US3727478A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Speed controlled belt transmission
Assignee: First National Bank of Minneapolis
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Filing: 1971-08-23
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Granted: 1973-04-17
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Expires: 1991-08-23
Abstract
Abstract The disclosure is directed to an improved centrifugal clutch the structure of which permits its use with engines having different performance characteristics, and enables simple modification resulting in a desired performance relationship with the selected engine. One feature centers on a plurality of flyweights, each having an engageable cam surface that relates engine revolutionsper-minute to the input/output revolution ratio to effect a simulated gear shifting transmission characteristic. Other features are directed to laminated flyweights made of different materials to obtain the proper centrifugal action, and the mounting of flyweights having predetermined centers of mass to obtain the greatest mechanical advantage at the optimum time.
Inventors
- 👤 C Deschene
- 👤 A Erickson
- 👤 W Richards
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:07
CPC Classifications
F; F16; F16H; F16H55/00; F16H55/32; F16H55/52; F16H55/56; F16H55/563
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
279 words
A variable ratio centrifugal clutch driving assembly adapted for connection with a driven assembly by means of an endless belt, comprising: a. a rotatable shaft; b. a first rotatable member comprising a first sheave mounted on the shaft for rotation therewith and axially stationary thereon; c. a second rotatable member comprising a second sheave mounted on the shaft for rotation therewith and axially movable relative to the first sheave to variably control the radial position of an endless belt disposed therebetween; d. a third rotatable member mounted on the shaft for rotation therewith and axially stationary thereon; e. and a plurality of flyweights pivotally mounted on one of the second and third rotatable members and arranged to move radially outward with increasing rotational velocity of the shaft; f. each flyweight forming a cam surface characterized to effect a predetermined mode of movement of the second sheave with respect to the first sheave, said surface being engageable with cam engaging means disposed on the other of said second and third rotatable members to effect said mode of movement; g. and each flyweight having a predetermined center of mass and being supported so that said center of mass lies in an at rest position adjacent a line perpendicular to the shaft axis and extending through the pivotal support to maintain the moment arm through which the flyweight acts essentially ineffective below a predetermined rotational velocity of the shaft means and substantially preclude axial movement of said second rotatable member until said predetermined rotational velocity of the shaft has been attained, the distance between the center of mass and said line increasing as a direct function of rotational velocity of the shaft.
Claim 2
Dependent Claim
279 words
A variable ratio centrifugal clutch driving assembly adapted for connection with a driven assembly by means of an endless belt, comprising: a. a rotatable shaft; b. a first rotatable member comprising a first sheave mounted on the shaft for rotation therewith and axially stationary thereon; c. a second rotatable member comprising a second sheave mounted on the shaft for rotation therewith and axially movable relative to the first sheave to variably control the radial position of an endless belt disposed therebetween; d. a third rotatable member mounted on the shaft for rotation therewith and axially stationary thereon; e. and a plurality of flyweights pivotally mounted on one of the second and third rotatable members and arranged to move radially outward with increasing rotational velocity of the shaft; f. each flyweight forming a cam surface characterized to effect a predetermined mode of movement of the second sheave with respect to the first sheave, said surface being engageable with cam engaging means disposed on the other of said second and third rotatable members to effect said mode of movement; g. and each flyweight having a predetermined center of mass and being supported so that said center of mass lies in an at rest position adjacent a line perpendicular to the shaft axis and extending through the pivotal support to maintain the moment arm through which the flyweight acts essentially ineffective below a predetermined rotational velocity of the shaft means and substantially preclude axial movement of said second rotatable member until said predetermined rotational velocity of the shaft has been attained, the distance between the center of mass and said line increasing as a direct function of rotational velocity of the shaft.
Claim 3
Dependent Claim
17 words
The centrifugal clutch defined by claim 1, wherein the flyweights are mounted on the third rotatable member.
Claim 4
Dependent Claim
36 words
The centrifugal clutch defined by claim 1, wherein the third rotatable member comprises a hub with a plurality of arm extending rAdially outward therefrom, and a flyweight is mounted on the outer end of each arm.
Claim 5
Dependent Claim
26 words
The centrifugal clutch defined by claim 3, wherein a low friction roller for each flyweight is mounted on the second rotatable member for rolling engagement therewith.
Claim 6
Dependent Claim
18 words
The centrifugal clutch defined by claim 1, wherein the flyweights are formed from a plurality of constituent parts.
Claim 7
Dependent Claim
19 words
The centrifugal clutch defined by claim 5, wherein at least two of the constituent parts are of different material.
Claim 8
Dependent Claim
17 words
The centrifugal clutch defined by claim 5, wherein the constituent parts are removably connected to permit interchangeability.
Claim 9
Dependent Claim
27 words
The centrifugal clutch defined by claim 1, wherein each flyweight comprises a plurality of weight members of essentially the same shape joined to form a laminate structure.
Claim 10
Dependent Claim
50 words
The centrifugal clutch defined by claim 1, wherein each flyweight cam surface includes a recessed portion disposed to resist said radially outward movement and thereby maintain said first and second rotatable members in a predetermined relative axial position in accordance with a predetermined range of rotational speed of the shaft.
Claim 11
Dependent Claim
29 words
The centrifugal clutch defined by claim 9, wherein the recessed portion of the cam surface is disposed to engage said other rotatable member as the shaft begins to rotate.
Claim 12
Dependent Claim
29 words
The centrifugal clutch defined by claim 9, wherein the cam surface recess portion is disposed to engage said other rotatable member through an intermediate range of shaft rotational speed.
Claim 13
Dependent Claim
208 words
A centrifugal clutch adapted for use with an endless belt, comprising: a. rotatable shaft means; b. a first rotatable member mounted on the shaft means and defining a first sheave, the first rotatable member being axially stationary on the shaft means; c. a second rotatable member mounted on the shaft means and defining a second sheave, the second rotatable member being axially movable on the shaft means to effect relative axial movement between the first and second sheaves and thereby vary the effective diameter therebetween; d. a third rotatable member mounted on the shaft means and axially stationary thereon; e. and a plurality of flyweights pivotally mounted on one of said second and third rotatable members and arranged to move radially outward with increasing rotational velocity of the shaft means, each of the flyweights having a cam surface engageable with the other of said second and third rotatable members upon said radially outward movement to effect said axial movement of the second rotatable member, the cam surface including a recessed portion disposed at an intermediate point thereon to resist said radially outward movement and thereby maintain said first and second members in a predetermined relative axial position through an intermediate range of rotational speed of the shaft means.
Claim 14
Dependent Claim
208 words
A centrifugal clutch adapted for use with an endless belt, comprising: a. rotatable shaft means; b. a first rotatable member mounted on the shaft means and defining a first sheave, the first rotatable member being axially stationary on the shaft means; c. a second rotatable member mounted on the shaft means and defining a second sheave, the second rotatable member being axially movable on the shaft means to effect relative axial movement between the first and second sheaves and thereby vary the effective diameter therebetween; d. a third rotatable member mounted on the shaft means and axially stationary thereon; e. and a plurality of flyweights pivotally mounted on one of said second and third rotatable members and arranged to move radially outward with increasing rotational velocity of the shaft means, each of the flyweights having a cam surface engageable with the other of said second and third rotatable members upon said radially outward movement to effect said axial movement of the second rotatable member, the cam surface including a recessed portion disposed at an intermediate point thereon to resist said radially outward movement and thereby maintain said first and second members in a predetermined relative axial position through an intermediate range of rotational speed of the shaft means.
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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) | 1976-04-16 | 1976-10-16 | 1977-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-16 | 1980-10-16 | 1981-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-16 | 1984-10-16 | 1985-04-17 | $7700.00 | Window Closed / Lapsed |