Patent Publication Number: US-7913736-B2

Title: Apparatus and method for affixing adhesive tape

Description:
BACKGROUND OF INVENTION 
     1. Technical Field 
     The present invention relates to apparatuses for affixing an adhesive tape to a workpiece and to a method for affixing an adhesive tape, and specifically, the invention relates to improvements in techniques for affixing adhesive tape to workpieces having a cylindrical portion. 
     2. Background Art 
     Adhesive tapes, such as labels printed with various types of product information or with barcodes, may be automatically affixed to an outer peripheral surface of a cylindrical portion of a workpiece. As methods for affixing such adhesive tapes, for example, see Japanese Unexamined Application Publications Nos. 8-169428 (first patent document) and 2001-225820 (second patent document). 
     In the technique disclosed in the first patent document, an adhesive tape is cut in a predetermined length by a tape-feeding portion, and the cut adhesive tape is fed to a tape-holding mechanism. The cut adhesive tape is affixed to an outer peripheral surface of a bar-shaped workpiece disposed perpendicularly to the adhesive tape on a base in the tape-holding mechanism. In the technique disclosed in the second patent document, an adhesive tape with a predetermined size is held between a thrust roller and a cylindrical container which is vertically held by a container-holding device. Then, the adhesive tape is affixed to an outer peripheral surface of the cylindrical container by rotating the cylindrical container. 
     In the technique of the first patent document, the adhesive tape is affixed to the outer peripheral surface of the workpiece from above in a condition in which an adhesive surface faces downward, whereby the workpiece is difficult to pull out after the adhesive tape is affixed. On the other hand, in the second patent document, the adhesive tape is affixed to the outer peripheral surface of the cylindrical container by rotating the cylindrical container with respect to the adhesive tape. Therefore, it is difficult to produce a free-hanging tag by affixing an adhesive tape that is longer than the length of the outer periphery of the cylindrical container. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an apparatus and a method for affixing an adhesive tape, wherein a workpiece is upwardly pulled out after the adhesive tape is affixed, and the adhesive tape is affixed to the outer peripheral surface of the cylindrical portion of the workpiece to form a free-hanging tag. 
     The present invention provides an apparatus for affixing an adhesive tape having an adhesive to a workpiece having a cylindrical portion and an outer peripheral surface thereof, and the apparatus includes a tape-feeding device for feeding an adhesive tape below the outer peripheral surface in a condition in which the adhesive surface upwardly faces in a direction approximately perpendicular to an axis of the cylindrical portion, a tape-cutting device for cutting the adhesive tape fed from the tape-feeding device in a predetermined length, and a tape-affixing device for thrusting and affixing the adhesive surface of the adhesive tape which was cut by the tape-cutting device to the outer peripheral surface of the cylindrical portion in such a way that the tape-affixing device passes through both sides of the outer peripheral surface of the cylindrical portion from below thereof so as to elevate the adhesive tape. The tape-affixing device is arranged for the cut adhesive tape to be longer than the length of the outer periphery of the cylindrical portion such that adhesive surfaces at the ends of the cut adhesive tape are pressed and are adhered to each other after the adhesive surface of the adhesive tape was thrust and was adhered to the outer peripheral surface of the cylindrical portion. 
     In the apparatus for affixing an adhesive tape of the present invention, an adhesive tape is thrust and affixed to the outer peripheral surface of the cylindrical portion of a workpiece in such a way that the tape-affixing device passes through both sides of the outer peripheral surface of the cylindrical portion from below thereof so as to elevate the adhesive tape in a condition in which an adhesive surface of the cut adhesive tape faces upward. Then, adhesive surfaces at the ends of the cut adhesive tape longer than the length of the outer periphery of the cylindrical portion are pressed and are adhered to each other after the adhesive surface of the adhesive tape was thrust and was adhered to the outer peripheral surface of the cylindrical portion. Therefore, the adhesive tape is affixed to the cylindrical portion of the workpiece so as to form a free-hanging tag, and the workpiece is upwardly pulled out after the adhesive tape is affixed. Moreover, the adhesive tape can be automatically affixed, whereby the time for affixing is decreased, and the workpiece may be handled with both hands. 
     The apparatus for affixing an adhesive tape of the present invention may have various structures. For example, the tape-feeding device may comprise a rotating roll on which an adhesive tape is rolled and a rotating member by which the adhesive tape rolled on the rotating roll is fed in a predetermined direction. 
     In this case, the adhesive tape rolled on the rotating roll is fed in a predetermined direction by the rotation of a first rotating member and a second rotating member, whereby the adhesive tape can be fed below the cylindrical portion of the workpiece with a simple structure. Therefore, the structure of the apparatus can be simply formed. 
     In order to improve the performance of the tape-feeding device, various structures may be used. For example, the rotating member may comprise a first rotating member and a second rotating member which is disposed downstream of the first rotating member in a feeding path for an adhesive tape with a predetermined distance. The second rotating member may have a larger outer diameter than that of the first rotating member, and it may be set to rotate in the same direction and rotating frequency as the first rotating member. 
     In this case, the circumferential speed of the adhesive tape is faster at the second rotating member than at the first rotating member. According to such a difference between the circumferential speed at the first and the second rotating members, a back tension occurs in the adhesive tape between the first and the second rotating members, whereby the adhesive tape is easily peeled off from the second rotating member. Therefore, the adhesive tape can be smoothly fed. 
     The first rotating member may contact with the adhesive tape at a larger angle than the angle at which the second rotating member contacts with the adhesive tape, and the amount of the disposed first rotating member may be larger than that of the disposed second rotating member. In this case, adhesive power with respect to the adhesive tape of the second rotating member is smaller than that of the first rotating member, whereby the adhesive tape is very easily peeled off from the second rotating member. Therefore, the adhesive tape can be further smoothly fed. 
     The feeding path for the adhesive tape may be formed with a flat portion opposing the outer peripheral surface of the first rotating member, a concave portion opposing the outer peripheral surface of the second rotating member, and a connecting portion smoothly connecting the flat portion and the concave portion. In this case, the adhesive tape between the flat portion and the outer peripheral surface of the first rotating portion is fed in a flat shape in cross section, and the adhesive tape between the concave portion and the outer peripheral surface of the second rotating member is fed in a downwardly convex curved shape in cross section. Therefore, the extensibility of the adhesive tape is improved, and buckling strength is improved. Accordingly, the adhesive tape can be more smoothly fed. 
     In order to improve the performance of the tape-cutting device, various structures may be used. For example, the tape-cutting device may comprise a cutter rotatably provided to the shaft and downwardly rotating to the adhesive surface of the adhesive tape so as to cut, and a suction member provided at the shaft so as to synchronously rotate with the cutter. After the adhesive tape is cut, the cutter upwardly rotates and separates from the feeding path for the adhesive tape, and the suction member upwardly rotates and returns to the feeding path for the adhesive tape, so that a reverse surface of the adhesive surface of the adhesive tape cut by the cutter is suctioned and is peeled off from the cutter. In this case, the suction member is near the cutter and can peel off the cut adhesive tape from the cutter without causing damage. 
     In order to improve the performance of the tape-affixing device, various structures may be used. For example, the tape-affixing device may comprise a guide plate having a tape-feeding groove to which an adhesive tape is fed and having a workpiece-disposing groove formed in a direction perpendicular to the tape-feeding groove and on which the cylindrical portion of the workpiece is disposed, a through hole penetrating in a direction perpendicular to the crossing portion of the tape-feeding groove and the workpiece-disposing groove, and a thrust member provided in the through hole and is liftable and thrusting the outer peripheral surface of the cylindrical portion of the workpiece by raising therein. Two claws may be formed on the upper surface portion of the thrust member and may oppose the cylindrical portion of the workpiece in the upstream and the downstream of the feeding path for the adhesive tape with respect to the axis of the cylindrical portion of the workpiece. A hollow portion may be formed under the claws of the thrust member, and the two claws may be elastically deformable according to thrusting power due to the outer peripheral surface of the cylindrical portion of the workpiece. 
     In this case, according to the rise of the thrust member through the through hole penetrating in a direction perpendicular to the crossing portion of the tape-feeding groove and the workpiece-disposing groove, the two claws of the thrust member thrust and affix the adhesive tape on the outer peripheral surface of the cylindrical portion of the workpiece in such a way that the tape-affixing device passes through both sides of the outer peripheral surface of the cylindrical portion from below thereof so as to elevate the adhesive tape while deforming in accordance with the shape in cross section of the cylindrical portion of the workpiece. Simultaneously, ends of the adhesive tape smoothly rise along the tape-feeding groove while the adhesive tape is affixed to the outer peripheral surface of the cylindrical portion of the workpiece. Then, the two claws return to the former shape after they pass over the upper side of the outer peripheral surface of the cylindrical portion of the workpiece, and they continue to rise. Simultaneously, the cylindrical portion of the workpiece relatively moves down with respect to the claws in the hollow portion disposed under the claw, and the two claws hold ends of the adhesive tape longer than the length of the outer peripheral surface of the cylindrical portion of the workpiece and affix both adhesive surfaces thereof each other. 
     In this case, the adhesive tape is disposed at the tape-feeding groove of the guide plate, and the workpiece is disposed at the workpiece-disposing groove of the guide plate, whereby the cylindrical portion of the workpiece can be accurately positioned perpendicular to the adhesive tape. Moreover, the longitudinal length of the tape-feeding groove and the position where the adhesive tape is cut by the tape-cutting portion are suitably designed, whereby the centers of the cylindrical portion of the workpiece and the adhesive tape can be accurately made to coincide. The two claws of the thrust member are raised along the through hole formed in a direction perpendicular to the crossing portion of the tape-feeding groove and the workpiece-disposing groove, and the adhesive tape shifts along the tape-feeding groove when it is affixed by the two claws, whereby the adhesive tape may be affixed without displacement in the longitudinal direction and the width direction. 
     The surfaces of the two claws opposing the cylindrical portion of the workpiece may contact each other at the lower end portion and may have an upwardly convex shape in which the surfaces are gradually separated from each other toward upward direction. In this case, the adhesive tape is thrust by fitting to the outer peripheral surface of the cylindrical portion of the workpiece, whereby the adhesive tape may be affixed thereto while avoiding wrinkles. 
     A method for affixing an adhesive tape of the present invention is used for an apparatus for affixing an adhesive tape of the present invention. That is, in the method for affixing an adhesive tape of the present invention, an adhesive tape is fed below the outer peripheral surface of a cylindrical portion of a workpiece in a condition in which an adhesive surface faces upwardly in a direction approximately perpendicular to the axis of the cylindrical portion. Then, the fed adhesive tape is cut in a predetermined length, and the adhesive surface of the cut adhesive tape is thrust and affixed to the outer peripheral surface of the cylindrical portion of the workpiece in such a way that a tape-affixing device passes through both sides of the outer peripheral surface of the cylindrical portion from below thereof so as to elevate the adhesive tape. Adhesive surfaces at the ends of the cut adhesive tape longer than the length of the outer periphery of the cylindrical portion are pressed and are adhered to each other after the adhesive surface of the adhesive tape was thrust and was adhered to the outer peripheral surface of the cylindrical portion. The method for affixing an adhesive tape of the present invention provides the same functions and effects as the apparatus for affixing an adhesive tape of the present invention. 
     According to the method or the apparatus for affixing an adhesive tape of the present invention, an adhesive surface of a cut adhesive tape is thrust and affixed to the outer peripheral surface of an cylindrical portion of a workpiece in such a way that a tape-affixing device passes through both sides of the outer peripheral surface of the cylindrical portion from below thereof so as to elevate the adhesive tape. Adhesive surfaces at ends of the cut adhesive tape longer than the length of the outer periphery of the cylindrical portion are pressed and are adhered to each other after the adhesive surface of the adhesive tape was thrust and was adhered to the outer peripheral surface of the cylindrical portion. Therefore, the adhesive tape is affixed to the outer peripheral surface of the cylindrical portion of the workpiece in the form of a free-hanging tag, and the workpiece is upwardly pulled out after the adhesive tape is affixed. Moreover, the adhesive tape can be automatically affixed to the workpiece, whereby time for affixing is decreased, and the workpiece may be handled with both hands. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  shows a structure of an apparatus for affixing an adhesive tape relating to an embodiment of the present invention: it is a top view of a structure below a rotating roll of a tape-feeding portion in the apparatus. 
         FIG. 2  shows a front view of the apparatus for affixing an adhesive tape viewed from the direction of arrow  2 A in  FIG. 1 . 
         FIG. 3  shows a side view of the apparatus for affixing an adhesive tape taken in the direction of the arrows along line  3 A- 3 A in  FIG. 1 . 
         FIG. 4  is a top view showing a part of a structure of a tape-feeding portion of an apparatus for affixing an adhesive tape relating to an embodiment of the present invention. 
         FIGS. 5A to 5C  show enlarged structures of a tape-feeding portion of an apparatus for affixing an adhesive tape relating to an embodiment of the present invention, wherein  FIG. 5A  is a front view of the apparatus,  FIG. 5B  is a sectional view taken along line a-a in  FIG. 5A , and  FIG. 5C  is a sectional view taken along line b-b in  FIG. 5A . 
         FIG. 6  is a top view showing an enlarged structure of a tape-cutting portion of an apparatus for affixing an adhesive tape relating to an embodiment of the present invention. 
         FIGS. 7A to 7C  show operating states of the tape-cutting portion of  FIG. 6 , wherein  FIG. 7A  is a side view showing a rising state of an upper cutter of the tape-cutting portion,  FIG. 7B  is a front view showing a rising state of an upper cutter of the tape-cutting portion, and  FIG. 7C  is a side view showing a downward moving state of an upper cutter of the tape-cutting portion. 
         FIG. 8  is a top view showing an enlarged structure of a tape-affixing portion of an apparatus for affixing an adhesive tape relating to an embodiment of the present invention. 
         FIG. 9  is a side view showing a state in which an adhesive tape is being affixed to a workpiece in the tape-affixing portion of  FIG. 8 . 
         FIG. 10  shows a side view of the tape-affixing portion of  FIG. 8 . 
         FIG. 11  shows a component drawing of one side portion of an example of a workpiece on which an adhesive tape is affixed by an apparatus for affixing an adhesive tape relating to an embodiment of the present invention. 
     
    
    
     PREFERRED EMBODIMENTS OF THE INVENTION 
     1 Compositions of Embodiments 
     1-1 Overall Structure of Apparatus 
     An embodiment of the present invention will be explained hereinafter with reference to drawings.  FIGS. 1 to 3  show structures of an apparatus  1  for affixing an adhesive tape relating to an embodiment of the present invention.  FIG. 1  shows a structure of an apparatus  1  for affixing an adhesive tape; it is a top view of a structure below a rotating roll  101  of a tape-feeding portion  20  in the apparatus  1 .  FIG. 2  shows a front view of the apparatus  1  for affixing an adhesive tape viewed from the direction of an arrow  2 A of  FIG. 1 .  FIG. 3  shows a side view of the apparatus  1  for affixing an adhesive tape taken in the direction of the arrows along the line  3 A- 3 A in  FIG. 1 . Double-dashed chain lines, which correspond to a thrust member  122  in  FIG. 2 , show the thrust member  122  after an adhesive tape T is affixed, and a double-dashed chain line, which corresponds to an upper cutter  112 , shows the upper cutter  112  after the adhesive tape T is cut. It should be noted that the method for affixing an adhesive tape of the present invention is performed by the apparatus  1  for affixing an adhesive tape. 
     The apparatus  1  for affixing an adhesive tape is used for affixing the adhesive tape T to a workpiece W having a cylindrical portion. One side of the adhesive tape T is an adhesive surface formed by coating with an adhesive, for example. The apparatus  1  for affixing an adhesive tape comprises a base  10 . The base  10  is provided with a tape-feeding portion  20  (tape-feeding device), a tape-cutting portion  30  (tape-cutting device), and a tape-affixing portion  40  (tape-affixing device), and a tape-feeding path  50  to which the adhesive tape T is fed linearly extending from the tape-feeding portion  20  to the tape-affixing portion  40 . The cylindrical portion of the workpiece W on which the adhesive tape T is affixed is disposed in the tape-affixing portion in a direction perpendicular to the tape-feeding path  50 . 
     The tape-feeding portion  20  feeds the adhesive tape T through the tape-feeding path  50  in a condition such that the adhesive surface faces upwardly so as to feed the adhesive tape T below the cylindrical portion of the workpiece W in a direction perpendicular to the axis of the cylindrical portion of the workpiece W. The tape-cutting portion  30  cuts the adhesive tape T fed by the tape-feeding portion  20  in a predetermined length. The adhesive tape T in which the adhesive surface faces upwardly is thrust and is affixed to the outer peripheral surface of the cylindrical portion of the workpiece W in such a way that a tape-affixing portion  40  passes through both sides of the outer peripheral surface of the cylindrical portion from below thereof so as to elevate the adhesive tape T. Then, the tape-affixing portion  40  thrusts and affixes adhesive surfaces at ends of the adhesive tape T longer than the length of the outer periphery of the cylindrical portion of the workpiece W to each other. The tape-feeding portion  20 , the tape-cutting portion  30 , and the tape-affixing portion  40  will be explained in detail hereinafter. 
     1-2 Composition of Tape-Feeding Portion 
       FIG. 4  is a top view showing a part of a structure of a tape-feeding portion  20 .  FIGS. 5A to 5C  show enlarged structures of the tape-feeding portion  20 , wherein  FIG. 5A  is a front view of the apparatus,  FIG. 5B  is a sectional view taken along line a-a in  FIG. 5A , and  FIG. 5C  is a sectional view taken along line b-b in  FIG. 5A . 
     The tape-feeding portion  20  comprises a rotating roll  101  on which the adhesive tape T is rolled. The adhesive surface of the adhesive tape T faces the radial inner side of the rotating roll  101 . The adhesive tape T rolled on the rotating roll  101  is fed through the tape-feeding path  50  by rotating a small diameter disc  102  (first rotating member) and a large diameter disk  103  (second rotating member). The disk  102  has a rotating shaft  105  and the disk  103  has a rotating shaft  106 , and the rotating shafts  105  and  106  are connected to a rotating mechanism  104  so as to rotate in the same direction and rotating frequency. 
     The small diameter disk  102  is provided upstream of the tape-feeding path  50 , and the large diameter disk  103  is provided downstream of the tape-feeding path  50 . The disks  102  and  103  overlap between the rotating shafts  105  and  106 , and the lower sides of the outer peripheral surfaces thereof are disposed so as to face the tape-feeding path  50 . The outer peripheral surfaces of the disks  102  and  103  are formed with a slip prevention portion with respect to the adhesive tape T. 
     The small diameter disk  102  has a smaller outer diameter than that of the large diameter disk  103 , and the amount of the disposed small diameter disk  102  is larger than that of the disposed large diameter disk  103 . In the embodiment, four small diameter disks  102  are disposed at even intervals, and one large diameter disk  103  is disposed between the two small diameter disks  102  placed at the middle of the four small diameter disks  102 . The small diameter disk  102  contacts the adhesive tape T at larger angle than the angle at which the large diameter disk  103  contacts the adhesive tape T. It should be noted that the angle at which the small diameter disk  102  contacts the adhesive tape T is indicated by an angle Q in  FIG. 5A . 
     In the tape-feeding path  50  in the tape-feeding portion  20 , a flat portion  51  is formed at a portion opposing the lower side of the outer peripheral surface of the small diameter disk  102 , and a concave portion  52  is formed at a portion opposing the lower side of the outer peripheral surface of the large diameter disk  103 . The flat portion  51  and the concave portion  52  are smoothly connected by a connecting portion  53 . The flat portion  51  has a width slightly greater than that of the adhesive tape T, and the upper side of the concave portion  52  has the same width as the flat portion  51 . 
     1-3 Composition of Tape-Cutting Portion 
       FIG. 6  is a top view showing an enlarged structure of a tape-cutting portion  30 .  FIGS. 7A to 7C  show operating states of the tape-cutting portion  30 , wherein  FIG. 7A  is a side view showing a raising state of an upper cutter  112  of the tape-cutting portion  30 ,  FIG. 7B  is a front view showing a raising state of an upper cutter  112  of the tape-cutting portion  30 , and  FIG. 7C  is a side view showing a downward moving state of an upper cutter  112  of the tape-cutting portion  30 . The tape-cutting portion  30  comprises a lower cutter  111  and an upper cutter  112  for cutting the adhesive tape T, and a suction member  114  for applying suction to a reverse surface of the adhesive surface of the adhesive tape T. 
     The lower cutter  111  is fixed on the base  10 . The tape-feeding path  50  for the adhesive tape T extends over the upper surface of the lower cutter  111 . An end portion of the upper cutter  112  is provided to a turning shaft  113  at the side portion of the lower cutter  111 , and the other end portion of the upper cutter  112  is turnable around the turning shaft  113 . The other end portion of the upper cutter  112  is connected with a turning mechanism  115  and is turned thereby. The upper cutter  112  is disposed in a direction perpendicular to the tape-feeding path  50 . The upper cutter  112  turns with respect to the lower cutter  112  from a raising state shown in  FIGS. 7A and 7B  to a downward moving state shown in  FIG. 7C , thereby cutting the adhesive tape T. The turning range of the upper cutter  112  is limited to a range of angle R shown in  FIG. 7C . 
     The suction member  114  is adjacent to the upper cutter  112  and is turnably provided around the turning shaft  113 , and it synchronously slides with the upper cutter  112  by friction occurring at the upper cutter  112 . The turning range of the suction member  114  is limited to a range of angle S shown in  FIG. 7C , and the angle S is smaller than the angle R which is the turning range of the upper cutter  112 . The suction member  114  has a suction opening  114 A connected to a vacuum portion (not shown in the figures). 
     When the suction member  114  is in a raising state, the suction opening  114 A is placed at the tape-feeding path  50  as shown in  FIGS. 7A and 7B , whereby the adhesive tape T can be held by suction. When the suction member  114  is in downward moving state, the suction opening  114 A is separated from the tape-feeding path  50 , whereby the adhesive tape T cannot be held by suction. 
     1-4 Composition of Tape-Affixing Portion 
       FIG. 8  is a top view showing an enlarged structure of a tape-affixing member  40 .  FIG. 9  is a side view showing a state in which an adhesive tape T is being affixed to a workpiece W.  FIG. 10  is a side sectional view showing an enlarged structure of the tape-affixing member  40 . It should be noted that, in  FIG. 9 , double-dashed chain lines corresponding to the adhesive tape T show a state in which the adhesive tape T is being affixed, and solid lines corresponding to a thrust member  122  shows the thrust member  122  after the adhesive tape T is affixed. The tape-affixing portion  40  comprises a guide plate  121  having a rectangular parallelepiped shape. A tape-feeding groove  54  forming a part of the tape-feeding path  50  is formed in the longitudinal direction of the guide plate  121 . A workpiece-disposing groove  121 A on which a workpiece W is disposed is formed in a direction perpendicular to the tape-feeding groove  54  in the width direction of the guide plate  121 . 
     The cylindrical portion of the workpiece W on which the adhesive tape T is affixed is disposed at the crossing portion of the tape-feeding groove  54  and the workpiece-disposing groove  121 A. In the extending direction of the tape-feeding path  50 , a distance from the upper cutter  112  to the axis of the cylindrical portion of the workpiece W and a distance from the axis of the cylindrical portion of the workpiece W to the right end of the tape-feeding groove  54  are defined to have a length l. Therefore, when the adhesive tape T reaches the right end of the tape-feeding groove  54 , the adhesive tape T is cut by the upper cutter  112 , thereby yielding the adhesive tape T having a length of L ( 2   l ) in which the center of the workpiece W corresponds to the center in the longitudinal direction of the adhesive tape T. 
     A through hole  121 B penetrating in a direction perpendicular to the guide plate  121  is formed at the crossing portion of the tape-feeding groove  54  and the workpiece-disposing groove  121 A. A thrust member  122  is provided in the through hole  121 B and is liftable, and it is made from an elastic material, for example. The thrust member  122  is lifted by a lifting mechanism  123  connected to the lower end portion of the thrust member  122 . The adhesive tape T is affixed to the cylindrical portion of the workpiece W by raising the thrust member  122 . 
     Claws  122 A and  122 B are formed on the upper surface of the thrust member  122 , and they thrust the outer peripheral surface of the cylindrical portion of the workpiece W passing through both sides of the outer peripheral surface of the cylindrical portion of the workpiece W from below thereof so as to elevate the adhesive tape. A hollow portion  122 C is formed under the claws  122 A and  122 B. The claw  122 A is disposed downstream of the tape-feeding path  50  with respect to the axis of the cylindrical portion of the workpiece W, and the claw  122 B is disposed upstream of the tape-feeding path  50  with respect to the axis of the cylindrical portion of the workpiece W, and they oppose each other. The sides of the claws  122 A and  122 B opposing the cylindrical portion of the workpiece W contact each other at the lower end portion, and they have an upwardly convex shape in which the surfaces are gradually separated from each other toward upward direction. The claws  122 A and  122 B having such a shape contact with the workpiece W in a range U shown in  FIG. 8 , when the adhesive tape T is affixed to the workpiece W by raising the thrust member  122 . 
     2 Operation of Embodiment 
     An operation of the apparatus  1  for affixing an adhesive tape will be explained with reference to the drawings. As shown in  FIG. 4  and  FIGS. 5A to 5C , in the tape-feeding portion  20 , when the small diameter disk  102  and the large diameter disk  103  are driven and rotate by the rotating mechanism  104 , an adhesive tape T rolled on the rotating roll  101  is fed to the tape-cutting portion  30  and the tape-affixing portion  40  through the tape-feeding path  50 . While the adhesive tape T is fed, the adhesive surface of the adhesive tape T faces upwardly. 
     The rotating mechanism  104  rotates the small diameter disk  102  and the large diameter disk  103  at the same direction and rotating frequency. In this case, the large diameter disk  103  has an outer diameter larger than that of the small diameter disk  102 , whereby the circumferential speed of the adhesive tape T is higher at the large diameter disk  103  than at the small diameter disk  102 . According to such a difference between the circumferential speed at the small diameter disk  102  and the large diameter disk  103 , a back tension occurs at the distance P of the adhesive tape T shown in  FIG. 5A . On the other hand, the amount of the disposed small diameter disk  102  is larger than that of the disposed large diameter disk  103 , and the small diameter disk  102  contacts the adhesive tape T at a larger angle than the angle at which the large diameter disk  103  contacts the adhesive tape T. Therefore, the adhesive power with respect to the adhesive tape T at the small diameter disk  102  is larger than the adhesive power with respect to the adhesive tape T at the large diameter disk  103 , and the back tension occurs at the distance P, whereby the adhesive tape T is easily peeled off from the large diameter disk  103 . 
     As shown in  FIG. 5B , the lower side of the outer peripheral surface of the small diameter disk  102  is disposed at the flat portion  51 , and the adhesive tape T therebetween is thrust by the small diameter disk  102  and is fed in a flat shape in cross section. As shown in  FIG. 5C , the large diameter disk  103  is disposed to the concave portion  52 , and the adhesive tape T therebetween is thrust by the large diameter disk  103  and is fed in a downwardly convex curved shape in cross section. The adhesive tape T is fed while smoothly changing its shape in cross section from a flat shape to a curved shape along a tape-feeding direction at the connecting portion  53  between the small diameter disk  102  and the large diameter disk  103 . In the adhesive tape T in a curved shape, the extensibility is improved, and the buckling strength is increased. 
     The adhesive tape T fed from the tape-feeding portion  20  passes under the outer peripheral surface of the cylindrical portion of the workpiece W disposed on the workpiece-disposing groove  121 A in the tape-affixing portion  40 . As shown in  FIG. 8 , the adhesive tape T is cut by the tape-cutting portion  30  when it reaches the right end of the tape-feeding groove  54  of the guide plate  121  in the tape-affixing portion  40 . Specifically, the upper cutter  112  in a raised state, as shown in  FIGS. 7A and 7B , moves down toward the lower cutter  111  as shown in  FIG. 7C , whereby the adhesive tape T is cut. 
     In this case, because the adhesive surface of the adhesive tape T faces upwardly, the upper cutter  112  may adhere to the adhesive surface of the adhesive tape T. As shown in  FIG. 7C , when the adhesive tape T is cut, the suction member  114  synchronously moves down with the upper cutter  112  by friction occurred at the upper cutter  112 , and the suction opening  114 A is separated from the tape-feeding path  50 . As shown in  FIGS. 7A and 7B , after the adhesive tape T is cut, the suction member  114  is synchronously raised with the upper cutter  112  by friction occurring at the upper cutter  112 , and the suction opening  114 A returns to the tape-feeding path  50 . In this case, the reverse surface of the adhesive surface of the adhesive tape T that adhered to the upper cutter  112  is held by suction at the suction opening  114 A, whereby the adhesive tape T that adhered to the upper cutter  112  is peeled off therefrom. 
     Thus, the adhesive tape T is cut by the tape-cutting portion  30 , thereby obtaining the adhesive tape T having a length of L ( 2   l ) as shown in  FIG. 8 . In this case, the center of the adhesive tape T in the longitudinal direction is placed at the crossing portion of the tape-feeding groove  54  and the workpiece-disposing groove  121 A, and it corresponds to the center of the workpiece W. 
     In the tape-affixing portion  40 , the thrust member  122  is placed at the crossing portion of the tape-feeding groove  54  and the workpiece-disposing groove  121 A, and it is driven and raised by the lifting mechanism  123  as shown in  FIG. 9 . Then, while the claws  122 A and  122 B of the thrust member  122  elastically deform in accordance with the shape in cross section of the cylindrical portion of the workpiece W, they thrust the adhesive tape T on the outer peripheral surface of the cylindrical portion of the workpiece W passing through both sides of the outer peripheral surface of the cylindrical portion from below thereof so as to elevate the adhesive tape. Therefore, the adhesive tape T is affixed by fitting on the outer peripheral surface of the cylindrical portion of the workpiece W. Simultaneously, ends of the adhesive tape T are gradually raised along the tape-feeding groove  54  by drawing an arc which centers on the axis of the cylindrical portion of the workpiece W as double-dashed chain lines shown in  FIG. 9 . 
     After the claws  122 A and  122 B of the thrust member  122  pass the upper side of the outer peripheral surface of the cylindrical portion of the workpiece W, they return to the former shape by elastically deforming and continue to be raised. In this case, the cylindrical portion of the workpiece moves down inside of the hollow portion  122 C placed under the claws  122 A and  122 B. Simultaneously, the claws  122 A and  122 B hold ends of the adhesive tape T longer than the length of the outer peripheral surface of the cylindrical portion of the workpiece W and affix the adhesive surfaces thereof to each other. Therefore, the adhesive tape T is affixed to the cylindrical portion of the workpiece W in the form of a free-hanging tag. 
     As a workpiece W on which the adhesive tape T is affixed in the form of a free-hanging tag in this way, a stabilizer  200  for vehicles shown in  FIG. 11  may be mentioned. In the stabilizer  200  for vehicles, an adhesive tape  202 , which is an adhesive tape T printed with a barcode for identifying the product, is affixed to a torsion portion  201  that is a cylindrical portion in the form of a tag. 
     As mentioned above, in the embodiment, the cut adhesive tape T is thrust and is affixed to the outer peripheral surface of the cylindrical portion of the workpiece W in such a way that the claws  122 A and  122 B of the thrust member  122  pass through both sides of the outer peripheral surface of the cylindrical portion of the workpiece W from below thereof so as to elevate the adhesive tape in a condition in which the adhesive surface faces upwardly. Adhesive surfaces at ends of the cut adhesive tape longer than the length of the outer periphery of the cylindrical portion are pressed and are adhered to each other after the adhesive surface of the adhesive tape was thrust and was adhered to the outer peripheral surface of the cylindrical portion. Therefore, the adhesive tape T is affixed to the cylindrical portion of the workpiece W in the form of a free-hanging tag, and the workpiece W is upwardly pulled out after the adhesive tape T is affixed. Moreover, the adhesive tape T can be automatically affixed to the workpiece W, whereby the affixing time is reduced, and the workpiece W is handled with both hands. 
     Specifically, in the tape-feeding portion  20 , the adhesive tape T is fed to the cylindrical portion of the workpiece W by a simple structure in which the adhesive tape T rolled on the rotating roll  101  is fed by rotating the small diameter disk  102  and the large diameter disk  103 . Therefore, the apparatus can be formed with a simple structure. 
     A back tension occurs at the adhesive tape T between the small diameter disk  102  and the large diameter disk  103 , whereby the adhesive tape T is easily peeled off from the large diameter disk  103 . Therefore, the adhesive tape T can be smoothly fed. Moreover, the adhesive power with respect to the adhesive tape T of the large diameter disk  103  is less than the adhesive power with respect to the adhesive tape T of the small diameter disk  102 , whereby the adhesive tape T is very easily peeled off from the large diameter disk  103 . Accordingly, the adhesive tape T can be smoothly fed. 
     The adhesive tape T between the flat portion  51  and the outer peripheral surface of the small diameter disk  102  is fed in a flat shape in cross section, and the adhesive tape T between the concave portion  52  and the outer peripheral surface of the large diameter disk  103  is fed in a downwardly convex curved shape in cross section. Therefore, in the adhesive tape T, the extensibility may be improved, and the buckling strength may be increased. Accordingly, the adhesive tape T can be further smoothly fed. Moreover, in the tape-cutting portion  30 , the suction member  114  near the upper cutter  112  can peel off the adhesive tape T from the upper cutter  112  without causeing damage. 
     In addition, the adhesive tape T is disposed at the tape-feeding groove  54  of the guide plate  121 , and the workpiece is disposed at the workpiece-disposing groove  121 A of the guide plate  121 , whereby the cylindrical portion of the workpiece W may be accurately positioned perpendicular to the adhesive tape T. Moreover, the longitudinal length of the tape-feeding groove  54  and the position where the adhesive tape T is cut by the tape-cutting portion  30  are suitably designed, whereby the centers of the cylindrical portion of the workpiece W and the adhesive tape T may be accurately made to coincide. The two claws  122 A and  122 B of the thrust member  122  are raised along the through hole  121 B formed in a direction perpendicular to the crossing portion of the tape-feeding groove  54  and the workpiece-disposing groove  121 A, and the adhesive tape T shifts along the tape-feeding groove  54  when it is affixed by the two claws, whereby the adhesive tape T may be affixed without a displacement in the longitudinal direction and the width direction. In this case, the adhesive tape T is thrust by fitting to the outer peripheral surface of the cylindrical portion of the workpiece W, whereby the adhesive tape T may be affixed thereto while avoiding wrinkles. 
     (3) Variation of Embodiment 
     As mentioned above, the present invention is explained by the above embodiments, but the invention is not limited thereto and may be modified in various ways. For example, in the above embodiments, a stabilizer for vehicles is used as a workpiece W, but various members having cylindrical portion may be used. In the above embodiment, the cylindrical portion of the workpiece W has a circular shape in axial cross section, but this is not limited thereto and may have an approximately circular shape (for example, an oval shape). In the above embodiment, the adhesive tape T has a length longer than the length of the outer periphery of the cylindrical portion of the workpiece W, and it is affixed to the cylindrical portion of the workpiece W in the form of a free-hanging tag. Moreover, an adhesive tape T may have a length that is not more than the length of the outer periphery of a cylindrical portion of a workpiece W, and it may be affixed to only the outer peripheral surface of the cylindrical portion of the workpiece W.