Abstract:
A power tool having an integrated control system includes a workpiece supporting surface, a cutting instrument extendable above the workpiece supporting surface, a guard assembly securable above the workpiece supporting surface for covering at least a portion of the cutting instrument, the guard assembly having a first state for providing a first level of protection and a second state for providing a second level of protection, a motor coupled with the cutting instrument, and a power switch operable for starting the motor for driving the cutting instrument. The power tool includes a control system in communication with the guard assembly for determining if the guard assembly is in the first state or the second state. Before the motor is started, the control system automatically disables the motor if it determines that the guard assembly is in the second state. The control system includes a bypass switch for enabling starting of the motor when the guard assembly is in the second state.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit of commonly assigned U.S. Provisional Application No. 61/101,182, filed Sep. 30, 2008, the disclosure of which is hereby incorporated by reference herein. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention generally relates to power saws, and more specifically relates to table saws having integrated control systems. 
         [0004]    2. Description of the Related Art 
         [0005]    Table saws typically include a base or frame that supports a table having a planar top surface. The table generally includes a slot through which a cutting member, such as a circular saw blade, protrudes above the top surface of the table. Most table saws have a splitter that is mounted in alignment with a trailing end of the saw blade. When cutting a workpiece, the splitter maintains the two portions of the workpiece that have been cut spaced from one another to reduce the possibility of workpiece kickback. Many conventional table saws also include top guards and side guards that protect the operator from injury caused by accidental contact with a rotating saw blade. In some instances, the splitter, the top guards, and/or the side guards may be removed to make certain types of cuts, such as non-through cuts. 
         [0006]    There have been many efforts seeking to encourage operators to leave guarding in place or to place guarding back on table saws after specific projects requiring their temporary removal have been completed. For example, in one embodiment, commonly assigned U.S. Patent Application Publication No. 2007/0163408, the disclosure of which is hereby incorporated by reference herein, discloses a table saw guard that enables the guard to be removed and reattached without the use of tools. The table saw guard includes a riving knife and guard assembly that provides a clear view of the work zone, blade and work piece, and is easily adjustable to accommodate different size workpieces and cutting angles. In one embodiment, the riving knife extends upwardly from the table and is substantially coplanar with the saw blade, and the guard assembly is releaseably attached to an upper end of the riving knife using a rotatable latch. 
         [0007]    In some instances, it may be advisable to automatically shut down a table saw if the guard has been removed. In one embodiment, commonly assigned U.S. Pat. No. 6,418,829, the disclosure of which is hereby incorporated by reference herein, teaches a control device for a power tool including a protective guard provided over a cutting blade that prevents the use of the power tool when the protective guard is not in place. The control device includes a proximity detector that detects a distance between the guard and a table top, and an interlock system that prevents operation of the power tool when a distance less than a predetermined relative proximity is not detected. A pair of magnets is secured to the guard and a pair of reed switches is mounted beneath the table top. The reed switches are closed when the guard is in place. The interlock system allows the saw to be started when the reed switches are both closed and prevents start up when the reed switches are open. When the guard is not present the saw motor may be started using a key-activated bypass circuit. 
         [0008]    In spite of the above advances, there remains a need for mechanical guard assemblies for table saws that protect users from accidentally contacting rotating saw blades during operation, while providing users with a sufficient viewing area of the cutting zone between the workpiece and the saw blade. There also remains a need for guard assemblies that are easily removable and reinstallable so that users will be more likely to reinstall the guarding after it has been removed for performing specific cuts, rather than continuing to operate the table saw without the guard. In addition, there remains a need for table saws having integrated control systems that inform an operator of the guard status of the saw, that require a bypass operation to be performed before using the table saw without guarding in place, and that prevent an operator from tampering with the system to overcome the control system. Moreover, there remains a need for table saws having integrated control systems that are may not be easily overridden, bypassed, or fooled by an operator. 
       SUMMARY OF THE INVENTION 
       [0009]    In one embodiment, a power tool such as a table saw desirably has an integrated control system that may include a workpiece supporting surface, a cutting instrument extendable above the workpiece supporting surface, and a guard assembly securable above the workpiece supporting surface for covering at least a portion of the cutting instrument. The guard assembly preferably includes a first state for providing a first level of protection and a second state for providing a second level of protection. The power tool preferably includes a motor coupled with the cutting instrument, a power switch operable for starting the motor for driving the cutting instrument, and a control system in communication with the guard assembly for determining if the guard assembly is in the first state or the second state. In one embodiment, before the motor is started, the control system desirably automatically disables the motor if it determines that the guard assembly is in the second state. The control system may include a bypass switch operable for bypassing the control system and starting then motor when the guard assembly is in the second state. 
         [0010]    In one embodiment, the power switch preferably has a first indicator light that is illuminated when the motor is running and that is de-activated when the motor is disabled or shut down. In one embodiment, the first indicator light may be illuminated when the operator approaches the table saw to provide an indication of the guard status of the saw. Thus, the first indicator light may be illuminated before the motor is started and remain illuminated after the motor is started to provide a continuous indication of the guard status of the saw. In one embodiment, the power switch is preferably pulled in a first direction for supplying power to the motor and may be pushed in a second opposite direction for stopping the supply of power to the motor. The power switch may also be a push on-push off switch, or any other switching mechanism well-known to those skilled in the art. In one embodiment, the bypass switch is desirably rotatable for bypassing the control system. 
         [0011]    In one embodiment, the bypass switch desirably includes a second indicator light that is continuously illuminated when the control system determines that the guard assembly is in the second state. The second indicator light preferably blinks after the bypass switch is activated. The second indicator light preferably continues to blink after the bypass switch has been activated and while the motor is running. The bypass switch is desirably a momentary switch that may not be held in the activated position for permanently bypassing the control system. In one embodiment, a table saw having an integrated control system has only an indicator light that indicates that the guard assembly is in the second state. This particular embodiment may not have an indicator light that indicates that all of the guarding is present and that the guard assembly is in the first state. 
         [0012]    In one embodiment, the control system preferably includes a time-out feature associated with the bypass switch, which requires the power switch to be moved into the ON position for starting the motor within a predetermined time period after activating the bypass switch. The predetermined time period is desirably between 1-30 seconds in length. In one embodiment, the predetermined time period is preferably about 10 seconds in length. In one embodiment, the integrated control system is adapted to determine whether there has been a state change in the bypass switch, whether the state of the bypass switch was just changed, or whether the bypass switch is being held in an open position or a closed position. In one embodiment, the integrated control system will not allow activation of the motor if it determines that the bypass switch is being permanently held in the open or closed position. 
