A chain saw may comprise a braking mechanism; a housing including a first space and a second space in which the braking mechanism is disposed; and an operation member. The housing may include a through hole communicating the second space to outside of the housing. The operation member may be disposed over the second space and the outside of the housing through the through hole. The operation member may be movable between a braking position where the operation member causes the braking mechanism to interrupt rotation of a saw chain and a driving position where the operation member causes the braking mechanism not to interrupt the rotation of the saw chain. The braking mechanism may comprise a connecting member that moves in the second space in conjunction with movement of the operation member. The housing may include an opening communicating the first space to the second space.

A power tool may include an engine, a tool driven for movement by the engine, a brake mechanism coupled to the tool, a charge forming device coupled to the engine and a transmission member operably coupled to the brake mechanism and a throttle valve of the charge forming device. The brake mechanism inhibits movement of the tool in an engaged position of the brake mechanism and permits movement of the tool in a disengaged position of the brake mechanism. The charge forming device is coupled to the engine to provide a combustible fuel and air mixture to the engine, and the throttle valve is movable between a first position and a second position. The transmission member is operably coupled to the brake mechanism and the throttle valve so that the throttle valve is moved away from the first position when the brake mechanism is moved to the engaged position.

A start device is for a chainsaw having a combustion engine. The start device includes an electric motor with a control device, which initiates operation of the electric motor and starts up the combustion engine. The chainsaw has a brake device for bringing the tool to a standstill, wherein the brake device can be operated via an actuation lever. For this purpose, the actuation lever can be moved from a first position (A) into at least one further position (B). The control device is connected to a signal transmitter, which is actuated, and emits a signal to the control device, when the actuation lever is moved from the first position (A) into the further position (B), wherein the signal forms a start signal for initiating operation of the electric motor and for starting up the combustion engine.

Mobile assembly for cutting wood includes a base supported by wheels, and a plurality of posts extending upwards from the base. A frame is removably coupled to a distal post and a proximal post. The frame configured to pivot relative to at least one of the distal and proximal posts when coupled thereto, the frame configured for positioning at different heights along the at least one of the distal and proximal posts. An arm is supported by the frame, the arm configured for sliding about, and parallel to, the frame. The arm includes a chainsaw attached to a distal region of the arm.

Chainsaws having chain tensioning biasing elements are provided. A chainsaw includes a housing comprising a geartrain; a guide bar extending from the housing; a chain moveably coupled around the geartrain and the guide bar; a motive device operatively coupled to the geartrain that selectively drives the geartrain to cause rotational movement of the chain around the guide bar; a tension adjustment assembly configured to selectively move the guide bar relative to the housing to adjust a tension in the chain; and a tension biasing element that continuously imparts an expansive force on the guide bar and/or the chain to oppose a loosening of the tension in the chain.

A handheld engine-driven working machine has an AC power supply, a supplying device which supplies fuel and/or air to an engine, a first path and a second path which are connected to the AC power supply in series and connected to each other in parallel, a handle heater for a handle located in the first path, a device heater for the supplying device located in the second path, and a controller located in the second path. The controller includes a temperature switch for the supplying device and a half-wave blocking element connected to the device heater in series. The temperature switch blocks the second path when a temperature of the temperature switch is higher than a predetermined temperature.

A chainsaw includes a chain, a liquid pump assembly, a motor, and a controller. The chain is used for implementing a cutting operation. The liquid pump assembly includes a liquid pump and a motor. The liquid pump is used for releasing a liquid for lubricating or cooling the chain. The motor is used for at least driving the liquid pump to operate. The controller is electrically connected to at least the motor. The controller is configured to, when the liquid pump is in the jammed state, control the liquid pump assembly to enter a throttling mode in which a supplied amount of the liquid is reduced, and when the liquid pump exits the jammed state, control the liquid pump assembly to exit the throttling mode. Technical solutions provided by the present application can determine and release the jammed state of the chainsaw.

A battery-powered portable cutting tool includes a housing, a cutting element, an electric motor to drive the cutting element to cut, a battery to supply electric current to the motor and a control circuit to control the supply of electric current to the motor from the battery. The control circuit may include a main switch and an auxiliary switch. The control circuit may have an active state in which the main switch allows electric current to flow to the motor and an inactive state in which the main switch does not allow electric current to flow to the motor. The operation of the auxiliary switch causes the control circuit to change between the active and inactive states. The auxiliary switch is arranged to determine whether the tool is in an inappropriate state to be used and, if so, cause the control circuit to change to the inactive state.

A gardening and/or forestry apparatus has a support element. The support element supports an eyelet. The eyelet is configured to incorporate an apparatus securing element. The gardening and/or forestry apparatus also has an element receiving device. The support element and the element receiving device are configured to receive the support element in the element receiving device either in a first rotational position or in a second rotational position differing from the first rotational position and to secure the support element against rotation by form-fitting to the element receiving device.

A work apparatus having a work tool and having a combustion engine which drives the work tool has a start enrichment device for the combustion engine and a braking arrangement for the work tool. The work apparatus has an operating mode selector for actuating the start enrichment device. The start enrichment device actuates the braking arrangement in at least one start position. Low actuating forces and a simple configuration are achieved when the braking arrangement is a differential band brake.