Improvements in Sprocket Wheels and Chains.
Year: 1897

page_text: Date of Application, 15th Mar., 1897-Accepted, 17th Apr., 1897
Improvements in Sprocket Wheels and Chains.
A communication from abroad by JOHN C. COTTIE, of the City, County, and State
of New York, United States of America, Machinist, and CHARLES J. MARKS,
of Brooklyn, King's County, State of New York, United States of America,
Machinist.
I, WILLIAM LLOYD WISE of 46 Lincoln's lan Fields, in the County of
London Consulting Engineer and Chartered Patent Agent do hereby declare
the nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
This invention relates to an improvement in sprocket wheels and chains therefor,
particularly adapted for use in connection with bicycles, but which may be employed
with equally good results wherever a sprocket chain and wheel are needed, especially
for driving purposes. The object of the invention is to provide a sprocket wheel
with rolling surfaces for engagement with the chain, and to so construct the chain
that it will accommodate itself to wheels of different circumferences whereby the
teeth on the chain will have perfect clearance on entering and leaving a large or a
small wheel. A further object of the invention is to provide a chain which will be
light, economical, durable and compact, and also to provide a wheel having flanges
between which the roller surfaces are placed, whereby the wheel will be self-
cleaning, and the chain when passing over the wheel will be practically flush with
the outer edges of the flanges.
The invention consists in the novel construction and combination of the several
parts, as will be hereinafter fully set forth and pointed out in the claims.
Reference is to be had to the accompanying drawing forming a part of this
specification, in which :-
Fig. 1, is a side elevation of a large and a small wheel and a chain passing over
the two, a portion of the large wheel being broken away.
Fig. 2, is a section through the large wheel, taken substantially on the line 2-2,
of Fig. 1.
Fig. 3, is a circumferential view of the small wheel.
Fig. 4, is a bottom plan view of a section of the chain.
In carrying out the invention, the wheel A, is preferably constructed of a series
of rings 10, which are bolted or riveted together, or secured together in any
suitable or approved manner at or near their peripheries. The centermost ring is
provided with inwardly extending lugs 11, whereby the wheel may be attached to a
suitable hub, but the lugs 11, may be omitted and said ring otherwise connected to
the hub or formed integral therewith.
A flange 12, is formed or otherwise provided on each side of the peripheral
portion of the wheel, here they are shown as continuations of the outermost
rings 10. The flanges 12, are preferably provided with openings 13, as shown
in Figs. 1 and 2, to facilitate the escape of dust or any foreign material that would
be liable to lodge in the space between the flanges.
Preferably cleats or prongs 14, three in number grouped substantially as shown,
are formed upon the periphery of the wheel between the flanges thereof, and within
each group of cleats a ball 15, is held to revolve. The balls are substitutes for the
usual teeth of a sprocket wheel, and may be held to revolve at the periphery of the
wheel in other ways than that illustrated.
The chain B, consists of links 16, each alternate link being double and the
connecting links single as shown in Fig. 4. Each link is provided with a tooth 17,
₹
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page_text: formed upon its under face, and the side edges of the teeth are concaved. When
the chain is used as an element in multiplying gear, the teeth 17, are not centrally
located on the links but are placed at one side of the transverse center of said links,
so that when the links are pivoted together, as shown in Fig. 1, alternately large
and small segmental pockets 18, are formed between the teeth of the links. In this
way the chain is better adapted to the usual combination of large and small wheels,
the larger pockets receiving the balls or rolling surfaces of the smaller wheel and
the smaller pockets those of the larger wheel, as is clearly shown in Fig. 1.
Where the driving and driven wheels are of the same size, the teeth 17, will be
formed in the middle of the links and the pockets made equal.
The construction described insures a high rate of efficiency, the driving friction
being reduced to the minimum.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A sprocket wheel provided with cleats arranged in groups upon its periphery,
and a ball held to revolve within each group of cleats, as and for the purpose set
forth.
2. A sprocket wheel constructed of a series of rings, secured together, a flange
formed at each side of the peripheral portion of the wheel, bearings located in the
space between the flanges of the wheel, and rolling surfaces mounted to turn in
the said bearings, substantially as shown and described.
3. A sprocket wheel constructed of a series of rings secured together, the center
ring being provided with inwardly extending lugs, a flange formed at each side of
the peripheral portion of the wheel, the said flanges being continuations of the
outer rings and provided with openings, and rolling surfaces located between the
said flanges, as and for the purpose specified.
4. A sprocket chain the links whereof are provided with teeth, the said teeth
having their centers at one side of the centers of the links with which they are
connected to form alternately large and small pockets, as and for the purpose
specified.
5. A sprocket chain consisting of a series of links, each alternate link being
double and the connecting links single, each of said links being provided with a
tooth formed upon its inner face and baving its side faces concaved.
6. The combination with the sprocket wheel having balls mounted to revolve on
its periphery, of a chain, the links whereof are provided with teeth at their inner
edges, the said teeth having their side edges concaved to engage the balls, as and
for the purpose set forth.
7. The combination with a pair of sprocket wheels of unequal size having balls
mounted to revolve on their peripheries, of a chain the links whereof are provided
with teeth at their inner edges, the center of the said teeth being at one side of the
center of the links to which the teeth belong, whereby alternating pockets of
different dimensions are formed, the said pockets being adapted for the reception
of the spherical rotating surfaces of the respective wheels, as and for the purpose
set forth.
8. A sprocket wheel having bearings formed upon the periphery, and balls
mounted to revolve freely in the bearings, the said bearings permitting of the
exposure of a major portion of the balls for engagement with the teeth of a
sprocket chain, whereby the balls are freely revolved, as and for the purpose
specified.
9. The chain and sprocket wheels, substantially as shown and described.
Dated th
1
CAC
1007
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.