Machine element or mechanism – Control lever and linkage systems – Multiple controlled elements
Patent
1996-04-02
1998-08-04
Marmor, Charles A.
Machine element or mechanism
Control lever and linkage systems
Multiple controlled elements
74489, 745022, B62K 2302, B62M 2504, G05G 506
Patent
active
057877572
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
This invention relates to a bicycle speed change operation device which is provided at a suitable portion of a bicycle frame or handlebar for remotely operating a bicycle rear derailleur or a bicycle front derailleur via a cable.
BACKGROUND ART
In a bicycle which comprises a multiple rear gear having a plurality of diametrically different sprockets arranged in side by side relation (such a multiple rear gear being referred to as a multiple freewheel) as well as a multiple front gear having a plurality of diametrically different sprockets arranged in side by side relation (such a multiple front gear being referred to as a multiple chainwheel), a speed change may be performed shifting the chain to a selected sprocket of each multiple gear.
A device for shifting a chain to a selected sprocket of a multiple freewheel is called a rear derailleur, whereas a device for shifting a chain to a selected sprocket of a multiple chainwheel is called a front derailleur. In general, these derailleurs are designed to laterally press, in running, the endless chain between the multiple freewheel and the multiple chainwheel at a portion entering the multiple freewheel or the multiple chainwheel for shifting the chain to a target sprocket.
The element used for pressing a portion of the chain in this way is generally called a chain guide. The chain guide of the rear derailleur comprises an upper guide pulley and a lower guide tension pulley, whereas the chain guide of the front derailleur comprises a pair of guide plates arranged on both sides of the chain to sandwich it.
In general, the derailleur incorporates a parallelogram pantograph mechanism which is deformable for translating the chain guide. The parallelogram pantograph mechanism is always urged by a spring to return the chain guide toward a smaller sprocket.
A speed change operation of the derailleur, i.e., operation of deforming the parallelogram pantograph mechanism for laterally translating the chain guide, is performed via a cable by means of a speed change operation device mounted on the bicycle frame or handlebar. Most typically, the speed change operation device is in the form of an operation lever, and a control cable with its one end connected to the derailleur has its other end connected to the operation lever. Pivotal movement of the operation lever in one direction causes the control cable to be pulled, whereas pivotal movement of the operation lever in the opposite direction causes the control cable to be paid out. When the control cable is pulled, the pantograph mechanism is deformed against the spring force by as much as the cable is pulled. When the control cable is paid out, the pantograph mechanism is deformed under the restoring force of the spring by as much as the cable is paid out.
A speed change by the derailleur, i.e., a chain shift to a target sprocket of the multiple gear, occurs only when the chain guide moves to a lateral position corresponding to the target sprocket. Referring to FIG. 8, for example, when shifting the chain from the smallest sprocket S1 to intermediate sprocket S2 of a triple sprocket chainwheel CW, the chain guide need be moved from the position X1 corresponding to the smallest sprocket S1 to the position X2 corresponding to the intermediate sprocket S2. When shifting the chain to the largest sprocket S3, the chain guide need be moved to the position X3 corresponding to the largest sprocket S3.
In this way, for a chain shift by the derailleur, the chain need be brought to a limited range of positions for suitably shifting the chain to the target sprocket. Therefore, for enabling anyone to easily perform an appropriate speed change operation, a speed change operation device has been proposed which incorporates a built-in positioning mechanism to clickingly hold the lever stepwise at predetermined angular intervals. With such a speed change operation device, if the lever is pivoted to each stepwise engaging position, the chain guide is automatically brought to an appropriate position corresponding to the
REFERENCES:
patent: 4267744 (1981-05-01), Yamasaki
patent: 4744265 (1988-05-01), Nagano
patent: 4966046 (1990-10-01), Tagawa
patent: 5020387 (1991-06-01), Nagano
patent: 5390565 (1995-02-01), Tagawa et al.
Grabow Troy
Marmor Charles A.
Sugino Cycle Industries, Ltd.
LandOfFree
Bicycle speed change operation device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Bicycle speed change operation device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bicycle speed change operation device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1166352