US3798989A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple speed drive transmission
Assignee: Tokheim Corp
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Filing: 1972-07-10
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Granted: 1974-03-26
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Expires: 1992-07-10
Abstract
Abstract This invention relates to a transmission mechanism, for use for example on a bicycle, capable of varying the effective diameter of either the driver or driven member of the transmission, thereby altering the drive ratio involved. A manually settable ratio selecting mechanism actuates an interposer which forces radially outward a plurality of segments, thereby increasing the effective diameter, or releases the segments for retraction to a lesser effective diameter. A yieldable slack storing device maintains a fixed tension on a flexible drive means connecting the members of the transmission, thus compensating for the changing diameter of the transmission member.
Inventors
- 👤 G Hunt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:59
CPC Classifications
B; B62; B62M; B62M9/00; B62M9/04; B62M9/06; B62M9/08; F; F16; F16H; F16H55/00; F16H55/02; F16H55/30; F16H61/00; F16H61/66; F16H61/662
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
56 words
A transmission mechanism, comprising a. a variable diameter transmission member having a plurality of movable drive segments, and b. actuating means controlling said drive segments to vary the effective diameter of said transmission member by radially sliding said drive segments so as to be projected beyond the outer peripheral edge of said variable diameter transmission member.
Claim 2
Dependent Claim
56 words
A transmission mechanism, comprising a. a variable diameter transmission member having a plurality of movable drive segments, and b. actuating means controlling said drive segments to vary the effective diameter of said transmission member by radially sliding said drive segments so as to be projected beyond the outer peripheral edge of said variable diameter transmission member.
Claim 3
Dependent Claim
45 words
The structure as described in claim 1 wherein said actuating means comprises an interposer means capable of forcing radially outward said drive segments and allowing inward retraction of said drive segments, thereby operating to establish a plurality of predetermined effective diameters of said transmission member.
Claim 4
Dependent Claim
20 words
The structure as described in claim 2 wherein said actuating means further comprises remote control means actuating said interposer means.
Claim 5
Dependent Claim
30 words
The structure as described in claim 3 wherein said remote control means comprises a manual selector means and a Bowden cable to position said interposer means in its predetermined positions.
Claim 6
Dependent Claim
21 words
The structure as described in claim 3 wherein said interposer is spring biased to reposition in counter to remote control means.
Claim 7
Dependent Claim
34 words
The structure as described in claim 1 wherein said mechanism further includes a flexible drive means operatively connected to said transmission member, and wherein said transmission member constitutes a toothed sprocket for engagement therewith.
Claim 8
Dependent Claim
45 words
The structure as described in claim 6 wherein said mechanism further includes a yieldable chain accumulating means so as to accumulate or release slack in said flexible drive means in accordance with a decrease or increase, respectively in the effective diameter of said transmission member.
Claim 9
Dependent Claim
23 words
The structure as described in claim 1 wherein there is at least one pair of drive segments diametrically opposed on said transmission member.
Claim 10
Dependent Claim
28 words
The structure as described in claim 8 wherein said drive segments comprise a plurality of teeth on the outer periphery thereof for engagement with said flexible drive means.
Claim 11
Dependent Claim
36 words
The structure as described in claim 8 wherein said drive segments are physically positioned outwardly by said interposer operating through actuator arms pivoted by projecting actuator fingers, and held outwardly in detents in said drive segments.
Claim 12
Dependent Claim
30 words
The structure as described in claim 10 wherein said drive segments are spring biased inwardly for retraction to a lesser effective diameter, when said actuator arm release from said detents.
Claim 13
Dependent Claim
23 words
The structure as described in claim 1 wherein said transmission member further comprises a housing member non-rotatably fixed relative to a rotating shaft.
Claim 14
Dependent Claim
28 words
The structure as described in claim 12 wherein said drive segments and actuator arms are mounted within said housing for radial movement in response to said actuating means.
Claim 15
Dependent Claim
129 words
A bicycle comprising a frame, front and rear wheels mounted rotatably to said frame, a transmission system comprising a forward sprocket assembly mounted to the frame for rotation about a pedal crank axis and a rear sprocket assembly for driving said rear wheel, one of said forward sprocket assembly and said rear sprocket assembly having at least two sprocket segments capable of expanding radially, said sprocket segments having teeth on the periphery, thereof, a chain interconnecting said forward sprocket assembly and said rear sprocket assembly, an actuator mechanism consisting of a remote ratio selecting means, an interposer to force said sprocket segments raDially outward and release said sprocket segments for retraction, means operatively connecting said remote control means to said interposer, and a spring biased chain slack take-up mechanism.
Claim 16
Dependent Claim
129 words
A bicycle comprising a frame, front and rear wheels mounted rotatably to said frame, a transmission system comprising a forward sprocket assembly mounted to the frame for rotation about a pedal crank axis and a rear sprocket assembly for driving said rear wheel, one of said forward sprocket assembly and said rear sprocket assembly having at least two sprocket segments capable of expanding radially, said sprocket segments having teeth on the periphery, thereof, a chain interconnecting said forward sprocket assembly and said rear sprocket assembly, an actuator mechanism consisting of a remote ratio selecting means, an interposer to force said sprocket segments raDially outward and release said sprocket segments for retraction, means operatively connecting said remote control means to said interposer, and a spring biased chain slack take-up mechanism.
Claim 17
Dependent Claim
45 words
The structure as described in claim 14 wherein said remote ratio selecting means is mounted on said frame and comprising a selector member mounted for movement from one to another of a plurality of predetermined positions corresponding to an equal number of predetermined sprocket position.
Claim 18
Dependent Claim
27 words
The structure as described in claim 14 wherein said expandable sprocket assembly is mounted for rotation about an axis on said front drive sprocket of said bicycle.
Claim 19
Dependent Claim
27 words
The structure as described in claim 14 wherein said expandable sprocket assembly is mounted for rotation about an axis on said rear driven sprocket of said bicycle.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-25 | 1977-09-24 | 1978-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-25 | 1981-09-24 | 1982-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-25 | 1985-09-24 | 1986-03-26 | $7700.00 | Window Closed / Lapsed |