Abstract: A method for operating an internal combustion engine having at least one fuel injector that is activated for opening and closing via a solenoid valve of a respective fuel injector. Commencing with the activation of the fuel injector for opening, structure-borne sound waves emitted by the fuel injector over the time are detected by measurement. A structure-borne sound wave signal detected by measurement over the time is evaluated such that dependent on the amount of at least one maximum of the structure-borne sound wave signal and/or dependent on the number of the maximums of the structure-borne sound wave signal and/or in the presence of multiple maximums dependent on the time sequence and/or on the amount of the maximums, an operating state of the respective fuel injector is deduced.

Abstract: A compressor capacity control method and a device is provided. The changeover from a loading state regarding the compressor to an unloading state regarding the compressor and vice versa is controlled, whereby, during a time span from a starting time point when the compressor operation state changes into an unloading state to a time point when a loading/unloading operation-cycle is finished and a predetermined time duration has passed after the starting time point, the time cycle control is performed so that the loading state is changed into the unloading state, at a time point when the predetermined time duration has passed. Further, the discharge pressure of the fluid discharged from the compressor is detected so that the loading state is changed into the unloading state in a case where the discharge pressure exceeds a prescribed upper limit pressure.

Abstract: A snowmobile having an electronic oil pump fluidly connected to an oil tank thereof is disclosed. The electronic oil pump is fluidly connected to an engine of the snowmobile for delivering lubricant to the engine. An electronic control unit is electrically connected to the electronic oil pump for controlling actuation of the electronic oil pump. A method of operating an electronic oil pump is also disclosed.

Abstract: In a variable displacement oil pump employing a return spring for forcing a cam ring in a clockwise direction, and a control chamber configured to displace the cam ring in a counterclockwise direction with a discharge pressure introduced thereto, a pilot valve is provided to selectively switch between an oil-discharge from the control chamber and an oil-introduction to the control chamber by moving a spool in one direction by a biasing force of a valve spring or by moving the spool in the other direction against the biasing force by the discharge pressure and applied at an oil introduction port of the pilot valve. Also provided is an electromagnetic valve configured to variably control timing at which switching between the oil-discharge and the oil-introduction occurs, with respect to the discharge pressure applied at the oil introduction port, by appropriately changing the preload setting of the valve spring.

Abstract: Apparatuses and methods for constructively utilizing pressure pulses to enhance the volumetric efficiency of a reciprocating compressor are provided. An apparatus includes a gas circulation device and a controller. The gas circulation device provides a path through which the gas circulates between a reciprocating compressor and a volume bottle buffering the reciprocating compressor from an installation. The gas circulation device is configured to have a resonance frequency substantially equal to a frequency of the performing compression cycles in the reciprocating compressor. The controller is configured to control timing of switching a valve located between the reciprocating compressor and the gas circulation device in order to constructively use pressure pulsations occurring in the gas circulation device, to enhance the volumetric efficiency of the reciprocating compressor.

Abstract: The present invention relates to an apparatus having at least one hose roller pump, wherein the hose roller pump has at least one pump bed and at least one hose or hose part inserted or insertable into the pump bed, and having at least one pressure detection means which is arranged downstream of the hose roller pump and by means of which the time extent of the pressure of a fluid conveyed by means of the hose roller pump can be determined, and having at least one evaluation means by means of which the occlusion of the hose or hose part inserted or insertable into the pump bed can be monitored with reference to the time difference and/or to the angular difference between at least one maximum and at least one minimum of the determined time extent of the pressure and/or with reference to a local minimum of the determined time extent of the pressure. The invention furthermore in particular relates to a method therefor.

Abstract: A compressor drive torque estimating device to be adapted for a system provided with a refrigeration cycle in which a refrigerant is circulated by a compressor driven by a drive source mounted in a vehicle, comprising heat load detecting means for detecting a heat load of the refrigeration cycle, a storage unit storing a plurality of estimated drive torque characteristics establishing correlation between a drive torque change characteristic of the compressor and an elapsed time from a time of start of operation of the compressor, an estimated drive torque characteristic selecting means for selecting the one of the plurality of estimated drive torque characteristics stored in the storage unit based on detected values detected by the heat load detecting means, and an estimated drive torque calculating means for calculating an estimated drive torque of the compressor based on the estimated drive torque characteristic selected by the estimated drive torque characteristic selecting means.

Abstract: When employing synthetically commutated hydraulic pumps (1), a time delay between a change in fluid flow demand (15) and the resulting fluid flow output (13) can be observed. It is suggested to use a time evolvement function, taking into account the time evolvement of the fluid flow demand and/or the time evolvement of the pumping strokes, to modify the actuation of the electrically commutated valves.

Abstract: A lightweight portable garden container consists of a space frame that supports a flexible waterproof liner such that the floor of the flexible liner is elevated above the ground. The flexible liner includes a plurality of drain holes formed in the bottom surface that are attached to a manifold for collecting water draining from the flexible liner. The manifold drains into a closed reservoir which is attached to a pump that recirculates water from the reservoir back into to the container for irrigating the plants growing therein. The raised floor facilitates gardening at a comfortable level, while the recirculation system minimizes the amount of wasted water.

Abstract: A high pressure fuel pump with parallel cooling fuel flow is disclosed wherein a fuel pump barrel having a substantially cylindrical plunger bore with an annular drain groove is provided. A first fuel path is provided that fluidically couples a fuel supply to an annular cooling ring formed on the outer surface of the barrel. The first fuel path further fluidically couples the annular cooling ring to a storage tank via an exit passage. A second, parallel fuel path is provided that fluidically couples the first fuel path to the drain groove, and further includes a drain passage fluidically coupled to the drain groove and the first fuel path via the storage tank.

Abstract: An exemplary hydraulic system includes a first digital valve fluidly connectable to a first hydraulic load and a pump. The first valve is operable to fluidly connect the first hydraulic load to the pump. A second digital valve is fluidly connectable to a second hydraulic load and the pump. The second valve is operable to fluidly connect the second hydraulic load to the pump. The system includes a first sensor for detecting a pump discharge pressure and a second sensor for detecting an inlet pressure of the first hydraulic load. A controller is configured to determine a time delay based on the pump discharge pressure and the first hydraulic load inlet pressure and to send a control signal instructing the second valve to commence opening at a time substantially equal to the time delay after commencing closing the first valve.

Abstract: Apparatus and method for releasing a stuck inlet check valve of a paint pump including a solenoid connected to the check valve with a pusher element which momentarily displaces a moveable element such as a ball in the check valve to break any adhesion between the movable element and a valve seat. A control provides a single pulse of energy to the solenoid each time power is applied to the pump. The control includes an SCR connected between a full wave rectifier and a coil of the solenoid, with gate current removed from the SCR to commutate the SCR after a predetermined time interval after power is applied.

Abstract: A two-stage pressure relief valve for use with hydraulic systems is disclosed. The two-stage pressure relief valve has a first stage that relieves increases in hydraulic system pressure over the normal operating pressure and up to a selected threshold pressure level, and a second stage that brings the hydraulic system pressure down to a selected reduced operating pressure that is below the normal operating pressure in response to increases in the operating pressure over the threshold pressure level.

Abstract: A method for controlling a thick matter pump comprising two delivery cylinders (10) emerging, via two openings (12), into a material reservoir (14), associated with two delivery pistons (26), symmetrically synchronized relative to said cylinders, and a branch pipe 18 arranged inside the material reservoir (14), capable of being connected, on the input side, alternatively to one of the openings of the delivery cylinders with exposing of the other opening, the output side connected to a conveyance conduit (20). When the pumping is interrupted, thick matter, liquid concrete for example, is sucked up, via the delivery cylinder temporarily communicating with the reservoir, and is delivered, via the other cylinder (10), connected to the branch pipe (18), so as to form a column of thick matter through the delivery pipe (20), towards its output.

Abstract: An automatic inlet control mechanism and air compressor unit include a valve cavity and valve outlet. The valve cavity includes a valve control chamber and valve inlet chamber. A valve piston assembly is positioned between the valve control chamber and the valve inlet chamber to prevent the flow of air between therebetween. The valve outlet allows air to flow from the valve inlet chamber into the compressor unit. The valve piston assembly prevents air from flowing from the valve inlet chamber to the valve outlet when the compressor unit is not drawing air. A vent passageway allows air to flow between the valve control chamber and the compression cylinder inlet when compression is begun at the start-up of the compressor unit or at the loading of the idling compressor unit. A vent orifice restricts the flow of air from the valve control chamber to the compression cylinder inlet.

