Abstract: The present invention provides a cooling system such as employed in cooling a heat source and a transmission system having said cooling system integrated therewith. The cooling system further includes a pump for supplying hydraulic fluid under pressure to a motor for driving a fan employed in the cooling process. In operation, a controller initiates operation of the pump such as to supply hydraulic fluid to said motor only when needed, thereby to improve the efficiency and controllability of the cooling system.

Abstract: A hydraulic motor having a cooling system includes a stator, a rotor that rotates and orbits in the stator, a drive link connected to the rotor, and a housing connected with the stator. The housing includes a working fluid inlet port, a working fluid outlet port, a cooling fluid inlet port, and a cooling fluid outlet port. Each port extends through the housing and is configured to connect with a different associated external fluid line. Pressurized fluid enters the working fluid inlet port to rotate and orbit the rotor en route to the working fluid outlet port. The cooling fluid ports are isolated from the working fluid inlet port and the working fluid outlet port within the housing.

Abstract: A machine includes a hydraulic cylinder configured to raise and lower a boom of the machine, and an accumulator selectively fluidly connected to the hydraulic cylinder. The accumulator is configured to receive fluid from the hydraulic cylinder during lowering of the boom. The machine also includes a hydraulic motor fluidly connected to the accumulator via an independent metering valve. The machine further includes a fan driven by the hydraulic motor and configured to assist in cooling fluid displaced from the hydraulic cylinder.

Abstract: An oil supply device for a vehicle includes an oil pump driven by a rotation of an internal combustion engine, a hydraulic actuator to which oil is supplied from the oil pump, an engine lubricating system to which the oil is supplied from the oil pump, an oil supply adjusting valve adjusting a supply condition of the oil from the oil pump to the hydraulic actuator and the engine lubricating system, a first oil supply passage supplying the oil from the oil pump to the hydraulic actuator, and a second oil supply passage supplying the oil from the oil pump to the engine lubricating system, wherein the oil supply adjusting valve consistently distributes the oil to the first oil supply passage and the second oil supply passage.

Abstract: A power generating apparatus includes a rotating shaft, a hydraulic pump driven by the rotating shaft, a hydraulic motor driven by operating oil supplied from the hydraulic pump; and a generator coupled to the hydraulic motor. The apparatus further includes an oil line connected to the hydraulic pump and the hydraulic motor for circulating the operating oil between the hydraulic pump and the hydraulic motor, an oil cooler connected to the oil line for cooling the operating oil by heat exchange with a cooling medium, a cooling-medium line supplying the cooling medium to the oil cooler; a bypass line diverging from at least one of the oil line and the cooling-medium line and merging into at least one of the oil line and the cooling-medium line to bypass the oil cooler; and a flow regulating valve in at least one of the oil line and the cooling-medium line.

Abstract: Multistage hydraulic systems and methods for converting the potential energy of a pressurized gas, particularly air, into mechanical work when operating in motor, and for producing compressed gas from the mechanical work of the rotating shaft when rotating when operating in compressor mode, by performing a successive expansion/compression of the said gas. Each of the systems comprises: a multistage Compression-Expansion Unit made of several hydraulic Compression-Expansion Modules having different capacity and integrating a gas/liquid separating heat exchanger, designed to convert pressure power into a hydraulic power and vice-versa, by performing an essentially isothermal compression/expansion of the gas; a single stage or multistage, direct or indirect, external forced-air Heat Exchanger for maintaining the active liquid at ambient temperature; and a multi-circuit, multi-displacement Hydraulic Motor/Pump for converting hydraulic power into mechanical power and vice-versa.

Abstract: A pressure reducing gas storage device, an air-jet system and a motor vehicle are disclosed herein, wherein the pressure reducing gas storage device comprises a gas storage tank including an inlet for receiving compressed air and an outlet for outputting air and a heat exchanger for heating the air in the air input into the gas storage tank. By providing a heat exchanger to heat the air input in the gas storage tank, the phenomenon of being frozen is eliminated and the pressure reducing gas storage device is able to work continuously and stably.

Abstract: A dump truck includes: an oil-cooling center brake; a first hydraulic pump supplying cooling oil to the center brake; a second hydraulic pump supplying cooling oil to the center brake in addition to the cooling oil from the first hydraulic pump; a hydraulic motor driving the second hydraulic pump; a third hydraulic pump supplying hydraulic oil to the hydraulic motor; an open/close valve letting the hydraulic oil bypass the hydraulic motor; and a controller controlling a bypass flow amount at the open/close valve. A capacity of the first hydraulic pump corresponds to a flow amount of the cooling oil required to lubricate a transmission. A capacity of the second hydraulic pump corresponds to a flow amount for compensating the cooling oil from the first hydraulic pump when a brake is off. A capacity of the third hydraulic pump is smaller than the capacity of the second hydraulic pump.

Abstract: The invention relates to a system for regulating a temperature of hydraulic fluid in at least one hydraulic circuit of an aircraft, wherein, in a periphery of the aircraft, additional hydraulic consumption units are each provided with at least one controllable valve for heating the hydraulic fluid above an adjustable minimum temperature limit value (Tmin), wherein the controllable valve is closed during a maneuver of the aircraft, wherein the controllable valves of the additional hydraulic consumption units are closed when the temperature of the hydraulic fluid exceeds an adjustable theoretical temperature value (Tsoll), and wherein a temperature control system is connected to a temperature sensor for adjusting the controllable valve on the basis of a local temperature of the hydraulic fluid, the temperature sensor being near the hydraulic consumption units which are arranged in wings and tail of the aircraft.

Abstract: A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.

Abstract: There are provided: an HST hydraulic circuit that is formed through a closed circuit connection of a variable displacement hydraulic pump 2 and first and second variable displacement hydraulic motors 3 and 4; a charge pump 6 that replenishes the HST hydraulic circuit with hydraulic oil; a cooling circuit through which an excess of the hydraulic oil that has been replenished from the charge pump 6 to the HST hydraulic circuit is returned to a reservoir through the hydraulic pump 2, the first hydraulic motor 3, and the second hydraulic motor 4; a hydraulic source 7 that supplies hydraulic oil to an hydraulic device other than the first and second hydraulic motors; and a merge circuit through which a portion of hydraulic oil from the hydraulic source 7 is merged into an intermediate oil line 22 that lies downstream of the first hydraulic motor 3 and upstream of the second hydraulic motor 4 in the cooling circuit.

Abstract: A construction machine includes an engine, a hydraulic pump driven by drive force of the engine, a generator motor, and a dipstick tube. The generator motor is disposed between the engine and the hydraulic pump. The generator motor has a rotary shaft connected to an input shaft of the hydraulic pump and to an output shaft of the engine and an oil pan disposed in a lower part of a holding space formed inside a housing. The dipstick tube has a connector provided at a location that communicates with the oil pan of the generator motor, and a dipstick opening disposed above the generator motor, for checking a level of oil in the oil pan.

Abstract: A hydraulic control system includes a source of pressurized hydraulic fluid for providing a pressurized hydraulic fluid, a main line circuit in fluid communication with the source of pressurized hydraulic fluid, a regulation valve in communication with the source of pressurized hydraulic fluid, the regulation valve moveable between a plurality of positions, and a lubrication valve in communication with the regulation valve, the lubrication valve moveable between a plurality of positions. A lubrication circuit and a cooling circuit are in communication with the lubrication valve.

Abstract: The invention relates to a fluid cooling device (1) as a structural unit having a drive motor (2) which drives a rotatable fan impeller (3), and having a storage tank (4) which has a filling opening (6) as well as a fill-level indicator (7) and from which at least one fluid can be conveyed into a hydraulic working circuit, wherein in the hydraulic working circuit the fluid is heated and is cooled via a heat exchanger (5) of the structural unit, and preferably returned into the storage tank (4). The invention is characterised in that the structural unit is designed as a turning assembly in which the filling opening (6) for fluid and the fill-level indicator (7) are disposed on the storage tank (4) in such a way that they can be used and Mad in the case of a first, preferably vertical installation direction (X, Y) of the structural unit, and in the case of a second installation direction (Y, X) which is inclined with respect to the fast installation direction (X, Y), preferably at right angles thereto.

Abstract: Systems, methods and devices for optimizing thermal efficiency within a gas compression system are described herein. In some embodiments, a device can include a first hydraulic cylinder, a second hydraulic cylinder, and a hydraulic actuator. The first hydraulic cylinder has a first working piston disposed therein for reciprocating movement in the first hydraulic cylinder and which divides the first hydraulic cylinder into a first hydraulic chamber and a second hydraulic chamber. The second hydraulic cylinder has a second working piston disposed therein for reciprocating movement in the second hydraulic cylinder and which divides the second hydraulic cylinder into a third hydraulic chamber and a fourth hydraulic chamber. The hydraulic actuator can be coupled to the first or second working piston, and is operable to move the first and second working pistons in a first direction and a second direction such that volume in the hydraulic chambers are reduced accordingly.

Abstract: A lubrication system is provided that includes a pump operatively connected to one or more supply lines for delivery of a lubricant, the system including a first pressure sensor associated with the supply line at a first position, and a second pressure sensor associated with the supply line at a second position downstream of the first position and pump, a controller configured to receive pressure signals and control operation of the pump based upon the pressure differential between the pressures at the first position and second position. The pressure differential may be employed to determine when a pressure at a third position downstream of the second position has been achieved. At least one of the pressure sensors may be positioned adjacent to the pump, the controller further being operable to deactivate the pump in the event that a maximum pump pressure has been met.

Abstract: An improved vacuum material handler having an onboard drive engine powering a vacuum pump and a hydraulic pump. The vacuum material handler also having a frame with integrated forklift lugs.

Abstract: A hydraulic fluid cooling system for a pair of integrated hydrostatic transmissions includes a common reservoir holding hydraulic fluid and having hydraulic lines connecting the common reservoir to each integrated hydrostatic transmission, a hydraulic fluid reservoir inside each integrated hydrostatic transmission, and a pump for pumping fluid from each transmission's hydraulic fluid reservoir to the other transmission. Hydraulic fluid lines link each transmission's hydraulic fluid reservoir to the other transmission. The system pumps hydraulic fluid from the sump or reservoir of each integrated hydrostatic transmission to the other transmission, providing the cooling capacity of a non-loaded transmission to cool hydraulic fluid for a fully loaded transmission.

Abstract: A hydraulic motor having a cooling system includes a stator, a rotor that rotates and orbits in the stator, a drive link connected to the rotor, and a housing connected with the stator. The housing includes a working fluid inlet port, a working fluid outlet port, a cooling fluid inlet port, and a cooling fluid outlet port. Each port extends through the housing and is configured to connect with a different associated external fluid line. Pressurized fluid enters the working fluid inlet port to rotate and orbit the rotor en route to the working fluid outlet port. The cooling fluid ports are isolated from the working fluid inlet port and the working fluid outlet port within the housing.

Abstract: Systems, methods and devices for optimizing thermal efficiency within a gas compression system are described herein. In some embodiments, a device can include a first hydraulic cylinder, a second hydraulic cylinder, and a hydraulic actuator. The first hydraulic cylinder has a first working piston disposed therein for reciprocating movement in the first hydraulic cylinder and which divides the first hydraulic cylinder into a first hydraulic chamber and a second hydraulic chamber. The second hydraulic cylinder has a second working piston disposed therein for reciprocating movement in the second hydraulic cylinder and which divides the second hydraulic cylinder into a third hydraulic chamber and a fourth hydraulic chamber. The hydraulic actuator can be coupled to the first or second working piston, and is operable to move the first and second working pistons in a first direction and a second direction such that volume in the hydraulic chambers are reduced accordingly.

Abstract: A turbojet for an aircraft includes an engine housed in a nacelle and a thermal exchanger that can be traversed by a hot fluid designed to be cooled by thermal exchange with a cold fluid external to the thermal exchanger. The thermal exchanger is disposed in an internal volume of the nacelle, between an internal wall of the nacelle and an external wall of the engine, in such a way as to present two thermal exchange surfaces in the flow of the air stream from the turbojet. The disclosed embodiments also relate to an aircraft equipped with such a jet turbine engine.

Abstract: The housing of a vane-type machine has a largely cylindrical space for accommodating the vane cells. A shaft is eccentrically arranged in the housing. First and second guide plates are provided on the shaft. Slides displaceable largely radially to the shaft in the direction of the inner housing wall are guided by the guide plates. A vane cell is formed with the participation of two adjacent slides of the adjacent region of the inner housing wall and the volume of the vane cells in the region of an inlet opening differs from the volume of the vane cells in the region of an outlet opening. To increase the speed of the shaft and the temperature of the medium, the slides are lubricated by pressure oil and radially and axially guided by a guideway, which is fixed with respect to the housing.

