Abstract:
A positioner operating mode identifying function is provided in a calculating unit. A pressure value of an amplified pneumatic pressure signal, from a single-mode pilot relay, is detected by a pressure sensor and sent to the calculating unit. The calculating unit, through the positioner operating mode identifying function, monitors a change in the amplified pneumatic pressure signal corresponding to a change in the control signal, and if the direction of change in the control output and the direction of change of the amplified pneumatic pressure signal are the identical direction, identifies the operating mode of the positioner as the positive operating mode. The operating mode of the positioner is identified as the negative operating mode if the direction of change in the control output and the direction of change of the amplified pneumatic pressure signal are the opposite directions. The identification results displayed on a screen of a display unit.
Abstract:
A low pressure pneumatic pressure regulator having particular application to the control circuits of system powered air distribution systems. A diaphragm separates a control chamber located above the diaphragm from an underlying output. The chambers communicate through a fixed orifice. A vent line extending from the control chamber includes an adjustable orifice which may be thermostatically controlled. An output line extending from the output chamber leads to the load controlled by the regulator. Power to operate the regulator can be supplied from the load or from a separate pressure source which connects with the output chamber through a supply port. An exhaust port which bleeds pressure from the output chamber when open is closed by the diaphragm unless the pressure differential between the chambers overcomes the diaphragm weight and possibly the added force applied by an optional spring. The pressure regulator can be used to control a number of terminal units from a common thermostat or as a pressure source for a number of terminal units each controlled by its own individual thermostat.
Abstract:
A circuit for pneumatic controllers, a proportional-action range of which is adjustable, with the circuit including at least one differential amplifier having input pressure chambers being exposed to pressures derived between two throttle resistors respectively inserted in the measured value X input line and the desired value W-input line. All of the resistors are constant and a connecting line is interposed between connecting sections of the resistors, with the connecting line being provided with an adjustable throttle resistor.
Abstract:
A pneumatic controller providing an outgoing signal proportional to the magnitude and time integral of the incoming signal comprises a first sealed-beam balance with a rigid beam attached onto a diaphragm defining four chambers, a second sealed-beam balance with two chambers performing the flow relay function, and a pressure balance with two chambers for copying the integral pressure. In the case of a pneumatic controller providing an outgoing signal proportional to the magnitude, time integral and time derivative of the incoming signal, the first sealed-beam balance is preceded by a time derivative stage comprised of a sealed-beam balance with four chambers similar in construction to the first sealed-beam balance.
Abstract:
A modulating valve is urged from its extreme closed position to its extreme open position by one end of a pivoted lever, and the modulating pressure is applied to a piston which acts on the other end of the pivoted lever to lock the modulating valve in its extreme open position until an external force is applied to the lever to move the modulating valve to its extreme closed position.
Abstract:
A housing means carrying a plurality of diaphragm members disposed in stacked relation and cooperating with the housing means to define a plurality of chambers disposed in stacked relation and separated from each other by the diaphragm members. Each diaphragm member has a central post means and a plurality of integral diaphragm portions axially spaced on the post means and extending radially outwardly therefrom in substantially parallel spaced relation to each other. Interconnecting means interconnect the post means of the diaphragm members together whereby the diaphragm members are adapted to move in unison in the housing means.
Abstract:
An electrically controlled hydraulic valve device of the selflapping type including a self-lapping supply valve for supplying hydraulic operating pressure to vehicle brake apparatus at a degree controlled by a pilot valve, which, in turn, is mechanically operated by a solenoid for causing the supply valve to supply at maximum operating pressure when the solenoid is completely deenergized, and to effect zero operating pressure and complete release thereof when the solenoid is fully energized, the degree of said operating pressure between said zero and maximum pressures being infinitely variable inversely to the degree of energization of the solenoid.
Abstract:
A dynamic pressure controller for generating a pressure at a desired value with high accuracy and stability. A manometer supplying an error signal varying as a function of the difference between a reference pressure and the pressure in the output line. A pair of control valves coupled to the output line, with one valve having a low-pressure source as an input and the other having a high-pressure source as the input, a pressure regulator connected across each of the control valves to maintain substantially constant pressure drop thereacross, and amplifiers for driving both valves as a function of the error signal, with the valves operating in the partially open condition for the zero pressure difference condition, and with the valves having floating poppets actuated magnetically against nonmagnetic seats.
Abstract:
A pneumatic controller provided with a flapper-nozzle assembly and an actuator-arm assembly. The flapper-nozzle assembly includes a flapper having a blade section and a flat tab section such that deflection of the tab section causes the blade section to move relative to the orifice of a nozzle to more or less throttle the rate of fluid flow through the nozzle. The flappernozzle assembly is rotatable, whereby the angular orientation of the plane of the tab section may be varied with respect to a Yaxis passing through the nozzle. The actuating-arm assembly includes a swizzle stick mounted on a transverse staff extending along an X-axis perpendicular to the Y-axis, the swizzle stick having a ball at one end thereof engaging the tab section of the flapper. The stick is caused to swivel on the staff about the Xaxis as a function of an applied error signal motion, and is also caused to shift along the X-axis as a function of a feedback signal motion whereby the position of the ball is the resultant of the error and feedback signals, and the degree to which it deflects the tab section of the flapper depends on the angle of this section with respect to the Y-axis.