Entries |
Document | Title | Date |
20080202110 | Hydraulic Control Arrangement - The invention discloses a hydraulic control arrangement for controlling a number of consumers, particularly of a mobile working machine. In addition to the consumers of the control arrangement, an additional consumer should be able to be connected to a power beyond port. All consumers and power beyond consumers are supplied with hydraulic fluid by a pump. An input pressure scale is provided downstream of the pump, and the greater of the load pressures of the consumers or of the at least one power beyond consumer is applied to the control port of said input pressure scale. | 08-28-2008 |
20080209902 | Hydraulic system - A hydraulic system for actuating a clutch and/or a variable speed drive unit of a belt-driven conical-pulley transmission of a vehicle, such as a commercial vehicle, and having a variable transmission ratio and a torque sensor. The hydraulic system includes at least one hydraulic energy source. A selector and check valve is provided for supplying additional components besides the torque sensor and is connected between the hydraulic energy source, the additional components, and the torque sensor in such a way that the torque sensor includes priority in being supplied with hydraulic medium. | 09-04-2008 |
20080250782 | HYDRAULIC CONTROL DEVICE OF WORKING MACHINE - A rotation prioritizing valve serving as a flow rate control valve of a hydraulic pilot type is provided on the meter-in side of an arm cylinder. At the time of a combined operation of arm pulling and rotation, the rotation prioritizing valve is activated by rotation pilot pressure so that a meter-in flow rate of the arm cylinder is throttled to prioritize rotation movement. On the premise of the above, a switching valve is provided in a pilot line of the rotation prioritizing valve and switched so as to release a throttling effect of the rotation prioritizing valve when boom lowering movement is added to the combined operation of arm pulling and rotation so that a rotation prioritizing function is cancelled. | 10-16-2008 |
20080256939 | Device for Managing the Displacement of a Hydraulic Motor or a Group of Hydraulic Motors - A motor having two series of distribution ducts each having two groups of ducts. The displacement selector is able to occupy a large displacement position in which the first groups of distribution ducts of the first series are connected to a main duct while the second groups are connected to the other main duct, and a small displacement configuration in which the first group of distribution ducts of the first series is connected to a main duct, the second group of distribution ducts of the first series is connected to the other main duct and a bypass connection exists between the first and the second group of distribution ducts of the second series. The device has a restriction in order, in the small displacement configuration, to restrict this bypass connection. | 10-23-2008 |
20090025380 | Fixed/variable hybrid system - A fixed/variable hybrid system has modified constant flow open center hydraulic valves (“fixed/variable valves”), including an open center core, spools, a power core, and a tank galley. A small fixed displacement pump provides fluid at a constant rate to the open center core. A variable displacement piston pump provides fluid directly to the power core as needed. Activation of spools partially restricts the open center core causing an increase in fluid pressure that is communicated to the variable displacement piston pump's load sense signal port, causing the pump to increase fluid flow and pressure to the power core. Activated spools direct pressurized fluid from the power core to the applications through selected hydraulic ports. Activated spools also direct fluid flow from selected hydraulic ports via the tank galley to a hydraulic tank. Pumping the majority of fluid only on an as-needed basis results in significant efficiencies. | 01-29-2009 |
20090031719 | Hydraulic Drive System - The hydraulic drive system comprises an engine | 02-05-2009 |
20090031720 | Hydraulic circuit for heavy equipment having variable control device - A hydraulic circuit for heavy equipment having a variable control device is provided, in which variable relief valves for variably controlling operating pressure and flow rate of an option attachment are installed inside a main control valve, and pressure of the variable relief valves is variably controlled through selection of a preset option working mode. The hydraulic circuit includes at least one variable displacement hydraulic pump; a main relief valve installed on an upstream side of a discharge flow path of the hydraulic pump; an option attachment connected to the hydraulic pump; a main control valve installed in a flow path between the hydraulic pump and the option attachment; port relief valves, installed inside the main control valve, for being proportionally controlled so as to variably control relief pressure required for the option attachment in accordance with pilot signal pressure inputted from an outside; and a proportional relief valve, installed outside the main control valve, for variably controlling the pilot signal pressure inputted to the port relief valves in accordance with an electric signal inputted from an outside. | 02-05-2009 |
20090064673 | HYDRAULIC CONTROL DEVICE - A hydraulic control device according to the invention is of load-sensing design and serves to actuate a first hydraulic load and a second hydraulic load. Also provided are a first control valve for actuating the first hydraulic load and a second control valve for actuating the second hydraulic load. A first load signal can be measured on the basis of a load pressure with which the first hydraulic load is acted on, and a second load signal can be measured on the basis of a load pressure with which the second hydraulic load is acted on. Pressure medium from a pressure medium source can be supplied in parallel to the first control valve and to the second control valve. A load signal path can, in order to actuate an adjusting element which is assigned to the pressure medium source, be acted on with a highest presently measured load signal. A limiting device allows the second load signal to be limited to a predefined signal limit value. A switching means can be actuated by means of the second load signal such that, at the latest when the second load signal reaches the signal limit value, the signal conveyed on the load signal path is limited by the limiting device. | 03-12-2009 |
