Power tools

#The invention relates generally to hand tools, and more particularly to electrically powered hand tools.

#Many hand tools that in the past were purely mechanical are now being replaced by motorized hand tools that perform the same function more quickly and with less effort by the user. Examples of conventional electrically powered hand tools are screwdrivers, drills, routers, sanders and a variety of saws, such as jigsaws, reciprocating saws and circular saws.

#Existing hand tools suffer from a number of deficiencies. For instance, hand tools, by their very nature are portable and thus easily stolen from job sites or storage areas. With battery powered tools, the weight of the tool is often excessive for comfortable extended use. Conventional electrically powered tools also do not allow the user to optimize the tool for use with the particular user's preferences, or with the specific requirements of a particular project or operating condition. For example, many tools are not adequately flexible in their operation to accommodate particular tasks easily and conveniently. By way of example, drill/drivers are used to drill holes and drive screws, however, existing designs do not always accomplish these functions in the most efficient or reliable matter. When driving screws, for instance, it is often difficult to accurately control the depth of the screw with existing drills. Similarly, existing drills do not provide sufficient control of torque, speed and/or number of revolutions. In some applications, the physical configuration of the drill is not well suited to allow access to the work sites. Various embodiments of the present invention address one or more of these and other deficiencies.

#FIG. 1 is a side elevation view of a hand tool constructed according to the present invention.

#FIG. 2 is a fragmentary cross-sectional detail taken along the line 2—2 in FIG. 1 and showing a fastening mechanism coupling the handle to the body of the tool.

#FIG. 3 is the detail of FIG. 2 showing an alternate method of providing electrical communication between the handle and the body of the tool.

#An electrically powered hand tool constructed according to the present invention is shown in FIG. 1 and generally indicated at 10. Tool 10 includes a body 12 with a housing 14, a handle 16 and a plurality of vents 18 for providing ventilation and cooling to a motor 20, which is contained within the housing. Tool 10 further includes a work element 22 in the form of a keyless chuck 28, a power source 24, a controller 26 and a manual clutch, or torque control, 30. Work element 22 is adapted to receive a bit, such as the screwdriver bit shown in FIG. 1 at 32 and is connected to a drive-train (not shown) such as is well known in the art. Examples of suitable torque control and drive-train mechanisms are disclosed in U.S. Pat. Nos. 4,161,242, 5,440,215, 5,458,206, 5,624,000 and 5,704,433, the disclosures of which are hereby incorporated by reference.

#Also shown in FIG. 1 is a reversing switch 34 that selectively reverses the direction in which the motor rotates the work element. Tool 10 also includes a user input in the form of a user-input button 38, a user interface 40 and a plurality of distance sensors 42. Controller 26 controls the operation of tool 10. This includes regulating the supply of power to motor 20, responding to signals from user inputs and sensors, and controlling the output on user interface 40. The features and operation of controller 26, user-input button 38, user interface 40 and distance sensors 42 will be described in more detail below.

#As shown, tool 10 is a battery-powered hand drill, however, it is within the scope of the present invention that hand tool 10 could also be in the form of a screwdriver, right angle drill, hammer drill or other known types of drills and drivers. For certain aspects of the present invention, the tool could also be a saw, router, sander or other form of powered hand tool. For example, when tool 10 is a reciprocating saw, work element 22 includes an arbor with a blade; when tool 10 is a router, work element 22 includes a collet with a router bit; when tool 10 is a sander, work element 22 includes a sanding head or a pad for receiving sandpaper; and when tool 10 is a jigsaw, work element 22 includes a blade holder to receive a jigsaw blade.