US3580419A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for feeding and compacting finely divided particulate material
Assignee: Carter Engineering Co
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Filing: 1968-04-02
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Granted: 1971-05-25
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Expires: 1988-04-02
Abstract
Abstract A method of feeding and compacting finely divided particulate material, which utilizes a rotating screw feeder for advancing the material along a sleeve passage provided by a stationary foraminous sleeve mounted closely about the screw feeder. The method includes the steps of advancing the particulate material axially along the sleeve with the interstitial air between the particles in the sleeve at an internal sleeve pressure. Suction pressure relatively lower than the internal sleeve pressure is applied to the exterior of the sleeve to withdraw air from between the particles of the material to effect compaction of the material. At predetermined times gas pressure relatively higher than the internal sleeve pressure is applied to the exterior of the sleeve to back-flush material from openings in the sleeve to prevent clogging thereof. An apparatus for feeding and compacting finely divided particulate material, which includes a housing having fixedly mounted therein a tubular sleeve. The sleeve and housing define at least one closed hollow chamber extending about the sleeve with a plurality of perforations in the sleeve placing the interior thereof in fluid communication with the interior of the chamber. An axially extending screw feeder concentrically and rotatably mounted in the sleeve is adapted to advance material axially along the sleeve, with the interstitial air present between the particles of material in the sleeve at an internal sleeve pressure. Suction means in fluid communication with the chamber applies suction pressure relatively lower than the internal sleeve pressure to withdraw air from between the particles of material to affect compaction thereof. Gas pressure means in fluid communication with the chamber provides gas at a relatively higher pressure than the internal sleeve pressure at predetermined times to backflush particulate material from the perforations, to prevent clogging thereof.
Inventors
- 👤 Clarence F Carter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:44
CPC Classifications
B; B65; B65G; B65G69/00; B65G69/20; B65B; B65B63/00; B65B63/02; B65B63/028
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
221 words
A method of continuously feeding and compacting finely divided particulate material utilizing a rotating screw feeder for advancing the material through a sleeve passage provided by a stationary foraminous sleeve mounted closely about the screw feeder, the method comprising the steps of: mechanically advancing the particulate material along the sleeve passage with the interstitial air between particles of the material in the sleeve being at an internal sleeve pressure, applying, from a suction pressure system, a suction pressure relatively lower than the internal sleeve pressure along the exterior of the sleeve to withdraw at least a portion of the interstitial air from between the particles of the material through the sleeve to effect compaction of the material, providing noncommunicating closed hollow chambers axially extending the length of the sleeve about different peripherally spaced areas of the sleeve; applying, while continuing to mechanically advance the material, a gas pressure relatively higher than the internal sleeve pressure along the lateral surface of each of the chambers in turn at predetermined times during which the other of the chambers has suction pressure applied thereto to cause a pressure differential across the perforations to back-flush particulate material from the perforations in the sleeve to prevent clogging thereof; and simultaneously preventing gas pressure from entering the end of the sleeve passage and the suction pressure system.
Claim 2
Independent Claim
221 words
A method of continuously feeding and compacting finely divided particulate material utilizing a rotating screw feeder for advancing the material through a sleeve passage provided by a stationary foraminous sleeve mounted closely about the screw feeder, the method comprising the steps of: mechanically advancing the particulate material along the sleeve passage with the interstitial air between particles of the material in the sleeve being at an internal sleeve pressure, applying, from a suction pressure system, a suction pressure relatively lower than the internal sleeve pressure along the exterior of the sleeve to withdraw at least a portion of the interstitial air from between the particles of the material through the sleeve to effect compaction of the material, providing noncommunicating closed hollow chambers axially extending the length of the sleeve about different peripherally spaced areas of the sleeve; applying, while continuing to mechanically advance the material, a gas pressure relatively higher than the internal sleeve pressure along the lateral surface of each of the chambers in turn at predetermined times during which the other of the chambers has suction pressure applied thereto to cause a pressure differential across the perforations to back-flush particulate material from the perforations in the sleeve to prevent clogging thereof; and simultaneously preventing gas pressure from entering the end of the sleeve passage and the suction pressure system.
Claim 3
Dependent Claim
116 words
A method of feeding and compacting finely divided particulate material as defined in claim 1 and further comprising the steps of: utilizing an axially advancing screw blade having an axially extending lip flush with the interior surface of the sleeve scraping the adhered material from the interior surface all along the sleeve, simultaneously spirally blanking off portions of the interior of the sleeve from the vacuum in the area embraced by the axially extending blade lip to diminish the suction forces causing the particulate material to adhere to the interior of the sleeve during scraping thereof, and opening the interior of the sleeve to vacuum in the area following the area embraced by the advancing blade.
