Abstract:
When bolts are fastened to tack a door to a car body by means of a conventional impact wrench, the shavings stick to the surface of the door or car body, thereby to cause the poor coating quality such as a seeding when the inter-coating or finish-coating is performed in the coating procedure. An impact wrench provided is a fastening tool for fastening a bolt gripped by a socket, in a nut. The impact wrench includes a suction cover for covering the surroundings of the socket, and a suction port capable of sucking the atmosphere in the portion covered with the suction cover, and is constituted such that the atmosphere in the suction cover is sucked through the suction port to recover the shavings left at the time of fastening the bolt. This constitution makes it possible to prevent the shavings from being scattered to the surroundings. When the door is temporarily attached at the coating step to a car body, the poor coating quality such as the seeding, as might otherwise be caused by the shavings stuck to the surface of the car body or door, can be prevented and improved.

Description:
This is a 371 national phase application of PCT/JP2008/064796 filed 20 Aug. 2008, claiming priority to Japanese Patent Application No. 2007-220437 filed 27 Aug. 2007, the contents of which are incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The present invention relates to a fastening tool for fastening a gripped fastening member to a fastened member. 
     BACKGROUND OF THE INVENTION 
     In the popular product line of vehicles, after coating the vehicle body, the components are assembled to the body. In a coating step, with the door such as a front door or rear door separated from the body, the electrodeposition coatings are performed to the body and door, and temporarily attaching the door to the body, the second coating and finish coating are carried out to the body and door. 
     In such a case, in a subsequent assembling step, the door is detached and assembled to the body. 
     The door is bolted to the body when temporarily attached and assembled to the body, in which used for bolting is the fastening tool such as an impact wrench disclosed in JP H5-74770 U. 
     When fastening the bolt to the nut set in the body and temporarily attaching the door to the body, the flange formed at the bolt head has a contact with the door-side members having the electrodeposition coating film, whereby the coating film is shaved off and the shavings occur. 
     The nut arranged in the body also has the electrodeposition coating film, so that the bolt shaves the coating film, thereby causing the shavings. 
     Fastening the bolt in the nut is, for example, performed in such a way that the socket of the wrench covers and grips the bolt head, and the socket rotates. In the case, the shavings may occur by the contact of the socket with the bolt head. 
     Thus, when fastening the bolt using the fastening tool such as an impact wrench for attaching the door to the body, many shavings occur around the bolted portion. 
     On the other hand, in the coating step, in order to avoid the poor coating quality (e.g. seeding) caused by the coating such as second coating or finish coating with the dust adhered to the surface of the body or door, the coating operation is carried out in a clean environment such as in a clean room. 
     However, as mentioned above, the shavings occur when tacking the door to the body, and the shavings adhere to the surface of the body or door, which causes the imperfect coating such as the seeding in second coating or finish coating, so that it is preferable to avoid the adhesion of the shavings to the surfaces of the body and door when fastening the bolt in the nut for temporarily attaching the door to the body. 
     SUMMARY OF INVENTION 
     Problems to be Solved by the Invention 
     The objective of the present invention is to provide an unexpected fastening tool enabled to avoid adhering of the shavings, which are generated by fastening the bolt in the nut when attaching the work to the body, to the surfaces of the work and the body. 
     Means of Solving the Problems 
     The present invention is a fastening tool fastening a fastening member supported by a gripping member to a fastened member, and includes a cover for covering around the gripping member and a suction port for sucking an atmosphere surrounded by the cover, in which the gripping member rotates in a direction of fastening the fastening member, the gripping member comprises an internal opening formed in a shape in response to a head portion of the fastening member, the gripping member comprises a through hole communicating an inner side of the internal opening to an outer side thereof, and when fastening the fastening member, the internal opening is fitted to the head portion of the fastening member and the through hole faces the side of the head portion fitted in the internal opening. 
     The above structure allows sucking the atmosphere in the cover and to collect the shavings generated in fastening the fastening member through the suction port, thereby preventing the shavings from scattering around. 
     Therefore, at the coating step for the vehicle, when the door is temporarily attached by means of the fastening member to the body with which the fastened member is provided, the poor coating quality such as the seeding caused by the shavings adhered to the surface of the body or door can be prevented and the coating quality can be improved. 
     Furthermore, the above structure allows sucking the shavings generated in the area surrounded by the inner side of the gripping member via the through hole, thereby improving the collection efficiency for the shavings. 
     In the preferable embodiment of the present invention, the through hole is formed in a direction perpendicular to the rotating axis of the gripping member and the formed direction of the hole is inclined to an opposite side to the rotating direction with respect to a radiating direction from a rotation center of the gripping member. 
     Thus, it causes the shavings generated in the socket to enter the through hole and to be discharged through the through hole, thereby collecting the shavings efficiently. 
     In the other embodiment of the present invention, the wrench further includes a fan for generating airflow toward the suction port, arranged in the cover. 
     Thus, increasing the suction performance in the suction cover toward the port, the efficiency for collecting the shavings generated at the fastening of the bolt is improved. 
     Effect of the Invention 
     According to the present invention, prevented is the scattering of the shavings caused by the fastening of the fastening member to the fastened member. 
     Thus, at the coating step for the vehicle, when the door is temporarily attached by means of the fastening member to the body with which the fastened member is provided, the poor coating quality such as the seeding caused by the shavings adhered to the surface of the body or door can be prevented and the coating quality can be improved. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view illustrating an impact wrench as one embodiment of the fastening tool. 
         FIG. 2  is a sectional side view showing the head portion of the wrench covered with a body cover and a suction cover. 
         FIG. 3  is a perspective view illustrating a socket arranged in the head portion of the wrench. 
         FIG. 4  is a front view showing through holes formed in the socket. 
         FIG. 5  is a sectional side view showing the wrench sucking the shavings generated at fastening the bolt to the nut. 
         FIG. 6  is a front view showing the other embodiment of the through holes. 
         FIG. 7  is a sectional side view showing the other embodiment of the wrench having a fan, provided in the shaft, rotating together with the socket. 
         FIG. 8  is a sectional side view showing an impact wrench, in which the rotating axis of the socket is perpendicular to the longitudinal direction of the body. 
         FIG. 9  is a bottom view showing an impact wrench, in which the rotating axis of the socket is perpendicular to the longitudinal direction of the body. 
     
    
    
     DETAILED DESCRIPTION 
     The best mode for carrying out the present invention is described below, referring attached drawings. 
       FIG. 1  shows an impact wrench  1  as a fastening tool fastening a fastening member such as a bolt to a fastened member such as a nut, including a socket  6  for gripping the fastening member, a body  2  for supporting the socket  6  rotatably via a rotating shaft  5 , and a grip  3  extending from the body  2  for the operator to hold the wrench  1 . 
     The body  2  has a motor connected to the shaft  5  for driving the socket  6 , and the grip  3  has a trigger  7  for switching the drive of the motor. 
     In the wrench  1 , the rotating axis of the socket  6  (that is the axis of the shaft  5 ) is the same as the longitudinal direction (left and right direction in  FIG. 1 ) of the body  2 . 
     The outer periphery of the body  2  is covered with a body cover  11  from the side of the socket  6  (head portion) to the side of the grip  3  (base portion). 
     As shown in  FIG. 2 , the cover  11  is stuck to the body  2  at the middle  11   b  and the base end  11   c , whereby the sealing is secured between the body  2  and the cover  11 . 
     The cover  11  extends the leading end  11   a  from the body  2  toward the socket  6 , covering the surroundings of the shaft  5  with defining a space C around the shaft  5 . 
     The cover  11  is opened at the leading end. 
     The cover  11  has rigidity to a certain extent in that the cover maintains the shape self-supportingly, and has elasticity to a certain extent in that the sealing is secured between the body  2  and the cover  11  when stuck to the body  2 , for example the material of the cover  11  is the polyvinyl chloride. 
     The end  11   a  of the cover  11  is connected with a suction cover  12  extending toward the socket  6  and having a tubular shape at the tip thereof. 
     The suction cover  12  has a certain length from the end  11   a  of the cover  11  to the tip of the socket  6  or beyond the tip of the socket  6 , thereby the suction cover covering the tip of the shaft  5  and the periphery of the socket  6 . 
     In the embodiment, the end  11   a  of the cover  11  may be extended to the tip of the shaft  5  so that the suction cover  12  only covers the socket  6 . 
     Note that the suction cover  12  has a bellows structure stretching in the axis direction of the shaft  5 . 
     The end  11   a  of the cover  11 , which is arranged to form the space C around the shaft  5 , has a suction port  11   d  for sucking the atmosphere in the space C. 
     The suction port  11   d  may be connected with the hose communicated with the suction device, thereby being capable of sucking the atmosphere in the space C. 
     The space C is communicated with the inside surrounded by the suction cover  12 , so that suction through the suction port  11   d  makes it possible to suck the atmosphere in the cover  12 . 
     As depicted in  FIG. 3 , the socket  6  has an internal opening  6   a , which is formed in accordance with the bolt head to be engaged with the bolt head, and the socket  6  supports the bolt head fitted therein. 
     In this manner, the socket  6  grips the bolt head and rotates together with it. 
     The socket  6  has through holes  6   c  at the sides thereof, and the holes communicate the inner side of the opening  6   a  to the outer side  6   b  of the socket  6 . The holes  6   c  is drilled in the orthogonal direction to the rotating axis of the socket  6 . 
     As shown in  FIG. 4 , the socket  6  fastens the hexagon-headed bolt, and the opening  6   a  is formed in hexagonal shape in response to the shape of the head  51   a  of the bolt. 
     The holes  6   c  are formed in each side of the inner wall of the opening  6   a , and the formed direction of each hole  6   c  is radiated from the rotation center of the socket  6 . 
     In one embodiment shown in  FIG. 5 , when the door is attached to the body using the bolt  51 , the screw portion  51   c  of the bolt  51  is inserted into the hinge  60  of the door and the bolt  51  is fastened to the nut  70   a  of the body  70 , whereby the door is attached to the body  70  via the hinge  60 . 
     As mentioned above, when fastening the bolt  51  to the nut  70   a , the impact wrench  1  is used to fasten the bolt  51  as follows. 
     The opening  6   a  of the socket  6  is engaged with the head  51   a  of the bolt  51 , and pushing the trigger  7  makes the socket  6  rotated by the motor in the body  2 . In cooperated with the rotation of the socket  6 , the bolt  51  rotates to be fastened to the nut  70   a.    
     The hinge  60  is fastened to the body  70 , so that the door is attached to the body  70 . 
     Note that the door (including the hinge  60 ) and the body (including the nut  70   a ) have electrodepostion coating films. 
     When the wrench  1  fastens the bolt  51  and the door is attached to the body  70  having the coating film, the screw portion  51   c  of the bolt  51  shaves the coating film of the nut  70   a  of the body  70 , and at the same time, the flange  51   b  provided with the head  51   a  of the bolt  51  has a contact with the body  70 , so that the coating film of the body  70  is shaved off for generating the shavings at the side of the head  51   a  of the bolt  51 . 
     If the shavings scatter and adhere to the surfaces of the body  70  and the door, the poor coating quality such as the seeding occurs when performing the second coating or the finish coating at the coating step, so that the wrench  1  easily collects the shavings generated in fastening the bolt  51  to the nut  70   a  so as not to scatter around. 
     When the wrench  1  fastens the bolt  51  to the nut  70   a , the opening  6   a  of the socket  6  engages with the head  51   a  of the bolt  51  and the socket  6  is rotated, at the time that the socket  6  covers the bolt  51 , the tip of the cover  12  is contacted to the hinge  60 . 
     Mentioned above, the suction cover  12  has the certain length from the end  11   a  of the body cover  11  to the tip of the socket  6  or beyond the tip of the socket  6 , so that the tip of the suction cover  12  contacts to the hinge  60  and the suction cover  12  covers the head  51   a  of the bolt  51  and the socket  6  engaged with the head  51   a.    
     When fastening the bolt  51 , the atmosphere surrounding the socket  6  and the other members is sucked through the port  11   d  connected with the suction device. 
     The socket  6  and the surroundings are covered with the suction cover  12  and the atmosphere in the suction cover  12  is sucked when fastening the bolt  51 , as a result, the shavings generated at the side of the head  51   a  of the bolt  51  is are sucked through the port  11   d , thereby preventing the scattering around. 
     In such a case, the socket  6  has the holes  6   c , so that the shavings generated in the opening  6   a  of the socket  6  caused by the contact of the socket  6  to the head  51   a  of the bolt  51  are removed from the socket  6  through the holes  6   c  and sucked through the port  11   d  as well as the shavings generated at the periphery of the socket  6 . 
     The shavings sucked through the port  11   d  are collected by the suction device or captured by the filter disposed between the port  11   d  and the suction device. 
     The suction device for sucking the atmosphere surrounded by the suction cover  12  through the port  11   d  may be employed by a wondergun connected to the air pipes in the factory where the coating step is performed. 
     The wondergun utilizes the back pressure generated by the air in the air pipes to suck the atmosphere in the suction cover  12  through the hoses connected to the port  11   d.    
     As described above, the wrench  1  sucks the atmosphere in the suction cover  12  through the suction port  11   d  and collects the shavings generated when fastening the bolt  51 , thereby preventing the scattering of the shavings. 
     Thus, when temporarily attaching the door to the body  70  at the coating step, the poor coating quality is prevented such as the seeding caused by adhering of the shavings to the body  70  or the door, thereby improving the coating quality. 
     In the embodiment, the holes  6   c  of the socket  6  are, as shown in  FIG. 4 , formed as radiated from the rotation center of the socket  6  toward outside, and explained below is the advantageous embodiment of the holes  6   c.    
     For example, as depicted in  FIG. 6 , the formed directions of the holes are inclined by the angle θ to the opposite side to the rotating direction of the socket  6  with respect to the radiation direction from the center of the rotation axis of the socket  6 . 
     In other words, in this embodiment, the inner ends of the holes  6   c  are shifted toward the rotating direction with respect to the outer end, and the holes  6   c  direct at the directions inclined gradually from inside to outside by the angle θ to the opposite side to the rotating direction of the socket  6  with respect to the radiation direction. 
     In the above-described embodiment, in which the holes  6   c  are formed as radiated from the rotation center of the socket  6  as shown in  FIG. 4 , the rotating direction of the socket  6  is perpendicular to the formed directions of the holes  6   c , so that there may be the case that the shavings generated in the opening  6   a  are not removed through the holes  6   c  and left at the corners of the inside of the opening  6   a.    
     In the advantageous embodiment shown in  FIG. 6 , the formed directions of the holes  6   c  are inclined to the opposite direction to the rotation direction of the socket  6 , so that the angle which the rotating direction of the socket  6  and the formed directions of the holes  6   c  make is smaller than right angle; as a result, it becomes easier for the shavings to enter the holes  6   c  in accordance with the rotation of the socket  6 , and for the shavings generated in the opening  6   a  to be discharged through the holes  6   c.    
     Thus, leaving the shavings in the opening  6   a  of the socket  6  is prevented and the efficient collection of the shavings is provided. 
     In the preferable embodiment, in order to improve the efficiency for collecting the shavings generated at the fastening of the bolt  51 , the wrench  1  may include a fan for blowing toward the port  11   d  in the surrounded area with the suction cover  12 . 
     For example, as depicted in  FIG. 7 , the wrench  1  has a fan  31  in the shaft  5 , and the fan  31  rotates together with the socket  6 . 
     The fan  31  blows toward the body  2  from the socket  6  in the suction cover  12  when the socket  6  is rotated for fastening the bolt  51 , so that the airflow generated by the fan  31  toward the port  11   d  strengthens the airflow generated by the suction at the port  11   d  from the socket  6  to the body  2 . 
     Thus, increasing the suction performance in the suction cover  12  toward the port  11   d , the efficiency for collecting the shavings generated at the fastening of the bolt  51  is improved. 
     In the wrench  1  as above-described embodiment, the direction of the rotating axis of the socket  6  is the same as the longitudinal direction (left and right direction in  FIG. 1 ) of the body  2 , and  FIGS. 8 ,  9  show the wrench  1  as the other embodiment, in which the rotating axis of the socket  6  is orthogonal to the longitudinal direction (left and right direction in  FIGS. 8 ,  9 ) of the body  2 , being capable of collecting the shavings. 
     In the wrench  1  as depicted in  FIGS. 8 ,  9 , the body cover  11  covers the tip of the body  2 , and the tip of the cover  11  is connected to the suction cover  12  surrounding the socket  6 . The suction cover  12  has the bellows structure as the same as shown in  FIGS. 1 ,  2 . 
     The shavings generated at fastening the bolt  51  is collected by being sucked through the port  11   d  via the space between the suction cover  12  arranged at the tip of the cover  11  and the socket  6  and via the space C defined between the cover  11  and the body  2 . 
     Note that the cover  11  is stuck to the body  2  at the portion positioned closer to the base end than the port  11   d , and sucking through the port  11   d  allows to suck the atmosphere around the socket  6  covered with the suction cover  12 . 
     INDUSTRIAL APPLICABILITY 
     The fastening tool according to the present invention is applicable to the fastening tool for fastening the gripped fastening member to the fastened member, especially to the case that the shavings occur in the fastened member when fastening the fastening member to the fastened member.