JP6368599B2 - Temperature measuring device - Google Patents

Description

  The present invention relates to a temperature measuring device provided with a thermocouple, and more particularly, to a temperature measuring device that detects the temperature of a reference junction of a thermocouple provided with a temperature measuring contact at a measurement location by a thermistor for the reference contact.

  As a temperature measuring device provided with a thermocouple, a temperature measuring device that detects the temperature of a reference junction of a thermocouple provided with a temperature measuring contact at a measurement location by a thermistor for the reference contact is conventionally known (for example, Patent Document 1). reference).

  In such a temperature measuring device, the temperature of a measurement location is measured as follows.

  FIG. 9 is a schematic configuration diagram showing a basic configuration of a temperature measuring device TMD that detects a reference contact RP of a thermocouple TC provided with a temperature measuring contact MP at a measurement location MS by a thermistor TH for the reference contact. FIG. 10 is a graph showing the thermoelectromotive force characteristics of the thermocouple TC.

  As shown in FIG. 9, the temperature measuring device TMD forms a closed circuit by joining one end of each of two types of metal conductors MC1 and MC2 as a thermocouple TC. Due to the temperature difference Td (see FIG. 10) between the temperature measuring contact MP) and the open portions OP and OP (reference contact RP) at the other end, the thermoelectromotive force Vd (see FIG. Phenomenon (see Seebeck effect) that causes (see FIG. 10) occurs.

  That is, in the temperature measuring device TMD, the junction JN at one end of the thermocouple TC is provided at the measurement location MS as the temperature measuring contact MP, and the thermoelectromotive force Vd generated between the open portions OP and OP at the other end of the thermocouple TC is obtained. To detect. Here, the thermoelectromotive force Vd is a potential difference between the temperature measuring contact voltage Vm (see FIG. 10) at the temperature measuring contact MP and the reference contact voltage Vr (see FIG. 10) at the reference contact RP. Then, the temperature measuring device TMD obtains the temperature difference Td based on the detected thermoelectromotive force Vd based on the thermoelectromotive force characteristics (see FIG. 10) of the thermocouple TC, and the open portions OP and OP at the other end of the thermocouple TC. Is used as a reference contact RP, the reference contact temperature Tr of the open parts OP and OP (reference contact RP) at the other end is detected by the thermistor TH for the reference contact, and the detected reference contact temperatures of the open parts OP and OP (reference contact RP) are detected. By adding a temperature difference Td based on the obtained thermoelectromotive force Vd to Tr, the temperature measuring junction temperature Tm = Tr + Td (see FIG. 10) at the measurement location MS is measured.

  By the way, the installation position where the reference contact RP of the thermocouple TC is installed and the detection position detected by the thermistor TH are usually not completely matched (slightly deviated), and the reference contact of the thermocouple TC. When temperature unevenness (local hot spot) occurs between the installation position where the RP is installed and the detection position detected by the thermistor TH (Tr≈Tr1) (see FIG. 9), the measurement location is increased accordingly. The temperature measuring junction temperature Tm in the MS is erroneously measured (Tm = Tr1 + Td). For example, when the reference contact temperature Tr1 at the detection position detected by the thermistor TH is higher than the reference contact temperature Tr at the installation position of the reference contact RP (Tr <Tr1), the temperature measurement contact at the measurement point MS is correspondingly increased. The temperature (Tm = Tr1 + Td) is measured higher than the original temperature (Tm = Tr + Td). That is, as the temperature difference between the reference contact temperature Tr at the installation position of the reference contact RP and the reference contact temperature Tr1 at the detection position of the thermistor TH increases, the measurement error of the temperature measurement contact temperature Tm at the measurement location MS increases.

  In this regard, Patent Document 1 discloses a configuration that uses a resistance value change accompanying a temperature change of the thermistor in order to enable temperature compensation of the reference junction.

Japanese Patent Laid-Open No. 10-002807

  However, in the configuration described in Patent Document 1, it is necessary to grasp in advance the resistance value change accompanying the temperature change of the thermistor, which complicates the configuration.

  Therefore, the present invention is a temperature measuring device that detects the temperature of a reference junction of a thermocouple provided with a temperature measuring contact at a measurement location by a thermistor for the reference contact, and grasps in advance a resistance value change accompanying a temperature change of the thermistor. Therefore, an object of the present invention is to provide a temperature measurement device that can suppress a measurement error of the temperature measurement junction temperature at a measurement point, while having a simple configuration.

In order to solve the above-mentioned problem, the present invention provides a temperature measuring device for detecting the temperature of a reference junction of a thermocouple provided with a temperature measuring contact at a measurement location by a thermistor for a reference contact, wherein the reference of the thermocouple A control board to which contacts are electrically connected is housed in a housing, the thermistor is provided on the control board, and a ventilation fan is provided and driven to blow air toward the control board above the control board , The lower control board to which the reference contact of the thermocouple is electrically connected among the divided control boards provided by dividing the control board so that the board surfaces are aligned or substantially aligned with each other. the thermistor is provided in the temperature measuring device which is characterized that you drive provided the ventilating fan to blow toward the control board and the lower side of the control board of the upper above the upper side of the control board Offer That.

  According to the present invention, in a temperature measurement device that detects the temperature of a reference junction of a thermocouple provided with a temperature measuring contact at a measurement location by a thermistor for the reference contact, without previously grasping a resistance value change accompanying a temperature change of the thermistor. Therefore, it is possible to suppress the measurement error of the temperature measuring junction temperature at the measurement location while having a simple configuration.

It is the perspective view which looked at the engine generator which concerns on embodiment of this invention from diagonally upward of the front side. It is the perspective view which looked at the engine generator which concerns on embodiment of this invention from diagonally upward on the back side. It is a schematic block diagram which shows the temperature measurement state of the temperature measuring device which concerns on this Embodiment. It is the elements on larger scale which expand and show the reference contact part of the temperature measuring device shown in FIG. FIG. 4 is a partially enlarged view showing, in an enlarged manner, a state in which a ventilation fan is provided so as to blow air toward the control board above the control board in the housing shown in FIG. 3. It is a front view which shows the internal structure of the housing | casing which accommodates a control board. It is a front view of the housing | casing which accommodates a control board. It is a right view of the housing | casing which accommodates a control board. It is a schematic block diagram which shows the basic composition of the temperature measuring device which detects the reference | standard contact of the thermocouple in which the temperature measurement contact was provided in the measurement location with the thermistor for reference | standard contacts. It is a graph which shows the thermoelectromotive force characteristic of a thermocouple.

  Embodiments according to the present invention will be described below with reference to the drawings.

  FIGS. 1 and 2 are perspective views of engine generator 100 according to the embodiment of the present invention, as viewed from obliquely upward on the front side and obliquely upward on the back side, respectively.

  In the present embodiment, a case where the gas engine 300 is applied to the engine generator 100 will be described as an example. In this example, the engine generator 100 is applied to a cogeneration system. The cogeneration system is a system that covers the demand power of a power consuming device (load) by power generation by the engine generator 100 and collects and uses (for example, uses for hot water supply) waste heat generated by the power generation. For this reason, the engine generator 100 is connected to a waste heat recovery unit (not shown) for recovering waste heat (sometimes called an auxiliary unit).

  First, after describing the overall configuration of the engine generator 100, each component of the engine generator 100 will be described. The longitudinal direction (width direction) of engine generator 100 (the left-right direction in FIGS. 1 and 2) is the X direction, and one side in the longitudinal direction X (the right side in the example of FIG. 1 and the left side in the example of FIG. 2). The X1 direction is set, and the other side (left side in the example of FIG. 1, right side in the example of FIG. 2) is the X2 direction. The depth direction of the engine generator 100 is the Y direction, and one side in the depth direction Y (the front side in the example of FIG. 1, the back side in the example of FIG. 2) is the Y1 direction, and the other side (the back side in the example of FIG. 1). The near side in the example of FIG. 2 is the Y2 direction. Further, the vertical direction (height direction) of the engine generator 100 is defined as the Z direction. The longitudinal direction X, the depth direction Y, and the up-down direction Z are the same in FIGS. 3 to 8 described later.

(Engine generator)
In addition to being housed in the package, the engine generator 100 may be installed (for example, installed indoors) without being housed in the package. In FIG. 1 and FIG. 2, the engine generator 100 shows a state before being housed in the package or a state in which it is installed without being housed in the package.

  The engine generator 100 includes a common platform (base) 200, a gas engine 300, a generator 400, an operation panel 500, a control panel 601, and auxiliary machine panels 602 and 603 (see FIG. 2). In the engine generator 100, components such as a gas engine 300, a generator 400, an operation panel 500, a control panel 601, and auxiliary machine panels 602 and 603 are mounted and fixed on a common floor 200. The common bed 200 is configured by welding a plurality of channel steels and the like. The gas engine 300 is disposed from the center position to the other side X2 in the longitudinal direction X on the common platform 200. The generator 400 is disposed on one side X1 in the longitudinal direction X from the position where the gas engine 300 is disposed. The operation panel 500 and the control panel 601 are disposed on one side Y1 (in this example, the front side of the engine generator 100) from the position where the generator 400 is disposed in the depth direction Y. In addition, the auxiliary machine boards 602 and 603 are arranged on the other side Y2 (in this example, the back side of the engine generator 100) from the arrangement position of the generator 400 in the depth direction Y.

(Generator)
The generator 400 includes a generator body 401 and a generator mount 402. The generator body 401 is elastically supported on the common platform 200 by a generator mount 402. Further, the generator body 401 is configured such that a rotor (not shown) is rotatably supported inside a stator (not shown), and a crankshaft (not shown) extending from the engine body 301 of the gas engine 300 is connected to the rotor. ing. As a result, the generator 400 can generate power by receiving the rotational force of the crankshaft in the engine main body 301 by the rotor in the generator main body 401 as the gas engine 300 is operated. Can be supplied to the electrical system.

(Gas engine)
The gas engine 300 includes an engine body 301 and an engine mount 302. The engine body 301 is elastically supported on the common platform 200 by the engine mount 302. The engine body 301 includes a cylinder block 303, a cylinder head 304 attached to the upper part of the cylinder block 303, and an oil pan 305 attached to the lower part of the cylinder block 303. The gas engine 300 may be any as long as it uses gas as fuel, but is not limited to this, and examples include a gas engine using fuel gas such as natural gas, propane gas, or biogas as fuel. it can.

  In the engine body 301, a crankshaft (not shown) extends from the cylinder block 303 to the one side X1 in the longitudinal direction X, and one end of the crankshaft (in this example, the end of the one side X1) is connected to the generator 400. Connected to a rotor (not shown).

  The gas engine 300 further includes a fuel supply system 300a (see FIG. 1), an intake system 300b, an exhaust system 300c, an engine cooling system 300d, an air-fuel mixture cooling system 300e, and a lubrication system 300f (see FIG. 2).

-Fuel supply system-
The fuel supply system 300a includes a fuel gas supply unit (not shown) provided in a waste heat recovery unit (not shown), and a fuel introduction path 306 (specifically, a fuel introduction pipe) (see FIG. 1). The fuel gas from the fuel gas supply unit is supplied to the mixer (not shown) of the intake system 300b through the fuel introduction path 306.

-Intake system-
The intake system 300b includes an air cleaner 311 (in this example, two air cleaners 311a and 311b arranged in parallel), a mixer, an intake path (specifically, an intake pipe) (not shown), and a supercharger 314 (see FIG. 2). ), An intercooler 315 (see FIG. 1), a throttle valve 316 (see FIG. 1), and an intake manifold (not shown). Here, the throttle valve 316 is configured so that the amount of intake of the air-fuel mixture (mixed gas) to the intake manifold is adjusted by controlling the opening degree.

  The air cleaner 311, the mixer and the supercharger 314 are arranged on the one side X1 (the side on which the generator 400 is arranged in this example) from the cylinder head 304 in the longitudinal direction X. The intercooler 315, the throttle valve 316, and the intake manifold are disposed on one side Y1 with respect to the cylinder head 304 in the depth direction Y.

−Exhaust system−
The exhaust system 300 c includes an exhaust manifold 321, an exhaust path 322 (see FIG. 2), and an exhaust silencer 323.

  The exhaust manifold 321, the exhaust path 322, and the exhaust silencer 323 are disposed on the other side Y2 with respect to the cylinder head 304 in the depth direction Y. The exhaust silencer 323 is disposed on one side X1 (the side on which the generator 400 is disposed in this example) from the cylinder head 304 in the longitudinal direction X.

  In the exhaust system 300c, the exhaust gas in which the air-fuel mixture is combusted by the ignition of the ignition plug in the combustion chamber in each cylinder of the engine body 301 is guided to the outside. As a result, the gas engine 300 can generate a rotational force on the crankshaft and obtain an output for operating the generator 400.

  The exhaust gas after combustion reaches the exhaust manifold 321, the exhaust turbine (not shown) of the supercharger 314, and the exhaust silencer 323. An exhaust gas boiler (not shown) provided in a waste heat recovery unit (not shown) is connected to the exhaust silencer 323 via an exhaust path 322. The exhaust gas boiler recovers the heat of the exhaust gas and releases the exhaust gas from which the heat has been recovered to the atmosphere. Thus, the gas engine 300 can allow the user to use the heat recovered by the exhaust gas boiler as a heat source for hot water supply or the like.

-Engine cooling system-
The engine cooling system 300 d is configured to flow cooling water through the water jackets of the cylinder block 303 and the cylinder head 304 of the engine body 301.

  The engine cooling system 300d includes a cooling water introduction path 331 (specifically, a cooling water introduction pipe) and a cooling water extraction path 332 (specifically, a cooling water extraction pipe). The cooling water introduction path 331 is connected to a cooling water supply path (specifically, a cooling water supply pipe) (not shown) provided in the waste heat recovery unit. The cooling water outlet path 332 is connected to a cooling water recovery path (specifically, cooling water recovery piping) (not shown) provided in the waste heat recovery unit. That is, the engine cooling system 300d cools the engine main body 301 by flowing the cooling water supplied from the cooling water supply path to the cooling water introduction path 331 sequentially into the water jacket of the cylinder block 303 and the water jacket of the cylinder head 304. The configuration is such that the waste heat recovery unit returns to the waste heat recovery path via the cooling water extraction path 332. The cooling water recovery path is connected to a heat recovery heat exchanger (not shown) provided in the waste heat recovery unit. Thereby, the gas engine 300 can make a user utilize the heat | fever collect | recovered from the engine main body 301 with the cooling water as heat sources, such as for hot water supply.

-Mixture cooling system-
The air-fuel mixture cooling system 300e is for flowing cooling water through the intercooler 315 of the intake system 300b.

  The air-fuel mixture cooling system 300e also includes a cooling water introduction path 351 (specifically, a cooling water introduction pipe) (see FIG. 1) and a cooling water outlet path 352 (specifically, a cooling water outlet pipe). The cooling water introduction path 351 is connected to a cooling water supply path (specifically, a cooling water supply pipe) (not shown) provided in the waste heat recovery unit. The cooling water outlet path 352 is connected to a cooling water recovery path (specifically, cooling water recovery piping) (not shown) provided in the waste heat recovery unit. That is, the air-fuel mixture cooling system 300e cools the air-fuel mixture by flowing the cooling water supplied from the cooling water supply path to the cooling water introduction path 351 to the intercooler 315, and then collects the cooling water via the cooling water outlet path 352. It is configured to return to the waste heat recovery unit by a route. The cooling water recovery path is connected to a cooler heat dissipation heat exchanger (not shown) provided in the waste heat recovery unit. Thereby, the gas engine 300 can cool the cooling water for intercooler cooling by heat exchange in the heat exchanger for heat dissipation of the cooler.

-Lubrication system-
The lubrication system 300f supplies the lubricating oil stored in the oil pan 305 to each part of the engine, and lubricates and cools these parts. Therefore, the lubrication system 300f includes an oil pump 361 (see FIG. 2), an oil suction path 362 (specifically, an oil suction pipe) (see FIG. 2), and an oil supply path 363 (specifically, an oil supply pipe) (see FIG. 2). 2), an oil filter (not shown), and an oil recovery path 364 (specifically, an oil recovery pipe) (see FIG. 1).

  The oil pump 361 is an electric pump that sucks the lubricating oil stored in the oil pan 305 through the oil suction path 362, and sucks the sucked lubricating oil into each part of the engine through the oil supply path 363. The lubricating oil that has been pumped toward the engine and lubricated and cooled each part of the engine flows down to the oil pan 305 through the oil recovery path 364 and is recovered in the oil pan 305. The oil pump 361 may be a mechanical type that operates by receiving the rotational force of the crankshaft.

(Operation board)
On the front surface of the operation panel 500 (the surface facing the one side Y1 in the depth direction Y), various switches for operation by the operator and various meters are provided.

(control panel)
The control panel 601 constituting the control system includes various electronic devices (circuit boards) including a control device 700 (see FIGS. 3 and 5 to 8 described later) for controlling the operation of each component of the engine generator 100. Etc.) are housed. Specifically, the control device 700 performs various control operations such as operation control of the gas engine 300, operation control of the generator 400, and control of the oil pump 361.

(Auxiliary board)
The auxiliary boards 602 and 603 accommodate electrical devices such as circuit breakers, switches, contactors, and inverters for operating auxiliary machines such as various pumps, various fans, and various electromagnetic valves.

(Temperature measuring device)
Next, temperature measuring apparatus 800 according to the present embodiment will be described below with reference to FIGS. 3 to 8 and 10.

  FIG. 3 is a schematic block diagram showing a temperature measurement state of the temperature measurement device 800 according to the present embodiment. FIG. 4 is a partially enlarged view showing the reference contact RP portion of the temperature measuring device 800 shown in FIG. 3 in an enlarged manner.

  As shown in FIGS. 3 and 4, the temperature measuring device 800 is a reference for a thermocouple 810 (see FIGS. 1 and 3) in which a temperature measuring junction MP (see FIG. 3) is provided at a measurement location MS (see FIG. 3). The temperature of the contact RP is detected by the thermistor 820 for the reference contact. In this example, the measurement point MS is the upstream end 332a (FIG. 1) of the cooling water outlet path 332 (see FIGS. 1 and 3) in the flow direction W1 (see FIG. 3) of the cooling water for cooling the engine body 301. 3), that is, an outlet portion of a water jacket in the engine body 301 (see FIGS. 1 to 3). In this case, the thermocouple 810 can be used as a detection unit (specifically, a water temperature sensor for engine cooling water) that detects the temperature of the cooling water flowing through the engine cooling system 300d. The thermocouple 810 may be used as a detection unit (specifically, a water temperature sensor for the mixture cooling water) that detects the temperature of the cooling water flowing through the mixture cooling system 300e, or the lubricating oil flowing through the lubrication system 300f. You may use as a detection part (specifically oil temperature sensor for lubricating oil) which detects the temperature of this. Thereby, the control device 700 can recognize the temperature of the engine main body 301 by measuring the temperature of the thermocouple 810 in the temperature measuring device 800, and can thus notify the user of the temperature state of the engine main body 301. Further, the thermocouple 810 can be used not only as a detection unit that detects the temperature of the cooling water or the temperature of the lubricating oil, but also as a detection unit that detects the temperature of another measurement location.

  The temperature measuring device 800 includes a thermocouple 810, a reference contact thermistor 820, and a control board 710 constituting a control device 700 (see FIG. 3). Here, the control board 710 is housed in a housing 900 (see FIG. 3). In addition to the control board 710, various electrical devices such as the inverter 910 are housed in the housing 900, and the housing 900 housing these electrical devices forms an auxiliary machine panel 602 (see FIG. 2). Yes.

  The thermocouple 810 uses the Seebeck effect and has two types of metal conductors 811 and 812 (see FIG. 3). In this example, the thermocouple 810 is a K-type thermocouple. Here, the type of thermocouple indicates the type of thermocouple, and is standardized by the Japanese Industrial Standard (JIS), the International Electrotechnical Commission (IEC), and the like. The type of thermocouple is represented by symbols such as “K”, “J”, “T”, “E”, “N”, “R”, “S”, “B” depending on the type of thermocouple. . The K-type thermocouple is a thermocouple using an alloy (chromel) mainly composed of nickel and chromium for the plus leg and an alloy (alumel) mainly composed of nickel for the minus leg.

  One end of each of the two types of metal conductors 811 and 812 is joined to the thermocouple 810, and the other end is electrically connected to the control board 710. That is, a closed circuit of the thermocouple 810 is formed on the control board 710. Thereby, the control device 700 can detect the thermoelectromotive force based on the potential difference detected by the thermocouple 810.

  The thermistor 820 is provided in the vicinity (close position) of the reference contact RP on the control board 710. The thermistor 820 is electrically connected to the control board 710. Thereby, the control device 700 can detect the temperature of the detection position (position near the reference contact RP on the control board 710) detected by the thermistor 820 based on the electrical resistance value detected by the thermistor 820.

  In the thermocouple 810, the control device 700 has a temperature difference Td (see FIG. 10) between the junction JN (see FIG. 3) at one end (temperature measuring contact MP) and the open portions OP and OP (reference contact RP) at the other end. ) To detect the thermoelectromotive force Vd (see FIGS. 4 and 10) generated between the open portions OP and OP at the other end.

  Specifically, in the temperature measuring device 800, the joint JN at one end of the thermocouple 810 is provided as a temperature measuring contact MP at the measurement location MS (in this example, the upstream end portion 332a of the cooling water outlet path 332), and the other end. The thermoelectromotive force Vd generated between the open parts OP and OP is detected. Here, the thermoelectromotive force Vd is a potential difference between the temperature measuring contact voltage Vm (see FIG. 10) at the temperature measuring contact MP and the reference contact voltage Vr (see FIG. 10) at the reference contact RP.

  And the temperature measuring device 800 calculates | requires the temperature difference Td based on the detected thermoelectromotive force Vd by the thermoelectromotive force characteristic (refer FIG. 10) of the thermocouple TC. Note that the thermoelectromotive force characteristics of the thermocouple 810 are stored in advance in a storage unit (not shown). The temperature measuring apparatus 800 uses a thermistor 820 with the open portions OP and OP at the other end of the thermocouple TC as a reference contact RP, and a reference contact temperature Tr (see FIGS. 4 and 10) at the open portions OP and OP (reference contact RP) at the other end. And a temperature difference Td based on the obtained thermoelectromotive force Vd is added to the detected reference contact temperature Tr of the open portions OP and OP (reference contact RP), thereby detecting the temperature measurement contact temperature Tm at the measurement location MS. = Tr + Td (see FIGS. 3 and 10) is measured.

  By the way, in consideration of the fact that the thermocouple 810 is expensive and it is difficult to electrically connect the thermocouple 810 to the control board 710, in this embodiment, the control housed in the housing 900 is controlled. Compensation between the substrate 710 and the terminal block 720 (see FIG. 3) housed in the housing 900 has the same or almost the same thermoelectromotive force characteristics as the two types of metal conductors 811 and 812 of the thermocouple 810. They are electrically connected by conducting wires 811a and 812a. In addition, the connector pair CN that connects the compensating conductors 811a and 812a and the control board 710 also has a thermoelectromotive force characteristic that is the same as or approximately the same as the two types of metal conductors 811 and 812 of the thermocouple 810. Yes. In this example, the connector CN1 (see FIG. 4) on the compensation conductors 811a and 812a side of the connector pair CN is a female connector, and the connector CN2 (see FIG. 4) on the control board 710 side is a male connector. Yes.

  In the present embodiment, the installation position where the reference contact RP of the thermocouple 810 is installed and the detection position detected by the thermistor 820 do not completely match (slightly deviate), and the reference of the thermocouple 810 When temperature unevenness (local hot spot) occurs between the installation position where the contact RP is installed and the detection position detected by the thermistor 820 (Tr≈Tr1) (see FIG. 4), the measurement is made accordingly. The temperature measuring junction temperature Tm at the location MS is erroneously measured (Tm = Tr1 + Td). For example, when the reference contact temperature Tr1 at the detection position detected by the thermistor 820 is higher than the reference contact temperature Tr at the installation position of the reference contact RP (Tr <Tr1), the temperature measurement contact at the measurement point MS is correspondingly increased. The temperature (Tm = Tr1 + Td) is measured higher than the original temperature (Tm = Tr + Td). That is, as the temperature difference between the reference contact temperature Tr at the installation position of the reference contact RP and the reference contact temperature Tr1 at the detection position of the thermistor TH increases, the measurement error of the temperature measurement contact temperature Tm at the measurement location MS increases.

(Ventilation fan)
In this regard, in the present embodiment, a ventilation fan 730 (see FIG. 3) is provided above the control board 710 so as to blow air toward the control board 710. Specifically, the ventilation fan 730 is provided so as to be close to or in contact with the control board 710.

  FIG. 5 is a partially enlarged view showing, in an enlarged manner, a state in which a ventilation fan 730 is provided so as to blow air toward the control board 710 above the control board 710 in the housing 900 shown in FIG. 3. 6 to 8 are diagrams showing a casing 900 that houses the control board 710. FIG. 6 is a front view showing an internal configuration of the casing 900, FIG. 7 is a front view of the casing 900, and FIG. 8 is a right side view of the casing 900. As shown in FIG. In FIG. 6, the illustration of the compensating conductors 811a and 812a in the casing 900 is omitted. 6 to 8 show a state in which various connection wirings including the thermocouple 810 are not connected to the housing 900.

  As shown in FIGS. 3 and 5 to 8, a control board 710 is provided on the upper side of one side in the longitudinal direction X (right side as viewed from the front in this example) in the housing 900.

  In the present embodiment, as shown in FIGS. 3 and 6, a terminal block 720 is provided in the lower part in the housing 900, and the other side in the longitudinal direction X (in this example, the left side when viewed from the front). Is provided with an inverter 910. As shown in FIG. 6, an electromagnetic contactor 920 to 920, a DC reactor 930, an electronic motor monitoring relay 940, a disconnection relay 950 to 950, a power relay 960 to 960, a DC / DC converter 970, etc. The electrical equipment is housed. The electromagnetic contactors 920 to 920, the DC reactor 930, the electronic motor monitoring relay 940, and the disconnection relay 950 to 950 are provided between the inverter 910 and the terminal block 720. The power relays 960 to 960 and the DC / DC converter 970 are provided between the control board 710 and the terminal block 720. At the lower part of the front surface 900a (front cover) (see FIGS. 7 and 8) of the housing 900, there are vent holes 901 (see FIGS. 7 and 8) (in this example, two vent holes 901 to 901 are in the longitudinal direction X). A vent 902 (see FIGS. 6 to 8) is provided at the upper portion of the right side surface 900b (right side cover) (see FIGS. 6 to 8) of the casing 900 (in this example, see FIG. 6 to FIG. 8). One vent 902 is provided on the back side in the depth direction Y. As a result, in the casing 900, air is circulated between the vent 902 in the right side surface 900b and the vent 901 in the front surface 900a. Further, as shown in FIG. 8, the control board 710 is stacked in a plurality of stages in the depth direction Y.

  The control board 710 is a casing so that the board surface 710a (see FIGS. 3 to 6 and 8) is vertical or substantially vertical (in this example, along both the vertical direction Z and the longitudinal direction X). 900. Specifically, the ventilation fan 730 blows air from the upper side (upper end surface) of the control board 710 toward the thermistor 820 in the control board 710 above the control board 710. The ventilation fan 730 is provided in the casing 900 so that the blowing direction W2 (see FIGS. 3 to 8) faces the thermistor 820 (that is, the thermistor 820 is included in the blowing area). The ventilation fan 730 is electrically connected to the output system of the control board 710, and at least when the thermocouple 810 measures the temperature measuring junction temperature Tm at the measurement location MS by an instruction signal from the control device 700. It is designed to be rotationally driven.

  In the present embodiment, the control board 710 is divided (specifically, divided into two). The two divided control boards 711, 712 (710) (see FIGS. 3 to 8) are arranged in the vertical direction Z so that the board surfaces 710a, 710a (see FIGS. 3 to 6 and 8) are aligned or substantially aligned with each other. Along the line. The reference contact RP of the thermocouple 810 is electrically connected to the lower control board 712 among the two divided control boards 711 and 712. The thermistor 820 (see FIGS. 3 to 6) is provided in the vicinity (close position) of the reference contact RP (see FIGS. 3 to 5) on the lower control board 712. A ventilation fan 730 (see FIGS. 3 and 5 to 8) is provided above the upper control board 711 so as to blow air toward the upper control board 711 and the lower control board 712. Specifically, the ventilation fan 730 is provided so as to be close to or in contact with the upper control board 711. Specifically, the ventilation fan 730 is directed above the upper control board 711 from the upper side (upper end surface) of the upper control board 711 to the thermistor 820 in the lower control board 712 via the upper control board 711. And blow.

(About this embodiment)
In this embodiment, the ventilation fan 730 is provided above the control board 710. Then, the air around the thermistor 820 provided on the control board 710 can be agitated by the ventilation fan 730 provided and driven so as to blow air toward the control board 710 above the control board 710, and thus The ambient temperature of the control board 710 (that is, the reference contact temperature Tr at the installation position where the reference contact RP of the thermocouple 810 provided on the control board 710 is installed and the detection position detected by the thermistor 820 provided on the control board 710) The reference contact temperature Tr1) can be made uniform. Thereby, it is possible to suppress the occurrence of temperature unevenness (for example, a local hot spot) between the installation position where the reference contact RP of the thermocouple 810 is installed and the detection position detected by the thermistor 820. The temperature difference between the reference contact temperature Tr at the installation position of the reference contact RP and the reference contact temperature Tr1 at the detection position of the thermistor 820 can be reduced.

  In the present embodiment, the control board 710 is divided and provided so that the board surfaces 710a and 710a are aligned or substantially aligned with each other, and among the divided control boards 711 and 712 (710), the thermocouple 810 is provided. The thermistor 820 is provided on the lower control board 712 to which the reference contact RP is electrically connected, and air is blown above the upper control board 711 toward the upper control board 711 and the lower control board 712. By providing and driving the ventilation fan 730, the ventilation fan 730 is provided and driven so as to blow air toward the upper control board 711 and the lower control board 712 above the upper control board 711. The air around the thermistor 820 provided on the lower control board 712 can be agitated. As a result, the ambient temperature of the lower control board 712 That is, the reference contact temperature Tr at the installation position where the reference contact RP of the thermocouple 810 provided on the lower control board 712 is installed and the reference at the detection position detected by the thermistor 820 provided on the lower control board 712. The contact temperature Tr1) can be made uniform. Thereby, it is possible to suppress the occurrence of temperature unevenness (for example, a local hot spot) between the installation position where the reference contact RP of the thermocouple 810 is installed and the detection position detected by the thermistor 820. The temperature difference between the reference contact temperature Tr1 at the installation position of the reference contact RP and the reference contact temperature Tr1 at the detection position of the thermistor 820 can be reduced. In this case, since the ventilation fan 730 blows the lower control board 712 with the upper control board 711 in between, the air volume of the ventilation fan 730 increases as the lower control board 712 is farther from the ventilation fan 730. And / or, the larger the installation space of the control board 710 in the housing 900, the larger.

  As described above, according to the present embodiment, the measurement error of the temperature measuring junction temperature Tm at the measurement point MS is reduced without grasping in advance the resistance value change accompanying the temperature change of the thermistor 820 and thus having a simple configuration. It becomes possible to suppress.

(Other embodiments)
In this embodiment, the control board 710 is divided into upper and lower parts, the reference contact RP of the thermocouple 810 is electrically connected to the lower control board 712, and the thermistor 820 is provided on the lower control board 712. However, instead of or in addition thereto, the reference contact RP of the thermocouple 810 may be electrically connected to the upper control board 711, and the thermistor 820 may be provided on the upper control board 711. Even in this case, the ventilation fan 730 is provided and driven above the upper control board 711 so as to blow air toward the upper control board 711 and the lower control board 712, so that the reference contact RP is on the upper side. A measurement error of the temperature measuring junction temperature Tm at the temperature measuring junction MP of the thermocouple 810 electrically connected to the control board 711 can be effectively suppressed. In the present embodiment, the control board 710 is divided into an upper control board 711 and a lower control board 712, but the control boards 711 and 712 are integrated (one). Also good.

  Moreover, in this Embodiment, although the temperature measuring device 800 was applied to the gas engine 300, it is not limited to it, It can apply to all other articles | goods.

  The present invention is not limited to the embodiment described above, and can be implemented in various other forms. Therefore, such an embodiment is merely an example in all respects and should not be interpreted in a limited manner. The scope of the present invention is shown by the scope of claims, and is not restricted by the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

DESCRIPTION OF SYMBOLS 100 Engine generator 300 Gas engine 301 Engine main body 602 Auxiliary board 603 Auxiliary board 700 Control apparatus 710 Control board 710a Board surface 711 Upper control board 712 Lower control board 720 Terminal block 730 Ventilation fan 800 Temperature measurement apparatus 810 Thermoelectric Pair 811 Metal conductor 812 Metal conductor 811a Compensation lead 812a Compensation lead 820 Thermistor 900 Case 900a Front 900b Right side 901 Vent 902 Vent 910 Inverter 920 Electromagnetic contactor 930 DC reactor 940 Electronic motor monitoring relay 950 Disconnect relay 960 Power relay 970 DC / DC converter CN Connector to CN1 Female connector CN2 Male connector JN Joint MC1 Metal conductor MC2 Metal conductor MP Temperature measurement contact MS Measurement location OP Opening portion RP Reference junction TC Thermoelectric TH thermistor TMD temperature measuring device Td temperature difference Tm temperature measuring contact temperature Tr reference contact temperature Tr1 reference contact temperature Vd thermoelectromotive force Vm temperature measuring contact voltage Vr reference contact voltage W1 cooling water flow direction W2 air flow direction X longitudinal direction Y depth direction Z Vertical direction

Claims (1)

A temperature measuring device that detects the temperature of a reference junction of a thermocouple provided with a temperature measuring contact at a measurement location by a thermistor for the reference contact,
A control board to which the reference contact of the thermocouple is electrically connected is housed in a housing, and the thermistor is provided on the control board,
A ventilation fan is provided and driven to blow air toward the control board above the control board ,
The lower control board to which the reference contact of the thermocouple is electrically connected among the divided control boards provided by dividing the control board so that the board surfaces are aligned or substantially aligned with each other. the thermistor is provided, the temperature measuring device which is characterized that you drive the ventilating fan arranged to blow toward the control board of the control board and the lower of the upper above the upper side of the control board.

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