Patent application number | Description | Published |
20090071144 | Actuator control system implementing adaptive flow control - An actuator control system is disclosed. The actuator control system may have a pump and at least one actuator. The actuator control system may further have an actuator valve configured to control the at least one actuator. The actuator control system may also have a pump pressure sensor configured to determine a pump pressure value and a load pressure sensor configure to determine a load pressure value. The actuator control system may additionally have a controller configured to receive the pump pressure value and the load pressure value. The controller may further be configured to compare the pump pressure value and the load pressure value, and selectively implement a primary control strategy and a secondary control strategy based on the comparison. | 03-19-2009 |
20090217653 | Control system for recovering swing motor kinetic energy - This disclosure relates to a hydraulic system and method that converts the kinetic energy generated by the operation of a swing motor into hydraulic potential energy and reuses the hydraulic potential energy for swing motor acceleration. An accumulator can be provided for storing exit oil from the swing motor that is pressurized by the inertia torque applied on the moving motor via movement of an upper structure of a machine. The pressurized oil in the accumulator can be reused to accelerate the swing motor by supplying pressurized oil to the swing motor. | 09-03-2009 |
20090277243 | Electrically controlled hydraulic valve calibration method and system - A method of calibrating an electrically controlled hydraulic valve having a known relationship between flow rate through the valve and displacement of a valve element is disclosed. The method includes ascertaining a first current level for actuating the electrically controlled hydraulic valve to move the valve element to a position adjacent an inlet port, and a first displacement of the valve element responsive to the first current level. The method also includes ascertaining a second current level for actuating the electrically controlled hydraulic valve to move the valve element from the position adjacent the inlet port to a position permitting flow through the inlet port, and ascertaining a second displacement of the valve element responsive to the second current level. The method further includes establishing a relationship between current and displacement associated with the electrically controlled hydraulic valve. | 11-12-2009 |
20120151904 | HYDRAULIC CONTROL SYSTEM HAVING ENERGY RECOVERY - A hydraulic control system for a machine is disclosed. The hydraulic control system may have a tank, a pump configured to draw fluid from the tank and pressurize the fluid, a swing motor configured to receive the pressurized fluid and swing a body of the machine relative to an undercarriage, and a tool actuator configured to receive the pressurized fluid and move a tool relative to the body. The hydraulic control system may also have an energy recovery device configured to convert hydraulic energy to mechanical energy, a first accumulator configured to store waste fluid received from the swing motor, and a second accumulator configured to store waste fluid received from the tool actuator. Stored waste fluid from at least one of the first and second accumulators may be selectively discharged into the energy recovery device. | 06-21-2012 |
20130000094 | HYDRAULIC CONTROL SYSTEM HAVING ENERGY RECOVERY KIT - An energy recovery retrofit kit for a hydraulic control system is disclosed. The energy recover retrofit kit may have a first accumulator and a second accumulator. The energy recover retrofit kit may also have a recovery valve block fluidly connectable between an existing pump and an existing motor of the hydraulic system. The recovery valve block may be configured to selectively fluidly communicate the first and second accumulators with the existing motor. | 01-03-2013 |
20130000289 | HYDRAULIC CONTROL SYSTEM HAVING SWING MOTOR ENERGY RECOVERY - A hydraulic control system for a machine is disclosed. The hydraulic control system may have a work tool movable to perform an excavation cycle having a plurality of segments, a motor configured to swing the work tool during the excavation cycle, and a pump configured to pressurize fluid directed to drive the motor. The hydraulic control system may also have at least one accumulator configured to selectively receive fluid discharged from the motor and to discharge fluid to the motor during the plurality of segments, and a controller configured to implement a plurality of modes of operation. Each of the plurality of modes of operation includes a different combination of segments during which the at least one accumulator receives and discharges fluid. | 01-03-2013 |
