Hot-Type Fluid Measurement Device

Patent metadata

Field	Value
Publication number	US-2016011031-A1
Application number	US-201414773100-A
Country	US
Kind code	A1
Filing date	Jan 10, 2014
Priority date	Mar 5, 2013
Publication date	Jan 14, 2016
Grant date	—

Abstract

In order to achieve measurement with high precision by suitably correcting a measurement error, a hot-type fluid measurement device includes a module having a passage section and a circuit chamber, a sensor element disposed in the passage section, and a circuit element disposed in the circuit chamber. The circuit element includes a correction section that corrects flow rate information detected by the sensor element from temperature difference information of a temperature of a fluid and a temperature of the module, and at least one temperature of the temperature of the fluid or the temperature of the module.

First claim

1 . A hot-type fluid measurement device comprising:
a module that includes a passage section and a circuit chamber; a sensor element that is disposed in the passage section; and a circuit element that is disposed in the circuit chamber, wherein the circuit element includes a correction section that corrects flow rate information detected by the sensor element from temperature difference information of a temperature of a fluid and a temperature of the module, and at least one temperature of the temperature of the fluid and the temperature of the module.

2 . The hot-type fluid measurement device according to claim 1 ,
wherein the sensor element has a diaphragm constructed in a semiconductor substrate, a heating resistor provided on the diaphragm, and a plurality of temperature detectors provided on an upstream side and a downstream side of the heating resistor on the diaphragm, wherein the sensor element has a first temperature sensor measuring the temperature of the fluid and a second temperature sensor measuring the temperature of the module, and wherein the second temperature sensor is provided on an inside of the circuit chamber.

3 . The hot-type fluid measurement device according to claim 2 ,
wherein the first temperature sensor is provided in a position that is outside of the module and exposed to the fluid.

4 . The hot-type fluid measurement device according to claim 3 ,
wherein the first temperature sensor is supported by a support member protruded from the module and the support member includes a heat transfer suppressing section that suppresses heat transfer from the module to the first temperature sensor.

5 . The hot-type fluid measurement device according to claim 2 ,
wherein the first temperature sensor is provided on the semiconductor substrate.

6 . The hot-type fluid measurement device according to claim 2 ,
wherein the semiconductor substrate has a bridge circuit formed of a first thermosensitive resistor of which a resistance value changes according to a temperature of the heating resistor, a second thermosensitive resistor of which a resistance value changes according to the temperature of the fluid, a third thermosensitive resistor of which a resistance value changes according to the temperature of the fluid, and a fourth thermosensitive resistor of which a resistance value changes according to the temperature of the fluid, wherein the circuit element has a control section that controls a heating amount of the heating resistor using an output of the bridge circuit, and wherein the first temperature sensor is configured of at least one or more of the second thermosensitive resistor, the third thermosensitive resistor, and the fourth thermosensitive resistor.

7 . The hot-type fluid measurement device according to claim 2 ,
wherein the circuit element has a measuring circuit that inputs a signal from the sensor element and outputs a measurement result of a predetermined parameter of fluid, and integrates the measuring circuit and the second temperature sensor on the same semiconductor chip.

8 . The hot-type fluid measurement device according to claim 1 ,
wherein the correction section has at least one memory data of a first correction memory data that stores a first correction amount corresponding to a temperature difference between the temperature of fluid and the temperature of the module, and a second correction memory data that stores a second correction amount corresponding to at least one temperature of the temperature of the fluid or the temperature of the module.

9 . The hot-type fluid measurement device according to claim 1 ,
wherein the correction section includes calculation means for calculating the correction amount from the temperature difference of the fluid and the module, and at least one temperature of the temperature of the fluid and the temperature of the module.

10 . The hot-type fluid measurement device according to claim 1 ,
wherein the sensor element has a diaphragm configured on a semiconductor substrate, a heating resistor provided on the diaphragm, and a plurality of temperature detectors provided on an upstream side and a downstream side of a heating resistor on the diaphragm, wherein the sensor element and the circuit element are integrated on the same semiconductor substrate and the semiconductor substrate has a module temperature sensor that measures the temperature of the module, and the circuit element has a measuring circuit that inputs a signal from the sensor element and outputs a measurement result of a predetermined parameter of the fluid.

11 . The hot-type fluid measurement device according to claim 10 ,
wherein the semiconductor substrate has a plurality of thermocouples, and wherein the plurality of temperature detectors are respectively contact points of one side of the thermocouple.

12 . The hot-type fluid measurement device according to claim 11 ,
wherein the plurality of thermocouples has thermocouples of which the contact points of the other side are provided on an outside of the diaphragm, and wherein the temperature difference between the temperature of the fluid and the temperature of the module is measured by thermocouples of which the contact points of the other side are provided on the outside of the diaphragm.

13 . The hot-type fluid measurement device according to claim 12 ,
wherein the contact points on the other side, of thermocouples of which the contact points on the other side are provided on the outside of the diaphragm and the module temperature sensor are arranged to be close.

14 . A flow rate detection system comprising:
flow rate detecting means for detecting a flow rate of a fluid flowing through an intake pipe; fluid temperature detecting means for detecting a temperature of the fluid flowing through the intake pipe; module temperature measuring means for detecting a temperature of a module of the flow rate detecting means; and correcting means for correcting a measurement result of the flow rate detecting means, wherein the correcting means corrects flow rate information detected by the flow rate detecting means using temperature difference information of the temperature of the module detected by the module temperature measuring means and the temperature of the fluid detected by the fluid temperature detecting means, and fluid temperature information that is measured by the fluid temperature detecting means or estimated by the module temperature measuring means.

15 . A flow rate detection system comprising:
flow rate detecting means for detecting a flow rate of a fluid flowing through an intake pipe; temperature difference detecting means for detecting a temperature difference between a temperature of the fluid and a temperature of a module; module temperature detecting means for detecting the temperature of the module; and correcting means for correcting flow rate information detected by the flow rate detecting means based on temperature difference information detected by the temperature difference detecting means and module temperature information detected by the module temperature detecting means.

16 . The flow rate detection system according to claim 14 , further comprising:
communicating means for transmitting each type of information detected by each detecting means to the correcting means.

Assignees

• Hitachi Automotive Systems Ltd

Inventors

• Asano Satoshi
• Matsumoto Masahiro
• Nakano Hiroshi
• Sato Ryo

Classifications

• G01F5/00

  Measuring a proportion of the volume flow · CPC title

• G01F1/692

  Thin-film arrangements · CPC title

• G01F1/6965

  comprising means to store calibration data for flow signal calculation or correction · CPC title

• G01F1/696 Primary

  Circuits therefor, e.g. constant-current flow meters · CPC title