US578260A

US578260A - James oag and john mcdonald

Info

Publication number: US578260A
Authority: US
Publication date: 1897-03-02
Anticipated expiration: 1914-03-02

Description

(No Model.) l

J. OAG J. MODONALD. DRIVING GEAR FOR BIGYGLES.

No. 578,260. Patented Mar. 2, 1897.

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PV L'/CQSSQ@ VW @RM1/A2M@ UNITED STATES l PATENT OFFICE.

JAMES OAG AND JOHN MCDONALD, OF TORONTO, CANADA.

DRIVING-G EAR FOR BICYCLES.

SPECIFICATION forming part of Letters Patent No. 578,260, dated March 2, 1897'. Application filed May 8,1896.` Serial No. 590,742. (No model.)

/o LZZ whom, it may concern;

Be it known that we, JAMES OAG, blacksmith, and JOHN MCDONALD, machinist, of the city of Toronto, in the county of York and Province of Ontario, Canada, haver'invented a certain new and Improved Driving-,Gear for Bicycles, of which the following is a specification.

The object `of our invention is to devise a crank-and-lever driving-gear for bicyclists in which the possibility of sticking on a deadcenter is obviated; and it consists, essentially, of a bent lever pivoted on the frame, its long arm havin g a pedal connected thereto and its short arm connected by a pitman to 'a crank on the axle of the ordinary driving sprocket-wheel of the bicycle, a buffer being so connected to the long arm of the lever as to come into contact with the pitman when the crank is on a dead-center and so throw it over the center, substantially as hereinafter more particularly described and then definitely claimed.

Figure l is a side view of a bicycle provided with our improved driving-gear. Fig. 2 is an enlarged detail and side elevation of the driving-gear, showing the crank passing over the dead-center. Fig. 3 is a detail in elevation of the spring-buffer.

In the drawings like letters of reference indicate corresponding parts in the different figures.

A is a bent lever pivoted at-ct to the frame 0f the bicycle. To the long arm .B of this lever is connected the pedal l).

O is the short arm of the lever, to which is pivoted one end of the pitman D, the other end of the said pitman being journaled on the crank E, which is fast on the axle of the ordinary driving sprocket-wheel F of the bicycle. This sprocket-Wheel is geared in the ordinary manner to the rear wheel 0f the bicycle, as indicated.

Although we speak of a separate crank-arm being provided on the axle of the sprocketwheel F, yet a wrist-pin 'on one of the spokes of the sprocket-wheel would answer the purpose of ourinvention, the separate crank-arm being only necessary on the other side of the frame, where of course all the driving parts are duplicated.

G is a bolt adapted to slide through the lug As shown in Fig. 2, when the cranks E are on the dead-center the end of the bolt G comes in contact with the pitman D and thus applies a yielding pressure to it to throw the crank over the dead-center. Of course if the position of the bolts G were very accurately determined it might be possible to dispense with the coil-spring I; but in practice it is found preferable to use the spring, as jarring of any kind is thus obviated. We consider this buffer a most important feature of our invention, as in practice it is found, especially when starting, that there is great danger of the cranks striking on the dead-center and of the rider, by pressure on the pedals, bending or otherwise damaging'the frame of the bicycle. When the buffers are used, however, the down lever just nicely starts the cranks off the dead-center, and the rider is enabled to tell by the feel of the mechanism when it is safe to apply all his power on the downstroke of the other lever. n

As it is desirable to change the gear of the bicycle to suit different riders or to suit different conditions of roads under which the' bicycle is to be ridden, we provide the short arm c of the bent lever a with a series of holes, in any one of which the pitman D may be pivoted.

From the above description it will be seen that we have invented a very simple and effective up-and-down driving-gear for bicycles in which no toothed wheels or ratchets are used and in which no springs are required to return the levers to their raised position after a stroke of the foot. It Will'also be seen that we have invented a very effectivel method of preventing all danger of the gear striking on the dead-center and thus rendering the bicycle liable to injury.

It should be mentioned that the nature of the spring-bulfer is immaterial, as a rubber block, a flat sprin g, or any other form of IOO spring might be used instead of the springbolt shown.

What We claim as our invention is- In a bicycle, the combination with the bent lever A, pivoted to the frame of the bieyele; the pedal b connected to the long arm B of the bent lever; the crank E connected with the axle of the driving sprocket-Wheel F of the ordinary gearing; and the pitnian D connecting the said crank With the short arm C of the bent lever and situated under said bent lever; of a builer connected with the long arm of said bent lever and constructed and arranged to come into Contact with the pitlnztn D and throw the Crank over the dead I5 center when the said bent lever approaches the said pitlnztn, substantially as and for the purpose specified.

Toronto, April 30, 1896.

JAMES OAG. JOHN MCDONALD. In presence of J. EDW. MAYBEE, A. M. NEFF.