Abstract: A drill rig includes a base, a drill tower coupled to and extending from the base, a drill pipe coupled to and supported by the drill tower, an air compressor coupled to the base, a prime mover coupled to the air compressor, and a fluid coupling disposed between and coupled to both the prime mover and the air compressor.

Abstract: A baler for forming a pressed bale includes a baling chamber and a press mounted within the baling chamber. The press is operable in a bale formation cycle, where the bale formation cycle includes bale formation cycle parameters. A primary power source is operably coupled with the press to transmit a power to the press, and an auxiliary power source is coupled to the press. The auxiliary power source is operable in a power transmitting mode to transmit an auxiliary power to the press. A controller is electrically coupled to the auxiliary power source such that the controller is configured for controlling operation of the auxiliary power source. The operation of the auxiliary power source is operably controlled manually or by the controller according to the bale formation cycle parameters.

Abstract: Provided are an energy regeneration device which can regenerate energy of a working fluid discharged from an actuator while controlling a flow rate of the working fluid, and a work machine including the foregoing device. The regeneration device (100) includes a boom cylinder (20), an inertial fluid container (102), an oil tank (110), an accumulator (105), a low-pressure-side opening/closing device (103), and a high-pressure-side opening/closing device (104). A calculation unit (151) calculates a duty ratio for opening/closing the low-pressure-side opening/closing device (103) and the high-pressure-side opening/closing device (104) in accordance with a desired flow rate of a working fluid discharged from the boom cylinder (20).

Abstract: A method for providing a high drivability control system for an agricultural or industrial vehicle having an engine and a continuously variable transmission (CVT) includes setting a maximum speed target (MST), and setting a vehicle speed percentage (VSP) according to input using a desired speed input. A target engine speed, a target rate of change of the engine speed, a target CVT ratio, and a target rate of change of the target CVT ratio is then calculated from the VSP, the MST, and the present engine speed. The target engine speed may be further calculated from the present vehicle speed and/or the present CVT ratio.

Abstract: A press comprises a press frame, at least one upper punch plate with at least one upper press punch held on it and/or at least one lower punch plate with at least one lower press punch held on it. A die plate has at least one receiver for powdered material to be pressed by the press punches. At least two upper drives are mechanically coupled in the operation of the press, engaging at the upper punch plate for moving the upper press punch in the vertical direction and/or at least two lower drives mechanically coupled in the operation of the press, engaging on the lower punch plate and/or the die plate for moving the lower press punch and/or the die plate in the vertical direction. A method for setting up and operating the press for producing a pellet made of the powdered material, in particular metal powder, is described.

Abstract: Provided is an electro-hydraulic drive system including first and second electro-hydraulic transmissions for driving respective wheels, the transmissions each including an electric motor, a hydraulic pump driven by the electric motor, and a hydraulic motor drive by the hydraulic pump. When used in a turf vehicle, such as a zero-turn-radius mower, the electro-hydraulic drive system operates the wheels independently from an engine of the mower, thereby allowing the mower to be moved without having to start the engine. In this way, power consumption is lowered and total efficiency of the mower is increased.

Abstract: A construction machine including: a swivel motor; a working attachment having a boom, a boom cylinder, an arm and an arm cylinder; a hydraulic actuator circuit having a first circuit including the boom cylinder and a boom control valve, a second circuit including the arm cylinder and an arm control valve, and a third circuit including the swivel motor and a swivel control valve; first to third pumps for the first to third circuits; a merge valve having a first position for merge of third pump fluid into the first circuit and connection of an unload line of the third circuit to a tank, and a second position for prohibiting the merge; and a merge selecting control section which holds the merge valve at the first position either of when only a swivel operation is performed and when a boom raising operation is performed.

Abstract: Provided is an electro-hydraulic drive system including first and second electro-hydraulic transmissions for driving respective wheels, the transmissions each including an electric motor, a hydraulic pump driven by the electric motor, and a hydraulic motor drive by the hydraulic pump. When used in a turf vehicle, such as a zero-turn-radius mower, the electro-hydraulic drive system operates the wheels independently from an engine of the mower, thereby allowing the mower to be moved without having to start the engine. In this way, power consumption is lowered and total efficiency of the mower is increased.