20090071140 | Hydraulic circuit, particularly for camshaft adjusters, and corresponding control element - The invention relates to a valve and suitable hydraulic circuit, especially for camshaft adjusters of an internal combustion engine. The hydraulic circuit comprises a number of check valves or two-way valves operating as check valves, in order to provide a rapid camshaft adjuster with a high regulating quality. | 03-19-2009 |
20090107132 | HYDRAULIC SUPPLY SYSTEM WITH AN ADJUSTABLE PUMP - The invention relates to a hydraulic supply system with an adjustable pump for supplying at least one safety-critical consumer to be supplied as a matter of priority and at least one non-safety-critical consumer. The adjustable pump control is configured for adapting the flow generated by the pump to the instantaneous requirements of the consumers and has a flow control valve for controlling the pump. The adjustable pump control further comprises switching, hydraulically actuated valves which cause the priority supply of the at least one safety-critical consumer and are activated by a hydraulic release signal generated in the region of the at least one safety-critical consumer. | 04-30-2009 |
20090107133 | Procedure to align working equipment mounted to a liftable and lowerable hositing frame of a working machine - The procedure, provides a simple and retro-fittable manner to align working equipment, mounted to a liftable and lowerable hoisting frame of a working machine in a tilting way to comply with required positions, wherein the working equipment is shifted via a tilting cylinder in other directions than the hoisting framing. The tilting cylinder is supplied with hydraulic oil from a hydraulic pump for the working hydraulic system by a direct-operated control valve, and secondary consumers of the working machine being supplied with hydraulic oil from at least one other hydraulic pump. Once the driver operates a triggering element, the two hydraulic connections of the tilting cylinder are also connected to the hydraulic pump for the secondary consumers by a switch-over valve activated by the control equipment, therefore shifting the tilting cylinder in the direction of the neutral position of the working equipment. | 04-30-2009 |
20090113887 | Hydraulic Drive Device - To permit driving a tilt cylinder and an angle cylinder at relatively low speed and also to permit driving an additional actuator at high speed. | 05-07-2009 |
20090139224 | Device and method of continuously variable transmission of traveling vehicle - A variable capacity pump and two variable capacity motors are connected in a closed circuit. First to fourth drive gears are fitted to motor shafts of the variable capacity motors via clutches. A first driven gear, which meshes with the first and third drive gears, and a second driven gear which meshes with the second and fourth drive gears are fitted to an output shaft. Equivalent capacities of the variable capacity motors are made different. Control is exerted such that the capacities are decreased to zero in order of equivalent capacities. To decrease the capacity of each variable capacity motor, the gear change ratio of the variable capacity motor the capacity of which has decreased to zero is changed to decrease the equivalent capacity and, at the same time, the capacity is increased to maximum. This increases the gear change ratio for the continuously variable transmission and controls acceleration. | 06-04-2009 |
20090313986 | HYDRAULIC ASSEMBLY FOR DRIVING AND CONTROLLING SMALL HYDRAULIC UNITS - A hydraulic assembly for driving and controlling small hydraulic units, such as hydraulic cylinders of a brake and/or clutch of a forestry winch, is disclosed. The hydraulic assembly includes a means for establishing and also maintaining a pre-determined pressure of a hydraulic media. The hydraulic assembly is characterized by as low as possible hydraulic loss. Also, a quantity of hydraulic media required for a regular operation and maintaining the pressure within the hydraulic assembly is as low as possible. | 12-24-2009 |
20100018197 | PIPE LAYER HAVING SWING SPEED ADJUSTABLE SYSTEM - A pipe layer having a swing speed adjustable system is provided, which can be used as a pipe layer or an excavator through replacement of attachments in accordance with work conditions, so that it serves as the pipe layer when it is required to pull up and carry a heavyweight oil pipe in order to lay the oil pipe under the ground, while it serves as the excavator when a quick swing work is required. The pipe layer having a swing speed adjustable system includes first and second variable displacement hydraulic pumps connected to an engine, control valves installed in a center bypass path of the first hydraulic pump, control valves installed in a center bypass path of the second hydraulic pump, a straight traveling valve installed on an upstream side of the center bypass passage of the first hydraulic pump to supply the hydraulic fluid from the first and second hydraulic pumps to a boom cylinder, a swing motor, a winch motor, and left and right traveling motors, respectively, and a variable load-hold check valve installed in an inlet-side flow path of the swing motor control valve to variably adjust a stroke of a poppet so that the amount of hydraulic fluid being supplied to the swing motor can be variably adjusted. | 01-28-2010 |
20100031648 | HYDRAULIC FLOW SHARING SYSTEM FOR EXCAVATING AND PIPE LAYING WORK - A hydraulic flow sharing system for excavating and pipe laying work is provided, which can prevent the abrupt change of a traveling speed during traveling through compulsory sharing of the flow rate applied to a working device and a traveling apparatus when a combined operation, in which the traveling apparatus and the working device such as a boom are simultaneously driven, is performed. | 02-11-2010 |
20100043420 | HYDRAULIC SYSTEM FOR CONSTRUCTION EQUIPMENT - A hydraulic system for construction equipment is provided, which can increase the driving speed of a corresponding working device by making hydraulic fluid of a hydraulic pump, which is added to the hydraulic system having two hydraulic pumps in the construction equipment, join hydraulic fluid on the working device side, and can intercept the supply of hydraulic fluid from the working device side to a traveling apparatus side when the working device and the traveling apparatus are simultaneously manipulated. | 02-25-2010 |
20100050624 | HYDROSTATIC TRAVEL DRIVE HAVING TWO HYDRAULIC MOTORS - The invention relates to a hydrostatic drive having one hydraulic pump unit ( | 03-04-2010 |
20100071358 | Hydraulic System of Work Machine - A hydraulic system of a work machine with a hydraulically controlled implement includes: an operating oil flow passage for flowing operating oil from a main pump; a boost flow oil passage for supplying operating oil to the operating oil flow passage; a connection unit for connecting the implement which is provided downstream of the confluence on the operating oil flow passage; a controller for controlling the high-flow valve; and a high-flow switch which is connected to the controller and is configured to effect or cancel a command of the amount increase on a high-flow valve. Annunciation is made when the connection unit is connected to a high-flow actuator for the implement requiring an amount increase of the operating oil, and the amount increase is effected by the high-flow valve in accordance with an operation of the high-flow switch. | 03-25-2010 |
20100095663 | Travel Control Apparatus for Working Vehicle - There are provided: a first circuit for traveling HC | 04-22-2010 |
20100293935 | HYDROSTATIC GROUND DRIVE CONTROL SYSTEM FOR A WORK MACHINE WITH SMOOTH TRANSITION BETWEEN SPEED RANGES - The control system allows selecting from multiple speed ranges for the ground drive of a work machine without a mechanical transmission. The system does this by controlling a variable displacement fluid pump supplying fluid to variable displacement fluid motors driving ground wheels of the machine. When a speed range is selected, the system automatically controls displacement of the pump and motors to provide operability within the range by movement of a speed input device. When another range is selected, the system provides a seamless transition, including to and from reverse, as no disengaging and engaging of mechanical gears, or change in the speed input position, is required. The system can also automatically adjust ground speed for the new speed range for the current speed input position. | 11-25-2010 |
20100293936 | HYDRAULIC SYSTEM WITH IMPROVED COMPLEX OPERATION - A hydraulic system with an improved complex operation is provided, which can prevent the generation of shock in a boom by delaying pressure supply during start and end of pilot signal pressure supplied to a spool for controlling an option device when a boom ascending operation and an operation of an option device are simultaneously performed or when such a simultaneous operation of the boom and the option device switches over to an independent operation of the boom. The hydraulic system with an improved complex operation includes main hydraulic pumps and a pilot pump; a boom cylinder and an option device; a main control valve including a boom spool and an option device spool which are shifted by a pilot signal pressure from the pilot pump; an operation lever which controls the boom spool; an option operation pedal which controls the option device spool; a confluence spool for controlling the option device; and a controller which outputs an electric control signal to a proportional control valve for the option device so as to delay pilot signal pressure supplied to the confluence spool during start and end of the pilot signal pressure supply when a complex operation for simultaneously operating the boom cylinder and the option device is performed. | 11-25-2010 |
20100300086 | HYDRAULIC CONTROL ARRANGEMENT AND DISTRIBUTION VALVE SECTION - A hydraulic control arrangement and a method for pressure medium supply of hydraulic consumers are disclosed, comprising an LS pump which can be controlled by a pump regulator dependent on the highest load pressure of the consumers. The pressure medium volume flow to each consumer is adjusted using a metering aperture, wherein on controlling a consumer a higher pressure than the load pressure is signaled to the LS pump regulator, so that the LS pump is controlled according to the higher pressure rather than the low load pressure of said consumer. | 12-02-2010 |
20110067391 | HYDRAULIC DRIVE SYSTEM FOR SAND AND SALT SPREADERS - A hydraulic drive system for a spreader used to distribute a road surface treatment material, such as sand or salt, across a road surface. The hydraulic drive system enables the use of pressure-compensated proportional control valves in series relationship with the auger and spinner motors, by the provision of small restricted flow passages across the outlets of the valves. | 03-24-2011 |
20110131967 | BRAKE SYSTEM AND VEHICLE COMPRISING A BRAKE SYSTEM - A vehicle and a brake system for a vehicle include at least one hydraulic pump, wherein the at least one hydraulic pump is connected to an input fluid conduit and an output fluid conduit. A flow resistance unit is provided in the output fluid conduit of the at least one hydraulic pump for being selectively coupled into the output fluid conduit when brake torque is requested. | 06-09-2011 |
20110179783 | DEVICE TO ACTIVELY CONTROL THE VIBRATIONS OF AN ARTICULATED ARM TO PUMP CONCRETE - The device to actively control the vibrations of an articulated arm consisting of a plurality of segments each comprising at least its own actuator associated with a hydraulic drive circuit including a block valve. At least one of said actuators is associated with an auxiliary control circuit of the vibrations, comprising at least a sensor able to detect the vibrations and/or the position of one or more segments, a processing unit to process the signals of the sensor/sensors and a pump commanded by the processing unit and cooperating with said block valve. The auxiliary control circuit is associated with the hydraulic drive circuit. | 07-28-2011 |
20110265467 | CONTROL DEVICE FOR HYBRID CONSTRUCTION MACHINE - A control device for a hybrid construction machine includes a discharge pressure introduction passage that leads a discharge pressure from a variable volume pump to a regulator, and a load pressure introduction passage that leads one of a maximum load pressure of respective actuators and a load pressure of a hydraulic motor to the regulator. A controller, having determined that the actuators are in an inoperative condition on the basis of a detection result from an operating condition detector, excites a solenoid of a solenoid pilot control valve such that a discharge oil from the variable volume pump is led to the hydraulic motor, and controls the regulator such that a differential pressure between the discharge pressure of the variable volume pump and the load pressure of the hydraulic motor is kept constant. | 11-03-2011 |
20120023921 | HYDRAULIC TOOL CONTROL WITH ELECTRONICALLY ADJUSTABLE FLOW - The present disclosure provides embodiments directed towards a system for the control of hydraulic output by a hydraulic power source. In one embodiment, a system is provided. The system includes a hydraulic supply system having a drive, a hydraulic pump coupled to the drive, a first hydraulic output configured to supply a first flow of a hydraulic fluid from the hydraulic pump to a hydraulic lift, a second hydraulic output configured to supply a second flow of the hydraulic fluid from the hydraulic pump to a first hydraulic tool, and a controller configured to adjust a speed of the drive in response to a feedback indicative of a first load by the hydraulic lift, a second load by the first hydraulic tool, or a combination thereof. | 02-02-2012 |
20120023922 | OPERATOR INTERFACE FOR HYDRAULIC TOOL CONTROL - The present disclosure provides embodiments directed towards a system for the control of hydraulic output by a hydraulic power source. In one embodiment, a system is provided. The system includes a hydraulic supply system having a drive, a hydraulic pump coupled to the drive, a first hydraulic output configured to supply a first flow of a hydraulic fluid from the hydraulic pump to a hydraulic lift, a second hydraulic output configured to supply a second flow of the hydraulic fluid from the hydraulic pump to a first hydraulic tool, and a controller configured to adjust a speed of the drive in response to a feedback indicative of a first load by the hydraulic lift, a second load by the first hydraulic tool, or a combination thereof. | 02-02-2012 |
20120204550 | ACTIVE 3D.O.F. STIFFNESS ELEMENT - A dynamic three-degree-of-freedom actuator/transducer element comprising at least three piezoceramic actuators and force sensors, as integrated stacks, which are preloaded in the housing by a low-stiffness tension bar, and are constrained, by means of a flexible shell, against shear force and torsion moment, whereby the element, when powered by external voltage source, this actuator/transducer is able to generate a dynamical axial force and displacement and dynamical bending and moment in the two principal tilt degrees of freedom around two orthogonal axes perpendicular to the principal displacement and when subjected to an axial force or a tilting moment, the transducer is able to generate charges that are proportional to the said exerted force and moments. | 08-16-2012 |
20120247094 | HYDRAULIC PUMP CONTROL DEVICE FOR CONSTRUCTION MACHINE - A pump control device for a construction machine includes a pump regulator, a pump pressure detector, a travelling operation detector, a working operation detector, and a controller instructing the pump flow rate depending on the pump pressure to the pump regulator. The controller stores first and second P-Q characteristics as a horsepower characteristic and instructs the pump flow rate to the pump regulator, based on the first P-Q characteristic when a travelling operation is detected, and based on the second P-Q characteristic when a working operation is detected. The second P-Q characteristic is equal to the first P-Q characteristic in a low-pressure region while is one giving a low characteristic relatively to the first P-Q characteristic so as to increase a horsepower difference as the pump pressure increases, in intermediate-pressure and high-pressure regions. | 10-04-2012 |
20120260646 | HYDRAULIC CIRCUIT CONTROL DEVICE AND WORK MACHINE - A controller controls the solenoid-operated variable pressure relief valves that are provided to control, at set pressures that can be electrically commanded, pressure of hydraulic oil fed to an attachment cylinder. The controller is provided with a control logic that is capable of controlling the aforementioned solenoid-operated variable pressure relief valves. The control logic performs the aforementioned calculation by compensating for pressure override characteristics of each solenoid-operated variable pressure relief valve based on input signals related to the set relief pressure for and a relief valve passing flow rate of the solenoid-operated variable pressure relief valve, and outputting to the solenoid-operated variable pressure relief valve command signals related to the adjusted set relief pressure resulting from the compensation of the pressure override characteristics. | 10-18-2012 |
20120291427 | ATTACHMENT CONTROL APPARATUS FOR HYDRAULIC EXCAVATOR - In an attachment control apparatus for a hydraulic excavator having a hydraulic circuit that includes a hydraulic pump, a plurality of actuators having a breaker which is an attachment actuator, and a plurality of flow control valves having an attachment flow control valve that is switched by operation pilot pressure from a control pedal device to supply delivery fluid of the hydraulic pump to the attachment actuator, if the control pedal device is operated in a state where an attachment mode is not selected by an attachment selection device, the movement of the attachment actuator is limited. Thus, failure and reduced life of the attachment and other hydraulic devices can be prevented in the event that an operator has forgotten to switch from a normal mode to an attachment mode and has operated the attachment. | 11-22-2012 |
