Improvements in and relating to Boot and Shoe Sewing Machinery.
Year: 1899

page_text: Date of Application, 23rd Dec., 1899-Accepted, 10th Feb., 1900
COMPLETE SPECIFICATION.
Improvements in and relating to Boot and Shoe Sewing Machinery.
I, JOHN THOMAS RUSH, of No. 13, Burns Street, Northampton, in the County of
Northampton, Shoe Factory Operative, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:-
The present invention relates to sewing machines for uniting the outsoles to
welts of boots and shoes, and more particularly to certain improvements in the
presser foot mechanism of the machine disclosed in Letters Patent of Great
Britain granted to Alfred George Brookes of 55 and 56 Chancery Lane in the
County of London, Chartered Patent Agent, on a communication from Jonathan
Munyan, of Worcester, in the State of Massachusetts, one of the United States
of America, No. 7793 of 1892.
In the device disclosed in the patent above referred to the presser foot is
normally held under a relatively light spring pressure against the work during the
feeding movement. After the feeding movement and before the awl enters the
work to feed it another stitch interval, the pressure is increased, and by means of
a locking device, the pressure foot is locked in its position of extreme pressure.
In the device of the patent above referred to, the pressure exerted by the presser-
foot is dependent upon the force exerted by the spring controlling the same, and
since the pressure exerted by the spring prior to its increase as hereinbefore
stated, must be sufficiently light to allow the work to be fed along under the
presser-foot, it is difficult to secure sufficient increase of pressure to closely clamp
together the welt and outsole, particularly in heavy work.
Furthermore, with any form of locking device known to me, intended to lock
the presser foot in its position of greatest pressure, there is a liability of a failure
of positive action, so that after being pressed together the welt and sole are per-
mitted to separate to a greater or less degree, during the puncturing movement
of the awl, thus requiring an extra strain on the stitch forming devices which
must thereafter operate while setting the stitch to draw the upper and welt
together.
In accordance with the present invention, the presser-foot is normally held
against the work by spring pressure and thereafter during its final clamping
action is given a positive movement and positively held in its position of greatest
pressure without the employment of separate locking instrumentalities, thus both
simplifying the presser foot mechanism, and materially improving the operation
of the machine and the quality of the work.
To the above end the present invention consists of the improved presser foot
mechanism hereinafter more particularly described in this specification and
defined in the claims thereof.
The accompanying drawings show the form of my invention and illustrates in
side elevation so much of a sole sewing machine as is necessary to show the con-
nection of my invention thereto.
The stationary work-support 1, the presser-foot 2, the presser foot lever 3, the
auxiliary presser-foot lever 4, the link 5, and spring 6, for connecting the said

page_text: presser-foot levers, the presser-foot actuating lever 7 and its cam 8, the stud 9,
the frame 10, its connecting mechanism and the spring 11, for supporting said
frame and the hand lever 12, are and preferably will be, except as to differences
hereinafter pointed out, the same as shown and described in the Letters Patent
herein before referred to.
The present invention contemplates the actuation of the presser-foot for a
certain part of its movement by yielding means and thereafter imparting to it
a further positive movement and to these ends any suitable means may be employed
which will accomplish such results. In the illustrated embodiment of my inven-
tion, the presser-foot actuating lever 7, oscillated by the cam 8 actuates the
auxiliary presser-foot lever 4 through the spring presser pawl 13 engaging the
ratchet toothed dog-14 on the rearwardly projected end of the lever 4, and the
presser foot lever 3 by means of the link 5 through the intervention of the spring 6
is yieldingly actuated to depress the presser foot 2 which yielding movement
continues until the resistance of the material balances the pressure of the spring 6
and arrests further downward movement of the presser-foot, when the auxiliary
lever 4 engages a suitable stop rigidly connected with the presser-foot lever 3
and projected into the path of further movement of the auxiliary lever 4, where-
upon the auxiliary lever 4 picks up the presser foot lever 3 and moves it with
a positive unyielding movement to cause the presser-foot to positively clamp the
layers of the stock together and against the work support during the formation
of the stitch by the stitch forming devices.
Any suitable form of stop may be employed for this purpose the stop of the
machine of the drawing comprising an adjustable pin 16 screwed into a lug 15
on the base of the hand lever 12, the lug 15 projected outward over the auxiliary
lever 4 so as to bring the stop 16 over the auxiliary lever 4. A suitable nut 17
screwed on the pin 16 maintains said pin in proper adjustment.
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. In a shoe sewing machine, the combination with a work support, of a presser
foot, mechanism for actuating the presser foot, a spring interposed between the
presser foot and its actuating mechanism whereby the actuating mechanism
imparts an initial yielding movement to the presser foot, and a stop or shoulder
arranged to be engaged by the presser foot actuating mechanism to impart a
subsequent positive work clamping movement to the presser foot, substantially as
described.
2. In a shoe sewing machine, the combination with a work support, of a presser
foot, a presser foot lever, a stop on said presser foot lever, an auxiliary presser
foot lever arranged to engage the stop to impart a positive clamping movement
to the presser foot lever, a spring connection between the presser foot lever and
auxiliary lever, and means to actuate the auxiliary lever, substantially as
described.
Dated the 22nd day of December 1899.