An connecting structure of an electromagnetic valve includes: a first connecting structure body that prohibits a relative movement between a hydraulic pressure circuit body and an electromagnetic valve in an axis line direction; a second connecting structure body that prohibits a relative movement therebetween in a plane orthogonal to the axis line direction; a third connecting structure body that prohibits a relative rotation about the axis therebetween; and a connection body that is prohibited from moving relatively to the hydraulic pressure circuit body, wherein the first connecting structure body includes a first target connection tool that is provided in an accommodation body and a first connection tool that locks the first target connection tool in the axis line direction at a wall portion constituting an accommodation space.

A hydraulic system includes a hydraulic pump. A first hydraulic shock is coupled to a first port of the hydraulic pump. A second hydraulic shock is coupled to a second port of the hydraulic pump. A first hydraulic cylinder is coupled to the first port of the hydraulic pump. A second hydraulic cylinder is coupled to the second port of the hydraulic pump. A first valve is coupled between the first hydraulic cylinder and second hydraulic cylinder. The first valve can be actuated by a computer system or can be a ball and spring check valve. A second valve is coupled between the first hydraulic cylinder and second hydraulic cylinder. A flow direction of the second valve is opposite a flow direction of the first valve. A first piston is disposed in the first hydraulic cylinder, and a second piston is disposed in the second hydraulic cylinder.

A cargo vehicle includes a hydraulic pump driven by an engine, a cargo handling apparatus operated by hydraulic oil from the hydraulic pump, a cargo operating unit for performing an instruction operation to operate the cargo handling apparatus, an electromagnetic proportional control valve disposed between the hydraulic pump and the cargo handling apparatus, a valve controller that controls the electromagnetic proportional control valve depending on an operation state of the cargo operating unit, and a revolution detector that detects a revolution of the engine, wherein the valve controller controls the electromagnetic proportional control valve such that an opening degree of the electromagnetic proportional control valve is limited for a certain time when the revolution of the engine detected by the revolution detector is lower than a predetermined value.

A cargo vehicle includes a hydraulic pump driven by an engine, a cargo handling apparatus operated by hydraulic oil from the hydraulic pump, a cargo operating unit for performing an instruction operation to operate the cargo handling apparatus, an electromagnetic proportional control valve disposed between the hydraulic pump and the cargo handling apparatus, a valve controller that controls the electromagnetic proportional control valve depending on an operation state of the cargo operating unit, and a revolution detector that detects a revolution of the engine, wherein the valve controller controls the electromagnetic proportional control valve such that an opening degree of the electromagnetic proportional control valve is limited for a certain time when the revolution of the engine detected by the revolution detector is lower than a predetermined value.

A control device, for a hydraulic consumer (22) and susceptible to vibrations, includes a valve (24) having a control spool (40) controllable by an actuating device (46). The valve (24) has a pressure supply port (P), to which a pressure compensator valve can be connected, which can be supplied with pressure fluid from a pressure supply device. The actuating device (46) has a motor (74). A load-pressure-dependent force on the control spool (40) can be generated by a control device (66). That force at the control spool (40) acts on an electronic motor controller (208) of the DC motor (74), which detects a change of the force and acts as a damping of the vibrations of the consumer (22) against this change of force.

A hydraulic system for an automatic transmission of a motor vehicle, including a high pressure circuit in which a pressure accumulator, at least one clutch and a gear selector are connected, and comprising a low pressure circuit for cooling the clutch, wherein the high pressure circuit and the low pressure circuit have at least one hydraulic pump that can be driven by an electric motor, and including a control unit that actuates the electric motor of the hydraulic pump when a pressure accumulator charging requirement is detected, wherein the high and low pressure circuits are connected via a bypass line to an integrated accumulator charging valve.

A hydraulic stage includes a hydraulic element located between and sealing a first and second chamber, wherein the first chamber comprises at least one aperture through which fluid is arranged to flow into or out of the first chamber; and at least one piezoelectric element which is positioned adjacent to the at least one aperture and is arranged to deform in response to an applied potential difference such that it blocks or obstructs the at least one aperture to a varying degree according to the level of deformation, so as to control fluid flow into or out of the first chamber. The level of deformation of the piezoelectric element thus reduces or increases an effective size of the inlet or outlet aperture to which it is adjacent, restricting or permitting an increase in fluid flow accordingly.

A hydraulic stage includes a hydraulic element located between and sealing a first and second chamber, wherein the first chamber comprises at least one aperture through which fluid is arranged to flow into or out of the first chamber; and at least one piezoelectric element which is positioned adjacent to the at least one aperture and is arranged to deform in response to an applied potential difference such that it blocks or obstructs the at least one aperture to a varying degree according to the level of deformation, so as to control fluid flow into or out of the first chamber. The level of deformation of the piezoelectric element thus reduces or increases an effective size of the inlet or outlet aperture to which it is adjacent, restricting or permitting an increase in fluid flow accordingly.

A header assembly for an agricultural harvesting machine comprises a first frame assembly, a second frame assembly that supports a cutter, and is movable relative to the first frame assembly, a float cylinder coupled between the first frame assembly and the second frame assembly, an accumulator, a controllable reservoir, and fluidic circuitry. The fluidic circuitry comprises a first conduit forming a first fluid path that provides a flow of pressurized fluid under pressure to the float cylinder, so the float cylinder exerts a float force on the second frame assembly, a valve mechanism that is actuatable to inhibit fluid flow along the first fluid path between the accumulator and the float cylinder, a second conduit forming a second fluid path fluidically coupled to the controllable reservoir, the controllable reservoir being controllable to add fluid to the float cylinder.

A tillage implement has a frame with a center section and first and second outer wing sections hingedly attached the center section such that the wing sections can be operably raised and lowered between a field-working position and a transport position. The sections each carry tillage tools for working the soil. Controlling a precharge in a secondary side of a hydraulic circuit enables the operator of the implement to adjust the downward pressure precharge provided by a plurality of hydraulic cylinders based on a desired stiffness of the implement. A pressure-reducing valve is configured such that flow from the hydraulic supply applies downward pressure precharge on the plurality of tillage tools. Once this desired precharge has been achieved, flow from the hydraulic supply is shut off and a check valve holds the pressure such that the plurality of hydraulic cylinders holds the tillage tools in position.