US3929025A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic shift control for bicycles and the like
Assignee: Individual
•
Filing: 1974-12-13
•
Granted: 1975-12-30
•
Expires: 1994-12-13
Abstract
Abstract An automatic shift control for a vehicle, such as a bicycle, of the type including a frame, at least one wheel, a crank, a chain interconnecting the wheel and the crank, and means for changing the rotation ratio between the wheel and the crank. The automatic shift control operates the ratio changing means by sensing changes in chain tension which result from variations in pedal pressure used to propel the bicycle and includes a control arm mounted for rotation around a fixed point on the frame, the arm being positionable in any one of multiple positions; means interconnecting the control arm and the ratio changing means for selecting one of multiple ratios depending upon the position of the control arm; a chain-engaging idler wheel mounted on the control arm, chain tension tending to cause rotation of the control arm in one direction; and a tension spring connected to the control arm for applying a force thereto tending to cause rotation thereof in an opposite direction. The control arm is in equilibrium for a selected chain tension in all of the multiple positions of the control arm and only a difference between actual chain tension and the selected chain tension causes rotation of the control arm in a direction to eliminate such difference. The control arm senses the above difference at a point in the pedaling cycle where the selected chain tension is consistent and the control arm is limited to moving one position for each rotation of the pedals.
Inventors
- 👤 Robert E Perry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:27
CPC Classifications
B; B62; B62M; B62M9/00; B62M9/16; B62M9/04; B62M9/06; B62M9/10; B62M9/12; B62M9/121; B62M9/123
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
184 words
An automatic shift control for a vehicle including a frame, at least one wheel, a crank, a chain interconnecting said wheel and said crank, and a means for changing the rotation ratio between said wheel and said crank comprising: a control arm mounted for rotation around a fixed point on said frame, said arm being positionable in any one of multiple positions; means interconnecting said control arm and said ratio changing means for selecting one of multiple ratios depending upon the position of said control arm; a control arm idler wheel mounted on said control arm, said chain extending over said control arm idler wheel and forming an acute angle relative thereto, the resultant chain-tension force being in a direction to cause rotation of said control arm in a first direction; and tension means connected to said control arm for applying a force in a direction to cause rotation of said control arm in a second direction opposite to said first direction, said control arm being approximately in equilibrium for a selected chain tension in all of said multiple positions of said control arm.
Claim 2
Dependent Claim
184 words
An automatic shift control for a vehicle including a frame, at least one wheel, a crank, a chain interconnecting said wheel and said crank, and a means for changing the rotation ratio between said wheel and said crank comprising: a control arm mounted for rotation around a fixed point on said frame, said arm being positionable in any one of multiple positions; means interconnecting said control arm and said ratio changing means for selecting one of multiple ratios depending upon the position of said control arm; a control arm idler wheel mounted on said control arm, said chain extending over said control arm idler wheel and forming an acute angle relative thereto, the resultant chain-tension force being in a direction to cause rotation of said control arm in a first direction; and tension means connected to said control arm for applying a force in a direction to cause rotation of said control arm in a second direction opposite to said first direction, said control arm being approximately in equilibrium for a selected chain tension in all of said multiple positions of said control arm.
Claim 3
Dependent Claim
37 words
An automatic shift control for a vehicle according to claim 1 wherein only a difference between actual chain tension and said selected chain tension causes rotation of said control arm in a direction to eliminate said difference.
Claim 4
Dependent Claim
58 words
An automatic shift control for a vehicle according to claim 2 wherein said control arm rotates in said first direction when the actual chain tension exceeds said selected chain tension by a predetermined amount and wherein said control arm rotates in said second direction when said selected chain tension exceeds the actual chain tension by said predetermined amount.
Claim 5
Dependent Claim
23 words
An automatic shift control for a vehicle according to claim 3 further comprising: means for selecting the value of said selected chain tension.
Claim 6
Dependent Claim
30 words
An automatic shift control for a vehicle according to claim 4 further comprising: means for selecting the value of said predetermined amount of difference between actual and selected chain tension.
Claim 7
Dependent Claim
30 words
An automatic shift control for a vehicle according to claim 3 further comprising: means for selecting the value of said predetermined amount of difference between actual and selected chain tension.
Claim 8
Dependent Claim
45 words
An automatic shift control for a vehicle according to claim 3 wherein said control arm includes a detent sector in one side edge thereof, said detent sector including a plurality of teeth defining notches therebetween, said notches defining said multiple positions of said control arm.
Claim 9
Dependent Claim
117 words
An automatic shift control for a vehicle according to claim 7 further comprising: a shift position detent arm mounted at one end thereof for rotation around a fixed point oN said vehicle frame, said control arm and said shift position detent arm rotating in parallel, spaced planes about parallel axes; a detent pin mounted on the other end of said detent arm and extending outwardly therefrom into one of said notches of said detent sector; and a spring connected to said other end of said shift position detent arm for biasing said detent arm with said detent pin in one of said detent notches, said detent arm holding said control arm in one of said multiple positions.
Claim 10
Dependent Claim
92 words
An automatic shift control for a vehicle according to claim 8 wherein the surfaces of said detent sector teeth are sloping so that said forces tending to cause rotation of said control arm in either said first or said second direction generate a component which tends to lift said detent pin out of said detent sector notches, movement of said detent pin out of said notches being resisted by the force of said spring, said spring thereby controlling the value of said predetermined amount of difference between actual and selected chain tension.
Claim 11
Dependent Claim
42 words
An automatic shift control for a vehicle according to claim 9 further comprising: means for selecting the value of said predetermined amount of difference between actual and selected chain tension, said selecting means comprising means for adjusting the tension of said spring.
Claim 12
Dependent Claim
151 words
An automatic shift control for a vehicle according to claim 9 wherein said control arm has an opening therein, positioned adjacent said detent sector, said control arm including a plurality of escapement teeth positioned opposite said detent sector teeth and extending into said opening in said control arm and further comprising: a release pin mounted on said other end of said shift position detent arm and extending outwardly therefrom, adjacent said detent pin, into said opening in said control arm, said release pin being positioned out of contact with said escapement teeth when said detent pin is positioned in one of said detent sector notches, said release pin moving into a position between adjacent escapement teeth as said detent pin moves from one detent sector notch to an adjacent detent sector notch to prevent further movement of said control arm until said detent pin is fully engaged in said adjacent notch.
Claim 13
Dependent Claim
130 words
An automatic shift control for a vehicle according to claim 9 further comprising means for preventing movement of said control arm except when said crank is in one of a limited number of selected positions, said control arm movement preventing means comprising: a disc-shaped detent release cam connected to said crank, the perimeter of said cam being perfectly circular except for at least one small notch therein; and a detent release cam follower mounted on said other end of said shift position detent arm, said cam follower contacting said perimeter of said detent cam, said circular portion of said cam preventing pivotal movement of said shift position detent arm with said detent pin being held in one of said notches of said detent sector, preventing motion of said control arm.
Claim 14
Dependent Claim
73 words
An automatic shift control for a vehicle according to claim 12 wherein said crank has a pair of opposed pedals connected thereto, said at least one notch in said detent release cam passing beneath said cam follower when one of said pedals is in a forward position, said detent arm being free to rotate to move said detent pin to an adjacent notch, said cam follower moving into said notch in said cam.
Claim 15
Dependent Claim
35 words
An automatic shift control for a vehicle according to claim 1 further comprising: means for preventing movement of said control arm except when said crank is in one of a limited number of selected positions.
Claim 16
Dependent Claim
43 words
An automatic shift control for a vehicle according to claim 14 wherein said crank has a pair of opposed pedals connected thereto and wherein said control arm movement preventing means prevents movement of said control arm except when said pedals are approximately horizontal.
Claim 17
Dependent Claim
50 words
An automatic shift contrOl for a vehicle according to claim 1 wherein said control arm moves between said multiple positions in a given sequence and further comprising: means for preventing movement of said control arm by more than one position in said sequence for each complete rotation of said crank.
Claim 18
Dependent Claim
77 words
An automatic shift control for a vehicle according to claim 1 wherein said chain extends around said crank, over said idler wheel, and around a gear mounted coaxially with said wheel and further comprising: at least one chain-engaging idler wheel fixedly mounted on said frame and positioned relative to said control arm so as to maintain a relatively acute chain angle over said control arm idler wheel in all of said multiple positions of said control arm.
Claim 19
Dependent Claim
95 words
An automatic shift control for a vehicle according to claim 17 wherein the length of said control arm, the position thereon of said control arm idler wheel relative to said fixed point on said frame, and said angle of said chain over said control arm idler wheel are selected so that as said resultant chain-tension force decreases, the moment arm through which said force acts increases at a rate such that the torque tending to cause rotation of said control arm in said first direction increases as said control arm rotates in said first direction.
Claim 20
Dependent Claim
59 words
An automatic shift control for a vehicle according to claim 18 wherein said tension means comprises: a spring connected between said frame and said control arm, said spring extending and applying a greater force to said control arm as said control arm rotates in said first direction, said increased force of said spring approximately balancing said chain-tension-induced increasing torque.
Claim 21
Dependent Claim
118 words
An automatic shift control for a vehicle according to claim 19 wherein said tension means further comprises: a pulley mounted on said frame; and a cable extending around said pulley and interconnecting said spring and said control arm, the position of said pulley relative to said control arm and the value of the force of said spring being selected so that as said force fo said spring increases, the moment arm through which said force acts changes at a rate such that the torque tending to cause rotation of said control arm in said second direction remains approximately equal to said chain-tension-induced torque for said selected chain tension in all of said multiple positions of said control arm.
Claim 22
Dependent Claim
23 words
An automatic shift control for a vehicle according to claim 19 further comprising: means for selecting the value of said selected chain tension.
Claim 23
Dependent Claim
32 words
An automatic shift control for a vehicle according to claim 21 wherein said means for selecting the value of said selected chain tension comprises: means for adjusting the tension of said spring.
Claim 24
Dependent Claim
62 words
An automatic shift control for a vehicle according to claim 1 wherein said rotation ratio changing means comprises a multiple gear derailleur mechanism connected to said at least one wheel and wherein said control arm provides the amount of slack required to permit engagement of all of the gears of said derailleur mechanism as said control arm moves between said multiple positions.
Claim 25
Dependent Claim
118 words
An automatic shift control for a vehicle according to claim 1 wherein said control arm has a cam surface on one side thereof and wherein said means interconnecting said control arm and said ratio changing means comprises: a shift control crank mounted for rotation around a fixed point on said frame, spaced from said control arm fixed point; a cam follower mounted on said shift control crank in position to rest on said cam sector of said control arm, rotation of said control arm causing rotation of said shift control crank; and a cable connected between said shift control crank and said ratio changing means for changing the selected one of multiple ratios as said control arm rotates.
References Cited (Backward Citations)
US3613466A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-29 | 1979-06-30 | 1979-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-29 | 1983-06-30 | 1983-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-29 | 1987-06-30 | 1987-12-30 | $7700.00 | Window Closed / Lapsed |