Improvements in Wheels for Bicycles and other Vehicles.
Year: 1893

page_text: Date of Application, 20th Dec., 1893-Accepted, 20th Jan., 1894
COMPLETE SPECIFICATION.
Improvements in Wheels for Bicycles and other Vehicles.
A communication from abroad by THOMAS GREENLAW PRINGLE, of Nos. 401
and 403, Oakland Street, Brooklyn, in the State of New York, United States
of America, Machinist.
I, JOHN CLAYTON MEWBURN, of 55 and 56 Chancery Lane, in the County of
London, Chartered Patent 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 :-
This invention relates to improvements in suspension wheels for bicycles and
analogous vehicles as tricycles and quadricycles.
I have shown the preferred form of this invention in the accompanying drawings,
wherein
Fig. 1 is a side elevation on a small scale of a safety bicycle constructed
according to this invention;
Fig. 2 is a fragmentary side elevation of one of the suspension wheels ;
Fig. 3 is a diametrical section thereof;
Fig. 4 is a similar section of the hub of the rear wheel;
Fig. 5 is a diagrammatic fragmentary view illustrating the manner of connecting
the spokes of the suspension wheels ;
Fig. 6 is an enlarged fragmentary cross-section through the grooved hub and
looped spokes of the wheel.
Referring to Fig 1, it will be seen that in general construction this improved
bicycle is very similar to the safety bicycles now commonly made. In the
construction shown it has a diamond frame A constructed of bars a b c and d, a
fork e extending to the rear wheel bearings, and brace rods fextending from these
bearings to the junction of the rods &c. The saddle may be mounted on this
diamond frame in any suitable way known in the art. A front bar B, the lower
end of which is forked to embrace the front wheel, passes through the tubular
bar a of the frame, and to its upper end the handle bars C C are attached. At the
junction of the bars dc and fork bars e, is formed the tubular housing g of the
crank-shaft D, on the ends of which are fixed the cranks E E. The rear wheel is
driven by a chain, passing over sprocket wheels on the rear wheel hub and on the
crank shaft respectively.
I will now describe the construction of the wheels W W. These, as is usual
in bicycle construction, are suspension wheels with wire spokes, and both are
alike in all essential respects. It is preferred, however, to provide the rear
wheel with a greater number of spokes than is necessary for the front wheel,
having adopted 36 for the front and 40 for the rear wheel, although other numbers
may be substituted. The wheels may also vary in diameter and proportions.
In the drawing I have shown pneumatic tires, but any other kind of tire may be
substituted. have shown the rims has being formed of metal plate rolled into
outwardly concave or channel form to properly embrace and hold the tire,
and the rim may be constructed of any of the well known shapes or propor-
tions. The wheel consists of the tire, the rim h, the wire spokes i i, and the hub j.

page_text: The hub is constructed of a single tube, being of smaller diameter than has been
customary at the point of engagement with the spokes, and of larger diameter
than has been customary in the neck or middle portion between the spokes. The
spokes are constructed with their middle portions looped or doubled to pass
around the hub, and the hub is constructed with parallel grooves in which the
looped portions of the spokes may rest, and whereby they are held in proper
positions where they engage the hub. Each spoke or pair of spokes consists of a
single length of wire bent or looped at its middle portion in a curve conforming to
the diameter of the hub, and having its ends screw-threaded or otherwise con-
structed for adjustable attachment to the rim. The construction of the hub is
best shown in Fig. 4. It is mude of a tube of steel or other metal of a suitable
diameter (or a tubular casting), which near the opposite ends is formed with
concentric grooves for receiving the looped portions of the spokes. These grooved
portions are lettered jj. Each portion has as many grooves as the total number
of spokes in the wheel divided by four. The hub may be of uniform diameter
from end to end, and by preference it is somewhat enlarged conically at the
portions, so that the inner grooves, that is, those toward the middle of the
hub, have a greater circumference than the outer ones. This is done in order
that there need be no difference in the length of wire cut for the spokes, all the
spokes being of the same length, notwithstanding that they extend from the rim
to grooves at different distances from the middle of the hub, the outer spokes
extending the greatest distance from the middle, being carried around in the
grooves of smallest circumference, and the degree of coning being such that the
successive grooves toward the middle are enough larger in circumference to
compensate for the less distance between the points of attachment of the spoke at
the rim and its points of engagement with the grooves in the hub. The bent
portions of the spokes need not be bent to the exact curve of the grooves, since
when the strain is put on the spokes by screwing up their ends, their bent portions
will adapt themselves to the exact shape of the grooves, and be drawn down into
the grooves so as to have a strong and intimate frictional engagement therewith.
The frictional engagement thus attained is so effective that when the wheel is put
under proper tension by the tightening up of the spokes, it is impossible to
turn the hub independently of the wheel by any strain that could be applied to it
in the act of driving the bicycle. To secure the most effective adhesion between
the spokes and hub, the grooves in the hub are made with tapering sides, as shown
in Fig. 6, so that as the spokes are tightened they are drawn down into the
grooves and caused to fit very tightly there-against. The grooves may be thus
either V-grooves, or preferably round-bottomed grooves with their bottoms of a
diameter less than that of the wire constituting the spokes, so that as the spokes
are drawn down the wire is compressed as it sinks into the bottom portion of the
grooves.
In Fig. 2 the spokes on the near side of the wheel are shown in full lines, and
those on the far or remote side are shown in dotted lines. In putting the wheel
together, I will suppose the first pair of spokes marked 1-1 to be applied (for
instance) to the outside groove. The next pair marked 2-2 is then applied in the
second groove, the third pair marked 3-3 applied in the third groove, and so on, until
the last pair 9-9 is reached, this being put into the last or inner groove. In order
to most thoroughly and effectively brace the wheel the spokes are interlaced.
This is done by carrying the first spoke of pair 2 over the second spoke of pair 1 at
their point of intersection marked ; the first spoke of pair 3 over the last spoke
of pair 2; and so on around the wheel. Thus each pair of spokes is interlaced
with its two adjoining neighbours all around the wheel at their crossing points
denoted at ær, with the exception of the first and last, spokes of pairs I and 9,
which do not come into contact with each other, being spaced so far apart that it
would be impracticable or undesirable to connect them. The interlacing is best
shown in Fig. 5, which is drawn out of proportion in order to clearly show that
spoke 2 passes over spoke 1 at a and then under it at y where it enters the second

page_text: groove, and returning passes under spoke 3 at r, so that this spoke 2 is deflected
outwardly at one point and inwardly at the other, bearing at the points against
the spokes 1 and 3 and being braced and supported thereby. This construction
renders the wheel very stiff and affords great resistance against any buckling
strains.
The novel construction of the hub j is characterized by its being of approximately
the same diameter from end to end, instead of being as has heretofore been usual,
expanded into two disks at the points of attachment of the spokos, and contracted
into a small tubular neck barely larger than the axle between these disks. The
enlarged neck imparts great stiffness to the hub, giving it great resistance against
torsional and longitudinally compressive strains. This construction also renders
the hub of lighter weight for a given strength, since it is made integrally from end
to end. The rear or driving wheel hub is made with its end portion beyond the
grooved portion, screwthreaded or otherwise strongly united to the sprocket-
wheel k¹, the hub being preferably formed with an external collar at against
which the sprocket-wheel is seated. The hubs of both wheels are formed with
internal collars or shoulders near the opposite ends, against which are seated the
grooved rings of the ball bearings. These rings are made a tight fit with the
ends of the hubs and pressed in tightly against the shoulders j. They are made in
a separate piece from the hub in order to conveniently afford a greater thickness
for resisting the thrust of the balls; to admit of more readily constructing them
with hardened faces against which the balls may roll; to facilitate the grinding
and finishing of the surfaces; and to permit of their ready replacement in case they
should become cracked or broken. The ball bearings are otherwise of the usual
construction having a series of balls rolling around an adjustable cone, or any other
suitable arrangement known in the art in ball bearings.
This invention is not necessarily limited to the precise details of construction
hereinbefore described, but may be modified considerably in structural respects
without departing from its essential features. Those features which are considered
essential to the invention are hereinafter defined in the claims.
Having now particularly described and ascertained the nature of the said inven-
tion as communicated to me and in what manner the same is to be performed, I
declare that what I claim in respect of suspension wheels for bicycles or other
vehicles having their hubs formed with a plurality of parallel grooves near their
opposite ends & their spokes formed of doubled wire with their ends secured to
the rim and their looped portions embracing the hub and lying in the said grooves
substantially as herein explained, is :—
1. The arrangement of the successive spokes to interengage or interlace with one
another at their crossing points, in substantially the manner described.
2. The construction of the hub with its grooved portions made conical or
tapering, to enable the spokes to be made of uniform length, in substantially the
manner set forth.
3. The construction of the hub as a metal tube with circumferential grooves near
its opposite ends to receive the looped spokes, and with its middle portion of a
diameter nearly or quite as great as the said grooved portions, whereby its stiffness
is increased.
:
Dated the 20th day of December 1893.