Abstract:
A power tool with a metal housing ( 12 ) has motor ( 20 ) positioned within the housing ( 12 ). An output ( 22 ), positioned within the housing ( 12 ), is coupled with the motor ( 20 ) and is adapted to drive a tool. An activation member ( 26 ) is coupled with the motor ( 20 ). A battery pack ( 30 ) is electrically coupled with the activation member ( 26 ). The activation member ( 26 ) energizes and deenergizes the motor ( 20 ), which in turn, drives the output ( 22 ).

Description:
FIELD AND BACKGROUND OF THE INVENTION 
     The present invention relates to power tools and, more particularly, to battery operated power tools with metallic housings. 
     In the power tool field, as battery technology continues to improve, tradesmen continue to switch to battery operated tools. Battery operated tools have housings that are of a polymeric material. The polymeric material provides lightweight characteristics with acceptable durability. Corded tools have long since utilized metallic housing. While the metallic housings do not adversely deter from the tools weight, they provide enhanced durability characteristics. 
     SUMMARY OF THE INVENTION 
     The present invention provides the art with a battery operated power tool with a metallic housing. The present invention provides the art with a lightweight battery operated tool with excellent durability. The power tool provides the corded user with a non-corded metallic housing tool. 
     In accordance with the first aspect of the invention, a power tool comprises a metallic housing. A motor is positioned inside the metallic housing. An output is coupled with the motor. The output is adapted to drive a tool. An activation member is coupled with the motor. A battery power source is electrically coupled with the activation member. The activation member energizes and deenergizes the motor which, in turn, rotates the output member. The activation member includes a switch which is electrically coupled with the battery power source and the motor. A polymeric subhousing surrounds the switch and is positioned in the metallic housing. The polymeric subhousing shields the activation member and motor from the metal housing. The polymeric subhousing includes a first subhousing shielding the activation member and a second subhousing shielding the motor. A barrier plate is positioned in the housing between the battery and an inner cavity of the metal housing. The barrier plate is a polymeric material. The output includes a transmission for changing speeds and torque of the output. The transmission includes a polymeric housing, first pinion or sun gear, first set of planetary gears, a first gear carrier and an insulating member. The insulating member is positioned between the first gear carrier and the first pinion gear to provide insulation against a possible failure route. The battery source has a polymeric housing coupled with the metal housing. 
     In accordance with a second embodiment of the invention, a battery operated power tool comprises a housing defining a cavity. The housing includes a pair of mating members each formed from a metallic material. A motor is received in the housing cavity. An activation member extends from the housing and is coupled with the motor. An output member is coupled with the motor and is adapted to drive a tool. A battery pack is coupled with the housing. The battery pack is electrically coupled with the activation member to energize and deenergize the tool. The power tool further includes a battery level indicator electrically coupled with the battery pack mounted on the housing. The power tool further includes a level indicator coupled with the housing which determines the levelness of the power tool in vertical and horizontal positions. The power tool further includes a gripping member. The power tool housing pair defines a handle portion. The activation member is housed in the handle portion and includes a switch electrically coupled with the battery. A polymeric housing surrounds the switch and is positioned in the handle portion of the metal housing. A barrier plate is positioned between the battery and the cavity of the metal housing. The output includes a transmission to change speed and torque of the output. The transmission includes a polymeric housing, first pinion or sun gear, first set of planetary gears, a first gear carrier and an insulating member. The insulating member is positioned between the first gear carrier and the first pinion gear to provide insulation against a possible failure route. 
     In accordance with the third aspect of the invention, a cordless drill comprises a metallic housing. A motor is positioned inside the metallic housing. An output is coupled with the motor. The output is adapted to drive a tool. An activation member is coupled with the motor. A battery power source is electrically coupled with the activation member. The activation member energizes and deenergizes the motor which, in turn, rotates the output member. The activation member includes a switch which is electrically coupled with the battery power source and the motor. A polymeric subhousing surrounds the switch and is positioned in the metallic housing. The polymeric subhousing shields the activation member and motor from the metal housing. The polymeric subhousing includes a first subhousing shielding the activation member and a second subhousing shielding the motor. A barrier plate is positioned in the housing between the battery and an inner cavity of the metal housing. The barrier plate is a polymeric material. The output includes a transmission for changing speeds and torque of the output. The transmission includes a polymeric housing, first pinion or sun gear, first set of planetary gears, a first gear carrier and an insulating member. The insulating member is positioned between the first gear carrier and the first pinion gear to provide insulation against a possible failure route. The battery source has a polymeric housing coupled with the metal housing. 
     Additional objects and advantages of the present invention will become apparent from the detailed description of the preferred embodiment, and the appended claims and accompanying drawings, or may be learned by practice of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a power tool in accordance with the present invention. 
     FIG. 2 is a side elevation view of FIG. 1 with one of the housing members removed. 
     FIG. 3 is a partially exploded view of FIG.  2 . 
     FIG. 4 is a cross-section view of FIG. 2 along line  4 — 4  thereof. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning to the figures, particularly FIG. 1, a power tool is illustrated and designated with the reference numeral  10 . The power tool  10  includes a housing  12  which includes a motor portion  14  with vents  15 , a handle portion  16  as well as a base portion  18 . A motor  20  is positioned in the housing  12 . An output  22  is coupled with the motor  20  and in this case includes a chuck  24 . An activation member  26  is associated with the handle portion of the housing  12 . The activation member is electrically coupled with the motor  20  as well as with the battery pack  30  which supplies the power to the power tool  10 . A gripping member  32  is coupled with the handle portion of the housing  12 . 
     The housing  12  includes a pair of mating housing members  34  and  36 . The mating members  34  and  36  have a clam shell design and come together to form the housing  12 . The two housing members  34  and  36  are manufactured from a metallic material. In the present case, aluminum is utilized. Aluminum provides a lightweight material at a reasonable cost. 
     The housing base  18  includes an aperture  40  to receive a battery level indicator  42 . The battery level indicator  42  includes an illumination mechanism  44  and an activation mechanism  46  to indicate to the user the amount of power remaining in the battery pack  30 . The battery level indicator  42  is electrically coupled via wires with the battery pack  30 . 
     The base  18  includes a battery receiving receptacle  50 . The battery receiving receptacle includes rails  52  and  54  and channels  56  and  58 . Also an electrical connector  60  is mounted in the housing. The battery receiving receptacle is like that illustrated in assignee&#39;s co-pending U.S. patent application Ser. No. 09/938,202 entitled “Power Tool with Battery Pack Ejector” filed Aug. 24, 2001, the specification and drawings of which are herein expressly incorporated by reference. 
     The battery pack  30  includes a housing  70  with a plurality of batteries (not shown) positioned within the housing. A release button  72  is coupled with a latch  74  to lock the battery on the metal housing  12 . Also the battery pack  30  includes rails  76  and  78  which fit into channels  56  and  58  to retain the battery pack  30  on the metal housing base  18 . Further details can be obtained from U.S. patent application Ser. No. 09/938,202 entitled “Power Tool with Battery Pack Ejector” filed Aug. 24, 2001, the specifications and drawings of which are herein expressly incorporated by reference. 
     The housing base  18  includes an opening  80  which has an overall rectangular design. A barrier plate  82  is positioned into the housing opening  80  to block off the housing cavity from the battery pack. The barrier plate  82  is ordinarily a polymeric material and prohibits dirt, debris and the like from entering into the housing cavity. Likewise, the barrier plate insulates the electrical connector  60  from contact with the metal housing  12 . The barrier plate fits into channels  84  in the housing base  18 . The channels  84  maintain the barrier plate in position so that the barrier plate  82  provides the desired characteristics. 
     The base  18  also includes a rail  88  which acts as a catch for the battery latch  78 . The rail  88  is formed from the metal housing and defines a side of the opening  80  which the barrier plate actively blocks. 
     A subhousing  100  is positioned within the handle portion of the housing  12 . The subhousing  100  has a configuration which fits within the handle portion  16  of the metal housing  12 . The subhousing  100  is of a claim shell design having two members  102  and  104 . The two members  102  and  104  surround the switch  106  of the activation member  26 . Thus, the subhousing members  102 ,  104  electrically insulate the switch  106  from the metallic housing  12 . The subhousing members  102 ,  104  are preferably transparent. This enables the assembler to view the switch and wires to ensure proper installation. The subhousing  100  is held in position, ordinarily by screws, on the metallic housing to maintain the spacing of the switch  106  within the handle portion  16  of the housing  12 . 
     A second subhousing member  110  is positioned around the motor  20 . The second subhousing  110  includes a pair of members  112  and  114 . The members  112  and  114  are arcuate and have projections  116  which extend into recesses  118  adjacent vents  15  on the inner surface of motor portion  14  of the housing  12 . The subhousing members  112  and  114  surround at least a portion of the motor  20 . Apertures  115  are positioned inside of the projections  116 . The apertures  115  enable air flow to pass between the motor and the outside through vents  15 . Thus, when the housing members  34  and  36  are assembled together, the motor  20  is spaced from the metallic housing  12 . Thus, the motor  20  is insulated and shielded from the metallic housing  12 . 
     A level indicating device  120  is positioned in an aperture  122  in the housing  12 . The level indicating device  120  indicates when the tool is in a vertical or horizontal position. The level indicating device is like that disclosed in assignee&#39;s co-pending U.S. patent application Ser. No. 10/075,927 entitled “Drill Level Indicator”, the specification and drawings of which are herein expressly incorporated by reference. 
     The output includes a transmission  130 . The transmission  130  is of a conventional three-stage speed reduction type having a polymeric housing  132 . A output spindle  134  extends from the motor  20  and is coupled with a first sun or pinion gear  136 . The first pinion gear  136  is coupled with a first set of planetary gears  140 . The planetary gears  140  rotate within a ring gear  142 . A first gear carrier  144  which includes an integral second sun gear  146  is coupled with the first set of planetary gears  140  via pins  148 . The second sun gear  144  is coupled with a second set of planetary gears  150 . The second set of planetary gears  150  rotates within a moveable ring gear  152 . The moveable ring gear  152  moves side to side to change the speed and torque of the transmission  130 . A transmission activation member  220  is positioned within an aperture  222  of the housing  12 . The activation member  220  slides within a channel  224  in the housing  12  to move the transmission  130  between different speeds and torque. The second set of planetary gears  150  is coupled with a second gear carrier  158 . The second gear carrier  158  has a third sun gear  160  integrally formed on the second gear carrier  158 . Pins  162  connect the second set of planetary gears  150  with the second gear carrier  158 . A third set of planetary gears  164  is coupled with the third sun gear  160 . The third set of planetary gears  164  rotates within a ring gear  166 . The third set of planetary gears  164  is coupled, via pins  172 , with the drill output spindle  176  which, in turn, is coupled with the chuck  24 . Also, a clutch mechanism  190  is coupled with the transmission  130 . 
     An insulating member  200  is positioned in the transmission  130 . The insulation member  200  is molded into the bore  201  of the first gear carrier  144  to insulate the first pinion gear  136  from the first gear carrier  144 . The insulation member  200  has a cylinder portion  202  and a flange portion  204 . The flange  204  has a diameter larger than the diameter of first pinion gear  136 . Thus, the insulation member  200  along with the plastic first set of planetary gears  140  and plastic ring gear  142  prohibit contact of metal parts from the pinion and in turn any possible failure route from continuing along the motor  20 . 
     The clutch mechanism  190  includes a clutch ring  210  which is rotated by the user to activate the clutch mechanism  190 . The clutch ring  210  includes a first metallic ring  212  and a second inner polymeric ring  214 . The rings  212 ,  214  act together to enable activation of the clutch mechanism  190 . The polymeric ring  214  provides an insulation barrier between the outer metallic ring  212  and the cavity of the power tool  10 . 
     While the above detailed description describes the preferred embodiment of the present invention, the invention is susceptible to modification, variation and alteration without deviating from the scope and fair meaning of the subjoined claims.