Abstract: A filter element comprises an oil-impregnated filtering member, and a transmission preventing layer formed on a downstream side of the filtering member, for restricting transmission of at least the carbon dusts from the oil-impregnated filtering member. The filtering member may be formed like a ridge-like-folded structure. The transmission preventing layer may be formed of a coating layer having a resistance against a viscous oil that is impregnated in the filtering member. This coating layer may be formed uniformly as a whole or the thickness or the content of the coating layer may be increased partially. A ventilation shutting-off member (filling layer) may be formed as the transmission preventing layer in the root portion areas of the ridge portions. The transmission preventing layer may comprise a resistant component that is insoluble in the oil that is impregnated in the filtering member.

Abstract: A filter element comprises an oil-impregnated filtering member, and a transmission preventing layer formed on a downstream side of the filtering member, for restricting transmission of at least the carbon dusts from the oil-impregnated filtering member. The filtering member may be formed like a ridge-like-folded structure. The transmission preventing layer may be formed of a coating layer having a resistance against a viscous oil that is impregnated in the filtering member. This coating layer may be formed uniformly as a whole or the thickness or the content of the coating layer may be increased partially. A ventilation shutting-off member (filling layer) may be formed as the transmission preventing layer in the root portion areas of the ridge portions. The transmission preventing layer may comprise a resistant component that is insoluble in the oil that is impregnated in the filtering member.

Abstract: In a variable intake apparatus for a multi-cylinder internal combustion engine, each cylinder is allowed to communicate with each other through air intake passageways including at least a pair of air intake passageway portions. Further, an air intake control valve integrally provided with a pair of valve bodies is disposed at an opening which is formed at a partition wall. The partition wall is formed between the intake air collecting chamber and the air intake passageway. Further more, the air intake control valve is actuated according to engine speeds of the internal combustion engine such that the air intake passageway portion is opened and closed by one of the valve bodies whereas the opening in the partition wall is opened and closed by the other of the valve bodies.

Abstract: In a variable intake apparatus for a multi-cylinder internal combustion engine, each cylinder are allowed to communicate with each other through air intake passageways including at least a pair of air intake passageway portions. Further, an air intake control valve integrally provided with a pair of valve bodies is disposed at an opening which is formed at a partition wall. The partition wall is formed-between the intake air collecting chamber and the air intake passageway. Further more, the air intake control valve is actuated according to engine speeds of the internal combustion engine such that the air intake passageway portion is opened and closed by the valve body whereas the opening in the partition wall is opened and closed by the other valve body.

Abstract: A variable intake apparatus for an in-line four-cylinder internal combustion engine includes a rotary valve 3 provided between an intermediate portion along the length of four air intake passages 41 to 44 and an intake air collecting chamber 5, and a control means switching the rotary valve 3 in triple stages in response to the engine speed. The control means is constructed such that at a low speed range, communications are blocked off between the adjacent intake passageways 41 and 42, 42 and 43, 43 and 44, at an intermediate speed range, communications are established between pairs of intake passageways 41 and 44, 42 and 43, and at a high speed range, communications are established not only between the adjacent intake passages 41 and 42, 42 and 43, 43 and 44, but also between the respective air intake passageways 41 to 44 and the intake collecting chamber 5.

Abstract: A variable intake apparatus for an in-line four-cylinder internal combustion engine includes a rotary valve 3 provided between an intermediate portion along the length of four air intake passages 41 to 44 and an intake air collecting chamber 5, and a control means switching the rotary valve 3 in triple stages in response to the engine speed. The control means is constructed such that at a low speed range, communications are blocked off between the adjacent intake passageways 41 and 42, 42 and 43, 43 and 44, at an intermediate speed range, communications are established between pairs of intake passageways 41 and 44, 42 and 43, and at a high speed range, communications are established not only between the adjacent intake passages 41 and 42, 42 and 43, 43 and 44, but also between the respective air intake passageways 41 to 44 and the intake collecting chamber 5.