Air flow rate measuring device
AssigneeDenso Corporation
InventorTakashi Ooga
Life of this patent
Estimating the term…
Abstract
The present disclosure provides an air flow rate measuring including a casing and a sensor. The casing includes a main-bypass passage that defines an inlet and an outlet, a sub-bypass passage that branches off from the main-bypass passage at a branching area, and a guiding wall that changes, at a position upstream of the branching area, a flow direction of the passing air taken in from the inlet. The inlet and the guiding wall are arranged in an arranging direction along a flow direction of the intake air in the duct. The guiding wall includes an inlet side surface that faces the inlet and is not perpendicular to the arranging direction.
Claims15
An air flow rate measuring device, comprising
- a casing that is attached to a duct through which an intake air for an internal combustion engine flows, a portion of the intake air passing through the casing as a passing air;
- a sensor that detects a flow rate of the passing air, the air flow rate measuring device measuring a flow rate of the intake air based on a detection result of the sensor;
- and
- an attachment surface that attaches the air flow rate measuring device to the duct, wherein
- the casing includes:
- a main-bypass passage that defines an inlet to take in the intake air and an outlet to discharge the passing air taken in from the inlet;
- a sub-bypass passage that branches off from the main-bypass passage at a branching area downstream of the inlet, the sensor being disposed in the sub-bypass passage;
- and
- a guiding wall that is disposed downstream of the inlet, faces the inlet along a first direction parallel to the attachment surface, and changes, at a position upstream of the branching area, a flow direction of the passing air taken in from the inlet, and
- the main-bypass passage includes:
- a guiding passage defined between the inlet and the guiding wall along the first direction and extending along the guiding wall in a second direction perpendicular to the attachment surface;
- and
- a common passage extending from the guiding passage to the outlet and being away from the attachment surface as extending toward the outlet.
An air flow rate measuring device, comprising
- a casing that is attached to a duct through which an intake air for an internal combustion engine flows, a portion of the intake air passing through the casing as a passing air;
- a sensor that detects a flow rate of the passing air, the air flow rate measuring device measuring a flow rate of the intake air based on a detection result of the sensor;
- and an attachment surface that attaches the air flow rate measuring device to the duct, wherein
- the casing includes:
- a main-bypass passage that defines an inlet to take in the intake air and an outlet to discharge the passing air taken in from the inlet;
- a sub-bypass passage that branches off from the main-bypass passage at a branching area downstream of the inlet, the sensor being disposed in the sub-bypass passage;
- and
- a guiding wall that is disposed downstream of the inlet and changes, at a position upstream of the branching area, a flow direction of the passing air taken in from the inlet,
- the guiding wall is an outer circumferential surface of a first curved portion that changes, in the main-bypass passage, a direction of the intake air taken in from the inlet,
- the main-bypass passage includes a second curved portion that changes, at a position downstream of the first curved portion, a direction of the passing air, and
- a direction of the passing air flowing through an area of the main-bypass passage from the second curved portion to the outlet is gradually separated away from a plane surface along which the attachment surface extends.
Dependencies are inferred from the claim text.