Lubricant Condition Responsive Patents (Class 417/281)
  • Patent number: 11236740
    Abstract: Sealed container (102) houses electric unit (110) equipped with stator (114) and a rotor (116), and compression unit (112) disposed above electric unit (110). Compression unit (112) includes shaft (118) that includes main shaft portion (120) and eccentric shaft portion (122), and cylinder block (124). Compression unit (112) further includes connection portion (136) that connects piston (128) reciprocatively inserted into cylinder (130) and eccentric shaft portion (122), and a thrust bearing that supports a load of shaft (118) in a vertical direction. The thrust bearing includes an upper race in contact with a flange portion of shaft (118), a lower race in contact with a thrust surface of cylinder block (124), and a rolling element. An overall height of sealed container (102) is sized not to exceed a length six times larger than a diameter of piston (128).
    Type: Grant
    Filed: August 27, 2014
    Date of Patent: February 1, 2022
    Assignee: PANASONIC APPLIANCES REFRIGERATION DEVICES SINGAPORE
    Inventors: Ko Inagaki, Masanori Kobayashi, Hiroyuki Kawano
  • Patent number: 11131396
    Abstract: An inlet valve containing a housing with an entry and an exit and an internal part which together with an external part delimits a flow channel between entry and exit, whereby this flow channel is closable by a valve. The valve includes a piston and a valve member. The piston slides in the housing and is connected with the exit and the valve member is formed by a valve shaft piston which slides in the piston such that in rest mode the valve member is pushed by the piston against valve seat. Between the valve shaft piston and the piston a chamber is enclosed which comes into fluid connection with the pressure vessel and has a blow-off exit forming a fluid connection between the chamber and the entry, whereby the valve shaft piston contains a bypass channel connected with the chamber and the sidewall of the valve shaft piston.
    Type: Grant
    Filed: June 4, 2018
    Date of Patent: September 28, 2021
    Assignee: ATLAS COPCO AIRPOWER, NAAMLOZE VENNOOTSCHAP
    Inventor: Joris Mertens
  • Patent number: 11111913
    Abstract: An oil lubricated compressor having a universal motor, efficient starting and re-starting characteristics, and a long operating life. The oil lubricated compressor can have a brushed or brushless universal motor which can drive a cooling fan and a pump. The universal motor can achieve a high torque to voltage ratio, as well as a high torque to current ratio, upon starting or re-starting of the compressor. Optionally, the oil lubricated compressor can use a single cooling fan disposed in the compressor at a location which is between the universal motor and a cylinder head of the pump.
    Type: Grant
    Filed: October 6, 2016
    Date of Patent: September 7, 2021
    Assignee: Black & Decker Inc.
    Inventors: Stephen J. Vos, Lance S. Hathcock, James Vintzel, Dalton E. McFarland
  • Patent number: 11066967
    Abstract: An adjustable lubrication oil conveying system for a combustion engine is proposed which comprises a screw pump for conveying lubrication oil with at least one screw rotatably accommodated in a screw chamber, wherein the screw pump is arranged such that a suction side of the screw chamber is connected with an intake path from an oil sump of the combustion engine, and a pressure side of the screw chamber is connected with a feed path to moving parts of the combustion engine. The lubrication oil conveying system is characterised in particular in that the screw pump is driven by the combustion engine; and towards the suction side of the screw chamber, an adjustable throttle valve is provided by means of which a flow cross-section of the intake path is gradually limitable between an opened position and a closed position. Therefore, the oil pressure in a combustion engine is, for the first time, adjusted by suction throttling in connection with a screw pump.
