Improvements in and relating to Driving Gear for Velocipedes, and Gear Cases therefor.
Year: 1897

page_text: Improvements in and relating to Driving Gear for Velocipedes, and
Gear Cases therefor.
We, CONSTANT ALPHONSE CHEVALIER and NORBERT GUSTAVE VASSEUR, both of
No. 6, Rue Singer, Caen (Departement du Calvados), in the Republic of France,
Mechanical Engineers, do hereby declare the nature of this invention to be as
follows:-
-
Our invention relates to a novel form of driving or crank axle for velocipedes
in combination with a gear case or chain cover which is detachable but hermeti-
cally closed.
The essential characteristic of the crank axle is that its chain wheel is arranged
between the ball bearings thereby securing a normal tractive action of the chain
or other transmitting device, preventing all twisting action and increasing the
rigidity of the machine. In addition to this a detachable gear case surrounds
each length of the chein separately and connects with the crank axle socket and
with the hub of the driving wheel in such a manner as to form two hermetically
closed boxes around the chain wheels.
Upon the crank axle is rigidly fixed between the ball races on opposite sides,
the chain wheel. In order that this arrangement may not cause the introduction
of dust into the bearings situated upon the same side as the chain wheel, the
socket or bottom bracket of the crank axle is rigidly connected with a metal
case which surrounds the chain wheel and also the bearing cups and cones.
The hub of the rear wheel of the machine is likewise rigidly connected with
a case which surrounds the chain wheel and the corresponding bearing.
Two gear case arms or sections connect with the chain wheel cases at the hubs of
the wheels and surround the two lengths of chain. The gear case or chain cover
thus constituted is absolutely hermetic whilst it is at the same time detachable.
It is by no means fragile nor liable to injury upon experiencing the least shock
as is the case with the gear cases ordinarily in use.
The two chain wheel cases are closed by two covers which we prefer should be
of aluminium as in this case there need be no increase in the weight of the
machine as compared with the patterns at present in use.
Owing to its durability machines with this form of gear case are especially
suitable for touring purposes.
Thin 8th day of Danamber 1807
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.

page_text: Improvements in and relating to Driving Gear for Velocipedes, and
Gear Cases therefor.
We, CONSTANT ALPHONSE CHEVALIER and NORBERT GUSTAVE VASSEUR, both of
No. 6, Rue Singer, Caen (Departement du Calvados), in the Republic of France,
Mechanical Engineers, 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 improved hermetically closing detachable gear
case, combined with a crank in which all twisting action is avoided.
The characteristic feature of the pedal crank axle is that its chain wheel is
placed between the two ball bearings whereby a normal chain traction is obtained,
preventing all twisting action and increasing the rigidity of the machine.
The detachable gear case separately surrounds each length of the chain and is
connected with the crank bracket and loosely with the hub of the back wheel,
so as to constitute two cases hermetically closed around the wheel and the chain
pinion.
In the accompanying drawing:
Figure 1 is a horizontal section of the driving gear through the crank axle
and the back wheel axle.
Figure 2 is a front elevation and
Figure 3 is a section through one sheath of the gear case on line 1-2 of
Figure 2.
Figure 4 is an elevation of a chain cover or sheath showing the sliding door
applied thereto and
Figure 5 is a plan partly in section of Figure 4.
The crank axle a, to the ends of which the cranks bare keyed, is provided
with arms a a' in its central part, on which a toothed disc c, forming the chain
wheel, is fixed.
The ball bearings dare placed one upon each side of the chain wheel.
The fixed part or crank bracket is composed of the crank box or casing,
proper, e, of steel plate presenting a wide chamber or recess for completely
enclosing the chain wheel, and of a cover f stamped out of steel plate or prefer-
ably aluminium, which closes the box or casing e and is fixed thereon by means
of screws f. This cover supports in its centre the cup of the ball bearing d;
upon the periphery of the hox or casing four tubular sockets are provided,
on which the arms g g of the horizontal fork and the tubes h h of the frame are
supported. This box or casing e is moreover provided with two openings admit-
ting of the pessage of the chain k, and against these openings two chain covering
sheaths of sheet iron, tin plate or aluminium are united which protect the
chain and simultaneously serve to exclude any dust particles from the box or
casing e.
The chain wheel m is keyed in the ordinary manner upon the hub of the
driving wheel the same is enclosed in a box or casing of beaten out steel
plate which is brazed by means of appropriate tubular sockets to the tubes of
the frame, and carries an enclosing cover, arranged at the back. Two annular
plates adapted to surround the hub of the wheel and furnished with a
leather washer producing a hermetic joint upon the said hub, receive between
them the inner wall of the box n and of its cover n³, so as to prevent any dust
from entering at this side. The outer face of the box n is slotted in such a
manner as to permit of the displacements of the wheel axle y, when regulating

page_text: the tension of the chain, this slot is, however, closed by a cross piece r, mounted
on the axle q.
Tho chain covers are formed either of light metal, or of celluloid or the
like, of appropriate cross-section and longitudinal form for permitting the chain
full liberty of movement, regard being had to its being more or less in tension.
These covers are adapted to hermetically close the apertures formed for this
purpose in the boxes e and n of the crank axle and hub of the hind wheel
respectively.
Each of the chain covers 7 is provided with a longitudinal aperture (Figures 3, 4
and 5) the two edges of which are provided with slides adapted to receive the
grooved edges of a sliding doors formed of a flexible blade, the length of which
is somewhat greater than that of the opening. This door is placed in position
in an extremely simple manner by engaging one of its extremities in the
entrance to the slides and causing it to slide by means of knobs fixed upon
the sliding part to the opposite extremity of the said slide. The position of the
entrance of the slide upon the slightly curved portion in which the cover termi-
nates serves to impart to the sliding doors a certain elastic deformation when
it is engaged therein in such a manner that the pressure exerted by this sliding
part against the edges of the slides prevents it from becoming displaced when
once placed in position. Owing to the length of the part s, its two extremities
are applied upon the wall of the cover and thus hermetically close the opening
in the same. This closing device for the covers permits of readily obtaining
access to the chains for cleaning purposes without dismounting the parts; it
may be arranged upon one of the internal faces of one cover and upon the
external face of the other so as to enable both sides of the chain to be inspected,
or it may be arranged upon either the internal or the external face of both covers.
The gear case thus formed is hermetically closed, although it is capable of
being dismounted. It is not fragile and will not be damaged upon the least
shock as is the case with gear-cases as hitherto constructed. Finally it is of
small weight and can be easily kept in order.
Having now particularly described and ascertained the nature of our said in-
vention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. A gear case for safety bicycles, essentially comprising two sheaths of sheet
iron, tin plate or aluminium, for receiving the two lengths of the chain, with
slide doors for putting in place and removing the said sheuths and for inspecting
the chain, without the latter being touched; in combination with a crank box
of beaten steel plate, connected to the frame and provided with a wide chamber
or recess which encloses the chain wheel, receives upon its periphery the ends
of the sheaths and is closed by a cover of steel plate or of aluminium, supporting
ut the centre one of the bearings of the crank axle; and in further combination
with a box surrounding the driving chain wheel fixed to the frame, receiving
the rear ends of the sheaths of the gear case and provided with slide doors
adapted to embrace the hub of the wheel the whole mechanism being detachable
and closing hermetically.
2. In combination with a gear case of the kind described in the first claim,
a crank or peded mechanism essentially comprising an axle carrying cranks at
its ends and a chain wheel keyed between two ball bearings, one of said bearings
being supported by the cover which closes the chamber of the crank box, and the
other bearing being arranged at the opposite end of the said box.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.