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.

Abstract: A gear 11 on a crankshaft 10 is made to engage with an internal gear 21 having twice the number of teeth of the gear 11, cams 22 are formed on the exterior surface of the internal gear 21, and the cams 22 are connected with valve actuating mechanisms 40 for actuating an exhaust valve 44 and an intake valve 40 to open or close. The gear 11, the internal gear 21, etc. have the function of an oil pump.

Abstract: There is disclosed a four-cycle engine in which a crankshaft and a cam shaft are disposed generally parallel to each other, and an intake port and an exhaust port are formed in a cylinder head. The intake port and the exhaust port are arranged in such a manner that a line passing through the centers of the intake port and the exhaust port is non-parallel to the axis of the crankshaft. With this arrangement, an intake passage and an exhaust passage can be greatly shortened, and therefore intake efficiency as well as exhaust efficiency can be enhanced, thereby enhancing the performance of the engine. In an air-cooled engine, the overheating of the engine is greatly restrained.

Abstract: A lubrication device for a vertical crank shaft engine. A portion of a crank case, which houses the crankshaft with a small clearance at a given range of the lower side of the crankshaft extending vertically and expands upwards of the housing portion, forms an oil reservoir between the crankshaft, and a pumping member fixed to the crankshaft for rotation is provided in the lower portion of the oil reservoir.

Abstract: An engine having a vertically disposed crankshaft includes an engine cover for closing a whole upper area of an engine body and having a skirt portion protruding downwardly from a periphery of the engine cover, and a cooling fan with a flywheel fixed to an output shaft of the engine below the engine body. The engine further includes a protruded shroud formed integrally on a wall portion of the engine body to completely close an annular clearance between the wall portion and the skirt portion, and a plurality of apertures formed in the protruded shroud to constitute a cooling air intake inlet.

Abstract: A valve gear adapted for a four-cycle engine. Provided are a groove having such a shape folding around a crank shaft with an intersection as to return back to a starting point in two turns, a cam formed on top faces of both banks of aforesaid groove, a tappet arm projecting sideways from a tappet and elastically engaged with aforesaid cam, and a slider supported by aforesaid tappet arm and slidably fitted into aforesaid groove, and aforesaid tappet arm is guided by aforesaid slider to be given a lift by aforesaid cam provided on the outer circumference of the crank shaft.