US3633029A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulsed x-ray control system with improved film darkening
Assignee: CGR Medical Corp
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Filing: 1970-10-27
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Granted: 1972-01-04
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Expires: 1990-10-27
Abstract
Abstract A circuit for use with a grid pulse X-ray tube which is operated at its maximum rated kv. and ma. The circuit provides more film darkening than would otherwise be possible when the X-ray tube is operated under such a maximum load. The circuit includes a filter which converts the output of the high-tension transformer from a sine wave to substantially a square wave which is then fed to the input of the X-ray tube. The pulsing of the grid is controlled by other circuits in such a way that the X-ray tube conducts symmetrically about the midpoint of the sine wave. Such precise timing of the grid pulse to initiate conductivity of the X-ray tube aids the filter in its function of providing a square wave to the X-ray tube input.
Inventors
- 👤 Philip A Duffy Jr
- 👤 Melvin P Siedband
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:44
CPC Classifications
H; H05; H05G; H05G1/00; H05G1/08; H05G1/10; H05G1/22
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
147 words
In combination with an X-ray tube, a voltage source operably connected to said X-ray tube for causing said X-ray tube to generate X-radiation, the output of said voltage source being substantially in the form of a sine wave, means for changing said X-radiation into photoemissions, a camera, and film in said camera operable to record a permanent picture of the information provided by said photoemissions; conversion means operable to change said sine wave substantially to a square wave, said conversion means including impedance means disposed intermediate said voltage source and said X-ray tube, said conversion means further including delay means disposed intermediate said camera and said X-ray tube for causing said X-ray tube to provide Xradiation for a selected period of time and for causing said period of time to occur substantially symmetrically with respect to the midpoint of at least one-half cycle of said sine wave.
Claim 2
Dependent Claim
147 words
In combination with an X-ray tube, a voltage source operably connected to said X-ray tube for causing said X-ray tube to generate X-radiation, the output of said voltage source being substantially in the form of a sine wave, means for changing said X-radiation into photoemissions, a camera, and film in said camera operable to record a permanent picture of the information provided by said photoemissions; conversion means operable to change said sine wave substantially to a square wave, said conversion means including impedance means disposed intermediate said voltage source and said X-ray tube, said conversion means further including delay means disposed intermediate said camera and said X-ray tube for causing said X-ray tube to provide Xradiation for a selected period of time and for causing said period of time to occur substantially symmetrically with respect to the midpoint of at least one-half cycle of said sine wave.
Claim 3
Dependent Claim
79 words
The combination of claim 1 wherein said delay means comprises pulse-generating means including contact means actuated by said camera for generating at least one pulse during the occurrence of said at least one-half cycle; said pulse-generating means further including holding and conducting means, said holding and conducting means being operable to delay said at least one pulse for a second selected period of time and for subsequently conducting said at least one pulse for said selected period of time.
Claim 4
Dependent Claim
53 words
The combination of claim 1 wherein said X-ray tube draws a selected aMount of power, and said impedance means is connected to said voltage source and said X-ray tube, the magnitude of said impedance means being such that it supplies a selected portion of said selected amount of power to said X-ray tube.
Claim 5
Dependent Claim
54 words
The combination of claim 3 wherein said impedance means includes capacitor means, first resistive means, and second resistive means; a first conducting path including said first resistive means for charging said capacitor means and a second conducting path including said second resistive means for permitting said capacitor means to discharge through said X-ray tube.
Claim 6
Dependent Claim
19 words
The combination of claim 4 wherein said second conducting path includes a selected portion of said first resistive means.
Claim 7
Dependent Claim
59 words
The combination of claim 1 wherein said X-ray tube includes an anode, a cathode and a grid; bias voltage means; means connecting said bias voltage means to said grid; switching means connected to said bias voltage means for rendering said bias voltage means ineffective, said switching means being actuated by said delay means for said selected period of time.
Claim 8
Dependent Claim
55 words
The combination of claim 6 wherein said grid bias means normally renders said X-ray tube nonconductive; said delay means includes a pulse-generating means for generating at least one pulse during the occurrence of said at least one-half cycle; said switching means being actuated by said at least one pulse for said selected period of time.
Claim 9
Dependent Claim
15 words
The combination of claim 6 wherein said switching means includes a plurality of cascade-connected transistors.
Claim 10
Dependent Claim
33 words
The combination of claim 6 wherein said switching means includes at least one electronic switch having an input terminal and an output terminal, said terminals being operably connectable across said bias voltage supply.
Claim 11
Dependent Claim
30 words
The combination of claim 1 wherein said camera includes a shutter; said delay means includes means for synchronizing generation of X-radiation by said X-ray tube with operation of said shutter.
Claim 12
Dependent Claim
129 words
In combination with an X-ray tube, a voltage source operably connected to said X-ray tube for causing said X-ray tube to generate X-radiation, the output of said voltage source being substantially in the form of a sine wave, and film means for recording a permanent picture of the information provided by said X-radiation; conversion means operable to change said sine wave substantially to a square wave, said conversion means including impedance means disposed intermediate said voltage source and said X-ray tube, said conversion means further including delay means operable to cause said X-ray tube to generate said X-radiation for a selected period of time and for causing said period of time to occur substantially symmetrically with respect to the midpoint of at least one-half cycle of said sine wave.
Claim 13
Dependent Claim
129 words
In combination with an X-ray tube, a voltage source operably connected to said X-ray tube for causing said X-ray tube to generate X-radiation, the output of said voltage source being substantially in the form of a sine wave, and film means for recording a permanent picture of the information provided by said X-radiation; conversion means operable to change said sine wave substantially to a square wave, said conversion means including impedance means disposed intermediate said voltage source and said X-ray tube, said conversion means further including delay means operable to cause said X-ray tube to generate said X-radiation for a selected period of time and for causing said period of time to occur substantially symmetrically with respect to the midpoint of at least one-half cycle of said sine wave.
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) | 1975-01-03 | 1975-07-05 | 1976-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-03 | 1979-07-05 | 1980-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-03 | 1983-07-05 | 1984-01-04 | $7700.00 | Window Closed / Lapsed |