Humidity measuring device

Patent metadata

Field	Value
Publication number	US-10401314-B2
Application number	US-201615539799-A
Country	US
Kind code	B2
Filing date	Jan 4, 2016
Priority date	Jan 8, 2015
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

The present invention obtains a humidity measuring device capable of performing self-diagnosis with high reliability. This humidity measuring device 20 has a diagnosis processing unit 25 for performing self-diagnosis by using gas temperatures and gas humidities before and after a gas in an ambient atmosphere to be measured is heat-controlled. The diagnosis processing unit has a diagnosis start determining unit 26 for determining whether the self-diagnosis can be started on the basis of an exchange state in the ambient atmosphere to be measured and the gas temperature and the gas humidity before the gas in the ambient atmosphere to be measured is heat-controlled, and a diagnosis continuation determining unit 28 for determining whether the self-diagnosis can be continued on the basis of the gas temperature and the gas humidity that are heat-controlled during the self-diagnosis.

First claim

The invention claimed is:

1. A humidity measurement device comprising:
a temperature measurement element;
a humidity measurement element;
a diagnostic processor that performs a self-diagnosis by using a gas temperature and a gas humidity measured by the temperature measurement element and the humidity measurement element, respectively, before heating control of a gas in a measurement environment, and a gas temperature and a gas humidity of the gas that have been heating-controlled, wherein
the diagnostic processor comprises
a diagnosis-start determination part for determining whether the self-diagnosis can be started or not, based on an exchange state of the measurement environment, and the gas temperature and the gas humidity of the gas before heating control of the gas, and
a diagnosis-continuation determination part for determining whether the self-diagnosis can be continued or not, during the self-diagnosis, based on the gas temperature and the gas humidity of the gas that have been heating-controlled, and
a diagnosis part, wherein, when the diagnosis-continuation determination part determines that the self-diagnosis can be continued, the diagnosis part calculates a specific humidity by using the gas temperature and the gas humidity of the gas before the heating control, calculates an estimate value of relative humidity by using the gas temperature that has been heating-controlled and the specific humidity, and calculates a variation of characteristics from a difference between the gas humidity measured after the heating control and the estimate value.

2. The humidity measurement device according to claim 1 , wherein the humidity measurement device comprises a diagnosis-result reflection part for correcting the gas humidity that has been heating-controlled by adjusting a gas humidity output value by an amount of the variation of characteristics calculated by the diagnosis part.

3. The humidity measurement device according to claim 1 , wherein
the diagnosis-start determination part determines that the self-diagnosis can be started when the gas temperature and the gas humidity before the heating control are in a predetermined range, and
the diagnosis-continuation determination part determines that the self-diagnosis can be continued when the gas temperature and the gas humidity that have been heating-controlled are in the predetermined range.

4. The humidity measurement device according to claim 1 , wherein
the humidity measurement device comprises a control request processor for performing a control request of the self-diagnosis to the diagnostic processor based on an own local-control request or a remote-control request by another device, and
the diagnostic processor, by receiving a control request from the control request processor, performs determination processing for determining whether diagnosis can be started or not, with the diagnosis-start determination part.

5. The humidity measurement device according to claim 4 , wherein the control request processor, by receiving the local-control request or the remote-control request, shifts an internal condition from a request non-reception state to a request reception standby state, and by receiving the local-control request or the remote-control request again within a predetermined period after the shift to the request reception standby state, shifts the internal condition from the request reception standby state to a request reception state to perform a control request of the self-diagnosis.

6. The humidity measurement device according to claim 5 , wherein the humidity measurement device comprises an output part for outputting, to an external device, a state of the heating control and information about which of the local-control request and the remote-control request has caused the diagnosis processing by the diagnostic processor.

7. The humidity measurement device according to claim 1 , wherein the humidity measurement device comprises a diagnosis-result transmitting part for outputting a diagnosis result to an external device when the diagnosis-start determination part determines that the self-diagnosis cannot be started, or when the diagnosis-continuation determination part determines that the self-diagnosis cannot be continued.

8. The humidity measurement device according to claim 1 , wherein
the humidity measurement device comprises a heater element for heating the gas in the measurement environment, and
when the gas temperature and the gas humidity before the heating control are out of a predetermined range of diagnosable temperature/humidity, the diagnosis-start determination part controls the heater element to adjust the gas temperature and the gas humidity in the predetermined range of diagnosable temperature/humidity, and determines that the self-diagnosis can be started when the adjusted gas temperature and gas humidity are in the predetermined range of diagnosable temperature/humidity.

Assignees

• Hitachi Automotive Systems Ltd

Inventors

• Isoya Yuki
• Hoshika Hiroaki
• Yogo Takayuki
• Miki Takahiro
• Yamamoto Takahiro

Classifications

• Y02T10/40

  Engine management systems · CPC title

• F02D2200/0418

  Air humidity · CPC title

• F02D2200/0414

  Air temperature · CPC title

• F02D2200/0402

  the parameter being determined by using a model of the engine intake or its components · CPC title

• F02D2041/285

  the sensor having a signal processing unit external to the engine control unit · CPC title