    Type: Grant
    Filed: April 23, 2019
    Date of Patent: July 20, 2021
    Assignee: NIDEC GPM GMBH
    Inventor: Franz Pawellek
  • Patent number: 10612536
    Abstract: Various assemblies that can be used in a mud pump with a plunger-style piston to reduce seal failures, to offer control in variability of the circumference of the piston to thereby control fluid pressure, and to provide visibility into seal condition during operation. In one embodiment, a sleeve that can vary the overall effective circumference of the piston enables fluid pressure control. In some embodiments, seal failure within a pump can be monitored via a drain port that would receive drilling fluid leaking past a seal during operation of the pump. A discharge valve can be provided between an inlet and an outlet of the mud pump to reduce the load on pump components during start-up. Additional systems, devices, and methods are also disclosed.
    Type: Grant
    Filed: August 3, 2016
    Date of Patent: April 7, 2020
    Assignee: CAMERON INTERNATIONAL CORPORATION
    Inventors: Pascal Berthaud, Robert Berthaud
  • Patent number: 10012247
    Abstract: A variable booster device of a pneumatic regenerative system of a motorized vehicle is in fluid communication with a pneumatic device of the system. The variable booster device includes a main body and a plate slidingly coupled to the main body. The main body includes an inlet, an outlet, and an interior cavity. The plate is reconfigurable between a first configuration, where the outlet is a first size, and a second configuration, where the outlet is a second size. The variable booster device pressurizes the air a first amount when the plate is in the first configuration and pressurizes the air a second amount when the plate is in the second configuration, where the second amount is greater than the first amount. Disposed within the interior cavity is a first helical screw rotor and a second helical screw rotor. The two helical screw rotors are intermeshed with one another.
    Type: Grant
    Filed: December 2, 2016
    Date of Patent: July 3, 2018
    Assignee: Harris Corporation
    Inventors: Steven D. Kay, Jeffrey S. Shapiro, Robert E. Hammerquist, Steven A. Hartney
  • Patent number: 9422928
    Abstract: A compressor assembly (10) configured to increase pressure of a fluid. The compressor assembly includes a cylinder (12a, 12b) forming a space for compressing the fluid and a piston (14a, 14b) configured to reciprocate in the cylinder to compress the fluid. The compressor assembly includes a crank shaft (72) configured to drive the piston and a crank shaft housing (18a, 18b) operatively connected to the cylinder and configured to house the crank shaft. A motor (20) is connected to the crank shaft and drives the crank shaft. The compressor assembly further includes a motor housing (22) connected to the crank shaft housing and configured to house the motor. A thermal insulator (24a, 24b) is disposed between the motor housing and the crank shaft housing to enhance thermal insulation between the motor housing and the crank shaft housing.
    Type: Grant
    Filed: August 22, 2011
    Date of Patent: August 23, 2016
    Assignee: KONINKLIJKE PHILIPS N.V.
    Inventor: Varaprasad Ventrapragada
  • Patent number: 9404494
    Abstract: A screw pump includes a pump housing on which a flange section for installing the pump is formed. The screw pump further includes an integrated pressure limiting valve. The pressure limiting valve in the flange section of the pump housing is installed in the pump housing.
    Type: Grant
    Filed: September 15, 2010
    Date of Patent: August 2, 2016
    Assignee: Robert Bosch GmbH
    Inventor: Walter Joistgen
  • Patent number: 9206805
    Abstract: An air regulator for compressor, in particular for a screw compressor, of the type that has an oil separator device comprising a pre-separator, is provided in a regulator housing containing a valve element which is spring-loaded on one side and can be actuated by means of a piston arrangement. A control device is operatively connected to the air regulator and includes a control piston which, depending on the pre-separator pressure, actuates the valve element of the air regulator in co-operation with a pre-control device in such a way that the regulator immediately and forcibly assumes the closed position upon starting the compressor, while the regulator assumes the open position in an unloaded initial state.
    Type: Grant
    Filed: March 30, 2012
    Date of Patent: December 8, 2015
    Assignee: Rotorcomp Verdichter GmbH
    Inventor: Enrico Stephan
  • Patent number: 8959920
    Abstract: An assembly or system is provided for selectively regulating journal bearing lubrication between at least first and second levels in an aircraft engine. A high pressure pump includes movable portions at least in part supported by a journal bearing. A selector valve is configured to selectively supply lubrication flow to the journal bearing. In addition, a relief valve is configured to receive a signal from the selector valve defining a pressure level at which the relief valve should relieve pressure.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: February 24, 2015
    Assignee: Eaton Corporation
    Inventor: Martin A. Clements
  • Patent number: 8911217
    Abstract: An abnormality detecting device for a hydraulic system is disclosed. The hydraulic system has a pressure level switching mechanism that adjusts oil pressure in accordance with the operating state of an internal combustion engine. The device includes an oil pressure sensor and a ECU. The oil pressure sensor detects an oil pressure that is adjusted by the pressure level switching mechanism. When the pressure level switching mechanism changes the oil pressure from a first oil pressure level to a second oil pressure level, which is higher than the first oil pressure level, the ECU compares the oil pressure detected by the oil pressure sensor with a determination oil pressure level, which is lower than and close to the second oil pressure level. The ECU determines that there is an abnormality in the hydraulic system if the oil pressure detected by the oil pressure sensor does not change to pass the determination oil pressure level.
    Type: Grant
    Filed: December 2, 2009
    Date of Patent: December 16, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Katsuaki Takahashi
  • Publication number: 20140219821
    Abstract: A continuous run controller for a dual control compressor system includes an integrated housing containing a pilot valve and a hydraulic unloader valve. Low pressure in the hydraulic oil system opens the hydraulic unloader valve such that the suction valve unloader assembly unloads the compressor. High pressure in an air receiver of the compressor system opens the pilot valve such that the suction valve unloader assembly unloads the compressor.
    Type: Application
    Filed: January 2, 2014
    Publication date: August 7, 2014
    Inventors: Tingrong Ren, Keith Stephens, Gary Hyer
  • Patent number: 8532887
    Abstract: A switching apparatus is provided in a hydraulic control apparatus having a fluid transmission apparatus; a lockup clutch; a switching valve that controls engagement of the lockup clutch; and a control oil pressure generation apparatus that pressurizes oil and outputs a control oil pressure to control activation of the switching valve. The switching apparatus executes a control to warm the oil input into the control oil pressure generation apparatus if the temperature of the oil is below a predetermined temperature and prohibits execution of the control to warm the oil input into the control oil pressure generation apparatus if the temperature of the oil equals or exceeds the predetermined temperature.
    Type: Grant
    Filed: April 14, 2009
    Date of Patent: September 10, 2013
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Shuji Moriyama, Akira Murakami, Keisuke Ichige, Hiroyuki Nishizawa, Masanori Iritani, Hideyuki Suzuki
  • Patent number: 8459392
    Abstract: A snowmobile (10) having an electronic oil pump (72) fluidly connected to an oil tank (70) thereof is disclosed. The electronic oil pump (72) is fluidly connected to an engine (24) of the snowmobile (10) for delivering lubricant to the engine (24). An electronic control unit (150) is electrically connected to the electronic oil pump (72) for controlling actuation of the electronic oil pump (72). A method of operating an electronic oil pump (72) is also disclosed.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: June 11, 2013
    Assignee: Bombardier Recreational Products Inc.
    Inventors: Michel Bernier, Bruno Schuehmacher
  • Patent number: 8123499
    Abstract: A compressor assembly includes a support plate and a plurality of components mounted on the support plate via mechanical connections. The plurality of components includes at least a drive and a compressor for compressing air, the compressor being driven by the drive. The assembly also includes at least one line integrated into the support plate and selected ones of the mechanical connections. The line provides at least one of a fluidic connection and an electrical connection between at least two of the plurality of components.
    Type: Grant
    Filed: March 8, 2007
    Date of Patent: February 28, 2012
    Assignee: Knorr-Bremse Systeme fur Schienenfahrzeuge GmbH
    Inventors: Englebert Koeck, Juergen Mendel
  • Patent number: 8046126
    Abstract: The start control is repeatedly performed for an oil pump that pressure feeds the flow of oil in a motor cooling system. This control is repeated for every specified rise in motor temperature (e.g., every 10° C.) from an initial starting temperature. This arrangement increases the potential for a successful start-up of the oil pump even when the oil has a high viscosity due to a relatively low outside air temperature. In the event of a failed start-up of the oil pump by repeated starting, the start control determines an abnormality exists in the oil pump or its power supply if an outside air temperature is greater than a reference temperature. This arrangement effectively eliminates incorrect detection of an abnormality in the oil pump or its power supply.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: October 25, 2011
    Assignees: Toyota Jidosha Kabushiki Kaisha, Aisin Aw Co., Ltd.
    Inventors: Eiji Yanagida, Tetsuhiro Tsuchie
  • Patent number: 7854601
    Abstract: A lubricant-tight vane rotary vacuum pump includes at least one pump stage (17, 18) having a safety valve (3) for controlling gas flow to the pump stage, a lubricant pump, a lubricant reservoir (30) at least partially surrounding the pump stage housing (10, 40), and a hydraulic conduit (31) connecting the lubricant pump outlet (22) with the safety valve (3), with a pressurized lubricant flow through the hydraulic conduit (31) opening the safety valve (3), and a channel (32) branching from the hydraulic conduit (31) for delivering a pressurized lubricant into the lubricant reservoir (30).
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: December 21, 2010
    Assignee: Pfeiffer Vacuum GmbH
    Inventor: Juergen Wagner
  • Patent number: 6886354
    Abstract: Two liquid levels are sensed in the oil sump of a compressor to determine if sufficient oil and excess refrigerant are present prior to starting the compressor and appropriate steps taken, if necessary. At start-up, and during operation, the presence or flow of liquid refrigerant in the suction of the compressor is sensed and appropriate steps taken, if necessary.
    Type: Grant
    Filed: April 4, 2003
    Date of Patent: May 3, 2005
    Assignee: Carrier Corporation
    Inventor: Kevin F. Dudley
  • Patent number: 6682322
    Abstract: In an electromotive compressor of an air-conditioner for use in an automobile, an interior space of a container of a compressor is divided into a space including a compression mechanism portion and an electric motor portion, and an oil storage space, wherein an oil passage is provided in a lower portion while a partition having a gas passage in an upper portion thereof, and a gas emission pipe is provided in one of the two (2) spaces at the oil storage portion side, being divided by the partition plate, while an oil supply pipe in the other, thereby making an opening of the oil supply pipe dipped within the lubricating oil even when a car declines.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: January 27, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Sunao Funakoshi, Hidenori Yokoyama, Masao Imanari, Masatsugu Chikano
  • Patent number: 6575708
    Abstract: A head assembly for use in a compressor having a first compression chamber for compressing a fluid includes a manifold housing defining an intake port, an exhaust port and a control valve port and having an outer wall, a first inner wall and a second inner wall. The outer wall and the first inner wall define a suction chamber and the first inner wall and the second inner wall define a discharge chamber. An aperture is formed in the first inner wall for guiding the fluid and oil from the discharge chamber to the control valve port. The second inner wall is internal to the outer wall and the first inner wall and defines an exit chamber. The exit chamber is in fluid communication with the exhaust port and the second inner wall defines a partition between the aperture and the exhaust port such that the oil pools in the discharge chamber.
    Type: Grant
    Filed: September 13, 2001
    Date of Patent: June 10, 2003
    Assignee: Delphi Technologies, Inc.
    Inventor: Bradley J. DeWispelaere
  • Patent number: 6431843
    Abstract: A method of ensuring adequate oil thickness for the bearings in a sealed compressor includes the step of monitoring the viscosity of a lubricant for the bearings. If the monitored viscosity drops below a minimum, then some control is effected to reduce the necessary bearing film thickness. In a preferred embodiment, an unloader valve is opened to reduce the load on the bearings.
    Type: Grant
    Filed: December 15, 2000
    Date of Patent: August 13, 2002
    Assignee: Carrier Corporation
    Inventor: Kevin F. Dudley
  • Publication number: 20020102163
    Abstract: A method of ensuring adequate oil thickness for the bearings in a sealed compressor includes the step of monitoring the viscosity of a lubricant for the bearings. If the monitored viscosity drops below a minimum, then some control is effected to reduce the necessary bearing film thickness. In a preferred embodiment, an unloader valve is opened to reduce the load on the bearings.
    Type: Application
    Filed: December 15, 2000
    Publication date: August 1, 2002
    Applicant: Carrier Corporation
    Inventor: Kevin F. Dudley
  • Patent number: 6302654
    Abstract: A compressor protection and control subsystem for a rotary compressor provides temperature pressure, mis-wiring and vibrational protection for the scroll machine. The vibrational protection comprises a vibration sensor which is integrated on the circuit board of the protection and control subsystem. The vibration sensor, in conjunction with at least one timer, monitors the vibrations of the scroll machine and will shut down the machine when excess vibrations are sensed over a prespecified period of time. The temperature system monitors operating temperature conditions the pressure system monitors operating pressures and the mis-wiring system monitors the power supplied to the compressor. Once an undesirable characteristic is identified, the operation of the scroll machine is stopped. These protection systems are integrated into a single subsystem which identifies the reason of shutting off the scroll machine in order to simplify repairs needed.
    Type: Grant
    Filed: February 29, 2000
    Date of Patent: October 16, 2001
    Assignee: Copeland Corporation
    Inventors: Hank E. Millet, Natarajan Rajendran, William W. McCroskey
  • Patent number: 5871338
    Abstract: The invention pertains to a vacuum pump (1) with a closable line (63, 102) through which gas ballast can be fed into the pump chamber (8, 9); to eliminate the danger that a recipient hooked up to the vacuum pump may be charged with air in the event of a pump failure, the invention proposes that the line be equipped with a control valve (59, 60, 61; 98, 99; 109, 110) to regulate the gas ballast feed as a function of operating conditions, such that the line is closed in the event of a pump failure.
    Type: Grant
    Filed: January 29, 1996
    Date of Patent: February 16, 1999
    Assignee: Leybold Aktiengesellschaft
    Inventors: Thomas Abelen, Lutz Arndt, Peter Muller
  • Patent number: 5236313
    Abstract: An improved rotary-type vacuum pump includes a lubrication circuit in which an oil inlet port of an oil suction duct is directed towards the floor of the pump casing, rotors having oil spaces filled with oil between the vanes, an oil filter provided at the outside of the pump housing, and an excess pressure discharge valve immersed in the oil and being disposed at a terminating portion of the lubrication circuit. The mounting of other essential elements of the pump unit is concentrated on the front cover and the pump housing of the pump.
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: August 17, 1993
    Inventor: Young-Soo Kim
  • Patent number: 5215444
    Abstract: A system for and a method of establishing and maintaining fluid at desired cleanliness, viscosity and temperature levels in a flow system. The system includes a driven pump that circulates fluid from a fluid source through a hydraulic loading system that includes an unloading valve. As fluid flows through the valve, a pressure drop is created across the valve operator, which restricts flow through the valve. This pressure drop across the valve operator results in the dissipation of heat, increasing the temperature of the fluid flowing through the valve. During operation of the system, if a low temperature condition is sensed in the system, power will be supplied to the pump, which pumps fluid through the valve at a controlled low pressure drop to result in a controlled heating of the fluid. When the fluid is restored to a desired temperature level, power to the pump is discontinued to terminate flow through the valve.
    Type: Grant
    Filed: June 2, 1992
    Date of Patent: June 1, 1993
    Assignee: Woodward Governor Company
    Inventor: David R. Bishoff
  • Patent number: 4889471
    Abstract: In a scroll compressor, an open end of an oil extraction pipe which is placed in oil stored in a bottom portion of a hermetic casing is positioned at a location higher than an open end of an oil suction pipe that opens in the same stored oil, and a thermostat is provided for sensing a temperature rise of a compressed gas to cause the compressor to be stopped. Accordingly, even when an amount of oil injected into the compressed gas decreases, an amount of oil necessary for lubrication of a bearing portion is assured. The provision of the thermostat enables the compressor to be stopped before an amount of supply of the lubrication oil to the bearing portion has decreased. It is, accordingly, possible to positively prevent burning of the bearing portion of a crankshaft.
    Type: Grant
    Filed: July 7, 1988
    Date of Patent: December 26, 1989
    Assignee: Hatachi, Ltd.
    Inventors: Yasushi Izunaga, Hiroaki Kuno, Shintaro Sado
  • Patent number: 4844702
    Abstract: A lubrication circuit connected to rotary vacuum pumps is composed of a hydraulic circuit and of the relative pump unit for lubrication and for auxiliary controls, including isolation of the negative pressure space from the pump on the stopping of the latter, with the aid of a closure member (10), for the operation of which use is made of the pressure of the fluid present in the pump discharge space with the aid of a duct (33, 34) between said discharge space and a means (8, 9) operating the closure member (10), which duct is subdivided into two portions between which is disposed a control member (27, 31) the operation of which is dependent on the oil pressure produced by the pump unit and propagated, with complete absence of flow, through a duct (23) so as to reach a control member (27, 31) which supervises the operation of the closure member (10).
    Type: Grant
    Filed: February 2, 1988
    Date of Patent: July 4, 1989
    Assignee: Officine Galileo SpA
    Inventors: Massimo Ceccherini, Silvio Dondoli
  • Patent number: 4605357
    Abstract: The invention comprises supplanting the usual, single, electrically-operated, blowdown valve, located on the receiver/separator tank of a gas compressor system with a pair of valves operatively arranged in parallel. The one valve operates normally in the manner of the supplanted valve, albeit with reduced venting capacity, and the other is held closed on starting of the compressor. This restricts the venting of the tank and causes its quick pressurization, to induce prompt oil injection for the compressor. A sensor detects the injection oil temperature and when the latter has achieved a given setpoint, the other, vent-restricting valve is opened. Accordingly, the method comprises sensing the temperature of the oil injected into the compressor and holding one of the paired venting valves closed until the oil temperature reaches the aforesaid given or predetermined setpoint.
    Type: Grant
    Filed: November 25, 1985
    Date of Patent: August 12, 1986
    Assignee: Ingersoll-Rand Company
    Inventor: Jeffrey S. Keith
  • Patent number: 4525129
    Abstract: An oil-sealed vacuum pump comprises an oil circuit for supplying a pump chamber and bearings of the vacuum pump with oil. The oil circuit includes first and second branch conduits leading to the bearings and the pump chamber, respectively. The vacuum pump further has an oil pump coupled to the oil circuit for driving oil therethrough, a valve assembly coupled to the oil circuit for shutting off oil supply to the pump chamber during standstill of the vacuum pump, and a pressure reducer coupled to the oil circuit for reducing the oil pressure to environmental pressure. The first branch conduit leading to the bearings is situated upstream of, and the second branch conduit leading to the pump chamber and the valve assembly are situated downstream of the pressure reducer as viewed in the direction of oil flow in the oil circuit.
    Type: Grant
    Filed: December 16, 1982
    Date of Patent: June 25, 1985
    Assignee: Leybold-Heraeus GmbH
    Inventors: Hanns-Peter Berges, Peter Frieden, Wolfgang Leier
  • Patent number: 4483667
    Abstract: A vacuum pump comprises a suction nipple valve including a cylinder, a piston slidably received therein and a movable valve closing member operatively connected to the piston. The vacuum pump further has a pressure medium conduit having a first end communicating with the cylinder; an inlet opening at a second end of the conduit for pressure medium to flow through the inlet opening to the piston; a control arrangement for closing and opening the inlet opening dependent upon run or standstill of the vacuum pump. In the closed state of the inlet opening an oil quantity is maintained above the inlet opening.
