Patent Abstract:
A compound miter saw includes a table on which a workpiece is placed, a miter saw unit supporting a saw blade, and a housing pivotally supporting the miter saw unit related to the table in such a manner that the miter saws unit is at least laterally pivotable. Further, the miter saw includes a bevel mechanism for selectively determining the lateral position of the miter saw unit at any of a plurality of pivoted positions, including a vertical position where the saw blade is positioned substantially vertically relative to the table, and leftward and rightward pivoted positions where the blade is inclined laterally leftwardly and laterally rightwardly from the vertical position. The bevel mechanism includes a movable rod and three fixed stop members, the rod being operable to move between a first rod position abutting one of the fixed stop members and a second rod position not abutting the one of the fixed stop members so as to permit the lateral pivotal movement of the miter saw unit. The first fixed stop member is disposed so that the rod abuts the first fixed stop member when the miter saw unit is at the vertical position. Similarly, the second fixed stop member is disposed so that the rod abuts the second fixed stop member when the miter saw unit is leftwardly pivoted at a first predetermined angle from the vertical position. Further, the third fixed stop member is disposed so that the rod abuts the third fixed stop member when the miter saw unit is rightwardly pivoted at a second predetermined angle from the vertical position.

Full Description:
This is a continuation, of application Ser. No. 09/109,515, filed Jul. 2, 1998, which is a continuation of prior application Ser. No. 08/798,896, filed Feb. 11, 1997, now U.S. Pat. No. 5,907,897, which is a continuation-in-part of U.S. Ser. No. 08/761,730, filed Dec. 5, 1996, U.S. Pat. No. 5,870,938. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to compound miter saws or other power operated equipment or machinery utilizing a cutter for performing working operations on a workpiece. More particularly, the present invention relates to improvements in the bevel stop mechanism for the bevel adjustment for such power operated equipment. 
     BACKGROUND OF THE INVENTION 
     Saws and other apparatuses designed for cutting or performing other working operations on a workpiece typically require adjustment mechanisms for moving the saw blade or cutting tool into an angular relationship to the workpiece. Examples of such equipment include cross-cut compound miter saws which are adapted for allowing the user to selectively move the saw blade into any of a number of positions or modes for square cutting, miter cutting, bevel cutting, or compound miter cutting where a combination miter angle and bevel angle are cut. In addition, some operations, such as dado cutting or shaping operations, for example, require the use of saw blades or other cutting or working devices of different shapes or sizes to be substituted for one another in order to perform the desired operation on the workpiece, whether the workpiece is composed of wood, plastic, metal other materials. 
     In order to allow for the adjustment in the miter and the bevel angle, the saw blade, cutter or other working device is angularly adjustable with respect to a horizontal base and a vertical fence against which the workpiece is positioned. The miter adjustment allows the saw blade, cutter or other working device to move angularly with respect to the vertical fence while maintaining perpendicularity with the horizontal base. The bevel adjustment allows the saw blade, cutter or other working device to move angularly with respect to the horizontal base while maintaining perpendicularity with the vertical fence. At times it may be desirable to cut a combination miter angle and bevel angle by simultaneously adjusting the angularity of the blade with respect to both the horizontal base and the vertical fence. 
     Once the saw blade, cutter or other working device has been adjusted to the desired position with respect to the horizontal base and the vertical fence, locking mechanisms for the miter and bevel adjustment must be activated in order to prohibit movement of the saw blade, cutter or other working device with respect to the base and fence while the cutting operation is performed. These locking mechanisms need to be easily activated, adjustable and quick acting in order to optimize the efficiency of the cutting apparatus and provide convenience to the operator of the apparatus. 
     It is also advantageous to provide bevel stop mechanisms so that operators can change and easily locate common bevel angles. These bevel stop mechanisms need to be easily engaged and disengaged, adjustable and quick acting in order to optimize the efficiency of the cutting apparatus and provide convenience to the operator of the apparatus. 
     SUMMARY OF THE INVENTION 
     In accordance with the present invention, an improved bevel stop is employed in a miter saw. The miter saw includes a table on which a workpiece is placed, a miter saw unit supporting a saw blade and having a motor for rotatably driving the saw blade, and a housing pivotally supporting the miter saw unit related to the table in such a manner that the miter saw unit is at least laterally pivotable. Further, the miter saw includes a bevel mechanism for selectively determining the lateral position of the miter saw unit at any of a plurality of pivoted positions including a vertical position where the saw blade is positioned substantially vertically relative to the table, and leftward and rightward pivoted positions where the blade is inclined laterally leftwardly and laterally rightwardly from the vertical position. 
     The bevel mechanism includes a movable rod and three fixed stop members, the rod being operable to move between a first rod position abutting one of the fixed stop members and a second rod position not abutting the one of the fixed stop members so as to permit the lateral pivotal movement of the miter saw unit. The first fixed stop member is disposed so that the rod abuts the first fixed stop member when the miter saw unit is at the vertical position. Similarly, the second fixed stop member is disposed so that the rod abuts the second fixed stop member when the miter saw unit is leftwardly pivoted at a first predetermined angle from the vertical position. Further, the third fixed stop member is disposed so that the rod abuts the third fixed stop member when the miter saw unit is rightwardly pivoted at a second predetermined angle from the vertical position. 
     Other advantages and objects of the present invention will become apparent to those skilled in the art from the subsequent detailed description, appended claims and drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings which illustrate the best mode presently contemplated for carrying out the present invention: 
     FIG. 1 is a front perspective view of a sliding compound miter saw in accordance with the present invention; 
     FIG. 2 is a front elevational view of the sliding compound miter saw shown in FIG. 1; 
     FIG. 3 is a rear elevational view of the sliding compound miter saw shown in FIGS. 1 and 2; 
     FIG. 4 is a side elevational view of the sliding compound miter saw shown in FIGS. 1 through 3; 
     FIG. 5 is an exploded perspective view of a first embodiment of the bevel stop mechanism in accordance with the present invention; 
     FIG. 6 is an assembled perspective view, partially in cross-section of the first embodiment of the bevel stop mechanism shown in FIG. 5; 
     FIG. 7 is a cross-sectional side view of the first embodiment of the bevel stop mechanism shown in FIG. 5; 
     FIG. 8 is an end view of the base or table assembly illustrating a first embodiment of the adjustment feature provided for the bevel stop mechanism shown in FIG. 5; 
     FIG. 9 is an end view of the base or table assembly illustrating a second embodiment of the adjustment feature provided for the bevel stop mechanism shown in FIG. 5; 
     FIG. 10 is an end view of the base or table assembly illustrating a third embodiment of the adjustment feature provided for the bevel stop mechanism shown in FIG. 5; 
     FIG. 11 is a partial cross-section perspective view of a second embodiment of the bevel stop mechanism; 
     FIG. 12 is a cross-sectional side view of the second embodiment of the bevel stop mechanism shown in FIG. 11; 
     FIG. 13 is a partial cross-section perspective view of a third embodiment of the bevel stop mechanism; 
     FIG. 14 is a cross-sectional side view of the third embodiment of the bevel stop mechanism shown in FIG. 13; 
     FIG. 15 is a partial cross-section perspective view of a fourth embodiment of the bevel stop mechanism; 
     FIG. 16 is a cross-sectional side view of the fourth embodiment of the bevel stop mechanism shown in FIG. 15; 
     FIG. 17 is a partial cross-section perspective view of a fifth embodiment of the bevel stop mechanism; 
     FIG. 18 is a cross-sectional side view of the fifth embodiment of the bevel stop mechanism shown in FIG. 17; 
     FIG. 19 is an end view of the base or table assembly illustrating the adjustment feature provided for the bevel stop mechanism shown in FIGS. 17 and 18; 
     FIG. 20 is a partial cross-section perspective view of a sixth embodiment of the bevel stop mechanism; 
     FIG. 21 is a cross-sectional side view of the sixth embodiment of the bevel stop mechanism shown in FIG. 20; 
     FIG. 22 is a partial cross-section perspective view of a seventh embodiment of the bevel stop mechanism; 
     FIG. 23 is a cross-sectional side view of the seventh embodiment of the bevel stop mechanism shown in FIG. 22; 
     FIG. 24 is a partial cross-section perspective view of an eighth second embodiment of the bevel stop mechanism; 
     FIG. 25 is a cross-sectional side view of the eighth embodiment of the bevel stop mechanism shown in FIG. 24; 
     FIG. 26 is an end view of the base or table assembly illustrating a ninth embodiment of the bevel stop mechanism; 
     FIG. 27 is an exploded side view of the pin assembly used in the ninth embodiment of the bevel stop mechanism shown in FIG. 26; 
     FIG. 28 is an exploded perspective view of the pin assembly used in the ninth embodiment of the bevel stop mechanism shown in FIG. 26; 
     FIG. 29 is a side view of the pin assembly used in the ninth embodiment of the bevel stop mechanism shown in FIG. 26, where FIG. 29 a  shows the pin assembly in the expanded position and FIG. 29 b  shows the pin assembly in the retracted position; 
     FIG. 30 is a cross-sectional side view of the rod assembly used in conjunction with the ninth embodiment of the bevel stop mechanism shown in FIG. 26; 
     FIG. 31 is a partial cross-section perspective view of a tenth embodiment of the bevel stop mechanism; 
     FIG. 32 is a cross-sectional side view of the tenth embodiment of the bevel stop mechanism shown in FIG. 31; 
     FIG. 33 is a cross-sectional view of the tenth embodiment of the bevel stop mechanism shown in FIGS. 31 and 32, along a line D—D shown in FIG. 32; 
     FIG. 34 is a partial cross-section perspective view of a eleventh embodiment of the bevel stop mechanism; 
     FIG. 35 is a cross-sectional side view of the eleventh embodiment of the bevel stop mechanism shown in FIG. 34; and 
     FIG. 36 is a cross-sectional view of the tenth embodiment of the bevel stop mechanism shown in FIGS. 34 and 35, along a line E—E shown in FIG.  35 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings in which like reference numerals designate like or corresponding parts throughout the several views, there is shown in FIGS. 1 through 4 an exemplary sliding compound miter saw incorporating a bevel stop mechanism according to the present invention, shown merely for the purposes of illustration, and designated generally by the reference numeral  10 . One skilled in the art will readily recognize from the following description, taken in conjunction with the accompanying drawings and claims, that the principles of the present invention are equally applicable to sliding compound miter saws, compound miter saws, chop saws, radial arm saws, table saws, jigsaws, scroll saws, or other saws of types other than that shown for purposes of illustration in the drawings. Similarly, one skilled in the art will readily recognize that the principles of the bevel stop mechanism according to the present invention are also applicable to other types of powered or unpowered equipment for performing an operation on a workpiece. Such equipment includes, but is not limited to, dado saws, spindle shapers or sanders, or other types of powered or unpowered devices that would benefit from the cam locking mechanism of the present invention. 
     Referring primarily to FIGS. 1 through 4, sliding compound miter saw  10  comprises a base assembly  12 , a table assembly  14 , a unique housing assembly  16 , a saw blade  18 , a blade guard  20 , a motor  22  drivingly connected to saw blade  18 , a handle  24  and a fence assembly  26 . Table assembly  14  is secured to base assembly  12  such that it can be rotated in order to provide adjustment for miter cutting. The rotation of table assembly  14  changes the angle of saw blade  18  relative to fence assembly  26  but maintains the perpendicularity of saw blade  18  with table assembly  14 . A locking mechanism  28  can be activated in order to lock table assembly  14  to base assembly  12 . 
     Housing assembly  16  is secured to table assembly  14  such that it can be pivoted with respect to table assembly  14  in order to provide adjustment for bevel cutting. As can be appreciated by one skilled in the art, the adjustments for mitering and beveling can be separate or they can be adjusted simultaneously in order to provide a compound miter and bevel cut. The pivoting of housing assembly  16  changes the angle of saw blade  18  relative to table assembly  14  but maintains the perpendicularity of saw blade  18  with respect fence assembly  26 . A locking mechanism  30  can be activated in order to lock housing assembly  16  to table assembly  14  at any desired bevel angle. 
     Referring to FIGS. 1 through 5, housing assembly  16  includes support housing  32 , which mounts a pair of support arms  34  for sliding movement with respect to housing  32 . Saw blade  18 , blade guard  20 , motor  22  and handle  24  are all mounted to a drive housing  36  which is pivotably secured to support arms  34 . The pivoting of drive housing  36  downward towards table assembly  14  operates to open blade guard  20  and cut a workpiece which is supported by table assembly  14  and fence assembly  26 . The sliding movement of support arm  34  relative to housing  32  permits drive housing  36  and thus saw blade  18  to be pulled through the workpiece when the size of the workpiece exceeds the cutting width of saw blade  18 . 
     Referring now to FIGS. 5 through 8, support housing  32  is pivotably supported with respect to table assembly  14  on a steel shaft  40  which is secured to table assembly  14  and extends rearwardly from table assembly  14  to define a pivot axis  42  for support housing  32 . Shaft  40  is inserted into a complimentary bore  44  located within table assembly  14  and is secured in place using a cross pin  46  which extends through a bore  47  extending through shaft  40  and a corresponding set of bores  48  located within table assembly  14  and being generally perpendicular to and extending into bore  44 . The end of shaft  40  opposite to the end defining bore  46  includes a threaded stub  50  for retaining and adjusting locking mechanism  30  as will be described later herein. 
     Locking mechanism  30  comprises a cam  52 , a handle  54 , a thrust bearing  55 , a plurality of washers  56  and a locknut  58 . Once support housing  32  is slidingly and pivotably received on shaft  40 , cam  52  is slidingly positioned on shaft  40  adjacent support housing  32 . Cam  52  includes a D-shaped through bore  60  which mates with a corresponding D-shaped portion  62  of shaft  40  such that cam  52  is allowed to move axially along portion  62  of shaft  40  but rotation of cam  52  with respect to shaft  40  is prohibited. Cam  52  further includes an angular camming surface  64  having a plurality of ramps which is located on the radial surface of cam  52  which is opposite to support housing  32 . Camming surface  64  is designed to mate with handle  54  as will be described later herein. 
     Handle  54  is slidingly and rotatably positioned on shaft  40  adjacent to and outboard of cam  52 . Handle  54  includes an angular camming surface  66  having a plurality of ramps which mates with angular camming surface  64  on cam  52 . Support housing  32 , cam  52  and handle  54  are retained on shaft  40  by thrust washer  55 , the plurality of washers  56  and locknut  58  which is threadingly received on stub  50  of shaft  40 . 
     When angular camming surface  64  and angular camming surface  66  are in full contact with each other as shown in FIG. 7, support housing  32  is free to pivot on shaft  40  to change the bevel angle of saw blade  18 . Once the desired bevel angle has been set, handle  54  is rotated with respect to shaft  40 . Rotation of handle  54  mis-aligns camming surfaces  64  and  66  pushing support housing  32  and cam  52  axially along shaft  40 . Support housing  32  contacts table assembly  14  and continued rotation of handle  54  forces support housing  32  into table assembly  14  locking the two components together. The locking of the two components together can be accomplished by rotating handle  54  in either a clockwise or a counter clockwise direction on order to misalign camming surfaces  64  and  66 . This bi-directional locking ability of handle  54  simplifies the adjustment of the bevel angle on opposite sides of center. An indicator plate  68  is bolted to support housing  32  to allow the user to set a specific bevel angle. Indicator plate  68  is provided with a pair of slots which allow for the zero adjustment of plate  68  as is well known in the art. 
     The present miter saw  10  also incorporates two additional features within housing assembly  16 . These two features are a detent system  70  and a positive stop system  72 . Detent system  70  includes a biasing spring  74  and a ball  76 . Biasing spring  74  and ball  76  are inserted into a blind aperture  78  located within support housing  32 . The ends of aperture  78  are formed over ball  76  such that ball  76  is retained within aperture  78  while being biased by spring  74  against the formed ends of aperture  78 . Table assembly  14  includes a pair of detents  80 , FIG. 8, which are formed into the face of table assembly  14 . The position of detents  80  are selected such that ball  76  will drop into detent  80  when the bevel angle for support housing  32  reaches 31.62° either side of center. A bevel angle of 31.62° is desired when miter saw  10  is being set to cut cove molding. While the present invention is illustrated as having only one pair of detents  80 , it is within the scope of the present invention to provide additional detents located at additional bevel angles which are commonly used if desired. 
     Referring to FIGS. 5 through 8, positive stop system  72  comprises a biasing spring  82 , a stop rod  84 , an override button  86  and an adjustable stop system  88 . Biasing spring  82  is inserted into a stepped aperture  90  extending through support housing  32  such that it abuts the step formed within aperture  90 . Stop rod  84  is then inserted through spring  82  and through aperture  90  trapping spring  82  between rod  84  and stepped aperture  90 . A reduced diameter portion  92  of rod  84  extends through housing  32  and is inserted into a slot  94  formed within override button  86 . Override button  86  is pivotably secured to a pair of posts  96  formed as a part of housing  32  by a pair of bolts  98 . Once secured to posts  96 , pivoting movement of button  86  moves stop rod  84  axially within housing  32  between a stop position and a release position with spring  82  biasing stop rod  84  into its stopped position. 
     Persons skilled in the art will recognize that the spring  82  shown in FIGS. 6 and 7 is a compression spring. Additionally, such persons will recognize that the same function, i.e., biasing stop rod  84  into its stopped position, can be achieved by springs disposed on the button  86  which bias the button towards the stopped position. Further, persons skilled in the art will recognize that other means, such as elastomeric materials and structures, can be utilized to bias the stop rod  84  into its stopped position. 
     Additionally, persons skilled in the art will recognize that the stop rod  84  moves axially in a direction parallel to the axis of rotation  42 . However, such persons will also recognize that the stop rod  84  can be inclined in any manner, so long as it can contact the bolt  100 . 
     When located in its stopped position, stop rod  84  extends out of housing  32  and into table assembly  14  such that it can engage one of the plurality of adjustable stops  88   a  shown in FIG.  8 . Table assembly  14  is shown having an adjustable stop  88   a  located at a 0° bevel angle and at a bevel angle of 45° on both sides of center. Each adjustable stop  88   a  includes a housing  98  and a threaded stop bolt  100 . Each housing  98  is shown as an integral part of table assembly  14  but it is within the scope of the present invention to manufacture individual housings  98  and secure them to table assembly  14  if desired. Each housing  98  defines a threaded through bore  102  into which stop bolt  100  is threadably received. Threaded stop bolt  100  provides a surface for stop rod  84  to contact when the bevel angle of housing  32  is located at about 0° or about ±45° from the 0° bevel angle as is shown in the preferred embodiment. The adjustability of each stop  88   a  is provided by the threaded connection between bolt  100  and housing  98  and this adjustability allows the operator to accurately set these specific bevel angles. When the bevel angle needs to be changed, handle  54  is rotated to release housing  32  from table assembly  14  and override button  86  is pivoted on posts  96  to withdraw stop rod  84  from within table assembly  14  to a position at which stop rod  84  does not contact bolt  100  or housing  98  when housing  32  is pivoted on shaft  40 . 
     Persons skilled in the art will recognize that the adjustable stops  88   a  may be replaced with fixed castings on the table assembly  14 . This will provide a mechanism to stop the stop rod  84  at a lower manufacturing cost. 
     The table assembly  14  may further be provided with a ramp  150 . The ramp  150  contacts the stop rod  84  when the miter saw is beveled in a clockwise direction M, i.e., from the −45° bevel angle towards the +45° bevel angle, so that the stop rod  84  retracts and bypasses the 0° bolt. 
     FIG. 9 illustrates a different adjustable stop system  88 , which can be used in conjunction with the other elements of the positive stop system  72 . Table assembly  14  is shown having an adjustable stop  88   a  located at about a bevel angle of 45° on both sides of center, having the same function and adjustability as described above. In addition, an adjustable guide plate  113  is provided to stop the stop rod  84  when the bevel angle of the housing  32  is located at about 0°. The guide plate  113  is preferably connected to an adjustment bolt  110 . 
     The adjustment bolt  110  includes a housing  112 . Each housing  112  is shown as an integral part of table assembly  14  but it is within the scope of the present invention to manufacture individual housings  112  and secure them to table assembly  14  if desired. Each housing  112  defines a threaded through bore  111  into which bolt  110  is threadably received. The adjustability of the adjustment bolt  110  (and thus of the guide plate  113 ) is provided by the threaded connection between bolt  100  and housing  98 . This adjustability allows the operator to accurately set the position of the guide plate  113 , and thus the specific bevel angle. 
     The table assembly  14  may further be provided with ramps  150   a . The ramps  150   a  contact the stop rod  84  when the miter saw is beveled back to the vertical position, i.e., from the ±45° bevel angles to the 0° bevel angle, so that the stop rod  84  retracts and slides onto guide plate  113 . The stop rod  84  then engages the guide plate  113  by extending into hole  113   a . When the bevel angles needs to be changed, handle  54  is rotated to release housing  32  from table assembly  14  and override button  86  is pivoted on posts  96  to withdraw stop rod  84  from within table assembly  14  to a position at which stop rod  84  does not engage guide plate  113  via hole  113   a when housing  32  is pivoted on shaft  40 . 
     FIG. 10 illustrates yet another adjustable stop system  88 , which can be used in conjunction with the other elements of the positive stop system  72 . Like the stop system shown in FIG. 9, this system has an adjustable guide plate  115 . The guide plate  115  is preferably connected to at least one adjustment bolt  110 . Unlike the guide plate  113 , the guide plate  115  has a plurality of holes  115   a,  for the stop rod  84  to contact when the bevel angle of housing  32  is located at about 0° or about ±45° from the 0° bevel angle. Nevertheless, operation of the system is substantially similar to the stop system of FIG.  9 . 
     Referring to FIGS. 11 and 12, a second embodiment of positive stop system  72  comprises a biasing spring  82 , a stop rod  84 , an override handle  114  and a stop system, preferably one of the stop systems shown in FIGS. 8 through 10. Biasing spring  82  is inserted into a stepped aperture  90  extending through the housing  32  such that it abuts the step formed within aperture  90 . Stop rod  84  is then inserted through spring  82  and through aperture  90 . The housing  32  has a plaque  117 , which may be built separate to or integrated with the housing  32 . Spring  82  is trapped between plaque  117  and the stop rod  84 . 
     A reduced diameter portion  92  of rod  84  extends through housing  32  and is inserted through a slot in plaque  117 . An override handle  114  is then attached to the portion of rod.  84  extending through plaque  117 . 
     Further, stop rod  84  has a helical groove  116  disposed on its body, that engages a stop  115  in housing  32 . Accordingly, rotational movement of handle  114 , for example,in a clockwise direction, i.e., along direction A, rotates stop rod  84 . Because of the engagement between the stop  115  and the rod groove  116 , stop rod  84  moves axially while rotating, as in a screwing action, within housing  32  between a stop position and a release position with spring  82  biasing stop rod  84  into its stopped position. 
     Persons skilled in the art will recognize that the spring  82  shown in FIGS. 11 and 12 is a compression spring. Additionally, such persons will recognize that the same function, i.e., biasing stop rod  84  into its stopped position, can be achieved by rotational springs disposed on the stop rod  84  and/or handle  114 , which force the rod  84  to rotate towards the stopped position. Further, persons skilled in the art will recognize that other means, such as elastomeric materials and structures, can be utilized to bias the stop rod  84  into its stopped position. 
     Referring to FIGS. 13 and 14, a third embodiment of positive stop system  72  comprises, like the embodiment illustrated in FIGS. 11 and 12, a biasing spring  82 , a stop rod  84 , an override handle  114  and a stop system, preferably one of the stop systems shown in FIGS. 8 through 10. The arrangement and operation of the third embodiment is similar to the one illustrated in FIGS. 11 and 12. Accordingly, the description of the second embodiment should be referred to when studying this embodiment. 
     Unlike in the second embodiment, a separate stop  119  is preferably disposed in the housing  32 . Spring  82  is then trapped between stop  119  and the stop rod  84 . Further, the helical groove  116  is disposed towards the rear of stop rod  84 , so that it can engage a stop  118  disposed in plaque  117 . Nevertheless, operation of the third embodiment is similar to that of the embodiment shown in FIGS. 11 and 12. 
     Referring to FIGS. 15 and 16, a fourth embodiment of positive stop system  72  comprises, like the embodiment illustrated in FIGS. 11 and 12, a biasing spring  82 , a stop rod  84 , an override handle  114  and a stop system, preferably one of the stop systems shown in FIGS. 8 through 10. The arrangement and operation of the fourth embodiment is similar to the one illustrated in FIGS. 11 and 12. Accordingly, the description of the second embodiment should be referred to when studying this embodiment. 
     Unlike in the second embodiment, plaque  117  is provided with guide  120 . Furthermore, stop rod  84  is provided with two pins  121 , which form a channel, or thread, that engages guide  120 . The combination of the pins  121  and guide  120  provide the same function as the combination of the helical groove  116  and stop  115 , i.e., convert rotational handle movement into axial stop rod movement. Accordingly, operation of the fourth embodiment is similar to that of the embodiment shown in FIGS. 11 and 12. 
     Referring to FIGS. 17 through 19, a fifth embodiment of positive stop system  72  comprises a biasing spring  182 , a stop rod  84 , an override handle  114  and a stop system  88 , preferably the stop system shown in FIG.  8 . Biasing spring  182  is attached to stop rod  84  at one end and to the housing  32  at another end. 
     The housing  32  has a plaque  117 , which may be built separate to or integrated with the housing  32 . A reduced diameter portion  92  of rod  84  extends through housing  32  and is inserted through a slot in plaque  117 . A handle  114  is then attached to the portion of rod  84  extending through plaque  117 . 
     Further, stop rod  84  has a radial groove  123  disposed on its body, that engages a stop  115  in housing  32 . The combination of the groove  123  and the stop  115  ensure that the rod  84  moves rotationally, rather than axially. Persons skilled in the art will recognize other means to achieve the same function. 
     Stop rod  84  has a step  122  at its distal end. As shown in FIG. 19, the step  122  is provided so that, upon rotation of rod  84 , the step  122  will either bypass or contact the stop  88   a . The spring  182  biases the rod  84  towards a contacting position. 
     Accordingly, when the bevel angle needs to be changed, handle  54  is rotated to release housing  32  from table assembly  14  and override handle  114  is rotated, for example, in a counter-clockwise direction, i.e., along direction B, to rotate step  122  to a position at which step  122  does not contact bolt  100  or housing  98  when housing  32  is pivoted on shaft  40 . 
     Persons skilled in the art will recognize that the spring  182  shown in FIGS. 17 and 18 is a rotational spring. Additionally, such persons will recognize that the same function, i.e., biasing stop rod into its stopped position, can be achieved by rotational springs disposed on the handle  114 , which force the step  122  to rotate into contact with the stops  88   a . Further, persons skilled in the art will recognize that other means, such as elastomeric materials and structures, can be utilized to bias the stop rod  84  into its contacting position. 
     Referring to FIGS. 20 and 21, a sixth embodiment of positive stop system  72  comprises a biasing spring  123 , a stop rod  84 , an override lever  186  and a stop system  88 , preferably the stop system shown in FIG.  8 . The stop rod  84  is disposed between pivot points  124  and  125 . As shown in FIGS. 20 and 21, the housing includes two inclined surfaces  90   a  and  90   b,  which in conjunction with pivot points  124  and  125 , allow radial movement of the stop rod  84  about the pivot points. Biasing spring  123  is attached to stop rod  84  at one end and to the housing  32  at another end. 
     A reduced diameter portion  92  of rod  84  extends through housing  32  and is inserted through a slot  94  in override lever  186 . The lever  186  has a lower lip  186   a,  which contacts the portion  92 . In addition, the lever  186  is slidably attached to posts  96 . 
     Accordingly, when the bevel angle needs to be changed, handle  54  is rotated to release housing  32  from table assembly  14  and override lever  186  is pulled in an upward direction, i.e., along direction Z, to rotate rod  84  about pivot points  124  and  125  to a position at which rod does not contact bolt  100  or housing  98  when housing  32  is pivoted on shaft  40 . 
     Persons skilled in the art will recognize that the spring  182  shown in FIGS. 17 and 18 is a compression spring. Additionally, such persons will recognize that the same function, i.e., biasing stop rod  84  into its stopped position, can be achieved by linear spring pushing or pulling lever  186 . Further, persons skilled in the art will recognize that other means, such as elastomeric materials and structures, can be utilized to bias the stop rod  84  into its stopping position. 
     Referring to FIGS. 22 and 23, a seventh embodiment of positive stop system  72  comprises, like the embodiment illustrated in FIGS. 20 and 21, a biasing spring  123 , a stop rod  84 , an override lever  186  and a stop system, preferably the stop system shown in FIG.  8 . The arrangement and operation of the seventh embodiment is similar to the one illustrated in FIGS. 20 and 21. Accordingly, the description of the sixth embodiment should be referred to when studying this embodiment. 
     Unlike in the sixth embodiment, pivot points  124  and  125  are not present. Instead, the stop rod  84  has a pivot pin  126  about which the stop rod  84  rotates. Accordingly, operation of the seventh embodiment is similar to that of the embodiment shown in FIGS. 20 and 21. 
     Referring to FIGS. 24 and 25, an eighth embodiment of positive stop system  72  comprises a biasing spring  123 , a stop rod  84 , an override lever  127  and a stop system  88 , preferably the stop system shown in FIG.  8 . The stop rod  84  is connected to the override lever  127  at a pivot axis  127   a.  As shown in FIGS. 20 and 21, the housing includes an inclined surface  90   b , which in conjunction with radial movement of override lever  127  about pivot axis  127   a,  allows radial movement of the stop rod  84  about the pivot axis  127   a . Biasing spring  123  is attached to stop rod  84  at one end and to the housing  32  at another end. 
     Accordingly, when the bevel angle needs to be changed, handle  54  is rotated to release housing  32  from table assembly  14  and override lever  127  is rotated, for example, in a clockwise direction, i.e., along direction Y, to rotate rod  84  about pivot axis  127   a  to a position at which rod does not contact bolt  100  or housing  98  when housing  32  is pivoted on shaft  40 . 
     Persons skilled in the art will recognize that the spring  123  shown in FIGS. 24 and 25 is a compression spring. Additionally, such persons will recognize that the same function, i.e., biasing stop rod  84  into its stopped position, can be achieved by a rotational spring pushing or pulling lever  127 . Further, persons skilled in the art will recognize that other means, such as elastomeric materials and structures, can be utilized to bias the stop rod  84  into its stopping position. 
     Referring to FIGS. 26 through 30, positive stop system  72  comprises a biasing spring  82 , a stop rod  84 , and an overridable, adjustable stop system  88 ′. Biasing spring  82  is inserted into a stepped aperture  90  extending through support housing  32  such that it abuts the step formed within aperture  90 . Stop rod  84  is then inserted through spring  82  and through aperture  90  trapping spring  82  between rod  84  and stepped aperture  90 . 
     The housing  32  has a plaque  117 , which may be built separate to or integrated with the housing  32 . A reduced diameter portion  92  of rod  84  extends through housing  32  and is inserted through a slot in plaque  117 . 
     When located in its stopped position, stop rod  84  extends out of housing  32  and into table assembly  14  such that it can engage one of the plurality of adjustable stops  88   c  shown in FIG.  26 . Table assembly  14  is shown having an adjustable stop  88   c  located at about a 0° bevel angle and at a bevel angle of about 45° on both sides of center. 
     Each adjustable stop  88   c  preferably has a threaded body  131 , a stop pin  128  disposed within the threaded body  131 , and a pin  129  at a distal end of the stop pin  128 . In addition, the adjustable stop  88   c  preferably has a spring  130  disposed between the stop pin  128  and the threaded body  131 . The threaded body  131  preferably has a long channel  132 , along which the pin  129  can slide. 
     As shown in FIG. 29 b , the stop pin  128  can be retracted by pulling out the stop pin  128  from the threaded body  131 , until the pin  129  contacts the end of the channel  132 . In order to put the stop pin  128  in the stopping position, the stop pin  128  is pushed into the threaded body  131 . The pin  129  will maintain the stop pin in the stopping position by riding along the edge of the threaded body  131 . However, it may be preferable to provide a short channel  134  on the threaded body  131 , where the pin  129  can lock into, as shown in FIG. 29 a . The spring  130  will ensure that the pin  129  is kept at the end of the respective channel. 
     In addition, each adjustable stop  88   c  includes a housing  136 . Each housing  136  is shown as an integral part of table assembly  14  but it is within the scope of the present invention to manufacture individual housings  136  and secure them to table assembly  14  if desired. Each housing  136  defines a threaded through bore  135  into which the threaded body  131  is threadably received. The stop pin  128  provides a surface for stop rod  84  to contact when the bevel angle of housing  32  is located at about 0° or about ±45° from the 0° bevel angle as is shown in the preferred embodiment. 
     The adjustability of each stop  88   c  is provided by the threaded connection between the threaded body  131  and housing  98  and this adjustability allows the operator to accurately set these specific bevel angles. An operator need only to lock the stop pin  128  in either channel, and lodge a wrench into cavity  133  to adjust the bevel angles. 
     When the bevel angle needs to be changed, handle  54  is rotated to release housing  32  from table assembly  14  and stop pin  128  is rotated so that pin  129  leaves the channel  134  and slides along channel  132 . Stop pin  128  is pulled out until the pin  129  hits the end of channel  132 . The stop rod  84  thus does not contact stop pin  128  or housing  98  when housing  32  is pivoted on shaft  40 . If the operator wants to return the stop pin  128  into the stopping position, the operator needs only to push and rotate the stop pin  128  so that pin  129  lodges itself within channel  134 . 
     The table assembly  14  may further be provided with a ramp  150 . The ramp  150  contacts the stop rod  84  when the miter saw is beveled in a clockwise direction M; i.e., from the −45° bevel angle towards the +45° bevel angle, so that the stop rod  84  retracts and bypasses the 0° bolt. 
     Persons skilled in the art will recognize that the present embodiment may be implemented with the override button  86  illustrated in FIGS. 6 and 7, instead of plaque  117 . This would allow the operator to withdraw the stop rod  84  to bypass the adjustable stops  88   c  and/or to disable the adjustable stops  88   c.  Furthermore, if the override button  86  is used, the adjustable stops  88   c  may be replaced with the adjustable stops  88   a.    
     Persons skilled in the art will also recognize that spring  130  need not be disposed between stop pin  128  and threaded body  131 . Instead, the spring  130  may be disposed between the stop pin  128  and the table  14 . 
     Persons skilled in the art may also recognize that the stop rod  84  may be fixed or may even be a casting in the housing  32  which extends into the table  14 . 
     Referring to FIGS. 31 through 33, a tenth embodiment of positive stop system  72  comprises a biasing spring  82 , a stop rod  84  and a stop system, preferably one of the stop systems shown in FIGS. 8 through 10. Biasing spring  82  is inserted into a stepped aperture  90  extending through the housing  32  such that it abuts the step formed within aperture  90 . Stop rod  84  is then inserted through spring  82  and through aperture  90 . 
     The housing  32  has a plaque  117 , which may be built separate to or integrated with the housing  32 . Spring  82  is trapped between plaque  117  and the stop rod  84 . A reduced diameter portion  92  of rod  84  extends through housing  32  and is inserted through a slot in plaque  117 . 
     An override rod  138  is provided through the housing  32 . The axis of the override rod  138  is preferably substantially perpendicular to the axis of the stop rod  84 . As shown in FIG. 33, the override rod  138  is provided with a rack  140  of teeth, which engage a pinion section  139  of the stop rod  84 . 
     Further, stop rod  84  has a helical groove  116  disposed on its body, that engages a stop  115  in housing  32 . Accordingly, linear movement of the override rod  138 , for example, along direction X, will cause the rotation of stop rod  84 . Because of the engagement between the stop  115  and the rod groove  116 , stop rod  84  moves axially while rotating, as in a screwing action, within housing  32  between a stop position and a release position with spring  82  biasing stop rod  84  into its stopped position. 
     Persons skilled in the art will recognize that the spring  82  shown in FIGS. 31 and 32 is a compression spring. Additionally, such persons will recognize that the same function, i.e., biasing stop rod  84  into its stopped position, can be achieved by rotational springs disposed on the stop rod  84 , or linear springs which bias the override rod  138  in the direction opposite to direction X, which force the rod  84  to rotate. Further, persons skilled in the art will recognize that other means, such as elastomeric materials and structures, can be utilized to bias the stop rod  84  into its stopped position. 
     Referring to FIGS. 34 through 36, an eleventh embodiment of positive stop system  72  comprises a biasing spring  82 , a stop rod  84  and a stop system, preferably one of the stop systems shown in FIGS. 8 through 10. Biasing spring  82  is inserted into a stepped aperture  90  extending through the housing  32  such that it abuts the step formed within aperture  90 . Stop rod  84  is then inserted through spring  82  and through aperture  90 . 
     The housing  32  has a plaque  117 , which may be built separate to or integrated with the housing  32 . Spring  82  is trapped between plaque  117  and the stop rod  84 . A reduced diameter portion  92  of rod  84  extends through housing  32  and is inserted through a slot in plaque  117 . 
     An override lever  141  is provided through the housing  32 . The rotational axis of the override lever  141  is preferably substantially perpendicular to the axis of the stop rod  84 . As shown in FIG. 36, the override lever  141  is provided with a pinion section  143 , which engages a rack  142  of teeth disposed on the stop rod  84 . 
     Accordingly, because of the engagement of the rack  142  and pinion  143 , rotational movement of the override lever  138 , for example, along direction W, is converted into linear movement of stop rod  84 . Thus, stop rod  84  moves axially within housing  32  between a stop position and a release position with spring  82  biasing stop rod  84  into its stopped position. 
     Persons skilled in the art will recognize that the spring  82  shown in FIGS. 34 and 35 is a compression spring. Additionally, such persons will recognize that the same function, i.e., biasing stop rod  84  into its stopped position, can be achieved by rotational springs disposed on the stop rod  84  and/or on the override lever  141 . Further, persons skilled in the art will recognize that other means, such as elastomeric materials and structures, can be utilized to bias the stop rod  84  into its stopped position. 
     The above detailed description describes different embodiments of the present invention. Persons skilled in the art may recognize other alternatives to the means disclosed herein, such as using non-adjustable fixed castings instead of the adjustable stops  88   a , or placing the adjustable stops  88   a  on the housing  32 , while placing the stop rod  84 , and/or the means to retract the rod, on the table  14 . Similarly, persons skilled in the art will recognize that a knob can be placed on the stop rod  84  to manually withdraw it from the stopping position. However, all these additions and/or alterations are considered to be equivalents of the present invention.

Technology Classification (CPC): 1