Claims
- 1. A system for shifting between different drive ratios on a bicycle, comprising:means for aligning a portion of a drive chain of the bicycle with one of a plurality of sprockets attached to the bicycle, said aligning means including a hydraulic actuator; a hydraulic pump; and control means for selectively applying hydraulic pressure from said pump to said hydraulic actuator.
- 2. The system of claim 1 wherein said hydraulic pump is coupled to a sprocket engaging the drive chain, such that said pump operates only when the drive chain is moving.
- 3. The system of claim 2 herein said sprocket is a chain guide sprocket coupled to said aligning means.
- 4. The system of claim 2 wherein said sprocket is an idler sprocket in a chain idler arm assembly of the bicycle which imparts slack tension to the drive chain.
- 5. The system of claim 1 wherein said hydraulic pump is a gerotor-style pump.
- 6. The system of claim 1 further comprising a fluid reservoir in communication with said hydraulic pump.
- 7. The system of claim 6 wherein:said control means includes a hydraulic spool control valve; and said reservoir and said hydraulic spool control valve are integrated into a single assembly.
- 8. The system of claim 1 wherein:said aligning means includes a rear derailleur and a front guide; and said control means includes means for applying hydraulic pressure from said pump to a selected one of said rear derailleur and said front guide.
- 9. The system of claim 1 wherein:said hydraulic actuator has first and second ports; and said control means moves said hydraulic actuator in a first direction of decreasing gear ratios when hydraulic pressure is applied to said first port, and said control means moves said hydraulic actuator in a second direction of increasing gear ratios when hydraulic pressure is applied to said second port.
- 10. The system of claim 1 wherein said control means is operated by a remote shifter.
- 11. The system of claim 10 wherein said remote shifter is in fluid communication with said control means to hydraulically operate said control means.
- 12. The system of claim 10 wherein said remote shifter is a first remote shifter located at a first position on a handlebar of the bicycle and wherein said control means is further operated by a second remote shifter located at a second position on said handlebar.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of copending U.S. patent application Ser. No. 09/137,219 filed on Aug. 20, 1998 now U.S. Pat. No. 6,042,495, which is a continuation-in-part of U.S. patent application Ser. No. 08/997,973 filed Dec. 24, 1997, now U.S. Pat. No. 6,012,999.
US Referenced Citations (12)
Continuations (1)
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Date |
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09/137219 |
Aug 1998 |
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Child |
09/519200 |
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Continuation in Parts (1)
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08/997973 |
Dec 1997 |
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09/137219 |
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