Abstract: A compressor assembly having a first compression mechanism operatively coupled to a first motor and a second compression mechanism operatively coupled to a second motor. The first compression mechanism compresses the vapor from a low pressure to an intermediate pressure and the second compression mechanism compresses the vapor from the intermediate pressure to a discharge pressure. An electrical circuit supplies electrical current to the first and second motors during operation of the compressor assembly. The electrical circuit includes means for, during start-up of the compressor assembly, initiating the supply of electrical current to the first motor at a first time and initiating the supply of electrical current to the second motor at a second time wherein the first time precedes the second time by a time lapse.

Abstract: Disclosed are an air conditioning system with two compressors and a method for operating the same, so as to variably change a compression capacity of a refrigerant according to the variation of cooling load. Herein, when a full operation order is inputted to the two compressors in order to satisfy increased cooling load, the first compressor is first operated, and then the second compressor having a compression capacity of a refrigerant smaller than that of the first compressor is additionally operated, so that a current peak value for operating the compressors does not exceed an allowable current range of a circuit breaker installed in a home or building, thereby safely controlling the air conditioning system and simultaneously allowing the current to be provided to other electric appliances, thus improving users' convenience.

Abstract: When a compressor apparatus is operated at a maximum displacement for 60 minutes or longer, an ECU controls a pressure control valve to gradually change the refrigerant pressure in a swash plate chamber in a manner that gradually reduces the displacement of the compressor apparatus. In this way, it is possible to create a state, in which a relatively large pressure difference is created between a refrigerant inlet side and the swash plate chamber. Thus, refrigerant oil accumulated in the swash plate chamber can be returned to the refrigerant inlet side of the compressor apparatus at the time of gradually reducing the displacement of the compressor apparatus.

Abstract: A metering assembly includes a motor removably coupled to a pump using a flange clamp. An annular connection flange is provided at one end of the motor housing; and a cooperating annular connection flange is provided at one end of the pump housing. The connection flanges have opposed, mating end surfaces which are located in flush relation with each other. The flange clamp includes a pair of arcuate clamping arms which are pivotally supported at one end, and a locking member connecting the other, distal free ends of the arms together, and which can be manually tightened and untightened, so that the flange clamp can be easily located around and tightened down around the annular connection flanges of the pump and motor to create a mechanical face seal between the pump and motor.

Abstract: A diaphragm metering pump suitable for metering an effervescent gas. The pump has a pump head with a product chamber having an inlet end with a one-way inlet valve and an outlet end with a one-way outlet valve. A displaceable diaphragm member defines a boundary of the product chamber. The diaphragm member is capable of being reciprocated to cause pumping displacements. A discharge side is disposed downstream from the outlet valve. A passageway is disposed in fluid communication between the discharge side and the product chamber. A valve is disposed in the passageway. The valve is opened intermittently to allow liquid to re-enter the product chamber in an amount effective to purge gas from the product chamber to prevent loss of prime.

Abstract: A combination including a diffusion pump and a reservoir for working fluid positioned remotely from the pump and connected to the diffusion pump via a valve and pipework.

Abstract: A rod body (30) is formed of magnetostrictive material and includes one end portion (30a) fixed, and a piston (35) is fixed to the other end portion (35b) of the rod body (30). The piston (35) is slidably disposed within a cylinder (36) in which there is formed a pump chamber (37). A suction port (39) for sucking lubricating oil into the pump chamber (37) is formed in the cylinder (36), while a suction valve (40) for preventing the lubricating oil from flowing out from the suction port (39) is disposed in the suction port (39). In the cylinder (36), there is disposed a nozzle (20) which communicates with the pump chamber (37) and has a sectional area smaller than the lubricating oil passage sectional area of the suction valve (40). There is disposed a coil (43) outside the rod body (30) and, to the coil (43), there is connected a control device (6) for controlling the supply of a current to be supplied to the coil (43).

Abstract: The present invention is directed to a method of reducing cooling capacity in a rotary vane compressor in such a way that the power requirement to drive the rotor is reduced to the same extent (or close to) as capacity is reduced. An economizer port operating in economizing and unloading cycles is located in the compression region at a point after the compression chamber has been closed for the compression and at a point where sufficient both unloading (reducing) and economizing (increasing) capacities are provided. A valve is associated with the economizer port, the valve body being formed from a part of the stator body. A seat of the valve in the closed position is shaped to be contiguous with the wall portion of the stator. In an opened position the valve provides conmumnication between the compression chamber and an external portion of the economizer port.

Abstract: A rod body 30 is formed of magnetostrictive material and includes one end portion 30 fixed, and a piston 35 is fixed to the other end portion 30b of the rod body 30. The piston 35 is slidably disposed within a cylinder 36 in which there is formed a pump chamber 37. A suction port 39 for sucking lubricating oil into the pump chamber 37 is formed in the cylinder 36, while a suction valve 40 for preventing the lubricating oil from flowing out from the suction port 39 is disposed in the suction port 39. In the cylinder 36, there is disposed a nozzle 20 which communicates with the pump chamber 37 and has a sectional area smaller than the lubricating oil passage sectional area of the suction valve 40. There is disposed a coil 43 outside the rod body 30 and, to the coil 43, there is connected a control device 6 for controlling the supply of a current to be supplied to the coil 43.

Abstract: A compressor adapted to be put into a load operating state when there exists the relation Pd≦PSL between the discharge pressure Pd and a set lower limit of pressure PSL and adapted to be put into an unload operating state when there exists the relation Pd≧PSH between the discharge pressure Pd and a set upper limit of pressure PSH, or when there exists the relation PSL<Pd<PSH among the discharge pressure Pd, the set upper limit of pressure PSH, and the set lower limit of pressure PSL and, in addition, there exists the relation Tc≧Ts between the count time Tc indicated by a timer to be started when a preceding unload operation is started and a set time Ts.

Abstract: A combination electric motor driven vacuum pump and air compressor unit, particularly adapted to use in medical procedures, is mounted in an insulated cabinet arranged to provide for drawing cooling air into the cabinet through an inlet duct, cause cooling air to flow over an aftercooler part of a compressed air discharge conduit to aftercool compressed air, and cause cooling air to flow through the pump/compressor unit and be discharged from the cabinet. A pressure air receiver tank is mounted in the cabinet and is operably connected to a condensate receiver and a control valve for discharging condensate to an evaporator container connected to the aftercooler conduit part to evaporate condensate. A control circuit includes solenoid actuated valves for controlling vacuum produced by the pump/compressor unit and actuation of a flexible tube clamp mechanism for cutting off vacuum from a vacuum device, such as a cannula, during certain phases of a liposuction medical procedure, for example.

Abstract: A hydrualic power unit for an auto-hoist lift having a more compact motor and improved noise characteristics. The power unit having a reservoir with a closed end and an open end. A manifold attached to the open end and having an inlet port and an outlet port with a hydrualic circuit located between the ports. The hydrualic circuit having a delay valve for reducing the start-up torque load on the motor, thereby allowing the motor to be sized for normal operating requirements rather than oversized for start-up requirements. The power unit may further include a motor and pump located inside a hydrualic fluid reservoir to thereby reduce the amount of noise reaching the immediate vicinity of the power unit. The motor and pump are submerged in the hydrualic fluid to advantageously utilize the hydrualic fluid to cool the motor.

Abstract: In a method of and a device for suction transporting a material from an object surface, the suction transporting device has a suction unit and a unit for modulating the suction. A suction is applied to a transporting line by the suction unit so that a material is transported through the transporting line from an inlet to an outlet. A suction force of the suction produced in the transporting line is modulated by communicating an interior of the transporting line with atmosphere through a passage and periodically changing the area and the shape of the passage during the transporting. The frequency of the modulation is changed in dependence on the distance between the inlet of the transporting line and the object surface.

Abstract: In a high-pressure cleaner of the type comprisinga) a high-pressure pump (3),b) a motor driving said pump (3),c) a liquid supply (1,2) connected to the suction side (8) of the pump (3),d) a cleaning gun (4) connected to the delivery side (6) of the pump (3) through a delivery duct (10) and comprising a manually operable stop valve, ande) a bypass valve (16,17) adapted to in its open condition to allow flow frem the delivery side (6) to the suction side (8) of the pump (3),the main novel feature isf) flow-sensing mechanism (15,20) associated with the delivery duct (10) and adapted to open the bypass valve (16,17) when flow in the delivery duct ceases or decreases below a predetermined magnitude and to act upon it in the closing direction when flow is equal to or above the predetermined magnitude.

Abstract: A fluid delivery system is disclosed which includes a pump and a fluid delivery set. The fluid delivery set includes a stop cock valve, and the pump includes a valve actuation unit into which the stop cock valve is positioned for operation of the system. The valve actuation unit includes a valve receiving mechanism which requires the valve to be closed in order to be inserted into or removed from the valve actuation unit, thereby preventing accidental free flow of fluid at all times. The fluid delivery set may also include an auxiliary fluid source to allow periodic flushing of the fluid delivery line, and the valve actuation unit can be programmed by the pump to automatically initiate periodic flushing cycles if desired.

Abstract: A device for reducing pressure in a compressor when it is in the idling and shut-down mode, in the induction manifold of which there is an induction control valve that controls the passage through the induction manifold, is provided with a bypass line that incorporates a closeable relief valve. The device for reducing pressure incorporates a spring-loaded pressure keeper valve that can be adjusted to the desired pressure, and an additional second relief valve that is arranged in parallel to the first relief valve. This second relief valve is acted upon by the pressure immediately upstream of the compressor in the induction manifold, and opens an additional relief path as soon as this pressure exceeds a pro-determined level when the compressor is shut down. The two relief valves and the pressure keeper valve can be incorporated into a common housing.

Abstract: In a method of injection fuel for Diesel engine comprising a high pressure injection pump with a fuel supply line for supplying high pressure fuel to fuel injection nozzles wherein a fuel control line extends between the pump and a low pressure fuel supply line for discharge in excess fuel thereto under the control of a magnetic valve which is closed to end the discharge of excess fuel and initiate pumping of fuel, the magnetic valve is opened at the end of fuel pumping at a point corresponding to a piston stroke length h after the upper dead center of the piston such that, when communication between the pump and the low pressure fuel line is established, pressure pulses in the low pressure fuel line are avoided.

Abstract: An apparatus is provided for supplying vacuum and compressed air utilities for dental and medical applications. The apparatus comprises a reciprocating piston air compressor for simultaneously producing vacuum pressure at an intake valve thereof and compressed air at an exhaust valve thereof, the vacuum being used to draw air, water vapor, and effluent such as bodily fluids and tissue through a conduit. Effluent and water vapor are separated from the air stream and discharged into a drain. The desired vacuum is maintained by a regulator carried by the compressor. A receiver is also carried by the compressor for receiving and storing the compressed air from the compressor.

Abstract: A vacuum system comprises, as an integral assembly, a turbomolecular pump with drive motor, a vent valve, a purge valve, a roughing valve, a heater and an electronic control module. The control module has a programmed processor for controlling the motor and valves and is user programmable for establishing specific control sequences. The integral electronic control module is removable from the assembly and is connected to the other devices through a common connector assembly. Proper introduction of a purge gas through the purge valve is detected by detecting the current load on the pump drive or by detecting foreline pressure. To test the purge gas status, the purge valve may be closed and then opened as drive current or pressure is monitored. After power failure, the controller will continue normal drive of the turbomolecular pump so long as the speed of the pump has remained above a threshold value. Otherwise the vent valve will have been opened, and a start-up sequence must be initiated.

Abstract: A fluid transfusing device and method of control therefor includes a plurality of pump driving portions and a microprocessor. Each pump driving portion is for driving a pump, and the microprocessor controls the pump driving portions. The microprocessor executes a fluid transfusing device control program, and interrupts the fluid transfusing device control program upon receiving a pump interrupt. The microprocessor then executes a pump driving interrupt module. When the microprocessor executes the pump driving module, the microprocessor generates a pump driving pulse to control a pump driving portion associated with the pump corresponding to the pump interrupt, determines receipt of another pump interrupt corresponding to a another pump, and generates a pump driving pulse to control a pump driving portion associated with the another pump corresponding to the another pump interrupt.

Abstract: This invention relates to an air compressor and in particular to one which includes a valve controlling device having a check valve and a cover. The check valve is fixedly mounted on said cover and is connected with a pipe. The check valve including a spring, a ball and a packing with the spring urging said ball against said packing thereby sealing said pipe. The cover is fixedly mounted on a cylinder so that air in said cylinder can flow out of said cover. A passage is formed between said cylinder and said cover and communicated with said check valve, a power breaker, an exhaust valve, and a pressure gauge. The power breaker is fixedly connected with said cover has via a connector and having an adjusting knob, a diaphragm, a main body, and two conducting members. The main body has an interior chamber in which is fitted a piston, the piston receiving a spring and having a protuberance on which is fitted a circular conductor.

