Improved Construction of Cranks for Bicycles and other Velocipedes.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improved Construction of Cranks for Bicycles and other Velocipedes.
I, JAMES TURNBULL, Engineer, of 14, Plumstead Road, Plumstead, Kent, do
hereby declare the nature of this invention to be as follows:-
The end of the crank fitting on the axle may be made the same as that of any
ordinary crank, or of any specially made crank, which is constructed to suit the
fittings of the machine the crank is to be used upon. The crank end thus
described is fitted and brazed, welded or otherwise securely fixed into a tube
which may be round, oval, square or any other convenient shape, a weldless steel
tube is preferred but it may a tube of any other suitable metal or material.
Into the other end of the tube thus described is fitted and brazed, welded, or
otherwise securely fixed, a solid piece of metal, which with the exception herein-
after mentioned, fills the pedal end of the tube, for a convenient distance below
the pedal.
A hole is drilled and tapped through the tubular crank and through the solid
piece just now described, to receive the pedal pin which is screwed to fit.
The solid piece before being finally fixed in the tube having had a piece cut
out of it, so as to leave a vacant space between the inner surface of the tube-on
the pedal side-and the solid piece fitted into it.
The intention is, that when the pedal pin is screwed up hard against the side
of the tubular crank, the side of the crank will give inwards slightly thus tighten-
ing and locking the threads of the screwed parts on each other.
If the face of the crank against which the pedal pin abuts be round or of any
other unsuitable shape to fit properly on the surface of the shoulder of the pedal
pin a washer, fixed or loose may be inserted to fill up the space.
Dated this 10th day of December 1898.
Improved Construction of Cranks for Bicycles and other Velocipedes.
I, JAMES TURNBULL, of 14, Plumstead Road, Plumstead, Kent, Cycle Engineer,
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 follow-
ing statement:-
The end of the crank which fits on the crank shaft or axle is made the same
as that of any ordinary crank, or of any specially made crank which is construc-
ted to suit the fittings of the machine the crank is to be used upon.

page_text: The crank end thus described is fitted & welded, brazed or otherwise securely
fixed into one end of a tube which may be oval, round or any other convenient
shape. A weldless steel tube is preferred, but it may be made of any other metal
or suitable material.
Into the other end of the tube is fitted and brazed, welded, or otherwise securely
fixed a solid piece of metal, which with the exception hereinafter mentioned fills
the pedal end of the tube for a convenient distance below the pedal. A hole is
drilled and tapped through the solid piece just now described, and through the
tube enclosing it to receive the pedal pin which is screwed to fit into it.
The solid piece before being finally fixed in the end of the tube has a piece
cut out of it, so as to leave a vacant space on the pedal side-between the
interior of the tube and the solid piece fitted into it.
The intention is that when the pedal pin is screwed up hard against the tubular
crank the side of the crank will give inwards slightly thus tightening and lock-
ing the threads on each other. As an alternative method the pedal end may be]
made solid and the necessary space machined out.
If the face of the crank against which the pedal pin abuts be round, or of any
other unsuitable shape to fit properly on the shoulder of the pedal pin, a washer
fixed or loose may be interposed to fill up the space.
Fig. 1 shows front view of crank.
Fig. 2 shows side view of crank also section of the pedal end of crank.
Fig. 3 is the boss, or axle end of crank before being fixed into the tube.
Figs. 5, 6 & 7 are two views and a section of the solid piece as fitted into the
end of the crank, the part cut out making the vacant space--as shown in Fig. 2
between the two portions of thread or screw.
Fig. 4 is section of tubular portion of crank which in this instance is oval,
Fig. 8 is side view of washer, which is also shown in Fig. 2 fixed on the crank
although it is shown to be screwed conjointly with crank, it need not be so if
more convenient otherwise.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
The improvements in the construction of cranks for bicycles and other
velocipedes as herein before described and illustrated in the accompanying draw-
ings, the said improvements consisting of a tubular crank with solid ends, the
pedal end of which encloses a vacant space which divides the thread of the hole
in which the pedal pin is fixed into two parts.
T
1000