JP2009150266A - Cooling water controller of internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling water controller of an internal combustion engine promoting the warmup of the internal combustion engine, sufficiently recovering exhaust heat, and suppressing the boiling of cooling water. <P>SOLUTION: This cooling water controller comprises: a cooling water passage circulating between the internal combustion engine; an exhaust heat recovery device and a heater core; a bypassing passage; a flow distribution means; and a control means. The bypass passage is connected to the cooling water passage, and bypasses the internal combustion engine. The flow distribution means distributes the flow of the cooling water between a water jacket in the internal combustion engine and the bypass passage. The control means changes the ratio of the flow of the cooling water in the water jacket inside the internal combustion engine to the flow of the cooling water in the bypass passage. The warmup of the internal combustion engine is thereby promoted, the exhaust heat in the exhaust heat recovering device is sufficiently recovered, and the boiling of the cooling water is suppressed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cooling water control device for an internal combustion engine for promoting warm-up of the internal combustion engine.

  Conventionally, in order to cool or warm up an internal combustion engine (engine), a technique of circulating cooling water in the engine through a cooling water passage has been proposed. For example, Patent Document 1 describes a technology that accelerates engine warm-up by shortening the cooling water heating time by stopping the flow of cooling water in a water jacket in the engine at low temperature start. ing. Similarly, Patent Document 2 describes a technique for stopping the circulation of the cooling water in the water jacket for a predetermined period after the cold start.

JP 2004-301032 A JP 2006-214279 A

  However, in the techniques described in Patent Documents 1 and 2, when the cooling water passage is provided with the exhaust heat recovery device, when the cooling water circulation is stopped, the cooling water in the exhaust heat recovery device boils, Alternatively, when the heater core is provided in the cooling water passage, there is a possibility that the amount of heat that satisfies the heating requirement cannot be supplied to the heater core.

  The present invention has been made to solve the above-described problems, and can promote warm-up of an internal combustion engine (engine), sufficiently recover exhaust heat, and suppress boiling of cooling water. An object of the present invention is to provide a cooling water control device for an internal combustion engine.

  In one aspect of the present invention, a cooling water control device for an internal combustion engine having a cooling water passage that circulates between the internal combustion engine, an exhaust heat recovery device, and a heater core is connected to the cooling water passage and the internal combustion engine A bypass passage for bypassing, a flow distribution means for distributing the flow rate of cooling water between the water jacket in the internal combustion engine and the bypass passage, and a control means for controlling the flow distribution means, the control means Changes the ratio of the flow rate of the cooling water in the water jacket in the internal combustion engine and the flow rate of the cooling water in the bypass passage using the flow rate distribution means.

  The cooling water control apparatus for an internal combustion engine includes a cooling water passage that circulates between the internal combustion engine, the exhaust heat recovery device, and the heater core. The cooling water control device includes a bypass passage, a flow rate distribution unit, and a control unit. The bypass passage is connected to the cooling water passage and bypasses the internal combustion engine. The flow rate distribution means is, for example, a three-way valve, and distributes the flow rate of the cooling water between the water jacket in the internal combustion engine and the bypass passage. The control means is, for example, an ECU (Electronic Control Unit), and uses the flow rate distribution means to change the ratio between the flow rate of the cooling water in the water jacket in the internal combustion engine and the flow rate of the cooling water in the bypass passage. . For example, the ECU controls the flow rate distribution means to increase the flow rate of the cooling water in the bypass passage and to decrease the flow rate of the cooling water in the water jacket in the internal combustion engine when the internal combustion engine is warmed up. . In this way, when the internal combustion engine is warmed up, the warming up of the internal combustion engine can be promoted, and sufficient recovery of exhaust heat and suppression of boiling of cooling water in the exhaust heat recovery device are achieved. be able to.

  In another aspect of the cooling water control apparatus for an internal combustion engine, the control means is configured such that the required heat amount of the heater core is larger than the recovered heat amount recovered by the exhaust heat recovery device when the internal combustion engine is warmed up. If the temperature of the cooling water in the water jacket in the internal combustion engine is higher than the required temperature, the flow rate of the cooling water in the water jacket in the internal combustion engine is increased. Here, the required temperature is the amount of heat recovered in the internal combustion engine when the cooling water in the water jacket in the internal combustion engine flows through the heater core and becomes the recovered heat amount that can satisfy the required heat amount of the heater core. This is the temperature of the cooling water in the water jacket. By doing so, the warm-up of the internal combustion engine can be promoted, and the required heat amount of the heater core is satisfied when the required heat amount of the heater core is larger than the recovered heat amount by the exhaust heat recovery device. Can do.

  In a preferred embodiment of the cooling water control apparatus for an internal combustion engine, the required heat amount is a required heat amount according to at least one of a heating request, a defroster request, and a deice request.

  In another aspect of the cooling water control device for an internal combustion engine, the control means may be configured such that the temperature of the cooling water flowing through the exhaust heat recovery device is higher than the temperature of the cooling water in the water jacket in the internal combustion engine. If it is determined to be high, the flow rate of the cooling water in the water jacket in the internal combustion engine is increased. By doing in this way, useless heat dissipation by a radiator etc. can be controlled, for example, and warming up of an internal-combustion engine can be promoted.

  In another aspect of the cooling water control apparatus for an internal combustion engine, the flow distribution means is a three-way valve, and an intermediate temperature for mixing the cooling water in the water jacket and the cooling water in the bypass passage in the internal combustion engine. Has a mode. By doing in this way, the sudden change of the blowing temperature of the said heater core can be suppressed.

  In another aspect of the cooling water control apparatus for an internal combustion engine, the heater core is provided in a cooling water passage downstream of the exhaust heat recovery device. By doing in this way, the heat radiation of the cooling water in the cooling water passage can be minimized, and the heat radiation amount in the heater core can be increased.

  According to another aspect of the cooling water control apparatus for an internal combustion engine, the control means determines whether the required heat amount of the heater core is larger than the recovered heat amount recovered by the exhaust heat recovery device based on the intake air amount. Determine whether. Thereby, the required heat amount of the heater core can be satisfied, and the heating requirement and the like can be satisfied.

  According to another aspect of the cooling water control apparatus for an internal combustion engine, the control means may be configured such that when the integrated amount of the intake air amount in a predetermined time is larger than a predetermined amount, It is prohibited to increase the flow rate of the cooling water in the jacket. By doing in this way, the influence by temporary fluctuation | variation of the intake air amount can be excluded, and warming-up promotion of an internal combustion engine can be aimed at.

  Another aspect of the above cooling water control device for an internal combustion engine is a heater core inlet that estimates a water temperature in the vicinity of the inlet through which cooling water flows in the heater core, based on an integrated value of the intake air amount and an integrated value of the heater blower air volume. Water temperature estimation means is provided, and the control means controls the heater blower air volume of the heater core based on the coolant temperature estimated by the heater core inlet water temperature estimation means. Thereby, the deterioration of the heating performance of the heater core when the internal combustion engine is warmed up can be prevented.

  Another aspect of the cooling water control apparatus for an internal combustion engine described above includes a heater core inlet water temperature detection means for detecting a coolant temperature near the inlet flowing into the heater core, and the control means, after the warm-up is completed, When the water temperature detected by the heater core inlet water temperature detecting means is lower than a predetermined temperature, the flow rate of the cooling water in the bypass passage is increased, and the flow rate of the cooling water in the water jacket in the internal combustion engine is decreased. Here, the predetermined temperature is a temperature higher than the human body temperature, and is set to 50 ° C., for example. Thereby, it can suppress that the heating air which feels cold from the said heater core blows off.

  Another aspect of the cooling water control device for an internal combustion engine described above includes a bubble liquefaction means for liquefying bubbles generated in the cooling water in the internal combustion engine by heat exchange with cooling water passing through the bypass passage. Prepare. Here, the bubble liquefaction means is, for example, an air recovery unit connected to a water jacket in the internal combustion engine. Thereby, the raise of the pressure in a cooling water channel | path can be suppressed, and a cooling water leak can be prevented. Further, the cooling water passing through the bypass passage can be heated.

  Another aspect of the cooling water control apparatus for an internal combustion engine includes a bubble detection unit that detects bubbles generated in the cooling water in the internal combustion engine, and the control unit detects the bubble by the bubble detection unit. If this happens, the flow rate of the cooling water in the water jacket in the internal combustion engine is increased. Here, the bubble detection means is, for example, a temperature sensor attached to an air recovery space for recovering bubbles in an air recovery unit.

  In another aspect of the cooling water control apparatus for an internal combustion engine, the control means may determine a circulation direction of the cooling water after completion of warming up of the internal combustion engine, and a circulation direction of the cooling water when the internal combustion engine is warmed up. Reverse the direction. Thereby, boiling of the cooling water after completion of warming up of the internal combustion engine can be suppressed.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
First, the cooling water control apparatus according to the first embodiment of the present invention will be described. FIG. 1 is a diagram illustrating a schematic configuration of a cooling water control apparatus 100 according to the first embodiment.

  The cooling water control device 100 includes a cooling water passage connected to the engine 1, an exhaust heat recovery device 2, and a heater core 5. The cooling water control device 100 cools the engine 1 using the cooling water and collects exhaust heat by exchanging heat between the cooling water and the exhaust gas to warm up the engine 1 and the heater core 5. This device is used as a heat source. The cooling water passes through the cooling water passages 7a, 7b, 7c, 7d1, 7d2, 7e, and 7f, thereby cooling and warming up the engine 1. In FIG. 1, the solid arrow indicates the flow of the cooling water when the engine 1 is warmed up (Cold), and the broken line arrow indicates the flow of the cooling water after the engine 1 is warmed up (Hot). In addition, the arrow of a dashed-dotted line has shown the input / output of the signal.

  The cooling water passage 7 e extends from the engine 1 and is connected to the cooling water passages 7 d 2 and 7 f via the three-way valve 6. The cooling water passage 7 f is connected to the cooling water passage 7 a via the heater core 5. An exhaust heat recovery device 2 is provided on the cooling water passage 7 a, and the cooling water passes through the exhaust heat recovery device 2. The cooling water passage 7 a is connected to the cooling water passage 7 b, the cooling water passage 7 c extending from the engine 1, and the thermostat 4. The radiator 3 is provided on the cooling water passage 7c. An electric water pump (hereinafter referred to as “electric WP”) is provided on the cooling water passage 7b. The cooling water passage 7b is connected to the cooling water passages 7d1 and 7d2. The cooling water passage 7d1 communicates with a water jacket (not shown) in the engine 1. The cooling water passage 7 d 2 is a bypass passage that bypasses the engine 1, and is connected to the cooling water passages 7 e and 7 f via the three-way valve 6. In the following, the cooling water passage 7d2 may be referred to as a “detour passage 7d2” to indicate that it is a cooling water passage that bypasses the engine 1. Further, when the cooling water passages 7a, 7b, 7c, 7d1, 7d2, 7e, and 7f are not distinguished, they are simply referred to as the cooling water passage 7.

  The engine 1 is a device that generates power by burning a mixture of supplied fuel and air. For example, the engine 1 is configured by a gasoline engine, a diesel engine, or the like. The engine 1 is mounted on a hybrid vehicle or the like. The cooling water flows into the engine 1 from the cooling water passage 7d1. The cooling water flowing into the engine 1 passes through the water jacket in the engine 1 and then flows out from the cooling water passages 7c and 7e. The water jacket is provided around a cylinder (not shown) in the engine 1, and the cylinder exchanges heat with the cooling water passing through the water jacket.

  Near the exit of the engine 1 to the cooling water passage 7e, there is provided a water temperature sensor 9a for detecting the temperature of the cooling water in the engine 1, more precisely, the temperature of the cooling water in the water jacket in the engine 1. Yes. The water temperature sensor 9a detects the coolant temperature in the water jacket in the engine 1 and supplies a corresponding detection signal S9a to the ECU 20.

  The three-way valve 6 has a cooling water inlet / outlet in three directions, and has an openable / closable valve at the inlet / outlet in each direction. In the example shown in FIG. 1, the three-way valve 6 has a cooling water inlet / outlet in each direction of the cooling water passages 7d2, 7e, 7f, and a valve f1 at the inlet / outlet of each direction of the cooling water passages 7d2, 7e, 7f. , F2, and f3. The three-way valve 6 opens and closes the inlet / outlet valves in each direction based on a control signal S6 from the ECU 20. Specifically, when cold, the three-way valve 6 opens the valves f1 and f3 at the inlets and outlets in the respective directions of the cooling water passages 7d2 and 7f, and closes the valve f2 at the inlet and outlets in the direction of the cooling water passages 7e. Thus, the cooling water is circulated through a route that passes through the bypass passage 7d2 (a route indicated by a solid line arrow, which may be referred to as a cold cooling water route hereinafter). Further, the three-way valve 6 opens the valves f2 and f3 at the inlet / outlet in each direction of the cooling water passages 7e and 7f and closes the valve f1 at the inlet / outlet in the direction of the cooling water passage 7d2 during the hot state. Coolant is circulated through a route that passes through the inside of the engine 1, more precisely, a route that passes through the water jacket in the engine 1 (route indicated by a wavy arrow, hereinafter sometimes referred to as a hot water coolant route). That is, the three-way valve 6 distributes the flow rate of the cooling water between the water jacket in the engine 1 and the bypass passage 7d2. Therefore, the three-way valve 6 corresponds to the flow distribution means in the present invention. The position of the three-way valve 6 is not limited to the position shown in FIG. In short, the cooling water passage route (hereinafter simply referred to as “cooling water route”) may be changed between the route passing through the water jacket in the engine 1 and the route passing through the bypass passage 7d2. Any position can be used. Therefore, the three-way valve 6 may be attached at the position indicated by the point Ps instead of being provided at the position shown in FIG.

  The exhaust heat recovery device 2 is provided on an exhaust passage (not shown) through which exhaust gas from the engine 1 passes. The exhaust heat recovery device 2 recovers exhaust heat by allowing cooling water to pass through and exchanging heat between the cooling water and the exhaust gas. Thereby, the cooling water is heated.

  The electric WP 8 includes an electric motor, and the cooling water is circulated in the cooling water passage 7 by driving the motor. Specifically, the electric WP 8 is supplied with electric power from a battery, and the rotation speed and the like are controlled by a control signal supplied from the ECU 20. Instead of the electric WP 8, a mechanical water pump that can operate regardless of the operation of the engine 1 and can be controlled by the ECU 20 may be used.

  The heater core 5 is a device (heating device) that warms the air in the vehicle interior with cooling water passing through the inside. In this case, the air heated by the heater core 5 is blown into the vehicle interior by a blower called a heater blower (not shown).

  In the radiator 3, the cooling water passing through the inside thereof is cooled by outside air. In this case, cooling of the cooling water in the radiator 3 is promoted by the wind introduced by the rotation of the electric fan (not shown).

  The thermostat 4 is configured by a valve that opens and closes according to the temperature of the cooling water. Basically, the thermostat 4 opens when the temperature of the cooling water becomes high. In this case, the cooling water passage 7 b and the cooling water passage 7 c are connected via the thermostat 4, and the cooling water passes through the radiator 3. Thereby, a cooling water is cooled and the overheating of the engine 1 is suppressed. On the other hand, when the temperature of the cooling water is relatively low, the thermostat 4 is closed. In this case, the cooling water does not pass through the radiator 3. Thereby, since the temperature fall of a cooling water is suppressed, the overcool of the engine 1 is suppressed.

  The ECU (Electronic Control Unit) 20 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like (not shown). The ECU 20 controls the cooling water control device 100 based on detection signals supplied from various sensors (not shown). For example, in 1st Embodiment, ECU20 calculates | requires the water temperature of the cooling water in the water jacket in the engine 1 based on the detection signal 9a from the water temperature sensor 9a. The ECU 20 determines whether or not the warm-up has been completed based on the obtained water temperature, and controls the three-way valve 6. Therefore, the ECU 20 functions as a control unit in the present invention.

(Cooling water route switching control process)
Next, the cooling water route switching control process according to the first embodiment will be described. In the cooling water route switching control process according to the first embodiment, when the engine 1 is warmed up (Cold), the ECU 20 is a route that passes through the bypass passage 7d2, that is, a Cold cooling water route that bypasses the engine 1. After the engine 1 has been warmed up (at the time of hot), the coolant is circulated through a route passing through the engine 1, more precisely, a route passing through the water jacket in the engine 1. And

  Specifically, the ECU 20 determines whether or not the warm-up is completed depending on whether or not the water temperature detected by the water temperature sensor 9a is higher than a predetermined temperature. Therefore, the predetermined temperature is a reference temperature for determining whether or not the engine 1 has been warmed up. When the ECU 20 determines that the warm-up has not been completed, that is, during Cold, the ECU 20 controls the three-way valve 6 to cool the Cold cooling water route that bypasses the engine 1 as indicated by the solid arrow. The water is circulated and the cooling water is not circulated through the hot cooling water route passing through the water jacket in the engine 1. That is, the ECU 20 stops the flow of the cooling water in the water jacket in the engine 1. The reason for this is as follows.

  When the cooling water flows through the water jacket in the engine 1 during Cold, relatively low-temperature cooling water flows through the water jacket in the engine 1. In this case, the cooling water flowing through the water jacket in the engine 1 takes away the heat of combustion of the engine 1, so that warm-up of the engine 1 is hindered. Therefore, in the first embodiment, the warm-up of the engine 1 is promoted by not allowing the coolant to flow through the route passing through the engine 1.

  The reason why the cooling water is not circulated completely in the cooling water passage 7 during Cold but the cooling water is circulated in the Cold cooling water route that bypasses the engine 1 is that the cooling water passage 7 This is because when the circulation of the cooling water as a whole is completely stopped, the cooling water may be boiled in the exhaust heat recovery device 2 because the temperature of the cooling water is too high. Alternatively, by completely stopping the circulation of the cooling water, the exhaust heat cannot be sufficiently recovered, and the heating requirement of the heater core 5 may not be satisfied. Therefore, in the cooling water control apparatus 100 according to the first embodiment, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1 during Cold, so that the exhaust heat recovery device 2 and the heater core 5 Cooling water is circulated between them to sufficiently recover exhaust heat and suppress boiling of cooling water.

  On the other hand, when it is determined that the warm-up has been completed, that is, in the hot state, the ECU 20 switches the cooling water route by controlling the three-way valve 6. Specifically, the ECU 20 circulates the cooling water in the Hot cooling water route passing through the engine 1 and stops the cooling water circulation in the Cold cooling water route that bypasses the engine 1. Thereby, the cooling water heated by the engine 1 can be supplied to the heater core 5.

  Next, the cooling water route switching control process according to the first embodiment will be described using the flowchart shown in FIG.

  In step S101, the ECU 20 determines whether or not the water temperature THW1 in the engine 1 detected by the water temperature sensor 9a is higher than a predetermined temperature. The predetermined temperature is a reference temperature for determining whether or not the warm-up of the engine 1 is completed, and is about 90 ° C., for example. The predetermined temperature is obtained in advance by experiments or the like and stored in a ROM or the like. That is, this process is a process for determining whether or not the engine 1 has been warmed up.

  When the ECU 20 determines that the water temperature THW1 in the engine 1 is higher than the predetermined temperature (step S101: Yes), the ECU 20 determines that the engine 1 has been warmed up, and controls the three-way valve 6. The cooling water is circulated through the hot cooling water route passing through the engine 1 (step S102). On the other hand, when the ECU 20 determines that the water temperature THW1 in the engine 1 is equal to or lower than the predetermined temperature (step S101: No), the ECU 20 determines that the engine 1 is warming up and controls the three-way valve 6. Thus, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1 (step S103). Thereby, warm-up of the engine 1 can be promoted. ECU20 complete | finishes this control process, after the process of step S102 or step S103 performs.

  According to the first embodiment described above, warm-up of the engine 1 can be promoted during Cold, and sufficient exhaust heat recovery and suppression of boiling of cooling water can be achieved.

  In addition, in the cooling water control apparatus 100 according to the first embodiment, an engine, an exhaust heat recovery device, and a heater core are provided on one cooling water passage. By doing in this way, independently of the cooling water passage connecting the exhaust heat recovery device and the engine, separately from the cooling water control device configured to provide the cooling water passage connecting the exhaust heat recovery device and the heater core, Only one electric WP 8 is required, and the size of the cooling water control device itself can be reduced.

(Modification of the first embodiment)
Here, a modification of the first embodiment will be described. In the first embodiment described above, the cooling water is circulated in either the Hot cooling water route that passes through the engine 1 or the Cold cooling water route that bypasses the engine 1. The cooling water route is circulated through the hot-time cooling water route passing through the engine 1, and the cooling water is not circulated through the cold-time cooling water route that bypasses the engine 1. However, when the required cooling water flow rate of the exhaust heat recovery device 2 is larger than the required cooling water flow rate of the engine 1 during hot, the electric WP 8 increases the cooling water flow rate higher than the required flow rate of the engine 1. It is necessary to let Therefore, the ECU 20 needs to make the power of the electric WP 8 larger than the power that satisfies the required flow rate of the engine 1, and the power consumption of the electric WP 8 increases.

  Therefore, in the modification of the first embodiment, as the three-way valve 6, a flow distribution three-way valve capable of changing the distribution ratio of the flow rate of the cooling water between the water jacket in the engine 1 and the bypass passage 7d2 is used. And When the required flow rate of the exhaust heat recovery device 2 is larger than the required flow rate of the engine 1 at the time of Hot, the ECU 20 controls the three-way valve 6 (flow distribution three-way valve) to cool the Cold at the time of bypassing the engine 1. Cooling water will also be distributed through the water route. By doing in this way, even if the required flow rate of the exhaust heat recovery device 2 is larger than the required flow rate of the engine 1, it becomes possible to suppress the increase in the flow rate of the cooling water in the engine 1, and the electric WP8. Can be reduced. Moreover, the pressure loss of the cooling water control device 100 as a whole can be reduced by allowing the cooling water to flow through the Cold cooling water route that bypasses the engine 1 having a large pressure loss. Thereby, in the modification of 1st Embodiment, the power consumption of electric WP8 can be reduced.

  Further, in the first embodiment described above, at the time of Cold, by controlling the three-way valve 6, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1, and the Hot cooling that passes through the engine 1 is performed. It was said that cooling water would not be distributed through the water route. However, the present invention is not limited to this, and instead, as the three-way valve 6, a flow rate distribution three-way valve may be used to adjust the flow rate in the Cold cooling water route and the flow rate in the Hot cooling water route. That is, the ECU 20 may change the ratio of the flow rate of the cooling water in the bypass passage 7d2 and the flow rate of the cooling water in the engine 1 by using the three-way valve 6 (flow rate distribution three-way valve) during Cold. For example, the ECU 20 may increase the flow rate of the cooling water in the bypass passage 7d2 and decrease the flow rate of the cooling water in the engine 1 by using the three-way valve 6 that is a flow rate distribution three-way valve during Cold. As a result, during Cold, the flow rate of cooling water in the Cold cooling water route that bypasses the engine 1 increases, and the flow rate of cooling water in the Hot cooling water route that passes through the engine 1 decreases. Even in this case, warming up of the engine 1 can be promoted during Cold, and sufficient recovery of exhaust heat and suppression of boiling of cooling water can be achieved.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The configuration of the cooling water control apparatus according to the second embodiment is the same as the configuration of the cooling water control apparatus 100 according to the first embodiment.

  In the first embodiment described above, by controlling the three-way valve 6 during Cold, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1, and the Hot cooling that passes through the engine 1 is performed. It was said that cooling water would not be distributed through the water route. However, during Cold, for example, when there is at least one of a heating request, a defroster request, and a deice request, the required heat amount of the heater core 5 may be larger than the recovered heat amount by the exhaust heat recovery device 2. is there. Here, the defroster indicates an operation in which the heater core 5 removes frost by blowing warm air from the vehicle interior toward the windshield, etc., and deice means that the heater core 5 sends warm air from outside the vehicle cabin to the windshield or the like. This shows the action of removing ice and snow frozen on the windshield etc. When the required heat quantity of the heater core 5 is larger than the recovered heat quantity by the exhaust heat recovery device 2, the required heat quantity of the heater core 5 can be satisfied only by circulating the cooling water through the Cold cooling water route that bypasses the engine 1. There is a risk that it will not be possible.

  Therefore, in the second embodiment, when the ECU 20 determines that the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2 at Cold time, the ECU 20 switches the cooling water route and moves the inside of the engine 1. The cooling water is circulated through the passing hot water route. By doing so, even during Cold, when the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2, the relatively high-temperature cooling heated by the combustion heat of the engine 1 is performed. Water can be supplied to the heater core 5 and the required heat quantity of the heater core 5 can be satisfied.

(Cooling water route switching process)
The cooling water route switching process according to the second embodiment will be described with reference to the flowchart shown in FIG. In the cooling water route switching processing according to the second embodiment, it is determined whether or not the cooling water route switching processing according to the first embodiment described above, that is, warming up of the engine 1 is completed, and the cooling water route is determined. In addition to the switching process, a process for determining whether or not the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2 is performed. The details will be described below.

  In step S111, the ECU 20 determines whether the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2, and whether the water temperature THW1 in the engine 1 is higher than the required temperature. For example, when there is a heating request, the ECU 20 calculates the required heat amount of the heater core 9 based on the air conditioner set temperature, the outside air temperature, the inside air temperature, etc., and based on the fuel injection amount, the outside air temperature, the cooling water flow rate, and the like. Thus, the amount of heat recovered by the exhaust heat recovery device 2 is calculated. The required temperature is the temperature of the cooling water in the engine 1 when the cooling water in the engine 1 flows through the heater core 5 and becomes the recovered heat quantity that can satisfy the required heat quantity of the heater core 5. . The required temperature is obtained in advance by experiments and recorded in a ROM or the like.

  When the ECU 20 determines that the calculated required heat amount is larger than the calculated recovered heat amount and the water temperature THW1 in the engine 1 is higher than the required temperature (step S111: Yes), the process proceeds to step S113. If not, the process proceeds to step S112. In step S111, the ECU 20 considers that the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2 when there is any request among the defroster request and the deice request.

  In step S <b> 113, the ECU 20 controls the three-way valve 6 to distribute the cooling water through the hot cooling water route passing through the engine 1. By doing in this way, even if it is Cold, when the required heat quantity of the heater core 5 becomes larger than the recovered heat quantity by the exhaust heat recovery device 2, the cooling water can be circulated through the hot cooling water route. The required heat quantity of the heater core 5 can be satisfied.

  In step S112, the ECU 20 determines whether or not the water temperature THW1 in the engine 1 detected by the water temperature sensor 9a is higher than a predetermined temperature. This process is a process for determining whether or not the engine 1 has been warmed up. Therefore, this predetermined temperature is a reference temperature for determining whether or not the warm-up of the engine 1 has been completed, and is about 90 ° C., for example. The predetermined temperature is obtained in advance by experiments or the like and stored in a ROM or the like.

  When the ECU 20 determines that the water temperature THW1 in the engine 1 is higher than the predetermined temperature (step S112: Yes), the ECU 20 determines that the engine 1 has been warmed up, and controls the three-way valve 6. Then, the cooling water is circulated through the hot cooling water route passing through the engine 1 (step S113). On the other hand, when the ECU 20 determines that the water temperature THW1 in the engine 1 is equal to or lower than the predetermined temperature (step S112: No), the ECU 20 determines that the engine 1 is warming up and controls the three-way valve 6. Thus, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1 (step S114). Thereby, warm-up of the engine 1 can be promoted. The ECU 20 ends the control process after performing the processes of steps S113 and S114.

  Here, when the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2 during Cold, the ECU 20 distributes the cooling water through the Hot cooling water route passing through the engine 1. The cooling water is not circulated through the Cold cooling water route that bypasses the engine 1. However, it is not limited to this. Instead, a flow distribution three-way valve is used as the three-way valve 6. When the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2 during Cold, the water in the engine 1 is used. The flow rate of the cooling water in the jacket may be increased, and the flow rate of the cooling water in the bypass passage 7d2 that bypasses the engine 1 may be decreased. Also by this, the flow rate of the cooling water in the Hot cooling water route passing through the engine 1 increases, and the required heat amount of the heater core 5 can be satisfied.

  According to the second embodiment described above, warming of the engine 1 can be promoted during Cold, and when the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2, The required heat quantity of the heater core 9 can be satisfied. Thereby, it becomes possible to satisfy the heating requirement. Also, when there is a defroster request and a deice request, the defroster performance and the deice performance can be ensured.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. The configuration of the cooling water control apparatus 100a according to the third embodiment is shown in FIG.

  In the first embodiment described above, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1 by controlling the three-way valve 6 during Cold. However, at this time, the amount of recovered heat of the cooling water in the exhaust heat recovery device 2 is relatively large, and the temperature of the cooling water in the Cold cooling water route that bypasses the engine 1 becomes higher than the temperature of the cooling water in the engine 1. In this case, there is a possibility that the thermostat 4 opens and the heat of the cooling water is dissipated from the radiator 3 and is wasted even though it is Cold.

  Therefore, in the cooling water control apparatus 100a according to the third embodiment, in addition to the components of the cooling water control apparatus 100 according to the first embodiment, the cooling water in the exhaust heat recovery device 2 flows out as shown in FIG. A water temperature sensor 9b is provided in the vicinity of the outlet. The water temperature sensor 9b supplies a detection signal S9b corresponding to the detected water temperature to the ECU 20. When the ECU 20 determines that the coolant temperature THW2 detected by the coolant temperature sensor 9b is higher than the coolant temperature THW1 in the engine 1 based on the detection signal 9b during Cold, the engine 1 It is assumed that the cooling water is circulated through a hot cooling water route passing through the inside.

  Specifically, when the ECU 20 determines that the coolant temperature detected by the coolant temperature sensor 9b is higher than a predetermined temperature during Cold, the ECU 20 controls the three-way valve 6 to switch the coolant route. The cooling water is circulated through the hot cooling water route passing through the engine 1. Here, the predetermined temperature is set to a temperature equal to or lower than the water temperature at which the valve opening of the thermostat 4 starts, for example. In this way, the heat recovered by the exhaust heat recovery device 2 can be supplied to the engine 1 before the thermostat 4 opens, that is, before the radiator 3 radiates heat. Thereby, useless heat dissipation by the radiator 3 can be suppressed, and warm-up of the engine 1 can be promoted.

(Cooling water route switching process)
Next, the cooling water route switching process according to the third embodiment will be described with reference to the flowchart shown in FIG. In the cooling water route switching processing according to the third embodiment, it is determined whether or not the cooling water route switching processing according to the first embodiment described above, that is, the engine 1 has been warmed up, and the cooling water route is determined. In addition to the switching process, a process for determining whether or not the coolant temperature detected by the water temperature sensor 9b is higher than a predetermined temperature (for example, a temperature equal to or lower than the water temperature at which the thermostat 4 starts to open) is performed. Is called. The details will be described below.

  In step S121, the ECU 20 determines whether or not the water temperature THW1 in the engine 1 detected by the water temperature sensor 9a is higher than the first predetermined temperature. This process is a process for determining whether or not the engine 1 has been warmed up. The first predetermined temperature is a reference temperature for determining whether or not the warm-up of the engine 1 is completed, and is about 90 ° C., for example. The first predetermined temperature is obtained in advance by experiments or the like and stored in a ROM or the like.

  In step S121, when the ECU 20 determines that the water temperature THW1 in the engine 1 is higher than the first predetermined temperature (step S121: Yes), the ECU 20 determines that the warm-up of the engine 1 has been completed, The three-way valve 6 is controlled to flow the cooling water through the hot cooling water route passing through the engine 1 (step S123). On the other hand, when it is determined that the water temperature THW1 in the engine 1 is equal to or lower than the first predetermined temperature (step S121: No), the ECU 20 determines that the engine 1 is warming up, and in step S122 Proceed to processing.

  In step S122, the ECU 20 determines whether or not the water temperature THW2 near the outlet of the cooling water in the exhaust heat recovery device 2 detected by the water temperature sensor 9b is higher than the second predetermined temperature. Here, the second predetermined temperature is set to a temperature equal to or lower than the water temperature at which the thermostat 4 starts to open, and is about 78 ° C., for example. The second predetermined temperature is obtained in advance by experiments or the like and stored in a ROM or the like.

  In step S122, when the ECU 20 determines that the water temperature THW2 near the outlet of the cooling water in the exhaust heat recovery device 2 is higher than the second predetermined temperature (step S122: Yes), the process of step S123 is performed. Then, the cooling water is circulated through the cooling water route at the time of hot passing through the engine 1. By doing so, the heat recovered by the exhaust heat recovery device 2 can be supplied to the engine 1 before the thermostat 4 is opened and heat is radiated by the radiator 3.

  On the other hand, when the ECU 20 determines that the water temperature THW2 is equal to or lower than the second predetermined temperature (step S122: No), the ECU 20 controls the three-way valve 6 to perform the Cold cooling water route that bypasses the engine 1. The cooling water is circulated (step S124). The ECU 20 ends the control process after the processes of steps S123 and S124 are performed.

  In the third embodiment described above, the second predetermined temperature is determined in advance, but is not limited to this. Instead, for example, an electronic thermostat that is connected to the ECU 20 as the thermostat 4 and whose valve opening start temperature changes according to the manner of driving by the driver is used, and the ECU 20 sets the second predetermined temperature to the driver's It may be changed according to the way of driving.

  In the third embodiment described above, when the ECU 20 determines that the coolant temperature THW2 detected by the coolant temperature sensor 9b is higher than the coolant temperature THW1 in the engine 1 during Cold. In addition, it is assumed that the cooling water flows through the Hot cooling water route passing through the engine 1 and that the cooling water does not flow through the Cold cooling water route that bypasses the engine 1. However, the present invention is not limited to this. Instead, a flow distribution three-way valve is used as the three-way valve 6, and the ECU 20 uses the coolant temperature THW2 detected by the water temperature sensor 9b to cool the engine 1. If it is determined that the water temperature is higher than the water temperature THW1, the flow rate of the cooling water in the water jacket in the engine 1 may be increased, and the flow rate of the cooling water in the bypass passage 7d2 that bypasses the engine 1 may be decreased. As a result, the flow rate of the cooling water in the Hot cooling water route passing through the engine 1 increases, and the flow rate of the cooling water in the Cold cooling water route that bypasses the engine 1 decreases. Also by this, useless heat radiation by the radiator 3 can be suppressed, and warming up of the engine 1 can be promoted.

  In the third embodiment described above, the water temperature sensor 9b is provided in the vicinity of the outlet from which the cooling water flows out in the exhaust heat recovery device 2, but this is not a limitation, and instead, Cold cooling water is provided. For example, the water temperature sensor 9b may be provided at an arbitrary place on the route, for example, in the vicinity of the inlet into which the cooling water in the exhaust heat recovery device 2 flows. That is, the ECU 20 increases the flow rate of the cooling water in the water jacket in the engine 1 when it is determined that the temperature of the cooling water flowing through the exhaust heat recovery device 2 is higher than the cooling water temperature THW1 in the engine 1. The flow rate of the cooling water in the bypass passage 7d2 that bypasses the engine 1 may be reduced. Also by this, the same effect as the above-mentioned effect can be obtained.

  According to the third embodiment described above, useless heat dissipation by the radiator 3 can be suppressed, and warming up of the engine 1 can be further promoted.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. The configuration of the cooling water control apparatus according to the fourth embodiment is the same as the configuration of the cooling water control apparatus 100 according to the first embodiment shown in FIG.

  In the first embodiment described above, by controlling the three-way valve 6 during Cold, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1, and the Hot cooling that passes through the engine 1 is performed. It was said that cooling water would not be distributed through the water route. Here, when the warm-up of the engine 1 is completed and the cooling water route is switched from the Cold cooling water route to the Hot cooling water route, the temperature of the cooling water flowing into the heater core 5 changes suddenly. Further, the temperature at which the heater core 9 is blown out also changes suddenly, and the driver may feel uncomfortable. This can occur even when the circulation of the cooling water is switched from the hot cooling water route to the cold cooling water route.

  Therefore, in the fourth embodiment, the three-way valve 6 has an intermediate temperature mode in which the cooling water in the water jacket in the engine 1 and the cooling water in the bypass passage 7d2 that bypasses the engine 1 are mixed. Specifically, the intermediate temperature mode means that in the three-way valve 6 shown in FIG. 1, the valve f3 in the direction of the cooling water passage 7f is fully opened, and the bypass passage 7d2 and the cooling water passage 7e are in the respective directions. In the mode in which the valves f1 and f2 are half-opened, or in the three-way valve 6 shown in FIG. 1, the valve f3 in the direction of the cooling water passage 7f is fully open, and the bypass passage 7d2 and the cooling water passage 7e respectively. In this mode, the valves f1 and f2 in the direction of are repeatedly opened and closed alternately in a sufficiently short time.

