Improvement in Chain Sprocket Wheels.
Year: 1896

page_text: Improvement in Chain Sprocket Wheels.
JOHN FRANCIS DOWLING, Tolka Vale, Finglas, Co. Dublin, Mattress Maker,
do hereby declare the nature of this invention to be as follows:-
The improvement consists of making the wheel and teeth in seperate parts.
The blank wheel disc has suitable recesses or sockets in its periphery which are
either left in at the time of manufacture or are afterwards shaped out. The
teeth of either metal or of wood or of a compressed substance are then secured
into these recesses or sockets which may be of any shape. In case they are
preferred round they may be tapped and the teeth screwed in. By this means
the teeth may be renewed as often as is desirable.
Dated this Ninth day of December 1896.
I, JOHN FRANCIS DOWLING, Tolka Vale, Finglas, in the County of Dublin,
Wire Mattress Manufacturer, 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 for improved chain sprocket wheels consists in making the
wheels for cycles, motor cars, and the like with receptacles or mortices in their
peripheries into which the teeth are inserted.
These latter may be of any suitable material, either wood, metal or a compressed
substance.
By this means whenever the teeth become worn, they can be replaced by new
ones without discarding the whole wheel. Where they are made of, for instance,
beech, oak, or other hard wood, the wear on the chain is considerably reduced
as well as the weight of the wheels.
In the accompanying sheet of illustrative drawings, Fig. 1 is an elevation of a
sprocket wheel constructed according to this invention. Fig. 2 is a transverse
section of the same, Fig. 3 is a similar view to Fig. 1 with some of the outer
parts removed and Figs. 4, 5, 6 and 7 are detail views.
A disc a preferably of metal is formed with dovetail or similar tapering
cavities b, in its periphery, contracting outwardly, and shrouded by two face
plates e secured to each side of said disc by bolts d, rivets or other suitable means.
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page_text: The face plates c are bored with a small hole e near the bottom of each cavity b,
and parallel with the axis of the wheel, through which a wedge or pin f is driven
for securing wood or metal teeth g in the peripheral openings b, by expanding
their bases against the tapering sides of said cavities b and thus preventing
their withdrawal.
In a modified form of construction the teeth g are screwed into the periphery
of the disc a which is tapped with suitable holes f for their reception, no face
plates being required, and a pin f driven in at the base to lock the tooth in
position.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is :-
1. A chain sprocket wheel consisting of a disc formed with peripheral cavities
contracting outwards, faceplates for shrouding the cavities, teeth for inserting
in said cavities and pins or wedges securing the teeth in position, substantially
as described.
2. A chain sprocket wheel comprising a disc having tapped holes in its periphery
and corresponding teeth adapted to be secured therein, the whole substantially
as described.
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WHEATLEY & MACKENZIE,
40 Chancery Lane, London, W.C., Agents.