Abstract:
A power tool includes a housing having a large diameter rear portion and a narrow diameter nosepiece. An end effector is rotatably coupled to the housing. A holder with a substantially annular holder body is received over the nosepiece and non-rotatably coupled to the housing. A substantially annular cover having at least one transparent surface, and an internal annular groove, is received at least partially inside the holder body, and non-rotatably and axially fixed with respect to the holder. A substantially annular printed circuit board is received at least partially inside the annular groove in the cover, and non-rotatably and axially fixed with respect to the cover. A plurality of lighting elements is operatively connected to the printed circuit board and radially disposed about the printed circuit board. The lighting elements are aligned with the at least one transparent surface so as to illuminate a workpiece.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 12/859,036, filed Aug. 18, 2010, titled “Power Tool with Light Emitting Assembly,” which is a continuation-in-part of U.S. patent application Ser. No. 12/379,585, filed Feb. 25, 2009, now U.S. Pat. No. 8,328,381, titled “Light For Power Tool and Method of Illuminating a Workpiece.” Each of these applications is incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present application relates generally to handheld power tools. More particularly, the present application relates to handheld power tools having a light configured to shine onto a workpiece machined by the power tool. 
       BACKGROUND 
       [0003]    This section provides background information related to the present disclosure which is not necessarily prior art. 
         [0004]    Power tools are often used in a variety of conditions ranging from well-lit indoor work spaces to outside construction sites or other areas that are not always well-lit. Accordingly, it is desirable to provide a method or apparatus that permits a power tool to have a lighting feature that will illuminate the workpiece that is being machined or worked on by the power tool. Such a lighting feature will assist a user to be able to adequately see the workpiece or work area that is being worked on or machined by the power tool even in substandard light conditions. 
         [0005]    Because power tools may be used in adverse environmental conditions, it is desirable to protect such a lighting feature from the adverse environmental conditions. 
       SUMMARY 
       [0006]    This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. In accordance with one embodiment of the present teachings, a power tool is provided. The power tool includes a housing, an end effector rotatable with respect to the housing, a collar non-rotatable with respect to the housing, a printed circuit board (PCB) fixed with respect to the housing a heat stake process, and a lighting element operatively connected to the PCB. The lighting element is adjacent to the end effector and in a recess of a transparent housing and located to illuminate a workpiece machined by the power tool. 
         [0007]    In accordance with another embodiment of the present teachings, a power tool is provided. The power tool includes a rotatable end effector, a non-rotatable collar, and a circular printed circuit board (PCB). Surface mount lighting elements are operatively connected to the PCB and are adjacent to the end effector to illuminate a workpiece machined by the power tool. The collar has a transparent cover supporting the PCB and wires configured to provide power to the PCB for illuminating the lighting elements. The lighting elements are annularly arranged on the PCB about the end effector. A portion of the end effector extends through a hole defined by the transparent cover and PCB. The transparent cover defines a groove and the PCB is coupled in the groove using a heat staking process. 
         [0008]    There has thus been outlined, rather broadly, certain embodiments of the invention in order that the detailed description thereof herein may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional embodiments of the invention that will be described below and which will form the subject matter of the claims appended hereto. 
         [0009]    In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of embodiments in addition to those described and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein, as well as the abstract, are for the purpose of description and should not be regarded as limiting. 
         [0010]    As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
         [0011]    Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]      FIG. 1  is a side view illustrating a power tool in accordance with an embodiment of the invention. 
           [0013]      FIG. 2  is a perspective view illustrating a front portion of a power tool in accordance with an embodiment of the invention. 
           [0014]      FIG. 3  is a perspective close-up view of the power tool of  FIG. 2  with the end effector removed in order to more distinctly show surrounding elements. 
           [0015]      FIG. 4  is a perspective view similar to that shown in  FIG. 3  with a retaining ring removed in order to more clearly show surrounding elements. 
           [0016]      FIG. 5  is a perspective view of a wire guide and printed circuit board (PCB) having light emitting diode (LED) elements. 
           [0017]      FIG. 6  is a partial perspective view of a bottom portion of the wire guide and PCB. 
           [0018]      FIG. 7  is a perspective view of the PCB and wires with the wire guide removed. 
           [0019]      FIG. 8  is a partial perspective rear view of the wire guide, PCB, and wires. 
           [0020]      FIG. 9  is a partial exploded perspective view of the wire guide and a power tool having some elements removed to better show other elements. 
           [0021]      FIG. 10  is a partial perspective view of a wire guide, clutch adjusting nut, clutch spring, and clutch washer mounted on the wire guide. 
           [0022]      FIG. 11  is a partial perspective view of a power tool and clutch collar where the clutch collar is shown in a forward position to illustrate the clutch adjusting nut, clutch spring, and clutch washer mounted to the nose cone. 
           [0023]      FIG. 12  is a partial rear perspective view of the wire guide mounted on the clutch collar. 
           [0024]      FIG. 13  is a partial perspective view of the wire guide mounted onto the nose cone. 
           [0025]      FIG. 14  is a partial cutaway perspective view of a nose cone as well as other elements mounted to the nose cone. The end effector and power transmission elements are removed for clarity. 
           [0026]      FIG. 15  is a partial perspective view of a power tool equipped with a holder in accordance with another embodiment of the invention. 
           [0027]      FIG. 16  is a partial perspective view with part of the housing removed of a power tool equipped with a holder similar to that shown in  FIG. 15 . 
           [0028]      FIG. 17  is a partial perspective view of a power tool with part of the housing removed to expose interior components. 
           [0029]      FIG. 18  is a partial perspective cut-away view of a power tool equipped with a holder similar to that shown in  FIG. 15 . The cut-away view illustrates some of the internal components of the power tool. 
           [0030]      FIG. 19  represents a cross-sectional view of a holder subassembly associated with the nosepiece shown in  FIG. 15 . 
           [0031]      FIG. 20  represents a perspective cross-sectional view of the holder subassembly shown in  FIG. 15 . 
           [0032]      FIG. 21  represents a perspective view of a transparent cover-circuit board in the embodiment of  FIG. 15 . 
           [0033]      FIG. 22  represents a perspective cross-sectional view of the transparent circuit board subassembly shown in  FIG. 21 . 
           [0034]      FIG. 23  represents a partial front perspective view of the subassembly shown in  FIG. 21 . 
           [0035]      FIG. 24  represents a close-up view of the circuit board/transparent housing interface of the subassembly shown in  FIG. 15 . 
           [0036]      FIG. 25  represents a rear perspective view of an alternate holder subassembly for use with the power tool shown in  FIG. 15 . 
           [0037]      FIG. 26  represents a perspective cross-sectional view of the holder subassembly shown in  FIG. 25 . 
           [0038]      FIG. 27  represents a front view of the holder subassembly shown in  FIGS. 25 and 26 . 
       
    
    
     DETAILED DESCRIPTION 
       [0039]    The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. Embodiments in accordance with the present invention provide a power tool having a light ring configured to shine light onto a workpiece being machined by the power tool. 
         [0040]    According to some embodiments of the invention, light emitting elements, such as light emitting diodes (LEDs), are placed in an annular or ring shape around part of the end effector and are configured to shine forward to illuminate the tool or accessory held by the end effector and the workpiece being machined by the tool. The end effector may be a tool or accessory holder mounted to an output spindle of the tool, as described in U.S. patent application Ser. No. 12/394,426, entitled “Bit Retention Device” filed on Feb. 27, 2009, the contents being incorporated herein by reference in its entirety. Other examples of end effectors that may be used in accordance with the invention may be the 7000 Series chuck manufactured and marketed by the Jacobs Chuck Manufacturing Company of Clemson, S.C. and quick change chucks similar to that which is found on products such as a DC825KA Impact Driver and a DC815KA Impact Driver that are manufactured and marketed by the DeWalt Industrial Tool Company of Baltimore, Md. 
         [0041]    While several different types of lighting elements can be used in accordance with the invention, such as light bulbs (for example, xenon bulbs) or other lighting elements, LED lights are discussed here as an example and do not limit embodiments in accordance with the invention to tools using LEDs. The LED lights, or other lighting elements, and associated parts are locked to the housing of the tool and do not rotate when the power tool is operated. The lights may be powered by the same power source that provides power to the power tool&#39;s motor. In the case of most cordless power tools, it is a battery that powers the power tool and in the case of corded tools it is AC current provided from source voltage through a cord. This AC current may be modified according to the needs of the lighting device being employed. In the case of LED lights, a rectifier may be employed to convert AC current to DC. 
         [0042]    A first embodiment in accordance with the present teachings is illustrated in  FIG. 1 . A power tool  50  has a housing  51  which can be of a clam shell type or any other suitable type housing. The power tool  50  may have a transmission housing  56  located at the front portion of the power tool  50  to encapsulate a portion of an end effector  53 . A handle  57  projects downwardly from the housing  51  and is terminated with a battery. The transmission housing of the embodiment of  FIG. 1   a  contains a speed reduction transmission (e.g., a single-stage planetary transmission) and an impact mechanism that provides an intermittent rotary impact to the end effector (e.g., a Pott mechanism). The transmission housing of the embodiment of  FIG. 1   b  contains a speed reduction transmission (e.g., a multi-stage planetary transmission) and at least a portion of a torque clutch that disengages when a predetermined torque is reached. The end effector  28  may be configured to hold an accessory or tool such as a drill bit or a driving type accessory such as a Philips or standard screwdriver. Other types of tools or accessories may be held and used in the end effector  28  as can appreciated by one skilled in the art. The movement of the end effector  28  may be controlled by the trigger  30 . The trigger  30  may selectively provide power from the battery  26  to the motor  32  located within the housing  22 . In some embodiments of the invention, the more the trigger or switch  30  is depressed the more power may be applied to the motor  32  which may cause the end effector  28  to spin faster. 
         [0043]    The power tool  20  may be equipped with a clutch collar  34 . Other embodiments in accordance with the invention may not have a rotating clutch collar, but rather a different rotating collar mechanism. The rotating collar mechanism may be a drill/hammer mode selector, a gear shifter, an on/off switch, a tool variable speed control or other rotating collar control mechanism. However, this specification will refer to a clutch collar as an example but does not limit embodiments in accordance with the invention to tools having clutch collars. The clutch collar  34  can provide protection for interior portions of the power tool  20 , particularly the transmission and other internal components of the power tool  20  that may be mounted on the nose cone  23 . The clutch collar  34  may be rotated to adjust the transmission. An example of a clutch and transmission that may work in accordance with the invention is shown in U.S. Pat. No. 7,066,691 which is incorporated by reference in its entirety. Of course, most any type of clutch and transmission may be used in accordance with the invention. Different angular positions of the clutch collar  34  may provide different amounts of torque and/or speed to the end effector  28  for a given trigger  30  position. A numbered scale  36  may appear on the clutch collar  34  in order to provide a user an indication of the setting of the clutch collar  34 . In some embodiments the user may turn the clutch collar  34  to a desired position by hand. A light ring  38  is located on a front portion of the power tool  20  just behind the end effector  28  in a recess  39  in the clutch collar  34 . 
         [0044]    In  FIG. 2 , a partial perspective view of a front portion of the power tool  20  is shown. An indicator  37  may be located on the nose cone  23 . The indicator  37  may provide a reference for the user for determining the angular position of the clutch collar  34  and a reference point for comparing the numbers on the numbered scale  36 . The light ring  38  is located within a recess  39  of the clutch collar  34 . The light ring  38  may include a lens cover  40 . The lens cover  40  may protect interior components of the tool from moisture or other contaminants. The lens cover  40  may include blisters  42  located on the lens cover  40  as to be directly over the LEDs  58  (as shown in  FIG. 5 ). The blisters  42  may be translucent or clear in order to permit light generated by the LEDs  58  to pass through. In some embodiments the blisters  42  may direct or focus the light. The blisters  42  may be round, rectangular, square or any other shape. In some embodiments the blisters  42  are shaped to correspond with the shape of the lighting elements  58 . In other embodiments the light may simply pass through the blisters  42 . The remainder of the lens cover  40  may be a dark color. Other color schemes may be used in accordance with the invention. 
         [0045]    The lens cover  40  is held axially in place from moving in a forward direction toward the end effector  28  by retaining ring  44 . The retaining ring  44  is mounted on a retainer  46  which is part of the nose cone  37  as better illustrated in  FIGS. 13 and 14  and described in more detail later below. 
         [0046]      FIG. 3  is a similar view to that shown in  FIG. 2 , however, the end effector  28  is removed to better illustrate certain features associated with the retaining ring  44  and the retainer  46 .  FIG. 3  shows portions  48  of the retaining ring  44  exposed in gap  50  that would fit within the groove  52  if it were not in the gap  50 . The retaining ring  44  fits within a groove  52  in the retainer  46 . When the retaining ring  44  is placed in the groove  52  the retaining ring  44  is secured in place. The retaining ring  44  prevents the lens cover  40  from axially moving forward toward the end effector  28 . 
         [0047]      FIG. 4  is a similar view as that shown in  FIG. 3 , however, the retaining ring  44  has been removed as well as the end effector  28  to better illustrate features of the lens cover  40  and the retainer  46 . The lens cover  40  includes tabs  56  which are located within the gaps  50  of the retainer  46 . The tab  56  and gap  50  combination keep the lens cover  40  aligned and from rotating around the retainer  46 . The groove  52  is also illustrated in  FIG. 4  in which the retaining ring  44  is located as shown in  FIG. 3 . 
         [0048]      FIG. 5  illustrates other aspects of the light ring  38  which are normally contained within the clutch collar  34  and located behind the lens cover  40 . As part of the light ring  38 , light emitting diodes or LEDs  58  are located at various points around the light ring  38 . In some embodiments in accordance with the invention, the LEDs  58  emit white light although in other embodiments the LEDs  58  might emit other colors of light. In some embodiments different LEDs on the same tool could emit different colors of light. While the embodiment shown in  FIG. 5  illustrates three LEDs  58  any number of LEDs may be used in accordance with the invention including one or more. 
         [0049]    The LEDs  58  are mounted to a ring-shaped printed circuit board or PCB  60 . The PCB  60  and LEDs  58  are fit into a trench  61  in the wire way  62 . The wire way  62  and trench  61  may allow for potting of the PCB if necessary. The wire way  62  provides protection and structural strength for the PCB so that undue mechanical loads are not placed upon the PCB  60 . Such support is desirable as a PCB  60  may be fragile and subject to breaking or malfunctioning. The wire way  62  may include snap-in features  64  which allow the PCB  60  to be pushed into the wire way  62  and then the snap-in features  64  snap out once the PCB  60  is located within the wire way  62 . The snap-in features  64  prevent the PCB  60  from coming out of the wire way  62 . 
         [0050]    The wire way  62  may include grooves  66 . Tabs  68  located on the PCB  62  may fit within the grooves  66  within the wire way  62 . The tabs  68  and grooves  66  combination help the PCB  60  and the wire way  62  be aligned and may prevent or resist the PCB  60  from rotating with respect to the wire way  62 . 
         [0051]    The wire way  62  may include a PCB holding portion  70  which is generally circular in shape and a wire supporting portion  72 . The wire supporting portion  72  may include a channel  74  which is sized and located to contain wires  76 . The wires  76  may provide power to the PCB  60  which in turns provides power to illuminate the LEDs  58 . The wire supporting portion  72  of the wire way  62  provides a structure for the wires  76  to be supported in and provides protection for the wires  76 . The wires  76  may terminate with a plug  78 . The plug  78  may fit into plug supporting structure  80  located within the wire supporting portion  72  so that the plug  78 , which is made of a more rigid material than the wires  76 , is held securely to the wire way  62  via the plug supporting structure  80 . In some embodiments, the plug  78  may be press fit into the wire supporting portion  72  of the wire way  62 . The circuit to which the PCB  60  is connected may also include an electromagnetic surge suppression circuit (such as a zener diode) for static and over-voltage protection. The circuit may also include a resistor or resistors to drop the voltage from the battery pack voltage to an appropriate level for the LEDs. 
         [0052]    Some embodiments do not have a separate PCB, wire guide, wires and connector. For example, plated plastics can be used whereby the wire guide could be first molded into a shape similar to the wire guide  62  as shown. Secondly, tracks (like on a standard PCB) could be created on this plastic piece, and could include all of the pads to mount LEDs and other components, the tracks, or “wires,” from the front of the tool back to the connector area, and could even include the male end of the connector. The components (diodes, resistors, etc.) could then be soldered to this one piece, and would be electrically connected back to the place where the wires would connect it to the switch. This would greatly simplify the assembly. 
         [0053]      FIG. 6  is a partial perspective view of a bottom portion of the wire way  62 . The wire way  62  may be equipped with a collar stopping tab  82  which will be explained in more detail below as  FIG. 12  is discussed. 
         [0054]      FIG. 7  is a perspective view similar to that shown in  FIG. 5 , however, the wire way  62  has been removed in order to better illustrate some of the features shown in  FIG. 7 . The LEDs  58  are mounted onto the PCB  60 . The PCB  60  shows the tabs  68 . While the embodiments shown in the figures show five tabs  68 , one skilled in the art can appreciate that other numbers of tabs or other features may be employed in order to help keep the PCB aligned and/or rotationally locked to the wire way  68 . 
         [0055]    The wires  76  are attached to a rear portion of the PCB  60 . The plug  78  includes the plug stopping structure  84  which butts against a portion of the wire way  68  to prevent the plug  78  from being inserted too far into the wire way  62 . 
         [0056]      FIG. 8  illustrates the plug stopping structure  84  located on the plug  78  butted against the wire supporting portion  72  of the wire way  62 . The wires  76  are located within the channel  74 . In some embodiments, the plug  78  snaps into the wire supporting portion  72  and the wires  76  may be pressed into the channel  74  in a press fit manner to secure the wires  76  into the channel  74 . A rear portion of the collar stopping tab  82  is also illustrated in  FIG. 8 . 
         [0057]      FIG. 9  illustrates the housing  22  and the wire way  62 . The nose cone  23  has been removed in order to better illustrate how the plug  78  attaches to a receiving plug  86 . The plug  78  is slid into the receiving plug  76 . The plug stopping structure  84  slides into slots  87  located on the receiving plug  86 . Once the plug  78  and the receiving plug  86  have been mated together, power from the wires  88  is communicated to the wire  76 . The joint made of the plug  78  and the receiving plug  86  provide a rigid support for the connection of the wires  76  and  88 . The wires  88  may receive power from the battery  26  as controlled by the trigger  30 . In some embodiments the wires  88  extend out of a switch body associated with the trigger  30 . In other embodiments, a switch body could have connectors to which the wires  88  are soldered or otherwise connected. The trigger switch may include electronics for variable speed control. The wires  88  may be soldered to a PCB located inside the switch body. 
         [0058]    In accordance with some embodiments of the invention, when the trigger  30 , as shown in  FIG. 1 , is depressed, power is sent to the wires  88  and in turn  76  to illuminate the LEDs. 
         [0059]      FIG. 10  is a partial perspective view of the guide  62  showing several additional elements on the guide  62 . A clutch adjusting nut  90  is butted against the guide  62 . The stop tab  82  is fit into a notch  92  in the clutch adjusting nut  90 . The notch  92  in the clutch adjusting nut  90  aligns to the stopping tab  82  on the guide  62  to assist in providing proper assembly of the threads between the adjusting nut  90  and the nose cone  23  during assembly. In some embodiments and as shown in  FIG. 10 , the notch  92  and the clutch adjusting nut  90  may have chamfered edges  96  to the notch walls  94 . The chamfered edges  96  may assist in the stopping tab  82  to be seated in the notch  92  and the clutch adjusting nut  90 . 
         [0060]    According to some embodiments, a combination of the notch  92  and the clutch adjusting nut  70  and the stopping tab  82  in combination with the other tabs and notch combinations  50 ,  56 ,  66 ,  68  can assure that the lens cover  40 , the nose cone  23 , the wire way  62 , the PCB  60 , and the clutch adjusting nut  90  are aligned with respect to each other. 
         [0061]    The clutch adjusting nut  90  includes a ridge  100 . As shown in  FIG. 10  a clutch spring  102  urges at one end against the ridge  100  and at the opposite end of the clutch spring  102 , the clutch spring  102  urges against a clutch washer  104 . The clutch spring  102  exerts a force on the ridge  100  of the clutch adjusting nut  90  which in turn urges the wire way  62  against the lens cover  40  and ultimately against the retaining ring  44 . The force exerted by the clutch spring  102  keeps the light ring assembly  38  in axial position. As shown in  FIG. 11  the clutch washer  104  urges against the nose cone  23 . 
         [0062]      FIG. 11  illustrates the clutch washer  104 , clutch spring  102 , and the clutch adjusting nut  90  mounted to the nose cone  23 . The clutch collar  34  is shown in a forward axial position and not yet installed on the power tool  20  in order to expose the clutch washer  104 , the clutch spring  102  and the clutch adjusting nut  90 . 
         [0063]    To provide ease in the assembly of the power tool  20 , a tab  98  on the clutch adjusting nut  90  is scored with marks or notches  106  on one of the adjustment tabs  98 . The scoring  106  provides a visual aid when assembling the collar  34  to properly align the clutch collar  34 . The adjustment tab  98  on the clutch adjusting nut  90  is aligned with a desired notch  108  in the clutch collar  34 . Once the desired notch  108  is aligned with the desired adjustment tab  98 , the clutch collar  34  can be fitted onto the power tool  20 . In some embodiments, the indicator  34  and the numbered scale  36  may also provide assistance in aligning the clutch collar  34  to provide proper assembly of the clutch collar  34  onto the nose cone  23 . 
         [0064]      FIG. 12  is a partial perspective view of the clutch collar  34  installed onto the guide  62 . Other elements have been omitted from  FIG. 12  in order to better show the interaction between the guide  62  and the clutch collar  34 . The clutch collar  34 , in some embodiments in accordance with the invention, is rotatable. The clutch collar  34  is rotatable on the power tool  20  in order to provide different torque and/or speed settings for the end effector  28 . It may be desirable to limit the rotation of the clutch collar  34  in both directions to establish a maximum setting for turning the clutch collar clockwise and a maximum setting when turning the clutch collar counterclockwise as shown in  FIG. 12 . Making maximum and minimum settings is, in some embodiments, accomplished by using the collar stopping tab  82  which butts against the stop  110  on the clutch collar  34 . The wall  112  on the stop  110  butts against a wall  114  on the collar stopping tab  82  to provide a limit to clutch collar  34  rotation in a clockwise direction as viewed in  FIG. 12 . The same stop  110  and collar stopping tab  82  provide a stop for rotating the clutch collar  34  in the opposite direction (i.e., counterclockwise as viewed in  FIG. 12 ). This is accomplished when the clutch collar  34  is rotated so that the opposite wall  116  on the stop  110  butts against the opposite wall  118  on the tab  82 . 
         [0065]      FIG. 12  also illustrates additional notches  108  in the clutch collar  34  for providing detents when the clutch collar  34  is rotated to various settings with respect to the nose cone  23 . 
         [0066]      FIG. 13  is a partial perspective view of the guide  62  mounted onto a stem portion  120  of the nose cone  23 . A lock portion  124  of the guide  62  fits into a groove  122  of the stem portion  120  of the nose cone  23 . The groove  122  is sized and dimensioned so that the lock portion  124  of the wire supporting portion  72  of the guide  62  fits within the groove  122  and locks the guide  62  to be angularly fixed with respect to the nose cone  23 . The locks  124  located on the wire supporting portion  72  of the guide  62  are wider than the rest of the wire supporting portion  72  and aid in permitting the guide  62  to be securely seated in the groove  122  of the stem portion  120  of the nose cone  23 . 
         [0067]    A second groove  126  is in the nose cone  23  for allowing the wire supporting portion  72  of the guide  62  to fit within the groove  126  of the nose cone  23 . The retainer  46  on the nose cone  23  and the groove  52  of the nose cone  23  are also shown forward of the guide  62 . The above described features also help align the guide  62  with respect to the nose cone  23 . 
         [0068]    According to some embodiments, the retainer  46  is integral with the stem  120  and the nose cone  23 . In other embodiments of the inventions, they may be separable parts. 
         [0069]      FIG. 14  is a partial cutaway perspective view of the nose cone  23  and additional parts described below.  FIG. 14  shows how the parts described herein are assembled together according to some embodiments of the invention. The transmission, spindle, and other parts associated with turning the end effector have been omitted to more clearly show the parts described herein. The retaining ring  44  is seated within the groove  52  of the retainer  46 . The retaining ring  44  provides a limit of forward axial movement of the lens cover  40 , the guide  62 , and the clutch adjusting nut  90 . The clutch spring  102  presses against the clutch washer  104  to urge the clutch adjusting nut  90  to urge the guide  62 , PCB  60 , and lens cover  40  against the retaining ring  44 . The wires  76  are located in a channel  74  defined by the guide  62  and the nose cone  23 . The wires  76  are protected from the spinning parts of the end effector mechanism. 
         [0070]    Although an example of the light ring  38  is shown on a power driver, it will be appreciated that the light ring  38  can be used on other rotary power tools such as impact drivers, drills, hammer drills, routers. 
         [0071]    Referring to  FIGS. 15-24 , in another embodiment, a light ring  138  is mounted on a different power tool  147  than shown in  FIGS. 1-14 . The power tool  147  is not equipped with a rotatable collar as described in the embodiments above. A holder  140  configured to be used with the power tool  147  holds the light ring  138 . The light ring  138  includes a generally circular PCB  160  similar to the PCB  60  described above. The PCB  160  and the holder  140  may include snap-in features similar to the snap-in features  64  described above, so that the PCB  160  snaps into and is secured in the holder  140 . 
         [0072]    A circular lens cover  162  may be mounted to the holder  140  in front of the PCB  160  similar to embodiments described above. The lens cover  162  may include snap-in elements that correspond with snap-in elements on the holder  140 . In other embodiments in accordance with the invention, the lens  40  may be secured in place with a retaining ring system similar to that described above. 
         [0073]    The holder  140  may attach to a transmission housing  123  of the power tool  147  with snap-in elements located on both the holder  140  and the transmission housing  123  similar to the snap-in features described in the embodiments above. In other embodiments in accordance with the invention, the light ring holder  140  may be secured in place in a variety of ways including, but not limited to, a retaining ring system similar to the embodiments described above. 
         [0074]    The holder  140  includes a housing portion  142 , a chin shroud  144 , and a wire way portion  146 . Wires  176  (similar to wires  76  described above) connect the PCB  160  (which carries light emitting elements similar to those described above) with a plug  178  (similar to the plug  78  described above). In contrast to the wire way  62  described above, the holder  140  does not fully support the wires  176  along the full length of the wires  176  all the way to the plug  178 . Rather, the wire way portion  146  stops at some point along the length of the wires  176 , leaving the wires  176  and the plug  178  to be not supported by the holder  140 . 
         [0075]    As shown in  FIG. 15 , the lens cover  162  is shown mounted in a recess in the holder  140 . The holder  140  is mounted to the transmission housing  123  which is supported by a housing  122  of the power tool  147 . A fastener hole  148  is shown in the housing  122 . The fastener hole  148  provides a place for a fastener such as a screw or bolt to connect the two halves of the clam shell type housing  122  together. While the fastener is not shown in  FIG. 16 , it will be appreciated that when the power tool  147  is fully constructed that a fastener will be located in the fastener hole  148  to connect the two halves of the clam shell housing  122  together. Other embodiments of the invention may connect the clamshells of the housing  122  in other ways. Some embodiments of the invention may include one piece housings or other types of housings than the clam shell housing shown in  FIG. 16 . The chin shroud  144  is located on the holder  140  and provides a housing for a portion of the wires  176  so that the wires  176  are not exposed outside of the power tool  147 . 
         [0076]      FIGS. 16 and 17  show the power tool  147  with part of the housing  122  removed. The housing  122  is a clam shell type housing and one of the clam shells is removed exposing the clam shell housing  122  located on the far side of the power tool  147 . The holder  140  is shown mounted to the transmission housing  123 . A fastener hole tube  150  located in the fastener hole  148  is shown. The wires  176  are routed around the hole tube  150  and are located in the interior  152  of the housing  122 . The wires  176  are terminated with a plug  178  also located in the interior  152  of the housing  122 . 
         [0077]    The interior  152  of the housing defines a space or pathway for the wires  176  and the plug  178 . The chin shroud  144  defines a wire way portion  146  through which the wires  176  are strung. The chin shroud  144  also includes retaining structure  154  which is set in a retaining area  156  defined by the housing  122 . When the two clam shells of the clam shell housing  122  are mounted together and fastened together with a fastener located in the fastener hole  148  and fastener hole tube  150 , the retaining structure  154  on the chin shroud  144  is trapped in the retaining area  156  thereby holding the chin shroud  144  and holder  140  in place on the power tool  147 . Operation of the light ring  138  is similar to that described in the embodiments above. 
         [0078]      FIG. 18  is a partial perspective cut-away view showing an end effector  128  associated with the power tool  147  extending through the lens cover  162  located in front of the PCB  160 . As described above, LEDs  184  (not shown in  FIG. 18 ) are located on the PCB  160  and configured to light the tool or workpiece being worked on by the power tool  147 . The wires  176  provide power between the PCB  160  and a power source connected via the plug  178  to power source. The wires  176  are located in the wire way portion  146  of the chin shroud  144  and the interior  152  of the housing  122 . The chin shroud  144  has the retaining structure  154  located in the retaining area  156  defined by the housing  122 . 
         [0079]      FIG. 19  represents a cross-sectional view of the holder  140  and transmission housing  123  subassembly. The holder  140  can be coupled to the transmission housing  123  using a plurality of snap features, or bayonet mechanisms  174  which are configured to interface with a corresponding L-shaped channel  175  defined within the transmission housing  123 . Disposed within a channel  179  defined by the holder  140  is the transparent cover  162 . As described below, the transparent cover  162  itself defines a transparent cover channel  180  which annularly supports an associated printed circuit board  160  having a plurality of surface mounted light emitting diodes (LEDS)  184 . As described in detail below, the circuit board  182  is held into the transparent cover channel  180  using a locking member  186  which is heat staked to the circuit board  160  to effect a solid non-rotatable fixation of the circuit board  160  to the transmission housing  123 . 
         [0080]    The holder  140  is coupled to a stepped portion  188  of the transmission housing  123 . The stepped portion  188  has a first surface  190  which is generally parallel to a centerline  192  of the tool  147 . Generally perpendicular to this surface is a second surface  194  which acts as an abutment for the holder  140 . The first surface  190  of the stepped portion  188  has a protruding flange  196  which functions as a locking feature to couple the holder  140  into the stepped portion  188 . The flange  196  has a ramped surface  198  which facilitates the snapping of a corresponding locking feature  200  on the holder  140  onto the stepped portion  188 . Defined within a second portion  202  the first surface  190  comprises the locking groove or channel  175 . The locking groove  175  is annularly formed within the second portion  202  or can be formed of a plurality of radially disposed intermittent coupling grooves. The locking feature  174  comprises a chamfered flange member  206  having a ramped interfaced surface  208  and opposed planar bearing surface  210 . The planar bearing surface  210  is configured to interface with a corresponding planar bearing surface  211  defined either on the flange  196  or locking groove or channel  175  defined within second portion  202  of the first surface  190 . 
         [0081]      FIG. 20  represents a perspective view of the holder  140  in subassembly form. The holder  140  contains a mounting member  208  which defines a plurality of radially disposed coupling slots  210 . The slots  210  are configured to accept a corresponding set of transparent cover snap coupling members  212 . The snap coupling members  212  are configured to bear against an inner surface  214  of the mounting member  208 . Protruding from the inner surface  214  are three depending coupling flanges which are configured to couple the holder  140  to the transmission housing  123 . 
         [0082]    The holder  140  has a generally cylindrical exterior surface  218 . The exterior surface  218  functions to encapsulate the transparent cover  162 , mounting member  208  and circuit board  160 . The mounting member  208  has a depending wire support member  220  having a center flanged portion  222  which defines a pair of generally elongated wire bearing slots  224 . The slots are configured to accept the pair of power wires  176  from the wire harness pig tail assembly. The wire support member  220  is generally disposed within the chin shroud  144  and facilitates the protection of the light source power wires. The mounting member  208  defines an axial through bore  226 . The through bore  226  has an inner surface  228  with a plurality of associated stand off flanges  230 . The stand off flanges  230  function to apply pressure onto the circuit board  160  when the mounting member is engaged with the holder  140 . Further defined within the inner surface  228  is a notch  232  configured to accept a wire harness strain relief member  234 . The wire harness strain relief member  234  has a pair of curved internal surfaces which accept the bent wires  176  in a manner to minimize the overall axial length of the holder  140 . 
         [0083]      FIG. 21  represents a rear perspective view of the transparent cover  162  and circuit board  160  subassembly. As shown, the circuit board  160  is generally circular and is disposed within the transparent cover channel  180 . The circuit board  160  defines a plurality of radially disposed notches  236  on the exterior radial periphery of the circuit board. The notches  236  accept corresponding flanges  286  which are defined radially within an inner bearing surface  240  of the transparent cover channel  180 . Defined within the transparent cover and adjacent to the flanges  238  are corresponding notches  242  which have a depth generally corresponding to the locational position of the circuit board  160 . After the circuit board  160  is placed within the channel  180 , the flanges  238  are melted, thereby fixably coupling the circuit board  282  within the transparent cover  162  using a heat staking process. 
         [0084]    The couplers or attachment mechanisms between the circuit board  160  and the transparent cover  162 , the holder  140  and the transmission housing  123 , or the holder  140  and the transparent cover  162  can take the form of a heat stake joint, a bayonet joint, or a locking flange within a slot, exemplary embodiments of which are described above. The couplers or attachment mechanisms are configured to withstand the extreme cyclic torsional loading associated with hand held power tools. In this regard, the joints are configured to prevent vibrational noise or damage to these components, especially to the PCB. 
         [0085]      FIGS. 22 and 23  represent cross-sectional perspective views of the subassembly shown in  FIG. 21 . Shown is the transparent cover channel  180 , a coupling flange  238 , relief member  234  and snap member  212 . The channel  180  defines an inner ledge  242  which axially supports the circuit board  160  in a position which axially locates the LEDs  184  at the proper distance from the transparent cover  162 . The distance allows for the proper focusing of the light from the LEDs on to a workpiece. 
         [0086]      FIG. 24  represents a front view of the transparent cover/circuit board subassembly shown in  FIGS. 21 and 22 . Shown is the positional position of the LEDs  184  with respect to the various snap and coupling features. While surface mounted LEDs  184  are shown and have their own particular advantages, it should be envisioned that non-surface mount LEDs could be used. Shown adjacent to the LEDs  184  is a plurality of surface mounted resistors  151  which are electrically coupled to the LEDs  184 . 
         [0087]      FIGS. 25-27  represent an alternate embodiment of a holder  340  having an alternate circuit board to transparent cover coupling mechanism. In this regard, the holder  340  contains a transparent cover  350  having an inner tubular member  352 . The inner tubular member  352  defines a generally L-shaped coupling channel  354 . The L-shaped coupling channel  354  defines a protruding locking feature  356  which engages a corresponding locking bayonet feature on the transmission housing. 
         [0088]    Further defined on the inner tubular member  352  is a plurality of coupling notches  358 . The notches  358  have a depth corresponding to the preferred locational position of the circuit board  382  within the transparent cover channel. Adjacent to the coupling notches  358  are corresponding coupling flanges  360  which are configured to be positioned within a corresponding set of notches defined within an inner surface of the circuit board  372 . As described above, the coupling flanges  360  are configured to be melted in a heat staking process to rotationally and longitudinally fix the circuit board  382  within the channel. As best seen in  FIG. 27 , the holder can define discrete apertures  368  to allow light to be emitted from the nose section of the tool onto the workpiece. The holder  340  may have elastomeric overmolding to prevent damage to the workpiece and to the tool if the tool inadvertently strikes the workpiece. 
         [0089]    The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure. 
         [0090]    Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. 
         [0091]    The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
         [0092]    When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
         [0093]    Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments. 
         [0094]    Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.