  When there is a request for switching the cooling water route, the ECU 20 sets the three-way valve 6 to the intermediate temperature mode for a predetermined time and then switches the cooling water route. By doing in this way, the cooling water in the water jacket in the engine 1 and the cooling water in the bypass passage 7d2 that bypasses the engine 1 can be mixed when the cooling water route is switched. By doing in this way, the sudden change of the water temperature of the cooling water which flows into the heater core 5 accompanying switching of a cooling water route can be suppressed, and the sudden change of the blowing temperature of the heater core 5 can be suppressed.

(Cooling water route switching process)
Next, the cooling water route switching process according to the fourth embodiment will be described with reference to the flowchart shown in FIG. In the cooling water route switching processing according to the fourth embodiment, processing for setting the three-way valve 6 to the intermediate temperature mode is performed when switching the cooling water route. The details will be described below.

  In step S131, the ECU 20 determines whether or not there is a request for switching from the Cold coolant route that bypasses the engine 1 to the Hot coolant route that passes through the engine 1. For example, as described in the first embodiment, the ECU 20 determines whether or not the warm-up of the engine 1 has been completed based on the coolant temperature THW1 in the engine 1 to thereby perform the Cold coolant flow route. It is possible to determine whether or not there is a request for switching from the hot water cooling route to the hot.

  In step S131, if the ECU 20 determines that there is a request for switching from the cold cooling water route to the hot cooling water route (step S131: Yes), the process proceeds to step S132.

  In step S132, the ECU 20 determines whether heating is being performed. For example, the ECU 20 can determine whether or not heating is being performed based on the presence or absence of a heating request. If the ECU 20 determines that heating is not being performed (step S132: No), the ECU 20 switches to the hot cooling water route (step S137). On the other hand, when the ECU 20 determines that heating is being performed (step S132: Yes), the three-way valve 6 is set to the intermediate temperature mode (step S133), and after a predetermined time (for example, 5 seconds) has elapsed (step S135). ), Switching to the hot cooling water route (step S137). By doing in this way, the sudden change of the water temperature of the cooling water which flows into the heater core 5 can be suppressed, and the sudden change of the blowing temperature of the heater core 5 can be suppressed. This predetermined time is obtained in advance by experiments or the like and stored in a ROM or the like. The ECU 20 ends the control process after performing the process of step S137.

  If the ECU 20 determines that the coolant temperature THW1 in the engine 1 is higher than the predetermined temperature based on the detection signal from the coolant temperature sensor 9a after the process of step S133 (step S13). S134) Before the predetermined time has elapsed, the intermediate temperature mode of the three-way valve 6 is terminated (step S136), and the hot water cooling water route is switched (step S137). This predetermined temperature is set at a temperature equal to or lower than the boiling point of the cooling water, and is about 100 ° C., for example. This predetermined temperature is obtained in advance by experiments or the like and stored in a ROM or the like. The reason for performing the process of step S134 is that it is necessary to quickly cool the cooling water when the temperature of the cooling water in the engine 1 reaches the boiling point.

  Returning to the process of step S131, the ECU 20 determines that there is no request for switching from the cold coolant route that bypasses the engine 1 to the hot coolant route that passes through the engine 1 (step S131: No). Then, the process proceeds to step S141, and it is determined whether or not there is a request for switching from the Hot cooling water route passing through the engine 1 to the Cold cooling water route bypassing the engine 1. For example, the ECU 20 determines whether or not the engine 1 needs to be warmed up based on the coolant temperature THW1 in the engine 1, thereby requesting switching from the hot coolant route to the cold coolant route. It can be determined whether or not there is. If the ECU 20 determines that there is a request for switching from the hot cooling water route to the cold cooling water route (step S141: Yes), the ECU 20 proceeds to the processing of step S142, and from the hot cooling water route to the cold cooling water route. If it is determined that there is no request for switching to the route (step S141: No), this control process is terminated.

  Since the processing from step S142 to step S146 is the same as the processing from step S132 to step S136, detailed description thereof will be omitted. Briefly, the ECU 20 sets the three-way valve 6 to the intermediate temperature mode (step S143), when a predetermined time (for example, 5 seconds) has elapsed (step S145), or the cooling water temperature in the engine 1 When it is determined that THW1 is higher than a predetermined temperature (for example, 100 ° C.) (step S144), switching to the cold cooling water route is performed (step S147). By doing in this way, the sudden change of the water temperature of the cooling water which flows into the heater core 5 can be suppressed, and the sudden change of the blowing temperature of the heater core 5 can be suppressed. The ECU 20 ends the control process after performing the process of step S147.

  According to the fourth embodiment described above, it is possible to suppress a sudden change in the temperature of the cooling water flowing into the heater core 5 due to the switching of the cooling water route, and to suppress a sudden change in the blowing temperature of the heater core 5. it can.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described. The configuration of the cooling water control apparatus 100b according to the fifth embodiment is shown in FIG.

  In the first embodiment described above, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1 by controlling the three-way valve 6 during Cold. At this time, as shown in FIG. 1, in the cooling water control apparatus 100 according to the first embodiment, the cooling water recovered by the exhaust heat recovery device 2 passes through the cooling water passages 7a, 7b, 7d2, and 7f. After that, the heater core 5 is reached. However, at this time, the cooling water whose heat has been recovered by the exhaust heat recovery device 2 is dissipated before reaching the heater core 5. Specifically, the cooling water dissipates heat when passing through the cooling water passages 7a, 7b, 7d2, and 7f. Therefore, in the cooling water control apparatus 100 according to the first embodiment, it may be difficult to satisfy the required heat amount of the heater core 5.

  Therefore, in the cooling water control apparatus 100b according to the fifth embodiment, unlike the cooling water control apparatus 100 according to the first embodiment, the heater core 5 is provided on the downstream side of the exhaust heat recovery device 2 as shown in FIG. It shall be provided on the water passage 7a. In this case, as shown in FIG. 7, the cooling water whose heat has been recovered by the exhaust heat recovery device 2 is more in comparison with the cooling water control device 100 according to the first embodiment before reaching the heater core 5. The cooling water passage 7 (a part of the cooling water passage 7a) of a short distance is passed. Therefore, in the cooling water control apparatus 100b according to the fifth embodiment, compared with the cooling water control apparatus 100 according to the first embodiment, the heat radiation of the cooling water in the cooling water passage 7 can be minimized, and the heater core The heat radiation amount in 5 can be increased.

  Further, in the cooling water control apparatus 100b according to the fifth embodiment, the water temperature sensor 9b for detecting the cooling water temperature in the cooling water passage downstream of the engine 1 and upstream of the exhaust heat recovery device 2. Is provided. In this way, the ECU 20 compares the coolant temperature THW1 in the engine 1 detected by the coolant temperature sensor 9a with the coolant temperature THW2 detected by the coolant temperature sensor 9b. It is possible to determine whether one of 9a and 9b is out of order. Specifically, when the water temperature THW1 and the water temperature THW2 substantially match, the ECU 20 can determine that both the water temperature sensors 9a and 9b are functioning normally. On the other hand, when the water temperature THW1 and the water temperature THW2 are largely different, the ECU 20 can determine that one of the water temperature sensors 9a and 9b has failed.

  When it is determined that one of the water temperature sensors 9a and 9b has failed, the ECU 20 passes through the engine 1 instead of the Cold cooling water route that bypasses the engine 1 during cold start. The cooling water is circulated through the hot cooling water route. Then, the ECU 20 detects the water temperature increase degree for each of the water temperature THW1 detected by the water temperature sensor 9a and the water temperature THW2 detected by the water temperature sensor 9b. Here, the ECU 20 can also estimate the degree of increase in the coolant temperature in the engine 1 based on the fuel consumption of the engine 1. Therefore, the ECU 20 identifies the problematic water temperature sensor by comparing the degree of increase in the detected water temperatures THW1 and THW2 with the degree of increase in the coolant temperature estimated based on the fuel consumption. be able to.

(Modification of the fifth embodiment)
Here, a modification of the fifth embodiment will be described. The configuration of a cooling water control apparatus 100ba according to a modification of the fifth embodiment is shown in FIG. In the cooling water control apparatus 100b according to the fifth embodiment described above, the heater core 5 is provided in the cooling water passage 7a on the downstream side of the exhaust heat recovery device 2. Therefore, bubbles generated when the cooling water boils in the exhaust heat recovery device 2 may flow into the heater core 5. In this case, abnormal noise may be generated in the heater core 5 and the driver may feel uncomfortable.

  Therefore, in the cooling water control apparatus 100ba according to the modification of the fifth embodiment, in addition to the components of the cooling water control apparatus 100b, the cooling water passage 7a between the exhaust heat recovery device 2 and the heater core 5 is connected to the cooling water. A water temperature sensor 9c for detecting the water temperature is provided. The water temperature sensor 9c supplies the ECU 20 with a detection signal S9c corresponding to the detected water temperature THW3. If the ECU 20 determines that the coolant temperature THW3 detected by the coolant temperature sensor 9c is higher than the predetermined temperature, the ECU 20 determines that the coolant may boil and controls the electric WP8 to control the coolant passage 7a. Let's increase the flow rate of the cooling water. Here, the predetermined temperature is set to a temperature lower than the boiling point of the cooling water, and is about 110 ° C., for example. This predetermined temperature is obtained in advance by experiments or the like and stored in a ROM or the like. By doing in this way, it can suppress that the cooling water in the exhaust heat recovery device 2 boils, and the noise which generate | occur | produces in the heater core 5 by a bubble flowing into the heater core 5 can be prevented.

  Further, by providing the water temperature sensor 9c in the cooling water passage between the exhaust heat recovery device 2 and the heater core 5, it is possible to detect the boiling of the cooling water in the exhaust heat recovery device 2 during the dead soak.

[Sixth Embodiment]
Next, a cooling water control apparatus according to a sixth embodiment of the present invention will be described. The configuration of the cooling water control apparatus 100c according to the sixth embodiment is shown in FIG.

  In the first embodiment described above, by controlling the three-way valve 6 during Cold, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1, and the Hot cooling that passes through the engine 1 is performed. It was said that cooling water would not be distributed through the water route. However, in a state where there is little exhaust loss such as during light load traveling, the amount of heat recovered by the exhaust heat recovery device 2 is smaller than the required amount of heat of the heater core 5. Conversely, similarly to the case of the second embodiment, the heater core 5 The required amount of heat becomes larger than the amount of heat recovered by the exhaust heat recovery unit 2, and the required amount of heat of the heater core 5 cannot be satisfied only by circulating the cooling water through the Cold cooling water route that bypasses the engine 1.

  Therefore, in the cooling water control apparatus 100c according to the sixth embodiment, the ECU 20 determines whether the amount of heat recovered by the exhaust heat recovery device 2 is smaller than the required amount of heat of the heater core 5 based on the intake air amount (inversely speaking). As in the second embodiment, it is determined whether or not the required heat amount of the heater core 5 is larger than the recovered heat amount by the exhaust heat recovery device 2. Specifically, first, the ECU 20 calculates the intake air amount based on the detection signal S11 from the air flow sensor (A / F sensor) 11. The ECU 20 determines that the amount of heat recovered by the exhaust heat recovery device 2 is smaller than the required heat amount of the heater core 5 when it is determined that the intake air amount is smaller than a predetermined amount during Cold. Here, the predetermined amount is a value that can be predicted that when the intake air amount becomes smaller than this value, the amount of heat recovered by the exhaust heat recovery device 2 becomes smaller than the required heat amount of the heater core 5.

  When the ECU 20 determines that the amount of intake air is smaller than the predetermined amount, that is, when it is determined that the amount of heat recovered by the exhaust heat recovery device 2 is smaller than the required amount of heat of the heater core 5, the time of Hot passing through the engine Cooling water will be circulated through the cooling water route. By doing so, the exhaust loss is small as in light load traveling or the like, and therefore when the amount of heat recovered by the exhaust heat recovery device 2 is smaller than the required heat amount of the heater core 5, the combustion heat of the engine 1 Heated relatively high-temperature cooling water can be supplied to the heater core 5, and the required heat amount of the heater core 5 can be satisfied.

