Improvements in Ball Bearings.
Year: 1897

page_text: Date of Application, 11th May, 1897-Accepted, 19th June, 1897
Improvements in Ball Bearings.
We, WILLIAM DIEBEL, Machinist, of the City of Philadelphia, and WILLIAM
FREDERICK REMPPIS Manufacturer, of the City of Reading, both in the State
of 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 relates to new and useful improvements in ball bearings for the
shaft and axles of bicycles or similar machines.
Heretofore it has been customary to provide the shafts or axles of bicycles with
a pair of bearings spaced as far apart longitudinally as conveniently may be, it
being considered necessary to support the shaft near each of its ends in order to
maintain it in horizontal position under the strains incident to the operation of the
machine. This principle of bearing construction renders it impossible to secure as
narrow a tread as is desirable on the crank shafts without bringing the two bearings
unduly close together. In order to attain this desired object we have in our
improved construction dispensed entirely with these bearings adjacent to the ends
of the shaft and employ instead a single bearing only, located about midway.
between the ends; and in order that this single bearing may serve the purpose of
maintaining the shaft in horizontal position under the strains in this instance
brought upon it through the crank secured to its opposite ends we form it of a large
diameter compared with the diameter of the shaft, so as to make the distance
between diametrically opposite bearing points on said bearing approximately equal
to the distance provided between the two end bearings as heretofore commonly
used, the shaft itself being of course made sufficiently rigid to prevent any yielding
in the portions extending beyond its central bearing. We have found in practice
that this improved construction not only enables us to narrow the tread to the
greatest practicable extent but that it also greatly reduces the friction and the
work required in fitting and adjusting, as compared with the ordinary construction
in which it is impracticable to insure absolute uniformity in the two end bearings
employed.
The accompanying drawing illustrates the application of our invention to the
crank shaft of a bicycle.
Fig. 1 is an elevation showing the crank hanger and bearing parts in section and
indicating in dotted lines the position of the sprocket wheel and cranks relative to
the bearing.
Fig. 2 is a cross-sectional view taken through the middle of the crank hanger or
casing.
Fig. 3 shows the spacing device or ring separately.
The hanger box or casing A forms part of the framework of the bicycle, the
tubes of which are united thereto by means of suitable projections a, a' and a².
The inner face of this circular casing is arranged to form an exterior bearing for
the central series of balls C, a separately formed grooved ring A* being preferably.
secured therein as indicated in the drawing to form such bearing.
D represents the crank shaft to which is secured as usual a sprocket or other
suitable driving gear H located at one side of the casing and cranks G G at
each end thereof. About midway of the length of the shaft is located the
inner bearing for the balls C. This inner bearing is formed in two parts E¹ E²
Price 8d7

page_text: as shown, one of which, E', is preferably immovable upon the shaft while the
other E is removable therefrom and adjustable thereon relatively to the fixed part
by means of an internally threaded hub which engages a screw threaded portion of
the shaft. The peripheries of both these parts are oppositely bevelled as shown so
as to form jointly a grooved inner bearing between which and the grooved outer
bearing A the balls C roll.
The diameter of this ball race, as already explained must be comparatively large
in order that a downward strain for instance upon one end of the shaft may not act
at an objectionable leverage upon the bearing surfaces, thereby increasing the
strains and wear and multiplying also any lost motion that may exist between the
bearing surfaces. If this diameter of our single bearing be made equal to
the spread of the two end bearings heretofore employed, and the overhanging parts
be rigid, then will the conditions as to leverage and lost motion be substantially the
same; with the decided advantage in favor of our improved construction however
that the spread of the cranks may be reduced, and that the necessity for providing
two uniform bearings for the same shaft is avoided.
In order to further improve our bearing we employ in connection therewith a
spacing plate or ring F which we locate between the fixed and adjustable parts E¹
and E of the inner bearing. This device has a central opening F to admit the
shalt and peripheral notches or recesses ff adapted to engage the balls and keep
them a uniform distance apart in their travel. A nut e 3 upon the shaft serves to
lock the movable part E2 of the inner bearing after it has been adjusted to its
proper position on the shaft. Cover plates el e¹ are provided to serve as dust guards
for the bearing.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is:
1. A shaft mounted in a hanger or support upon a single bearing which is
located midway of its length and is of relatively large diameter, substantially as
described.
2. The combination, in a bearing as herein described for bicycles and the like, of
a shaft, D,.a two-part inner bearing disc carried by said shaft with one of the parts
adjustable relatively to the other part, a grooved outer bearing ring and balls
interposed between said grooved outer bearing ring and the grooved periphery of
the two-part disc, substantially as described.
3. The combination, in a bearing as herein described for bicycles and the like,
of a shaft, D, a two-part inner bearing disc carried by said shaft with one of the
parts adjustable relatively to the outer part, a grooved outer bearing ring, balls
interposed between said grooved outer bearing and the grooved periphery of the
two-part disc, and a spacing device, interposed between the two parts of the disc
and having its periphery recessed or notched to engage the balls, substantially as
described.
Dated this 11th dox of May 1907
WHEATLEY & MACKENZIE,
4 Chancery Lane, London, W.C., Agents.
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