US3599033A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for simultaneous display of ecg and heart rate
Assignee: HP Inc
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Filing: 1969-09-22
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Granted: 1971-08-10
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Expires: 1989-09-22
Abstract
Abstract A cathode ray tube system receives a cardiac signal and simultaneously produces two displays corresponding to the analog form of the cardiac signal and the heartbeat rate. The displays are generated by separate horizontal and vertical deflection circuits which are alternately switched to drive the cathode ray tube beam. The display of the heart rate is a picture of a bar graph, the length of which changes to indicate the moving average of the heart rate. The bar graph is produced by generating a horizontal line raster and selectively blanking and unblanking the cathode ray tube. High and low limit markers and alarm circuitry associated with the bar graph display operate to indicate when the heart rate moves outside a preset range.
Inventors
- 👤 Robert L Stettiner
- 👤 William F Craven
- 👤 Dana C Finlayson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:05
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/024; A61B5/0245; A61B5/02455; A61B5/24; A61B5/316; A61B5/318; A61B5/339
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
269 words
A system for driving a cathode ray tube to display both a repetitive analog signal and the recurrence rate of said signal comprising: means for tracing said analog signal including: a first horizontal deflection circuit including ramp generator means for deflecting the beam of said cathode ray tube horizontally at a predetermined rate; a first vertical deflection circuit responsive to the magnitude of said analog signal; means for producing a bar graph indicative of the recurrence rate of said analog signal including: a second horizontal deflection circuit and a second vertical deflection circuit each including ramp generator means for deflecting said beam, thereby to produce a line raster; means responsive to said analog signal for producing a tachometer signal corresponding to the recurrence rate of said analog signal; means for comparing the magnitudes of said tachometer signal and the ramp signal from the ramp generator means of said second horizontal deflection circuit, said comparing means being operable to produce first and second output signals when the magnitude of said tachometer signal is respectively greater and less than that of said ramp signal; and means for gating said first and second output signals to said cathode ray tube to respectively blank and unblank said beam; means for controlling the position of said beam to simultaneously display said analog signal and said bar graph, said controlling means including: horizontal chopper means fOr alternately coupling said first and second horizontal deflection circuits to said cathode ray tube; and vertical chopper means synchronized with said horizontal chopper means for alternately coupling said first and second vertical deflection circuits to said cathode ray tube.
Claim 2
Independent Claim
269 words
A system for driving a cathode ray tube to display both a repetitive analog signal and the recurrence rate of said signal comprising: means for tracing said analog signal including: a first horizontal deflection circuit including ramp generator means for deflecting the beam of said cathode ray tube horizontally at a predetermined rate; a first vertical deflection circuit responsive to the magnitude of said analog signal; means for producing a bar graph indicative of the recurrence rate of said analog signal including: a second horizontal deflection circuit and a second vertical deflection circuit each including ramp generator means for deflecting said beam, thereby to produce a line raster; means responsive to said analog signal for producing a tachometer signal corresponding to the recurrence rate of said analog signal; means for comparing the magnitudes of said tachometer signal and the ramp signal from the ramp generator means of said second horizontal deflection circuit, said comparing means being operable to produce first and second output signals when the magnitude of said tachometer signal is respectively greater and less than that of said ramp signal; and means for gating said first and second output signals to said cathode ray tube to respectively blank and unblank said beam; means for controlling the position of said beam to simultaneously display said analog signal and said bar graph, said controlling means including: horizontal chopper means fOr alternately coupling said first and second horizontal deflection circuits to said cathode ray tube; and vertical chopper means synchronized with said horizontal chopper means for alternately coupling said first and second vertical deflection circuits to said cathode ray tube.
Claim 3
Dependent Claim
111 words
The system of claim 1 further including means for producing display markers to indicate low and high limits of a desired range for said bar graph, said marker-producing means comprising: means for providing adjustable, predetermined low and high-potential levels; means for comparing the magnitude of said ramp signal with said low and high potential levels; means responsive to said last-named comparing means for generating low and high marker pulses in sequence when the magnitude of said ramp signal is equal to said low and high potential levels, respectively; and means for gating said marker pulses to said cathode ray tube to unblank said beam when it is tracing said line raster.
Claim 4
Dependent Claim
95 words
The system of claim 2 further including means for limiting said bar graph to a predetermined width which is less than the width of said markers, said limiting means comprising: means for providing predetermined low and high-potential levels; means for comparing said last named low and high-potential levels with the ramp signal from the ramp generator of the second vertical deflection circuit; and means responsive to said comparing means for blanking the cathode ray tube beam when said last-named ramp signal is less than or greater than said last-named low and high potential levels, respectively.
Claim 5
Dependent Claim
28 words
The system of claim 2 further including means for producing alarm signals when said tachometer signal is less than and greater than said low and high-potential levels, respectively.
Claim 6
Dependent Claim
77 words
The system of claim 1, wherein said means for producing said tachometer signal includes: means for filtering out interference signals from said repetitive analog signal; full-wave rectifier means responsive to said filtering means; means responsive to said full-wave rectifier means for detecting the peaks of said repetitive analog signal; pulse-generating means for producing output pulses in response to the peaks detected by said peak-detecting means; and means for averaging said output pulses to produce said tachometer signal.
Claim 7
Dependent Claim
48 words
The system of claim 5, wherein said peak detecting means includes: means for averaging a predetermined number of the repetitive portions of the rectified analog signal; and means for producing an output signal when said analog signal is greater than the averaged signal from said last-named averaging means.
Claim 8
Dependent Claim
95 words
The system of claim 1, said ramp generator means of said first horizontal deflection circuit being operable to produce ramp signals having a predetermined duty cycle t1; said ramp generator means of said second horizontal deflection circuit being operable to produce ramp signals having a predetermined duty cycle t2 which is substantially less than t1; and said controlling means including clock pulse-generating means for simultaneously driving said horizontal and vertical chopper means, said clock pulse generating means being operable to produce clock pulses separated by a time interval t3 which is intermediate t1 and t2.
Claim 9
Dependent Claim
51 words
The system of claim 7 further including pulse-generating means responsive to said clock pulses for triggering the ramp generator of said second horizontal deflection circuit and for blanking said cathode ray tube beam when said horizontal and vertical chopper means switch between said first and second horizontal and vertical deflection circuits.
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) | 1974-08-09 | 1975-02-08 | 1975-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-09 | 1979-02-08 | 1979-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-09 | 1983-02-08 | 1983-08-10 | $7700.00 | Window Closed / Lapsed |