US3834297A

US3834297A - Bale strapping system

Info

Publication number: US3834297A
Application number: US00253125A
Authority: US
Inventors: G Huson
Original assignee: Signode Corp
Current assignee: Signode Corp
Priority date: 1972-05-15
Filing date: 1972-05-15
Publication date: 1974-09-10
Anticipated expiration: 1991-09-10
Also published as: SU500744A3; CA987225A; JPS5126120B2; FR2184624A1; DE2324293C3; DE2324293B2; JPS4942494A; DE2324293A1; GB1358148A; FR2184624B1

Abstract

A bale of material such as cotton is held compressed along a vertical axes at a packaging station in a press where a strapping device at one side of the press serially feeds a plurality of straps around the bale at respective strapping locations spaced transversely along the bale sides tensioning each into engagement with the bale and joining each by a seal at one side of the bale. A strap shifting apparatus is mounted at the other side of the packaging station to a transversely movable vertical support. It includes a back-up member horizontally extending to the adjacent bale, and a transversely-extending portion alongside the bale side having a surface thereon facing away from the bale towards the support and which is engaged by a strap when tensioned. Either an arm carrying a wheel at one end and pivoted on the support near the other, or an extendable plunger carried in a cylinder at one end and having a gripping surface at the other end, then moves to compress the strap against the back-up strap surface. In the former, the wheel is then driven to cause the strap to shift, and in the latter, both anvil and plunger are mounted upon a carriage movably carried upon the support, and the carriage is driven vertically along the support to thereby move the strap, and shift the seal from the side to the bottom of the bale. The strap shifting apparatus may then be transversely moved to disengage from the strap and to be repositioned at another strapping location, and the operation repeated.

Description

[ Sept. 10, 1974 United States Patent 1191 Huson BALE STRAPPING SYSTEM [75] Inventor: Gale Huson, Glenview, Ill.

[73] Assignee: Signode Corporation, Glenview, Ill.

[22] Filed: May 15, 1972 [21] Appl. No.: 253,125

[52] US. Cl 100/3, 100/26, 100/30 [51] Int. Cl B65b 13/04 [58] Field of Search 100/1, 2, 3, 8, 14, 25, 100/26, 29, 30, 32, 33, 31

[56] References Cited UNITED STATES PATENTS 3,224,363 12/1965 Talbot 100/3 3,521,550 7/1970 Van Doom et al 100/26 Primary Examiner-Billy J. Wilhite [57] ABSTRACT A bale of material such as cotton is held compressed along a vertical axes at a packaging station in a press where a strapping device at one side of the press serially feeds a plurality of straps around the bale at respective strapping locations spaced transversely along the bale sides tensioning each into engagement with the bale and joining each by a seal at one side of the bale. A strap shifting apparatus is mounted at the other side of the packaging station to a transversely movable vertical support. It includes a back-up member horizontally extending to the adjacent bale, and a transversely-extending portion alongside the bale side having a surface thereon facing away from the bale towards the support and which is engaged by a strap when tensioned. Either an arm carrying a wheel at one end and pivoted on the support near the other, or an extendable plunger carried in a cylinder at one end and having a gripping surface at the other end, then moves to compress the strap against the back-up strap surface. In the former, the wheel is then driven to cause the strap to shift, and in the latter, both anvil and plunger are mounted upon a carriage movably carried upon the support, and the carriage is driven vertically along the support to thereby move the strap, and shift the seal from the side to the bottom of the bale. The strap shifting apparatus may then be transversely moved to disengage from the strap and to be repositioned at another strapping location, and the operation repeated.

39 Claims, 8 Drawing Figures BALE STRAPPING SYSTEM BACKGROUND OF THE INVENTION This invention relates to a method and apparatus for packaging a bale or the like of compressible material such as cotton or man-made fibers with straps or the like while the same are held under compression in a baling press. More particularly, it concerns an improvement in such packaging for producing a strapped bale of superior strength and size standardization.

A persistent serious problem in the production of bales of compressible material such as cotton or other fibers has been the breakage of the joints of the straps used to hold together the bales after compression into a compact size despite the uniformly high strength of both the joint seals and straps, due to factors beyond the control of the strap or joint seal manufacturers. One such factor is that the typical baling press is capable of compressing widely varying quantities of material into the same standard compressed size, so that the force exerted by the compressed bale against its confining straps will vary and be greater than expected at times due to the possibility that extra material over and above the usual was caused to be compressed by the press.

A common solution to the problem of strap breakage has been to minimize the force exerted by the bale by allowing slack so that the straps are not as tight as they might otherwise be. This is, of course, effective in lowering the stress on the strap and joint, but aggravates another common problem in the production of bales, that of variations in the volumetric size of the bales because of the unpredictable side expansion which the inducement of slack will allow. The nonstandard oversized bales which this expedient tends to produce gives rise to problems in satisfying industry and government regulations regarding size standards and in shipping.

Another expedient to reduce the breakage of straps has been to join the strap at the top surface of the bale instead of at the sides of the bale, where it is usually fabricated. The top and bottom ends of the bale are held under compressive load by members of the baling press in either case. It has been found the joints on either of the top or bottom bale surfaces are subjected to smaller tensile forces than they would be in a side bale location, where the joint lies in the direction of the bale compression. But any top-sealing machinery for this purpose must be constructed with sufficient strength to withstand the impact and the compressive forces of bale compaction. Such strengthened construction, of course, inevitably has the disadvantage that it is expensive.

In an effort to avoid such expense while attaining similar benefits, it has been attempted to manually move the joint seals to the bottom or top of the bale. However, the disadvantages are the joint seals inevitably have corners and protrusions which will snag at the bale comers, particularly in view of the limitations on the amount of force exertable by hand-labor expedients. Furthermore, much greater than average slack must be left in the straps because of such limitations. Thus, many of the disadvantages of simply allowing the slack to be introduced to cut the tensile force exerted upon the straps are thereby re-introduced.

SUMMARY OF THE INVENTION Accordingly, a method and apparatus for strapping a bale or the like by automatic means while maintaining high strap tension has been provided. This method includes providing a supply of compressible material at a strapping station, compacting the compressible material to form a bale, and feeding a length of strap around the bale to form a loop including overlapping strap por- 0 tions. Unlike previous methods, this method also includes constricting the strap loop into tight binding engagement with at least one side of the bale, and subsequent loop constricting step, forming a closure in the overlapping strap portions at one side of the bale and the moving the closure with its tightly constricted strap loop from one side of the bale to the bottom thereof.

