Improvements in Crank-shafts and Bearings, chiefly Designed for Velocipedes.
Year: 1897

page_text: Date of Application, 28th Sept., 1897-Accepted, 12th Mar., 1898
COMPLETE SPECIFICATION.
Improvements in Crank-shafts and Bearings, chiefly Designed for
Velocipedes.
I, WILLIAM WALLACE TUCKER, of No. 105, Huntington Street, in the City of
Hartford, in the County of Hartford, and State of Connecticut, United States
of America, Gentleman, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
The object of this invention is a crank-shaft and bearing therefor especially
adapted for use in connection with bicycles and other velocipedes, the main
feature of the invention being a crank-shaft made in two sections extending
entirely through a suitable bearing-sleeve, one of said sections having a tapering
bore and the other section being tapered to enter said bore and be held in place
therein by a wedging action for rotation in unison therewith.
Another important feature of the invention is a bearing for the crank-shaft in
which the balls that surround the shaft are seated in separated recesses in a
retaining-ring inclosing said balls, whereby rubbing of the balls against one
another is prevented, and hence the friction of the bearing is reduced and the life
of the balls prolonged.
In the drawings Figure 1 is a side elevation with parts broken away, of a
portion of the framework and crank mechanism of a bicycle embodying my inven-
tion. Fig. 2 is a transverse section of the same. Fig. 3 is a transverse section
of one of the removable bearing-cones with its ball-separating retaining-ring, and
a holding-ring for maintaining the balls and the retaining-ring in place. Fig. 4
is a side elevation of the retaining-ring. Fig. 5 is an end elevation, looking from
the right in Fig. 2, of the inner section of the crank-shaft and a portion of the
crank extending therefrom. Fig. 6 is a sectional detail illustrating the manner
of connecting the sections of the sprocket-wheel. Fig. 7 is a detail of a portion
of the crank-shaft, illustrating the construction for locating these parts circum-
ferentially relatively to each other and for permitting their separation. Fig. 8 is
a sectional detail of the hub of the sprocket-wheel. Fig. 9 is a side view of a
sleeve carrying the fixed cones of the bearing; and Fig. 10 is a transverse section
of the same.
My invention is illustrated herein in connection with the crank-shaft hanger C
of a bicycle, and the crank-shaft extends in the usual way entirely through the
bearing-sleeve formed by this crank-hanger. The crank-shaft illustrated com-
prises two shaft-sections A and B, the former of which is tubular and has a
tapering bore, while the latter is tapered externally and extends through the
tapering bore of the tubular shaft-section, so that when suitable pressure is
applied to these parts they will be wedged together for rotation in unison.
The two shaft-sections have, respectively, right-and-left-hand screw-threads at
one end of the crank-shaft, these screw-threads being designated by 15 and 12
and forming means for permitting the shaft-sections to be drawn together and
wedged in place. Any suitable coupling member correspondingly threaded may

page_text: be used to draw the shaft-sections together, but I prefer to employ for this
purpose a sprocket-wheels, the hub 17 of which has internal right-and-left-hand
threads of the same pitch as those of the shaft-sections A and B.
After the sections of the crank-shaft are wedged firmly in place by turning the
sprocket-wheel to the proper extent the latter should be secured in position by
some suitable fastening means-such, for instance, as that shown in Fig. 2.
The two cranks, which are designated by 13 and 14, are preferably formed integral
with the respective shaft-sections A and B, and the crank 13 has on its inner
side a tubular stud 18, internally and externally screw-threaded, while the
sprocket-wheel has a strengthening-web 20 in which is a series of perforations 22
equidistant from the centre of the wheel, suitable means being employed in
connection with any one of these perforations to secure the sprocket-wheel to the
tubular stud 18 of the crank 13. It will be noticed that any one of these perfora-
tions may be brought opposite said stud, when the two parts may be joined
together by a screw 23, which may be passed through such perforation and into
the stud. A check-nut 24 may be screwed on to the stud 18 to form a bearing-
surface for the outer side of the sprocket-wheel for all adjustments of the latter
toward or from the crank 13.
The shaft-section A preferably has a locking opening 21 at the end of its
tapered bore, and the shaft-section B has its sides flattened to form at its inner
end a locking member adapted to be received in the opening 21, to locate the two
members positively in circumferential direction. This construction also permits
the two sections to be separated readily by driving a pin into the opening 21 in
case the parts should become tightly wedged.
In Fig. 6 I have shown at 18¹ how the two main parts of the sprocket-wheel
may be connected by short screw-bolts, except where the connection is made with
the crank 13.
The bearings which surround the shaft at opposite ends thereof are designated,
respectively, by b and 61, and are substantially identical in construction. Each
has a movable bearing-section or cone 13*, having external screw-threads 131,
engaging corresponding internal threads 13" in the crank-hanger C. The bearing-
cones 13* also have recesses 13111 so as to permit the turning of said cones by a
spanner.
The fixed bearing-cones for the two bearings 6 and 64 are shown at 421 and are
formed on a sleeve 42, which at the outer end thereof is internally screw-threaded
to engage the external screw-threads 12 on the shaft-section A, to locate the sleeve
longitudinally of the shaft.
Referring, now, to Figs. 1 to 4, inclusive, the ball-separating retaining-rings
are designated by R, each being preferably in the form of a sheet-metal annulus.
Each ring has a central opening through which the shaft may pass, and a series
of recesses or sockets 43, having contracted openings with shoulders 44, which
prevent removal of the balls in the plane of the retaining-ring. These ball-
sockets are preferably somewhat elongated or slightly elliptical so as to permit the
balls to move freely and have slight play in the bearing.
The retaining-rings R are mounted loosely in annular seats in the bearing-
cones 13* and abut against the stop-shoulders 26, so that they may rotate with
the shaft without being displaced sidewise. Holding-rings 30, having external
threads 31, engaging internal threads 32 on the bearing-cones 13* and having
openings for the shaft are employed to prevent this sidewise movement of the
retaining-rings. The holding-rings also have recesses 35 to permit them to be
turned by a spanner.
In order to prevent entrance of dust through the openings in the bearing-cone,.
suitable dust-guards 36 may be seated in annular grooves 37 in said bearing-
cones.
It will be apparent that either bearing-cone may be removed from the shaft
and with it the holding-ring 30 and the balls 50, without dropping the latter, by
simply unscrewing said bearing-cone. Moreover, on the removal of either movable

page_text: bearing-cone with its retaining-ring and holding-ring, any ball may be taken out,
without disturbing the others, by simply unscrewing the holding-ring.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
1. The combination of a bearing-sleeve; a crank-shaft extending through and
rotatable in the bearing-sleeve and comprising two detachable sections, one of
which has a tapering bore and the other of which is tapered and extends into said
bore; and means for wedging the two sections of the crank-shaft together for
rotation in unison.
2. The combination of a bearing-sleeve; a crank-shaft extending through and
rotatable in the bearing-sleeve and comprising two detachable sections, one of
which has a tapering bore and the other of which is tapered and extends into said
bore, said sections having, respectively, right-and-left-hand screw-threads near
one end of the crank-shaft; cranks secured to said shaft-sections; a sprocket-
wheel having right-and-left-hand screw-threads for engaging the sections of the
shaft and wedging said sections together for rotation in unison; and fastening
means for the sprocket-wheel.
3. The combination of a bearing-sleeve; a crank-shaft extending through and
rotatable in the bearing-sleeve and comprising two detachable sections, one of
which has a tapering bore and the other of which is tapered and extends into said
bore, said sections having, respectively, right-and-left-hand screw-threads near one
end of the crank-shaft; cranks secured to said shaft-sections; a sprocket-wheel
having right-and-left-hand screw-threads for engaging the sections of the shaft
and wedging said sections together for rotation in unison; and fastening means
for securing the sprocket-wheel to one of the cranks at any desired point circum-
ferentially of the sprocket-wheel.
4. In a ball-bearing, the combination of a fixed and a movable bearing-cone,
and a ball-separating retaining-ring surrounding the balls and having ball-
sockets for separating the balls.
5. In a ball-bearing, the combination of a movable bearing-cone; a ball-
separating retaining-ring surrounding the balls and having ball-sockets for
separating the balls; and a holding-ring detachably secured to the cone, for
maintaining the retaining-ring and the balls in position in the cone.
רד
100K
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.