Improvement in Treadle Mechanism.
Year: 1897

page_text: Date of Application, 26th Oct., 1897-Accepted, 5th Feb., 1898
Improvement in Treadle Mechanism.
I, JOHN FRANK WILKINSON, of East Pepperell, in the County of Middlesex and
State of Massachusetts, United States of America, Gentleman, do hereby declare
the nature of my invention, and in what manner the same is to be performed, to
be particularly described and ascertained in and by the following statement:
This invention has for its object to produce an improved device for machines
employing a treadle mechanism, for throwing the crank off of a dead center, and
for starting the driving-wheel in the proper direction when the treadle is operated,
and preventing it from rotating in the wrong direction.
To this end the invention consists of the improved device which is illustrated on
the drawings and which I shall now proceed to describe in detail and then point
out in the claims hereto annexed.
Reference is to be had to the annexed drawings and to the letters and figures
marked thereon, forming a part of this specification, the same letters designating
the same parts or features, as the case may be, wherever they occur.
Figure 1 shows a top plan view of a sewing-machine treadle provided with an
attachment embodying my invention.
Figure 2 represents a section on line 2-2 of Figure 1.
Figure 3 is a side elevation of a portion of a sewing-machine provided with said
treadle.
Figure 4 is an enlarged detail view, showing the crank-shaft and the clutch
thereon, which latter is connected with the supplemental treadle.
Figure 5 is a partial section on the line 5---5 of Figure 4, looking in the direction
of the arrow.
My invention is adapted to be used in connection with the treadle and driving-
wheel of a machine of any pattern or class; but for the sake of illustration I have
shown it as being attached to a sewing-machine frame a provided with a bracket b
in which the crank-shaft c is journalled.
The treadle d is mounted on a shaft e at the base of the standard, and is con-
nected at its upper end with the crank by the pitman-rod f pivoted to said crank-
shaft and to a pin g formed on the said treadle. On the crank-shaft is rigidly
mounted a driving-wheel i. Thus far the machine described is no different from
those now in use. .
My improvement comprises a supplemental treadle j, located over the treadle
in position to receive pressure from the ball of the foot when the latter is on the
treadle.
The supplemental treadle ; is yieldingly supported above the treadle d, so that
when first pressed downwardly it will yield and move independently of the
treadle d. The preferred means for securing and supporting the supplemental
treadle are shown clearly in Figures 1 and 2, and comprise a bar j¹ to which the
supplemental treadle j is directly attached, and a spring one end of which is
attached by bolts to the bar 1, while its other end is attached by bolts j to a
clamping-plate ja bearing against the under side of the treadle d. A comple-
mental clamping-plate bearing on the upper side of the treadle is secured by
screws to the plate, said screws passing through openings in the treadle .
The spring normally raises the supplemental treadle to the position shown in
Figures 1 and 3.

page_text: The bar is bent upwardly to form an ear 18 which is connected to the lower
end of a rod o, the upper end of which is connected with the arm q of a clutch r
on the crank-shaft.
The clutch may be of any approved construction, but I prefer one which is
noiseless in its operation. The clutch allows the driving-wheel and the crank-shaft
to revolve freely in the direction of the arrow shown in Figure 3, but locks it
against rotation in the opposite direction. Hence when the supplemental treadle j
is depressed, even though the pitman and the crank are on a dead center, it will
start the shaft in the direction of the arrow far enough for the treadle to revolve
the driving-wheel when it is depressed. Hence it will be seen that at no time will
the driving-shaft be allowed to rotate in the wrong direction, and that upon start-
ing the machine to work, the driving-shaft is given its initial movement without the
help of the hands which is generally given to the rotating parts of machines
without attachments of this nature. The contact of the bar j with the under
side of the main treadle limits the upward movement of the supplemental treadle.
In case it is desired to equip a machine in which the driving-shaft rotates in the
opposite direction, with my improvement, the clutch is merely reversed, as will be
readily understood. Preferably the arm q is slightly shorter than the offset or
crank arm of the crank-shaft, in order to allow for a slight movement of the clutch
before it is locked to the shaft.
It will be understood that I do not limit myself to the means here shown for
securing and supporting the supplemental treadle, since said means may be varied
to suit any particular style of treadle.
The yielding support of the supplemental treadle above the main treadle
relieves the jar on the operator's foot or feet which attends the reversal of the move-
ment of the treadle, and thus makes the operation of the machine easier and less
fatiguing and trying to the operator.
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
1. The combination with a driving-wheel, a crank, a pitman, and a main
treadle, forming a treadle mechanism of a clutch on the crank-shaft, a supple-
mental treadle connected to the said clutch and located over the forward or toe end
of the main treadle, so that both treadles can be moved simultaneously by the same
foot or feet, and a spring connection between the supplemental and main treadles,
whereby the supplemental treadle is yieldingly raised and separated from the main
treadle and permitted to move toward the latter by downward pressure of the
operator's foot, while the main treadle is being operated, the yielding support of
the supplemental treadle relieving the jar on the operator's foot..
2. The combination with a driving-wheel, a crank, a pitman, and a main treadle,
of a clutch on the crank-shaft, a rod connected with said clutch, a supplemental
treadle located above the main treadle, a bar supporting said supplemental treadle
and connected with said rod, a spring yieldingly supporting said bar, and means
for securing the spring to the main treadle.
Dated thin and 1
1000
JOHN FRANK WILKINSON.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.