A filter element includes first filter media, second filter media, a frame, and a seal member. The frame is coupled to the first filter media and the second filter media, the frame securing the first filter media and the second filter media into a V-shape. The seal member is attached to and extends from the frame. The seal member includes a U-shaped channel structured to receive a ridge of a housing when the filter element is installed in the housing. The seal member is structured to form a seal between the filter element and the housing when the filter element is installed in the housing.

An air filter housing has an inner housing space adapted to receive an air filter element. The air filter housing includes a first housing end and a second housing end located axially opposite the first housing end in relation to the inner housing space, and an outlet pipe extending from the second housing end axially into the inner housing space. The outlet pipe has a center axis and an opening configured to receive clean air from the inner housing space, wherein at least an axial portion of the outlet pipe has a cross-sectional area along a geometrical plane perpendicular to the centre axis which is tapering.

An embodiment variable valve device of a vehicle intake system includes a variable valve housing fixed to a housing of an air cleaner and including a valve passage penetrating the air cleaner, a variable valve flap rotatably coupled to the variable valve housing and configured to perform opening and closing operations based on an intake negative pressure of an engine to open and close the valve passage, and a cam protrusion and a leaf spring provided on the variable valve flap and the variable valve housing, respectively, wherein the cam protrusion and the leaf spring are in contact with each other.

Intake efficiency in an intake system is improved. An intake system takes air through an air inlet duct extending from an air cleaner case, and includes a vortex generator that causes the flow of the intake air inside the air inlet duct to rotate around an axis of the air inlet duct.

There is provided an air cleaner configured to be disposed inside a vehicle body frame, the air cleaner including: an air cleaner case in which an intake chamber is formed; an intake air temperature sensor configured to detect an intake air temperature in the intake chamber; an inlet tube configured to take in air to the intake chamber; and an outlet tube configured to send out air from the intake chamber. The outlet tube has an upstream portion protruding into the intake chamber, and the upstream portion of the outlet tube has a peripheral wall formed with a through hole.

There is provided an air cleaner configured to be disposed inside a vehicle body frame, the air cleaner including: an air cleaner case in which an intake chamber is formed; an air filter disposed in the intake chamber; an inlet tube configured to take in air to the intake chamber; and an outlet tube configured to send out the air from the intake chamber. The inlet tube extends in a front-rear direction. The inlet tube has a bottom wall curved downward in a side view to form a concave curved portion below a discharge port of the inlet tube. The concave curved portion is formed with a drain hole.

A system able to change a cross-sectional area of an air intake tube is provided. The system is disposed between a throttle valve and an air intake tube of an air cleaner, and includes an adjustment device, a control module, and a stepping motor. The adjustment device includes a retaining seat, a rotating disc fitted in the retaining seat, a plurality of blades disposed on the retaining seat and the rotating disc. After the control module receives signals of an engine and the throttle valve and transmits a control signal to the stepping motor, the stepping motor drives the rotating disc to pivot the blades for controlling the cross-sectional area of an opening of the air intake tube.

A system able to change a cross-sectional area of an air intake tube is provided. The system is disposed between a throttle valve and an air intake tube of an air cleaner, and includes an adjustment device, a control module, and a stepping motor. The adjustment device includes a retaining seat, a rotating disc fitted in the retaining seat, a plurality of blades disposed on the retaining seat and the rotating disc. After the control module receives signals of an engine and the throttle valve and transmits a control signal to the stepping motor, the stepping motor drives the rotating disc to pivot the blades for controlling the cross-sectional area of an opening of the air intake tube.

Embodiments of the present disclosure may suppress conduction between an anode and a cathode caused by condensed water in an oil removal apparatus in which oil particles are collected in a filter disposed between the anode and the cathode. An insulating layer may be sandwiched either between the filter and at least one of the anode and the cathode of the bipolar electrode, or within the filter so as to extend in a flow direction of blow-by gas, and may have an insulating property so as to prevent condensed water generated when moisture in the blow-by gas condenses, from connecting the anode and the cathode of the bipolar electrode.

Present embodiments relate to an air filter adapter for use with open style engine air filters. More particularly, but without limitation, present embodiments relate to a filter adapter having a hydrocarbon trap positioned within the adapter.