US3868679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Blood pressure amplifier with zero balancing means
Assignee: GE Medical Systems Information Technologies Inc
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Filing: 1973-10-09
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Granted: 1975-02-25
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Expires: 1993-10-09
Abstract
Abstract An amplifier for the signal from a blood pressure transducer is balanced to zero reference by introducing its offset signal and an offset balancing or correction signal to a summing amplifier. The resulting difference signal is fed to a comparator. A trigger signal at the start of balancing starts some digital counters counting. The digital output signal from the counters is converted to an analog correction signal which is fed to the summing amplifier. When the offset signal magnitude crosses the analog correction signal, the comparator switches and stops the counting. The analog correction signal is then available for use by the amplifier when blood pressure is actually measured.
Inventors
- 👤 Harold N Arneson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:22
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/021; A61B5/0215; H; H03; H03F; H03F3/00; H03F3/45; H03F3/45071; H03F3/45479; H03M; H03M1/00; H03M1/12; H03M1/48
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
328 words
Means for correcting a device that responds to signals from a blood pressure transducer for the offset signal of the transducer, comprising: a. summing amplifier means having an output and respective inputs for a correction signal and a signal from said transducer, b. comparator means having an output and also having at least two inputs one of which is coupled with said amplifier means output, the output of said comparator means changing state in response to a correction signal and reference voltage signal to said summing means inputs becoming substantially equal, and means for supplying a reference voltage signal to an input to said comparator means, c. a source of pulses having a constant repetition rate, d. pulse counting means coupled with said source, said counting means being constructed and arranged for producing a digital signal corresponding in magnitude with the number of pulses counted and which signal increases in magnitude at a substantially constant rate, e. means for activating said counting means when production of a correction signal is desired, f. means for converting said digital signal representative of the count by said counting means to an analog signal and means for storing said analog signal which constitutes said correction signal, g. means for coupling said correction signal to its summing means input, h. means for deactivating said counting means in response to said comparator means output changing state, i. gate means interposed between said pulse source and said counting means, j. switch means for controlling said gate means, k. one-shot multivibrator means for controlling said switch means and for clearing said counting means, said counting means being cleared when said multivibrator means is being switched to enable gating of pulses through said gate means when said multivibrator is in another of its states, l. said switch means also responding to said comparator means changing state by disabling said gate means from providing pulses to saiD counting means to thereby effect said deactivating of said counting means.
Claim 2
Dependent Claim
328 words
Means for correcting a device that responds to signals from a blood pressure transducer for the offset signal of the transducer, comprising: a. summing amplifier means having an output and respective inputs for a correction signal and a signal from said transducer, b. comparator means having an output and also having at least two inputs one of which is coupled with said amplifier means output, the output of said comparator means changing state in response to a correction signal and reference voltage signal to said summing means inputs becoming substantially equal, and means for supplying a reference voltage signal to an input to said comparator means, c. a source of pulses having a constant repetition rate, d. pulse counting means coupled with said source, said counting means being constructed and arranged for producing a digital signal corresponding in magnitude with the number of pulses counted and which signal increases in magnitude at a substantially constant rate, e. means for activating said counting means when production of a correction signal is desired, f. means for converting said digital signal representative of the count by said counting means to an analog signal and means for storing said analog signal which constitutes said correction signal, g. means for coupling said correction signal to its summing means input, h. means for deactivating said counting means in response to said comparator means output changing state, i. gate means interposed between said pulse source and said counting means, j. switch means for controlling said gate means, k. one-shot multivibrator means for controlling said switch means and for clearing said counting means, said counting means being cleared when said multivibrator means is being switched to enable gating of pulses through said gate means when said multivibrator is in another of its states, l. said switch means also responding to said comparator means changing state by disabling said gate means from providing pulses to saiD counting means to thereby effect said deactivating of said counting means.
Claim 3
Dependent Claim
308 words
Means for correcting a device that responds to signals from a blood pressure transducer for the unbalance signal therefrom prior to use of the transducer for sensing blood pressure, comprising: a. summing amplifier means having an output and having an input for a signal from the transducer and an input for a signal to compensate said unbalance signal, b. comparator means having an input controlled by the signal from the output of said amplifier means and having an output, the output of said comparator means changing state when said unbalance compensating signal and said transducer signal are substantially equal, c. a source of pulses having a constant repetition rate, d. pulse counting means responsive to receiving pulses by producing a digital signal corresponding with the number of pulses counted, said signal changing at a substantially constant rate during counting, e. means for converting said digital signal to an analog signal and storage means for said signal, said analog signal constituting said unbalance compensating signal, means for coupling said analog signal to said summing amplifier means input, f. gate means coupling said pulse source with said counting means, g. means for resetting said counting means when production of a balancing signal is desired, h. means for enabling said gate means to provide pulses to said counting means, i. means for disabling said gate means in response to said comparator means changing state, whereby to effect storage of said analog signal for continuous unbalance compensation during ensuing signals from said transducer, j. said summing amplifier means comprising a differential amplifier having said unbalance compensating signal and said transducer signal inputs, and k. second signal amplifier means interposed between said differential amplifier and said comparator means, the output signal of said second amplifier means being functionally related to the blood pressure indicative signal from said transducer means corrected for said unbalance.
Claim 4
Dependent Claim
308 words
Means for correcting a device that responds to signals from a blood pressure transducer for the unbalance signal therefrom prior to use of the transducer for sensing blood pressure, comprising: a. summing amplifier means having an output and having an input for a signal from the transducer and an input for a signal to compensate said unbalance signal, b. comparator means having an input controlled by the signal from the output of said amplifier means and having an output, the output of said comparator means changing state when said unbalance compensating signal and said transducer signal are substantially equal, c. a source of pulses having a constant repetition rate, d. pulse counting means responsive to receiving pulses by producing a digital signal corresponding with the number of pulses counted, said signal changing at a substantially constant rate during counting, e. means for converting said digital signal to an analog signal and storage means for said signal, said analog signal constituting said unbalance compensating signal, means for coupling said analog signal to said summing amplifier means input, f. gate means coupling said pulse source with said counting means, g. means for resetting said counting means when production of a balancing signal is desired, h. means for enabling said gate means to provide pulses to said counting means, i. means for disabling said gate means in response to said comparator means changing state, whereby to effect storage of said analog signal for continuous unbalance compensation during ensuing signals from said transducer, j. said summing amplifier means comprising a differential amplifier having said unbalance compensating signal and said transducer signal inputs, and k. second signal amplifier means interposed between said differential amplifier and said comparator means, the output signal of said second amplifier means being functionally related to the blood pressure indicative signal from said transducer means corrected for said unbalance.
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) | 1978-02-24 | 1978-08-26 | 1979-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-24 | 1982-08-26 | 1983-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-24 | 1986-08-26 | 1987-02-25 | $7700.00 | Window Closed / Lapsed |