Improvements in Chain Gearing.
Year: 1896

page_text: Improvements in Chain Gearing.
I JOHN FAVETS of 103 Hatton Garden in the City of London, Commission Agent,
do hereby declare the nature of my said invention to be as follows:-
My invention relates more particularly but not exclusively, to chains for use with
elliptical, eccentric or analogous sprocket wheels and consists in the construction
and arrangement of such chains whereby the slackness of the chain, when the
longer foci of the elliptical wheel is in the same direction as the chain, is
automatically taken up and kept taut.
According to my invention, I form the side plates of the chain links after the
manner of truss girders, each pair of struts being provided with a piu or stud,
connecting the two, which acts as the bearing or contact surface to which power is
applied. These pins or studs vary in position relatively to the strut so that each
pin or stud accommodates itself to the position of the corresponding tooth of the
sprocket wheel. The latter is provided with a circular boss or drum mounted
centrally on each side on which the lower portion of the links rest, whereby the
weight of the chain is removed from the teeth of the sprocket wheel, and the chain
caused to travel concentrically with the axis of the sprocket wheel.
The side plate of the cliain may be formed with a vertical strut and two
diagonal links pivoted or otherwise attached to the strut, each chain link consisting
of two such plates and the connecting contact stud; other convenient shapes or
constructions of links may also be used the essence of the invention being the
varying position of the contact stud relatively to the strut in order that its position
inay coincide with the position of the tooth of the sprocket wheel with which such
stud is intended to gear.
Improvemen
aring.
I, JOHN FAVETS, of 103 Hatton Garden, in the City of London, Commission
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:-
According to my invention I make use of a chain gear comprising an elliptical,
eccentric or analogous sprocket wheel suitably mounted to the frame of the macline

page_text: for which the gear is designed, and adapted to drive another sprocket wheel,
preferably of circular form, through the intervention of a chain of special con-
struction, the arrangement being such that the chain will always bo kept tight
irrespective of the position which the two wheels may occupy.
In order that my said invention may be readily understood I will proceed to
describe the same with reference to the accompanying drawing, showing a side
elevation, partly in section, of an improved gear which comprises an elliptical
sprocket wheel.
A designates the elliptical driving wheel, B the circular driven wheel, and C the
chain. The links of this chain C form crosses and their pins or bars a b c d e f
which are desigued to engage with the teeth ce¹¹of the wheel A and
which may be furnished with rollers if desired, are placed at varying heights above,
at and below the pitch line of the chain as shown. According to the shape of the
ellipse formed by the pitch line of the sprocket wheel A the teeth ce
are made of varying depth. Between the lowest pins a and the highest pins e
and there may be four or any number of heights for the intermediate pins
corresponding to the teeth between the minor and major axis of the ellipse
constituting the pitch line of the sprocket wheel. On each side of the wheel A is
furnished a shoulder against which the base of the chain link will bear in order
that the pins or bars of the latter may properly engage with the corresponding
teeth of the said wheel.
g
The chain C gears with the teeth of the second sprocket wheel B by means of its
pivots h, the intermediate spaces between the teeth being made of sufficient depth
to afford free space for the before-mentioned pius or bars a bedef of the chain.
It will be easily understood that in lieu of the elliptical wheel described I may
employ an eccentric or similar wheel.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
First. A chain gear comprising the combination of an elliptical, eccentric or
analogous sprocket wheel A, a circular sprocket wheel B, and a chain C adapted to
gear by its pins or bars a be def with the teeth beef of the wheel A,
and by its pivots with the teeth of the wheel B, substantially as herein before
set forth.
h
Second. In combination with the sprocket wheels A and B a chain C having
cross pins or bars a b c d e f arranged at varying heights, substantially as herein-
before set forth.
Third. In a chain gear the combination, with an elliptical, eccentric, or analogons
sprocket wheel A, of a chain C, the links of which form crosses provided with pins
or bars b which are arranged at varying heights, and have their bases adapted
to bear against shoulders y on the said wheel, substantially as herein before set
forth.
Fourth. A chain constructed and operating substantially as and for the purpose
herein before specified with reference to the accompanying drawing.
Dotal this 24th day of Annil 1907