20130000290 | ENERGY RECOVERY SYSTEM HAVING ACCUMULATOR AND VARIABLE RELIEF - A swing energy recovery system for a machine is disclosed. The swing energy recovery system may have a pump configured to pressurize fluid, a motor driven by a flow of pressurized fluid from the pump, and an energy recovery arrangement configured to receive pressurized fluid discharged from the motor and selectively supply pressurized fluid to the motor. The swing energy recovery system may also have a pressure relief valve associated with the motor, and a controller in communication with the energy recovery arrangement and the pressure relief valve. The controller may be configured to selectively adjust a setting of the pressure relief valve based on an operating condition of the energy recovery arrangement. | 01-03-2013 |
20130004278 | HYDRAULIC CONTROL SYSTEM HAVING SWING ENERGY RECOVERY - A hydraulic control system for a machine is disclosed. The hydraulic control system may have a pump configured to pressurize fluid, and a motor driven by a flow of pressurized fluid from the pump. The hydraulic control system may also have a first accumulator configured to receive pressurized fluid discharged from the motor and to selectively supply pressurized fluid to the motor, and a second accumulator configured to receive pressurized fluid discharged from the motor and selectively supply pressurized fluid to the motor. | 01-03-2013 |
20130004280 | HYDRAULIC CONTROL SYSTEM HAVING SWING MOTOR ENERGY RECOVERY - A hydraulic control system for a machine is disclosed. The hydraulic control system may have a work tool movable through segments of an excavation cycle, a motor configured to swing the work tool during the excavation cycle, at least one accumulator configured to selectively receive fluid discharged from the motor and to discharge fluid to the motor during the excavation cycle, and a controller. The controller may be configured to receive input regarding a current excavation cycle of the work tool, and make a determination based on the input that the current excavation cycle is associated with one of a set of known modes of operation. The controller may be further configured to cause the at least one accumulator to receive fluid and discharge fluid during different segments of the excavation cycle based on the determination. | 01-03-2013 |
20130247999 | HYDRAULIC ACCUMULATOR PRE-CHARGE PRESSURE DETECTION - A system including a hydraulic accumulator, a pressure sensor, a fluid source and a data processor to detect a pre-charge pressure is provided. The hydraulic accumulator includes first and second fluid chambers and a separator therebetween. The hydraulic accumulator has an associated pre-charge pressure. The pressure sensor is connected to the first fluid chamber. The data processor is connected to the pressure sensor. The data processor is configured to determine a first and second rate of pressure changes, and a transition pressure between the first and second rates. The approximate pre-charge pressure is determined based on the transition pressure. | 09-26-2013 |
20130253854 | HYDRAULIC ACCUMULATOR HEALTH DIAGNOSIS - A system to diagnose a health of a hydraulic accumulator is provided. The hydraulic accumulator includes a first fluid chamber, a second fluid chamber, and a separator. The hydraulic accumulator has an associated pre-charge pressure. The system further includes a pressure sensor, a fluid source, a data processor, and a comparator. The pressure sensor and the fluid source are connected to the first fluid chamber. The data processor is configured to determine a first and second rate of pressure changes, and a transition pressure between the first and second rates. The approximate pre-charge pressure is determined based on the transition pressure. The comparator is configured to compare at least one of the determined pre charge pressure and the frictional forces with a pre-determined threshold range of pre-charge pressure and the frictional forces associated with the hydraulic accumulator to diagnose the health of the hydraulic accumulator. | 09-26-2013 |
20130283777 | HYDRAULIC CONTROL SYSTEM HAVING ENERGY RECOVERY - A hydraulic control system is disclosed for use with a machine. The hydraulic control system may have a pump, a tank, and an actuator. The hydraulic control system may also have at least a first valve configured to control fluid flow between the pump, the tank, a first chamber of the actuator, and a second chamber of the actuator; a second valve fluidly disposed between the second chamber and the tank; and a third valve fluidly disposed between the first and second chambers. The hydraulic control system may further have a controller configured to selectively cause the second valve to block fluid flow from the second chamber of the actuator to the tank, and to selectively cause the third valve to fluidly communicate the first and second chambers of the actuator when the second valve blocks fluid flow from the second chamber of the actuator to the tank. | 10-31-2013 |
