US4993539A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Screw feeding devices
Assignee: Stockrail International Ltd
•
Filing: 1989-09-18
•
Granted: 1991-02-19
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Expires: 2009-09-18
Abstract
Abstract The invention provides a length of feed screw for connection between two straight lengths of screw conveyor, the length of feed screw being of a material which can be flexed, but being slotted to facilitate bending of the length of feed screw so that the length of feed screw can continue to operate in the bent condition.
Inventors
- 👤 Edward C. Duce
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:26
CPC Classifications
B; B65; B65G; B65G33/00; B65G33/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
89 words
A feed screw device for transporting articles, said device comprising: (a) a hollow rod of a rigid plastic material, said rod including an outer periphery; (b) a raised helical land along the outer periphery of the hollow rod; (c) a helical groove which is defined between the land and from which articles may be suspended; and (d) a continuous helical slot which opens into the bore of the rod and imparts to said rod a degree of resilience sufficient for it to form a curve of a required shape.
Claim 2
Dependent Claim
89 words
A feed screw device for transporting articles, said device comprising: (a) a hollow rod of a rigid plastic material, said rod including an outer periphery; (b) a raised helical land along the outer periphery of the hollow rod; (c) a helical groove which is defined between the land and from which articles may be suspended; and (d) a continuous helical slot which opens into the bore of the rod and imparts to said rod a degree of resilience sufficient for it to form a curve of a required shape.
Claim 3
Dependent Claim
32 words
A resilient feed screw according to claim 1 connected at least at one end to a length of straight feed screw such that suspended articles can be transferred between said feed screws.
Claim 4
Dependent Claim
15 words
A feed screw according to claim 1, wherein the continuous slot passes through said lands.
Claim 5
Dependent Claim
21 words
A feed screw according to claim 1, wherein the continuous slot is formed in the rod at positions between the land.
Claim 6
Dependent Claim
17 words
A feed screw according to any preceding claim, wherein the feed screw includes a bendable core shaft.
Claim 7
Dependent Claim
35 words
A feed screw according to claim 2, wherein two straight feed screw sections are connected to respective ends of the resilient feed screw, said straight feed screw sections lying at an angle to each other.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-18 | 1994-08-20 | 1995-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-18 | 1998-08-20 | 1999-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-18 | 2002-08-20 | 2003-02-19 | $7700.00 | Window Closed / Lapsed |