Abstract: A high-temperature butterfly valve (100) is provided. The high-temperature butterfly valve (100) includes a valve assembly (110), a valve actuator (123) configured to couple to the valve assembly (110), with the valve actuator (123) including an actuator shaft (126) configured to couple to a valve shaft (121) of the valve assembly (110), and a fluid cooling system (225) configured to flow a cooling fluid through at least a portion of the valve actuator (123).

Abstract: Provided is an abnormality detecting device for a construction machine that can estimate an abnormality occurring to a component (engine, pump, etc.) of the construction machine based on the relationship among a plurality of pieces of sensor information and thereby prevent machine failure. A correlation coefficient calculation unit 102 calculates correlation coefficients between time-series sensor values acquired by a plurality of sensors 101. A correlation coefficient comparison unit 103 compares the correlation coefficients and calculates the degree of difference between each correlation coefficient and other correlation coefficients. An abnormality judgment unit 104 judges that an abnormality has occurred to a part related to a sensor when the degree of difference calculated in regard to the sensor exceeds a preset value.

Abstract: A hydraulic system includes a pump (22) that draws fluid from a reservoir (24) and an actuator (26) having a first port and a second port. A metering valve arrangement (28) controls fluid flow through the actuator and includes a meter-in valve (30a, 30d) positioned between the pump and the first port and a meter-out valve (30b, 30c) positioned between the second port and the reservoir. A controller (34) controls operation of the metering valve arrangement. In a meter-in mode, the controller controls a fluid flow rate through the actuator by controlling an orifice size of the meter-in valve. In a meter-out mode, the controller controls a fluid flow rate through the actuator by controlling an orifice size of the meter-out valve. The controller determines the fluid flow rate through the actuator based on data derived from the meter-out valve in both the meter-in mode and the meter-out mode.

Abstract: An engine control system for a construction machine is disclosed, which can compulsorily stop engine driving when an attachment or the like malfunctions against an operator's intention during the operation of an excavator or the like. The engine control system includes a first step of determining whether pilot signal pressure, which is detected when at least one of an operation lever and a traveling pedal for respectively operating an attachment, a swing device, and a traveling device is operated, exceeds a first set pressure, and a second step of determining whether the pressure on the outlet side of a main hydraulic pump exceeds a second set pressure, wherein if the pilot signal pressure detected in the first step does not exceed the first pressure and the pressure of the main hydraulic pump detected in the second step exceeds the second pressure, engine driving is compulsorily stopped by means of a control signal from the controller.

Abstract: An electric power accumulating means (30) includes a DC bus connected to an electric power accumulator (19) and supplies a direct current, a smoothing capacitor provided to the DC bus, and a voltage detector (23) that detects a voltage of the DC bus. The generator (12) generates an induced voltage E by being rotationally driven by an engine (11) when starting the engine (11). Degaussing of a permanent magnet of the generator is determined by performing a comparison between the induced voltage E detected by the voltage detector (23) and a previously set reference induced voltage RE.

Abstract: A system for detecting a type of hydraulic device. The system includes a hydraulic device. The system also includes a power supply having an engine and a controller. The controller is configured to detect a voltage of a signal from the hydraulic device, to categorize the signal as a type of signal of multiple types of signals based on the voltage, and to control a hydraulic output based on the voltage and the type of the signal.

Abstract: A drive system suppresses cylinder speed fluctuation at times of load inversion in a hydraulic closed circuit system in which a single rod cylinder is driven by a hydraulic pump. The drive system has a control device including: pressure detection means which detect pressure in a rod-side hydraulic chamber of the hydraulic cylinder and pressure in a head-side hydraulic chamber of the hydraulic cylinder; load calculation means which calculates the load on the hydraulic cylinder from the pressure in the rod-side hydraulic chamber and the pressure in the head-side hydraulic chamber; load switching means which calculates a first proportional gain in accordance with the polarity of the calculated load; and multiplication means which calculates a command signal by multiplying the calculated first proportional gain and an operation amount input from the operating device together and outputs the calculated command signal to the delivery flow rate control means.

Abstract: One embodiment of the system comprises a towable machine having at least one hydraulic motor arranged on the machine and operable to drive at least one wheel arranged on the machine. At least one hydraulic propelling pump is arranged to supply hydraulic fluid flow via a hydraulic circuit to the hydraulic motor to selectively drive the wheel. The system has a non-operative configuration wherein hydraulic fluid flow is blocked between the hydraulic motor and the hydraulic pump. A pressure sensor is associated with the hydraulic circuit to detect an improper pressure load when the circuit is in a non-operative configuration, and operates to trigger an alarm element.