Also provided is a strap shifting apparatus for use with bale strapping apparatus. Such apparatus includes support means and a back-up member carried by the support means and positionable adjacent a bale, the back-up member having a surface adapted to engage a strap positioned around the bale and retained in a loop by a seal at one side of the bale. Further provided is a pressure applying member together with means mounting the pressure applying member upon said support means for movement between a clearance position enabling the strap to be positioned around the bale and a strap compressing position adjacent the back-up member surface which is adapted to engage the strap. Finally provided are means for applying a motive force to the pressure applying member when the pressure applying member is in the strap compressing position for shifting the seal from one side of the bale to an end thereof.

BRIEF DESCRIPTION OF THE SEVERAL VIEW OF THE DRAWINGS FIG. 1 is a side elevational view, partially in section, of a typical baling press and an inverted U-shaped frame supported upon such press and mounting a bale strapping means on the right leg thereof, and a strap shifting apparatus according to the invention on the other leg thereof, showing the manner of passage of a strap about a bale held within the press, with the other loop indicating its initial position, and the inner loop indicating its position upon tensioning;

FIG. 2 is a fragmentary side elevational view, similar to FIG. 1, and illustrating the position of the strap after it has been acted upon by shifting apparatus of the invention;

FIG. 3 is an enlarged sectional view taken along line 3-3 of FIG. 2, showing the bulging of the area of the bale about a strap;

FIG. 4 is an enlarged side elevational view of the shifting apparatus shown in FIGS. 1 and 2 immediately prior to the engagement of a strap by the shifting apparatus for enabling movement of the strap by the apparatus;

FIG. 5 is a fragmentary side elevational view, similar to FIG. 4, with certain portions broken away for clarity of illustration and showing the shifting apparatus in engagement with a strap prior to the shifting of such strap by the apparatus;

FIG. 6 is a top plan view of the shifting apparatus taken along line 6-6 of FIG. 5;

FIG. 7 is a side elevational view similar to FIG. 1, and illustrating an alternative embodiment of the shifting apparatus of the invention in its initial position during the feeding and tensioning of the strap about the bale; and

FIG. 8 is a fragmentary side elevational view similar to FIG. 7, and showing the position of the strap subsequent to the operation of the shifting apparatus of FIG. 7.

DETAILED DESCRIPTION While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail a preferred embodiment of the invention and a modification thereof, with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the embodiments illustrated. The scope of the inventon will be pointed out in the appended claims.

A complete bale forming and packaging system, including the strap shifting apparatus of the invention, includes a typical baling press 11 which forms a highly compressed bale 12 from compressible material such as cotton, an upstanding U-shaped support 20 secured to the frame of the press 11 and having two parallel

vertical legs

21 and 22 on either side of the press and spaced therefrom, as well as a cross member 23 extending over the press, and from which the vertical legs extend downwardly. The system also includes a strapping device 40 and a shifting apparatus 30 carried respectively on

legs

21 and 22.

The typical high density press 11 includes opposed upper and

lower platens

13 and 14 mounted in a frame 15 and having generally square or rectangular working surfaces 16 and 17 respectively, facing the top and bottom ends of bale 12. Platen 13 is fixed in a stationary position, while lower platen 14 is mounted within the press for movement in a downward vertical direction toward an intake position allowing the material to be baled to be deposited between the platens, and upwardly into a compression position wherein the material is compressed between

platens

13 and 14 into a bale. FIGS. 1 and 2, and 7 and 8 illustrate the compression position; the vertical separation distance between platens in the compression position, which is of course generally the height of the finished bale, is much less than the operation distance between the platens in the intake position.

The press 11 also includes walls (bit shown) enclosing the region between the platens and retaining the material during compression, with the walls enclosing the sides of the bale 12

adjacent legs

21 and 22 being removed subsequent to compression of the bale to provide access to the

corresponding sides

8 and 9 of bale l2 and platens l3 and 14. Thus a generally rectangular, highly-compressed bale is formed between the opposed platens within press 11 and is held therein at what then becomes a packaging station to await the operation of strapping device 40. Such a bale has an axis of compression in the direction of movement of platen'14, which in this case is the vertical direction. It should be noted that although the press is herein described as upright, the invention is equally adaptable to a press operating horizontally; or a vertical press wherein platen 14 is fixed, and 13 movable.

U-shaped support is positioned to enclose the press 11 within its members, as stated. It is supported on press frame 15 by

track members

23 and 24 respec- -tively secured to opposite sides of frame portion 15 ad- 5

jacent legs

21 and 22, respectively, and extending longitudinally in the transverse sense, that is, into and out of the plane of the drawings, (FIGS. 1, 2, 7 and 8) together with roller means 25 and 26 mounted to

legs

21 and 22. Support 20 is then movable in such transverse direction perpendicular to the axis of the bale compression, and parallel to bale

sides

8 and 9 and those of press 11, to bring both the

legs

21 and 22 together to any one of various transverse strapping locations adjacent the

accessible sides

8 and 9.

Working surfaces 16 and 17 of platens l3 and 14 are provided with a respective set of parallel opposed grooves or channels open toward the bale ends spaced transversely from each other, one each of which is shown respectively at 18 and 19 extending across the surfaces from one access side to the other end. The number of channels in both sets is the same, and their position and spacing matching the number and transverse spacing of the

channels

18 and 19 define the number and location of the strapping locations along the

sides

8 and 9 of bale 12. These horizontal channels, together with other generally vertical ones to be described, serve as part of a system of guides extending around the bale for the guiding of strap lengths used to package the compressed bale. The configuration of these vertical channels is well known to those skilled in the art, and may be of the type described in detail in US. Pat. No. 3,220,337 to Goland and assigned to the same assignee as the present application. A cross section of such a vertical channel 65 is illustrated in FIG. 6. A pair of generally flat bars 5 having transversely directed lips 6 are held in vertically extending, parallel spaced relationship with the lips extending toward each other, thereby defining one portion 7 of the strap guidewy therebetween. At least one of the bars is resiliently biased to be transversely movable as indicated by the dotted line, so that a strap within the guideway portion may be pulled out toward the bale.

All of the guide channels of the system except those of

platen

13 and 14 are constructed similarly to channel 65. A strap 28, which ray be of metal or nonmetallic flexible material such as nylon, together with strapping means 40 which feeds strap 28 into the system of guides and thereafter tensions and fastens it, is shown in FIGS. 1, 2, 7 and 8. Strapping device 40, which may be of the type described in greater detail in US. Pat. No. 3,493,014 to Orban et al. and assigned to the same assignee as the present application, is secured to leg 21 generally midway between

platens

13 and 14 in the compressed position, and adjacent the bale side 8, but spaced therefrom by a small distance which is a fraction of the width of the platens. Apparatus 40 includes an enclosure 41, a strap feeding and tensioning device 42 in the lower portion of the enclosure, a seal feeding magazine 43 in the upper portion of the enclosure 41, a seal crimping mechanism 44 positioned intermediate the former elements and cooperating therewith at a seal crimping station 45 of front strap overlap guide member 46 positioned immediately adjacent bale 12 and having a vertical strap guide channel 51 constructed similarly to channel 65, opening toward bale side 8. The feeding and tensioning device 42 comprises a pair of opposed rollers 48 and 49 at the lower outside end of the enclosure 41 communicating with the input of a strap guide channel 50 curving upwardly toward an output adjacent bale side 8 and station 45, with the output of the curved channel 50 aligned with the lower end of channel 51 of overlap guide 46.

Also secured on leg 21 immediately below strapping device 40 is an auxiliary strap guide member 52 having a curved inner surface extending generally from the side of platen 14 corresponding to bale side 8 up to a point adjacent the output of channel 50. Within the surface, member 52 is provided with a guide channel 53 opening toward this surface and the bale, and whose lower end is positioned to communicate with any one of the guide channels 17 of lower platen 14, the choice depending on the position of frame 20 along the

tracks

23 and 24. The upper end of the channel 53 is positioned immediately adjacent the output end of channel 50 and together with that channel is in communication with the lower end of channel 51 of overlap guide 46. Another auxiliary strap guide 56 similar to guide 52 is secured to leg 21 immediately above device 40 and extends between it and upper platen 13. A guide member 56 has an inner curved surface extending generally from the side of platen 13 corresponding to bale side 8 around to a point adjacent the upper end of overlap guide 46. A strap guide channel 57 is provided within the surface, open toward the bale and having an upper end positioned to communicate with any of the channels 18 of platen 13, the choice depending on the position of frame 20 along

tracks

23 and 24. The channel 57 also has a lower end communicating with the upper end of the strap guide channel 51 of overlap guide 46.

On the opposite side 9 of the bale 12 is positioned a second similar pair of

auxiliary guide members

61 and 62 secured to the opposite support leg 22 respectively above and below shifting apparatus 30, which is itself positioned on leg 22 approximately midway between

platens

13 and 14 in their compression position. Both the

guide members

61 and 62 are similar to

members

51 and 52, and have respective

curved channels

63 and 64 opening toward the bale and each communicating with a channel of the platens and ultimately with guides 52 and 53, as well as respectively opening toward upper and lower ends of a strap guide channel 65 whose construction has been previously described, on an innermost bale-facing surface of the shifting apparatus 30.

When frame 20 is transversely moved to any one of the strapping locations corresponding to two opposed ones of the channel sets 18 and 19 of the platens, these two channels, together with the

auxiliary guide channels

52, 53, 61 and 62 and the channels 65 and 51 respectively of the shifting apparatus and strapping device form a closed path adjacent to bale 12 but everywhere spaced therefrom, illustrated by an outer

circumferential loop

58 and 58, respectively in FIGS. 1 and 7. As can be seen, the horizontal portions of the loop within

channels

18 and 19 lie in a direction perpendicular to the axis of bale compression, while the vertical portions of the strap loop within guides 46 and 65 lie in the direction of the compression axis. Loop 58 is the position initially assumed by the strap length, due to its resilient tendency to expand outwardly away from bale 12, as it is fed from a supply (not shown) by the rollers 48 and 49 upwardly through

channels

50 and 51 and from the lower to upper end of channel 66 of overlap guide 46 through guide 56, one of the channels 18 of platen l3, and around the bale through the remaining communicating channels until reaching auxiliary guide 52. After passing upwardly through guide 52, the strap length emerges overlapping on the bale side 8, the length of strap passing from channels to 51, and continuing in such attitude well into overlap guide 42 just beyond seal crimping station 45. At this point, a gripper (not shown) is actuated to hold the free end of the strap, while rollers 48 and 49 reverse to exert tension on the strap loop 58, causing the strap to leave all of the guide channels on all sides of the bale and to be constricted against bale 12 in tight binding engagement, except at

sides

8 and 9, as illustrated by the innermost loop 59 and 59', respectively in FIGS. 1 and 7.

At side 8, the strap is of course held within station 45, and at the bottom corner, it is held away from bale 12 by a roller 68, which is supported on leg 21 by a horizontally-extending strut 69 secured to leg 21 below device 40 and to one side of auxiliary guide 52. At side 9, the strap is held slightly away from bale 12 by a transversely extending back-up or anvil member, comprising an arm 32 and an anvil 34 held closely adjacent side 9, as will be described below. Device 43 then feeds a seal 67 downwardly to supply crimping mechanism 44, which then crimps the seal 67 around the overlapped strap portions at station 45, as shown in FIG. 3. Thereafter, the strap is severed from the portion remaining in channel 50 by a suitable cutting mechanism (not shown), and the sealed strap is released so that the completed strap loop 90 is free of the apparatus 40, as shown in FIGS. 2 and 8. Such a completed strap loop 90 may of course be installed by many different types of devices, strapping device 40 being only an exemplary one thereof. Any means will serve which installs the strap about this bale 12 as shown by loop 90, in tight engagement with the bale, as well as with roller 68 and anvil 34.

The back-up member is a part of the complete strap shifting apparatus 30, which may be seen in FIG. 1 and particularly in FIG. 2 in operative relationship within the complete packaging system; FIGS. 4 through 6 show the details of the apparatus to best advantage. The apparatus has a longitudinal frame 31 vertically secured along leg 22 midway between the platens in their compressed position and to which is secured strap guideway on the frame surface facing bale side 9, as noted earlier. A support 31a carrying pivot means 31b is secured to the lowermost end of frame 31 and extends horizontally and to one side of frame 31 toward bale side 9. A horizontally-fixed arm 32 is secured to frame 31 by a transversely extending support 32a (see FIG. 6) at a point between leg 22 and guideway 65 extending outwardly alongside frame 31 along bale side 9, with the one of bars 5 of channel 65 adjacent arm 32 being provided with an opening for support 32a. Carried at the end of arm 32 remote from frame 31 is anvil 34 having a horizontally-extending portion 34a by which it is secured to arm 32, and a portion 34b extending transversely generally parallel to bale side 9, but perpendicular to leg 22, which has a curved strapengaging surface 35 opposite the side of the portion which faces the bale. At a point on portion 34g adjacent portion 34b, a bolt 73 mounts anvil 34 to arm 32 to allow anvil 34 to be pivoted about that bolt toward and away from bale 12.

At the end of portion 34a opposite portion 34b, a lock bolt arrangement 74 adjusts and fixes anvil 34 in any of a range of positions toward bale 12 and away from strap loop 90, or away from bale 12 and toward strap loop 90. The arrangement includes a boss 112 on portion 34a at the lowermost corner thereof opposite portion 34b and extending transversely under arm 32. Boss 112 is provided with a vertical threaded passageway receiving threaded rod 1 13, so that one end is positioned against arm 32, with the other end carrying lock nut 114. Thus, adjustment of rod 113 and nut 114 posi tions the anvil by pivoting it with respect to arm 32. The adjustment is then locked with the aid of a bolt 1 15 passed transversely through a slot 116 in portion 34 above boss 1 l2 and threaded into arm 32. Such adjustment determines not only the spacing of anvil 34 from bale side 9, but also the degree of proximity of surface 35, together with the portion of strap loop 90 which it engages, to the remainder of the strap shifting apparatus 30.

The apparatus 30 further includes a movable arm 36 carrying a gripping means 30a at one end positionable adjacent surface 35 so that a portion of the strap loop 90 is captured between the surface and means 30a, and the position adjustment of anvil 34 and surface 35 effects the degree of gripping force upon the captured strap portion. The movable arm 36 is movably supported at the junction of arm 32 and frame 31 about a pivot 76 supported by support 32a extending transversely from arm 32 and frame 31, as is best appreciated from FIG. 6. The arm 36 is thus movable from a vertically upraised position illustrated in FIG. 4 to a generally horizontal position alongside arm 32, as illustrated in FIG. 5, in which the end carrying gripping means 30a is adjacent the strap engaging surface 35 of the anvil 34. From the end of the movable arm 36 adjacent to the pivot 76 extends an offset portion 37 to which is pivotally connected the upper end of a plunger rod 71. This lower end of rod 71 is carried within the upper lead end of a pneumatic cylinder 77, mounted vertically alongside frame 31, with its lower head and connected by pivot means 31b to support 31a. Actuation of the cylinder 77 will cause plunger rod 71 to extend and drive portion 37 upwardly and thereby pivot the remainder of the arm down about pivot 76 toward its horizontal attitude so that the opposite end of arm 36 opposite portion 37 is brought immediately adjacent anvil 34.

The gripping means 30a is provided at the end of arm 36 opposite protruding portion 37 and includes a feed wheel 38 roughened or knurled about is periphery and riding on a transverse axle 39 mounted at one of its ends to a side of arm 36. A conventional air motor 78 is secured in fixed spatial relationship with respect to arm 31 by suitable support structure, and is geared to the feed wheel 38 to drive the wheel when the arm 36 is in its anvil-adjacent horizontal position. In the vertically raised position of arm 36 the wheel end of arm 36 as well as other associated arm elements are positioned adjacent leg 22, back to guide channel 65 as well as guide channel 63 of auxiliary guide 61. The verticallyupraised position of arm 36 is maintained by cylinder 77 when unactivated, plunger rod 71 then being in a retracted position. This is the position maintained by arm 36 during the strap feeding operation of device 40, so that the shifting apparatus does not interfere with the action of the strap guide channels in forming a strap loop about the bale. However, anvil 34 is maintained in position adjacent the bale throughout; stationary arm 32 and anvil 34 do not interfere with the strap feeding operation despite their outwardly extending position since, as can be seen from FIG. 6 particularly, arm 32 is positioned to one side of guideway 65, and thus of the path of loop 29. As the strap is tensioned and leaves the guide channels to engage the bale, however, it engages surface 35 of anvil 34 on bale side 9, since the anvil extends transversely along the bale side 9 to a position in the plane of guideway 65.

Upon completion of the fastening of the strap loop, the shifting apparatus is put into operation by actuating the cylinder 77 to cause the arm 36 to assume its horizontal position; see FIG. 5. In this position, feed wheel 38 captures a portion of the strap loop between itself and anvil surface 35 with a strong applied pressure due to the force exerted by cylinder 77 through the extended rod 71 upon offset portion 37. With a portion of the strap thus gripped, motor 78 then is actuated to rotate the feed wheel 38 counterclockwise to drive the strap loop 90 in a clockwise direction. Roller 68 aids the seal in its passage around the lower corner of bale side 8 and prevents its possible snagging on the material of the bale. When seal 67 is positioned on the lower end of the bale which is in contact with surface 17 of lower platen 14, motor 78 is stopped and cylinder 77 returns arm 36 to its vertically upright position. The operation of motor 78 may be manually controlled, or alternatively, a timer may be used, set to actuate motor 78 for a fixed time interval. This time interval is easily determined, since a fixed spatial relationship exists between the initial location of the seal on bale side 8 and the position at the bottom of the bale midway between

bale sides

8 and 9 to which it is moved.

Of course, the rotation of motor 78 and wheel 38 might be reversed to instead position the seal 67 at the top of the bale. However, such a top position for the joint has been found inexpedient in practice, given the manner and direction in which the strapping apparatus 40 operates. It will be recalled that apparatus 40 feeds the strap loop 58 across side 8, the top of the bale, across side 9, and across the bottom of the bale until overlap occurs at bale side 8. After seal 67 has been affixed, some of the overlap results in a short free end 90a (see FIG. 1) projecting upwardly from the seal and lying inwardly of the closed loop. The free end 90a causes no problems when the seal is moved as described above; however if instead the seal 67 were moved upwardly, the free end 90a would inevitably snag in the material of the bale.

FIGS. 7 and 8 show a bale forming and packaging system which is quite similar to that just described except that a variant strap shifting apparatus is employed which achieves comparable results. Included is a similar press 11 having opposed upper and lower platens 13 and 14', a strapping device 40' together with adjacent auxiliary strap guides 51' and 52 respectively above and below device 40 and positioned between it and platens 13' and 14' when the latter are in their compression position as in FIG. 7. The strap shifting apparatus 80, also mounted adjacent bale side 9 to a leg 22 which is part of a support frame similar to frame 20, includes a longitudinal frame carriage 81 carrying the remainder of the apparatus, and which is slidably mounted upon leg 22 so as to be movable in the vertical direction along leg 22'.

The carriage includes a strap guide channel 92 on its inner surface nearly as long as the height of bale 12 open to bale side 9, and an auxiliary strap guide member 61' carrying a strap guide channel 63' which curves from the upper end of channel 92 to an edge of platen 13'. Both platens are provided with respctive sets 18' and 19 of horizontally lying channels parallel and spaced transversely from each other to provide strapping locations as in the previously-described figures, and with the proper transverse positioning of leg 22', the strap guide channels 63 may be communicably aligned with one of the channels of platen 13. Likewise, the carriage 81 includes at its lowermost end a strap guide member 82 having therein a curved guide channel 64' communicating with the lower end of channel 92 and one of the guide channels of platen 14 when the latter is in its compression position as in FIG. 7, and when leg 22 is in the proper transverse position. The channels of the various elements thus establish a continuous strap guideway reaching completely around the bale and spaced therefrom, as in the previouslydescribed apparatus.

The guide member 82 is provided with a protruding generally triangular portion 84 extending outwardly toward bale side 9 with the apex thereof initially adjacent to the lower comer of bale side 9 (FIG. 7). The protruding portion 84 is also channeled in the same manner as the remainder of member 82, but has at the apex an anvil or back-up member 85 bridging a portion of channel 84. Back-up member 85 extends generally transversely and parallel to bale side 9, but perpendicular to leg 22, and includes a strap-engaging surface 86 which has been roughened or ridged for better gripping capability. A portion 87 of the lower surface of guide 82 is inclined at an angle to the vertical toward bale l2, and upon surface portion 87 is secured a pneumatic cylinder 88 having a plunger rod 89 and lying along a line intersecting channel 83 and back-up portion 85. Plunger 89 is propelled through a passageway provided in member 82 along this line by cylinder 88, when actuated, to a position wherein the end 93 of the plunger 89 is immediately adjacent surface 86 of back-up member 85. When unactivated, the cylinder 88 maintains plunger 89 in a retracted position beneath and clear of guide channel 64; this is the position maintained by the plunger during the strap feeding operation of the device 40', so that the shifting apparatus does not interfere with the action of the strap guide channels in forming a strap loop 58 about the bale and spaced therefrom. However, as in the case of the previous example, back-up member 85 is maintained in position adjacent the bale during the strap feeding operation, and as the strap is tensioned and leaves the guide channels to engage the bale l2 and form loop 59, it also engages surface 86 of back-up 85 adjacent the lower corner of bale side 9. As in the previous example, an auxiliary roller 68' also extends from auxiliary guide member 52' at the lower corner of bale side 8 to aid in the subsequent shifting of the strap, andthe strap is also passed over in engagement with the roller during the tensioning operation and the strap shifting operation as well.

Upon completion of the tensioning of the strap and its joining with a sea] by the device 40', which then releases the strap into engagement with side 8 to form loop 90' (FIG. 8), the shifting apparatus is put into operation. Cylinder 88 is actuated to drive plunger 89 toward its anvil-adjacent position to capture a portion of the strap loop 90 between its end 93 and the backup surface 86 with a strong applied pressure. With a portion of the strap thus firmly gripped, the entire shifting apparatus is moved upwardly along leg 22' by a drive means 95, which in this case is a pneumatic cylinder secured by bolt 95a at its head end to leg 22 so as to lie vertically therealong. Cylinder 95 has a plugner rod 96 extending vertically downward and which at the end opposite its cylinder is pivotally secured to member 82 at its lowermost portion 98 adjacent to leg 22. Plunger 96 is retracted by cylinder 95 to move the shifting ap paratus upwardly and drive the strap loop 90' together with its seal 67 clockwise until shifting apparatus 80 has moved far enough so that back-up portion is positioned adjacent upper platen 13 and the upper corner of bale side 9; see FIG. 8. When this point has been reached, cylinder 95 driving the carriage 81 stops, and plunger 89 is retracted by cylinder 88 to prepare the shifting apparatus for disengagement from the strap. The shifting apparatus is then returned to its original position with back-up portion 85 adjacent the lower corner of bale 'side 9, either before or after such disengagement, and prior to the feeding of the next strap loop.

Other means of driving the plunger 89 may also be used, for example an electromagnet, or spring and lever combination. Similarly, carriage 81 may be driven by other means, such as an electric motor or ratchet, in one continuous movement or in steps. In the latter case, after each upward step, the plunger 89 is retracted to release strap loop from engagement with its end 93. The cylinder then is again activated to again drive plunger 89 and end 93 into engagement with the strap, whereupon another upward step is executed by the carriage driving means. The construction of the carriage is not confined to that just described; instead, for example, it may comprise a top and a bottom half, each pivoted at their ends which define the midpoint of the carriage upon leg 22. Cylinder would in this case be mounted with its opposite ends pivotally attached to opposite ends of the carriage assembly, so that when actuated, at least the lower carriage half would pivot upwardly bale side 9, thus raising the plunger and anvil together with the engaged strap portion, at least in stepwise fashion as described above.

In any of the embodiments just described, disengagement of the shifting apparatus and its preparation for operation with another strap is carried out simply by moving the leg 22 or 22' transversely along the side of the bale outwardly from the plane of the paper; this is accomplished by movement of frame 20 along

tracks

23 and 24 to a new strapping position in the case of FIG. 1, and by a similar frame (not shown), of which leg 22 is a part, in the case of FIGS. 7 and 8. Since both the

anvils

85 and 34 extend transversely in the direction outwardly from the plane of the paper, the transversely-outward movement of the leg readily disengages them from the completed and shifted strap and positions them, together with the remainder of the shifting apparatus and its auxiliary guides, in alignment with one of the ends of a pair of opposed upper and lower platen channels with another strapping station. At the same time strapping device 40 or 40', together with its auxiliary guides is brought into alignment with the other end of such opposed upper and lower platen channels. In this manner a complete guideway around the bale is again formed at yet another strapping station for another strap loop at a transversely spaced, parallel position along the bale l2, and the just-described strapping and shifting operation repeated, until a plurality of strap loops confine the bale. The strapping locations thereby sequentially selected may be in serial order along the bale sides, or alternating order, or in any order which may be convenient. The total number of strap loops per bale is a function of such factors as bale size and the degree of bale compression desired, and the strap strength.

The packaging of the bale is completed by returning the lower platen to its intake position to release the bale, and the strapping and shifting device returned to a position transversely into the plane of the drawing to await compression of a new bale. The release of the bale causes the bale to expand slightly and take up any slack in its confining strap loops. The stress on the seal is much reduced as compared to a position on a vertical side of the bale, such as side 8. Also, the bale tends to bulge around the strap to somewhat greater degree on the ends (see FIG. 3), since it is at the ends that the platens exerted their compressive force. This is a further aid in protecting the joint from abrasion and sharp objects which might weaken or snag it.

What is claimed is:

l. Strap shifting apparatus for use with bale strapping apparatus comprising: support means; a back-up member carried by said support means and positionable adjacent a bale, said back-up member having a surface adapted to engage a strap positioned around the bale and retained in a loop by a seal at one side of the bale; a pressure applying member; means mounting said pressure-applying member upon said support means for movement between (I) a clearance position enabling said strap to be positioned around said bale and (2) a strap-compressing position adjacent said surface of the back-up member; and means for applying a motive force to said pressure-applying member when said pressure-applying member is in said strap-compressing position for shifting said sea] from said one side of the bale to an end thereof.

2. Strap shifting apparatus as in claim 1 in which said pressure-applying member includes a rotatable wheel which in the strap-compressing position is brought adjacent said back-up member so that said strap engaging surface of said backup member is tangent to a point on the periphery of said wheel, and a portion of said strap is engaged therebetween, and in which said means for applying a motive force rotates said wheel to move said strap between said wheel and surface to thereby shift said strap seal.

3. Strap shifting apparatus as in claim 2 in which said pressure-applying member further includes an elongated arm extending from said support means, said arm carrying said including means for pivoting said arm on said support means at a point adjacent the other arm end, a said arm and wheel being movable between said clearance position in which said arm and wheel are held adjacent said support means and a strap compressing position in which said arm extends inwardly from said support means toward said bale and said wheel is in said backup surface engaging position.

4. Strap shifting apparatus as in claim 3 which further includes a fluid-operated cylinder for moving said arm pivotally between said clearance and said strapcompressing position.

5. Strap shifting apparatus as in claim 2 in which said means for applying a motive force includes a fluid motor coupled to said wheel for rotating said wheel.

6. Strap shifting apparatus as in claim 1 which further 5 includes a carriage engaging said support means and movable thereon adjacent a strap carrying side of the bale in a direction generally parallel to the strap on said side, and in which said pressure-applying member includes a plunger having a gripping surface at one end movable between said clearance and said strapcompressing positions and in which said plunger is reciprocated between said clearance position in which said gripping surface and plunger are held adjacent said support means, and said strap-compressing position in which said plunger is extended toward said back-up member and said gripping surface is positioned adjacent said strap engaging surface of said back-up member to engage a portion of said strap therebetween.

7. Strap shifting apparatus as in claim 6 in which said mounting means includes a cylinder secured to said carriage, and in which said means for applying motive force drives said carriage along said support in said strap direction to move said cylinder and plunger and thereby shift said strap and seal.

8. Strap shifting apparatus as in claim 1 in which said back-up member includes a first portion extending transversely along a side of said bale and having said strap engaging surface facing away from said bale, and a second portion extending generally horizontally from said support means to said first portion.

9. Strap shifting apparatus as in claim 8 in which said first portion is adjustably pivoted upon said second portion to adjust the distance of said first portion from said bale.

10. Strap shifting apparatus as in claim 1 which further includes a pair of strap guide members respectively secured to said support means above and below said pressure-applying member, said guide member defining a portion of a strap path around said bale, said pressure-applying member being located outwardly of said path with respect to the bale when in said clearance position.

11. Strap shifting apparatus as in claim 1 which further includes a pair of strap guide members respectively secured to said means mounting said pressureapplying member, said guide members defining a portion of a strap path around said bale, said pressureapplying member being located outwardly of said path with respect to the bale when in said clearance position.

12. Strap shifting apparatus as in claim 1 in which said back-up member surface is of an arcuate configuration.

13. Strap shifting apparatus as in claim 12 in which said arcuate back-up surface is generally convex facing away from said bale.

14. Strap shifting apparatus as in claim 1, in which said motive force means cooperates with said pressureapplying member and said back-up member for shifting said seal to the lowermost end of the bale.

15. Strap shifting apparatus as in claim 1 which further includes means for driving said pressure-applying member between said clearance position and said strap-compressing position.

16. For use with a bale held compressed along an axis at a packaging station and adapted to have a plurality of generally parallel circumferential straps extended therearound and spaced from each other along an axis generally perpendicular to said compression axis, the straps on at least one side of said bale being accessible at the packaging station, with each such strap passing over bale sides in both the direction of the compression axis and transverse to the compression axis, such strap having a joint at a first point on said bale lying in the direction of said compression axis, apparatus for shifting said joint to a second point on said bale where said joint is transverse to the compression axis comprising: a support member positioned on said one bale side allowing strap access; an anvil member adapted to be sequentially associated with each strap, said anvil member being secured to said support member and extended toward said one bale side, said anvil member having a portion adapted to be positioned adjacent said bale for receiving thereover a portion of a strap feed around said bale whereby said anvil portion is positioned between said one bale side and said strap portion; a gripping device including a rotatable wheel; means mounting said gripping device upon said support for movement between a clearance position away from said bale to enable a strap to be positioned around said bale, and a strap engaging position adjacent said anvil portion wherein said strap portion is held between said wheel and said anvil portion; drive means for moving said gripping device from said clearance position to said strap engaging position; and means for rotating said wheel when said gripping device is in said strapengaging position to move said strap relative to said anvil to thereby shift said sea] from the side of the bale to said second point transverse to said compression axis.

17. Joint shifting apparatus as in claim 16 in which said gripping device further includes an arm pivotally mounted on said support means and carrying said wheel at one end thereof.

18. Joint shifting apparatus as in claim 17 in which said drive means pivotally moves the arm and wheel between said clearance position and said strap-engaging position.

19. Joint shifting apparatus as in claim 18 in which said drive means includes a fluid-operated cylinder mounted with one end secured to said support member and the other end secured to the end of said arm opposite said wheel.

20. Joint shifting apparatus as in claim 17 in which said means for rotating said wheel includes a fluid motor coupled to said wheel and carried by said arm.

21. For use with a bale held compressed along an axis at a packaging station and adapted to have a plurality of generally parallel circumferential straps extend therearound and spaced from each other along an axis generally perpendicular to said compression axis, the straps on at least one side of said bale being accessible at the packaging station, with each such strap passing over bale sides in both the direction of the compression axis and transverse to the compression axis, such strap having a joint at a first point on said bale lying in the direction of said compression axis, apparatus for shifting said joint to a second point on said bale where said joint is transverse to the compression axis comprising; a support member positioned on said one bale side allowing strap access; a carriage mounted on said support member on the side thereof adjacent said bale for movement in a direction generally parallel to said one bale side; an anvil member secured to said carriage and adapted to be sequentially associated with each of said straps, said anvil extending toward said one bale side and having a portion adapted to be positioned adjacent said bale for receiving thereover a portion of a strap being fed around said bale, whereby said anvil portion is positioned between said one bale side and said strap portion; a gripping device mounted on said carrier and movable between a clearance position away from said bale enabling said strap to be positioned around said bale and into engagement with said strap portion tO compress the strap portion against said anvil portion; and drive means for moving said gripping device between said strap clearance and strap engagement positions and means for shifting said carriage relative to said support member when said gripping device is in the strap engagement position to thereby move said strap until said joint is re-positioned to said second point transverse to the compression axis.

22. Joint shifting apparatus as in claim 21 in which said drive means comprises a fluid motor mounted on said carrier, said fluid motor including a ram, said ram including said gripping device at an end thereof.

23. Joint shifting apparatus as in claim 22 in which said fluid motor and ram is defined by a fluid operated cylinder having a driven plunger.

24. Joint shifting apparatus as in claim 21 in which said shifting means includes a fluid motor having one end connected to said support member and the opposite end connected to said carriage.

25. Joint shifting apparatus as in claim 24 in which said fluid motor is arranged with said support and said carriage for moving said joint from said first position to said second position in a continuous stroke.

26. Joint shifting apparatus as in claim 21, in which said anvil is adapted to be sequentially and serially associated with said straps.

27. Apparatus for packaging a bale under compression for use with a press having opposed platens for compressing material into said bale at a packaging station, said press allowing access to two opposed sides of the compressed bale at its corresponding adjacent sides, said platens each having similarly spaced parallel transverse guide channels facing an end of said bale and extending from one of said access sides to the other, said apparatus comprising: an inverted U-shaped frame member having a cross member reaching across said press and a pair of parallel elongated legs extending from said cross member adjacent to and across said sides of said press; strapping means mounted on one of said legs adjacent one of said bale sides for initially feeding a strap length along a planar path disposed circumferentially around said bale which includes one of said guide channels on each platen, then subsequently tensioning the strap to urge it into tight engagement with at least the other of said accessible bale sides and so that the ends of said strap overlap at said one bale side and for crimping a seal around said overlapping ends of said bale-engaged strap; and strap shifting means including a back-up member carried by the other of said legs and positionable adjacent a bale in the plane of said path, said back-up member having a surface adapted to be engaged by a strap fed around the bale by said strapping means, a pressure-applying member, means mounting said pressure-applying member upon said other leg for movement between (1) a clearance position outwardly of said strap path enabling said strap to be fed around said bale by said strapping means and (2) a strap compressing position adjacent said surface of the back-up member, and means for applying a motive force to said pressureapplying member when said pressure-applying member is in said strap-compressing position for shifting said seal from said one side of the bale to an end thereof.

28. Bale packaging apparatus as in claim 27 which further includes a pair of sets of opposed guide members each carried on a respective one of said legs on either side of said packaging station and spaced from the bale, the members of each set having channels aligned with each other and opening toward said bale, one of said sets being associated with said strapping means, and the other of said sets being associated with said shifting means, each of said sets having an upper and lower member respectively adjacent said upper and lower platen when said platens are in the compression position, the guide channels of said upper and lower members each communicating with one of the guide channels of each platen to thereby form an effectively continuous guideway path about a periphery of the bale.

29. A bale packaging apparatus as in claim 28 in which said pressure-applying member in said clearance position is located on the side of one of said guide channels opposite that opening towards said bale.

30. A bale packaging apparatus as in claim 27 in which said strap shifting means shifts said seal from said one side of bale to the bottom end thereof.

31. A bale packaging apparatus as in claim 27 in which a roller device is carried by said leg mounting said strapping means adjacent the lower corner of said bale, said strap engaging said roller device upon tensioning by said strapping means, said roller device aiding the passage of said seal about the lower corner to said bottom end by said shifting means.

32. The method of strapping a bale or the like comprising: providing a supply of compressible material at a strapping station, compacting the compressible material to form a bale, feeding a length of strap around the bale to form a loop including overlapping strap portions, constricting the strap loop into tight binding engagement with at least one side of the bale, forming a closure in the overlapping strap portions at one side of the bale subsequent to the loop constricting step, thereafter moving the closure from said one side of the bale to an end thereof, and maintaining the closure in spaced relation with the corner of said bale between said one side and said end during said movement, and terminating the compacting of the compressible material.

33. The method of claim 32 wherein said closure moving step is performed by moving the closure from said one side of the bale to the bottom thereof.

34. The method of claim 33 wherein said closure moving step is performed by gripping the strap at the side of the bale opposite from said one side, and applying an upward force to the strap.

35. The method of claim 34 wherein the step of applying said upward force to the strap is peformed by compressing the strap between a gripping member and a back-up member, and lifting both of said members.

36. Apparatus for use with bale strapping apparatus for shifting a sealed strap comprising: support means; a gripper assembly carried by said support means including a back-up member and a gripper; means mounting said gripper on said support means for movement into and out of gripping engagement with a strap positioned around a bale and over said back-up member and seal, and means for moving said gripper for shifting said seal from one face of the bale to another.

37. The method of strapping a bale, or the like, comprising: providing a supply of compressible material at a strapping station, compacting the compressible material to form a bale, feeding a length of strap around a bale to form a loop including overlapping strap portions, constricting a strapped loop into tight binding engagement with at least one side of the bale and spacing the strapped loop from at east one side of the bale, forming a closure in the overlapping strap portions at one side of the bale subsequent to the loop constricting step, thereafter moving the closure from said one side of the bale to another side thereof, and maintaining the closure in spaced relation with the corner of said bale between said one side and said end during said movement, and terminating the compacting of the compressible material.

38. The method of strapping a bale or the like comprising: providing a supply of compressible material at a strapping station, compacting the compressible material to form a bale, feeding a length of strap around the bale to form a loop including overlapping strap portions, constricting the strap loop into tight binding engagement with at least one side of the bale, forming a closure in the overlapping strap portions at one side of the bale subsequent to the loop constricting step, and then moving the closure from said one side of the bale to the bottom thereof by gripping the strap at the side of the bale opposite from said one side between a wheel and a back-up member, and applying an upward force to the strap by rotating the wheel to move the strap relative to the back-up member.

39. The method of claim 38 wherein said wheel is moved from an initial clearance position during the feeding, constriction and closure forming steps to a strap engaging position adjacent said back-up member prior to said wheel rotating step.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,834, 297 Dated September 10, 1974 Inventor(s) Gale Huson It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

IN THE SPECIFICATION Column 3, line 49 "operation" should be separation Column 4,

lines

38 and 39, "guidewy" should be guideway Column 4 line 46, "ray" should be may Column 6, line 64, "34g" should be 34a Column 7, 'line 51, "is" should be its Column 7, line 60, "to" should be of Column 9, line 46, "64" should be 64' Column 10, line 7, "plugner" should be plunger Column 10, line 43, toward should be inserted before the word "bale".

Column 10, line 63, associated shouldbe inserted before the word "with" FORM PO-IOSO (10-69) 3,834,297 September 10, 1974 Patent No Dated lnventor(s) Gale Huson PAGE 2 Column ll, Claim 3, line 56, insert rotatable wheel at one end thereof, and said mounting means before the words "including means" Column ll, claim 3, line 58, delete the word "a" Column 13, claim 16, line 17, change "feed" to read fed Column 14, claim 21, line 11, change "t0" to read to Column 15, claim 28, line 12, insert the word guide before the word "channels.

Signed and sealed this 24th day ef December 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. C MARSHALL DANN Attesting Officer Commissioner of Patents

Claims

1. Strap shifting apparatus for use with bale strapping apparatus comprising: support means; a back-up member carried by said support means and positionable adjacent a bale, said back-up member having a surface adapted to engage a strap positioned around the bale and retained in a loop by a seal at one side of the bale; a pressure applying member; means mounting said pressure-applying member upon said support means for movement between (1) a clearance position enabling said strap to be positioned around said bale and (2) a strap-compressing position adjacent said surface of the back-up member; and means for applying a motive force to said pressure-applying member when said pressure-applying member is in said strap-compressing position for shifting said seal from said one side of the bale to an end thereof.

4. Strap shifting apparatus as in claim 3 which further includes a fluid-operated cyliNder for moving said arm pivotally between said clearance and said strap-compressing position.

6. Strap shifting apparatus as in claim 1 which further includes a carriage engaging said support means and movable thereon adjacent a strap carrying side of the bale in a direction generally parallel to the strap on said side, and in which said pressure-applying member includes a plunger having a gripping surface at one end movable between said clearance and said strap-compressing positions and in which said plunger is reciprocated between said clearance position in which said gripping surface and plunger are held adjacent said support means, and said strap-compressing position in which said plunger is extended toward said back-up member and said gripping surface is positioned adjacent said strap engaging surface of said back-up member to engage a portion of said strap therebetween.

11. Strap shifting apparatus as in claim 1 which further includes a pair of strap guide members respectively secured to said means mounting said pressure-applying member, said guide members defining a portion of a strap path around said bale, said pressure-applying member being located outwardly of said path with respect to the bale when in said clearance position.

14. Strap shifting apparatus as in claim 1, in which said motive force means cooperates with said pressure-applying member and said back-up member for shifting said seal to the lowermost end of the bale.

16. For use with a bale held compressed along an axis at a packaging station and adapted to have a plurality of generally parallel circumferential straps extended therearound and spaced from each other along an axis generally perpendicular to said compression axis, the straps on at least one side of said bale being accessible at the packaging station, with each such strap passing over bale sides in both the direction of the compression axis and transverse to the compression axis, such strap having a joint at a first point on said bale lying in the direction of said compression axis, apparatus for shifting said joint to a second point on said bale where said joint is transverse to the compression axis comprising: a support member positioned on said one bale side allowing strap access; aN anvil member adapted to be sequentially associated with each strap, said anvil member being secured tO said support member and extended toward said one bale side, said anvil member having a portion adapted to be positioned adjacent said bale for receiving thereover a portion of a strap feed around said bale whereby said anvil portion is positioned between said one bale side and said strap portion; a gripping device including a rotatable wheel; means mounting said gripping device upon said support for movement between a clearance position away from said bale to enable a strap to be positioned around said bale, and a strap engaging position adjacent said anvil portion wherein said strap portion is held between said wheel and said anvil portion; drive means for moving said gripping device from said clearance position to said strap engaging position; and means for rotating said wheel when said gripping device is in said strap-engaging position to move said strap relative to said anvil to thereby shift said seal from the side of the bale to said second point transverse to said compression axis.

27. Apparatus for packaging a bale under compression for use with a press having opposed platens for compressing material into said bale at a packaging station, said press allowing access to two opposed sides of the compressed bale at its corresponding adjacent sides, said platens each having similarly spaced parallel transverse guide channels facing an end of said bale and extending from one of said access sides to the other, said apparatus comprising: an inverted U-shaped frame member having a cross member reaching across said press and a pair of parallel elongated legs extending from said cross member adjacent to and across said sides of said press; strapping means mounted on one of said legs adjacent one of said bale sides for initially feeding a strap length along a planar path disposed circumferentially around said bale which includes one of said guide channels on each platen, then subsequently tensioning the strap to urge it into tight engagement with at least the other of said accessible bale sides and so that the ends of said strap overlap at said one bale side and for crimping a seal around said overlapping ends of said bale-engaged strap; and strap shifting means including a back-up member carried by the other of said legs and positionable adjacent a bale in the plane of said path, said back-up member having a surface adapted to be engaged by a strap fed around the bale by said strapping means, a pressure-applying member, means mounting said pressure-applying member upon said other leg for movement between (1) a clearance position outwardly of said strap path enabling said strap to be fed around said bale by said strapping means and (2) a strap compressing position adjacent said surface of the back-up member, and means for applying a motive force to said pressure-applying member when said pressure-applying member is in said strap-compressing position for shifting said seal from said one side of the bale to an end thereof.