US3621876A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-sealing chalk valve
Assignee: Individual
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Filing: 1970-01-19
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Granted: 1971-11-23
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Expires: 1990-01-19
Abstract
Abstract A cup-shaped molded rubber valve body having a diaphragm with a diametric slit, said valve body being forced into an aperture in a rigid chalk confining shell, and expanding into and around the edges of said aperture, said shell embodying a dihedral seat bordering said aperture which bends said valve about an axis at a right angle to said slit, thereby biasing the lips of said slit together causing said valve to close when a chalk-injecting nozzle has been withdrawn from said valve.
Inventors
- 👤 Robert K Campbell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:41
CPC Classifications
F; F16; F16K; F16K15/00; F16K15/14; F16K15/144; F16K15/147; E; E04; E04G; E04G21/00; E04G21/14; E04G21/16; E04G21/18; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7879; Y10T137/788; Y10T137/7882
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
155 words
In combination: a cup-shaped molded rubber valve body having a mounting rim and a bottom providing a diaphragm with a diametric slit dividing said diaphragm into two juxtaposed lips, an external annular groove being formed peripherally in said rim to provide upper and lower flanges bordering said groove; a rigid wall having a circular aperture into which said body is adapted to be pressed to mount said body in said aperture, said groove concentrically closely fitting said aperture when said body is so mounted; said wall being provided with surfaces bordering said aperture which operate when said body is inserted in said aperture to conform therewith, to bend said body toward said slit about a diametral axis disposed crosswise of said slit to bias said lips into face-to-face pressural contact with each other to cause said slit to be positively closed by said forces when an element separating said lips is removed from between these.
Claim 2
Dependent Claim
155 words
In combination: a cup-shaped molded rubber valve body having a mounting rim and a bottom providing a diaphragm with a diametric slit dividing said diaphragm into two juxtaposed lips, an external annular groove being formed peripherally in said rim to provide upper and lower flanges bordering said groove; a rigid wall having a circular aperture into which said body is adapted to be pressed to mount said body in said aperture, said groove concentrically closely fitting said aperture when said body is so mounted; said wall being provided with surfaces bordering said aperture which operate when said body is inserted in said aperture to conform therewith, to bend said body toward said slit about a diametral axis disposed crosswise of said slit to bias said lips into face-to-face pressural contact with each other to cause said slit to be positively closed by said forces when an element separating said lips is removed from between these.
Claim 3
Dependent Claim
77 words
A combination as recited in claim 1 wherein shoulder means are provided on said rigid wall bordering said aperture, said means presenting a flat face forming a shallow dihedral angle to one of said peripheral flanges on said valve body so as to bend said valve body about a central transverse axis disposed crosswise to the plane of said slit to set up forces in said valve body biasing said lips into pressural contract with each other.
Claim 4
Dependent Claim
68 words
A combination as recited in claim 2 wherein two shoulder means, as aforesaid, are provided, one on the upper face of said wall and one on the lower face thereof, said two shoulder means forming approximately parallel dihedral angular faces and acting respectively on the upper and lower flanges of said valve body to bend said body about a transverse axis close to the apices of said angles.
Claim 5
Dependent Claim
34 words
A combination as recited in claim 2 wherein said shoulder means are annular in character thus extending entirely around said aperture, and the apex of said dihedral angle is diametrally related to said aperture.
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) | 1974-11-22 | 1975-05-24 | 1975-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-22 | 1979-05-24 | 1979-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-22 | 1983-05-24 | 1983-11-23 | $7700.00 | Window Closed / Lapsed |