Abstract: A wire throttle adjustment device 1 for performing open-close adjustment of a throttle valve by pull operation of a wire 2. The wire throttle adjustment device 1 includes an operation member 10 connected to an end part 2A of the wire 2 and configured to perform the pull operation of the wire 2. The operation member 10 includes an action part 11 that is elastically deformable by the pull operation of the wire 2 in a fully-opened state of the throttle valve. The action part 11 includes an elastically-deformable elastic arm part 12 configured to swing together with the operation part 15 and extending from the pivotally-supported part 14, and the end part of the wire 14 is connected to a tip part of the elastic arm part 12.

Abstract: An internal combustion engine according to the present invention has an ignition control device. When a rotational speed of the internal combustion engine increases beyond a predetermined rotational over speed, the ignition control device advances an ignition timing of the ignition plug to a first BTDC angle where proper combustion is performed. Further, the ignition control device performs a misfire stroke or strokes of the ignition plug in one rotation or rotations of the crankshaft after the proper combustion is performed by activating the ignition plug at the first BTDC angle.

Abstract: A handheld engine-driven working machine comprises an internal combustion engine with a throttle valve, a throttle adjusting device for adjusting an opening degree of the throttle valve of the internal combustion engine, and a control device provided in the internal combustion engine. The control device is configured to detect a rotational speed and an amount of change in the rotational speed at every at least one rotation of the internal combustion engine. The control device determines that the throttle valve is partially opened when the amount of change in the rotational speed is greater than a predetermined value.

Abstract: To improve responsiveness of fuel supply control, a rotary carburetor 100 has a nozzle 8 including a fuel discharge port 8a and a needle 10 disposed coaxially with the nozzle 8 and disposed with a portion inserted into the nozzle 8. The needle 10 can be displaced relative to the nozzle 8 to change an effective area of the fuel discharge port 8a. The rotary carburetor 100 has an electric motor 14 for displacing the needle 10 along an axis, and a drive mechanism component 12 interposed between the electric motor 14 and the needle 10 and converting a rotational movement of the electric motor into a linear movement.

Abstract: To improve responsiveness of fuel supply control, a rotary carburetor 100 has a nozzle 8 including a fuel discharge port 8a and a needle 10 disposed coaxially with the nozzle 8 and disposed with a portion inserted into the nozzle 8. The needle 10 can be displaced relative to the nozzle 8 to change an effective area of the fuel discharge port 8a. The rotary carburetor 100 has an electric motor 14 for displacing the needle 10 along an axis, and a drive mechanism component 12 interposed between the electric motor 14 and the needle 10 and converting a rotational movement of the electric motor into a linear movement.

Abstract: A suction tube of a stratified scavenging engine that can improve the flexibility in designing the shapes and layouts of an air-fuel mixture passage and an air passage; allow for continuous and smooth changes in the shapes of the cross sections of the air-fuel mixture passage and the air passage from the inlet side toward the outlet side; reduce the number of components; and facilitate attachment and assembly; and that is also advantageous in terms of cost is provided. The suction tube includes an air-fuel mixture passage and an air passage, inlet and outlet sides of the passages being connected to a carburetor and a cylinder, respectively; a cylindrical exterior member that mainly forms an outer perimeter portion of each of the air-fuel mixture passage and the air passage; and an interior member for dividing the inside of the cylindrical exterior member into the air-fuel mixture passage and the air passage.

Abstract: A structure for preventing the falling of a fastening nut of a portable power working machine that can reliably prevent loss of the nut while suppressing the production and component costs, allows for easy operation of attaching a nut anchor member to a cover, and can increase the maintenance property, suppress damage and failures, increase the durability, and reduce the size and weight; and a method for attaching the fastening nut to a cover are provided.

Abstract: An air cleaner includes: a frame member equipped at an intake port of a carburetor and provided with an air inlet port; a filter held by a holding part included in the frame member; a lid member configured to cover a front face of the filter; and a screw with a knob, the screw being configured to connect the frame member and the lid member together. The frame member is provided with an insertion hole, where the screw with the knob is inserted, on the outer side of the holding part. The lid member includes a part to be connected, to which the screw with the knob is connected, the screw being inserted into the insertion hole from a side close to the carburetor. A knob part of the screw with the knob is disposed on the inner side of a circumscribed line between the lid member and the engine.

Abstract: To reduce fatigue in the arm of an operator of a blow operation device driven by an electric motor and to realize a blow operation of blowing and gathering generated compressed air from both the right and left with a small operational burden. A blow operation device includes a backpack type frame, a battery attached to the frame, a blower body having an electric motor to which power is fed from the battery and having an axial fan driven by the electric motor, and a blower tube connected to a blow side of the blower body, the frame including a back contact surface, and the blower body being attached to the frame such that axial directions of the electric motor and the axial fan are along the back contact surface.

Abstract: To optimize fuel supply of an engine with a carburetor during engine operation, a throttle opening degree detection sensor detecting a throttle opening degree and a control unit controlling a valve body variably controlling an opening degree of a fuel discharge part or a fuel supply passage based on a map are included. The map includes a plurality of sections divided based on the throttle opening degree and an opening degree of the valve body set for each section. The opening degree of the valve body set for each section is the opening degree of the valve body at which the engine rotation speed is highest in each section. The control unit controls an electric actuator driving the valve body to achieve the opening degree of the valve body set in a section to which the throttle opening degree detected by the throttle opening degree detection sensor belongs out of the plurality of sections.

Abstract: To improve the effect of preventing contamination of an element in an air cleaner. An air cleaner includes a first inlet (60) through which air is fed to an intake system air passage and a second inlet (62) through which air is fed to an intake system air-fuel mixture passage. An extended passage (72) leads to the second inlet (62), for example. A passage forming member (70, 204) forming the extended passage (72) is shaped to surround a periphery of the first inlet (60). The passage forming member (70, 204) forms a blown-back fuel diffusion preventing region (74) leading to the first inlet (60).

Abstract: The hand-held cutter includes: a cutting blade which is configured to rotate about a rotation shaft to cut a target; a cutter body which rotatably supports the cutting blade; a protection cover which covers a portion of the cutting blade and is rotatable about the rotation shaft; a pressing mechanism which is configured to move toward the protection cover to press a guide plate onto a support plate so as to impose and maintain restrictions on rotation of the protection cover; and a torsion coil spring exerting a biasing force to move the pressing mechanism toward the protection cover. The hand-held cutter is configured such that moving the pressing mechanism, against the biasing force of the torsion coil spring, away from the protection cover removes restrictions on the rotation of the protection cover.

Abstract: A carburetor achieves better emission characteristics while improving a combustion state by increasing a delivery ratio of a stratified scavenging engine and reducing intake resistance. No dividing wall is provided between a throttle valve 204 and a choke valve 242, and a gap 244 between the valves 204 and 242 is opened. Intake air in both of an upper region and a lower region of the choke valve 242 flows into an air-fuel mixture passage 246 in a lower region of the fully-open throttle valve 204. A main nozzle 202 is arranged so as to be inclined toward the throttle valve 204.

Abstract: To provide an exterior body to attach to an engine body, where the exterior body is not limited to where it may be installed, is safe and has excellent dust proofing capability. An engine exterior body (2) is provided with a frame body (20) configured to attach to an engine body (1); a shaft part (21) projecting from the surface of the frame body (20); and a rotator body (22) including a hole part (22a) loosely fitted and retained on the shaft part (21). The rotator body (22) rotates about the shaft part (21) by way of the vibrations transmitted to the shaft part (21) when engine body operates without receiving power from the engine body (1).

Abstract: To balance a “low-temperature scavenging effect” and a “high-temperature scavenging effect.” A scavenging system applicable to a leading-air type two-stroke air-cooled engine has a low-temperature scavenging passage and a high-temperature scavenging passage. The low-temperature scavenging passage has first and second passages and includes scavenging ports at upper end parts thereof. The high-temperature scavenging passage has first and second passages and includes scavenging ports at upper end parts thereof. An air is filled through a piston groove into the passages. The low-temperature scavenging passage has a relatively small capacity. The high-temperature scavenging passage has a relatively large capacity.

Abstract: To allow an intake negative pressure to directly act on a fuel outlet formed on a nozzle tube, and to guide a fuel discharged from the fuel outlet in the nozzle tube to the fuel-air mixture passage. A rotary carburetor (200) has a guide plate member (42) downstream of a fuel outlet (30) located in a through-hole (14). The guide plate member (42) has both side edges (42b) away from an inner wall surface (14a) of the through-hole (14). The through-hole (14) is divided by the guide plate member (42) into a first passage portion (44) and a second passage portion (46). The first passage portion (44) communicates through a piston groove with a scavenging passage of a cylinder. The fuel discharged from the fuel outlet (30) is guided by the guide plate member (42) to the second passage portion (46) and is supplied through the second passage portion (46) to a fuel-air mixture passage (24) of an engine intake system.

Abstract: An engine-driven working machine has an engine unit, a housing, and a vaned rotor. An air passage is defined between a crankcase of the engine unit and a bottom wall of the housing. The air passage has an inlet opening provided near an oil seal on a drive-side shaft, and an outlet opening provided in a magnet-side wall so as to face the vaned rotor. Rotations of the vaned rotor cause airflow from the inlet opening through the air passage to the outlet opening.

Abstract: To improve responsiveness of fuel supply control, a rotary carburetor 100 has a nozzle 8 including a fuel discharge port 8a and a needle 10 disposed coaxially with the nozzle 8 and disposed with a portion inserted into the nozzle 8. The needle 10 can be displaced relative to the nozzle 8 to change an effective area of the fuel discharge port 8a. The rotary carburetor 100 has an electric motor 14 for displacing the needle 10 along an axis, and a drive mechanism component 12 interposed between the electric motor 14 and the needle 10 and converting a rotational movement of the electric motor into a linear movement.

Abstract: An amount of air taken into an air leading type two-stroke engine is increased to enhance an engine output, and gas emission characteristic deterioration caused by blow-back is inhibited. An inhibition member 16 is disposed between a choke valve 4 in a full open position and a throttle valve 6 in a full open position. The inhibition member 16 includes, for example, a mesh member like a metal mesh. Mixed fuel containing oil is supplied to the air-fuel mixture channel 14. Numerous pores of the inhibition member 16 (mesh member) are occluded by a membrane of oil components of the mixed fuel. Consequently, entry of a blow-back flow of an air-fuel mixture from the air-fuel mixture channel 14 into the air channel 12 through the numerous pores of the flow inhibition member 16 (mesh member) can be inhibited.