Alternating Sequences Patents (Class 417/8)
  • Patent number: 11111922
    Abstract: A method of operating a vacuum pump system, the method including the steps of: operating a primary vacuum pump having a variable speed motor; connecting at least two secondary vacuum pumps in parallel with said primary vacuum pump; dividing the secondary vacuum pumps in groups, each group including at least one secondary vacuum pump; and assigning a priority for each of said groups. The method further includes the steps of measuring the inlet pressure p1, comparing the measured inlet pressure p1 with a predetermined pressure value p0, and if p1 is higher than p0, starting the secondary vacuum pump at a first predetermined startup load Sstartup,1 if it includes a fixed speed motor, and/or starting the secondary vacuum pump at a second predetermined startup load Sstartup,2, if it includes a variable speed motor.
    Type: Grant
    Filed: February 13, 2017
    Date of Patent: September 7, 2021
    Assignee: ATLAS COPCO AIRPOWER, NAAMLOZE VENNOOTSCHAP
    Inventor: Joeri Coeckelbergs
  • Patent number: 11041488
    Abstract: System with two pumps (B1, B2) connected in parallel to a delivery manifold and respective electronic pressure switches (P1, P2) provided with a pressure sensor (S1, S2) connected to the delivery manifold and designed to alternate their operation between a first configuration with a first shut-down pressure (Pmax1) and a first start-up pressure (Pmin1) and a second configuration with a second shut-down pressure (Pmax2) and a second start-up pressure (Pmin2), the first shut-down pressure (Pmax1) being greater than the second shut-down pressure (Pmax2) and the first start-up pressure (Pmin1) greater than the second start-up pressure (Pmin2). Each of the pressure switches (P1, P2) is designed to alternate their operation between the two configurations according to a pressure reading (Pimp) at the delivery manifold by the pressure sensor(s) (S1, S2). The invention also relates to a pressure switch.
    Type: Grant
    Filed: October 18, 2017
    Date of Patent: June 22, 2021
    Assignee: COELBO CONTROL SYSTEM, S.L.
    Inventors: Fernando Banus Garcia, Jaume Buch Llorach, Angel Andres Castellano
  • Patent number: 9938968
    Abstract: A cryopump system includes: a plurality of cryopumps; a plurality of compressor units arranged to operate in parallel in accordance with a control output, respectively, to supply refrigerant gas to the plurality of cryopumps; and a cryopump controller operative to determine the control output for each of the plurality of compressor units. The cryopump controller adjusts a preset value for at least one of the compressor units, the preset value being utilized to determine the control output, so that operation statuses of the respective compressor units are substantially equalized.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: April 10, 2018
    Assignee: SUMITOMO HEAVY INDUSTRIES, LTD.
    Inventor: Masamichi Ando
  • Patent number: 9464836
    Abstract: An air conditioner having a plurality of compressors and a starting control method thereof, where the plurality of compressors is simultaneously started if a starting load of the air conditioner is smaller than a reference load, and the plurality of compressors is sequentially started if the starting load of the air conditioner is larger than the reference load, thereby simultaneously starting the plurality of compressors at a starting load section in which a starting stability of the compressors is secured, and thus capable of enhancing the cooling and heating performance.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: October 11, 2016
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Kyoung Rock Kim, Jong Moon Kim, Hyeong Joon Seo, Byoung Guk Lim, Chawang Jang
  • Patent number: 9297245
    Abstract: Disclosed are systems and methods utilizing multiple parallel pumps to deliver a mixture of the proppant and clean fluid via a manifold trailer. One method of providing a step-change in proppant concentration includes selecting a first flow rate for a first pump connected between a first input node and first output node, calculating a first transit time for a flow of a fluid at the first flow rate through a first flow path extending from the first inlet node, through the first pump, and to the first outlet node, and calculating a second flow rate for a second pump connected between the first input node and the first output node such that a second transit time for a flow of the fluid through a second flow path extending from the first inlet node, through the second pump, and to the first outlet node is equal to the first transit time.
    Type: Grant
    Filed: August 15, 2013
    Date of Patent: March 29, 2016
    Assignee: Halliburton Energy Services, Inc.
