsive valve member to close the apertures and it forces the liquid out of the chamber through the discharge conduit.

Abstract: Water supply system comprising a unit for converting the wind energy into kinetic energy, a unit for converting the kinetic energy into another usable form of energy and a unit for supplying water driven by that usable form of energy. According to the improvement, the unit for converting the wind energy is a wind motor (1) having rotor blades (41) and a control mechanism (42) for constant load on the rotor blades (41) independently from the wind intensity, the unit for converting the kinetic energy is a device for compressing the air to a pressure greater than that of the atmosphere and the unit for supplying water comprises a natural or artificial source of water such as a well (21) or a container operated by pressurized air and structure for temporary storage of the water and for controlling the water bailing from the source of water.

Abstract: Ground water pollutant floating above the water table in a water-bearing formation is removed through a well penetrating the formation by lowering the water level so that pollutant from the region surrounding the well will flow into the well due to gravitational force, and lowering a liquid-retaining vessel into the well to a depth whereby a liquid entry port in the vessel is in the pollutant layer above the water level. The vessel is constructed to receive the liquid pollutant by gravitational flow through the liquid entry port, the displaced gas leaving through a vent. A compressed air line feeds the vessel to purge its interior of accumulated liquid through an exit port on an intermittent basis. Check valves associated with each port are actuatable by the influence of the compressed air to prevent leakage of discharged pollutant back into the vessel and to provide complete and efficient purging when the compressed air is flowing.

Abstract: A fluidic pumping system comprises a reverse flow diverter positioned below the level of a liquid to be pumped and inserted between a charge vessel and a delivery pipe. A control system including pressure-responsive devices effects alternate pressurizing and venting of the charge vessel for pumping the liquid. Passage of liquid from the charge vessel into pipes leading to a compressed air supply and the reverse flow diverter generates pressure changes which are detected and the electric output signals are used to operate the control means.

Abstract: A device for the selection, metering and delivery of treatment liquids for industrial laundry washers comprising a plurality of pumping units without positive displacement of pumping members. The pumping action is performed by a correlated combination of applications of pressure and vacuum on columns of the liquid that must be pumped. The delivery or pumping rate may be adjusted by setting on each pumping unit the quantity of the displaced material by sensing the displaced volume.

Abstract: A fluidic pumping system comprises a reverse flow diverter positioned below the level of a liquid to be pumped and inserted between a charge vessel and a delivery pipe. Control means including signal generating means, conveniently an ultrasonic transducer, effect alternate pressurizing and venting of the charge vessel for pumping the liquid. A pipe for the supply of compressed air to the charge vessel serves as a waveguide for the signals from the signal generating means.

Abstract: A device for controlling the performance of pumps, having a constant volume such as pneumatic pumps having a constant volume, comprises liquid level detectors, such as magnetic microswitches that cooperate with a magnetized float, and the detectors are adapted to control the filling and delivery operation of pumped liquid into and out of a pump body.The device may comprise three or more liquid level detectors and a timing device for the filling and/or delivery operation of the pump, at least one of said detectors being adapted to control said timing device and the other liquid level detectors being adapted to control the filling and delivery operation itself.

Abstract: A solar powered liquid metering device is disclosed including a solar chamber sealed from atmospheric pressure and partialy filled with a liquid to be metered. Trapped within the device above the liquid is an expansible gas. Also included is an overflow chamber partially filled with the liquid and coupled to the solar chamber to allow fluid communication between the two bodies of liquid. An overflow pipe has an end located within the overflow chamber. When the gas expands due to solar heating liquid is forced from the solar chamber into the overflow chamber and then out the overflow pipe. Various mechanisms are described to keep the liquid level within the overflow chamber no lower than the lip of the overflow pipe.

Abstract: A pressurized air pumping apparatus for pumping for example drilling mud and like viscous or slurry materials comprises a fluid receiving sump tank having an upper inflow opening and a valve seat at the opening. A discharge conduit at the lowermost portion of the sump tank discharges fluid to be pumped therefrom. A source of compressed air is provided by pressurizing the sump tank and a vertical conduit enters the tank and introduces pressurized air into the interior of the sump tank with the vertical conduit providing a discharge port for entering the compressed air into the sump tank. A valving member is movably mounted in preferably a sliding fashion within the sump tank upon the vertical conduit with the valving member sealing the conduit discharge port in the normal inoperative state while sump tank is receiving by gravity flow for example inflowing fluids to be pumped.

