US3341873A - Methods and machines for making goodyear welt shoes - Google Patents

Description

p 1967 s. M|LLE| 3,341,873

METHODS AND MACHINES FOR MAKING GOODYEAR WELT SHOES Filed June 3, 1965 5 SheetsSheet 1 lnven for: Lloyd G. Mfi/er B y 5/5 fltornqy Sept. 19, 1967 L. G. MILLER 3,341,873

METHODS AND MACHINES FOR MAKING GOODYEAR WELT SHOES Filed June 5, 1965 5 Sheets-Sheet 2 P 1967 L. G. MILLER 3,341,873

METHODS AND MACHINES FOR MAKING GOODYEAR WELT SHOES Filed June 5, 1965 5 Sheets-Sheet 3 L. G. MILLER Sept. 19, .1967

METHODS AND MACHINES FOR MAKING GOODYEAR WELT SHOES 5 Sheets-Sheet 4 Filed June 3, 1965 Sept. 19, 1967 1.. G. MILLER 3,341,873

METHODS AND MACHINES FOR MAKING GOODYEAR WELT SHOES Filed June 5, 1965 5 Sheets-Sheet 5 t LQQGO 9 u N WR N Y United States Patent 3,341,873 METHODS AND MAQHINES FOR MAKING GGODYEAR WELT SHGES Lloyd G. Miiler, Beverly, Mass assignor to United Shoe Machinery Corporation, Flemington, N..i., a corporation of New Jersey Filed June 3, 1965, Ser. No. 461,057 Claims. (til. 12-145) ABSTRACT 9F THE DHSCLQSURE A shoe inseam sewing machine and method in which a lasting spur engages the upper in cooperation with the awl and the needle to impart a tension heightwise of the last during the formation of the inseam uniting the upper to a rib on the insole.

This invention relates to improvements in methods and machines for making Goodyear welt shoes and more particularly to the art of assembling such shoes wherein a simplified step of combined sewing and lasting is successfully applicable to a wide range of shoe sizes, materials and styles without essential modification.

It has long been the desire on the part of shoe manufacturers to eliminate the use of metallic fastenings while lasting Goodyear welt and other similar types of shoes. The use of such metallic fastenings is undesirable for several reasons, amongst which are dangers of injury to a wearer of a shoe or to a machine operating on the shoe and to an operators eyes or hands, difiiculty from walking about factory floor areas unavoidably littered with such fastenings, and interference with or damage to the cutting edges of tools coming into contact with such fastenings.

In an eflort to avoid the use of metallic fastenings for lasting Goodyear welt shoes it has, therefore, been proposed to postpone the lasting of such shoes until that time is reached in manufacturing procedures where a thread inseam is to be inserted as a permanent connection between the parts of the shoe. This proposal is particularly attractive by reason of an inherent tendency for the thread inseam to pull heightwise of a last the parts including the upper of a shoe operated upon together by means of a cumulative thread tension as the inseam progresses. However, the ordinary insearning operation is somewhat limited in its ability by itself to provide an adequate and uniform upper pulling action and accordingly attempts have been made heretofore to use supplemental devices, such as upper gripping and lasting jaws acting on the marginal portions of the shoe uppers as the sewing devices form an inseam.

The use of upper gripping and lasting jaws to supplement the upper pulling action of the sewing devices in an inseam sewing machine is disclosed in United States Letters Patent No. 2,155,438, granted Apr. 25, 1939, upon application of A. R. Morrill. While lasting jaws do assist to some extent the upper pulling action of the thread, the full benefit of such jaws is not obtainable because of space limitations in and about the sewing point in that machine. Because of space limitations it has always been necessary to release the grip of the jaws on the margin of an upper during each sewing cycle before each stitch is tightened and set in the shoe parts. Accordingly, there is an opportunity for the marginal portions of the upper, after being released by the jaws, to slip back to their original untensioned positions, where no amount of subsequent tension in the thread alone can produce the desired lasted relation of the upper margin.

Further and more serious difiiculties in the use of upper lasting grippers in an inseam sewing machine also appear to be unavoidable. While preparing an upper for a combined lasting and sewing operation it is necessary for best results to preform its marginal toe and heel portions and, preferably, to secure them in centered relation on a last, so that the edges of the angle opening and the vamp will be located in balanced positions on the last. This is usually done by gathering together the marginal portions of the upper at the toe and heel and by securing them temporarily to the insole, while leaving free marginal portions of the upper at the sides of the insole. In gathering together the toe portions of the upper, particularly in the presence of a toe stiffener and linings, bulky projections are produced, which interfere with the operation of upper lasting grippers. For this reason it is necessary to trim the excess gathered marginal portions of the upper around the toe end of the insole, but when this is done the normal operation of a pair of supplemental upper lasting grippers must be inhibited about the toe of the shoe. Otherwise, during each downward stroke of the grippers, while reaching for a fresh portion of the upper, they will strike the trimmed oh? and gathered edges of the upper margin forcibly, so that a proper sewing position of the shoe will be disturbed and frequently the shoe will be ejected from the machine. Because of the danger of ejecting a shoe from the machine by being struck by upper lasting grippers, mechanism is provided in the Morrill patented machine for rendering the lasting grippers inoperative, while sewing about the pretrimmed shoe toe. When the grippers are rendered inoperative an additional difiiculty arises because in trimming the gathered upper projectons on a lasted shoe toe considerable variation may occur from one shoe to another in the extent to which the trimming has been done and, consequently if the grippers are thrown out of operation and then again rendered operative, at predetermined fixed positions, these positions may not coincide with the actual points at which the trimming has been started and ended. Accordingly, there will most certainly be sections about the trimmed toe area of a shoe where the upper pulling action is improperly effected. Similar difficulties are encountered in sewing heel seats if a sewed-heel-seat shoe is being manufactured.

To avoid the above-noted difiiculties and to provide suitable steps for preparing the essential parts of a Goodyear welt shoe on a last in a manner compatible with a combined inseam sewing and lasting operation, are primary purposes of the present invention, subsidiary purposes also comprising improvements in lasting procedures heretofore performed for pulling heightwise of a last and securing the upper of a shoe in position while inserting an inseam. Still further objects are. to reduce the number of steps required to bring a Goodyear welt shoe upper into final conformity with a last on which it is mounted and to expedite the construction of shoes of this type wherein uppers may be secured in conforming positions on lasts more expeditiously and with the exercise of less skill and ability on the parts of those performing the different preliminary steps.

In accordance with the purposes of the invention, the present method consists in the steps of assembling an upper on a last with the marginal portions of the upper stretched lengthwise of the last bottom, gathering the lasting marginal portions of the upper about at least the toe end of an insole and securing it to the insole temporarily while leaving free the side portions of the upper and successively sewing the free sides and the toe end to the insole and exelting a heightwise tensioning pull on the upper at a point between each completed stitch and the position where the next succeeding stitch is to be formed. In this method the free sides and the toe end portions of the upper are sewed to the insole with the usual continuous thread chain-stitch inseam, while imparting a heightwise pull in addition to that normally exerted on the upper margin during sewing. By so doing the lengthwise stretching tension in the upper margin will be distributed more nearly evenly than has been possible heretofore throughout the inseam and the full benefit of the inseam is employed to pull the upper margin heightwise of the last.

In the preferred form of the invention the use of upper lasting grippers is avoided and the upper is pulled by a pointed lasting spur, such as that disclosed in Patent No. 3,077,844, granted Feb. 19, 1963, upon application of Lloyd G. Miller, especially when equipped with a takeup and thread finger similar to that disclosed in United States Letters Patent No. 3,088,426, granted May 7, 1963, also upon application of Lloyd G. Miller. With the take-up and thread finger of Patent No. 3,088,426 it is possible to apply a stronger than usual upper pulling tension to the thread and no difiiculty is encountered with interference by excessively wide margins of the upper with the sewing thread.

To facilitate the performance of the inseam sewing and lasting machine the invention has for a further object to provide a machine which will more or less overcome the likelihood of failure to detect a condition of improper operation in the machine and to aid the operator of the machine in displacing the shoe from the machine quickly upon the occurrence of such improper operation.

A feature of the invention contributing to the attainment of this object is derived from the use of the upper lasting spur, which so increases the time of engagement of the shoe with the other work penetrating instruments in the machine that it is feasible to bridge over the interval remaining in each sewing cycle, in which the shoe is not supported effectively by utilizing tension in the thread for this purpose. Under these conditions the shoe is immediately ejected by reason of its own weight or by engagement with one of the work penetrating instruments whenever loss of tension in the thread is experienced from any cause.

These and other features of the invention, as hereinafter described and claimed, will readily be understood by those skilled in the art from the following detailed specification taken in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view of a last prepared with a ribbed insole partly broken away and secured to its bottom surface in accordance with a preliminary step of the present invention;

FIG. 2 is a similar view of the same last after having a shoe upper assembled on it with the marginal portion pulled lengthwise over the last;

FIG. 3 is a similar view illustrating the formation of the marginal portions at the toe end of the upper after being gathered together and secured to the insole while leaving the portions of the upper at the sides of the insole free and unattached;

FIG. 4 is a view in side elevation of the upper with the marginal portions gathered together at the toe end of the last and secured to the insole;

FIG. 5 is a fragmentary sectional view looking from the left of a machine arranged for simultaneously sewing and pulling the free marginal portions of the upper with a continuous thread chainstitch inseam;

FIG. 6 is a detailed sectional plan view illustrating the manner of sewing the inseam and simultaneously pulling the free marginal portions of the upper;

FIG. 7 is a sectional detail view of a central part of a shoe on an enlarged scale, illustrating in side elevation the free marginal portions of an upper being pulled into lasted position;

FIG. 8 is a detail view of the shoe illustrated in FIG. 7 but taken from the opposite side to show the manner of pulling the upper heightwise of the last on which it is mounted;

FIG. 9 is a sectional detail view in right side elevation of a welt guide actuating mechanism employed in the machine for sewing and lasting in accordance with the present invention;

FIG. 10 is a sectional detail plan view on an enlarged scale of a sewing and lasting inseam being inserted in a shoe;

FIG. 11 is a sectional view of the shoe being sewn, taken along the line XIXI of FIG. 10;

FIG. 12 is a sectional detail plan view of the sewing and lasting inseam at a later stage of its formation;

FIG. 13 is a sectional view of the shoe being sewn, taken along the line XIII-XIII of FIG. 12; and

FIG. 14 is a time chart of operations in the combined upper sewing and pulling machine.

The shoe illustrated in the drawings is of the Goodyear welt type and is prepared for its fundamental inseam sewing and upper pulling heightwise of a last on which the shoe is supported by no more than four essential preliminary steps, namely:

(1) The provision of a last having mounted on its bottom a ribbed insole,

(2) Assembling and pulling-over the last marginal portions of an upper to stretch it lengthwise of the last, and

(3 and 4) Toe and heel preforming and lasting by gathering and pleating those marginal portions only. Combined inseam sewing and upper pulling operations are performed by the machine of Patent No. 3,077,844, modified somewhat to accomplish the desired results in accommodation with the preliminary steps.

Heretofore, attempts have been made to combine inseam sewing and upper pulling transversely to the line of the inseam in a compatible method for making Goodyear welt shoes. These attcmpts have usually centered about the use of supplementary upper pulling grippers incorporated into the construction of a Goodyear welt inseam sewing machine. The use of upper pulling grippers in an inseam sewing machine is fundamentally inconsistent with the inseam sewing because of the inherent bulkiness of such grippers and the lack of available space in which to mount them for proper operation.

Furthermore, in lasting a shoe upper the marginal portions of the upper around the toe and heel require gathering and pleating in a uniform manner in order to conform the upper with a last on which the shoe parts are assembled and to attach a welt and the upper to the lip or rib of the insole. Upper engaging grippers are unable to accomplish such gathering and pleating action consistently on the marginal portions of the upper because the pleats at the toe and heel increase the effective thickness of the upper. If the toe and heel are prelasted before inserting an inseam, then the upper thickness already is increased and the grippers are unable to be opened sufficiently to receive and grip securely the pleated portions of the upper.

For proper toe and heel lasting operations it is necessary to grip and pull not only the upper but the lining and heavy stiffening or counter materials ordinarily combined with these portions of the upper, so that any lasting grippers heretofore capable of use in an inseam sewing machine are inadequate to comply with requirements for upper pulling about the toe and heel of a shoe. Attempts to avoid this difiiculty by rendering the upper engaging grippers inoperative under manual control about the toe and heel portions of a shoe impose too heavy a burden on the skill of a machine operator and no fully successful automatic mechanism has thus far been developed for relieving the operator of this burden.

It has been found that with the machine of inventors prior patent the marginal portions of the toe and heel of a shoe upper may be prelasted and then the entire upper may be sewn and pulled with a tension directed heightwise of a last on which the upper is mounted, progressively without interruption from one unlasted side to the lasted portion at the toe and from the lasted portion of the toe to the other un'iasted side without affecting adversely the uniformity of heightwise pull applied to the upper, whether the upper after being gathered and pleated is already attached to the insole or not, and no attention is necessary on the part of the operator to change the manner of presenting the shoe to the machine between different lasted and unlasted portions of the upper margin. This is because the machine of inventors prior patent, instead of utilizing upper grippers to provide the supplementary pulling action, depends upon a spur acting to penetrate the upper margin to the exclusion of the other parts of the shoe, directly above the sewing rib on the insole to pull the upper. Thereafter, while the spur retains its penetrating position in the upper a stitch is formed and then the upper is pulled further by the inseam by reason of thread tension into a firmly lasted position. With additional modifications in the prior machine the upper pulling spur may be lowered somewhat closer to the needle to enhance the upper pulling action of the thread and to increase the flexibility of the resulting shoe. Also, the spur may act on the upper margin without regard to its gathered and pleated condition along the toe and heel in the same manner as along the side of the upper margin. Thus, the supplemental pulling action does not interfere with the sewing and is able to release its pull on the upper after each stitch is formed and to reapply its pull before that stitch is tightened with a stitch setting tension.

The improvement in supplemental upper pulling and the increased shoe flexibility result from the use of the spur, illustrated at in the accompanying drawings, on a sewing rib 12 of the insole, indicated at 14 in FIGS. 5, 7 and 11. The insole is mounted on the bottom surface of the last, shown at 16, about which the upper including a lining and stiffeners, indicated at 18, is assembled by the pulling-over operation.

To improve consistently the action of the inseam thread in pulling the upper heightwise and to render the resulting shoe more flexible than has been possible heretofore, the adjusted position of the spur point is such that it exerts its pull at a point between each completed stitch and the position where the next succeeding stitch is to be formed. In entering the upper it grazes the outer corner of the sewing rib 12 on the insole without penetrating it and depresses it away from a perpendicularly upright position, which it ordinarily assumes on the insole (FIG. 1) to an inclined position leaning toward the middle of the insole (FIG. 13). Also, because the upper is pressed into an inclined position by the spur against the upper edge of the sewing rib, the upper being deformed somewhat into tangency with the spur, the penetrating movement of the spur improves the pulling action on the upper to take out any looseness on the last. After penetrating the upper the spur depresses the rib 12 by direct engagement with it and holds it from returning to its upright position until after each stitch is tightened with a stitch setting tension. This inclined position of the rib is thus retained and increased during insertion of the seam, as will be apparent from a comparison between the positions of the parts shown in FIGS. 1 and 13. The inclination of the rib further improves insertion of an inseam comprising a single thread chainstitch, the single thread portion being firmly embedded in the channel formed by the rib at the lowest possible position. In this way the tension of the single thread in tightening the inseam has little or no tendency to draw the rib back into its upright position. Because the insole rib has now assumed an inclined position its stilfening effect on the insole also is greatly reduced, so that the entire shoe construction is substantially more flexible than is found in constructions in which the rib retains its perpendicular position. In addition the spur strikes into the upper and other combined upper parts just above the welt, indicated at 19 to raise them heightwise to their highest possible positions.

Considering further the preliminary steps for preparing the shoe parts for the combined sewing and lasting operations;

1) The manner of mounting the insole 14 on the bottom of the last 16 is illustrated in FIG. 1, with the outer edge of the insole registering with or set back slightly from a line 20 forming a break between the bottom and side surfaces of the last. To secure the insole in position a number of tacks 22 are driven into the last through the insole.

(2) For assembling the upper with the insole on the last, the last is inserted within the upper and is presented to a pulling-over machine having grippers at the toe end and sides, by which the upper is tensioned lengthwise over the last and is adjusted for proper centering around the ankle opening relatively to the last bottom, seven tacks 24 being driven part way through the upper and into the last to hold the lengthwise tension in the upper for further operations. Two of the tacks 24 are driven at the heel end of the upper, one at the toe end and a pair at the sides of the upper near the toe by a machine more fully disclosed in United States Letters Patent No. 2,758,324, granted Apr. 14, 1956 upon application of F. E. Stratton et al.

(3) The toe preforming and lasting operation is accomplished on a power driven toe lasting machine, as shown in United States Letters Patent No. 2,926,367, granted Feb. 14, 1957, upon an application of Andrew J. Gilbride et al. and No. 2,980,931, granted Apr. 25, 1961 upon application of Andrew J. Gilbride.

(4) For preforming and lasting the heel end of the shoe, a heel seat lasting machine such as disclosed in United States Letters Patent No. 2,656,552, granted Oct. 27, 1953 upon application of Ernest L. Butler et al. may be used, especially if the shoe being constructed is of the sewed-heel-seat type. If the shoe is sewed only from heel breast to heel breast, the heel is flat lasted and the same machine may be utilized by trimming ofi any upstanding portion of the upper, counter and lining.

To assist in retaining the sides of the upper firmly in position against possible displacement during the succeeding sewing and upper pulling operation, it may be desirable to secure temporarily the upper to the insole rib at two auxiliary points 26, which are illustrated in FIG. 3 by staples inserted near the edge of the sewing rib on the insole. These staples may be inserted by auxiliary stapling devices during the toe lasting operation and such devices are easily applied to the machines of the Butler et a1. patent.

While the invention is illustrated as utilizing staples for the auxiliary points of upper attachment and tacks to hold the upper temporarily in preformed position on the last, these staples and tacks are shown merely for easy illustration. The pulling-over tacks would be removed in the next succeeding toe and heel prelasting operations on the shoe. Also, it is preferable to dispense entirely with the use of metallic staples and tacks and to employ pressure sensitive or other convenient form of synthetic adhesive for this purpose, application of adhesive at designated areas being less susceptible to convenient illustration than designations of tacks or staples.

In pulling over an upper surrounding a last, as in step (2) and as shown in FIG. 2, a heavy tension is applied to the marginal portions of the upper lengthwise of the insole and last. The excess length of the upper is taken up primarily at the toe end. Fullness of the upper at the toe end and to some extent at the heel end is absorbed in forming ears 28 protruding outwardly beyond the toe and the double side tacks 24 assist the single toe tack in holding the upper at a balanced position on the last, these tacks also enlarging the projection of the ears 28. At the heel end of the upper there is less tendency for the formation of ears, the upper being held more firmly against the heel end of the last and curving less abruptly than at the toe. This is the form the upper assumes after the pulling over operation.

The pulling over points of attachment may well comprise spot applications of thermoplastic cement where freedom from metallic fasteners is desired. If spots of cement are employed for the auxiliary points of attachment, they are deposited on the projecting shoulder of the insole outside the rib, rather than directly on the rib, for best results. Such applications of cement have the additional advantage of fracturing upon exertion of further heightwise pull on the upper during lasting to free the upper for change in position under pulling force.

In preforming lasting the toe and heel ends of the shoe, the fullness of the ears in the upper, stiffener and lining are redistributed by being gathered and pleated in the form shown in FIG. 3. At the toe, the gathering and pleating action is more pronounced where the toe is pointed. At the heel end of the shoe, the gathering and pleating is not so pronounced, except with a sewed-heelseat shoe.

Ordinarily the gathered and pleated upper with stiffeners and linings at the toe and heel ends of the shoe form stiff projections 30. These projections have always offered impediments to further operation on the shoe, so that it has previously been the practice to trim these projections along a dot-dash line 32, shown in FIG. 4, any similar projections at the heel end of a sewed-heel-seat shoe usually being trimmed or flattened by wiper plates to prevent interference with stitch forming devices while inserting an inseam in the shoe. Because the sewing machine utilized in the present invention is modified in accordance with Patent No. 3,077,844, a much greater clearance space is provided in sewing a shoe than is available in other prior sewing and lasting machines. Also, it is helpful to increase the radius of curvature of the work penetrating instruments in the machine a fraction of an inch more than in the machine of Patent No. 3,077,844 to improve further the clearances for the pleated upper projections.

The sewing machine utilized to combine the sewing and side lasting operations in the practice of the present invention is provided with a curved hook needle 34 and a curved awl 36 having a substantially greater radius of curvature than the needle but having its path of curvature tangent with that of the needle along the lowest portions of their paths which intersect the shoe. Cooperating with the needle in forming the inseam are other devices acting in successive sewing cycles and including a looper 38 for laying thread in the hook of the needle after penetrating the shoe, a thread finger 39 for supplying thread between the last formed stitch and the needle as the threaded needle is being retracted from the work, a take-up 40 to tighten each stitch with a setting tension, and a frictional thread tension wheel (not shown). To maintain the shoe in operating position it is held bottom side up against the lower surface of a channel guide 41 at all times during sewing. All of the ewing devices are connected to mechanisms driven by a main sewing shaft 42 (FIG. 9).

These sewing devices are arranged and actuated to secure a continuous and even feed of the work operated upon, the needle and channel guide being mounted on a feed slide to move together in the line of the seam while the awl is mounted on a second slide to enable alternating and overlapping feeding movements to be imparted to the shoe, as disclosed more fully in United States Letters Patent No. 1,971,575, granted Aug. 28, 1934 upon application of A. R. Morrill and No. 3,005,323, granted Sept. 25, 1962 upon application of Lloyd G. Miller.

In starting a new seam the end of the thread is held between a pair of jaws 43 to insure proper formation of the first stitch in the seam. To stiffen the needle against excessive bending, it passes through a needle guide 44 mounted for oscillating movement on a stud 46 also forming a pivot about which the needle oscillates. The upper pulling spur is clamped to the needle guide 44 and is moved by the guide during its penetrating movement to enter the shoe upper and lining before the needle does, and to remain in engagement with the upper until after the needle withdraws to exert suflicient preliminary heightwise pull on the upper as it is penetrated by the spur to force it against the sewing rib 12. To reduce to a minimum any lack in the parts while penetrating the upper the spur engages the outer corner of the rib and bends it toward the middle of the insole. The spur has a further advantage in that it enters the upper of a shoe before the needle and withdraws afterwards, so that the amount of time in which the shoe is supported firmly in position by a work penetrating instrument is substantially greater than otherwise would be. During certain portions of the sewing cycle the shoe is supported in the machine by the needle 34, awl 36 and pulling spur 10 together (FIG. 6) so that a substantially greater support is provided for the shoe and much less strain is imparted to the work penetrating instruments. Consequently the needle is subjected to substantially less stress than usual and seldom requires replacement.

The mechanism for actuating the upper pulling spur 10 is the same as that employed in the machine of inventors Patent No. 3,077,844. The spur being mounted on the needle guide is actuated indirectly from the needle. As the needle is moved toward the shoe the spur engages the upper before the needle enters the welt. This is insured in the present machine by lengthening the spur as much as possible without interfering with the feed of the shoe. The spur after penetrating the upper remains stationary but moves in the direction of feed with the needle as the needle continues to move into the shoe parts, the spur remaining in the upper until after the needle has fully withdrawn with a loop of thread for the next succeeding stitch. As shown in the 3,077,844 patent the spur and needle guide actuating mechanism consists primarily of a locking ball 47 slidingly mounted in the needle guide between recesses in a segment 48 to which the needle 34 is clamped and a relatively stationary member 45 surrounding the needle stud.

After withdrawing from the upper the pull on the upper is reapplied at the opposite side of the stitch formed during its first pull before that stitch is tightened with a stitch setting tension. The pull accordingly is available for each stitch until after that stitch is set.

Referring to the time chart shown in FIG. 14, the curves labeled Needle, Awl, and Lasting Spur show that the needle 34 penetrates the upper of the shoe at a cross mark 49, at about the 37 position in each sewing cycle, and is disengaged from the shoe at a cross mark 50, or 210 in the sewing cycle. Before the needle becomes disengaged from the shoe, the awl 36 penetrates it at a cross mark 52, or about the point in the sewing cycle, and is disengaged from the shoe at the cross mark 54, or about a 350 time in the sewing cycle. The lasting spur 10 being secured to the needle guide 44, the length of time during which the work penetrating instruments engage and support the shoe is increased by approximately 18 beginning at the 19 position of the time chart, as shown by a cross mark 56. During this additional 1 8 between the cross mark 56 for the Lasting Spur curve and the cross mark 49 of the Needle curve, the shoe is held supported securely in a raised position with the insole pressing upwardly against the channel guide 41, and the upper engaging a welt guide 57 (see FIGS. 5 and 9) without any special effort on the part of the operator. The lasting spur disengages the work in each sewing cycle at a 240 time, as indicated by the cross mark 58 on the Lasting Spur curve. In this way, one or another, and at times all three of the work penetrating instruments, as in FIGS. 7 and 8, engage the shoe to hold it in position against the channel and welt guides, leaving the shoe supported by a penetrating instrument throughout each sewing cycle, except for a very short interval where the machine ordinarily comes to rest and a sewn shoe is removed and replaced by a new shoe to be sewn. This interval is between the 350 time in each cycle where the awl disengages the work at the cross mark 54, and the 19" position at the cross mark 56 where the lasting spur again engages the shoe. Between these positions the machine is arranged to sup- 9 port the shoe adequately by tension in the sewing thread produced by timed relationships between the operation of the sewing devices.

To support the shoe by sewing thread tension while no work penetrating instrument engages the shoe (350 to 19), the threaded needle 34, after having withdrawn from the work with a thread loop in its hook, tightens the single thread portion of a loop 60 running to each last formed stitch. During this time, a back feeding movement is imparted to the needle, as illustrated by the curve Needle Feed of FIG. 14, increasing still further tension in the thread. During this time, the awl also is engaging and feeding the shoe, and the channel guide has squeezed the work by rearward movement against the pressure of the locked welt guide, as illustrated in the curves Channel Guide and Welt Guide Lock. Thus, the thread tensioning movement of the needle is rendered effective in partly tightening the loop 60.

The extent to which the threaded needle retracts from the work is indicated by a comparison between the Needle curve and the Take-Up curve. It is apparent from these curves that the take-up stops giving up thread at approximately 215 and the needle continues to tension the thread loop 60 until the 260 position in the cycle is reached. At this time the welt guide is securely locked by mechanism shown in FIG. 9 and the channel guide is in a rearward work squeezing position. Thus, the thread between the needle and the take-up is less than that required by the needle and the tension on the thread is increased while the shoe is held securely from upward movement. Thereafter, there is a dip in the needle poistion to prevent retarding the feed of the shoe by reason of thread tension, as shown between the 295 and the 340 points in the Needle curve, the thread still being held in tightened condition by the needle. It is this relation of the parts and of the thread which is maintained during the interval between the 350 and 19 positions of the machine.

In prior machines, including that disclosed in Patent No. 3,077,844, it is necessary for an operator to present a shoe to the machine, to forcibly raise the shoe and to hold its insole forcibly against the channel guide during insertion of an inseam, thus imposing a continuous effort on the operator and adding to the fatigue encountered during continuous use of the machine. On account of the addition of the spur 10 and the improvement in timed relation of the operating parts, as indicated by the time chart of FIG. 14, in the machine of the present invention, it has been found to be unnecessary for an operator to continue holding the shoe forcibly with an upward pressure against the channel guide. The machine itself now holds the shoe in sewing position effectively without any appreciable effort on the part of the operator except for a minimum guiding force throughout a normal operation on a shoe. Furthermore, less attention is required to be given by the operator for an improper operation on the shoe resulting in loss of thread tension or thread breakage.

This feature of the present invention enables an operator to present a shoe with minimum effort and attention to the sewing point in the machine and whenever loss of thread tension or thread breakage occurs, the shoe is released, so that it falls by gravity or may be ejected by one of the work penetrating instruments from the operating point in the machine, providing a positive signal for the operator to stop the machine. Furthermore, the ability for quick disengagement of the shoe from the point of operation in the machine and stopping the machine without delay by seam of which has been discontinued prematurely as the stitches or otherwise unnecessarily damaged parts of the shoe. For this reason, it is easier to repair shoes, the inthe operator, eliminates insertion of improperly formed result of improper machine operation.

To improve the preliminary pulling action of the spur 10 as it penetrates the upper, stiffener and lining, its sharpened end is formed with a chisel edge 62 (FIG. 11) having a bevel providing an acute angle with the upper. As the point of the spur penetrates the upper parts, the bevel surface aids in tensioning them and exerts pressure on them to displace them from their perpendicular relation to the insole. The needle then penetrates the welt upper and lining and has the thread laid in its hook by the looper 38, a short length of thread between the last formed stitch and the looper having been measured by the thread finger 39, as shown by the Thread Finger curve in FIG. 14. The looper 38 moves in accordance with the Looper curve in that figure. In both the Looper and Take-Up curves certain significant relations in small scale views are shown between the looper, thread finger, and the end of the needle to assist in understanding the looping operation.

Referring more particularly to FIGS. 10 to 13, inclusive, the upper pulling action of the thread will more readily be appreciated. Generally speaking, the insertion of a chainstitch is a two-step operation, first, the drawing of a loop through the work to form a stitch, and second, the drawing of a second loop through the work, also enchaining the second loop through the first loop. In a machine employing a hook needle, the needle ordinarily is retracted from the work a sufiicient distance to tighten the single thread portion of the seam against the opposite side of the work. Each loop carried through the work by the needle at the double thread or chain side of the seam then is tightened applying a stitch setting strain to the previously enchained loop passing through it. In this way, the loop tightening action on the seam is accomplished by cumulatively applied tension increasing along the seam successively and with adequate amount of thread movement from each stitch to the previous one, sometimes to the third or fourth loop previously formed to insure full tightening action. The final tightening action on a series of enchained loops froming the inseam may result from several short movements of the thread, first in one direction to tighten the loops, and then in the other direction to loosen them as the tension may be relaxed, each relaxing movement becoming progressively shorter until equilibrium between friction and loosening is reached with the desired stitch setting tension.

It is for these reasons that the use of an upper pulling spur in a chainstitch inseam sewing machine has been found most practical because it is possible to pull the upper twice at opposite sides of each stitch, both at the positions where a stitch is being formed and where that stitch is being tightened with a setting tension. One pull is exerted on the upper at one side of each stitch as the needle penetrates and retracts from the parts with a loop of thread and the other pull at the other side of the same stitch is exerted as that stitch is being tightened with a stitch setting tension.

Upper pulling grippers can not operate in such close proximity to the sewing devices as is possible with a spur. Thus, the only effect of upper pulling grippers in prior machines has been to present the upper to the sewing point in tensioned relation. The grippers then are required by reason of space limitations to release the upper, causing the full strain of the tensioned upper to be applied to the sewing devices, including the needle.

In the present method utilizing an upper pulling spur no difficulty is encountered in exerting a preliminary tension on the upper heightwise of the last on which the upper is mounted and exerted at a point between the last formed stitch in a seam and the position where the next succeeding stitch is to be formed. In so doing the upper tensioning pull holds the upper at the position where each succeeding stitch is to be formed and also assists the previously completely formed stitch to pull the upper still further with a cumulative tightening action. Accordingly, the marginal portion of the upper may not be drawn immediately into snug engagement with the sewing rib at the position, for instance, where the loop 60 of the last formed stitch intersects the parts, the awl 36 applying the only force tending to hold the upper against the sewing rib. However, the parts being operated upon olTer more resistance to deflection than can be overcome readily by the awl so that the awl is either deflected or the shoe is distorted. Therefore, the loop 60 does not fully tighten the previous stitch and does not draw the upper and insole securely together, there being a gap 64 between them. It is only after the needle 34 again penetrates the shoe as shown in FIG. 12 that the loop 60 of the last formed stitch is drawn snugly with a stitch setting tension into position against the welt, so that the parts are pressed firmly together without leaving any gap 64.

The thread tension exerted to draw the parts firmly together is applied by the take-up in retracting the thread in the loop 60, the loop sliding about the needle as it would about a pulley in tightening that loop. Tightening the thread in loop 60 also applies a tightening action to each previously formed loop 66 to increase tension in the previously formed loop. It is in this manner that cumulative tightening action is applied to the doubled thread onthe chain side of the seam.

Under these conditions the spur is able by assisting in the support of the upper margin against release from its previously held position to cause the upper and welt to be drawn upwardly over the shoulder of the insole from the positions of FIG. 11 to those of FIG. 13, so that the upper and lining are made to conform closely with the angle between a shoulder 68 on the insole and the rib 12, as indicated in FIG. 13. This occurs while the spur 10 still engages the upper and lining and may introduce a temporary horizontal fullness Wrinkle 70 into the upper between the threads passing through the parts and the spur. Such fullness wrinkle, however, is not detrimental to the firm attachment of the parts, but may serve to depress the sewing rib 12 into a further inclined position (FIG. 13) or merely to compress the upper and lining heightwise of the last above the threads in the seam to the same extent as it is stretched over the last below the seam.

After the spur has been retracted the margin of the upper of the seam is permitted to straighten out from wrinkled condition and accordingly the surplus is permitted to expand as shown in FIGS. 7 and 8, so that the marginal portion of the upper projects upwardly higher than it did before being penetrated by the spur. In this way the spacings between perforations 72 formed by the spur and the sewing rib 12 at the inner side of the upper and lining (FIG. 7) are greater than they were before, Also, these perforations are raised above the edge of the welt 19 and are readily visible at the outer side of the shoe, as shown in FIG. 8.

After the inseam has been inserted and the upper pulled into lasted relation with the insole, as described, the inseam may be trimmed in the usual way without encountering any metallic fasteners, so that the edge of the trimming knife is not subject to nicking or dulling action ordinarily encountered by such metallic fastenings. Furthermore, the welt and upper are brought reliably into compact relationship with the insole in a manner not heretofore obtainable. The resulting shoe is not only more flexible, as has been explained above, but also is more durable and less susceptible to deterioration from entry of foreign materials through a loose fitting jloint along the essential inseam.

The nature and scope of the invention and exemplary procedures by which the invention may be practiced together with an improved machine, having been described, what is claimed is:

1. A method of making shoes, comprising the steps of providing a last with an insole secured to its bottom,

assembling an upper on the last with the marginal portions stretched lengthwise of the last bottom,

forming the marginal portions of the upper at the toe end by gathering them together and securing them while leaving portions of the upper free at the sides of the last,

sewing the free sides and the toe end portions to the insole with a continuous thread inseam and while sewing the free sides imparting to the upper a pull directed heightwise of the last applied twice during each sewing cycle and exerted at points on the upper between stitch holes.

'2. A method of making shoes, as in claim 1, in which the pull on the upper is released after each stitch is formed and reapplied before that stitch is tightened with a stitch setting tension.

3. A method of making Goodyear welt shoes, comprising the steps of providing a last having a ribbed insole secured to its bottom,

assembling an upper on the last with the marginal portions of the upper stretched lenghtwise of the last bottom,

forming the marginal portions of the upper at the toe end by gathering them together and securing them to the insole, while leaving free portions of the upper at the sides of the insole,

sewing the free side and toe portions to the insole rib with a continuous thread chainstitch inseam and while sewing the free side portions imparting to the upper at points between stitch holes a pull applied twice during each sewing cycle directed heightwise of the last to confirm the upper with the last.

4. A method of making shoes, as in claim 3, in which heightwise pull is exerted by an upper engaging spur, acting to penetrate the upper, once before each stitch in the seam is inserted and once before the inserted stitch is tightened with a setting tension.

5. A method of making Goodyear welt shoes, comprising the provision of a last having a ribbed insole secured to its bottom,

assembling an upper on the last with the marginal portions of the upper stretched lengthwise of the last bottom,

conforming the marginal portions of the upper at the toe end of the last while leaving free portions of the upper at the sides of the insole, and

sewing the free side and toe portions to the insole rib with a continuous thread chainstitch inseam while imparting to the upper successive pulls heightwise of the last,

one pull being exerted transversely to the line of the inseam at one side of each stitch as that stitch is being inserted and the other pull being exerted transversely to the line of the inseam at the other side of the same stitch as that stitch is being tightened with a setting tension.

6. A shoe inseam sewing machine, having a curved hook work penetrating needle acting to draw loops of thread through parts of a shoe presented in bottom up position and to enchain the loops with each other,

a curved work penetrating awl,

both the needle and the awl being mounted for swinging movement in arcuate paths tangent to each other along their lower portions for engagement with the shoe,

a curved work penetrating spur acting with the needle and awl successively in repeated cycles of operation to engage and to support the shoe against removal from the machine, except fora short interval during each sewing cycle in which all of said penetrating instruments are disengaged,

a take-up cooperating with the needle for applying a tension to the thread during said interval to support the shoe while disengaged by the penetrating instruments and to enable the shoe to be freed for displacement from the paths of the penetrating instruments whenever the tension on the thread is lost.

7. A shoe inseam sewing machine, as in claim 6, in

which all of the work penetrating instruments engage the work 1 3 1 4 together at a certain portion of each sewing cycle.- the shoe includes an upper, an insole mounted on a last 8. A shoe sewing machine, as in claim 6, in which and awelt guided into the inseam, the tension in the thread during the interval of disenthe spur is arranged to penetrate the upper to the exclugagement by the penetrating instruments is applied sion of the insole and welt, and While a loop of thread is retained in the hook of the 5 the needle and awl penetrate all three parts of the shoe. 9 ig il h 1 8 References Cited 0 Whi.ch s oe mseam sewin mac me, as in 6 mm 1n UNITED STATES PATENTS the tension in the thread is applied by the needle after 1,570,067 1/1926 Chapelle 12-145 disengagement from the shoe while the take-up re- 10 1,966,479 7/1934 Bales 12 9'1 mains stationary 3,077,844 2/1963 Mlller 112-35 10. A shoe inseam sewing machine, as in claim 6, in 3130430 4/1964 Kambonan 12 145 which PATRICK D. LAWSON, Primary Examiner.

Claims (1)

1. A METHOD OF MAKING SHOES, COMPRISING THE STEPS OF PROVIDING A LAST WITH AN INSOLE SECURED TO ITS BOTTOM, ASSEMBLING AN UPPER ON THE LAST WITH THE MARGINAL PORTIONS STRETCHED LENGTHWISE OF THE LAST BOTTOM, FORMING THE MARGINAL PORTIONS OF THE UPPER AT THE TOE END BY GATHERING THEM TOGETHER AND SECURING THEM WHILE LEAVING PORTIONS OF THE UPPER FREE AT THE SIDES OF THE LAST, SEWING THE FREE SIDES AND THE TOE END PORTIONS TO THE INSOLE WITH A CONTINUOUS THREAD INSEAM AND WHILE SEWING THE FREE SIDES IMPARTING TO THE UPPER A PULL DIRECTED HEIGHTWISE OF THE LAST APPLIED TWICE DURING EACH SEWING CYCLE AND EXERTED AT POINTS ON THE UPPER BETWEEN STITCH HOLES.

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