Abstract: A two-stroke cycle combustion engine of an air scavenging type includes one or more scavenging passages (13, 14) for communicating a crank chamber (2a) and a combustion chamber (1a) with each other, an air passage (10) for supplying an air (A), an introducing passages (16) for introducing the air (A) from the air passage (10) into an upper portion of each scavenging passage (13, 14) from a direction radially outwardly of a cylinder block (1), and a covering member (21) for covering the introducing passage (16) from an outer side. The covering member (21), the upper portion of each scavenging passage (13, 14) and a part of the introducing passage (16) are formed integrally with each other by a scavenging block (20).

Abstract: A two-stroke cycle engine for introducing a air/fuel mixture and an air from a scavenging passage into a combustion chamber includes a valve body for adjusting the opening of an air supply passage, through which the air is supplied to the scavenging passage, and a second opening of a air/fuel mixture supply passage, through which the air/fuel mixture is supplied to the scavenging passage, a check valve for preventing the air within the air supply passage from flowing in a reverse direction, and a delay member projecting into the air supply passage on an upstream side of the check valve for delaying the timing at which the air reaches from the valve body to the air scavenging passage.

Abstract: A two-stroke cycle combustion engine of an air scavenging type includes one or more scavenging passages (13, 14) for communicating a crank chamber (2a) and a combustion chamber (1a) with each other, an air passage (10) for supplying an air (A), an introducing passages (16) for introducing the air (A) from the air passage (10) into an upper portion of each scavenging passage (13, 14) from a direction radially outwardly of a cylinder block (1), and a covering member (21) for covering the introducing passage (16) from an outer side. The covering member (21), the upper portion of each scavenging passage (13, 14) and a part of the introducing passage (16) are formed integrally with each other by a scavenging block (20).

Abstract: To provide a four-cycle combustion engine wherein the air-fuel mixture can be smoothly passed at all times by the utilization of the reciprocating motion of the piston to effectively lubricate the valve operating mechanism and the cranking mechanism and also to allow the air-fuel mixture to be supplied into the combustion chamber with a high suction efficiency. By utilization of the reciprocating motion of the piston (9), a portion of the air-fuel mixture (M) fed from the intake passage (33) is circulated through a circulating passage made up of the valve chamber (18), the first passage (24), the crankcase chamber (7) and the second passage (41).

Abstract: To provide a four-cycle combustion engine wherein the air-fuel mixture can be smoothly passed at all times by the utilization of the reciprocating motion of the piston to effectively lubricate the valve operating mechanism and the cranking mechanism and also to allow the air-fuel mixture to be supplied into the combustion chamber with a high suction efficiency, the four-cycle combustion engine includes a valve operating mechanism (30) including a valve drive unit (23) for driving intake and exhaust valves (19, 20) and a drive transmitting unit (29) for transmitting a rotary drive of a crankshaft (8) to the valve drive unit (23), a valve chamber (18) accommodating the valve drive unit (23) and communicated with an intake port (40), an intake passage (33) through which an air-fuel mixture (M) containing a lubricant oil is introduced into the valve chamber (18), a first passage (24) accommodating the drive transmitting unit (29) and connecting between the valve chamber (18) and the crankcase chamber (7), and a s

Abstract: A hand-held edger capable of suppressing wear of a cover without an increase in the number of parts. The hand-held edger comprises a main rod supported by an operator's hand; a gear case supported at one end portion of the main rod; a rotating blade connected to a gear in the gear case; a power unit mounted to the other end portion of the main rod, for driving the rotating blade via the gear in the gear case; a resin-made cover attached to a flange of the gear case, for covering the rotating blade; and a wheel supported by the cover, and an outer periphery of the flange is coplanar with the periphery of at least the lowermost portion of the cover or diametrically outwardly protruded therefrom.

Abstract: A cutting blade cover for a brush cutter comprises a central portion (50), a first blade accommodating portion (28), a second blade accommodating portion (29), and a third blade accommodating portion (30). The first, second, and third blade accommodating portions (28, 29, 30) are provided radially from the central portion (50). The first blade accommodating portion (28) includes a first concave portion (31). The second blade accommodating portion (29) includes a second concave portion (36). The third blade accommodating portion (30) includes a third concave portion (40). The first concave portion 31 has an inner shape conforming to an outer shape of the first blade (17) to cover an outer periphery of the first blade (17). The second concave portion (36) has an inner shape conforming to an outer shape of the second blade (18) to cover an outer periphery of the second blade (18).

Abstract: A cutting blade cover(10) is used for protecting a cutting blade(11) having a shank member(16) connected to a driving unit of a reaper and a plate-shaped blade member(17) continuous with the shank member(16) and provided with a cutting portion(18) at a tip portion thereof that is orthogonal to the shank member(16). The cutting blade cover(10) comprises a bag-shaped accommodating portion(24) for accommodating the cutting portion(18) provided at the tip portion of the plate-shaped blade member(17) and a shank retaining portion(25) for retaining the shank member(16).

Abstract: In a conventional impact generator, a grease receives centrifugal force by the rotation of a rotary member, thereby keeping away from surfaces of the rotary member and a weight. Consequently, insufficient lubrication is caused between the weight and a member (for example, a tappet and the like) which comes in contact with the weight. An impact generator D comprises an impregnating member 60 capable of impregnating the grease. The impregnating member 60 is extended from a vicinity of an inner peripheral wall surface 59 of a chamber E1 for accommodating a rotary member 10 and a weight 30 to a position where the impregnating member 60 comes in contact with the weight 30 performing a circular motion.

Abstract: In a conventional impact generator, a great shock is generated when a weight collides with a rotary member, and a rotary shaft of the rotary member and a bearing supporting the rotary shaft receive the great shock. Therefore, it is necessary to employ a bearing having a great load capacity. Furthermore, great vibrations and noises are also generated in the impact generator. A rotary member (10) is rotatably supported by rotary shafts (11) and (12). A weight (30) is movably held by the rotary member (10). A shock absorber (40) for absorbing, by elastic force, a shock generated between the weight (30) and the rotary member (10) is provided between the weight (30) and the rotary member (10).

Abstract: Disclosed is a hand-held edger capable of suppressing wear of a cover without an increase in the number of parts. The hand-held edger comprises: a main rod supported by an operator's hand; a gear case supported at one end portion of the main rod; a rotating blade connected to a gear in the gear case; a power unit mounted to the other end portion of the main rod, for driving the rotating blade via the gear in the gear case; a resin-made cover attached to a flange of the gear case, for covering the rotating blade; and a wheel supported by the cover, and an outer periphery of the flange is coplanar with the periphery of at least the lowermost portion of the cover or diametrically outwardly protruded therefrom.

Abstract: A cutting blade is provided for a reaper which can easily position members to be welded, can reduce a welding distortion, can fully ensure the strength of a shank member and can easily be manufactured. The cutting blade comprises a bar-shaped shank member having axially extending grooves formed on an outer peripheral face of a tip portion and having a base end to be fixed to the reaper, and a plate-shaped blade member having a notch portion formed on a base end, wherein the tip portion of the shank member is fitted in the notch portion of the plate-shaped blade member in such a manner that edge portions of the notch portion are fitted in the grooves, and the fitted tip portion of the shank member is welded to a portion of the plate-shaped blade member which is located around the tip portion.

Abstract: It is an object to provide a power driven portable reaper comprising a guard structure for guarding the portable reaper when the portable reaper is to be temporarily put on the ground or during a reaping work. A power driven portable reaper (A) comprises an engine (20) on a base end thereof, a rod member (22) which is elongated forward from a tip side of the engine(20), an impact force generating unit (24) for converting rotation into reciprocation, and a cutting blade (26) provided in a tipmost portion thereof, a plurality of pipes (1A, 1B, 1C) are provided around the engine (20) so as to surround an outer circumference of the engine (20) in a direction from a tip of the engine (20) to a base end of the engine (20). A guard member is provided to be protruding outward from the reaper in the vicinity of the input force generating unit.

Abstract: A cutting blade cover for a brush cutter comprises a central portion 50, a first blade accommodating portion 28, a second blade accommodating portion 29, and a third blade accommodating portion 30. The first, second, and third blade accommodating portions 28, 29, 30 are provided radially from the central portion 50. The first blade accommodating portion 28 includes a first concave portion 31. The second blade accommodating portion 29 includes a second concave portion 36. The third blade accommodating portion 30 includes a third concave portion 40. The first concave portion 31 has an inner shape conforming to an outer shape of the first blade 17 to cover an outer periphery of the first blade 17. The second concave portion 36 has an inner shape conforming to an outer shape of the second blade 18 to cover an outer periphery of the second blade 18. The third concave portion 40 has an inner shape conforming to an outer shape of the third blade 19 to cover an outer periphery of the third blade 19.

Abstract: A joint mechanism for a mowing machine which can be easily assembled and disassembled, including a support member of a casing which houses a cylindrical damper, which prevents vibration of a power unit from being transmitted to a rod, a holder in which the rod is inserted, and a clamp, which clamp prevents the damper and the holder from unintentionally separating from the support member, being inserted therein. The clamp has a flexible arm which extends in the direction of an output shaft of a power unit, and an engagement hook is formed on the tip of the arm. An engagement hole which the engagement hook of the clamp engages is provided on the support member.

Abstract: A muffler for small general-purpose engine includes a case comprising a pair of case halves coupled together and divided into a first chamber and a second chamber by a partition plate. An inlet of the exhaust gas is provided closer to a first end portion of the case in a first case half. An outlet of the exhaust gas is provided closer to a second end portion of the case in a second case half. A recess projecting from the first chamber toward the second chamber guiding the exhaust gas from the inlet toward the second end portion is provided in the partition plate opposite the inlet. A communication orifice is formed in the partition plate at a location offset from the recess and closer to the first end portion than the inlet.