Flow rate measuring device

Patent metadata

Field	Value
Publication number	US-2016282161-A1
Application number	US-201615073747-A
Country	US
Kind code	A1
Filing date	Mar 18, 2016
Priority date	Mar 23, 2015
Publication date	Sep 29, 2016
Grant date	—

Abstract

A flow rate measuring device includes a housing having a cross-section perpendicular to a Y-direction and taken at a position of an outlet of the housing. The cross-section includes a widest portion having a maximum width along a Z-direction. The cross-section has a width gradually decreasing from the widest portion toward an upstream side end and has a width gradually decreasing from the widest portion toward a downstream side end. A width of the housing at a middle position of the housing in an upstream area is defined as a width W 1. A width at a middle position in a downstream area is defined as a width W 2. A length of the housing in the upstream area is defined as a length L 1. A length in the downstream area is defined as a length L 2. W 1 >W 2 and W 1 /L 1 >W 2 /L 2.

First claim

What is claimed is:

1 . A flow rate measuring device comprising:
a housing disposed in a duct to protrude into an inside of the duct from an outside of the duct through which an air as a measuring target flows, the housing defining a bypass passage therein to take in a portion of the air flowing in the duct, an outlet of the bypass passage being open at an outer wall of the housing; and a flow rate sensor disposed in the bypass passage, wherein a direction in which the air flows in the duct is defined as an X-direction, a direction in which the housing protrudes is defined as a Y-direction, a direction perpendicular to both the X-direction and the Y-direction is defined as a Z-direction, the housing has a cross-section that is perpendicular to the Y-direction and that is taken at a position of the outlet, the cross-section including a widest portion, between an upstream side end and a downstream side end, having a maximum width along the Z-direction, the cross-section having a width along the Z-direction gradually decreasing from the widest portion toward the upstream side end and having a width along the Z-direction gradually decreasing from the widest portion toward the downstream side end, a width of the housing along the Z-direction at a middle position of the housing between the widest portion and the upstream side end in the X-direction is defined as a width W 1 , a width of the housing along the Z-direction at a middle position of the housing between the widest portion and the downstream side end in the X-direction is defined as a width W 2 , a length of the housing along the X-direction between the widest portion and the upstream side end is defined as a length L 1 , and a length of the housing along the X-direction between the widest portion and the downstream side end is defined as a length L 2 , wherein W 1 >W 2 and W 1 /L 1 >W 2 /L 2 .

2 . The flow rate measuring device according to claim 1 , wherein
L 2 >L 1 .

3 . The flow rate measuring device according to claim 1 , wherein
an upstream end of the outlet is located upstream of the widest portion in the X-direction.

4 . The flow rate measuring device according to claim 1 , wherein
the cross-section is symmetrical about an imaginary line perpendicular to the Z-direction.

5 . A flow rate measuring device comprising:
a housing disposed in a duct to extend in a direction inside the duct through which an air flows, the housing defining a bypass passage therein to take in a portion of the air flowing in the duct, an outlet of the bypass passage being open at an outer wall of the housing, wherein a direction in which the air flows in the duct is defined as an X-direction, the direction in which the housing extends is defined as a Y-direction, a direction perpendicular to both the X-direction and the Y-direction is defined as a Z-direction, the housing has a cross-section that is parallel to both the X-direction and the Z-direction and that is taken at a position of the outlet, the cross-section including a widest portion, between an upstream side end and a downstream side end, having a maximum width along the Z-direction, the cross-section having a width along the Z-direction gradually decreasing from the widest portion toward the upstream side end and having a width along the Z-direction gradually decreasing from the widest portion toward the downstream side end, a width of the housing along the Z-direction at a middle position of the housing in the X-direction between the widest portion and the upstream side end is defined as a width W 1 , a width of the housing along the Z-direction at a middle position of the housing in the X-direction between the widest portion and the downstream side end is defined as a width W 2 , a length of the housing along the X-direction between the widest portion and the upstream side end is defined as a length L 1 , and a length of the housing along the X-direction between the widest portion and the downstream side end is defined as a length L 2 , wherein W 1 >W 2 and W 1 /L 1 >W 2 /L 2 .

Assignees

• Denso Corp

Inventors

• Itou Kengo

Classifications

• G01F1/6842 Primary

  with means for influencing the fluid flow · CPC title

• G01F1/692

  Thin-film arrangements · CPC title