US3059386A - Strapping machine - Google Patents

Description

Oct. 23, 1962 E. J. voRRATH ETAL 3,059,386

sT PPIN HINE gy www Oct. 23, 1962 E. .1. voRRATH ETAL STRAPPING MACHINE 6 Sheets-Sheet 2 Filed Dec. 2, 1959 INVENToRs. merli/UWM BY alum/L win/Mex Oct. 23, 1962 E. J. voRRATH ETAL STRAPPING MACHINE 6 Sheets-Sheet 5 Filed DeC. 2, 1959 E. J. VORRATH El' AL Oct. 23, 1962 STRAPPING MACHINE 1r, 4 s( w@ m uw mw www m V w mJIn O.. e l m L Y B ww 1| QQ m m @N m Oct. 23, 1962 E. J. voRRA-rl-l ETAL 3,059,386

STRAPPING MACHINE Filed Dec. 2, 1959 6 Sheets-Sheet 5 lll- Imlllllll mm l 1N VEN TORS Ebner IZ/armi?? octzs, 1962 E. J.VORRATH ET AL 3,059,386

STRAPPING MACHINE Filed Dec. 2, 1959 6 Sheets-Sheet 6 United States Patent O 3,959,386 ST PING MAC Elmer ll. Vorrath, East Hazelcrest, and Alvin L. Winkler,

Chicago, ill., assignors to Acme Steel Company, Chi'- cago, lll., a corporation of illinois Filed Dec. 2, 1959, Ser. No. 856,S53 2S Claims. (Cl. 53-13) closed strap loops radially around the annular portions of the coil. In order .to position the straps, a widely used method is to feed the strap endwise and manipulate the strap end into a loop about the annular portions of the coil. In doing this, auxiliary strap guide means can be used to yfacilitate lthe manipulation. Where the coils are delivered on a conveyor system the auxiliary strap guide means is usually limited to guiding the strap at a level below the delivery height of the coil because the guide cannot project above the level of the conveyor where it would interfere with movement of the coil. `For this reason the guide usually does not help much toward directing the strap end to a position -where it can be conveniently grasped by the worker and, so, it is ordinarily necessary for the worker to reach down into the center of the coil to grasp the strap end prior to encircling the strap on the coil, or else, if the guide directs the strap lthrough the center of the coil, it `ordinarily directs it away from and beyond the normal reach of the worker. In order to overcome this diiiiculty, it is the principal object of the invention to provide an improved guide means which assists the worker by causing the strap end, upon endwise feeding of the strap, to bulge upwardly through the central opening of the coil where a worker can conveniently grasp it. lt is another object of the invention to provide such an improved guide means which causes the strap end to bulge upwardly through the central opening of the coil, which bulge can be regulated in size by mere regulation of the amount of Strap feed, thus enabling the worker to grasp the strap at Whatever level is convenient for him.

lt is another object of the invention to provide a strap guide of the type mentioned which is aplicable for use on a strapping device wherein the strap feed is performed completely by hand or is readily adapted for use with means Which automatically or semi-automatically feeds the strap and secures the overlapping ends of the strap loop together after the loop is encircled about the coil portions.

lt is another object of the invention to provide an improvide strapping device having a strapping head yfor tensioning and joining together the ends of a strap loop encircled about an object which strapping head is mounted in such a way that it can be locked in position relative to its support but still be provided with a floating action which insures acquiring equalized tension of the strap loop on the coil during the strap tensioning period.

It is still another object of the invention to provide an improved strapping device embodying both the improved strap guide of this invention which is used for assisting in the formation of the strap loop around the coil portions and a strapping head of a type which is used to feed the strap, tension the strap, and secure the overlapping strap ends of a loop encircled about a coil portion, wherein the strapping head is movably mounted in such a way 3,059,385 Patented Oct. 23, 1962 ice that it can be locked in position relative to its support but still be provided with a iloating action which insures acquiring equalized tension of the strap loops on the coil when the strapping head causes the strap to be tensioned.

It is another object of the invention to provide an im proved method of making a binder strap available for conveniently encircling it around an object.

Another object is to provide an improved method of making a binder strap available for conveniently encircling it around an annular object.

Other objects and advantages of the invention should become apparent by referring to accompanying drawings in which lFIG. l shows -a perspective view of the upper portions of a strapping apparatus embodying the invention and includes a showing of the relative position of a worker using the apparatus to strap coils of strip material;

FIG. la shows a perspective view of a coil of strip material after it has been strapped with the apparatus of FIG. l;

FIG. 2 shows a top plan view of the strapping apparatus embodying rthe invention;

iFlG. 3 shows an upper elevation of the apparatus of FIG. 2;

FIG. 4 shows a sectional FIG. 2;

FIG. 5 shows an enlarged view of a portion of the strapping head as viewed in the central region of FIG. 2;

FIG. 6 shows a sectional view of strapping head portions along the line 6-6 o-f FIG. 5, and

FIG. 7 shows a partial sectional view along the line 7-7 of FIG. Q, and particularly shows the relationship of the strapping head with the improved strap guide of this invention.

The apparatus of this invention is used to facilitate strapping of coils of stri-p material of the type shown in FIG. 1a where a coil 1, having been wound into an annular or ring shape, is provided by the apparatus With closed loops 2 of binder strap which are secured tightly in radial directions around annular portions of the coil in a radial direction. These loops 2 of strap are secured by joining together the two overlapping ends of the strap forming each loop by deforming the two overlapping strap ends and a tubular metal seal 3 encircling them to form a joint 4.

As sho-wn in FIG. l, a plurality of coils is supported on three conveyor units S, 6 and 7. The conveyor unit 5 is any conventional roller type conveyor provided with free wheeling rollers 8 journaled to a supporting frame 9, the coils 1 being adapted to roll freely across the upper surfaces of the rollers S, from a region where the coils are Aformed from continuous strip lengths. The conveyor unit 6 is actually part of the strapping apparatus embodying this invention and it has free wheeling rollers 10 of the same type as the rollers 8 of the unit 5 so that the coils 1 can be transported freely across their upper surfaces. After the coils 1 have been strapped they are passed beyond the rollers 10 to the conveyor unit 7 which is divided into two parts 7a and 7b, each being provided with -free wheeling rollers 11a and 11b, respectively, on which the coils 1 can be easily transported.

Although the conveyor units S and 7 may be of any conventional type, the conveyor unit 6` is a necessary part of the apparatus associated with the strapping means of this invention. This unit 6 is associated with a strapping head 12 which is provided `with means for feeding a length of strap endwise from a source of strap supply and is thereafter adapted to tension the strap by reverse endwise feeding of the strap after the strap is encircled in a loop about a coil portion, and then it secures together the overlapping strap ends of the loop encircling the coil portion and severs the supply of strap end from view along the line 4-4 of the secured strap loop. One of the principal features of the invention is the apparatus providing for positioning the leading end of the strap where it is convenient for the operator to grasp it during thestrapping operation. The manner of operation when strapping the coils 1 is for the operator to cause the strapping apparatus 12 to feed a lengthl of strap endwise below the level of a coil 1 supported on the unit 6. The strap is fed as far as the region adjacent the central opening y1a of the coil -1. Ordinarily it is necessary tor the operator or worker 13 to reach into the opening =1a and grasp the leading end 14a of the strap l1&1. Hethen manipulates the leading strap end 14a into a loop about an annular portion of the coil -1 in a direction radially of the coil and then inserts the leading strap end 14a beneath the coil in overlapping relationship with the supply strap end 14b. It is desirable to guide the leading strap end 14a up through the opening-1a of the coil 1 to a height above its upper level where it can more easily be grasped by the worker 13- but, when the ordinary guide is used which directs the strap through the center of the coil, it ordinarily is directed away and beyond the normal `reach ofthe worker so that he must extend his reach to grasp the leading end 14a. Also, because the coils 1 must be freely passed over the rollers 10 of the conveyor unit 6, it is undesirable to have any guide projecting above the level of the rollers lil'. Therefore, 'it is diliicult to provide adequate guide means vto accomplish the resultwithout any upwardly projecting strap guide members. The manner of doing so is by providing a strap guide below the level of the rollers which is provided with an Yabutment specially shaped to cause the leading strap endA tobe halted at its` extreme end and thereupon caused to be bulged upwardly behindits extreme end into-an upwardly extending bulge portion y141e or bubble of strap, as it is referred to, to alevel where it can be conveniently grasped by the Worker. The advantage of the bulge portion 14C is that there is no freely extending unsupported Vendrextending randomly into the air which, due to its own springiness and ilexibility, would tend to vibrate lback and forth as it is fed to thereby make it more diicult lfor the operator to grasp. The bulge portion provides a length of strap formed into a loop whereby the leading end is held temporarily secured and the supply end is also restricted in movement with the result that the bulge portion 14p is relatively controlled in its movement and assumes a much more regulated path of movement than the Vsituation where the free end of the strap is fedV ordischarged into the air in an unsupportedrmanner. The effect of this is that the operator knows exactly where to reach for the bulge portion 14e of the strap and, consequently, is provided with greater facility for the strapping operation which is believed to make him more eicient by cutting down fatigue and thereby accelerating the strapping operation. As particularly shown in FIGS. 1, 2,. 3 and 4, the unit 6 consists of the rollers 10 which are of diiferent lengths depending upon their location on the unit 6. in ladd-ition to the rollers 110, there are three taperedrollers 1S, 16 and 17. These rollers are journaled at their near ends in vertically extending bearings 15a, 16a and 17a, respectively, and at their outer ends in bearings 15b, 16h and 17h, respectively, which are secured in substantially vertically extending plates 15e, -16c and 17C, re-V spectively. The reason that the rollers '10 are of different lengths is to provide -for the positioning of the tapered rollers 1'5, 16 and 17 in spaces between them (FIG. 2). The bearings 15a, E16a and 17a are secured to brackets 15d, 16d and 17d which are secured by means of screws 18 to a spider 19 having three radially extending arms 20, one for each of the tapered rollers 15, 216 and 17. Each of the brackets 15e, -16c and 17eV areV secured by meansV of screws 21 to the end of its respective arm of the spider 19. The spider 19 isprovided i at its central region with a hub 22 which tits over the upper end 23 of a shaft 24 and is held secured to this upper end 23 by means of a screw 25 passed through the outer end of the hub 22 and threadably engaging the shaft 24 in a longitudinally extending threaded hole. The shaft 24 passes through a circular hole 26 extending vertically through a sleeve 27 which is secured to an intermediate frame member 6a of the conveyor unit 6. The lower end of the shaft 24 is provided with an upwardly extending hole `28 which is provided with the upper end 29 of the piston rod 30'. The iit between the upper end 29 of the piston rod is very loose so that space is provided between the outer wall of the piston rod and the inner wall of the hole 28. The lower end of the piston rod 30 is secured to a piston 31 contained in a cylinder 32. Upon proper introduction of iiuid or .air into the cyiinder 32, the piston 31 is caused to move in such a way that the piston rod 30 is either extended or retracted. When the piston rod is extended, the spider 19 is ele- `vated to cause the tapered rollers 15, 16 and 17 to likewise be elevated above the level of the top surfaces of the rollers 16. When this is done, a coil 1 resting on the rollers 11d above the positions of the tapered rollers 1,15, 16 and 17 is raised by these tapered rollers above the level of the rollers l@ so that the coil 1 rests only on the tapered rollers 15, 16 and 17. When the piston rod 3d is retracted, the tapered rollers 15, 16 and 1'/ are lowered below the level of the upper surfaces of the rollers 1) so that the coil 1 again rests upon the rollers 10 free and clear of the tapered rollers.

Y The outer ends of both of the rollers 15 and 16 are provided with integral hanged sheaves 33- which are encircled with portions of a continuous lflexible belt 34. Secured to the under surfaces of the two arms Zit corresponding to the locations of the tapered rollers 15 and 16 are two depending inverted U-shaped brackets 3S and 36 which each rotatably support two additional sheaves 37 and 38. These sheaves are aligned parallel with each otherV and angularly with the sheaves 33 in a manner as particularly shown in FIG. 2 so that the continuous belt 34 passes below them and extends in straight paths between them. ln this manner la continuous belt 34 passes up and over a tirst sheave 33t, -down around a sheave 38, over to and below a sheave 37, up and around the other sheave 33, down to the other sheave 37 and around beneath it, and finally in a straight path over to the first mentioned sheave 33 to complete the closed circuit path. The shaft of the tapered roller 16 extends outwardly beyond the sheave 33 attached to it and the shaft is provided With a hand crank 39 which maybe used to rotate the tapered roller 116 on its axis. While so doing, the continuous belt 34 is also actuated as the corresponding sheave 33 is rotated with the tapered roller 116. Movement of the continuous belt 34 is transmitted to the other sheave 33 attached to the tapered roller 15 with the result that the roller 15 is similarly rotated when the roller 16 is. The purpose of rotation ofV these two rollers 15 and 16 is to cause the coil y1 positioned on the rollers to be rotated after a strap is secured to it so that a strap may be secured in a new location on the coil without relocating the strapping unit 12.

The conveyor unit 6, in addition to being provided with the rollers 10, 1S, 16 and 17, `and their related supporting structure, is also provided withY a special strap end guide 4t) at its central region approximately at the point of convergence of the three axes of the tapered rollers 15, 16 and 17. This is the region above which the central opening 1a of a coil 1 is automatically positioned for strapping purposes. The strap end guide 49 consists of two side plates 41 and 42 which are used to radially guide the leading strap end 14a when it is fed into the strap end guide. These side plates 41 and 42 are securely mounted in a permanent position to the frame of the conveyor unit 6. Between the two side plates 41 and 4Z is secured to a strap end stop 43 which is a specially shaped flat strip for accomplishing one of the main objects of the invention. This strap end stop 43 is eX- plained in more detail hereinafter.

The strapping apparatus 12 embodied as part of the invention is supported by four grooved wheels 44 which ride on two inverted V-shaped tracks 45 and 46 which rest on a plate 47 secured to the floor. rlhese wheels 44 are journaled freely on shafts 48 which are secured to two parallel frame members 49 and 5G` which have secured to them vertical frame members 51 and 52, These vertical frame members 51 and 52 are held parallel to each other by means of a transverse frame member 53 and also by a plate 54 also secured between the frame members 49 and 50. All of the frame members 49, 50, 51, 52, 53 and 54 provide an integral carriage for the support of a strapping head 55. rl`he strapping head 55 is provided at its upper end with apertured ears 56 which are trunnioned through their apertures on a shaft 57. The shaft 57 has its two ends journaled in pillow blocks or bearings 58 and 59 mounted by means of screws 60 to the upper ends of the frame members 51 and 52. In this manner the strapping head 55 is pivotally mounted on the shaft 57 so that it can pivot between the position shown in bold outline at 57 and its position as shown in dotted lines 55a in FIG. 4. The means for causing the pivotal movement of the strapping head 55 is an air cylinder 61 secured on an L-shaped frame member 62 secured between the two vertical members 51 and 52. The cylinder 61 is provided with a piston rod 63 which is pivoted to a projection 64 at the rear end of the strapping head 55. When air or other fluid is properly admitted to the cylinder 61, the piston rod 63 is either caused to extend or retract. When it is extended, it causes the strapping head 55 tol pivot in a clockwise direction as viewed in FIG. 4 and, when it is retracted, it causes the strapping head to be pivoted in the opposite direction. Clockwise pivoting of the strapping head 55 raises the joint forming mechanism 55h of the strapping head 55 to be elevated up to the region of a coil 1 resting on the tapered rollers 15, 16 and 17 where it can be used to secure the overlapping ends of a strap loop encircled on the coil 1. Pivotal movement of the strapping head 55 in a counter-clockwise direction causes the joint forming mechanism 55h to be lowered away from the coil region and aligns strap guide portions of the strapping head 55 in its proper strap feeding relationship with the strap end guide 40 in preparation for the beginning of a strapping cycle.

The strapping head S5 can be of many different forms and, in some cases, can be entirely eliminated, provided hand tools would be used for the formation of a strap joint. The advantage of using a strapping head 55 of the nature to be generally described is to accelerate the strapping cycle for increased speed and eiiiciency.

In addition to the joint forming mechanism 55b, the strapping head 55 may have a coil of strip 65 from which tubular metal seals can be formed in the head itself rather than providing preformed seals or clips as is sometimes ordinarily done. In addition, the strapping head 5S must be provided with some sort of strap feed mechanism which feeds the strap longitudinally in both a forward and reverse direction. Many forms of strap feed are possible and available. However, it is suicient that the strap 14 be guided through the machine from a source of supply which may be in the form of a coil of strap material, in the ordinary situation, and have a toothed feed wheel 66 engaging the strap 14 -against the periphery of an idler wheel 67. In this manner, rotation of the feed wheel 66 causes movement of the strap 14 around the idler wheel 67. In order to maintain the proper path of the strap through the strapping head, appropriate guide means can be used.

As an example of the type of strapping head 55 which may be used, FIGS. 5 and 6 show some of the details of such a unit. The joint forming mechanism 55h consists of a plurality of jaws 68 which can be appropriately actuated to deform a metal seal 3 encircled about two overlapping strap ends 14a and 14h to form a conventional interlocking type joint 4 as indicated generally in FIG. la. Before the joint is formed, the leading end 14a of the strap is gripped by means of two jaws 69 which press the strap end 14a against a plate 70 and grip it tightly by action of sharp projections 69a protruding from the tips of the jaws 69. After the joint is formed between the seal and the strap ends, a shear plate 71 is moved longitudinally to shear the supply of strap 14 from the strap loop 2 encircling the coil. The seal forming mechanism is generally indicated at 72 and consists of an anvil 73 over which a seal 3 can be formed into a U-shape as a U-shape plunger 74 is actuated against the anvil 73. After the seal 3 is formed, shoulders 73a on the anvil 73 are used to feed a seal 3 forward and in between the sealing jaws 68 in preparation for reception of the strap ends of a newly formed strap loop 2.

In general operation of the apparatus, the worker 13 stands in a position as shown in FIG. l. In this situation, the coils 1 of strip are moved in the direction of the arrow 75 along the conveyor units 5, 6 and 7. An unstrapped coil 1 is moved manually from the conveyor unit 5 to strapping position centrally of the conveyor unit 6 to a position shown by dotted lines in FIG. 2 with the central opening 1a of the coil 1 positioned above the strap end guide 40. With the coil properly positioned, the strapping unit 12 is operated by power means within it to cause rotation of the feed wheel 66 in a clockwise direction as viewed in FIG. 4. This causes the strap 14 to be fed endwise in the direction of the arrow 76 (FIG. 4) and around the idler wheel 67, through the guide portion 77 (FIG. 2) of the strapping head S5, past the joint forming mechanism 55b and the anvil 73,` and nally into the strap end guide 40 between its side plates 41 and 42. As particularly shown in FIG. 7, the strapping head 55 is lowered by pivotal movement on its shaft 57 to its lowermost position indicated by dotted lines 55a upon proper actuation of the air cylinder 61 so that its piston rod 63 is retracted. This position of the strapping head 55 aligns the strap guide means 77 so that the strap 14 fed longitudinally through it is direct-ed at the proper level into the strap end guide 4d along an upwardly sloped surface 43a of the strap end stop 43. The extreme end 14C of the strap 14, in its longitudinal movement forward, strikes another downwardly sloped surface 43h of the strap end stop 43. The result of this is that the extreme end 14d is deflected in a path along the slope-d surface 431; untilit is arrested in its endwise movement by a downwardly sloped curved surface 43C. The downward deflection of the extreme end 14d creates an upward bow in the region 14e of the strap. As the strap 14 is continued to be fed forward, the action is such that the upward bow becomes larger in the form of a bulge portion 14e and extends into the opening 1a of the coil 1 and finally, if sufficient strap is fed, to a level well above the upper surface of the coil 1, as particularly shown in FIG. l, where the operator can reach out to a position as indicated by dotted lines 13a to grasp the bulge portion 14C preparatory to forming the lea-ding strap end 14a into a loop -around a portion of the coil 1. As the upward bulge 14C develops, the strap engages the upper corner 14]c of the guide and then lpivots at this corner to cause the strap end 14d' to slide around on the surface 43C in a reverse direction to the longitudinal travel of the strap 14 as indicated by the arrow 78. The location of the corner 14f is such that a locking action occurs on the strap end by its reaction between the corner 147 and the surface 14g of the guide so that the strap end is securely held in place.

After the operator or worker 13 grasps the bulge portion 14e` of the leading strap end 14a he directs it in a looped path radially around an annular portion of the coil 1 in a direction lirst toward him and then beneath the annular portion of the coil where a strap loop 2 is to be secured. This leading strap end is fed around far enough under the coil that it is delivered to the region of the strap gripping jaws 69. At that point, the strapping head 55 is caused to be actuated by power means which causes the gripping jaws 6? to grip the leading strap end 14a against the plate 70. It is also necessary that the leading strap end 14a be extended through a tubular seal 3 which, by proper operation of the strapping head, is already positioned within the joint forming mechanism SSb. Initially when the strap was fed forward, it too would have been fed through the tubular seal 3 so that the strap ends 14a and 14h assume positions indicated in FIG. 6i.V Next, further actuation of the strapping head causes retraction of the supply end Mb of the strap 14 to remove the slack from the strap loop 2 encircling the coil portion. When the slack has been removed, the joint forming mechanism 55h is actuated to produce an interlocking joint between the seal 3 and the overlapping strap ends 14a and 14h passing through it. Also, after the joint forming operation, the shear 71 is moved toward the plate 7! to shear o the supply end of strap from the strap loop 2 encircling the coil portion so that all parts are in positions as shown in FIG. 6. Y

At this time, the hand crank 39 is rotated to cause rotation of the tapered rollers 15 and 1d to orient the coil 1 to a. new position relative to the strapping head 55 so that another strap loop 2 can be positioned at another portion of the coil. After the cycle is repeated again, the coil is again rotated and a third strap loop 2 is secured on the coil. Ordinarily three strap loops 2 seem to be sufhcient, but more can be used if desired. Y

It should be made clear that it is not necessary to use a strapping mechanism as complicated as the strapping head 55 in order to obtain beneit from the use of the strap end guide 40. In fact, the strap end guide 4@ can be made use of even when the strap 14 would be fed forward manually into it. The same effect would-be achieved. The bulged portion 14C would occur and the operator would still have the advantage of being able to grasp the bulge portion 14C to increase his efficiency when strapping coils. In addition, the arrangement can be such that ordinary well known hand strapping tools could be used for tensioning the strap, for forming a strap joint and for severing the strap supply from the strap loop as it is secured on the coil. However, it is believed that there is greater speed when embodying the apparatus with an automatic or semi-automatic strapping Vhead 55 as generally described. Of course, it is also possible to use many diiferent type strapping heads and the details of the particular type strapping head shown herein does not constitute part of this invention per se.

When using a strapping head of the general type shown, it is desirable to relocate it when strapping different diameter coils so that the joint forming mechanism 55h of the strapping head is located in a proper position with respect to the coil so that a strap jointan be properly formed. Considering the size Yof the coil 1 shown in phantom lines in FIG. 2, it has an outer circumference 1b and an inner circumference 1c which denes the cir cular wall of the central opening la. It should be apparent that the joint forming mechanism 55h is positioned adequately to form a strap jointV on the coil when the circumferences are as shown at 1b and lc. However, ifV

a coil having an inner circumference of la" isto be strapped, the joint forming mechanism 55b is located below the central opening 1r: of the coilrand, so, itrwould be necessary to move the entire strapping head 55 radially outward of the coil so that the joint forming mechanism 55h is located in a region where a strap joint can be properly formed on the coil.V This radial movement of the strapping head 55 is accomplished by transporting the entire strapping apparatus i2, including the strapping head 55' and its supporting frame, on the wheels 44 which are supported and guided by the two tracks 45 and 46.

When the strapping apparatus 12 is relocated to accommodate a particular size coil, a special locking device is actuated to maintain the strapping apparatus 12 in a relatively iXed position. The locking device consists of a rod 78 whose upper end passes through an aperture 79 in a horizontal flange 86 secured to the upper end of the vertical frame member 51. Slightly up from the lower end of the rod 78 it passes through a slotted hole 81 in the upper flange 49a of the horizontal frame member 49. The lower end of the rod extends through another slotted hole 82 extending through the flange 49h of the horizontal frame member 49. The eXtreme lower end of the rod 78 is secured in a C-shaped locking shoe 83. This locking shoe $3 is provided with a groove 83a which has the upper flange of a channel member S4 passing through it. The channel member S4 is secured to the plate 47 which is ordinarily securely fastened to the iloor where the entire apparatus is used. The extreme upper end of the rod 73 is pivotally connected on a pin 8S to a yoke-shaped cam 85. The yoke-shaped cam S6 has a fiat surfaceV Sea and an opposite bulged surface 86b. The bulged surface Sb projects further from the pin 8S than does the flat surface 86a. A handle S7 is secured to the cam 86 and the purpose of the handle 87 is to rotate the cam 86 between positions where the bulged portion 86b or the flat surface 86m of the cam is in contact with a flat pad 80a.' on the upper surface of the llange Si). The length of the rod 78 is proportioned with respect to the location of the locking shoe 83 and the groove 83a of the locking shoe is of sufficient width that when the lever 87 is rotated to a position at 87a the flat surface 86a of the cam S6 is resting against the pad 30u. This places the rod 78 in its lowermost position where the walls of the groove 83a are frictionally clear of the upper llange of the channel 84. When the arm 87 is moved to a position as shown in bold outline in FIG. 4, the bulged portion Seb of the cam 86 is in contact with the pad 50a and this raises the rod 78 to its highest position. When in this position, the lower inner surface of the groove 83a of the locking shoe 83 is in frictional contact up against the lower surface of the upper liange of the channel 84. With this arrangement, the supporting frame carried by the wheels 44 of the strapping apparatus 12 is substantially located in position with respect to the rails 45 and 46.

With this arrangement, the frame supported by the wheels 44 is free to move relative to the lower end of the rod 7S by the amount of the length of the two slotted holes 81 and 82. The hole 79 in the iiange Si) is sui`n`ciently large that movement of the frame allows the rod 73 to assume an angle to the vertical. For example, if the strapping apparatus 12 was moved to the left as viewed inFIG. 4, the rod 78 would form an angle to the left of the vertical. To facilitate this angular movement and still insure a good grip of the locking shoe on the lower inner surface of the channel or guide 84, it is desirable to longitudinally curve the contacting surface 8311 of the shoe and provide the surface with sharpened protrusions. It should be observed that the rod '7S assumes the 'vertical position when its lower'end portions are resting against the left ends of the slotted holes 81 and 82. Therefore, these ends of the slotted holes prevent the rod 7SV from assuming an angle to the right of the vertical so that the frame cannot be rotated further to the right as viewed in FIG. 4 as long as the locking shoe S3 is frictionally engaged with the angle f-l. A tension spring S8 is secured at one end around the rod 7S and at its other end to a shaft 89* which is held secured in an apertured ear 99 protruding fromfthe frame member 49 by means of two threaded nuts 91. The purpose 0f the spring is to maintain the left ends holes S1 and S2 against the rod 7S ,to establish the relatively fixed referenced position for the strapping Amechanism 12. With what has been explained, it should be of the slotted apparent that the entire strapping apparatus can be moved to the left on its wheels 44 as the rod 78 tilts angularly to the left until the rod contacts the right end of either of the slotted holes 81 or 82. When this occurs, the spring 88 is stretched which urges the strapping apparatus back to a position where the rod 78 is again in contact with the left ends of the slotted holes 31 and 82,

The purpose of this limited movement of the strapping apparatus is to permit slight movement at the time when a strap loop 2 is being tensioned around a coil portion. By so doing, it has been found that the tension of the strap loop 2 is more or less equalized throughout its length around the coil portion so that loosening of the loop 2 does not occur to any substantial extent after the joint has been formed and the coil removed from strapping position. This loosening phenomenon is created by having uneven tension of the strap around the package. For example, in the ordinary situation, such as described for the apparatus disclosed herein, the leading end of the strap 14a is held securely by the gripping jaws 69 (FIG. 6). The enlarged strap loop as shown being held by the worker '13 in FIG. 1 is shrunk in size around a radial portion of the coil by reversing the feed direction of the strap which may be accomplished by reversing the feed Wheel 66 (FIG. 4) to withdraw the strap. As shown in FIG. 7, where a strap loop 2 is encircled around an annular portion of the coil 1, ordinarily the tension on the strap loop 2 will vary around the coil portion depending upon the corner conditions. If a pull is exerted in the direction of the arrow 92 in the magnitude of 100 pounds, a certain portion of the tension will be lost as the strap is pulled around the corner 93. Another portion of the tension will be lost around the corner 94 and additional amounts are successively lost around the last two corners 95 and 96, The result is that the tension in the region 147' of the strap is considerably less than the 10G pounds tension exerted in the direction of the arrow 92 on the supply strap end 14b. Usually, part of the reason for this difference in tension is because the gripping jaws 69 or another type gripping device used for gripping the leading strap end 14a is stationary relative to the longitudinal path of the strap 14. It has been found that, by allowing a little longitudinal shift of the strapping head 55, in the manner described, the tension is equalized between the region 14j of the strap and the region 14g of the strap while the tensioning occurs. The result of this is that greater over-all tension is provided in the strap loop 2 for a given tension force in the direction of the arrow 92 with no subsequent loosening of the strap loop after the strapping head 55 is removed. To more clearly illustrate what happens, first assume that the gripping jaws 69 hold the strap end 14a fixed. Then, assume that 100 pounds of tension force is applied in the direction of the arrow 92. Next, assume that pounds of tension is lost around each of the corners 93, 94, 95 and 96. With this condition, the tension in the strap between corners 93 and 94 would be 80 pounds, the tension between corners 94 and 95 would be 60 pounds, the tension between corners 95 and 96 would be 4() pounds and the tension between the corners 96 and the gripping jaws 69 'would be 2Gi pounds. Then, upon release of the strapping head from the strap loop 2 after the shear plate 71 cuts through the supply end 14b of the strap, the 2G pound tension force in the region 14f would be overcome by the 100 pound tension force of region 14g with a resultant loosening of the strap loop 2. Now, assume that the strapping head 55 is allowed to move as it does in this invention, and the gripping jaws 69 grip the leading strap end 14a. In this situation, assuming again that 2O pounds of tension are lost around each corner, there would be 100 pounds of tension in the region 14g, 80 pounds of tension between the corners 93 and 94 and 6G pounds of tension between the regions 94 and 95. But, between the corners 95 and 96, instead of 40 pounds of tension, there would be 80 pounds of tension and, in the region 1'41, instead of 20 pounds of tension there would be 10G pounds of tension. The iinal result of this is that, after the strap loop 2 is removed from the supply end of the strap 14, the tension established around the coil portion does not change since it is already equalized at pounds in both of the regions 14jc and 14g. Since no equalization occurs, there is no loosening of the strap 2 on the object.

This situation, where there is no loosening of the strap loop 2, is especially advantageous when strapping noncornpressible objects such as rather Solid, closely wound coils of metal strip, although not so significant when the object itself is compressible and is inherently resilient. in the case of non-compressible objects, the ability to provide a non-loosening loop 2 of strap may be the difference between success and failure when strapping such an object.

In summary, a coil is moved along the conveyor unit 5 to the conveyor 6 where it is positioned on the rollers 10 with the central opening 1a of the coil positioned above the strap end guide 4t). At this time the air or uid is admitted to the cylinder 32 to cause its piston rod 30 to elevate and raise the spider 19 and, consequently, raise the tapered rollers 15, 16 and 17 so that they ele'vate the coil 1 above the level of the rollers 10. This leaves the coil 1 supported by the tapered rollers. As previously mentioned, the locking shoe S3 can be adjusted -along the channel S4 to substantially lock the strapping apparatus 12 in any particular position along the rails 45 and 46, depending upon what size coil is to be strapped. Then the worker 13 causes the strap 14 to be fed endwise in the direction of the arrow 76 (FIG. 4) until it emerges from the front end of the strapping head S5. At this time, the strapping head 5S is pivoted downwardly by action of the air cylinder 61 which causes its piston rod 63 to retract. With the strapping head 55 pivoted downwardly, the strap 14 fed endwise is guided into the strap end guide 40 so that the strap follows along the surface 43a of the member 43 of the guide (FIGS. 4 and 7). The strap continues forward until its extreme end 14d contacts surface 4Gb where it is deflected downwardly to create an upwardly bowed portion 14e immediately behind the extrerne end 14d. This bowing creates the initial condition which starts an upward bulge of the strap. When the extreme end 14d rides completely down the surface 43h it contacts a stop surface 43C which arrests its endwise movement but allows the extreme end 14d to travel in a reverse direction down the sloped and curved surface 43C upon continued forward feeding of the strap 14 as the strap end pivots around the corner S14-f. As this occurs, the upward bulging tendency initially started at 14e continues with the creation of an upwardly bulged portion 14e. The strap 14 is continued to be fed until the upwardly bulge portion 14e is elevated high enough for the worker 13 to 'be able to manually grasp it as indicated'in dotted lines 13a in FIG. 1. When strapping annular objects it is desirable that this bulged portion 14C emerge through the central opening 1a of the coil 1. After the worker 13 grasps the bulged portion 14C he directs the extreme end 14d over and around the upper surface of the coil portion to be strapped and back beneath it so that the leading strap end 14a is above and in overlapping relationship with the supply strap end 14b. This leading strap end 14a must also pass through `a tubular seal 3 which is pre-positioned in the joint forming mechanism 55h and through which the supply strap end 14b has already been passed during the strap feeding operation. This relationship of the strap ends and the strapping mechanism is shown in FIG. 6. After this, the gripping jaws 69 are caused to grip the strap end 14a against a plate 70 where it is held while the feed wheel 66 is reversed and the strap iscaused to reverse in direction to remove the slack from the strap loop formed around the coil portion and, before or during the strap tensioning period, the piston rod 63 is extended by proper admission of air or other lluid to the cylinder 61 to cause the strapping head 55 to pivot upwardly against the coil 1. After all of the slack is removed, the strap loop 2 appears as shown in FIG. 7 in close contact with the coil 1. Then, the joint forming mechanism 55h is actuated to provide the interlocking type joint 4 between the tubularY metal seal 3 and the strap ends. After joint formation, the shear blade 71 is moved toward the plate '79 to shear off the strap loop 2 from the supply end of the strap 1li. After this occurs, the strapping head 55h is pivoted downwardly again by reason of retraction of the piston rod 63 of the cylinder 61. Sometime during this retraction or afterward, a seal 3 freshly formed over the anvil 73 is fed by the anvil '73 into position in the joint forming mechanism 55b in preparation for a new strapping cycle. The coil 1 is then rotated to align another of its radial portions with the strapping head 5S. This is accomplished by turning the crank 39 to cause rotation of the tapered rollers 15 and 16. Rotation is continued until proper alignment of the coil is achieved. After enough strap loops 2 are secured to the coil the piston rod 36 of the cylinder 32 is then caused to lower so that the spider 19 causes the tapered rollers 15, 16 and 17 to again be lowered 'beneath the level of the rollers 10. This releases the coil for free movement on the rollers and, in this manner, the strapping coil l1 can be pushed on to the conveyor unit 7 for subsequent handling and shipping.

Although the invention has been emphasized with respect to the use of a strapping apparatus having separate feed means and joint forming means, the strap end guide can be used with great facility when the strap is fed to the strap end guide merely by hand. The action is identical when the extreme strap end 14d reacts with the surfaces '43b and 43C of the strap end guide so that a bulged por- .tion 14C can be formed which is readily grasped by the worker. Also, the same principle can be used for strapping objects other than annular objects. It can be used for strapping elongated objects, such as perhaps pipes or tubes or other elongated pieces together. The elongated objects are pre-positioned in front of where the bulged portion would be formed. The bulge portion is then formed behind the objects and the worker 13 merely encircles the objects after the bulge portion is formed in the same manner as when strapping a portion of an annular object.

Although only a single embodiment of the invention has been shown and described, it should be understood that the invention can be modified in many different ways without departing from the true scope of the invention as defined by the appendant claims.

We claim:

l. In apparatus for securing a binder str-ap about portions of an annular object comprising, a frame for supporting the annular object, means for feeding a length of binder strap 'endwise belowl the annular object, a strap guide interposed in the path of travel of the binder strap being fed and located below the region of the central opening of the annular objectcsupported by the frame, said strap guide having both a downwardly sloping portion against which the end of 'the strap contacts as it is fed forward and an abutment for arresting longitudinal movement of the end of the strap, the slope of said portioncausing the strap Vend as the strap continues to be fed forward to be deflected downwardly into contact ,with said abutmentV to produce an upward bulge in the strap through the central opening of the annular object extendring to a level where it can beconveniently manually `grasped and encircled into a loop around a portion of the annular object.

2. In apparatus for securing `a binder strap around an object comprising, a frame for supporting the object, means for feeding a length of binder strap endwise below the object, a strap guide interposedV in the path of J travel of the binder strap being fedV and located below 12 the region of the object supported by the frame, said strap guide having both a downwardly sloping portion against which the end of the strap contacts as it is fed forward and an abutment for arresting longitudinal movement of the end of the strap, the slope of said portion causing the strap end as the strap continues to be fed forward to be deflected downwardly into contact with said abutment to produce an upward bulge in the strap extending to a level where it can be conveniently manually grasped and encircled into a loop around the object.

3. ln apparatus for securing a binder strap around an object comprising, a support for an object, a strap guide located adjacent to said support and aligned to receive the leading end of a length of strap fed endwise to it, said strap guide having means to deflect the strap end into a curved path to provide it with a bulge while the strap is fed endwise, said strap guide also having a stop means for arresting the forward movement of the strap end but not the strap proper to thereby increase the size of the bulge to make the bulge available for manual grasping so that the strap end can be manually encircled in a loop around the object on the support, and means adjacent to said guide for securing the loop onto the object.

4. The apparatus as defined byclaim l characterized by, and means adjacent to said guide for securing the loop onto the object.

5. The apparatus as defined by claim 2 characterized by, and means adjacent to said guide for securing the loop onto the object.

6. The method of making a binder strap available for encircling it around an object comprising, feeding a binder strap endwise in a rectilinear path across at least a portion of the object, deflecting the strap end into a downwardly curved path to provide it with an upward bulge beyond said portion of the object, then arresting the endwise movement of the strap end while continuing the forward feeding movement of the strap proper to thereby increase the size of the upward bulge to one which can be manipulated around said portion of the object.

7. The method of making a binder strap available for encircling it -around at least a portion of an object comprising, feeding a binder strap endwise across at least a portion of the object, dcflecting the strap end into a curved path to provide it with a bulge beyond said portion of the object, then arresting the endwise movement of the strap end while continuing the endwise feeding Vmovement of the strap to thereby increase the size of the bulge to one which can be manipulated around said portion of the object.

8. The method of making a binder strap available for encircling it around a radial portion of an annular object comprising, feeding a binder strap endwise below the annular object until the strap end passes beneath the central opening of the annular object, then arresting the endwise movement of the strap end while continuing the endwise feeding movement of the strap and thereby causing the strap end to bulge -upward through the central opening where it can be conveniently manually grasped and encircled around the radial portion of the annular object. t

9. The method of securing a binder strap around an annular object comprising, supporting the annular ob ject with its axis extending approximately vertical, feeding a binder strap endwise beneath and radially of the annular object, deflecting the' strap end into a downwardly curved path in a region ybelow the central opening of the annular object to provide the strap with an upward bulge, then arresting the endwise movement of the strapV end while continuing the endwise movement of the strap to thereby causeV the bulge to enlarge upwardly to where it can be conveniently manually grasped, then manually grasping the bulge and encircling the strap end into a loop radially around a portion of the annular object, and securing the loop onto the annular object.

10. Apparatus for securing a binder strap around an object comprising, a strapping station where an object to be strapped lis positioned, a strapping head mounted on a carriage movable to any of a plurality of locations at said strapping station, bias means for biasing said carriage at one of said locations, and means allowing said bias means to be overcome by a force applied to said carriage and allow movement of said carriage relative to said one location in response to said force applied.

1l. Apparatus as dened by claim 10 characterized by, stop means being provided between the bias means and the carriage `for limiting the movement of the carriage relative to the bias means.

l2. Apparatus for securing a binder strap around an object comprising, a strapping station where an object to be strapped is positioned, a carriage provided with wheels mounted on rails for movement to any of a plurality of locations at said strapping station, a strapping head mounted on and .movable with said carriage, a locking shoe mounted on a rod pivotally supported by said carriage, said locking shoe being releasably engageable with a guide at any of said locations of said carriage, movement of the carriage along said rails causing said rod to pivot angularly with respect to the carriage when said locking shoe is engaged with said guide.

13. Apparatus as deiined by claim 12 characterized by, and stop means being provided on the carriage which contacts said rod to limit its pivotal movement and thereby limit the movement of the carriage along said rails.

14. Apparatus for securing a binder strap around an object comprising, a strapping station where an object to be strapped is positioned, a carriage mounted for movement to any of aplurality of locations at said strapping station, a strapping head mounted on and movable with said carriage, a locking shoe movably mounted on said carriage and ordinarily held by resilient means against a rst stop on said carriage and also releasably engageable with a fixed guide extending in the path of movement of said carriage, said carriage being freely movable when said locking shoe is disengaged from said xed guide, but restrained from movement in one of said locations by the resilient force of said resilient means when said locking shoe is engaged with said xed guide, the restraint from movement of the carriage being overcome upon the application of suiiicient `force against the carriage to thereby overcome the resilient force of said resilient means and cause movement of the carriage from said one location relative to the locking shoe.

l5. Apparatus as deiinedby claim 14 characterized by, and a second stop on said carriage engagea-ble by said locking shoe for limiting the movement of the carriage relative to the locking shoe.

16. Apparatus for securing a binder strap around an object comprising, a strapping station where an object to be strapped is positioned, a carriage mounted for movement to any of a plurality of locations at said strapping station, a strapping head mounted on said carriage and movable therewith, said strapping head having a gripper for gripping the leading end of a length of strap encircled into a loop about the object positioned at the strapping station with the leading end of the strap overlapping the supply end of the strap, said strapping head also having tension means for withdrawing the supply end of the length of strap relative to said leading end to tension the loop onto the object, a locking shoe movably mounted on said carriage and also releasably engageable with a fixed guide extending in the path of movement of said carriage, said carriage being freely movable when said locking shoe is disengaged from said iixed guide, but restrained from movement when in one of said locations by the resilient force of said resilient means when said locking shoe is engaged with said Xed guide, said tension means being capable of tensioning said loop sufficiently so that the tension force developed in said loop is sucient to overcome said resilient force of said resilient means to thereby cause movement of the carriage from said one location relative to the shoe for the purpose of equalizing the tensions developed in the overlapping regions of the supply and leading ends ofthe loop.

17. The apparatus as defined in claim 16 characterized by, and stop means on said carriage for limiting the movement of said carriage relative to the locking shoe when the locking shoe is engaged with said Xed guide.

18. Apparatus for securing a binder strap around an object comprising, a strapping station where an object to be strapped is positioned, a strapping head mounted on a carriage movable to any of a plurality of locations at said strapping station, said strapping head having a gripper for gripping the leading end of a length of strap encircled into a loop about the object positioned at said strapping station with the lleading and supply ends of the strap eX- tending in overlappingrelationship, said strapping head also having tension means for withdrawing the supply end of the length of strap relative to said leading end to tension the loop onto the object, bias means for biasing said carriage at one of said locations, said tension means being capable of tensioning said Ilength of strap sufficiently to develop a tension force in the strap large enough to overcome said bias means to thereby cause movement of the carriage from said one location and equalize the tensions developed in the overlapping regions `of the supply and leading ends of the strap.

19. The apparatus as dened in claim 18 characterized by, and stop means on said carriage for limiting movement of said carriage when the carriage is biased at said one location.

20. In apparatus for securing a binder strap around an object comprising, a trarne for supporting an object, a strap guide located adjacent the region of the supported object and aligned to receive the leading end of a length of strap fed endwise to it, said strap guide having an abutment against which the strap end is rst deected and shaped into a bow and then arrested in its forward motion which causes said bow to increase in size as the feeding of the strap continues, said abutment having two regions of contact against which the strap end reacts as the lbow is increased in size to thereby create a gripping action on the strap end which prevents displacement of the strap end from the region of said abutment.

21. The apparatus as defined by claim 2 characterized by, said strap guide also having two spaced apart regions of contact in the vicinity of said abutment against which the strap end reacts as said bulge is formed to thereby create a gripping action on the strap end which prevents displacement of the strap end from the region of said abutment.

22. In apparatus for securing a binder strap around an object comprising, a support, a strap guide located adjacent to said support, and aligned to receive the leading end of a length of strap fed endwise to it, said strap `guide having means to deflect the strap end into a curved path to provide it with a bulge while the strap is fed endwise, said strap guide also having a stop means for arresting the forward movement of the strap end but not of the strap proper to thereby increase the size of the bulge, said strap guide also having two spaced apart regions of contact in the vicinity of the two mentioned means against which the strap end reacts as the bulge increases in size to thereby create a gripping action on the strap end which prevents displacement of the strap end from the region of said abutment.

23. In apparatus for securing a binder strap around an object comprising, a support for an object, a strap guide located adjacent to said support and aligned to receive the leading end of a length of strap fed endwise to it, said strap guide having deection means to deect the strap end into a curved path to provide it with a bulge while the strap is fed endwise, said strap guide also having a stop means for arresting the forward movement ofthe strap end but not the strap proper to thereby increase the size of the bulge to make the bulge available for manual grasp-ing so that the strap end can be manually encircled in a loop around the object on the support, said strap guide also having two spaced apart regions of contact in the vicinity of the deection means and the stop means against which the strap end reacts as the bulge increases in size to thereby create a gripping action on the strap end Vwhich prevents displacement of the strap end from the region of said abutment. Y

24. The method of making a binder strap available for encircling it around an object comprising, feeding a binder strap endwise in a rectilinear path, `deliecting the strap end into a downwardly curved path to provide an upward bulge in the strap immediately behind the strap end, arresting the endwise movement of the strap end while continuing the endwise feeding movement of the strap proper to thereby increase the upward bulge, then allowing the strap end to rotate in response to the forces resulting from the formation of the upward bulge and then restraining the rotational movement of the strap end to create a gripping pressure for gripping the strap end and ypreventing its further displacement.

25. In apparatus for securing a binder strap around an object comprising, a frame for supporting an object at a strapping station, a strap guide located adjacent the region of the supported objectand aligned to receive the leading end of a length of strap fed endwise to it, said strap guide having an abutment against which the strap end is arrested in its forward motion, said guide being shaped to deflect the strap end and shape it into a bow which is caused to increase in size as the feeding of the strap continues, a strapping -head mounted on a carriage movable to any of a plurality of locations at said strapping station to accommodate ldifferent positions and sizes of objects located at the strapping station, said strapping head having a strap end gripper for gripping the leading end of the strap and a strap feed means for feeding a length of strap endwise into said strap guide and for reverse feeding of said strap to tension it after it has been grasped when in the shape of said bow and encircled in a loop about an object with its leading end gripped by said gripper, bias means for biasing said carriage at one of said locations, and means allowing said bias means to be overcome by the force developed in the strap while it is tensioned to allow movement of said carriage relative to said one location in response to said force.

References Cited in the file of this patent UNITED STATES PATENTS MacChesney Mar. l0, 1936 12,688,482 Boblit Sept. 7, 1954

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