Sinusoidal pressure calibrator

Claim 2

A dynamic pressure calibrator comprising a housing for attachment to a shaker table, said housing including a cavity adapted to receive a pressure fluid, means on said housing for mounting a test pressure transducer with its working face in fluid communication with said cavity, a seismic mass mounted in said housing, and a piston connected to said mass and having one end in fluid communication with said cavity for applying a variable pressure force through the fluid in said cavity to the working face of said test transducer.

Claim 3

A pressure calibrator according to claim 1 including a piezoelectric test transducer on said mounting means with its working face in fluid communication with said cavity.

Claim 4

A pressure calibrator according to claim 1 including an accelerometer connected to said seismic mass for indicating the acceleration of said mass.

Claim 5

A pressure calibrator according to claim 3 wherein said accelerometer is a piezoelectric accelerometer.

Claim 6

A pressure calibrator according to claim 3 including means in said housing for applying a preloading force to said mass and piston.

Claim 7

A pressure calibrator according to claim 5 wherein said preloading means comprises a spring urging said mass and piston toward said cavity.

Claim 8

A dynamic pressure calibrator comprising a housing for attachment to a shaker table, said housing including a cavity adapted to receive a pressure fluid, first means on said housing for mounting a test pressure transducer with its working face in fluid communication with said cavity, second means on said housing for mounting a standard pressure transducer with its working face in fluid communication with said cavity, a seismic mass of known weight mounted in said housing, a piston connected to said mass and having one end in fluid communication with said cavity for simultaneously applying a variable pressure force through the fluid in said cavity to the working face of each of said transducers, and means in said housing for coupling an accelerometer to said seismic mass for sensing its acceleration.

Claim 9

A dynamic pressure calibrator comprising a housing for attachment to a shaker table, said housing including a cavity adapted to receive a pressure fluid, first means on said housing for mounting a test pressure transducer with its working face in fluid communication with said cavity, second means on said housing for mounting a standard pressure transducer with its working face in fluid communication with said cavity, a seismic mass of known weight mounted in said housing, a piston connected to said mass and having one end in fluid communication with said cavity for simultaneously applying a variable pressure force through the fluid in said cavity to the working face of each of said transducers, and means in said housing for coupling an accelerometer to said seismic mass for sensing its acceleration.

Claim 10

A pressure calibrator according to claim 7 including a piezoelectric accelerometer coupled to said seismic mass.

Claim 11

A pressure calibrator according to claim 8 wherein said accelerometer is received within said seismic mass.

Claim 12

A pressUre calibrator according to claim 8 wherein said accelerometer is mounted on a rod connected to said seismic mass and extending through an aperture in said housing.

Claim 13

A dynamic pressure calibrator comprising a two-piece housing having first and second sections connected together, means on one of said sections for connecting said housing to a shaker table, one of said sections including a cavity filled with hydraulic oil, a piezoelectric test pressure transducer mounted on said one section with its working face in contact with said oil, a piezoelectric standard pressure transducer mounted on said one section with its working face in contact with said oil, a seismic mass movably mounted in the other of said sections, a piston connected to said seismic mass and extending into said one section with its end contacting said oil for simultaneously applying a variable pressure force through said oil to the working face of each of said transducers, resilient preloading means in said other section urging said mass and piston toward said oil, and a piezoelectric transducer connected to said seismic mass for sensing its acceleration.

Claim 14

A dynamic pressure calibrator comprising a two-piece housing having first and second sections connected together, means on one of said sections for connecting said housing to a shaker table, one of said sections including a cavity filled with hydraulic oil, a piezoelectric test pressure transducer mounted on said one section with its working face in contact with said oil, a piezoelectric standard pressure transducer mounted on said one section with its working face in contact with said oil, a seismic mass movably mounted in the other of said sections, a piston connected to said seismic mass and extending into said one section with its end contacting said oil for simultaneously applying a variable pressure force through said oil to the working face of each of said transducers, resilient preloading means in said other section urging said mass and piston toward said oil, and a piezoelectric transducer connected to said seismic mass for sensing its acceleration.

Claim 15

A pressure calibrator according to claim 11 wherein said means for connecting said housing to a shaker table is on the housing section containing said oil.

Claim 16

A pressure calibrator according to claim 11 wherein said means for connecting said housing to a shaker table is on the housing section containing said seismic mass.

Claim 17

A pressure calibrator according to claim 11 including an adjustable preload plug threaded into said other section, said resilient preloading means comprising a helical spring compressed between said plug and said seismic mass.

Claim 18

A pressure calibrator according to claim 11 including a pressure adjustment screw threaded into said one section, said screw having its inner end in contact with said oil.

Claim 19

A pressure calibrator according to claim 11 including a selector switch to the output of both of said transducers and to the output of said accelerometer, and display means connected to said switch for selectively displaying one of said outputs.

Claim 20

A pressure calibrator according to claim 16 wherein said switch is coupled to said transducers and accelerometer through respective coupler amplifiers.