Abstract: A portable power machine comprises a longitudinally extending rod having an output control and a brake control. From the brake control, a brake action member and a brake gang member control are extended in the opposite directions from each other. A brake gang member and an output gang member have abutting portions to restrict output to the working member by the output control when the working member is in the braked state and to restrict the brake control of the working member when the working member is driven by the output of the motor.

Abstract: A dust collector-equipped power cutter, which is easy to handle in operation and convenient for storage and transportation thereof and is capable of preventing dusty air from flowing back to the cutter portion when a cutting operation is interrupted, includes a main body, a cutter, a dust-sucking fan, and a dust hose assembly. The dust hose assembly includes a first dust hose section and a second dust hose section and a hose connector joining the first hose section and the second hose section. Each of the hose sections has a spiral rib on an outer peripheral surface, and the hose connector has a spiral groove on an inner wall of each end portion, the dust hose section and the hose connector being adapted to be interconnected with each other through a threaded engagement between the spiral rib and the spiral groove. The hose connector is provided with a check valve to prevent back flow when a cutting operation is interrupted or terminated.

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: A method for manufacturing a cylinder for a two-stroke internal combustion engine provided with a pair of hollow scavenging passages, which comprises the steps of casting a raw cylinder body provided with the hollow scavenging passages and forming scavenging ports and/or air-fuel mixture inlet ports communicating respectively with said scavenging passages in the raw cylinder body by means of non-contact machining method.

Abstract: A power cutter is disclosed whose dust suction-discharge fan is driven to rotate at a high speed to thereby attain sufficient dust suction-discharge performance, and which can be constructed relatively compactly in size as a whole at a reduced cost. The power cutter includes two rotating operative components (30, 50) driven by a prime mover (5) and a centrifugal clutch (10) operatively connected to the output shaft (7) of the prime mover (5) for rotationally driving the two rotating operative components (30, 50). The centrifugal clutch (10) includes a clutch drum (11) composed integrally of a small diameter pulley portion (21) and a large diameter pulley portion (22). Belt-type drive trains (15A, 16A and 17A, 18A) transmit the rotational drive force to the rotating operative components (30, 50), respectively.

Abstract: A portable trimmer for cutting weeds comprises a cutter, a driving device for rotationally driving the cutter, a control lever for controlling power of the driving device, a braking device for stopping rotation of the cutter, and an interlocking device operatively connected with the control lever and the braking device. The braking device has a wedge shaped brake shoe that is connected with the interlocking device and has an inclined upper surface inclined downwardly from a rotationally retarded side toward a rotationally advanced side of the cutter, a housing enclosing the brake shoe and having an inclined guide surface opposite to the inclined upper surface of the brake shoe, and a pressing device provided between the brake shoe and the housing and for causing an initial movement of the brake shoe toward a cutter surface of the cutter.

Abstract: A portable trimmer has a supporting tube with a forward end on which is mounted a cutting device. The cutting device has a case with a first hole for receiving a stick, and also contains a rotatable shaft with a threaded end. A seating member that is rotatable with the shaft has a second hole that can be aligned with the case's first hole. A rotatable cutter is removably mounted on the rotatable shaft, fixed to against the seating member by a nut that engages the shaft's threads. The stick is inserted into the first hole in the case and the second hole in the rotatable seating member, to prevent rotation of the seating member during assembly and disassembly. The cutting device retains the stick in the first and second holes even when the cutting device is upside down. This retention is accomplished, either by a biasing member that biases the stick in a direction perpendicular to the axis of the first hole, or by an elastic member that frictionally engages the stick in the hole.

Abstract: A core for use in a die casting process has a wood fiber material as a main ingredient. The core can be disintegrated by exerting an external force subsequent to the die casting process. The core can also be disintegrated by applying a softening agent to soften it subsequent to the die casting process. Further, the core can be made up of a stack of paper layers that are peelably removable from each other.

Abstract: A handling device for setting the opening degree of the throttle valve to a desired degree even under conditions where the throttle lever is rotated to a full extent, and capable of immediately returning the throttle lever to a minimum opening degree (idling opening). The handling device has a main lever connected with one end portion of a cable and designed to pull the cable connected via the other end portion thereof with an actuating member, a movable pulley around which a portion of the cable in the vicinity of the one end portion is wound as a turn-around point, and a position adjustment mechanism comprising a sub-lever. The sub-lever is designed to move the movable pulley to a desired holding position so as to adjust a distance of pulling the cable.

Abstract: A hand-held power working machine which makes it possible to enlarge the area of the front handle portion which is available for gripping, to enhance the rigidity of the hand protector, and to facilitate the mounting of the front handle and hand protector. This hand-held power working machine comprises a front handle portion and a hand protector, and is characterized in that the hand protector is constituted by a rear protector body having an inverted U-shaped cross-section formed with an upper plate and right and left side plates, and by a front protector body disposed in front of and extending outwardly from the rear protector body and forming a sectorial shape, and in that the front handle portion is integrally formed with the side plates of the rear protector body.

Abstract: A power cutter is disclosed which is capable of selectively changing the discharge direction of dust discharged from a dust discharge port of a dust suction-discharge fan and, hence, which is capable of optimally adjusting the dust discharge direction according to the operational condition or operational position of the power cutter. An elbow-shaped auxiliary discharge pipe is coupled to the dust discharge port of the dust suction-discharge fan in such a manner that it can be turned and kept at any turned position. In addition, a belt tensioning clutch is provided to permit selective connection and disconnection of the belt drive transmission between the power source and the dust section-discharge fan. This permits fan operation to be interrupted when not needed.

