WO1989009157A1 - Easy-to-pedal bicycles - Google Patents

Abstract

An improved bicycle pedal mechanism for performing direct transmission of pedaling power from pedal cranks (12) to a rim of big gear (15) for lighter, easier turning of a rear wheel with much less efforts of a bicyclist than on prior art, which provides pedal mechanism for performing transmission of pedal power from pedal cranks (12) to the big gear (14) through the crank axle (17), requiring more efforts and causing the crank axle to be vulnerable to damage, comprises a big gear (15) being enlarged in radius as much to the length of a right foot crank (12) as appropriate, a connector (13) being fixed between a spot near said big gear sprockets and said right foot crank (12) closeby, a round detachable chain cover (16) sticking to said big gear (15). A single speed free gear (18) in a rear wheel hub is enlarged to 6 or 7 centimeters in radius as appropriate, as said big gear is enlarged for further lighter turning.

Description

DESCRIPTION 1

EASY-TO-PEDAL BICYCLES

Technical Field

This invention relates to bicycles, or similar cycles, specifically to an improved pedal mechanism for a bicyclist to be able to pedal with much reduced efforts.

Background Art

-Most bicyclists find that there is still rocm for improvement in pedal system. They find it hard to pedal up even little slopes and have to push their bicycles up to the hilltops most of times. They also find it too often to pedal and e_φerience their bicycles suffer damages to the crank axles after long ride due to excessive stresses to the crank axles.

Heretofore a wide variety of pedal mechanism has been proposed and implemented for easy pedaling. It seems that pedal cranks are fixed to a crank axle alone to give easy twisting to the big gear somewhat in accordance with the principle of the wheel and axle. One such mechanism consisted of one limited, 48-toothbed big gear with right and left foot cranks linked to the hub of said gear and one 15-toothbed free gear in the hub of a rear wheel. Other latest edels consisted of one limited, 48-toothbed big gearhaving sprockets in two rows with both pedal cranks connected to the hub of said gear and five free gears (15 through 28 toothbed) in the hub of said rear wheel for much easier pedaling at variable cycling ratios. The way the mechanism set up indicates that pedaling power should be transmitted to said rear wheel through cranks, crank axle, big gear sprockets, chain, and through free gear. So the one-way connection of the cranks to the hub of said big gear is 2 responsible for hardship in pedaling and damage to the crank axle. Bicyclists are really afraid if the cranks should be broken, when they pedal up hard on steep slopes. Most bicyclists, therefore, would find it desirable to have a bicycle so improved, durable that they could continue to pedal up any uphill roads and go on plain roads lightly, effortlessly, and pleasantly at variable ratios from two to more than four cycles of free gears to one cycle of said big gear.

Disclosure of Invention

This invention is developed in compliance with a natural law, the principle of the wheel and axle like a lever to turn a big gear (15) most efficiently and effortlessly, thereby satisfying the bicyclists' wishes. The big gear (15) will be enlarged within the length of a right foot crank, depending on one's taste, and have a connector (13) fixed between a spot near the sprockets of the big gear (15) and the right foot crank (12) closeby to serve as a means for transmitting pedaling pcwer directly to the rim of the enlarged big gear (15) . Five speed free gears will also be enlarged in radius as appropriate to maintain proper ratios of cycling to that of the big gear. The smallest speed free gear may remain the same to give more cycling ratio to that of the big gear. One of the speed free gears may be large enough to give a ratio of one and one-half cycle to a cycle of the big gear for use on steep slopes and free rolling. To meet the principle of the wheel and axle, which says briefly that a larger wheel is easier to turn by the rim than to turn a smaller one by the rim when both wheels are fixed together on an axle, big gear (15) and free gears (18) are enlarged as appropriate, thereby giving a more ratio of cycles of free gears to a cycle of a big gear and lightening pedaling power, as pedaling power acts on the rim of the big gear through the connector (13). This applicant had a 5-speed bicycle reinforced according to the invention. A big gear has been enlarged frcrn 52 to 65 sprockets (10 to 12. 5 centi meters in radius) and the largest speed free gear from 28 to 32 sprockets (5.4 to 6.1 centi meters) and a connector has been fixed between a sport near the sprockets of the big gear and the right foot crank closeby. The improved mechanism gives the applicant a driving pleasure with much less effort. The applicant could pedal up with ease any steep slopes in the cαπ uity, same of which he couldn't do on prior art. The pedaling power just acts right on the rim of the enlarged big gear and turns the big gear much easily, enabling to give a quick push to the rear wheel for quicker pace. He is surprised to notice that he doesn't need any more efforts to push the left foot pedal than to push the right foot pedal. As long as a spot of the rim of a big gear is connected to the pedal crank, a left foot pedaling power that is trans- mitted to the rim of the big gear through the crank axle and the rihgt foot crank is as strong as the right foot pedaling power that is trans¬ mitted directly to the rim. He could go up an uphill road at the ratio of two cycles of the 32 toothbed free gear to a cycle of the 65 toothbed big gear and on plain or descending roads at the ratio of more than four cycles of the smallest (15 toothbed) free gear to a cycle of 65 toothbed big gear, thus saving much energy and keeping the crank axle frσn damage

Another experience disclosed that a connection only between a spot near the sprockets of a big gear and a right foot crank of a prior art,without a big gear and free gears enlarged, enabled the bicycle to perform almost as efficiently as this invention.

Now bike lovers can truly enjoy the essence of such handy, convenient transportation means as this most improved bicycle.

This applicant, therefore, claims the following as his object and advantages of the invention to provide an improved pedal system which 4 enables a bicyclist to pedal up a five speed free gear bicycle on all the steep slopes of any kind without getting off, to provide the system for bicycles running with heavier load, to provide the system for a rear wheel running faster on plain roads at the ratio frcm two to four cycles to one cycle of a big gear, to provide the system which protects bicycles frcm any c3__mages to the crank axles, to provide the system for bicycles servingfor travel, sport activities, and for health.

Readers will find further objects and advantages of the invention frcm a consideration of the ensuing description and the acccmpaning drawings.

Brief Description of Drawings .

Fig 1 shows a perspective side view of pedal mechanism according to the invention.

Fig 2 shows a sectional view of such a pedal mechanism frcm the rear of a bicycle.

Drawing Reference Numbers

11 pedal

12 crank

13 connector between sprockets and right foot crank

14 big gear of prior art 15 big gear (enlarged) of invention

16 chain cover

17 crank axle

18 free gear

Best Mode for Carrying Out the Invention

A bicycle has an improved pedal mechanian comprising an enlarged big gear (15) of 14 centi meters in radius being connected to a right foot crank through a spot (13) near the sprockets of said big gear (15) and an enlarged free gear (18) of seven centi meters in radius in order to provide the bicycle for transmitting pedaling power directly to the rim of the enlarged big gear for lighter, easier turning of the rear wheel in accordance with the principle of the wheel and axle. F ve speed free gears (18) in the hub of a rear wheel cure enlarged to 4, 5, 6. 7 centi meters in radius except the smallest one, which remains 2.9 centi meters as on prior art in order to give more cycles to a cycle of the big gear on plain or descending roads. A round and detachable chain cover (16) sticks to the big gear.

While the above description contains one specificity the reader should not construe it as limitations on the scope of the invention, but merely as exemplifications of preferred embodiments thereof. Those skilled in the art will envision many other possible variations are within its sccpe. For exaπple skilled artisans will readily be able to change the dimensions and shapes of the various embodiments. They can make the single free gear as big as the big gear for ccmpletely free pedaling with the crank connection to the rim of said big gear. They can make a big gear just connected to a right foot crank through a spot near sprockets without having the big gear and free gears enlarged. Accordingly the reader is requested to determine the sccpe of the invention by the appended claims and their legal equivalents, and not by the exanples which have been given.

Claims

1. An improved bicycle pedal mechanism for performing direct trans¬ mission of pedaling power frcm pedal cranks (12) to a rim of a big gear

(15) comprising said big gear (15) being enlarged in radius within the 5 length of a right foot crank (12) as appropriate and having its rim (13) connected to said right foot crank closesby, means for transmitting said pedaling power directly frcm said right foot crank (12) to the rim of said big gear (15) for easy turning of said big gear with less efforts of a bicyclist; 10 A round, detachable chain cover (16) sticking to said big gear (15)and A single speed gear (18) in the hub of a rear wheel being enlarged to a measurement in radius as appropriate, as said big gear (15) is enlarged.

2. The improved bicycle pedal mechanisn of claim 1 wherein the hub of said rear wheel comprises five speed free gears (18) being enlarged as

^5 appropriate in relation to the enlargement of said big gear except the smallest free gear.