A method is provided for identifying a battery pack that is operably coupled to a battery charger. The method comprises: measuring voltage at a plurality of designated terminals of a first battery pack while the battery pack is coupled to the battery charger; determining how many of the designated terminals are connected to a reference voltage, such as battery positive; and identifying an attribute of the battery pack based on how many of the designated terminals are connected to the reference voltage.

A power tool includes a housing coupled to an electrical power source, a motor contained in the housing, and a motor control circuit that controls output speed of the motor. A light nut is coupled to the housing to illuminate a work surface. A light unit control circuit controls illumination of the light, unit. A switch unit is coupled to the housing and selectively operable to control the operation of the motor control circuit and the light unit control circuit. The light unit control circuit includes a timer configured to cause the light unit to illuminate a first brightness level when the switch unit is actuated, and to remain illuminated at the first brightness level for a predetermined time period after the trigger is actuated. The predetermined time period restarts if the switch unit is not deactivated before the end of the predetermined time period.

A lockable trigger mechanism for an electrical device, comprising: a housing; a trigger for biased movement relative to the housing; an actuator movably mounted to the housing such that in response to operation of the trigger, the actuator is movable along a movement axis from an OFF position inwardly of the housing towards an ON position, and movable along the movement axis from the ON position in a direction outwardly of the housing towards the OFF position; an electrical switch unit mounted to the housing for activation in response to movement of the actuator along the movement axis between its ON and OFF positions to close and open an electrical circuit of the electrical device respectively; and a locking mechanism comprising a first locking member, a second locking member and a biasing member configured for biasing movement of the first locking member relative to the second locking member.

The invention relates to an electric switch for electric devices. A changeover device is additionally provided for changing the direction of rotation of the electric motor. This changeover device includes a position sensor which is able to be operated from outside and features a haptic element.

An electric switch used in an electric device having a motor is provided. The electric switch comprises a switch housing, a plunger extending from the switch housing and switching from an off position into an on position of at least one contact of a contact system arranged within the switch housing via a movement, a circuit board; and a changeover device for changing a direction of rotation of the motor. The changeover device comprises a position encoder operated from outside, the position encoder is directly connected to a contact arm via two contact tongues; one contact tongue interacts with one conducting path to create a contact for the clockwise rotation of the motor in one position of the position encoder, and/or the other contact tongue interacts with other conducting paths to create a contact for the counterclockwise rotation of the motor in another position of the position encoder.

The invention relates to an electric switch for electrical devices having a circuit board immovably arranged in a switch housing said circuit board including on one of its surfaces the contact paths of a contact system as well as contact surfaces in the form of potentiometer tracks. The contact paths interact with sliding contacts of the contact system and the potentiometer tracks interact with additional sliding contacts in order to set the revolutions per minute or the torque of the electric motor, wherein movement of the plunger causes the sliding contacts of the contact system to come into contact with the associated contact paths, and, in this position of the plunger, which is the on position of the switch, the sliding contacts used for changing the direction of rotation are in the same way already in contact with the associated potentiometer tracks on the circuit board.

A pair of open/close and current-passing movable contact pieces is supported on a movable contact terminal such that the pair is rotatable along with the reciprocation of an operating element. An open/close movable contact is mounted on the open/close movable contact piece and is rotatably biased by a spring member. A current-passing movable contact is mounted on the current-passing movable contact piece. By moving the operating element, a restriction imposed on a position of the operating element is released so that the open/close movable contact piece is rotated by a spring force of the spring member whereby the open/close movable contact is brought into pressure contact with an open/close fixed contact mounted on a fixed contact terminal. The current-passing movable contact piece is rotated by the operating element so that the current-passing movable contact is brought into pressure contact with a current-passing fixed contact mounted on the fixed contact terminal.

A push-button switch capable of adjusting output power includes a housing. The housing includes a contact assembly and a power adjustment assembly therein. The contact assembly includes an upper terminal, a lower terminal and a connecting elastic plate below the upper terminal. A support seat is provided in the housing. An upper end of the support seat is provided with a first bracket. The first bracket is inserted through the connecting elastic plate. The first bracket is provided with a first slot. One end of the connecting elastic plate is fixedly connected to the upper terminal. Another end of the connecting elastic plate is engaged with the first slot. A drive mechanism is provided above the connecting elastic plate for driving the connecting elastic plate downward. The push-button switch has an ergonomic design.

A speed control switch includes a base. An upper end of the base is provided with a switch assembly. A side of the base is provided with a PCB board and a slide terminal. The PCB board is provided with a first contact plate. The slide terminal is slidably connected with the first contact plate. The base is provided with a trigger assembly for driving the slide terminal to slide along the first contact plate and to close the switch assembly. The speed control switch can regulate the speed of a motor precisely. The structure is compact to reduce the size of the switch, so that it is convenient for operation.

A power tool includes a housing coupled to an electrical power source, a motor contained in the housing, and a motor control circuit that controls output speed of the motor. A light nut is coupled to the housing to illuminate a work surface. A light unit control circuit controls illumination of the light, unit. A switch unit is coupled to the housing and selectively operable to control the operation of the motor control circuit and the light unit control circuit. The light unit control circuit includes a timer configured to cause the light unit to illuminate a first brightness level when the switch unit is actuated, and to remain illuminated at the first brightness level for a predetermined time period after the trigger is actuated. The predetermined time period restarts if the switch unit is not deactivated before the end of the predetermined time period.