AN IMPROVED TREADLE APPARATUS
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Adolphus Clark at the Office
of the Commissioners of Patents, with his Petition, on the 15th
February 1875.-A communication from abroad by Gustavus Davis
Dows, of Boston, Massachusetts, United States of America.
I, ADOLPHUS CLARK, of 46, Frith Street, Soho Square, in the County
of Middlesex, Manufacturer, do hereby declare the nature of the said
Invention for "AN IMPROVED TREADLE APPARATUS," a communication, to
be as follows:-
My Invention relates to an improved treadle apparatus chiefly
designed for operating sewing machines, small turning lathes, and drilling
apparatus, and other light machinery usually operated by a treadle.
The use of the ordinary treadle for sewing machines is open to very
serious objections on the ground of its liability to cause injury to the
health of the operators of such machines through the improper and
unnatural muscular action resulting from the position of the feet and
the motion of the treadle, and this reason has occasioned its disuse to a
great extent by ladies, who prefer the inconvenient and comparatively
slow hand machines. But my improved treadle is free from such
objections; its action is induced with an almost imperceptible motion of

page_text: the foot, and without fatigue or improper or unhealthy action of any
of the joints or muscles of the leg; its operation can be maintained by
either foot separately, or by both feet acting together, and with a slow
and gentle action of the foot or feet a very rapid motion is given to the
machine, and moreover the said apparatus when in action can be stopped
immediately without inconvenient exertion.
The said improved apparatus consists essentially of a foot lever,
connected by a rod to a friction pawl, arranged to act upon a circular
flange or hoop attached to a toothed wheel, which is geared into a small
pinion on a fly wheel shaft, whereby motion is imparted by a pulley and
belt, or by other suitable means, to the sewing or other machine to
which the said apparatus is applied.
In applying my said Invention to a sewing machine or other machine
mounted upon a table or slab, I arrange between the two frames or
standards supporting the said table a rod or shaft which forms the
fulcrum of the foot levers. I prefer to use two of these foot levers, as it
is convenient in the use of the machine to be able to use either foot or
both feet as desired.
The said levers are preferably made of cast iron, and are of a con-
venient shape to receive the feet, the heel of each foot being just over
the fulcrum of the lever.
The said foot levers are provided with springs to keep them in a
raised position; the said springs are preferably coiled around the rod and
have one end projecting therefrom to about the middle of the levers.
These foot levers are connected by light rods of wrought iron or other
suitable material with the levers of the aforesaid pawls. These pawl
levers are fitted loosely upon the shaft or axis of the aforesaid toothed
wheel, and have a vibrating motion imparted to them by the said foot
levers when the latter are operated. The said shaft or axis is supported
to turn freely in brackets attached to the table or frame of the machine.
The pawls are pieces of iron or other suitable metal hinged or jointed to
the said pawl levers and formed with a notch in one side, into and
through which the aforesaid circular flange or hoop projects and turns.
This flange is cast upon the said toothed wheel or otherwise securely
attached to the same. The notch of the pawl is provided with small
pivoted metal tongues, which are adjusted to allow the said flange to
pass freely between them when the pawl is free on its pivot. While

page_text: the pawl lever is stationary or moving back the pawl remains free on its
pivot, and therefore has no action on the said flange and wheel, but the
slightest forward movement of the said pawl lever brings the pawl up
against a stop on the said lever and thereby causes the said tongues to
gripe the flange and impart to the same the motion of the said lever;
as the lever arrives at the end of its forward stroke the pawl releases the
flange, which continues its forward rotation while the pawl moves back;
the pawl is provided with a screw for adjusting the said tongues.
From the above description it will be obvious that with this apparatus
there are no "dead points," and that there can be no backward motion
of the wheels. The said toothed wheel gears with a pinion fixed on the
fly wheel shaft, which is fitted to turn freely in suitable bearings in the
said brackets; and in order that a quick motion may be imparted to this
shaft this pinion is made as small as practicable; the said fly wheel shaft
also carries a driving pulley, which is connected by a belt with a pulley
on a shaft of the machine.
In combination with the said fly wheel, I employ a brake consisting
of a plate connected with a lever which is provided with a knob or pin
projecting up through the table; the said brake is kept from contact
with the wheel by a spring, but by depressing the said knob or pin
the brake is caused to act on the said wheel and thereby stop the
machine.