US3720202A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Instrument for measuring maximum expiratory flow rate
Assignee: Individual
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Filing: 1971-10-05
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Granted: 1973-03-13
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Expires: 1991-10-05
Abstract
Abstract An instrument for measuring maximum expiratory flow rate having a vertically disposed cylinder with a plurality of equal sized orifices distributed along its length, a floating piston disposed in the cylinder having a guide rod passing through a closure on the top of the cylinder, a holdback clip mounted on the cylinder closure and operatively engaging the guide rod to prevent the guide rod from moving downwardly once the piston has moved upwardly in the cylinder and a suitable, flexible air tube having a mouthpiece at one end and connected in open communication with the bottom of the cylinder at its other end. The instrument can also be provided with a check valve at the lower end of the cylinder to prevent backflow of air through the air tube and adjustable port means adjacent the base of the cylinder to adjust the range of the instrument.
Inventors
- 👤 J Cleary
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:50
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/08; A61B5/087; A61B5/0871
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
157 words
Apparatus for measuring a patients maximum expiratory flow rate, comprising; a cylinder having a central bore of equal diameter throughout its length, one end thereof closed and a plurality of equal-diameter orifices passing through the wall of said cylinder and spaced along the length of said cylinder; piston means disposed in said central bore of said cylinder; guide rod means having one end thereof attached to said piston and slidably passing through said closed end of said cylinder; holdback means mounted on said adjacent said closed end of said cylinder and releasably holding said guide rod to prevent said guide rod and piston from sliding toward the open end of said cylinder while permitting free movement of said guide rod and piston toward said closed end of said cylinder; and air tube means having one end connected in open communication with said open end of said cylinder and the other end provided with a sanitary mouth piece.
Claim 2
Dependent Claim
157 words
Apparatus for measuring a patients maximum expiratory flow rate, comprising; a cylinder having a central bore of equal diameter throughout its length, one end thereof closed and a plurality of equal-diameter orifices passing through the wall of said cylinder and spaced along the length of said cylinder; piston means disposed in said central bore of said cylinder; guide rod means having one end thereof attached to said piston and slidably passing through said closed end of said cylinder; holdback means mounted on said adjacent said closed end of said cylinder and releasably holding said guide rod to prevent said guide rod and piston from sliding toward the open end of said cylinder while permitting free movement of said guide rod and piston toward said closed end of said cylinder; and air tube means having one end connected in open communication with said open end of said cylinder and the other end provided with a sanitary mouth piece.
Claim 3
Dependent Claim
157 words
Apparatus for measuring a patients maximum expiratory flow rate, comprising; a cylinder having a central bore of equal diameter throughout its length, one end thereof closed and a plurality of equal-diameter orifices passing through the wall of said cylinder and spaced along the length of said cylinder; piston means disposed in said central bore of said cylinder; guide rod means having one end thereof attached to said piston and slidably passing through said closed end of said cylinder; holdback means mounted on said adjacent said closed end of said cylinder and releasably holding said guide rod to prevent said guide rod and piston from sliding toward the open end of said cylinder while permitting free movement of said guide rod and piston toward said closed end of said cylinder; and air tube means having one end connected in open communication with said open end of said cylinder and the other end provided with a sanitary mouth piece.
Claim 4
Dependent Claim
157 words
Apparatus for measuring a patients maximum expiratory flow rate, comprising; a cylinder having a central bore of equal diameter throughout its length, one end thereof closed and a plurality of equal-diameter orifices passing through the wall of said cylinder and spaced along the length of said cylinder; piston means disposed in said central bore of said cylinder; guide rod means having one end thereof attached to said piston and slidably passing through said closed end of said cylinder; holdback means mounted on said adjacent said closed end of said cylinder and releasably holding said guide rod to prevent said guide rod and piston from sliding toward the open end of said cylinder while permitting free movement of said guide rod and piston toward said closed end of said cylinder; and air tube means having one end connected in open communication with said open end of said cylinder and the other end provided with a sanitary mouth piece.
Claim 5
Dependent Claim
23 words
Apparatus in accordance with claim 1 wherein the cylinder is transparent and calibrated to indicate the piston of the piston within said cylinder.
Claim 6
Dependent Claim
34 words
Apparatus in accordance with claim 1 wherein the holdback means is a spring type clip having an aperture therethrough which the guide rod passes and is bent toward the closed end of the cylinder.
Claim 7
Dependent Claim
33 words
Apparatus in accordance with claim 1 wherein the open end of the cylinder is mounted in a base and said base has an air passage therein connecting said cylinder and the air tube.
Claim 8
Dependent Claim
43 words
Apparatus in accordance with claim 4 wherein the air passage in the base has a check valve formed therein to prevent Passage of air from the cylinder to the air tube while permitting passage of air from said air tube to said cylinder.
Claim 9
Dependent Claim
34 words
Apparatus in accordance with claim 5 wherein the check valve comprises a valve seat formed in the base adjacent the open end of the cylinder and a free floating ball disposed above said seat.
Claim 10
Dependent Claim
30 words
Apparatus in accordance with claim 1 wherein the cylinder has operatively associated therewith means for changing the amount of air which can pass out of said cylinder below the piston.
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) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |