Abstract: The present invention provides a power tool with a hand proximity detector to detect the hand of an operator and a trigger circuit operable with the detector to control the operation of a light in the housing or to provide a safety lockout function.

Abstract: A miter saw is provided having a support arm that is pivotally mounted to a base for adjustment of a pivot angle, the saw including a detent mechanism to provide pivot stops at common bevel angles, such as at 45° L, 0° (vertical), and 45° R. The detent mechanism includes a step-shaped, arcuate detent block mounted to the support arm in an adjustable manner to permit the accurate setting of the block in a home position. In an embodiment, a pair of set screws acts against opposite ends of the detent block, permitting precise adjustment in either direction. An axially movable detent pin is mounted to the base to contact against stepped surfaces of the block. The arm is free to pivot within a bevel angle range defined by one of the surfaces. Steps between surfaces act as a pivot stops, abutting the pin at a corresponding predetermined angle of the arm.

Abstract: A circle cutting accessory for use with a generally cylindrical powered rotary hand tool with an output shaft at one end thereof, the tool having a second accessory attached to the one end, with the second accessory having at its distal end an outwardly extending flange with a first predetermined diameter around a substantial portion of the circumference thereof, the circle cutting accessory including a generally flat housing for receiving and supporting the second accessory and the rotary hand tool. The housing has an upper support surface with an aperture through which a cutting tool attached to the output shaft can pass. The circle cutting accessory further includes a generally horizontal elongated arm mounted to the housing and extends outwardly from the housing. A circle center and sizing elongated member is slidably attached to the arm and has a centering pin extending downwardly therefrom at one end portion.

Abstract: The present invention is for an ambidextrous lockout switch system for use with a power tool. With the system of the present invention in place, a multi-step process must be carried out before the power tool can be activated. The system is adapted for the process to be carried out with either a left or a right hand. The present invention includes a handle body having a switch trigger or lever blockable by a barrier. The barrier is movable with either a left of a right lockout button, with the right lockout button being operably linked to the left lockout button. The system includes also a spring, which is mechanically coupled to the barrier. The spring effectively restores the barrier to a position in which the barrier blocks actuation of the switch trigger or lever.

Abstract: A DC—DC voltage converter that is capable of increasing as well as decreasing the voltage of a battery pack for application to a power tool or other load. The converter thereby enables different voltage batteries to be used with power tools that have motors that operate at different voltages. The voltage conversion is accomplished by using a relatively high speed switching circuit wherein the duty cycle of the switching circuitry varies the output voltage. An alternative embodiment utilizes feedback control circuitry to automatically adjust the duty cycle so that the speed of the motor, which is a function of the voltage applied to it, would be held generally constant.

Abstract: A bevel miter saw is provided having a switch handle that is ergonomically rotatable to a selected predetermined position as provided by a detent mechanism. An embodiment of the detent mechanism includes a detent member having radially directed slots, and a detent pin movable in a generally radial direction relative to the slots. Furthermore, a safety feature is provided wherein the detent pin is mounted to a lever including a projection that obstructs a trigger switch in the handle when the detent pin is not engaged in one of the detent slots so that the handle could rotate.

Abstract: The present invention is for an ambidextrous lockout switch system for use with a power tool. With the system of the present invention in place, a multi-step process must be carried out before the power tool can be activated. The system is adapted for the process to be carried out with either a left or a right hand. The present invention includes a handle body having a switch trigger or lever blockable by a barrier. The barrier is movable with either a left or a right lockout button, with the right lockout button being operably linked to the left lockout button. The system includes also a spring, which is mechanically coupled to the barrier. The spring effectively restores the barrier to a position in which the barrier blocks actuation of the switch trigger or lever.

Abstract: A front-accessible bevel locking system for use with a power tool, including a mechanism for locking the power tool into a selected tilt or bevel position for bevel angle cuts. The bevel locking mechanism has a lever attached to a link rod by a cam mechanism such that, as the lever is moved to the locked position, the link rod holds a pivot support for the power tool at a bevel angle.

Abstract: A miter saw is provided having a support arm that is pivotally mounted to a base for adjustment of a pivot angle, the saw including a detent mechanism to provide pivot stops at common bevel angles, such as at 45° L, 0° (vertical), and 45°R. The detent mechanism includes a step-shaped, arcuate detent block mounted to the support arm in an adjustable manner to permit the accurate setting of the block in a home position. In an embodiment, a pair of set screws acts against opposite ends of the detent block, permitting precise adjustment in either direction. An axially movable detent pin is mounted to the base to contact against stepped surfaces of the block. The arm is free to pivot within a bevel angle range defined by one of the surfaces. Steps between surfaces act as a pivot stops, abutting the pin at a corresponding predetermined angle of the arm.

Abstract: A circular saw including a motor housing having a first end portion and a second end portion, a motor assembly disposed within the housing, a rotary blade assembly having a predetermined weight mounted to the first end portion of the motor housing, and a battery pack having a predetermined weight disposed on the second end portion of the motor housing. The battery pack and the rotary blade assembly are configured and arranged to be in longitudinal alignment with one another, and the longitudinal alignment of the battery pack with the rotary blade assembly promotes counterbalancing between the predetermined weight of the rotary blade assembly and the predetermined weight of the motor housing.

Abstract: A voltage indicator circuit for indicating a charge state of a power supply, such as a battery pack, is disclosed. The voltage indicator circuit includes a voltage divider circuit that connects to a plurality of series connected light sources, such as light emitting diodes. Upon activation of the voltage divider circuit, one or more of the light sources may illuminate to provide a visual indication of the current charge state of the power supply. More particularly, the number of light sources illuminated varies according to the charge state of the battery pack.

Abstract: An electric motor having a regenerative braking capability is described which has several embodiments, each of which utilize two pairs of brushes, each pair of which has individual brushes positioned on diametrically opposite sides of the commutator. One pair is positioned for preferably optimally running the motor while the other pair of brushes is used solely for braking purposes. For normal motor or running operation, a motor switch assembly interacts with an activating mechanism to physically lift the pair of braking brushes from the surface of the commutator and also ensures that the running brushes come into contact with the commutator. When the motor switch assembly is switched to stop the motor, the switch assembly causes the activating mechanism to first lift the running brushes from the surface of the commutator and then place the braking brushes onto the commutator surface.

Abstract: A combined rotary hand tool and accessory attachment includes a rotary hand tool having an output shaft and a nose end associated with the shaft. An accessory attachment has a mounting portion configured for releasable attachment to the nose end and an engagement formation provided to the nose end and the mounting portion and configured so that the mounting portion is securable upon the nose end upon an approximate ¼ relative rotation.

Abstract: A circle cutting accessory for use with a generally cylindrical powered rotary hand tool with an output shaft at one end thereof, the tool having a second accessory attached to the one end, with the second accessory having at its distal end an outwardly extending flange with a first predetermined diameter around a substantial portion of the circumference thereof, the circle cutting accessory including a generally flat housing for receiving and supporting the second accessory and the rotary hand tool. The housing has an upper support surface with an aperture through which a cutting tool attached to the output shaft can pass. The circle cutting accessory further includes a generally horizontal elongated arm mounted to the housing and extends outwardly from the housing. A circle center and sizing elongated member is slidably attached to the arm and has a centering pin extending downwardly therefrom at one end portion.

Abstract: An articulation lock that includes a first housing, a second housing, and a lockable connection assembly for pivotably connecting the first housing and the second housing together. The lockable connection assembly includes a plurality of apertures arranged upon a portion of the second housing and at least two lock pins, where each of the lock pins is seated within a cavity located within the first housing. The assembly further includes at least one biasing element for creating a biasing force upon each of the lock pins such that each of the lock pins is biased toward the second housing to prevent relative rotation of the first housing with respect to said second housing and also with respect to an engaging member attached to the second housing. The engaging member includes a plurality of protrusions, with one of the protrusions corresponding to each of the apertures in the second housing.

Abstract: The present invention provides a power tool with a hand proximity detector to detect the hand of an operator and a trigger circuit operable with the detector to control the operation of a light in the housing or to provide a safety lockout function.

Abstract: An apparatus for preventing disengagement of an axially movable and rotatable flexible core of a flexible shaft attachment, which has a driven end and a handpiece end, and the driven end has a ferrule for attachment to a rotary power tool. The rotary power tool has an exteriorly threaded hollow output shaft with a first predetermined interior depth for receiving the base end of tool bits that can be used with the power tool, and the flexible shaft attachment has a drive cap attached to the output shaft, and the drive cap has an aperture sized and shaped for receiving the core in fixed rotating engagement. The apparatus includes a generally cylindrical stop plug having an open end portion and a closed end portion, and a cylindrical chamber extending from said open end portion to said closed end portion. The open end portion has an outward extension adapted to engage the end of the output shaft and be held in place by the attached drive cap, and the chamber is capable of receiving the core therein.

Abstract: A ferrule for coupling an attachment to a rotary hand tool unit of the type that has a housing with a nose portion through which a rotary output shaft extends. The nose portion has at least one groove extending generally circumferentially around at least a part of the nose portion, so that a groove portion is located on opposite sides of the nose portion. The ferrule includes a generally hollow cylindrical body with interior and exterior surfaces with an open mounting end portion and a smaller opposite end portion to which the attachment is mounted. The open mounting end portion fits on the nose portion of the housing when the ferrule is coupled to the rotary hand tool.

Abstract: The quick-release chuck for a rotary power tool is provided for holding a tool bit. The chuck includes a barrel having an axial bore to receive the tool bit and an axially movable sleeve operable to position a locking member to selectively lock or release the tool bit. A proximal end of the chuck near the housing of the power tool includes a low-profile collar which holds a spring in compression against the sleeve, biasing the sleeve in a distal, locked position. The components of the chuck may advantageously be assembled in a stacked manner. The low-profile collar permits the chuck to occupy a minimal length and to be positioned with a minimal separation from the housing of the power tool for enhanced safety.