20130318955 | ELECTRO-HYDRAULIC SYSTEM FOR RECOVERING AND REUSING POTENTIAL ENERGY - A hydraulic system includes a hydraulic actuator, a pump configured to supply fluid to the hydraulic actuator, and a first accumulator fluidly connected to the hydraulic actuator. The first accumulator is configured to store fluid received from the hydraulic actuator. The hydraulic system also includes a motor drivingly connected to the pump and fluidly connected to the first accumulator. The motor is configured to receive the stored fluid from the first accumulator to drive the pump. The hydraulic system further includes a first discharge valve fluidly connected between the first accumulator and the hydraulic actuator. The first discharge valve is configured to supply the stored fluid from the first accumulator to the hydraulic actuator without the stored fluid from the first accumulator circulating through the pump. | 12-05-2013 |
20130318959 | Hydraulic Circuits with Energy Conservation Features for Overrunning Load Conditions - A hydraulic system is disclosed that includes a hydraulic actuator having a head end, a rod end and a piston disposed therebetween. The system also includes a pump configured to supply fluid to both ends of the actuator. The system also includes an energy conservation system that is configured to reduce flow from the pump to the head end of the actuator and to increase flow from a make-up fluid circuit to the head end of the actuator during an overrunning load condition. The energy conservation system also increases flow from the pump to the head end of the actuator and decreases flow from the make-up circuit to the head end of the actuator after the overrunning load condition has ceased. | 12-05-2013 |
20140060018 | HYDRAULIC CONTROL SYSTEM - A hydraulic control system includes an implement movable to perform an excavation cycle having a plurality of segments, a variable displacement motor configured to swing the implement at a desired speed during the excavation cycle, and a pump configured to pressurize fluid directed to drive the motor. The system further includes an accumulator configured to selectively receive fluid discharged from the motor via a charge valve, and to discharge fluid to the motor via a discharge valve. The system includes a selector valve fluidly connected to the charge valve and the discharge valve. The system also includes a controller configured to vary displacement of the motor, resulting in the desired speed. | 03-06-2014 |
20140060021 | HYDRAULIC CONTROL SYSTEM HAVING SWING OSCILLATION DAMPENING - A hydraulic control system is disclosed. The hydraulic control system may have an input device to generate a first signal indicative of a desired swing motor movement, and a control valve configured to selectively pass fluid to the swing motor and drain from the swing motor to drive the swing motor based on the first signal. The hydraulic control system may also have a pressure sensor to generate a second signal indicative of a swing motor pressure, a speed sensor configured to a third signal indicative of a swing motor speed, and a controller configured to make a comparison of at least one of the swing motor speed and the swing motor pressure with a threshold speed and a threshold pressure, and open the control valve to drain fluid from the swing motor to the tank based on the comparison when the input device is in a neutral condition. | 03-06-2014 |
20140060022 | HYDRAULIC CONTROL SYSTEM HAVING SWING MOTOR ENERGY RECOVERY - A hydraulic control system is disclosed for use with a machine. The hydraulic control system may have a tank, a pump, a swing motor, and at least one control. The hydraulic control system may further have an accumulator configured to receive fluid from and supply fluid to the swing motor, a charge valve movable to allow fluid flow from the swing motor into the accumulator, and a discharge valve movable to allow fluid flow from the accumulator to the swing motor. The hydraulic control system may additionally have a controller in communication with the at least one control valve, the charge valve, and the discharge valve. The controller may be configured to detect an acceleration of the swing motor, selectively cause the discharge valve to assist the acceleration, and selectively move the charge valve to an open position to recover energy associated with pressure spikes occurring during the acceleration. | 03-06-2014 |
