Abstract: A grout slurry pumping system, and a grout slurry control box and associated tools are described. Methods of using the pumping system and control box are also described. The pumping system and control box may be used separately or together. The pumping system maintains a grout slurry of desired consistency and can provide it through a hose to remote locations. The control box operates to apply grout to a work surface in desired quantities and in desired amounts according to a control valve.

Abstract: An oil-free dry screw compressor system is provided and includes a variable speed drive and motor along with control logic to increase or decrease the speed of the drive and motor based on sensed pressures. By using an electric motor and a rectifier/inverter drive, a variable speed compressor system is provided having a drive system that can be stopped and started an unlimited number of times over a given time period. Methods of controlling pressure in a compressor system including an oil-free dry screw compressor are also provided.

Abstract: An apparatus for and a method of evacuating a vacuum chamber (process chamber) or the like of a semiconductor fabrication facility, for example. The evacuating apparatus has a vacuum chamber to be evacuated, a discharge pipe connecting the vacuum chamber to an atmospheric port, a vacuum pump connected to the discharge pipe and operable at a variable rotational speed, and a controller for controlling the rotational speed of the vacuum pump.

Abstract: The invention relates to a method for controlling a compressor installation with at least one lubricated screw-type compressor element (1) connected to a pressure vessel (11) which is driven by an electric motor (10) which is regulated in function of the compression pressure, and which compresses the gas supplied through the gas inlet conduit (2). The return flow of lubricating agent through the return conduit (7) also is determined by a controlled valve (9) which is provided with a calibrated opening (29) and which is controlled by control means (43) which, as the number of revolutions of the screw-type compressor element (1) has dropped below a well-defined value, put the controlled valve (9) into the position in which it restricts the return flow of lubricating agent to a flow through the calibrated opening (29).

Abstract: A vacuum system comprises, as an integral assembly, a vacuum pump with drive motor, a purge valve, a roughing valve and an electronic control module. A cryogenic vacuum pump and a turbomolecular vacuum pump are disclosed. 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. In the turbomolecular pump system 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.

Abstract: A pump assembly that has a control circuit and a pressure switch which control the operation of a pump motor. The motor drives a positive displacement pump that is coupled to a fluid system. The control circuit includes a pulse width modulator circuit. The control circuit is activated when a pressure switch senses that a line pressure of the fluid system is below a threshold value. The control circuit can either operate in a continuous mode to provide a constant signal to the motor, or a pulse regulating mode to provide a series of pulses to the motor. The pulses begin with a minimum width and gradually increase until a predetermined current limit has been attained, or the motor reaches a full speed with the control circuit in a continuous on state. The speed of the motor will then correspond to the flow demanded by the fluid system. The energy provided by the pulses is varied as a function of changes in peak current drawn by the motor. The peak current is sensed and used to determine the pulse width.

Abstract: A method for compensating the offset of a pressure value having the steps: detecting a pressure value, lowpass filtering of the pressure value, storing the lowpass filtered pressure value as an offset value, the lowpass filtered pressure value being stored as an offset value if at least the condition is present that a logical signal has or assumes a first value and a substitute value is stored as an offset value if the logical signal has or assumes a second value. Also described herein is a device for compensating the offset of a pressure value.

Abstract: An electronic control system dynamically varies the output capacity of a compressor by controlling plural valves associated with the compressor to provide pressurized air to a distribution system at an appropriate rate. The control system operates in any of three modes for standalone operation, including continuous run, auto/dual pressure band, and target pressure modes. In the first two modes, pressure bands are dynamically calculated based on load and unload values entered by an operator. These electronic control systems can also be connected in a peer-to-peer network to coordinate control of up to 16 compressors feeding the same distribution system, so as to maintain a desired target pressure in the system. A modem connected to the system supports remote diagnostics, monitoring, and control. Specialized startup, operating, and shutdown diagnostic algorithms prevent damage to the compressor and avert unsafe operating conditions.

Abstract: A vacuum system comprises, as an integral assembly, a vacuum pump with drive motor, a purge valve, a roughing valve and an electronic control module. A cryogenic vacuum pump and a turbomolecular vacuum pump are disclosed. 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. In the turbomolecular pump system 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.

Abstract: A controller for managing a plurality of compressors in an efficient manner such that the system uses less energy, has lower maintenance cost and experiences less wear. For a system with multiple compressors the controller has the minimum number of compressors needed to maintain the pressure on at any given time and has no more than one compressor running in an unloaded condition for maximum efficiency. The system can quickly pressure up or down in conjunction with the needs of the system. The controller rotates the order of use of the compressors to spread the time of use and for limiting the number of times during an hour that each compressor can be turned on such that the compressors take turns running and turning on and off for even wear. The system seldom uses more than one compressor unloaded at any time.

Abstract: A fluid pump having a motor operably coupled to a pump assembly, the motor and pump assembly acting cooperatively to pressurize a fluid includes a pressure switch being in communication with the fluid under pressure and being in communication with the motor for sensing the fluid pressure and controlling the operation of the motor to maintain a selected fluid pressure. A method of controlling fluid pressure in a fluid pump, the fluid pressure being generated by activating a pump motor to operate a pump assembly.

