Improvements in Driving Mechanism for Sewing Machines.
Year: 1887

page_text: Date or Application, 5th July, 1887.
Specification Accepted, 5th Aug., 1887.
Communicated from abroad by THE SINGER MANUFACTURING COMPANY, of New
York, in the United States of America, Sewing Machine Manufacturers.]
Communicated from abroad by THE SINGER MANUFACTURING COMPANY, of New
York, in the United States of America, Sewing Machine Manufacturers.]
Improvements in Driving Mechanism for Sewing Machines.
I, JOHN KING MACDONALD, Manager of the Singer Manufacturing Company, of
Kibowie, Dumbartonshire, 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 :-
My invention relates to a driving mechanism for sewing machines of such con-
struction that the inconvenience incidental to removing the belt from the driving
pulley when the machine is turned up on its hinges, to give access to the mechanism
beneath the bed-plate, may be avoided.
In carrying my invention into effect I provide a compound driving pulley the axis
of which is in line, or nearly so, with the pivots or hinges by which the machine is
secured to its table or to brackets supported thereby, and on which said machine
swings when it is turned up or down. This compound pulley has two grooves for the
reception of two endless belts one of which runs from a pulley on the driving or
power shaft beneath the table to the said compound pulley and the other from the
latter to the pulley on the driving or main shaft of the sewing machine.
I prefer to construct my compound pulley in the form of a clutch one portion of
which may run loose from the other at times, the two parts of the pulley being
adapted to be coupled and run together when desired. The clutch is operated, to
apply or disconnect the power, by a clutch lever connected with a treadle controlled
by the operator.
.
In the drawings figure 1 is an end view of a button-hole sewing machine with the
invention applied thereto. Figure 2 is a partial elevation of the same, and figures 3
and-4 are sections of compound driving pulleys.
A, denotes the table of the machine and B one of the side frames of the stand by
which the table is supported. C, is the bed-plate of the machine and D the arm.
With ordinary family machines the hed-plates thereof are usually hinged directly to
the tables, but with button-hole sewing machines it is found most convenient to hinge

page_text: the bed-plates to brackets, as E, attached to the table. On the driving shaft F, of the
machine is an ordinary pulley G, connected by an endless helt H, with a compound
pulley I, i, the axis of which is in line, or nearly so, with the hinges or pivots, at e,
on which the machine turns when swung backwards to the position indicated by dotted
lines in figure 1. J, is a second endless belt connecting the compound pulley with a
pulley K, on a power or driving shaft, as L, beneath the table.
I prefer to construct my compound pulley in the form of a friction clutch, as more
clearly shown by figure 3, the part on which the belt J, runs, being adapted to be
pressed towards the part I, by the clutch-lever M, connected by a rod N with the
treadle O. The part I of the clutch or compound pulley runs loose on a stud or pin a
sustained by a standard 6, on the table A, and the part i runs loose on the hub of
the part I. Between the said parts I prefer to employ a spring e, made in the form
of a washer or a spider-spring, and a washer d, against which the said spring a bears,
these devices forming the frictional connections between the parts of the clutch. The
clutch-lever presses against a centre-plug or button h. If desired a retracting
spring, as P, indicated by dotted lines in figure 2, may be employed to disconnect the
parts of the clutch.
The compound pulley may be of any suitable size to impart the requisite speed to
the driving shaft of the machine from the power shaft and may consist of a friction
clutch as shown in figure 3, or of a single solid pulley 1', with two belt grooves, (see
figure 4) or of two separate grooved pulleys mounted on the same shaft.
From the foregoing it will be apparent that as the axis of the compound pulley is
in line with the hinges of the machine the latter may be turned over to the position
indicated by dotted lines in figure 1, without disturbing the driving belts, and that
the power may be conveniently applied to the machine by the treadle-operated clutch-
mechanism above described.
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, I declare
that what I claim is:-
1. The combination with a sewing machine bed-plate, a table, and pivots or hinges
for enabling the former to be turned up on the latter, of a compound pulley constructed
to form a friction clutch and having its axis in line with the hinge-pivots, the driving
pulley, the power pulley and the two endless belts, substantially as set forth.
2. The combination with the table, the sewing machine bed plate and the brackets
to which the latter is hinged or pivotted, of a compound pulley having its axis in
line with the hinge-pivots, the driving pulley, the power pulley, the endless belts, the
clutch lever, the connecting rod and the treadle, substantially as set forth.
Dated this Fourth day of July 1887.