Piezoelectric Blast Pressure Transducer (Patent No: 806818)

Inventor: Fenrick, Walter J.

Location: Medicine Hat

Comments: N/A

Description: The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A shock wave pressure-time gauge comprising a ferroelectric ceramic shear element, a force transmitting element fixedly bonded to one surface thereof, a mounting element fixedly bonded to the opposite surface thereof arranged to fixedly locate said ceramic element and a pressure responsive element adapted to move said transmitting element in response to a shock wave received by said pressure-responsive element so as to apply shear forces along the surface of said ceramic element and thereby generate a voltage difference between the faces of said ceramic element, means being provided for measuring said voltage difference.

2. A shock wave pressure-time gauge comprising a ferroelectric ceramic shear tube, a tubular mount coaxial with said ceramic element fixedly bonded to one surface of said ceramic tube and arranged to fixedly locate said ceramic tube, a force transmitting tube coaxial with said ceramic tube and fixedly bonded to the opposite surface of said ceramic tube and a pressure responsive element adapted to move said transmitting element in response to said shock wave pressure received by said pressure-responsive element so as to apply shear force along the surface of said ceramic element thereby to generate a voltage difference between said surface of said ceramic element, means being provided for measuring said voltage.

3. A gauge as claimed in claim 2 in which the force transmitting tube is bonded to the inside surface of said ceramic tube and the tubular mount to the outside surface of said. ceramic tube.

4. A gauge as claimed in claim 2 in which one end of the force transmitting tube extends beyond the end of the ceramic tube and said pressure-responsive element is a diaphram fixedly connected to said one end of said force transmitting tube.

5. A gauge as claimed in claim 2 in which the tubular mount is fixedly located in a gauge casing.

6. A gauge as claimed in claim 4 in which the tubular mount is fixedly located in a gauge casing, the diaphragm closing an open end of said casing.

7. A gauge as claimed in claim 5 or 6 in which the surfaces of the ceramic tube are electrically connected to the force transmitting tube and the tubular mount respectively, the voltage being taken from the device by means of a coupling for a coaxial cable.

8. A shock wave pressure-time gauge comprising a ferroelectric ceramic shear tube, a tubular mount coaxial with said ceramic tube bonded to the outer surface of said ceramic and fixedly mounted in a gauge case, a force transmitting tube coaxial with said ceramic tube and fixedly bonded to the inner surface of said ceramic tube, one end of said force transmitting tube extending beyond the ceramic tube and having a diaphragm on said one end which closes an open end in said case and is adapted to move said force transmitting element in response to a shock wave pressure so as to apply a shear force to said inner surface of said ceramic tube and thereby generate a voltage difference between said inner and outer surfaces of said ceramic tube, said inner surface of said tube being an electrical connection with said force transmitting tube and said outer surface being in electrical connection with said mount, means being provided for measuring the difference in voltage between said transmission tube and said mount.

9. A gauge as claimed in claim 1, 2 or 8 in which the ferroelectric ceramic shear element or tube is a lead zirconate-titanate element or tube.