US2346246A - Sewing and cementing machine - Google Patents

Description

April 11, 1944 FQAsHwoRTH 2,346,246

SEWING AND CEMENTING MACHINE Filed Feb. l5, 1941 2 Sheets-Sheet l April 11, 1944.

F. ASHWORTH.

SEWING AND CEMENTING MACHINE Filed Feb. 13, 1941 2 sheets-shed 2' Il x Patented Apr. 11, 1944 2,346,246 SEWING AND CEMENTING MACHINE.

FredY Ashworth, Wenham, Mass., assigner to United' Shoe Machinery Corporation, Fleming:- ton, N. J'., a corporation of New J ersey Application February -13, 1941,1seria1 No. `378,764

(o1. i12-4.3)v

12. Claims.

The present` invention relates to sewing machinesV and more particularly to machines. for attaching a welt strip by both-.stitches and. cement along the edge. of a shoe outsole.

If. devices are appliedV to a sewing machinefor performing cementi'ng operations simultaneously with the sewing operations, difliculties oftenoccur duringthe distribution ofsoftened or uid adhesive material employed in. the cementing operationsin preventing undesirable accumulations onthe stitch forming devices or other. portions ofthe machine.` Also, unless special attention is given by the operator of the machine, the parts being sewed sometimes-becomestucktogether in improper relationship before the sewingv point in` the machine is reached. orY a free portionofthe sewing thread itself will come into contact with the fluid adhesive, causingthe adhesive to be thrown in all directions by the whipping` action of theV threadduring stitch formation. To overcome these. diculties, the. usual practice' is to.

apply adhesive as close as possible to the. point-,of operation of the stitch forming. devices in themachine,.so that-there is small opportunity for accumulations of adhesive onthe machine orchance for the adhesive to come. in. contact with. the thread before the. sewing` point. is reached. As-a further means of avoidingdimculty when cementing operations are performed simultaneously with the sewing, the adhesive may be applied to one or both of the parts to be sewed. before. presenting to the machine and allowed' to become cured or otherwise rendered inactive. During sewing operations, the adhesive then is activated by heating or by applying a liquid activating agent. By so doing, application of the adhesive itself` in a softened state and `consequent misplacement of the adhesive is avoided.

Sewing machines usually are equipped with work clamping means, in the form of a work support and a presser foot, for compressing and holding the Work for the stitch forming devices. If the activating liquid is applied too close to the operating point of the stitch forming devices, the adhesive will not have become suiciently impregnated to form a secure bond between the parts on which the adhesive is used, the pressure of the clamping means being exerted too soon to compress the parts. intimately together throughout the areas to be cemented.

Among the quickest acting adhesives in common use are those containing cellulose and employing a highly volatile andinammable activating agent, such as acetone, ether, etc. Even with such adhesives, if the activating agent is applied close to orkat the. operating point of' a sewing machine according to previouscementng practices, complete activation does not occur intime for the clamping means to force the parts into intimate contact,r so that full benefit ofthe adhesive in 'securing .an effective cement bond is not obtained. A

Accordingly, it is an object of the present invention to provide/a novel and improved sewing machine in whichy the parts operated' uponmay be cemented' with a ysecure bondthroughout asubstantial area while being sewn together-,without in any way affecting adversely the4 sewingoperations or requiring special attentionon the part of the operator towardsikeeping accumulations of adhesive. off the machine or preventing the parts operatedupon. from being prematurely stuck Other objects are to provide a simple r together. and inexpensive attachment for shoe sewing machines for applying. fan activating liquid to the parts operatedupon, which partshave beenprepared with a layerv of inactive adhesive, the arrangement being such that by the time the parts have reachedthe point of operation of the machine, the adhesive layer willv have become sulficiently impregnated. and softened4 to permit the adjacent surfaces to. be brought intimately together with asecure cement'bond simultaneously with the sewingoperations;

It is within the scope of the present invention to cement two or'more materials in any form or shape together while being operated upon in a sewing machine, the work clamping means of the. machine actingjnotv only to hold the workin proper relationship with the' stitch forming devices of the machine, but'alsoto exert a pressure to bring the partsintofintirnate contact; although in the illustrated embodiment of the invention, means is provided for applying" activating liquid to an inactive layer of vadhesive* carried on a welt strip; said liquid' applying'means being located along the strip suiclentl'y inv advance ofv the clamping means to permit the adhesive layer to become impregnated substantially to its full thickness` in the time requiredA for the. weltv to travel from the applying means to the clamping mea-ns at the normal sewingfspeed of the machine. With the type of cellulose` containing adhesive referred'. to and with thek usual volatile solvents employed with this adhesive, suitable impregnation requiresV threeV to five seconds 'and the liquid applying means is spaced sufficientlyv from the clamping means to provide this' time interval. In the villustrated form' offthi's featurea tubular covering is employed for ther adhesive covered strip after passing the means for applying the activating liquid so that the liquid will not escape by evaporation or otherwise, particularly during those periods when the machine is at rest. With a covering for the activated adhesive, it is unnecessary to take special precautions in starting a seam to insure that the softening action of the activating liquid is not lost.

Further features ofthe invention relate to a simple and effective arrangement for adjusting the quantity and for regulating the distribution of activating liquid along the surface of the adhesive layer on the parts being sewn and to a mechanism for shutting off the flow of activating liquid when sewing operations are terminated.

These and other features of the invention con# sist in certain novel constructions, combinations` and arrangements of parts hereinafter described sewing shaft 22 and suitable mechanisms driven thereby. To start and stop the machine, there are provided treadle controlled driving and stopping mechanisms including a link 24, a lever 26 tol which the link is connected, and a shaft 28 on which the lever is secured for raising the presser foot from the work support at the end of a seam and for performing other operations incl dent to the completion of the sewing operations. The work support I8 of the machine is provided with a welt guiding passage 3 0 adjacent to and in alinement with the point of operation of the stitch formingv device through which the welt and claimed, the advantages of which will'be readily understood by those skilled in the art from the following c lescriptionandv from the acf` companying drawings, in' which Fig. 1 is aviewjin sideelevation'and in' section of certain portions of a shoe sewing'rmachine embodying the features of the invention ;'Fig. 2 is a sectional View of a shoe illustrating the `arrangement of a weltstrip which is sewed and cemented simultaneously on the machine ofFig. 1; Fig. 3 is a detail plan view onan'enlarge'd, scale o f lthe work support and, activatingliquid applying attachment; and if# Fig. 4 is a sectionalviewon a still further enlarged scale'of the liquid applying and spreading device illustratinggits action on an adhesively coated welt strip.

The machine `of the present invention is pro- :i:

vided with means for directing a'welt strip into a seam being sewn and to cement the strip securely in place Vsimultaneo'usly'vvith the sewing operations.v The machine is intended to' operate on a shoe having an outsole previously attached, such asa cementedor stitchdowntype of shoe in which one edge ofthe welt strip is pressed firmly into the crevice formed by the outturned margin oftheupper between the 'bulging sides of the upper and the projecting margin of the outsole. Such avshoe is illustrated in Fig. 2 of the drawings and is composed of an upper 2 secured in lasted relationship with a canvas sheet 4 forming an insole or mid-sole for the shoe by an inseam Bainserted on a machine disclosed in U. S. ff

Letters Patent of Fredericksen, No. 2,246,993, of June 24, 1941. vThe lasted upper and mid-sole, after being sewn together, on this machine, have their projecting marginal portions trimmed olf close to the inseam and the .resulting shoe has cemented to its tread surface an outsole 8 suitably shaped to provide fa projecting-marginal portion. The shoe with the outsole 8 thus attached is then. operated upon by the present machine, simultaneously to sew and cement the welt strip, indicatedat I0, 'to the projecting marginal portion of the outsole with the inner edge oi" the Vwelt strip held securely in the crevice formed by the bulgingl upper and the outsole.

