Improvements in or in connection with Velocipedes.
Year: 1896

page_text: Date of Application, 7th Feb., 1896-Accepted, 21st Mar., 1896
COMPLETE SPECIFICATION.
Improvements in or in connection with Velocipedes.
A communication by WILLIAM EDGAR PRALL, M.E., of Hotel Arno, Washington,
D.C., United States of America.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors 6, Lord Street, Liverpool and 6, Bank. Street
Manchester, both in the County of Lancaster 118, New Street, Birmingham in the
County of Warwick and 31 High Holborn in the County of Middlesex, Civil
Engineer, do hereby declare the nature of this invention and in what inanner the
same is to be performed, to be particularly described and ascertained in and by the
following statement :-
The invention relates to velocipedes, and has for its object to provide a back stop
or support for the rider adapted among other uses to receive the back thrust of his
limbs when driving the bicycle at great speed and also to adapt such a support for
use in braking or back pedaling; and the invention consists in the construction
bereinafter described and particularly pointed out.
Figure 1 is a side elevation of a bicycle seat and back stop; and
Figure 2 is a similar view of another form.
Numeral indicates the seat post of a bicycle and 2 the seat. As shown, the
seat is supported from a ring or clamp 3 embracing and fastened to a bar or arm 4
rigidly connected to the seat post.
5 indicates a set screw for securing the seat ring 3 to arm 4, and 6 a set screw
for securing the seat post in the tubular member 7 of the frame. These parts may
be of any approved form.
Upon the backward extension 4* of a seat supporting arm 4 is rotatably held an
arm or curved post 8 held in a socket of a hub 9, said hub fitting the bar
extension 4 and rotatable thereon. 11 is a clutch ring fastened by a set screw or
the like to the bar extension and provided with a bevelled lug or lugs 12 adapted
to engage suitably shaped recesses in the hub 9.
14 indicates a washer and 15 a coiled spring surrounding the bar extension 4*,
the spring normally holding the hub engaged with the clutch ring 11.
16 denotes a stop or support of suitable form to fit the back of the rider.
may be held in a socket in the top of the hub by a set screw 17.
It
In Figure 2 the back stop is shown supported more directly to the seat and
provided with a spring held friction block 18 for which however a friction clutch
may be substituted. The particular means for supporting the stop and the point
of its attachment to the machine is not of the gist of the invention.
The back stop or support 16 has such form and situation that it overhangs the
seat and is adapted to be firmly held in direct opposition to the thrust of the rider's
limbs upon the pedals of the machine.
In prior machines when they are driven at a high speed the weight of the rider
is insufficient to resist the re-action of this thrust and his body is lifted from the
seat. This improved stop or support acting upon the lower part of the back of
the rider in a direction opposite to the thrust of his limbs enables him to more
fully expend his strength upon the pedals instead of wasting a portion of it in
lifting his weight from the seat.
The back stop is made movable, as by swinging in a vertical plane about the bar
extension 4, in order that it may be moved out of the rider's way when he mounts
the seat or dismounts. This can be effected by compressing the spring 15 and

page_text: unclutching the hub at the foot of the stop whereupon it can be turned sidewise to
a position indicated in dotted lines.
The details of construction may be varied by mechanical skill. It is not
essential that the back stop be supported directly by the seat post, nor that the back
stop be adapted to be moved from over the seat by swinging laterally with respect
to the seat.
The leverage of the knee joint when the limbs are nearly straightened is very
great and far exceeds that required to lift the body. This improvement mainly
consists in the construction whereby the rider is enabled to apply to the pedals
more force than is possible without a counteracting device to limit this body-lifting
effect of his limbs. This is especially true in case the body of the rider is inclined
greatly forward and much of his weight thrown upon the handle bars. In such a
position a boy or man of light weight can, by the use of the present invention,
easily exert double the force on the pedals possible in the prior construction in which
the only re-acting force is his own weight on the seat. The objects of this invention
cannot be secured by flexible or other supports for the loins, but a fixed stop
adjacent the sacral regions is essential. The invention is specially useful in
overcoming steep grades, braking or speeding.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, as communicated to
me by my foreign correspondent, I declare that what I claim is:
1. In a bicycle or the-like, the combination of a seat and a fixed stop adapted
to bear upon the sacral regions of the back in opposition to the downward thrust
of the rider's leg when exerting its most effective force, substantially as described.
2. In a bicycle or the like, the combination of a seat, a back stop or support,
and a friction clutch, the stop being adapted to hold the rider in his seat and to be
automatically swung out of the way by the rider in the act of dismounting,
substantially as described.
Dated this 6th day of February. 1896.