20140060024 | HYDRAULIC CONTROL SYSTEM HAVING SWING MOTOR RECOVERY - A hydraulic control system is disclosed for use with a machine. The hydraulic control system may have a tank, a pump, a swing motor, and at least one control valve configured to control fluid flow between the pump, the swing motor, and the tank. The hydraulic system may also have an accumulator configured to selectively receive pressurized fluid discharged from the swing motor and selectively supply pressurized fluid to the swing motor, at least one accumulator valve, and a controller. The controller may be configured to receive input indicative of a difference between desired and actual speeds of the swing motor, and determine if the swing motor is accelerating or decelerating based on the difference. The controller may also be configured to control the at least one accumulator valve to cause the accumulator to selectively receive or supply pressurized fluid only when the swing motor is accelerating or decelerating. | 03-06-2014 |
20140060025 | HYDRAULIC CONTROL SYSTEM HAVING ELECTRONIC FLOW LIMITING - A hydraulic control system is disclosed for use with a machine. The hydraulic control system may have a tank, a pump, an actuator, and a control valve configured to direct fluid from the pump to the actuator and from the actuator to the tank. The hydraulic control system may also have a pressure sensor to generate a first signal indicative of a pressure differential across the control valve, an operator input device to generate a second signal indicative of a desired movement of the actuator, and a controller. The controller may be configured to make a first determination of an opening amount of the control valve based on the second signal, and to make a second determination based on the first signal of whether the opening amount will result in overspeeding of the actuator. The controller may also be configured to reduce the opening amount based on the second determination. | 03-06-2014 |
20140060031 | HYDRAULIC CONTROL SYSTEM HAVING SWING ENERGY RECOVERY - A hydraulic control system for a machine is disclosed. The hydraulic control system may have a tank, a pump, and a fluid actuator. The hydraulic control system may further have an accumulator configured to selectively receive pressurized fluid discharged from the fluid actuator and selectively supply pressurized fluid to the fluid actuator. The hydraulic control system may also have a pressure sensor configured to generate a signal indicative of a pressure of the accumulator, a charge valve, a discharge valve, and a controller in communication with the control valve, the charge valve, and the discharge valve. The controller may be configured to detect stall of the fluid actuator, to make a comparison of the pressure of the accumulator with a threshold pressure, and to selectively move the charge valve to charge the accumulator or move the discharge valve to discharge the accumulator during the stall based on the comparison. | 03-06-2014 |
20140119867 | ENERGY RECOVERY SYSTEM HAVING INTEGRATED BOOM/SWING CIRCUITS - An energy recovery system for a machine is disclosed. The energy recovery system may have a boom circuit with at least a one linear actuator configured to move a work tool, and a boom accumulator configured to selectively collect pressurized fluid from the at least one linear actuator and to discharge pressurized fluid back to the at least one linear actuator. The energy recovery system may also have a swing circuit with a swing motor configured to move the work tool, and a swing accumulator configured to selectively collect pressurized fluid from the swing motor and discharge pressurized fluid back to the swing motor. The energy recovery system may further have a common accumulator passage fluidly connecting the boom accumulator and the swing accumulator. | 05-01-2014 |
20140119868 | ENERGY RECOVERY SYSTEM HAVING PEAK-SHAVING ACCUMULATOR - An energy recovery system for a machine is disclosed. The energy recovery system may have a tank, a pump configured to draw fluid from the tank and pressurize the fluid, an actuator, and an actuator control valve movable to direct pressurized fluid from the pump to the actuator and from the actuator to the tank to move the actuator. The energy recovery system may also have a motor connected to selectively receive fluid discharged from the actuator and mechanically connected to the pump, and an accumulator configured to store fluid discharged from the motor and to direct stored fluid to the motor to drive the pump. | 05-01-2014 |
20140150415 | Energy Recovery Hydraulic System - A method and system for accumulating and using recovered hydraulic energy that includes a hydraulic actuator and a pump configured to supply pressurized fluid to the hydraulic actuator. An energy recovery system includes a hydraulic motor, a charge valve and an accumulator configured to store fluid from the hydraulic actuator. The charge valve is operatively connected between the hydraulic actuator and the accumulator and between the accumulator and the hydraulic motor and is configured to place the hydraulic actuator in fluid communication with the accumulator and to place the accumulator in fluid communication with the hydraulic motor. A directional valve is operatively connected between the pump and the hydraulic actuator. The directional valve is configured to place the pump in fluid communication with the hydraulic actuator and to direct the flow of hydraulic fluid exiting the hydraulic actuator to the charge valve in an energy recovery mode. | 06-05-2014 |
20140208728 | Method and Hydraulic Control System Having Swing Motor Energy Recovery - A hydraulic control system includes a swing control valve between a pump and a swing motor to control flow to/from the swing motor, and a selector valve between an accumulator and the swing motor to regulate fluid flow. A controller is configured to receive inputs indicative of the pressure differential between the accumulator and conduit between the pump and swing motor, and a swing motor command, calculate a target swing motor flow based on the swing motor command input, and modulate operation of the swing control valve and the selector valve to regulate a swing speed. | 07-31-2014 |
20140230420 | ENERGY RECOVERY SYSTEM FOR HYDRAULIC MACHINE - An energy recovery system is disclosed for use with a hydraulic machine. The energy recovery system may have a tank, a pump configured to draw fluid from the tank and pressurize the fluid, an actuator, and an actuator control valve movable to direct pressurized fluid from the pump to the actuator and from the actuator to the tank to move the actuator. The energy recovery system may also have a motor mechanically connected to a rotary device and configured to selectively receive fluid discharged from the actuator, and at least one valve movable to selectively redirect fluid exiting the motor back to the actuator. | 08-21-2014 |
20140283915 | Hydraulic Control System Having Relief Flow Capture - A hydraulic circuit may be provided. The circuit may include: a pump to supply pressurized fluid to a circuit; a supply passageway coupled between the pump and the circuit; a relief flow passageway coupled between the supply passageway and a fluid reservoir; a relief flow capture circuit coupled to the relief flow passageway, the relief flow capture circuit including: a first valve configured to move from a closed position to an open position when a first pressure is detected; a second valve in fluid communication with the first valve, the second valve configured to move from a closed position to an open position when a second pressure is detected wherein the second pressure is lower than the first pressure; and an accumulator located between the first and second valves and in fluid communication with both the first and second valves, the accumulator configured to store fluid flowing through the first valve when the first pressure valve is in an open position, the accumulator further configured to outflow fluid through the second valve when the second valve is in an open position. | 09-25-2014 |
20140325972 | Hydraulic Hybrid Boom System Hydraulic Transformer - A hydraulic system includes a hydraulic actuator, an accumulator, an accumulator charge valve, and a hydraulic transformer fluidly connected between the accumulator charge valve and the accumulator. The hydraulic transformer includes a transformer motor mechanically coupled to a transformer pump. The accumulator charge valve is fluidly connected between the transformer motor and the hydraulic actuator. The transformer pump is sized to permit a maximum flow therethrough of no more than three-quarters of a flow permitted through the transformer motor. | 11-06-2014 |
20150075147 | HYDRAULIC CONTROL SYSTEM FOR MACHINE - A hydraulic control system for a machine is disclosed. The hydraulic control system includes a pump configured to pressurize a fluid, and a swing motor selectively driven by pressurized fluid from the pump. The swing motor is configured to move a part of the machine. The hydraulic control system also includes a controller in communication with the pump. The controller is configured to receive an input indicative of a difference between a desired speed and an actual speed of the swing motor, and determine if the swing motor is accelerating, decelerating, or operating at neutral mode. The controller is configured to determine an amount of return fluid from an actuator of the machine that is available as makeup fluid for the swing motor if the swing motor is operating at neutral mode. The controller is configured to control the pump based on at least the amount of return fluid. | 03-19-2015 |