Abstract: An axle driving apparatus includes a first housing having a plurality of cooling fins, an axle rotatably mounted in the first housing, a hydraulic stepless speed change assembly disposed within the first housing. The axle driving apparatus also includes a second housing having a plurality of cooling fins, an axle rotatably mounted in the second housing, a hydraulic stepless speed change assembly disposed within the second housing. A connecting means, such as a bar and/or plate connects the first and second housings. The plurality of cooling fins on the first housing has a different configuration that the plurality of cooling fins on the second housing.

Abstract: The invention relates to a hydraulic group comprising a reservoir (28) for oil, in which a multiple piston pump (60) is arranged. The individual pumps (61) are cyclically driven by an eccentric ring (29). In order to ensure a permanent immersion of the individual pumps in the reservoir (28), an auxiliary reservoir (47) providing oil for refilling the reservoir (28) is arranged above the reservoir. The auxiliary reservoir (47) is connected to an additional tank (45) by means of a connection line (48).

Abstract: A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.

Abstract: A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.

Abstract: A system and method for variator control employs positively directed electronic make-up and flushing relief valves for more precise torque control of a hydraulic variator, especially during torque reversal, as well as improved cold weather operation. This can improve machine response during periods of severe torque change. The ability to more tightly control variator torque allows more precise torque management algorithms for power control and engine matching purposes. Moreover, the ability to positively control venting of the hydraulic circuit for purposes of fluid cooling allows for more consistent machine response regardless of ambient temperature.

Abstract: A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.

Abstract: A hydraulic system for controlling a belt-driven conical-pulley transmission. A pump draws a working medium from a working medium tank or through a cooler return valve from a cooler return line. The cooler return valve is a minimum pressure valve that holds closed a connection between the cooler return line and a pump inlet line through the cooler return valve, as long as the pressure in the cooler return line remains below a specified minimum pressure. The cooler return valve also opens the connection between the cooler return line and the pump inlet line through the cooler return valve as soon as the specified minimum pressure in the cooler return line is exceeded.

Abstract: A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.

Abstract: A hydrostatic transmission having a hydraulic pump that is fluidly connected to a hydraulic motor. The transmission also has a pressure control valve that has first and second stages and is fluidly connected to the hydraulic pump. By utilizing the pressure control valve when the first stage of the pressure control is at a minimum pressure the second stage determines the minimum charge pressure setting for the hydrostatic transmission.

Abstract: A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.

Abstract: A pump control apparatus for a hydraulic work machine includes: a rotation speed setting device that sets a target rotation speed for an engine; a rotation speed control device that controls an engine rotation speed so as to adjust the engine rotation speed to the target rotation speed; a first variable hydraulic pump used to drive a work hydraulic actuator, driven by the engine; a second variable hydraulic pump used to drive a cooling fan, driven by the engine; and a pump control device that controls an output flow rate of the first variable hydraulic pump and an output flow rate of the second variable hydraulic pump so as to ensure that a sum of an intake torque of the first variable hydraulic pump and an intake torque of the second variable hydraulic pump does not exceed an engine output torque determined in advance based upon the target rotation speed.

Abstract: A working fluid cooling control system has a controller 100 that receives inputs signals from a traveling motor speed pickup 101, a pressure sensor 102, a signal receiving line 103a of an option selecting switch 103 and a temperature sensor 104. The controller performs predetermined arithmetic processing and controls proportional solenoid valves 105 and 106. The pressures controlled by the solenoid valves are compared with positive control command pressures in shuttle valves 109 and 110. In this way, in the case of an operation pattern corresponding to a rise in temperature of the working fluid, minimum tilting angles of hydraulic pumps 11 and 12 are increased to increase an average flow rate of the working fluid passing through an oil cooler 40, thereby increasing an average heat discharge amount and reducing an equilibrium temperature of the working fluid.

Abstract: In a hydraulic control arrangement for an automated shift transmission, in particular a dual clutch transmission in a motor vehicle including a hydraulic control arrangement, the hydraulic control arrangement has a main pump and a controllable additional pump which jointly ensure that oil is supplied to the hydraulic control arrangement. The additional pump can feed into a control channel of a lubricating pressure slide and build up an adjustable lubricating fluid control pressure. The lubricating fluid pressure in the lubricating cooling system is adjusted in a simple and inexpensive manner by lubricating pressure slide changes modifying the lubricating control pressure in the lubricating cooling system.

Abstract: A hydraulically driven industrial machine having a variable displacement type hydraulic pump adapted to take in and pressurized working oil from an working oil tank, a hydraulic actuator to be driven by pressurized working oil delivered from the hydraulic pump through a control valve to perform a predetermined job, a variable return oil cooling means capable of cooling return oil from the hydraulic actuator at a varying cooling rate, an operational load detection means adapted to detect an operational load factor of the hydraulic actuator, and a control means adapted to vary the return oil cooling rate on the basis of an operational load factor detected by the operational load detection means.

Abstract: An oil cooling and filtering circuit connecting a reciprocating fluid power hydraulic cylinder to a reversible hydraulic pump or hydraulic directional valve. The circuit consists preferably of a three-way, three-position valve and a purge relief valve, which functions to divert a percentage of the low pressure oil coming out of the cylinder work port to an oil cooler. Instead of the fluid simply moving back and forth in the line and become overheated due to fluid friction and repeated pressurization, the working fluid in the line to the cylinder work port is circulated out of the fluid line and gradually replaced with cooled oil. The circuit itself does not perform cooling, but it provides a means to send trapped oil to an oil cooler. A secondary advantage is to provide filtration to the oil that is removed for cooling.

Abstract: A compressed-air energy storage system according to embodiments of the present invention comprises a reversible mechanism to compress and expand air, one or more compressed air storage tanks, a control system, one or more heat exchangers, and, in certain embodiments of the invention, a motor-generator. The reversible air compressor-expander uses mechanical power to compress air (when it is acting as a compressor) and converts the energy stored in compressed air to mechanical power (when it is acting as an expander). In certain embodiments, the compressor-expander comprises one or more stages, each stage consisting of pressure vessel (the “pressure cell”) partially filled with water or other liquid. In some embodiments, the pressure vessel communicates with one or more cylinder devices to exchange air and liquid with the cylinder chamber(s) thereof. Suitable valving allows air to enter and leave the pressure cell and cylinder device, if present, under electronic control.

Abstract: An electrohydraulic transmission controller (7), a transmission device with an electrohydraulic transmission controller and a vehicle drive train that features an electrohydraulic transmission controller are disclosed. The electrohydraulic transmission controller is constructed with a plurality of electrically actuatable pressure control valves (9 to 16), as well as with a plurality of valve arrangements (17 to 34) that can be acted on in each case by an hydraulic precontrol pressure depending upon the actuation of the pressure valves, by way of which valve arrangements switching elements (A to E) of a transmission device can be acted on in each case with a control pressure to produce a required operating state of the transmission device.

Abstract: The invention relates to a drive with an energy recovery and retarder function. The drive (1) comprises a hydrostatic piston engine (12) which is connected to an accumulator (16) for storing pressure energy and to a pressure limiting valve (19) for generating a braking action. Arranged downstream of the pressure limiting valve (19) is a cooler (45). The drive (1) also comprises a hydraulic motor (35) for driving a cooler fan (33), wherein the hydraulic motor (35) is acted on with a pressure medium which is delivered by the hydrostatic piston engine (12).

Abstract: A hydraulic circuit for heavy equipment is disclosed, which utilizes a hydraulic fluid supplied from a hydraulic pump for driving a cooling fan, as a pilot signal pressure, without installing a separate constant displacement pilot pump for supplying the pilot signal pressure to a control valve for controlling the hydraulic fluid to be supplied to a working device such as a boom.

Abstract: A portable electromagnetic power system used as a remote alternate power source includes a water tank having an oil reservoir mounted on top of the tank with four cylinders extending through the tank and the two outer cylinders denoted the pressure cylinders and the two inner cylinders serving as accumulators with electromagnets mounted at the ends of each pressure cylinder for reciprocating an internal floating piston and each inner cylinder having a permanent magnet mounted at one end for actuating a magnetized floating piston disposed therein and each magnetized floating piston dividing the inner cylinder into an air chamber portion and a fluid chamber portion with the oil reservoir and the cylinders all in fluid flow registration with each other and the inner cylinders connected to a working pressure line that connects to a device, such as a hydraulic motor, so that the outer cylinder develop working pressure concomitant with the flow of oil therein that is directed to the inner (accumulator) cylinders fo

Abstract: A top cover (17) is provided at an upper position of a supporting structure (12) of heat exchange device (11), and an upper opening (20C) is configured to be provided in a detachable type cover (20) for constituting this top cover (17) at a position corresponding to a clearance (16) between a radiator (13) and an intercooler (15) which overlap in the flowing direction (A) of cooling air. Accordingly, when a cooling fan (7B) is rotatively driven, the upper opening (20C) allows cool cooling air to flow into the supporting structure (12) and to be supplied to the radiator (13) through the clearance (16) between the radiator (13) and the intercooler (15). As a result, only the radiator (13) which overlaps with the intercooler (15) can be efficiently cooled by the cool cooling air from the upper opening (20C).

