A variable noise attenuation element is disclosed that comprises a tube, at least one valve seat, at least one valve body and a wire connected to the valve body. The tube has an overall length that defines a first effective length for noise attenuation. The valve seat is disposed in the tube. Retraction of the wire brings the valve body into engagement with the valve seat to selectively define a second effective length of the tube that is less than the overall length.

An electronic throttle valve apparatus including a suction pressure sensor provided on the upstream of a throttle valve to measure pressure of an intake air that flows into the throttle valve is provided. The electronic throttle valve apparatus includes a throttle housing having one side installed in an intake manifold of an engine. Within an inside of the throttle housing, a throttle valve is rotatably provided. The electronic throttle valve apparatus further includes an air tube fastened to the other side of the throttle housing and fastened to an intake flow line, and a suction pressure sensor provided in the air tube and configured to measure pressure of an intake air that flows through the intake flow line. Accordingly, the suction pressure sensor is provided in the air tube that is fastened to the throttle housing, and thus the pressure of the intake air that flows into the throttle valve is easily measured.

A grip, a magnet 140, and a substrate 150 are included. The grip is rotatable between positions where a throttle is fully closed and a position where the throttle is fully open with a rotating shaft as a center. The magnet 140 rotates integrally with the grip. The substrate 150 includes a plurality of Hall elements 165 and 175, and is fixed to face the magnet 140. The plurality of Hall elements 165 and 175 are disposed in such a way that magnetic flux densities different from each other are respectively applied to the plurality of Hall elements 165 and 175 when an external magnetic field acts in a state where the grip is located in the position where the throttle is fully closed.

A throttle valve abnormality determination device includes a permission/rejection determination unit configured to determine whether or not to permit a sticking determination of a throttle valve. The determination unit is configured to prohibit the sticking determination if a first temperature, which is a temperature in a passage through which intake air flows, is less than or equal to a freezing temperature at which the throttle valve may be frozen when an engine is started and, after prohibiting the sticking determination, permit the sticking determination if an integrated value of a heat amount conversion value based on a second temperature, which is a temperature in the passage, and an intake air amount exceeds a threshold value when the second temperature is greater than or equal to a de-freezing temperature at which a frozen portion of the throttle valve is de-frozen.

An angle detection mechanism to detect a rotation angle of a rotation body includes a first detection unit to cause a first output value to constantly change in response to an angle change of the rotation body in the entire region of a specific rotation range and to set a change quantity of the first output value relative to the angle change in a first rotation region of the specific rotation range to be greater than a change quantity in a non-first rotation region, and a second detection unit to cause a second output value to constantly change in response to an angle change and to set a change quantity of the second output value in a second rotation region including a rotation region different from the first rotation region to be greater than a change quantity in a non-second rotation region.

Disclosed is a verification system including a throttle actuation verification system. The verification system may include one or more sensors positioned at a location that will receive a force applied by an operator when a throttle lever is engaged or loaded for the intention to be actuated by the operator. A signal from the sensor is compared to a throttle position.

An electronic throttle valve apparatus including a suction pressure sensor provided on the upstream of a throttle valve to measure pressure of an intake air that flows into the throttle valve is provided. The electronic throttle valve apparatus includes a throttle housing having one side installed in an intake manifold of an engine. Within an inside of the throttle housing, a throttle valve is rotatably provided. The electronic throttle valve apparatus further includes an air tube fastened to the other side of the throttle housing and fastened to an intake flow line, and a suction pressure sensor provided in the air tube and configured to measure pressure of an intake air that flows through the intake flow line. Accordingly, the suction pressure sensor is provided in the air tube that is fastened to the throttle housing, and thus the pressure of the intake air that flows into the throttle valve is easily measured.

A flow measuring device includes a housing including a bypass passage and a flow sensing chip located in the bypass passage and including a sensing surface portion. A throttle portion that is a part of a flowing passage wall facing a sensing surface portion throttles a cross-sectional area of a bypass passage. A position where the throttle portion starts is referred to as a start point position, and a position of the throttle portion where a distance between a gravity center of the sensing surface portion and the throttle portion is shortest is referred to as an end point position. The start point position and the end point position define an imagination line, and the imagination line and the flowing direction define an angle that is in a range from 0 degrees to 20 degrees.

A flow measuring device includes a housing including a bypass passage and a flow sensing chip located in the bypass passage and including a sensing surface portion. A throttle portion that is a part of a flowing passage wall facing a sensing surface portion throttles a cross-sectional area of a bypass passage. A position where the throttle portion starts is referred to as a start point position, and a position of the throttle portion where a distance between a gravity center of the sensing surface portion and the throttle portion is shortest is referred to as an end point position. The start point position and the end point position define an imagination line, and the imagination line and the flowing direction define an angle that is in a range from 0 degrees to 20 degrees.

An engine kill switch and a throttle lever position sensor switch both remote from the engine and connected by a pair of wires to a microcontroller for controlling a spark initiated combustion of an air-fuel mixture in a cylinder of the engine. The switches may be received in the same housing and mounted in an operator handle housing of a hand held power tool.