Patent US3790838A successfully refreshed from Google Patents.
US3790838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
X-ray tube target
Assignee: Varian Medical Systems Inc
•
Filing: 1973-02-27
•
Granted: 1974-02-05
•
Expires: 1993-02-27
Abstract
Abstract A target for anodes of X-ray tubes, particularly rotating anodes, having a compensated bimetallic structure which comprises a base matrix carrying coatings of selected material on both opposed surfaces for resisting distortion caused by high thermal energies.
Inventors
- 👤 C Baum
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:38
CPC Classifications
H; H01; H01J; H01J35/00; H01J35/02; H01J35/04; H01J35/08; H01J35/10; H01J35/108
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
107 words
An X-ray tube having an electron-emitting cathode and an anode positioned in the path of electrons from the cathode, said anode comprising a rotatable shaft, and a disclike target on the shaft and rotatable therewith, the target being disclike in shape and having a selected portion disposed to rotate through the path of the electrons, said target comprising a substrate having a known coefficient of thermal expansion and having on both opposed surfaces layers of material which has a higher coefficient of thermal expansion than the material of the substrate, and a metallic coating overlying the layer on the side of the target remote from the cathode.
Claim 2
Dependent Claim
107 words
An X-ray tube having an electron-emitting cathode and an anode positioned in the path of electrons from the cathode, said anode comprising a rotatable shaft, and a disclike target on the shaft and rotatable therewith, the target being disclike in shape and having a selected portion disposed to rotate through the path of the electrons, said target comprising a substrate having a known coefficient of thermal expansion and having on both opposed surfaces layers of material which has a higher coefficient of thermal expansion than the material of the substrate, and a metallic coating overlying the layer on the side of the target remote from the cathode.
Claim 3
Dependent Claim
30 words
An X-ray tube as set forth in claim 1 wherein said substrate is molybdenum and said layers are a metal selected from the group consisting of tungsten and tungsten-rhenium alloy.
Claim 4
Dependent Claim
15 words
An X-ray tube as set forth in claim 2 wherein said metallic coating is molybdenum.
Claim 5
Dependent Claim
15 words
An X-ray tube as set forth in claim 2 wherein said metallic coating is graphite.
Claim 6
Dependent Claim
30 words
An X-ray tube as set forth in claim 1 wherein said substrate is graphite and said layers are a metal selected from the group consisting of tungsten and tungsten-rhenium alloy.
Claim 7
Dependent Claim
15 words
An X-ray tube as set forth in claim 4 wherein said metallic coating is graphite.
Claim 8
Dependent Claim
15 words
An X-ray tube as set forth in claim 4 wherein said metallic coating is molybdenum.
Claim 9
Dependent Claim
29 words
An X-ray tube as set forth in claim 1 wherein the layer on the surface of the target facing the cathode is confined substantially to said selected portion thereof.
Claim 10
Dependent Claim
29 words
An X-ray tube as set forth in claim 1 wherein the layer on the surface of the target remote from the cathode varies in thickness in the radial direction.
Claim 11
Dependent Claim
36 words
An X-ray tube as set forth in claim 9 wherein the layer on the surface of the target remote from the cathode is substantially thicker in the area thereof opposite said selected portion of the target.
Claim 12
Dependent Claim
27 words
An X-ray tube as set forth in claim 1 wherein the layer more remote from the cathode is enclosed on both sides by material of the substrate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |