JP2010121456A - Engine cooling system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine cooling system improving the warm-up performance of an internal combustion engine and appropriately controlling the circulation of cooling water to each heat exchanger as required. <P>SOLUTION: The cooling system of an engine 1, after passing a cooling medium through a cooling passage in the engine and then passing it through a radiator passage 200 with a radiator 3 fitted therein, returns the cooling medium to the cooling passage in the engine. In this case, at least one passage is arranged to which part of the cooling medium is guided and which passes the cooling medium through an auxiliary heat exchanger fitted therein and then returns the cooling medium to the cooling passage in the engine. A passage having one end connected to the radiator and the other end connected to the auxiliary heat exchanger is provided. A thermostat including a valve element driven by a thermally-actuated element thermally actuated in accordance with the temperature of the cooling medium controls the flow of the cooling medium to the radiator and also controls, as required, switching between the passage which passes the cooling medium through the auxiliary heat exchanger and then returns the cooling medium to the cooling passage in the engine and the passage connected to the auxiliary heat exchanger. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a cooling system for circulating an engine coolant.

As this type of cooling system, for example, Patent Document 1 discloses an engine coolant circuit that can shorten the warm-up time and sufficiently cool an EGR (Exhaust Gas Recirculation) cooler after the warm-up is completed. Is described.
As shown in FIG. 14, the engine coolant circuit described in Patent Document 1 includes a first electromagnetic valve 27 and a second electromagnetic valve in addition to the thermostat 10 and the water pump 11 provided in a normal internal combustion engine. 28, a plurality of electromagnetic valves such as the third electromagnetic valve 29 and the electric pump 35, and a control means 31 for electrically controlling them, a water temperature detecting means 30 for detecting the engine outlet water temperature, and the like. Yes.
JP 2007-263034 A

  However, as described above, Patent Document 1 discloses a plurality of electromagnetic valves 26 to 29 and an electric pump in addition to a thermostat 10 and a water pump 11 provided in a cooling water circuit of a normal internal combustion engine (engine). 35, the control means 31, the water temperature detection means 30, and the like are required, so that there is a situation that the product cost increases.

  In addition, since the plurality of components are arranged in the cooling water circuit as described above and the cooling water circuit is also a complicated circuit, the entire system becomes larger and more complicated, making it difficult to reduce the size and weight. In addition, there is a situation in which the restriction on the degree of freedom of the layout mounted on the vehicle becomes large.

  Furthermore, the control is performed not only for switching the cooling water passage through which the cooling water flows by the opening / closing operation of the electromagnetic valves 27 to 29 and the on / off operation of the electric pump 35, but also for the switching water such as the opening / closing operation and the on / off operation. There is a situation that consideration is not given to performing continuous flow control of the cooling water flowing through the passage.

  Further, the one described in Patent Document 1 is a control / operation form specialized when an EGR cooler is used as a heat exchanger, and is not very diverse. For example, an ATF (Automatic Transmission Fluid) cooler, an oil cooler, an intercooler, etc. When it is going to apply to other heat exchangers, such as a cooler, or a cooling water system provided with a plurality of heat exchangers, there is a situation where it is difficult to adopt.

  The present invention has been made in view of such circumstances, and is capable of improving the warm-up performance of the internal combustion engine while having a small, lightweight, simple and inexpensive configuration, and cooling water to each heat exchanger. It is an object of the present invention to provide a cooling system for an engine (internal combustion engine) whose distribution can be appropriately controlled according to demand.

For this reason, the engine cooling system according to the present invention is:
An engine cooling system for returning a cooling medium to a cooling passage in the engine again after passing through a cooling passage in the engine and a radiator passage in which a radiator is interposed,
After a part of the cooling medium is guided and passed through an auxiliary heat exchanger for interposing, at least one passage for returning the cooling medium to the cooling passage in the engine is disposed,
One end is connected to the radiator, and the other end is connected to the auxiliary heat exchanger.
A thermostat configured to include a valve body driven by a thermally responsive element that is thermally responsive to the temperature of the cooling medium,
Controlling the inflow of the cooling medium to the radiator,
After passing through the auxiliary heat exchanger, a passage for returning the cooling medium to a cooling passage in the engine, the one end connected to the radiator, and the other end connected to the auxiliary heat exchanger The passage is controlled to be switched according to demand.

  In the present invention, in the passage where the one end is connected to the radiator and the other end is connected to the auxiliary heat exchanger, one end is connected downstream from the radiator and the other end is connected upstream from the heat exchanger. It can be characterized by that.

  In the present invention, in the passage where the one end is connected to the radiator and the other end is connected to the auxiliary heat exchanger, one end is connected to the upstream side of the radiator and the other end is connected to the downstream side of the heat exchanger. It can be characterized by that.

  According to the present invention, the warm-up performance of the internal combustion engine can be improved while being small, light, simple and inexpensive, and the flow of the cooling water to each heat exchanger is appropriately controlled according to demand. An engine cooling system can be provided.

  Embodiments of an engine (internal combustion engine) cooling system according to the present invention will be described below in detail with reference to the accompanying drawings. The present invention is not limited to the examples described below.

  As shown in FIG. 1, the cooling water system for an internal combustion engine 1 according to the first embodiment of the present invention is installed in, for example, an automobile or used in a stationary engine 1 (gasoline, light oil, alcohol, etc.). In addition, the present invention is applied to a cooling system such as a cooling circuit for a combustion apparatus that does not extract power and a cell cooling circuit for a fuel cell, in addition to a heat engine such as an internal combustion engine or an external combustion engine that uses various miscellaneous fuels. Is possible).

  As shown in FIG. 1, a mechanically driven water pump 2 driven by a crankshaft or the like is connected to an inlet side of a cooling passage (not shown) inside the engine 1. A thermostat 100 is disposed on the outlet side of the cooling passage, and a radiator passage that is connected to the water pump 2 with a radiator 3 that is a heat exchanger for radiating the cooling water of the engine 1 interposed in the thermostat 100. 200 is connected, and a heater core passage 300 connected to the water pump 2 through which the heater core 4 as a heat exchanger for the heater system is interposed is connected.

The thermostat 100 is connected to a bypass passage 400 that bypasses the radiator 3 and is connected to the water pump 2.
Further, in the present embodiment, an EGR cooler passage 500 connected to the water pump 2 is connected to the outlet side of the cooling passage inside the engine 1, which is connected to the water pump 2 with the EGR cooler 5 being a heat exchanger for cooling EGR gas. In addition, the EGR cooler passage 500 is connected to an oil cooler passage 600 that is connected to the water pump 2 with an oil cooler 6 that is a heat exchanger for cooling engine oil, transmission oil, and the like interposed therebetween.

  In addition, in the present embodiment, a branch passage 210 that is branched after passing through the radiator passage 200 is disposed, and the branch passage 210 includes a passage 510 that is connected to the upstream side of the cooling water flow of the EGR cooler 5; It is branched into a passage 610 connected to the upstream side of the cooling water flow of the oil cooler 6.

  Here, the thermostat 100 used in the present embodiment has the same configuration as that of a conventional thermostat. For example, as shown in FIG. 4, the temperature sensing unit 181 side of the thermo element 180 (thermally responsive element) is accommodated therein. The housing portion 101 is provided. Further, a support portion 102 that supports the piston rod 181a of the thermo element 180 and a radiator side connection portion 120 to which the radiator passage 200 is connected are provided.

  The housing portion 101 includes an engine side connection portion 110 connected to the outlet side of the water pump 2 (that is, the outlet side of the cooling passage inside the engine 1), and a heater core passage connection portion connected to the heater core passage 300. 130 and a bypass passage connecting portion 140 connected to the bypass passage 400 is provided.

  Here, the thermo element 180 includes a temperature sensing unit 181 that encloses a thermal expansion body such as wax that expands and contracts by sensing the temperature of the cooling water in the housing unit 101, and the temperature sensing unit 181 receives the temperature from the temperature sensing unit 181. A piston rod 181a that expands and contracts along the vertical direction in FIG. 2 in accordance with the thermal expansion and contraction of the thermal expansion body inside the sensing unit 181 protrudes.

  One end (upper end in FIG. 2) of the piston rod 181a is supported by the support portion 102, and the other end is accommodated in the temperature sensing portion 181.

  A spring seat 182 is attached to the temperature sensing portion 181 substantially integrally with the temperature sensing portion 181 on the piston rod 181 a side. The spring seat 182 is connected to the radiator side connecting portion 120 side and the housing portion 101. It is configured to have a valve shape that can function as a valve that communicates or blocks the inside.