(Cooling water route switching control process)
Next, the cooling water route switching process according to the sixth embodiment will be described with reference to the flowchart shown in FIG. In the cooling water route switching control process according to the sixth embodiment, when it is determined that the intake air amount is smaller than a predetermined amount during Cold, the ECU 20 performs cooling with the Hot cooling water route that passes through the engine. Water will be distributed.

  In step S201, the ECU 20 determines whether or not the intake air amount obtained based on the detection signal S11 from the A / F sensor 11 is smaller than a predetermined amount. This predetermined amount is a value that can be predicted that when the intake air amount becomes smaller than this value, the amount of heat recovered by the exhaust heat recovery device 2 becomes smaller than the required heat amount of the heater core 5, for example, about 3 g / sec. is there. This predetermined amount is obtained in advance by experiments or the like and recorded in a ROM or the like.

  In step S201, when the ECU 20 determines that the intake air amount is smaller than the predetermined amount (step S201: Yes), the ECU 20 determines that the recovered heat amount by the exhaust heat recovery device 2 is smaller than the required heat amount of the heater core 5, The three-way valve 6 is controlled, the cooling water route is switched, and the cooling water is circulated through the hot cooling water route passing through the engine 1 (step S202). Thereby, relatively high-temperature cooling water heated by the combustion heat of the engine 1 can be supplied to the heater core 5. On the other hand, when the ECU 20 determines that the intake air amount is greater than or equal to the predetermined amount (step S201: No), the cooling water route is not switched and the cooling water route that bypasses the engine 1 remains the cooling water route. Is distributed (step S203). ECU20 complete | finishes this control process, after performing the process of step S201, S203.

  In the sixth embodiment described above, the ECU 20 determines whether or not the amount of heat recovered by the exhaust heat recovery device 2 is smaller than the required amount of heat of the heater core 5 based on the intake air amount. It is not limited to. Instead of based on the intake air amount, it may be determined whether the amount of heat recovered by the exhaust heat recovery device 2 is smaller than the required amount of heat of the heater core 5 based on the amount of fuel. Thereby, even if the air-fuel ratio fluctuates, it can be accurately determined. Alternatively, the exhaust loss is estimated by measuring the exhaust temperature instead of based on the intake air amount, and the recovered heat amount by the exhaust heat recovery device 2 is smaller than the required heat amount of the heater core 5 based on the estimated exhaust loss. It may be determined whether or not. Thereby, even if it is a case where a combustion state changes and an exhaust loss ratio changes, it can determine correctly.

  Further, in the sixth embodiment described above, when it is determined that the intake air amount is smaller than the predetermined amount, the ECU 20 distributes the cooling water through the Hot cooling water route passing through the engine. That is, the cooling water is not circulated through the cold cooling water route. However, the present invention is not limited to this. Instead, the flow distribution three-way valve is used as the three-way valve 6, and the ECU 20 determines that the intake air amount is smaller than the predetermined amount. The flow rate of the cooling water in the water jacket may be increased, and the flow rate of the cooling water in the bypass passage 7d2 that bypasses the engine 1 may be decreased. In other words, the flow rate of the cooling water in the Hot-time cooling water route passing through the engine 1 may be increased, and the flow rate of the cooling water in the Cold-time cooling water route that bypasses the engine 1 may be decreased. Even in this case, the required heat amount of the heater core 5 can be satisfied.

  According to the sixth embodiment described above, when the amount of heat recovered by the exhaust heat recovery device 2 is smaller than the required heat amount of the heater core 5 due to a decrease in exhaust loss, such as during light load traveling, the engine The relatively high-temperature cooling water heated by the combustion heat of 1 can be supplied to the heater core 5. Thereby, the request | requirement calorie | heat amount of the heater core 5 can be satisfy | filled, and a heating request | requirement etc. can be satisfy | filled. Moreover, a time lag in switching control can be prevented by predicting a decrease in the amount of recovered heat by the exhaust heat recovery device 2 based on the intake air amount and performing the above-described cooling water route switching control.

[Seventh Embodiment]
Next, a cooling water control apparatus according to a seventh embodiment of the present invention will be described. The configuration of the cooling water control apparatus according to the seventh embodiment is the same as the configuration of the cooling water control apparatus 100c according to the sixth embodiment.

  In the sixth embodiment described above, when the intake air amount is smaller than the predetermined amount, the cooling water is circulated through the Hot cooling water route passing through the engine 1. However, if the cooling water is circulated through the hot cooling water route following a temporary decrease in the intake air amount such as temporarily turning off the accelerator during traveling, the warm-up of the engine 1 is hindered. There is a risk.

  Therefore, in the seventh embodiment, even when the ECU 20 determines that the intake air amount is smaller than the first predetermined amount during Cold, the integrated amount (hereinafter referred to as “integrated amount”) of the intake air amount for a predetermined time is determined. If it is determined that the intake air amount is larger than the second predetermined amount, it is prohibited to circulate the cooling water through the hot cooling water route. That is, the cooling water is circulated through the Cold cooling water route. Here, the first predetermined amount corresponds to the predetermined amount in the sixth embodiment, and when the intake air amount becomes smaller than this value, the recovered heat amount by the exhaust heat recovery device 2 becomes smaller than the required heat amount of the heater core 5. It is a value that can be predicted. The second predetermined amount is a value that can be determined as a temporary decrease in the intake air amount when the integrated intake air amount is greater than this value. By doing in this way, the influence by the fluctuation | variation of a temporary intake air amount can be excluded, and warming-up promotion of the engine 1 can be aimed at.

(Cooling water route switching control process)
Next, the cooling water route switching process according to the seventh embodiment will be described with reference to the flowchart shown in FIG. In the cooling water route switching control process according to the seventh embodiment, even when it is determined that the intake air amount is smaller than the first predetermined amount at Cold, the integrated amount of the intake air amount in the predetermined time is determined. When it is determined that the second predetermined amount or more is reached, it is prohibited to circulate the cooling water through the Hot cooling water route passing through the engine 1, and the Cold cooling water bypassing the engine 1 is bypassed. Cooling water will be distributed along the route.

  In step S211, the ECU 20 determines whether or not the intake air amount obtained based on the detection signal from the A / F sensor 11 is smaller than the first predetermined amount. When the ECU 20 determines that the intake air amount is greater than or equal to the first predetermined amount (step S211: No), the ECU 20 causes the cooling water to flow in the Cold cooling water route that bypasses the engine 1 (step S211). S214). Here, the first predetermined amount is a value that can be predicted that when the intake air amount becomes smaller than this value, the amount of heat recovered by the exhaust heat recovery device 2 becomes smaller than the required amount of heat of the heater core 5, for example, It is about 3 g / sec. This first predetermined amount is obtained in advance by experiments or the like and recorded in a ROM or the like.

  In step S211, when the ECU 20 determines that the intake air amount is smaller than the first predetermined amount (step S211: Yes), the integrated amount of the intake air amount for a predetermined time, that is, the integrated air amount is the second. It is determined whether or not the predetermined amount is larger (step S212). Here, the second predetermined amount is a value that can be determined to be a temporary decrease in the intake air amount when the integrated intake air amount is larger than this value, and is, for example, about 30 g. The second predetermined amount is obtained in advance by experiments or the like and recorded in a ROM or the like. Further, the predetermined time is also obtained in advance by experiments or the like and recorded in a ROM or the like.

  In step S212, when the ECU 20 determines that the integrated air amount is larger than the second predetermined amount (step S212: Yes), the ECU 20 determines that the intake air amount is temporarily reduced, and the engine The cooling water is circulated in the Cold cooling water route that bypasses 1 (step S214). On the other hand, if the ECU 20 determines that the accumulated air amount is equal to or less than the second predetermined amount (step S212: No), the ECU 20 determines that the intake air amount has not temporarily decreased and controls the three-way valve 6. The cooling water is circulated through the hot cooling water route passing through the engine 1 (step S213). By the process of step S212, it is possible to exclude the influence due to the temporary fluctuation of the intake air amount, and it is possible to promote the warm-up of the engine 1.

  The ECU 20 performs the processes of steps S213 and S214, resets the integrated air amount (step S215), and ends this control process.

  In the seventh embodiment described above, even when the ECU 20 determines that the intake air amount is smaller than the first predetermined amount during Cold, the integrated amount of the intake air amount in the predetermined time is the second amount. When it is determined that the amount is larger than the predetermined amount, it is prohibited to circulate the cooling water through the hot cooling water route. However, the present invention is not limited to this. Instead, a flow distribution three-way valve is used as the three-way valve 6, and the ECU 20 determines that the intake air amount is smaller than the first predetermined amount at Cold. However, if it is determined that the integrated amount of the intake air amount in the predetermined time is larger than the second predetermined amount, it is prohibited to increase the flow rate of the cooling water in the water jacket in the engine 1. In other words, it may be prohibited to increase the flow rate of the cooling water in the hot cooling water route passing through the engine 1. Even in this case, it is possible to eliminate the influence due to the temporary fluctuation of the intake air amount, and it is possible to promote the warm-up of the engine 1.

  According to the seventh embodiment described above, it is possible to exclude the influence due to the temporary fluctuation of the intake air amount, and to promote warm-up of the engine 1.

[Eighth Embodiment]
Next, a cooling water control apparatus according to an eighth embodiment of the present invention will be described. The configurations of the cooling water control devices 100da and 100db according to the eighth embodiment are shown in FIGS. 12 and 13, respectively. 12 and 13, the heater blower 5 a is a heater blower of the heater core 5. The heater blower 5a is controlled by a control signal S5a from the ECU 20.

  In the first embodiment described above, by controlling the three-way valve 6 during Cold, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1, and the Hot cooling that passes through the engine 1 is performed. It was said that cooling water would not be distributed through the water route. At this time, since the flow of the cooling water in the engine 1 is stopped, the water temperature of the cooling water in the engine 1 detected by the water temperature sensor 9 a circulates through the Cold cooling water route that bypasses the engine 1. The temperature is higher than that of the cooling water. Accordingly, at this time, when the coolant temperature in the engine 1 reaches a general heater blower operating temperature (for example, 40 ° C.), the coolant supplied to the heater core 5 (the coolant in the Cold coolant route) is supplied. The water temperature is lower than this operating temperature. For this reason, when the heater blower 5a is operated when the coolant temperature in the engine 1 reaches the general operating temperature of the heater blower, a low-temperature wind blows out from the heater core 5, giving the driver an unpleasant feeling. There is a fear. In view of this, when the temperature of the cooling water in the engine 1 is higher than a general heater blower operating temperature (for example, 80 ° C.), the heater blower 5a is set to operate. Even if the temperature of the cooling water supplied to the heater core 5 reaches a general heater blower operating temperature, the heater blower 5a may not operate. As described above, when the heater blower 5a is controlled based on the coolant temperature in the engine 1, the heating performance may be deteriorated.

  Therefore, in the eighth embodiment, during Cold, the heater blower air volume of the heater core 5 is controlled based on the water temperature in the vicinity of the inlet through which the cooling water flows in the heater core 5 (hereinafter simply referred to as “heater core inlet water temperature”). To do.

  First, there are two possible methods for obtaining the heater core inlet water temperature. The first method is, for example, a method of providing a water temperature sensor 9b on the cooling water passage 7f near the inlet into which the cooling water flows in the heater core 5, as shown in the cooling water control device 100da of FIG. In this way, the ECU 20 can obtain the heater core inlet water temperature based on the detection signal S9b from the water temperature sensor 9b.

  The second method is to obtain the intake air amount based on the detection signal S11 from the A / F sensor 11 as shown in the cooling water control device 100db of FIG. ) And the integrated value of the heater blower air volume (integrated heater blower air volume). Thereby, the heater core inlet water temperature can be obtained without providing a water temperature sensor on the cooling water passage 7f near the inlet through which the cooling water flows in the heater core 5.

  Here, the heater core inlet water temperature estimation method will be specifically described. In the Cold cooling water route that bypasses the engine 1, the rising temperature of the cooling water from the start of the engine 1 is calculated by integrating the heat dissipation amount of the heater core 5 from the integrated value of the recovered heat amount recovered by the exhaust heat recovery device 2. It is proportional to the value obtained by subtracting the value (integrated value of recovered heat amount−integrated value of heat release amount). Here, the integrated value of the recovered heat amount is proportional to the integrated intake air amount, and the integrated value of the heat dissipation amount of the heater core 5 is proportional to the integrated heater blower air amount. Therefore, assuming that the proportionality constants are A and B, and the coolant temperature at the start of the engine 1 is the coolant temperature STHW, the heater core inlet coolant temperature HTHW can be calculated by the following equation (1). The proportional constants A and B are determined in advance by experiments or the like and are recorded in a ROM or the like.

HTHW = A × integrated intake air amount−B × integrated heater blower air amount + STHW (1)
Accordingly, the ECU 20 obtains the integrated intake air amount based on the detection signal S11 from the A / F sensor 11, and obtains the integrated heater blower air amount based on the control signal supplied to the heater blower 5a, and obtains the equation (1). The heater core inlet water temperature HTHW can be estimated by substituting the obtained integrated intake air amount and integrated heater blower air volume. Accordingly, as shown in FIG. 13, the heater core inlet water temperature HTHW can be estimated without newly providing a water temperature sensor in the vicinity of the inlet through which the coolant of the heater core 5 flows.

  The ECU 20 controls the heater blower air volume by controlling the heater blower 5a based on the heater core inlet water temperature obtained using any one of the two methods for obtaining the heater core inlet water temperature described above. Specifically, the ECU 20 obtains the heater blower air volume based on the heater core inlet water temperature HTHW using the following equation (2), and then controls the heater blower 5a to adjust to the obtained heater blower air quantity. Note that the constant C is also determined in advance through experiments or the like and recorded in a ROM or the like.

Heater blower air flow = Maximum heater blower air flow-C x (HTHW-Heater blower operating temperature) (2)
Thus, by controlling the heater blower air volume of the heater core 5 based on the heater core inlet water temperature in the heater core 5, it is possible to prevent the heating performance of the heater core 5 from deteriorating.

(Heater blower air volume control process)
A process for estimating the heater core inlet water temperature using the equation (1) and controlling the heater blower air volume based on the estimated heater core inlet water temperature will be described with reference to the flowchart shown in FIG. In FIG. 14, “blower air volume” indicates the heater blower air volume, and “GA” indicates the intake air volume.

  In step S301, the ECU 20 determines whether or not the engine 1 is being started based on the operating state of the engine 1 or the like. If the ECU 20 determines that the engine 1 is not being started (step S301: No), the ECU 20 proceeds to the process of step S303. When the ECU 20 determines that the engine 1 is being started (step S301: Yes), the coolant temperature THW1 in the engine 1 detected by the water temperature sensor 9a is used as the water temperature STHW when the engine 1 is started. After setting (step S302), the process proceeds to step S303.

  In step S303, the ECU 20 circulates the cooling water in the Cold cooling water route that bypasses the engine 1 based on, for example, the control signal S6 supplied to the three-way valve 6 or the like. It is determined whether or not. When it is determined that the control is not being performed during Cold, that is, the cooling water is not being circulated through the Cold cooling water route (step S303: No), the ECU 20 is causing the cooling water to be circulated through the Hot cooling water route. Therefore, the coolant temperature THW1 in the engine 1 is set as the heater core inlet water temperature HTHW, and the integrated heater blower air volume and the integrated intake air volume are set to 0 (step S307). On the other hand, if it is determined that the cooling water is being circulated through the Cold cooling water route (Step S303: Yes), the ECU 20 proceeds to the processing of Step S304.

  In step S304, the ECU 20 obtains the intake air amount on the basis of the detection signal S11 from the A / F sensor 11, and then calculates the obtained intake air amount to the integrated intake obtained in the previously executed control process. Add to the air volume. In step S305, the ECU 20 obtains the heater blower air volume based on the control signal supplied to the heater core 5, and then adds the obtained heater blower air volume to the integrated heater blower air quantity obtained in the previously executed control process. In step S306, the ECU 20 substitutes the water temperature STHW obtained in step S302, the accumulated intake air amount obtained in step S304, and the accumulated heater blower air amount obtained in step S305 into the equation (1), thereby obtaining the heater core inlet. Obtain the water temperature HTHW. In this way, the heater core inlet water temperature HTHW can be estimated without newly providing a water temperature sensor near the inlet through which the coolant of the heater core 5 flows.

  In step S308, the ECU 20 determines whether or not the heater core inlet water temperature HTHW is higher than the operating temperature of the heater blower 5a, and if it is determined that the heater core inlet water temperature HTHW is equal to or lower than the operating temperature (step S308: No), the operation of the heater blower 5a is stopped (step S210). Here, the operating temperature is set to a temperature higher than the human body temperature, and is about 40 ° C., for example. The operating temperature is obtained in advance by experiments or the like and recorded in a ROM or the like. On the other hand, when it is determined that the heater core inlet water temperature HTHW is higher than the operating temperature (step S308: Yes), the ECU 20 controls the heater blower 5a to adjust the heater blower air volume. Specifically, the ECU 20 obtains the heater blower air volume using the equation (2), and adjusts the heater blower air volume of the heater blower 5a to the heater blower air volume obtained using the equation (2) (step S309). Thereby, deterioration of the heating performance of the heater core 5 can be prevented. Thereafter, the ECU 20 ends this control process.

  According to the eighth embodiment described above, deterioration of the heating performance of the heater core 5 during Cold can be prevented.

[Ninth Embodiment]
Next, a cooling water control apparatus according to a ninth embodiment of the present invention will be described. The configuration of the cooling water control apparatus 100e according to the ninth embodiment is shown in FIG. In the cooling water control apparatus 100e according to the ninth embodiment, in addition to the water temperature sensor 9a that detects the water temperature in the engine 1, the water temperature sensor 9b is provided in the cooling water passage 7f on the upstream side of the heater core 9. The water temperature sensor 9b detects the water temperature THW2 near the inlet of the cooling water flowing into the heater core 5.

  In the first embodiment described above, it is determined whether or not the coolant temperature THW1 in the engine 1 detected by the coolant temperature sensor 9a is higher than a predetermined temperature (for example, 90 ° C.), and the coolant temperature sensor 9a is used. If it is determined that the detected water temperature THW1 is higher than the predetermined temperature, it is determined that the warm-up has been completed, and the cooling water is circulated through the Hot cooling water route passing through the engine 1, and the water temperature THW1 Is determined to be below the predetermined temperature, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1.

However, since the water temperature sensor 9a is attached to the engine 1, when the flow of the cooling water in the engine 1 is stopped, the water temperature sensor 9a indicates a water temperature close to the temperature of the metal constituting the engine 1 body. The coolant temperature in the engine 1 cannot be accurately detected. Hereinafter, specific description will be given with reference to FIG. 16. FIGS. 16A and 16B are graphs showing changes in the coolant temperature with time. FIG. 16A is a graph showing changes in the water temperatures THW1, THW2, and the water temperature in the vicinity of the cooling water sensor 9a with respect to each time when the cooling water route is switched based on the water temperature THW1 detected by the water temperature sensor 9a. It is.

  At the first Cold, the cooling water flows through the Cold cooling water route that bypasses the engine 1, and the cooling water in the engine 1 stops flowing. Therefore, the water temperature of the cooling water on the cylinder head side is likely to be heated by the combustion heat of the engine 1 and thus rises with time. However, the coolant temperature on the cylinder block side away from the cylinder head is hardly heated by the combustion heat of the engine 1 and therefore does not rise so much. Here, the temperature of the cooling water on the cylinder block side includes the temperature of the cooling water in the cooling water passage 7d1 in which the circulation of the cooling water is stopped during Cold. This is because the water temperature of the cooling water in the cooling water passage 7d1 is hardly heated by the combustion heat of the engine 1.

  Since the water temperature sensor 9a is attached at a position close to the cylinder head of the engine 1, the water temperature sensor 9a detects the coolant temperature of the cylinder head. Therefore, at the Cold time, the water temperature THW1 detected by the water temperature sensor 9a increases with the passage of time. Here, in FIG. 16A, the water temperature in the vicinity of the water temperature sensor 9a refers to the water temperature at a location slightly away from the water temperature sensor 9a. Specifically, the water temperature in the vicinity of the water temperature sensor 9a indicates an intermediate water temperature between the water temperature on the cylinder head side and the water temperature on the cylinder block side. Accordingly, the water temperature THW1 is higher than the water temperature in the vicinity of the water temperature sensor 9a because it indicates the water temperature of the cooling water on the cylinder head side.

  Further, at the first Cold time, the water temperature THW2 detected by the water temperature sensor 9b flows into the heater core 5 through the bypass heat path 2d2 from the exhaust heat recovery device 2 through the coolant temperature in the Cold cooling water route, that is, the coolant temperature. It becomes the water temperature of the cooling water. Accordingly, the water temperature THW2 rises as time elapses as the cooling water is heated by the exhaust heat recovery device 2.

  When the water temperature THW1 detected by the water temperature sensor 9a becomes higher than the first predetermined temperature (for example, 90 ° C.), the ECU 20 determines that the warm-up is completed, that is, the hot water is reached. Switch the route to the hot water route. At this time, since the cooling water in the engine 1 is circulated, the heated cooling water on the cylinder head side is pushed out from the inside of the engine 1, and the water temperature sensor 9a is cooled on the engine block side during Cold. It will detect the water temperature. Therefore, the water temperature THW1 decreases immediately after the hot time. Further, at this time, the cooling water that has been on the engine block side during Cold flows out into the cooling water passage 7f, so that the water temperature THW2 detected by the water temperature sensor 9b also decreases.

  Next, when the water temperature THW1 detected by the water temperature sensor 9a becomes lower than the second predetermined temperature (for example, 50 ° C., which is higher than the body temperature), the ECU 20 warms up. As necessary, the cooling water route is switched to the Cold cooling water route. As a result, the cooling water in the engine 1 does not flow out to the cooling water passage 7f, and the cooling water heated by the exhaust heat recovery device 2 flows into the heater core 5 through the bypass passage 7d2. Accordingly, the water temperature THW2 detected by the water temperature sensor 9b rises again. Further, the temperature THW1 of the cooling water in the engine 1 also rises by being heated by the combustion heat of the engine 1.

  However, if the ECU 20 does not switch the cooling water route to the Cold cooling water route until the water temperature THW1 detected by the water temperature sensor 9a becomes lower than the second predetermined temperature in the Hot state, FIG. As shown in FIG. 5, a state occurs in which the water temperature THW2 becomes lower than the second predetermined temperature during Hot. This is because, as described above, the water temperature THW1 indicates the coolant temperature on the cylinder head side and is higher than the coolant temperature THW2 near the inlet of the coolant flowing into the heater core 5. At this time, since the cooling water having a water temperature lower than the second predetermined temperature flows into the heater core 5, when the vehicle interior is being heated, the heating air that feels cold is blown out from the heater core 5. May be uncomfortable.

  Therefore, in the cooling water control apparatus 100e according to the ninth embodiment, the ECU 20 causes the water temperature sensor 9b to detect the water temperature THW1 detected by the water temperature sensor 9a at the time of Hot, even if the water temperature THW1 is higher than the second predetermined temperature. When the detected water temperature THW2 is lower than the second predetermined temperature, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1.

  FIG. 16B is a graph when the cooling water route is switched based on the water temperature THW1 detected by the water temperature sensor 9a and the water temperature THW2 detected by the water temperature sensor 9b, that is, according to the ninth embodiment. The graph at the time of performing a cooling water route switching process is shown.

  As shown in FIG. 16 (b), in the ninth embodiment, the ECU 20 sets the cooling water route when the water temperature THW2 detected by the water temperature sensor 9b is lower than the second predetermined temperature in the hot state. Switch to the Cooling Water Route during Cold. By doing in this way, it can suppress that water temperature THW2 of the cooling water which flows into the heater core 5 becomes lower than 2nd predetermined temperature, and when the vehicle interior is heating, it is said that it is cooler than the heater core 5. It is possible to suppress the heating air that you feel from blowing out.

(Cooling water route switching process)
Next, the cooling water route switching process according to the ninth embodiment will be described with reference to the flowchart shown in FIG. In the cooling water route switching control process according to the ninth embodiment, in addition to the process of determining whether or not the engine 1 has been warmed up and switching the cooling water route, the water temperature THW2 detected by the water temperature sensor 9b is the second. When the temperature is lower than the predetermined temperature, a process of circulating the cooling water through the Cold cooling water route that bypasses the engine 1 is performed.

  In step S401, the ECU 20 determines whether or not it is hot, that is, whether or not cooling water is circulated through the hot cooling water route passing through the engine 1. The ECU 20 determines that the cooling water is not distributed through the hot cooling water route (step S401: No), that is, the cooling water is determined to be distributed through the cold cooling water route that bypasses the engine 1. In that case, the process proceeds to step S403.

  In step S403, the ECU 20 determines whether or not the water temperature THW1 detected by the water temperature sensor 9a is higher than the first predetermined temperature. When the ECU 20 determines that the water temperature THW1 detected by the water temperature sensor 9a is higher than the first predetermined temperature (step S403: Yes), the ECU 20 circulates the cooling water through the hot cooling water route (step S405). ), When it is determined that the water temperature THW1 is equal to or lower than the first predetermined temperature (step S403: No), this control process is terminated. That is, the process in step S403 is a process for determining whether or not the engine 1 has been warmed up. Accordingly, the first predetermined temperature is a reference temperature for determining whether or not the engine 1 has been warmed up, and is about 90 ° C., for example. The first predetermined temperature is obtained in advance by experiments or the like and stored in a ROM or the like.

  In step S401, if the ECU 20 determines that the cooling water is being circulated through the hot cooling water route (step S401: Yes), the process proceeds to step S402. In Step S402, when it is determined that the water temperature THW2 detected by the water temperature sensor 9b is lower than the second predetermined temperature (Step S402: Yes), the ECU 20 causes the cooling water to flow through the Cold cooling water route. (Step S404), and when it is determined that the water temperature THW2 is equal to or higher than the second predetermined temperature (step S402: No), this control process is terminated. Here, the second predetermined temperature is higher than the human body temperature, and is set to 50 ° C., for example. The second predetermined temperature is obtained in advance by experiments or the like and recorded in a ROM or the like. By doing so, it is possible to prevent the temperature of the cooling water flowing into the heater core 5 from becoming lower than the second predetermined temperature at the time of hot, and when the vehicle interior is being heated, the heater core 5 The heating air that feels cold can be prevented from blowing out.

  In the ninth embodiment described above, when it is determined that the water temperature THW2 detected by the water temperature sensor 9b is lower than the second predetermined temperature at the time of Hot, the Cold cooling water route that bypasses the engine 1 is used. It was supposed to circulate cooling water. However, the present invention is not limited to this. Instead, the flow rate distribution three-way valve may be used as the three-way valve 6 to adjust the flow rate of the cooling water in each route. Specifically, the ECU 20 uses the three-way valve 6 and determines that the water temperature THW2 detected by the water temperature sensor 9b is lower than the second predetermined temperature during the hot state, the cooling water in the bypass passage 7d2 It is possible to increase the flow rate of the cooling water in the Cold cooling water route and decrease the flow rate of the cooling water in the engine 1. Also by this, the temperature of the cooling water flowing into the heater core 5 can be suppressed from becoming lower than the second predetermined temperature, and the heating air that feels cold is blown out from the heater core 5 when the vehicle interior is being heated. Can be suppressed.

  According to the above ninth embodiment, it is possible to prevent the coolant temperature flowing into the heater core 5 from becoming lower than the second predetermined temperature. When the vehicle interior is being heated, the heater core 5 It is possible to prevent the heating air that feels cold from blowing out.

[Tenth embodiment]
Next, a cooling water control apparatus according to a tenth embodiment of the present invention will be described. The configuration of the cooling water control apparatus 100f according to the tenth embodiment is shown in FIG.

  In the first embodiment described above, by controlling the three-way valve 6 during Cold, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1, and the Hot cooling that passes through the engine 1 is performed. It was said that cooling water would not be distributed through the water route. At this time, since the cooling water in the engine 1 is not circulating, it is likely to boil due to the combustion heat of the engine 1, bubbles are generated, the pressure in the cooling water passage 7 is increased, and there is a risk of causing cooling water leakage. is there. However, since the cooling water in the engine 1 does not circulate, the radiator 3 cannot radiate heat and it is difficult to reduce the pressure in the cooling water passage 7. Further, when water vapor is discharged from the cooling water passage 7 by using a pressure valve or the like, the discharged steam adheres to the peripheral parts, which may cause deterioration and failure of the peripheral parts. May be promoted.

  Therefore, in the cooling water control apparatus 100f according to the tenth embodiment, as shown in FIG. 18, in addition to the components of the cooling water control apparatus 100 according to the first embodiment, an air recovery device connected in the engine 1 15 is provided. The air recovery device 15 is a device for recovering bubbles generated in the cooling water in the engine 1 and is connected to the water jacket in the engine 1 via the air recovery passage 7bs.

  Here, the configuration of the air recovery unit 15 will be described in detail with reference to FIG. FIG. 19 is a cross-sectional view showing the internal structures of the air recovery unit 15 and the engine 1.

  The engine 1 has a plurality of cylinders 31, and in each cylinder 31, a piston 33 is installed so as to be operable in the vertical direction of the cylinder 31. A cylinder head 32 is mounted on the top of the cylinder 31. In the engine 1, a water jacket 37 is provided so as to enclose the cylinder 31 and the cylinder head 32. In FIG. 19, hatching in the water jacket 37 and the cooling water passages 7d1 and 7e indicates cooling water.

  A hollow air collection space 34 is provided inside the air collection unit 15. One end of an air recovery passage 7bs is connected to the air recovery space 34. The other end of the air recovery passage 7bs is connected to a location in the engine 1 where the cooling water is likely to boil, such as in the vicinity of the cylinder head 32. The air recovery unit 15 is installed with respect to the engine 1 so that the air recovery space 34 is positioned higher than the water jacket 37. For example, the air recovery unit 15 is installed above the engine 1. By doing so, bubbles generated in the cooling water due to boiling can rise toward the air recovery space 34 along the air recovery passage 7bs as shown by the wavy arrow in FIG. The collection space 34 can collect the bubbles. That is, the air recovery device 15 can remove bubbles generated in the cooling water.

  According to the tenth embodiment described above, bubbles generated in the cooling water in the engine 1 can be removed during Cold.

[Eleventh embodiment]
Next, a cooling water control apparatus according to an eleventh embodiment of the present invention will be described. The configuration of the cooling water control apparatus 100g according to the eleventh embodiment is shown in FIG. 20, and the internal structure of the air recovery unit 15 and the engine 1 at this time is shown in FIG.

  In the cooling water control apparatus 100f according to the tenth embodiment described above, the air recovery unit 15 recovers bubbles generated in the cooling water by the air recovery space 34. However, since the air recovery device 15 recovers the bubbles as water vapor, it is difficult to suppress cooling water leakage due to an increase in pressure in the cooling water passage 7.

  Therefore, in the cooling water control apparatus 100g according to the eleventh embodiment, as shown in FIGS. 20 and 21, the bypass passage 7d2 that bypasses the engine 1 is installed so as to pass through the air recovery unit 15. To do. More specifically, the bypass passage 7d2 is installed in the air recovery unit 15 so as to pass near the air recovery space 34. Here, the solid line arrow in FIG. 21 indicates the flow of the cooling water passing through the bypass passage 7d2. In FIG. 21, hatching in the water jacket 37, the cooling water passages 7d1, 7e, and the detour passage 7d2 indicates cooling water. In FIG. 21, the cooling water that passes through the bypass passage 7d2 is cooling water that passes through the Cold cooling water route, and the water temperature is often below the boiling point. Therefore, the bubbles recovered by the air recovery space 34 are cooled and liquefied by heat exchange with the cooling water passing through the bypass passage 7d2 in the vicinity of the air recovery space 34. Thus, the air recovery device 15 according to the eleventh embodiment can cool and liquefy the bubbles recovered by the air recovery space 34 by exchanging heat with the cooling water passing through the bypass passage 7d2. Further, an increase in pressure in the cooling water passage 7 can be suppressed.

  According to the eleventh embodiment described above, an increase in pressure in the cooling water passage 7 can be suppressed during Cold, and cooling water leakage can be prevented. In addition, by performing heat exchange between the bubbles collected in the air collection space 34 and the cooling water passing through the bypass passage 7d2, the cooling water passing through the bypass passage 7d2 can be heated.

(Modification of the eleventh embodiment)
Next, a modification of the eleventh embodiment will be described. In the modification of the eleventh embodiment, in the cooling water control apparatus 100g according to the eleventh embodiment, it is detected whether or not there is a danger that the cooling water will boil, and it is detected that there is a danger that the cooling water will boil. In this case, a flow distribution three-way valve is used as the three-way valve 6, and the flow rate of the cooling water in the water jacket in the engine 1 is increased stepwise so that the flow rate of the cooling water in the bypass passage 7 d 2 that bypasses the engine 1 is increased. Decrease.

  Specifically, the ECU 20 cools the engine 1 based on the control determination items such as the fuel injection amount, the intake air amount, the throttle opening, the engine speed, the engine load, and the like based on the driving situation. Detect if water is at risk of boiling. When the ECU 20 determines that the cooling water in the engine 1 is in danger of boiling, the ECU 20 controls the three-way valve 6 (flow distribution three-way valve) to bypass the water jacket in the engine 1 and the engine 1. The distribution ratio of the flow rate of the cooling water with respect to 7d2 is adjusted, that is, the flow rate of the cooling water in each of the water jacket in the engine 1 and the bypass passage 7d2 that bypasses the engine 1 is adjusted. For example, the ECU 20 increases the flow rate of the cooling water in the water jacket in the engine 1 and bypasses the engine 1 as the value of the predetermined control determination item in the driving situation becomes closer to the threshold value at which the cooling water boils. The flow rate of the cooling water in the passage 7d2 is decreased. By doing in this way, boiling of a cooling water can be suppressed and it can suppress that a bubble arises in the cooling water in the engine 1. FIG.

  Here, as a boiling detection method for detecting the boiling of the cooling water in the engine 1, a boiling detection method for detecting the occurrence of bubbles in the cooling water, in addition to the method for detecting based on the above-described operating condition, is used. It can also be used. This detection method will be specifically described.

  FIG. 22 is a cross-sectional view showing the internal structure of the air recovery device 15 and the engine 1 according to a modification of the eleventh embodiment. As shown in FIG. 22, in the air recovery unit 15, the air recovery space 34 is formed so as to become narrower upward, and a temperature sensor 34 a that detects the temperature in the air recovery space 34 is formed at the apex thereof. Is attached. The temperature sensor 34 a supplies a detection signal corresponding to the detected temperature to the ECU 20. When the cooling water in the engine 1 boils, bubbles are generated in the cooling water. Bubbles generated in the cooling water become water vapor and rise toward the air recovery space 34 along the air recovery passage 7bs. As shown in FIG. 22, the air recovery space 34 is formed so as to become narrower upward, so that the rising water vapor reaches the temperature sensor 34a installed at the apex thereof. When water vapor reaches the temperature sensor 34a, the temperature sensor 34a indicates a temperature close to the boiling point of the cooling water.

  That is, when the temperature detected by the temperature sensor 34a becomes a temperature close to the boiling point of the cooling water, the ECU 20 indicates that the air bubbles that have reached the air recovery space 34 have reached the temperature sensor 34a. It can be determined that the cooling water in 1 is boiling. When the ECU 20 determines that the cooling water in the engine 1 is boiling in this way, the ECU 20 controls the three-way valve 6 and regards that the engine 1 has been warmed up. The cooling water is circulated through the passing hot water route or the flow distribution three-way valve is used as the three-way valve 6 to increase the flow rate of the cooling water in the water jacket in the engine 1. Even in this case, boiling of the cooling water can be suppressed.

  In addition, as described above, by using the boiling detection method using the temperature sensor 34a, the control items of the operation status (for example, fuel injection amount, intake air amount, throttle opening, engine speed, engine load, etc.) Even when the cooling water in the engine 1 has boiled due to other factors, the ECU 20 can detect the boiling of the cooling water.

  According to the modification of the eleventh embodiment described above, boiling of the cooling water in the engine 1 can be suppressed during Cold.

[Twelfth embodiment]
Next, a cooling water control apparatus according to a twelfth embodiment of the present invention will be described. The configuration of the cooling water control apparatus 100h according to the twelfth embodiment is shown in FIG.

  In the first embodiment described above, the cooling water is circulated through the Cold cooling water route that bypasses the engine 1 during Cold, and the Hot cooling water route that passes through the engine 1 is used during Hot. It was supposed to circulate cooling water. However, even when the engine 1 has been warmed up, the cooling water continues to recover the exhaust heat in the exhaust heat recovery device 2, so the cooling water may boil.

  Therefore, in the cooling water control apparatus 100h according to the twelfth embodiment, in addition to the control of the three-way valve 6 described above, as shown in FIG. 23, the cooling water circulation direction at the Hot time is set to the circulation of the cooling water at the Cold time. The direction is opposite to the direction. Specifically, unlike the cooling water control apparatus 100 according to the first embodiment, the cooling water control apparatus 100h according to the twelfth embodiment includes two electric WPs 8a and 8b. As shown in FIG. 23, the electric WPs 8a and 8b are connected in series on the cooling water passage 7b, for example. The electric WPs 8a and 8b are controlled by control signals S8a and S8b from the ECU 20, respectively. The ECU 20 circulates the cooling water in the direction of the solid line arrow shown in FIG. 23 by operating only the electric WP 8a and not operating the electric WP 8b during Cold. On the other hand, in the hot state, the ECU 20 does not operate the electric WP 8a, but operates only the electric WP 8b, thereby circulating the cooling water in the direction of the wavy arrow shown in FIG. I will let you.

  Note that the installation positions of the electric WPs 8a and 8b are not limited to those on the cooling water passage 7b. Instead, the electric WPs 8a and 8b may be installed on the cooling water passages 7a and 7f.

  24A and 24B are cross-sectional views of the exhaust heat recovery device 2. FIG. In the exhaust heat recovery device 2, a cooling water passage 22 surrounding the exhaust passage 21 and connected to the cooling water passage 7a is provided. 24A and 24B, the cooling water inlet / outlet B1 is an inlet / outlet on the heater core 5 side in FIG. 23, and the cooling water inlet / outlet B2 indicates the inlet / outlet on the thermostat 4 side in FIG. In FIGS. 24A and 24B, an arrow indicated by a one-dot chain line indicates a traveling direction of the exhaust gas.

  In FIG. 24 (a), the traveling direction of the cooling water during Cold is indicated by a solid arrow, and in FIG. 24 (b), the traveling direction of the cooling water during Hot is illustrated by a wavy arrow.

  As shown in FIG. 24A, at the time of Cold, the cooling water is set to advance in the direction opposite to the traveling direction of the exhaust gas, as indicated by the solid line arrow. Thus, when the traveling direction of the cooling water is set opposite to the traveling direction of the exhaust gas, the cooling water is compared with the case where the traveling direction of the cooling water is set in the same direction as the traveling direction of the exhaust gas. The amount of heat recovered by exhaust heat can be increased. On the other hand, as shown in FIG. 24 (b), at the time of hot, the cooling water is set to travel in the same direction as the traveling direction of the exhaust gas, as indicated by the wavy arrow. Therefore, the recovered heat quantity of the exhaust heat by the cooling water at this time is smaller than the recovered heat quantity of the cooling water at Cold.

  That is, by making the circulation direction of the cooling water at the time of Hot opposite to the circulation direction of the cooling water at the Cold time, the recovery heat amount of the cooling water at the Hot time is less than the recovery heat amount of the cooling water at the Cold time. The boiling of the cooling water at the time of hot can be suppressed.

  According to the twelfth embodiment described above, boiling of the cooling water during hot can be suppressed, and leakage of cooling water from the cooling water passage 7 and occurrence of overheating can be prevented.

(Modification of the twelfth embodiment)
Next, a modification of the twelfth embodiment will be described. The configuration of a cooling water control apparatus 100ha according to a modification of the twelfth embodiment is shown in FIG.

  In the cooling water control apparatus 100h according to the twelfth embodiment described above, the electric WPs 8a and 8b are installed in series on the cooling water passage 7 as shown in FIG. For this reason, of the electric WPs 8a and 8b, one electric WP needs to be circulated by passing the cooling water through the other electric WP that is not operated, which increases pressure loss. Further, in this case, when switching the cooling water circulation direction, the ECU 20 needs to temporarily stop both the electric WPs 8a and 8b, resulting in a control time lag.

  Therefore, in the cooling water control apparatus 100ha according to the modified example of the twelfth embodiment, as shown in FIG. 25, the electric WPs 8a and 8b are installed in parallel on the cooling water passage 7 using the three-way valve 6a. To do. Here, in the three-way valve 6a, “fa” indicates a valve on the cooling water passage side where the electric WP 8a is provided, “fb” indicates a valve on the cooling water passage side where the electric WP 8b is provided, and “fc” "Indicates a valve on the cooling water passages 7d1, 7d2.

  The ECU 20 operates the electric WP 8a and controls the three-way valve 6a to open the valves fa and fc and close the valve fb during Cold. At this time, the electric WP 8b is not operated. Thereby, cooling water can be circulated in the direction of the solid line arrow shown in FIG. On the other hand, the ECU 20 controls the three-way valve 6 at the time of Hot to switch the cooling water route to the Hot time cooling water route. At this time, the ECU 20 stops the electric WP8a, operates the electric WP8b, controls the three-way valve 6a, opens the valves fb and fc, and closes the valve fa. By doing in this way, a cooling water can be circulated in the direction of the wavy arrow shown in FIG. Thereby, boiling of the cooling water at the time of Hot can be suppressed. Further, according to the modification of the twelfth embodiment, an increase in pressure loss in the cooling water passage 7 can be suppressed, and it is not necessary to stop both the electric WPs 8a and 8b when switching the circulating direction of the cooling water. The time lag can be prevented from occurring.

  According to the modified example of the twelfth embodiment, boiling of the cooling water at the time of hot can be suppressed, and leakage of cooling water from the cooling water passage 7 and occurrence of overheating can be prevented. Further, an increase in the pressure loss of the cooling water passage 7 can be suppressed, and it is not necessary to stop both the electric WPs 8a and 8b when switching the circulating direction of the cooling water.

  Instead of installing the electric WPs 8a and 8b in parallel on the cooling water passage 7, it is assumed that the electric WP 8c capable of reversing the circulating direction of the cooling water is used alone as in the cooling system 100hb shown in FIG. Also good. The electric WP 8c is controlled by a control signal S8c from the ECU 20. In this case, the ECU 20 operates the electric WP 8c during Cold to circulate the cooling water in the direction of the solid line arrow shown in FIG. On the other hand, the ECU 20 controls the electric WP 8c at the time of hot and rotates the impeller of the electric WP 8 in the direction opposite to that at the time of Cold, thereby supplying cooling water in the direction of the wavy arrow shown in FIG. Circulate. This can also suppress an increase in pressure loss in the cooling water passage 7.

[Application example]
The cooling water control apparatus according to each of the above-described embodiments is not always limited to one that is used alone. Instead, it goes without saying that a plurality of cooling water control device configurations may be used in combination among the cooling water control device configurations according to the above-described embodiments. In addition, the cooling water route switching control method according to each of the above-described embodiments is not always limited to the method in which each is used independently. Instead, it goes without saying that a plurality of cooling water route switching control methods may be used in combination among the cooling water route switching control methods according to the above-described embodiments.

It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 1st Embodiment. It is a flowchart which shows the cooling water route switching control process which concerns on 1st Embodiment. It is a flowchart which shows the cooling water route switching control process which concerns on 2nd Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 3rd Embodiment. It is a flowchart which shows the cooling water route switching control process which concerns on 3rd Embodiment. It is a flowchart which shows the cooling water route switching control process which concerns on 4th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 5th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 5th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 6th Embodiment. It is a flowchart which shows the cooling water route switching control process which concerns on 6th Embodiment. It is a flowchart which shows the cooling water route switching control process which concerns on 7th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 8th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 8th Embodiment. It is a flowchart which shows a heater blower air volume control process. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 9th Embodiment. It is a graph which shows the change with respect to time of the temperature of cooling water. It is a flowchart which shows the cooling water route switching control process which concerns on 9th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 10th Embodiment. It is sectional drawing which shows the internal structure of the air recovery device and engine which concern on 10th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 11th Embodiment. It is sectional drawing which shows the internal structure of the air recovery device and engine which concern on 11th Embodiment. It is sectional drawing which shows the internal structure of the air recovery device and engine which concern on the modification of 11th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on 12th Embodiment. It is sectional drawing of an exhaust heat recovery device. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on the modification of 12th Embodiment. It is a figure which shows schematic structure of the cooling water control apparatus which concerns on the modification of 12th Embodiment.

Explanation of symbols

1 engine (internal combustion engine)
2 Exhaust heat recovery device 3 Radiator 4 Thermostat 5 Heater core 6 Three-way valve 8 Electric water pump (electric WP)
20 ECU

Claims (13)

A cooling water control device for an internal combustion engine having a cooling water passage that circulates between the internal combustion engine, an exhaust heat recovery device, and a heater core,
A bypass passage connected to the cooling water passage and bypassing the internal combustion engine;
Flow rate distribution means for distributing the flow rate of cooling water between the water jacket in the internal combustion engine and the bypass passage;
Control means for controlling the flow rate distribution means,
The control means changes the ratio of the flow rate of the cooling water in the water jacket in the internal combustion engine and the flow rate of the cooling water in the bypass passage by using the flow rate distribution means when the internal combustion engine is warmed up. An internal combustion engine cooling water control device.   When the internal combustion engine is warmed up, the control means has a case where the required heat amount of the heater core is larger than the recovered heat amount recovered by the exhaust heat recovery device, and the cooling water in the water jacket in the internal combustion engine The cooling water control device for an internal combustion engine according to claim 1, wherein when the water temperature is higher than the required temperature, the flow rate of the cooling water in the water jacket in the internal combustion engine is increased.   The cooling water control device for an internal combustion engine according to claim 2, wherein the required heat amount is a required heat amount according to at least one of a heating request, a defroster request, and a deice request.   When the control means determines that the temperature of the cooling water flowing through the exhaust heat recovery device is higher than the temperature of the cooling water in the water jacket in the internal combustion engine, the control means in the water jacket in the internal combustion engine The cooling water control device for an internal combustion engine according to claim 1, wherein the flow rate of the cooling water is increased.   2. The cooling water control device for an internal combustion engine according to claim 1, wherein the flow rate distribution unit is a three-way valve and has an intermediate temperature mode in which the cooling water in the water jacket in the internal combustion engine and the cooling water in the bypass passage are mixed. .   The cooling water control device for an internal combustion engine according to claim 1, wherein the heater core is provided in a cooling water passage on a downstream side of the exhaust heat recovery device.   The cooling water control for an internal combustion engine according to claim 2, wherein the control means determines whether a required heat amount of the heater core is larger than a recovered heat amount recovered by the exhaust heat recovery device based on an intake air amount. apparatus.   The control means prohibits an increase in the flow rate of cooling water in a water jacket in the internal combustion engine when an integrated amount of the intake air amount in a predetermined time is larger than a predetermined amount. A cooling water control device for an internal combustion engine according to claim 1. Based on the integrated value of the intake air amount and the integrated value of the heater blower air volume, the heater core inlet water temperature estimating means for estimating the water temperature in the vicinity of the inlet through which the cooling water flows in the heater core,
2. The cooling water control device for an internal combustion engine according to claim 1, wherein the control unit controls a heater blower air volume of the heater core based on a cooling water temperature estimated by the heater core inlet water temperature estimation unit. A heater core inlet water temperature detecting means for detecting a coolant temperature near the inlet flowing into the heater core;
When the water temperature detected by the heater core inlet water temperature detecting means is lower than a predetermined temperature after the warm-up is completed, the control means increases the flow rate of the cooling water in the bypass passage, and the water temperature in the internal combustion engine is increased. The cooling water control device for an internal combustion engine according to claim 1, wherein the flow rate of the cooling water in the jacket is reduced.   The cooling water control device for an internal combustion engine according to claim 1, further comprising bubble liquefaction means for liquefying bubbles generated in the cooling water in the internal combustion engine by performing heat exchange with the cooling water passing through the bypass passage. Comprising bubble detecting means for detecting bubbles generated in the cooling water in the internal combustion engine,
12. The cooling water control device for an internal combustion engine according to claim 11, wherein the control means increases the flow rate of the cooling water in a water jacket in the internal combustion engine when bubbles are detected by the bubble detection means.   2. The cooling of the internal combustion engine according to claim 1, wherein the control means makes the circulation direction of the cooling water after the warming-up of the internal combustion engine is opposite to the circulation direction of the cooling water when the internal combustion engine is warmed up. Water control device.

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