US3589320A - Pocket blank sewing machine - Google Patents

Abstract

An automatically operating sewing apparatus having the following combination of coacting elements to accomplish the sewing of a pocket blank: means for feeding into a pickup feed position a workpiece; pickup and transfer means for removing a single workpiece from the pickup feed position and transferring the same to a position for feeding to a sewing machine, including holding means for holding the removed workpiece for feeding said workpiece to the sewing machine; conveyor means to the sewing machine for transporting said workpiece thereto including detaching means for separating from the pickup and transfer means the workpiece held in the feeding position, and means for feeding the workpiece to the sewing machine in response to a demand from said sewing machine, said conveyor means including edge guiding means for guiding the workpiece toward said sewing machine while said workpiece is being conveyed towards the sewing machine; means for initial guiding of the workpiece from said conveyor means into a sewing position; feeding means for said workpiece during sewing operatively interconnected to said sewing machine including workpiece engaging and guiding means operative during said sewing; means for guiding the workpiece during a sewing operation; sewing slowdown and stopping means for said sewing and feeding means responsive to a workpiece position detecting and a sewing control means, including means to disengage means for guiding the workpiece during the sewing operation; positioning means for changing the workpiece to another position and to allow sewing said workpiece in at least one other direction, said positioning means being operatively responsive to the interconnected slowdown and stopping means; conveying means to remove a sewn workpiece from the sewing machine including accelerating means for severing a thread chain holding one workpiece to another; means for removing and stacking said severed workpiece from said conveying means. Employing the above described apparatus, exceptionally trouble free operation, with high production rates are obtained without employing complex constraining devices for the pocket blank and accomplishing the results by relying on free flowing nature of the pocket blank as as controlled by properly devised control circuits.

Description

United States Patent [72] lnventor AubreyG.Beazley El Paso, Tex.

[2 l] Appl. No. 851,303

[22] Filed Aug. 19, 1969 [45] Patented June 29, 1971 [73] Assignee F arah Manufacturing Company, Inc.

El Paso, Tex.

[S4] POCKET BLANK SEWING MACHINE 10 Claims, 22 Drawing Figs.

Primary Examiner-James R. Boler Attorney-Curtis, Morris and Safford ABSTRACT: An automatically operating sewing apparatus having the following combination of coacting elements to accomplish the sewing of a pocket blank: means for feeding into a pickup fe d position a workpiece; pickup and transfer means 7 for removing a single workpiece from the pickup feed position and transferring the same to a position for feeding to a sewing machine, including holding means for holding the removed workpiece for feeding said workpiece to the sewing machine; conveyor means to the sewing machine for transporting said workpiece thereto including detaching means for separating from the pickup and transfer means the workpiece held in the feeding position, and means for feeding the workpiece to the sewing machine in response to a demand from said sewing machine, said conveyor means including edge guiding means for guiding the workpiece toward said sewing machine while said workpiece is being conveyed. towards the sewing machine; means for initial guiding of the workpiece from said conveyor means into a sewing position; feeding means for said workpiece during sewing operatively interconnected to said sewing machine including workpiece engaging and guiding means operative during said sewing; means for guiding the workpiece during a sewing operation; sewing slowdown and stopping means for said sewing and feeding means responsive to a workpiece position detecting and a sewing control means, including means to disengage means for guiding the workpiece during the sewing operation; positioning means for changing the workpiece to another position and to allow sewing said workpiece in at least one other direction, said positioning means being operatively responsive to the interconnected slowdown and stopping means; conveying meansto remove a sewn workpiece from the sewing machine including accelerating means for severing a thread chain holding one workpiece to another; means for removing and stacking said severed workpiece from said conveying means. Employing the above described apparatus, exceptionally trouble free operation, with high production rates are obtained without employing complex constraining devices for the pocket blank and accomplishing the results by relying on free flowing nature of the pocket blank as as controlled by properly devised control circuits.

PATENTEU JUN29 1971 SHEET 02 0F PATENTEB JUN29 19m SHEET 03 OF 15 PATENTEU JUN29197| 3,5 9,320

SHEET 05 0F 15 PATENTED JUN29 ml SHEET 1E 0F ma M. M

PATENTEB JUHZ 9 mm SHEET 15 [1F Qmm tuba:

m Ml Em I QNQ w POCKET BLANK SEWING MACHINE This invention relates to a repetitive sewing machine operation and an apparatus therefor whereby a workpiece is sewn successively along at least two edges thereof and means for effecting the repetitive sewing by workpiece advancing, positioning, separating and removing means; more specifically, this invention relates to a sewing machine in combination with apparatus and means to sew back pocket blanks used in pants whereby this limpid blank is automatically advanced, positioned, sewn, separated, and removed during this operation.

In the production of garments, such as pants, almost endlessly repetitive sewing operations are required for a competitive manufacture of these garments. Thus, for example, in the manufacture of pants, such as pants for men, the back pockets are fashioned from a pocket blank which undergoes a number of manufacturing steps until it is incorporated into the finished pants article.

As part of this operation, and after the back pocket blank has been cut, it is folded, a facing may be sewn on it, and then this blank is stitched along three edges to form a pocket pouch. In sewing along the edges of this blank, at the two bottom corners of this pocket, approximately 90 turns must be made. Moreover, the pocket may not be fashioned as a perfect rectangle, but rather the edges of the pocket may be slightly curved.

A number of steps are performed in the sewing operation of these pocket blanks, and heretofore manual labor has been utilized to produce these semifinished articles. Consequently, the cost component attributable to manual labor in this semifinished article is rather high. Despite the endlessly repetitive nature of each operation and the incentive to reduce the cost of the semifinished article because of the repetitive operation, it has not been possible to do so; and the cost because of the high labor component in this article has remained high.

Previous art attempts to accomplish serial and successive operations on various blanks are, as a general rule, inapplicable, as these attempts have been directed to performing sewing operations on different workpieces which have required an entirely different arrangement of sequential operations. Moreover, conceptually, these different machines are unrelated, as each workpiece, because of the almost endlessly repetitive nature, prevents the utilizing of the machines designed for any other operation. Although, in an isolated context, some of the machines used in performing repetitive sewing operations may appear related because of repetitive sewing operations, upon further analysis, it is evident that the total combination used for each workpiece consists of differently coacting elements, and, hence, each combination is driving towards a different end result. Moreover, the prior art devices have often employed clamps, e.g., frames and belts to constrain a workpiece blank. These constraining devices have required ancillary indexing means. As a result, a multitude of cams, indexing gears, engaging devices which rely upon belts, chains, shafts, etc. have introduced, for these operations, an intolerable mechanical complexity for achieving a simple result.

Therefore, it has been a desideratum in the repetitive sewing operations to achieve a simplified, faultless, trouble-free,

and freely-flowing sequential operation which can be carried out at a high rate of operation with a minimum of manual labor component when acting on a single item.

It has now been found that the actual sewing operation of certain endlessly repetitive steps performed on the same type, or substantially the same type, of workpiece can be accomplished in a superior manner when compared to the best machines heretofore known, or even the most skilled manual labor, by means of a sewing machine when the same is operated in a combination utilizing the freely flowing nature ofa limpid workpiece blank and when the operation is carried out with interrelated means which advance, position for sewing, sew, and remove from the sewing zone the workpiece, i.c. the partially finished back pocket blank.

It has been further found that a novel adhesive tape workpiece transfer device has been especially noteworthy as an element in this combination assuring reliable, demand-originated flow of the limpid blank upon which. the sewing operation is performed. This transfer device provides a simple and uncomplicated means for advancement of imprecisely aligned workpieces.

Still further, it has been found that a novel combination of guide and positioning means in conjunction with the pickup and transfer means enable the advancing of a workpiece to the sewing zone in a trouble-free manner without interference with ,the preceding workpiece while the latter is being sewed. Moreover, it has been found that a combination of rigid guides, in cooperation with actuatable guide devices, operated in conjunction with the sewing machine drive means, presser foot, feed dog and needle provide a unique sequencing device for performing sewing operations having a plurality of approximately turns on a particular material.

Additionally, it has been found that the workpiece stitch chain formed during the sewing operation can easily be broken by a workpiece severing means disclosed herein and the severed workpiece removed after this severing operation in a facile, trouble-free manner.

Various other advantages of this invention will be pointed out or will be apparent from the further discussion of the invention in reference to the drawings.

A smoothly flowing workpiece handling has now been achieved in respect to pants pocket blanks with a machine as further described herein and in reference to the drawings wherein the same elements or elements functioning in equivalent manner have been designated with like identifying numbers and wherein:

FIG. 1 is an isometric view of the novel machine in combination with the advancing, positioning, sewing, and removing means which perform the complete work cycle in the sewing ofa pants back pocket blank;

FIG. 2 is a top view of an adhesive tape transfer device in the combination illustrated in FIG. 1;

FIG. 3 is an end view of the pocket blank conveyor illustrating the pocket blank removal roller for separating the pocket blank from the adhesive transfer device along line 3-3 in FIG.

FIG. 4 is a side view in section of the adhesive tape transfer device and the cooperating lifting bar mechanism along the line 4-4 in FIG. 2;

FIG. Sis a top view ofa sewing table showing the work guiding, positioning, and severing means in the operation of the sewing machine;

FIG. 5a is a section of FIG. 5 along line 5a;

FIG. 6 is a section 6-6 of FIG. 5 and a detailed illustration of the side guide idler roller means in the initial sewing operatron;

FIG. 7 is a section 77 of FIG. 5 and is an end view towards the head of the sewing machine illustrating the guiding means around the sewing machine presser foot;

FIG. 8 is a top view ofthe workpiece removing device;

FIG. 9 shows the left end view of workpiece removing device ofFIG. 8;

FIG. 10 is a section l010 of FIG. 8 and illustrates the stacking table; and

FIG. 11 is a section line 11-11 and illustrates the standing table with the guide means therefor;

FIG. I2 is a schematic diagram illustrating the manner in which FIGS. through 121' should be arranged to form a complete circuit diagram;

FIGS. 12a through I2i together comprise a circuit diagram illustrating the operation of the machine shown in FIG. 1.

GENERAL DISCUSSION OF THE APPARATUS In reference to FIG. I, the apparatus illustrated therein con,- sists ofa belt conveyor I upon which the precut and prefolded fabric blank 2 is placed. This blank is also illustrated in FIG. 2 and in FIG. 8 in finished form. As the bundle of blanks is advanced, each blank, either individually or one resting on top of another, is urged onto lifting bar 3 by means of conveyor belts 4. The lifting bar is actuated when the adhesive tape pickup and transfer device 5 with arm 6 has swung 90 in a position in which arm 6 is directly above lifting bar 3. In reference to FIG. 2, upon being lifted by the lifting bar 3, the blank 2 attaches to an adhesive tape 7 which is pressed to an adhering contact with the fabric blank when the lifting bar with the pocket blank on top of it moves against the same adhesive tape. The adhesive tape transfer device is actuated when the pulley 12 removes the blank being held over the roller conveyors 57a Photocell 8, when it senses no blank in the path of an actuating lamp 9, advances the conveyor belts 4 to keep a supply of blanks on the lifting bar 3.

After the adhesive pickup of the blank by the pickup device, this blank is swung 90 clockwise with the blank securely dangling from the adhesive tape and transferred over to an input conveyor 57a. Thus, this blank is held over continuously rotating and sprocketand chain-interlinked conveyor rollers 10 forming the input conveyor 570.

When the sewing machine 11 is about ready to receive the next blank, a puller wheel 12 is actuated, and when the puller wheel 12 slightly engages the fabric blank 2, a conveyor roller 10a detaches the blank from the adhesive tape 7 and feeds it along an input path on conveyor 57a.

As the conveyor rollers transport the limpid fabric blank 2 towards the sewing machine 11, i.e. towards the input side thereof, a guide rail 13, on the surface of the input conveyor 57a which rail is at a diverging angle to an imaginary line perpendicular to axis of rotation when viewed towards the sewing machine 11, guides the fabric towards the sewing machine as the conveyor rollers 10 urge the blank snuggly against the rail. The length of the conveyor and the rotating velocity of the rol lers can be appropriately adjusted if needed.

A side guide 14, oriented vertically on a highly polished sewing table 15, is placed again at a slight angle from that defined by a normal feed direction of the sewing machine, which, in this instance sews straight. The side guide 14 urges the fabric blank 2 being sewn away from the straight line and away from the sewing machine head 111. This gentle urging aids in keeping the stitch pattern at a uniform distance from the edge ofthe blank.

However, an additional guide means is required because, in practice, the guiding action favors holding the pocket against the output side of the side guide 14 more than against the input side of the side guide 14, and as a consequence of the sewing machine feed dogs 112 being located adjacent to the output side of the guide. It was found that if a drag were introduced on the limpid fabric blank 2 on the input side of the side guide, the proper feeding was achieved. A drag of the necessary kind is obtained by a drag roller 115, such as illustrated in FIG. 1, Other equivalent means but which are less preferred are rollers, belts, or other friction devices.

In addition to the previously discussed guide means consisting of guide rail 13, side guide 14, and drag roller 115, a further guide means is needed, it is conveniently in the form of an idler roller 16. Its axis of rotation is askew to the perpendicular axis of rotation of the next to last conveyor roller 10b on the input conveyor 570. A brief explanation is as follows: as the sewing machine presser foot 113 comes down on the incoming and unsewed blank 2, this idler wheel 16 makes a low pressure contact on the trailing edge of the incoming blank 2 by pressing it against the conveyor roller 100. This action causes a sidewise urging of the blank and acts as a necessary guiding hand" during the first few critical stitches. After these stitches, the idler wheel 16 is retracted and the subsequent sewing of the blank is accomplished without the aid of this idler wheel 16.

The actual sewing is carried out by lowering the presser foot 113 on the incoming blank and effecting the continuous guiding of the pocket blank 2 by the side guide 14 and drag roller 115. As the first stitch passes along the first, longer side of the blank and is nearing its end, the photocell 19 sensing the end of the blank slows down rapidly the sewing machine for the last few stitches on that side so that the machine can be prepared for controlled stopping in a needle-down" position when photocell 20 senses the end of a blank. When the last photocell stops the machine in the needle-down position, the presser foot 113 is raised.

A demand for a new blank is signalled by a photocell 19 when it senses no interruption by a sewn blank after having accounted for the previous two stitching passes.

This slowing down is needed because the machine cannot be stopped accurately in the needle-down position while it is running at its conventional stitching speed. This slowed down speed of sewing is called inching speed hereafter. Thus, as the machine is running at inching speed, the photocell 20 detects the end of the blank (bottom of pocket) and stops the machine.

The needle 21 is now at an equal distance from the edge of the pocket blank at the side and bottom of this blank. At this time, the sewing machine presser foot 113 and the drag wheel 115 lifts. The blank 2 is now free from all means engaging the same save for the needle 21 which is piercing its corner.

At this juncture, a pocket turner rod 22 having an umbrella lip extension 222 on a sliding block 221 is actuated causing the pocket blank 2 to rotate pivoting the blank on the needle 21 in its down position. The side guide means against which the pocket blank is urged has a semicircular segment space 142. Upon turning the blank 2, this segment space 142 allows the necessary clearance for a pocket blanks corner.

The sewing sequence previously explained is repeated as the sewing machine 11 sews along the bottom (which is about one-third of the distance along the side) and the other side of the pocket, the pocket turner rod 22 effecting the second 90 change of the pocket at the next corner. The control means which sequence and permit this operation are explained further herein.

As the pocket blank is sewn along the last side, the sewing operation instead of signaling another turn continues because a new pocket blank is already in place ready to be sewn. This sequence again is achieved with the timing devices provided herein and as discussed with respect to the circuit control. However, two items of consequence must be met for effective handling of the incoming blank. First, the machine should continue sewing at its high sewing speed, thus forming a thread chain 58. Second, because of the geometry of the formed blanks, the incoming blank and the finished pocket blank overlap and would engage each other if it were not prevented in accordance with the invention herein.

It is necessary to prevent this overlap as the finished pocket would drastically alter the sewing pattern for the incoming blank. Thus, to prevent the trailing edge of the finished blank from engaging the leading edge of the new pocket, a pocket corner lifter cylinder 23 is projected vertically, for example by suitable means, such as a pneumatically activated rod or cylinder 231, just before the new pocket would have made contact.

As soon as the new blank is trapped by the sewing machine presser foot 113, the rod 231 is retracted promptly. The finished blank is still attached to the blank being sewn by thread chain 58.

In order to separate these blanks, the thread chain 58 must be broken. it is accomplished by having a conveyor roller 10c geared to run several times faster than the other rollers and activating a double wheeled forcing roller 24 and to press against the rapidly rotating roller when the proper distance is observed by a photocell 56. This action accelerates the pocket and breaks the thread chain. As the finished blank interrupts the light beam of photocell 25 at the end of the conveyor, it activates a stacking arrangement consisting of a stacking gridiron 26 which fits between the roller conveyors 10. A pinion 27 is activated such as by pneumatic means illustrated by a cylinder 28 pushing a suitable rack 29. A motor 30 which may be of the same make as 39 (described hereinafter) with a pinion 31a and rack 31b drops the receiving table 32 on each transfer of a new blank for a distance equivalent to the thickness ofa blank.

As the pneumatic system is based on directly piped fluid under pressure, as this system is controlled by appropriate solenoid operated valves placed in the fluid lines and as this system does not perform independent functions in the present device, the piping for this system has not been shown. How ever, the circuit diagram illustrated herein show the necessary valves which are activated by the appropriate circuit elements.

A more thorough discussion of the various cooperating elements of the invention will now follow in conjunction with the further amplification of the subject matter disclosed in the drawings depicting each ofthe elements ofthe combination.

BELT C'ONVE'VOR in reference to FIGS. l and 2, the belt conveyor l, which advances the fanned out pocket blanks, has three V'formed belts d, as the conveying means. These belts are trained around pulleys on shafts do and db either of which can be driven by a motor. A suitable motor is the same as 39 used in the base ofthe pickup and transfer device 5.

It has been found useful to have the belts slightly recessed but still protruding above a plane formed by the surface of the conveyor table elements dc. At the end of belt conveyor, abutting and overlapping the right-hand or input-side of con veyor structure is a U-shaped combination guide-table dd,

in which the two legs are pointing away from conveyor F570 and which has upturned edges de at both sides. These edges de are tapering to become level at the table portion of the guide table dd, i.e. at the end abutting or proximate the input conveyor 57a. The table end dd of the table-guide if made of the same piece of metal is polished and curved slightly downwardly towards the rollers ill to minimize the dragging friction of the pocket blank 2 when it is pulled over the guide table dd and onto the rollers llll. However, if the table portion of the guide is made ofa separate piece it curves downwardly towards the guide-table dd as well as towards the rollers lll overlapping slightly the last.

In order to provide sufficient space between the table elements dc and the belts d for the lifting bar 3, the end portion of guide table dd is made sufficiently narrow to accommodate the lifting bar El. Further, the shaft db is placed slightly below the guide table element dd to disengage the front part of the pocket blank 2, before the blank is urged further onto the guidetable dd and over the lifting bar 3, by the conveyor belts d. The guide-table dd may have the downwardly curving portion of it which is overlapping the input conveyor 57a made as a separate piece.

in H6. l, the box lllll placed longitudinally next to the belt conveyor ll contains the electrical circuit elements for the conveyor l, the pickup and transfer device 5, and additional pneumatic conduits and valves used with these devices as further described herein. The other electrical circuit elements as well as the pneumatic devices are enclosed in the box identified in Fl G. l as ill/'1 and placed alongside the output conveyor 57b.

lPllClfUP AND TRANSFER DE' /lClE in reference to FIG. 2, the adhesive tape pickup and transfer device 5 will now be discussed as it is used for placing the pocket blank 2 on the input conveyor 57a with the aid of the lifting bar El.

The pickup of the pocket blank and transfer ofit is effected bythe transfer device 5 (hence, a pickup and transfer device) consisting of an upper tape reel 33 which is free to rotate around an axis Zld of the transfer device 5. A lower wheel 35 rotates around axis 3d. The adhesive tape '7 is unwound in small increments or continuously at very low rate from the upper tape reel Illl by winding it on lower tape reel 35 which is driven by means of a motor 38 through a very slowly turning gear train El? driving the reel with belt 36.

As previously discussed, the pickup and transfer arm 6 of the transfer device fl rotates through in a clockwise and counterclockwise direction by means ofa motor fill in the base of this device.

This motor is appropriately actuated by a signal from the puller wheel 12 when the puller wheel l2 removes the previous blank. This blank is heldby the pickup and transfer arm 6. The adhesive tape 7 is sufficiently sticky to hold the blank over the conveyor 57a while the rollers rotate at full speed.

Upon actuating the motor 39, it swings, counterclockwise, the pickup and transfer arm 6 to a predetermined position over the lifting bar ll over which the motor 39 is automatically stopped. The appropriate stop position is determined by a counterclockwise limiting switch d ll riding on a raised counterclockwise limiting cam dl fixedly and nonrotatingly attached to a shaft d5 holding the pickup and transfer device 5. The switch d ll is deactivated by a depression in the cam at the end of the swing. When the counterclockwise rotation stops, the lifting bar 3 is actuated. This bar is covered with an elastomer, such as sponge rubber ddZ, and it lifts upwardly the several layers of the fanned out pocket blanks by means of one or two lifting bar cylinders such as the illustrated single cylinder dd guided by rods ddll, The cylinder, upon retraction, activates the motor 39, and it returns the arm 6 over the conveyor rollers llll with the motion being stopped by a clockwise limit switch d2 activated by a clockwise cam d3 and affixed nonrotatingly to a sleave and in turn tothe shaft, the same as cam dl. These two switches 40 and 4-2 are affixed to a housing d'll which rotates around the shaft and is driven by motor 39. These switches make contact when riding on a raised cam. Of course, these same switches may also make contact when riding on a cam depression.

The motor 39 which drives the pickup and transfer as sembly is attached to a shaft 45 at the base of a pedestal 46 housing the shaft d5. The respective positions of the device 5 are illustrated in FIG. 2 by the dashed lines. This motor is reversible, and in cooperation with switches 40 and 42 turns 90 in either direction. The motor 39 has substantially no coasting characteristics, i.e., it can be stopped in a predeter' mined position with an error of about :1 .5 angular degrees. A representative motor is SSSllPlRC available from Superior Electric Company, New Britain, Connecticut.

The adhesive tape 7 is carefully guided onto the free riding guide pulleys d7 disposed vertically to the line of travel of the tape and then, by imparting a 90 twist, the tape is guided over a rimless but crowned guide pulley dd which has its rotating shaft affixed to the pickup transfer arm 6 about perpendicular to the axis of rotation of the conveyor pulleys and with the lower edge of the pulley dfl protruding below the arm 6. The positioning of the respective tape holding and guiding elements is on a line through the middle of the perpendicularly transverse axis of pulley 48, the middle of longitudinal axes of pulleys d7, and the middle of the axes on which the tape reels 33 and 36 are rotating, thus giving the best operating characteristics for keeping the tape operating smoothly and without overriding. Generally, the tape 7 is advanced only during the counterclockwise swing of arm 6 by an appropriate increment.

Experience has shown that it is sufiicient to advance the tape by about 1/32 inch during this swing. As the motor 38 is geared to rotate the tape advancing reel very slowly, it may be run without interruption during the operation of the machine, or it may be stopped for a given period during each cycle. The upper housing d9 of the pickup and transfer unit including the motor Ell oscillates with motor 39 when the last drives the central shaft d5.

FIG. 3 shows an end view of the pocket blank conveyor 57a with a conveyor roller 10 and the adhesive tape 7 holding a pocket blank 2 which is removed from the tape 7 when the puller wheel l2 is actuated by the pneumatically driven cylinder 50, spring loaded to reside in the up position. Once detached, the blank travels towards the sewing machine on the input conveyor 57a.

edges of the pocket blanks 2 (bottom of pocket) are resting on the lifting bar 3 in the depicted orientation. As different thickness of the pocket blanks are encountered, such as when material of different thickness is used or when a facing cloth is present on the inside of the pocket blank, it makes the stack or bundle uneven. Hence, this depicted lifting action and orientation of the blanks is needed for the successful operation of the machine. For this reason also, the pickup and transfer device 5 is considerably simpler and easier to operate than a single piece pickup device, such as illustrated in US Pat. No. 3,386,396, June 4, 1968. Of course, the operation of the lifting bar 3 and the pickup and transfer device 5 is interrelated and it is further explained in detail in the section dealing with the control circuit. However, equivalent lifting means in place of the pneumatic cylinders 44 may be employed, such as cams, racks and pinions, wheels connected through a pitman lifting the bar, etc. Similarly, the tape drive mechanism may be provided with a ratchet mechanism and keyed to the 90 oscillating motion of the drive shaft 45 as provided by gears coupled to the motor 39.

WO RKPIECE GUIDING, POSITIONING, SEWING, AND SEVERING MEANS Turning now to a more detailed discussion of the sewing operation and the proper positioning of the workpiece, i.e., the back pocket blank, FIG. 5 depicts a top view of this subeombination of elements.

First, the sewing machine II which is employed is of the conventional type, such as Singer 28! or a similar machine in which sewing walks the fabric through the machine to generate a stitch pattern by the use of feed dogs. However, various modifications are employed in the operation of this machine in respect to the fabric guide means.

A. GUIDE MEANS ASSOCIATES WITH CONVEYOR 57a Thus, after the pocket blank 2. has been detached from the adhesive tape, this blank 2 is guided by the conveyor rollers (which are drivlngly connected by chain belts, or gears to each other and to a motor not shown and generally run continw ously). As the blank moves towards the input side of the sowlng machine ll, it is urged against a guide rail l3. As previously explained, the guide rail i3 is at an angle of about 2 to 3 but preferably 2.5 angular degrees to a line perpendicular to the rotating axis ofthe rollers 10. Of course, the angle may be varied. in turn, the line perpendicular to the rotating axis of c the conveyor rollers 10 is directed at a slight angle, i.o. on the same order towards the feed dog, he. at an angle opposite from that of the side guide id and about the same order of magnitude as for rail 13.

A pneumatic cylinder (not shown) may be provided on the input side ofthe conveyor 57a attached to the guide rail id for vibrating slightly the conveying mechanism in the event the llmpid fabric is stuck or is not advanced satisfactorily.

As previously discussed, for convenient handling as well as achieving proper timing sequence, an input angle of the input side conveyor 57:! may be selected which is generally suitable. Moreover, the rate at which the conveyor rollers id are rotated as well as the length of the conveyor, is. the total number of rollers, may be selected to provide for the best operating conditions.

The advantages accruing by the use of guide rail i3 will now be set forth because the operation oi the guide rail has not been explained above. Fist, by employing the guide rail iii, the fabric blank 2 does not have to be placed in a precise manner on the rollers; secondly, it need not be so placed and than gripped with top and bottom bolts as to insure immediate alignment. Moreover, as a consequence of this gently varying alignment, the blanks resting in a stack or bundle on the belt conveyor 1 can be placed on the conveyor rolls id in mis= aligned positions. As mentioned before, this element with other elements in combination renders the present device considerably more simple, relatively speaking, from a device such as disclosed in US. Pat. No. 3,386,396.

B. POSITIONING AND GUIDE MEANS ASSOCIATED WITH SEWING MACHINE DURING SEWING Referring to F I05. 1, 5, 6 and 7, the incoming back pocket blank 2 after leaving the side guide rail 13, which may also be formed as an angle iron with one leg of the angle as an umbrel la over the conveyor rollers 10, proceeds unto the sewing table 15. This table is a highly polished metal plate with three downcurving edges, except for the edge towards the machine which is level with the sewing machine work bed 11a; this table 15 has a stationary side guide 14 positioned on the top of it. Preceding this side guide 14 is a catch hood 52 which is curved upwardly towards the rollers 10 from which it receives the incoming blank. This hood 52 is in the form of a segment from a flat disc with the edge towards the machine tapering downwardly and a flat central plane of the disc being the upper surface of the catch hood 52 the curved portion of the disc facing downwardly towards the table 15.

The function of the hood 52 is to prevent the upturning of corners of a new blank being received on the sewing table 15 or when turning on this table 15 the blank 2 through a 90 angle at the two corners of the blank.

As the outgoing and sewn blank leaves the table 15 after the sewing operation, the geometry of the particular blanks may be such as to overlap at the trailing corner away from the needle 2i before sewing can begin on the new blank. Forthis purpose, a pocket corner lifter 23 is provided which is activated by sensing of the incoming blank by the photocell 19. This lifter rod 23 is activated by a pneumatic means such as cylinder 231 through a solenoid valve appropriately interconnected to the control circuit as further explained herein. The lifter rod 23 is retracted immediately when a properly programmed signal is received, i.e. when the new blank is trapped for sewing by the sewing machine presser foot 113.

The means effecting a trapping of an incoming blank cooperate as follows: After the new blank goes under the hood 52, the roller drag 115, which is canted at about -l0 angular degrees towards the line defined by the sewing machine when stitching, engagesthe blank.

The roller drag wheel ll5'and its assembly is illustrated in FIG. 5 and in cross section thereof in FIG. 5a in more detail. The support axis a upon which the roller rotates and is pivoted for disengagement from a blank is shown as it rests on a support I151; beyond the side guide 14 on the sewing machine ll table. A fulcrum arm 1150 projecting below the support axis 115a of the roller drag wheel provides a surface upon which a rod from a pneumatic cylinder 115d extends to overcome the spring 115a which normally holds the drag wheel 115 down. The spring 115m is adjusted, by appropriate means such as a screw and/or eyebolt attached to the upper arm 1115f of the housing, for proper tensioning and, thus a variable drag effect by wheel 115. The roller drag wheel H5 is activated by the means further explained in the description pertaining to the electrical circuits. For the understanding of the mechanical operation, it suffices to mention that the roller drag 115 is lifted when the presser foot 113 is lifted for pivoting the blank about the sewing machine needle 2i. This roller drag Hi5 can be a knurled roller, wheel, or a friction type device, and adjusting its drag angle with respect to the direction of pocket travel will optimize the guiding characteristics. The drag roller 115 is found to be especially useful as the output side 1st of the side guide is is adjacent to the sewing machine feed dogs I12, and the added drag induces the pocket to fit snugly against the side guide 14 preventing the feed dogs to move the pocket away from the guide. In addition, this drag coacts with the action exerted by the feed dogs 112, urging the blank against the side guide M which is at a slight angle away from the parallel line to which the feed dog would urge the blank if the same were not restricted by the side guide to (which is conveniently in the form of a polished metal surface).

Claims (23)

1. An automatically operating sewing apparatus including a sewing machine in combination comprising means for feeding into a pickup feed position a workpiece; pickup and transfer means for removing a single workpiece from the pickup feed position and operatively interconnected therewith, and for transferring the same to a position for feeding to a sewing machine, including holding means for holding the removed workpiece for feeding said workpiece to the sewing machine; conveyor means to the sewing machine for transporting said workpiece thereto including detaching means for separating from the pickup and transfer means the workpiece held for feeding to the sewing machine, and means for feeding the workpiece to the sewing machine in response to a demand from said sewing machine, said conveyor means including edge guiding means for guiDing the workpiece toward said sewing machine while said workpiece is being conveyed towards the sewing machine; means for initial guiding of the workpiece from said conveyor means into a sewing position; feeding means for said workpiece during sewing, operatively interconnected to said sewing machine including workpiece engaging and guiding means operative during said sewing; means for guiding the workpiece during a sewing operation; means for sewing slowdown and stopping operatively interconnected to said sewing machine and the last-mentioned feeding means and responsive to a workpiece position detecting and a sewing control means, including means to disengage said means for engaging and guiding the workpiece during the sewing operation; positioning means for changing the workpiece to another position and to allow sewing said workpiece in at least one other direction, said positioning means being operatively interconnected and responsive to the stopping means; means for continuing sewing the last seam operatively interconnected to said positioning means, means for initial guiding of said workpiece, and means for slowing down and stopping whereby said positioning slowing down means are rendered inoperative during the sewing of said last seam; conveying means to remove a sewn workpiece from the sewing machine, including accelerating means for severing a thread chain holding one workpiece to another; means for removing and stacking said severed workpiece from said conveying means.

2. The automatically operating sewing apparatus according to claim 1 and wherein the means for initial guiding said workpiece into a sewing position include means for urging the workpiece for several stitches against the means for guiding the workpiece during the sewing operation, means for preventing the upturning of an edge of said workpiece, and means for lifting a preceding workpiece.

2. means for pickup and transfer from said pickup feed position of the single workpiece projected upwardly including a. means for adhesively securing the single workpiece to said pickup and transfer device, b. means for separating said adhesively secured workpiece from other workpieces in said pickup feed position, c. means for transferring for a predetermined distance said single workpiece for conveyance of said workpiece to the sewing machine upon demand from said sewing machine, d. means for holding said workpiece in a transferred position until said demand, e. means for severing said adhesively held workpiece from said pickup and transfer means operatively interconnected with means signaling a demand by said sewing machine, and f. means operatively interconnected with said pickup and transfer means to cause said pickup and transfer means to repeat a workpiece pickup cycle after a removal of a workpiece from said pickup and transfer means, said pickup and transfer means being operatively interconnected to said means for projecting upwardly said workpiece in said means for feeding said workpiece;

3. means for conveying said adhesively detached workpiece to said sewing machine, including means for guiding said workpiece by abuttingly urging the workpiece against an edge guide means which is oriented in a converging, axially longitudinal relationship with said means for conveying said workpiece, said means for conveying having its longitudinal axis positioned in a predetermined location in respect to the sewing direction of said sewing machine; 4, means for initial guiding of the workpiece into a sewing position from said means for conveying said workpiece, including a. means for sidewise guiding of said workpiece, operatively interconnected with means for sensing an approach of said workpiece to said sewing position, b. means operatively interconnected with means for determining an approach of last seam being sewn on a preceding workpiece, c. means for lifting a corner of said preceding workpiece, d. means for disengaging means for guiding preceding workpiece during sewing, e. means for engaging said workpiece with said means for conveying said workpiece whereby the workpiece is placed in a proper relationship to said sewing machine for initial sewinG of said workpiece, and f. stationary umbrella means for preventing the uplifting of a workpiece corner;

3. The automatically operating sewing apparatus according to claim 1, and wherein the means for guiding said workpiece during the sewing operation include sewing machine operated means for exerting a sidewise drag on said workpiece, against a stationary side guide means for said workpiece.

4. The automatically operating sewing apparatus according to claim 1 wherein the workpiece engaging means operative during sewing include a drag means engaging the workpiece on a surface thereof during the sewing operation.

5. The automatically operating sewing apparatus according to claim 4 wherein the drag means are disengaged responsive to the sewing stopping means.

5. means for sewing said workpiece;

6. means for feeding said workpiece during said sewing, operatively interconnected with said sewing machine during sewing, including a. means for engaging said workpiece with said sewing machine, and b. means for maintaining the workpiece in a sewing engagement with said sewing machine operative during said sewing;

6. The automatically operating sewing apparatus according to claim 1, wherein the means for sewing slowdown and stopping include means to sense the end of the workpiece and a stitching line and to vary the stitching rate responsive thereto by engaging the sewing slowdown means and stopping means to position in a predetermined manner the sewing means in a ''''needle down'''' position and a ''''presser foot up'''' position.

7. The automatically operating sewing apparatus according to claim 1, wherein the means for feeding into a pick up position said workpiece holds there at least one workpiece over a vertically moving lifting means for urging said workpiece upwardly for removing a single workpiece by said pickup means responsively to a demand from the sewing means.

7. stationary means for guiding the workpiece during said sewing;

8. means for slowing down said sewing and feeding means operatively interconnected and responsive to a means for workpiece position detecting, including a. first means for sensing an end of said workpiece, operatively interconnected to a sewing machine drive slow down means, and b. means for shifting said sewing machine to a slower stitching speed operatively interconnected to said first means for sensing an end of seam and said sewing machine drive means;

8. The automatically operating sewing apparatus according to claim 1, wherein the pickup and transfer means for removing from the pickup feed position a single workpiece comprises: first means for holding a supply of adhesive tape, second means for holding an advanced adhesive tape, said first and second holding means being located on a common axis; means for guiding said adhesive tape from said first means over an end roller positioned on an arm which extends outwardly from said first and second holding means; means for oscillatingly rotating said arm between workpiece pickup position and transfer position and meaNs for holding said arm with the workpiece being held to the adhesive tape in position for feeding said workpiece to the sewing machine.

9. The automatically operating sewing apparatus according to claim 8 including the pickup and transfer means for removing from the pickup feed position a single workpiece and wherein the supply of adhesive tape is held in a reel, and wherein means for advancing said adhesive tape consists of an incrementally driven reel, the means for guiding the adhesive tape over the roller consists of two rollers axially aligned with the reels, one roller each for taking from and guiding the tape onto said reels respectively, said end roller over which said tape is guided is crowned and aligned in its longitudinal axial midpoint with said reels and said guide rollers, and the longitudinal axial direction between the guide rollers and the end roller is perpendicular and wherein the means for oscillatingly rotating said arm with the end roller is controlled by a clockwise and a counterclockwise limiting switch riding on a cam, said cam being on a shaft, and wherein said shaft supports said reels, arm, the guide means, and cams and is activated by driving means which oscillatingly rotates the said shaft between two positions at which the arm comes to rest.

9. means for stopping said feeding means including a. second means for sensing the end of said workpiece, operatively interconnected to, b. means for positioning and stopping said sewing machine with a sewing machine needle in a ''''down'''' position, operatively interconnected to said sewing machine drive means, and c. means for disengaging said feeding and guiding means, operatively interconnected to said means for positioning and stopping said sewing machine;

10. means for positioning said workpiece for sewing said workpiece in at least one other direction from that of a preceding sewing direction, including a. means for pivoting said workpiece around the needle for a predetermined distance operatively interconnected to said means for feeding said workpiece during sewing, the first and second means for sensing the end of said workpiece and the means for sewing said workpiece; b. means for reengaging said means for feeding and guiding said workpiece, and c. means for reactivating sewing means after completion of said workpiece positioning means;

10. An automatically operating sewing apparatus including a sewing machine, in combination comprising:

11. means for activating said means for positioning said workpiece for sewing said workpiece whereby a predetermined positioning sequence is achieved;

12. means for deactivating said means for positioning said workpiece whereby the predetermined positioning sequence is terminated including a. means for continuing sewing after the sensing of the end of said workpiece by the first and second workpiece end sensing means, b. means for keeping engaged said feeding means, and c. means for activating said means for initial guiding of said workpiece for receiving the next workpiece;

13. Conveying means to remove a sewn workpiece from said sewing machine including a. means to detect the conveyance of said sewn workpiece, b. a partial, rapid conveying section as part of said conveying means whereby a faster conveying is effected in relationship to the conveying rate of the rest of said conveying means, c. engagement means for severing said workpiece whereby the workpiece is accelerated between said engagement means and said partial, rapid conveying section, thereby severing a thread chain joining said sewn workpiece with a workpiece being sewn; and d. edge guide means for further conveying said workpiece,

14. means for removing and stacking said severed workpiece from said conveying means including a. means for detecting the presence of said severed workpiece, b. means for activating a removal rack to pivot the same approximately 180* in a direction perpendicularly away from the conveying means, c. means for deactivating said means for detecting the presence of said severed workpiece, d. means for receiving the workpiece on said pivoted removal rack whereby said receiving means are lowered progressively upon stacking each workpiecE on the same, e. means for returning said removal rack to its original position and, f. means for activating the means for detecting the presence of the severed workpiece;

15. means for monitoring the correct operation of said automatically operating sewing apparatus including means for signaling a malfunctioning of same.

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