Patent Abstract:
This specification discloses a mechanism that alters the cutting angle of a motorized miter saw. The cutting angle is altered by a mechanism that deploys a member from underneath the cutting material resting surface to above the cutting material resting surface. When deployed above the cutting material resting surface, the angle between the blade and cutting material is altered.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Not Applicable 
     FEDERALLY SPONSORED RESEARCH 
     Not Applicable 
     SEQUENCE LISTING OR PROGRAM 
     Not Applicable 
     BACKGROUND OF THE INVENTION 
     Field of Invention 
     This invention relates to power saws; specifically, power saws capable of making miter angle adjustments. 
     When trimming windows, doorways, and the like, there are typically two vertical pieces of trim boards, a horizontal trim board at the top, and for widows a couple of boards for the sill. Consider where the vertical pieces intersect the horizontal piece. At the intersection, each of the boards would have to be cut at a 45 degree angle. Professional carpenters want the boards to meet in such a manner that the vertical and horizontal boards look almost like one piece. This can be achieved by raising the board off of the miter saw base by a small amount when making the 45 degree cut. Typically, a professional carpenter would put a portion of a pencil or other similar item under the board to raise it slightly when making the 45 degree cut. Therefore, when the boards are put in place, this results in the horizontal board and vertical board contacting on an edge instead of complete contact on the adjoining surfaces. The edge is the edge that is visible when looking at the window framing. Because of this edge type contact, the boards look as if they are almost one board. 
     Miter saws have an adjustment that can produce the same type cut without using a pencil or similar item as an offset; however the adjustment is time consuming. On most miter saws, one would have to reach behind the saw and rotate a knob, tilt the saw head, and tighten the knob. For a professional carpenter, the time to do this is prohibitive. One saw manufacturer makes a saw which allows the adjustment to be made from the front of the saw. Even so, making the adjustment is time consuming. Additionally, because of the mass of the saw motor, making the adjustment quickly is awkward. Once the adjustment was made, it would be easy to not notice it, which would result in incorrect cuts when making trimming cuts other than the one described above, or worse yet when making framing cuts. 
     Objects and Advantages 
     This invention remedies the previously mentioned problems by providing a power saw with a miter angle adjustment specifically designed for trimming applications. The power saw with miter angle adjustment has the following advantages:
         a) Makes an adjustment in the miter angle such that trimming pieces will adjoin on an edge.   b) Provides a way to make the adjustment very quickly.   c) Provides a way to remove the adjustment very quickly.   d) Makes it clear whether the adjustment is or is not in place.       

     SUMMARY 
     In accordance with the present invention, a power saw with a miter angle adjustment. 
    
    
     
       DRAWINGS 
       Figures 
         FIG. 1  shows an isometric view of a miter saw with the offset that produces the miter angle adjustment. 
         FIG. 2  shows an isometric view of a table saw with the offset that produces the miter angle adjustment. 
         FIG. 3  shows an isometric view of a skill saw with the offset that produces the miter angle adjustment. 
         FIG. 4  shows an isometric view of a jig saw with the offset that produces the miter angle adjustment. 
         FIG. 5  shows an isometric view of a rack and pinion system that positions the offset. 
         FIG. 6  shows an isometric view of a bar sliding in a channel that positions the offset. 
         FIG. 7  shows a section view of the bar that slides in a channel. 
         FIG. 8  shows an isometric view of a bar that rotates into a channel to position the offset. 
         FIG. 9  shows a section view of the bar that rotates into a channel. 
         FIG. 10  shows a front view of a bar that rotates from underneath to position the offset. 
         FIG. 11  shows a left side view of a bar that rotates from underneath. 
         FIG. 12  shows a front view of a four bar mechanism that positions the offset where the mechanism is positioned via a thread rod. 
         FIG. 13  shows a front view of a four bar mechanism that positions the offset where the mechanism is positioned via a latch. 
         FIG. 14  shows a section view of a four bar mechanism that positions the offset where the mechanism is positioned via a latch. 
         FIG. 15  shows a 2 dimensional view of a rectangular-shaped rotating bar that positions the offset. 
         FIG. 16  shows the first section view of a rectangular-shaped rotating bar that positions the offset. 
         FIG. 17  shows the left side view of a rectangular-shaped rotating bar that positions the offset. 
         FIG. 18  shows a 2 dimensional view of a triangular-shaped rotating bar that positions the offset. 
         FIG. 19  shows the first section view of a triangular-shaped rotating bar that positions the offset. 
         FIG. 20  shows the left side view of a triangular-shaped rotating bar that positions the offset. 
         FIG. 21  shows a 2 dimensional view of a circular-shaped rotating bar that positions the offset. 
         FIG. 22  shows the first section view of a circular-shaped rotating bar that positions the offset. 
         FIG. 23  shows the left side view of a circular-shaped rotating bar that positions the offset. 
         FIG. 24  shows a 2 dimensional view of an oval-shaped rotating bar that positions the offset. 
         FIG. 25  shows the first section of an oval-shaped rotating bar that positions the offset. 
         FIG. 26  shows the left side view of an oval-shaped rotating bar that positions the offset. 
         FIG. 27  shows a 2 dimensional view of an attachment that repositions the offset. 
         FIG. 28  shows the left side view of an attachment that repositions the offset. 
     
    
    
     Reference Numerals 
     
         
           10  power saw 
           20  power saw motor 
           30  power saw blade 
           40  cutting material resting surface 
           50  offset 
           60  saw embodiment with rack and pinion offset positioning 
           70  rack 
           80  pinion 
           90  rack and pinion supporting structure 
           100  bracket 
           110  shaft 
           120  handle 
           130  sliding bar 
           140  channel for sliding bar 
           150  rotating bar 
           160  hinge 
           170  rotating bar channel 
           180  offset defining structure 
           190  hinge 
           200  spring 
           210  first positioning surface 
           220  second positioning surface 
           230  bar  1  of the four bar mechanism 
           240  bar  2  of the four bar mechanism 
           250  bar  3  of the four bar mechanism 
           260  bar  4  of the four bar mechanism 
           270  rotational joint 
           280  rotational joint with a threaded receptor 
           290  threaded rod 
           300  universal joint 
           310  structure positioning handle 
           320  handle 
           330  spring 
           340  restraining link 
           350  structure positioning latch 
           360  latch 
           365  latch keyhole 
           370  structure defining offset 
           380  shaft 
           390  shaft bearings 
           400  shaft restrainer 
           410  handle 
           420  spring 
           430  horizontal restraining member 
           440  vertical structural member 
           450  hinge 
           460  rectangular portion of shaft 
           470 —Offset prior to adding attachment that extends the offset 
           480 —Attachment for extending offset 
           490 —Screw 
       
    
     DETAILED DESCRIPTION 
     FIGS.  1 - 4 —Preferred Embodiment 
     This invention, at a minimum, applies to four types of saws as illustrated in the Figures listed below:
         Miter Saw:  FIG. 1     Table Saw:  FIG. 2     Skill Saw:  FIG. 3     Jig Saw:  FIG. 4         

     In  FIGS. 1  thru  4  the saw  10  has a motor  20 , a cutting blade  30 , a cutting material resting surface  40 , and an offset  50 , wherein the offset changes the cutting angle between the cutting blade  30  and the cutting material (not shown). 
     A preferred embodiment of the saw of the present invention is illustrated in  FIG. 5  wherein the offset  50  is positioned via a rack  70  and a pinion  80 . The pinion  80  is connected to a shaft  110  that is positioned by a bracket  100  that is connected to the supporting structure  90 . The shaft  110  is connected to the handle  120  where rotation of the handle  120  rotates the shaft  110  which rotates the pinion  80  which moves the offset  50  relative to the cutting material resting surface  40 . This results in the offset  50  moving from a position below the cutting material resting surface  40  to a plurality of positions above the cutting material resting surface  40 . 
     FIGS.  6 - 7 —Alternate Embodiment 
     An alternate embodiment of the saw of the present invention is illustrated in  FIG. 6  (isometric view) and  FIG. 7  (section view), where the offset  50  is defined via a sliding bar  130  that slides in a channel  140 . Referring to  FIG. 7 , notice that the bar  130  is held captive in the channel  140  due to the bar  130  and the channel  140  being wider at the innermost portions. The bar  130  can slide to a position that would engage the cutting material (not shown) to a position that would be clear of the cutting material. 
     FIGS.  8 - 9 —Alternate Embodiment 
     An alternate embodiment of the saw of the present invention is illustrated in  FIG. 8  (isometric view) and  FIG. 9  (section view), where the offset  50  is defined via a rotating bar  150  that rotates about a hinge  160  from a position in the channel  170  to a position (as represented by the dashed lines) clear of the cutting material resting surface  40  and thus clear of the cutting material (not shown). Referring to  FIG. 9 , notice that the bar  150  can rotate into the channel  170  because the channel  170  and the bar  150  are shaped such that the bar  150  is not held captive by the channel  170 . 
     FIGS.  10 - 11 —Alternate Embodiment 
     An alternate embodiment of the saw of the present invention is illustrated in  FIG. 10  (isometric view) and  FIG. 11  (left view), where the offset  50  is defined via an offset defining structure  180  that rotates about a hinge  190  constrained either by the first positioning surface  210  or by the second positioning surface  220 , wherein the spring  200  holds the offset defining structure  180  on the positioning surfaces ( 210 ,  220 ). When the offset defining structure  180  is positioned via the first positioning surface  210 , then the offset  50  would engage the cutting material (not shown). When the offset defining structure  180  is positioned via the second positioning surface  220 , then the offset  50  would not engage the cutting material. 
     FIG.  12 —Alternate Embodiment 
     An alternate embodiment of the saw of the present invention is illustrated in  FIG. 12  (two dimensional view), where the offset  50  is positioned via a four bar mechanism. The first bar  230  is defined by the structure of the saw  10 , bar two  240  is connected on one end to bar one  230  and on the other end to bar three  250 , the other end of bar three  250  is connected to bar four  260 , and the other end of bar four  260  is connected to bar one  230 . The bars are connected via three rotational joints  270  and one rotational joint with a threaded receptor  280 . When the handle  320  is rotated, the universal joint  300  rotates, which rotates the threaded rod  290  which interfaces with the rotational joint with a threaded receptor  280 . This rotation results in the positioning of the four bar mechanism such that the offset  50  is positioned at a plurality of positions below the cutting material resting surface  40  to a plurality of positions above the cutting material resting surface  40 . 
     FIGS.  13 - 14 —Alternate Embodiment 
     An alternate embodiment of the saw of the present invention is illustrated in  FIG. 13  (two dimensional view) and  FIG. 14  (section view), where the offset  50  is positioned via a four bar mechanism. The first bar  230  is defined by the structure of the saw  10 , bar two  240  is connected on one end to bar  230  and on the other end to bar three  250 , the other end of bar three  250  is connected to bar four  260 , and the other end of bar four  260  is connected to bar one  230 . The bars are connected via four rotational joints  270 . The four bar mechanism is positioned via a latch  360  that is connected to a connecting link  340  that is attached to the four bar mechanism. When the latch  360  is rotated one way it slides through a key hole  370  in the structure  350  positioning the latch  360 . The latch  360  is restrained via a spring  330 . Depending on the engagement of the latch, the four bar mechanism is positioned such that the offset  50  is either above the cutting material resting surface  40  or below the cutting material resting surface  40 . 
     FIGS.  15 - 17 —Alternate Embodiment 
     An alternate embodiment of the saw of the present invention is illustrated in  FIG. 15  (two dimensional view),  FIG. 16  (section view) and  FIG. 17  (left side view), where the offset  50  is positioned via a structural member  370  that is attached to the shaft  380  that is held in place via bearings  390  such that when the shaft  380  is rotated to one position, the offset  50  is above the cutting material resting surface  40  and when the shaft  380  is rotated to another position, the offset  50  is below the cutting material resting surface  40 . The shaft  380  would be held in position via the horizontal restraining member  430  interfacing with the rectangular portion  460  of the shaft  390 . The horizontal restraining member  430  pivots about the hinge  450  that is attached to the vertical structural member  440 . The spring  420  forces the horizontal restraining member  430  against the rectangular portion  460  of the shaft  390  which fixes the shaft  390  in place. 
     Operation— FIGS. 5-17   
     The operation of the saw of the present invention entails moving the offset  50  from a position below the cutting material resting surface  40  to a position above the cutting material resting surface  40  and vice versa via the mechanisms depicted in  FIGS. 5-17 . The positioning of the offset affects the miter cutting angle. A carpenter might make several cuts where the change in the miter angle is needed, and then reposition the offset  50  such that no change in miter angle would occur. 
     ADVANTAGES 
     Based on the description above, the advantages of the saw of the present invention follow: 
     The power saw with miter angle adjustment has the following advantages:
         a) This invention provides a way for a carpenter to quickly make a small miter angle change and to quickly remove the miter angle change. The change in miter angle is very precise (i.e. the same change every time).   b) This invention makes it very clear that the miter angle adjustment is or is not in place.   c) This invention greatly improves the ability of a professional carpenter to make consistent high quality cuts where the adjoining boards contact on edge.   d) This invention does not impede in any way the normal use of the saw when the miter angle adjustment is not in place.       

     CONCLUSION, RAMIFICATIONS, AND SCOPE 
     This invention provides a saw that allows small adjustments in miter angles to be made quickly and precisely. Additionally, this invention makes it very clear whether the adjustment is or is not in place. 
     Although the description above contains many specifics, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. For example, there are many ways to hold a four bar mechanism in place, most if not all of which would be applicable to this invention. Additionally, there are many ways to constrain a shaft that rotates as well as many ways to configure and implement a rack and pinion system. In general, there are many ways to position an offset that would be applicable to this invention. The important characterizing feature is that the offset is positioned.

Technology Classification (CPC): 8