Pedal-actuated bicycle gear shift means

Abstract

In bicycles having multi-speed gear arrangements, the automatic shifting of .Iadd.the sprocket chain controlling the .Iaddend.gears .Iadd.is .Iaddend.in response to foot pedal pressures .Iadd.and .Iaddend.is effected by fluid or electrical connections from the pedals to the .[.gear-changing.]. .Iadd.chain-shifting .Iaddend.mechanism.Iadd., .Iaddend.thereby to impart full foot control to shifting with resultant improved pedaling cadence and bicycling comfort.

I claim: 
     
       1. In a bicycle provided with front and rear sprockets defining multiple gears and a drive chain extending therebetween, .Iadd.a pair of foot pedals, .Iaddend.a shifting mechanism, means to effect shifting of the chain with respect to the gears, the improvement comprising: means cooperatively associated with the foot pedals of the bicycle for controlling the .[.gear-shifting.]. .Iadd.chain-shifting .Iaddend.means, said .[.pedal.]. .Iadd.pedal-associated .Iaddend.means including moveable elements on .[.the.]. .Iadd.a .Iaddend.pedal whereby movement of .[.the pedal.]. .Iadd.said moveable elements .Iaddend.to any one of a plurality of preselected positions .Iadd.by the application of varying foot pressure .Iaddend.will effect the requisite shifting of the chain with respect to the gears.   
     
     
       2. The improved chain shifting means of claim 1 wherein said .[.pedal.]..Iadd.pedal-associated .Iaddend.means includes a fluid cylinder mounted on .[.the.]. .Iadd.a said .Iaddend.bicycle pedal having a piston extending therefrom, a foot-engaged pedal plate on said pedal for shifting said piston, and a hydraulic line extending from said pedal-mounted cylinder to said shifting means, wherein said shifting means includes a .Iadd.further .Iaddend.fluid cylinder connected to said line. 
     
     
       3. The improved chain shifting means of claim 2 wherein said foot-engaged pedal plate is normally urged away from said .[.master.]. .Iadd.fluid .Iaddend.cylinder by yieldable means which is overcome by foot pressure thereagainst. 
     
     
       4. The improved chain shifting means of claim 3 wherein said .[.pedal.]. .Iadd.pedal-associated .Iaddend.means includes a frame carrying said .[.master.]. .Iadd.fluid .Iaddend.cylinder and said yieldably supported pedal plate is pivotally mounted on said frame. 
     
     
       5. The improved chain shifting means of claim 2 wherein said pedals are journalled for rotation on the crank arms of the bicycle and wherein said hydraulic line includes a swiveling connection between said .[.pedal.]. .Iadd.pedals .Iaddend.to a fluid conduit associated with said crank arm. 
     
     
       6. The improved chain shifting means of claim 2 wherein each said pedal .[.means.]. of the bicycle is provided with a said fluid cylinder and hydraulic line connections commonly connected to said .[.gear.]. shifting .Iadd.further .Iaddend.fluid cylinder. 
     
     
       7. The improved chain shifting means of claim 2 further including a valve to block flow to and from said pedal .Iadd.fluid .Iaddend.cylinder thereby to disable said fluid-controlled .[.gear.]. .Iadd.chain .Iaddend.shift operation. 
     
     
       8. The improved chain shifting means of claim 2 including a hydraulic fluid reservoir communicating with said hydraulic line. 
     
     
       9. The improved chain shifting means of claim 8 wherein said reservoir is disposed within a frame member of the bicycle and communicates with said hydraulic line at the crank axle hub of the bicycle. 
     
     
       10. The improved chain shifting means of claim 2 wherein said hydraulic line extends through the crank arms and crank hub of the bicycle. 
     
     
       11. The improved chain-shifting means of claim 1 wherein said .[.gear-shifting.]. .Iadd.chain-shifting .Iaddend.means is electrically actuated. 
     
     
       12. The improved .[.gear-shifting.]. .Iadd.chain-shifting .Iaddend.means of claim 11 wherein an electric solenoid effects shifting of said .[.gears.]. .Iadd.chain .Iaddend.and wherein said movement of said .[.pedals.]. .Iadd.moveable elements .Iaddend.regulate current to the said .[.gear-shifting.]. .Iadd.chain-shifting .Iaddend.solenoid thereby to determine the extent of movement thereof in shifting the .[.gears.]. .Iadd.chain.Iaddend.. 
     
     
       13. The improved .[.gear-shifting.]. .Iadd.chain-shifting .Iaddend.means of claim 12 wherein a plurality of resistance elements are provided for each said foot pedal and wherein movement of said .[.foot pedal.]. .Iadd.moveable elements .Iaddend.selects a predetermined resistance element thereby to control .[.gear-shifting.]. .Iadd.chain-shifting .Iaddend.movement of said solenoid. 
     
     
       14. The improved .[.gear-shifting.]. .Iadd.chain-shifting .Iaddend.means of claim 13 wherein alternate sequential switch means are provided for each said foot pedal thereby to disable the electrical system of each pedal during a portion of its rotation.