US3798841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure feed for sand blast abrasive
Assignee: Individual
•
Filing: 1972-06-13
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Granted: 1974-03-26
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Expires: 1992-06-13
Abstract
Abstract A check valve yields under weight of abrasive in a hopper to deliver abrasive into a pressure chamber from which it is fed by rotating feeder arms into metering orifices in a plate adjustable in the bottom of the chamber. A resilient valve retractable at an angle from the path of the grit permits the grit to issue through a selected metering orifice as needed for delivery into a convection air current en route to a blast gun or guns.
Inventors
- 👤 A Eppler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:53
CPC Classifications
B; B24; B24C; B24C7/00; B24C7/0046; B24C7/0053
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
86 words
In a sand blast device the combination with a feed chamber for supplying abrasive grit and having a bottom wIth a metering aperture, of means for maintaining grit in said chamber under pressure, means for providing a valved duct leading from said aperture, and a pressure line for convection air to receive grit from said duct and with which said duct communicates, a feed arm being mounted in said chamber has means for actuating it across said aperture for assuring delivery of grit to said duct.
Claim 2
Dependent Claim
86 words
In a sand blast device the combination with a feed chamber for supplying abrasive grit and having a bottom wIth a metering aperture, of means for maintaining grit in said chamber under pressure, means for providing a valved duct leading from said aperture, and a pressure line for convection air to receive grit from said duct and with which said duct communicates, a feed arm being mounted in said chamber has means for actuating it across said aperture for assuring delivery of grit to said duct.
Claim 3
Dependent Claim
36 words
A sand blast device according to claim 1 in which said bottom comprises at least a part which is adjustable and provided with a plurality of such apertures of differing diameters selectively registrable with said duct.
Claim 4
Dependent Claim
19 words
A sand blast device according to claim 2 in which said part is a disk rotatable in the chamber.
Claim 5
Dependent Claim
24 words
A device according to claim 1 in which said bottom comprises an insert selectively interchangeable to provide a metering orifice of selected cross section.
Claim 6
Dependent Claim
28 words
A sand blast device according to claim 1 in which said arm is mounted on a shaft having seal protected bearing means and spaced slightly from said bottom.
Claim 7
Dependent Claim
98 words
In a sand blast device the combination with a feed chamber for supplying abrasive grit and having a bottom with a metering aperture, of means for maintaining grit in said chamber under pressure, means for providing a valved duct leading from said aperture, and a pressure line for convection air to receive said grit from said duct and with which said duct communicates, said duct being provided with an annular seat having an axis at an acute angle to said duct, and a valve having means mounting it for movement to and from said seat along said axis.
Claim 8
Dependent Claim
98 words
In a sand blast device the combination with a feed chamber for supplying abrasive grit and having a bottom with a metering aperture, of means for maintaining grit in said chamber under pressure, means for providing a valved duct leading from said aperture, and a pressure line for convection air to receive said grit from said duct and with which said duct communicates, said duct being provided with an annular seat having an axis at an acute angle to said duct, and a valve having means mounting it for movement to and from said seat along said axis.
Claim 9
Dependent Claim
51 words
A sand blast device according to claim 6 in which said line has a diaphragm substantially normal to said axis and constituting part of said mounting means, the valve having a stem on said axis and connected with said diaphragm, and valve seating means sealed from said line by said diaphragm.
Claim 10
Dependent Claim
41 words
A sand blast device according to claim 6 in which said seat is concave and said valve is complementarily convex, the angle of said axis being such that said duct is substantially unobstructed when said valve is retracted from said seat.
Claim 11
Dependent Claim
34 words
A sand blast device according to claim 7 in which a housing is part of said line and has said diaphragm for one wall, the said line joining said duct at an acute angle.
Claim 12
Dependent Claim
20 words
A sand blast device according to claim 7 in which the valve is bulbous and consists of a rubber material.
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) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |