Abstract:
The present invention provides an anti-misfit structure for a nail cartridge, which resolves the problems of a typical nail cartridge. For example, when a short collated nail is mistakenly inserted, it is likely lead to different triggering strength, and easier swinging and jamming of nail bodies against stability and safety. The swinging end of the spring of the nail cartridge is provided with a stopper. So, when the nailer head of a short collated nail is mistakenly inserted into the long nailer head dent, the stopper blocks the collated nail, thus preventing any misalignment and subsequent triggering of a nailer for higher stability and safety.

Description:
CROSS-REFERENCE TO RELATED U.S. APPLICATIONS 
   Not applicable. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   NAMES OF PARTIES TO A JOINT RESEARCH AGREEMENT 
   Not applicable. 
   REFERENCE TO AN APPENDIX SUBMITTED ON COMPACT DISC 
   Not applicable. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to a structure of a nail cartridge, and more particularly to an innovative anti-misfit structure for a nail cartridge. 
   2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98. 
   The nail cartridge is used to accommodate and guide collated nails. 
   The collated nails are rows of nail bodies linked by a connecting band. Given the currently available types of nailers, the present invention relates more particularly to a nailer with a T-shaped profile, namely, wherein the nails of the nailer have an expanded nail head. 
     FIG. 1  depicts the typical nail cartridge  10 , wherein a nail tank  11  is generally provided with a spring  12  to insert the collated nails for flexible positioning. According to the specified pattern of the nail body, the inlet  13  of the nail tank  11  is formed into a T-shaped inlet to match the collated nails for stable motion. The marketable nail bodies of collated nails are divided into two types. As such, upper and lower T-shaped inlets  131 ,  132  are located at inlet  13  of nail tank  11  in the nail cartridge  10 . If longer collated nails  20   a  are inserted, as shown in  FIG. 1 , the nail head  22   a  of nail body  21   a  aligns with the upper T-shaped inlet  131  for insertion. Otherwise, if shorter collated nails  20   b  are inserted, as shown in  FIG. 2 , the nail head  22   b  of nail body  21   b  aligns with lower T-shaped inlet  132  for insertion (as shown for the location of collated nails represented by the broken line in  FIG. 2 ). 
   This nail cartridge has disadvantages during application. If longer collated nails are inserted and if the maximum size of the inlet of the nail tank matches the longer collated nail, then it is impossible to load nails smoothly because any misalignment or directional errors would affect loading, as shown in  FIG. 1 . If shorter collated nails  20   b  are inserted and if inlet  13  of the nail tank  11  has upper and lower T-shaped inlets  131 ,  132 , then it is possible to load the shorter collated nails  20   b  smoothly into upper T-shaped inlet  131 , even with misalignment, as shown in  FIG. 2 . However, if shorter collated nails are triggered in such a state, the nail ejection strength is far below the expectation due to a longer distance between the bottom of nail body  21   b  and ejection hole of the nailer. Furthermore, the shorter collated nails triggered in such a state provide a bigger probability of deflection and jamming with increasing instability and risk to nailer applications. 
   Thus, to overcome the aforementioned problems of the prior art, it would be an advancement in the art to provide an improved structure that can significantly improve efficacy. 
   To this end, the inventor has provided the present invention of practicability after deliberate design and evaluation based on years of experience in the production, development and design of related products. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention includes a swinging end  62  of the spring  60  of nail cartridge  30  being provided with a stopper  70 . When the nail head  51   b  of a short collated nail  50   b  is mistakenly inserted into the long nail head dent  321 , the stopper  70  blocks the short collated nail  50   b . This blocking prevents misalignment and subsequent triggering, enabling a more stable and more safe nailer. 
   The present invention also includes an end wall  41  of nail tank  31  of the nail cartridge  30  being provided with a relief groove  42 . When triggering is finished, the collated nail shifts towards the outlet  40  until the nailer head stops at the end wall  41  of outlet. The end  54  of connecting band  53  exceeding the nail head  51   b  inserts into the relief groove  42 , ensuring that the nail head  51   b  stops at the end wall  41  of the outlet  40  for a correct triggering. 
   Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       FIG. 1  shows an isolated perspective view of long collated nails being installed into the nail cartridge. 
       FIG. 2  shows an exploded and isolated perspective view of short collated nails being correctly and incorrectly installed into the nail cartridge. 
       FIG. 3  shows an isolated perspective view of a spring when no collated nails are installed into the nail cartridge of the present invention. 
       FIG. 4  shows an exploded and isolated perspective view of the spring stopped by the stopper when the short collated nails are incorrectly installed into the nail cartridge, the short collated nails being misaligned. 
       FIG. 5  shows a top plan view of the short collated nails and spring of  FIG. 4 . 
       FIG. 6  shows an exploded and isolated perspective view of the present invention when short collated nails are aligned and inserted smoothly into the nail cartridge. 
       FIG. 7  shows a top plan view of the short collated nails and spring of  FIG. 6 . 
       FIG. 8  shows an exploded and isolated perspective of the present invention when the long collated nails are inserted into the nail cartridge. 
       FIG. 9  shows a cross-sectional view of the present invention when a relief groove is set on the end wall of a nail tank in the nail cartridge. 
       FIG. 10  shows a schematic view of the operation of the relief groove disclosed in  FIG. 9 , when the nail body of the collated nail is triggered. 
       FIG. 11  shows another schematic view of the operation of the relief groove disclosed in  FIG. 9 , when the connecting band of the triggered nail body of the collated nail inserts into the relief groove. 
       FIGS. 12-14  show isolated perspective views of the blocking by the spring stopper when the reverse nail cartridge enters the nail tank. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The features and the advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of a preferred embodiment of the present invention with reference to the accompanying drawings. 
     FIGS. 3 ,  4 , and  5  depict preferred embodiments of the anti-misfit structure for a nail cartridge of the present invention. The nail cartridge is a component of a nailer used to accommodate and guide collated nails. 
   The present invention includes a nail cartridge  30 , which has a nail tank  31 . One end of the nail tank is connected to outlet  40  of the nailer, as shown in  FIG. 10 . The other end of nail tank  31  is provided with an inlet  32  for insertion of preset collated nail. A long nailer head dent  321  and a short nailer head dent  322  are separately placed at top and middle sections of the inlet  32 . The long nailer head dent  321  is used for insertion of the nail head  51   a  of a longer collated nail  50   a , as shown in  FIG. 8 . The short nailer head dent  321  is used for the nail head  51   b  of a shorter collated nail  50   b , as shown in  FIG. 6 . The nail bodies  52   a ,  52   b  of the collated nail  50   a ,  50   b  are linked by left and right connecting band  53 , e.g. paper tape. 
   A spring or snapper  60  is mounted at one side of nail tank  31  of nail cartridge  30  slightly lower than the short nailer head dent  321 . The spring  60  includes a fixed end  61  and a swinging end  62 . The swinging end  62  normally protrudes towards the nail tank  31 , being directed towards a collated nail. 
   A stopper  70  protrudes from a top end of swinging end  62  of the spring. When the nail head  51   b  of a shorter collated nail  50   b  is mistakenly inserted into long nailer head dent  321  (as shown in  FIG. 4 ), the protruding height of stopper  70  is enough to stop the shorter collated nail so as to prevent misalignment of the collated nails during the nail loading process. 
   The stopper  70  is integrally formed by the swinging end  62  of the spring. For example, the spring  60  of the present invention is formed by the stopper  70  punched through sheet metal. 
   The stopper  70  may also be fabricated separately and then assembled at the swinging end  62  of the spring  60 . 
   Referring to  FIGS. 9 and 10 , a relief groove  42  is placed at end wall  41  linking the nail tank  31  of nail cartridge  30  and nailer outlet  40 , such that the connecting band  53  of collated nails  50   a ,  50   b  can be inserted. The relief groove  42  can be formed by two interval notch grooves, as shown in  FIG. 9 , at left and right sides of the collated nails. Referring to  FIG. 10 , when the nail body  52   b  at a top of the collated nail  50   b  is triggered to protrude from the outlet  40 , a space is formed. Meanwhile, the connecting band  53  of the triggered nail body  52   b  is forcibly split. Referring also to  FIG. 10 , after the triggering behavior is started, the collated nail  50   b  slips towards the outlet  40  to make up the vacancy until nail head  51   b  of nail body  52   b  is stopped at end wall  41  of the outlet  40 . In such case, if the end  54  of connecting band  53  exceeds the nail head  51   b , the collated nails are allowed to be inserted into relief groove  42 , ensuring that nail head  51  could be really stopped at the end wall  41  of the outlet  40  for correct positioning and triggering. 
   Based upon above-specified structure, the present invention operates as detailed herein. 
   Referring to  FIGS. 4 and 5 , when the nail head  51   b  of a short collated nail  50   b  is mistakenly inserted into the nail tank  31  from long nailer head dent  321 , the bottom of nail body  52   b  of the collated nail is stopped by the stopper  70  at a top of the swinging end  62  of spring  60  within the nail tank  31 . In such case, the bottom of collated nail cannot contact other positions of the spring  60  for pressing the swinging end  62 . So, the short collated nail  50   b  cannot be inserted, and this installation error can be found, thus preventing the misalignment phenomenon during nail loading. 
   Referring to  FIGS. 6 and 7 , when the nail head  51   b  of a short collated nail  50   b  is inserted into nail tank  31  from the short nailer head dent  322 , one side of the collated nail passes over the fixed end  61  of spring  60 . Then, the swinging end  62  is enabled to be pressed on the side wall of nail tank  31 , since the swinging end  62  of the spring  60  extends towards the nail tank  31 . In such a case, the stopper  70  fails to block off the short collated nail  50   b  with the motion of swinging end  62 , enabling the short collated nail  50   b  to be inserted into the nail tank  31  for correct loading. 
   Referring also to  FIG. 8 , the nail head  51   a  of a long collated nail  50   a  is inserted into the nail tank  31  from long nailer head dent  321 . Thus, it is possible to press the swinging end  62  of spring  60  into the nail tank  31  for correct nail loading, the same way as shown in  FIGS. 6 and 7 . 
   Furthermore, the spring  60  has a protruding stopper  70  on the top of swinging end  62 , so as to prevent the nailing process from “displacement”, and use the stopper  70  for blockage when the nail body is reversed (the rear side being switched to the front side) into the nail cartridge. As shown in  FIG. 12 , when the short collated nail  50   b  is placed into the nail tank  31  of the nail cartridge  30  in reverse, the bottom of nail body  52   b  is blocked by the protruding stopper  70  at the top of the swinging end  62  of the spring  60 , so that users can identify the mistake and correct the direction. As shown in  FIG. 13 , when the nail head  51   b  of the short collated nail  50   b  is placed in the nail tank  31  from the correct short nail head dent  322  in reverse, since the connecting band  53  of the short collated nail  50   b  is inclined forward, the top of the swinging end  62  of the spring  60  is blocked to prevent incorrect assembly. As shown in  FIG. 14 , when the long collated nail  52   a  is placed in the nailed tank  31  of the nail cartridge  30  in reverse, the nail body is inclined forward, and it is blocked by the protruding stopper  70  on the top of the swinging end  62  of the spring  60 , so that the reversed long collated nail  52   a  is unable to enter the nail tank  31 , thus achieving the purpose of preventing incorrect assembly.