Abstract: In a compressor control system, a subcontroller is coupled with the master-controller in order to detect, when the bypass valve is being modulated, whether there is a deviation between the minimum inlet valve position assigned to the system and the actual inlet valve position. In such case, correction of the inlet valve position is automatically effected by the subcontroller in either direction to restore the minimum assigned inlet valve position.

Abstract: A pressure control apparatus suitable for controlling pressures in autoclaves permits a plurality of autoclaves to be selectably pressurized from a single pressurizing circuit. The apparatus can be externally controlled to more efficiently multiplex autoclaves to the pressurizing circuit and to more efficiently implement different pressure schedules for the autoclaves. Once a pressure has been set for an autoclave maintained in communication with the main pressurizing circuit, the apparatus automatically monitors the position of the pump piston and resets it from either of its extreme limits of movement to maintain pressure at a desired set point. Corresponding methods are also disclosed.

Abstract: An air compressor is controlled such that when the pressure inside a tank for storing compressed air reaches a predetermined lower-limit value, the compressor is brought into a load running state to supply compressed air to the tank, whereas, when the pressure inside the tank reaches a predetermined upper-limit value, the compressor is brought into a stand-by state to suspend the supply of compressed air to the tank. The air compressor has a controller which judges the change in pressure inside the tank when the compressor is in a load running state on the basis of a signal delivered from a pressure sensor and effects control such that either one of two operations modes, that is, an intermittent operation mode in which the compressor stands by with the supply of electric power from a motor being cut off and a continuous operation mode in which the compressor stands by in a no-load state with the motor being supplied with electric power, is selected subsequent to a stand-by state.

Abstract: Provided are a pair of pumps, each of which comprises a bellows having an intake inlet and a discharge outlet, a reciprocating drive means for contraction and expansion movements of the bellows, and a couple of electro-magnetic on-off valves disposed respectively in the intake inlet side and discharge outlet side of the bellows, so that, during the contracting motion of the bellows, the electro-magnetic on-off valve in the intake inlet side becomes closed while the electro-magnetic on-off valve in the discharge outlet side becomes open, and during the expanding motion of the bellows, the electro-magnetic on-off valve in the intake inlet side becomes open while the electro-magnetic on-off valve in the discharge outlet side becomes closed. The paired pumps perform the discharge motions alternately. The discharge outlets of the pumps at their ends are fluidly connected via a directional valve with a discharging gun.

Abstract: A capacity control device for a screw compressor provided with a capacity control passage and a slide valve adjusting the opening thereof, wherein the slide valve is driven in a closing direction due to a pressure difference between a high pressure and a low pressure and is moved in an opening direction thanks to function of a spring when the high pressure is balanced with the low pressure, and when the pressure difference between the high pressure and low pressure is lower to cause the slide valve to be open thanks to the function of the spring, the slide valve is moved in the closing direction against the spring by use of pressure in a compression-processing part in the screw compressor, thereby enabling to quickly transit from no load condition to a loaded condition.

Abstract: In operating high-pressure cleaning units, the outflow of the water discharged from the associated pump (6,8) may be temporarily interrupted. As the pump normally operates continuously, care must be taken to ensure that the water can then be returned in a bypass to the pump's suction side. This can be achieved by a bypass valve sensing a rising pressure in the said closing situation, thus opening for the bypass. Correspondingly, the bypass valve (36,44,32) senses a declining pressure when the discharge or ejection is resumed, thus causing a block to the bypass (40). However, a corresponding, declining pressure occurs when the pump is stopped, for which reason the bypass valve will block the bypass also in this condition. Thus, the result is that during the stopping process determined by the pump's inertia a substantial and dangerous pressure may build up in the discharge conduit (26) from the pump.

