Abstract: A direct-acting pressure sensor capable in the low-pressure range and including a pressure-sensitive assembly constituted by inner and outer concentrically-arranged curved springs anchored at one end in a socket to define a pressure region therebetween, within which is disposed an elongated, flexible bladder forming an internal pressure chamber communicating with a fluid input socket. The springs are joined at their free end to form a tip whose travel is indicative of the pressure of fluid applied to the sensor. The bladder initially assumes a curved form conforming to the curvature of the springs; but when subjected to internal pressure by an applied fluid, it seeks to straighten out to an extent determined by the level of pressure.

Abstract: A direct-acting pressure sensor operable in the low-pressure range and including a sub-assembly constituted by inner and outer concentrically-arranged curved springs anchored at one end in a socket to define a pressure region therebetween, within which is disposed a flexible bladder forming an internal pressure chamber communicating with the socket, the springs being joined at their free end to form a tip whose travel is indicative of the pressure of fluid applied to the sensor through said socket. The bladder which is preferably fabricated of reinforced elastomeric material is bonded to the springs to avoid slide friction therebetween and thereby minimize hysteresis.

Abstract: A direct-acting pressure sensor operable in the low-pressure range and including a sub-assembly constituted by inner and outer concentrically-arranged curved springs anchored at one end in a socket to define a pressure region therebetween, within which is disposed a flexible bladder forming an internal pressure chamber communicating with the socket, the springs being joined at their free end to form a tip whose travel is indicative of the pressure of fluid applied to the sensor through said socket, the range of the sensor being adjustable by means of a set screw adapted to engage the outer spring and to shift the theoretical pivot point of the sub-assembly.