    Inventors: Stanley V. Stephenson, Wesley J. Warren
  • Patent number: 8777584
    Abstract: An energy saving three pump waste water pump station design that eliminates the high energy usage of traditional waste water pump stations, reduces maintenance costs to the pumps and increases the useful lives of the pumps by having a primary pump running continuously, a second pump mining during high demand periods and a third pump functioning primarily as a back up pump. Unlike conventional pump-station designs, the Energy Saving Green Pump Station Design utilizes a single float switch panel. Whereas independent float switches trigger start-stops in conventional pump station designs, the Green design incorporates a remote controllable panel for rotating the primary, secondary and third pumps on a schedule. This design also provides a process for determining in-flow rates for a pump station and efficiency operating points of pumps so that the most efficient pumps with the lowest horsepower can be selected.
    Type: Grant
    Filed: December 22, 2011
    Date of Patent: July 15, 2014
    Inventor: Nasser Fred Mehr
  • Patent number: 8545189
    Abstract: A method and an arrangement for controlling a pump station includes measurement of the surface level of a liquid (465) by means of a sensor (452) and controlling the electric drive (401, 420, 430) of the pump (440) to a predetermined speed of rotation when a specific surface level value has been reached. This predetermined rotation speed value is preferably the rotation speed at which the ratio of the flow rate to the consumed power, i.e. the efficiency, is optimal. The measurement of the surface level and the related data processing for control of the pump are performed in a frequency converter (420) in conjunction with the control.
    Type: Grant
    Filed: March 15, 2005
    Date of Patent: October 1, 2013
    Assignee: ABB Oy
    Inventors: Srikanth Venkatachari, Mikael Holmberg
  • Patent number: 8521452
    Abstract: A liquid level determination system includes pressure determination components that include an interference dampener to mitigate interference originating from a bubbler air compressor. The system may include a pressure pipe with a pressure sensing pipe end located adjacent to the pressure determination components and a bubbler pipe end locatable at least partially in a wet well. The wet well may include a pump that has a volute. The pressure pipe may further include layered pipe sections, and the position of the bubbler pipe end may be calculated so that it is not lower than a level substantially equivalent to a center line through the volute. The bubbler air compressor may provide air pressure to the pressure pipe.
    Type: Grant
    Filed: November 20, 2012
    Date of Patent: August 27, 2013
    Assignee: Data Flow Systems, Inc.
    Inventors: Thomas F. Smaidris, James Marion Boyd, Darrell Lee Manchester, Gregory Louis Valenti
  • Patent number: 8371821
    Abstract: An electrical control system for energy efficient pump stations providing for continuous operation of a single primary pump with a second pump functioning as the support pump and a third pump acting as the standby/emergency pump. All pumps are of equal horsepower and horsepower selection is determined by the system curve to select the lowest, most efficient horsepower necessary to discharge water at the highest inflow rate while not allowing the water level to drop below the submerged pump level during continuous running of the primary pump. A timer having an indicator arm rotates one full revolution every thirty days changing the pump sequence to reduce wear and tear on individual pumps. Each pump functions as the primary, secondary and backup/emergency pump for the same number of hours during the monthly cycle. Adding control circuits enables one or more pumps to be added when necessary.
    Type: Grant
    Filed: August 17, 2012
    Date of Patent: February 12, 2013
    Inventor: Nasser Fred Mehr
  • Patent number: 8340929
    Abstract: A liquid level determination system to determine the level of a liquid in a wet we is disclosed. The system may include pressure determination components and a pressure pipe with a pressure sensing pipe end located adjacent to the pressure determination components and a bubbler pipe end locatable at least partially in the wet well. A transducer is used to determine a pressure level within the pressure pipe maintained by a bubbler air compressor. A level detection processor may analyze the pressure level to determine a liquid level in the wet well. An interference dampener is included to mitigate interference originating from the bubbler air compressor. The interference dampener may be provided by transducer plug to restrict air flow. Alternatively, the interference dampener may be provided by a computer operated program to monitor and mitigate the interference.
    Type: Grant
    Filed: February 6, 2012
    Date of Patent: December 25, 2012
    Assignee: Data Flow Systems, Inc.
    Inventors: Thomas F. Smaidris, James Marion Boyd, Darrell Lee Manchester, Gregory Louis Valenti
  • Patent number: 8235674
    Abstract: A paint circulation pump control system having a plurality of pneumatic or hydraulic pump assemblies that operate at different outputs in response to load changes on a paint application system is provided. Each pump assembly includes a first regulator and second regulator having different pressure output settings selectively connecting a compressed air source with a pump. A control valve in each pump assembly is responsive to a single switch to connect the compressed air source to the pumps via the first or second regulators. When the switch directs a change, all of the pump assemblies simultaneously change the regulator that is connecting the pump with the compressed air source.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: August 7, 2012
    Assignee: Honda Motor Co., Ltd.
