Improvements in Driving Gear, Chiefly Designed for Use in connection with Velocipedes.
Year: 1899

page_text: Date of Application, 11th Apr., 1899-Accepted, 13th May, 1899
COMPLETE SPECIFICATION.
Improvements in Driving Gear, Chiefly Designed for Use in connection
with Velocipedes.
We, CHARLES P'ITMAN CRUTCHFIELD, Machinist, and JAMES INNES PITMAN,
Clerk, both of No. 1812, North Thirteenth Street, Philadelphia, Pennsylvania,
United States of America, 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:-
Our invention has special relation to bicycles employing a train of gearing for
the driving mechanism, and consists in the construction hereinafter particularly
described and claimed of mechanism for supporting and adjusting the inter-
mediate gear in the train of gearing.
Our invention has for its main object to provide a ready and most efficient
means of journalling the gearing in bicycles of the construction referred to and
of assembling and dissembling the same; a further object of our invention is
to provide an efficient and easily adjusted locking construction for the bearing
of the central gearing so that the same may be held, when in position, in perfect
adjustment with the other gear wheels, without liability to displacement.
In the accompanying drawings:-
Fig. 1 is a side elevation of a train of gearing of two gear wheels and a pinion
adjusted and in mesh with each other, adapted to a bicycle embodying our
improved construction.
Fig. 2 is a sectional view of the same on the line x-x, Fig. 1, but in a locked
position, representing in addition the relative position of the rear wheel of the
bicycle.
Fig. 3 is a perspective view of a portion of the gear supporting rod showing the
locking tongue and bearing support in detail.
A represents the centre gear wheel; B the gear provided on the crank shaft
and C the gear, or pinion, attached to the hub of the rear driving wheel; a
section of the crank, b, is illustrated in Fig. 2, which drives the gear B, which in
turn communicates the power to the rear driving wheel, E, through the medium
of the intervening gear, A, and pinion, C. In the drawings we have illustrated
the gear, B, and the pinion, C, as having anti-frictional roller teeth comprising
the transversely disposed pins, b¹, set in a groove formed by the circular
plates, c, cl, bolted together on opposite sides of the groove, the bolts, 61, having
This construction, how-
provided thereon the rotatable anti-friction sleeve, b³
ever, is merely a preferable construction of gear wheel and pinion into which
the toothed gear wheel, A, is adapted to mesh, though other constructions of
gear wheel may be readily employed.

page_text: The bearing of the centre gear wheel, A, is composed of a disk, A', preferably
equal to about one-third the diameter of the gear wheel, and of a thickness
slightly greater than the thickness of the gear wheel. The disk, A¹, has a
central hore, a, of a diameter slightly greater than the thickness of the rod, F,
which is adapted to pass therethrough, as hereinafter described; a slot, a¹, is
also provided in the said disk, A¹, opening into, and to one side of, the orifice, a,
adapted for the reception of the tongue, f, rigidly provided upon the bar, F,
to receive the said tongue in the assembling of the device. We preferably
provide a screw thread upon the circumference of the disk, A', and form the ball
bearing groove on the disk, A¹, as a journal bearing for the gear wheel, A. The
ball bearing groove proper we preferably construct of the two disks, d¹, d, each
being cut or formed with partially grooved or angular faces which when in
position opposite each other, as illustrated in Fig. 2, form the inner groove or
ball-race for the balls, g, the said disks, d', d, being internally screw-threaded
and adapted to the screw-threads provided upon the disk, A', and in this manner
by the adjustment of the respective disks, d, d, upon the disk, A', the size and
depth of this groove or ball-race may be regulated to a nicety. Upon the outside
of the sectional disks, and, we also provide locking disks, d and ³, similar in
construction. The outer member, d, of the groove or race-way is formed in the
inner circumference of the gear wheel, A, for the reception of the balls, b.
The horizontally disposed rod, F, is supported at its forward end to the crank
hanger bracket, and at its rear end upon the rear wheel axle, or tie rod, C',
being preferably adjusted upon the end of the said axle, or rod, C¹, in a slot, fi¹,
so that the parts may be easily adjusted. The rod, F, is preferably integral,
and bent or formed to constitute substantially parallel members, F1, F2, and the
member, F, transversely disposed at a point about midway of the rod or at
the point of bearing of the gear wheel, A, the member, F, by reason of the
construction of gearing being usually necessarily slightly longer than the
member, F. The inner faces of the member, F1 and F2, at the point of bearing
of the disk, A¹, are separated from each other at a distance equal to the thickness
of the disk, A¹, so that the rear portion of the outer face of the disk, A', will
bear against the inner face of the member, F1, and the inner face of the forward
portion of the disk, A', will bear against the inner face of the member, Fº.
The tongue, f, is preferably slightly narrower in width than the main body of
the bar, as illustrated in the drawing, and is extended forward as a continuation
of the member, F1, a slight distance, the distance between the rear face of the
member, F3, which is convexed, and the forward face of the tongue, f, being
equal to the diameter of the orifice, a, in the disk, A, the two said faces when
the disk, A', is turned to its locked position as illustrated in Fig. 2, forming
solid shoulders or walls upon which the walls of the orifice, a, neatly fit and
rest. When in the locked position, illustrated in Fig. 2, the set screw, n, is
provided through the disk, A¹, into the arm, F, in order to more securely hold
the disk in position. It will thus be seen that the disk, A¹, is rigidly secured
upon the horizontal bar, and forms a positive, substantial bearing for the gear
wheel, A.
From the foregoing description the operation and adjustment will be readily
understood.
In assembling, the gear wheel, A, is first properly adjusted on its ball bearings
on the disk, A, as hereinbefore described; the gear wheel, B, and the pinion, C,
being in position, the member, F1, of the rod, F, its rear end being freed from
the axle, C, which is slightly drawn back,-is inserted through the orifice, a,
in the disk, A¹, and the said disk advanced on the member, F1, until the slot, a',
registers with the tongue, f, when the disk, A¹, and the gear, A, being forced
back to the parallel line indicated in Fig. 2 are then slightly advanced to properly
mesh with the gear, B, to the position illustrated in Figs. 1 and 2; the disk, Ai,
is then rotated until the slot, a', assumes the position illustrated in the dotted
lines in Fig. 1; the screw, », is then adjusted and the disk rigidly locked upon

page_text: the supporting bar; the pinion, C, on the hub of the wheel, E, is then moved
forward until it meshes properly in the gear, A, and the axle, or tie rod, C¹, is
securely locked through the medium of the nut, f, in the slot, f', of the
member, F. In a similar manner the gearing may be readily taken apart for
cleaning, repair, or otherwise, with but little loss of time.
It is clear from the description of our improved construction that a most rigid
and substantial gearing support for bicycles employing this class of gearing is
most effectually provided, and that the gearing may be assembled, or dis-
assembled, most readily by any bicycle rider with little, or no knowledge of
mechanical constructions.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. In a train of gears, a removable gear-mounting or bearing comprising a
centre disk having a centrally disposed orifice provided therethrough and an
eccentrically located slot therein communicating with said orifice, a horizonally
disposed rod or support for said disk having a transversely disposed axle or
bearing adapted to said central orifice of said disk, a portion of said axle, or
bearing, being reduced to form a tongue adapted to said eccentrically located
slot in said disk on assembling or disassembling, substantially as described.
a
2. In a train of gears a removable gear-mounting or bearing comprising
centrally located disk, A', having transversely disposed orifice, a, and slot, a',
a supporting bar, F, comprising members, F1, F2, F3, and tongue, f, provided upon
said member, 13, said member, F, and tongue, f, being of a combined width,
or diameter longitudinally considered, substantially equal to the interior diameter
of the orifice, a, and adapted to impinge upon the walls thereof when in a locked
position, said tongue, f, being adapted to the slot, a¹, in the disk, A', in assembling
or disassembling, substantially as described.
3. In a train of gears, for bicycles, etc. a removable gear-mounting, or
bearing, A', having a ball-bearing groove or race-way provided upon the circum-
ference thereof, gear wheel, A, mounted thereon having a coincident groove in
its inner periphery at the point of bearing and balls provided in said grooves,
a transversely disposed orifice, a, centrally provided in said disk, A', and slot, a¹,
opening therein, a supporting bar, F, comprising members, F, F, F, and
tongue, f, provided upon said member, F3, said member, F, and tongue f, forming
the axis of the disk, A', of a diameter in one direction substantially equal to
the diameter of the orifice, #, and adapted when locked to impinge thereon,
said tongue, f, being adapted to the slot, a¹, in assembling or disassembling the
parts, substantially as described.
4. In a train of gearing for bicycles, etc., a gear support comprising a bar, F,
having members, F, F2, substantially parallel with each other, and transversely
disposed axis, F3, reduced in breadth forming a tongue, f, a disk, A, carrying
a gear wheel, A, in ball bearings on the circumference of the said disk in a
groove or raceway, said disk, A', having transversely disposed orifice, a, elon-
gated slot, a, opening therein said orifice, a adapted for the passage of the
axis, F, and slot adapted to the tongue, f, in assembling or disassembling,
substantially as described.
5. In a bicycle gearing, a gear wheel, A, central removable disk, A', screw-
threaded disks, d, d², provided in screw-threads upon said disk, A', forming a
groove or race-way, balls, g, groove, d, provided in said gear wheel, A, for the
balls, g, locking nuts or disks, dd, orifice, a provided in said disk, A¹, slot, a¹,
opening therein, supporting bar, F, having members, F1, F2, substantially
parallel with each other and transversely disposed axis, 13, reduced in breadth
forming a tongue, f, said axis adapted to the orifice, a, and tongue, f, to the

page_text: slot, a', in assembling or disassembling, and set screw, n, for rigidly securing
the disk, A', in position when locked, substantially as described.
Note this 11th low of Al 1900
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicants.