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"That the automobile has practically reached the limit of its development is suggested by the fact that during the past year no improvements of a radical nature have been introduced."
Scientific American ; Jan. 2 edition, 1909
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| Number | Title | Issue Date |
| 7225704 | Transmission for a working vehicle In a transmission for a working vehicle, a working unit includes a hydraulic power unit and a valve unit enclosed in a first bulging portion of a transmission case closer to an upper side or on a top surface thereof and connected with each other along a vehicle leng... | 06/05/2007 |
| 7171887 | Regulating device for hydrostatic piston machines The invention relates to a regulating device for hydrostatic piston machines consisting of an actuating piston (2) which can be removed between two end positions which can be impinged upon by actuating pressure exerted thereon in an opposite direction. An act... | 02/06/2007 |
| 7127887 | Oil pressure circuit for working machines A joining directional control valve 13 is disposed to supply, to an arm cylinder 4, not only a hydraulic fluid delivered from a first hydraulic pump 1, but also a hydraulic fluid delivered from a second hydraulic pump 2 when an arm direct... | 10/31/2006 |
| 6996979 | Hydraulic circuit for a hydraulic excavator A hydraulic circuit for a hydraulic excavator having a motor drive which acts on at least two closed drive circuits which are connected in parallel, each have a hydraulic pump and a hydraulic motor and which operate on a common output drive, connecting lines being p... | 02/14/2006 |
| 6904993 | Hydrostatic drive and method for operating such a hydrostatic drive A hydrostatic drive (1) with a hydraulic pump (3) and a plurality of hydraulic motors (6-9) that are hydraulically linked with the hydraulic pump (3). One speed sensor (20; 21; 22; 23) each allocated to a respective hydraulic motor... | 06/14/2005 |
| 6651428 | Hydraulic drive device Differential pressures across flow control valves 6a, 6b and 6c are controlled by pressure compensating valves 7a, 7b and 7c to be held at the same value, i.e., a differential pressure ƊPLS, and the differential pressure ƊPLS is maintained at a target d... | 11/25/2003 |
| 6422009 | Pump capacity control device and valve device A fixed throttle 12 is provided in a delivery line 11a of a fixed pump 11 driven by an engine 9 for rotation together with a hydraulic pump 1, and a differential pressure detecting valve 31 is provided in association with the fixed throttle 12 to detect a... | 07/23/2002 |
| 6276134 | Apparatus for controlling a plurality of hydraulic motors and a clutch An apparatus, for controlling a plurality of hydraulic motors and a clutch for driving a drive shaft, can prevent a speed change shock and a load slip of a hydraulic motor as well as making a structure simple. The apparatus includes: a first volume variab... | 08/21/2001 |
| 6226987 | Travel drive apparatus for hydraulic drive work vehicles and control therefor A travel drive apparatus for a hydraulic drive work vehicle of simple configuration, capable of preventing occurrence of cavitation which is predicted when a work vehicle is decelerated, descends a slope, or is changed from forward travel to reverse trave... | 05/08/2001 |
| 6192681 | Hydraulic drive apparatus A differential pressure ƊPLS between a delivery pressure of a hydraulic pump 2 and a maximum load pressure among a plurality of actuators 3a-3c is maintained at a target differential pressure ƊPLSref by pump displacement control means 5. The target ... | 02/27/2001 |
| 6105367 | Hydraulic drive system A hydraulic drive system wherein differential pressures across flow control valves are controlled by pressure compensating valves to become the same value, i.e., a differential pressure ƊPLS, and the differential pressure ƊPLS is maintained at a target ... | 08/22/2000 |
| 5746056 | Overspeed control for a hydrostatic transmission An overspeed control for a hydrostatic transmission of a mobile machine includes a speed control valve arrangement connected to a fixed displacement pump through a supply line and to a pressure responsive displacement controller of a variable displacement... | 05/05/1998 |
| 5638678 | Hydraulic drive system A hydraulic drive system includes a first driven hydrostatic machine adjustable in volume and operating as a pump supplying fluid to a supply line for maintaining an impressed pressure therein, a second hydrostatic machine which is adjustable in volume an... | 06/17/1997 |
| 5145324 | RAM air turbine driving a variable displacement hydraulic pump An improved RAM air turbine (30) for the generation of emergency power on an airplane is disclosed. The RAM air turbine has an operational range in which reduced power is produced by a power controller (40) at speeds at which stalling of the RAM air turbi... | 09/08/1992 |
| 5121603 | Device for pressure-regulated variable displacement motors with RPM-dependent set pressure compensation A hydrostatic system includes a variable displacement hydraulic motor whose absorption volume is adjusted by a pressure regulator, depending on the rpms generated by the power source driving the system. The apparatus enables the variable displacement moto... | 06/16/1992 |
| 5101628 | Energy regenerative circuit in a hydraulic apparatus An energy regenerative circuit in a hydraulic apparatus wherein when a direction control valve is at the actuator unloaded-side chamber acting position, the discharge fluid line of a variable displacement pump is connected to a fluid tank via the directio... | 04/07/1992 |
| 4819429 | Hydraulical drive system A hydraulic drive system to actuate the piston of a cylinder unit comprises a first hydrostatic machine having variable displacement, a second hydrostatic machine mechanically coupled to said first machine and operating as a signal generator either in a p... | 04/11/1989 |
| 4810171 | Regulator for an adjustable hydrostatic machine A regulator for an adjustable hydrostatic machine (1) having a hydraulic servo controller (4) for continuous variation of the displacement volume, with a valve device (16, 18) for controlling or regulating the servo controller (4) in dependence on the dis... | 03/07/1989 |
| 4745746 | Power control for a hydrostatic transmission The present invention is directed to a power control for an automatic transmission which consists of two valves, the first of which is a characteristic valve providing a pressure differential linearly proportional to an input speed signal provided by a pr... | 05/24/1988 |
| 4711616 | Control apparatus for a variable displacement pump A control apparatus for a variable displacement pump includes a variable displacement pump having an inlet port and a discharge port driven by an external engine. A piston assembly is provided for varying the amount of displacement of the pump. The contro... | 12/08/1987 |
| 4680931 | Constant speed control for positive displacement variable stroke hydraulic motor In a positive displacement variable stroke motor, a constant speed variable power drive governor is disclosed which varies stroke instead of driving pressure and hence conserves power through reducing throttling losses. Typically, the control is used on a... | 07/21/1987 |
| 4649705 | Composite hydraulic system A composite hydraulic system for a work vehicle which has two separate hydraulic circuits. Included in the composite system are three pumps, two of which supply the two circuits on the vehicle. A third pump transfers hydraulic fluid between the two hydrau... | 03/17/1987 |
| 4621495 | Synchronized mechanical-hydrostatic gearbox A synchronized mechanical-hydrostatic gearbox with infinitely variable drive ratio including a hydrostatic gear and a following mechanical gear coupled thereto. The hydrostatic gear includes a hydraulic transmission motor with variable displacement which ... | 11/11/1986 |
| 4620417 | Control device for a hydrostatic gear driven by a drive engine A control device for a hydrostatic gear driven by a drive engine, preferably an internal-combustion engine, is described, having an auxiliary pump, which is driven synchronously with the drive engine speed, for the generation of a control pressure which m... | 11/04/1986 |
| 4613286 | Constant torque control system for a variable displacement pump or pumps A control system for a variable displacement pump or pumps driven by a vehicular engine for supplying pressurized fluid to implement actuators via implement control valves. Included is a servomechanism comprising a servoactuator section coupled to each va... | 09/23/1986 |
| 4596118 | Hydrostatic self-regulating drive system A hydrostatic drive system has an internal combustion engine, a main pump driven by the engine and having a control element displaceable to vary the pump displacement, a control pump driven by the engine, an output motor having a control element displacea... | 06/24/1986 |
| 4566274 | Control device for a hydrostatic drive Disclosed is a control arrangement for a hydrostatic drive of the type having a power-driven adjustable pump, a pressure responsive setting cylinder coupled to the pump, a hydraulic motor connected via pressure conduits to the pump and a measuring motor c... | 01/28/1986 |
| 4561250 | Hydraulic drive system having a plurality of prime movers A hydraulic drive system including at least one hydraulic actuator, two variable displacement hydraulic pumps each connected to the hydraulic actuator to form a closed circuit therewith and connected in parallel with each other, two prime movers each driv... | 12/31/1985 |
| 4559778 | Control device for a hydrostatic transmission An apparatus for use in controlling a variable displacement pump in a hydrostatic transmission comprises servo-positioning means for varying the displacement of the variable displacement pump, signal producing means for producing a first signal dependent ... | 12/24/1985 |
| 4545201 | Control arrangements for regulating the speed of a hydrostatic energy consumer Control arrangement for regulating the speed of movement of a hydrostatic energy consumer is provided in which the ratio between pressure supplied and power on the output side is constant, in particular, a piston capable of sliding in a cylinder connected... | 10/08/1985 |
| 4531367 | Control and regulating means for an adjustable hydrostatic unit A control and regulating arrangement for an adjustable hydrostatic unit is provided in which the regulating device has an auxiliary control constant pump in the feed line of which there is a restrictor, in which case the pressure retained in front of the ... | 07/30/1985 |
| 4527393 | Control device for a hydrostatic transmission A control device for a hydrostatic transmission including apparatus for sensing a speed of a prime mover which powers a variable displacement pump of the hydrostatic transmission and for regulating the displacement of the variable displacement pump in acc... | 07/09/1985 |
| 4498847 | Control system for variable displacement hydraulic pumps A control system for variable displacement hydraulic pumps for use in a hydraulically operated construction vehicle having a fixed displacement hydraulic pump, a plurality of reducing valves operatively interlocked with work implement control valve units ... | 02/12/1985 |
| 4496289 | Device for controlling and/or measuring operational parameters of an axial piston machine Disclosed is a device for controlling or measuring operational parameters of an axial piston machine. The tilting plate which engages and adjusts the stroke of the piston is provided with two opposite pivot pins supported in fixed bearings. At least one p... | 01/29/1985 |
| 4495766 | Controls for hydrostatic systems In a control for a hydrostatic drive system with a primary energy source and with an adjustable pump and at least one adjustable consumer of hydrostatic energy and with a pump adjusting piston connected with the adjusting element of the pump and capable o... | 01/29/1985 |
| 4480963 | Pump swashplate control assist A hydrostatic drive system includes a hydraulic motor driven by a variable displacement axial piston pump with alternative intake and output ports. A charge pump generates a charge pressure which is communicated only to the pump intake port via a charge v... | 11/06/1984 |
| 4480438 | Power transmission A hydraulic system comprising a reversible variable displacement pump, a hydraulic servo motor for controlling the direction and amount of displacement of the pump, a fluid motor connected in parallel to the pump and adapted to be driven by the pump, a pi... | 11/06/1984 |
| 4474104 | Control system for variable displacement pumps and motors A hydraulic motor control system comprises a speed control loop and a pressure control loop which provide closed loop control of a variable displacement chamber space and the mechanical advantage coupling thereof to the motor output shaft. The speed contr... | 10/02/1984 |
| 4426195 | Adjustable axial flow piston machines In an adjustable axial flow piston pump having a swivellable component such as a swash plate, pressure chambers for swivelling the swivellable component, a lever connected with the swivellable component and supported in the housing of the pump, a final co... | 01/17/1984 |
| 4405287 | Regulating devices for a plurality of pumps driven by a common source A regulating device is provided for an aggregate of several pumps driven by a primary source at least one of which is adjustable and with a constant volume auxiliary control pressure pump driven by the same primary source in the delivery line of which a r... | 09/20/1983 |
