An Improvement in Sprocket Wheels to be used in conjunction with Anti-friction or Ball-carrying Chains for Cycles or other pur- poses.
Year: 1897

page_text: Date of Application, 1st May, 1897
Complete Specification Left, 1st Mar., 1898-Accepted, 9th Apr., 1898
PROVISIONAL SPECIFICATION.
An Improvement in Sprocket Wheels to be used in conjunction with
Anti-friction or Ball-carrying Chains for Cycles or other pur-
poses.
:―
I, GERALD WILLIAM LAYBOURN, of 4, Woodland Street, Tunstall Staffordshire,
Potters Manager, do hereby declare the nature of this invention to be as follows:-
This invention relates to an improvement in sprocket wheels, and has for its
object, the distinct and peculiarly shaped, radial teeth or sprockets and described
as follows: I so make the sprocket wheels, that each radial tooth or sprocket,
shall have on both its inside surfaces, or facets, a suitable curve of any size, or shape,
to correspond with the contour, of the balls, of any size, according to the ball
used in any anti friction chain. I also make the radial teeth or sprockets, of any
given size, or shape, at the base or extremity of same, according to the size or
shape of curve to be given to its facets, to correspond with the contour, of the
balls used in any anti friction driving chain.
Dated this First dow of Mo 1807
3 An Improvement in Sprocket Wheels to be used in conjunction with
Anti-friction or Ball-carrying Chains for Cycles or other pur-
poses.
I, GERALD WILLIAM LAYBOURN, 4, Woodland Street, Tunstall, Staffordshire,
Potters Manager, 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 my invention has reference to sprocket-wheels having an improved form
of teeth and chiefly intended for use in combination or conjunction with anti-
friction ball or roller driving chains used with cycles, bicycles, tricycles motor-
cars and similar carriages, the object of my said invention being to reduce friction,
prevent slip and make such wheels more efficient for the purposes named than
sprocket wheels usually used.
In carrying my said invention into practice I make such improved sprocket-
wheels of any suitable size, and with any suitable number of teeth by first making
a pattern of the size required from any suitable wood or other suitable material,
making a mould from such pattern and casting such wheels in iron, brass,
CD 071

page_text: manganese-bronze, phosphor-bronze, malleable steel or like suitable metal or metal-
lic alloy, or such wheels may be forged, and afterwards turned and filed or other-
wise machined or finished.
Each (radial) tooth of such improved sprocket-wheels I make of suitable width
at their base, and the end or root surface of each of such (radial) teeth of suitable
curvature to conform to the periphery or outer surface of the balls or rollers in
the anti-friction chain or chains used.
In order that my said invention may be more readily understood and explained
in detail I have hereunto annexed a sheet of drawings on which letters of refer-
ence are marked on corresponding parts on all the figures alike.
DESCRIPTION OF DRAWINGS.
Figure 1 is a side elevation of an improved sprocket-wheel made according
to my invention.
Figure 2 is a plan view of Figure 1.
Figure 3 is a side elevation of a companion or gear wheel used in conjunction
with that shewn at Figure 1 for bicycles or like vehicles, and Figure 4 is an
enlarged side elevation of one of the teeth of such improved sprocket-wheels.
On reference to the drawings hereto annexed a represents the hub of such
improved wheels around which are the several arms b and their peripheral rim c
on which the several teeth d are cast or formed.
When sprocket-wheels such as described are fixed to suitable shafts or spindles
a portion of the periphery of each ball or roller of the endless anti-friction
chain used loosely fitting around the circumference of such wheels as such
wheels are rotated by foot or other power will be caught or pressed against
by the curve e at the base of each advancing tooth of such wheels according to
the direction of rotation, the upper or outer end f of each tooth I bevel or
taper to ensure the entrance of such teeth between the spheres or rollers of such
chain as such wheels and anti-friction chain are rotated or revolved.
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:
The construction of metallic sprocket wheels for use in combination with the
anti-friction chains of bicycles, tricycles, motor-cars and like vehicles of various
or different sizes with any suitable number of teeth of suitable size according to
the pitch or distance apart of the spheres, balls or rollers of the said anti-friction
chains, the radius of the curvature at the root or base at each side of each tooth
of such sprocket-wheels conforming to, or approximately conforming to or with
the radius of the balls, spheres or rollers of such anti-friction driving chains
as herein substantially described set forth and illustrated on the drawings hereto
annexed.
JOHN NEWTON,
Longport, Stoke-on-Trent, Staffordshire, Agent for Applicant.