US 9,810,560 B2
Thermal flow meter with temperature detection element positioned on protrusion of circuit package
Noboru Tokuyasu, Hitachinaka (JP); Keiji Hanzawa, Hitachinaka (JP); Takeshi Morino, Hitachinaka (JP); Ryosuke Doi, Hitachinaka (JP); Akira Uenodan, Hitachinaka (JP); and Shinobu Tashiro, Hitachinaka (JP)
Assigned to Hitachi Automotive Systems, Ltd., Hitachinaka-shi (JP)
Appl. No. 14/407,663
Filed by Hitachi Automotive Systems, Ltd., Hitachinaka-shi, Ibaraki (JP)
PCT Filed May 15, 2013, PCT No. PCT/JP2013/063479
§ 371(c)(1), (2) Date Dec. 12, 2014,
PCT Pub. No. WO2013/187170, PCT Pub. Date Dec. 19, 2013.
Claims priority of application No. 2012-135307 (JP), filed on Jun. 15, 2012.
Prior Publication US 2015/0192441 A1, Jul. 9, 2015
This patent is subject to a terminal disclaimer.
Int. Cl. G01F 1/69 (2006.01); G01F 1/696 (2006.01); G01F 1/684 (2006.01); G01F 15/14 (2006.01); G01F 5/00 (2006.01)
CPC G01F 1/69 (2013.01) [G01F 1/6842 (2013.01); G01F 1/6845 (2013.01); G01F 1/6965 (2013.01); G01F 5/00 (2013.01); G01F 15/14 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A thermal flow meter comprising:
a bypass passage for receiving and flowing a part of a measurement target gas flowing through a main passage,
a circuit package that measures a flow rate by performing heat transfer with the measurement target gas flowing through the bypass passage and measuring temperature of the measurement target gas with at least one temperature detecting resistor,
a housing that holds the circuit package,
a temperature detection element for detecting a temperature of the measurement target gas flowing through the main passage, and
covers that cover the housing,
wherein the circuit package has a protrusion provided with the temperature detection element for detecting the temperature of the measurement target gas,
the covers that cover the housing are arranged on opposite sides of the protrusion forming an inlet port at a leading end of the protrusion for receiving the measurement target gas, and
at least one of the covers is provided with an opening for discharging, to the main passage, the measurement target gas that is received from the inlet port and flows along the protrusion.