The present invention controls the pressure and flow rate of fluid, in order to obtain uniform performance, configure a closed loop magnetic circuit so as to include an electromagnet, a flapper, and a yoke material, and elastically deform the flapper itself by Maxwell attractive force generated between a magnetic pole of the electromagnet and the flapper to make the separation distance between the nozzle and the flapper variable. As opposed to a rigid flapper structure that swingably moves around a supporting point, like a conventional servo valve, the electromagnet, the magnetic pole, the nozzle, the flapper, and the like are arranged such that a change in magnetic gap directly leads to a change in air gap.

A single stage flapper type servovalve comprises a valve housing comprising a bore, a pair of opposed nozzles arranged in the bore and a flapper element arranged between the pair of nozzles. The valve housing further comprises a plurality of fluid ports for communicating a working fluid to and from the nozzles and in fluid communication with the housing bore. The valve housing and the nozzles are both made from a stainless steel material.

A valving system has an actuator member connected to move with an actuator piston and change the position of a valve member. There is a smaller face fluid chamber acting on a small area piston face, and a larger face fluid chamber acting on a larger face of the actuator piston. The torque motor has an armature and a flapper caused to move by current received at the armature. The flapper moves between two fluid ports to control the pressure in the larger face chamber. The flapper further has a positioning extension engaging a first feedback spring operable between it and a forward face of the actuator piston and providing a spring force in combination with a spring force from the positioning extension. A control is operable to provide current to the armature to control the fluid received in the larger face chamber. The controller is programmed to associate the current supplied to the armature to an actual position of the valve member. A method is also disclosed.

Methods and apparatus for quantifying pneumatic volume usage via valve controllers are disclosed. An example apparatus includes a valve controller operatively couplable to a pneumatic actuator, the pneumatic actuator being operatively coupled to a control valve. In response to an input signal indicating that a flow control member of the control valve is to be moved in a specified direction, the valve controller commands a current-to-pressure (I/P) converter of the valve controller to pulse a relay valve of the valve controller between a closed position and an open position. The pulsing of the relay valve causes the pneumatic actuator to move the flow control member in the specified direction. The valve controller calculates a pneumatic volume usage associated with the moving of the flow control member in the specified direction. The pneumatic volume usage is based on the pulsing of the relay valve.

A variable flow hydraulic device having a plurality of cylinders for varying a flow of hydraulic fluid between a reservoir and a load, the device comprising: a housing having the plurality of cylinders with a plurality of corresponding pistons; an input port of the housing fluidly connected to each cylinder of the plurality of cylinders, the input port facilitating introduction of the hydraulic fluid to said each cylinder; a first output port of the housing connected to said each cylinder, the first output port facilitating the ejection of the hydraulic fluid from said each cylinder, the first output port configured for fluidly coupling said each cylinder to the load; a respective flow control valve for said each cylinder, and a fluid pressure sensing device coupled between downstream of the first output port and said respective flow control valve.

A servo valve assembly includes a housing defining a cylindrical cavity having a central axis, and a spool disposed in the cavity and co-axially aligned with the central axis. A pair of transition portions define opposing conical cavity surfaces each connect a respective one of first and second cylindrical cavity portions with a third cylindrical cavity portion. The spool comprises a pair of blocking members projecting radially, and each of the blocking members defines a conical blocking surface opposing a respective one of the conical cavity surfaces to define a fluid flow passage therebetween. A cone angle of each conical blocking surface relative to the central is equal to a cone angle of the opposing conical cavity surface relative to the central axis. The spool is moveable along the central axis to vary a flow area of the flow passages between the conical blocking surfaces and the conical cavity surfaces.

An adjustable electro-pneumatic converter or transducer based on the nozzle/baffle plate principle is proposed. A defined roughness (Rz) of the baffle plate surface can prevent the occurrence of Bernoulli forces at output pressures close to the initial pressure, i.e. when the exhaust nozzle (140) is almost completely closed by the baffle plate (100). The system thus becomes more dynamically controllable under these conditions. Such a converter can be used to control any consumer system, e.g. air power amplifiers for electro-pneumatic positioners.

A variable flow hydraulic device having a plurality of cylinders for varying a flow of hydraulic fluid between a reservoir and a load, the device comprising: a housing having the plurality of cylinders with a plurality of corresponding pistons; an input port of the housing fluidly connected to each cylinder of the plurality of cylinders, the input port facilitating introduction of the hydraulic fluid to said each cylinder; a first output port of the housing connected to said each cylinder, the first output port facilitating the ejection of the hydraulic fluid from said each cylinder, the first output port configured for fluidly coupling said each cylinder to the load; a respective flow control valve for said each cylinder, and a fluid pressure sensing device coupled between downstream of the first output port and said respective flow control valve.

A pneumatic amplifier includes a valve body, a first comparison chamber, a third comparison chamber and a second comparison chamber. A first diaphragm and a second diaphragm are arranged in the first comparison chamber and fixed to the valve body. A mounting plate A is fixedly arranged between the first diaphragm and the second diaphragm. A seventh diaphragm, an eighth diaphragm, a ninth diaphragm and a tenth diaphragm are arranged in the second comparison chamber and fixedly arranged on the valve body. A mounting plate C is fixedly arranged among the seventh diaphragm, the eighth diaphragm, the ninth diaphragm and the tenth diaphragm. A third diaphragm, a fourth diaphragm, a fifth diaphragm and a sixth diaphragm are arranged in the third comparison chamber and fixed to the valve body. A mounting plate B is fixedly arranged among the third diaphragm, the fourth diaphragm, the fifth diaphragm and the sixth diaphragm.

A pneumatic amplifier includes a valve body, a first comparison chamber, a third comparison chamber and a second comparison chamber. A first diaphragm and a second diaphragm are arranged in the first comparison chamber and fixed to the valve body. A mounting plate A is fixedly arranged between the first diaphragm and the second diaphragm. A seventh diaphragm, an eighth diaphragm, a ninth diaphragm and a tenth diaphragm are arranged in the second comparison chamber and fixedly arranged on the valve body. A mounting plate C is fixedly arranged among the seventh diaphragm, the eighth diaphragm, the ninth diaphragm and the tenth diaphragm. A third diaphragm, a fourth diaphragm, a fifth diaphragm and a sixth diaphragm are arranged in the third comparison chamber and fixed to the valve body. A mounting plate B is fixedly arranged among the third diaphragm, the fourth diaphragm, the fifth diaphragm and the sixth diaphragm.