Patent US3869932A successfully refreshed from Google Patents.
US3869932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spring biased double acting expansible pulley with increased spring fatigue life
Assignee: SPEED SELECTOR Inc
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Filing: 1973-05-23
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Granted: 1975-03-11
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Expires: 1993-05-23
Abstract
Abstract A variable drive pulley includes first and second pulley parts, at least one of which is shiftable toward and away from the other. A leaf spring assembly normally biases the one pulley part toward the other pulley part. The leaf springs have flat mounting end portions secured between a flat circular inner plate and a larger outer plate. The leaf springs extend parallel to the facing surfaces of the plates and then just beyond the outer edge of the smaller plate smoothly diverge away from the larger outer plate with a curved tangent to the surface thereof. During flexure of the springs, the curved portions roll along the inner surface of the outer plate so that flexure occurs over a length of spring as opposed to at a precise point or edge.
Inventors
- 👤 Peter C Fletcher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 19:06
CPC Classifications
F; F16; F16H; F16H55/00; F16H55/32; F16H55/52; F16H55/56
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
134 words
In a variable pitch pulley having a pair of pulley halves relatively axially movable and resilient means for biasing said halves toward each other including a mounting member having an outermost edge and a surface facing axially toward one of said pully halves; and a plurality of radially extending leaf springs having an inner most mounting portion mounted against surface and an outer most portion bearing against one of said pulley halves and an intermediate flexing portion, the improvement which comprises: said axially facing surface extending radially outwardly beyond said outermost edge and said flexing portion diverging from said surface from a place radially inwardly of said outermost portion in a smooth tangent curve whereby the radially outermost place of engagement of said flexing portion with said surface moves radially outwardly as flexure occurs.
Claim 2
Dependent Claim
134 words
In a variable pitch pulley having a pair of pulley halves relatively axially movable and resilient means for biasing said halves toward each other including a mounting member having an outermost edge and a surface facing axially toward one of said pully halves; and a plurality of radially extending leaf springs having an inner most mounting portion mounted against surface and an outer most portion bearing against one of said pulley halves and an intermediate flexing portion, the improvement which comprises: said axially facing surface extending radially outwardly beyond said outermost edge and said flexing portion diverging from said surface from a place radially inwardly of said outermost portion in a smooth tangent curve whereby the radially outermost place of engagement of said flexing portion with said surface moves radially outwardly as flexure occurs.
Claim 3
Dependent Claim
134 words
In a variable pitch pulley having a pair of pulley halves relatively axially movable and resilient means for biasing said halves toward each other including a mounting member having an outermost edge and a surface facing axially toward one of said pully halves; and a plurality of radially extending leaf springs having an inner most mounting portion mounted against surface and an outer most portion bearing against one of said pulley halves and an intermediate flexing portion, the improvement which comprises: said axially facing surface extending radially outwardly beyond said outermost edge and said flexing portion diverging from said surface from a place radially inwardly of said outermost portion in a smooth tangent curve whereby the radially outermost place of engagement of said flexing portion with said surface moves radially outwardly as flexure occurs.
Claim 4
Dependent Claim
134 words
In a variable pitch pulley having a pair of pulley halves relatively axially movable and resilient means for biasing said halves toward each other including a mounting member having an outermost edge and a surface facing axially toward one of said pully halves; and a plurality of radially extending leaf springs having an inner most mounting portion mounted against surface and an outer most portion bearing against one of said pulley halves and an intermediate flexing portion, the improvement which comprises: said axially facing surface extending radially outwardly beyond said outermost edge and said flexing portion diverging from said surface from a place radially inwardly of said outermost portion in a smooth tangent curve whereby the radially outermost place of engagement of said flexing portion with said surface moves radially outwardly as flexure occurs.
Claim 5
Dependent Claim
32 words
The improvement of claim 1 wherein said mounting portions have radially extending side edges and said edges of adjacent mounting portions generally abutt whereby said springs are held in radially extending relationship.
Claim 6
Dependent Claim
18 words
The improvement of claim 2 wherein each flexing portion has edges outwardly of said mounting portion which converge.
Claim 7
Dependent Claim
39 words
The improvement of claim 1 including a second mounting member abutting against the sides of said mounting portions remote from said first mounting member and having an outer peripheral edge radially inwardly of outermost edges of said mounting member.
Claim 8
Dependent Claim
17 words
The improvement of claim 1 wherein each leaf spring is comprised of a plurality of thin laminations.
Claim 9
Dependent Claim
18 words
The improvement of claim 5 wherein the laminations axially further away from said pulley half are radially shorter.
Claim 10
Dependent Claim
15 words
The improvement of claim 1 wherein said surface is flat and said spring is curved.
References Cited (Backward Citations)
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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) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |