IMPROVEMENTS IN VELOCIPEDES
Year: 1885

page_text: I, JOHN ALFRED GRIFFITHS of Priory Mill Coventry Engineer do hereby
declare the nature of my invention for "IMPROVEMENTS IN VELOCIPEDES" to be
as follows:-
This Invention is for the purpose of correcting the weakness found in many
velocipedes frames more particularly of the dwarf bicycles generally called
"Safeties" at the place where the forks of the front or large wheel are prolonged
downwards to carry the independent driving mechanism at either side.
Owing to the violent twisting and bending stresses to which these parts are
subjected they require very stiff supports.
This I accomplish without undue increase in weight by continuing the forks
downwards past the driving mechanism and joining the two sides together either
in front of the large wheel or preferably between the large and small wheels so as
to form a continuous loop round the half or lesser portion of the large wheel. This
loop will be quite clear of the ground at the lower end and may be formed of any
section or combination of tubes bars or suitable pieces and may be formed straight
or bent into any suitable shape to afford attachment to the bearings and other
accessories. The loop may be formed of one piece of bent tube or rod, fixed at the
same head or may be formed of several parts of tube, rod, pieces or connections
suitably attached to the head and to each other by brazing or other proper
fastening.
This loop frame will prevent the convenient use of many of the usual devices for
tightening the chain or adjusting the foot levers or other gear and I therefore
arrange such parts instead of sliding on the free end or other part of the fork to
slide in a slot in a bracket or lug attached to the fork and to prevent it slipping
have one or more screws to move the sliding part and fix it in place. Thus the
ends of the main axle of a "safety" may slide in a nearly vertical slot and be
raised to tighten the chain by a screw underneath lying in the slot. This device
may also be used to adjust other parts of velocipedes.

page_text: I JOHN ALFRED GRIFFITHS of Priory Mill, Coventry, 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 following
statement:
The drawing shows a complete machine of the front driving type with indepen-
dent cranks and separate gearing chains one at each side-usually termed the
Kangaroo" type.
"
The front frame which carries the driving wheel is pivotted to the back bone by
the usual Stanley head A or equivalent device. The frame is formed of two curved
steel tubes or forks one at each side of the wheel to which are attached the arms B
and the crank bracket C whilst the lower ends are preferably joined at D by a
short hollow U-tube which may be conveniently made of a hollow malleable
casting. In addition to this junction of the side tubes or forks by the U-tube at D
which is a permanent connection there is also a central removable connection
formed by the driving wheel axle which is securely bolted at each end to the
arms B. Thus the lateral parts of the frame to which the brackets C holding the
crank axles are attached is very rigidly supported enabling the rider to apply great
power to the pedals without causing additional friction of the driving gear from
the distation of the frame and consequent want of parallelism of the axles under
the severe driving stresses. Also any slight accident will not deform the frame
although its hollow construction reduces its weight below the average for this class
of machine.
In applying the same invention to bicycles with lever mechanism (such as the
"Facile" type) the lateral tubes may be curved the reverse way to that shown in
the drawing and joined by a U tube in front of the driving wheel. The fulcrum
pins of the lever gear may then be attached if desired very much farther forward
than is possible with the unjoined or open fork usually employed and longer levers
with straighter or more nearly vertical pedal paths may be used.
The inventor is aware that many bicycles such as the American Star Bicycle;
the Humber Safety, and the like have had the side tubes of the main frame joined
at more than one point.
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 use of a closed loop frame for that wheel of a bicycle which is pivotted for
steering the said frame also carrying the driving gear attached to that portion of
the loop which hangs beyond the axle of the driving wheel substantially as
specified.
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