US3741199A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Clinical blood pressure measuring apparatus
Assignee: Wilkinson Sword Ltd
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Filing: 1971-09-29
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Granted: 1973-06-26
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Expires: 1991-09-29
Abstract
Abstract A pair of inflatable cuffs, for encircling a patient''s limb, are connected to a reservoir and pumped up above the systolic pressure. The reservoir and cuff pressure is allowed to leak controllably and, via a bellows arrangement, the falling pressure turns a pivotal arm whose distal end carries an electric motor. A recording pen extends radially from the motor shaft and moves along a pressure axis on a chart as the arm pivots. When the falling pressure reaches the systolic level, blood pulsations generate pneumatic pulses in the cuffs which are electrically detected by an anomometer and cause the motor shaft to oscillate, providing transverse pen movement. Such oscillations diminish when the falling pressure reaches the diastolic level.
Inventors
- 👤 J Sharpe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:41
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/021; A61B5/022; Y; Y10; Y10S; Y10S128/00; Y10S128/90
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
234 words
Apparatus for automatic clinical measurement of systolic and diastolic blood pressure, comrising cuff means for encircling part of the patient where the blood pressure is to be determined, reservoir means, a pressure connection between the reservoir means and the cuff means, pump means connected to the reservoir means for raising the pressure in the reservoir means and in the cuff means to above the systolic level, means defining a pressure leak in communication with the reservoir means for allowing the pressure in the reservoir means and cuff means to fall progressively, a blood pressure indicating output element, means mounting the output element for movement in two transverse directions, first pressure-responsive means having a pressure input connected to the reservoir means to sense the falling pressure in the reservoir means and the cuff means and an output at which is produced a corresponding output signal which is connected to move the output element correspondingly in one of said directions, and second pressure-responsive means mounted between the reservoir means and the cuff means to sense pressure variations in the cuff means caused by blood pulsations in said part of the patient as the cuff pressure falls having an output at which is developed a corresponding output signal which is connected to oscillate the output element in the other one of said directions, said output element indicating the result of said signals as readings of blood pressure.
Claim 2
Dependent Claim
234 words
Apparatus for automatic clinical measurement of systolic and diastolic blood pressure, comrising cuff means for encircling part of the patient where the blood pressure is to be determined, reservoir means, a pressure connection between the reservoir means and the cuff means, pump means connected to the reservoir means for raising the pressure in the reservoir means and in the cuff means to above the systolic level, means defining a pressure leak in communication with the reservoir means for allowing the pressure in the reservoir means and cuff means to fall progressively, a blood pressure indicating output element, means mounting the output element for movement in two transverse directions, first pressure-responsive means having a pressure input connected to the reservoir means to sense the falling pressure in the reservoir means and the cuff means and an output at which is produced a corresponding output signal which is connected to move the output element correspondingly in one of said directions, and second pressure-responsive means mounted between the reservoir means and the cuff means to sense pressure variations in the cuff means caused by blood pulsations in said part of the patient as the cuff pressure falls having an output at which is developed a corresponding output signal which is connected to oscillate the output element in the other one of said directions, said output element indicating the result of said signals as readings of blood pressure.
Claim 3
Dependent Claim
33 words
Apparatus according to claim 1, in which the output element comprises a recording medium marking element, and including means for supporting a recording medium in juxtaposition with the output element for marking thereby.
Claim 4
Dependent Claim
43 words
Apparatus according to claim 1, in which the means mounting the output element comprises an arm movably supported on the base, and an electric motor rigidly attached to the arm and having an output shaft to which the output element is attached. the
Claim 5
Dependent Claim
60 words
Apparatus according to claim 3, in which one of the said pressure-responsive means develops a mechanical output and includes means connected to the arm for moving the arm in dependence on th mechanical output, and in which the other of the pressure responsive means produces an electrical output and includes means connecting the electrical output to energise the said motor.
Claim 6
Dependent Claim
103 words
Apparatus according to claim 3, in which: the first pressure responsive means comprises means defining a container having movable wall means and in pressure communication with the reservoir means, and means transmitting th movement of the wall means to the arm, and the second pressure responsive means comprises temperature-sensitive electrical resistance means mounted in the pressure connection between the cuff means and the reservoir means whereby to change its electrical resistance in response to the said blood pulsations, means operative to develop electrical signals in response to the changes in resistance, an means energising the electric motor in dependence on th electrical signals.
Claim 7
Dependent Claim
45 words
Apparatus according to claim 5, in which the cuff means comprises two separate cuffs, and in which the said pressure connection comprises respective pressure lines connecting the cuffs to the reservoir means, the temperature-sensitive variable electrical resistance means being mounted in one said pressure line.
Claim 8
Dependent Claim
71 words
Apparatus according to claim 4, in which the said means for energising the electric moTor in dependence on the electrical output comprises means producing a feedback signal in dependence on the instantaneous position of th motor shaft, and a servo amplifier responsive to the said electrical output and to the feedback signal and operative to amplify the difference, if any, between them whereby to produce a power signal for the motor.
Claim 9
Dependent Claim
80 words
Apparatus according to claim 5, in which the said arm is part of a pivoted first-order lever, and in which the said electric motor is mounted adjacent one distal end of the lever with its shaft rotatable about an axis parallel to the pviotal axis of the lever, and in which the movement of the said movable wall means is applied to a point on th lever on the opposite side of the pivotal axis thereof to the electric motor.
Claim 10
Dependent Claim
10 words
Apparatus according to claim 2, incorporated in a hand-portable container.
Claim 11
Dependent Claim
113 words
Apparatus according to claim 1, in which the means defining the pressure leak comprises a valve controlling a fluid path between atmosphere and a reservoir means, the said valve comprising means defining a tubular passageway leading from the inside to the outside of the reservoir means, means terminating each end of the passageway in through holes of lesser cross-sectional area than the passageway, one of the holes being off the centre line along the passageway, and a ball loosely mounted in the passageway so as to be forced by the pressure in the reservoir means to sit only partially over the entrance to the hole leading to the outside of the reservoir means.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |