Patent US3749948A successfully refreshed from Google Patents.
US3749948A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure transducer
Assignee: Seismic Logs Inc
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Filing: 1971-06-21
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Granted: 1973-07-31
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Expires: 1991-06-21
Abstract
Abstract A pressure transducer comprises a cylindrical housing, a damping compound filling the housing and two sets of opposed dished piezoelectric crystals mounted at axially spaced points in the housing and surrounded by the compound. The adjacent crystals of the sets are rigidly interconnected and the crystals are electrically connected such that outputs caused by changes in pressure are added and outputs caused by accelerations are cancelled. Pressure waves are admitted to the housing by way of apertures formed in the ends of the housing and diaphragms extending over the apertures and contacting the damping compound.
Inventors
- 👤 H Morris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:21
CPC Classifications
G; G01; G01L; G01L19/00; G01L19/02; G01L13/00; G01L13/02; G01L13/025; G01L19/0007; G01L19/0046; G01L9/00; G01L9/0041; G01L9/008
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
181 words
A pressure transducer including: a. a housing comprising a cylindrical case and a pair of end caps mounted on the ends of the case and each having an aperture formed through it, b. a damping compound filling the housing, c. a pair of diaphragms each extending over the aperture in one of the end caps and contacting the compound in the housing, d. two sets of piezoelectric crystals mounted at axially spaced points in the housing and each comprising: i. inner and outer piezoelectric crystals, ii. means separating the centers of the crystals, and iii. means maintaining the peripheries of crystals in contact, e. means rigidly interconnecting the two inner crystals; f. means forming electrical connections between the two outer crystals and the two inner crystals, respectively; g. a first plurality of resilient nubs secured to the peripheries of the crystals comprising each set for locating the sets radially relative to the housing; and h. a second plurality of resilient nubs secured to the housing on opposite sides of the outer crystals for locating the sets axially relative to the housing.
Claim 2
Dependent Claim
181 words
A pressure transducer including: a. a housing comprising a cylindrical case and a pair of end caps mounted on the ends of the case and each having an aperture formed through it, b. a damping compound filling the housing, c. a pair of diaphragms each extending over the aperture in one of the end caps and contacting the compound in the housing, d. two sets of piezoelectric crystals mounted at axially spaced points in the housing and each comprising: i. inner and outer piezoelectric crystals, ii. means separating the centers of the crystals, and iii. means maintaining the peripheries of crystals in contact, e. means rigidly interconnecting the two inner crystals; f. means forming electrical connections between the two outer crystals and the two inner crystals, respectively; g. a first plurality of resilient nubs secured to the peripheries of the crystals comprising each set for locating the sets radially relative to the housing; and h. a second plurality of resilient nubs secured to the housing on opposite sides of the outer crystals for locating the sets axially relative to the housing.
Claim 3
Dependent Claim
75 words
The pressure transducer according to claim 1 wherein the case and the end caps of the housing are formed from an insulating material and further including: an electrically conductive cylinder positioned within the case; a pair of electrically conductive washers each securing one of the diaphragms to one of the end caps; and means electrically interconnecting the cylinder and the washer whereby an electrostatic shield is formed around substantially the entire interior of the housing.
Claim 4
Dependent Claim
23 words
The pressure transducer according to claim 2 further including means securing the conductive cylinder against movement relative to the case of the housing.
Claim 5
Dependent Claim
54 words
The pressure transducer according to claim 3 wherein the means separating the centers Of the crystals of each crystal set comprises a metal disk positioned between the crystals and wherein the means maintaining the peripheries of the crystals of each set in contact comprises a ring of nonconductive cement extending around each crystal set.
Claim 6
Dependent Claim
40 words
The pressure transducer according to claim 4 further including amplifier means positioned within the housing, means connecting the amplifier means to the electrical connections between the crystals, and electrically conductive means extending from the amplifier means out of the housing.
Claim 7
Dependent Claim
136 words
A pressure transducer including: a. two sets of opposed dished piezoelectric crystals each comprising an inner crystal and an outer crystal, b. a housing enclosing the crystal sets and having opposed openings formed therein, c. means for detachably locating the crystal sets in the housing while permitting relative movement between the peripheries of the crystal sets and the interior of the housing, said locating means comprising resilient means fixed to the housing on opposite sides of the outer crystals and resilient means fixed to the peripheries of the crystal sets, d. means rigidly connecting the inner crystal of one crystal set to the inner crystal of the other crystal set, e. a damping compound filling the housing and surrounding the crystal sets therein, and f. diaphragms enclosing the openings in the housing and contacting the compound.
Claim 8
Dependent Claim
136 words
A pressure transducer including: a. two sets of opposed dished piezoelectric crystals each comprising an inner crystal and an outer crystal, b. a housing enclosing the crystal sets and having opposed openings formed therein, c. means for detachably locating the crystal sets in the housing while permitting relative movement between the peripheries of the crystal sets and the interior of the housing, said locating means comprising resilient means fixed to the housing on opposite sides of the outer crystals and resilient means fixed to the peripheries of the crystal sets, d. means rigidly connecting the inner crystal of one crystal set to the inner crystal of the other crystal set, e. a damping compound filling the housing and surrounding the crystal sets therein, and f. diaphragms enclosing the openings in the housing and contacting the compound.
Claim 9
Dependent Claim
46 words
The pressure transducer according to claim 6 wherein each set of opposed dished piezoelectric crystals includes a metal disk positioned between the centers of the crystals and a ring of nonconductive cement extending around the crystal set for maintaining the peripheries of the crystals in contact.
Claim 10
Dependent Claim
44 words
The pressure transducer according to claim 7 wherein the crystal sets are mounted at spaced points within the housing and wherein the means rigidly connecting the inner crystals of the sets comprises a rigid member extending between and secured to the two inner crystals.
Claim 11
Dependent Claim
50 words
The pressure transducer according to claim 6 wherein the means for locating the crystal sets in the housing comprises a plurality of nubs positioned at spaced points around the peripheries of the crystal sets and a plurality of nubs fixed to the housing on opposite sides of the outer crystals.
Claim 12
Dependent Claim
34 words
The pressure transducer according to claim 6 wherein the housing comprises an outer case formed from an electrical insulating material and means forming an electrostatic shield around substantially the entire interior of the case.
Claim 13
Dependent Claim
42 words
The pressure transducer according to claim 6 further including means forming an electrical connection between the two outer crystals, means for forming electrical connections between the two inner crystals, and electrically conductive means extending from the electrical connections out of the housing.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-30 | 1977-01-29 | 1977-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-30 | 1981-01-29 | 1981-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-30 | 1985-01-29 | 1985-07-31 | $7700.00 | Window Closed / Lapsed |