Abstract: For starting and stopping air injection, a pneumatic ejector for a liquid transport system typified by a municipal sewerage system is provided with an air release valve fitted with a limit switch as a control device.

Abstract: An efficient dredging device is disclosed, which includes a submersible pump having one or more chambers. Each chamber defines an air port through which air can be delivered to and exhausted from the chamber, and a material discharge port for discharging liquid and solid material from the chamber. A check valve is associated with the discharge port to prohibit the return of discharged material to the chamber. A chamber suction port admits liquid and solid material to the chamber, and a check valve prohibits the escape of material from the chamber through the suction port. Air control means are provided for cyclicly exhausting air from the chamber to admit material to the chamber through the suction port, and for delivering air to the chamber so as to discharge material from the chamber through the discharge port. A rotatable cutter member cuts material to be dredged, and pipes connect the cutter to the chamber discharge port.

Abstract: A system for pumping an abrasive or corrosive fluid at high pressure and with a variable delivery rate. The system comprises raising the pressure in a non-corrosive and non-abrasive liquid in a pressure raising means comprising pump means and at least two intermediate cylinders containing floating pistons. The pressure is transferred to the abrasive or corrosive fluid in pressure transfer vessels. A valve arrangement controls the flow of non-abrasive and non-corrosive liquid to the intermediate cylinders and return means are provided for returning the floating pistons after each stroke. The valve arrangement is controlled in dependence on the positions of the floating pistons in their intermediate cylinders.The system is particularly useful for supplying clay slurry to a high pressure plate filter press.

Abstract: A system for converting a constant pressure head of water into compressed air which may be utilized to transfer the potential energy of the pressure head to remote work sites.

Abstract: In an apparatus for the pulsewise dispensing of very small amounts of liquid controlled with a measuring instrument comprising an ejecting device for the pulsewise ejection of a desired amount of liquid, a pump is provided for supplying liquid to the vessel from a reservoir. The pump includes a neck portion having an inlet at the bottom thereof and a foot portion, with at least the foot portion immersed in a liquid contained in the reservoir. The foot portion has a volume at least as great as the refill volume of the measuring vessel and a feedline to the measuring vessel is disposed within the neck portion and terminates in proximity to the bottom of the foot portion. A check valve opens and closes the foot portion inlet by means of compressed gas which is controllable by sensing devices at the measuring vessel.

Abstract: A gas-operated liquid pump which includes an outer, stationary compartment and an inner compartment movable between upper and lower positions in the outer compartment. The inner compartment has positive buoyancy in the liquid to be pumped. Valve means operated by movement of the inner container is provided to cause gas admitted to the inner container to displace liquid therefrom when the inner container is in its upper position, and to permit gas to escape from the inner compartment when the latter is in its lower position. The pump makes use of a continuous stream of compressed gas such as air to provide a pulsating flow of liquid. The pump is useful in aquariums to create water movement or to pump water to a filter.

Abstract: A pneumatic sewage ejector includes a tank for holding fluid sewage. When the sewage reaches a predetermined high level in the tank, it is ejected by pressurized air forced into the tank through a valve located inside the tank. The ejection of the fluid is initiated by a float which responds to the high fluid level in the tank by ascending and thereby moving the valve to an air-input position to admit pressurized air into the tank to expel fluid. The valve remains in the air-input position until the fluid reaches a low level, at which time the float descends and moves the valve to a vent position to vent the pressurized air to the atmosphere. The float moves the valve between the air-input position and the vent position in one discrete step so that the valve cannot stop in an intermediate position.

Abstract: A latching liquid-level sensor including a vertically mounted free-floating float member which carries a magnet. A second magnet or ferromagnetic member separated from the first magnet by a liquid- and gas-impervious barrier is selectively actuated by the first magnet. The second magnet or ferromagnetic member is connected to a control logic system which is isolated from the float member which may be hermetically contained in a highly corrosive or explosive environment.

Abstract: The invention is concerned with an improvement in a gas pressure driven pump which comprises a vessel, means for introducing a liquid into the vessel, means for preventing reverse flow of the liquid into the liquid introducing means, means for introducing a pressurized gas to the vessel, and means responsive to a gas pressure increase in the vessel for flowing the liquid out of the vessel. The invention is an improved system for controlling the flow of pressurized gas into the vessel responsive to the liquid level therein, which system is substantially independent of the density of the liquid. More specifically the improved system comprises a valve having a first, a second and a third port, the valve providing a first mode in which the first port is in communication with the second port and a second mode in which the first port is in communication with the third port. The second port communicates in both modes with the surrounding outside atmosphere.