20130014500 | Drive Train of a Mobile MachineAANM WELSCHOF; BernwardAACI GrossostheimAACO DEAAGP WELSCHOF; Bernward Grossostheim DEAANM KRITTIAN; LukasAACI AschaffenburgAACO DEAAGP KRITTIAN; Lukas Aschaffenburg DE - A drive train of a vehicle has a drive motor and a traction drive driven by the drive motor. A hydraulic work system has at least one hydraulic pump driven by the drive motor. To deliver torque into the drive train and/or to absorb torque from the drive train, the drive train is provided with an additional hydraulic machine which can be placed in communication with a hydraulic pressure accumulator and/or a tank and can be operated as a pump and a motor in the same direction of rotation. The hydraulic machine has an inlet connection and an outlet connection and a switching valve device is provided to control the connection of the inlet connection and the outlet connection with the pressure accumulator or the tank. | 01-17-2013 |
20130098024 | Hydraulic System - A hydraulic system includes a first pump, a first actuator fluidly connected to the first pump via a first closed-loop circuit, a second pump, and a second actuator fluidly connected to the second pump via a second closed-loop circuit. The system also includes a third pump, a third actuator fluidly connected to the third pump via a third closed-loop circuit, a fourth pump, and a fourth actuator fluidly connected to the fourth pump via a fourth closed-loop circuit. The system further includes a first combining valve configured to combine fluid from the first and second circuits, a second combining valve configured to combine fluid from the second and third circuits, and a third combining valve configured to combine fluid from the third and fourth circuits. The system also includes a fourth combining valve configured to combine fluid from the first and fourth circuits. | 04-25-2013 |
20130152573 | HYBRID SYSTEM FOR CONSTRUCTION MACHINE - When the actuator drive torque of a hydraulic pump is lower than a switching torque τ0, a controller closes a solenoid switching valve and makes a rotary electric machine function as a generator. With the increase in the actuator drive torque, the controller controls a pressure compensated flow control valve so that the flow rate of hydraulic fluid supplied from the hydraulic pump to a rotary hydraulic device decreases. When the actuator drive torque is higher than the switching torque, the controller opens the solenoid switching valve, makes the rotary electric machine function as an electric motor, and controls the pressure compensated flow control valve so that the hydraulic fluid discharged by the hydraulic pump is not supplied to the rotary hydraulic device. Consequently, shocks due to flow rate fluctuation are prevented when operational states of the rotary hydraulic device and the rotary electric machine are switched. | 06-20-2013 |
20130219876 | AUTOMATIC TRANSMISSION FOR HYBRID VEHICLE - An automatic transmission for a hybrid vehicle comprising a first hydraulic pressure supply source driven with an internal combustion engine; a second hydraulic pressure supply source driven independently of the first supply source; and a regulator valve regulating hydraulic pressure produced by the supply sources. A first oil passage supplying line pressure regulated by the regulator valve to a hydraulic servo operating a friction engagement element; a second oil passage supplying hydraulic pressure discharged from the regulator valve to a lubricated portion via an oil cooler; and a thud oil passage merged with the second oil passage at a point downstream of the oil cooler supplying the hydraulic pressure of the second supply source to the lubricated portion. A first reverse flow prevention mechanism is disposed between the oil cooler and the merging point to prevent reverse flow of hydraulic pressure. | 08-29-2013 |
20130255243 | TURNING CONTROL APPARATUS - A turning control apparatus includes a turning body and a hydraulic motor to turn the turning body. A high-pressure relief circuit relieves hydraulic pressure of a first hydraulic line at a first relief pressure, the first hydraulic line supplying an operating oil to drive the hydraulic motor. A hunting reduction circuit relieves a hydraulic pressure of a second hydraulic line at a pressure lower than the first relief pressure, the second hydraulic line being connected to a deceleration-side hydraulic port from which the operating oil is discharged when the hydraulic motor is being driven. The hunting reduction circuit connected to the deceleration-side hydraulic port is caused to open before an operation lever to operate turning of the turning body returns to a neutral position. | 10-03-2013 |
20130269332 | ENERGY RECYCLING SYSTEM FOR A CONSTRUCTION APPARATUS - An energy recycling system is disclosed. When a construction apparatus performs a combined operation of a boom down operation and an arm out operation, hydraulic energy returned in the boom down operation is recycled for the arm out operation by the energy recycling system. An energy recycling system for a construction apparatus according to the present invention includes: a first hydraulic pump; a second hydraulic pump; an arm cylinder including a low-pressure chamber connected to the first hydraulic pump through an arm out supply passage; an arm out return passage connecting a high pressure chamber of the arm cylinder to a hydraulic tank; a boom cylinder including a low-pressure chamber connected to the second hydraulic pump through a boom down supply passage; a boom down return passage connecting a high pressure chamber of the boom cylinder to a hydraulic tank; a joining and recycling passage connecting the boom down return passage and the arm out supply passage to each other in parallel; a recycling passage connecting the boom down return passage and the boom down supply passage to each other in parallel; and a plurality of detecting means that detect pressure of the arm cylinder and pressure of the boom cylinder, respectively, to determine whether a hydraulic fluid, returned from the boom cylinder in a combined operation of a boom down operation and an arm out operation, is recycled. | 10-17-2013 |
20130283775 | OIL PRESSURE SYSTEM FOR WHEEL LOADER - The present disclosure provides an oil pressure system for a wheel loader with an improved raising process of a boom, thereby, especially, decreasing impact generated when the boom approaches a maximum height during loading work. | 10-31-2013 |
20130318956 | ELECTRIC CONSTRUCTION MACHINE - Provided is an electric construction machine capable of avoiding a situation where charging is difficult to achieve due to the exhaustion of a battery device. An electrically-operated hydraulic excavator includes an electric motor, a hydraulic pump that is driven by the electric motor, hydraulic actuators that are driven by hydraulic fluid discharged from the hydraulic pump, and a battery device that serves as an electrical power source for the electric motor. The battery device includes battery systems that each have a plurality of batteries. A selector switch makes it possible to select either one of the battery systems. An arithmetic control section of an inverter device controls connection change switches through battery controllers to change the connections of the battery systems so that electrical power is supplied to the electric motor from either the battery system or the battery system, whichever is selected by the selector switch. | 12-05-2013 |
20140020373 | FIXED VARIABLE HYBRID SYSTEM - A fixed/variable hybrid system has modified constant flow open center hydraulic valves (“fixed/variable valves”), including an open center core, spools, a power core, and a tank galley. A small fixed displacement pump provides fluid at a constant rate to the open center core. A variable displacement piston pump provides fluid directly to the power core as needed. Activation of spools partially restricts the open center core causing an increase in fluid pressure that is communicated to the variable displacement piston pump's load sense signal port, causing the pump to increase fluid flow and pressure to the power core. Activated spools direct pressurized fluid from the power core to the applications through selected hydraulic ports. Activated spools also direct fluid flow from selected hydraulic ports via the tank galley to a hydraulic tank. Pumping the majority of fluid only on an as-needed basis results in significant efficiencies. | 01-23-2014 |
20140116041 | Walk Behind Aerator Hydrostatic Traction Drive System - A walk behind aerator hydrostatic traction drive system includes left and right rear wheel hydrostatic motors driving left and right rear wheels positioned forwardly of a coring head, and a front wheel hydrostatic motor driving a single steerable front wheel carried in a pivotal yoke. The pivotal yoke is coupled to a handle assembly attached to a neck extending upwardly and forwardly for pivoting the single steerable front wheel about a vertical pivot axis. A check valve is connected in parallel to the front wheel hydrostatic motor. The check valve opens if the walk behind aerator moves in a forward direction and the handle assembly is turned to pivot the single steerable front wheel and the front wheel rotates more than each rear wheel, or if the walk behind aerator moves in a reverse direction. | 05-01-2014 |
20140137548 | CONSTRUCTION MACHINERY - Construction machinery that can achieve a great fuel reduction effect through an efficient use of recovered energy is provided. | 05-22-2014 |
20140165548 | WORK MACHINE - A work machine includes a swing hydraulic motor and a swing electric motor for driving an upper swing structure. A capacitor supplies electricity to the swing electric motor and an operating device outputs through one operation, an operating signal for concurrently operating the swing hydraulic motor and the swing electric motor. A main controller switches between a hydraulic-alone drive mode and an electric-alone drive mode, the hydraulic-alone drive mode being a mode to drive only the swing hydraulic motor selected from the swing hydraulic motor and the swing electric motor when the operating device is operated, the electric-alone drive mode being a mode to drive only the swing electric motor selected from the swing hydraulic motor and the swing electric motor when the operating is operated. Therefore, the actuator that malfunctions can easily be specified among the plurality of mounted actuators. | 06-19-2014 |
20140208734 | WORK MACHINE - Provided is a load sensing system for controlling a discharge pressure of the hydraulic pump so as to render a differential pressure obtained by subtracting a maximum load pressure among the hydraulic actuators from a discharge pressure of the hydraulic pump to be a constant pressure, and there are provided: a first load pressure flow passage which introduces load pressures of the hydraulic actuators to be outputted to a PLS transmission line which transmits the maximum load pressure among the hydraulic actuators at the time of activating the hydraulic actuators; and a second load pressure flow passage which is a flow path for introducing the load pressures of the hydraulic actuators to be outputted to the PLS transmission line during operation after activations of the hydraulic actuators, and wherein a flow rate of the pressure oil therein is reduced than that in the first load pressure flow passage. | 07-31-2014 |
20140283510 | HYDRAULIC DRIVE SYSTEM - A shuttle valve connects a second flowpath and a drain flowpath when the hydraulic pressure in a first flowpath is greater than the hydraulic pressure in the second flowpath. The shuttle valve connects the first flowpath and the drain flowpath when the hydraulic pressure in a second flowpath is greater than the hydraulic pressure in the first flowpath. The ratio between the pressure receiving area of a first pressure section and the pressure receiving area of a second pressure section is the same as the ratio between the pressure receiving area of a first chamber side and the pressure receiving area of a second chamber side of a cylinder rod. | 09-25-2014 |
20140298789 | HYDROSTATIC TRAVEL DRIVE AND MOBILE WORKING DEVICE WITH SUCH A TRAVEL DRIVE - A hydrostatic travel drive includes a hydraulic pump that is arranged in a hydraulic circuit with two pairs of hydraulic motors. To prevent a pressure build-up between the hydraulic motors of a hydraulic motor pair on steering while stationary, a valve device is configured to set a pressure relief to a working line or to low pressure. A mobile device includes the hydrostatic travel drive. | 10-09-2014 |
20140298790 | AUTOMATIC TRANSMISSION FOR VEHICLE - A vehicle automatic transmission of a multistage type includes multiple engagement elements having an engagement state switched by an oil pressure to selectively establish a plurality of shift stages based on a combination of engagement and release of the multiple engagement elements according to an oil pressure supplied from a hydraulic circuit, each of the shift stages being established by engagement of two or more engagement elements of the multiple engagement elements, at least one of the multiple engagement elements being a normally closed engagement element engaged when no oil pressure is supplied from the hydraulic circuit, and the normally closed engagement element being a meshing engagement element. | 10-09-2014 |
20140373523 | Hydrostatic Travel Drive - A hydrostatic travel drive has a variable displacement pump, two hydraulic motors arranged in series and supplied with pressure medium in a closed hydraulic circuit by the variable displacement pump, and a flow control valve, via which a pressure medium volume flow flows from a line segment between the two hydraulic motors to a pressure sink. The flow control valve is integrated into a housing of a first of the two hydraulic motors. | 12-25-2014 |
20150020515 | DRIVE SYSTEM FOR GROUND ENGAGING MEMBER OF MACHINE - The present disclosure is related to a drive system for a ground engaging member of a machine. The drive system includes first and second hydraulic motors that are disposed parallel to each other. The drive system also include first and second brake valves that are configured to regulate flow of fluid through the first and second hydraulic motors in order to selectively perform braking. The first hydraulic motor is in fluid communication with a first input line and a first output line. The second hydraulic motor is in fluid communication with a second input line and a second output line. A first connection line is configured to fluidly communicate the first input line with the second input line to equalize pressure therebetween. A second connection line is configured to fluidly communicate the first output line with the second output line to equalize pressure therebetween. | 01-22-2015 |
20150047334 | HYDROSTATIC TRANSMISSION DEVICE ENSURING GOOD DRIVEABILITY - The present disclosure is directed to a hydrostatic transmission apparatus including a pump, a first motor, and a second motor having two elementary motors, each of them and the first motor having feed/discharge first and second enclosures. In work mode and in road mode the second enclosure of the first elementary motor of the second motor and the first enclosure of the first motor are connected together in series, the second enclosure of the first motor being connected to the second port of the pump and the second enclosure of the second elementary motor of the second motor is connected to the second port of the pump. In work mode, the first enclosure of each of the two elementary motors of the third motor is connected to the first port of the pump. | 02-19-2015 |
20150059329 | HYDRAULIC SYSTEM FOR CONSTRUCTION EQUIPMENT - A hydraulic system for a construction machine having a pressure compensation valve is disclosed, which improves operability when a combined operation of a swing device and an attachment is performed. The hydraulic system includes a hydraulic pump, attachment and swing operation devices, an attachment actuator and a swing motor connected to the hydraulic pump, a first control valve controlling hydraulic fluid being supplied to the actuator, a second control valve controlling hydraulic fluid being supplied to the swing motor, a check valve installed on a flow path for detecting load pressures of the actuator to take a maximum pressure of the load pressures, a first pressure compensation valve having an opening amount that is controlled by a difference between the maximum load sensing pressure and the pressure of a discharge flow path of the first control valve, a second pressure compensation valve having an opening amount that is controlled by a difference between the maximum load sensing pressure and the pressure of the discharge flow path of the second control valve, a maximum load pressure sensor detecting the pressure of a maximum load sensing pressure line, and a control unit controlling a discharge flow rate of the hydraulic pump, wherein the system is configured so that the swing load pressure is not connected to the first pressure compensation valve on the attachment side when a combined operation of the swing device and the attachment is performed. | 03-05-2015 |
20150075148 | HYDRAULIC CONTROL SYSTEM - A hydraulic control system is provided in which hydraulic oil discharged from a variable displacement hydraulic pump is controlled and supplied to a hydraulic actuator by a closed center control valve activated based on operation input from an operation device, thereby controlling activation of the hydraulic actuator. With the pump displacement detected by pump displacement detecting means and the pump output pressure detected by pump output pressure detecting means being used as feedback input and the characteristic value determined by the operation input and the feedback input being used as a target value of a control loop, variable displacement control is performed by a controller provided with a horsepower control loop, a pressure control loop, a flow rate control loop, and a minimum pressure holding loop that feed back a calculated value based on the feedback input or the feedback input itself. | 03-19-2015 |
20150075149 | FLEXIBLE RESPONSE SECURED MECHANICAL BALANCING FOR MULTIPLE CONTROL ACTUATORS WITH A COMMON OUTPUT - A flexible response secured mechanical balancing device (D) for multiple hydraulic control actuators ( | 03-19-2015 |
20150330415 | Hydraulic Drive System for Construction Machine - An object of the invention is to achieve a travel speed known in the art during travelling operation, improve energy efficiency by reducing energy loss, and obtain favorable travel operability less susceptible to effects from variations in a travel load and changes in a pump delivery pressure when travelling operation is performed through operation of a travel lever over a half stroke range or less. A variable restrictor valve | 11-19-2015 |
20150337869 | SELF-ORIENTING PISTON SPRING ACCUMULATOR - An accumulator for a vehicle may include a cylinder defining a bore having an inner surface, and a piston moveable within the bore. The piston may include a seal and a guide section defined by a truncated sphere. The guide section orients the piston within the bore such that the seal maintains contact with the inner surface of the bore. | 11-26-2015 |
