US4370899A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flywheel for kinetic energy storage
Assignee: U S FLYWHEELS Inc
•
Filing: 1980-07-21
•
Granted: 1983-02-01
•
Expires: 2000-07-21
Abstract
Abstract A unitary, wide rim of fiber composite material for use in conjunction with flywheels for inertial energy storage apparatus, the rim being fabricated to minimize radial stresses and equalize hoop stresses ordinarily produced at high speed rotation of the flywheel. Novel fabrication techniques include varying the density of the rim as a function of radius by means of ballasting; and using a combination of layers of fibers having different modulus of elasticity. By utilizing the aforesaid novel fabrication techniques, a preferred embodiment of a unitary, thick flywheel rim achieves radial stress reduction to trivial levels and hoop stress equalization sufficient to permit extremely efficient energy storage as a function of flywheel weight.
Inventors
- 👤 Bruce E. Swartout
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 01:47
CPC Classifications
F; F16; F16F; F16F15/00; F16F15/30; F16F15/305; Y; Y02; Y02E; Y02E60/00; Y02E60/16; Y10; Y10T; Y10T74/00; Y10T74/21; Y10T74/2117; Y10T74/2119; Y10T74/212
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
177 words
A flywheel for storing kinetic energy and comprising: a double spider configuration hub having a pair of coaxial, oppositely facing, spaced-apart convex surfaces of substantially equal dimensions, said surfaces being interconnected by a plurality of legs spaced equidistantly around the perimeter of said hub; and each of said legs having a circumferential outward facing surface for support of a cylindrical flywheel rim, the axis of which is collinear with the axes of said convex surfaces; a unitary, thick rim, concentrically supported on said leg surfaces and having a first combination on fiber and epoxy matrix wound onto a substantially cylindrical configuration having an inner radius R1 and an outer radius R2 and a second combination of fiber and epoxy matrix wound into a substantially cylindrical configuration having an inner radius R2 and an outer radius R3; the mass density per unit volume of said first combination being greater than the mass density per unit volume of said second combination; and the elastic modulus of said second combination being greater than the elastic modulus of said first combination.
Claim 2
Dependent Claim
177 words
A flywheel for storing kinetic energy and comprising: a double spider configuration hub having a pair of coaxial, oppositely facing, spaced-apart convex surfaces of substantially equal dimensions, said surfaces being interconnected by a plurality of legs spaced equidistantly around the perimeter of said hub; and each of said legs having a circumferential outward facing surface for support of a cylindrical flywheel rim, the axis of which is collinear with the axes of said convex surfaces; a unitary, thick rim, concentrically supported on said leg surfaces and having a first combination on fiber and epoxy matrix wound onto a substantially cylindrical configuration having an inner radius R1 and an outer radius R2 and a second combination of fiber and epoxy matrix wound into a substantially cylindrical configuration having an inner radius R2 and an outer radius R3; the mass density per unit volume of said first combination being greater than the mass density per unit volume of said second combination; and the elastic modulus of said second combination being greater than the elastic modulus of said first combination.
Claim 3
Dependent Claim
25 words
A flywheel as defined in claim 1, wherein the fiber of said first combination is E-Glass and the fiber of said second combination is Kevlar.
Claim 4
Dependent Claim
54 words
A flywheel as defined in claim 1, in which the mass density per unit volume of said first combination varies as a function of rim radius by means of ballasting said first combination with a pre-selected quantity of substantially higher density material, said quantity being greatest at R1 and decreasing with increasing rim radius.
References Cited (Backward Citations)
US857303A
Cited
US3363479A
Cited
US3318165A
Cited
US3296886A
Cited
US3602066A
Cited
US3602067A
Cited
US3788162A
Cited
US3964341A
Cited
US4036080A
Cited
US4000665A
Cited
US4020714A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-31 | 1986-08-02 | 1987-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-31 | 1990-08-02 | 1991-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-31 | 1994-08-02 | 1995-02-01 | $7700.00 | Window Closed / Lapsed |