An electric tool grinding machine includes an electric motor, an airflow generating member, and a casing. The casing includes a hollow shell, a motor housing located in the hollow shell, two partitioning plates located between a side wall of the motor housing and the hollow shell, at least one air outlet facing the airflow generating member, a first air inlet formed on the hollow shell, and at least one second air inlet formed on the hollow shell and spaced apart from the first air inlet. When the airflow generating member is activated, the first air inlet generates a pressure difference in the hollow shell near an air inlet portion of the motor housing to cause air to be drawn into the second air inlet.

An electric tool grinding machine includes an electric motor, an airflow generating member, and a casing. The casing includes a hollow shell, a motor housing located in the hollow shell, two partitioning plates located between a side wall of the motor housing and the hollow shell, at least one air outlet facing the airflow generating member, a first air inlet formed on the hollow shell, and at least one second air inlet formed on the hollow shell and spaced apart from the first air inlet. When the airflow generating member is activated, the first air inlet generates a pressure difference in the hollow shell near an air inlet portion of the motor housing to cause air to be drawn into the second air inlet.

The disclosure discloses an electric power tool. The electric power tool may include a motor, a power transmission mechanism connected to the motor, a housing that houses the motor and the power transmission mechanism, an end tool holder to which an end tool is configured to be attached and from which the end tool is configured to be detached, and connected to the power transmission mechanism, and a handle attached to the housing. The electric power tool may be configured to prohibit rotation of the motor when a user is not gripping the handle.

An electric power tool includes an output shaft, drivable by an associated drive motor, and a brake apparatus for braking the output shaft rotating in the unpowered state of the associated drive motor. The output shaft is mounted in a rotatable manner in an associated housing and the brake apparatus has a magnetic-field brake unit with at least one first and one second brake element. The first brake element is arranged radially with respect to the output shaft in a rotationally fixed manner in the associated housing and includes at least one first and one second magnetic pole configured to generate a magnetic field that alternates in the circumferential direction of the output shaft. The second brake element is magnetically conductive and rotationally connected to the output shaft via an activatable coupling device.

An electric power tool includes an output shaft, drivable by an associated drive motor, and a brake apparatus for braking the output shaft rotating in the unpowered state of the associated drive motor. The output shaft is mounted in a rotatable manner in an associated housing and the brake apparatus has a magnetic-field brake unit with at least one first and one second brake element. The first brake element is arranged radially with respect to the output shaft in a rotationally fixed manner in the associated housing and includes at least one first and one second magnetic pole configured to generate a magnetic field that alternates in the circumferential direction of the output shaft. The second brake element is magnetically conductive and rotationally connected to the output shaft via an activatable coupling device.

A power tool which brakes a motor without turning off a trigger switch when a trouble occurs in the motor is provided. The power tool (10) comprises: a motor (20) that rotates by supply of electricity from a power source (PS); a controller (38) for controlling the rotation of the motor; a switch (12) for switching on and off of power supply from the power source to the motor manually; first braking means (23) for braking the motor when the switch (12) is switched from on to off; and second braking means (23, 45) for braking the motor (20) on the basis of a prescribed signal from the controller when the switch (12) is in an on state.

A handheld work apparatus has a tool and a brake assembly for the tool. The brake assembly has an actuating element which acts on a brake element of the brake assembly. The actuating element is movable between a fixed position wherein the tool is not braked, and a released position, wherein the brake element brakes the tool. To fix the actuating element in the fixed position, an electromagnet is provided. The electromagnet interacts with an anchor on the actuating element. The anchor is mounted via a pivot joint on an anchor pin to be pivotable about a pivot axis. A guide includes a guide part connected to the anchor and a guide part connected to the yoke, wherein, in the fixed position of the actuating element, the guide parts guide the anchor relative to the yoke in a transverse direction of an outrigger of the apparatus.

A pneumatic power tool includes: a housing with a pressure air inlet passage, a rotation motor, a working implement carrying output shaft, and an over-speed safety device including: a valve element located in the inlet passage and shiftable between open and closed positions, a motor speed responsive actuating mechanism which can shift the valve element from an open to a closed position as motor speed reaches an accepted maximum limit, and a retaining unit which maintains the valve element in an open position at normal motor speed levels and releases it toward the closed position when actuated by the actuating mechanism. The retaining unit includes: a latch spindle having varying width in an axial direction and coupled to the actuating mechanism for displacement between valve element locking and releasing positions at the maximum speed limit, and a support surface and axially adjacently located one or more waist portions.

A pneumatic power tool includes: a housing with a pressure air inlet passage, a rotation motor, a working implement carrying output shaft, and an over-speed safety device including: a valve element located in the inlet passage and shiftable between open and closed positions, a motor speed responsive actuating mechanism which can shift the valve element from an open to a closed position as motor speed reaches an accepted maximum limit, and a retaining unit which maintains the valve element in an open position at normal motor speed levels and releases it toward the closed position when actuated by the actuating mechanism. The retaining unit includes: a latch spindle having varying width in an axial direction and coupled to the actuating mechanism for displacement between valve element locking and releasing positions at the maximum speed limit, and a support surface and axially adjacently located one or more waist portions.

An electric power tool includes an output shaft, drivable by an associated drive motor, and a brake apparatus for braking the output shaft rotating in the unpowered state of the associated drive motor. The output shaft is mounted in a rotatable manner in an associated housing and the brake apparatus has a magnetic-field brake unit with at least one first and one second brake element. The first brake element is arranged radially with respect to the output shaft in a rotationally fixed manner in the associated housing and includes at least one first and one second magnetic pole configured to generate a magnetic field that alternates in the circumferential direction of the output shaft. The second brake element is magnetically conductive and rotationally connected to the output shaft via an activatable coupling device.