Patent US3918838A successfully refreshed from Google Patents.
US3918838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Metal reinforced plastic helical screw compressor rotor
Assignee: MARSHALL INDUSTRIES Inc
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Filing: 1974-01-04
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Granted: 1975-11-11
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Expires: 1994-01-04
Abstract
Abstract Metal plates whose periphery is configured generally to that of a finished helical screw compressor rotor are fixedly stacked on a rotor shaft at axially spaced positions to form a metal skeleton of a finished rotor, and a unitary rotor is completed by molding a plastic jacket between the plates around the shaft and about the periphery thereof.
Inventors
- 👤 Jr Harold W Moody
- 👤 Clifford T Bulkley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:16
CPC Classifications
F; F04; F04C; F04C18/00; F04C18/08; F04C18/082; F04C18/084; B; B29; B29C; B29C45/00; B29C45/14
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
96 words
A helical screw compressor rotor comprising: a central shaft, a plurality of metal plates fixedly stacked on said rotor shaft in concentric fashion at axially spaced positions to form a metal skeleton, said plates having an outer periphery configured generally to that of the finished helical screw compressor rotor profile and comprising helical lobes of given pitch, forming helical grooves therebetween, and a plastic jacket encapsulating said metal skeleton, and filling the spaces between said plates to rigidly connect said spaced plates together and form a unitary, light weight, solid rotor of high load bearing capability.
Claim 2
Dependent Claim
96 words
A helical screw compressor rotor comprising: a central shaft, a plurality of metal plates fixedly stacked on said rotor shaft in concentric fashion at axially spaced positions to form a metal skeleton, said plates having an outer periphery configured generally to that of the finished helical screw compressor rotor profile and comprising helical lobes of given pitch, forming helical grooves therebetween, and a plastic jacket encapsulating said metal skeleton, and filling the spaces between said plates to rigidly connect said spaced plates together and form a unitary, light weight, solid rotor of high load bearing capability.
Claim 3
Dependent Claim
87 words
The helical screw compressor rotor as claimed in claim 1 wherein said plates have an outer periphery consisting of radially projecting lobes at spaced circumferential positions, a central opening corresponding to the diameter of the shaft carrying the same, said shaft includes a helical keyway within the periphery of the same and said plates are provided with radial tabs within said openings of similar size and configuration to and positioned within said keyway such that said plates are skewed in the manner defined by the helical keyway.
Claim 4
Dependent Claim
45 words
The helical screw compressor rotor as claimed in claim 1 further comprising spacer rings having an inner diameter on the order of the shaft, and being stacked on said shaft between said plates in alternating fashion with said plates for uniformly spacing said plates axially.
Claim 5
Dependent Claim
46 words
The helical screw compressor rotor as claimed in claim 2 further comprising spacer rings positioned having an inner diameter on the order of the shaft, and being stacked on said shaft between said plates in alternating fashion with said plates for uniformly spacing said plates axially.
Claim 6
Dependent Claim
47 words
The helical screw compressor rotor as claimed in claim 1 wherein the lobes of said plates carry at least one opening therein, and wherein said encapsulated plastic fills said openings to form helical reinforcing bars extending through said rotor from end to end at each lobe location.
Claim 7
Dependent Claim
47 words
The helical screw compressor rotor as claimed in claim 2 wherein the lobes of said plates carry at least one opening therein, and wherein said encapsulated plastic fills said openings to form helical reinforcing bars extending through said rotor from end to end at each lobe location.
Claim 8
Dependent Claim
48 words
The helical screw compressor rotor as claimed in claim 3 wherein the lobes of said plates carry at least one opening therein, and wherein said encapsulated of plastic fills said openings to form helical reinforcing bars extending through said rotor from end to end at each lobe location.
Claim 9
Dependent Claim
47 words
The helical screw compressor rotor as claimed in claim 4 wherein the lobes of said plates carry at least one opening thErein, and wherein said encapsulated plastic fills said openings to form helical reinforcing bars extending through said rotor from end to end at each lobe location.
Claim 10
Dependent Claim
26 words
The helical screw compressor rotor as claimed in claim 5 wherein said openings are elongated radially and extend over a substantial radial extent of said lobes.
Claim 11
Dependent Claim
26 words
The helical screw compressor rotor as claimed in claim 6 wherein said openings are elongated radially and extend over a substantial radial extent of said lobes.
Claim 12
Dependent Claim
26 words
The helical screw compressor rotor as claimed in claim 7 wherein said openings are elongated radially and extend over a substantial radial extent of said lobes.
Claim 13
Dependent Claim
26 words
The helical screw compressor rotor as claimed in claim 8 wherein said openings are elongated radially and extend over a substantial radial extent of said lobes.
Claim 14
Dependent Claim
36 words
The helical screw compressor as claimed in claim 1, wherein hardened metal strips extend longitudinally along at least one of the flanks of the plate lobes with one surface thereof lying flush with said plastic jacket.
Claim 15
Dependent Claim
36 words
The helical screw compressor as claimed in claim 2, wherein hardened metal strips extend longitudinally along at least one of the flanks of the plate lobes with one surface thereof lying flush with said plastic jacket.
Claim 16
Dependent Claim
36 words
The helical screw compressor as claimed in claim 3, wherein hardened metal strips extend longitudinally along at least one of the flanks of the plate lobes with one surface thereof lying flush with said plastic jacket.
Claim 17
Dependent Claim
36 words
The helical screw compressor as claimed in claim 3, wherein hardened metal strips extend longitudinally along at least one of the flanks of the plate lobes with one surface thereof lying flush with said plastic jacket.
Claim 18
Dependent Claim
36 words
The helical screw compressor as claimed in claim 13, wherein: said lobes of said metal plates have notches formed within their flanks at each metal strip location and said strips are fixedly received within said notches.
Claim 19
Dependent Claim
36 words
The helical screw compressor as claimed in claim 16, wherein: said lobes of said metal plates have notches formed within their flanks at each metal strip location and said strips are fixedly received within said notches.
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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) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |