A method for detecting a transmission backlash in a hand-held power tool, the hand-held power tool comprising a drive motor that has a drive shaft, a tool spindle, and a transmission that, in respect of drive, connects the drive shaft to the tool spindle, includes actuating, in a first actuation, the drive motor at least until the value of a first variable, representing a drag torque, is at least approximately constant. The method includes, during the first actuation, determining a value of a second variable which is associated with the rotation of the drive shaft of the drive motor during the first actuation, and determining a value of a third variable, representing a transmission backlash, based upon a change in the second variable during the first actuation.

A power tool, such as a hammer driver-drill (1), includes a spindle (26) that is axially and rotatable supported inside a metal gear case (41). A first cam (83) is affixed to the spindle so as to rotate therewith and is housed in the gear case (41). A second cam (84) is disposed around spindle such that it is rotatable separately with respect to the spindle and can be brought into contact with the first cam. Hammer-switching levers (95) are movable relative to the gear case between an advanced position, at which rotation of the second cam is restricted (blocked), and a retracted position, at which the rotational restriction on the second cam is released. Receiving members (89) are respectively interposed between the gear case and the hammer-switching levers and are configured to absorb vibration generated when a hammering operation is being performed using the power tool.

A power tool for chiseling and drilling includes a housing, a motor disposed inside the housing, and a pneumatic percussion mechanism. An operation mode selector switch is disposed on the housing and has a first operation mode setting and a second operation mode setting where the first operation mode setting activates the pneumatic percussion mechanism and the second operation mode setting deactivates the pneumatic percussion mechanism. A valve has an inlet-port formed inside the guiding tube and an outlet-port formed outside the guiding tube where the valve is connected to the operation mode selector switch. The valve is closed in the first operation mode setting which disables an air exchange between the inlet-port and the outlet-port and the valve is open in the second operation mode setting which enables the air exchange between the inlet-port and the outlet-port.

An electric power tool includes a motor, a spindle, a first vibration cam, a housing, a second vibration cam, a vibration switching member, and a plurality of biasing members. The spindle is rotatable by the motor. The first vibration cam is fixed to the spindle. The first vibration cam is located inward of the housing. The second vibration cam is located inward of the housing. The second vibration cam is configured to be in friction with the first vibration cam. The vibration switching member switches between a rotatable condition and an unrotatable condition of the second vibration cam with respect to the housing. The plurality of biasing members bias the vibration switching member.

A work tool includes a motor, a driving mechanism, a body housing and a handle. The driving mechanism is configured to perform an operation of linearly reciprocating the tool accessory along a driving axis extending in a front-rear direction. The handle includes a grip part extending substantially in an up-down direction, and a battery-mounting part provided on a lower side of the grip part. An upper end portion of the handle is connected to a rear end portion of the body housing via an elastic member so as to be movable relative to the body housing. A lower end portion of the handle is connected to the rear end portion of the body housing so as to be rotatable relative to the body housing, around a rotation axis extending in a left-right direction. The rotation axis is located on a lower side of the battery-mounting part.

A rotary power tool comprises a drive mechanism including an electric motor and a transmission, a housing enclosing at least a portion of the drive mechanism, a spindle rotatable in response to receiving torque from the drive mechanism, a first ratchet coupled for co-rotation with the spindle, a second ratchet rotationally fixed to the housing, a sleeve bushing on an interior of the housing, and a bearing arranged between the spindle and the sleeve bushing and rotatably supporting the spindle. The bearing has an outer race. The spindle is movable relative to the housing in response to contact with a workpiece, causing the first and second ratchets to engage and the spindle to reciprocate while rotating. The outer race of the bearing moves along the sleeve bushing during reciprocation of the spindle when the first ratchet and second ratchet are engaged.

A rotary hammer adapted to impart axial impacts to a tool bit. The rotary hammer includes a housing, a motor supported by the housing, a spindle coupled to the motor for receiving torque from the motor, causing the spindle to rotate, a reciprocation mechanism operable to create a variable pressure air spring within the spindle, an anvil received within the spindle for reciprocation in response to the pressure of the air spring, the anvil imparting axial impacts to the tool bit, a bit retention assembly for securing the tool bit to the spindle, and an electromagnetic clutch mechanism switchable between a first state, in which the reciprocation mechanism is enabled, such that the anvil imparts axial impacts to the tool bit, and a second state, in which the reciprocation mechanism is disabled, such that the anvil ceases to impart axial impacts to the tool bit.

A work tool includes a motor, a driving mechanism, a housing, a handle, a detecting mechanism and an elastic support part. The detecting mechanism is configured to detect information corresponding to an operating state of the work tool. The elastic support part supports the detecting mechanism so as to be movable relative to the housing in at least two of a front-rear direction, an up-down direction and a left-right direction. The elastic support part includes at least one elastic member disposed between the detecting mechanism and the housing. The elastic support part has respectively different spring constants in the at least two directions.

A work tool includes a motor, a driving mechanism, a body housing and a handle. The driving mechanism is configured to perform an operation of linearly reciprocating the tool accessory along a driving axis extending in a front-rear direction. The handle includes a grip part extending substantially in an up-down direction, and a battery-mounting part provided on a lower side of the grip part. An upper end portion of the handle is connected to a rear end portion of the body housing via an elastic member so as to be movable relative to the body housing. A lower end portion of the handle is connected to the rear end portion of the body housing so as to be rotatable relative to the body housing, around a rotation axis extending in a left-right direction. The rotation axis is located on a lower side of the battery-mounting part.

A rotary hammer includes a motor, a manipulation member, a main switch, a mode-switching member, a first locking member and a second locking member. The first locking member is configured to selectively lock the manipulation member in an OFF position according to a switching position of the mode-switching member. The second locking member is configured to selectively lock the manipulation member in an ON position according to the switching position of the mode-switching member. The first locking member is allowed to lock the manipulation member in the OFF position both when a hammer mode has been selected and when a drill mode has been selected. The motor is allowed to be driven in a state in which the manipulation member is locked in the ON position by the second locking member only when the hammer mode has been selected.