US3267894A - Article stringing machines - Google Patents

Description

Aug. 23, 1966 Filed May l5, 1963 H. A. IMHOF ARTICLE STRINGING MACHINES 4 Sheets-Sheet l Allg- 23 1966 H. A. IMHOF ARTICLE STRINGING MACHINES 4 Sheets-Sheet 2 Filed May 15, 196s Aug 23. 1966 H. A. IMHOF 3,267,894

ARTICLE STRINGING MACHINES Filed May 13, 1963 4 Sheets-Sheet 5 75 36 c?? Aug. 23, 1966 H. A. IMHOF ARTICLE STRINGING MACHINES 4 Sheets-Sheet 4 Filed May 13, 1963 United States Patent O 3,267,894 ARTICLE STRINGING MACHINES Herman A. Imhof, Hamilton, Mass., assignor to United Shoe Machinery Corporation, Boston, Mass., a corporation of New Jersey Filed May 13, 1963, Ser. No. 279,749 8 Claims. (Cl. 112-104) This invention relates to improvements in article stringing machines and more particularly to a solution of problems which arise in Such prior machines as a result of operating upon highly resistive materials.

In an article Stringing machine such as that disclosed in application Serial No. 117,219, filed June 15, 1961, in the names of Charles P. Cardani et al., now U. S. Patent No. 3,142,896, as further improved by the disclosures of my copending United States applications for United States Letters Patent Serial No. 184,804 filed April 3, 1962, and now U.S. Letters Patent No. 3,207,106 and Serial No. 202,552 tiled I une 14, 1962, and now U.S. Letters Patent No. 3,174,448, articles of merchandise or workpieces such as pairs of shoes are clamped one on each side of a pedestal .and thereafter strung together with or without the coincident attachment of a tag lbearing size and price indicia. In the Stringing operation the leading end of the strand is carried through the articles by a curved eyepointed needle which iS then retracted slightly to form a bulge in the Strand. The `'bulge is gripped 'by a pincer which thereafter manipulates the leading end while another pincer carries the trailing end to form a closed and sealed loop passing through the article or articles. The reliable formation of the bulge in the leading end to be gripped by the .pincer is necessary to the dependable operation of the machine since failure of the strand to bulge results in the strand being missed by the pincer. When the article being Strung iS composed of highly resistive materials a number of factors combine either to prevent the Aformation of the bulge or to eliminate it before it can be effectively gripped and brought Iunder the control of the pincer.

It is accordingly an object of the invention to provide improved means for controlling more reliably the formation of a Ibulge in the leading end of the Strand in article Stringing machines, and for retaining the bulge until it is gripped by a pincer of the machine.

Another object is to provide novel means for supporting a workpiece against displacement under the force of needle penetration when the workpiece is composed of more resistive materials than have heretofore been operated on by Stringing machines.

Another object of the invention is to improve the clamping of articles in Stringing position.

Still a further object is to minimize deformation of the needle and avoid its breakage runder the forces of penetrating resistive materials.

A more limited but important object is to reinforce the needle without imposing frictional drag upon it.

In the achievement of the foregoing objects a feature of the invention relates to a lock installed for preventing movement of a clamp Similar to that employed in the machines of the above-identified application. When the prior machines are being employed for Stringing together pairs of articles such as shoes one shoe iS clamped against each Side of the pedestal and the needle thereafter penetrates both shoes to carry the leading end of the Strand through both shoe uppers. In penetrating the lirst shoe little diiliculty is experienced with the related clamp since the thrust of the needle presses the Shoe toward the pedeStal. The thrust of the needle in penetrating the second Shoe, however, is resisted by a clamp aS the needle pushes the Second shoe away from the pedestal. The left clamp which holds the Second article against the ICC pedestal does So under a spring force and when the force required for the needle to penetrate the article exceeds the force of the spring, the article follows the clamp until the thrust is relieved either at the time that needle penetration is completed or later in the operating cycle of the machine when the needle is partially retracted lfor the purpose of forming a lbulge to be gripped by a pincer. In either event the effect of clamp deflection and return, in accordance with the force being exerted by the needle upon the workpiece, is to prevent the formation of the necessary bulge in the leading end of the strand, and consequently preventing the reliable gripping of the leading end of the strand by a pincer for subsequent manpulation. As a result of the lock, .according to the present invention, the needle thrust absorbing clamp is retained in article gripping position Without Substantially increasing the spring force which would add materially to operator fatigue.

According to another feature of the invention, an auxiliary needle guide prevents excessive needle deflection while penetrating resistive materials. The auxiliary guide is coupled to a needle drive Sector on the machine in such a way that there is no relative motion between the guide and the needle while the needle is being subjected to deforming forces. The auxiliary needle guide driving means comprising a pin and ball arrangement positions the guide at the time that the first article is being penetrated, so that the unsupported length of needle is approximately half of the length.

Numerous advantages and features of the invention will be better understood from the following description of an illustrative embodiment taken in connecton with the accompanying drawings in which,

FIG. 1 is a fragmentary view in la left side elevation of an article Stringing machine, including a clamp and lock according to the present invention;

FIG. 2 is a fragmentary view in front elevation of a pedestal and article clamps in which one of the clamps is provided with the lock of FIG. 1, and in which the needle is provided with an auxiliary guide;

FIG. 3 is a View of devices related to the needle including the auxiliary guide of FIG. 2 with the parts shown in exploded relationship;

FIG. 4 is a fragmentary plan View showing a bridge for reenforcing the pedestal;

FIG. 5 is a detail view in front elevation and partly in Section Showing clamp operating connections and the clamp lock of FIGS. 1 and 2;

FIG. 6 is a detail perspective view Showing the construction of the work clamps;

FIGS. 7 and 8 are fragmentary views in front elevation showing relative positions of the needle and auxiliary guide at the Start of needle penetration through a iirst article and after complete penetration of two articles by the needle respectively; and

FIG. 9 is a Schematic view on an enlarged scale Showing the formation of a bulge in the leading end of the Strand and the gripping of the bulged portion of Strand by a pincer.

Referring to FIGS. 1 and 2, the present machine includes a subframe 10 and a pedestal 12 corresponding respectively to the subframe and the pedestal 256 of the above-identified Cardani et al. application. As in my application Serial No. 202,552 there is also included in the machine a curved eye-pointed needle 14 mounted in a needle carrier 16 and provided with a needle guide 18 which will be referred to in -the present Specification aS the main needle guide. The needle carrier 16 and the main guide 18 are both journaled on a short shaft 20 ixedly supported in the subframe 10 and the needle carrier is driven to actuate the needle through a Work penetrating Stroke through connections including an integral pinion 2-2 meshing with a cam actuated sector 24.

A typical operation of the machine consists of penetrating a pair of articles fragmentarily illustrated in the drawings as a pair lof shoes 26, 28 held against the left and right side of the pedestal respectively, by clamp pads 30 and 32. In penetrating -the articles the needle carries the leading end of a strand 34 to the position depicted in FIG. 8 and by being withdrawn slightly causes the formation of a bulge in the leading end of the strand as shown in PIG. 9 to rbe gripped by a iirst or left pincer indicated generally at 36. The needle 14 is then completely withdrawn and. a second or right pincer indicated generally at 38 grips the strand 34 between the iirst penetrated article and the eye of the needle before the strand is severed by a severing device, indi-cated generally at 40 in FIG. 4. Thereafter ythe ends -of the severed strand, the length of which may be controlled, as disclosed in my application Serial No. 184,804, or as set -forth in the Cardani et al. application, are manipulated to form a closed loop by forming bights from the end portions about an eyeleting lspindle 42 mounted on the pedestal 12. Thereafter the two hights are secured together by means of an eyelet which may also couple a tag to the strand, the eyelet clinching being -accomplished by an eyeleting tool 44 cooperating with the spindle 42, as is already well understood.

Workpieces operated upon 'by the present machine frequently include laminated Acounter materials which are much more resistive to needle penetration than ordinary shoe uppers heretofore considered difficult to penetrate. As shown in FIG. 9 such a workpiece may be in the form of an imitation Shearling slipper including an upper 46 of leather, a thick laminated counter 48 and a heavy pile imitation Shearling lining 50. This type of workpiece is highly resistive to penetration by the needle 14 and in prior machines has resulted in unreliable 'bulge formation in the leading end of the strand. A part of this diflculty is traceable to deflection of the pedestal in the direction of needle penetration. In the present machine this deflection has been cured by .providing a bridge between the subframe and the pedestal 12 in the form of a strap 52 secured by screws 54 to the subframe 10 and having its other end formed with a shallow slot the walls of which embrace the thickness of the rearward end of the pedestal. The screws 54 pass through the strap and an abutment member for operating the severing device 40 and are threaded into an integral ear of the subframe.

Another diliiculty in prior machines when operating upon highly resistive materials is that the clamp pad corresponding .to that 4designated by the reference numeral 30 is pushed away from the pedestal by the thrust of the needle. The movement of the left clamp in prior machines is partly the result of deformation of the clamp pad supporting structure. As seen in FIGS. 2, 5 and 6 particularly, the supporting structure lfor both the clamp pads 30 and 32 have been substantially reenforced. In the present machine the pad 30 is pivoted near the lower end of a slotted arm 58 formed integral with the forward end of `a body 60 of irregular cross section to adapt to the highly crowded environment of this area of the machine. The =body 60 is in -turn integral with a projection 62 bored to fit lthe shaft 20. The projection 62 extends as a sleeve -64 having a considerable length on the shaft and the parts 62 and `64 are retained against endwise motion between a shoulder on `the shaft and a snap Aring 66 iitted to the rearward end of the shaft. The parts 58, 60, 62 and 64 may be in the form of a steel weldment if great care is exercised to prevent exure at the joints -or alternatively may be machined from a single piece of metal. Similarly, the clamp pad 32 is pivoted at the lower end of a slotted arm 68 depending from a body 70 formed with a projection 72 having a rearwardly extending sleeve portion 74 bored to -be received 0n the sleeve 64 and also retained by the snap ring 66.

For urging the cla- mp pads 30 and 32 into pressing engagement with the work pieces there are provided, as in prior machines, a pair of tension springs stretched lbe- -tween each clamp body and a lixed anchor point. Thus there is associated with the body 60 a spring 76 connected to a pin 78 extending rearwa-rdly from the body 60. Similarly, there is a spring 80 connected to a pin 82 extending from the body 70 for urging the clamp pad 32 into engagement with its related workpiece.

For causing opening of the clamp pads to receive and release workpieces there is provided a T-shaped slide mounted actuator 84 connected as in prior machines with la treadle. The upper bar portion of the actuator 84 when raised engages a pair of rolls S6, 88 mounted respectively, on the pins 78 and 82 for causing the opening of the clamps against the spring bias. When the clamp operating treadle is released, a tension spring 90 causes the actua-tor 84 to move away from the rollers 86, 88 so that clamping pressure is applied to the pads 30, 32 by the springs 76, 80.

In prior machines the article in the position of the shoe 26, while being penetrated by the needle, is pushed by the force of needle penetration against the clamp pad and away from the pedestal, the restraining force being provided solely by the clamp spring which is necessarily limited in order to minimize fatigue to the operator in operating the clamp treadle. There is provided for the clamp pad 30 in the present machine a lock in the form of a wedge 94, seen in FIGS. 1 to 6. The wedge 94 is formed integral with a slide 96 of T-shaped cross section and vertically movable in a guideway formed for the purpose in a block 98 iixedly supported on the rearward surface of the pedestal and also providing a guideway for the Iactuator 84. The wedge 94 is urged downwardly by a tension spring 100 stretched between the lower end of the slide 96 and a fixed anchor block 102.

A simple but effective connection is provided for imparting a releasing motion to the wedge before the clamps are opened and a locking motion after the clamps are closed. As in the prior machine of my application Serial No. 202,552 the depressing of the spindle 42 is accomplished by the same treadle which causes the opening of the clamps and there is provided a delay so that the spindle is lowered before the clamps begin to open. For this purpose the lower end of the actuator s bifurcated to receive the thickness of a link 104 which is raised by treadle action to cause the opening of the clamps. The link 104 carries a pin 106 passing through slots 108 in the lower end of the actuator 84 so as to provide the necessary lost motion between the lowering of the spindle 42 and the opening of the clamps. It is thus seen that as the link 104 rises there is no motion imparted to the actuator 84 until the pin 106 reaches the upper end of the slot 108. The pin 106 extends to the left of the actuator as seen in FIG. 5 and its outward end underlies a projecting portion of the slide 96 so that as the link 104 is raised, but before there is any motion imparted to the actuator 84 the Wedge 94 is raised out of contact with the roll 86.