         [0013]    In one embodiment, a power tool having an integrated control system may include a workpiece supporting surface, a cutting instrument extendable above the workpiece supporting surface, a guard assembly securable above the workpiece supporting surface for covering at least a portion of the cutting instrument, the guard assembly having a first state for providing a higher level of protection and a second state for providing a lower level of protection, a motor coupled with the cutting instrument for driving the cutting instrument, and a power switch moveable in a first direction for starting the motor for driving the cutting instrument. The power tool desirably includes a control system in communication with the guard assembly for determining if the guard assembly is in the first state or the second state, whereby the control system disables the motor if an operator attempts to start the motor with the guard assembly in the second state. The control system preferably includes a bypass switch for bypassing the control system to enable starting the motor with the guard assembly in the second state. 
         [0014]    The bypass switch is preferably a momentary bypass switch and the control system includes a time-out feature that requires the power switch to be pulled within a predetermined time period after activating the momentary bypass switch. The bypass switch is desirably moveable in a second direction, such as a rotating operation, that is different than the first direction for the power switch. 
         [0015]    In one embodiment, the power switch preferably includes a first indicator light for indicating if the motor is running, and the bypass switch includes a second indicator light for indicating if the guard assembly is in the first state or the second state. In one embodiment, the second indicator light is desirably continuously illuminated if the guard assembly is in the second state and the motor is not running, and the second indicator light blinks after the bypass switch has been activated and while the motor is running. 
         [0016]    In one embodiment, the power tool is preferably a table saw and the guard assembly includes a splitter and a top guard assembly securable atop the splitter. The control system desirably includes a first sensor assembly associated with the splitter for determining whether the splitter is in the first state or the second state, and a second sensor assembly associated with the top guard assembly for determining whether the top guard assembly is secured atop the splitter. 
         [0017]    In one embodiment, a table saw having an integrated control system desirably includes a table having a top surface, a cutting blade extendable above the top surface of the table, and a guard assembly coupled with the table for covering at least a portion of the cutting blade. The guard assembly preferably has a first state for providing a higher level of protection and a second state providing a lower level of protection. The table saw desirably includes a motor coupled with the cutting blade, a power switch moveable in a first direction for starting the motor so as to drive the cutting blade, and a control system in communication with the guard assembly for determining if the guard assembly is in the first state or the second state. In one embodiment, the control system may automatically disable the motor if the motor has not yet been started and when the guard assembly is in the first state, and the control system preferably includes a bypass switch having an indicator light for providing an indication of whether the guard assembly is in the first state or the second state. 
         [0018]    In one embodiment, the bypass switch is preferably moveable in a second direction that is different than the first direction of the power switch for bypassing the control system and starting the motor for operating the table saw when the guard assembly in the second state. In one embodiment, the bypass switch and the power switch may not be activated using the same or a simultaneous hand motion. In one embodiment, the power switch is desirably pulled for starting the motor and pushed for stopping the motor, and the bypass switch is preferably rotated for bypassing the control system and running the motor when the guard assembly is in the second state. The power switch may also be a push on-push off power switch, or have any other activation mechanism well known to those skilled in the art. 
         [0019]    In one embodiment, a table saw having an integrated control system may include a table having a top surface, a cutting blade extendable above the top surface of the table, a motor coupled with the cutting blade, a power switch moveable in a first direction for starting the motor for driving the cutting blade, and a guard assembly covering at least a portion of the cutting blade, the guard assembly having a first state for providing a higher level of protection and a second state for providing a lower level of protection. The table saw desirably includes a control system in communication with the guard assembly for determining if the guard assembly is in the first state or the second state. The control system is preferably designed to prevent the motor from starting if it determines that the guard assembly is in the first state, and the control system desirably includes a bypass switch that is operable for bypassing the control system and starting the motor with the guard assembly in the second state. 
         [0020]    In one embodiment, the guard assembly preferably includes a splitter, an anti kickback pawl, and a top guard assembly secureable atop the splitter. The top guard assembly preferably includes a top guard and one or more side guards pivotally secured to the top guard. 
         [0021]    The integrated control system may include a first sensor assembly in communication with the splitter for determining if the splitter is fully installed in an upright position, rotated into a low riving knife position, or decoupled from the table. The integrated control system preferably includes a second sensor assembly in communication with the top guard assembly for determining if the top guard assembly is secured atop the splitter. The integrated control system may include a third sensor for determining the presence of an anti kickback pawl. The integrated control system may include a fourth sensor for determining the rotational status of the one or more side guards. 
         [0022]    In one embodiment, the guard assembly is in the first state when the splitter is in the fully installed upright position and the top guard assembly is secured atop the splitter. In one embodiment, the guard assembly is in the second state when the top guard assembly is not secured atop the splitter. In one embodiment, the control system desirably includes a time-out bypass switch. In one embodiment, if the bypass switch is activated, the operator preferably has a pre-determined period of time for pulling the power ON switch. If the power ON switch is not pulled within the pre-determined period of time (e.g. 10 seconds), the operator must desirably activate the bypass switch once again before the power may be turned for the system. 
         [0023]    In one embodiment, the control system of the present invention preferably provides a clear indication to an operator of the guarding status of the power tool as the operator approaches the tool. If any of the guarding is not present or in the proper position, one or more indicator lights will desirably illuminate to provide an indication of the guard status of the power tool to the operator. 
         [0024]    In one embodiment, the control system of the present invention desirably provides an affirmative indication to an operator of the guard status of a power tool. In one embodiment, this is preferably accomplished by providing one or more illuminating lights observable by an operator. In one embodiment, a bypass switch preferably includes an indicator light that is continuously illuminated to alert an operator that some action must be taken before operating the power tool. Once the bypass switch has been activated, the indicator light may blink to alert the operator that the saw may now be operated with the guarding removed. 
         [0025]    In one embodiment, the control system of the present invention preferably includes a first array of sensors associated with the top guard assembly including the top guard removable from the splitter and the side guard pivoted to the top guard. The system desirably includes a second array of sensors associated with the splitter to determine if the splitter is in the high splitter position or in the low riving knife position. The array of sensors associated with the splitter preferably detects the position of the splitter/riving knife and requires appropriate action by an operator. If the splitter is in the high splitter position, and the top guard is in place, the operator may activate the system without using the bypass switch. If the splitter is in the low riving knife position, the operator is preferably required to use the bypass switch before beginning power to the motor. 
         [0026]    In one embodiment, the array of sensors associated with the splitter desirably prevents tampering by requiring the splitter to be fully inserted before beginning operation of the motor. In one embodiment, if an operator attempts to bypass the control system by taping over the sensors or inserting a dummy splitter against the sensors, the sensors will preferably detect that the splitter is not fully inserted and will not allow operation of the motor until the bypass switch is activated. 
         [0027]    These and other preferred embodiments of the present invention will be described in more detail below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]      FIG. 1  shows a perspective view of a table saw including a cutting blade and a splitter, in accordance with one embodiment of the present invention. 
           [0029]      FIG. 2  shows a fragmentary side view of the cutting blade and the splitter of  FIG. 1 . 
           [0030]      FIG. 3  shows the table saw of  FIG. 1  and a guard assembly securable atop the splitter. 
           [0031]      FIG. 4  shows the guard assembly of  FIG. 3  secured atop the splitter for covering the cutting blade. 
           [0032]      FIG. 5  shows the table saw of  FIG. 1  with the splitter rotated downwardly and into a low riving knife position. 
           [0033]      FIG. 6A  shows an exploded view of a splitter, in accordance with one embodiment of the present invention. 
           [0034]      FIG. 6B  shows the splitter of  FIG. 6A  after assembly. 
           [0035]      FIG. 6C  shows a top view of the splitter of  FIG. 6B  along line  6 C- 6 C. 
           [0036]      FIGS. 7A-7C  show a splitter and an array of sensors adapted for communicating with the splitter, in accordance with one embodiment of the present invention. 
           [0037]      FIG. 8  shows a method of attempting to override the integrated control system of the present invention. 
           [0038]      FIG. 9  shows a schematic view of a circuit for integrating a guard assembly into a table saw, in accordance with one embodiment of the present invention. 
           [0039]      FIG. 10  shows a perspective view of a table saw having an integrated guard system, in accordance with one embodiment of the present invention. 
           [0040]      FIG. 11  shows the table saw of  FIG. 10  after a guard assembly has been removed. 
           [0041]      FIG. 12  shows the table saw of  FIG. 11  after a bypass switch has been activated for operating the table saw with at least one of the components of the guard assembly removed. 
           [0042]      FIG. 13  shows a table saw having an integrated guard system, in accordance with one embodiment of the present invention. 
           [0043]      FIG. 14  shows a front view of an indicator panel for an integrated control system, in accordance with one embodiment of the present invention. 
           [0044]      FIG. 15  shows a flow chart for operation of a control system integrated into a table saw in accordance with one embodiment of the present invention. 
           [0045]      FIG. 16  shows a front perspective view of a table saw having an integrated control system, in accordance with one embodiment of the present invention. 
           [0046]      FIGS. 17A-17D  show an indicator panel for the table saw shown in  FIG. 16 . 
           [0047]      FIG. 18  shows a perspective side view of a table saw having an guard assembly including a splitter, an anti kickback pawl, a top guard, and a side guard, in accordance with one embodiment of the present invention. 
           [0048]      FIGS. 19A-19G  show an indicator panel for an integrated control system, in accordance with one embodiment of the present invention. 
           [0049]      FIGS. 20A-20C  show an indicator panel for an integrated control system, in accordance with one embodiment of the present invention. 
           [0050]      FIGS. 21A-21C  show an indicator panel for an integrated control system, in accordance with one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0051]    Referring to  FIG. 1 , in one embodiment, a table saw  20  preferably includes a table  22  with a top surface  24  adapted to support a workpiece during a cutting operation. The table  22  desirably includes an aperture  26  that extends through the table  22  and a rotatable saw blade  28  that projects through the aperture for cutting a workpiece. The saw blade  28  is preferably coupled with a motor (not shown) and a carriage  30  that are preferably located below the table  22   
         [0052]    The table saw  20  preferably includes a splitter  32  that extends through the aperture  26  and projects upwardly from the top surface  24  of the table  22 . In one embodiment, the splitter  32  is preferably formed from a flat plate that extends through the aperture  26  in the table  22 . A lower end of the splitter  32  may be mounted to the carriage  30  of the table saw  20  so that it is aligned with the saw blade  28 . In one embodiment, the splitter  32  is desirably mounted on the carriage  30  for movement in conjunction with the saw blade  28 . 
         [0053]    In one embodiment, as a workpiece is cut by the saw blade  28 , the splitter  32  desirably maintains the cut portions of the workpiece (not shown) spaced from one another as the remainder of the workpiece is fed through the saw blade  28 , and prevents the stock that may bind between the blade and the fence from getting caught by the teeth on the back of the blade. As is well known to those skilled in the art, keeping the cut portions of the workpiece separated helps to prevent potential binding of the workpiece with the saw blade  28  during a cutting operation, which minimizes the possibility of kick back of the workpiece. 
         [0054]    Referring to  FIG. 2 , the splitter  32  preferably has a leading edge  34  that defines a concave surface having a radius that is slightly larger than the radius of the saw blade  28  and is preferably spaced from and conforms to the outer edge  36  of the saw blade  28 . In one embodiment, the spacing between the leading edge  34  of the splitter  32  and the saw blade  28  may range from about 3 mm (0.12 inches) to 8 mm (0.31 inches). The concave shape of the leading edge  34  of the splitter  32  preferably enables the splitter to substantially surround the rear portion  36  of the saw blade  38  while the saw blade is rotating to provide protection for the user against accidental contact between the user and the saw blade. 
         [0055]    Referring to  FIG. 2 , in one embodiment, the splitter  32  may include the leading edge  34 , a trailing edge  38 , an upper end  40 , and a lower end  42 . The upper end  40  preferably includes a first anchor point  44  adjacent the leading end of the splitter  32  and a second anchor point  46  adjacent the trailing end  38  of the splitter. The first anchor  44  preferably includes a hook that projects rearward from the top edge  40  of the splitter  32 . The second anchor  46  preferably includes a hook that projects downwardly from the trailing edge  38  of the splitter. The first and second anchors  44 ,  46  preferably project in directions that prevent the top guard from inadvertently moving toward the saw blade  38 . The upper end  40  also desirably includes a stabilizing flange  48  projecting therefrom. The lower end  42  of the splitter  32  is preferably adapted to be secured to the support carriage  30  ( FIG. 1 ) located below the top surface of the table. 
         [0056]    Referring to  FIG. 3 , in one embodiment, the table saw  20  desirably includes a guard assembly  52  that is attachable to the splitter  32  to prevent an operator from contacting the saw blade  28  during a cutting operation. The guard assembly  52  may include a top guard  54  attachable to the upper end  40  of the splitter  32 . The top guard  54  desirably has a first finger  56  and a second finger  58  that each extends forward from the point of contact between the top guard  54  and the splitter  32 . The two fingers  56 ,  58  are adapted to extend beyond a leading edge  60  of the saw blade  28  to prevent an operator from contacting the saw blade  28 . The two fingers  56 ,  58  are preferably spaced from each other to form a gap  62  therebetween that provides an unobstructed view of the saw blade  28  and workpieces being cut by the saw blade  28 . The gap  62  between the fingers  56 ,  58  may also provide the operator with a view of alignment markings (not shown) on the workpiece to allow the user to precisely cut the workpiece using the saw blade  28 . 
         [0057]    In one embodiment, the fingers  56 ,  58  preferably have interior chamfered edges extending along a portion of their length. The chamfered edges desirably increase the view of the cutting zone. 
         [0058]    The guard assembly  52  also preferably includes a latch  64  that is pivotally attached to the top guard  54  for securing the guard assembly  52  to the splitter  32 . An underside of the top guard  54  preferably includes grooves (not shown) adapted to engage the first anchor point  44  and the stabilizing flange  48  for securing the top guard  54  atop the splitter  32 . After the top guard  54  has been positioned atop the splitter  32 , the latch  64  may be pivoted downwardly into a locking position for engaging the second anchor point  46  and locking the guard assembly  52  atop the splitter  32 . In one embodiment, the latch may be an over-center latch that is designed to project above or stand up over the top of the top guard  54  to provide a clear visual indication that the latch is not locked. 
         [0059]    The guard assembly  52  also preferably includes a side guard  66  that is pivotably mounted to the top guard  54 . The side guard  66  desirably provides a protective surface that surrounds the front and the sides of the exposed portion of the saw blade  28 . The side guard  66  preferably has a left arm  68  and a right arm  70 , each extending beyond the fingers  56 ,  58  of the top guard  54 . The left and right arms  68 ,  70  desirably provide protection from the saw blade  28 . Likewise, each of the left and right arms  68 ,  70  desirably has a front portion  72 A,  72 B that may contact an operator&#39;s hands or fingers positioned on top of the workpiece as it is fed to be cut, thus providing a tactile warning that the operator&#39;s hands or fingers may be near the saw blade  28 . The left and right arms  68 ,  70  are preferably pivotally mounted to the top guard  54  and are adapted to pivot so as to not interfere with measuring, aligning, or cutting the workpiece. 
         [0060]    In one embodiment, the side guard  66  may include a sensing apparatus that provides an audible or visual signal if the user contacts the side guard  66  when the saw blade  28  is rotating. The audible signal may be a bell or an alarm. The visual signal may be a warning light. In one embodiment, the saw blade  28  may stop rotating when the user contacts the side guard  66 . This sensing mechanism may be activated based on a change in capacitance sensed by the side guard  66 , or by another type of sensing means that is well-known to those of ordinary skill in the art. 
         [0061]    Each of the left and right arms  68 ,  70  of the side guard  66  may be independently lifted and rotated relative to the top surface  24  of the table  22  and the top guard  54 . The top guard  54  desirably remains stationary as the left and right arms  68 ,  70  of the side guard  66  are rotated and pivoted from their lowered positions. Providing a two-piece side guard having arms  68 ,  70  that move independently of one another preferably allows a further range of potential tilt of the saw blade  28  with respect to the top surface  24  of the table  22  without requiring the side guard  66  to be removed. Moreover, the side guard  66 , with independently moveable arms  68 ,  70 , may be used with a workpiece that does not have a flat surface or that is not parallel to the top surface  24 . As a result, an operator may be less likely to remove the side guard  66  before commencing a cutting operation. Additionally, the side guard  66  desirably provides additional protection to the user because a greater area on the side and front surfaces of the saw blade  28  may be enclosed by the side guard during angled cuts (or when cutting workpieces with angled surfaces). In addition, a greater area around the saw blade is preferably covered than would be available with a side guard having arms that are attached together on either side of the saw blade. 
         [0062]      FIG. 4  shows the table saw  20  after the guard assembly  52  has been secured atop the splitter  32 . In  FIG. 4 , the latch  64  is in the locked position for locking the guard assembly  52  in place atop the splitter  32 . With the guard assembly  52  locked in place, the top guard  54  includes the first finger  56  and the second finger  58  that each extend above the saw blade  28 . The first and second fingers  56 ,  58  preferably extend forward from the splitter  32  to cover the top and front of the saw blade  28 . The fingers  56 ,  58  are desirably separated from each other by a gap  62  that allows the user to view the rotating saw blade  28  and feeding of the workpiece against the leading cutting edge  60  of the saw blade  28 . 
         [0063]    As noted above, the bottom surface (not shown) of the top guard  54  preferably includes one or more grooves, adapted to receive the anchors and the stabilizing flange projecting from the upper end when the top guard  54  is secured atop the riving knife  32 . 
         [0064]    In order to make certain cuts in workpieces, it may be necessary to remove the guard assembly and move the splitter  32  into a low riving knife position shown in  FIG. 5 . In one embodiment, movement of the splitter may involve rotational and/or translational motion. In one embodiment, it may be necessary to remove the guard assembly and rotate the splitter  32  into a low riving knife position when making a cut in which the top of the cutting blade  28  does not protrude from the top surface of the workpiece. For certain cuts, it may be necessary to completely remove the splitter  32 . After these cuts have been made, operators are advised to reinstall the splitter and the guard assembly to the configuration shown in  FIG. 4 . Unfortunately, this is not done in all instances because there is little performance incentive to do so. Operating with all of the guarding components in place as shown in  FIG. 4  is preferred. 
         [0065]    In one embodiment, a table saw has a guard control system integrated therein that preferably temporarily shuts down the saw from further operation or that preferably requires activation of a bypass switch prior to starting the motor if any of the guarding components (e.g. the riving knife and/or the guard assembly) are missing, or if the guarding components are adjusted into a compromised position. The control system may include one or more sensors for detecting if any of the guarding components are missing or if any of the guarding components are not properly assembled atop the cutting saw. The sensing may be accomplished in various ways including radio frequency identification, magnetic sensing, capacitive sensing, mechanical switches, or electrical contacts. In one embodiment, the control system desirably includes an electrical circuit having a resistive value method that prevents tampering with the circuit. 
         [0066]    Referring to  FIGS. 6A and 6B , in one embodiment, a table saw preferably has a control system including one or more sensing components integrated into the splitter  32 . Referring to  FIG. 6A , in one embodiment, the splitter  32  preferably includes a first plate  74 A and a second plate  74 B. The first and second plates  74 A,  74 B preferably have the same shape and dimensions. The plates,  74 A,  74 B may be made of metal or other well-known, durable materials. The splitter  32  desirably includes a conductive element  76  that is adapted to be laminated between the first and second plates  74 A,  74 B. The conductive element  76  desirably includes an upper end  78  having a male connector  80  projecting therefrom and a lower end  82  having a female connector  84  formed therein. The conductive element  76  is preferably positioned between the first and second plates  74 A,  74 B for providing a signal transmission path between the upper ends  40  and the lower ends  42  of the respective first and second plates  74 A,  74 B. 
         [0067]      FIG. 6B  shows the first and second plates  74 A,  74 B assembled together with the conductive element  76  disposed between the plates. The male end connector  80  is preferably accessible at the upper end  40  of the splitter  32  and the female connector  84  is preferably accessible at the lower end  42  of the splitter  32 . 
         [0068]    Referring to  FIGS. 6B and 6C , in one embodiment, the upper end of the male connector  80  is preferably accessible between the first and second plates  74 A,  74 B. The upper-most end of the male connector  80  is preferably slightly recessed within the splitter  32  so that it remains protected below the top surface  40  of the splitter when the top guard is removed and the upper end of the riving knife is exposed. In one embodiment, the electrical connection below the table surface is preferably a male connector that engages the female connector  84  at the lower end of the conductive element  76 . Providing a male connector below the table surface that is adapted to receive a female connector at the lower end of the splitter minimizes the likelihood of saw dust contamination or the packing of dust about the connector parts. 
         [0069]    In one embodiment, the first and second plates  74 A,  74 B may be secured together such as by being glued together. In other embodiments, the first and second plates  74 A,  74 B may be assembled together using alternative methods such as riveting, welding, or integrating simple appendage and socket pairs across the respective plates  74 A,  74 B that structurally interlock with one another. In one embodiment, the splitter  32  is preferably a single plate having a channel formed between upper and lower ends thereof that is adapted to accommodate a conductive element therein for transmitting signals through the splitter. 
         [0070]    In one embodiment, a table saw may include two distinct splitter assemblies that may be secured to the saw. The first splitter is desirably used during normal cuts and includes all of the guarding components shown and described above in  FIGS. 3 and 4 . In one embodiment, the top guard is permanently connected to the upper end of the splitter. The second splitter is preferably adapted to be used for shallow cuts and does not include the guard assembly including the top guard  54  and the side guard  66 . When making cuts using the second splitter, a bypass operation is desirably required before the cutting blade will rotate. In one embodiment, the first splitter desirably has no electrical connections or sensors for determining if the top guard is in place because the top guard is permanently secured to the splitter. The first splitter preferably has a key or sensors that enable the integrated control system to determine whether the first splitter is installed. In one embodiment, the second splitter may be used as a riving knife and has a unique key that is different than the first splitter so that the integrated control system may determine when the second splitter is installed and recognize the difference between the first splitter and the second splitter. Although this embodiment having two splitters is not limited by any particular theory of operation, it is believed that this particular embodiment eliminates the need for a user-connectable electrical connection at the top of the splitter. 
         [0071]    Referring to  FIG. 7A , in one embodiment, the splitter  32  preferably has an aperture  86  formed therein. The lower end  42  of the splitter  32  is adapted to be secured in a carriage located below the table (not shown). In one embodiment, the carriage desirably includes a first sensor  92 , a second sensor  94  and a third sensor  96 . In one embodiment, when the splitter  32  is not fully installed in the carriage ( FIG. 7A ), the three sensors  92 ,  94 ,  97  are preferably open and the control system will recognize that the splitter is not installed. Referring to  FIG. 7B , when the splitter  32  is properly seated in the carriage, the first sensor  92  and the third sensor  96  are closed. In addition, the aperture  86  is aligned with the second sensor  92  so that the second sensor  94  remains open. When the control system recognizes the first sensor  92  is closed, that the second sensor  94  is open and that the third sensor  96  is closed, the control system preferably recognizes that the splitter  32  is properly installed in the carriage  30 . If the control system recognizes that the splitter is not fully installed as shown in  FIG. 7A , the control system desirably recognizes that all of the guarding components are not completely installed and may prevent starting of the motor and/or shut down the table saw until bypass occurs. 
         [0072]    In one embodiment, when the splitter  32  is moved into the low riving knife position shown in  FIG. 7C , the aperture  86  is aligned with the third sensor  96  so that the first sensor  92  and the second sensor  94  are closed, and the third sensor  96  is open. In the position shown in  FIG. 7C , the control system will desirably indicate that all of the guarding is not present and the table saw may only be started using the bypass protocols described herein. 
         [0073]    Referring to  FIG. 8 , in one embodiment, the control system preferably incorporates an anti-tamper design that may not be permanently bypassed by inserting a dummy splitter in the carriage. As shown in  FIG. 8 , if a dummy splitter  132  is inserted to rig the control system, all of the sensors  92 ,  94 ,  96  will be in the closed position and the system will recognize that the splitter  32  ( FIG. 7B ) is not properly installed. 
         [0074]    Referring to  FIG. 9 , in one embodiment, a control system  100  is preferably interconnected with the riving knife  32  and the guard assembly  52  including the top guard  54  and the side guard  66 . The control system  100  desirably forms a control circuit that determines if the riving knife  32  and the guard assembly  52  are properly assembled over the saw blade  28 . If the guard assembly  52  or the riving knife  32  are not in place or properly secured atop the table saw, or if the side guard  66  is elevated before starting the table saw, the control system will desirably recognize the deficiency and generate appropriate response signals as will be described in more detail below. 
         [0075]    Referring to  FIG. 9 , in one embodiment, the side guard  66  preferably has at least one sensor  110  provided therein and the table  22  has a sensor  102  provided therein. The sensors may be contact sensors. When the side guard  66  is lowered, the sensor  110  in the side guard  66  is desirably read by the sensor  112  in the table  22  to indicate that the side guard is in a lowered position. If the side guard  66  is in an elevated position when the operator attempts to start the table saw, the sensor  112  will preferably detect that the sensor  110  has been lifted and the motor will not start unless a bypass protocol is followed. In one embodiment, the sensors may be provided between the side guard and the top guard to determine the rotational angle of the side guard. The control system may use information such as the tilt angle of the saw blade and the blade height of the saw blade when determining whether the rotational angle of the side guard is acceptable for starting the motor or whether the bypass protocol must be followed before starting the motor. 
         [0076]      FIG. 10  shows one embodiment of the present invention in which a control system, such as one or more features of the control system shown and described in herein, is integrated into a table saw. Referring to  FIG. 10 , the table saw  20  preferably includes table  22  having a top surface  24  and a saw blade  28  projecting through an aperture  26  in the table  22 . In  FIG. 10 , the splitter  32  is preferably aligned with the trailing end of the saw blade  28  and the guard assembly  52  is secured atop the splitter  32 . The guard assembly  52  desirably includes the top guard  54  and the side guard  66  pivotally secured to the top guard  54 . 
         [0077]    The table saw  20  preferably includes a base  120  that supports the table  22  and that has various control elements provided thereon. In one embodiment, the table saw  20  desirably includes an ON/OFF power switch  122  that may be pulled up and away from the base  120  for turning the motor of the table saw ON, and that is preferably depressed for turning the motor of the table saw OFF. The table saw  20  preferably includes a first indicator light  124  that is desirably illuminated when all of the guarding components have been properly assembled over the saw blade  28 . In one embodiment, the first indicator light  124  is green. When the splitter  32  and the guard assembly  52  including the top guard  54  and the side guard  66  have been properly assembled over the cutting blade, the control system preferably recognizes that all of the guarding components are property installed. In response, the first indicator light  124  may be illuminated and the motor of the table saw may be started for rotating the cutting blade. 
         [0078]    The table saw  20  also desirably includes a bypass switch  126  that is rotatable in a clockwise direction for bypassing the control system and operating the table saw when one or more of the guarding components are removed or not properly installed. The bypass switch  94  may include a second indicator light  128  that may be activated to illuminate continuous light or a blinking light. In one embodiment, the second indicator light  128  is yellow. 
         [0079]    The control system desirably includes one or more control programs or routines stored therein. The control system may include a central processing unit having one or more microprocessors or analog controls and one or more memory devices for storing the programs/routines, analyzing information about the guard status of the system, providing an indication of the guard status to an operator, and operating the table saw. In one embodiment, the table saw  20  is plugged into an outlet so that power is provided to the table saw. All of the guarding components of the assembly including the riving knife  32 , the top guard  54  and the side guard  66  are in place. The power switch  122  is in the OFF position and the motor for the table saw is supplied with power and ready for activation. In this configuration, the first indicator light  124  is illuminated and the second indicator light  128  is not illuminated. In a next step, the operator pulls on the power switch  122  to start the motor and rotate the saw blade  28 . Because all of the guards are properly assembled and in place, the motor rotates the saw blade  28  as the first indicator light  124  remains illuminated and the second indicator light  128  is not illuminated. During operation, the left and right arms  68 ,  70  of the side guard  66  may be pivoted up and away from the top surface  24  of the table  22  as the work piece is pushed through the cutting blade  28 . During this cutting operation, the first indicator light  124  remains illuminated and the second indicator light  128  remains darkened. After the workpiece has been completely cut, the operator pushes the power switch  122  to the OFF position so that the motor stops and the cutting blade  28  stops rotating. 
         [0080]    Referring  FIG. 11 , if the guard assembly  52  ( FIG. 10 ) is removed so that only the splitter  32  remains in place, the control system will desirably recognize that guarding has been removed and will de-activate the first indicator light  124  and illuminate the second indicator light  128 . In one embodiment, the second indicator light  128  may blink once to draw the operator&#39;s attention before remaining continuously illuminated. The continuous illumination of the second indicator light  128  preferably provides the operator with an indication that one or more of the guarding components are not in place. This feature may be useful in instances where an operator approaches the table saw for the first time and seeks to determine why the saw motor will not start. At this stage, the operator cannot start the motor and rotate the cutting blade  28  by simply pulling the power switch  122  to the ON position. Before the motor will start, the operator must rotate the bypass switch  126  to the position shown in  FIG. 12 . Once the bypass knob  126  has been rotated to the position shown in  FIG. 12 , the second indicator light  128  will blink, while the first indicator light  124  is not illuminated. After the bypass switch has been activated, the operator is required to pull the power switch  122  to the ON position for starting the motor and rotating the cutting blade  28 . In one embodiment, upon activating the bypass switch  126 , a timer preferably limits the time between rotating the bypass switch  126  and pulling the power switch  122  to the ON position for starting the motor. If the motor is not started within the predetermined time period (e.g. 10 seconds), the second indicator light  128  on the bypass switch will desirably remain illuminated and the operator will be required to reactivate the bypass switch  126  once again before the saw may be started. Once again, the operator may be required to pull the power switch  122  within the predetermined time period of rotation the bypass switch. In one embodiment, the bypass switch  126  is a momentary switch that may not be permanently held in the bypass position. 
         [0081]    After the bypass switch  126  has been rotated in a clockwise direction as shown in  FIG. 12 , the operator may pull the power switch  122  for turning the motor ON. In this condition, the first indicator light  124  is preferably de-activated and the second indicator light  128  blinks. The blinking light preferably reminds the operator and others in the vicinity of the table saw  20  that one or more components of the guard assembly are missing, disabled, or not properly assembled over the cutting blade  28 . In one embodiment, the second indicator light desirably remains blinking as the saw is operated. In one embodiment, the second indicator light remains continuously illuminated as the saw is operated. At the end of a cutting operation, the operator may push the power switch  122  into the OFF position to stop the motor and the rotation of the cutting blade  28 . At this stage, the first indicator light  124  desirably remains de-activated and the second indicator light  128  changes from blinking to remaining illuminated at all times. 
         [0082]    In one embodiment, the control system is desirably programmed to ensure that the activation of the bypass switch  126  cannot be performed simultaneously with starting the motor. This may be achieved by spacing the power switch  122  from the bypass switch  126  beyond the reach of a normal human hand. In one embodiment, this is preferably achieved by requiring a motion for the bypass switch that may not be done in concert with the motion required for pulling the power switch  122  to the ON position. In one embodiment, this requires the bypass switch  126  to be rotated and the power switch  122  to be pulled into the ON position. In one embodiment, the bypass switch  122  and the power ON switch  122  are both placed on the same side of the base  120  and within reach of an operator&#39;s hand so that the operator&#39;s other hand may support a workpiece. 
         [0083]    Referring to  FIG. 13 , in one embodiment, a third indicator light  140  may be placed atop the top guard  54  of the guard assembly  52  to provide an additional indicator that all of the guarding components are properly in place. The third indicator light  140  may be used to communicate to an operator that all of the guarding components are present and properly installed. In one embodiment, the third indicator light is green. Placing an indicator light on the guard assembly  52  to provide an indication that all of the guarding components are not in place would not be possible because the top guard  54  would not be present. 
         [0084]    In one embodiment, the indicator lights mentioned above preferably help an operator to determine what steps are required and whether the guarding components are in place. In one embodiment, one or more of the indicator lights may be back lit or may be located next to the operating switches. In one embodiment, the operating switches and the indicator lights are preferably located on the front face of a support or frame for the table saw. When an operator is making a cut, however, the operator is typically paying attention to the blade area of the cutting blade  28  and is not able to look at the front face  142  of the body  120 . Thus, the third indicator light  140  ( FIG. 13 ) may be useful for communicating that all of the guarding is present during a cutting operation. 
         [0085]    In one embodiment, one or more indicator lights may be provided atop the table. The indicators lights may be recessed so as to not interrupt the top surface of the table and/or interfere with the movement of workpieces positioned atop the table. 
         [0086]    Although the present invention is not limited by any particular theory of operation, it is believed that the control system disclosed herein will increase the usage of guarding components by reminding an operator of the current status of his or her guard assembly. This feature may be particularly useful in instances where an operator approaches a table saw for the first time and seeks to determine the guard status of the table saw and/or to determine why the table saw is not operating. Moreover, an operator will have an incentive to reinstall all of the guarding components atop the table saw so as to limit the extra steps required for using the bypass switch to bypass the automatic shutdown of the table saw  20 . 
         [0087]    In one embodiment, the control system preferably includes a first sensor that senses if a splitter is properly installed atop the table saw. If the splitter has been removed or has been rotated into a low riving knife position, one or more sensors will detect that full guarding is not in place. In one embodiment, the one or more sensors desirably includes an array of three sensors that are in communication with the splitter. In one embodiment, if the splitter is rotated to a lowered or less than optimal guarding position, the array of three sensors will preferably detect the rotated condition and the status of the guard assembly and the information will be transmitted to the system controller. 
         [0088]    In one embodiment, a second sensor assembly desirably detects the presence of the top guard and the side guards atop the table. If attempts are made to begin operating the power saw with the side guards spaced from the top surface of the table, the second sensor will desirably detect the spacing and transmit the information to the system controller. The system controller will preferably prevent the system from operating until the side guards are returned to the completely down position. In one embodiment, the system controller will desirably allow continued operation of the table saw if the side guards are elevated after the table saw is started. 
         [0089]    In one embodiment, if one or more of the guard assembly components are not in place when the operator attempts to activate the power switch, the second indicator light on the bypass switch will desirably blink once and then remain illuminated. In order to bypass the shut down, the bypass switch must preferably be activated or rotated. After the bypass switch has been activated, the second indicator light preferably blinks and the power switch may be activated or pulled to the ON position for operating the saw. The second indicator light preferably remains ON as long as the saw is operated. In one embodiment, once the power switch is returned to the OFF position, the saw may only be re-activated by once again rotating the bypass switch and pulling the power switch within a pre-determined time period. 
         [0090]    In one embodiment, the control system preferably includes a time out interlock coupled with the bypass switch. After activating the bypass switch, if the power switch is not pulled to the ON position within a predetermined period of time (e.g. 10 seconds) of rotating the bypass switch, then power may not go to the motor for rotating the saw blade and the bypass switch must be rotated once again. 
         [0091]    In one embodiment, the splitter preferably has an array of sensors in communication therewith that are used to indicate if the guard is removed, fully installed, or partly installed with the table. The splitter must desirably be fully installed into the table to operate the saw without performing the bypass operation disclosed herein. If the three sensors do not detect full installation of the splitter, the system will not operate. In one embodiment, sensor array desirably includes three sensors that form a unique combination of a closed, open and closed configuration that must be detected before operating the power saw without using the bypass mode. If the splitter is rotated into a low riving knife position, the closed, open, closed sensor array will not detect proper positioning of the splitter and the bypass mode must be activated. In other embodiments, other combinations of sensors may be used to detect whether the sensor is properly installed. 
         [0092]    In one embodiment, the side guards may be lifted away from the table after the table saw has been activated. If the side guards are lifted after activation and during rotation of the cutting blade, then the control system will allow the cutting blade to continue rotation. If the side guards are lifted before the blade is initially rotated, then the system will preferably not operate the motor until the bypass switch is activated, and the power switch is pulled after activating the bypass switch. 
         [0093]    In one embodiment, if the cutting blade is rotating and the splitter is removed during a cutting operation, the control system will preferably automatically shut down the motor and the saw blade will stop rotating. 
         [0094]    In one embodiment, a front panel observable by an operator desirably includes a series of lights that may be illuminated. Each light is preferably associated with one of the components of the guard assembly. In one embodiment, a first light on the front panel is desirably associated with the splitter, a second light on the front panel is desirably associated with the top guard, and a third light on the front panel is desirably associated with the side guards. In one embodiment, the front panel may include indicator lights for showing if an anti kick back pawl is installed. If any one of the components is not in place, the lights on the front panel will preferably show which guard parts are properly installed and which guard parts are not properly installed. 
         [0095]    In one embodiment, the bypass switch is preferably a momentary switch that may not be permanently held in the bypass mode position. After the bypass switch is activated, it must preferably be allowed to return to its normal position before the system may be operated. Thus, the bypass switch may not be pinned or held in the bypass state permanently, which prevents rigging the system to overcome the control system of the present invention. 
         [0096]      FIG. 14  shows a table saw having a control system including an indicator panel  180  provided on a front face of the table saw. The indicator panel  180  preferably includes a first bank of indicator lights  182  providing the status of the splitter, a second bank of indicator lights  184  providing information regarding the status of the top guard, and a third bank of indicator lights  186  providing the status of the side guard of the table saw. The first bank of indicator lights  182  desirably includes a first indicator light  182 A that illuminates when the splitter is fully installed and a second indicator light  182 B that illuminates when the splitter is not fully installed. The second bank of indicator lights  184  desirably includes a first indicator light  184 A that illuminates when the top guard is fully installed and a second indicator light  184 B that illuminates when the top guard is removed or not fully installed. The third bank of indicator lights  186  desirably includes a first indicator light  186 A that illuminates when the side guard is properly installed and a second indicator light  186 B that illuminates when the side guard is not properly installed or is spaced from the table prior to activating the motor. 
         [0097]    The indicator panel  180  also preferably includes an indicator light  188  that is illuminated to provide an indication that all of the guard components are property installed and in place over the saw blade. If all of the components are properly installed and in place, the indicator light  188  desirably illuminates. In one embodiment, the indicator light  188  is green. The indicator panel  180  also preferably includes an indicator light  190  that illuminates if one or more of the components of the guard assembly are not installed or property positioned over the saw blade. In one embodiment, the indicator light  190  is red or yellow and illuminates if one or more of the guarding components are not properly installed. 
         [0098]      FIG. 14  shows one preferred embodiment for providing an indication of whether all of the guarding components are in place. It is contemplated that other designs may be utilized and still fall within the scope of the present invention. For example, the indicator lights may replicate the shape of the guarding components. For example, a first bank of indicator lights may have the shape of a splitter, and a second bank of indicator lights may have the shape of a top guard of a guard assembly. A third bank of indicator lights may have the shape of the side guard. The parts may be illuminated a first color (e.g. green) when property installed and may be darkened or illuminated to a different color (e.g. red) when the particular guarding component is not properly installed. 
         [0099]    Referring to  FIG. 15 , in one embodiment, the central processing unit of the control system preferably includes one or more logic routines for operating the table saw. At the step designated  200 , the power saw is preferably plugged in to provide electrical power. At the step designated  202 , the system preferably determines if the splitter is in the high splitter position. If the sensors detect that the splitter is in the high position, an operator may pull the power switch to the ON position at the step designated  204  to run the motor (step designated  206 ). As the motor runs, the motor desirably rotates the cutting blade for cutting workpieces. At the step designated  208 , the operator may push the on/off switch for cutting power to the motor (step designated  210 ). 
         [0100]    If at the step designated  202 , the central processing unit desirably detects that the splitter is not in the high splitter position, the CPU next determines at the step designated  212  if the guard is in the low riving knife position. If the guard is in the low riving knife position, the bypass switch is desirably illuminated yellow at the step designated  214 . At the step designated  216 , the operator may rotate the bypass switch which starts a pre-set timer at the step designated  218 . The operator then preferably has a pre-determined time (step  220 ) to pull the power switch ( 204 ). After the operator turns the bypass switch at the step designated  216 , the indicator light blinks yellow at the step designated  222 . The operator may then complete the actions shown in steps  204 - 210 . If the pre-determined time period expires at step  220 , then no power is provided to the motor at step  224 . Thus, even if the operator pulls the power on/off switch at step  224 , no power will be provided to the motor at step  226 . 
         [0101]    The sensors used to determine if the splitter, the anti kickback pawl, the top guard, and the one or more side guards are in place may include any well known sensors used by those skilled in the art. These sensors may include Eddie current sensors, optical sensors, optical reflector sensors, rotobond position sensors, and contact micro switches. 
         [0102]    Referring to  FIG. 16 , in one embodiment, a table saw  320  having an integrated control system includes an indicator panel  380  located above a bypass switch  326 . The indicator panel preferably provides an indication of the status of the guarding on the table saw. As a result, an operator may be able to instantly determine the status of the guarding when approaching the table saw. Referring to  FIG. 17A , in one embodiment, the indicator panel  380  is adapted to be illuminated to show the various components of the guarding, namely the splitter  332 , the anti kickback pawl  335 , the top guard assembly  354 , and the one or more side guards  366 . Although  FIG. 17A  shows only four guard components, other embodiments may include additional guard components. In the embodiment shown in  FIG. 17A , all of the guard components are in place so that the splitter  332 , the anti kickback pawl  335 , the top guard  354 , and the one or more side guards  366  are illuminated. In one embodiment, the above-mentioned guard components are illuminated the color green. In other embodiments, other colors may be used to provide an indication of the status of the guard components. 
         [0103]    Referring to  FIG. 17B , in one embodiment, the one or more side guards  366  are illuminated the color red to indicate that the one or more side guards are not properly installed and/or that the one or more side guards are rotated upwardly before the motor is started. In  FIG. 17C , the top guard portion  354  of the indicator panel  380  is illuminated red to provide an indication that the top guard is not properly installed. In  FIG. 17D , the splitter portion  332  of the indicator panel  380  is illuminated red to indicate that the splitter is not properly installed or that the splitter has been rotated into a low riving knife position. 
         [0104]    Referring to  FIG. 18 , in one embodiment, a table saw  420  includes a cutting blade  428  that is protected by guarding including a splitter  432 , an anti kickback pawl  435 , a top guard assembly  454 , and one or more side guards  466 . The table saw preferably has an integrated control system that tracks the status of the guarding over the cutting blade  428 . In one embodiment, the table saw includes an indicator panel  480  having a first region  488  that provides an indication if all of the guarding components are properly installed, a second region  490  associated with the status of the one or more side guards  466 , a third region  492  associated with the status of the top guard  454 , a fourth region  494  associated with the status of the anti kickback pawl  435 , and a fifth region associated with the status of the splitter  432 . 
         [0105]    Referring to  FIG. 19B , in one embodiment, the splitter  432 , the anti kickback pawl  435 , the top guard  454 , and the one or more side guards  466  in the first region  488  of the indicator panel  480  are illuminated green when the guarding is properly installed. Referring to  FIG. 19C , in one embodiment, the one or more side guards  466  shown in the second region  490  of the indicator panel  480  are illuminated the color red if the one or more side guards are not properly installed or if the one or more side guards are rotated upwardly from the table top before the motor is started. Referring to  FIG. 19D , in one embodiment, the top guard  454  shown in the third region  492  of the indicator panel  480  is illuminated the color red if the top guard is not properly installed. Referring to  FIG. 19E , in one embodiment, the anti kickback pawl  435  shown in the fourth region  494  of the indicator panel  480  is illuminated red if the anti kickback pawl is not properly installed. Referring to  FIG. 19F , in one embodiment, the splitter  432  shown in the fifth region  496  of the indicator panel  480  is illuminated red if the splitter is not properly installed and/or if the splitter is rotated into the low riving knife position. 
         [0106]    Referring to  FIG. 19G , in one embodiment, the one or more side guards  466  in the second region  490 , the top guard  454  in the third region  492 , the anti kickback pawl  435  in the fourth region  494 , and the splitter  432  in the fifth region  496  are illuminated red if the particular guard component is not properly installed. The splitter  432  may be illuminated red if the splitter is rotated into the low riving knife position. The one or more side guards  466  may be illuminated red if one of the side guards is rotated upwardly from the table top prior to starting the motor. In other embodiments, other colors may be used for providing an indication as to the status of the guarding. 
         [0107]    Referring to  FIGS. 20A-20C , in one embodiment, an integrated control system for a table saw includes an indicator panel  580  that may be illuminated to indicate the status of the guarding. Referring to  FIGS. 20A and 20B , the indicator panel  580  preferably includes a first region  590  that shows the guard components and that is preferably illuminated green when the guard components are properly installed over the cutting blade. Referring to  FIGS. 20A and 20C , the indicator panel preferably includes a second region  592  that shows the guard components and that is illuminated red when the guard components are not properly installed over the cutting blade. In one embodiment, the individual components of the guard assembly may be illuminated green or red to show the status of the various components. Other colors may also be used to indicate the status of the guarding. 
         [0108]    Referring to  FIGS. 21A-21C , in one embodiment, an integrated control system for a table saw includes an indicator panel  680  that may be illuminated. Referring to  FIG. 21B , in one embodiment, the guard components illustrated on the indicator panel are illuminated green if all of the guard components are properly installed. Referring to  FIG. 21C , in one embodiment, the guard components illustrated on the indicator panel are illuminated red if one or more of the guard components are not properly installed. In the embodiment of  FIGS. 21A-21C , one or more of the guard components may be illuminated a first color (e.g. green) while one or more of the remaining guard components are illuminated a second color (e.g. red or yellow). Although the colors green, red, and yellow have been described, other colors may be used for indicating the status of the guarding. 
         [0109]    The headings used herein are for organizational purposes only and are not meant to limit the scope of the description or the claims. As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include”, “including”, and “includes” mean including but not limited to. To facilitate understanding, like reference numerals have been used, where possible, to designate like elements common to the figures. 
         [0110]    While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof.