An electroacoustical transducer is disclosed as incorporating a metallic sing having an aperture located in the wall thereof. A plurality of shutters are rotatably mounted on said housing for effectively and timely opening and closing predetermined portions of said aperture. A plastic support member is disposed within said housing, and a slot is located therein in alignment with said aperture. A wooden frame is disposed in said slot in such manner as to effect a semi-resilient lining therefor, a...

A magnetostrictive pressure transducer is disclosed wherein pressure in the range of 0 to 1000 psi can be accurately measured. The pressure transducer apparatus includes a diaphragm causing the pressure to be applied unidirectionally on sensor material having the property of undergoing changes in magnetic induction when a pressure is applied thereto, the change in magnetic induction being related to the applied pressure. The change in magnetic induction is measured and thus provides a measuremen...

A static pressure compensated transducer wherein two leaf spring cantilever beams are located in the same chamber. Each beam has a strain gage glass bonded to each side thereof. One beam is deflected by a differential pressure unit (DPU) while the other is left without any deflection. The strain gages are then connected in a Wheatstone bridge and the bridge output is directly proportional to the one beam deflection and independent of the fluid pressure in the chamber. The bridge output is thus m...

A magnetostrictive pressure transducer is disclosed wherein pressure in the range of zero to 1000 psi can be accurately measured. The pressure transducer apparatus includes a diaphragm causing the pressure to be applied unidirectionally on sensor material having the property of undergoing changes in magnetic induction when a pressure is applied thereto, the change in magnetic induction being related to the applied pressure. The change in magnetic induction is measured and thus provides a measure...

1. A transducer comprising in combination, a plurality of piezoelectric discs arranged along a common axis of revolun in the order of increasing diameters in the aft to forward direction, resilient means interposed between each of said piezoelectric discs for the support thereof with a predetermined relative degree of freedom of movement, means effectively connected to the end ones of said piezoelectric discs for the urging thereof toward each other by compressing the resilient support means int...

In a transducer, e.g. a pressure transducer, the sensing element comprises a torsional oscillator provided with magnetic means for feedback of signals to maintain oscillation. Typically the sensing element is formed by selective etching from a body of single crystal silicon.

Transducing of a fluidic signal to an electric signal is accomplished in two steps by causing the fluidic signal to operate a whistle and then directing the resultant acoustical energy against a piezoelectric crystal that in sympathetically vibrating produces a low voltage output signal which can be used to control a suitable amplifying and rectifying electric circuit.

A transducer for extra-uterine monitoring of fetal heart rate and labor activity comprises a casing the lower portion of which carries ultrasound crystals. Additional crystals are carried by a movable base plate which is connected with tension-measuring means.

A passive electrically operable monitoring means has an inherent resistance and a characteristic capacitance and inductance only, so that the monitoring means has a predetermined natural frequency of oscillation. Variations in a physical parameter being monitored by the monitoring means will cause the characteristic capacitance and/or inductance to vary thereby varying the natural frequency of oscillation of the monitoring means. A transducer includes an excitation means for exciting the monitor...

A dual differential pressure/static pressure unit including a housing and three approximately parallel diaphragms sealed therewith forming low and high pressure compartments. Incompressible fluid then fills the respective spaces between the center diaphragm and that on each side thereof. Differential pressure/static pressure sensors are then provided. The housing is provided with passageways to conduct each of said fluids to the respective high and low pressure sides of said sensors.