20150368880 | HYDRAULIC CONSTRUCTION MACHINERY - Disclosed is a hydraulic construction machinery capable of operating a travel apparatus and a swing apparatus, when same are to be operated in combination, by means of working fluids supplied at the maximum discharge flow rate from a plurality of hydraulic pumps. A hydraulic construction machinery according to the present invention comprises: first and second hydraulic pumps; travel and swing motors connected to the first hydraulic pump; a hydraulic actuator connected to the second hydraulic pump; a main control valve comprising a first control valve and a second control valve, the first control valve controlling a working fluid supplied from the first hydraulic pump to the travel and swing motors, and the second control valve controlling the working fluid supplied from the second hydraulic pump to the hydraulic actuator; a first regulating valve, disposed on the most upstream side of a supply channel of the second hydraulic pump, for switching when the travel and swing motors are operated simultaneously so that the working fluid of the first hydraulic pump is supplied to the travel motor and the working fluid of the second hydraulic pump is supplied to the swing motor; a second regulating valve, disposed on the most downstream side of a supply channel of the second hydraulic pump, for switching when the travel and swing motors are operated simultaneously so as to close the most downstream opening of the supply channel of the second hydraulic pump; and an electronic proportional valve for outputting a control signal, corresponding to a control signal from a controller, to the first and second regulating valves when a manipulation signal, sensing whether the travel and swing motors are manipulated, is entered in the controller. | 12-24-2015 |
20160032565 | Driving Device for Work Machine - To provide a driving device capable of improving the operability of a plurality of single rod hydraulic cylinders. The present invention takes a construction provided with a closed circuit A in which first and third hydraulic pumps | 02-04-2016 |
20160069428 | HYDRAULIC SYSTEM FOR VEHICLE - A downsized hydraulic system for a vehicle having a mechanical oil pump and an electric oil pump is provided. The hydraulic system comprises a first check valve allowing oil to flow only from the mechanical oil pump to an oil requiring site, and a second check valve allowing oil to flow only from the electric oil pump to an oil requiring site. The first check valve comprises a first port connected to an outlet of the mechanical oil pump, a second port connected to an outlet port of the second check valve, and a third port connected to the oil requiring site. The first check valve is adapted to provide a communication among those three ports by opening the first port, and provided with a through guide allowing the oil to flow between the second port and the third port even when the first port is closed. | 03-10-2016 |
20160108938 | HYDRAULIC SYSTEM OF A VEHICLE - A hydraulic system of a vehicle is provided, said system including: a first hydraulic circuit ( | 04-21-2016 |
20160115672 | A POWER SYSTEM FOR A WORKING MACHINE - A power system for a working machine includes a transmission for driving the working machine, the transmission including a continuously variable gear box having a gear unit and a hydraulic variator unit; a work hydraulic circuit for controlling at least one hydraulic actuator of the working machine; wherein the hydraulic variator unit is hydraulically connected to the work hydraulic circuit to hydraulically transfer energy from the hydraulic variator unit to the work hydraulic circuit. | 04-28-2016 |
20160115976 | Actuator Assembly - An actuator assembly includes a first actuator and a hydraulic unit. The first actuator comprises an actuator housing, a piston in the actuator housing, and an actuator rod. The actuator assembly further includes a second actuator. The second actuator comprises an actuator housing, a piston in the actuator housing, and an actuator rod. The piston side of the first actuator faces the piston side of the second actuator and the actuator rods are coaxial. | 04-28-2016 |
20160138620 | LOAD SENSING CONTROL CIRCUIT - A pump discharge amount is divided in accordance with switch amounts of respective switch valves (V | 05-19-2016 |
20160146232 | ENERGY REGENERATION SYSTEM FOR CONSTRUCTION MACHINE - Energy regeneration system does not affect operation of a hydraulic actuator except when a relief valve is operating, by connecting an actuator hydraulic line to a regeneration hydraulic motor with a small pressure loss during regeneration, and ensures holding pressure when the energy cannot be regenerated. A first valve device disposed between actuator hydraulic lines and a regeneration hydraulic motor, has a throttle passage capable of increasing pressure in the higher pressure side actuator hydraulic line to a set pressure of the relief valves. A second valve device disposed in parallel with the first valve device between the actuator hydraulic lines and the regeneration hydraulic motor, is switched from a close to an open position by pressure between the first valve device and the regeneration hydraulic motor when pressure between the first valve device and the regeneration hydraulic motor increases to approach the set pressure of the swing relief valve. | 05-26-2016 |
20220136532 | LANDING GEAR LIFTING/LOWERING EHA SYSTEM - A landing gear lifting/lowering EHA system includes: a hydraulic actuator configured to lift and lower the leg of an aircraft; at least one electrically operated hydraulic pump; a hydraulic path; a pressure sensor attached to the hydraulic actuator or the hydraulic path and configured to output a measurement signal corresponding to hydraulic pressure; and a controller configured to output a control signal to the electrically operated hydraulic pump, wherein, when a state in which the hydraulic pressure exceeds a set pressure continues for a set time, the control unit stops the electrically operated hydraulic pump in operation and resumes the operation of the electrically operated hydraulic pump after the hydraulic pressure drops to or below a second set pressure after the electrically operated hydraulic pump is stopped. | 05-05-2022 |