IMPROVEMENTS IN APPARATUS TO BE APPLIED FOR OPERATING SEWING AND OTHER MACHINES
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by Alexander Melville Clark at the
Office of the Commissioners of Patents, with his Petition, on the
31st August 1870.-A communication from abroad by Edward
Jenner Leyburn, of Lexington, County of Rockbridge, State of
Virginia, United States of America.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County
of Middlesex, Patent Agent, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPARATUS TO BE APPLIED FOR OPERATING
SEWING AND OTHER MACHINES," to be as follows:-
This Invention relates to a new and improved mode of operating light
machinery, such as sewing machines and watch makers' lathes, and is
intended to remedy the objections attending the treadle movement, and
in lieu of such movement employ the weight of a person sitting at
a machine to assist such person in obtaining the required power to
drive it.
.
The main object of the first part of this Invention is to arrange the
frame of the machine to be operated, and the seat of the operator thereof

page_text: •
• upon a pivoted frame in such manner that by a light swaying motion of
the operator a rocking motion can be imparted to said frame from which
the necessary power and motion can be derived to operate the machine,.
as will be herein-after more fully described.
The second part consists, first, in the application of a driving belt
wheel to a shaft which forms the axis of an oscillating seat, the latter
having the table of the sewing machine applied to and supported by an
arm extending from and moving with it, in combination with a treadle
which is connected by rods and levers to said wheel and seat arm as will
be herein-after explained; second, in so contriving the connection
between the treadle, the movable scat arm, and the driving belt wheel,
that by a simple adjustment of the upper end of one of the connecting
rods the table and seat can be rigidly fixed, and motion communicated
to the driving belt wheel by means of the treadle motion and without
moving the body; third, in an adjustable foot rest on the treadle in
combination with an oscillating seat having a table applied to an arm
extending from it, whereby the treadle can be adapted for large or small
persons sitting in the scat, as will be herein-after explained.
Figure 1 is a longitudinal section taken vertically through the centre
of the mechanical movement adapted for operating sewing machines;
Figure 2 is an elevation of one side of this Invention applied to the
table of a sewing machine; Figure 3 showing the left hand side of the
seat and its supporting frame. Similar letters of reference indicate
corresponding parts.
In the accompanying Drawings A represents a rectangular base frame
having two ears f,f, rising from its longitudinal side bars to which
another rectangular frame B is pivoted by means of a horizontal cross
rod e.
The frame B is allowed to receive a vertical rocking motion
about its fulcrum or pivot rod e, and between the two frames A, B, at
their ends springs are applied to give uniformity to the rocking move-
ments of frame B. The spring d may be of the semi-elliptical kind,
and the springs S may be of a similar kind, or they may be made of
india-rubber. Upon the frame B on one side of the fulcrum e is
constructed a frame E on which rests a seat F for the operator which
seat can be adjusted to suit different persons by loosening the clamp
screw that passes through the boards G, G'. On the opposite side of
the fulcrum e a frame D is erected upon frame B, on top of which is a

page_text: table J carrying a sewing machine K or some other light driving
machine; L is a balance wheel carrying a belt g which communicates
rotary motion to the driving shaft of the sewing machine K, and T is a
pitman which is connected at one end to a wrist pin eccentrically placed
on one side of the wheel L and at the other end to the longest arm of a
vertically vibrating lever N. This lever N is pivoted at p to the frame E
and its shortest arm is connected by a link to the rear end of the base
frame A at S. It will be seen that rotary motion will be communicated
to the balance wheel L by vibrating the frame B, and that a very slight
motion of this frame is required to effect the object. On the front end
of the frame B at the middle of the length of the front cross bar an
adjustable foot rest c' is applied which can be adjusted vertically by
loosening set screw b₁, and opposite the foot rest c' an adjustable toe
rest c is applied to the front cross bar a of the frame A, and held at any
desired height by the set screw b on which board a spring cushion might
be applied. The operator sits upon the chair F with the feet upon the
floor or preferably upon the stand c', and with the hands upon the
table J in a natural position for guiding the work. The balance wheel
may then be started by hand, after which a slight forward and backward
motion of the body will rock the frame B and keep it in motion. I
have applied a toe rest c in such relation to the foot rest c¹ that the
operator can at will use his toes to assist in rocking the frame B.
The principle of this Invention consists in mounting the operator,
and also the machine which it is intended to operate upon a frame in
such manner that by a slight forward and backward movement of the
body the operator can derive motion and power sufficient to drive the
machine, and while I prefer to communicate motion to the machine to
be driven from the frame B by means of lever N, pitman T, and balance
wheel L, I do not confine myself to these parts as other equivalent
means may be adopted, nor do I confine myself to the foot stand, the
toe board, or the springs d, S, but prefer to adopt these parts and apply
them substantially as set forth. The fulcrum e may be made adjustable
towards or from the rear of the frame A, so as to adapt the machine to
be operated conveniently either by a very heavy person or by a very light
person.

page_text: of the legs of the stand to which a treadle T is applied by pivots s and
to one of which a stud p, p, is fastened which affords a fulcrum for a
connecting rod J; B is a seat frame having applied to it by means of
springs or otherwise a seat S, upon which the operator is supported while
working the machine. The back of the seat may be made elastic or rigid,
adjustable or not, as circumstances require; this seat is jointed by the
standards of its frame to a horizontal shaft or studs cast on inner side of
stool uprights or bar i, on one end of which turns a driving belt wheel D
which also serves as a balance wheel. This seat frame B is constructed
with an arm B³, extending upward and forward in such manner_as_to_
afford support to the table C on which the sewing machine is secured..
The table C thus supported is arranged in a convenient position to a
person sitting in the seat S, and will vibrate about the axis of the shaft
or bar with the scat and the person thereon. Around the small
wheel D¹ of the sewing machine, a belt is passed which being carried
around the driving wheel D will communicate rotary motion to the
shaft of wheel D', when the wheel D is rotated. Eccentrically to the
outer side of wheel D a wrist pin is applied, to which one end of a
pitman P is attached. The other end of this pitman is pivoted to one
end of a vertically vibrating lever L. This lever has its fulcrum at b
and c, c². Two rods are connected to it, one of which J is pivoted at c
to said lever, and at p to the stand A. The other rod K is pivoted at c²
to lever L, and to a wrist pin m at the outer forward corner of the
treadle T. Between the studs or pins c, c², which may be adjustable is
a stud pin c¹, which may be fixed or adjustable, and which is adapted
for receiving the upper end of either one of the rods J, K, when it is
desired to shorten or lengthen the strokes of the lever L or treadle T.
The stud which is fixed to the arm B¹ of seat frame B is made long
enough to receive the upper end of rod J, and when this rod is thus
adjusted it will be seen that it will serve as a brace for rigidly holding
the seat frame when it is desired to operate the machine by the treadle T
alone. The treadle T is pivoted at S to the extensions a of the stand A,
as above stated, so as to receive from the seat of an operator upon the
seat S, an oscillating motion alone or in conjunction with a rocking
motion given to the seat frame and table will be communicated to
lever L through one or both of the rods J, K, and this lever will give a
rotary motion to the shaft D which will rotate the wheel D' as above
described.

page_text: For very light running machines the treadle may be stationary if
desired in which case the rod J will be omitted and the motion obtained
by the action of the body upon the vibrating seat.
It will be seen by reference to Figure 2 that a foot stand t is applied
to the treadle T, and that this stand can be adjusted higher or lower in a
plane parallel to the treadle by means of the set screws y, y, which
connect the stand to posts v, v. This feature is useful in this machine
as it allows the machine to be adjusted to suit a long or short leg.