摘要:
There is disclosed a high pressure sensing header which is relatively insensitive to mounting torque. The header comprises an outer torque isolating shell which surround an inner “H” section header. The inner “H” section header has a thick diaphragm and is surrounded by the torque isolating shell which is secured to the “H” section header at a peripheral flange of the “H” section header. In this manner when the header is installed, the installation force is absorbed by the outer shell and there is no installation force or torque exhibited by the inner “H” section which will respond only to stress due to pressure. The torque isolating shell also contains a top surface which has a counterbore that accommodates a crush ring. When the unit is installed, the crush ring is crushed against an installation wall to enable the inner header to receive pressure without experiencing significant installation force.
摘要:
There is disclosed a high pressure sensing header which is relatively insensitive to mounting torque. The header generally includes an outer torque isolating shell which has a “C” shaped cross section with the cylindrical shell surrounding an inner “H” section header. The inner “H” section header has a thick diaphragm and is at least partially surrounded by the torque isolating shell. In this manner, when the header is installed, the installation force is absorbed by the outer shell and there is relatively no installation force or torque exhibited by the inner “H” section which will respond only to stress due to pressure.
摘要:
A joystick apparatus employs a hermetically sealed load cell having strain gauges placed on flexible beams formed on the load cell. All of the strain gauges are on the same surface of the load cell and therefore wiring is performed on a single side of the load cell. The strain gauges are enclosed in hermetically sealed cavity. The sensing diaphragm consists of a concentric thick inner and outer section joined by thinner diametrically opposed beam elements. The thin beam elements are compliant members which can deflect. Each beam includes strain gauges or sensor elements and the load cell is coupled to a joystick which when moved causes the beams to deflect to cause the sensor elements to produce an electrical output proportional to the force and direction of the joystick. The sensor can yield an output proportional to any angle over the 360° movement of the joystick to provide outputs proportional to the X and Y positions of said joystick. Thus, the joystick arrangement can resolve any angle or force into X and Y components for full directional control.
摘要:
A high pressure transducer has an H shaped cross-section with a center arm of the H having a top and bottom surface with the top surface of the H accommodating four strain gauges. Two strain gauges are located at the center of the top portion of the center arm of the H and are positive strain gauges, while two strain gauges are located near the periphery of the center arm of the gauge. The bottom surface of the center arm of the gauge has an active area of a smaller diameter than the circular diameter of the center arm portion of the transducer. The smaller active area is surrounded by a thicker stepped area which surrounds an active area on the pressure side of the H shaped member. The surrounding stepped area enables one to position the two negative strain gauges on the opposite surface of the center arm and near the periphery to thereby cause the negative gauges to respond to a negative stresses and therefore to enable one to provide a full Wheatstone bridge which includes the two positive strain gauges located at the center of the center arm of the H and the two negative peripheral gauges.
摘要:
A high temperature pressure transducer includes an extended tubular member having an opening from a front to a back surface. The tubular member is preferably fabricated from a metal. At the front end of the tubular member is a ceramic sensor face or tip which basically is a ceramic disk having a curved front surface and having an extending stem and which is inserted into the front opening of the tubular member. The column is of a given length and terminates in a back end. The back end has a predetermined portion which consists of two flat surfaces each on opposite sides. The back end containing the flat surfaces is thinner than the thickness of the column. On these flat surfaces are positioned suitable semiconductor piezoresistors. When a force is applied to the ceramic sensor face, it is transmitted axially through the tube or column where it is received by the sensors positioned on the flats. The sensors produce an output indicative of the force applied. The sensors may be arranged in a suitable bridge configuration.
摘要:
A hermetically sealed displacement sensor has strain gauges placed on thin flexible triangular shaped beams of a load beam cell. The strain gauges are enclosed in a hermetically sealed cavity which cavity is sealed by means of a cover plate placed over the load beam cell. The thin beams are connected together by a center hub and basically form two constant moment beams. There is a top isolation diaphragm member which is convoluted and to which a force is applied which applied force is transmitted to the thin flexible beams. The beams deflect and the sensors produce an output proportional to strain. The sensors on each beam are two in number wherein one sensor is placed in a longitudinal direction with respect to the beam while the other sensor is in a transverse position. The sensors may be wired to form a full Wheatstone bridge or half bridges may be employed. The electrical output from the strain gauge bridge is proportional to the deflection of the center of the sensor.
摘要:
A single pressure sensing capsule has a reference pressure ported to the rear side of a silicon sensing die. The front side of the silicon sensing die receives a main pressure at another port. The silicon sensing die contains a full Wheatstone bridge on one of the surfaces and within the active area designated as the diaphragm area. Thus, the difference of the main and reference pressure results in the sensor providing an output equivalent to the differential pressure, namely the main pressure minus the reference pressure which is the stress induced in a sensing diaphragm. In any event, the reference pressure or main pressure may be derived from a pump pressure which is being monitored. The pump pressure output is subjected to a pump ripple or a sinusoidally varying pressure. In order to compensate for pump ripple, one employs a coiled tube. The tube length is selected to suppress the pump ripple as applied to the sensor die. In this manner, the pump ripple cannot cause resonance which would result in pressure amplification and which pressure amplification would destroy the sensor.
摘要:
There is disclosed a high pressure sensing header which is relatively insensitive to mounting torque. Essentially the header consists of an outer torque isolating shell which has a “C” shaped cross section with the cylindrical shell surrounding an inner “H” section header. The inner “H” section header has a thick diaphragm and is surrounded by the torque isolating shell which is secured to the “H” section header at a peripheral flange of the “H” section header. In this manner when the header is installed, the installation force is absorbed by the outer shell and there is no installation force or torque exhibited by the inner “H” section which will respond only to stress due to pressure. The torque isolating shell also contains a top surface which has a counterbore which can accommodate a crush ring, and when the unit is installed, the crush ring is forced or crushed against an installation wall to enable the inner header to receive pressure without experiencing any significant installation force.
摘要:
There is disclosed a multiple axis load cell or controller in which axial and torsion measurements are decoupled while maximizing the outputs of both measurements. The active member of the load cell is a wheel with dual beams as the spokes. The wheel thus has four spokes or four beam members, each spoke is a pair of rectangular cross-section beams, orthogonal to each other. The beams have strain gages on the wide surfaces which measure the bending strain which is proportional to torsion or the axial input. There is an inner beam section and an outer beam section associated with each spoke and orthogonal to each other. The outer beams have the wide surface normal to the axis of the load cell. This beam section is more sensitive to the axial tension/compression input. The inner beam sections have their wide surface parallel to the axis of the load cell and are much less sensitive to bending but are sensitive to torsion. Therefore when a torsion or twisting motion is applied to the load cell, the inner beams with their wide surface parallel to the axis of the wheel are more sensitive and bend more. These beams experience bending as a result of the torsion input and have strain gages formed in a Wheatstone bridge arrangement to provide an output proportional to the torsion. The outer beams also have gages mounted thereon which are also wired in a Wheatstone bridge configuration and which Wheatstone bridge output of these gages are proportional to the axial force.
摘要:
A single pressure sensing capsule has a reference pressure ported to the rear side of a silicon sensing die. The front side of the silicon sensing die receives a main pressure at another port. The silicon sensing die contains a full Wheatstone bridge on one of the surfaces and within the active area designated as the diaphragm area. Thus, the difference of the main and reference pressure results in the sensor providing an output equivalent to the differential pressure, namely the main pressure minus the reference pressure which is the stress induced in a sensing diaphragm. In any event, the reference pressure or main pressure may be derived from a pump pressure which is being monitored. The pump pressure output is subjected to a pump ripple or a sinusoidally varying pressure. In order to compensate for pump ripple, one employs a coiled tube. The tube length is selected to suppress the pump ripple as applied to the sensor die. In this manner, the pump ripple cannot cause resonance which would result in pressure amplification and which pressure amplification would destroy the sensor.