Abstract: A reciprocating ram pump of the well known Willett's type is provided with electrical sensors (S1 and S2) and a solenoid operated valve (56) for controlling reversal of the ram at its delivery and suction stroke limits. The sensor outputs are employed for the purpose of counting the number of strokes executed by the ram in a counting circuit (22) which can be preset by means of keyboard (26) to count until a stroke count corresponding to the preset value (or a threshold value close thereto) as been reached whereupon a warning signal may be produced. The number of strokes counted may be indicated on display (28) for example after conversion into a parameter such as total volume delivered. The preset value entered from the keyboard (26) may likewise be displayed. The sensor outputs may additionally be employed to control a timing circuit (24) which can be preset to time a certain interval corresponding to the delivery stroke rate of the pump falling to or below a certain level.

Abstract: Pulses produced by a pulse generator coupled to the output shaft of an electric motor that reciprocates a polish rod of a well pumping system are counted by a computer to locate the polish rod at a series of positions during each reciprocation of the polish rod and the dynamic load on the polish rod at each of these positions is determined by the computer from the time difference between pulses. The pulse count and dynamic loads are simultaneously displayed on a two-dimensional array of light emitting diodes under the control of the computer to visually present the dynamic pumping characteristics of the system. The operation of the system following pump off or breakage of a sucker rod is interrupted by controlling the operation of the motor via the computer, the computer switching off the motor following the occurrence of a preselected set of dynamic loads for a preselected set of pulses.

Abstract: The invention comprises a valve contained in a drainage line from a compressor tank and a control for operating the valve. The control includes a timer which comprises an air storage tank, an air bleed valve for bleeding the storage tank and structure for operating the valve in response to air pressure received from the air storage tank. The timer operator is initiated in response to deactivation of the compressor motor.

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 compressor having a starting load reducing apparatus comprises a main compressor body for compressing gas obtained under suction from an intake chamber through an intake valve within a compression chamber, and ejecting the compressed gas through an outlet opening, a motor for driving the main compressor body, a switch for starting the motor by closing, a solenoid mechanism operated by the closing of the switch, for forcibly communicating the compression chamber with the intake chamber, to put the main compressor body into a non-compressing operational state, and a positive thermally sensitive resistor element connected at a stage before a coil of the solenoid mechanism. The solenoid mechanism operates after the switch is closed until the time when the resistance of the positive thermally sensitive resistor element reaches a predetermined resistance.

Abstract: This liquid flow control apparatus is a delayed closure valve mechanism intended for use in an unloading bypass between the outlet and the inlet of a pump for supplying fuel to an oil burner. The valve mechanism includes a conduit having a large diameter section between two small diameter sections. A ball valve having a diameter smaller than the large diameter section and larger than the two small diameter sections is captured within the large diameter section. The large diameter section extends upwardly, so that the ball is biased by gravity to its inlet end. When the pump starts, the ball is moved by the discharge pressure of the pump until it engages the upper end of the large diameter section, whereupon the unloading bypass is closed and the discharge pressure of the pump is effective to open a cut-off valve leading to the nozzle of the oil burner. The length of the large diameter section determines the time delay between the starting of the pump and the delivery of oil to the nozzle of the burner.

Abstract: An electronic control system for sequential actuation of a four-way solenoid valve is used to selectively load and unload a slide valve control for a screw compressor. The electronic control system can be responsive to output or refrigerant pressure or evaporator pressure or inlet pressure and pulses a four-way solenoid valve to selectively load and unload the compressor so that it will maintain system pressure within a preselected deadband. Selective pulsing of the four-way solenoid valve is used to gate hydraulic fluid to load and unload chambers separated by a piston coupled to a slide valve which shifts longitudinally and changes the capacity of the screw compressor. The control system senses system pressure (reflecting load), and when a limit pressure is reached, a gas bypass solenoid valve (or dump valve) and fast-unload system is actuated to entirely unload the compressor. The control circuit also monitors current to the motor which drives the screw compressor.

Abstract: A rotary oil sealed compressor including an unloader valve to restrict or close the compressor intake when the compressor pressure rises above the normal working pressure (i.e. when the demand for compressed air drops or ceases) and a minimum pressure valve arranged to ensure that the pressure within the compressor never drops below a predetermined minimum value, further includes venting means responsive to the rise in pressure in the compressed air supply line above a predetermined value exceeding the normal working valve arranged to vent the delivery and compression spaces of the compressor. Thus under no-load conditions the pressure within the compressor is reduced to a relatively low level which considerably reduces the power consumed when the compressor is idling.