Abstract:
A normally closed, electrical solenoid actuated, pressure compensated, proportional, hydraulic flow control valve (4) includes a fluid flow control poppet valve (5), a pilot operator (6), a solenoid operator (7) and a pressure compensator (8). The poppet valve (5) includes a poppet (31) and a seat (32). The pilot operator (6) includes a pilot (36) and a pilot seat (37). The solenoid operator (7) includes a solenoid tube (42) and an armature (44). The pressure compensator (8) Includes a pressure balanced pressure compensator spool (58), a smaller diameter differential pressure compensator control piston (64), and springs (61) that balance the forces on the compensator control piston (64). The compensator control piston (64) moves the compensator spool (58) to maintain a substantially constant pressure differential across the poppet valve (5). The valve (4) may be used in a variety of hydraulic systems. A similar normally opened valve (104) is also disclosed.
Abstract:
A normally closed, electrical solenoid actuated, pressure compensated, proportional, hydraulic flow control valve (4) includes a fluid flow control poppet valve (5), a pilot operator (6), a solenoid operator (7) and a pressure compensator (8). The poppet valve (5) includes a poppet (31) and a seat (32). The pilot operator (6) includes a pilot (36) and a pilot seat (37). The solenoid operator (7) includes a solenoid tube (42) and an armature (44). The pressure compensator (8) Includes a pressure balanced pressure compensator spool (58), a smaller diameter differential pressure compensator control piston (64), and springs (61) that balance the forces on the compensator control piston (64). The compensator control piston (64) moves the compensator spool (58) to maintain a substantially constant pressure differential across the poppet valve (5). The valve (4) may be used in a variety of hydraulic systems. A similar normally opened valve (104) is also disclosed.
Abstract:
Es wird eine hydraulische Anordnung (10) zur Erhöhung einer Motorlast beschrieben. Die hydraulische Anordnung umfasst einen hydraulischen Verbraucher (28), eine lastdruckgesteuerte Hydraulikpumpe (24), einen Hydrauliktank (26) und einen mit dem hydraulischen Verbraucher (28) verbundenen hydraulischen Steuerkreis (30), mit welchem ein von der Hydraulikpumpe (24) geförderter Volumenstrom veränderbar ist, wobei der hydraulische Steuerkreis (30) ein Überdruckventil (42) und ein elektronisch ansteuerbares Steuerventil (36) umfasst. Um eine Priorisierung des hydraulischen Verbrauchers bei gleichzeitiger Erhöhung der Motorlast sicherzustellen wird vorgeschlagen, dass der hydraulische Steuerkreis (30) zwischen Überdruckventil (42) und Steuerventil (36) eine lastdruckgesteuerte Druckwaage (38) umfasst.
Abstract:
An apparatus for determining the weight of a payload (44) in a bucket (24) of a machine (20) where the bucket (24) is attached to a chassis (26) of the machine (20) by a linkage. The apparatus comprises an energy storage device (82) for storing potential energy of the bucket (24), payload (44), and linkage when the bucket (24) is moved from a first suspended position to a second suspended position. A mechanism (86) provides physical data corresponding to a physical change in the energy storage device (82) caused by storage of the potential energy and a processor (116) calculates the weight of the payload (44) using the physical data.
Abstract:
A system (10) and method for performing a floating function in an earthmoving implement (12) of an earthmoving machine (14) without physically connecting chambers within a hydraulic actuator (16) that is adapted to raise and lower the earthmoving implement (12). The system (10) includes a device (18) for delivering a pressurized fluid to and receiving pressurized fluid from the actuator (16), a valve (22) for compensating for differences in volume between chambers of the actuator (16), and an electronic control circuit that includes electronic sensors (36, 38) for sensing the pressures in the chambers of the actuator (16), and a controller (34) for receiving outputs of the sensors (36, 38). The controller (34) calculates an amount of the pressurized fluid that, when delivered to or received from the actuator (16), achieves a substantially constant pressures in the chambers of the actuator (16) and enables the earthmoving implement (12) to float regardless of motion of the actuator (16).
Abstract:
A hydraulic assembly and method for use with an vehicle engine exhaust flow control valve for controlling flow to at least one intake supply. The assembly has an actuator, such as a spring return piston cylinder (12), for positioning the control valve. An inlet passage (9), communicating with the cylinder, is arranged for supplying hydraulic fluid to a side of the actuator and a drain is arranged for draining the hydraulic fluid from the side of the actuator. An on-off type hydraulic valve (17), communicating with the drain, is operably coupled to the cylinder for controlling communication of the hydraulic fluid from the cylinder side to the drain. When the hydraulic assembly is in use, the pressure of hydraulic fluid acting on the actuator is adjustable by operation of the on-off type valve thereby to control movement of the actuator and, in turn, movement of the control valve.
Abstract:
A hydraulic system (22) for a work machine (10) is disclosed. The hydraulic system has a reservoir (34) configured to hold a supply of fluid and a source (18) configured to pressurize the fluid. The hydraulic system also has a fluid actuator (30), a first valve (27), and a second valve (32). The first valve is configured to selectively fluidly communicate the source with the fluid actuator to facilitate movement of the fluid actuator in a first direction. The second valve is configured to selectively fluidly communicate the fluid actuator with the reservoir to facilitate movement of the fluid actuator in the first direction. The hydraulic system further has a proportional pressure compensating valve (36) configured to control a pressure of a fluid directed between the fluid actuator and the reservoir.
Abstract:
The difference between the delivery pressure from a fixed displacement hydraulic pump (2) and the highest load pressure from among a plurality of actuators (3a - 3c) is maintained at a target pressure difference by an unloading valve (5). The set pressure for the unloading valve (5) is changed according to the engine rpm by introducing a pressure difference DELTA Pp across a choke (50) installed in the delivery path for a fixed pump (30) into a pressure receiving section (5d). This, in a hydraulic driving device having an LS system, makes it possible to secure fine operability due to the setting of engine rpm, flow control with good responsiveness, and excellent operability.