US3905353A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Blood pressure apparatus
Assignee: Medical Monitors Inc
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Filing: 1974-02-28
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Granted: 1975-09-16
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Expires: 1994-02-28
Abstract
Abstract A closed air system includes a reservoir and inflatable cuff arranged to block off blood flow in a portion of a person''s circulatory system when inflated by air from the reservoir. An outlet tube connected to a pump passes air from the reservoir to the inflatable cuff and a single valve in a return tube from the cuff to the reservoir permits pressure to be gradually decreased. A pressure transducer provides a feedback signal to the valve to control the rate of pressure drop and maintain it substantially constant all to the end that a doctor can more quickly and accurately take a patient''s blood pressure.
Inventors
- 👤 Abraham Lichowsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:13
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/021; A61B5/022
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
317 words
A blood pressure apparatus comprising, in combination: a. a pneumatically sealed reservoir having outlet and inlet tubes communicating with its interior; b. inflatable pressure means exterior of said reservoir connected to said tubes and arranged to block off blood flow in a portion of a person''s circulatory system when inflated to a given pressure; c. pump means connected to the outlet tube for pumping air from said reservoir into said inflatable pressure means when energized; d. means for energizing said pump means; e. an electrically controlled valve connected to said inlet tube for passing air from said inflatable pressure means back into said reservoir in a controlled manner after said given pressure is reached to cause a continuous gradual decrease in the pressure; f. pressure transducer means responsive to pressure in said inflatable pressure means for generating an analog signal constituting a function of said pressure; and g. feedback means connected between said pressure transducer means and said electrically controlled valve, said feedback means including: 1. means responsive to said analog signal to provide a a singal level proportional to the slope of the analog signal generated in response to said gradual decrease in pressure; 2. a reference signal level generating means; and, 3. means for generating an error signal in response to any difference in said signal level proportional to the slope of said analog signal, and said reference signal level, for controlling the action of said valve to correct any deviation in said slope from a desired constant value to thereby provide a given constant rate of pressure drop in said inflatable pressure means, whereby a doctor can energize said pump means to close off said blood flow when said given pressure is attained and then listen to acoustic pulses with a stethoscope to determine systolic and diastolic blood pressure with assurance that the rate of pressure decrease in said inflatable pressure means remains contant.
Claim 2
Dependent Claim
317 words
A blood pressure apparatus comprising, in combination: a. a pneumatically sealed reservoir having outlet and inlet tubes communicating with its interior; b. inflatable pressure means exterior of said reservoir connected to said tubes and arranged to block off blood flow in a portion of a person''s circulatory system when inflated to a given pressure; c. pump means connected to the outlet tube for pumping air from said reservoir into said inflatable pressure means when energized; d. means for energizing said pump means; e. an electrically controlled valve connected to said inlet tube for passing air from said inflatable pressure means back into said reservoir in a controlled manner after said given pressure is reached to cause a continuous gradual decrease in the pressure; f. pressure transducer means responsive to pressure in said inflatable pressure means for generating an analog signal constituting a function of said pressure; and g. feedback means connected between said pressure transducer means and said electrically controlled valve, said feedback means including: 1. means responsive to said analog signal to provide a a singal level proportional to the slope of the analog signal generated in response to said gradual decrease in pressure; 2. a reference signal level generating means; and, 3. means for generating an error signal in response to any difference in said signal level proportional to the slope of said analog signal, and said reference signal level, for controlling the action of said valve to correct any deviation in said slope from a desired constant value to thereby provide a given constant rate of pressure drop in said inflatable pressure means, whereby a doctor can energize said pump means to close off said blood flow when said given pressure is attained and then listen to acoustic pulses with a stethoscope to determine systolic and diastolic blood pressure with assurance that the rate of pressure decrease in said inflatable pressure means remains contant.
Claim 3
Dependent Claim
7 words
a reference signal level generating means; and,
Claim 4
Dependent Claim
7 words
a reference signal level generating means; and,
Claim 5
Dependent Claim
28 words
An apparatus according to claim 1, in which said pump means is positioned within said reservoir so that it is protected from dirt and sound therefrom is muffled.
Claim 6
Dependent Claim
113 words
means for generating an error signal in response to any difference in said signal level proportional to the slope of said analog signal, and said reference signal level, for controlling the action of said valve to correct any deviation in said slope from a desired constant value to thereby provide a given constant rate of pressure drop in said inflatable pressure means, whereby a doctor can energize said pump means to close off said blood flow when said given pressure is attained and then listen to acoustic pulses with a stethoscope to determine systolic and diastolic blood pressure with assurance that the rate of pressure decrease in said inflatable pressure means remains contant.
Claim 7
Dependent Claim
113 words
means for generating an error signal in response to any difference in said signal level proportional to the slope of said analog signal, and said reference signal level, for controlling the action of said valve to correct any deviation in said slope from a desired constant value to thereby provide a given constant rate of pressure drop in said inflatable pressure means, whereby a doctor can energize said pump means to close off said blood flow when said given pressure is attained and then listen to acoustic pulses with a stethoscope to determine systolic and diastolic blood pressure with assurance that the rate of pressure decrease in said inflatable pressure means remains contant.
Claim 8
Dependent Claim
20 words
An apparatus according to claim 1, including pressure display means for visually indicating the pressure in said inflatable pressure means.
Claim 9
Dependent Claim
23 words
An apparatus according to claim 1, in which said pump means includes means, when energized, to build up pressure at a desired rate.
Claim 10
Dependent Claim
34 words
An apparatus according to claim 1, including means connected to said electrically controlled valve and responsive to energization of said pump means to automatically hold said valve closed while said pump means is energized.
References Cited (Backward Citations)
US3508537A
Cited
US3527204A
Cited
US3550582A
Cited
US3552381A
Cited
US3654915A
Cited
US3779235A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |