Batne of Document] DESCRIPTION
[Title of the Invention] SURFACE TEMPERATURE MEASURING APPARATUS AND
SURFACE TEMPERATURE MEASURING METHOD
[Technical Field]
5 [OOOl]
The present invention relates to an apparatus that measures a surface ternperature
of a temperature measurement target material such as a steel material by radiant
temperature measuring, and a method of measuring the satne. The present invention
particularly relates to a surface temperature measuring apparatus that is capable of
10 accurately tneasuri~lga surface temperature of a tetnperature measuremeut target material
such as a steel material (e.g., a wheel, a steel pipe, a steel sheet, or a rail) in a cooling
process with water, and a method of mcasuri~~thge same.
[Background Art]
[0002]
15 In order to improve the quality and productivity of a temperature ~neasurement
target ~nateriasl uch as a wheel, a steel pipe, a steel sheet, or a rail, it has become important
to manage the temperature of the temperature measurement target material in a cooli~lg
process. When the surface temperature of the temperature measurement target material is
measured by use of a radiation tl~er~noinetienr a cooli~lgp rocess in a hot rolling line or a
20 heat treatment-and-cooling line of the tcmpcrature ~neasurc~neta~rg~ett material, for
exa~nple, so~netilnes there may be steam or scattered cooling water between the
temperature measurement target material and the radiation thennometer. Alternatively, a
surface of the temperature measurement target material may be covered with a water film
or be submerged. Under such an environment, thermal radiation light emitted fiom tlle
25 temperature measareme~t~atr get material may be absorbed into water vapor, steam, cooling
water, or the like, or may be scattered, and accordingly, the measured ternperature value
may include an error or the measurement may fail.
[0003]
Accordingly, in order to reduce errors in nleasuring the tenlperature (hereinafter
also referred to as temperature ~neasurcnlcnet rrors), generated by the above factors, and to
5 enable accurate radiant tenlpcrature measuring, there have been proposed various methods
of measuring a surface tcnlperature of a steel ~naterial according to the related art. For
example, Patent Docunlent 1 proposes a method of measuring a surface temperature of a
steel material by forming a water column between a radiation thernlometer and the surface
of the steel material by ejection of purge water from a nozzle toward the surface of the
10 steel material, and by detecting the radiant energy of the ther~nal radiation light emitted
from the steel ntaterial through the water colu~nn.
[0004]
More specifically, ~vith the temperature measuring method disclosed in Patent
Document 1, a water column is formed between a radiation themlometer aild a
15 measurement target. The radiation thermometer is configured to ineasure a surface
temperature of the nleasurcnlent target on the basis of the radiant energy emitted from the
measurement target. Frorn all the radiant energy emitted from the measurement target,
part of the radiant energy is absorbed into the water colutnn. Thus, considering the
absorption, while the radiant energy is corrected, the surface temperature of the
20 ~neasuremerltt arget is measured by use of the radiation ther~~~ometeTr.h is method is
characterized by setting the telnperature of the water c o l u n ~to~ 6 0 OC or higher to forn the
water column.
[OOOS]
With the lnethod disclosed in Patent Docu~nent 1, since the water column is
25 fo~nled between the radiation thermometer and the measurenlent target, water vapor or
scattered water is unlikely to enter a part ~vllere the water colunln is fornled, and it is
possible to reduce the temperature measurenient errors caused by absorption or scattering
of the radiant energy by water vapor or scattered water. Further, with the method
disclosed in Patent Docutnent 1, since the tetnperature of the water colunnl is set to 60 O C
or highel; a boiling film is likely to be formed on the surface of the measurement target in
5 contact with the water column. Accordingly, it becomes possible to suppress a decrease
in the surface telnperature of the measurenlent target and to reduce cooling unevenness of
the n~easuren~entta rget without damaging the representativeness of the measured
tenlperature value, which is advantageous.
[0006]
10 Howevel; the nletllod disclosed in Patent Document 1 has the following problems.
A heater for increasing the tenlperature of the water colunln to 60 OC or higher is necessary.
A high energy cost is also necessary to increase the temperature of the water. Further,
because a thickness measuring apparatus for measuring the thickness of the water colutnn
(using an ultrasonic systetn, for example) is necessary, the dimension of the entire
15 apparatus is large, and accordingly, it becomes difficult to install the apparatus in a narrow
space such as a space between steel tnaterial carrying rolls. Ful-tl~ern~oreev,e n when the
tliiclu~essn leasuring apparatus is installed, the maintainability may be hindered because the
attachnlent and detachncnt nlay be troublesome, and a trouble of the tliickness nleasuring
apparatus may degrade the stability and reliability of the measured temperature value.
20 [0007]
In order to solve at least one of the above problems and the like of the method
disclosed in Patent Document 1, the present inventors have proposed a method disclosed in
Patent Document 2. Specificall]: the nlethod disclosed in Patent Doculllent 2 is a metl~od
of nieasuring a surface tenlperature of a tenlperature measurement target steel nlaterial by
25 detecting tliertnal radiation light emitted from the bottom surface of the teniperature
nleasurenlent target steel material by use of a radiation tl~ern~omettehra t is disposed to be
opposed to the bottonl of the temperature measurement target stccl matcrial tlxough purge
water ejected from a nozzle toward the botto~n surface of the temperature lneasurenlent
target steel material. With this method, on the basis of the position of a path line of the
temperature measure~nent arget steel material, all heads of the purge water are set within a
5 predeternlined range (claim 2 of Patent Document 2). Furthel; this tnethod proposes to
set the wavelength of the thennal radiation light detected by the ~adiationth ennometer to
0.9 11111 or shorter (claim 3 of Patent Document 2).
[OOOS]
According to the above method disclosed in Patent Docu~nen2t , since all heads of
10 the purge water are set within a predeternlined range, collision pressure of the purge water
on the bottom surface of tl~ete mperature measurement target steel lnaterial is suppressed,
and even when the purge water is at roonl temperature, cooling can be suppressed.
Accordingly, according to the method disclosed in Patent Document 2, it becomes possible
to obtain the advantage that the high energy cost for increasing the temperature of the
15 water, which is necessary in Patent Document 1, is unnecessary. Further, by setting the
wavelength of the thermal radiation light detected by the radiation thermometer to 0.9 pm
or shorter, it becomes possible to obtain the advantage that the thickness measuring
apparatus for tneasuring the thickness of the water column is unnecessary.
[0009]
20 However, according to the above method disclosed in Patent Docun~cnt 2, in a
case in which the temperature of the top surface, side surfaces, and the like of the
temperature measure~nent target steel material is measured, the purge water collides with
the temperature tneasure~nent target steel material, and accordingly, temperature
~ueasurement errors may be generated by cooling of tlle ssuface of the temperature
25 nleasurement target steel material. Further, since the \wavelength of the thermal radiation
light detected by the radiation thennometer is set to 0.9 [un or shorter, the lower limit of
the surface tenlperature of the steel nlaterial ~vllichc an be subjected to radiant tenlperatt~re
measuring is approxinlately 500 "C. Considering recent requirement for high quality of
the steel material, it has become important to manage the surface tcrnperature it1 a low
tenlperature region of approximately 200 "C. Accordingly, it is difficult to manage
5 appropriate temperatures with the tilethod by \vliiclich only the surface temperature of
approximately 500 OC or higher can be measured.
[OO lo]
I11 addition, as a technique to measure the surface temperature of a temperature
measurement target material, generally, the temperature is measured by pressing a
10 temperature sensor of a thermocouple wire lightly on the te~ilperature measurement target
material. The tenlperature sensor of tile tliern~ocouple is fixed on a rear surface of a
contact plate at the edge of a temperature measurement unit. However, since the
tenlperature sensor of the thermocouple wire is pressed by the contact plate on the
temperature iiieasurement target material, in a cooling process of water cooling, water
15 cnters a space between the contact plate and the tenlperature measurement target material,
and the temperature sensor of the tlier~ilocouplew ire contacts the water. Accordingly, it
becomes difficult to measure the surface temperature of the tetilperature measurenlent
target material accnrateljr.
[Prior Art Docun~cnt(s)]
20 [Patent Document(s)]
[OOl 11
[Patent Document I] JP H8-295950A
[Patent Document 21 JP 2006-17589A
[Sumnlary of the Invention]
25 [Proble~n(s) to Be Solved by the Invention]
[0012]
The present invention has been made to solve at least one of the problems of the
related art and aims to provide a surface temperature measuring apparatus that is capable of
accurately measuring a surface temperature of a temperature ineasurement target inaterial
suc11 as a steel material (e.g., a whcel, a steel pipe, a steel sheet, or a rail) in a cooling
5 process with water, and a method of measuring the same.
[Means for Solving the Problem(s)]
[0013]
In order to solve at least one of the above proble~ns, according to the presemt
invention, there is provided a surface tenlperature measuring apparatus including a
10 radiation thermometer configured to detect thermal radiation light emitted from a surface
of a temperature ineasurement target material in a cooling process with \vatel; a housing
having an opening on a temperature measurement target material side, the housing storing,
in an inside of the housing, at least a light receiving unit of the radiation thermometer
among structural elements of the radiation therillornetel; and an optical glass that is fit and
15 sealed in the inside of the housing between the temperature measure~nent target material
and the light receiving unit of the radiation thermonletel; the optical glass being configured
to transmit the thermal radiation light. The optical glass has, on the temperature
tneasurement target material side, an end surface that is adjacent to the surface of the
temperature measurement target material.
20 [0014]
In the surface temperature measuring apparatus, the end surface of the optical
glass on the temperature measurement target ~naterial side may be located at a position
where water is present in a space between the end surfacc of the optical glass 011 the
temperature measurement target nlaterial side and the surface of the temperature
25 measurement target material, and the light receiving unit of the radiation thennometer may
receive the thermal radiation light emitted fro111 the surface of the temperature
measurement target material thro~ough water that is present in the space between the surface
of the temperature lmeasurement target material and the end surface of the optical glass on
the temperature tneasure~l~etnatr get material side.
[0015]
5 The radiation thernlometer may detect light having any one of wavelength bands
of 0.7 to 0.9 pm, 1.0 to 1.2 Inn, and 1.6 to 1.8 I I I I I .
[0016]
The surface temperature measuring apparatus may include a keeping member
configured to keep a gap between the surface of the temperature measurement target
10 material and the end surface of the optical glass on the temperature measurement target
material side substantially constant.
[00 1 71
The surface of the temperature measuretnent target material on which the
radiation thennometer detects the thermal radiation light may be a plane that is
15 substantially vertical to a horizontal direction, and the surface temperature measuring
apparatus may calculate a nleasured temperature value by correcting an output value of the
radiation thermo~neter by use of a transmittance of the thermal radiation light with respect
to a thickness of \\rater corresponding to a length that is substantially half of the gap
bet~veenth e surface of the temperature measurement target tnaterial and the end surface of
20 the optical glass on the temperature measurement target material side.
[OO 1 81
The surface of the temperature measurelnent target material on which the
radiation ther~nonleterd etects the tl~cr~naral diation light may be a top surface of the
temperature measure~nent target nlaterial that is substantially parallel to a horizontal
25 direction, and the gap between the surrace of the temperature measurement target material
and the end surface of the optical glass on the temperature measurenlent target material
side may be 2.5 nlnl or sl~oiter.
[00 191
The surface of the temperature measurement target nlaterial on which the
radiation thermometer detects the thermal radiation light may be a plane that is
5 substantially vertical to a horizontal direction, the light receiving unit of the radiation
thermometer may receive the thennal radiation light emitted through the water that is
present in the space between the surface of the temperature measurement target material
and the end surface of the optical glass 011 the temperature measurement target material
side, and the gap between the surface of the temperature measurement target material and
10 the end surface of the optical glass on the temperature nieasurenlent target material side
may be 1.0 nlnl or shorter.
[OO2O]
The surface temperature measuring apparatus may include a water supply
apparatus configured to supply water to the space between the surface of the temperature
15 measurement target material and the end surface of the optical glass on the temperature
measurement target material side.
[O021]
In order to solve at least one of the above problems, according to another aspect of
the present invention, there is provided a surface temperature nleasuring apparatus
20 including a radiation thenno~neterc onfigured to detect thennal radiation light emitted from
a surface of a temperature measurement target material in a cooling process with watel; a
housing having an opening on a temperature measurement target material side, the llousing
storing, in an inside of the housing, at least a light receiving unit of the radiation
thern~onleter among structural elenlents of the radiation thernlometel; an optical glass that
25 is fit and sealed in tlle inside of the housing between the temperature measurement target
material and the light receiving unit of the radiation thermometer, the optical glass being
configured to trans~nit the thermal radiation light, and a keeping member configured to
keep a gap between a surface of the temperature measurement target material and an end
surface of the optical glass on the temperature measurement target tnaterial side
substantially constant.
5 [0022]
In order to solve at least one of the above problems, according to another aspect of
the present invention, there is provided a surface temperature measuring method of
measuring a surface temperature of a temperature measurement target material by detecting,
by use of a radiation thermometer, thermal radiation light emitted fiom a surface of the
10 temperature measurement target material in a cooling process with water, the ~netliod
including interposing an optical glass configured to transmit the thermal radiation light
between the temperature measurement target material and a light receiving unit of the
radiation thernlometel; and locating an end surface of the optical glass on a temperature
~neasurement arget material side adjacently to the surface of the temperature tneasurement
15 target material and measuring the surface tetnperatnre of the temperature measure~nent
target material.
[0023]
In a case in which the temperature measurement target material is a steel material
having a disk shape, a colunmar shape, or a cylindrical shape having an outer peripheral
20 surface, when ~neasuring the surface temperature of the temperature measurement target
material, a tenlperature of the outer peripheral surface of the temperature measurement
target material may be ~neasured by use of the radiation thermometer \vliile the gap
between the outer peripheral surface of the temperature measurelnent target material and
the end surface of the optical glass on the temperature measurement target material side is
25 kept substantially constant, in a state in which the temperature measure~nent arget rnaterial
is rotated around a center axis of the tenlperature ~neasure~netnatr get material as a rotation
center and the outer peripheral surface of the temperature n~easuremeat target material is
cooled by water.
[Effect(s) of the Inve~ltion]
[0024]
5 As described above, according to the present invention, it is possible to provide a
surface temperature measuring apparatus that is capable of accurately measuring a surface
tenlperature of a temperature measurement target nlaterial such as a steel material (e.g., a
wl~eela, steel pipe, a steel sheet, or a rail) in a cooling process wit11 water, and a nlethod of
measuring the same.
10 [Brief Description of the Drawing(s)]
100251
[FIG. 11 FIG. 1 is a schematic plan view showing a surface temperature measuring
apparatus according to an cnlbodinlent of the present invention.
[FIG. 21 FIG. 2 is a schematic fiont view showing a surface temperature tneasuring
15 apparatus according to tile embodiment when seen from direction A in FIG. 1.
[FIG. 31 FIG. 3 is a sclien~atics ide view showing a surface temperature measuring
apparatus when seen from direction B in FIG. 1.
[FIG. 41 FIG. 4 is a schenlatic diagram showing a purge rnechanis~in~ a~n inside of
a liousing.
20 [FIG. 51 FIG. 5 is a graph showing a relation between a wavelength of thermal
radiation light and transmittance of thennal radiation light with respect to a thickness of
water.
[FIG. 61 FIG. 6 is a graph showing results of observation of a state of water that is
present between a steel slieet and an end surface of an optical glass by a gap between a top
25 surface (horizontal plane) of the steel slieet that is substantially parallel to a horizontal
direction or a plane (vertical plane) of the steel sheet that is substantially vertical to the
Iiorizot~tald irection and the end surface of the optical glass.
[FIG. 71 FIG. 7 shows an example of a charge state of water that is present
between a surface of a tetnperature ineasuretnetlt target material and an end surface of an
optical glass on a temperature nieasurement target tnaterial side.
5 [FIG. 81 FIG. 8 is a graph showing an example of a relation between a charge rate
of water and a temperature n~easurelnenet rror.
[FIG. 91 FIG. 9 sho~vs a relation between a part where later is charged and a
measurement field of a detection unit of a radiation thermometer.
[FIG. 101 FIG. 10 is a sche~natic diagram sho\ving an experimental apparatus for
10 evaluating accuracy of surface temperature measurement on a vertical plane of a steel sheet
in a cooling process with water.
[FIG. I I ] FIG. 11 is a graph showing tenperature measnretnent results obtained by
an experitnental apparatus shown in FIG. 10.
[Mode(s) for Carrying out the Invention]
15 [0026]
4 . Overview of the present invention>
A surface temperature nleasuring apparatus according to an embodiment of the
present invention \\rill be described belowv. First, an overview of the surface temperature
measuring apparatus according to this embodin~enwt ill be described.
20 [0027]
The surface temperature measuring apparatus according to this en~bodin~ent
includcs a radiation therxnotneter configured to detect thermal radiation light emitted from
a surface of a temperature tneasuretnent target tnaterial in a cooling process with water, a
housing having an opening on a temperature nlcasurement target material side, tlte housing
25 storing, in an inside of the housing, at least a light receiving unit of the radiation
tliemotneter among structural elenients of the radiation thermometer, and an optical glass
that is fit and sealed in the inside of the l~oousing bctwcen the tenlperature measurenlent
target nlaterial and thc light receiving unit of the radiation thern~ometcl; the optical glass
being configured to transmit the thern~al radiation light. Further, an end surface of the
optical glass on the tenlperature measurement target nlaterial side is adjacent to the surface
5 of the temperature n~east~retnetnatr get material.
[0028]
In the surface temperature measuring apparatus according to this emboditnent, the
housing has the opening on the tenlperature measuretnent target material side and stores, in
the inside of the housing, at least the light receiving unit of the radiation thennometer
10 anlong structural elenlents of the radiation tl~ermon~etel: Further, the optical glass that is
interposed between the temperature nleasurenlent target material and the light receiving
unit of the radiation thermometer transmits the thermal radiation light. Accordingly, the
thermal radiation light emitted from the surface of the temperature measurement target
material is received by the light receiving unit of the radiation thermometer through the
15 opening of the housing and the optical glass. Note that the entire radiation thermometer
may be stored in the honsing, or the light receiving unit of the radiation thermometer may
be stored in the housing and the structural elements other than the light receiving unit of
the radiation thernlometer may be provided outside of the housing.
[0029]
20 In general, in a cooling process, there is water vapor or scattered water on the
periphery of the tenlperature ~~leasurementatr get material. Accordingly, the water vapor
or the scattered water may absorb or scatter the radiant energy, which may result in a
decrease in the radiant energy of the thennal radiation light detected by the radiation
thernlometer and the generation of an error in the nleasmement (hereinafter also referred to
25 as tneasurement error). It is possible to reduce the effects of the water vapor and the
scattered water if the radiation therlnometer is installed adjacently to the temperature
ineasurcinent target material; l~owevel; in this case, tlle heat resistance or waterproof
property of the radiation tl~ernlometer inay be inatter. In the surface temperature
meast~ringa pparatus according to this embodiment, the optical glass is fit and sealed in the
inside of the housing between the temperature measurement target material and the light
5 receiving unit of the radiation thernio~neter. Accordingly, the radiation ther~noineter is
prevented from being directly subjected to heat emitted fiom the temperature ineast~rcnlcnt
target material, and water is unlikely to enter the inside of the housing throogli the end of
the opening of the housing and the light receiving unit of the radiation tllertnometet
Therefore, it is possible to secure the heat resistance and waterproof property of the
10 radiation tliermotneter.
[0030]
Further, since the end surface of the optical glass on tl~tee mperature rneasurenlent
target material side is adjacent to the teniperature measurement target material, water vapor,
scattered water, and cooling water are unlikely to enter a space between the surface of the
15 teniperature measure~nent target material and the end surface of the optical glass on the
tenlperature measurement targct material side. Further, even when cooling water and the
like enter, the cooling water entering the space between the surface of the tetnperature
nieasure~nent arget material and the end surface of tlie optical glass on the temperature
measurement target material side will have a surface tension so as to be kept steady in this
20 space. Accordingly, it becomes possible to reduce temperature ineasureinent errors
caused by absorption or scattering of the radiant energy by water vapor or scattered \vatel:
[003 11
Here, the state in \vIiich tlie cooling water kept steady in the space betwecn the
surface of the temperature nleasure~nenta rget material and the end surface of the optical
25 glass on the temperature nleasurenlent targct inaterial side includes not only the state in
\vl~iclt~h e cooling water is coinpletely charged in the space between the surface of the
te~nperature rneasure~nent target material and the end surface of the optical glass on the
te~nperature~ neasurement arget material side but also the state in which the cooling water
is kept steady in a part of the space between the surface of tlie temperature measure~nent
target ~naterial and the end surface of the optical glass on the temperature measure~nent
5 target material side. Specificallj: for example, in a case in which the surfacc of the
temperature measurement target material that dctccts the tliernlal radiation light is a plane
vertical to the horizontal direction, the cooling water is affected by gravity. I11 this case,
the cooling water can be kept steady below the space between the surface of the
te~nperature measurement target material and the end surface of the optical glass on the
10 te~nperaturem easurenlent target material side.
[0032]
Accordingly, the surface temperature measuring apparatus may be configured in a
tnanner that the end surface of the optical glass on the temperature measurement target
material side is located at a position where water is present in the space between the end
15 surface of the optical glass on the temperature measurement target material side and the
surface of the temperature measuretnetlt target ~nateriala nd the light receiving unit of the
radiation thennometer receives tlie thermal radiation light emitted from the surface of the
temperature ~neasurement target lnaterial though the water that is prescllt in the space
between the surfacc of the telnperature measurement target tnaterial and the end surface of
20 the optical glass on tlie telnperature measurement target material side. Accordingly, it
beco~nes possible to reduce temperature measurement errors caused by absorption or
scattering of the radiant energy by water vapor or scattered water.
[0033]
Fu~ther, with the surface tenlperature measuring apparatus according to this
25 embodiment, it can be expected that the cooling water is kept steady in the space between
the surface of the temperature ~neasurement target material and the end surface of the
optical glass on the tenlperatnre measurement target material side. Accordinglj: the
surface telnperature measuring apparatus according to this enlbodirile~lt can reduce
temperature measurement errors caused by absorption or scattering of the radiant energy
by water vapor 01. scattered water without the use of purge water or purge air. Furthel; a
5 temperature decrease of the temperature nleasurement target nlaterial caused by spraying
the purge water or the purge air on the tenlperature measurement target material is not
generated, so that tlie surface temperature of the tenlperature measurement target material
is hardly affected.
[0034]
10 For example, in a cooling process of a wheel having a substantially circular cross
section, the outer peripheral surface (side surface in the circunlferential direction) of tlle
wheel is cooled by water while the wheel is rotated around the axis center. In this case, in
order to check whether or not cooling is pcrfornled under management of appropriate
temperatures, the temperature of the outer peripheral surface of the wheel is nleasured by a
15 radiation thennometer. In pal-ticulal; if purge water or purge air is used in measuring the
temperature of the wvl~eel, since the rotation speed of tlie wheel is low, a temperature
decrease of the wheel caused by the purge water or tlie purge air becomes obvious, and it
becomes dificult to realize a desired cooling process. Further, since the temperature of
the same side surface is measured every time the wheel rotates once, the tenlperature
20 decrease of tlie wheel caused by the purge water or the purge air is gelicratcd plural times,
and accordingly, it becolnes nlore difficult to realize a desired cooling process. With thc
surface temperature measuring apparatus according to this embodiment, since the surface
of the wheel is not cooled by the purge water or the purge air, the surface temperature of
the wlieel can be measured without damaging the representativeness of the nleasured
In this embodinlent, it is prcferable that the radiation ther~no~netedre tects light
having any one of wavelength bands of 0.7 to 0.9 pm, 1 .O to 1.2 Inn, and 1.6 to 1.8 ~uni.
[0036]
FIG. 5 is a graph showing the relation between the wavelength of the thcrmal
5 radiation light and the transmittance thereof with respect to tap water at 28 "C having
various thicknesses. From FIG. 5, it is found that the tra~lslllittanceb ecomes higher as the
thickness of \vater is larges. Here, in this elllbodimcnt, the end surface of the optical glass
on the temperature tneasure~nent target material side is adjacent to the surface of the
temperature measurement target material. For example, when the gap between the
10 surface of the temperature lneasurcmcnt target material and the end surface of the optical
glass on the temperature measurement target tnaterial side is set to 3 tnm or shorter, the
transmittance of the thermal radiation light serving as a cause of a temperature
measurement error may be higher than the transmittance shown in a case in which the
thickness of water is 3 mm.
15 [0037]
On the other hand, the cooling water is not always charged conipletely in a
measurement field of the radiation thermometer because the charge state of the cooling
water changes when the measured position of the surface temperature moves, for example.
That is, in a case in ~vliichth e detected thertl~alr adiation light does not pass through the
20 cooling water, the transmittance fluctuates substantially.
[0038]
As sl~o\vnin FIG. 5, in a case of using a radiation ther~llometcrw ith detection
~vavelengthso f 0.7 to 0.9 pn~w, hen the thickness of water is 3 111111, the transmittance is
approximately 1 .O. In this case, even wvl~en the change of the charge state of the cooling
25 water is taken into consideration, the transmittance hardly fluctuates, and accordingly,
measuremeat errors arc hardly generated.
[0039]
Further, in a case of using a radiation thermotneter with detection wavelengths of
1.0 to 1.2 lutn, when the thickness of water is 3 mtn, the transmittance is 0.7 or higher.
Accordingly, when the charge state of the cooling water that is present in the space
5 between the surface of the temperature measurement target material and the end surface of
the optical glass on the temperature measuretnent target material side changes, the
translnittance fluctuates between 0.7 and 1.0. When it is assumed that 0.85, which is the
intermediate value therebetween, is the average transmittance, the transtnittance fluctuation
range is 0.15. From this value, the effect of the transmittance fluctuation range on the
10 measured temperahe is calculated to be approximately *9 "C in the 600 O C region and
approximately *5 'C in the 400 OC region. Accordingly, even when the charge state of the
cooling water changes, the surface temperature can be measured accurately.
[0040]
Further, in a case of using a radiation thernlometer with detection wavelengths of
15 1.6 to 1.8 pm, when the thickness of water is 3 mm, the transmittance is 0.1 or higher.
Accordingly, when the charge state of the cooling water that is present in the space
between the surface of the temperature measuretnent target material aud the end surface of
the optical glass on the temperature measurement target material side changes, the
transmittance fluctuates between 0.1 and 1 .O. When it is assumed that 0.55, which is the
20 intermediate value therebet\veen, is the average transmittance, the translnittance fluctuation
range is 0.45. From this value, the effect of the transmittance fluctuation range on the
tneasured temperature is calculated to be approxitnately rt24 OC in the 400 "C region and
approximately i12 "C in the 200 "C region. Accordingl~~ev, en when the charge state of
the cooling water changes, the surface temperature of the temperature measurement target
25 material call be ~neasured accurately.
[0041]
According to the above preferred configuration, the radiation tliertno~neterd etects
light having waveletigth bands at which the transmittance of the thernlal radiation light is
high with respect to tlie water that is present in the space between the surface of the
tcnlperature measuretnent target material and the end surface of the optical glass on the
5 temperature measurement target nlaterial side, and accordingl>: measurenlent errors can be
suppressed.
[0042]
In this enlbodimcnt, it is preferable toy include a keeping member configured to
keep the gap between the surface of the temperature tmeasurement target material and the
10 end surface of the optical glass on the temperature tneasuren~ent target tnaterial side
substantially constant.
[0043]
Accordit~gto the preferred configuration, since the gap between the surface of the
temperature measurement target material and the end surface of the optical glass on the
15 temperature measuretnent target material side is kept, the optical glass does not contact the
temperature measurement target material. Accordingly, the optical glass can be prevented
fro111 being damaged by contacting the temperature measurement target material. Further,
since the gap is kept substantially constant, the transmittance does not fluctuate by the
change of the thickness of water. Accordingly, tlie surface temperature of the temperature
20 measurement target tnaterial can be measured more accurately.
[0044]
Further, the growth of the scale to a wl~ecol r the like generates unevenness on the
surface of the ~vheela, nd accordingly, the surface of the wheel may contact the end surface
of tlie optical glass, whicl~ may damage the optical glass. According to the above
25 preferred configuration, since the gap between the surface of the wheel and the end surface
of the optical glass on the wheel side is kept, the surface of the wheel can be prevented
from contacting the end surface of the optical glass and the optical glass can bc prcventcd
from being damaged. Furthel; as described above, since the gap is kept substantially
constant, the surface tetnperature of the wheel can be measured more accurately. Note
that, as the keeping member, for exa~nplei,t is possible to use a contact roller mechanism
5 including a roller that is attached to a housing and is pressed toward the surface of the
temperature measure~nent arget material so as to be constantly in contact with the surface
of the temperature measurement target material.
100451
In a case in which tlie surface of the temperature measurement target material on
10 ivhiclt the radiation therlnometer detects the thermal radiation light is a plane that is
substantially vertical to the horizontal direction, it is preferable that a measured
temperature value is calculated by correcting an output value of the radiation thermometer
by use of tlie transmittance of the thertnal radiation light with respect to the thickness of
water corresponding to a length that is substantially half of tlie gap between the surface of
15 the telnperatore measurement target tnaterial and tl~cen d surface of the optical glass on the
temperature measurement target material side.
[0046]
According to the preferred configuration, the outlx~t value of the radiation
thermometer is corrected by use of the transmittance of the thermal radiation light with
20 respect to the thickness of water corresponding to a length that is substantially half of the
gap between the surface of the temperature measurement target material and the end
surface of the optical glass on the temperature lncasurelnent target material side. That is,
the output value of tlie radiation tl~emometer is corrected by estimating, as the
transmittance of tlie therlnal radiation light with respect to the thickness of water
25 corresponding to a length that is substantially half of the gap between the surface of the
temperature measurement target material and the elid surface of tlie optical glass on the
te~iiperature ~iieasuretiient target tnaterial sidc, the average value of fluctuation of
transmittance due to the change of the charge state of the water that is present in the space
between the surface of the temperature ~ileasurenient target tiiaterial and the end surface of
tlie optical glass on the te~iiperaturem easurement target material side. Accordingly, the
5 surface teniperature of the temperature measurement target material can be measured easily
and accurately.
[0047]
In a case in wliicli the surface of the temperature measurement target tnaterial on
which the radiation tl~ermorneterd etects tlie tllermal radiation light is the top surface of tlie
10 temperature measurement target ~naterial that is substantially parallel to the horizontal
direction, it is preferable that the gap between the surface of the temperature measuren~ent
target tnaterial and the end surface of the optical glass on the temperature measure~nent
target material side is 2.5 tntn or slio~ter.
[0048]
15 According to the preferred configuration, the surface of the temperature
~neasureriient target material on which the radiation tl~ernlometer detects the thermal
radiation light is the top surface of the tetnperature lileasurenient target tiiaterial that is
substantially parallel to the horizontal direction, and the gap between tlie surface of tlie
temperature measurement target material and the end surface of the optical glass on the
20 temperature iiieasuretnent target material side is 2.5 mm or shorter. Accordingly, a
surface tension is generated in a ~lia~lntehra t the cooling water is charged in substantially
the entire space between the surface of tlie teniperature nleasurelnent target material and
the end surface of the optical glass on tlie tetiiperature ~ileasurenient target material side.
Accordingly, the transmittance of the tlier~nal radiation light does not fluctuate by tlie
25 change of the charge state of water, tlie transnlittance of the thermal radiation light
depending on tlie thickness of water becotnes s~~bstantiallcyo nstant, and the surface
temperature of the temperature ~neasure~netnatr get nlaterial can be measured with a high
accuracy.
[0049]
In a case in which the surface of the temperature measurement target material on
5 which the radiation thernlometer detects the themla1 radiation light is a plane that is
substantially vertical to the horizo~itald irection, it is preferable that the light receiving unit
of the radiation tlermo~neterr eceives the thermal radiation light emitted through the water
that is present in the space between the surface of the temperature measurement target
material and the end surface of the optical glass on the temperature measurement target
10 material side, and that the gap between the surface of tlie temperature nieasure~nent arget
material and the end surface of the optical glass on the temperature measurement target
material side is 1.0 mm or shorter.
[0050]
According to the preferred configuration, the surface of the temperature
15 tneasuretnent target material on mrllicli the radiation thermometer detects the thern~al
radiation light is a plane that is substantially vertical to the horizontal direction, and the
cooling water that is present in the space between the surface of the temperature
measusenlent target material and the end surface of the optical glass on the te~nperature
measurement target material side is affected by gravity. In this case, since the gap
20 between the surface of the temperature measurelnent target material and the end surface of
the optical glass on the tetnperature nleasurclncnt target material side is 1.0 nun or slioortcr,
a surface tension is generated in a malltier that the cooling water is charged in a range
corresponding to an area of substautially 60 % or more of the entire area of the end surface
of the optical glass on the temperature measurement target material side, the area being
25 below the end st~rface. Accordingly, the light receiving unit of tl~era diation thermometer
receives the thermal radiation light emitted tlxougll the water that is present in the space
between the surface of the tenlperature measurement target material and the end surface of
the optical glass on the temperature measurement target material side. In other words, the
light receiving unit of the radiation thertnometer receives the thermal radiation light that is
transmitted through a part where the cooling water is charged. Accordinglj: the
5 transmittance of the tllern~al radiation light depending on the thickness of water beconles
substantially constant, and the surface temperature of the temperature ineasurernent target
nlaterial can be measured with a high accuracy.
[005 11
In this embodiment, it is preferable that a water supply apparatus configured to
10 supply water to the space between the surface of the temperature measure~nent target
material and the end surface of the optical glass on the te~nperature measure~nent target
material side is provided.
[0052]
According to the preferred configuration, water is charged in the space between
15 the surface of the temperature measurement target tnaterial and the end surface of the
optical glass on the temperature measurement target tnaterial side. Accordingly, the
trans~nittanceo f the thernlal radiation light does not fluctuate by the change of the charge
state of water, and the surface temperature of the tenlperature measurenlent target material
can be measured with a high accnracy.
20 [0053]
Further, in this emboditnent, a method of measuring a st~rfacct enlperature of a
tenlperattlre nleasurement target nlaterial by detecting, by use of a radiation thermometer,
thernlal radiation light emitted fiom a surface of the temperature n~easurement target
nlaterial in a coolitlg process with water is a method of nleasuring the surface tenlperature
25 of the temperature tneasurement target tnaterial by interposing an optical glass configured
to transmit the thermal radiation light between the temperature measurenlent target
material and a light receiving unit of the radiation tl~ennometers o as to prevent water from
entering the space between the optical glass and the light receiving unit of the radiation
thennortlete~; and by locating an end surface of the optical glass on the tenlperaturc
measurement target material side adjacently to the surface of the temperature illeasurenient
5 target material.
[0054]
Further, in a case in which the temperature ~~leasrnemetnatr get nlaterial is a steel
material having a disk shape, a colulnllar shape, or a cylindrical shape having the outer
peripl~eral surface, such as a wheel ha\ing a substantially circular cross section, the
10 temperature of the outer peripheral surface of the tenlperature measurement target material
may be measured. For example, in a cooling process of a wheel, in order to check
whether or not coolittg is performed under n~at~agenienotf appropriate temnperatures, the
temperature of the outer peripheral surface of the wheel is measured by a radiation
themmometer. I11 this mannel; the temperature of the outer peripheral surface of the
15 temperature measurement target material is measured by use of the radiation thennometer
while the gap between the outer peripheral surface of the temperature measurement target
material and the end surface of the optical glass on the temperature lneasurenlent target
material side is kept substantially constant, even in the state in wl~ich the temperature
measurement target material is rotated around the center axis of the tenlperature
20 nteasurcment target material as the rotation center and the outer peripheral surface of the
temperature measurement target material is cooled by water. Accordingly, the
temperature of the outer peripheral surface of the temperature measure1nent target material
call be measured accurately.
[0055]
25 4. Embodiment of surface temperature measuring apparatus>
Next, a surface tenlperature measuring apparatus according to an ernbodimei~t of
the present invention will be described \\lit11 reference to appended draivings by taking as
an example a case in which a temperature measurement target material is a wheel having a
substantially circular cross section. FIG. 1 is a schematic drawing showing a surface
tenlperature ineasurii~ga pparatus 100 according to an e~nbodinlento f the present invention
5 The schematic drawing sl~owvn in FIG. 1 is a plan view of the surface temperature
~lleasuriuga pparatus 100 showing a cross section of the inside of a housi~lg2 . FIG. 2 is a
scllcmatic front view of the surface temperature ineasuring apparatus 100 when seen from
direction A in FIG. 1. FIG. 3 is a schematic side view of the surface temperature
nleasuring apparatus 100 when seen fiom direction B in FIG. 1. As shown in FIG. 1, the
10 surface temperature measuring apparatus 100 accorditlg to this enlbodinlellt includes a
radiation themlometer 1, the housing 2, and an optical glass 3, aild is disposed to be
opposed to a temperature ~neasuretnenta rget material W.
[0056]
The radiation ther~nometer 1 is a ther~llometer that measures temperature by
15 detecting thermal radiation light received by a light receiving unit 11 of the radiation
thernlometer 1.
[0057]
The housing 2 has an opening on the telnperature nleasurenlcllt target material W
side. Further, the housing 2 stores therein at least the light receiving unit 11 of the
20 radiation thermometer 1 among structural elements of the radiation ther~l~omete1r.
[OOSS]
The optical glass 3 is fit and sealed in the inside of the housing 2 between the
temperature ~neasuremellta rget nlaterial W and the light receiving unit 11 of the radiation
therlllomneter 1, and is capable of transmitting the thermal radiation light therethrough.
25 [0059]
The radiation tl~erlllometer 1 includes the light receiving unit 11, optical fibers 12,
and a radiation tl~erlnolileter main body 13. The optical fibers 12 transfer the thermal
radiation light received by the light receiving unit 11 to tlie radiation thernlometer main
body 13. Note that the optical fibers 12 might be damaged when used alone, and
accordingly, are each covered with a stainless stecl flexible hose (not sho\vn). The
5 radiation thermometer maill body 13 perfornls pl~otoelectric conversion 011 tlie thermal
radiation light that is received by the light receiving unit 11 and is transferred by the
optical fibers 12 to convert electric signals into a temperature.
[0060]
In the surface temperature measuring apparatus 100 according to this embodiment,
10 the housing 2 has the opening on tlie temperature measurement target material W side and
stores the light receiving unit 11 of the radiation thermometer 1 in the inside of the housing
2. Furtheel; the optical glass 3 interposed betxveen the temperature measurement target
material W and the light receiving unit 11 of the radiation thermon~eter 1 transmits the
thermal radiation light therethrougli. That is, the thertnal radiation light emitted fro111 the
15 temperature measurement target material W passes througl~th e opening of the housing 2
and the optical glass 3 and is received by the light receiving unit 11 of the radiation
thermo~neter 1. Accordingly, the radiation therlnometer 1 can detect the thermal radiation
light emitted from a surface of the tenlperature measurement target tnaterial W.
[0061]
20 In the surface temperature measuring apparatus 100 according to this embodiment,
the light receiving unit 11 of the radiation ther~nometer 1 and parts of the optical fibers 12
are stored in the housing 2. In order to secure the heat resistance of the radiation
thennometer 1, it is preferable to store only a part of the radiation thermometer 1 in the
housing 2 as in this enlbodin~ent; however, the present invention is not limited to this
25 example, and the entire radiation thermometer 1 may be stored in tlle housing 2.
[0062]
I11 this c~nbodimcnt, the light receiving unit 11 has a circular shape with a
diameter of 5 nlm when seen fiom the direction A in FIG. 1. The light receiving unit 11 is
locatcd at a position where the temperature measuring field on the surface of the
telnperature measurement target material W is approxin~ately1 0 mtn in diameter.
5 [0063]
In this embodiment, the housing 2 has a ring shape in a cross section, specific all^:
a cylindrical shape so as to be easily fit and sealed in tlie optical glass 3 having a
substantially circular cross section, as will be described later. Howe\rcr, the present
invention is not limited to this example, and any of various shapes can be used as tlie shape
10 of the housing 2, such as an elliptic cylindrical shape or a square cylindrical shape,
depending on tlie shape of the optical glass 3.
[0064]
In this embodiment, in order to make tlie optical glass 3 as compact as possible
while securing the temperature measuring field effectively, the optical glass 3 has a
15 substantially circular cross section. Specifically, in FIG. 1 and FIG. 2, the shape of the
optical glass 3 is a columnar shape with a diameter of &om 10 mm to 20 mln and a length
of approximately 100 mtn. By setting the length of the optical glass 3 to approxi~nately
100 mm, the heat resistance and waterproof property of the radiation therrnonlctcr 1 can bc
secured, and it is desirable to set the length of the optical glass 3 to more than five times as
20 long as the diameter of the optical glass 3. Ho\vevel., the present invention is not limited
to this example, and any of various shapes can be used, such as an elliptic columnar shape
or a square columnar shape.
[0065]
In this embodiment, since an end surface of the optical glass 3 on the temperature
25 measurement target lnaterial W side is adjacent to the surface of the telnperature
measurement target material W, water vapol; scattered watel; and cooling water are
unlikely to enter a space between the surface of the tetnperature measurcmcnt target
nlaterial W and the end surface of the optical glass 3 on the temperature n~easurel~lent
target material W side. Further, even when cooling water and tl~cli ke enter, the cooling
water entering the space between the surface of the temnperature mneasurement target
5 material W in a cooling process with water and the end surface of the optical glass 3 on the
temperature measurement target material W side will have a surface tension so as to be
kept steady in this space. Accordingl~~it, becomes possible to reduce temperature
measurement errors caused by absorption or scattering of the radiant energy by water vapor
or scattered water.
10 [0066]
In this embodiment, the shape of the end surface of the optical glass 3 on the
temperature measilreme~lt arget ~naterialW side is planar. Accordingly, even when the
surface shape (curvature) of the temperature measuren~ent target material W changes, the
cooling water entering the space between the surface of the teniperature measurement
15 target material W and the end surface of the optical glass 3 on the temperature
measurement target material W side will easily have a surface tension averagely.
However, the present invention is not limited to this example, and the shape of the end
surface of the optical glass 3 on the temperature n~easuren~entatr get material W side may
be a shape in accordance with the surface shape of the tetnperature measurement target
20 ~natcriaWl .
100671
Specificall): the shape of the end surface of the optical glass 3 on the temperature
nleasurenlent target nlaterial W side nlay be a shape having a substantially constant gap
between the surface of the temperature nleasurenlent target material Wand the end surface
25 of the optical glass 3 on the tenlperature measurement target material W side across the end
surface of the optical glass 3 on the temperature nleasurelnent target material W side.
More specifically, the cnd surface of the optical glass 3 on the teniperature measurement
target material W side may have a curvature so as to be concentric with the surface of the
temperature measurement target material W. In particular, in a case in whicl~th e wl~eela s
the temperature measurement target tnaterial W has a constant outer diameter (in a case in
5 which the temperature measurement target tnaterial W has a constant surface shape), by
forming the shape of the end surface of the optical glass 3 on the temperature nleasurement
target material W side as a shape having a cuivature so as to be concentric with the surface
of the temperature measurement target lnaterial W having the constant outer diameter, it is
considered that the cooling water entering the space between the surface of the temperature
10 rneasuretnent target material W and the end surface of the optical glass 3 on the
temperature measurement target material W side will have the surface tension more easily.
[0068]
The surface temperature measuring apparatus 100 according to this embodiment
further includes sealing members 61 to 64, an optical glass energizing member (not shown),
15 and a stopper 81. The optical glass 3 according to this enlbodinlent is fit and sealed in the
inside of the housing 2 with the sealing nle~nbers6 1 to 64. In this embodiment, as shown
in FIG. 1, the sealing tnenlbers 61 to 64 are fit between the housing 2 and the optical glass
3. Further, in this elnbodiment, of the sealing melilbers 61 to 64, the sealing meiilber 61
that is the closest to the tcmperat~~irnee asurenlent target material W is preferably a metal
20 ring with high heat resistance, fornled fro111 a soft metal such as lead. Meanwhile, the
sealing nlenlbcrs 62 to 64 are each preferably an 0 ring formed fro111 a heat resistant rubber
having a high waterproof property, formed from a resin such as silicon or Teflon
(registered trademark). Accordingly, it becoilles possible to secure the heat resistance and
waterproof property of the radiation thermometer 1 and to suppress damage of the optical
25 glass 3 by impact.
[0069]
The optical glass energizing ~nember is a spring (not shown) provided in the
inside of the housing 2, and energizes the optical glass 3 toward the surface of the
temperature tlleasllremellt target material W. Furtliel; the stopper 81 is locked at the end
of the optical glass 3 on the temperature measurement target material W side so that the
5 optical glass 3 should not be extruded out of the housing 2. Accordingly, the optical glass
3 is fixed firmly between the optical glass energizing ~nembcr and the stopper 81, and
accordingly, it becomes possible to prevent the optical glass 3 from being moved by impact
to contact the housing 2 or the radiation thermometer 1 to be damaged, and to prevent the
radiation thermometer 1 from being damaged.
10 [0070]
In this embodiment, as a preferred embodiment, the radiation tl~ennometer 1
detects light having any one of wavelength bands of 0.7 to 0.9 pm, 1.0 to 1.2 ptn, and 1.6
to 1.8 pm. Specifically, the radiation thermometer rnain body 13 includes a Si photodiode
or an InGaAs photodiode as a detector that performs photoelectric co~i\rersion on tlie
15 thermal radiation light transferred by the optical fibers 12 and outputs current in
accordance with the light amount. After amplifying output current from the Si
photodiode or the InGaAs photodiode, the radiation themiotneter ~nainb ody 13 performs
current-voltage conversion and AD conversion and corrects the en~issivity of the
temperature ineasurement target material W to convert electric signals into a temperature.
20 [0071]
Further, the radiation thermometer nlain body 13 i~lcludesa n optical filter that
transmits only light having any one of wavelength bands of 0.7 to 0.9 pm, 1.0 to 1.2 pm,
and 1.6 to 1.8 Lctn between tlie surface of the temperature measuretnent target material W
and the detector of the radiation thermometer 1, more specifically, between the end of the
25 optical fibers 12 on tlie radiatiori tlier~nometerm ain body 13 side and the Si photodiode or
the InGaAs photodiode. Thus, the wavelengtl~ of the thermal radiation light detected by
the radiation thcrmomcter 1 is any one of wavelei~gthb ands of0 .7 to 0.9 /urn, 1.0 to 1.2 lun,
and 1.6 to 1.8 pill. Note that, in a case of using the Si photodiode as the detectol; an
optical filter tliat traiismits only light having any one of wavelength bands of 0.7 to 0.9 prn
and 1.0 to 1.2 11n1 is provided. Further, in a case of using tlie InGaAs photodiode as the
5 detector, an optical filter that transtnits only light having a wavelength band of 1.6 to 1.8
p111 is provided.
[0072]
According to the preferred configuration, as described above, tlie radiation
thermometer 1 detects light having wavelength bands at which the traiisinittaiice of the
10 thermal radiation light is high with respect to tlie water tliat is present in the space between
the surface of the temperature measurement target material W and the end surface of the
optical glass 3 on the temperature measurenient target material W side, and accordingly,
measure-enent cl.l.ors can be suppressed.
100731
15 The optical glass 3 according to this embodinlent is a quartz rod that transmits
near infsared light. Since a quartz rod has high transmittance of light having a
wvavelengtli of 2 ptn or shorter, measurement errors arc hardly generated by absorption or
tlie like oft he thern~alr adiation light by the quarts rod. However, the present invention is
not limited to this exa~nplea, nd an optical glass tliat transmits near infrared light, such as
20 sapphire glass or calciu~nfl uoride (CaF2),m ay also be used as the optical glass 3.
[0074]
As a preferred emboditnent, the surface tenlperature ~neasuring apparatus 100
according to this embodiment includes a keeping ine~nberth at keeps the gap between the
surface of the temperature nleasurenlent target nlaterial W and tlie end surface of tlie
25 optical glass 3 on the temperature nleasurerilent target lnaterial W side substantially
constant. Specifically, the surface temperature n~easuringa pparatus 100 according to this
embodinlent includes, as the keeping inember, a contact roller mechanism 4. As sl~o\vnin
FIG. 1, the contact roller mechanism 4 includes a roller 41, energizing members 42 and 44,
an energizing spring 43, and an air cylinder 45.
[0075]
5 Since the energizing member 42 is attached to the housing 2, when the air cylinder
45 energizes the energizing member 44 to\\rard the temperature measurement target
material W side, the energizing member 42 energizes the housing 2 toward the temperature
measurement target material W side via the energizing spring 43. Thus, the roller 41
provided on the housing 2 is pressed toward the surface of the temperature measure~nent
10 target material W so as to be constantly in contact with the surface of the temperature
measurenlent target material W. That is, the gap between the surface of the temperature
measurement target material W and the end surface of the optical glass 3 on the
temperature measurenlent target material W side is decided depending on the position
where the roller 41 is attached to the housing 2 and the diameter size of the roller 41, and
15 the gap is kept substantially constant. Accordingly, it becomes possible to prevent the
optical glass 3 from being damaged by contacting the temperature measurement target
material W. Furthel; since the transmittance does not fluctuate by the change of the
thickness of water, the surface temperature of the tetnperature measurement target material
W can be measured more accurately. Note that two rollers 41 are provided on the housing
20 2 in this embodiment; howevel; the present in\~ention is not limited to this example, and
tlxee or more rollers may be provided.
[0076]
The temperature measurement target material W according to this embodiment is
a ~vlleel having a substantially circular cross section, as described above. As shown in
25 FIG. 1 and FIG. 3, the surface temperature measuring apparatus 100 is configured to be
capable of measuring the tenlperature of the outer peripheral surface of the wheel by
rolling motion of the roller 41 follo\ving the rotation of tlie \vheel.
[0077]
As slio~vni n this embodiment, in a case in \vliich tlie surface of tlie temperature
measuretnent target material W on which the radiation thermometer 1 detects the thernial
5 radiation light is a plane that is substantially vertical to the horizontal direction, as a
preferred embodiment, tlie surface temperature nlcasuring apparatus 100 according to this
enlbodiment calculates a measured temperature value by cor1,ecting the outpot value of the
radiation thermometer 1 by use of the trans~nittance of the thermal radiation light with
respect to the thickness of water corresponding to a length that is substantially half of the
10 gap between the surface of the temperature nleasurelnent target material W and the end
surface of the optical glass 3 on the temperature Ineasurcnlent target material W side.
[0078]
According to the preferred embodiment, the surface teniperah~re measuring
apparatus 100 corrects the output value of the radiation thermnonieter 1 by use of the
15 transmittance of the thermal radiation light with respect to tlie tliichiess of water
corresponding to a length that is substantially half of the gap between the surface of the
temperature measurement target ~natcrialW and the end surface of the optical glass 3 on
the tenlperah~rem easureme~itt arget material W side. At this time, tlie correction of the
radiation thernlometer 1 is performed by estimating, as tlie transmittance of the thermal
20 radiation light with respect to the thickness of water correspondi~ig to a lcngtb that is
substantially half of tlie gap between tlie surface of the tenlpcrature measure~nent target
material W and the end surface of the optical glass 3 on the temperature measurement
target material W side, the average value of fluctuation of tra~isnlittanced ue to the change
of the charge state of the water that is present in the space between the surface of the
25 temperature measuremnent target Inaterial W and the end surface of the optical glass 3 on
the temperature nleasurenlent target material W side.
[0079]
FIG. 6 is a graph showing results of observation of the charge state of the \\later
that is present between a steel sheet and an end surface of the optical glass 3 by the gap
between the top surface (horizontal plane) of tlie steel sheet that is substantially parallel to
5 tlie horizontal direction or tlie plane (vertical plane) of the steel sheet tliat is substantially
vertical to the l~orizontald irection and the end surface of tlie optical glass 3. Specifically,
the optical glass 3 has a colutnnar shape with a diameter of 10 mm or 20 mm. As shown
in FIG. 7, the water tliat is present between the steel sheet and the end surface of the optical
glass 3 is imaged by a camera when the gap clianges, and, as a charge rate, a range of the
10 imaged outline of water occupying the measurement field of the light receiving unit 11 of
the radiation thermometer 1 on the end surface of the optical glass 3 is measured. As for
each of the horizontal plane and the vei-tical plane, charge rates of water are measured thee
times in tlie set gap, and FIG. 6 shows average values of the measured charge rates of
water.
15 [0080]
As shown in this embodiment, in a case in which the surface of the temperature
measurement target niaterial W on which the radiation therniotneter 1 detects the thermal
radiation light is a plane that is substantially vei-tical to the horizontal direction, as a
preferred embodiment, the light receiving unit 11 of the radiation thcrmomcter 1 receives
20 the thermal radiation light eniitted through the water that is present in the space bctween
the surface of the temperattire ~lieasurellicntt arget n~aterialW and tlie end surface of the
optical glass 3 on the temperature measusenlent target material W side, and the gap
between the surface of the temperature nieasurement target material Wand the end surface
of the optical glass 3 on tlie teniperatnre ineasnrernent target material W side is set to 1.0
25 niln or shorter.
[008l]
As shown in FIG. 6, on the \rc~-tical plane of the steel sheet, the water that is
present between the steel sheet and the end surface of the optical glass 3 is affected by
gravity. Accordingly, in a case in whicli the gap is 1.0 nun or shorter, a surface tension is
generated in a manner that water is charged in a range eorrcsponding to an area of
5 substantially 60 % or more of the entire area of the end surface of the optical glass 3, the
area being below the end surface. That is, according to the preferred embodiment, a
surface tension may be generated in a manner that the cooling water is chargcd in a range
corresponding to an area of substantially 60 % or more of the entire area of the end surface
of the optical glass 3 on the tcmperah~re measurement target material W side, the area
10 being below the end surface. Accordingly, when the light receiving unit 11 of the
radiation thernto~neter 1 receives the thermal radiation light transmitted through a part
where the cooling water is charged, the transmittance of the thermal radiation light
depending on the thickness of water becomes substantially constant, and the surface
temperature of the temperah~re measuretilent target material W can be tneasured with a
15 high accuracy.
[0082]
FIG. 8 sllows an example of the relation between the charge rate of water and the
tenlperature measurement error, I11 the example in FIG. 8, the temperature of a
temperature measurement target at 500 OC is measured by the radiation tliermometer 1 \tit11
20 detection wavelengths of 1.0 to 1.2 / ~ m . Let us assume that the measurement field of the
light receiving unit 11 of tlie radiation ther~l~omete1r is substantially equal to the outer
diameter of the optical glass 3 on the end surface of the optical glass 3, as sho\vn in FIG. 7.
I11 this case, the charge rate of the water that is present between the surface of the
temperature lneasurenlent target and the end surface of tlie optical glass 3 on the
25 tenperature measuren~ent target side with respect to the lneasurenient field of the light
receiving unit 11 is changed, so that temperature nleasurement errors of the radiation
thcrnlon~etera re calculated. From FIG. 8, it is found that tlie temperature nleasurelnent
errors decrease as tl~cc harge rate of water increases. When the charge rate of water is
60 % or higher, the temperature measurement errors can be suppressed to be within 3 "C.
[0083]
5 Note that it is not necessary that the measurement field of the light receiving unit
11 of tlie radiation tliernlometer 1 is substantially equal to the outer diameter of the optical
glass 3 on the end surface of the optical glass 3. For example, as sl~ownin FIG. 9, the
lneasure~nentf ield of the liglrt receiving unit 11 of the radiation thermometer 1 may be set
to be smaller than the outer diameter of the optical glass 3 on the end surface of the optical
10 glass 3. Accordingly, it beconles possiblc to set the ~neasurement field of the light
receiving unit 11 of the radiation tliennotneter 1 as the part where water is charged, even
wl~entl le part is small with respect to tlie area of the end surface of the optical glass 3, and
as the charge rate of water where the temperature measurelncnt errors are within a
predetermined range.
15 [0084]
On the other hand, unlike in this embodiment, in a case in which the surface of the
temperature nleasure~nenta rget tnaterial W on which the radiation tl~ermometer1 detects
the thermal radiation light is the top surface of the temperature measurement target
material W that is substantially parallel to the liorizontal direction, it is preferable that the
20 gap betwveen the surface of the tenlperature measurement target material W and the end
surface of the optical glass 3 on the tenlperature ~neasurementa rget material W side is 2.5
tnnl or shorter.
[0085]
As showvn in FIG. 6, on the horizontal plane of the steel sheet, it is found that, in a
25 case in wliic11 tlie gap is 2.5 mm or shortel; a surface tension is generated in a manner that
water is charged in substantially the entire space betwcen the steel sheet and the end
surface of the optical glass 3. That is, in the preferred configuration, the cooling water
may be charged in the space between the surface of the temperature llleasurelnent target
material W and the end surface of the optical glass 3 on the temperature measurement
target material W side. Accordingly, the transmittance of the thermal radiation light does
5 not fluctuate by the change of the charge state of water, the transmittance of the thermal
radiation light depending 011 the thickness of water (transmittance in a case in which the
tl~icknesso f water is the gap) beconles substantially constant, and the surface temperature
of the temperature nleasurement target material can be measured with a high accuracy.
[0086]
10 The surface temperature measuring apparatus 100 according to this elnbodiment
may include a water supply apparatus 5. As shown in FIG. 3, the water supply apparatus
5 according to this embodiment is disposed outside the housing 2 so that water can be
supplied to the space between the temperature measurement target ~naterialW and the end
surrace of the optical glass 3 on the temperature measurement target material W side.
15 That is, by suppletnent of water by the water supply apparatus 5, water is charged in the
space between the temperature lneasuretnent target material W and the end surface of the
optical glass 3 on the tenlperature measurement target material W side. Accordingly, the
transmittance of the thermal radiation light does not fluctuate by the change of the charge
state of water, and the surface temperature of the tenlperature nlcasurenlent target ~uaterial
20 W can be nleasured with a high accuracy.
[0087]
As a preferred embodiment, the surface temperature measuring apparatus 100
according to this e~nbodiment further includes a purge mechanism 7. FIG. 4 is a
schematic diagram of the purge mechanism 7 in the inside of the housing 2. As shown in
25 FIG. 1 and FIG. 4, the purge mechanism 7 according to this embodiment is constituted of
an air nozzle 71 and a hose 72. Tl~eai r nozzle 71 is disposed in the inside of the hose 72.
Furtl~ert,l ie air nozzle 71 and the hose 72 are inserted to the inside of the housing 2.
[0088]
The air nozzle 71 ejecting purge air to the inside of the housing 2 can prevent
water from entering the inside of the housing 2 and make a space on the periphery of tlie
5 of the light receiving unit 11 of the radiation thermometer 1 stored in the inside of the
housing 2 have a clean atmosphere. Accordingly, it becomes possible to prevent
measurclnent errors fsom being generated by a change of a measurement region where the
temperature is measured due to condensation on the light receiving unit 11. The hose 72
also conlmunicates with the outside of the housing 2. Since the tenlperature measuretnent
10 target ~iiaterial W side of the housing 2 is fit and sealed in the optical glass 3, purge air
ejected fs0111t he air nozzle 71 is released outside thsougl~th e hose 72.
[0089]
Note that there is no particular limitation on the kind of purge air as long as the
purge air is a colorless gas that does not shield the themla1 radiation light, such as dry air
15 or nitrogen. Further, there is no pasticular limitation on the purge system as long as the
clean atmosphere can be maintained.
[0090]
FIG. 10 is a scl~en~atdiica gram showing an experimental apparatus for evaluating
the accuracy of surface temperature measurement on a \re~ticalp lane of a steel sheet in a
20 cooling process with water. Specifically, as sl~o\mlin FIG. 10, a heater 92 is disposed in
an airtight container 90. The airtight container 90 has a quartz window 94 on a
temperature measurement plane. The surface temperature measuring apparatus 100
according to this embodiment is disposed in a manner that the gap between the surface of
the quartz window 94 and the end surface of the optical glass 3 is 1 nm. Further, the
25 temperature in the airtight container 90 can be measured precisely by a tl~ertiiocouple 96
disposed in the airtight container 90.
[0091]
FIG. 11 is a graph sho\ving temperature n~easurenlent results obtained by tlie
surface temperature measuring apparatus 100 before and after water is sprayed on the
quartz window 94 froln a water nozzle 98 after the heater 92 of the experi~nentala pparatus
5 shown in FIG. 10 is heated and the temperature in the airtight container 90 is increased to a
predetemiined temperature. As sho~vn in FIG. 11, before water cooling is started, the
telnperature ~neasurernent results show temperatures that are substantially equal to those
measured by the therniocouple 96. After water cooling is started, the tenlperature
measurement results show a temperature measuselllent error of a decrease of
10 approxitnatcly 4 "C from the temperature measured by the therniocouple 96. Since water
is charged steadily in the space between the surface of the quartz window 94 and the end
surface of the optical glass 3, the transmittance of the thermal radiation light niay affect the
thickness of watel; which is 1 mm, and the decrease of approximately 4 "C may be caused
in temperature measurement. That is, nrl~enth e output value oft he radiation thermometer
15 1 is corrected by use of the transmittance of the tlier~nal radiation light with respect to the
thickness of water and tlie measured tenlperature value is calculated, tlie temperature can
be measured with a high accuracy.
[0092]
Note that the tenlperature measurement results obtained by the surface
20 tenlperature measuring apparatus 100 vibrate largely during the water cooling because
variations are generated by the charge state of the water that is present between tlie surface
of the quartz window 94 and the end surface of the optical glass 3. However, the
vibration degree in the temperature measurement results is approxi~nately 3 O C . Even
when this vibration degree is taken into consideration, thc temperature tneasurelnellt results
25 can be obtained with a tenlperature measure~nent error of a decrease of approximately 3 to
6 "C fro111 the tenlperature measured by the tl~ern~ocoupl9e6 , which can be said to be
accurate temperature measurement. Further, when the nleasured temperature value is
calculated by obtaining the average value of this vibration degree, the temperature can be
measured with a high accuracy.
100931
5 The present invention is not limited to the configurations according to the
above-described embodiment, and various modifications are possible without departing
from the scope of the present invention. For example, although the above embodinlent
has shown a case in which the temperature nleasurement target material W is a wheel, the
tenlperatore measurement target material W may be a steel pipe, steel sheet, or the like
10 without limitation.
[0094]
Further, in the above-described embodiment, although the optical glass 3 is fit and
sealed in the inside of the housing 2, the present invention is not limited to this example.
For example, as a nlodification example of the optical glass 3 according to this
15 embodiment, the optical glass 3 may be interposed between the temperature measurement
target material W and the light receiving unit of the radiation tl~ermon~ete1r so as to
prevent water from entering the space between the optical glass 3 and the light receiving
unit 11 of the radiation thennometer 1. Specificallj: for example, the optical glass 3 may
be a long optical glass extending in the direction vertical to the horizontal plane (the
20 direction vestical to the thennal radiation light enlitted from the temperature measurenlent
target material W to the light receiving unit 11 of the radiation thermometer 1).
Accordi~~gleyv, en with a configuration in \vl~icht he light receiving unit 11 is stored in the
inside of the housing 2 and the optical glass 3 is not fit and sealed in the inside of the
housing 2, water may be unlikely to enter the space between the optical glass 3 and the
25 light receiving unit 11 of the radiation therlnometer 1.
[Reference Signs List]
[0095]
1 radiation tl~ermonleter
2 housing
3 optical glass
4 contact roller mechanism
5 water supply apparatus
7 purge illechanism
11 light receiving unit
12 optical fiber
13 radiation thermometer main body
41 roller
42,44 energizing ine~nber
43 energizing spring
45 air cylinder
61 to 64 sealing member
71 air nozzle
72 hose
W temperature measurenlent target material

Name of Docutnent] CLAIMS
[Claim 1]
A surface temperature measuring apparatus comprising:
a radiation thennometer corlfigured to detect thermal radiation light emitted fro111
5 a surface of a temperature measurement target material in a cooling process with water;
a housing having an opening on a temperature measurement target ~naterial side,
the l~oousing storing, in an inside of the housing, at least a light receiving unit of the
radiation thel-nnon~etear ntong st~ucturael lements of the radiation thermometer; and
an optical glass that is fit and scaled in the inside of the housing between the
10 temperature measurement target material and the light receiving unit of the radiation
thennometer, the optical glass being configured to transmit the thennal radiation light,
wherein the optical glass has, on the temperature measurement target inaterial side,
an end surface that is adjacent to the surface of the temperature measurenient target
material.
15 [Claims 2]
The surface temperature nieasuring apparatus according to claim 1,
wherein the end surface of the optical glass on the temperature measuren~ent
target material side is located at a position where water is present in a space between the
end surface of the optical glass on the temperature measurement target material side and
20 the surface of the temperature measurement target material, and
wherein the light receiving unit of the radiation thermometer receives the tl~ermal
radiation light emitted from the surface of the temperature nleasurenlcllt target material
tluough water that is present in the space between the surface of the temperature
measurement target niaterial and the end surface of the optical glass on the temperature
25 measurement target material side.
[Claim 3]
The surface te~ilperature~ lleasuri~alpgp aratus accordi~lgto claim 1 or 2,
wherein the radiation tltennonteter detects ligltt ltaving any one of wavelength
bards of 0.7 to 0.9 ptn, 1.0 to 1.2 pm, and 1.6 to 1.8 pnl.
[Claim 4]
The surface tempe~.aturem easuring apparatus according to any one of clai~tts1 to
3, comprising:
a keeping member configured to keep a gap between tlte surface of the
temperature measurentent target ~naterial and the end surface of tlte optical glass on the
temperature nteasurentent target material side substantially constant.
[Claim 5]
Tlte surface tentperature tneasuring apparatus according to claim 4,
wherein the surface of the temperature measurentent target material on which the
radiation thermometer detects the themla1 radiation light is a plane that is substantially
vertical to a horizontal direction, and
wherein a measured temperature value is calculated by correcting at1 output value
of the radiation tlterntotneter by use of a transmittance of the thermal radiation light with
respect to a thickness of water correspo~tdi~ttog a Iengtli that is substantially half of the gap
between the surface of the temperature nteasure~nent arget tnaterial and the elid surface of
tlte optical glass on tltc temperature tmeasurement target tnaterial side.
[Claims 6]
Tlte surface tetilperaturc measuring apparatus according to claint4,
wliereitl the surface of the tentperature measurement target inaterial on ~vlliclit he
radiation tlter~ttometerd etects tlle tlierntal radiation light is a top surface of the temperature
measurement target material that is substantially parallel to a ltorizontal direction, atid
wherein tlte gap between the surface of the temperature measure~itent target
~naterial and the end surface of the optical glass on tlte temperature measurement target
material side is 2.5 rnm or slorter.
[Claim 7]
The surface temperature ~neasuringa pparatus according to claim 4,
wherein the surface of the temperature mcasure~nent target rnaterial on which the
radiation thennometer detects the thermal radiation light is a plane that is substantially
5 vertical to a horizontal direction,
wherein the light receiving unit of the radiation tliennomcter receives the thel.lnal
radiatioti light emitted through the water that is present in the space between the surface of
the temperature meastirement target material and the end surface of the optical glass on the
temperature measurement target material side, and
10 wherein the gap between the surface of the temperature measurement target
material and the end surface of the optical glass on the temperature measurement target
material side is 1.0 lmll or shorter.
[Claim 8]
The surface temperature measuring apparatus according to any one of claims 1 to
15 4, comprising:
a water supply apparatos configured to supply water to the space between the
surface of the temperature measurement target material and the end surface of the optical
glass on the temperature measure~nent arget material side.
[Claim 9]
20 A snrface tc~nperaturen leasuring apparatus comprising:
a radiation tl~er~nolnetceor nfigured to detect thermal radiation light emitted fro111
a surface of a ternperature measure~nenta rget nlaterial in a cooling process with water;
a housing having an opening on a ternperature nleasurelnent target material side,
the housing storing, in an inside of the housing, at least a light receiving unit of the
25 radiation ther~nometear mong structural elements of the radiation thennometer;
an optical glass that is fit and sealed in the inside of the housing between the
tenlperature measurement target material and the light receiving unit of the radiation
ther~llonletert,h e optical glass being configured to transmit the thern~alr adiation light; and
a keeping menlber configured to keep a gap between a surface of the temperature
measurement target material and an end surface of the optical glass on the temperature
5 measurement target material side substantially constant.
[Claim 10]
A surface temperature measuring method of measuring a surface temperature of a
temperature measurenlent target material by detecting, by use of a radiation thermometel;
thermal radiation light emitted froni a surface of the temperature measure~nent target
10 material in a cooling process with water, the method comprising:
interposing an optical glass configured to trans~nit the thermal radiation light
between the temperature measurement target material and a light receiving unit of tile
radiation thermometer; and
locating an end surface of the optical glass on a temperature measuretnent target
15 material side'adjacently to the surface of the temperature nleasurement target material and
measuring the surface temperature oft he te~nperaturem easurement target material.
[Claim 11]
The surface temperature measuring ~lletlioda ccording to clai~tl1 0,
wherein the temperature measurement target material is a steel material having a
20 disk shape, a colutnnar shape, or a cylindrical shape having an outer peripheral surface,
and
wherein, wvl~en measuring the surface teniperature of the temperature
measurement target material, a temperature of the outer peripl~eral surface of the
temperature 1neasure:ement target material is measured by use of the radiation thermometer
25 wvllile the gap between the outer peripheral surface of the temperature lneasurenient target
material and the end surface of the optical glass on the temperature measurement target
material side is kept snbstantially constant, in a state in wvl~ich the temperature
lneasurelnemlt target material is rotated around a center axis of the temnperature
nleasurenlent target material as a rotation center and the outer peripl~eral surface of the
temnperature measurement target nlaterial is cooled by water.