A chainsaw which has a motorized chain that is suitable for sawing and trimming objects. The chainsaw includes a motor housing comprising a side portion, a chain, a guide bar, an electric motor, and a front handle. Safer handling and ergonomics is achieved by the motor housing comprising a concave contour on part of the surface of the side portion.

A handheld trenching apparatus and method of forming a trench in ground using the apparatus. The apparatus has a frame, a cutting head, and a drive. The cutting head has a ground penetrating portion with a plurality of cutting members that are caused to be moved in a controlled path by the drive. The frame has an elongate frame part with the cutting head at one frame part end. The frame further has at least one graspable region spaced lengthwise of the elongate frame part from the first elongate frame part end. The ground penetrating portion is directed into the ground and while engaging the at least one graspable region the ground penetrating portion is moved in a trench forming direction as the drive is operated to thereby form a trench.

A transmission shaft assembly includes a connecting tube extended along a central axis, a transmission shaft being a rigid shaft made of metal material, which is extended along the central axis and disposed in the connecting tube, a first limiting element disposed on an end of the connecting tube and formed with a first hole allowing the transmission shaft to pass there through, a second limiting element disposed on the other end of the connecting tube and formed with a second hole allowing the transmission shaft to pass there through, and a bushing. The bushing includes a main body formed with a channel extended along the central axis and several projecting parts disposed on the periphery of the main body. The bushing is located in the connecting tube and disposed between the first limiting element and the second limiting element. The transmission shaft passes through the first hole, the channel, and the second hole successively.

A method is provided for type-specific operating of an electric drive unit, wherein the drive unit is configured for coupling and driving a tool unit selected from a set of different types of tool units. The set includes at least one rotatory tool unit and at least one non-rotatory tool unit. The method includes: driving of a coupled tool unit by the drive unit; identifying operating data of the drive unit during the driving procedure; determining, based on the identified operating data, whether the coupled tool unit is a rotatory tool unit or a non-rotatory tool unit; and controlling the drive unit in a rotation control mode if the coupled tool unit is determined to be a rotatory tool unit, or in a non-rotation control mode if the coupled tool unit is determined to be a non-rotatory tool unit.

A handheld work apparatus includes a first assembly, a second assembly and an anti-vibration unit which includes a coil spring. A first end of the coil spring forms a fastening eyelet fixed to the first assembly by an attachment screw which extends through the fastening eyelet and the head thereof projects into the coil spring. A second end of the coil spring is screwed onto a connecting piece of the second assembly which has an opening extending through the connecting piece and through which an engagement contour in the head of the attachment screw is accessible for a tool. When the work apparatus is in a non-loaded state, the distance (f) between the fastening eyelet and a front end of the connecting piece is the length (g) of the attachment screw. The distance (p) of the above support surface from the front end of the connecting piece is the length (g).

According to examples, a modular power tool may include a motor housing including an electric motor, a drive member connected to the electric motor, the drive member being connected to a drive coupler, an extension pole including an input shaft having a first end connector and a second end connector, in which the first end connector is configured to mate with the drive coupler, and an attachment component having an attachment connector and a working implement, in which the attachment component is configured to mate with either of the drive coupler and the second end connector.

A positioning system, attachable to a vehicle for remote operation of the chain saw by a user sitting in the vehicle. A shock absorber indicator functions to tell the user when the weight on the limb is appropriate to engage the saw, and additionally cushions the drop when the saw cuts through the limb.

A conveying device includes: a main movement body; a main conveying mechanism that conveys the main movement body; and a controlling device that controls operation of the main conveying mechanism including a plurality of winches attached to the main movement body and multiple cables one wound around each winch; each winch includes a cylindrical drum rotatable about an axis line thereof and driving device that rotates the drum, and is wound around corresponding one of the drums of the respective corresponding winches helically in an axis direction of the drums multiple times, and have distal ends supported by supporting bodies corresponding to the respective winches; and the controlling device conveys the main movement body to an arbitrary position on a conveying path between the supporting bodies corresponding to the respective winches by controlling operation of a driving device of each winch disposed on the main movement body.

A cutting tool includes: an electric motor with a stator having multiple windings and a rotor; a driver circuit electrically connected to the electric motor to drive the electric motor to run; and a controller configured to estimate the angular position of the rotor based on a working parameter of the electric motor and output a drive signal to the driver circuit based on the angular position of the rotor to control the rotation of the electric motor. At a start stage, the controller is configured to: when an abnormal start of the electric motor is detected, output a first control instruction to control the electric motor to restart, where the first control instruction includes at least the instruction to input a high-frequency signal into the driver circuit so as to acquire the angular position of the rotor.

A power tool includes an elongated shaft forming a handle and a tool head located at one end of the handle. The tool head includes a working element and a driven shaft configured to drive the working element. A powerhead located at an opposite end of the handle and includes an input shaft. A driveshaft is coupled between the tool head and the powerhead. The driveshaft has a first driveshaft portion rotatably driven by the input shaft and a second driveshaft portion coupled to the first driveshaft portion and the driven shaft. The second driveshaft portion is driven by the first driveshaft portion to transfer torque from the powerhead to the working element. One of the first driveshaft portion or the second driveshaft portion is constructed of a non-conductive material or both of the first driveshaft portion and the second driveshaft portion are constructed of a non-conductive material.