Abstract: A recoil starter for a backpack type power working machine, which is capable of easily performing the starting operation of an internal combustion engine with the working machine being carried on the operator's back. In this recoil starter, the recoil rope and the recoil handle are disposed so as to be pulled down obliquely forward at an angle of 100° to 150° to the horizontal plane. The recoil handle is formed into a T-shaped configuration in side view, which comprises the grip portion and a laterally extended stopper portion which is formed on a distal end of the grip portion.

Abstract: A recoil starter for a backpack type power working machine, which is capable of easily performing the starting operation of an internal combustion engine with the working machine being carried on the operator's back. In this recoil starter, the recoil rope and the recoil handle are disposed so as to be pulled down obliquely forward at an angle of 100° to 150° to the horizontal plane. The recoil handle is formed into a T-shaped configuration in side view, which comprises the grip portion and a laterally extended stopper portion which is formed on a distal end of the grip portion.

Abstract: A backpack type power working machine includes a movable stopper for restricting the turning angle of an internal combustion engine unit which is supported on a backpack frame so that it turns about a longitudinal axis. As a result, the turning angle restriction of the internal combustion engine unit can be released by just moving the movable stopper, whereby a job efficiency can be improved.

Abstract: To provide a vibration-damping assembly sufficiently functions in wide range of vibration with improved durability, and effective spring constant thereof can easily be changed as occasion demands. The vibration-damping assembly comprises a leaf spring (20) and a vibration-damping rubber (23) which are connected to each other in series, and a base end portion of the leaf spring (20) is secured to stand portions (3B, 3C) of a support (3), and another end of the vibration-damping rubber (23), which is not connected to the leaf spring (20), is connected to the prime mover (10).

Abstract: A disengagement-preventing mechanism for a vibration isolator is interposed between an attachment sleeve portion of prime mover and an operating rod in a bush cutter. The disengagement-preventing mechanism includes an attachment sleeve portion, an attachment member which is to be inserted in and engaged with the attachment sleeve portion, and a C-shaped disengagement-preventing clip. The attachment sleeve portion is provided, at a peripheral wall thereof, with a clip-introducing slit extending in a circumferential direction of the attachment sleeve portion and with a clip-holding slit located so as to face the clip-introducing slit. The disengagement-preventing clip is adapted to be introduced from outside into the clip-introducing slit and brought into contact with an external end face of the attachment member. The clip is also adapted to be engaged, by way of the distal end portion thereof, with the clip-holding slit.

Abstract: A fuel inlet is disposed on the upper part of a fuel tank which is protruded upwardly and a connecting portion of a return pipe is located which is also protruded on the upper part of the fuel tank being separated from the fuel inlet and an air reservoir is disposed within the connecting portion of the return pipe. When fuel is poured through the fuel inlet, fuel will not go into the air reservoir. Therefore, vibrations given to the fuel tank does not cause the return pipe blocked at its lower end, allowing overflown fuel to be returned smoothly back to the fuel tank.

Abstract: A portable electric working machine of the present invention includes a motor case portion housing an electric motor, a working portion driven by the electric motor, a handle connected to the motor case portion or the working portion and a power source switch disposed within a grip portion of the handle. Electric power is supplied to the electric motor through the power source switch. A spark-preventing capacitor accommodated within the motor case portion is interposed between a pair of terminals of the electric motor. The portable electric working machine of the present invention does not require a large-sized grip portion of a handle, and can prevent a locking of contacts of a power source switch due to contact transition by preventing sparking between the contacts so that a small-sized microswitch can be used.

Abstract: A portable work machine equipped with an internal combustion engine. A starting pressure reducing device is mounted on a cylinder of the engine for reducing, at starting of the engine, pressure within a combustion chamber defined in the cylinder. A hole is formed at a portion of an engine cover which is within reach of a finger of a hand holding a handle, and is closed by a flexible cap. An actuating portion of the starting pressure reducing device is disposed inside the cap.

Abstract: An air-fuel mixture intake pipe for an internal combustion engine, wherein a plurality of projection rows each composed of a plurality of projections spaced from each other on an inner wall of the intake pipe and arranged in a circumferential direction are spaced from each other rows in a longitudinal direction of the intake pipe, and a space of each adjacent projections is defined by a longitudinal groove.