    Inventors: Shubho Bhattacharya, Sarah Crush
  • Patent number: 8083493
    Abstract: For water-jet surgery pump devices are known by means of which a sterile fluid is transported through a reservoir to the surgical instrument by means of piston pumps or similar volumetrically transporting pumps. In accordance with the present invention it is proposed either to construct drive means for the pumps in such a way that their suction cycle is shorter than the output cycle, or to provide a pump with at least three pump chambers and to construct the drive means in such a way that the suction and output cycles of the pump chambers overlap one another.
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: December 27, 2011
    Assignee: ERBE Elektromedizin GmbH
    Inventors: Martin Hagg, Ralf Kuhner
  • Patent number: 7854142
    Abstract: An air conditioner having two compressors enables, when one compressor is started, the phase advance capacitor for the other compressor to be temporarily separated and used in parallel with the phase advance capacitor for the one compressor. These compressors can have an increased starting torque without using a starting capacitor.
    Type: Grant
    Filed: May 2, 2007
    Date of Patent: December 21, 2010
    Assignee: Panasonic Corporation
    Inventors: Koji Hatano, Hideyuki Kanzaki, Yoshihito Yamada
  • Publication number: 20080131258
    Abstract: In a method for controlling a compression installation (1), the installation has at least two compressor units (i=1, , N) that can be separately turned on or off, a plurality of devices for modifying the output of the compressor units and a control device (10). Known methods and devices do not function optimally in terms of the power consumption of the entire compression installation. The power consumption (EG) for the operation of a plurality of compressor units (i=1, , N) of a compression installation (1) can be optimized by calculating a novel circuit configuration (Si, t) and automatically adjusting the novel circuit configuration (Si, t) by a control device (10).
    Type: Application
    Filed: February 2, 2006
    Publication date: June 5, 2008
    Inventors: Helmut Liepold, Michael Metzger
  • Patent number: 6419454
    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.
    Type: Grant
    Filed: June 14, 2000
    Date of Patent: July 16, 2002
    Inventor: Leo P. Christiansen
  • Patent number: 6186743
    Abstract: A sequential controller is provided for sequencing multiple electric loads such electric pumps. That is, for each cycle the next load is designated as the lead load in a round-robin fashion. The controller uses cost effective electro-mechanical relay logic an thus avoids conventional solid state technology. In order to sequence the loads on each successive cycle, the electro-mechanical relay connected to the sensors comprises a double-throw contact set. The double-throw contact set comprises two complementary contacts, both of which alternate between normally open and normally closed on each successive cycle. In this manner one each successive cycle, the pumps designated as the lead pump and the lag pump automatically alternate in a round-robin fashion. Further, when the lead pump is disabled the lag pump is immediately actuated without disruption of service.
    Type: Grant
    Filed: November 4, 1999
    Date of Patent: February 13, 2001
    Assignee: American Manufacturing Co., Inc.
    Inventor: Kevin J. Romer
  • Patent number: 6142740
    Abstract: A compression system includes a sequencing switch movable between a first switch position and a second switch position for alternating a first compressor and a second compressor between a lead mode and a lag mode so that one of the compressors is always in the lead mode and one of the compressors is always in the lag mode. The compression system includes a first compressor including a first microcontroller having a data entry device for establishing a lead mode pressure range and a lag mode pressure range. The first compressor includes a first pressure gauge for sensing the pressure level of compressed fluid discharged therefrom and for relaying the sensed pressure level to the first microcontroller. The first microcontroller continuously monitors the pressure level of the compressed fluid discharged from the first compressor and compares the pressure level of the compressed fluid to the lead mode pressure range and the lag mode pressure range.
    Type: Grant
    Filed: November 25, 1998
    Date of Patent: November 7, 2000
    Assignee: Ingersoll-Rand Company
    Inventor: Marty L. Connell
  • Patent number: 5811669
    Abstract: A computational sequence that allows a stand-alone instrument or a central data processing unit to calculate flow of compressed ideal gases based on measurements of pressure and time only, in systems where compressors start and stop at regular intervals and based on the system's pressure.
