US3702936A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dose rate dosimeter circuit
Assignee: United States Atomic Energy Commission
•
Filing: 1971-03-19
•
Granted: 1972-11-14
•
Expires: 1991-03-19
Abstract
Abstract The circuit uses the ionization characteristics of a GeigerMueller tube to provide equal energy charging pulses for an integrator. The integrator voltage is compared with a reference voltage to develop an alarm signal when the integrator voltage exceeds a preset level. Both the integrator and the circuit developing the reference voltage are connected to the same power supply so that power supply fluctuations have a minimum effect on the radiation level at which the alarm operates. A single variable resistance can be used to change the ranges over which the dosimeter operates.
Inventors
- 👤 Gerald L Erickson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:39
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/15
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
176 words
A dose rate dosimeter, including in combination, A GeigerMueller tube having a predetermined ionization period following an ionizing event and developing an ionizing current of said predetermined period in response to said ionizing event, a power supply, integration means having a first terminal directly d-c connected to said power supply and a second terminal, switch meAns having a normal off state and an on state and first resistor means directly d-c connected in series between said second terminal and said power supply, and circuit means d-c coupling said switch means to said Geiger-Mueller tube, said switch means being responsive to said ionizing current to be switched to said on state whereby charging current is supplied to said integration means for the duration of said ionizing current, the resistance of said switch means in said on state being sufficiently low so that the magnitude of said charging current is established by said resistance means, said integration means acting to integrate said charging current and to develop an output signal which is a function of said charging current.
Claim 2
Dependent Claim
176 words
A dose rate dosimeter, including in combination, A GeigerMueller tube having a predetermined ionization period following an ionizing event and developing an ionizing current of said predetermined period in response to said ionizing event, a power supply, integration means having a first terminal directly d-c connected to said power supply and a second terminal, switch meAns having a normal off state and an on state and first resistor means directly d-c connected in series between said second terminal and said power supply, and circuit means d-c coupling said switch means to said Geiger-Mueller tube, said switch means being responsive to said ionizing current to be switched to said on state whereby charging current is supplied to said integration means for the duration of said ionizing current, the resistance of said switch means in said on state being sufficiently low so that the magnitude of said charging current is established by said resistance means, said integration means acting to integrate said charging current and to develop an output signal which is a function of said charging current.
Claim 3
Dependent Claim
14 words
The dose rate dosimeter of claim 1 wherein, said first resistance means is variable.
Claim 4
Dependent Claim
76 words
The dose rate dosimeter of claim 2 wherein, said switch means is transistor means having a common electrode directly d-c connected to said power supply means, a control electrode directly d-c connected to said Geiger-Mueller tube for receiving said ionizing current so that a portion of said ionizing current flows through said control electrode to said common electrode and an output electrode, said first resistance means directly d-c connecting said output electrode to said integration means.
Claim 5
Dependent Claim
59 words
The dose rate dosimeter of claim 3 wherein, said transistor means is a single transistor having a base electrode directly d-c connected to said Geiger-Mueller tube, an emitter electrode directly d-c connected to said power supply and a collector electrode directly d-c connected to said first resistance means, and second resistance means coupled between said base and emitter electrodes.
Claim 6
Dependent Claim
34 words
The dose rate dosimeter of claim 4 further including, alarm means coupled to said integrating means, said alarm means being responsive to said output signal above a particular magnitude to develop an alarm signal.
Claim 7
Dependent Claim
52 words
The dose rate dosimeter of claim 5 wherein, said alarm means includes reference voltage means connected to said power supply to develop a reference voltage, and comparator means coupled to said reference voltage means and said integration means to develop said alarm signal with said output signal equal to said reference voltage.
Claim 8
Dependent Claim
27 words
The dose rate dosimeter of claim 6 wherein, the time constant of said reference voltage means is substantially equal to the time constant of said integration means.
References Cited (Backward Citations)
US2838680A
Cited
US2874305A
Cited
US2983818A
Cited
US2993995A
Cited
US3157789A
Cited
US3161774A
Cited
US3113212A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-11-14 | 1976-05-15 | 1976-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-11-14 | 1980-05-15 | 1980-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-11-14 | 1984-05-15 | 1984-11-14 | $7700.00 | Window Closed / Lapsed |