  Further, a spring seat 103 that is substantially integral with the housing portion 101 (the support portion 102) is provided to face the spring seat 182. Between the spring seat 103 and the spring seat 182, the spring seat 103 is provided. A coil spring 185 that biases the seat 182 toward the valve closing side (upward in FIG. 2) is disposed.

  A rod 183 extends on the lower side in FIG. 2 at the lower end of the temperature sensing unit 181 of the thermostat 100 according to the present embodiment.

  A spring seat 184 is attached to the lower end of the rod 183. The spring seat 184 is slidably inserted into the rod 183 and is controlled to move downward via a position restricting member 189 such as a snap ring disposed at the lower end of the rod 183, for example. The position restricting member 189 is biased by a spring 187.

  The spring seat 184 has a valve shape capable of functioning as a valve for communicating or blocking the bypass passage connecting portion 140 and the interior of the housing portion 101.

  The operation of the thermostat 100 according to this embodiment having the above-described configuration will be described below.

(Bypass circulation state: Fig. 1 and Fig. 4)
1 and 4 show a state from engine start to warm-up, in which the coolant temperature is low and the temperature sensing unit 181 is in the initial position, as shown in FIG. Is closed and the spring seat 184 is opened.

Therefore, the cooling water fed by the water pump 2 is guided into the housing 101 of the thermostat 100 from the engine side connecting part 110 connected to the outlet side of the cooling passage inside the engine 1, as shown in FIG. It flows through the thermostat 100 and is returned to the water pump 2 through the heater core passage 300 and the bypass passage 400 as shown in FIG.
Thereby, the amount of heat taken away from the cooling water to the outside is reduced, and warming up of the engine 1 is promoted.
As shown in FIG. 1, the EGR cooler passage 500 connected to the outlet side of the cooling passage inside the engine 1 without passing through the thermostat 100 has cooling water that has passed through the cooling passage inside the engine 1. Is circulated through the EGR cooler passage 500 and the oil cooler passage 600.

(Temperature adjustment state (end of warm-up to temperature control): FIGS. 2 and 5)
When the coolant temperature rises to a predetermined level in response to the heat of the engine 1 from the bypass circulation state of FIGS. 1 and 4, the thermal expansion body in the temperature sensing unit 181 of the thermo element 180 is thermally expanded to extend the piston rod 181a. Therefore, as shown in FIG. 5, the spring seat 182 is moved downward in FIG. 5 against the urging force of the coil spring 185 to open the valve, and the radiator side connecting portion 120 extends to the radiator passage. 200 communicates with the inside of the housing portion 101.

  Further, as shown in FIG. 5, the spring seat 184 is pushed downward by the rod 183 in FIG. 5, but is kept open, and the valve opening amount (the bypass passage connecting portion 140 shown in FIG. 5) is maintained. The distance from the middle upper end surface (valve seat) is reduced by the amount of movement of the rod 183 downward in FIG.

  As a result, as shown in FIG. 5, the cooling water fed by the water pump 2 flows into the radiator side connecting portion 120 and the radiator passage 200, and as shown in FIG. The water is returned to the water pump 2 through the radiator passage 200, the heater core passage 300, the bypass passage 400, the EGR cooler passage 500, and the oil cooler passage 600.

For this reason, the cooling water of the engine 1 can be cooled by the radiator 3 interposed in the radiator passage 200.
Further, since the cooling water also flows into the branch passage 210 branched from the radiator passage 200, the cooling water flows into the passage 510 and the passage 610 connected to the branch passage 210. Therefore, since a part of the relatively low-temperature cooling water that has passed through the radiator 3 and is cooled can be guided to the EGR cooler 5 and the oil cooler 6, the EGR gas and oil can be effectively cooled. .

  When the spring seat 182 is opened as in this state, the thermal expansion body in the temperature sensing unit 181 of the thermo element 180 is thermally expanded or contracted according to the temperature change of the cooling water, and the piston rod 181a is expanded or contracted. As a result, the degree of communication between the radiator-side connecting portion 120 and the radiator passage 200 and the inside of the housing portion 101 (that is, the valve opening amount of the spring seat 182) is adjusted. The amount of heat released from the cooling water is controlled, so that the temperature of the cooling water can be controlled to a predetermined temperature.

  Further, the cooling water flowing through the branch passage 210 (and thus the passages 510 and 610), the EGR passage 500, and the oil cooler passage 600 is controlled, so that the temperature state of the engine 1 by the radiator 3 and the EGR gas by the EGR cooler 5 are controlled. The temperature state and the temperature state of the engine oil, transmission oil, etc. by the oil cooler 6 can be suitably controlled as required.

(Bypass valve closed state (at high water temperature): Fig. 3 and Fig. 6)
When the temperature of the cooling water further rises from the above temperature adjustment state, the thermal expansion body in the temperature sensing unit 181 of the thermo element 180 further expands, and the piston rod 181a is extended, as shown in FIG. The spring seat 184 attached to the rod 183 moves downward in FIG. 6 while maintaining the open state of the spring seat 182 so that the bypass passage side connecting portion 140 extends to the bypass passage 400 and the A closed valve state is established in which communication with the interior of the housing portion 101 is blocked.

  That is, when the spring seat 184 is closed in this way, as shown in FIG. 3, the cooling water fed by the water pump 2 extends to the bypass passage side connecting portion 140 and to the bypass passage 400. And is returned to the water pump 2 through the radiator passage 200, the branch passage 210 (and thus the passages 510 and 610), the heater core passage 300, the EGR cooler passage 500, and the oil cooler passage 600. become.

  For this reason, since the flow volume of the cooling water which passes the radiator 3 interposed by the said radiator channel | path 200 can be increased more, it suppresses effectively that the cooling water of the engine 1 becomes high temperature more than predetermined. It becomes possible. In addition, since a part of the relatively low-temperature cooling water that has passed through the radiator 3 and is cooled can be guided to the EGR cooler 5 and the oil cooler 6, the EGR gas and oil can be effectively cooled. Become.

  As described above, according to the cooling system of the present embodiment, even when a plurality of heat exchangers 3, 4, 5, 6 and the like are provided, the engine 1 is warmed up with a small, lightweight, simple and inexpensive configuration. The performance can be improved and the flow of the cooling water to each of the heat exchangers 3, 4, 5, 6 can be appropriately controlled according to the request.

Next, a second embodiment according to the present invention will be described.
The second embodiment is an example in which the thermostat 100 is disposed on the suction side of the water pump 2 (the inlet side of the cooling passage inside the engine 1) as shown in FIGS. Is shown. In addition, the same code | symbol is attached | subjected to the element similar to the element demonstrated in Example 1, and detailed description is abbreviate | omitted.

  The operation of the thermostat 100 according to the present embodiment will be described below.

(Bypass circulation state: FIGS. 7 and 10)
7 and 10 show a state from engine start to warm-up. The spring seat 182 is closed and the spring seat 184 is closed in a state where the coolant temperature is low and the temperature sensing unit 181 is in the initial position. Is open.

Therefore, the cooling water fed by the water pump 2 and passing through the cooling passage inside the engine 1 flows into the thermostat 100 from the heater core passage 300 and the bypass passage 400, and flows through the thermostat 100 as shown in FIG. It passes through the engine side connection part 110 connected to the inlet side of the cooling passage inside the engine 1 and is returned to the water pump 2 as shown in FIG.
Thereby, the amount of heat taken away from the cooling water to the outside is reduced, and warming up of the engine 1 is promoted.

  As shown in FIG. 7, the EGR cooler passage 500 connected to the outlet side of the cooling passage inside the engine 1 without passing through the thermostat 100 has cooling water that has passed through the cooling passage inside the engine 1. Is circulated through the EGR cooler passage 500 and the oil cooler passage 600.

(Temperature adjustment state (end of warm-up to temperature control operation): FIGS. 8 and 11)
When the coolant temperature rises to a predetermined level in response to the heat of the engine 1 from the bypass circulation state of FIGS. 7 and 10, the thermal expansion body in the temperature sensing unit 181 of the thermo element 180 is thermally expanded to extend the piston rod 181a. Therefore, as shown in FIG. 8, the spring seat 182 is moved downward in FIG. 8 against the urging force of the coil spring 185 and opened, and the radiator side connecting portion 120 extends to the radiator passage. 200 communicates with the inside of the housing portion 101.

  Further, as shown in FIG. 8, the spring seat 184 is pushed down by the rod 183 in FIG. 8 but is kept open, and the valve opening amount (see FIG. 8 of the bypass passage connecting portion 140). The distance from the middle upper end surface (valve seat) is reduced by the amount of movement of the rod 183 downward in FIG.

As a result, as shown in FIG. 8, the cooling water fed by the water pump 2 and passing through the cooling passage inside the engine 1 flows into the thermostat 100 from the radiator passage 200, the heater core passage 300, and the bypass passage 400, As shown in FIG. 11, it flows in the thermostat 100, passes through the engine side connection part 110 connected to the inlet side of the cooling passage inside the engine 1, and is returned to the water pump 2 as shown in FIG. It will be.
For this reason, the cooling water of the engine 1 can be cooled by the radiator 3 interposed in the radiator passage 200.
In addition, when the spring seat 182 is opened, cooling water is allowed to enter the branch passage 210 connected to the radiator passage 200 from the engine 1. As shown in FIG. 8, the cooling water flows from the passage 510 and the passage 610 connected thereto. Therefore, a part of the relatively high-temperature cooling water that has passed through the EGR cooler 5 and the oil cooler 6 can be effectively cooled by passing through the radiator 3.

  When the spring seat 182 is opened as in this state, the thermal expansion body in the temperature sensing unit 181 of the thermo element 180 is thermally expanded or contracted according to the temperature change of the cooling water, and the piston rod 181a is expanded or contracted. As a result, the degree of communication between the radiator-side connecting portion 120 and the radiator passage 200 and the inside of the housing portion 101 (that is, the valve opening amount of the spring seat 182) is adjusted. The amount of heat released from the cooling water is controlled, so that the temperature of the cooling water can be controlled to a predetermined temperature.

  Further, the cooling water flowing through the branch passage 210 (and thus the passages 510 and 610), the EGR passage 500, and the oil cooler passage 600 is controlled, so that the temperature state of the engine 1 by the radiator 3 and the EGR gas by the EGR cooler 5 are controlled. The temperature state and the temperature state of the engine oil, transmission oil, etc. by the oil cooler 6 can be suitably controlled as required.

(Bypass valve closed state (at high water temperature): FIGS. 9 and 12)
When the temperature of the cooling water further rises from the above temperature adjustment state, the thermal expansion body in the temperature sensing unit 181 of the thermo element 180 further expands, and the piston rod 181a is extended, as shown in FIG. While the valve seat of the spring seat 182 is maintained, the spring seat 184 attached to the rod 183 moves downward in FIG. 12 to extend the bypass passage side connecting portion 140 and the bypass passage 400 and the A closed valve state is established in which communication with the interior of the housing portion 101 is blocked.

  That is, when the spring seat 184 is closed in this way, as shown in FIG. 9, the cooling water fed by the water pump 2 and passing through the cooling passage inside the engine 1 is transferred to the bypass passage side connecting portion. 140, the flow into the bypass passage 400 is blocked, and the radiator passage 200, the branch passage 210 (and the passages 510 and 610), the heater core passage 300, the EGR cooler passage 500, and the oil cooler passage 600 are separated. Through the water pump 2.

  For this reason, since the flow volume of the cooling water which passes the radiator 3 interposed by the said radiator channel | path 200 can be increased more, it suppresses effectively that the cooling water of the engine 1 becomes high temperature more than predetermined. It becomes possible. Further, a part of the relatively high-temperature cooling water that has passed through the EGR cooler 5 and the oil cooler 6 can be passed through the radiator 3 to be effectively cooled.

  As described above, according to the cooling system of the present embodiment, even when a plurality of heat exchangers 3, 4, 5, 6 and the like are provided, the engine 1 is warmed up with a small, lightweight, simple and inexpensive configuration. The performance can be improved and the flow of the cooling water to each of the heat exchangers 3, 4, 5, 6 can be appropriately controlled according to the request.

Next, a third embodiment according to the present invention will be described.
In the third embodiment, as shown in FIG. 13, the upstream end of the EGR cooler passage 500 and the upstream end of the oil cooler passage 600 are connected to the bypass passage 400 connected to the thermostat 100 as compared to the first embodiment. Are connected. In addition, the same code | symbol is attached | subjected to the element similar to the element demonstrated in Example 1, and detailed description is abbreviate | omitted.

  As in the cooling system having such a configuration, the EGR cooler passage 500 in which the EGR cooler 5 is interposed, the oil cooler passage 600 in which the oil cooler 6 is interposed, and the bypass passage 400 are mutually connected (communication). In this case, when the bypass valve (spring seat 184) shown in FIG. 6 is closed, the auxiliary cooling passages (here, the EGR cooler passage 500 and the oil cooler passage 600) return the cooling water to the cooling passage in the engine 1. Since the flow of the cooling water flowing through the radiator 3 can be restricted (blocked) and the flow rate of the cooling water passing through the radiator 3 can be increased, the cooling water of the engine 1 becomes higher than a predetermined temperature. Can be effectively suppressed.

  In addition, since a part of the relatively low-temperature cooling water that has passed through the radiator 3 and is cooled can be guided to the EGR cooler 5 and the oil cooler 6 through the branch passage 210 and the passages 510 and 610, The EGR gas and oil can be cooled more effectively.

  When the thermostat 100 as shown in the second embodiment is disposed on the inlet side of the engine 1, the bypass passage 400 connected to the thermostat 100, the downstream end of the EGR cooler passage 500, and the oil cooler passage In this case, the flow rate of the cooling water passing through the radiator 3 can be further increased when the bypass valve (spring seat 184) is closed. It becomes possible to effectively suppress the cooling water of the engine 1 from becoming higher than a predetermined temperature.

  Further, in such a case, when the thermostat 100 is disposed on the outlet side of the engine 1 (example in FIG. 13), the cooling that is cooled by passing through the radiator 3 to the heat exchanger (EGR cooler 5, oil cooler 6). In contrast to supplying water, the cooling water heated by the heat exchanger (EGR cooler 5, oil cooler 6) is cooled by the radiator 3, so the heat exchanger (EGR cooler 5, oil cooler 6) There is an advantage that the heat that has been returned to the engine 1 through the radiator 3 can be further dissipated by the radiator 3.

  By the way, not limited to the above, the upstream end portion of the EGR cooler passage 500 (the downstream end portion when the thermostat 100 is disposed on the inlet side of the engine 1) or the upstream end portion (the thermostat 100 of the oil cooler passage 600). One of the downstream end portions when connected to the inlet side of the engine 1 is connected to the bypass passage 400 and the other is shown in FIG. 1 (FIG. 7 when the thermostat 100 is disposed on the inlet side of the engine 1). As described above, it may be configured to be connected to the cooling passage in the engine 1.

  Therefore, even in the cooling system according to the present embodiment, even when a plurality of heat exchangers 3, 4, 5, 6 and the like are provided, the warm-up performance of the engine 1 is improved with a small, lightweight, simple and inexpensive configuration. In addition, it is possible to appropriately control the flow of the cooling water to the heat exchangers 3, 4, 5, and 6 as required.

  Incidentally, in each of the above-described embodiments, the EGR cooler passage 500 and the oil cooler passage 600 can be replaced with each other, and another passage (for example, a torque converter or torque converter oil is cooled as required). For example, a passage of cooling water supplied to the heat exchanger for cooling, a passage of cooling water supplied to the intercooler for cooling the supply air, and the like.

  In each embodiment, the case where the heater core 4 and the heater core passage 400 are connected has been described. However, the heater system can be controlled by an independent control system, and thus the heater core 4 and the heater core passage 400 are not connected. The present invention is applicable also to cases.

  Further, in each of the above-described embodiments, the temperature sensing unit 181 that encloses a thermal expansion body such as wax of the thermo element 180 that is a thermally responsive element senses the temperature of the cooling water in the housing unit 101 (predetermined region). However, the present invention is not limited to this, and a thermal expansion body such as wax of the thermo element 180 is enclosed so that the desired temperature of the cooling water to be controlled can be sensed. The temperature sensing unit 181 may be configured to be disposed at a site different from the inside of the housing unit 101 (predetermined region).

  In addition, this invention is not limited to the structure demonstrated by each Example mentioned above, It cannot be overemphasized that the shape of each part which comprises the thermostat 100, a structure, etc. can be deform | transformed and changed suitably.

  In addition, the actuator of the thermally responsive valve is not limited to a thermo element enclosing a thermal expansion body such as wax that senses and expands and contracts by detecting the temperature described in each of the above-described embodiments, but may be a temperature such as a bimetal or a shape memory alloy. A member using a member that deforms accordingly can also be used.

  Moreover, each thermostat which concerns on each Example mentioned above may be arrange | positioned in the engine cooling water circuit at the entrance side of the engine 1, or may be arrange | positioned at the exit side.

  Furthermore, the thermostat (thermally responsive valve) device according to the present invention is not limited to the case where it is applied to a cooling system for an internal combustion engine, but is used for cooling a fuel cell vehicle such as a vehicle, equipment, or the like that requires refrigerant distribution. It can also be applied to devices, other cooling devices that require warm-up, and liquid lines.

  The embodiment described above is merely an example for explaining the present invention, and various modifications can be made without departing from the gist of the present invention.

1 is an overall configuration diagram schematically showing an example of a cooling water system (bypass circulation state: during warm-up) of an internal combustion engine according to a first embodiment of the present invention. It is a whole block diagram which shows roughly an example of the cooling water system (temperature adjustment state (warming-up completion-temperature control operation | movement)) of the internal combustion engine which concerns on an Example same as the above. It is a whole block diagram which shows roughly an example of the cooling water system (bypass valve closing state (at the time of high water temperature)) of the internal combustion engine which concerns on an Example same as the above. It is a schematic sectional drawing explaining the operation state of the thermostat (bypass circulation state: during warming-up) which concerns on an Example same as the above. It is a schematic sectional drawing explaining the operation state of the thermostat (temperature adjustment state (warming-up completion-temperature control operation | movement)) which concerns on an Example same as the above. It is a schematic sectional drawing explaining the operation state of the thermostat (bypass valve closed state (at the time of high water temperature)) which concerns on an Example same as the above. It is a whole block diagram which shows roughly an example of the cooling water system (bypass circulation state: during warming-up) of the internal combustion engine which concerns on Example 2 of this invention. It is a whole block diagram which shows roughly an example of the cooling water system (temperature adjustment state (warming-up completion-temperature control operation | movement)) of the internal combustion engine which concerns on an Example same as the above. It is a whole block diagram which shows roughly an example of the cooling water system (bypass valve closing state (at the time of high water temperature)) of the internal combustion engine which concerns on an Example same as the above. It is a schematic sectional drawing explaining the operation state of the thermostat (bypass circulation state: during warming-up) which concerns on an Example same as the above. It is a schematic sectional drawing explaining the operation state of the thermostat (temperature adjustment state (warming-up completion-temperature control operation | movement)) which concerns on an Example same as the above. It is a schematic sectional drawing explaining the operation state of the thermostat (bypass valve closed state (at the time of high water temperature)) which concerns on an Example same as the above. It is a whole block diagram which shows roughly an example of the cooling water system of the internal combustion engine which concerns on Example 3 of this invention. It is a whole block diagram which shows roughly an example of the cooling water circuit (cooling water system) of the conventional internal combustion engine.

Explanation of symbols

1 Internal combustion engine
2 Water pump 3 Radiator 4 Heater core (an example of an auxiliary heat exchanger according to the present invention)
5 EGR cooler (an example of an auxiliary heat exchanger according to the present invention)
6 Oil cooler (an example of an auxiliary heat exchanger according to the present invention)
8 Electric Water Pump 100 Thermostat 200 Radiator Passage 210, 510, 510 Branch Passage 300 Heater Core Passage (Example of Cooling Passage for Auxiliary Equipment according to the Present Invention)
400 Bypass passage 500 EGR cooler passage (an example of a cooling passage for auxiliary equipment according to the present invention)
600 Oil cooler passage (an example of a cooling passage for auxiliary equipment according to the present invention)

Claims (3)

An engine cooling system for returning a cooling medium to the cooling passage in the engine again after passing through the cooling passage in the engine and the radiator passage in which the radiator is interposed,
After a part of the cooling medium is guided and passed through an auxiliary heat exchanger for interposing, at least one passage for returning the cooling medium to the cooling passage in the engine is disposed,
One end is connected to the radiator, and the other end is connected to the auxiliary heat exchanger.
A thermostat configured to include a valve body driven by a thermally responsive element that is thermally responsive to the temperature of the cooling medium,
Controlling the inflow of the cooling medium to the radiator,
After passing through the auxiliary heat exchanger, a passage for returning the cooling medium to a cooling passage in the engine, the one end connected to the radiator, and the other end connected to the auxiliary heat exchanger An engine cooling system characterized in that the passage is switched and controlled as required.   In the passage in which the one end is connected to the radiator and the other end is connected to the auxiliary heat exchanger, one end is connected to the downstream side of the radiator and the other end is connected to the upstream side of the heat exchanger. The engine cooling system according to claim 1.   In the passage where the one end is connected to the radiator and the other end is connected to the auxiliary heat exchanger, one end is connected to the upstream side of the radiator and the other end is connected to the downstream side of the heat exchanger. The engine cooling system according to claim 1.

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