JP5780299B2 - Cooling water temperature control device for internal combustion engine - Google Patents

Cooling water temperature control device for internal combustion engine Download PDF

Info

Publication number
JP5780299B2
JP5780299B2 JP2013511855A JP2013511855A JP5780299B2 JP 5780299 B2 JP5780299 B2 JP 5780299B2 JP 2013511855 A JP2013511855 A JP 2013511855A JP 2013511855 A JP2013511855 A JP 2013511855A JP 5780299 B2 JP5780299 B2 JP 5780299B2
Authority
JP
Japan
Prior art keywords
cooling water
heat
internal combustion
combustion engine
temperature
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP2013511855A
Other languages
Japanese (ja)
Other versions
JPWO2012147202A1 (en
Inventor
小山　崇
崇 小山
中谷　好一郎
好一郎 中谷
晃 山下
晃 山下
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Motor Corp
Original Assignee
Toyota Motor Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toyota Motor Corp filed Critical Toyota Motor Corp
Publication of JPWO2012147202A1 publication Critical patent/JPWO2012147202A1/en
Application granted granted Critical
Publication of JP5780299B2 publication Critical patent/JP5780299B2/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P7/00—Controlling of coolant flow
    • F01P7/14—Controlling of coolant flow the coolant being liquid
    • F01P7/16—Controlling of coolant flow the coolant being liquid by thermostatic control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P7/00—Controlling of coolant flow
    • F01P7/14—Controlling of coolant flow the coolant being liquid
    • F01P7/16—Controlling of coolant flow the coolant being liquid by thermostatic control
    • F01P7/167—Controlling of coolant flow the coolant being liquid by thermostatic control by adjusting the pre-set temperature according to engine parameters, e.g. engine load, engine speed
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P3/00—Liquid cooling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P3/00—Liquid cooling
    • F01P2003/001—Cooling liquid
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
    • F01P2037/00—Controlling

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Combined Controls Of Internal Combustion Engines (AREA)

Description

本発明は、内燃機関の冷却水温制御装置に関する。   The present invention relates to a cooling water temperature control device for an internal combustion engine.

電子的に弁開度を調整可能な弁開度調整手段を用いて内燃機関の冷却水の温度を制御するものであって、内燃機関の現在までの運転条件に基づいて冷却水の温度の最適値を推定し、将来の内燃機関の入口での冷却水の温度の推定値と、推定された最適値とに基づいて、弁開度調整手段の弁開度を調整する技術が知られている（例えば特許文献１参照）。この特許文献１の技術によると、より最適な温度に内燃機関の冷却水の温度を制御することができる。   The temperature of the cooling water of the internal combustion engine is controlled using a valve opening adjusting means that can adjust the valve opening electronically, and the optimum temperature of the cooling water is determined based on the operating conditions of the internal combustion engine up to the present time. A technique for estimating the valve opening of the valve opening adjusting means based on the estimated value of the coolant temperature at the inlet of the internal combustion engine in the future and the estimated optimum value is known. (For example, refer to Patent Document 1). According to the technique of Patent Document 1, the temperature of the cooling water of the internal combustion engine can be controlled to a more optimal temperature.

一方、内燃機関を冷却する冷却水として、固相状態と液相状態との一方から他方に相変化することにより媒体の比熱を変更する粒子を含むことで比熱が可変する冷却水を用いる技術が開示されている（例えば特許文献２参照）。   On the other hand, as cooling water for cooling an internal combustion engine, there is a technology that uses cooling water whose specific heat is variable by including particles that change the specific heat of the medium by changing the phase from one of a solid phase state and a liquid phase state to the other. It is disclosed (see, for example, Patent Document 2).

特開２００７−１００６３８号公報JP 2007-1000063 A 特開２００９−０４４８９６号公報JP 2009-044896 A 特開２００５−３２５７９０号公報JP 2005-325790 A

特許文献２に開示された比熱が可変する冷却水を使用する場合に、特許文献１に開示された技術を適用して冷却水の温度を基準に制御しようとすると、冷却水の比熱が可変する温度帯（相変化温度帯）が狭いので制御が適切に行えない。すなわち、冷却水の目標温度を相変化温度帯に設定して冷却水の温度が相変化温度帯に存在しても、冷却水の有する熱
量が相変化温度帯の許容範囲内であっても高ければ、更に熱量が加わると直ぐに冷却水の比熱が低くなり一気に冷却水の温度が上昇してオーバーヒートに陥ってしまうおそれがある。またこれを回避するために、冷却水の目標温度を相変化温度帯よりも低めに設定すると、内燃機関のオイルが冷えてしまい、内燃機関のフリクションが増加してしまうおそれがある。
When the cooling water disclosed in Patent Document 2 with variable specific heat is used, if the technique disclosed in Patent Document 1 is applied to control the cooling water based on the temperature, the specific heat of the cooling water varies. Since the temperature zone (phase change temperature zone) is narrow, control cannot be performed properly. That is, even by setting the target temperature of the cooling water in the phase change temperature range exists in the temperature phase change temperature range of the cooling water, heat of the cooling water
If the amount is high even if it is within the allowable range of the phase change temperature zone, when the amount of heat is further applied, the specific heat of the cooling water immediately decreases, and the temperature of the cooling water rises at a stretch and may overheat. In order to avoid this, if the target temperature of the cooling water is set lower than the phase change temperature range, the oil of the internal combustion engine may be cooled, and the friction of the internal combustion engine may increase.

本発明は、上記事情に鑑みてなされたものであって、比熱が可変する冷却水を使用する場合に、冷却水の温度を変更するための制御弁を適切に制御して冷却水の相変化温度帯を可及的に有効利用する技術を提供することを目的とする。   The present invention has been made in view of the above circumstances, and when using cooling water with variable specific heat, appropriately controlling a control valve for changing the temperature of the cooling water to change the phase of the cooling water The object is to provide a technology that makes effective use of temperature zones as much as possible.

本発明にあっては、以下の構成を採用する。すなわち、本発明は、
比熱が可変する冷却水を循環させる内燃機関の冷却水温制御装置であって、
前記冷却水が受ける熱量を算出する熱量算出手段と、
前記冷却水の流通経路又は流通量を変更して前記冷却水の温度を変更するために、指令に応じて開閉制御される制御弁と、
前記熱量算出手段によって算出される熱量に基づいて、前記制御弁を制御する制御手段と、
を備えた内燃機関の冷却水温制御装置である。
In the present invention, the following configuration is adopted. That is, the present invention
A cooling water temperature control device for an internal combustion engine that circulates cooling water with variable specific heat,
A calorie calculating means for calculating the amount of heat received by the cooling water;
A control valve that is controlled to open and close according to a command in order to change the temperature of the cooling water by changing the flow path or flow rate of the cooling water;
Control means for controlling the control valve based on the heat quantity calculated by the heat quantity calculation means;
Is a cooling water temperature control device for an internal combustion engine.

比熱が可変する冷却水は、冷却水の相変化温度帯では冷却水が受ける熱量がある程度変化しても冷却水の温度が変化しない。冷却水の相変化温度帯とは、冷却水中の粒子が相変化する等して冷却水の比熱が変化している状態の温度帯であり、この相変化温度帯では、冷却水に付与される熱量（受熱量）に変化が生じても、粒子の相変化が生じて比熱が変化し冷却水の温度が変化し難くなるものである。つまり、冷却水の相変化温度帯では、冷却水が温度変化しないままでいる熱量の許容範囲が広い。このため、冷却水の温度を基準に制御弁を制御しようとすると、冷却水の相変化温度帯が狭いので制御弁の制御が過剰となり適切に行えない場合がある。これは、冷却水の相変化温度帯における目標温度では、冷却水の熱量が判断できず、目標温度の冷却水であっても、相変化温度帯内の熱量として高い場合や低い場合が生じ得るからである。よって、目標温度の冷却水であっても、熱量が変化すると、直ぐに相変化温度帯から外れるおそれがある。しかし、冷却水の熱量を基準に制御弁を制御すれば、冷却水の相変化温度帯内の熱量の範囲が広いので、目標熱量を定めれば相変化温度帯を含む範囲で制御弁の制御が細かく適切に行える。
In the cooling water with variable specific heat, the temperature of the cooling water does not change even if the amount of heat received by the cooling water changes to some extent in the phase change temperature zone of the cooling water. The phase change temperature zone of the cooling water is a temperature zone in which the specific heat of the cooling water is changed due to a phase change of particles in the cooling water, and is given to the cooling water in this phase change temperature zone. Even if the amount of heat (amount of heat received) changes, a phase change of the particles occurs, the specific heat changes, and the temperature of the cooling water hardly changes. That is, in the phase change temperature zone of the cooling water, the allowable range of the amount of heat with which the cooling water remains unchanged is wide. For this reason, if it is going to control a control valve on the basis of the temperature of a cooling water, since the phase change temperature zone of a cooling water is narrow, control of a control valve may become excessive and may not be performed appropriately. This is because the heat quantity of the cooling water cannot be determined at the target temperature in the phase change temperature zone of the cooling water, and even if the cooling water has the target temperature, the heat quantity in the phase change temperature zone may be high or low. Because. Therefore, even if it is the cooling water of target temperature, if heat amount changes, there exists a possibility that it may remove | deviate from a phase change temperature range immediately. However, if the control valve is controlled based on the heat quantity of the cooling water, the range of heat quantity within the phase change temperature zone of the cooling water is wide, so if the target heat quantity is determined, the control valve can be controlled within the range including the phase change temperature zone. Can be done finely and appropriately.

これによると、例えば、冷却水の目標熱量を相変化温度帯内の低側熱量に設定すれば、更に熱量が加わっても冷却水の温度は相変化温度帯内に維持され、直ぐに冷却水の比熱が低くなり一気に冷却水の温度が上昇してオーバーヒートに陥ってしまうことを回避するこ
とができる。また、冷却水の目標熱量を過度に低めに設定する必要もなく、冷却水の温度が低すぎることに起因して内燃機関のオイルが冷えてしまい、内燃機関のフリクションが増加してしまうことを回避することができる。
According to this, for example, if the target heat quantity of the cooling water is set to a low-side heat quantity within the phase change temperature zone, the temperature of the cooling water is maintained within the phase change temperature zone even if the heat quantity is further applied, and immediately the cooling water It can be avoided that the specific heat is lowered and the temperature of the cooling water rises at once and falls into overheating. Moreover, it is not necessary to set the target heat quantity of the cooling water too low, and the oil of the internal combustion engine is cooled due to the cooling water temperature being too low, and the friction of the internal combustion engine is increased. It can be avoided.

本発明によると、比熱が可変する冷却水を使用する場合に、冷却水の温度を変更するための制御弁を適切に制御して冷却水の相変化温度帯を可及的に有効利用することができる。   According to the present invention, when cooling water with variable specific heat is used, the control valve for changing the temperature of the cooling water is appropriately controlled to effectively use the phase change temperature zone of the cooling water as much as possible. Can do.

前記熱量算出手段は、前記冷却水が内燃機関に流入する入口において有する入口熱量を算出し、
前記制御手段は、前記熱量算出手段によって算出される前記入口熱量が、前記冷却水に含まれ前記冷却水内で相変化可能な粒子が相変化して前記冷却水の比熱が変化している状態の相変化温度帯の低側開始熱量に近付くように、前記制御弁を制御するとよい。
The calorific value calculating means calculates an inlet calorie that the cooling water has at an inlet that flows into the internal combustion engine,
State the control means, wherein said inlet heat calculated by the heat amount calculating means, the specific heat of the cooling water contained phase change particles capable in said cooling water is changed phase the cooling water is changed The control valve may be controlled so as to approach the low-side starting heat quantity of the phase change temperature zone.

これによると、冷却水の目標入口熱量を相変化温度帯内の低側開始熱量に近付けるように設定することができるので、更に内燃機関において冷却水に熱量が加わっても冷却水の温度は相変化温度帯内に維持され、直ぐに冷却水の比熱が低くなり一気に冷却水の温度が上昇してオーバーヒートに陥ってしまうことを回避することができる。
According to this, since the target heat quantity of the cooling water can be set so as to be close to the low side starting heat quantity in the phase change temperature zone, even if the heat quantity is further applied to the cooling water in the internal combustion engine, the temperature of the cooling water is the phase. It is maintained in the change temperature zone, and it can be avoided that the specific heat of the cooling water immediately decreases and the temperature of the cooling water rises at once and falls into overheating.

前記熱量算出手段は、前記冷却水が内燃機関から流出する出口において有する出口熱量を算出し、
前記制御手段は、前記熱量算出手段によって算出される前記出口熱量が、前記相変化温度帯内の熱量を超えた高い熱量となる場合には、前記出口熱量が、前記相変化温度帯内の熱量に含まれるように、前記制御弁を制御するとよい。
The calorific value calculating means calculates an outlet heat amount that the cooling water has at an outlet from the internal combustion engine,
Wherein, said outlet heat calculated by the heat calculating means, if a higher quantity of heat exceeds the heat of the phase change in the temperature zone, the outlet amount of heat, heat of the phase change in the temperature zone The control valve may be controlled so as to be included in

これによると、冷却水の目標出口熱量を相変化温度帯内の熱量に含ませるように設定することができるので、内燃機関から流出する冷却水の温度は相変化温度帯内に維持され、直ぐに冷却水の比熱が低くなり一気に冷却水の温度が上昇してオーバーヒートに陥ってしまうことを回避することができる。
According to this, since it is possible to set the target outlet heat quantity of the cooling water to be included in the heat quantity in the phase change temperature zone, the temperature of the cooling water flowing out from the internal combustion engine is maintained in the phase change temperature zone and immediately It can be avoided that the specific heat of the cooling water decreases and the temperature of the cooling water rises at once and falls into overheating.

前記熱量算出手段が熱量を算出できない場合には、前記冷却水の温度が低下するように、前記制御弁を制御するとよい。
When the heat quantity calculation means cannot calculate the heat quantity , the control valve may be controlled so that the temperature of the cooling water decreases.

これによると、熱量を算出できない場合には、冷却水の温度を低下させ、冷却水の温度が上昇してオーバーヒートに陥ってしまうことを回避することができる。
According to this, when the amount of heat cannot be calculated, the temperature of the cooling water can be lowered, and the temperature of the cooling water can be prevented from rising and falling into overheating.

本発明によれば、比熱が可変する冷却水を使用する場合に、冷却水の温度を変更するための制御弁を適切に制御して冷却水の相変化温度帯を可及的に有効利用することができる。   According to the present invention, when using cooling water with variable specific heat, the control valve for changing the temperature of the cooling water is appropriately controlled to effectively use the phase change temperature zone of the cooling water as much as possible. be able to.

本発明の実施例１に係る内燃機関の概略構成を示す図である。1 is a diagram illustrating a schematic configuration of an internal combustion engine according to Embodiment 1 of the present invention. 実施例１に係る冷却水のモデルを示す図である。It is a figure which shows the model of the cooling water which concerns on Example 1. FIG. 実施例１に係る冷却水の温度と比熱との関係を示す図である。It is a figure which shows the relationship between the temperature of the cooling water which concerns on Example 1, and specific heat. 実施例１に係る比熱が変化する冷却水における、冷却水の単位量あたりの２５℃基準での受熱量と、冷却水の温度と、の関係の特性曲線を示す図である。It is a figure which shows the characteristic curve of the relationship between the amount of heat received on the basis of 25 degreeC per unit quantity of cooling water in the cooling water which the specific heat which concerns on Example 1 changes, and the temperature of a cooling water. 実施例１に係る内燃機関及び各種機器での熱量のモデルを示す図である。It is a figure which shows the model of the calorie | heat amount in the internal combustion engine which concerns on Example 1, and various apparatuses. 実施例１に係るラジエータを流通する冷却水の流量やバイパス通路を流通する冷却水の流量を算出するマップを示す図である。It is a figure which shows the map which calculates the flow volume of the cooling water which distribute | circulates the radiator which concerns on Example 1, and the flow volume of the cooling water which distribute | circulates a bypass channel. 実施例１に係るヒータコアを流通する冷却水の流量、リザーバタンクを流通する冷却水の流量、オイルクーラを流通する冷却水の流量、スロットル弁及びＥＧＲ弁を流通する冷却水の流量、又はＥＧＲクーラを流通する冷却水の流量を算出するマップを示す図である。The flow rate of the cooling water flowing through the heater core according to the first embodiment, the flow rate of the cooling water flowing through the reservoir tank, the flow rate of the cooling water flowing through the oil cooler, the flow rate of the cooling water flowing through the throttle valve and the EGR valve, or the EGR cooler It is a figure which shows the map which calculates the flow volume of the cooling water which distribute | circulates. 実施例１に係るラジエータでの放熱量やリザーバタンクでの放熱量を算出するマップを示す図である。It is a figure which shows the map which calculates the thermal radiation amount in the radiator which concerns on Example 1, and the thermal radiation amount in a reservoir tank. 実施例１に係るヒータコアでの放熱量を算出するマップを示す図である。It is a figure which shows the map which calculates the heat dissipation in the heater core which concerns on Example 1. FIG. 実施例１に係るオイルクーラでの放熱量、スロットル弁及びＥＧＲ弁での放熱量、又はＥＧＲクーラでの放熱量を算出するマップを示す図である。It is a figure which shows the map which calculates the heat radiation amount in the oil cooler which concerns on Example 1, the heat radiation amount in a throttle valve and an EGR valve, or the heat radiation amount in an EGR cooler. 実施例１に係る入口熱量に基づく電子サーモスタットの制御を示す図である。It is a figure which shows control of the electronic thermostat based on the inlet_heat | heat amount which concerns on Example 1. FIG. 実施例１に係る入口熱量に基づく電子サーモスタットの制御での問題点を示す図である。It is a figure which shows the problem in control of the electronic thermostat based on the inlet_heat | heat amount which concerns on Example 1. FIG. 実施例１に係る出口熱量に基づく電子サーモスタットの制御を示す図である。It is a figure which shows control of the electronic thermostat based on the exit calorie | heat amount which concerns on Example 1. FIG. 実施例１に係る入口熱量や出口熱量を算出できない場合の電子サーモスタットの制御を示す図である。It is a figure which shows control of the electronic thermostat in case the inlet_heat | heat amount and outlet_heat amount which concern on Example 1 cannot be calculated. 実施例１に係る冷却水温制御ルーチンを示すフローチャートである。3 is a flowchart illustrating a cooling water temperature control routine according to the first embodiment.

以下に本発明の具体的な実施例を説明する。
＜実施例１＞
図１は、本発明の実施例１に係る内燃機関の冷却水温制御装置を適用する内燃機関の概略構成を示す図である。図１に示す内燃機関１では、シリンダブロック及びシリンダヘッドを冷却するために冷却水が冷却水通路２を循環する。冷却水通路２としては、冷却水がラジエータ３を流通する通路２ａ、冷却水がオイルクーラ４を流通する通路２ｂ、冷却水がスロットル弁５ａ及びＥＧＲ弁５ｂを流通する通路２ｃ、冷却水がリザーバタンク６を流通する通路２ｄ、冷却水がヒータコア７を流通する通路２ｅ、冷却水がＥＧＲクーラ８を流通する通路２ｆ、冷却水がそのまま流通するバイパス通路２ｇが設けられている。Specific examples of the present invention will be described below.
<Example 1>
FIG. 1 is a diagram illustrating a schematic configuration of an internal combustion engine to which a cooling water temperature control device for an internal combustion engine according to a first embodiment of the present invention is applied. In the internal combustion engine 1 shown in FIG. 1, cooling water circulates through the cooling water passage 2 in order to cool the cylinder block and the cylinder head. The cooling water passage 2 includes a passage 2a through which the cooling water flows through the radiator 3, a passage 2b through which the cooling water flows through the oil cooler 4, a passage 2c through which the cooling water flows through the throttle valve 5a and the EGR valve 5b, and the cooling water as a reservoir. A passage 2d through which the tank 6 flows, a passage 2e through which the cooling water flows through the heater core 7, a passage 2f through which the cooling water flows through the EGR cooler 8, and a bypass passage 2g through which the cooling water flows as it is are provided.

ラジエータ３は、冷却水と外気とで熱交換して冷却水を冷却する。オイルクーラ４は、水冷式オイルクーラであり、内燃機関１に供給されるオイルと冷却水とで熱交換してオイルを冷却する。スロットル弁５ａは、内燃機関１で吸気量を制御する弁であり、冷却水で冷却される。ＥＧＲ弁５ｂは、内燃機関１に還流される排気の一部であるＥＧＲガス量を制御する弁であり、冷却水で冷却される。リザーバタンク６は、冷却水を一時的に貯留する。ヒータコア７は、冷却水を暖める。ＥＧＲクーラ８は、水冷式ＥＧＲクーラであり、内燃機関１に還流されるＥＧＲガスと冷却水とで熱交換してＥＧＲガスを冷却する。   The radiator 3 cools the cooling water by exchanging heat between the cooling water and outside air. The oil cooler 4 is a water-cooled oil cooler, and cools the oil by exchanging heat between the oil supplied to the internal combustion engine 1 and the cooling water. The throttle valve 5a is a valve that controls the intake air amount in the internal combustion engine 1, and is cooled by cooling water. The EGR valve 5b is a valve that controls the amount of EGR gas that is part of the exhaust gas recirculated to the internal combustion engine 1, and is cooled by cooling water. The reservoir tank 6 temporarily stores cooling water. The heater core 7 warms the cooling water. The EGR cooler 8 is a water-cooled EGR cooler, and cools the EGR gas by exchanging heat between the EGR gas recirculated to the internal combustion engine 1 and the cooling water.

冷却水がラジエータ３を流通する通路２ａには、シリンダブロックから通じる冷却水がオイルクーラ４を流通する通路２ｂが合流する。また、冷却水がラジエータ３を流通する通路２ａからは、冷却水がスロットル弁５ａ及びＥＧＲ弁５ｂを流通する通路２ｃ、並びに、冷却水がリザーバタンク６を流通する通路２ｄが分岐する。シリンダブロックから通じた冷却水がＥＧＲクーラ８を流通する通路２ｆは、冷却水がヒータコア７を流通する通路２ｅに合流する。   The passage 2 a through which the cooling water flows through the radiator 3 joins the passage 2 b through which the cooling water from the cylinder block flows through the oil cooler 4. The passage 2a through which the cooling water flows through the radiator 3 branches into a passage 2c through which the cooling water flows through the throttle valve 5a and the EGR valve 5b, and a passage 2d through which the cooling water flows through the reservoir tank 6. The passage 2 f through which the cooling water communicated from the cylinder block flows through the EGR cooler 8 joins the passage 2 e through which the cooling water flows through the heater core 7.

冷却水がラジエータ３を流通する通路２ａ及びバイパス通路２ｇが合流する部位には、電子サーモスタット９が配置されている。電子サーモスタット９は、指令に応じて開閉制御される制御弁であり、開弁することで冷却水がラジエータ３を流通するように冷却水の流通経路及び流通量を変更して冷却水の温度を低下させることができる。このとき、バイパス通路２ｇは冷却水の流通量が絞られる。反対に、電子サーモスタット９を閉弁することで冷却水がラジエータ３を流通し難くするように冷却水の流通経路及び流通量を変更して冷却水の温度を低下し難くすることができる。このとき、バイパス通路２ｇは冷却水の流通量が増加する。電子サーモスタット９の下流では冷却水をウォータポンプ１０に送り込む。ウォータポンプ１０は、冷却水を汲み上げて内燃機関１のシリンダブロックへ供給する。また、内燃機関１の出口に冷却水通路２が接続された部位には、水温センサ１１が配置され、水温センサ１１で内燃機関１から流出した冷却水の温度を検出する。   An electronic thermostat 9 is disposed at a portion where the passage 2a through which the cooling water flows through the radiator 3 and the bypass passage 2g merge. The electronic thermostat 9 is a control valve that is controlled to open and close in response to a command. By opening the valve, the flow path and flow rate of the cooling water are changed so that the cooling water flows through the radiator 3, and the temperature of the cooling water is adjusted. Can be reduced. At this time, the circulation amount of the cooling water is reduced in the bypass passage 2g. On the contrary, by closing the electronic thermostat 9, it is possible to change the flow path and flow rate of the cooling water so that the cooling water does not easily flow through the radiator 3, thereby making it difficult to lower the temperature of the cooling water. At this time, the circulation amount of the cooling water increases in the bypass passage 2g. Cooling water is fed into the water pump 10 downstream of the electronic thermostat 9. The water pump 10 pumps up cooling water and supplies it to the cylinder block of the internal combustion engine 1. Further, a water temperature sensor 11 is disposed at a portion where the cooling water passage 2 is connected to the outlet of the internal combustion engine 1, and the temperature of the cooling water flowing out from the internal combustion engine 1 is detected by the water temperature sensor 11.

ここで、冷却水通路２を流通する冷却水は、比熱が可変する冷却水である。すなわち、冷却水は、固相状態と液相状態との一方から他方に相変化することにより媒体の比熱を変更する粒子を含み比熱が可変する冷却水である。なお、粒子としては、固相状態と液相状態との一方から他方に相変化するものだけでなく、液相状態と気相状態との一方から他方に相変化するもの等を用いることができる。冷却水は、図２に示すように温度が一定以上になると内部の物質が固体から液体に相変化するような物質をカプセルで包んだ粒子を、冷却水の溶媒の中に混入させたものである。図２は、本実施例に係る冷却水のモデルを示す図である。図３は、本実施例に係る冷却水の温度と比熱との関係を示す図である。図２に示すように冷却水中の複数の粒子が固相状態と液相状態との一方から他方に相変化することにより、図３に示す複数の粒子が相変化して冷却水の比熱が変化している可変比熱領域が生じる。この可変比熱領域は、冷却水に熱量が付与されても、粒子が相変化して冷却水の比熱が変化している状態の相変化温度帯となる（図４参照）。図４は、本実施例に係る比熱が変化する冷却水における、冷却水の単位量あたりの２５℃基準での受熱量と、冷却水の温度と、の関係の特性曲線を示す図である。図４に示す相変化温度帯とは、冷却水中の粒子が固相状態と液相状態との一方から他方に相変化して冷却水の比熱が変化している状態の温度帯であり、この相変化温度帯では、冷却水に付与される熱量に変化が生じても、粒子の相変化が生じて比熱が変化し冷却水の温度が変化し難くなるものである。このような冷却水を用いることにより、内燃機関１の暖機過程では従来よりも冷却水の比熱を下げておくことで内燃機関１の暖機性を向上して燃費向上でき、暖機後はある一定の温度域（相変化温度帯）で比熱が高くなることから、熱量の許容範囲が増大してオーバーヒート等を回避することができる。
Here, the cooling water flowing through the cooling water passage 2 is cooling water whose specific heat is variable. That is, the cooling water is a cooling water that includes particles that change the specific heat of the medium by changing the phase from one of the solid phase state and the liquid phase state to the other and has a variable specific heat. As the particles, not only particles that change phase from one of a solid phase state and a liquid phase state to the other but also particles that change phase from one of a liquid phase state and a gas phase state to the other can be used. . As shown in FIG. 2, the cooling water is a mixture of particles encapsulating a substance that changes its phase from a solid to a liquid when the temperature rises above a certain level. is there. FIG. 2 is a diagram illustrating a cooling water model according to the present embodiment. FIG. 3 is a diagram illustrating the relationship between the temperature of the cooling water and the specific heat according to the present embodiment. As shown in FIG. 2, the plurality of particles in the cooling water undergo a phase change from one of the solid phase state and the liquid phase state to the other, whereby the plurality of particles shown in FIG. The variable specific heat region is generated. This variable specific heat region is a phase change temperature zone in which the phase of the particles is changed and the specific heat of the cooling water is changing even if heat is given to the cooling water (see FIG. 4). FIG. 4 is a diagram illustrating a characteristic curve of the relationship between the amount of heat received on the basis of 25 ° C. per unit amount of cooling water and the temperature of the cooling water in the cooling water in which specific heat varies according to the present embodiment. The phase change temperature zone shown in FIG. 4 is a temperature zone in which the specific heat of the cooling water is changed by the phase change of the particles in the cooling water from one of the solid phase state and the liquid phase state to the other. In the phase change temperature zone, even if the amount of heat applied to the cooling water changes, the phase change of the particles occurs, the specific heat changes, and the temperature of the cooling water hardly changes. By using such cooling water, the warm-up process of the internal combustion engine 1 can be improved in the warm-up process of the internal combustion engine 1 by lowering the specific heat of the coolant than before, so that the warm-up property of the internal combustion engine 1 can be improved and the fuel consumption can be improved. Since the specific heat becomes high in a certain temperature range (phase change temperature range), the allowable range of heat quantity is increased, and overheating and the like can be avoided.

この内燃機関１には、ＥＣＵ（電子制御ユニット）１２が併設されている。ＥＣＵ１２には、水温センサ１１等の各種センサが電気配線を介して接続され、これら各種センサの出力信号がＥＣＵ１２に入力されるようになっている。一方、ＥＣＵ１２には、スロットル弁５ａ、ＥＧＲ弁５ｂ、ヒータコア７、及び電子サーモスタット９、ウォータポンプ１０等が電気配線を介して接続されており、ＥＣＵ１２によりこれらの機器が制御される。   The internal combustion engine 1 is provided with an ECU (electronic control unit) 12. Various sensors such as the water temperature sensor 11 are connected to the ECU 12 via electric wiring, and output signals of these various sensors are input to the ECU 12. On the other hand, a throttle valve 5a, an EGR valve 5b, a heater core 7, an electronic thermostat 9, a water pump 10, and the like are connected to the ECU 12 through electric wiring, and these devices are controlled by the ECU 12.

（冷却水温制御）
従来から、電子サーモスタットを、冷却水の温度に基づいて制御することが行われていた。例えば、冷却水の将来の最適温度を推定し、その最適温度となるように電子サーモスタットを制御して冷却水の温度を調節するものである。しかしながら、冷却水として、本実施例のような比熱が可変する冷却水を用いる場合には、その冷却水の利点が生かせないという問題があった。(Cooling water temperature control)
Conventionally, an electronic thermostat has been controlled based on the temperature of cooling water. For example, the future optimum temperature of the cooling water is estimated, and the temperature of the cooling water is adjusted by controlling the electronic thermostat so as to be the optimum temperature. However, when the cooling water having a variable specific heat as in this embodiment is used as the cooling water, there is a problem that the advantage of the cooling water cannot be utilized.

すなわち、比熱が可変する冷却水は、冷却水の相変化温度帯では冷却水が受ける熱量がある程度変化しても冷却水の温度が変化しない。つまり、冷却水の相変化温度帯では、冷却水が温度変化しないままでいる熱量の許容範囲が広い。このため、従来のように冷却水の温度に基づいて電子サーモスタットを制御しようとすると、冷却水の相変化温度帯が狭いので電子サーモスタットの制御が過剰となり適切に行えない場合がある。これは、冷却水の相変化温度帯における目標温度では、冷却水の熱量が判断できず、目標温度の冷却水であっても、相変化温度帯内の熱量として高い場合（図４点Ａ）や低い場合が生じ得るからである。図４に示す点Ａは、内燃機関出口の冷却水が相変化温度帯内の目標温度であり、冷却水の熱量が相変化温度帯内において高い場合の冷却水の状態である。よって、相変化温度帯内の目標温度の冷却水であっても、熱量が変化すると、直ぐに相変化温度帯から外れるおそれがある。例えば図４の点Ａの場合には、急激な高負荷時等に熱量が増加すると、冷却水の温度が相変化温度帯を超えてしまい直ぐに冷却水の比熱が低くなり一気に冷却水の温度が上昇してオーバーヒートに陥ってしまう。
That is, in the cooling water with variable specific heat, the temperature of the cooling water does not change even if the amount of heat received by the cooling water changes to some extent in the phase change temperature zone of the cooling water. That is, in the phase change temperature zone of the cooling water, the allowable range of the amount of heat with which the cooling water remains unchanged is wide. For this reason, if an attempt is made to control the electronic thermostat based on the temperature of the cooling water as in the prior art, the phase change temperature zone of the cooling water is narrow, and thus the electronic thermostat may be overcontrolled and cannot be appropriately performed. This is the target temperature at the phase change temperature range of the cooling water can not determine the amount of heat of the cooling water, even in the cooling water target temperature, it is higher as the amount of heat in the phase change temperature zone (4 points A) This is because a low case may occur. Point A shown in FIG. 4 is the state of the cooling water when the cooling water at the outlet of the internal combustion engine is the target temperature in the phase change temperature zone and the amount of heat of the cooling water is high in the phase change temperature zone. Therefore, even if it is the cooling water of the target temperature in a phase change temperature range, if heat amount changes, there exists a possibility that it may remove | deviate from a phase change temperature range immediately. For example, in the case of point A in FIG. 4, when the amount of heat increases during a sudden high load or the like, the temperature of the cooling water exceeds the phase change temperature zone, and the specific heat of the cooling water immediately decreases, and the temperature of the cooling water quickly increases. It rises and falls into overheating.

このようなオーバーヒートを回避するように、冷却水の目標温度を相変化温度帯よりも低く設定することも考えられる。図４に示す点Ｂは、内燃機関出口の冷却水が相変化温度帯より低い目標温度の場合の冷却水の状態である。しかし、図４の点Ｂの場合には、冷却水通路を循環して温度低下した内燃機関入口の冷却水の温度が相変化温度帯よりも過度に低温になり、内燃機関のオイルが冷えてしまい、内燃機関のフリクションが増加してしまう。   In order to avoid such overheating, the target temperature of the cooling water may be set lower than the phase change temperature range. Point B shown in FIG. 4 is the state of the cooling water when the cooling water at the outlet of the internal combustion engine is at a target temperature lower than the phase change temperature zone. However, in the case of point B in FIG. 4, the temperature of the cooling water at the inlet of the internal combustion engine that has fallen in temperature due to circulation through the cooling water passage becomes excessively lower than the phase change temperature zone, and the oil in the internal combustion engine cools. As a result, the friction of the internal combustion engine increases.

以上のように、比熱が可変する冷却水を使用する場合に、電子サーモスタットを冷却水の温度に基づいて制御すると、比熱が可変する冷却水の利点が生かせず電子サーモスタットを適切に制御することができなかった。このため、冷却水の相変化温度帯を有効利用することができないものとなってしまっていた。   As described above, when the cooling water with variable specific heat is used, if the electronic thermostat is controlled based on the temperature of the cooling water, the advantage of the cooling water with variable specific heat cannot be utilized and the electronic thermostat can be appropriately controlled. could not. For this reason, the phase change temperature zone of the cooling water cannot be effectively used.

そこで、本実施例では、冷却水が受ける熱量を算出し、算出される熱量に基づいて、電子サーモスタット９を制御するようにした。このようにすれば、冷却水の相変化温度帯内の熱量の範囲が広いので、目標熱量を定めれば相変化温度帯を含む範囲で制御弁の制御が細かく適切に行える。
Therefore, in this embodiment, the amount of heat received by the cooling water is calculated, and the electronic thermostat 9 is controlled based on the calculated amount of heat . In this way, since the range of the heat quantity in the phase change temperature zone of the cooling water is wide, if the target heat quantity is determined, the control valve can be finely and appropriately controlled within the range including the phase change temperature zone.

本実施例の具体的な制御としては、冷却水が内燃機関に流入する入口において有する入口熱量を算出する。そして、算出される入口熱量が、粒子が相変化して冷却水の比熱が変化している状態の相変化温度帯の低側開始熱量に近付くように、電子サーモスタット９を制御する。
Specific control of this embodiment, cooling water is calculated inlet heat with the inlet flow into the internal combustion engine. Then, the electronic thermostat 9 is controlled so that the calculated inlet heat amount approaches the low-side starting heat amount in the phase change temperature zone in a state where the phase of the particles changes and the specific heat of the cooling water changes.

図５は、本実施例に係る内燃機関及び各種機器での熱量のモデルを示す図である。図５に示すように、内燃機関１の入口熱量は、内燃機関１から流出する出口における出口熱量と各種機器の授受熱量及び各種機器での流量とから算出することができる。入口熱量を算出するＥＣＵ１２が、本発明の熱量算出手段に対応する。各種機器の授受熱量は、ラジエータ３、バイパス通路２ｇ、ヒータコア７、リザーバタンク６、オイルクーラ４、スロットル弁５ａ及びＥＧＲ弁５ｂ、ＥＧＲクーラ８を夫々流通する冷却水の授受熱量である。各種機器での流量は、ラジエータ３、バイパス通路２ｇ、ヒータコア７、リザーバタンク６、オイルクーラ４、スロットル弁５ａ及びＥＧＲ弁５ｂ、ＥＧＲクーラ８を夫々流通する冷却水の流量である。
FIG. 5 is a diagram showing a model of heat quantity in the internal combustion engine and various devices according to the present embodiment. As shown in FIG. 5, the inlet heat of the internal combustion engine 1 can be calculated from the flow rate at exchange heat and various equipment outlet heat and various devices at the outlet that flows out of the internal combustion engine 1. The ECU 12 that calculates the inlet heat quantity corresponds to the heat quantity calculating means of the present invention. The amount of heat transferred between the various devices is the amount of heat transferred between the radiator 3, the bypass passage 2 g, the heater core 7, the reservoir tank 6, the oil cooler 4, the throttle valve 5 a and the EGR valve 5 b, and the EGR cooler 8. The flow rates in the various devices are the flow rates of cooling water flowing through the radiator 3, the bypass passage 2g, the heater core 7, the reservoir tank 6, the oil cooler 4, the throttle valve 5a, the EGR valve 5b, and the EGR cooler 8, respectively.

以下に内燃機関１の入口熱量の算出方法を説明する。まず、内燃機関１から流出する出口における出口熱量を算出する。出口熱量Ｑｅｎｇｏｕｔは、図４に示すように、水温センサ１１で検出した内燃機関１の出口での冷却水の温度Ｔｅｎｇｏｕｔを冷却水の特性曲線に取り込むことで導出することができる。出口熱量を算出するＥＣＵ１２が、本発明の熱量算出手段に対応する。
Hereinafter, a method for calculating the amount of heat input to the internal combustion engine 1 will be described. First, the outlet heat quantity at the outlet flowing out from the internal combustion engine 1 is calculated. As shown in FIG. 4, the outlet heat quantity Qengout can be derived by incorporating the temperature Tengout of the cooling water at the outlet of the internal combustion engine 1 detected by the water temperature sensor 11 into the characteristic curve of the cooling water. The ECU 12 that calculates the outlet heat quantity corresponds to the heat quantity calculating means of the present invention.

次に、各種機器での流量を算出する。図６は、本実施例に係るラジエータ３を流通する冷却水の流量Ｇｒａｄやバイパス通路２ｇを流通する冷却水の流量Ｇｂｙを算出するマップを示す図である。ＧｒａｄやＧｂｙは、電子サーモスタット９の弁開度とウォータポンプ１０の回転数とに依存するので、これらの値を図６に示すマップに取り込むことにより算出することができる。ここで、電子サーモスタット９の弁開度としては、制御上の開度を流用することができる。ウォータポンプ１０の回転数としては、機械式ウォータポンプの場合には、エンジン回転数に比例した値を用いることができ、電動式ウォータポンプの場合には、駆動モータの回転数を用いることができる。図７は、本実施例に係るヒータコア７を流通する冷却水の流量Ｇｈｅａｔ、リザーバタンク６を流通する冷却水の流量Ｇｒｅｓ、オイルクーラ４を流通する冷却水の流量Ｇｏｉｌ、スロットル弁５ａ及びＥＧＲ弁５ｂを流通する冷却水の流量Ｇｔｈｒ、又はＥＧＲクーラ８を流通する冷却水の流量Ｇｅｇｒを算出するマップを示す図である。Ｇｈｅａｔ、Ｇｒｅｓ、Ｇｏｉｌ、Ｇｔｈｒ、又はＧｅｇｒは、ウォータポンプ１０の回転数に依存するので、これらの値を図７に示すマップに取り込むことにより算出することができる。   Next, the flow rate in various devices is calculated. FIG. 6 is a diagram illustrating a map for calculating the flow rate Grad of the cooling water flowing through the radiator 3 and the flow rate Gby of the cooling water flowing through the bypass passage 2g according to the present embodiment. Since Grad and Gby depend on the valve opening of the electronic thermostat 9 and the rotational speed of the water pump 10, these values can be calculated by taking them into the map shown in FIG. Here, as the valve opening degree of the electronic thermostat 9, a control opening degree can be used. As the rotational speed of the water pump 10, a value proportional to the engine rotational speed can be used in the case of a mechanical water pump, and the rotational speed of a drive motor can be used in the case of an electric water pump. . 7 shows the flow rate Gheat of the cooling water flowing through the heater core 7 according to the present embodiment, the flow rate Gres of the cooling water flowing through the reservoir tank 6, the flow rate Goil of the cooling water flowing through the oil cooler 4, the throttle valve 5a and the EGR valve. It is a figure which shows the map which calculates the flow volume Gthr of the cooling water which distribute | circulates 5b, or the flow volume Gegr of the cooling water which distribute | circulates the EGR cooler 8. FIG. Since Gheat, Gres, Goil, Gthr, or Gegr depends on the number of rotations of the water pump 10, these values can be calculated by incorporating them into the map shown in FIG.

次に、各種機器の授受熱量を算出する。図８は、本実施例に係るラジエータ３での放熱量△Ｑｒａｄやリザーバタンク６での放熱量△Ｑｒｅｓを算出するマップを示す図である。△Ｑｒａｄや△Ｑｒｅｓは、各機器が受ける風速と各種機器を流通する冷却水の流量とに依存するので、これらの値を図８に示すマップに取り込むことにより算出することができる。ここで、風速としては、車速と車輌のファンの風速とを足した値等を用いることができる。図９は、本実施例に係るヒータコア７での放熱量△Ｑｈｅａｔを算出するマップを示す図である。△Ｑｈｅａｔは、ヒータ風量とヒータコア７を流通する冷却水の流量とに依存するので、これらの値を図９に示すマップに取り込むことにより算出することができる。図１０は、本実施例に係るオイルクーラ４での放熱量△Ｑｏｉｌ、スロットル弁５ａ及びＥＧＲ弁５ｂでの放熱量△Ｑｔｈｒ、又はＥＧＲクーラ８での放熱量△Ｑｅｇｒを算出するマップを示す図である。△Ｑｏｉｌ、△Ｑｔｈｒ、又は△Ｑｅｇｒは、水温センサ１１で検出した内燃機関１の出口での冷却水の温度と各種機器を流通する冷却水の流量とに依存するので、これらの値を図１０に示すマップに取り込むことにより算出することができる。そして、出口熱量から各種機器の放熱量を差し引いて各種機器を流通後の冷却水の熱量を算出する。すなわち、ラジエータ３流通後の熱量Ｑｒａｄ＝Ｑｅｎｇｏｕｔ−△Ｑｒａｄである。リザーバタンク６流通後の熱量Ｑｒｅｓ＝Ｑｅｎｇｏｕｔ−△Ｑｒｅｓである。なお、バイパス通路２ｇでは熱の授受がほとんど無いので、バイパス通路２ｇ流通後の熱量Ｑｂｙ＝Ｑｅｎｇｏｕｔである。ヒータコア７流通後の熱量Ｑｈｅａｔ＝Ｑｅｎｇｏｕｔ−△Ｑｈｅａｔである。オイルクーラ４流通後の熱量Ｑｏｉｌ＝Ｑｅｎｇｏｕｔ−△Ｑｏｉｌである。スロットル弁５ａ及びＥＧＲ弁５ｂ流通後の熱量Ｑｔｈｒ＝Ｑｅｎｇｏｕｔ−△Ｑｔｈｒである。ＥＧＲクーラ８流通後の熱量Ｑｅｇｒ＝Ｑｅｎｇｏｕｔ−△Ｑｅｇｒである。
Next, heat transfer amounts of various devices are calculated. FIG. 8 is a diagram illustrating a map for calculating the heat release amount ΔQrad in the radiator 3 and the heat release amount ΔQres in the reservoir tank 6 according to the present embodiment. Since ΔQrad and ΔQres depend on the wind speed received by each device and the flow rate of the cooling water flowing through the various devices, these values can be calculated by incorporating them into the map shown in FIG. Here, as the wind speed, a value obtained by adding the vehicle speed and the wind speed of the fan of the vehicle can be used. FIG. 9 is a diagram illustrating a map for calculating the heat release amount ΔQheat in the heater core 7 according to the present embodiment. Since ΔQheat depends on the heater air volume and the flow rate of the cooling water flowing through the heater core 7, it can be calculated by taking these values into the map shown in FIG. FIG. 10 is a diagram showing a map for calculating a heat release amount ΔQoil in the oil cooler 4 according to the present embodiment, a heat release amount ΔQthr in the throttle valve 5a and the EGR valve 5b, or a heat release amount ΔQegr in the EGR cooler 8. It is. ΔQoil, ΔQthr, or ΔQegr depends on the temperature of the cooling water at the outlet of the internal combustion engine 1 detected by the water temperature sensor 11 and the flow rate of the cooling water flowing through various devices. It can be calculated by taking in the map shown in FIG. Then, to calculate the heat of the cooling water after flowing through the various devices by subtracting the amount of heat radiated various devices from the outlet heat. That is, the amount of heat Qrad after the radiator 3 is distributed is Qrad = Qengout−ΔQrad. The amount of heat after circulation of the reservoir tank 6 is Qres = Qengout−ΔQres. Since there is almost no heat transfer in the bypass passage 2g, the heat quantity Qby = Qengout after the bypass passage 2g is distributed . The amount of heat after the heater core 7 is distributed is Qheat = Qengout−ΔQheat. The amount of heat Qoil after distribution of the oil cooler 4 = Qengout−ΔQoil. The amount of heat after the throttle valve 5a and the EGR valve 5b are distributed is Qthr = Qengout−ΔQthr. The amount of heat after distribution of the EGR cooler 8 is Qegr = Qengout−ΔQegr.

次に、内燃機関１に流入する入口における入口熱量を算出する。入口熱量Ｑｅｎｇｉｎは、各種機器流通後の熱量と各種機器での流量とを掛けたものの総和を各種機器での流量の和で割ったものである。すなわち、入口熱量Ｑｅｎｇｉｎ＝（Ｑｒａｄ×Ｇｒａｄ＋Ｑｒｅｓ×Ｇｒｅｓ＋Ｑｂｙ×Ｇｂｙ＋Ｑｈｅａｔ×Ｇｈｅａｔ＋Ｑｏｉｌ×Ｇｏｉｌ＋Ｑｔｈｒ×Ｇｔｈｒ＋Ｑｅｇｒ×Ｇｅｇｒ）÷（Ｇｒａｄ＋Ｇｒｅｓ＋Ｇｂｙ＋Ｇｈｅａｔ＋Ｇｏｉｌ＋Ｇｔｈｒ＋Ｇｅｇｒ）である。
Next, the amount of inlet heat at the inlet flowing into the internal combustion engine 1 is calculated. The inlet heat quantity Qengin is obtained by dividing the sum of the heat quantity after distribution of various devices and the flow rate of the various devices by the sum of the flow rates of the various devices. That is, the inlet heat Qengin = (Qrad × Grad + Qres × Gres + Qby × Gby + Qheat × Gheat + Qoil × Goil + Qthr × Gthr + Qegr × Gegr) ÷ (G rad + G res + G by + G heat + G oil + G thr + G egr).

図１１は、本実施例に係る入口熱量に基づく電子サーモスタット９の制御を示す図である。図１１に示すように、上記のようにして算出される入口熱量が、相変化温度帯の低側開始熱量に近付くように、電子サーモスタット９を制御する。言い換えると、算出される
入口熱量が、目標熱量である相変化温度帯の低側開始熱量となるように、電子サーモスタット９を制御する。相変化温度帯の低側開始熱量は、予め実験や検証等で定めておくことができる。電子サーモスタット９を制御するＥＣＵ１２が、本発明の制御手段に対応する。これにより、電子サーモスタット９は、入口熱量が相変化温度帯の低側開始熱量よりも低ければ、ラジエータ３に流入する冷却水の量を低減するように閉じ側に制御される。一方、電子サーモスタット９は、入口熱量が相変化温度帯の低側開始熱量よりも高ければ、ラジエータ３に流入する冷却水の量を増加するように開き側に制御される。
FIG. 11 is a diagram illustrating control of the electronic thermostat 9 based on the inlet heat amount according to the present embodiment. As shown in FIG. 11, the electronic thermostat 9 is controlled so that the inlet heat amount calculated as described above approaches the low-side starting heat amount in the phase change temperature zone. In other words, the electronic thermostat 9 is controlled so that the calculated inlet heat quantity becomes the low-side starting heat quantity in the phase change temperature zone that is the target heat quantity . The low-side starting heat quantity in the phase change temperature zone can be determined in advance through experiments, verifications, and the like. The ECU 12 that controls the electronic thermostat 9 corresponds to the control means of the present invention. Thus, the electronic thermostat 9 is controlled to the closed side so as to reduce the amount of cooling water flowing into the radiator 3 if the inlet heat quantity is lower than the low-side starting heat quantity in the phase change temperature zone. On the other hand, the electronic thermostat 9 is controlled to open so as to increase the amount of cooling water flowing into the radiator 3 if the inlet heat quantity is higher than the low-side starting heat quantity in the phase change temperature zone.

これによると、冷却水の目標熱量を相変化温度帯の低側開始熱量に設定することができるので、更に熱量が加わっても冷却水の温度は相変化温度帯内に維持され、直ぐに冷却水の比熱が低くなり一気に冷却水の温度が上昇してオーバーヒートに陥ってしまうことを回避することができる。また、冷却水の目標熱量を過度に低めに設定する必要もなく、冷却水の温度が低すぎることに起因して内燃機関のオイルが冷えてしまい、内燃機関のフリクションが増加してしまうことを回避することができる。
According to this, since the target heat quantity of the cooling water can be set to the low side starting heat quantity of the phase change temperature zone, the temperature of the cooling water is maintained within the phase change temperature zone even if the heat quantity is further added, and the cooling water is immediately It can be avoided that the specific heat of the water becomes low and the temperature of the cooling water rises at once and falls into overheating. Moreover, it is not necessary to set the target heat quantity of the cooling water too low, and the oil of the internal combustion engine is cooled due to the cooling water temperature being too low, and the friction of the internal combustion engine is increased. It can be avoided.

本実施例によると、比熱が可変する冷却水を使用する場合に、冷却水の温度を変更するための制御弁を適切に制御して冷却水の相変化温度帯を可及的に有効利用することができる。   According to this embodiment, when using cooling water with variable specific heat, the control valve for changing the temperature of the cooling water is appropriately controlled to effectively use the phase change temperature zone of the cooling water as much as possible. be able to.

図１２は、本実施例に係る入口熱量に基づく電子サーモスタット９の制御での問題点を示す図である。入口熱量に基づき電子サーモスタット９を制御していると、図１２に示すように、出口熱量が相変化温度帯を超えた高い熱量となる場合がある。この場合は、高負荷時等に生じる可能性があり、オーバーヒートし易い。
FIG. 12 is a diagram illustrating a problem in the control of the electronic thermostat 9 based on the inlet heat amount according to the present embodiment. When the electronic thermostat 9 is controlled based on the inlet heat quantity , as shown in FIG. 12, the outlet heat quantity may become a high heat quantity exceeding the phase change temperature zone. In this case, there is a possibility that it will occur at a high load, etc., and it is easy to overheat.

そこで、本実施例では、出口熱量が、相変化温度帯内の熱量を超えた高い熱量となる場合には、出口熱量が、相変化温度帯内のより高い熱量に近付くように、電子サーモスタット９を制御する。なお、出口熱量が、相変化温度帯内の熱量に含まれるように、電子サーモスタット９を制御するものでもよい。
Therefore, in this embodiment, when the outlet heat quantity becomes a high heat quantity exceeding the heat quantity in the phase change temperature zone, the electronic thermostat 9 is set so that the outlet heat quantity approaches a higher heat quantity in the phase change temperature zone. To control. Incidentally, the outlet amount of heat, so as to be included in the amount of heat in the phase change temperature range, may control the electronic thermostat 9.

本実施例の具体的な制御としては、入口熱量が、相変化温度帯の低側開始熱量に近付く
ように、電子サーモスタット９を制御していると、図１２に示すように、出口熱量が、相変化温度帯内の熱量を超えた高い熱量となる場合がある。その場合には、入口熱量に基づく制御を停止して、図１３に示すように、出口熱量が、相変化温度帯内のより高い熱量に近付くように、電子サーモスタット９を制御する。図１３は、本実施例に係る出口熱量に基づく電子サーモスタット９の制御を示す図である。ここで、出口熱量を相変化温度帯内のより高い熱量に近付けるのは、入口熱量もより高い熱量に維持することができるので、冷却水の相変化温度帯を有効利用することができるためである。
Specific control of this embodiment, the inlet amount of heat, so as to approach the low-side start heat of the phase change temperature range and controls the electronic thermostat 9, as shown in FIG. 12, the outlet amount of heat, in some cases a higher amount of heat exceeds the heat in the phase change temperature range. In that case, the control based on the inlet heat quantity is stopped, and the electronic thermostat 9 is controlled so that the outlet heat quantity approaches a higher heat quantity in the phase change temperature zone as shown in FIG. FIG. 13 is a diagram illustrating control of the electronic thermostat 9 based on the outlet heat quantity according to the present embodiment. Here, the reason why the outlet heat quantity is brought closer to the higher heat quantity within the phase change temperature zone is that the inlet heat quantity can be maintained at a higher heat quantity , so that the phase change temperature zone of the cooling water can be used effectively. is there.

これによると、冷却水の目標出口熱量を相変化温度帯内のより高い熱量に含ませるように設定することができるので、内燃機関から流出する冷却水の温度は相変化温度帯内に維持され、直ぐに冷却水の比熱が低くなり一気に冷却水の温度が上昇してオーバーヒートに陥ってしまうことを回避することができる。
According to this, the target outlet heat quantity of the cooling water can be set to be included in the higher heat quantity in the phase change temperature zone, so that the temperature of the cooling water flowing out from the internal combustion engine is maintained in the phase change temperature zone. It can be avoided that the specific heat of the cooling water immediately decreases and the temperature of the cooling water rises at once and falls into overheating.

上記のように、入口熱量や出口熱量に基づき電子サーモスタット９を制御していると、センサ異常、エンジン異常、各種機器の異常等の何らかの原因で入口熱量や出口熱量を算出することができなくなる場合がある。この場合には、入口熱量や出口熱量に基づき電子サーモスタット９を制御することができなくなる。
As described above, when controlling the electronic thermostat 9 based on the inlet heat and outlet heat, sensor failure, the engine abnormality, if for some reason such as abnormalities of the various devices it is not possible to calculate the inlet heat and outlet heat There is. In this case, the electronic thermostat 9 cannot be controlled based on the inlet heat amount or the outlet heat amount .

そこで、入口熱量や出口熱量を算出できない場合には、冷却水の温度が低下するように、電子サーモスタット９を制御する。
Therefore, when the heat quantity at the inlet and the heat quantity at the outlet cannot be calculated, the electronic thermostat 9 is controlled so that the temperature of the cooling water is lowered.

図１４は、本実施例に係る入口熱量や出口熱量を算出できない場合の電子サーモスタット９の制御を示す図である。本実施例の具体的な制御としては、ラジエータ３に冷却水が一定量以上流通させて出口熱量が相変化温度帯より低い熱量となるように、電子サーモスタット９を一定開度以上開き側に制御する。なお、異常事態であり、図１４に示す場合よりも出口熱量を低くしてもよいので、ラジエータ３に冷却水が流通可能な全量を流通させ
るように、電子サーモスタット９を全開に制御してもよい。
FIG. 14 is a diagram illustrating control of the electronic thermostat 9 when the inlet heat amount and the outlet heat amount according to the present embodiment cannot be calculated. As a specific control of the present embodiment, the electronic thermostat 9 is controlled to be opened more than a certain degree of opening so that the cooling water flows through the radiator 3 over a certain amount and the outlet heat amount becomes lower than the phase change temperature zone. To do. In addition, since it is an abnormal situation and the exit heat quantity may be lower than in the case shown in FIG. 14, even if the electronic thermostat 9 is controlled to be fully opened so that the radiator 3 can circulate all the amount of cooling water. Good.

これによると、熱量を算出できない場合には、冷却水の温度を低下させ、冷却水の温度が上昇してオーバーヒートに陥ってしまうことを回避することができる。
According to this, when the amount of heat cannot be calculated, the temperature of the cooling water can be lowered, and the temperature of the cooling water can be prevented from rising and falling into overheating.

（冷却水温制御ルーチン）
ＥＣＵ１２における冷却水温制御ルーチンについて、図１５に示すフローチャートに基づいて説明する。図１５は、本実施例に係る冷却水温制御ルーチンを示すフローチャートである。本ルーチンは、ＥＣＵ１２によって実行される。本ルーチンを実行するＥＣＵ１２が、本発明の制御手段に対応する。(Cooling water temperature control routine)
A cooling water temperature control routine in the ECU 12 will be described based on a flowchart shown in FIG. FIG. 15 is a flowchart showing a cooling water temperature control routine according to the present embodiment. This routine is executed by the ECU 12. The ECU 12 that executes this routine corresponds to the control means of the present invention.

図１５に示すルーチンが開始されると、Ｓ１０１では、入口熱量を算出する。この際、出口熱量も算出される。Ｓ１０２では、Ｓ１０１で入口熱量及び出口熱量の算出に誤り（ＮＧ）が生じたか否かを判別する。Ｓ１０２において肯定判定されると、Ｓ１０６へ移行する。Ｓ１０２において否定判定されると、Ｓ１０３へ移行する。Ｓ１０３では、出口熱量が相変化温度帯を超えた高い熱量となるか否かを判別する。Ｓ１０３において肯定判定された場合には、Ｓ１０５へ移行する。Ｓ１０３において否定判定された場合には、Ｓ１０４へ移行する。Ｓ１０４では、入口熱量が相変化温度帯の低側開始熱量に近付くように、電子サーモスタット９を制御する。Ｓ１０５では、出口熱量が相変化温度帯内のより高い熱量に近付くように、電子サーモスタット９を制御する。Ｓ１０６では、冷却水の温度が低下するように、電子サーモスタット９を制御する。Ｓ１０４〜Ｓ１０６の処理の後、本ルーチンを一旦終了する。
When the routine shown in FIG. 15 is started, an inlet heat quantity is calculated in S101. At this time, the outlet heat quantity is also calculated. In S102, it is determined whether or not an error (NG) has occurred in the calculation of the inlet heat amount and the outlet heat amount in S101. If a positive determination is made in S102, the process proceeds to S106. If a negative determination is made in S102, the process proceeds to S103. In S103, it is determined whether or not the outlet heat quantity is a high heat quantity exceeding the phase change temperature zone. If a positive determination is made in S103, the process proceeds to S105. If a negative determination is made in S103, the process proceeds to S104. In S104, the electronic thermostat 9 is controlled so that the inlet heat amount approaches the low-side starting heat amount in the phase change temperature zone. In S105, the electronic thermostat 9 is controlled so that the outlet heat amount approaches a higher heat amount in the phase change temperature zone. In S106, the electronic thermostat 9 is controlled so that the temperature of the cooling water decreases. This routine is once complete | finished after the process of S104-S106.

以上の本ルーチンであると、冷却水の温度を変更するための制御弁を適切に制御して冷却水の相変化温度帯を可及的に有効利用することができる。   In this routine, the control valve for changing the temperature of the cooling water can be appropriately controlled so that the phase change temperature zone of the cooling water can be used as effectively as possible.

＜その他＞
本発明に係る内燃機関の冷却水温制御装置は、上述の実施例に限定されるものではなく、本発明の要旨を逸脱しない範囲内において種々の変更を加えてもよい。<Others>
The cooling water temperature control apparatus for an internal combustion engine according to the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the gist of the present invention.

１ 内燃機関
２ 冷却水通路
３ ラジエータ
４ オイルクーラ
５ａ スロットル弁
５ｂ ＥＧＲ弁
６ リザーバタンク
７ ヒータコア
８ ＥＧＲクーラ
９ 電子サーモスタット
１０ ウォータポンプ
１１ 水温センサ
１２ ＥＣＵ1 Internal combustion engine 2 Cooling water passage 3 Radiator 4 Oil cooler 5a Throttle valve 5b EGR valve 6 Reservoir tank 7 Heater core 8 EGR cooler 9 Electronic thermostat 10 Water pump 11 Water temperature sensor 12 ECU

Claims (3)

比熱が可変する冷却水を循環させる内燃機関の冷却水温制御装置であって、
前記冷却水が内燃機関に流入する入口において有する入口熱量を算出する熱量算出手段と、
前記冷却水の流通経路又は流通量を変更して前記冷却水の温度を変更するために、指令に応じて開閉制御される制御弁と、
前記熱量算出手段によって算出される前記入口熱量が、前記冷却水に含まれ前記冷却水内で相変化可能な粒子が相変化して前記冷却水の比熱が変化している状態の相変化温度帯の低側開始熱量に近付くように、前記制御弁を制御する制御手段と、
を備えた内燃機関の冷却水温制御装置。 A cooling water temperature control device for an internal combustion engine that circulates cooling water with variable specific heat,
A calorific value calculating means for calculating an inlet calorific value of the cooling water at an inlet flowing into the internal combustion engine;
A control valve that is controlled to open and close according to a command in order to change the temperature of the cooling water by changing the flow path or flow rate of the cooling water;
Wherein the inlet heat is calculated by heat calculating means, the included in the cooling water the phase change temperature range in a state where the cooling varies the water in a phase changeable particles phase specific heat of the cooling water is changed Control means for controlling the control valve so as to approach the low-side starting heat quantity of
A cooling water temperature control device for an internal combustion engine comprising: 前記熱量算出手段は、前記冷却水が内燃機関から流出する出口において有する出口熱量を算出し、
前記制御手段は、前記熱量算出手段によって算出される前記出口熱量が、前記相変化温度帯内の熱量を超えた高い熱量となる場合には、前記出口熱量が、前記相変化温度帯内の熱量に含まれるように、前記制御弁を制御する請求項１に記載の内燃機関の冷却水温制御装置。 The calorific value calculating means calculates an outlet heat amount that the cooling water has at an outlet from the internal combustion engine,
Wherein, said outlet heat calculated by the heat calculating means, if a higher quantity of heat exceeds the heat of the phase change in the temperature zone, the outlet amount of heat, heat of the phase change in the temperature zone The cooling water temperature control device for an internal combustion engine according to claim 1, wherein the control valve is controlled to be included in the internal combustion engine. 前記熱量算出手段が熱量を算出できない場合には、前記冷却水の温度が低下するように、前記制御弁を制御する請求項１又は２に記載の内燃機関の冷却水温制御装置。 The cooling water temperature control device for an internal combustion engine according to claim 1 or 2, wherein when the heat amount calculation means cannot calculate a heat amount , the control valve is controlled so that the temperature of the cooling water is lowered.
JP2013511855A 2011-04-28 2011-04-28 Cooling water temperature control device for internal combustion engine Expired - Fee Related JP5780299B2 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2011/060443 WO2012147202A1 (en) 2011-04-28 2011-04-28 Coolant temperature control apparatus for internal combustion engine

Publications (2)

Publication Number Publication Date
JPWO2012147202A1 JPWO2012147202A1 (en) 2014-07-28
JP5780299B2 true JP5780299B2 (en) 2015-09-16

Family

ID=47071742

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2013511855A Expired - Fee Related JP5780299B2 (en) 2011-04-28 2011-04-28 Cooling water temperature control device for internal combustion engine

Country Status (5)

Country Link
US (1) US20140130753A1 (en)
EP (1) EP2703617A4 (en)
JP (1) JP5780299B2 (en)
CN (1) CN103502598A (en)
WO (1) WO2012147202A1 (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103711566B (en) * 2013-01-23 2016-03-30 日立汽车***(苏州）有限公司 Engine system
JP6347150B2 (en) * 2014-05-14 2018-06-27 スズキ株式会社 Motorcycle engine cooling system
KR101646130B1 (en) * 2015-03-02 2016-08-05 현대자동차 주식회사 Engine cooling system having thermostat
JP6557271B2 (en) * 2017-03-24 2019-08-07 トヨタ自動車株式会社 Cooling device for internal combustion engine
JP6658665B2 (en) * 2017-04-28 2020-03-04 トヨタ自動車株式会社 Internal combustion engine cooling system
KR102440603B1 (en) * 2017-10-24 2022-09-05 현대자동차 주식회사 Engine cooling system having egr cooler
CN110985194A (en) * 2019-12-23 2020-04-10 奇瑞汽车股份有限公司 Method and device for determining temperature of cooling water of engine

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006240501A (en) * 2005-03-03 2006-09-14 Nissan Motor Co Ltd Cooling system for hybrid vehicle
JP2007321633A (en) * 2006-05-31 2007-12-13 Nissan Motor Co Ltd Cooling device for vehicle and method of cooling heat source for vehicle
JP2009044896A (en) * 2007-08-10 2009-02-26 Nissan Motor Co Ltd Cooling system for vehicle
JP2009174362A (en) * 2008-01-23 2009-08-06 Toyota Motor Corp Exhaust gas recirculation gas cooling device of hybrid vehicle

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4768484A (en) * 1987-07-13 1988-09-06 General Motors Corporation Actively pressurized engine cooling system
US5381952A (en) * 1993-10-15 1995-01-17 Standard-Thomson Corporation Fail-safe thermostat
DE10117027C2 (en) * 2001-04-05 2003-03-27 Siemens Ag Liquid-cooled X-ray tube with phase change material (PCM) containing microcapsules in the cooling liquid
US20040019123A1 (en) * 2002-07-24 2004-01-29 Sehoon Kwak Multi-phase suspension coolant
JP4353851B2 (en) 2004-05-17 2009-10-28 三菱電機株式会社 Engine cooling system control method and engine cooling system control device
JP2006017436A (en) * 2004-07-05 2006-01-19 Honda Motor Co Ltd Thermal storage system
US7267086B2 (en) * 2005-02-23 2007-09-11 Emp Advanced Development, Llc Thermal management system and method for a heat producing system
GB2425619B (en) * 2005-03-22 2007-05-02 Visteon Global Tech Inc Method of engine cooling
JP4821247B2 (en) 2005-10-06 2011-11-24 トヨタ自動車株式会社 Cooling water control device for internal combustion engine
CN101566113B (en) * 2009-06-03 2011-06-08 浙江银轮机械股份有限公司 Engine waste heat recovery system based on organic rankine cycle

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006240501A (en) * 2005-03-03 2006-09-14 Nissan Motor Co Ltd Cooling system for hybrid vehicle
JP2007321633A (en) * 2006-05-31 2007-12-13 Nissan Motor Co Ltd Cooling device for vehicle and method of cooling heat source for vehicle
JP2009044896A (en) * 2007-08-10 2009-02-26 Nissan Motor Co Ltd Cooling system for vehicle
JP2009174362A (en) * 2008-01-23 2009-08-06 Toyota Motor Corp Exhaust gas recirculation gas cooling device of hybrid vehicle

Also Published As

Publication number Publication date
EP2703617A4 (en) 2015-06-24
US20140130753A1 (en) 2014-05-15
EP2703617A1 (en) 2014-03-05
CN103502598A (en) 2014-01-08
JPWO2012147202A1 (en) 2014-07-28
WO2012147202A1 (en) 2012-11-01

Similar Documents

Publication Publication Date Title
JP5780299B2 (en) Cooling water temperature control device for internal combustion engine
US9051870B2 (en) Coolant circuit for internal combustion engine with inlet-side flow control
WO2015125260A1 (en) Cooling system control device and cooling system control method
US9850802B2 (en) Coolant control device
JP2006348793A (en) Exhaust gas recirculation device for internal combustion engine
JP2015502497A (en) Apparatus and method for cooling coolant of vehicle cooling system
JP2011099400A (en) Cooling device for vehicle
JP6023430B2 (en) Water-cooled engine cooling system
JP4114640B2 (en) Thermoelectric generator
JP4975153B2 (en) Cooling device for internal combustion engine
US8978599B2 (en) Cooling apparatus of internal combustion engine for vehicle
JP5682634B2 (en) Internal combustion engine cooling system
CN108699946B (en) Cooling system for internal combustion engine
CN101813020B (en) Cooling means
JP6131937B2 (en) Cooling device for rotary piston engine
JP5637047B2 (en) Cooling water temperature control device for internal combustion engine
JP2005248903A (en) Cooling system control method of vehicle power source
WO2011089705A1 (en) Cooling device for vehicle
WO2012059969A1 (en) Cooling system for internal combustion engine
JP2016211482A (en) Engine cooling device
WO2016139631A1 (en) Engine fluid temperature regulating system and method
JP2006105105A (en) Engine cooling device
JP2010209818A (en) Cooling device for internal combustion engine
JP2017180165A (en) Engine device
JP5605319B2 (en) Cooling device for internal combustion engine

Legal Events

Date Code Title Description
A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20141007

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20141114

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20150616

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20150629

LAPS Cancellation because of no payment of annual fees