Abstract: A hydraulic motor (52) is arranged in a control hydraulic line (51) connecting a second hydraulic fluid supply line (4a) (for supplying the hydraulic fluid delivered from the main pump (2) to flow control valves (26a to 26h)) to a tank (T). A generator (53) connected with the rotating shaft (52a) of the hydraulic motor (52). Maximum load pressure (PLmax) is detected by a pressure sensor (54). Power generation control of the generator (53) is performed by a second control device (55) so that the hydraulic motor (52) rotates when the delivery pressure of the main pump (2) exceeds target control pressure (Pun) determined by adding a preset value (Pb) to the maximum load pressure (PLmax). AC power generated by the generator (53) is stored in a battery (41).

Abstract: A sensor assembly for use with a master cylinder is described. The master cylinder comprises an input-side activation element to which a signal transmitter element is coupled. The sensor module comprises a travel sensor for sensing travel carried out by the activation element, and a position sensor for sensing when a predefined position of the activation element is reached.

Abstract: Methods and systems for indicating brake booster degradation when braking is suspended may include comparing expected brake booster vacuum with measured brake booster vacuum, and indicating a fault when the difference between the two values exceeds a threshold. In one example, the expected brake booster vacuum is computed differently depending on whether intake manifold vacuum or vacuum from one or more vacuum-powered pumps dominates evacuation of the brake booster. Expected brake booster vacuum may be computed based on expected brake booster mass air flow and brake booster volume; when measured brake booster vacuum is less than intake manifold vacuum, expected brake booster mass air flow may be computed as a function of intake manifold vacuum and measured brake booster vacuum, whereas expected brake booster mass air flow may be computed based on flow characteristics of the pump(s) when measured brake booster vacuum is not less than intake manifold vacuum.

Abstract: A lift truck includes systems and methods for improved stability control. Stability control features reduce or eliminate motion of the truck in one or more of the X-axis, Y-axis, and Z-axis. Some embodiments may include, alone or in combination with the stability control, vibration control to further stabilize the motion of the truck.

Abstract: A hydrostatic transmission apparatus for a vehicle having at least two wheels, the second wheel being steerable, may include a main hydraulic pump, two hydraulic motors driving respective ones of the wheels, detection means for detecting that the second wheel is turned by being steered, a first synchronization duct between the first and second motors, and re-feed means for re-feeding the first synchronization duct, and suitable for acting, while the second motor is being fed by the first motor via the first synchronization duct, and when the second wheel is turned by being steered, to inject fluid into the first synchronization duct while limiting the pressure in said synchronization duct to a pressure less than a re-feed pressure that is significantly less than the high pressure of the pump.

Abstract: A power system for a vehicle includes a hydraulic pressure generating device, a first hydraulically operated device, a second hydraulically operated device, a common oil channel, a first bifurcated oil channel, a second bifurcated oil channel, and an oil state detector. The first hydraulically operated device is configured to be operated by liquid supplied from the hydraulic pressure generating device. The second hydraulically operated device is configured to be operated by liquid supplied from the hydraulic pressure generating device. The common oil channel is connected to the hydraulic pressure generating device. The first bifurcated oil channel connects the common oil channel and the first hydraulically operated device. The second bifurcated oil channel connects the common oil channel and the second hydraulically operated device. The oil state detector is provided in the common oil channel and configured to detect the state of the liquid.

Abstract: A closed loop hydraulic system includes a hydraulic tank, a hydraulic power source, and an air pump. The hydraulic power source is in fluidly coupled to the hydraulic tank to draw the hydraulic fluid from the hydraulic tank. The air pump is in fluid communication with an air space in the hydraulic tank to pressurize the hydraulic tank. Further, a controller configured to receive a pressure signal from a pressure sensor associated with the hydraulic tank and regulate the hydraulic power source and the air pump based on the pressure signal.

Abstract: Generally, example systems and methods for measuring aeration level of a liquid may involve measuring the pressure at two points in the liquid reservoir. The aeration level of the liquid in the liquid reservoir may be calculated based on the pressure differential between the two points in the liquid reservoir. Optionally, the aeration level of the liquid may be compared to a threshold value of the liquid aeration level, and a machine action may be commanded if the aeration level exceeds the threshold value. Example machine actions may include warning the operator. In addition, data relating to the level of aeration of the liquid may be stored, along with other machine parameters, and the data correlated for analysis and machine diagnostics.

Abstract: A mechanical seal support system includes a bladder accumulator and a device for generating an electrical signal responsive to the temperature and pressure within the bladder accumulator and for generating an electrical signal indicative of the volume of a liquid in the accumulator. A display device receives the signal and provides a visual indication of the volume of the liquid.

Abstract: A method and apparatus for clean energy generation by means of Pressure Retarded Osmosis (PRO) in closed circuit by a batch process or by a consecutive sequential process comprises two sections; one of a disengaged Side Conduit (SC) undergoing replacement of High Salinity Diluted Concentrates (HSDC) by fresh High Salinity Feed (HSF); and the other of a close circuit system with 3 modules connected in parallel wherein Low salinity feed (LSF) is continuously supplied and whereas part of the HSDC is being recycled through said modules and the other part used for power generation by means of a fixed speed turbine (T) and 3 rated generators (G1, G2 and G3) which are actuated simultaneously or separately as function the power availability during the PRO process. Periodic engagement of said SC with HSF and the closed circuit enable replacement of pressurized HSDC by fresh HSF without stopping the power generation process.

Abstract: Disclosed is a hydraulic circuit for a pipe layer, in which the generation of hydraulic shock in equipment is prevented when an operating device or a moving device is finely operated during combined work in a pipe-laying operation mode.

Abstract: A system and method for predicting impending pump failure in a hydraulic system is disclosed. The system measures and compares the running and moving volumetric deficiencies of the hydraulic system as a whole and if they are not within range of each other by a predetermined threshold, the system determines that at least one of the pumps in the system is about to fail. If such a determination is made by the system, the pump displacement is at standby of each pump is then calculated and the pump with the greatest displacement at standby is determined to be the pump approaching failure. Once the pump approaching failure is identified, a signal is generated to apprise the operator or other entity to enable corrective action to be taken.

Abstract: In one aspect, a hydraulic system including a reservoir, a hydraulic device, a first sensor, a second sensor and a controller is described. The reservoir is connected to the hydraulic device for supplying hydraulic fluid to and from the hydraulic device. The first sensor is adapted for measuring a first volume of the hydraulic fluid in the reservoir. The second sensor is connected to the hydraulic device such that at least one parameter being indicative for a second volume of the hydraulic fluid in the hydraulic device is measurable. The controller is adapted for calculating the second volume of the hydraulic fluid based on the at least one parameter. The controller is adapted for determining a leakage of hydraulic fluid in the hydraulic system based on the first volume and the second volume.

Abstract: A system and method for controlling an accumulator for use with a hydraulic circuit is provided. The system and method is configured to determine a set of accumulator temperature indicators and discharge and charge the accumulator as a function of the set of accumulator temperature indicators.

Abstract: A system and method for controlling the movement of an implement of an earthmoving machine. The system includes a hydraulic actuator adapted to move the implement. A variable displacement pump is coupled to the actuator for delivering a pressurized fluid to and receiving pressurized fluid from chambers within the actuator. A sensor generates an output based on the position of the actuator's piston or piston rod, and a controller controls the displacement of the variable displacement pump in response to the output of the sensor by executing an algorithm to reduce the flow rate of the fluid to and from the actuator's chambers and thereby reduce the velocity of the piston as it approaches an end of a piston stroke thereof and prevent the piston from impacting the actuator at the end of the piston stroke.

Abstract: 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.

Abstract: A hydraulic pump control system provided in a construction machine such as an excavator is provided. According to the hydraulic pump control system, a loss of a flow rate is reduced by initially supplying hydraulic fluid as much as necessary from a hydraulic pump to a hydraulic motor in order to accelerate a swing movement of an upper frame against a lower traveling structure or to make an upper swing structure swing.

Abstract: A hydraulic circuit system for a hydraulic excavator, which has a hydraulic circuit for an attachment, includes: a directional control valve 16 that supplies a hydraulic fluid to an attachment connected to the hydraulic circuit for an attachment; a first over-load relief valve unit 38 that is provided in one of lines of the hydraulic circuit for an attachment; a second over-load relief valve unit 39 that is provided in the other of the lines of the hydraulic circuit for an attachment; a first proportional solenoid valve 40 that controls set relief pressure of the first over-load relief valve unit 38; and a second proportional solenoid valve 41 that controls set relief pressure of the second over-load relief valve unit 39. The attachment having various characteristics and capacity, such as a hydraulic breaker or a crusher, can be applied to the hydraulic circuit for an attachment in a simple configuration.

Abstract: A fluid circuit includes a tank for holding fluid, a hydraulic device having a predetermined load configuration, and a pump for delivering the fluid under pressure to the hydraulic device. Sensors measure at least one of a supply pressure, a tank pressure, and a position of a portion of the hydraulic device. A controller estimates or reconstructs an output value of any one sensor using the predetermined load configuration in the event of a predetermined failure of that sensor, ensuring continued operation of the hydraulic device. A method for estimating the output value includes sensing output values using the sensors, processing the output values using the controller to determine the presence of a failed sensor, and calculating an estimated output value of the failed sensor using the predetermined load configuration. Operation of the hydraulic device is maintained using the estimated output value until the failed sensor can be repaired.

Abstract: A hydraulic arrangement includes at least one pressure unit connected to a hydraulic machine that is operable as a pump and a safety device for the pressure unit. The safety device includes pressure sensors configured to detect a pressure in the pressure unit and an electronic control unit that is connected to the pressure sensors. A delivery volume pumped by the hydraulic machine is configured to be controlled via the control unit.

Abstract: A working vehicle with an HST in which over-rotation of a hydraulic pump in the HST or the pump input shaft thereof is prevented when a main clutch is disconnected during a run. When a main clutch connection/disconnection detection means detects the disconnection state of the main clutch during a run, a control means judges whether a vehicle speed detected by a vehicle speed detection means is at least a set speed or not, and if the vehicle speed is at least the set speed, the movable swash plate of the hydraulic pump in an HST is controlled to sustain it at the current inclination angle.

Abstract: A hydraulic control system is disclosed. The hydraulic control system may have a hydraulic actuator, a valve arrangement, and an operator input device configured to generate a first signal indicative of a desired hydraulic actuator velocity. The hydraulic control system may also have a sensor configured to generate a second signal indicative of an actual flow rate of fluid entering the hydraulic actuator, and a controller. The controller may be configured to determine a desired flow rate of fluid into the hydraulic actuator based on the first signal; to estimate the actual flow rate based on the desired flow rate, a correction flow rate, and a system response model; and to determine the actual flow rate based on the second signal. The controller may also be configured to make a comparison of the estimated and determined actual flow rates of fluid, and to determine the correction flow rate based on the comparison.

Abstract: A method of detecting a fluid leak in a hydraulic fluid circuit includes preventing fluid from entering the circuit when an actual outlet flow rate from a pump is positive while a requested outlet flow rate to a hydraulic machine is zero. An outlet port of a variable displacement port can be selectively blocked, while in a fixed displacement pump (FDP) fluid can be diverted from the outlet port to a secondary fluid circuit. The actual outlet flow rate can be measured using a flow sensor or a swash plate angle depending on the pump design. A hydraulic fluid circuit includes a hydraulic machine, a pump, a valve at an outlet port of the pump, and a controller. The controller determines the requested flow rate, and actuates the valve to prevent fluid from entering the circuit whenever the actual outlet flow rate is positive during zero requested flow rate.

Abstract: A method of detecting the braking of a vehicle comprising a push rod (200) intended to transmit an amplified braking command to a master cylinder. A plunger (220), arranged parallel to the primary piston (200) so as to reproduce the movements of this piston, and a sensor (230) which senses the movements of the plunger (220), this sensor (230) being fastened to the booster (250), are used to detect a braking operation by detecting a movement of the plunger (220).

Abstract: A system for moving an object in one axis that creates highly dispersed but precisely controlled mechanical force to support, manipulate, and maintain an object, tool or application in precise alignment or orientation with respect to a stationary or moving target is disclosed. The system includes one or more fluid containers within a cylindrical enclosure or drum, and a shaft running through longitudinal axis of the drum. The shaft is coupled to the drum by rotating assemblies so that the drum may rotate around the shaft or the draft may rotate inside the drum. The fluid inflatable containers are arranged in a inside the drum around the shaft so that each container exerts expansive force between a vane fixed to the drum and a vane fixed to the shaft. A volume of the fluid may be placed in the one or more fluid containers by control systems. By changing the volume of fluid in the one or more containers, forces are exerted on the vanes and the object is moved.

Abstract: One embodiment of the system comprises a towable machine having at least one hydraulic motor arranged on the machine and operable to drive at least one wheel arranged on the machine. At least one hydraulic propelling pump is arranged to supply hydraulic fluid flow via a hydraulic circuit to the hydraulic motor to selectively drive the wheel. The system has a non-operative configuration wherein hydraulic fluid flow is blocked between the hydraulic motor and the hydraulic pump. A pressure sensor is associated with the hydraulic circuit to detect an improper pressure load when the circuit is in a non-operative configuration, and operates to trigger an alarm element.

Abstract: A hydraulic aggregate for supplying a hydraulic cylinder in consecutive load strokes is monitored for its working load in order to determine the condition of the aggregate automatically. For this purpose, the time integral of the pressure is determined for each load stroke. The pressure and duration are processed into a characteristic number which indicates the wear. This makes it possible to diagnose the condition of the hydraulic aggregate at any time.

Abstract: In a relief pressure switching apparatus for hydraulic working machine for switching a relief pressure of a hydraulic actuator circuit in accordance with a specification of a compression crushing apparatus or a breaker to be installed, electromagnetically variable relief valves for determining the relief pressure are provided, and a controller commands the relief pressure selected by an operator from a plurality of relief pressures preliminarily set and stored in combination with a flow rate as matching a working apparatus to the relief valves.

Abstract: A load sensing system includes a first assembly of actuators for controlling a first hydraulic function, a pump adapted to supply the actuators with pressurized hydraulic fluid, an electrically controlled valve adapted to control the output pressure of the pump via a hydraulic signal, a first pressure sensor for detecting a load pressure of the first actuator assembly, and a control unit adapted to receive a signal with information about the load pressure detected by the first pressure sensor and to generate a control signal, corresponding to the detected load pressure, to the electrically controlled valve.

Abstract: A fluidic actuator and a control system for the fluidic actuator are described. A first component of the actuator may have two openings interconnected by a passageway. A second component may be moveably housed within the passageway and divide the passageway into two portions. A fluid delivery system may be connected to the two openings. The fluid delivery system may supply a first pressure of fluid to the first portion of the passageway causing the second component to move within the passageway at a first speed. When the second component is in a selected position within the passageway, the fluid delivery system may reduce the pressure of the fluid, causing a reduction in speed of the second component. The fluidic actuator may be used in a wafer processing system.

Abstract: When a hydraulic pressure generation source begins to generate hydraulic pressure, the present invention measures the hydraulic pressure in an oil supply line connected to a hydraulic actuator, and sets a viscosity index value indicating an oil viscosity in accordance with the pace at which the measured hydraulic pressure rises. The viscosity index value is calculated and set so that the slower the pace at which the measured hydraulic pressure rises, the higher the viscosity indicated by the viscosity index value.

Abstract: A method and apparatus are provided for hydraulic fluid supply between a hydraulic pump and a hydraulic drive unit, switching hydraulic fluid flow direction to the hydraulic drive unit or stopping hydraulic fluid flow to the hydraulic drive unit when measured hydraulic fluid pressure crosses a predetermined pressure threshold value. The method further comprises calculating an amount of mechanical work done by the hydraulic drive unit and warning an operator or limiting hydraulic fluid flow rate to the hydraulic drive unit when the calculated mechanical work for the drive cycle is less than an expected amount of mechanical work. The apparatus for practicing the method further includes a pressure sensor associated with a hydraulic fluid supply conduit between the pump and the drive unit, and an electronic controller programmed to operate the drive system according to the method.

Abstract: A working vehicle with an HST in which over-rotation of a hydraulic pump in the HST or the pump input shaft thereof is prevented when a main clutch is disconnected during a run. When a main clutch connection/disconnection detection means (112) detects (S2) the disconnection state of the main clutch (22) during a run, a control means (110) judges (S3) whether a vehicle speed detected by a vehicle speed detection means (116) is at least a set speed or not, and if the vehicle speed is at least the set speed, the movable swash plate (55) of the hydraulic pump (51) in an HST (50) is controlled to sustain it at the current inclination angle (S4).

Abstract: The invention concerns a hydraulic system for moving automatic closing apparatuses, comprising hydraulic actuating means capable to move at least one movable member coupled to at least one closing apparatus, wherein said hydraulic actuating means is operated by at least one low voltage dc motor. Preferably, the electronic unit controls, through an encoder and microswitches, the position of a piston or a rotating shaft that operates the automatic closing apparatus during closing and opening phase, favouring an automatic learning of operation times.