Abstract: The invention relates to a system for regulating the pressure in an enclosure (1) that is to contain processed gas for manufacturing semiconductor components or micro- or nano-technology devices, the enclosure being connected by pipework (2) to a pump unit (3) comprising a dry mechanical primary pump (4) and at least one secondary pump (5). According to the invention, the system further comprises a speed controller (6) controlling simultaneously the speeds of rotation of the dry mechanical primary pump (4) and of said at least one secondary pump (5).

Abstract: Flow parameters in a fluid delivery assembly are determined by monitoring pressure responses and processing those responses along with information regarding the fluid flow. In one aspect, a processor controls the pump to pump flow quantities in accordance with a pseudorandom code. Portions of the resulting pressure signal sensed at the conduit is averaged, and the averaged values are then decoded in accordance with the pseudorandom code. An estimate of the equilibrium pressure is generated from the decoded average pressure values, while a summation of the pressure samples is generated from the undecoded pressure signals. The resistance to fluid flow of the system is determined from the estimated equilibrium pressure and pressure summation. For low flow rates, a processor controls the pump to pump fluid in a series of fluid boluses, with each fluid bolus delivered in the beginning of a separate timeslot.

Abstract: An electronic pressure sensor is incorporated into a discharge pressure portion of a compressor. If the pressure sensor indicates that the discharge pressure exceeds a maximum value, the operation of the compressor motor is stopped. The pressure sensor preferably sends an electronic signal to a microprocessor such that the pressure can be compared to a predetermined maximum value. The pressure sensor includes a transducer to change the sensed pressure to a voltage value. The microprocessor communicates with a first switch, which may be a triac switch, and which stops operation of the compressor motor should an undesirably high value be detected. In addition, a second switch communicates with a comparing circuit which ensures the voltage from the pressure sensor is between a minimum and maximum value. The purpose of the comparing circuit is to ensure proper operation of the pressure sensor and its associated circuit.

Abstract: A safety circuit for use with a spa system includes a pressure sensor which generates a signal representative of the pressure in the system. The safety circuit provides a constant current to the pressure sensor. A microcontroller is coupled to receive the signal from the sensor and is configured to store a first pressure level. The microprocessor compares the first pressure level with the subsequently measured pressure level and generates a control signal if the comparison indicates a change in pressure which exceeds a predetermined amount. The control signal is sent to a spa control circuit. An electronically controlled switch is coupled to receive the control signal from the microcontroller and turn electrical power to the pump off in response thereto.

Abstract: An oil free screw compressor having a low-pressure stage compressor body and a high-pressure stage compressor body. Power of a motor driven by an inverter is transmitted to the compressor bodies through gears. A low-pressure stage blow-off two-way valve is provided in a pipe branching off midway an air pipe connecting between the high-pressure stage compressor body and the low-pressure stage compressor body, and a high-pressure stage blow-off two-way valve is provided in a pipe branching off from a discharge air pipe provided on a discharge side of the high-pressure stage compressor body. During no-load operation, a controller gives a command to the inverter to make the rotational speed of the motor a set lower limit rotational speed, and also gives an open command to the low-pressure stage blow-off two-way valve.

Abstract: A depression container comprises a vessel including a compartment and a cover for enclosing and thus sealing the compartment. An air pump draws air out of the compartment and a pressure-activated switch controls on/off of the air pump. The pressure-activated switch detects an internal pressure in the compartment. The air pump is turned on when the internal pressure is higher than a predetermined first pressure value. The air pump is turned off when the internal pressure is lower than a predetermined second pressure value. In an alternative embodiment, the pressure-activated switch detects a pressure difference resulting from a closing motion of the cover on the vessel and turns the air pump on to thereby draw air out of the compartment of the vessel. The air pump is turned off when an internal pressure in the compartment detected by the pressure-activated switch is lower than a predetermined pressure value.

Abstract: A water pressure system includes a pressure tank installed underground within the well casing of a well. The water pressure system includes a submersible pump connected to the inlet of the pressure tank by a drop pipe. The outlet of the pressure tank is connected to a second drop pipe and in turn to a discharge pipe for distribution of pressurized water to a house or other building. A pressure switch is connected to the pressure tank for controlling the submersible pump. The pressure tank includes an outer sidewall with an inlet end and an outlet end. An expandable diaphragm bladder located within the outer sidewall is connected between the inlet and outlet of the tank. A tube extends through the center of the bladder between an inlet opening and an outlet opening. The tube has a plurality of holes therein to allow water to flow through the tube and into and out of the expandable bladder. Pressurized air fills the empty space between the bladder and the outer sidewall to pressurize the water in the bladder.

Abstract: The present invention provides a compressor that enables the increase of compression efficiency, the prevention of abnormal temperature rising in the discharge, and the reduction of power loss.

Abstract: An air feeding device for endoscope system includes an air compressor that compresses air and feeds the air in a sealed space, and a pressure sensor that detects air pressure in the sealed space. Further, a pressure setting device and a pressure controller are provided. The pressure setting device is used for setting a pressure value to be achieved in the sealed space, and the pressure controller turns ON and OFF the compressor in accordance with the air pressure detected by the pressure sensor and the pressure value set by the pressure setting device. The air feeding device has a main valve. An inlet of the main valve is connected to the sealed space, and an outlet of the main valve is connected to an outlet of the air feeding device. By opening the main valve, the air enclosed in the sealed space is discharged from the outlet to strike an object at a certain pressure.

Abstract: The invention relates to a method for controlling a compressor installation with at least one lubricated screw-type compressor element (1) connected to a pressure vessel (11) which is driven by an electric motor (10) which is regulated in function of the compression pressure, and which compresses the gas supplied through the gas inlet conduit (2). The return flow of lubricating agent through the return conduit (7) also is determined by a controlled valve (9) which is provided with a calibrated opening (29) and which is controlled by control means (43) which, as the number of revolutions of the screw-type compressor element (1) has dropped below a well-defined value, put the controlled valve (9) into the position in which it restricts the return flow of lubricating agent to a flow through the calibrated opening (29).

Abstract: An endoscope air sending device (15) has a compressor (13), an air tank (34), an air filter (35), a pressure control valve (38), a pressure sensor (14), and a discharge valve (12) are provided. The compressor and the air tank are communicated with each other through an air tube (AT5), and the air tank and the air filter are communicated with each other through an air tube (AT4). The air filter and the discharge valve are communicated with each other through an air tube (AT3), and the pressure control valve, the air sensor and the discharge valve are also communicated with one another through the air tube (AT3). By communicating those components with one another in the above-described manner, a closed space is formed.

Abstract: A pump arrangement is disclosed having a housing, a first pumping chamber within the housing, a drive shaft carried by the housing, and first pumping means arranged for rotation within the first pumping chamber. The first pumping means is driven by the drive shaft. A second pumping chamber accommodating a second pumping means is separated from the first pumping chamber by the housing such that the housing forms common separation wall. To provide a compact arrangement in which the first and second pumping chambers are reliably sealed from each other, the second pumping means is driven by the drive shaft via a magnetic coupling. Thus, the coupling comprises a drive rotor connected to the drive shaft and a driven rotor carried by the housing. The driver rotor and the driven rotor are separated by a separation wall assembly serving as a static seal to hermetically seal the second pumping chamber from the drive shaft.

Abstract: A spray controller accepts a spray pressure input and a pressure control input, and provides a pressure control output. The controller includes an amplifier and pressure transducer, and its pressure control output is the product of the amplifier's gain and the sum of (a) a preset calibration voltage and (b) the product of the pressure transducer's gain and electrical response. The pressure control input controls the gain of the transducer to vary the pressure control output.

Abstract: Lift pump guard for a pump operable by an electrical motor. The lift pump guard monitors variable parameters and actuates a relay to electrically terminate operation of the pump motor when the pump is dry running. Also a method of protecting a pump from dry running compares a measured parameter to a predetermined value and terminates operation based on the comparison.

Abstract: A control circuit for use with a spa system includes a pressure sensor which generates a signal representative of the pressure in the system. A microcontroller is coupled to receive the signal from the sensor and is configured to store a first pressure level. The microprocessor compares the first pressure level with the subsequently measured pressure level and generates a control signal if the comparison indicates a change in pressure which exceeds a predetermined amount. An electronically controlled switch is coupled to receive the control signal from the microcontroller and turn electrical power to the pump off in response thereto.

Abstract: A remote pump control apparatus and method that allows a septic tank service worker to physically control the end of the evacuation hose and operate a conventional pump which induces flow therein while servicing a septic tank including an actuator that mounts on and manipulates the flow control of the pump. The compressed fluid-driven actuator is controlled by a hand-held remote signal sender. A septic tank service worker depresses a switch on the hand-held remote signal sender and generates a signal which is received in a control box. The control box activates a solenoid which directs compressed fluid into one passage of a housing of the actuator, causing the actuator to manipulate the pump flow control in one direction, and into another passage, causing the actuator to manipulate the pump flow control in an opposite direction.

Abstract: A device for measuring and automatically controlling the volumetric rate of air through an air handling system used in connection with clean rooms. A desired volumetric air rate is maintained by measuring air pressure differentials between different locations in the system. The volumetric air rate is adjusted by using a variable frequency drive to adjust the speed of the fan in response to a measured pressure differential.

Abstract: When a steplike reference signal is supplied while a switch is open, an offset signal for compensating for the dead time of a pneumatic device is generated by an offset generator and supplied as a manipulated variable for the pneumatic device. When a feedback increases in level and a speed higher than a reference speed is detected by a speed detector, the switch is closed by a switching signal, switching from a PD control mode to a PID control mode. The pneumatic device thus controlled has a reduced response time and can made a quick response.