Abstract:
A tape holding device for holding, on a wall, a roll of tape having a cylindrical inner surface, including: a base rod member capable of being supported on the wall in a cantilever state, the base rod member having a first mount end capable of being rotatably mounted to the wall, a second free end opposite to the first end, and an outer surface between the first end and the second end; and a clamping rod member connected coaxially to the second end of the base rod member; the clamping rod member including: a clamp element provided movably in a radial direction of the base rod member between an initial position where the clamp element does not project from the outer surface of the base rod member and a clamp position where the clamp element projects from the outer surface, the clamp element being capable of abutting the inner surface of the roll of tape at the clamp position to apply a pressure to the inner surface; and a pressing unit provided movably in an axial direction of the base rod member between a non-operative position where the pressing unit does not press the clamp element and an operative position where the pressing unit presses the clamp element to move the clamp element from the initial position to the clamp position and to make the clamp element generate the pressure.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a tape holding device for holding a roll of tape to be applied to a surface of a product, for example, a wafer, in order to protect the surface.  
         [0003]     2. Description of the Related Art  
         [0004]     A tape holding device for holding a roll of tape on a cantilever-type base rod is generally known and is disclosed in, for example, Japanese Unexamined Patent Publication (Kokai) No. 10-35612 (JP-A-10-35612). As shown in  FIG. 4 , a tape holding device  100  has a base rod  101  projecting horizontally via a boss  103  from a breast portion  105   b  of a vertically movable frame  105 . A roll of tape  104  having a protective tape  104   b  wound in a roll on a cylindrical core member  104   a  is attached to the base rod, and the roll of tape  104  is adapted to be held between a retaining ring  102  mounted to a free end of the base rod  102  and the boss  103  so as not to be detached.  
         [0005]     In this example of prior art, however, there is no means for absorbing the gap between the roll of tape  104  and the base rod  101 , and there is a problem that, depending on the variation of the inner diameter of the roll of tape  104 , the gap between the roll of tape  104  and the base rod  101  may become excessively large and may make instability of the roll of tape  104  unstable.  
         [0006]     In another example of tape holding device that overcomes above-mentioned problem, a screw, provided at the end of the base rod, is tightened so as to move the core provided on the base rod in radial outward direction and to exert internal pressure to the inner surface of the roll of tape to thereby hold the roll of tape stably on the base rod.  
         [0007]     In the tape holding device wherein a screw is tightened to move the core so as to hold the roll of tape, there is a problem that, each time a roll of tape is replaced to the base rod, the screw has to be removed and the removed screw has to be replaced and tightened again so that attaching/detaching of the roll of tape takes time and the device has thus poor workability.  
         [0008]     Further, there is another problem that the extent of tightening of the screw varies with workers and screw threads may be damaged by excessive tightening. Although it is also possible to use pneumatic means to move the core of the base rod in radial outward direction, this complicates the tape holding device and leads to an increase in cost.  
       SUMMARY OF THE INVENTION  
       [0009]     In view of above-described problem, it is an object of the present invention to provide a tape holding device that permits a roll of tape to be attached to the base rod easily with one action.  
         [0010]     In order to attain above object, in accordance with the present invention, there is provided a tape holding device for holding, on a wall, a roll of tape having a cylindrical inner surface, comprising: a base rod member capable of being supported on the wall in a cantilever state, the base rod member including a first mount end capable of being rotatably mounted to the wall, a second free end opposite to the first end, and an outer surface between the first end and the second end; and a clamping rod member connected coaxially to the second end of the base rod member; the clamping rod member comprising: a clamp element provided movably in a radial direction of the base rod member between an initial position where the clamp element does not project from the outer surface of the base rod member and a clamp position where the clamp element projects from the outer surface, the clamp element being capable of abutting the inner surface of the roll of tape at the clamp position to apply a pressure to the inner surface; and a pressing unit provided movably in an axial direction of the base rod member between a non-operative position where the pressing unit does not press the clamp element and an operative position where the pressing unit presses the clamp element to move the clamp element from the initial position to the clamp position and to make the clamp element generate the pressure.  
         [0011]     In the tape holding device described above, the force that pushes the pressing unit toward the basal end of the base rod is converted to the force pressing the clamp element in radial outward direction, and the clamp element is thereby moved in radial outward direction of the base rod so that the outer surface of the clamp element exerts pressure to the inner surface of the roll of tape so as to fix the roll of tape to the base rod. In this manner, variation of the inner diameter of the roll of tape can be absorbed, and the roll of tape can be easily attached to the base rod with one single action, and workability of attaching operation of roll of tape can be improved. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]     These and other objects and features of the present invention will become clearer from the following description of the preferred embodiments given with reference to the attached drawings, wherein:  
         [0013]      FIG. 1  is a partial sectional view showing a tape holding device according to an embodiment of the present invention;  
         [0014]      FIG. 2  is a partial sectional view showing the tape holding device of  FIG. 1  with a roll of tape clamped;  
         [0015]      FIG. 3  is a partial sectional view showing the tape holding device of  FIG. 1  with the roll of tape released from clamped state; and  
         [0016]      FIG. 4  is a perspective view showing an example of a tape holding device according to a prior art. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0017]     Specific examples of the present invention will be described below with reference to appended drawings showing embodiments thereof.  FIG. 1  is a sectional view showing a tape holding device according to an embodiment of the present invention. The tape holding device  1  of this embodiment has a base rod (base rod member)  10  projecting horizontally from a generally vertical wall portion  3  such as a frame in cantilever state for holding a roll of tape  2  fitted from outside ( FIG. 2 ), an unshown drive unit for rotating the base rod  10  about its axis, and a clamping rod (clamping rod member)  20  for clamping the roll of tape  2  by exerting internal pressure thereto. As shown in  FIG. 2 , the roll of tape  2  used has a protective tape  2   b  wound around a cylindrical core member  2   a  in a roll.  
         [0018]     The base rod  10  is composed of a cylindrical rod body  12  having a through-hole  14  at the center of an axis and a long rod shaft (shaft)  18  pressed into the through-hole  14  to be integrated to the rod body  12  in one unit. The rear end side (basal end side or first mount end) of the rod shaft  18  is supported on a bearing  5  with the end connected to a driving source of the drive unit to be rotated thereby. Front end side (distal end side or second free end) of the rod shaft  18  projects from the front end face of the rod body  12  to be inserted into a through-hole  29  of the clamping rod  20  connected to the front end of the rod body  12 . The base rod  10  and the clamping rod  20  are coaxially connected to each other via the rod shaft  18 .  
         [0019]     For the purpose of this specification, the concepts of “front” and “rear” are defined as follows. The term “front” refers to the distal end side (free end side) of the tape holding device  1  supported in cantilever state by the wall portion  3 . The term “rear” refers to the basal end side of the tape holding device  1 .  
         [0020]     The rod body  12  has sufficient length for holding the roll of tape  2  fitted from outside so as to disengage, and has a through-hole  14  for the rod shaft  18  to be inserted in the center. The basal end of the rod body  12  is rotatably supported to the wall portion  3  via a boss  4  that is tightly fastened to the wall portion  3  with a bolt  9 . The through-hole  14  is formed in a stepped shape corresponding to the size of the rod shaft  18  with small diameter in the rear end side and large diameter in the front end side. The small sized portion  14   a  in the rear end side is the portion for the rod shaft  18  to be pressed therein. By pressing the rod shaft  18  into the rod body  12 , the two components are integrated in one unit so as to be rotated together by the driving source. The large sized portion  14   b  in the front end side that follows the small sized portion  14   a  in the rear end side is formed in a size sufficient to accommodate two front and rear coil springs (resilient member)  7 ,  8  disposed around the rod shaft  18 .  
         [0021]     A cavity  16  is formed at position closer to the front end than the longitudinal midpoint of the rod body  12  and corresponding to the axial midpoint of the roll of tape  2  for accommodating a plurality of clamp dowels (clamp elements)  24  provided in circumferential direction of the rod body  12  so as to be movable in radial outward direction of the rod body  12 . The cavity  16  is formed in a shape corresponding to the clamp dowels  24  in communication with the through-hole  14 . The clamp dowels  24  are received in the cavity  16  and elastically supported by the front and rear coil springs  7 ,  8  at both axial sides of the clamp dowels  24 . The clamp dowels  24  are received in such a manner that they can project from and retreat into the outer circumferential surface  13  of the rod body  12 . As shown in  FIG. 3 , the outer circumferential portion of the dowels  24  is adapted to project in radial outward direction from the outer circumferential surface  13  of the rod body  12  to thereby exert pressure on the internal surface  2   c  of the roll of tape  2 .  
         [0022]     The drive unit has a motor as a driving source, a speed reduction gear for reducing the rotating speed of the motor to increase output torque, and a transmission mechanism for transmitting the diving force of the motor to the rod shaft  18 . Various mechanisms such as a gear transmission mechanism, a belt transmission mechanism, etc. can be employed for the transmission mechanism.  
         [0023]     The clamping rod  20  connected to the front end of the base rod  10  has the clamp dowels  24  received in the cavity  16  of the base rod  10 , and a dowel pressing member (pressing unit)  26  for pushing the clamp dowels  24  in radial outward direction via the coil spring  7 .  
         [0024]     The dowel pressing member  26  includes a body  27  mounted to the front end of the base rod  10  and having a pair of arms  28 ,  28  arranged in opposition to each other, a pressing piece  23  disposed at inside of the clamp dowels  24  in sliding engagement with the clamp dowels  24 , a coil spring (elastic member)  7  arranged between the body  27  and the pressing piece  23  and allowing the pressing piece  23  to move relative to the body  27  under elastic deformation of the coil spring  7 , and U-shaped grasping member  33  fastened and fixed to the front end of the body  27 .  
         [0025]     The outer circumferential surface of the body  27  is formed in a circular arc such that the maximum outer diameter has smaller dimension than the inner diameter of the roll of tape  2  and the outer diameter of the rod body  12 . At the axial center of the body  27 , a through-hole  29  in which front end side of the rod shaft  18  is inserted is formed in communication with the through-hole  14  of the rod body  12 .  
         [0026]     The pressing piece  23  and the clamp dowel  24  are in sliding contact with each other at the tapered surfaces  23   a ,  24   a  so as to move the clamp dowel  24  in the direction perpendicular to the direction of the movement of the pressing piece  23 .  
         [0027]     Thus, by the wedge action of the pressing piece  23 , a force that pushes the dowel pressing member  26  in axially rearward direction R of the rod shaft  18  is converted via the pressing piece  23  to a force that pushes the clamp dowel  24  in radial outward direction of the rod shaft  18 , whereby the clamp dowel  24  is moved in the direction perpendicular to the moving direction of the pressing piece  23  so that the outer circumferential portion of the clamp dowel  24  in the cavity  16  projects from the outer circumferential surface  13  of the rod body  12 . The pressing piece  23  can exert a large force, even with a small force of the pressing piece  23 , due to its wedge action, so as to abut the clamp dowel  24  against the inner surface  2   c  of the roll of tape  2  and to fix the roll of tape  2  reliably.  
         [0028]     An unshown engaging groove is formed on one of the tapered surface  23   a ,  24   a  of the pressing piece  23  and the clamp dowel  24 , and an unshown protrusion that engages with the engaging groove is formed on the other tapered surface, and the two surfaces come into sliding contact with each other with the protrusion engaged into the engaging groove. By the engagement of the engaging groove with the protrusion, the clamping rod  20  is rotated together with the base rod  10 .  
         [0029]     A pair of arms  28 ,  28  provided on the front side portion of the body  27  are separated from each other in order to provide a pair of locking pieces (locking element)  40 ,  40  to be described later and a slider (releasing element)  45  between a pair of arms  28 ,  28 . At the basal inner surface of a pair of arms  28 ,  28 , there is formed an engaging step  31  capable of being engaged with the distal end of a pair of locking pieces  40 ,  40  as locking elements.  
         [0030]     The rear side portion of the body  27  is formed in a size such that it can be inserted into the front end opening of the through-hole  14  of the rod body  12 . The rear end face of the body  27  abuts against the end of the coil spring  7 , so that the pressing force of the dowel pressing member  26  is transmitted via the coil spring  7  to the pressing piece  23 .  
         [0031]     The grasping member  33  is a member for an operator to grasp the dowel pressing member  26  for operation, and is fixed to the body  27  using fastening means such as a bolt  34 . An operator needs only to grasp the grasping member  33  and push or pull the grasping member  33  in order to move the clamp dowel  24  in radial direction of the base rod  10 .  
         [0032]     As shown in  FIG. 3 , by grasping the grasping member  33  and moving the dowel pressing member  26  in rearward direction R, the pressing piece  23  is moved via the coil spring  7  on the front side in rearward direction R, and the clamp dowel  24  pushed by the pressing piece  23  is moved in radial outward direction, so that the clamp dowel  24  exerts on internal pressure on to the inner surface  2   c  of the roll of tape  2  and the roll of tape  2  is thereby fixed to the base rod  10 . As the coil spring  7  on the front side always exerts biasing force to the pressing piece  23  in rearward direction, contact between the outer surface  24   b  of the clamp dowel  24  and the inner surface  2   c  of the roll of tape  2  is maintained. The coil spring  7  regulates the force applied to the inner surface  2   c  of the roll of tape  2  by the clamp dowel  24  with its own resilience so that the clamp dowel  24  pushes the inner surface  2   c  of the roll of tape  2  with a constant force. The coil spring  8  that elastically supports the pressing piece  23  on the rear side and biases the pressing piece  23  in forward direction F, is softer than the coil spring  7  (is set to have a smaller spring constant).  
         [0033]     As shown in  FIG. 2 , when the grasping member  33  is pulled in forward direction, the pressing piece  23  is moved in forward direction F and the clamp dowel  24  is moved in radial inward direction so that the outer surface  24   b  of the clamp dowel  24  is separated from the inner surface  2   c  of the roll of tape  2  and the roll of tape  2  becomes ready to be removed from the base rod  10 .  
         [0034]     As has been described above, the tape holding device  1  according to the present embodiment has the clamp dowel  24 , movable in the radial outward direction of the base rod  10 , and a clamping rod  20  that has the dowel pressing member  26  for pushing the clamp dowel  24  in radial outward direction of the base rod  10 , so that the force that pushes the dowel pressing member  26  toward the basal end side of the base rod  10  is converted to the force that pushes the clamp dowel  24  in the radial outward direction and can move the clamp dowel  24  in the radial outward direction of the base rod  10 , whereby the clamp dowel  24  exerts pressure on to the inner surface  2   c  of the roll of tape  2  and the roll of tape  2  can be easily attached to the base rod  10 .  
         [0035]     Further, the tape holding device  1  according to the present invention has a pair of locking pieces (locking elements)  40 ,  40  for stopping the return of the dowel pressing member  26  and a slider  45  (releasing element) for unlocking. As shown in  FIG. 1 , a pair of locking pieces  40 ,  40  are provided on the front end side of the rod shaft  18 . The locking piece  40  is punched from a resilient metal plate by a press and is formed into a curved shape. A pair of locking pieces  40 ,  40  are disposed in opposition to each other with the rod shaft positioned in between, and one end  40   a  is fastened to the front end side of the rod shaft  18  with a screw  42 , and the other end  40   b  extends from the end  40   a  on the basal end side of the rod shaft  18  so as to form a free end gradually curving outward. (In  FIG. 1 , a roller  48  rises up on the locking piece  40  so as to make it straight. The locking piece in curved state can be seen in  FIG. 3 .) The free end of each locking piece  40  is bent and formed into the shape of a hook that functions as an engaging end  40   c  to abut against the engaging step  31  of the dowel pressing member  26  (a pair of arms  28 ).  
         [0036]     A pair of locking pieces  40 ,  40  function as locking elements when, as shown in  FIG. 3 , the slider  45  is pulled in forward direction F and the dowel pressing member  26  is pushed in rear direction R, that is, when the roller  48  of the slider  45  does not rise up on the locking piece  40  and the distal end of the locking piece  40  is not bent outward. Thus, the locking elements of the tape holding device  1  are adapted to function when the roll of tape  2  is fixed to the base rod  10 .  
         [0037]     The releasing element is a slider  45  which reciprocates in the direction of the rod shaft  18  along the inner surface of a pair of arms  28 ,  28  of the dowel pressing member  26 . The slider  45  is composed of a sliding contact member  46  that moves along the inner surface of a pair of arms  28 ,  28 , a grasping member  47  fastened and fixed to the distal end of the sliding contact member  46  with a screw  49 , and a roller  48  that rises up on a pair of locking pieces  40 ,  40  on the rear end side of the sliding contact member  46 . The roller  48  is rotatably provided with a portion projecting inwardly from the inner surface of the sliding contact member  46 . This slider  45  is pushed rearward, as shown in  FIGS. 1 and 2 , to thereby bend the pair of locking pieces  40 ,  40  such that a pair of locking pieces is disengaged from the engaging step  31 .  
         [0038]     The slider  45  acts as follows. As shown in  FIG. 2 , with the dowel pressing member  26  pushed in rearward direction R, when an operator grasps the grasping member  47  and pushes the slider  45  in rearward direction R, the roller  48  rolls with the sliding contact member  46  in sliding contact with the inner surface of a pair of arms  28 ,  28 . When the slider  45  is pushed further in rearward direction R, the roller  48  rises up on the locking piece  40  against the spring force exerted due to the locking piece  40  bent outward. The locking piece  40  is then bent inward and the engaging end  40   c  of the locking piece  40  slips away from the engaging step  31  of the inner surface of a pair of arms  28 ,  28  and is disengaged. Thus, the clamping rod  20  (dowel pressing member  26 ) becomes ready to move in forward direction F, that is, in clamp releasing direction, and the roll of tape  2  becomes ready to be removed from the base rod  10 .  
         [0039]     Next, in order to actuate a pair of locking pieces  40 ,  40  so as to lock the clamping rod  20  (dowel pressing member), with the dowel pressing member  26  pushed in rearward direction R, as shown in  FIG. 3 , the slider  45  needs only to be pulled in forward direction F. Then, a pair of locking pieces  40 ,  40  can be enabled to function again. Thus, when the slider  45  is pulled in the forward direction F, the roller  48  that has risen up on the locking piece  40  rolls down and the locking piece  40  is elastically restored to its original shape by its own spring force. By the engagement of the engaging end  40   c  of the locking piece  40  curved outward with the engaging step  31  of the inner surface of a pair of arms  28 ,  28 , the roll of tape  2  is fixed to the base rod  10 .  
         [0040]     Thus, tape holding device  1  according to the present invention has a pair of locking pieces  40 ,  40  as locking elements, and by the engagement of the distal end of the locking piece  40  with the engaging step  31  formed on the inner surface of a pair of arms  28 ,  28  of the dowel pressing member  26 , return of the dowel pressing member  26  can be prevented. Further, the tape holding device  1  has a slider  45  as releasing element, so that the engagement of the engaging step  31  with the locking piece  40  can be thereby cancelled, and the roll of tape  2  can be easily removed from the base rod  10 .  
         [0041]     The present invention is by no means limited to the above-described embodiment, but can be implemented in various modifications without departing from the scope of the invention. For example, although the tape holding device  1  of the present embodiment has a drive unit, the construction without a drive unit is also possible. The locking pieces  40  and the slider  45  may also be suitably modified in design. Although the pressing piece  23  is biased by the front side coil spring  7  in rearward direction R, this coil spring  7  may be omitted and the end face of the dowel pressing member  26  may directly abut against the end face of the pressing piece  23 .