Abstract:
A nail magazine for use in a power nailing hand tool to hold and feed a rolled belt of nails is constructed to include a casing, a magazine shaft vertically disposed inside the casing at the center, the magazine shaft having an upright shaft at the center inside the casing and a nail carrier sleeve vertically movably supported on a magazine spring around the upright shaft and adapted to carry a rolled belt of nails for feeding, and a cover hinged to the casing, the cover defining with the casing a nail feed hole when closed on the casing.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a nail magazine for use in a power nailing hand tool and, more particularly, to such a nail magazine, which is practical for use to feed L-shaped nails for fastening asbestos slats or light angle bars. 
   2. Description of the Related Art 
     FIG. 1  shows a conventional L-shaped nail for use in a power nailing hand tool to which the invention pertained. The L-shaped nail has a flat elongated nail body, an angled head extended from the top end of the nail body, a point extended from the bottom end of the nail body, and an upwardly extended and biased toothed strip on the middle. This design of L-shaped nail is suitable for fastening asbestos slats, thin-layer angle bars, and other thin-layer sheet materials. The flat body can easily be driven into the workpiece, preventing breaking of the workpiece. The toothed strip enhances the positioning of the nail body in the workpiece. When in use, L-shaped nails are fastened together by a belt or tape, and then the belt of nails is rolled up and loaded in the nail magazine of a power nailing hand tool for fastening. 
     FIG. 2  shows a nail magazine constructed according to the prior art and adapted to hold and feed round nails as shown in FIG.  3 . This structure of nail magazine comprises a casing with an upright center shaft, and a cover hinged to the casing and adapted to hold down a belt of nails in the casing around the upright center shaft. The casing has a nail feed hole for output of nails one after another. When viewed from one side after a belt of round nails has been rolled up, the heads of the nails at an outer layer are respectively supported below the heads of the nails of at an inner layer (see  FIG. 3 ). However, when a belt of L-shaped nails rolled up, the angled heads of the nails at an outer layer are respectively rested on the angled heads of the nails at an inner layer. Therefore, the conventional nail magazine shown in  FIG. 2  is not practical for feeding L-shaped nails. 
   SUMMARY OF THE INVENTION 
   The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a nail magazine, which is practical for feeding L-shaped nails. It is another object of the present invention to provide a nail magazine, which automatically adjust the position of the loaded belt of nails subject to the feeding of nails. 
   To achieve these and other objects of the present invention, the nail magazine is used in a power nailing hand tool to hold and feed a rolled belt of nails comprised of a plurality of substantially L-shaped nails fastened together by a belt, each nail of the belt of nails having a flat elongated nail body, an angled head extended from a top end of the nail body, a point extended from a bottom end of the nail body, and an upwardly extended and biased toothed strip on the middle of the nail body. The nail magazine comprises a casing; a magazine shaft vertically disposed inside the casing at the center, the magazine shaft comprising an upright shaft perpendicularly upwardly extended from the center of the bottom wall of the casing, and a nail carrier sleeve vertically movably mounted around the upright shaft and adapted to carry the rolled belt of nails and to support the angled heads of the nails of the inner layer of the rolled belt of nails; and a cover hinged to the casing, the cover defining with the casing a nail feed hole when closed on the casing. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a conventional L-shaped nail to be used in the nail magazine of the present invention. 
       FIG. 2  illustrates the structure of a nail magazine according to the prior art. 
       FIG. 3  is a schematic drawing showing the rolling arrangement of a belt of round nails according to the prior art. 
       FIG. 4  shows a conventional belt of L-shaped nails rolled up. 
       FIG. 5  is a perspective view showing the opened status of a nail magazine according to the present invention. 
       FIG. 6  is an exploded view of the magazine shaft for the nail magazine according to the present invention. 
       FIG. 7A  is a sectional view of the nail magazine before loading of nails according to the present invention. 
       FIG. 7B  is similar to  FIG. 7A  but showing one rolled belt of nails loaded. 
       FIG. 7C  is similar to  FIG. 7B  but showing the quantity of nails reduced, the rolled belt of nails lowered. 
       FIG. 8  is a schematic top plain view of a part of the present invention, showing the feeding of nails into the nail feed hole. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIGS. 5 ,  6 , and  7 A, a nail magazine in accordance with the present invention is shown comprising a casing  30 , a magazine shaft  40 , belts of nails  50 , and a cover  60 . 
   The casing  30  is a hollow circular open frame member having a vertical mounting rod  31  upwardly extended from the periphery at one side, a horizontal mounting rod  32  perpendicularly extended from the periphery at one peripheral open side thereof remote from the vertical mounting rod  31 , a retaining hole  35  in the periphery, a stepped nail feeding wall  33  in the peripheral open side, and a wear resistant guide face  34  at the bottom side of the stepped nail feeding wall  33 . The stepped nail feeding wall  33  defines an inwardly sloping upper tread  331 , a lower tread  332 , and a riser  333  between the upper tread  331  and the lower tread  332 . 
   The magazine shaft  40  is vertically located on the center inside the casing  30 , comprising a shaft  41  fixedly upwardly extended from the center of the bottom wall of the casing  30 , a tubular flange  42  formed integral with the periphery of the shaft  41  and defining with the periphery of the shaft  41  an annular groove  43 , a magazine spring  44  mounted in the annular groove  43  around the periphery of the shaft  41 , and a nail carrier sleeve  45  axially movably sleeved onto the and supported on the magazine spring  44  above shaft  41 . The tubular flange  42  has at least one, for example, two vertically extended and substantially h-shaped guide grooves  46  formed in the periphery. Each guide groove  46  comprises a top open end  462 , a short vertical section  461  downwardly extended from the top open end  462 , a long vertical section  464  vertically extended toward the bottom side of the tubular flange  42 , a transverse section  463  connected between the bottom end of the short vertical section  461  and an upper part of the long vertical section  464 , and a circular guide plate  48  fastened to the periphery of the nail carrier sleeve  45  and peripherally disposed in contact with the inside wall of the casing  30  to guide vertical movement of the nail carrier sleeve  45  smoothly and stably. The long vertical section  464  has two ends closed. The nail carrier sleeve  45  comprises at least one, for example, two raised portions  47  projected from the inside wall and respectively coupled to the guide grooves  46 . By means of inserting the raised portions  47  through the top open end  463  into the short vertical section  461  of each guide groove  46  and then rotating the nail carrier sleeve  45  relative to the tubular flange  43  through an angle to move the raised portions  47  through the transverse section  463  of each guide groove  46  to the respective long vertical section  464 , the nail carrier sleeve  45  is coupled to the tubular flange  43  and can be moved vertically up and down along the long vertical section  464  of each guide groove  46 . 
   Each belt of nails  50  is comprised of a plurality of substantially L-shaped nails fastened together by a belt or the like, each nail having a flat elongated nail body, an angled head extended from the top end of the nail body, a point extended from the bottom end of the nail body, and an upwardly extended and biased toothed strip on the middle (The nails of the belt of nails are of the conventional products, no reference signs or numbers are used in the drawings to indicate the angled head, nail body, point, and toothed strip of each nail). When rolling up one belt of nails  50 , the angled heads of the nails of an outer layer are respectively rested on the angled heads of the nails of an inner layer. After one belt of nails  50  has been rolled up, it is put in the casing  30  around the nail carrier sleeve  45  with the angled head of the nail at the center rested on the top side of the nail carrier sleeve  45 . In order to fit the configuration of the nails, the nail carrier sleeve  45  is made having a collar  49  around the periphery that prevents direction contact of the toothed strip of each nail of the belt of nails  50  with the periphery of the nail carrier sleeve  45 . 
   The cover  60  is fastened to the casing  30  by a hinge  62  and adapted to close the casing  30 , having a retaining rib  67  formed in the inside wall for engaging into the retaining hole  35  to lock the cover  60  to the casing  30 , a nail feeding wall  64  formed in the peripheral open side corresponding to the nail feeding wall  33  of the casing  30 . When the cover  60  is closed, the nail feeding walls  33  and  64  form a nail feed hole  65  (see  FIG. 8 ), and the flat inside top wall  66  of the cover  60  is pressed on the angled heads of the nails of the belt of nails  50 . The nail feeding wall  64  defines two triangular steps  641  and  642  and a vertical face  643  disposed between the steps  641  and  642 . 
   Referring to  FIG. 7A , when the nail magazine is empty, the magazine spring  44  supports the nail carrier sleeve  45  in the upper limit position where the raised portions  47  of the nail carrier sleeve  45  are respectively at the closed top ends of the long vertical sections  464  of the guide grooves  46 , and therefore the nail carrier sleeve  45  does not fall from the tubular flange  43 . 
   Referring to  FIG. 7B , after loading of one belt of nails  50  in the magazine shaft  40 , the lead end of the belt of nails  50  is pulled outward toward the nail feeding wall  33  of the casing  30 , for enabling the angled head of the first nail of the belt of nails  50  to be rested on the upper tread  331 , and then the cover  60  is closed to hold down the belt of nails  50 , keeping the toothed strips of the leading nails of the belt of nails  50  suspended in between the riser  333  and the vertical face  643 . 
   After the loading of a complete belt of nails  50 , the cover  60  is closed to hold down the loaded belt of nails  50 , and the magazine spring  44  is compressed. At this time, the raised portions  47  of the nail carrier sleeve  45  are moved to the closed bottom ends of the long vertical sections  464  of the guide grooves  46 , and the loaded belt of nails  50  are firmly supported in between the casing  30  and the cover  60 , keeping the leading nails in line with the nail feed hole  65 . As illustrated in  FIG. 8 , the triangular steps  641  and  642  provide the nail feed hole  65  with an output space having a width gradually reducing toward the outside, and the inwardly sloping tread  331  of the nail feeding wall  33  guides the nails of the loaded belt of nails  50  to move into the nailing position in the nail feed hole  65  smoothly. The wear resistant guide face  34  supports and guides the movement of the points of the nails of the loaded belt of nails  50 . 
   Referring to  FIG. 7C , when nails are driven out of the nail magazine one after another, the magazine spring  44  imparts an upward pressure to the sleeve  50 , and the circular guide plate  48  guides vertical movement of the sleeve  50  along the long vertical sections  464  of the guide grooves  46  subject to the feeding of the loaded belt of nails  50 , and therefore feeding nails are constantly maintained in line with the nail feed hole  65 . 
   Further, the arrangement of the guide grooves  46  must match with the pulling force of the feeding of the loaded belt of nails  50 , i.e., the rotary force employed to the nail carrier sleeve  45  upon feeding of the loaded belt of nails  50 . The pulling force of the feeding of the loaded belt of nails  50  cause the raised portions  47  to be moved in direction away from the transverse sections  463  of the guide grooves  46 , preventing disconnection of the raised portions  47  from the guide grooves  46  of the tubular flange  43 . 
   A prototype of nail magazine has been constructed with the features of  FIGS. 5˜8 . The nail magazine functions smoothly to provide all of the features discussed earlier. 
   Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.