Improvements in or relating to Chain Wheels and Cranks of Cycles.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in or relating to Chain Wheels and Cranks of Cycles.
I, HARRY PARSONS, of Ferndale, Wren Street, Coventry, in the County of
Warwick, Works Manager, do hereby declare the nature of this invention to be
as follows -
The object of my invention is to effect improvements in the method of connect-
ing the chain wheels and cranks of cycles whereby the chain wheels may be
readily disconnected or others substituted, as for instance when an alteration of
the gear is desired, or for any other purpose.
According to my invention, I form the crank with a flanged boss on which the
chain wheel is mounted. The chain wheel is accurately fitted to the boss so as to
prevent any lateral movement thereon. The periphery of the boss is cut away at
two or more points to receive a tapered nut at each opening of the periphery,
the sides of which are also tapered. The chain wheel boss or sleeve is pierced with
two or more holes accurately corresponding with the slots in the periphery of
the crank boss, and through these holes screws or bolts pass and engage with the
tapered nuts. On screwing the bolts into the nuts the pressure of the tapered
edges of the nuts upon the corresponding tapered edges of the slots in the periphery
of the crank boss forces the periphery in an outward direction against the inner
surface of the chain wheel sleeve, thereby firmly securing the crank boss and
chain wheel together. Any tendency of the chain wheel to lateral movement is
prevented by the flange on the periphery of the crank boss and the flanges or pro-
jections on the tapered nuts which engage with the edges of the slot in the crank
boss.
Improvements in or relating to Chain Wheels and Cranks of Cycles.
I, HARRY PARSONS, of Ferndale, Wren Street, Coventry, in the County of
Warwick, Works Manager, 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 chain wheels and cranks of cycles,
and it has for its object the construction of those parts in such a manner that

page_text: the chain wheel may be easily and readily removed when it is desired to alter
the gear of the machine, or for any other purpose.
In carrying the invention into effect, I form the crank with a flanged boss turned
to fit the centre of the chain wheel, which is mounted upon and secured to the
said flanged boss by means of two or more wedge-shaped nuts engaging with the
edges of the flange, which is cut away to receive the nuts, the nuts being drawn
up into the openings by means of studs passing through the boss of the chain-
wheel and screwed into the nuts, thereby expanding the crank boss into the chain-
wheel and insuring the latter being mounted absolutely concentrically, which
would not be the case if there were no expansion.
And in order that this invention may be the better understood, I will proceed
to describe the same with reference to the accompanying drawings, in which:-
Fig. 1 is a front elevational view of one form of my invention;
Fig. 2 is a back view;
Fig. 3 is a side elevational view of the crank and flanged boss forming part of
same; and
Fig. 4 is a view showing the nuts or wedges for securing the wheel to the boss
upon the crank.
A is the crank, forming part of which is a vertical plate B provided with open-
ings B which allow of expansion of flange for a considerable length of its cir-
cumference, and having a horizontal flange C, in which are formed two open-
ings D, D¹, the edges of the flange where cut away being bevelled as shown.
A shoulder E, Fig. 3, is provided upon the flange to keep the chain wheel in
position when the same is in place. F is the chain wheel, the boss G of which
is bored to receive the flange C, and which has formed in it two diametrically
opposite holes, H, H', through which pass screws or studs I, I, the position of
the said holes being such that when the wheel is placed upon the crank boss the
holes shall come in the centre of the openings D, . J, Jare thin plates or nuts
somewhat wider than the openings D, D', and with tapered edges which engage
with the tapered sides of the openings in the flange C, and also provided
with parallel ears or lugs K projecting at the ends of the plates J, J¹ from the
sides, which lugs are adapted to engage with corresponding slots or openings
formed in the shoulder E (see Fig. 3), so that when the nuts are drawn up by
bolts I, I, the outer diameter of the flange C is expanded within the hub of the
wheel F, and the same is firmly held thereon, any lateral movement of the chain
wheel being prevented by the shoulder E upon the crank boss and the projections K
upon the taper nuts.
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;-.
.
In a crank for cycles the combination therewith of a flanged boss and suitably
shaped wedge pieces for expanding the diameter of the flange and securing the
chain wheel thereto as described and illustrated by the accompanying drawings.
Dated this Fifteenth day of June 1898.
WM. JORDAN,
Agent for the Applicant.