    Type: Grant
    Filed: February 20, 1997
    Date of Patent: September 22, 1998
    Assignee: Rodolfo Esteban Polonyi
    Inventor: Michael J. G. Polonyi
  • Patent number: 5449274
    Abstract: An electronic pump selector system uses a programmable processor to select one of a plurality of pumps to be energized in response to an appropriate feedback signal from the selected pump. A current limited feedback circuit is incorporated which provides a varying voltage in response to a level switch associated with a selected pump indicating a high fluid level. In response to the voltage feedback signal, the selected pump is energized for a predetermined period of time. Subsequently, another pump is selected. The next selected pump is energized also for a predetermined period of time in response to a varying voltage feedback signal therefrom. The next pump is then selected and the sequence continued.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: September 12, 1995
    Assignee: Metropolitan Pump Company
    Inventor: John Kochan, Jr.
  • Patent number: 5417649
    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.
    Type: Grant
    Filed: June 1, 1993
    Date of Patent: May 23, 1995
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masafumi Kawahara, Akihiro Maeda
  • Patent number: 5343384
    Abstract: Load sharing is achieved in a multiple compressor system by a program in a computer which sends signals to, and receives data from, a microcontroller located at each compressor. One compressor, designated as the lead compressor, furnishes its operating parameters, via the computer, to all the other, lag, compressors. The operating parameters include inlet valve position and bypass valve position of each compressor and the microcontroller controls the actuatation of both valves. When system demand decreases, compressors are gradually unloaded, and then stopped to go off-line. When system demands increase, compressors are first started, and then gradually loaded before going on-line. Compressors go both on-line and off-line subject to certain time delays so that compressors are gradually added to, or shed from, the load. To equalize running time, all compressors in the system may undergo a periodic rotation and compressors go off-line in reverse order that they came on-line.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: August 30, 1994
    Assignee: Ingersoll-Rand Company
    Inventors: Alvin J. Fisher, Troy S. Smoot, Daniel E. Kincer
  • Patent number: 5309727
    Abstract: System and process are disclosed for reacting to conditions that may arise in a plurality of discrete chiller units all individually controlled by dedicated control units. The system and process react to temperature conditions of the coolant when it enters and when it leaves the chiller units. The system normally supervises the manner in which the chillers are allowed to individually increase or decrease chilling capacity. The system furthermore overrides this supervisory control of the individual chiller units when the coolant entering the chiller units drops below a threshold value. The chilling capacity of all running chiller units is decreased when this latter condition occurs.
    Type: Grant
    Filed: May 7, 1993
    Date of Patent: May 10, 1994
    Assignee: Carrier Corporation
    Inventors: Paul J. Duff, Keith G. Michaelsen
  • Patent number: 5231846
    Abstract: A method of staging and modulating compressors in a multi-circuited refrigeration system including a plurality of condensing heat exchange circuits where each condensing heat exchange circuit includes a plurality of compressors. The method comprises the steps of: accumulating a first operative condition for each compressor; accumulating a second operative condition for each compressor; determining the status of each compressor in each circuit and designating therefrom a first list of circuits having compressors available to be turned on and a second list of circuits having compressors available to be turned off.
    Type: Grant
    Filed: January 26, 1993
    Date of Patent: August 3, 1993
    Assignee: American Standard Inc.
    Inventors: Craig M. Goshaw, Robert L. Oltman
  • Patent number: 5211031
    Abstract: A scroll type compressor having a pair of scroll type compression units which are encased in the same casing so as to make a common use of a lubricating oil reservoir provided in the casing, wherein the compression units have compression elements, drive shafts, driving motors and other components which are of the same constructions and specifications, and wherein each of the compression units are adapted to be driven selectively by commercial electrical power or through a frequency-variable inverter so as to operate at different speeds. Since both compression units can be made up from the same components such as the compression elements, loads in the production, service and administration, are greatly reduced contributing to a reduction in the labor and cost, while eliminating any mounting error.
    Type: Grant
    Filed: May 22, 1991
    Date of Patent: May 18, 1993
    Assignee: Hitachi, Ltd.
    Inventors: Akira Murayama, Tadashi Fukuishi, Sigeaki Kuroda, Toshiaki Koyama, Tadao Ochiai, Toshio Hirai, Shintaro Sado, Yasushi Izunaga, Shouji Kikuchi, Fumio Yoshinaga
  • Patent number: 5123256
    Abstract: A method of staging a plurality of compressors in a refrigeration system. The method comprises the steps of: accumulating a first operative condition for each compressor; accumulating a second operative condition for each compressor; initiating operation of whichever compressor has the lowest accumulation of the first operative condition whenever a system controller calls for an increase in system capacity; and terminating operation of whichever compressor has the greatest accumulation of the second operative condition whenever the system controller calls for a reduction in system capacity.
    Type: Grant
    Filed: May 7, 1991
    Date of Patent: June 23, 1992
    Assignee: American Standard Inc.
    Inventor: Robert L. Oltman
  • Patent number: 4941596
    Abstract: Mixing concentrates requires the precise dispensing of predetermined amounts of concentrate into predetermined amounts of liquid and such mixes can be obtained by the use of a system having two positive displacement pumps, one for pumping larger volumes with each operation than the second pump and a pressure regulator to maintain a predetermined pressure on the solvent carrier fluid for the mixture.
    Type: Grant
    Filed: July 14, 1986
    Date of Patent: July 17, 1990
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: John L. Marty, Philip S. Plumbo
  • Patent number: 4580947
    Abstract: Disclosed is a method of controlling the operation of a plurality of compressors each having at least one capacity controller capable of changing the discharge rate of the compressor in a stepped manner in such a manner as to provide a total discharge rate just meeting the load demand which varies momentarily. In this method, the control system is divided into a capacity control loop for responding to comparatively small load variance and a compressor control loop for responding to a comparatively large load variance. The capacity control loop is further divided into a sub-loop for capacity controllers of a compressor which has worked longest and which is to be stopped first and a sub-loop for the capacity controllers of other compressors. The unloading operation is commenced preferentially with the sub-loop for the capacity controllers of the compressor to be stopped first, while the on-loading operation is made first with the sub-loop for the capacity controllers of other compressors.
    Type: Grant
    Filed: January 4, 1985
    Date of Patent: April 8, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Yozo Shibata, Mitsuji Konishi
  • Patent number: 4551068
    Abstract: A 100% solid state, liquid level control circuit which utilizes printed board construction with integrated circuits to control duplex pumps. Mercury switches provide information to the solid state, non-inductive input interface circuitry which relays this information to logic control circuitry and an alternator. The logic control circuitry and an alternator forward the information to solid state, non-inductive output circuitry for powering pump starters. The alternator selectively alternates the sequencing of the pumps for controlling the lead pump. Current limiting devices, light emitting diodes and logic control circuitry are combined to provide operation of pump starters for controlling the liquid level in a wet well, reservoir, bilge of a vessel, or the like.
    Type: Grant
    Filed: July 25, 1983
    Date of Patent: November 5, 1985
    Inventor: Ronald J. Boudreaux
  • Patent number: 4537047
    Abstract: A transport refrigeration unit of the type which has a single or common refrigerant circuit, and a truck engine driven compressor 22 and a mutually, exclusively operable standby compressor 34 is provided with an arrangement of suction line fitting 46 with a pair of check valves 64 and 66 located physically above the fitting which receives the suction side refrigerant through line 48 from below the fitting and is provided with an inversely related pressure side fitting 54 with associated check valves 68 and 70 and the compressors are of substantially identical pumping capacity and oil capacity, all to the end of preventing an interchange of oil between the compressors during operation, and to migration of refrigerant and oil during periods of inoperation.
    Type: Grant
    Filed: March 2, 1984
    Date of Patent: August 27, 1985
    Assignee: Thermo King Corporation
    Inventors: Jayaram Seshadri, Daniel T. Neimy
  • Patent number: 4502842
    Abstract: The multiple compressor controller and method accomplishes the control of a plurality of variable sized compressors in a multiple compressor distribution system to maintain system pressure at a desired level while maximizing compressor operating efficiency. Control data for use in determining system volume and leakage and various individual compressor parameters is obtained by using the system compressors in a calibration mode and monitoring the effect of each compressor on the system. Once such data is obtained and stored, a plurality of system operating pressures can be preset into a time clock controlled controller, and the controller will automatically maintain these pressures over the time periods indicated by efficiently selecting one or more compressors with the output capacity necessary to match any variation in system demand.
    Type: Grant
    Filed: February 2, 1983
    Date of Patent: March 5, 1985
    Assignee: Colt Industries Operating Corp.
    Inventors: Stephen M. Currier, Bert G. H. Penhollow, Gordon G. Hof, Norbert L. Mast
  • Patent number: 4444545
    Abstract: This is a digital solid state control system for pumping liquid to regulate the condition of the liquid in a container, such as the liquid level. One pump is turned on when the liquid rises to one level, and another pump is turned on when the liquid rises to a higher level. An alarm is activated if the liquid rises to a still higher level or if a leak occurs in either pump. The control system alternates which pump turns on first in successive operating cycles. If a power failure occurs while both pumps are on, when power is restored only one pump comes on immediately; the other comes on only after a time delay.
    Type: Grant
    Filed: April 8, 1982
    Date of Patent: April 24, 1984
    Inventors: David F. Sanders, James R. Aspinwall, Garry A. Armbruster
  • Patent number: 4437811
    Abstract: A submersible pump adapted to pump out the liquid in a reservoir has a built-in control unit for alternate pump operation. The control unit includes step memory means which provides a signal to permit the starting of pump operation every other time a high liquid level sensor senses the liquid. Once started, the pump continues its operation until the liquid level drops below a low liquid level sensor. The submersible pump can be combined with an additional pump having a conventional control unit in which case the two pumps are alternately operated.
    Type: Grant
    Filed: June 30, 1980
    Date of Patent: March 20, 1984
    Assignees: Ebara Corporation, Ebara Densan, Ltd.
    Inventors: Minoru Iwata, Yukio Murata, Tomoyuki Shibata
  • Patent number: 4341983
    Abstract: An automatic system for controlling a plurality of motors includes motor starting circuitry and motor stopping circuitry that serves to sequentially start and stop the motors in the same cyclic order. The starting circuitry has a sensing component for sensing the presence and absence of a condition that reflects the need for starting the motor and a master starting control component which develops two different states that are used in controlling the circuits of the starting circuitry. The control circuits include a plurality of motor starting circuits for starting the respective motors and a plurality of conditioning circuits that normally respond to one of the developed states for conditioning the starting circuits for response sequentially to the other of the developed states and in a cyclic order for starting the motors.
    Type: Grant
    Filed: July 11, 1980
    Date of Patent: July 27, 1982
    Inventor: Mayo Gottliebson
  • Patent number: 4341504
    Abstract: A bubbler tube is used to sense the liquid level in a wet well. Controls provide a constant flow of air, approximately 11/2 to 1 cubic foot per hour, through the bubbler tube which extends to about 6 inches above the top of the pump suction pipe. The pressure in the pipe is proportional to the height of the liquid above the bottom of the bubbler pipe. A transducer connected in the bubbler system responds to pressure changes in the pipe which are transformed to electrical signals used to control the speed of the pump driving motor. The motor will always drive the pump at a speed which corresponds to the flow coming into the wet well.
    Type: Grant
    Filed: December 6, 1979
    Date of Patent: July 27, 1982
    Inventors: Frank A. Hignutt, Robert F. Hignutt, Kenneth W. Hignutt
  • Patent number: 4297081
    Abstract: A pump control system using a purge bubbler, a flat plate manometer having level sensing contacts therein, and control relays and alarms. The flat plate manometer includes a rectangular mercury column having calibration scales and a number of stainless steel contacts disposed along the column. The mercury closes a circuit between a common contact and the column contacts as the mercury rises. The manometer is fabricated from acrylic plastic to provide a light weight, low cost device. The input and output ports include microporous filters to prevent accidental loss of mercury. The input port is connected to a bubbler air pump and a standpipe in the vessel to be controlled. Pump start relays are connected to selected contacts of the manometer column to operate in accordance with the hydrostatic level of the liquid in the vessel. Interlocking relays are used in cooperation with the pump relays to allow pump start and pump stop levels to be independently selected.
    Type: Grant
    Filed: November 5, 1979
    Date of Patent: October 27, 1981
    Inventor: William A. Irvin
  • Patent number: 4179242
    Abstract: A method and an apparatus for liquid supply use a pressure tank and a plurality of pumps. When the pressure or liquid quantity in the pressure tank has decreased below a predetermined level, a preceding or regular pump starts. When the demand is too large for this pump, another pump in standby position starts, too. The regular pump continues running for a predetermined period of time after the start, even if the pressure or liquid quantity in the pressure tank has returned to a predetermined level, whereas the standby comes to a stop upon such recovery. In this manner the frequency of starting the pumps is minimized so as to avoid overheating of pump-driving motors and reduce the power consumption.
    Type: Grant
    Filed: April 26, 1978
    Date of Patent: December 18, 1979
    Assignee: Hitachi, Ltd.
    Inventors: Tadao Tateshita, Yasuhiro Mita, Junichi Nakayama, Koichi Sato