Abstract: An oil separating chamber for separating oil contained in blow-by gas is arranged outside a transmission member passage connecting a crank shaft with a cam shaft of a valve system and at an abutting surface between a cylinder block and a cylinder head. Partition walls perpendicular to the abutting surface for dividing the oil separating chamber into a plurality of small subchambers are alternatively arranged at the cylinder block and the cylinder head to form a labyrinth structure. The small subchamber at one end of the plurality of small subchambers is provided with a blow-by gas intake passage communicated with the transmission member passage. The small subchamber at the other end is provided with a blow-by gas exhaust passage for returning blow-by gas to an air cleaner. Each of the small subchambers not provided with the blow-by gas intake passage is provided with an oil return passage communicating with the transmission member passage.

Abstract: To provide an apparatus for feeding secondary air to exhaust gas in an engine. The apparatus includes a cylinder head having an exhaust port for discharging exhaust gas from a combustion chamber and a secondary air feed passage for feeding secondary air to exhaust gas flowing through the exhaust port. The apparatus is capable of making a length of the secondary air feed passage as short as possible while preventing the permeation of exhaust gas into the secondary air feed passage. This avoids the enlargement of the entire engine, when disposing a reed valve in the engine, since the reed valve is mounted to the cylinder block. A secondary air passage includes a first passage portion extending in a straight line with one end opened toward the inner surface of an exhaust port, toward the downstream side of exhaust gas in the flowing direction.

Abstract: To make it possible to extract air from a water pump without the need for a dedicated structure for air extraction in the water pump which supplies cooling water to a cooling jacket on a cylinder head or cylinder block of a horizontally opposed or V-type engine. A circular pump chamber for rotatably housing an impeller inside a pump housing of a water pump includes an upper discharge path extending diagonally upwards and connecting to an upper end section of the pump chamber, and a lower discharge path extending diagonally downwards and connecting to a lower end section of the pump chamber. First and second connecting pipes respectively extending in a straight line along a line extended from the upper and lower discharge paths have inner ends communicating with the upper and lower discharge paths, and outer ends forming first and second discharge ports.

Abstract: To provide a four-cycle engine for a vehicle, in which a cylinder bore is disposed in such a manner that the axial line thereof extends substantially in the horizontal direction. Furthermore, a cam shaft is disposed between an intake valve and an exhaust valve which have operational axial lines crossing each other in an approximately V-shape. The engine is capable of making the position of the outer end portion of an exhaust valve as close to the axial line of a cylinder bore as possible, thereby making the mounting position of the engine as low as possible. A cam shaft is disposed above the axial line of a cylinder bore and on a projection plane perpendicular to the axial line of a crank shaft, including the axial line of the cylinder bore. Furthermore, an angle formed between the axial line of the cylinder bore and the operational axial line of an intake valve is set to be larger than an angle formed between the axial line of the cylinder bore and the operational axial line of an exhaust valve.

Abstract: A seat for receiving a fuel injecting valve, is provided in an intake pipe at a portion closer to an intake port, than a straight line connecting a crossing point P, of a first and a second center lines CL, and CL, to a curved center C. of the bent pipe portion; fastening seats and for fastening the mounting member, to the intake pipe, is provided on the intake pipe, at such a position as to put the straight line between the seat and the fastening seats and; and the seat and the fastening seats and are formed in parallel to each other.

Abstract: To provide a breather apparatus for a horizontally-opposed type or a V-type engine in which first and second cylinder blocks having first and second cylinder bores are commonly connected to a crank case in such a manner that the axial line of the first cylinder bore is offset from the axial line of the second cylinder bore to one side of the crank shaft along the axial line of the crank shaft. A cam chain chamber is provided in the crank case, the cylinder blocks and the cylinder heads on one side of the crank shaft along the axial line of the crank shaft. Furthermore, a breather chamber is formed in the second cylinder block, the second cylinder head, and the crank case at a position between the cam chain chamber and the second cylinder bore. The breather chamber has a relatively large capacity, while enlargement of the engine is avoided.

Abstract: A powdered leather which is composed of at least 85% by weight of cortex, at most 2% by weight of oil and fat, and at most 0.5% by weight of Na.sup.+ and Ca.sup.2+ ions capable of being eluted by water and which has an average particle size (D.sub.50) of at most 7 .mu.m, a standard deviation of the average particle size being at most 3 .mu.m. With this powdered leather, it is possible to thin films, coatings, fibers, etc. which would hardly be deteriorated with time.

Abstract: A rubber composition containing a powdered leather of a dispersion mixture comprising from 10 to 400 parts by weight of a powdered leather with a skin component of greater than 75% by weight, a total amount of Na.sup.+ ions and Ca.sup.2+ ions extractable with water of less than 0.5% by weight and an average grain size D.sub.50 of from 10 .mu.m to 250 .mu.m, and 100 parts by weight of rubber obtained from a raw material for the powdered leather by performing coarse pulverization, water washing, dewatering, steams swelling, drying and powderization and then separation into particles of a desired average grain size depending on the purpose of use, as well as a molding product obtained from the rubber composition.