It is seen from the foregoing that the bridge 52 prevents deflection of the pedestal 12 and that displacement of the clamp pad 30 as a result of distortion of the clamp body from the force of needle penetration has been largely eliminated when operating upon materials within the resistivity limits of the machine by substantially stiiening the clamp pad supporting structure. In addition the wedge 94 which has a face engaging the roll 86 and dening with a vertical plane an angle of approximately 10 provides a substantial mechanical advantage to the force of the spring 100 in preventing Aswinging motion of the left clamp assembly including the pad 30 under the force of needle penetration. The wedge 94 is advantageous in that it provides effective locking action without materially increasing the force required by the operator upon the clamp operating treadle.

As already explained another factor which contributes to the diiculties experienced in forming a bulge from the leading end of the strand in prior machines is deflection of the needle under the force of penetration, the needle tending to assume a smaller radius of curvature so that its midportion is deected outwardly from its normal unstressed position. Under severe conditions this deection results in frequent needle breakage. In the present machine, the midportion of the needle is retained against outward deflection by an auxiliary guide 110 having an opening through which the needle passes freely and mounted for motion concentrically with the needle. It is extremely important to avoid additional cam actuated elements in the vicinity of the needle because of the already crowded conditions and the further complications that such connections would cause. At the same time it is necessary to achieve relative motion between the auxiliary guide 110 and the needle 14, and the relative motion must further be achieved at a time when the needle is subject to little or no deformation caused by the force of penetrating a workpiece. For this purpose there is provided a pair of detent driving connections between the needle carrier 16 and the auxiliary guide 110, each connection consisting of a pin and a spring pressed ball. As seen in FIGS. 2 and 3 which depict the rest condition of the machine, the rst auxiliary guide driving connection which imparts motion to the guide as the needle 14 moves toward the workpiece 2S, includes a pin 112 pressed into and projecting forwardly from a radially extending portion of the needle carrier 16. The pin 112 passes through an arcuate slot 114 in the guide 110 and provides the driving connection by engaging a ball 116 pressed radially out- Wardly by a spring 118. The pin 112 performs the additional function of anchoring one end of a torsion spring 120 which urges the main guide 18 to advance toward the workpiece 28 in step with the needle 14. The main guide 18 travels with the needle until the guide reaches the position of FIG. 8 in which it engages a stop 122 on the pedestal 12 and thereafter the needle continues to move through the guide 1S. It will be noted that the main guide 18, as seen in FIG. 7, is reaching its most advanced position toward the work at just about the time that the point of the needle commences to penetrate a workpiece of average thickness held by the clamp 32. At this time in the machine cycle when the needle undergoes the stress of penetrating the rst article the auxiliary guide 110 driven from the needle carrier 16 through the connection 112, 116 is moving toward the clamp pad 32 in step with the needle 14, there being no relative motion between the auxiliary guide and the needle. This absence of relative motion between the needle and the auxiliary guide while the needle is under stress, is important to avoid serious scoring, rapid wear and possible binding together of the needle and auxiliary guide. The needle and auxiliary guide continue to travel together until the auxiliary guide comes to rest against the back of the already-stopped main guide 18. A notch 123 formed in the guide 110 centralizes the strand 34 with the needle and prevents the pinching of the strand between the two guides. At this point the pin 112 escapes from the ball 116 and the needle continues in motion while the auxiliary guide remains stationary. As may be judged from the relative positions of the guide 18 and the auxiliary guide 110 on the one hand and the thickness of the pedestal 12, which determines the spacing between workpieces, the escape of the pin 112 from the ball 116 occurs after the first .article illustrated as the shoe 2S has been completely penetrated by the point of the needle but before the needle engages the second article 26.

A second connection comprising a pin `124 pressed into the carrier 16 and extending forwardly in spaced parallel relation with the pin 11-2 and a b-all 126 pressed radially outwardly by a spring |128, is provided for returning the needle guide 1 10 to its proper starting position for the next operating cycle of the machi-ne.

As the auxiliary guide 110 reaches the position in which it is shown in FIG. 8, the pin 112 depresses the ball 116 and escapes. Shortly thereafter as the needle carrier 16 continues in motion the pin 1,24 depresses the ball 126 and moves ahead of the ball in the clockwise direction. iBut it will be noted that as `the shoe 28 is penetrated the auxiliary guide y1=10` is `at approximately the midpoint of the otherwise unsupported extent of needle length and -is moving with the needle so that there is no :relative motion between the needle and the auxiliary guide. While the needle point is penetrating the shoe 26 rthe half of the needle nearest the carrier 14 is sliding in a xed support consisting of the combination of the main guide 18 and the auxiliary guide 110 and accordingly the danger of abrasive dama-ge to the needle surface in contacting with the guides is substantially reduced because the load is distributed over a relatively large area.

As the needle having been rotated to form a bulge to be .gripped by the pincer 36 is retracted toward the position of IFIG. 2 the pin '124 engages the ball 126 and |the auxiliary guide '110 is thereby carried in a counterclockwise direction with the `carrier 16. In order to reset the connection 112, *116 for the next article penetrating stroke of the needle there is provided a downwardly extending nger l130 dixedly mounted on the .frame in Iwhich the eyeleting tool 44 is slidably supported. In proceeding in a counterclockwise direction during retraction `of the needle 114, the auxiliary guide ,110 is carried until it abuts the finger 13G. Thereafter the pin -124 which continues in motion escapes from the ball f126 and the pin 112 also passes the ball |116 to be prepared for driving the auxiliary guide in the clockwise direction during the next operation of the machine.

Very crowded -conditions .are encountered in the mounting of the main and auxiliary guides yin effective positions. As may be seen in FIG. 3, the needle carrier is formed with a short cutaway forwardly extending hub 132 and provided with a pressed oilless bronze bearing 134 the Iinside diameter of which tits the shaft 20. The main guide 18 is bored to be received upon the bearing 134 and has a longer rearwardly extending hub 136 cut away to cooperate with the cutaway hub 132 as will be explained. The inside diameters of the two hubs 134, 136 are matched and are received within the auxiliary guide 1110, so that the `guide I'1110 is free to pivot on the hubs. The cutaway section of the hub l134 provides a radially extending surface 138 'which engages a surface 140 on the hub y'136 to return the main guide 18 to the position depicted in FIG. 2 as the needle carrier 16 is returned to its inactive position.

Having thus described my invention what I claim as new and desire to secure by letters Patent of the United States is:

1. An article Stringing machine comprising a pedestal, means for holding a workpiece against the pedestal, a curved eye-pointed needle, a carrier upon which the needle is mounted to be oscillated to carry the leading end of a strand through the workpiece and to retract, a main needle guide located near the point of the needle as the workpiece is being penetrated, an auxiliary needle guide for supporting the midportion of the needle, and a driving connection `for the auxiliary guide from the needle carrier to impart motion to the guide in step with the needle at the time of workpiece penetration.

2. An article stringing machine comprising a pedestal, means for holding a workpiece against the pedestal, a curved eye-pointed needle, a carrier upon which the needle is mounted to be oscillated to carry the leading end of a strand through the workpiece and to retract, a main needle guide located near the point of the needle as the workpiece is ybeing penetrated, an auxiliary needle guide for supporting the midportion of the needle, and a driving connection ybetween the needle carrier and the auxiliary needle guide including a spring .pressed bal-l -in one member anda pin in the other member.

3. An article `Stringing machine comprising a pedestal, means for holding a workpiece against the pedestal, a curved eye-pointed needle, a carrier upon which the needle is mounted to be oscillated to carry the leading end of a strand through the workpiece and lto retract, a main needle guide located near the point of the needle as the workpiece is lbeing penetrated, .an `auxiliary needle xguide for supporting lthe midportion of the needle and a pair of connections for the auxiliary needle guide each including a spring pressed :ball in the needle guide and a pin in the carrier, the first driving connection being effective during needle motion in a tirst direction and the other connection being operative 'for return-ing the auxiliary guide to its starting position.

4. An article Stringing machine comprising a pedestal, means Ifor holding a workpiece against the pedestal, a curved eye-pointed needle, a carrier lupon Which the needle is mounted to be oscillated to carry the leading end of a strand through the workpiece vand .to retract, a main needle guide ylocated near the point of the needle as the workpiece is @being penetrated, an auxiliary needle guide for supporting the midportion of the needle, a irst conneet-ion between `the auxiliary guide and the carrier including a spring pressed ball on the auxiliary yguide and a pin mounted on Lthe carrier and positioned to engage the Aball to impart motion to the auxiliary guide in step with the needle while the needle is penetrating the workpiece and a second connection including 1a second spring pressed hall on the auxiliary guide and a second pin on the car- Tier for returning the auxiliary guide to its starting position.

5. An article stringing machine comprising a pedestal, a curved eye-pointed needle, means vfor oscillating the needle to carry the leading end of ya strand through a workpiece clamped against .the pedestal and to retract, a clamp kfor holding the workpiece against the pedestal and clamp locking means including a slide mounted wedge -for preventing displacement of the clamp from its workpiece holding position under the thrust of the needle.

6. An article Stringing machine comprising a pedestal, a curved eye-pointed needle, means for oscillating the needle to carry the leading end of a strand through workpieces clamped against the pedestal and to retract, a pair of 'work clamps the second one of which retains one of the Workpieces in contact with vthe pedestal against the thrust of the needle, an actuator for opening the clamps, a locking Wedge for the -second clamp yand a lost motion connection between the actuator and the wedge for unlocking the Wedge before an opening motion is imparted to lthe clamps.

7. An larticle .Stringing machine comprising a pedestal, a curved eye-pointed needle, means for oscillating the needle to carry the leading end of a strand through Workpieces clamped against the pedestal and `to retract, a pair of Work clamps the second one of Which retains its related workpiece in contact with the pedestal against the :thrust of the needle, a locking wedge, :a spring urging the wedge into locking engagement with .the second clamp, clamp opening connections and means interposed between the connecti-ons and the wedge for releasing the wedge from locking engagement before the clamps are opened.

8. An .article Stringing machine comprising a pedestal against which a workpiece is 'held in `Stringing position, la curved eye-pointed needle, a carrier upon which the needle lis mounted to be oscillated to carry Athe leading end of the strand through the workpiece and to retract, a clamp holding the workpiece in contact with the pedestal against the force of needle penetration, clamp locking means to prevent displacement of the clamp under the force of needle penetra-tion, a pincer for gripping 'a bulge formed in the leading end of the strand as the needle is retracted, a needle guide supporting a portion of the needle near the point, and an auxiliary guide coupled to the carrier for supporting an intermediate portion of Ithe needle whereby lthe bulge in the leading end of the strand is formed reliably to be gripped by the pincer.

References Cited by the Examiner UNITED STATES PATENTS 3,166,035 1/1965 Wiegand 112-104 X JORDAN FRANKLIN, Primary Examiner.

G. V. LARKIN, Assistant Examiner.

Claims (1)

1. AN ARTICLE STRINGING MACHINE COMPRISING A PEDESTAL, MEANS FOR HOLDING A WORKPIECE AGAINST THE PEDESTAL, A CURVED EYP-POINTED NEEDLE, A CARRIER UPON WHICH THE NEEDLE IS MOUNTED TO BE OSCILLATED TO CARRY THE LEADING END OF A STRAND THROUGH THE WORKPIECE AND TO RETRACT, A MAIN NEEDLE GUIDE LOCATED NEAR THE POINT OF THE NEEDLE AS THE WORKPIECE IS BEING PENETRATED, AN AUXILIARY NEEDLE GUIDE FOR SUPPORTING THE MIDPORTION OF THE NEEDLE, AND A DRIVING CONNECTION FOR THE AUXILIARY GUIDE FROM THE NEEDLE CARRIER TO IMPART MOTION TO THE GUIDE IN STEP WITH THE NEEDLE AT THE TIME OF WORKPIECE PENETRATION.

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