Abstract: The intake device for an engine includes a carburetor section and an air cleaner section. The carburetor section includes a body having an intake passage which has an opening communicating with the air cleaner section and a choke valve being a butterfly valve having a plate-like valve body. The air cleaner section includes an air filter, an air-flow chamber provided between the air filter and the intake passage, and a reverse-flow restriction surface provided within the air-flow chamber. The air cleaner section further includes a plate-like partition extending from a location near an air-cleaner side periphery of the valve body of the choke valve in the full-open position to a location near the reverse-flow restriction surface so as to continue the periphery.

Abstract: A work apparatus having an internal combustion engine includes a body case (100) that houses the engine and other components of the apparatus and a hood (102) that removably covers a top opening of body case (100). The hood (102) has an inclined pin (104) extending aslant downward toward one end of the hood (102) from a portion near the one end. The body case has an inclined bore (106) for receiving the inclined pin (104). A rear end portion of the hood (102) is locked to the body case (100) by a known lock means. The inclined pin (104) wears an elastic tube (112) on its outer circumference.

Abstract: Provided is an exhaust gas combustion device which is capable of early prevention of clogging, and also a power generator including the device. An exhaust gas combustion device of the present invention includes: a DPF; a sensor which measures the pressure of exhaust gas to be introduced into the DPF; a sensor which measures the pressure of exhaust gas purified by the DPF; and a controller which receives outputs from both sensors and calculates a pressure difference. When the pressure difference is equal to or larger than a preset threshold, the heater is supplied with power from a power generating unit to thereby heat exhaust gas. Accordingly, PM accumulated inside the DPF is combusted and removed, preventing excessive clogging of the DPF even during light-load operation.

Abstract: It is intended to effectively prevent blow-by with no need for large changes in typical structures of two-cycle internal combustion engines. A main scavenging passage (24) for supplying air-fuel mixture from a crankcase to a combustion chamber for scavenging purposes has a branch scavenging passage (26) that extends upward aslant toward an intake port (14). The main scavenging passage (24) communicates with a first scavenging port (20) located nearer to an exhaust port (16). The branch scavenging passage (26) communicates with a second scavenging port (22). A mean cross-sectional area of the branch scavenging passage (26) is smaller than that of the main scavenging passage (24). Cross-sectional area of a portion (24b) next to an inlet port (24a) of the main scavenging passage (24) opening to the crankcase is smaller than the sum of cross-sectional areas of the first and second scavenging ports (20, 22).

Abstract: A reverse scavenged two-stroke internal combustion engine is capable of effectively suppressing the short-circuiting of fresh charge (unburnt air-fuel mixture), while at the same time being capable of further improving scavenging efficiency, combustion efficiency, etc. The horizontal sectional shape of at least one pair of scavenging passages is closer to a triangle than a parallelogram along substantially the entire lengths of the at least one pair of scavenging passages, where a cylinder outer circumferential side of the horizontal sectional shape is narrowest and a cylinder bore wall surface side of the horizontal sectional shape is wide. Further, horizontal scavenging angles, which are angles of intersection formed between lines extended towards an intake port from guide wall surfaces that define the scavenging passages, are acute.

Abstract: A backpack strap includes a strap main body, an upper end of which is connected to a backpack frame, a pad attached to the strap main body on a user side, and a contact state holding unit holding an upper end of the pad in contact with the backpack frame. Upper portions of the strap main body and pad are spaced apart from each other by a specified distance. The upper end of the pad has a shape and a strength that is, when contacting the backpack frame, able to prevent the backpack strap from falling sideways. Due to a tensile force of the upper portion of the strap main body and a stiffness of the upper portion of the pad, the upper portion of the pad is held in a projecting state with the upper end of the pad acting as a support point.

Abstract: A three phase inverter-type generator includes an engine, an AC generator driven by the engine, a rectifier for converting the output of the AC generator into a DC voltage, a three phase inverter for converting the output of the rectifier into a three phase AC voltage, a three phase transformer connected to the output side of the three phase inverter, and a filter, whereby the three phase transformer has a primary-side connection and a secondary-side connection having a three phase connection, the secondary-side connection having first through third windings forming a star connection in which one end of each is respectively connected to a neutral point, with each having the same number of windings and a mutual phase difference of 120°.

Abstract: A handheld blower has a body including a combustion engine and a blower section driven by the combustion engine, and a handle coupled to the body. The blower section has an air outlet directed forward with respect to an operator. The handle has a grip portion extending in a front-back direction with respect to the operator, a front arm extending from a front portion of the grip portion to the body, and a rear arm extending from a rear portion of the grip portion to the body. The front arm and the rear arm are more flexible in the front-back direction than in directions perpendicular to the front-back direction.

Abstract: An engine includes a cylinder block, and a piston slidably mounted in a cylinder, with the cylinder block being formed with an exhaust passage leading to a combustion chamber through an exhaust port, a first scavenging port opened to an inner circumferential surface of the cylinder, a first communication passage formed from the first scavenging port in a radial direction of the cylinder, and a first scavenging passage formed with an opening on a bottom surface of the first communication passage, in which a side surface on a far side from the exhaust port forming the communication passage is formed towards the far side from the exhaust port in the combustion chamber, and the opening portion of the first scavenging passage and a landing portion formed in the periphery of the opening portion are formed at a bottom portion of the communication passage.

Abstract: A filler member to be installed in a crankshaft including a crank web includes: an arm member, extending in a diametrical direction of a crank journal, and a weight member extending in a radial direction of the crank journal. The filler member includes: a fitting member, a connecting member mounted on the bodies. The fitting member is fixed to an outer side face of the crank web. The connecting member is mounted on the bodies to stride the arm member on inner side face of the crank web.

Abstract: A blower tube (4) to be connected to a power blower has a tube main body (42) having a distal end portion (42a) diminished in diameter toward its distal end and an attachment (44) to be coupled to the distal end (42a) of the tube main body (42) and including a distal end portion (44a) gradually diminished in diameter toward its distal end. Both these distal end portions (42a, 44a) are each provided three projections at distant position to protrude radially inward toward an axial line of the blower tube (4). The first projections (46) on the tube main body (42) and the second projections (48) on the attachment are positioned offset in phase to align in an alternate order. The blower tube (4) having the projections (46, 48) at the distal end portion can reduce the noise caused by ejection of a high-speed airflow.

Abstract: Object It is intended to prevent intrusion of air-fuel mixture into an air cleaner by blow-back in an air-fuel mixture passage of a stratified-scavenging two-stroke engine. Solution The air cleaner (24) includes a guide member (30). A blow-back flow of air (20) flowing back to the air cleaner (24) through a first air opening (23A) due to blow-back of air is induced to a vicinity of a second air opening (23M) by the guide member (30). A blow-back flow of air-fuel mixture (21) occurring in an air-fuel mixture passage (2) prior to the blow-back phenomenon in an air passage (3) collides the air flow 20 moving toward the vicinity of the second air opening (23M), and retains the air-fuel mixture near the second air opening (23M).

Abstract: A loop scavenged two-stroke internal combustion engine which can effectively restrain blow-by of fresh gas with a relatively simple configuration is provided. A horizontal scavenging angle ?b in at least one spot of a scavenging passage 31L located at one side of the pair of or a plurality of pairs of left and right scavenging passages is made to differ from a horizontal scavenging angle ?a of a scavenging passage 31R located at the other side, and a main flow of a scavenging flow which is blown out from the scavenging passage 31L located at the one side and a main flow of a scavenging flow which is blown out from the scavenging passage 31R which is located at the other side intersect each other or collide with each other in plane view in a region displaced in a lateral direction from a center line C of an opening of an exhaust port 34.

Abstract: In a two-stroke internal combustion engine using air for scavenging its combustion chamber (4), a scavenging passage (6) communicating with a crankcase (2) and a combustion chamber (4) is charged first with rich air-fuel mixture generated by a carburetor, next with lean air-fuel mixture, and next with air through an in-piston passage (36). The lean air-fuel mixture is generated in the in-piston passage 36 by diluting the air-fuel mixture with the air. In each scavenging stroke to scavenge the combustion chamber (4), the combustion chamber (4) is supplied first with the air (40) and next with the lean air-fuel mixture (42) from the scavenging passage (6). The use of the lean-air-fuel mixture (42) next to the air (40) contributes to reduce acceleration failure or engine stop caused by sudden acceleration.

Abstract: In a two-stroke engine (1) according to the present invention, a piston (6) has a communication passage (28) opened to a crank chamber (10). An air intake port (30) is provided on an inner surface (2a) for causing air to flow into the communication passage (28). After a scavenging port (22) is closed by an outer surface (6a) of the piston (6) moving from the bottom dead center to the top dead center, the communication passage (28) is opened in the outer surface (6a) of the piston so as to communicate with the air intake port (30) and the scavenging port (22).

Abstract: There is provided a reverse scavenged two-stroke internal combustion engine that is capable of effectively suppressing the short-circuiting of fresh charge (unburnt air-fuel mixture), while at the same time being capable of further improving scavenging efficiency, combustion efficiency, etc. The horizontal sectional shape of at least one pair of scavenging passages (31, 31 and 32, 32) is closer to a triangle than a parallelogram along substantially the entire lengths of the at least one pair of scavenging passages, where a cylinder outer circumferential side of the horizontal sectional shape is narrowest and a cylinder bore wall surface (10a) side of the horizontal sectional shape is wide. Further, horizontal scavenging angles (?, ?), which are angles of intersection formed between lines (Ea, Ea and Eb, Eb) extended towards an intake port (33) from guide wall surfaces (31c, 31c and 32c, 32c) that define the scavenging passages (31, 31 and 32, 32), are acute.

Abstract: There is provided a loop-scavenged two-stroke internal combustion engine that is capable of effectively suppressing the short-circuiting of fresh charge (unburnt air-fuel mixture), while at the same time being capable of further improving scavenging efficiency, combustion efficiency, etc., as well as of improving the durability and output stability of a cylinder and a piston. One pair or a plurality of pairs of scavenging passages (31, 31 and 32, 32) that adopt a reverse scavenging system are so provided as to communicate a combustion actuating chamber (15) formed above a piston (20) with a crankchamber (18). At least one pair of the scavenging passages (32, 32) comprises, in large part, passage portions with partitions (32k, 32k). A cutout opening or through-hole that serves as a scavenging inlet (32a, 32a), the upper portion or whole of which is of a substantially triangular shape that is narrower towards its upper side, is formed in a lower end portion of at least one of the partitions (32k, 32k).

Abstract: A rotatable rear hand grip (3) is releasably locked at a desired rotational position by operation of a control lever member (4). The power hand tool includes: a tool body (1) including an engine for generating driving power used for performing work; a front hand grip (2) fixed to the tool body; a rear hand grip including: a control lever member coupled to the engine for controlling an output of the engine; a supporting mechanism for supporting the rear hand grip rotationally about an axis (AX) between the tool body and the rear hand grip; a locking mechanism for locking the rear hand grip at one rotational position about the axis in response to the control lever member; and a controlling mechanism (4d) for allowing the control lever member to control the output of the engine after the locking mechanism locks the rear hand grip.

Abstract: An air cleaner is used in a two-stroke internal combustion engine to supply an air-fuel mixture passage and a fresh air passage in a carburetor with air cleaned by an air cleaner element. The air cleaner includes an air cleaner base having an air-fuel mixture opening communicating with the air-fuel mixture passage and a fresh air opening communicating with the fresh air passage, and an air guide member provided at the air-fuel mixture opening. The air guide member is configured to curve near the air-fuel mixture opening and extend from there along the air cleaner base, and has a cross section surrounded by a peripheral wall. The air guide member defines a mixture-use air extension passage for air to be added to prepare an air-fuel mixture air-fuel mixture, which extends from a first clean air intake to the air-fuel mixture opening.

Abstract: Provided is an exhaust gas combustion device which is capable of early prevention of clogging, and also a power generator including the device. An exhaust gas combustion device of the present invention includes: a DPF; a sensor which measures the pressure of exhaust gas to be introduced into the DPF; a sensor which measures the pressure of exhaust gas purified by the DPF; and a controller which receives outputs from both sensors and calculates a pressure difference. When the pressure difference is equal to or larger than a preset threshold, the heater is supplied with power from a power generating unit to thereby heat exhaust gas. Accordingly, PM accumulated inside the DPF is combusted and removed, preventing excessive clogging of the DPF even during light-load operation.