Deterioration detector and thermocouple inspection device

Patent metadata

Field	Value
Publication number	US-10209144-B2
Application number	US-201415108869-A
Country	US
Kind code	B2
Filing date	Nov 21, 2014
Priority date	Jan 6, 2014
Publication date	Feb 19, 2019
Grant date	Feb 19, 2019

Abstract

A protection tube thermocouple (5) includes a thermocouple (52), and a protection tube (51) which accommodates the thermocouple (52). The protection tube (51) includes a conical portion (511) formed on a front end (54) side of the protection tube (51); and a hollow portion (53) which extends in the length direction of the protection tube (51) for connecting between a front end (54) and a rear end (55) of the protection tube (51) in the inside of the protection tube (51), and into which the thermocouple (52) is received. The hollow portion (53) in the conical portion (511) has a tapered portion (532) configured such that the sectional area of the hollow portion (53) decreases toward the front end (54).

First claim

The invention claimed is:

1. A deterioration detection device provided with a protection tube thermocouple for detecting deterioration of the protection tube thermocouple by applying current to the protection tube thermocouple, wherein
the protection tube thermocouple includes a thermocouple, and a protection tube which accommodates the thermocouple,
the protection tube includes:
a conical portion formed on a front end side of the protection tube;
a hollow portion which extends in a length direction of the protection tube for connecting between a front end and a rear end of the protection tube in the inside of the protection tube, and into which the thermocouple is received; and
a main body portion formed on the rear end side with respect to the conical portion,

the hollow portion in the conical portion has a tapered portion configured such that a sectional area of the hollow portion decreases toward the front end, and
the hollow portion includes:
a cylindrical portion which is formed on the rear end side with respect to the tapered portion, a radius of the cylindrical portion being set to be larger than a radius of the tapered portion on the rear end side; and
a step portion which is formed within the conical portion on the front end side with respect to a connection position between the conical portion and the main body portion, and which connects between the cylindrical portion and the tapered portion.

2. The deterioration detection device according to claim 1 , wherein
a plating layer is formed on a surface of the protection tube.

3. The deterioration detection device according to claim 1 , wherein
the step portion reduces a wall thickness of the protection tube from the tapered portion towards the cylindrical portion in the conical portion.

4. A deterioration detection device provided with a protection tube thermocouple for detecting deterioration of the protection tube thermocouple by applying current to the protection tube thermocouple, wherein
the protection tube thermocouple includes a thermocouple, and a protection tube which accommodates the thermocouple,
the protection tube includes:
a conical portion formed on a front end side of the protection tube; and
a hollow portion which extends in a length direction of the protection tube for connecting between a front end and a rear end of the protection tube in the inside of the protection tube, and into which the thermocouple is received,

the hollow portion in the conical portion has a tapered portion configured such that a sectional area of the hollow portion decreases toward the front end,
the protection tube thermocouple is mounted on a door portion of a mixing machine, the door portion being opened when a mixing object is taken out from a mixing chamber,
the protection tube includes a contact portion, the contact portion being a portion with which the mixing object comes into contact, and
the deterioration detection device further comprises:
a current supply control unit which supplies current to the thermocouple during a predetermined first time period after the door portion is opened;
a temperature calculating unit which calculates a temperature of the thermocouple after the door portion is opened, with use of a thermoelectromotive force generated in the thermocouple by current supply for the first time period;
an approximation calculating unit which calculates an approximation representing time-wise lowering of ambient temperature of the thermocouple after the door portion is opened, with use of the temperature calculated by the temperature calculating unit;
a subtraction unit which calculates a subtraction value obtained by subtracting a temperature represented by the approximation, from the temperature calculated by the temperature calculating unit;
a wear determination unit which determines whether the contact portion is worn away on the basis of the subtraction value; and
an alert unit which notifies a result of determination by the wear determination unit.

5. The deterioration detection device according to claim 4 , further comprising:
a time period elapse judging unit which judges whether a predetermined second time period has elapsed after the first time period has elapsed, wherein
the approximation calculating unit calculates the approximation, with use of a temperature calculated by the temperature calculating unit during a predetermined sampling time period after the second time period has elapsed.

6. The deterioration detection device according to claim 4 , wherein
the contact portion includes a plating layer.

7. A thermocouple test device for detecting deterioration of a protection tube thermocouple provided with a protection tube including a contact portion, the contact portion being a portion with which a mixing object comes into contact, and a thermocouple accommodated in the protection tube, comprising:
a current supply control unit which supplies current to the thermocouple during a predetermined first time period;
a time period elapse judging unit which judges whether a predetermined second time period has elapsed after the first time period has elapsed;
an approximation calculating unit which calculates an approximation representing time-wise lowering of ambient temperature of the thermocouple, with use of a temperature measured during a sampling time period after the time period elapse judging unit judges that the second time period has elapsed, out of temperatures measured with use of the protection tube thermocouple;
a subtraction unit which calculates a subtraction value obtained by subtracting a temperature represented by the approximation calculated by the approximation calculating unit, from a temperature measured with use of the protection tube thermocouple during the second time period;
a wear determination unit which determines whether the contact portion is worn away on the basis of the subtraction value; and
an alert unit which notifies a result of determination by the wear determination unit.

Assignees

• Kobe Steel Ltd

Inventors

• Fukui Toshihide
• Takahashi Eiji
• Manabe Chitaka

Classifications

• G01K1/08

  Protective devices, e.g. casings · CPC title

• B29B7/724

  for continuous roller mixers, e.g. calenders (B29B7/722 takes precedence) · CPC title

• B29B7/56

  with co-operating rollers {, e.g. with repeated action, i.e. the material leaving a set of rollers being reconducted to the same set or being conducted to a next set} · CPC title

• G01K15/007 Primary

  Testing · CPC title

• B29B7/726

  Measuring properties of mixture, e.g. temperature or density (B29B7/724 takes precedence) · CPC title