IMPROVEMENTS IN MECHANISM FOR CONVERTING MOTION ESPECIALLY TO THE SHUTTLE MOVEMENT OF SEWING MACHINES
Year: 1883

page_text: "
LETTERS PATENT to Sydney Pitt of Sutton in the County of Surrey for an
Invention of "IMPROVEMENTS IN MECHANISM FOR CONVERTING MOTION
ESPECIALLY TO THE SHUTTLE MOVEMENT OF SEWING MACHINES Com-
municated to him from abroad by Lebbeus Baldwin Miller of the City of
Elizabeth in the County of Union and State of New Jersey United States of
America
PROVISIONAL SPECIFICATION left by the said Sydney Pitt at the Office
of the Commissioners of Patents on the 18th March 1883.
SYDNEY PITT of Sutton in the County of Surrey "IMPROVEMENTS IN MECHANISM
FOR CONVERTING MOTION ESPECIALLY TO THE SHUTTLE MOVEMENT OF SEWING
"
MACHINES [Communicated to him from abroad by Lebbeus Baldwin Miller of
the City of Elizabeth in the County of Union and State of New Jersey United
States of America]
The object of the said mechanism is to obtain from a common reciprocating
motion, an oscillating movement which can if desired be increased to more than
half a circle.
In the drawings Figures 1 and 2 are face views and Figure 3 is an edge view of
such mechanism which is shown as applied to a sewing machine beneath the bed
plate.
A represents the lower end of a revolving shaft from which by means of a
crank a or equivalent motion is communicated to the connecting rod B the other
end of which is pivotted to the lever C at the point b between the two links D
and E which are also respectively pivotted to said lever C at the points d' and e¹
and to the bed plate G at the points d and e thus forming swinging fulcrums for
said lever-The end of said lever C is provided with a pin, roller or projection f
adapted to enter a slot in the outer end of the crank F of the upright shaft ; which
passes through the bed plate and to which above the plate is attached the shuttle
carrier.

page_text: As the shaft A revolves it communicates to the connecting rod B a reciprocating
movement. The lever C receiving this motion at the pivot b is controlled and
guided in the lines shown on one side of said pivot by the link D and on the other
side by the link E and the result is that the end of it, provided with the projection f¹
receives an elliptical oscillating motion in the line g and said projection acting in
the slot of the crank F, gives said crank and its vertical shaft the required
oscillating motion.
The extent of this movement may be varied at will by varying the length, or
changing the position of the fixed pivots, of the controlling links or either of them
or changing the position of the centre of the crank F.
"
While I prefer to pivot the connecting rod B to the lever C at a point midway
between the link pivots in order to get a parallel" motion, the same result will
be obtained, in the oscillation of the crank shaft, from a given amount of recipro-
cation, if the connection be made at any point on said lever C, or if motion be
given through one of the controlling links.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Sydney Pitt in the Great Seal Patent Office on 12th September
1883.
"
SYDNEY PITT of Sutton in the County of Surrey "IMPROVEMENTS IN MECHANISM
FOR CONVERTING MOTION ESPECIALLY TO THE SHUTTLE MOVEMENT OF SEWING
MACHINES A Communication to me from abroad by Lebbeus Baldwin Miller
of the City of Elizabeth in the County of Union and State of New Jersey United
States of America
The object of the said mechanism is to obtain from a common reciprocating
motion an oscillating movement which can if desired be increased to more than
half a circle.
In the drawings Figures 1 and 2 are face views and Figure 3 is an edge view of
such mechanism which is shown as applied to a sewing machine beneath the bed
plate.
A represents the lower end of a revolving shaft from which by means of a
crank a or equivalent motion is communicated to the connecting rod B the other
end of which is pivotted to the lever C at the point b between the two links D
and E which are also respectively pivotted to said lever C at the points d¹ and e'
and to the bed plate G at the points d and e thus forming swinging fulcrums for
said lever. The end of said lever C is provided with a pin roller or projection fl
adapted to enter a slot in the outer end of the crank F of the upright shaft ; which
passes through the bed plate and to which above the plate is attached the shuttle
carrier.
As the shaft A revolves it communicates to the connecting rod B a reciprocating
movement. The lever C receiving this motion at the pivot b is controlled and
guided in the lines shewn on one side of said pivot by the link D and on the
other side by the link E and the result is that the end of it provided with the
projection f receives an elliptical oscillating motion in the line g and said
projection acting in the slot of the crank F gives said crank and its vertical shaft
the required oscillating motion.
The extent of this movement may be varied at will by varying the length or
changing, the position of the fixed pivots, of the controlling links or either of them
or changing the position of the centre of the crank F.
While I prefer to pivot the connecting rod B to the lever C at a point midway
between the link pivots in order to get a parallel" motion, the same result will
be obtained, in the oscillation of the crank shaft from a given amount of recipro-
cation if the connection be made at any point on said lever C or if motion be
given through one of the controlling links.
What I claim and desire to secure by Letters Patent is -
In a sewing machine the combination with a rock shaft having a slotted crank
of a lever provided with a projection adapted to enter and work in such slot, said
lever being attached to a bed plate by swinging links pivotted on opposite sides of
it, and also connected to regularly reciprocating mechanism substantially as
described.
In witness whereof I the said Sydney Pitt have hereunto set my hand and
seal this thirtieth day of August in the year of our Lord One thousand eight
hundred and eighty three.