AU621687B2 - Method and apparatus for applying "l" clips of adhesive tape to shipping containers - Google Patents

Description

:a- 621687 S F Ref: 113155 FORM COMMONWEALTH OF AUSTRALIA PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE: Class Int Class 0b P 0' 4 t Complete Specification Lodged: Accepted: Published: S Priority <Priority: 0 Related Art: Name and Address of Applicant: 0* 040 Minnesota Mining and Manufacturing Company 3M Center Saint Paul Minnesota 55144-1000 UNITED STATES OF AMERICA Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia Address for Service: Complete Specification for the invention entitled: Method and Apparatus for Applying Clips of Adhesive Tape to Shipping Containers The following statement is a full description of this invention, best method of performing it known to me/us including the 5845/5 i i 1 t 4)^i^ aj.i 1 1 Abstract An automatic tape applicator for the application of both front and rear "L"clips of adhesive tape to a container which includes a pivotable applicator arm for initiating the application of adhesive tape to a container moving relative to the applicator, a cutting blade for cutting the tape into clip segments, an arm actuator for pivoting the applicator arm between an application position and a cutting position, and a tensioning actuator for breaking the withdrawal of tape through the applicator when the application arm is pivoted to the cutting position so as to increase the tension of the tape over the cutting blade.

The applicator includes position sensors for sensing the °o position of the container and actuating the arm actuator and the tension actuator at the appropriate times.

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METHOD AND APPARATUS FOR APPLYING CLIPS OF ADHESIVE TAPE TO SHIPPING CONTAINERS Field of the Invention Broadly, the invention relates to the automated taping of containers. Specifically, the invention relates to the automated application of front and rear clips of pressure sensitive adhesive tape to shipping containers, such as display shipping cases, wherein the tape is applied under minimal tension and cut into clip segments by a cutting blade.

Background of the Invention Shipping containers, such as the increasingly popular display shipping case, are commonly sealed by oS0 applying clips of pressure sensitive adhesive tape over o0oo the unsecured edges of the container. Various devices for o. oo applying clips to shipping containers have been 20 developed i.ncluding hand-held automatic and semi-automatic 0 00 .s 0 applicators. The term hand-held applicators is intended to 0000 0000 refer to those applicators small enough to be retained within a hand for assisting in the manual application of tape. The term automatic applicators is intended to refer to those applicators operable in conjunction with a conveyor So for automatically applying clips to a container as the o 00 container is conveyed past the applicator. The term semiautomatic applicators is intended to refer to those nonhand-held applicators which require manipulation of the t container, other than merely conveying the container past the applicator, in order to apply clips to the container.

o 0 o".o Typical automatic clip applicators include an applicator arm pivotably retractable in the direction of conveyor belt motion for initiating the application of tape to a container being conveyed past the applicator arm, a blade for cutting the adhesive tape into clip segments, a buffer assembly for pressing the clip segments into 2 adhesive contact with the container, and a control mechanism for regulating the application and cutting of the tape.

An exemplary automatic clip applicator is shown and described in U.S. Patent Number 4,64-0,731 issued to Learner et al. The applicator of Learner et al includes separately pivotable applicator arms for independently initiating the application of front and rear clips, a lever mounted cutting blade in communication with each applicator arm for strike cutting the tape into clip segments, and rollers for pressing the clip segments into adhesive contact with the container. The applicator employs a push-finger/catch-lever combination to regulate cutting of the tape.

Typical automatic clip applicators employ an applicator arm or other similar mechanism to initiate the Oo oa application of tape, and then rely upon movement of the o, container relative to the applicator to pull adhesive tape 0 through the applicator. Use of container movement to pull the tape through the applicator requires that the initial tape to container bond created by the applicator arm be greater than the tension on the tape being supplied. Tape which is supplied under excessive tension causes the tape to be pulled away from the container before the tape can be cut 0. into an clip segment and roller pressed into place.

The initial tape to container bond created by typical applicator arms is generally a low strength bond due to both the short length of tape actually placed in adhesive contact with the container and the low pressure at tO which the applicator arm is capable of applying the tape.

S 8 Accordingly, clip applicators typically employ a means for reducing the tension at which the tape is supplied so that the tension at which the tape is supplied is less than the tape to container bond strength. "Tension-decreasing" devices commonly employed with automatic clip applicators are generically known as a prestripper I i^ 4 l ^u

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assemblies and operate to reduce the tension at which the tape is supplied by assisting in the removal of tape from the tape roll.

One drawback associated with supplying the adhesive tape in "L" clip applicators at such a low tension is that when the tape is presented to a cutting blade for cutting, the tape tends to slip over the cutting blade so as to cause sloppy and occasionally missed cuts.

Accordingly, a substantial need exists for an clip applicator which can supply tape under decreased tension while providing consistently clean cutting of the tape.

This invention in one broad form provides an adhesive tape applicator, comprising: a means for sequentially automatically applying, at a decreased withdrawal tension, a first length of pressure sensitive adhesive tape transversely across a leading edge of an item moving relative to the applicator whereby continued movement of the item relative to the applicator after application of the first length of tape St t withdraws additional tape from a source of the tape to form a first tape clip, and a second length of pressure sensitive adhesive tape transversely across a trailing edge of the item moving relative to the applicator whereby continued movement of the item relative to the applicator after application of the second length of tape withdraws additional tape from the source of the tape to form a second tape clip; a means for sequentially automatically cutting the tape after ',t a predetermined length of the tape has been withdrawn from the tape source to form the first tape clip, and a predetermined length of the Stape has been withdrawn from the tape source to form the second tape clip; a means for increasing the withdrawal tension of the tape only while the tape is being cut by the cutting means to form the first and second tape clips; and wherein the first and second tape clips are applied over thei leading and trailing edges of the Item in a single continuous motion of the applicator relative to the item.

This invention in a further broad form provides an adhesive tape applicator for the automatic application of clips of a pressure sensitive adhesive tape over two diametrically opposed container edges in a single continuous motion of the applicator relative to the container comprising: ii A/8 A/4VS RLF/1538h S'NT T L j I i: l;jy -4a means for automatically and sequentially applying the distal i end of a length of tape transversely over the leading and trailing edges of a container moving relative to the applicator whereby continued movement of the container relative to the applicator after application of the distal end of the tape to the container withdraws tape from a source of the tape under decreased tension; the application means including (i) a mount for rotatably retaining a roll of adhesive tape, (ii) a retractable applicator arm which can bring the tacky surface of the tape into contact with the container, (iii) an arm actuator for pivoting the applicator arm between an application and a cutting position, and (iv) a guide mechanism for guiding the tape from the mount to the applicator arm; a blade for cutting the adhesive tape after the appropriate length of the tape has been withdrawn from the tape source by the moving container; a tension actuator for increasing the tension of the tape over the blade only when the applicator arm is in the cutting position by preventing additional tape from being withdrawn from the tape source; a control system in communication with the arm actuator and tension actuator for controlling the pivotal position of the applicator I 20 arm and tensioning of the tape; and a position sensing system in communication with the control system for sensing the position of the container and instructing the control system to actuate the arm actuator and tension actuator at the °appropriate times.

j 25 Brief Description of the Drawings Figure 1 is a perspective view of a preferred embodiment of the invention shown in combination with a conveying system.

Figure 2 is an open side view of the invention as depicted in I Oo;o 'Figure 1 30 Figures 3a through 3e schematically demonstrate operation of the invertion as depicted in Figures 1 and 2.

Cp /F/1538h T 0 Figure 4 is an electrical and pneumatic schematic of the invention as depicted in Figures 1 and 2.

Figure 5 is a perspective view of a container sealed by front and rear clips.

Detailed Description of the Invention Including a Best Mode Tape applicator 10 applies both front 101 and rear 102 clips of adhesive tape to a container 200 from a source of adhesive tape 100' as the container 200 moves relative to the applicator Applicator 10 is employed in conjunction with a conveyor system 300 and may be mounted underneath, alongside or above the conveyor belt 310. When mounted underneath, "L" clips are applied to the lower front 201 and lower rear 202 1J5,r edges of the container 200. When mounted alongside, "L" clips are applied to the side front 203 or 205 and corresponding side rear 204 or 206 edges of the container 200. When mounted above, clips are applied to the upper front 207 and upper rear 208 edges of the container 200.

Typically, as with display shipping cases, lower edges 201 and 202 are the edges which require sealing and applicator should be configured underneath the conveyor belt 310 to so as to allow applicator 10 to move relative to a stationary container 200 and apply clips to any pair of diametrically opposed edges such as lower front 201 and upper front 207 or lower side 209 and corresponding upper side 211, etc.

A roll 100' of pressure sensitive adhesive tape a '3 Q 100 is rotatably retained upon mounting arm 20 for use by applicator 10. A plurality of either stationary or rotatable t guide rollers 30 guide tape 100 from mounting arm 20 to an applicator arm 40. The number and configuration of guide rollers 30 may be varied so long as they serve their primary function of smoothly guiding tape 100 from tape roll 100' to t 6 applicator arm 40 under minimal tension.

The applicator 10 embodied in Figures 1 and 2 employs five guide rollers 30a-e to guide tape 100 from I Smounting arm 20 to applicator arm 40. Roller guides 30c, 30d and 30e are rotatably mounted and rotated only by movement of the tape 100 over the guide as tape 100 is pulled by container 200.

Roller guide 30b, on the other hand, is actively rotated by means of a prestripper assembly 50, consisting of a motor drive 51 and a belt 52 connecting the motor 51 to roller guide 30b, for the purpose of power assisting in the removal of tape 100 from the tape roll 100' whenever the tension of tape 100 over roller guide 30b is increased over the tension typically present when tape 100 is static and is not being pulled through the applicator 10. Prestripper assembly 50 may be controlled to rotate roller guide only when tape 100 is being pulled through the applicator Prestripper assembly 50, preferably constantly rotates t ,roller guide 30b and relies upon the increased tensioning of tape 100 around roller guide 30b to cause tape 100 to be pulled from tape roll 100' by the rotating roller guide It is also possible to design prestripper assembly 50 to rotate roller guide 30b only when tape 100 is being pulled I 'by container 200. Roller guide 30b is preferably rotated at a rate slightly in excess of the speed of conveyer belt 310 so that tape 100 is never pulled from the tape roll 100' by a container 200 faster than the pre-stripper 50 can assist in the removal of tape 100 from the tape roll 100'. Other methods of assisting in the prestripping of tape 100 from a tape roll 100' are well known in the art and include such mechanisms as a piston mounted prestrip roller which forms a tape loop between two guide rollers and actively pulls tape from the tape roll only when the length of the tape loop and thereby the position of the piston reaches a predefined point, and (ii) a biased dancer roller which

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7- forms a tape loop and communicates with a driven prestrip roller co actively pull tape at a rate dependent upon the length of the tape loop and the position of the dancer roller.

The non-tacky side of tape 100 must be in contact with roller guide 30b so that tape 100 can slip over roller guide 30b when tape 100 is not being pulled through the applicator 10. Contacting roller guide 30b with the tacky side of tape 100 would result in tape 100 being continuously pulled from the tape roll 100' regardless of the need to supply tape for application to a container 200 and thereby create a tangled mass of tape 100 between roller guide and applicator arm o Roller guides 30a and 30c are configured to guide 0 0 0 105 a maximum length of tape 100 into contact with roller guide S 30b and thereby enhance operation of the prestripper S assembly 50. Roller guides 30d and 30e are configured to continue to guide tape 100 from roller guide 30c to applicator arm Applicator arm 40 is pivotably retractable (i.e.

pivotable) in the direction of conveyor belt 310 movement and pivots between an applying position for presenting tape 'n 100 for application to a container 200 and a cutting position for presenting tape 100 for cutting on a cutting blade 71. Applicator arm 40 includes guide rollers 41 mounted upon and pivotable with applicator arm 40 for guiding tape 100 through applicator arm 40 and retainably pivoting tape 100 in conjunction with the pivoting of t applicator arm 40. Applicator arm 40 also includes a roller

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3 head 42 rotatably mounted on the distal end -7 applicator arm 40 for rotatably contacting co 200 and pressing tape 100 into adhesive engagement wi,. container i 200. Other mechanisms for allowing applicato? n 40 to retract are well known and include the linearly retractable f mechanisms disclosed in U. S. Patent No. 4,238,269 issued to i: 1 1 -I 1 8 Deering, Jr.

The number and configuration of guide rollers 41 may be varied so long as they serve their primary function of smoothly guiding tape 100 through applicator arm 40 and retainably pivoting tape 100 in conjunction with the pivoting of applicator arm 40. The applicator arm embodied in Figures 1 and 2 employs three guide rollers 41ac to guide tape 100 through applicator arm 40 and present the tape 100 for application to a container 200.

1 Proximal end 40a of applicator arm 40 is connected to an arm actuator 60 which includes an arm actuator cylinder 61 pivotably mounted to applicator housing 11 at its proximal end 61a by means of a clevis 63 and an arm 0" actuator piston 62 slidably extending from the distal end od- 5 61b of cylinder 61 and connected to the proximal end 40a of G applicator arm 40 by means of a clevis 64.

o 0 Arm actuator 60 is operable to actively pivot S. applicator arm 40 about axis 43 between the application (up) *a and cutting (down) positions. Arm actuator 60 is also operable to permit the independent pivoting of applicator arm 40 such as by movement of container 200 over applicator arm 40 while continuing to bias applicator arm 40 towards o the position applicator arm 40 occupied prior to the independent pivoting.

When arm actuator piston 62 is retracted, the 0 distal end 40b of applicator arm 40 is positioned up into the path of a conveyed container 200 and presents tape 100 for application to the front surface 221 of the container 200 (Figure Movement of container 200 over roller head jOe° 42 causes applicator arm 40 to pivot to an intermediate position for the application of tape 100 to the base 223 of container 200 (Figure 3a). When applicator arm 40 is in this intermediate position, arm actuator piston 62 is pulled into an intermediate extended position, and biases applicator arm 40 back towards the up position (Figure 3c). When arm i; t i

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r ii 1 .7 -9actuator piston 62 is extended, the distal end 40b of applicator arm 40 is positioned down into applicator 10 for presenting tape 100 to cutting blade 71 (Figures 3b and 3d).

Arm actuator 60 may be selected from any of the commonly available actuators including pneumatic, electropneumatic, hydraulic, electrohydraulic and mechanical. For a detailed discussion of the design and operation of actuators, see Perry Chilton; Chemical Engineers Handbook, Ed., pp. 22-92 through 22-94, Downstream from applicator arm 40 is a pivotable cutting blade assembly 70 which includes a cutting blade 71, a blade mount 72, a pivot control mechanism 73, 74 and a pivotable coverplate 75. Cutting blade 71 may be selected afrom any of the commonly employed styles of cutting blades including smooth and serrated blades having either flat or 2 Go arrowhead laterally shaped cutting edges. Cutting blade assembly 70 should be positioned about one to about four centimeters downstream from roller head 42 when applicator °oSo arm 40 is in the cutting position so that excessive tape 100 does not extend past roller head 42 after the cut is made.

The extension of excessive tape 100 past roller head 42 tends to cause tape 100 to curl back upon itself and thereby o interfere with proper application of the tape 100 to a o °a container 200.

Cutting blade 71 may be mounted so as to be completely stationery, pivotable in the direction of e, conveyer belt 310 movement, swing mounted to forcefully strike tape 100, and the like. Preferably, cutting blade assembly 70 is mounted so as to be pivotable to a limited v.o*a* extent in the direction of conveyer belt 310 movement. It is believed that such limited pivoting of cutting blade assembly 70 allows for a cleaner cut of tape 100 because blade 71 is allowed to move in conjunction with tape 100 as tape 100 is tensioned over and cut by the blade 71.

In the preferred embodiment, a pivotable IY a predetermined length of the.tape has been withdrawn from the tape 1^: source to form the first tape clip, and a predetermined length of the coverplate 75 is configured to cover cutting surface 71b of blade 71 except when blade 71 must be exposed for use.

Coverplate 75 is pivotable in the direction of conveyor belt 310 movement about axis 76 and includes an upwardly extending finger 77 which extends into the path of container 200. Movement of container 200 into contact with finger 77 pivots coverplate 75 away from blade 71 so as to expose blade 71 for use. Coverplate 75 includes a biasing spring 78 which biases coverplate 75 towards cutting blade 71 so that coverplate 75 covers blade 71 when a container 200 is not pressing against finger 77.

The pivoting of cutting blade 71 is limited by means of a stationery mounted screw 73 which passes through Q°toI, a slot (not shown) in the proximal end 72a of blade mount 72. The extent to which blade 71 may be pivoted and the initial angle at which blade 71 is presented may be a a" controlled by altering the length of screw 73 projecting 0 04 c from the screw mounting plate 74.

t A tape buffer assembly 80 is configured downstream of blade assembly 70 for pressing the clip segments 101 and 102 of tape 100 cut by blade 71 into adhesive engagement with container 200. The tape buffer assembly 80 shown in Figures 1 through 3 include a first roller arm 81 having a 1 e first roller pad 83 at the distal end 81b thereof and a second rollor arm 82 having a second roller pad 84 at the distal end 82b thereof. Roller arms 81 and 82 are pivotably mounted at their proximal ends 81a, 82a about the same axis and are spring biased towards each other as well as spring biased as a unit to face upstream. Operation of tape S.36 buffer 80 is schematically demonstrated in Figures 3c-e.

Initial contact of a moving container 200 with buffer assembly 80 causes second roller arm 82 to be pushed underneath container 200 and first roller arm 81 to be pushed downstream so as to roll down the front surface 221 of container 200 until it is pushed underneath container i, '1 diametrically opposed edges of an item having a front surface, a base surface and rear surface, comprising the steps of: /13 200. Both roller pads 83 and 84 then press against the base 223 of container 200 until container 20C passes completely over first roller arm 81. After container 200 passes over roller arm 81, first roller arm 81 begins to follow container 200 towards the second roller arm and rolling up the rear surface 222 of container 200. When container 200 passes completely over buffer assembly 80, the assembly returns to its original upstream facing position in preparation for another container 200.

A tape tensioning actuator 90, for preventing the continued withdrawal of tape 100 through the applicator whenever the tape 100 is presented for cutting on blade 71, is configured between applicator head 42 and tape roll 100'.

Tension actuator 90 is actuated to prevent the continued withdrawal of tape 100 through the applicator 10 wherever the applicator arm 40 is pivoted to the downward or cutting position. Actuation of the tension actuator 90 causes the 00 .4 tension on tape 100 to be increased by the continued pulling of tape 100 by container 200. Such increased tensioning aids 2C7 in obtaining a clean cut of tape 100. When a tension actuator 90 is not employed, tape 100 tends to slip over cutting blade 71 resulting in sloppy and occasionally missed cuts.

various mechanisms may be employed to prevent the 2.5continuejd withdrawal of tape 100 through the applicator including specifically, but not exclusively: an air cylinder having a stationary cylinder 91 and an extendable piston 92 for pressing the tape between the piston 92 and a roller guide 30e, a brake system (not shown) for preventing the rotation of a guide roller 30, which contacts the tacky surface of the tape 100, a brake system (not shown) for preventing tape roll 100' from being rotated, etc.

To simplify construction, it is preferred that the arm actuator 60 and the tension actuator 90 be based upon the sarae actuating principle, preferably pneumatic.

i i--i 1 12 Arm actuator 60 and tension actuator 90 are preferably controlled and actuated by means of position sensors 400 which communicate with actuators 60 and through a control system 500. Position sensors 400 sense the position of a container 200 to which clips are to be applied and activates actuators 60 and 90 accordingly. Such position sensors 400 can be selected from any of the commonly available position sensors including mechanical trip fingers, photosensitive eyes, and the like. The position sensors 400 are preferably adjustable to allow applicator 10 to be used on various sizes of containers 200.

The position sensors 400 may be arranged to operate from either the leading 221 or trailing 222 surfaces of a container 200.

In operation, arm actuator piston 62 is initially

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in a retracted position so as to bias the distal end 40b of C, applicator arm 40 in the application position and tension Cc re C actuator piston 92 is initially in a retracted position so I"as to allow the free withdrawal of tape 100 through the tnfo applicator 10 (Figure Movement of container 200 into contact with roller head 42 causes applicator arm 40 to initiate the application of tape 100 to container 200 and pivot to an intermediate position immediately underneath container 200. Movement of applicator arm 40 to the intermediate position causes arm actuator piston 62 to be pulled to an intermediate position (Figure 3a). In this intermediate retracted position, arm actuator 40 serves to bias applicator arm 40 towards the application position and press roller head 42 into contact with the bottom surface 223 of container 200. Tension actuator piston 92 continues CC t to be in the retracted position so as to allow the continued withdrawal of tape 100. When container 200 trips the first position sensor 400a, tension actuator piston 92 is extended to press tape 100 between piston 92 and roller guide 30e to prevent the continued withdrawal of tape 100 through e a g i r s 51 i i ii: EDt z I' 5845/5 m r "11 1

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13 applicator 10 and arm actuator piston 62 is extended so as i to pivot applicator arm 40 to the cutting position and present tape 100 for cutting on cutting blade 71 (Figure 3b). Container 200 trips the 3econd position sensor 400b when the container 200 is nearly completely past the applicator arm 40 and causes tension actuator piston 92 to retract to allow the withdrawal of tape 100 and arm actuator piston 62 to retract so as to pivot applicator arm 40 back to the application position. However, the presence of container 200 causes applicator arm 40 to stop at the intermediate position against the base surface 223 of container 200. In this intermediate position, applicator arm is biased against the base surface 223 of container 200 and applies tape 100 to the base surface 223 (Figure 3c).

When container 200 trips the third position sensor 400c, s o tension actuator piston 92 is again extended to prevent the S°o« continued withdrawal of tape 100 through the applicator 0 and arm actuator piston 62 is extended so as to pivot oS <applicator arm 40 to the cutting position and present tape Moo 9 o2G 1100 for cutting on cutting blade 71 (Figure 3d). After both 00o clips are applied, tension actuator piston 92 is again retracted to allow the withdrawal of tape 100 through applicator 10 and arm actuator piston 62 is retracted so as to pivot applicator arm 40 back to the application position 00 o 025 for applying tape 100 to the front surface 221 of a subsequent container 200 (Figure 3e). The front 101 and rear 102 clips applied to container 200 are pressed into adhesive contact with container 200 by tape buffer assembly o. Applicator 10 can apply a variety of different B° types of tape 100 including film tape, paper tape, filament tape, and the like. The tape 100 must have sufficient structural integrity to be properly presented for application at roller head 42 and sufficient initial tack to remain adhered to containers 200 as the containers 200 pull 1I 4-: l I 14 the tape 100 through the applicator 10. Applicator 10 is particularly well suited to the application of filament tape which, due to its high lateral tear strength, tends to cause the most difficulties when being cut in automatic clip applicators. Tapes which can be usefully employed in applicator 10 includes specifically, but not exclusively: filament tapes such as 3M product code 880, 3M product code 889, 3M product code 898 and 3M product code 8809; and box sealing tapes such as 3M product code 353, 3M product code 355, 3M product code 371, 3M product code 373, 3M product code 375 and 3M product code 3723.

Applicator 10 is particularly well suited to the application of "L"clips 101 and 102 over right angle edges as are typically present on most shipping containers, ,1,5 including display shipping cases. However, applicator 10 is i t I also capable of applying clips 101 and 102 over edges created by an angle slightly greater or less than S degrees. In addition, upon minor modification of applicator arm 40, the applicator 10 can also apply "L"clips 101 and 102 to edges created by an angle substantially greater than or less than 90 degrees.

When applying "L"clips 101 and 102, particularly when the container 200 is light or small, it is preferred to employ some type of a retaining mechanism 350 to ensure that container 200 remains in contact with conveyor belt 310 and can pivot applicator arm t, Applicator 10 can consistently apply clean "L" clips of adhesive tape 100 up to a conveyor belt 310 speed of about 46 m/sec. Speeds in excess of about 46 m/sec. tend Q' to cause the tape 100 to pull away from the base surface 223 S: of container 200 when applying the rear clip and also tend to create timing problems as arm actuator 60 cannot react quickly enough.

4 J j coemplete non- li mi t ing u.der-stand_ing-ef the invention. Since i L~ i i ii I i -r

Claims (11)

1. An adhesive tape applicator, comprising: a means for sequentially automatically applying, at a decreased withdrawal tension, a first length of pressure sensitive adhesive tape transversely across a leading edge of an item moving relative to the applicator whereby continued movement of the item relative to the applicator after application of the first length of tape withdraws additional tape from a source of the tape to form a first tape clip, and a second length of pressure sensitive adhesive tape transversely across a trailing edge of the item moving relative to the applicator whereby continued movement of the item relative to the applicator after application of the second length of tape withdraws additional tape from the source of the tape to form a second tape clip; a means for sequentially automatically cutting the tape after a predetermined length of the tape has been withdrawn from the tape source to form the first tape clip, and a predetermined length of the tape has been withdrawn from the tape source to form the second tape clip; a means for increasing the withdrawal tension of the tape only while the tape is being cut by the cutting means to form the first and second tape clips; and wherein the first and second tape clips are applied over the leading and trailing edges of the item in a single continuous motion of the applicator relative to the item.

2. The applicator of claim 1 wherein the applying means includes a mount for retaining the source of adhesive tape, (ii) an applicator i arm pivotable in the direction of movement of the item for presenting the tacky surface of the tape for contact with the item, and (iii) a guide mechanism for guiding the tape from the mount to the applicator arm.

3. The applicator of claim l wherein the means for increasing the withdrawal tension of the tape is a tension actuator which prevents additional tape from being pulled through the applicator.

4. The applicator of claim 2 wherein the applicator can apply tape td the item when the item Is a display shipping case.

The applicator of claim 1 wherein the cutting means is a blade which can pivot in the direction of tape movement.

6. An adhesive tape applicator for the automatic application of clips of a pressure sensitive adhesive tape over two diametrically opposed container edges in a single continuous motion of the applicator LF/1538h SN T t 2 heaplcaoro cai weri te plyngman icLLs RLF/1538h ICI C 1 16 relative to the container comprising: a means for automatically and sequentially applying the distal end of a length of tape transversely over the leading and trailing edges of a container moving relative to the applicator whereby continued movement of the container relative to the applicator after application of the distal end of the tape to the container withdraws tape from a source of the tape under decreased tension; the application means including (i) a mount for rotatably retaining a roll of adhesive tape, (ii) a retractable applicator arm which can bring the tacky surface of the tape into contact with the container, (iii) an arm actuator for pivoting the applicator arm between an application and a cutting position, and (iv) a guide mechanism for guiding the tape from the mount to the applicator arm; a blade for cutting the adhesive tape after the appropriate length of the tape has been withdrawn from the tape source by the moving container; a tension actuator for increasing the tension of the tape over the blade only when the applicator arm is in the cutting position by preventing additional tape from being withdrawn from the tape source; a control system in communication with the arm actuator and tension actuator for controlling the pivotal position of the applicator arm and tensioning of the tape; and a position sensing system in communication with the control system for sensing the position of the container and instructing the control system to actuate the arm actuator and tension actuator at the appropriate times.

7. A method of applying clips of adhesive tape over two diametrically opposed edges of an item having a front surface, a base surface and rear surface, comprising the steps of: moving the item relative to a retractable applicator arm; contacting the applicator arm and the front surface of the item so as to adhesively apply the distal end of a length of tape to the front surface of the item; allowing the item to continue to move relative to the applicator arm so as to withdraw tape through the arm; retracting the applicator arm so as to cut the tape on a cutting surface and thereby create a front clip tape having a front portion bonded to the front surface of the item and a base portion bondable to the base surface of the item; I t I LF/1538h NT 0 '-tVT F/1538h -r S- 17 increasing the tension of the tape over the cutting surface by I increasing the force necessary to continue the withdrawal of tape; releasing the tape so as to allow the tape to again be withdrawn under decreased tension; contacting the applicator arm and the base surface of the item proximate the rear surface of the item so as to adhesively apply the distal end of the tape to the base surface of the item proximate the rear surface; allowing the item to continue to move relative to the applicator arm so as to withdraw additional tape; retracting the applicator arm so as to cut the tape on a cutting surface and thereby create a rear clip tape having a base portion bonded to the base surface of the item and a rear portion bondable to the rear surface of the item; increasing the tension of the tape over the cutting surface by increasing the force necessary to continue the withdrawal of tape; 4 releasing the tape so as to allow the tape to again be withdrawn under decreased tension; and returning the applicator arm to its original position for contacting the front surface of a subsequent item.

8. The method of claim 7 wherein the applicator arm is retracted by pivoting and pivoted by means of an arm actuator, actuated in response to the position of the item relative to the applicator.

9. The method of claim 7 wherein the item is moved relative to the applicator arm by a conveyor belt.

10. An adhesive tape applicator substantially as described herein with reference to Figures 1 to 4 of the accompanying drawings.

11. A method of applying clips of adhesive tape over two i diametrically opposed edges of an item, said method being substantially j as described herein with reference to the accompanying drawings, DATED this THIRD day of JANUARY 1992 Minnesota W'ning and Manufacturing Company Patent Attorneys for the Applicant SPRUSON FERGUSON :R )F/1538h STI* i 3 I Ai^, ,I