An electric power tool includes a motor, a driving side member, and a driven side member. The driving side member and the driven side member have mutually opposed surfaces. A plurality of cam teeth are respectively disposed on concentric circles on the opposed surfaces. The plurality of cam teeth have meshing surfaces inclined at predetermined lead angles. A torque limiter is formed to disengage the engagement of the meshing surfaces of the cam teeth by moving the one member in a separation direction from the other member when load of the driven side member increases. The respective cam teeth are formed such that the lead angles of the meshing surfaces are different between a forward rotation side and a reverse rotation side. A transmission torque transmitted from the driving side member to the driven side member is equal between the forward rotation and the reverse rotation.

A power tool having a hammer mechanism includes a tool body defining the driving axis, a motor housed in the tool body, an elongate handle connected to the tool body in a cantilever manner and extending in a direction intersecting the driving axis, and at least one biasing member disposed between the tool body and the handle. The motor has a motor shaft that is rotatable around an axis parallel to the driving axis. The handle includes a first end portion connected to the tool body to be pivotable around a pivot axis relative to the tool body, a free end, and a grip part disposed between the first end portion and a free end of the handle. The at least one biasing member is configured to pivotally bias the tool body and the handle such that the grip part and the tool body move away from each other.

The present disclosure provides a side handle assembly for a power tool. The side handle assembly includes a clamp configured to secure the side handle assembly to the power tool, the clamp coaxially aligned with a working axis of the power tool, and a handle coupled to the clamp. The handle includes a base coupled to the clamp, a first grip portion coupled to the base, a second grip portion coupled to the base and movable relative to the first grip portion in a direction parallel to the working axis, and a damping element located between the first grip portion and the second grip portion to attenuate vibration from the power tool along the working axis.

A power tool includes a tool body, a motor, a handle, at least one biasing member, and at least one guide part. The handle is connected to the tool body to be pivotable and to be movable in at least a front-rear direction relative to the tool body. The handle includes a cover part covering a portion of the tool body and a grip part extending in a cantilever manner from the cover part. The at least one biasing member biases the tool body and the handle away from each other in the front-rear direction. The at least one guide part includes a first portion disposed on a portion of the tool body covered by the cover part, and a second portion disposed on the cover part of the handle and connected to the first portion to be movable in at least the front-rear direction relative to the first portion.

An objective is to provide a technique to securely protect the striking tool even when the striking tool inadvertently falls down. A striking tool including a rotating shaft relatively rotatably connect a main body with a handle, a first elastic member reducing transmitting of vibration from the main body to the handle in a case that the handle relatively rotates to the main body, wherein the handle includes a battery mounting portion to which battery to drive the motor is attachable and the handle is arranged to relatively move to the main body across the rotating shaft, and an adjuster such that the relative movement amount of the handle to the main body in a predetermined direction is adjusted to be larger than the relative movement amount in a direction other than the predetermined direction.

An apparatus for punching an anchor bolt insertion hole is disclosed. The apparatus enables punching work for forming the anchor bolt insertion hole, of which the bottom side is wider than an inlet, on a panel surface for constructing a concrete structure to be performed regardless of the skill of a worker. During operation, the apparatus provides the movement direction of a hammer drill into the vertical direction and the inclination direction so as to enable precise punching work, and doubly arranges springs, which are elastic devices for adjusting the movement range of the hammer drill, so as to uniformly maintain the angle and size for cutting a wall such that a cross-sectional diameter is large at a portion adjacent to the bottom of the anchor bolt insertion hole.

A pneumatic tool structure contains an air intake head, a slidable sleeve, a drive unit, a piston, an operation element, a resilient element, a first isolation ring, and a second isolation ring. The air intake head includes a press lever, an air channel, and a connection portion. The connection portion has a first coupling orifice. The slidable sleeve includes a shoulder. The drive unit includes a body, a recessed portion having a defining fringe, a screw bolt, and a chamber. An air discharge conduit is defined between the slidable sleeve and the body. The first segment has a second coupling orifice. The resilient element includes a through hole. The first isolation ring includes a first rim, a second rim, multiple first discharging grooves, and multiple first contact portions. The second isolation ring includes a third rim, a fourth rim, multiple second discharging grooves, and multiple second contact portions.

A vibration reducing structure of pneumatic hammer includes a handle having a concave room with a bottom wall and an air inlet channel communicating with the concave room. A control valve is disposed in the air inlet channel. A movable inner tube shell is accommodated in an outer tube shell coupled with the concave room and extends a rear bucket portion into the concave room. A movable hammer member, an air inlet valve for activating the hammer member and a hole communicating the air inlet channel to the air inlet valve are disposed in the inner tube shell. An air room is formed between the bottom wall and an end wall of the inner tube shell. A communicating channel communicates the air inlet channel to the air room for air with high pressure entering the air room.

A power tool includes a tool body, a motor, a handle, at least one biasing member, and at least one guide part. The handle is connected to the tool body to be pivotable and to be movable in at least a front-rear direction relative to the tool body. The handle includes a cover part covering a portion of the tool body and a grip part extending in a cantilever manner from the cover part. The at least one biasing member biases the tool body and the handle away from each other in the front-rear direction. The at least one guide part includes a first portion disposed on a portion of the tool body covered by the cover part, and a second portion disposed on the cover part of the handle and connected to the first portion to be movable in at least the front-rear direction relative to the first portion.

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.