Claim 4
Independent Claim
291 words
An apparatus for feeding and compacting finely divided particulate material having interstitial air between the particles, the apparatus comprising: a housing, a tubular sleeve fixedly mounted in said housing, said sleeve and adjacent interior portions of said housing defining, at least one closed hollow chamber extending about said sleeve; said sleeve further including, a plurality of perforations placing said chamber in fluid communication with the interior of said sleeve; an axially extending screw feeder concentrically and rotatably mounted in said sleeve, said feeder upon rotation thereof adapted to feed the particulate material axially along said sleeve with the interstitial air being at an internal sleeve pressure; partition means within said chamber extending between and fixedly secured to said housing and sleeve, said partition means dividing said chamber into at least two axially extending, noncommunicating subchambers extending peripherally about different portions of said s sleeve; suction means connected with said housing for selectively applying suction pressure relatively lower than the internal sleeve pressure through said perforations to the interior of said sleeve to withdraw along the lateral surface of the sleeve at least a portion of the interstitial air from the particulate material to effect compaction thereof during feeding including first suction means communicating only with one of said subchambers and, second suction means communicating only with the other of said subchambers; gas pressure means connected with said housing for supplying gas at a relatively higher pressure than the internal sleeve pressure to said perforations along the lateral surface of said sleeve at predetermined times to back-flush particulate material from said perforations to prevent clogging thereof, including first gas pressure means communicating only with said one of said subchambers; and second gas pressure means communicating only with said other of said subchambers.
Claim 5
Independent Claim
291 words
An apparatus for feeding and compacting finely divided particulate material having interstitial air between the particles, the apparatus comprising: a housing, a tubular sleeve fixedly mounted in said housing, said sleeve and adjacent interior portions of said housing defining, at least one closed hollow chamber extending about said sleeve; said sleeve further including, a plurality of perforations placing said chamber in fluid communication with the interior of said sleeve; an axially extending screw feeder concentrically and rotatably mounted in said sleeve, said feeder upon rotation thereof adapted to feed the particulate material axially along said sleeve with the interstitial air being at an internal sleeve pressure; partition means within said chamber extending between and fixedly secured to said housing and sleeve, said partition means dividing said chamber into at least two axially extending, noncommunicating subchambers extending peripherally about different portions of said s sleeve; suction means connected with said housing for selectively applying suction pressure relatively lower than the internal sleeve pressure through said perforations to the interior of said sleeve to withdraw along the lateral surface of the sleeve at least a portion of the interstitial air from the particulate material to effect compaction thereof during feeding including first suction means communicating only with one of said subchambers and, second suction means communicating only with the other of said subchambers; gas pressure means connected with said housing for supplying gas at a relatively higher pressure than the internal sleeve pressure to said perforations along the lateral surface of said sleeve at predetermined times to back-flush particulate material from said perforations to prevent clogging thereof, including first gas pressure means communicating only with said one of said subchambers; and second gas pressure means communicating only with said other of said subchambers.
Claim 6
Dependent Claim
85 words
An apparatus as defined in claim 3 wherein said screw feeder includes, an axially extending shaft concentrically positioned within and spaced from said sleeve, an axially extending screw flight secured to said shaft extending generally helically therealong, said flight including, a peripheral edge closely adjacent interior portions of said sleeve, a lip fixedly secured to said screw flight extending continuously along said peripheral edge, said lip extending axially downstream from said edge and said lip being in contact with adjacent interior portions of said sleeve.
Claim 7
Dependent Claim
53 words
An apparatus as defined in claim 3 further including, a tubular sleeve check valve connected with said sleeve adjacent an outlet end of said passage for restrictively permitting outward passage of particulate material through the sleeve to maintain a back pressure on the material and preventing ingress of air into said outlet passage.
Claim 8
Dependent Claim
162 words
An apparatus as defined in claim 3 further including, first and second suction valves connected with said first and second means respectively, each of said suction valves upon opening thereof placing the associated one of said first and second suction means in fluid communication with the associated one of said subchambers; and first and second gas valves connected with said first and second gas pressure means respectively, each of said gas valves upon opening thereof placing the associated one of said first and second gas pressure means in fluid communication with the associated one of said subchambers, said first gas valve being opened concurrently with closing of said first suction valve at predetermined times during which said second gas valve is closed and said second suction valve is open, said second gas valve being opened concurrently with closing of said second suction valve at other predetermined times during which said first gas valve is closed and said first suction valve is open.
Claim 9
Dependent Claim
41 words
An apparatus as defined in claim 3 further including, a laYer of perforate mesh of smaller mesh size than the size of the particles, said layer of mesh contiguously overlying said sleeve on a surface hereof facing inwardly of said chamber.
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) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |