Abstract:
In accordance with the invention, a drill comprises a drill housing with a handle portion and a driver portion and incorporating a circumferential workpiece illumination system. An electrical drill motor is located in the driver portion. The drill motor has an output shaft for coupling output rotary power. An electrical switch controls the operation of the drill motor. The electrical switch it is located on the handle portion of the drill housing. A chuck is coupled to the output shaft of the drill motor.

Description:
TECHNICAL FIELD 
       [0001]    The invention relates to electric drills with a quasi-circumferential workpiece lighting structure for lighting visible portions of the work area. 
       CROSS REFERENCE TO RELATED APPLICATIONS 
       [0002]    Not applicable. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0003]    Not applicable. 
       BACKGROUND OF THE INVENTION 
       [0004]    Electrically powered drills remain one of the mainstays of every tool box, whether it be that of the homeowner or construction professional. Even going back to the 1950s, electrical drills were in very common use in the home, with companies like Sears Roebuck &amp; Co. and others turning out high quality products at modest prices in what was then a very old technology. 
         [0005]    Indeed, the most modern form of the electric drill, that is a pistol shaped device with a multi-fingered chuck that could be tightened using a conical gear key, followed closely the development of these chucks by the Jacobs Manufacturing Company in or about 1902. Except for the introduction of a switch to reverse drive direction and the introduction of rechargeable batteries in recent years, the technology remains essentially static. 
         [0006]    While they have been available on the market for many years, about 20 years ago, electric powered drills and other tools came into prominence. Because the structural aspects of these tools which performed directly the work for which they are intended differed from earlier tools only by the substitution of battery power, designs largely emulated conventional tools powered by house current. 
         [0007]    While the completion of battery power is a primary issue in battery powered drills, workpiece illumination lights have been employed in battery powered drills. In the case of tools, such as soldering irons, lights are also employed. Because these devices are always attached to house current, the lighting mechanism can consume relatively high power and deliver large amounts of light. Because of the nature of light sources, this light tends to be somewhat randomly spread about and results in somewhat effective illumination of the workpiece. Generally, such lights are positioned at a point around the circumference of the chuck aligned with the handle of the drill. 
         [0008]    Prior art electric drills, such as the electric drill illustrated in U.S. Pat. No. RE 38,729 also use light sources. In the case of U.S. Pat. No. RE 38,729, two light sources are located on the sides of the drill, in other words, at ninety degrees to the handle of the drill. 
       SUMMARY OF THE INVENTION 
       [0009]    In accordance with the invention, it has been recognized that drills often lose their charge for reasons unrelated to the amount of work being done. For example, it has been recognized that in many circumstances, drills are operated to perform a task but are positioned improperly, requiring that the work be repeated. Worst than that, sometimes a new workpiece needs to be obtained and this involves waste of workpieces and the materials from which they are made with consequent loss of any labor which has been expended to make the same. Added to this is associated environmental damage. 
         [0010]    In an effort to address these problems, prior art electrical drills may be provided with a light. Generally, this has involved the use of a light emitting diode which may extend from the body of the electrical drill. Alternatively, the prior art shows the use of a light emitting diode which is recessed inside the drill. Typically, the light emitting diode is aimed at the place where the drilling or other operation, such as tightening or unscrewing of a screw, is done. 
         [0011]    In accordance with the invention, high efficiency in lighting is provided by illuminating principally those areas of the workpiece which are likely to be visible to the user of the tool and/or likely to need illumination. 
         [0012]    Importantly, as has been recognized in accordance with the invention, the positioning of lights aligned with the bottom of the drill and its handle suffers from the inefficiency of not illuminating that portion of the workpiece adjacent the top of the drill, i.e. that portion of the workpiece opposite the handle. Since the most visible part of the workpiece is that portion of the workpiece adjacent the left side of the drill in the case of a right-handed user and adjacent the right side of the drill in the case of a left-handed user, and the second most visible part is that portion of the workpiece opposite the handle, maximum efficiency of illumination and provision of the tool which will work well for both right-handed and left-handed users is served by the provision of lighting on opposite sides of the drill and adjacent the top of the drill. 
         [0013]    This approach will also accommodate both right-handed and left-handed use of the inventive drill by a single individual, something which particular jobs may require. 
         [0014]    Still further efficiency can be provided by the provision of switches associated with each of the lights, so that illumination may be tailored to a particular user&#39;s style or a particular job&#39;s requirements. 
         [0015]    In accordance with the invention, a drill comprises a drill housing with a handle portion and a driver portion. An electrical drill motor is located in the driver portion. The drill motor has an output shaft for coupling output rotary power. An electrical switch controls the operation of the drill motor. The electrical switch is located on the handle portion of the drill housing. A chuck is coupled to the output shaft of the drill motor. 
         [0016]    A light is positioned to principally illuminate those areas of the workpiece which are likely to be visible to the user of the tool. 
         [0017]    The inventive drill also comprises charge state measuring circuitry having a plurality of output terminals. Actuation of the output terminals or a combination of output terminals each corresponds to a particular state of charge. A red indicator light is coupled to one of the output terminals. One of the output terminals indicates a relatively poor state of charge. A green indicator light is coupled to an other one of the output terminals. The other one of the output terminals indicates a relatively good state of charge. A charge test switch actuates the charge state measuring circuitry. 
         [0018]    The charge state measuring circuitry further comprises an output terminal for driving a yellow light. The charge state measuring circuitry actuates the yellow light to indicate a condition which is neither good nor poor. It also actuates the green light and the yellow light simultaneously to indicate a battery charge condition that is better than that indicated by the yellow light but not as good as that indicated by the green light. The measuring circuitry also actuates the red light and the yellow light simultaneously to indicate a battery charge condition that is worse than that indicated by the yellow light but not as bad as that indicated by the red light. The indicator lights may be located on the left side of the handle portion of the drill housing. 
         [0019]    In accordance with the invention, a green directional indicator and a red directional indicator are included to indicate movement of the drill chuck, with the green indicator indicating movement in a clockwise direction and the red indicator indicating movement in a counterclockwise direction. 
         [0020]    The indicator lights may be located on the top of the driver portion of the drill housing. The red and green indicator lights and the charge test switch may be located adjacent the left side of the drill in the case of a drill primarily intended for a right-handed user. 
         [0021]    A first workpiece illuminating light may be provided on the left-hand side of the drill, and a second workpiece illuminating light may be positioned on the top of driver portion of the drill. A light may be positioned to principally illuminate those areas of the workpiece which are likely to be visible to the user of the tool and may comprise a plurality of light sources positioned circumferentially about a forward end of the driver portion. A workpiece illumination light may be positioned on the top of driver portion of the drill to illuminate more visible portions of the workpiece. Another workpiece illumination light may be positioned adjacent the bottom of driver portion of the drill housing to illuminate remaining more visible portions of the workpiece not likely to be covered by the hand of the user and the handle portion of the drill housing. 
     
    
     
       BRIEF DESCRIPTION THE DRAWINGS 
         [0022]    The operation of the invention will become apparent from the following description taken in conjunction with the drawings, in which: 
           [0023]      FIG. 1  illustrates a general implementation of a drill in accordance with the present invention; 
           [0024]      FIG. 2  is a front view of the drill of  FIG. 1 ; 
           [0025]      FIG. 3  is a left side view of the drill of  FIG. 1 ; 
           [0026]      FIG. 4  is a front view showing another illumination design; 
           [0027]      FIG. 5  illustrates an alternative embodiment of the drill of the present invention; 
           [0028]      FIG. 6  illustrates another alternative inventive illumination structure; 
           [0029]      FIG. 7  illustrates an indicator useful in the present invention; and 
           [0030]      FIG. 8  illustrates a detail of the illumination of  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0031]    As illustrated in  FIG. 1 , an electric drill  10  including an illumination system particularly configured in a manner which maximizes the efficiency of the use of electricity for illumination in an electrical power driving device such as a drill and constructed in accordance with the present invention is illustrated. 
         [0032]    Drill  10  includes a handle portion  12  and a driver portion  14 . Driver portion  14  comprises a neck  16 . A chuck  18 , of conventional design, is mounted on a spindle  20 . In accordance with the preferred embodiment, it is contemplated that chuck  18  may be any conventional hex socket chuck, as a wide variety of tool bits having mountings suitable for such chucks are readily available on the market. 
         [0033]    Alternatively, a multi-fingered chuck, for example one of the type using a serrated sleeve may be employed. Alternatively, a multi-fingered chuck employing a conical gear pin key (such as that sold by Jacobs Manufacturing) may also be advantageously employed in accordance with the present invention. Spindle  20  is coupled to a motor, not illustrated, but of conventional design, housed within driver portion  14 . In accordance with the invention, drill  10  is capable of both forward and reverse movement. The same is achieved using conventional circuitry. 
         [0034]    Driving direction is selected by an on/off switch  22 . Switch  22  includes a lever operator  24  mounted for rotation about a pivot bar  26 , illustrated in hidden lines in  FIG. 1 . Lever operator  24  is mounted with a conventional spring mechanism which biases lever operator  24  in the position illustrated in  FIG. 1 . 
         [0035]    Upon the application of pressure to the upper portion  28  of lever operator  24 , in the direction of arrow  30 , spindle  20  is caused rotate in the clockwise direction, thus causing drill bit  32  to rotate clockwise and drill into a workpiece, for example creating a hole or driving a screw into a workpiece. It is noted that a drill bit  32  is shown for purposes of illustration, but that drill  10  may be used to rotate a wide variety of tools, such as bits with conventional slot and Philips screwdriver tips of all types and sizes, hex wrench bits and specialized tools such as star drivers and four sided drivers. 
         [0036]    Upon the application of pressure to the lower portion  34  of lever operator  24 , in the direction of arrow  36 , spindle  20  is caused rotate in the counter-clockwise direction, thus causing drill  32  to rotate counter-clockwise and withdrawn from the workpiece, leaving behind the hole. In accordance with a preferred embodiment of the invention, a three position switch  38  with a slider selection member  40  changes the state of inventive drill  10  from a first position illustrated in dashed lines, where it is operable and lights illuminate the workpiece, to, when slider member  40  is in the position illustrated at  40   a,  an “on” position where the drill will operate but no illumination is provided, when slider member  40  is illustrated in solid lines. 
         [0037]    Slider member  40  may also be put in the locked position shown in dashed lines as indicated by reference numeral  40   b,  in which position neither tool operation nor illumination is provided. Such locking and turning on of lights using a slider switch is conventional and three position switch  38  may be of any conventional design. 
         [0038]    Light  44  is oriented in a direction which causes it to illuminate the workpiece as illustrated in  FIG. 1 . In accordance with a preferred embodiment, a marking showing the position for the application of force by the finger of the user to achieve a forward or clockwise drilling operation takes the form indicated by forward alphanumeric indicator  46 . Likewise, rearward or counterclockwise motion may be achieved by squeezing switch  22  in the direction indicated by arrow  36  adjacent rearward alphanumeric indicator  48 . For ease of operation a second forward alphanumeric indicator  50  and a second rearward alphanumeric indicator  52  are provided on the opposite side of the drill as illustrated in  FIG. 3 . 
         [0039]    The inventive drill  10  further comprises a battery testing switch  54 . Adjacent battery testing switch  54  is a red light  56  which is positioned beside a yellow light  58 , which in turn, is positioned beside a green light  60 . Lights  56 - 60  are connected to a battery testing circuit, with actuation of a red light indicating a very weak battery, and a weak battery indicated by simultaneous lighting of red light  56  and yellow light  58 . Actuation of only yellow light  58  indicates a weakening battery. Actuation of yellow light  58  and green light  60  indicates a relatively strong battery condition. Finally, actuation of green light  60  indicates a battery which is substantially fully charged. These various actuation combinations may be obtained from a conventional voltage measuring circuit and a suitable gating arrangement driving the lights as are within the design capability of one of ordinary skill in the art. 
         [0040]    The presence of state of charge indication circuitry is as indicated by an indicia  61  of conventional configuration. The position of switch  54  is particularly advantageous, being on the left side of the drill handle  12  because a right handed user is relatively unlikely to accidentally actuate switch  54 . The result is a very accessible state of charge indicator. On the other hand, because the indicator lights  56 - 60  are also visible when the drill is held in the right hand, access is particularly easy. Likewise, switch  54  is easily accessible to the left hand when the drill is held in the normal position by the right-hand, which also promotes ease-of-use. 
         [0041]    In accordance with a preferred embodiment of the invention, lights, for example light emitting diodes, are provided to illuminate the workpiece. Generally, that portion of the workpiece, which lies adjacent to the handle, is not easily visible or commonly visible to the user. Accordingly, the provision of lights in such a position, for example as illustrated by light  62  in  FIG. 4  may not be the most advantageous arrangement, because it illuminates portions of the workpiece which are not visible. Accordingly, in accordance with the invention, as illustrated in  FIGS. 2 and 3 , lights  64 ,  66  and  68  are provided in positions which are more efficient. More particularly, light  64  on the left-hand side of the drill illuminates the most visible portions of the workpiece. 
         [0042]    Likewise, light  66  positioned on the top of driver portion  14  of drill  10  illuminates relatively visible portions of the workpiece. Finally, light  68  illuminates the remaining portion of the workpiece not likely to be covered by the hand of the user and handle portion  12  of drill  10 . 
         [0043]    An alternative embodiment of the inventive drill  110  is illustrated in  FIG. 5 . Drill  110  is similar to drill  10  except for the inclusion of a light illumination package comprising lights  164  and  166 . This arrangement takes care of the two most effective lighting areas being at the top and the left-hand side of the drill in the case of a right-handed user. This configuration may be reversed for left-handed users with the reconfiguration of light  164  to a position on the right side of the drill (as opposed to the left side of the drill). 
         [0044]    In accordance with the invention, as illustrated in  FIG. 6 , it is contemplated that a drill  210  may comprise three lights  264 ,  266  and  268 . This results in added illumination, as well as some additional lighting on the right side of the drill. 
         [0045]    As an alternative to the state of charge indicator illustrated in the embodiment of  FIGS. 1-3 , the inventive drill may have an indicator arrangement as illustrated in  FIG. 7 . In accordance with this embodiment, the inventive drill includes an indicator  470  located on the top of the drill  410 . 
         [0046]    Referring to  FIGS. 7 and 8 , inventive drill  310  further comprises a battery testing switch  354  located on the top of the housing. Adjacent battery testing switch  354  is a window  355  behind which is mounted a red light  356 . In accordance with the present invention, window  355  is made of a transparent plastic which allows light from light  356  to exit. In accordance with the preferred embodiment, light  356  as well as the other lights included in the various embodiments of the invention are light emitting diodes, although other light sources, principle, may be used. Window  355  and light  356  are positioned circumferentially beside the second window  357 , behind which is positioned a yellow light  358 . A third window  359  is positioned circumferentially beside window  357 . A green light  360  is positioned behind window  359 . 
         [0047]    Lights  356 - 360  are connected to a battery testing circuit, with actuation of a red light indicating a very weak battery. A weak battery is indicated by simultaneous lighting of the red light  356  and yellow light  358 . Actuation of only yellow light  358  indicates a weakening battery. Actuation of yellow light  358  and green light  360 , simultaneously, indicates a relatively strong battery condition. Finally, actuation of green light  360  indicates a battery which is substantially fully charged. These various actuation combinations may be obtained from a conventional voltage measuring circuit and a suitable gating arrangement driving the lights. The presence of state of charge indication circuitry is indicated by an indicia  361  of conventional configuration. 
         [0048]    The position of switch  354  is particularly advantageous, being on the top of the drill driver portion  314  because it is not likely to be accidentally actuated. The result is a very accessible state of charge indicator. On the other hand, because the indicator lights  356 - 360  are also visible when the drill is held in either hand, access is particularly easy. This promotes ease-of-use. 
         [0049]    Indicator  370  also includes green indicator lights  372  which is actuated when the inventive drill  310  is turned on in the forward or clockwise direction. Similarly, red lights  374  is actuated when drill  310  is turned on in the reverse or counterclockwise direction. 
         [0050]    In accordance with a preferred embodiment of the invention, indicator lights  372  and  356  are different colors, in order to avoid potential misinterpretation of the signal associated with light actuation. Likewise, indicator lights  374  and  360  are different colors, also in order to avoid potential misinterpretation of the signal associated with light actuation.