Welded pressure transducer

Claim 2

A force transducer comprising a housing including a rigid base, a piezoelectric element and an endpiece within said housing, said piezoelectric element being sandwiched between said endpiece and said base, and a preloading sleeve surrounding said piezoelectric element and formed at one end integral with said base, said preloading sleeve being spaced from the remainder of said housing and secured at its other end to said endpiece.

Claim 3

A transducer according to claim 1 wherein said preloading sleeve is welded to said endpiece.

Claim 4

A transducer according to claim 2 wherein said endpiece comprises a beryllium disc surrounded by a metal ring, said sleeve being welded to said ring.

Claim 5

A transducer according to claim 3 wherein said disc and ring are stepped to provide cooperating shoulders holding said ring and disc together.

Claim 6

A transducer according to claim 3 wherein said disc and ring are soldered together.

Claim 7

A transducer according to claim 2 wherein said endpiece comprises a ceramic disc surrounded by a metal ring, said sleeve being welded to said ring.

Claim 8

A force transducer comprising a housing including a rigid base, a coaxial connector mounted on said housing, at least one piezoelectric wafer and an endpiece mounted in said housing, said wafer being located between said endpiece and said base, a preloading sleeve surrounding said piezoelectric wafer and formed at one end integral with said base, said preloading sleeve beinG spaced from the remainder of said housing and welded at its other end to said endpiece, and an electrical lead in said housing coupling said piezoelectric wafer to said coaxial connector.

Claim 9

A force transducer comprising a housing including a rigid base, a coaxial connector mounted on said housing, at least one piezoelectric wafer and an endpiece mounted in said housing, said wafer being located between said endpiece and said base, a preloading sleeve surrounding said piezoelectric wafer and formed at one end integral with said base, said preloading sleeve beinG spaced from the remainder of said housing and welded at its other end to said endpiece, and an electrical lead in said housing coupling said piezoelectric wafer to said coaxial connector.

Claim 10

A force transducer according to claim 7 wherein said sleeve is connected to said endpiece by a plurality of circumferentially spaced spot welds.

Claim 11

A force transducer according to claim 7 wherein said sleeve and base are made of stainless steel, said endpiece comprising a central disc surrounded by a stainless steel ring.

Claim 12

A force transducer according to claim 7 wherein said piezoelectric wafer is made of X-cut quartz.

Claim 13

A force transducer according to claim 10 including a stack of X-cut quartz wafers within said sleeve, and a seismic mass within said sleeve and acting on at least one of said wafers.

Claim 14

A force transducer according to claim 7 including a mica disc between said endpiece and said piezoelectric wafer.

Claim 15

A pressure transducer comprising a housing including a rigid base, a coaxial connector mounted on said housing, a quartz crystal wafer and an endpiece mounted in said housing, said wafer being located between said endpiece and said base, a preloading sleeve surrounding said piezoelectric wafer and formed at one end integral with said base, said preloading sleeve being spaced from the remainder of said housing and secured at its other end to said endpiece, means in said housing coupling said quartz crystal wafer to said coaxial connector, and a metal diaphragm secured to the opposite end of said housing from said base for applying pressure forces to said end piece.

Claim 16

A pressure transducer comprising a housing including a rigid base, a coaxial connector mounted on said housing, a quartz crystal wafer and an endpiece mounted in said housing, said wafer being located between said endpiece and said base, a preloading sleeve surrounding said piezoelectric wafer and formed at one end integral with said base, said preloading sleeve being spaced from the remainder of said housing and secured at its other end to said endpiece, means in said housing coupling said quartz crystal wafer to said coaxial connector, and a metal diaphragm secured to the opposite end of said housing from said base for applying pressure forces to said end piece.

Claim 17

A pressure transducer according to claim 13 wherein said endpiece is welded to both said preloading sleeve and said diaphragm.

Claim 18

A pressure transducer according to claim 13 wherein said base, sleeve and diaphragm are all made of stainless steel, said endpiece comprising a central disc and a surrounding stainless steel ring, and a plurality of circumferentially spaced spot welds securing said ring to both said sleeve and said diaphragm.

Claim 19

A pressure transducer according to claim 15 wherein said ring and disc are both stepped to provide cooperating annular shoulders retaining said disc and ring together under the preloading pressure of said sleeve.

Claim 20

A pressure transducer according to claim 16 wherein said endpiece disc is made of beryllium.

Claim 21

A pressure transducer according to claim 13 including first and second groups of quartz crystal wafers between said endpiece and base, said first group having a greater number of wafers being located nearer said endpiece and separated from said second group by a seismic mass, the masses of said wafers and seismic mass being such that the outputs of said quartz crystal groups cancel for acceleration forces along the axis of said sleeve.