US2254017A - Shoe sewing machine - Google Patents

Description

Aug- 26 1941- A. R. MORRILL 2,254,017

SHOE SEWING MACHINE Filed Sept. 30, 1938 @gw l WWW Patented Aug. 26, 1941 snor sawme MACHINE Allred R. Morrill, Beverly, Mass., assignor to United Shoe Machinery Corporation, Borough ofV Flemington, N. J., a corporation of New Jersey Application September 30, 1938, Serial No. 232,546

4 Claims.

The present invention relat to inseam shoe sewing machines such as are used for sewing the uppers to the soles of turn shoes or the welts and uppers to the insoles of welt shoes. An example of this general class of machines is illustrated in the present inventors prior Patent No. 2,041,945 of May 26, 1936, and in the patent to Eppler No. 1,108,560 of August 25, 1914.

A machine of the class described in the patents referred to is provided with a curved hook needle, a welt guide, if a welt shoe is being operated upon, and a work rest or back gage against the forward end of which the shoe is moved during the sewing operations. The back gage ordinarily engages the bulging upper of the shoe close to the point of operation of the needle and, as the sewing operation progresses around the shoe, the shoe upper rubs against the forward end of the back gage in an irregular manner, the backv gage steadying the shoe from any movement caused by the action of the stitch forming devices. In order to prevent the upper, as it rubs along the met-allic surfaces of the back gage, from being marked or otherwise damaged where shoes having light colored or fancy uppers are being sewn, it is ordinarily necessary to cover the forward end of the back gage with leather or cloth or to provide a. protective covering to the shoe around the bulging portions of the upper engaged by the back gage'. The use of a cover on the back gage tends to increase the frictional effect on the shoe as it rubs along the back gage during sewing operations so that manipulations of the shoe in presenting it to the stitch-forming devices is rendered more difcult. Also, a leather or cloth cover, such as commonly used, wears out quickly and requires frequent replacement. A covering for the shoe adds to the expense of manufacture and must be discarded when the shoe is completed.

The object of the present invention is to improve the construction and mode of operation of a welt and turn shoe sewing machine so that the movement required to change properly the positions of the shoe as the operation progresses during the sewing will meet with less resistance than heretofore, while at the same time the necessity on the part of the operator of taking special precautions against marking or otherwise injuring the nished surfaces of a shoe upper is avoided. With this object in view, a feature of the present invention contemplates the provision in an inseam shoe sewing machine of aback rest, the forward end of which has secured to it a friction reducing wear plate of synthetic resin.

The advantages gained by the use of a wearing surface of synthetic resin is that a polish higher than ordinary can be obtained easily on such surface and that such surface has an inherent lubrieating effect without any tendency to markor otherwise injure a shoe upper as the shoe is being operated upon.

It is the usual practice to heat the thread handling devices of a shoe sewing machine of the type referred to for the purpose of maintaining the wax with which the thread is impregnated in workable condition and, in so doing, all of the parts of 4the machine become heated. and the underlying parts, particularly the wearing surface of the back gage, are exposed to the particles of hot wax, oil, and other materials which are thrown of! by the operation of the stitch forming devices. Deposits of Wax or oil, together with the heating of the parts, may have undesirable effects on the resinous part of the back gage wear plate, unless special precautions are taken, causing it to warp or become loosened so as to result in an irregular guiding action on the shoe. A further feature of the invention, therefore, consists in forming a non-metallic friction reducing wear plate, whether of synthetic resin or other similar material, with angularly disposed surfaces arranged to lock the wear plate. in place. By this arrangement, loosening of the wear plate, by reason of distortion from heat of other causes, will not result in displacement of the wear plate so as to prevent the position of theshoe from being changed properly as the sewing progresses.

Other features of the invention consist of certain constructions, arrangements, and combinations of parts, the advantages of which will be obvious to one skilled in the art. The various features of the invention will be clearly understood from the following detail description and the accompanying drawing in which Fig. 1 is a right hand side elevation of a portion of a shoe sewing machine embodying the present invention; and Fig. 2 is an enlarged perspective view of the back gage slide and wear plate illustrated in separated relation.

The sewing machine illustrated in the drawing is provided with the usual stitch-forming instrumentalities, including a curved hook needle 2, a curved awl 4,. a looper 6, a thread iinger 8, a channel guide 9, a welt guide I0, and a backrest or back gage slide l2 pressed yieldingly within a guideway I3 towards the front of the machine. The back rest slide and the other operating parts of the illustrated machine are similar to those in the machine of inventors patent above referred to, except for the work-engaging end of the back rest slide and the construction and arrangement with relation to the back-rest guideway of the thread end holder, as will be hereinafter more fully described.

The forward end of the back-rest slide of the machine embodying the present invention is provided with a plate I4 of phenolic or other similar synthetic resin, the wearing surface I6 of which is highly polished to reduce toa minimum the frictional effect of the back gage on the shoe as it is being fed and as its position is changed during formation of an inseam. The plate is removably secured on the slide and locked in psition by suit-able angularly disposed surf-aces on the plate and back-rest slide.

The wear plate I4 is preferably formed by molding a phenolic or other synthetic resin ma- 'terial about a metallic insert I8 having an open ended slot, the opposite edges of which insert are -beveled to provide a rm grip on the molded material. Along the central part, the plate I4 is -channelled as at 20 to receive a forwardly projecting tongue-like portion of a lug 22 on the forward end of the back-rest slide, and the lug carries a bolt 24, the head of which is shaped to enter the open end of the slot in the insert I8 and slide within a cut-away portion of the insert so that, when tightened, the bolt will clamp the plate I4 to the forward end of slide I2. The side edges of the lug 22 in the channel 2B of the wear plate and the bolt 24 in the slot of the insert I8 thus prevent movement of the plate on the back rest slide horizontally in the direction of feed even if the clamp bolt 24 is loosened.

Due to the usual practice of heating machines of this type and to the general abuse from gonstant impact with the work and vibration of the operating parts of the machine, the plate I4 may become distorted in use or the metal insert IB loosened from the position in which it is molded in the plate. In order to avoid the possibility that the plate will become displaced vertically from its position at the end of the back-rest slide, the opening ofthe slot in the insert I8 is arranged to receive the head of the bolt only from its upper end, and the plate I4 is provided with overhanging ledges 26 arranged to lock the plate I4 from downward movement by engagement with shoulders 21 on the slide I2 when the plate is forced rearwardly against the slide. The ledges 26 extend laterally beyond the channel 20 and when seated on the shoulders 21, the bolt 24 bears against the lower end of the slot in the insert I8. Thus, any pressure of the plate against the slide, either when clamped by the bolt 24 or from the force of the shoe against the plate, tends to hold the plate in proper position on the forward end of the slide, even though the bolt 24 has been loosened or the insert I8 has been freed from the grip of the plate I4.

To frictionally retain the end of sewing thread vices. When the end of thread indicated at 29 is engaged by the thread retaining device 28, the thread extends past the thread linger 8 from the looper B, thus insuring that the needle will be looped in proper manner before the thread is pulled loose from the retaining device. The thread retaining device forms no part of the present invention and may be of any suitable construction. It is secured in place by means of a screw 30 passing through a sleeve 32 and screwing into the back rest guideway I3.

The nature and scope of the invention having been indicated, and its preferred embodiment having been specifically described what is" claimed is:

1. An inseam shoe sewing machine having, in combination, a back rest slide, and a. wear plate secured to the forward end of the back rest slide having a non-marking polished surface of synthetic resin against which the upper of a shoe being operated upon can rub without being marked or otherwise injured. l

2. An inseam shoe sewing machine having, in combination, stitch forming devices, a back rest slide below the stitch forming devices, a moldable resin friction reducing wear plate at the forward end of the back rest slide and means for securing the wear plate to the back rest slide,

' comprising a clamp bolt, means for slidably atwhile starting a new seam, the machine illustrattaching one end of the bolt to the wear plate, cooperating tongue and channel surfaces for preventing relative movement of the wear plate and back rest slide in the direction of feed, and other surfaces for preventing relative movement of the wear plate and back rest slide in the direction of the tongue and channel surfaces when the clamp bolt is tightened.

3. An inseam shoe sewing machine having, in combination, stitch forming devices, a back rest slide below the stitch forming devices, a moldable resin friction reducing wear plate at the forward end of the back rest slide and means for securing the wear plate to the back rest slide, comprising a clamp bolt, a metal insert in the wear plate having an open ended cut-away portion for releasably receiving one end of the bolt, and angularly disposed surfaces on the wear plate and on the back rest slide for preventing relative movement of the wear plate in the direction of the slot in the metal insert when the clamp bolt is tightened.

4. An inseam shoe sewing machine having, in combination, stitch forming devices, a back rest slide below the stitch forming devices, a moldable resin friction reducing wear plate at the forward end of the back rest slide and means for securing the wear plate to the back rest slide, comprising clamping means, cooperating tongue and channel surfaces on the wear plate and back rest slide for preventing horizontal movement of the wear plate on the slide and ledges on the wear plate arranged to engage shoulders on the back rest slide, said ledges and shoulders extending laterally beyond the tongue and channel surfaces.

ALFRED R. MORRILL.

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