Abstract: A hydraulic control device includes an oil pan; an oil pump; a strainer; a pressure regulating valve; an oil cooler; a cooler bypass valve with an input port that is connected with a cooler supply oil passage through which the hydraulic oil to be supplied to the oil cooler flows, wherein the input port is communicatively connected with an output port when the hydraulic pressure of the hydraulic oil within the cooler supply oil passage is equal to or greater than a predetermined valve opening pressure; and a cooler bypass oil passage that connects the output port of the cooler bypass valve with an intake oil passage between the strainer and the intake port of the oil pump.

Abstract: A hydraulic control system for a transmission includes a motor, a sump for storing a hydraulic fluid, and a dual element pump connected to the motor. The dual element pump has at least one input port connected to the sump, a first outlet port, and a second outlet port. The dual element pump provides a first volume of hydraulic fluid to the first outlet port and provides a second volume of hydraulic fluid to the second outlet port. The first volume is greater than the second volume. The first outlet port is connected to a diversion valve. The second outlet port is connected to a high pressure hydraulic circuit. The diversion valve is operable to transmit the hydraulic fluid from the first outlet port to a low pressure hydraulic circuit and the high pressure hydraulic circuit.

Abstract: The invention relates to a construction machine comprising a transmission, at least one hydraulic drive and a hydraulic circuit for supplying the hydraulic drive with hydraulic fluid, wherein at least one lubrication line is branched off from the hydraulic circuit, by means of which the transmission can be supplied with hydraulic fluid as a lubricant. The invention is characterized in that a dosing device is provided on the lubrication line, with which the supply of lubricant can be changed depending on an operating condition of the transmission.

Abstract: A hydraulic fluid cooling system for a pair of integrated hydrostatic transmissions includes a common reservoir holding hydraulic fluid and having hydraulic lines connecting the common reservoir to each integrated hydrostatic transmission, a hydraulic fluid reservoir inside each integrated hydrostatic transmission, and a pump for pumping fluid from each transmission's hydraulic fluid reservoir to the other transmission. An auxiliary hydraulic circuit is between the pair of integrated hydrostatic transmissions. The system pumps hydraulic fluid from one of the integrated hydrostatic transmission to the auxiliary hydraulic circuit, and the return line from the auxiliary hydraulic circuit may be connected to the other integrated hydrostatic transmission.

Abstract: A hydraulic control system includes a source of pressurized hydraulic fluid for providing a pressurized hydraulic fluid, a main line circuit in fluid communication with the source of pressurized hydraulic fluid, a regulation valve in communication with the source of pressurized hydraulic fluid, the regulation valve moveable between a plurality of positions, and a lubrication valve in communication with the regulation valve, the lubrication valve moveable between a plurality of positions. A lubrication circuit and a cooling circuit are in communication with the lubrication valve.

Abstract: A hydraulic system for an agricultural vehicle is proposed. The hydraulic system comprises a main hydraulic circuit, which is fed with hydraulic fluid by a main hydraulic pump, a variable displacement charge pump which supplies charge pressure to the main hydraulic pump, and a lubricating hydraulic circuits. In order to keep efficiency losses on the vehicle to a minimum, particularly at high engine speeds, part of the hydraulic fluid delivered by the charge pump can be diverted to the lubricating hydraulic circuit.

Abstract: A machine includes a hydraulic fan system for circulating cooling air through an engine compartment. Periodically, the fan rotation direction is briefly reversed in order to dislodge any material debris that may have accumulated at the inlet to the engine compartment. When a fan reversal event is initiated, the fan motor will continue to rotate due to angular momentum even after the pump output flow has been switched from a first motor port to a second motor port. During this continued rotation as the fan decelerates to zero speed, vacuum pressure levels can arise at the first motor port, and a pressure spike can develop at the second motor port. In order to alleviate these conditions, a pressure transfer valve briefly opens to facilitate fluid flow directly from the second motor port to the first motor port as the fan motor decelerates towards zero speed before reversing direction, simultaneously alleviating vacuum and pressure spike conditions.