Abstract:
A quick-detachable blade guard mounting structure. The structure includes a mounting frame, a holding down member defining with one side of the mounting frame, a gap, a blade guard holder member insertable into the gap, a stop device adapted for stopping the blade guard holder member in the gap, a lever pivoted to the holding down member and adapted for moving between a first position to unlock the blade guard holder member and a second position to lock the blade guard holder member.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a table saw and, more specifically, to a quick-detachable blade guard mounting structure for table saw. 
   2. Description of the Related Art 
   A table saw is provided with a movable saw blade guard adapted for protecting the saw blade when not in operation. During the operation of the table saw, the saw blade guard is lifted and placed at one side. When the table saw turned off, the saw blade guard is closed to mask the saw blade. 
     FIG. 1  illustrates a table saw constructed according to the prior art. According to this design, the worktable  1  has an elongated slot through which the saw blade  2  protrudes over the top side of the worktable  1 . A holder frame  3  is provided at one end of the elongated slot. A blade guard  4  is pivoted to the holder frame  3  and adapted for protecting the saw blade  2 . The holder frame  3  has two longitudinal coupling slots  5  coupled to respective screw rods (not shown) at the bottom side of the worktable  1 . Two lock nuts  6  are respectively threaded onto the screw rods to lock the holder frame  3 . When fastened up, the lock nuts  6  force the holder frame  3  against the saw blade holder to which the saw blade  2  is pivoted. In order to save storage space during delivery of the table saw, the holder frame  3  shall be detached from the worktable  1 . However, during mounting or dismounting of the holder frame  3 , a tool should be used and inserted into the elongated slot of the worktable  1  to rotate each lock nut  6  forwards or backwards. Therefore, it takes much time to mount/dismount the holder frame  3 . 
   SUMMARY OF THE INVENTION 
   The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide a quick-detachable blade guard mounting structure, which enables the user to mount/dismount the saw blade guard quickly without the use of any tools. 
   To achieve this object of the present invention, the quick-detachable blade guard mounting structure comprises a mounting frame. A holding down member is provided at one end of the mounting frame and defines with the mounting frame a gap. The holding down member has a locating hole. A blade guard holder member is adapted for inserting into the gap and has a mounting hole and at least one stop portion in a lower part thereof. At least one stop device is adapted to stop the at least one stop portion of the blade guard holder member to hold the flat blade guard holder member in the gap in a predetermined position where the mounting hole of the flat blade guard holder member is axially aligned with the locating hole of the holding down member. A lever is pivoted to an outer side of the holding down member and moved relative to the holding down member between a first position and a second position. The lever has a first stop portion, which is aligned with the locating hole of the holding down member when the lever moved to the first position, and a second stop portion, which is aligned with the locating hole of the holding down member when the lever moved to the second position. A locking member is provided between the lever and the holding down member and has a shank and a head at one end of the shank. The shank is engaged into the locating hole of the holding down member when the head stopped at the first stop portion of the lever. The shank is engaged into the gap and the mounting hole of the flat blade guard holder member when the head stopped at the second stop portion of the lever. A spring member is provided between the holding down member and the lever and adapted for pushing the head the locking member toward the lever. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic drawing showing a table saw constructed according to the prior art. 
       FIG. 2  is an exploded view of a quick-detachable blade guard mounting structure according to the present invention. 
       FIG. 3  is an assembly view of the quick-detachable blade guard mounting structure according to the present invention. 
       FIG. 4  is a front view of  FIG. 3  showing the lever moved to the second position (the blade guard holder member locked). 
       FIG. 5  is a bottom view of FIG.  3 . 
       FIG. 6  is a side view of FIG.  3 . 
       FIG. 7  is a sectional view taken along line  7 — 7  of FIG.  4 . 
       FIG. 8  is a sectional view taken along line  8 — 8  of FIG.  4 . 
       FIG. 9  is a sectional view taken along line  9 — 9  of FIG.  4 . 
       FIG. 10  is a front view of the quick-detachable blade guard mounting structure showing the lever moved to the first position and the blade guard holder member disconnected from the mounting frame. 
       FIG. 11  is a sectional view taken along line  11 — 11  of FIG.  10 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to FIGS. from  2  through  6 , a quick-detachable blade guard mounting structure is a part of a table saw, comprising mounting frame  10 , a holding down member  20 , two cushions  30 , a lever  40 , two screw rods  50 ; 50 ′, a locking member  60 , a spring member  70 , and a blade guard holder member  80 . 
   The mounting frame  10  is mounted in the bottom side of the table of the table saw, having a pivot hole  11  in one side thereof for the mounting of a saw blade. The mounting frame  10  can be adjusted upwards to hold the saw blade in the cutting position partially above the top side of the table of the table saw, or downwards to hold the saw blade in the received position below the table of the table saw. The mounting frame  10  further comprises a vertical wall  12  extended from one side thereof remote from the pivot hole  11 , and two through holes  13 ; 14  horizontally extended through the vertical wall  12 . 
   The holding down member  20  is a plate member of certain thickness vertically disposed at an outer side relative to the vertical wall  12  of the mounting frame  10 , having two longitudinal blocks  21  protruded from the back sidewall thereof (see FIG.  8 ), two conical stop portions  211  respectively protruded from the top sides of the longitudinal blocks  21 , a locating hole  22  through the outer and inner sidewalls thereof between the longitudinal blocks  21 , two through holes  23 ; 24  respectively extended through the longitudinal blocks  21 , a flange  25  protruded from the outer sidewall around the locating hole  22 , two bottom flanges  26  bilaterally forwardly extended from the bottom side thereof at right angles and facing the mounting frame  10 , and an opening  27  defined between the bottom flanges  26  (see FIG.  5 ). 
   The cushions  30  are plate members of thin thickness, each having a top side bent at 45° into a sloping guide face  31 , a circular through hole  32  at the center corresponding to the locating hole  22  of the holding down member  20 , and two through holes  33 ; 34  equally spaced from the circular through hole  32  at two sides corresponding to the through holes  23 ; 24  of the holding down member  20 . The through holes  33 ; 34  are slightly greater than the longitudinal blocks  21  of the holding down member  20 . During installation, the cushions  30  are placed in between the vertical wall  12  of the mounting frame  10  and the holding down member  20  and reversely arranged in parallel, such that the sloping guide faces  31  define a substantially hopper-like mouth (see  FIG. 6 ) after the longitudinal blocks  21  have been respective engaged into the through holes  33 ; 34 . 
   The lever  40  is provided at an outer side of the holding down member  20  opposite to the cushions  30 , having a pivot hole  41  disposed in one end thereof, an arched slot  42  (see FIGS.  7  and  9 ), a stop strip  43  obliquely downwardly extended from one side thereof adjacent to the arched slot  42 , a first eyeleted stop portion  44  disposed in the stop strip  43  at a lower location relatively farther from the arched slot  42 , a second eyeleted stop portion  45  disposed in the stop strip  43  at a higher location relatively closer to the arched slot  42 , a smoothly arched bearing portion  46  disposed in the other end thereof remote from the pivot hole  41 , and a horizontal finger strip  47  outwardly extended from the top side thereof. 
   The two screw rods  50 ; 50 ′ are respectively inserted in proper order through the through holes  13 ; 14  of the mounting frame  10 , the through holes  33 ; 34  of the cushions  30 , and the through holes  23 ; 24  of the holding down member  20 , and then the first screw rod  50  is directly screwed up with a first nut  51  and, the second screw rod  50 ′ is inserted through the pivot hole  41  of the lever  40  and screw up with a second nut  52 . Thus, the lever  40  can be turned about the axis passing through the pivot hole  41  between the first position P 1  (see  FIG. 10 ) and the second position P 2  (see FIG.  4 ). The engagement of the screw rods  50 ; 50 ′ with the nuts  51 ; 52  keeps the lever  40 , the holding down member  20  and the cushions  30  closely attached to the vertical wall  12  of the mounting frame  10 , and also keeps the circular through holes  32  of the cushions  30  in line with the locating hole  22  of the holding down member  20  and one eyeleted stop portion  44  or  45  of the lever  40 . 
   The locking member  60  and the spring member  70  are provided between the lever  40  and the holding down member  20 , as shown in FIG.  2 . The locking member  60  comprises a shank  62  and a cone head  61  at one end of the shank  62 . The spring member  70  is a compression spring  70  sleeved onto the shank  62  of the locking member  60  and stopped between the head  61  of the locking member  60  and the flange  25  of the holding down member  20 , imparting an outward pressure to the head  61  of the locking member  60  toward the lever  40 . When the smoothly arched bearing portion  46  of the lever  40  touched the first nut  51 , the lever  40  is moved to the first position P 1 , at this time the head  61  is stopped at the first eyeleted stop portion  44 , and the shank  62  of the locking member  60  is inserted into the locating hole  22  of the holding down member  20  (see FIG.  11 ). When the lever  40  moved to the second position P 2 , the head  61  is stopped at the second eyeleted stop portion  45 , and the shank  62  is extended toward the mounting frame  10  farther. 
   Because of the arrangement of the spring member  70 , the gap between the cushions  30  varies with the compression status of the spring member  70 . 
   The blade guard holder member  80  is a flat coupling plate. The upper part of the blade guard holder member  80  is adapted for receiving a blade guard (not shown). The lower part of the blade guard holder member  80  comprises two longitudinal guide slots  82  arranged in parallel and extended to the bottom side thereof, a suspension portion  83  defined between the longitudinal guide slots  82 , and a mounting hole  81  disposed in the front suspension portion  83 . The bottom side of each longitudinal guide slot  82  is an open end. The top side of each longitudinal guide slot  82  is a close end, which forms a stop edge  821 . 
   Before inserting the lower part of the blade guard holder member  80  into the gap between the cushions  30 , the lever  40  is shifted to the first position P 1 , and then the bottom edge of the blade guard holder member  80  is aimed at the hopper-like mouth defined between the sloping guide faces  31  of the cushions  30 , keeping the bottom open sides of the longitudinal guide slots  82  aligned with the longitudinal blocks  21  of the holding down member  20 . Thus, the blade guard holder member  80  can be smoothly moved into position. When the stop edges  821  of the longitudinal guide slots  82  respectively stopped at the conical stop portions  211  of the longitudinal blocks  21  (see FIG.  8 ), the blade guard holder member  80  is prohibited from downward movement, and the front suspension portion  83  is plugged into the opening  27  between the bottom flanges  26  (see FIG.  5 ). When pushing the finger strip  47  to move the lever  40  from the first position P 1  to the second position P 2  at this time, the stop strip  43  will force the locking member  60  toward the mounting frame  10 , thereby causing the head  61  of the locking member  60  to be stopped at the second eyeleted stop portion  45  and the shank  62  engaged into the locating hole  22  and the mounting hole  81  to lock the blade guard holder member  80 . On the contrary, when removing the blade guard holder member  80 , push the finger strip  47  to move the lever  40  from the second position P 2  to the first position P 1 . When shifted to the first position P 1 , the locking member  60  is forced by the spring member  70  to disengage the shank  62  from the mounting hole  81  and to stop the head  61  at the first eyelet stop portion  44 , for enabling the user to remove the blade guard holder member  80  from the mounting frame  10 . 
   Further, when inserting the blade guard holder member  80  into the gap between the cushions  30 , the bottom flanges  26  of the holding down member  20  support the blade guard holder member  80  in position. 
   As indicated above, the quick-detachable blade guard mounting structure achieves numerous advantages as outlined hereinafter.
     1. By means of shifting the lever  40  between the first position P 1  (see  FIGS. 10 and 11 ) and the second position P 2  (see FIGS.  4  and  9 ), the blade guard holder member  80  is locked/unlocked. Therefore, it is not necessary to use any tools to lock/unlock the blade guard holder member  80 .   2. The longitudinal blocks  21  guide the front suspension portion  83  of the blade guard holder member  80  accurately into the opening  27  between the bottom flanges  26 , preventing vibration of the blade guard holder member  80 .   3. The parts of the blade guard mounting structure are simple and inexpensive to manufacture. When assembled, the blade guard holder member  80  can easily quickly be installed and locked.   4. By means of adding additional cushion(s) to the gap between the blade guard holder member  80  and the vertical wall  12  of the mounting frame  10  to change the position of the blade guard holder member  80  relative to the mounting frame  10 , the blade guard can be adjusted to the center position in perfect alignment with the saw blade.   

   While only one embodiment of the present invention has been shown and described, it will be understood that various modifications and changes could be made thereunto without departing from the spirit and scope of the invention disclosed.