'I'he machine illustrated in the drawings is a lockstitch outsole shoe sewing machine similar in construction and manner of operation to that disclosed in U. S. Letters Patent No. 1,169,909 of February 1, .1916, of the present inventor, and of the same inventor and another, No. 2,271,611 of February 3, 1942. Referring to Fig. 1, of the drawings, the machine'has a curved hook needle I2, a rotary shuttle I4, a looper I6, a work support I8, a presser foot 20, and other stitch forming and thread handling devices operated by a strip I0 is led tothe sewing point and against the shoe at the sewing point between the work support and presser foot. To t closely within the crevice formed by the bulging upper and projecting margin of the insole, the inner edge of the welt strip Ill" is beveled somewhat so that when secured in close fitting relationship with the crevice, a tight joint is secured..

Before use vof the welt strip I0, one side surface and the surface of the beveled edge is` coated with a layer 3I of quick drying cellulose containing adhesive which is allowed to become at least partially cured before use. To cement the welt while sewing, this' layer of adhesive is activated by thorough softening so that a secure bond will he formed with the outsole. The activating agent consists of a liquid including acetone, ether, alcohol, or other similar highly volatile and ordinar- `ily combustible organic solvents, the welt being are pressed into intimate contact. By thoroughly impregnating the layer of adhesive to a substantial depth, full benefit of Athe clamping pressure of the presser foot on the resulting bond is obtained so that after the parts leave the point of operation of the machine and the adhesive hardened, they are securely cemented as well as attached by stitches.4

To apply the activating liquid a suihcient distance away from the point of sewing and clamping operations, the welt strip i9 is led through slots adjacent the lower closed end wall of :i cylindrical cartridge 32 through the upper open end of which the activating liquid is introduced. The cartridge 32 is slidably mounted on a sleeve 34 having inserted at its lower end a plug or pad of absorbent material 38. The upper end of the tube 34 has an internal thread engaging an external thread on a hollow terminal 38 for a tu bular conductor til, the upper end of which is connected to a flow controlling valve 42 secured 'It the cartridge to the work support. If a greater separation is made, there is no particular benefit obtained and there is a possibility that the adhesivewill be softened too much. If a shorter length of time for impregnation is given, the sur.- face only of the adhesive layer will be activated and the pressure of the presser foot on the welt will not bring the parts operated upon intoy as intimate contact as desirable for this type of work.

As a means to prevent evaporation or other loss of activating liquid from the adhesive layer on the welt, the welt, during its travel from the cartridge 32 to the guide 3B, is surrounded by a at tubular covering secured in heat conducting relation at one end to the worl support in alignment with the guide 3i). Due to the movements of the work support, which as in the machine of the iatent No. 2,271,611 referred to, cooperates with the presser foot to feed the work While clamped, the other end of the tubular covering fll for the welt is spaced slightly from the cartridge so as not to disturb the position of the cartridge.

To distribute the activating agent evenly along the surface of the adhesive layer 3i, the welt is pressed yieldingly against the lower projecting end of the absorbent pad 35 by a light spring l coiled about the sleeve 3d and compressed tween a shoulder at the lower end or" the sleeve and a threaded member d8 slidingly mounted on the sleeve and engaging threads on the cartridge 32. The pressure exerted by the spring is applied to the welt through the closed lower end wall of the cartridge, forcing the welt against the exposed end of the pad.

As the absorbent pad drags along the layer of adhesive on the welt, it may become worn so as to require adjustment. Suitable adiustment is obtained in the position of the pad 'oy rotating the sleeve 36 on the threaded terminal thus forcing the pad through the lower end ci' the sleeve 34 the required amount. By enclosing the welt within the cartridge 32 at the location where the activating liquid is beinQ4 applied, most of the loss of liquid by evaporation is eliminated and consequently, the hazard of re is substantially reduced when inflammable activating liquid o the type referred to is employed. A particular advantage in this respect. is obtained by the arrangement of the slots in the lower end of the cartridge and in the introduction oi activating liquid through the upper end since there is no opportunity for the liquid to run down the cartridge and collect on extended areas or other parts of the machine, thus decreasingf substantially the exposed wetted surfaces from which evaporation may take place. Also, the sewing thread is kept by the covering All from accidental contact with activated adhesive until the 'scivingpoint is reached.

The supply of activating liquid is contained in a reservoir Ell mounted at the top of the machine frame, and is led .to the valve through a piped connection 52. To control the :flow of liquid to the cartridge 32, the valve 52 is constructed with a needle-pointed spring-pressed plunger 5d and an adjusting thumb nut 5S of well-known form to raise and lower the plunger 5d from its seat in the valve. The valve in the position shown in Fig. 3 is closed, shutting oir" the flow of liquid, and when sewing operations are started, the rod 24 of the stopping mechanism is moved forwardly until an adjustable set screw lithreaded in a bracket 60 on the rod presses a flipper 82 pivoted vil() to the outerendof-theplungerll of the valve. Movement of the ipper about itspivot onthe plunger causesa cam portion on the iiipper,

which engages the thumb nut 56, to raise the` plunger from its seat an amount determined'by the position of the thumb nut. To locate the flipper in proper position when the valve is closedthe valve is provided with a buer spring /l having projection 55 engaging a roughened surface of the thumb nut 56 and an end extending into the path of movement of the ilipper. The flipper, when contacting the spring, is held properly to be engaged by the set screw i-l as the machine is started.

Sewing machines of the type above identified ordinarily are heated to facilitate handling wax coated sewing threads. A number of electric-al heating units are provided in the machine frame for this purpose, one of "which for the shuttle indicated at Si in Fig. l. The heat in the machine, thereore, is conducted vfrom the work support to the tubular covering M. which, in the illustrated construction, is composed of copper, to'

been indicated, and a construction embodying the several 'features of the invention having been specifically described, what is claimed is:

l. A. machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive quick drying adhesive containing cellulose to the margin of a shoe outsole, in which a highly volatile activating liquid is employed having, in combination, stitch forming devices, Work clamping means. a guide for directing a welt strip towards the point of operation of the stitch form'- ing devices, a supply of activating liquid, activating liquid applying means located sufficiently in adv-ance of the clamping means to provide a time interval within which the adhesive layer may become impregnated to a substantialdepth while the welt is traveling from the liquid applying means to the clamping means at the normal sew'- ing speed of the machine, andvmeans to prevent escape of liquid evaporated from the adhesive before reaching the clamping means.

2. A' machine for simultaneously sewing' and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which a highly volatile activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the pointv of operation of the stitch forming devices, 'a supply of activating liquid, activating liquid applying means located sufciently in advance of the clamping means. to provide a time interval within which the adhesivelayer may become impregnated to a substantial depth while the welt is traveling from the liquid applying means to the clamping means at the normal sewing speed of the niachine, anda tubular rcovering for the welt between the activating liquid applying means and the clamping means to prevent escape of liquid evaporated from the adhesive and to conduct heat from the machine to the adhesive on the welt.

3. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which a highly volatile activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, a cartridge having slots in its side walls at its lower end through which the welt strip is guided to apply the activating liquid to the adhesive layer suiciently in advance of the clamping means to cause the layer to become impregnated substantially to its full thickness before reaching the clamping means, and an absorbent pad in the cartridge for distributing the activating liquid evenly along the surface of the inactive adhesive as the welt passes through the slots in the cartridge.

4. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which an activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, la cartridge having slots in its side walls through which the welt strip is guided to apply the activating liquid to the adhesive layer suiiiciently in advance of the clamping means to cause the layer to become impregnated substantially to its full thickness before reaching the clamping means, an absorbent pad in the cartridge for distributing the activating liquid along the surface of the inactive adhesive as the welt passes through the slots in the cartridge, and means in the cartridge for pressing the welt strip yieldingly against the pad.

5. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which a highly volatile activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, a conductor for bringing the activating liquid towards the welt strip, means .at the end of the conductor for distributing the liquid over the adhesive layer, and a hollow slotted cartridge through the lower end of which the welt strip passes enclosing the distributing means to reduce evaporation of the liquid at the point of application.

6. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which an activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, a conductor for bringing the activating liquid to the welt strip, means at the end of the conductor for distributing the liquid over the adhesive layer, a hollow slotted cartridge through which the Welt passes enclosing the distributing means to reduce evaporation of the liquid at the point of application, and la spring inside the cartridge f or pressing the slotted end of the cartridge towards the distributing means.

7. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which an activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, a conductor for` bringing activating liquid towards the welt strip, a threaded terminal at the end of the conductor, an adjustable threaded sleeve surrounding the terminal, an absorbent pad in one end of the sleeve to engage the end ci the terminal and arranged to be forced out of the end of the sleeve by engagement with the end of the terminal, and means for yieldingly pressing the adhesive layer on the welt strip against the pad during its passage towards the stitch forming devices of the machine.

8. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which an activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, a conductor for bringing activating liquid towards the Welt strip, a threaded terminal at the end of the conductor, an adjustable threaded sleeve surrounding the terminal, an absorbent pad in one end of the sleeve to engage the end of the terminal and arranged to be forced out of the end of the sleeve by engagement with the end of the terminal, a hollow slotted cartridge slidingly mounted on the sleeve and formed with a closed end wall adjacent the end of the sleeve, and yield ing means for pressing the closed end wall of the cartridge towards the end of the sleeve to cause the projecting absorbent pad to wipe along the adhesive layer as the welt is drawn through the slots in the cartridge.

9. A machine for simultaneously sewing and cementing a Welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which an activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, a conductor for bringing the activating liquid towards the welt strip, means at the end of the conductor for distributing the liquid over the adhesive layer, a hollow slotted cartridge through which the welt strip passes enclosing the distributing means to reduce evaporation vof the liquid at the point of application, and a valve actuated by the machine to shut off the supply of activating liquid from the conductor when the sewing operations are terminated.

10. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole, in which an activating liquid is employed having, in combination, stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, a conductor for bringing the activating liquid towards the welt strip, means at the end of the conductor for distributing the liquid over the adhesive layer, a hollow slotted cartridge through which the welt strip passes enclosing the distributing means to reduce evaporation of the liquid at the point of application, and an adjustable valve for regulat-l ing the flow of activating liquid during sewing and for shutting off the flow of liquid when the sewing operations are terminated.

1l. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive adhesive to the margin of a shoe outsole in which a volatile activating liquid is employed having, in combination, stitch forming devices, means for heating the stitch forming devices, work clamping means, a guide for directing a welt strip towards the point of operation of the stitch forming devices, a supply of activating liquid, a metallic tubular covering for the Welt before entering the Welt guide arranged in heat conducting contact with heated portions of the machine to Volatilize, at least in part, activating liquid drawn into the covering with the Welt, and means arranged in spaced relation to the covering for applying the activating liquid to the adhesive layer on the strip sufficiently in advance of the clamping means to cause the layer to become impregnated in the time taken for the welt to travel through the tubular covering.

12. A machine for simultaneously sewing and cementing a welt strip carrying a layer of inactive quick drying adhesive containing cellulose to the margin of a shoe outsole in which a highly volatile organic activating liquid is employed having, in combination, stitch forming devices, a guide adjacent to the point of operation of the stitch forming devices for directing the welt strip against the shoe, work clamping means at the sewing point formed to compress the Welt strip throughout its width against the shoe, a supply of activating liquid, and activating liquid applying means located suciently in advance of the welt guide and clamping means to provide a time interval of from three to five seconds Within which the adhesive layer may become impregnated to a substantial depth while the welt is traveling from the liquid applying means to the clamping means at the normal sewing speed of the machine.

FRED ASHWORTH.

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