    Type: Grant
    Filed: December 16, 1982
    Date of Patent: November 20, 1984
    Assignee: Leybold-Heraeus GmbH
    Inventors: Hanns-Peter Berges, Peter Frieden, Hans-Peter Kabelitz
  • Patent number: 4441863
    Abstract: A variable discharge rotary compressor has a housing, a rotor disposed therein and vanes mounted on the rotor to cooperate with the housing and the rotor to define variable volume working chambers disposed close to and separated from an intake chamber by an end wall in which a communication passage is formed to communicate the working chambers with the intake chamber. The communication passage is located at a point where the working chambers are in their compression strokes. A valve is disposed in the communication passage to control the communication between the compression chambers and the intake chamber and is operative to communicate the compression chambers with the intake chamber to permit a part of the fluid in the compression chambers to be returned therefrom back into the intake chamber when the discharge of the compressor exceeds a predetermined discharge requirement.
    Type: Grant
    Filed: January 26, 1982
    Date of Patent: April 10, 1984
    Assignee: Nippondenso Co., Ltd.
    Inventors: Teruyuki Hotta, Yoshiki Kurokawa, Eiichi Nagasaku, Masao Yasunaga
  • Patent number: 4406588
    Abstract: A suction regulator for a compressor, in particular a screw compressor with oil injection, having an element which opens and closes the suction inlet to the compressor. The element closes the inlet due to the bias of a spring, opens the inlet against the bias of the spring in response to compressor discharge pressure and is positioned to regulate the suction in response to the system line pressure.
    Type: Grant
    Filed: November 3, 1980
    Date of Patent: September 27, 1983
    Inventor: Rudolf Hofmann
  • Patent number: 4399663
    Abstract: A control system for operating a vapor compression refrigeration system to prevent oil pump cavitation during startup of the refrigeration system is disclosed. The control system includes a differential pressure switch which is connected on one side to a reservoir which is in fluidic communication with the refrigeration system evaporator or compressor suction line. The pressure switch is connected on its other side directly to the evaporator or compressor suction line. In operation, the reservoir fills with vaporous refrigerant from the refrigeration system when the refrigeration system is shut down and the vaporous refrigerant flows through a restrictor valve back to the refrigeration system at startup of the refrigeration system. The size of the reservoir and restrictor valve are selected so that the differential pressure switch is activated and a control is generated when too rapid a decrease in evaporator or compressor suction line pressure is detected.
    Type: Grant
    Filed: November 27, 1981
    Date of Patent: August 23, 1983
    Assignee: Carrier Corporation
    Inventor: Benjamin F. Hesler
  • Patent number: 4229146
    Abstract: An air compressor assembly is provided having a high pressure air receiver, a compressor, an outlet port and an inlet port on said compressor, said inlet port having a normally closed spring loaded inlet valve, the improvement comprising a two position normally open spring loaded poppet valve on said compressor, oil pressure actuator means acting on said poppet valve opposite said spring, receiving pressure oil from a pressure lubricating system in said compressor to close said poppet valve against the spring in normal operation of the compressor, a pulsation damper having upper and lower chambers connected by a metering means between the compressor and air receiver, a connection from the compressor to the lower chamber delivering high pressure air thereto, a connection from the lower chamber to the air receiver, a connection from the upper chamber to the poppet valve on the same side as the spring, a pressure responsive actuator means selectively acting on the inlet valve, and a connection from the poppet va
    Type: Grant
    Filed: February 2, 1979
    Date of Patent: October 21, 1980
    Assignee: Airtek, Inc.
    Inventor: Paul W. Errett