Abstract: A hand lever device is disclosed which has excellent operability and is convenient and comfortable for an operator when an operating portion of a main lever and a grip are gripped together to carry out operation, and which enables a Bowden cable and the like to easily be introduced into the grip. The hand lever device comprises a grip and a lever having a pivotally movable operating portion. The grip has a protuberant portion provided with a lever rest of a depressed configuration for ensconcing the operating portion therein. Preferably, the protuberant portion of the grip is provided with a lever rest in a center portion thereof in cross-section and also provided with a through hole extending through sides of the lever rest for leading and holding control line members such as a cable and a cord.

Abstract: A portable air-blowing working machine includes a prime mover and an air-blowing system. The air-blowing system incorporates first-stage and second-stage centrifugal air-blowing sections, which are rotatably driven by an output shaft of a prime mover and are interconnected by an air-blowing passage for delivering air discharged from the first-stage air-blowing section to the intake of the second-stage air-blowing section. The first-stage air-blowing section and the second-stage air-blowing section share a common unitary double fan, which includes fore and rear centrifuged fan blades mounted on the fore (first stage) and rear (second stage) faces of a main disk plate integrally mounted on the output shaft of the prime mover.

Abstract: The present invention provides a small and light four-stroke cycle internal combustion engine applicable to a compact power working machine. A cylinder head is provided with an ignition plug and an exhaust port with an exhaust valve. A crankcase is fixed to the bottom of a cylinder block are to form a closed crank chamber. On the cylinder block formed are a first port and a second port which are open to a combustion chamber and are opened and closed by a piston, with the second port being communicated with the crank chamber through a communicating passage, the first port being connected to a carburetor, and an air-fuel mixture mixed with lubricating oil being supplied from the carburetor through this first port to the crank chamber.

Abstract: A hand-held power working machine which is capable of reducing the weight of the clipper blades, capable of being suitably heat-treated in the manufacture thereof, and capable of minimizing the stress concentration at the slot portions during the operation thereof. The clipper blades comprise a large number of cutting edges, and a large number of slots formed along a full length of each of the clipper blades; wherein the pitch of array of the cutting edges is substantially the same as the pitch of array of the slots.

Abstract: A cap assembly for sealing a spout of a container, the cap assembly comprising:a) a cap including:1) a top wall formed with a plurality of vertical holes; and2) a skirt that is suspended from the top wall so that the vertical holes in the top wall form respective shelves extending laterally near a boundary region between the top wall and the skirt; andb) a gasket that is mounted on an inner side of the top wall, the gasket having:1) a body adapted to seal the spout of the container; and2) a plurality of ears, the ears extending laterally outward from the body, spaced from each other along a circumference of the body, corresponding to the respective vertical holes in the top wall, and supported by the respective shelves.

Abstract: A power source and a human contacting portion of a portable power tool, with a vibration-proof member and a spacer placed between them, are tightened by fastening and connecting means in the direction approaching each other. The spacer serves to limit compressive power of the vibration proof member which acts between the power source and human contacting portion within effective vibration-proof range of the vibration-proof member by utilizing the fastening and connecting means, This does not cause the vibration absorbing effect of the vibration-proof member to be lost. In addition, there is no need to check the fastening degree achieved by the fastening and connecting means, thus allowing easy attachment of the vibration-proof member thereto. Alternatively, vibration-proof members may be placed between the power source side and the working member side without spacers if the vibration proof members support the power source apart from the working member.

Abstract: A four-stroke internal combustion engine in accordance with the present invention comprises a piston, a valve chamber, a crankcase, an oil chamber separated from the crankcase, and an oil mist feeding passage extending from the oil chamber to the crank case via the valve chamber for supplying oil mist in the oil chamber. The oil mist feeding passage has a first passage extending from the oil chamber to the valve chamber, a second passage extending from the valve chamber to the crankcase, and a third passage extending from the crankcase to the first passage. The first passage has a first opening directed toward the oil chamber. The second passage has a second opening directed toward the crankcase located at a point where it can be closed by the piston when it travels downwardly. The third passage has a third opening directed toward the crankcase located at a point below a bottom dead center of the piston.

Abstract: A braking device for a power working machine, which is capable of immediately stopping the movement of the working portion when an internal combustion engine is shifted to an idling state, includes a transmission shaft, a brake drum fixed to the transmission shaft, and a brake band wound around the brake drum. The brake band is formed of a leaf spring material band, which is biased to shrink the diameter thereof, one end of which is pivotally supported on a supporting pin, and the other end of which is formed into a bent free end.

Abstract: An OHC type four-stroke cycle internal combustion engine comprises a crankshaft, a camshaft, a camshaft bearing for supporting the camshaft, a cam chamber for accommodating the camshaft, a gear train for transmitting the rotation of the crankshaft to the camshaft, a gear chamber for accommodating the gear train, a crankcase communicating with the cam chamber via the gear chamber, an inlet port, and a piston. The camshaft has a camshaft through hole which communicates with the cam chamber at one end and opens toward its circumferential surface supported by the camshaft bearing at the other end. The camshaft bearing has a camshaft bearing through hole which communicates with the camshaft through hole at one end and communicates with the inlet port at the other end.