JP6152826B2 - Cooling device for internal combustion engine - Google Patents

Description

  The present invention relates to a cooling device for an internal combustion engine.

  As a conventional cooling device for an internal combustion engine, Patent Document 1 discloses that a refrigerant path through which a refrigerant that has passed through the internal combustion engine passes through a heater, a refrigerant path through which the refrigerant that has passed through the internal combustion engine passes through a radiator, and the internal combustion engine have passed. A cooling device is disclosed that includes a refrigerant path through which refrigerant passes through a transmission. Further, in the cooling device according to Patent Document 1, when the oil temperature of the transmission is a high temperature equal to or higher than a predetermined value, the flow rate of the refrigerant passing through the heater is decreased while increasing the flow rate of the refrigerant passing through the transmission.

JP 2006-125274 A

  According to the cooling device according to Patent Literature 1, as described above, when the oil temperature of the transmission is high, an increase in the temperature of the oil temperature of the transmission can be suppressed by increasing the flow rate of the refrigerant passing through the transmission. . However, in the cooling device according to Patent Document 1, in this case, the flow rate of the refrigerant passing through the heater is decreased, and thus the heater performance may be deteriorated.

  An object of the present invention is to provide a cooling device for an internal combustion engine capable of achieving both of ensuring of heater performance and suppression of increase in oil temperature of a transmission.

  A cooling device for an internal combustion engine according to the present invention includes a transmission path through which a post-passage refrigerant that has passed through the internal combustion engine passes through a transmission of a vehicle, and a heater through which the post-passage refrigerant passes through a heater that air-conditions the interior of the vehicle. A path, a radiator path through which the post-passage refrigerant passes through the radiator of the vehicle, a first state in which the post-passage refrigerant passes through the transmission path, the heater path and the radiator path, and the post-passage refrigerant through the heater. A refrigerant path switching device capable of switching between the transmission path and the second state passing through the radiator path without passing through the path, and the oil temperature of the transmission is equal to or higher than a predetermined value and there is an output request of the heater The first state based on the indoor temperature and the indoor set temperature. As the serial and the second state is switched, and a, a control device for controlling the refrigerant passage switching device.

  According to the cooling apparatus for an internal combustion engine according to the present invention, when the oil temperature of the transmission is equal to or higher than a predetermined value and the output of the heater is requested, the first state and the first state are determined based on the indoor temperature and the indoor set temperature. Two states can be switched. Thereby, it is possible to achieve both of ensuring the heater performance and suppressing the increase in the oil temperature of the transmission.

  ADVANTAGE OF THE INVENTION According to this invention, the cooling device of the internal combustion engine which can aim at coexistence with ensuring of heater performance and suppression of the oil temperature rise of a transmission can be provided.

FIG. 1 is a schematic diagram showing the overall configuration of a vehicle equipped with a cooling device for an internal combustion engine. FIG. 2 is a schematic diagram for explaining details of the operation of the refrigerant path switching device. FIG. 3 is a diagram illustrating an example of a flowchart executed when the control device switches between the first state and the second state. FIGS. 4A to 4E are diagrams illustrating examples of timing charts when the control device switches between the first state and the second state.

  Hereinafter, modes for carrying out the present invention will be described.

  An internal combustion engine cooling device 50 according to an embodiment of the present invention will be described. The cooling device 50 according to the present embodiment is mounted on the vehicle 5. FIG. 1 is a schematic diagram showing an overall configuration of a vehicle 5 on which a cooling device 50 is mounted. The vehicle 5 includes an internal combustion engine 10, a device 20, a heater 30 that air-conditions the interior 6 of the vehicle 5, a radiator 40, and a cooling device 50. The device 20 includes an EGR cooler 21 that cools EGR gas, a transmission 22, a transmission cooler 23 that cools oil in the transmission 22, and an oil cooler 24 that cools oil for lubricating the internal combustion engine 10. In the present embodiment, the device 20 only needs to include at least the transmission 22 and the transmission cooler 23, and may not include the EGR cooler 21 and the oil cooler 24. Further, the transmission 22 according to the present embodiment is specifically an automatic transmission (ATM). However, the configuration of the transmission 22 is not limited to this, and various transmissions such as a manual transmission (MT) can be used.

  The cooling device 50 includes a pump 51, a water jacket 52a formed inside the cylinder block of the internal combustion engine 10, a water jacket 52b formed inside the cylinder head of the internal combustion engine 10, a refrigerant path switching device 60, A temperature sensor 70a, a temperature sensor 70b, and a control device 80 are provided. Further, the cooling device 50 has a plurality of refrigerant paths through which the refrigerant returns to the internal combustion engine 10 after passing through the internal combustion engine 10. The cooling device 50 includes a transmission path 90, a heater path 91, and a radiator path 92 as the plurality of refrigerant paths. The transmission path 90 is a path through which the refrigerant that has passed through the internal combustion engine 10 passes through the device 20 (specifically, passes through the EGR cooler 21, the transmission cooler 23, and the oil cooler 24 in this order) and returns to the internal combustion engine 10. is there. The heater path 91 is a path through which the refrigerant that has passed through the internal combustion engine 10 returns to the internal combustion engine 10 through the heater 30. The radiator path 92 is a path through which the refrigerant that has passed through the internal combustion engine 10 returns to the internal combustion engine 10 through the radiator 40.

  The pump 51 is a refrigerant pumping device that pumps the refrigerant to the water jacket 52 a of the internal combustion engine 10. The specific configuration of the pump 51 is not particularly limited, and various water pumps such as a mechanical water pump driven by the power of the crankshaft of the internal combustion engine 10 or an electric water pump driven by a motor may be used. Can be used. In this embodiment, a mechanical water pump is used as an example of the pump 51. The refrigerant pumped from the pump 51 passes through the water jacket 52a and the water jacket 52b in this order, and flows into the refrigerant path switching device 60.

  The refrigerant path switching device 60 is an apparatus that switches the refrigerant flow path in response to an instruction from the control device 80. The refrigerant path switching device 60 according to this embodiment includes a device port 61 that supplies refrigerant to the transmission path 90, a heater port 62 that supplies refrigerant to the heater path 91, and a radiator port 63 that supplies refrigerant to the radiator path 92. And a rotary valve (rotary switching valve) capable of switching the open / closed state of these ports is used. Specifically, as an example of the refrigerant path switching device 60, a DC motor-driven multifunction valve is used. More specifically, this valve has a device port 61, a heater port 62, and a radiator port 63 by switching the rotational position of a rotary valve driven by a DC motor that operates in response to an instruction from the control device 80. Switch the open / close state. When the device port 61 is opened, the refrigerant can pass through the transmission path 90. When the heater port 62 is opened, the refrigerant can pass through the heater path 91. When the radiator port 63 is opened, the refrigerant can pass through the radiator path 92.

  As long as the refrigerant path can be switched as described above, the specific configuration of the refrigerant path switching device 60 is not limited to the rotary valve. As another example, for example, the refrigerant path switching device 60 includes a device valve that opens and closes the device port 61, a heater valve that opens and closes the heater port 62, and a radiator valve that opens and closes the radiator port 63 (that is, A configuration including three types of opening and closing valves may be used. Even in this case, the device port 61 can be opened and closed by opening and closing the device valve, the heater port 62 can be opened and closed by opening and closing the heater valve, and the radiator port 63 can be opened and closed by opening and closing the radiator valve. Can be opened and closed.

  The temperature sensor 70 a detects the temperature of the room 6 and transmits the detection result to the control device 80. The temperature sensor 70 b detects the oil temperature of the transmission 22 and transmits the detection result to the control device 80. The control device 80 controls the refrigerant path switching device 60. In the present embodiment, an electronic control unit (Electronic Control Unit) is used as an example of the control device 80. The electronic control device includes a microcomputer having a CPU (Central Processing Unit) 81, a ROM (Read Only Memory) 82, and a RAM (Random Access Memory) 83. The CPU 81 is a device having a function as a control unit that performs various arithmetic processes and control processes. The CPU 81 executes each step of the flowchart described later. The ROM 82 and the RAM 83 are devices having a function as a storage unit that stores information necessary for the operation of the CPU 81.

  FIG. 2 is a schematic diagram for explaining details of the operation of the refrigerant path switching device 60. The refrigerant path switching device 60 has six modes A to F as switching modes of paths through which the refrigerant passes. In the A mode, the device port 61, the heater port 62, and the radiator port 63 are all closed, and as a result, the refrigerant does not pass through any of the transmission path 90, the heater path 91, and the radiator path 92. That is, in this case, the refrigerant does not flow in the plurality of refrigerant paths of the cooling device 50. In the B mode, only the heater port 62 is opened. In this case, the refrigerant that has passed through the internal combustion engine 10 passes only through the heater path 91. In the C mode, the device port 61 and the heater port 62 are opened, and the radiator port 63 is closed. In this case, the refrigerant that has passed through the internal combustion engine 10 passes through the transmission path 90 and the heater path 91. In the D mode, the device port 61, the heater port 62, and the radiator port 63 are all opened. In this case, the refrigerant that has passed through the internal combustion engine 10 passes through all of the transmission path 90, the heater path 91, and the radiator path 92.

  In the E mode, only the device port 61 is opened. In this case, the refrigerant that has passed through the internal combustion engine 10 passes only through the transmission path 90. In the F mode, the device port 61 and the radiator port 63 are opened, and the heater port 62 is closed. In this case, the refrigerant that has passed through the internal combustion engine 10 passes through the transmission path 90 and the radiator path 92.

  Among the modes A to F described above, the C and D modes are modes in which the refrigerant passes through the heater 30 with priority, and the E and F modes are modes in which the refrigerant passes through the device 20 with priority. Here, as in the D mode of FIG. 2, the state in which the refrigerant that has passed through the internal combustion engine 10 (the refrigerant after passage) passes through the transmission path 90, the heater path 91, and the radiator path 92 is referred to as a first state. Further, as in the F mode of FIG. 2, a state in which the refrigerant that has passed through the internal combustion engine 10 does not pass through the heater path 91 but passes through the transmission path 90 and the radiator path 92 is referred to as a second state. When the oil temperature of the transmission 22 is equal to or higher than the predetermined value and the output request of the heater 30 is requested, the control device 80 according to the present embodiment is based on the temperature of the room 6 and the set temperature of the room 6. The refrigerant path switching device 60 is controlled so that the state (D mode) and the second state (F mode) are switched. The details of this control process will be described below with reference to a flowchart.

  FIG. 3 is a diagram illustrating an example of a flowchart executed when the control device 80 switches between the first state and the second state. The control unit (CPU 81) of the control device 80 repeatedly executes the flowchart of FIG. 3 at a predetermined cycle. It is assumed that the normal control is being executed at the first start time of the flowchart of FIG. The specific content of this normal control is not particularly limited, and for example, a predetermined mode selected from the A to F modes described above may be executed. Therefore, the description of the details of the normal control is omitted.

  In step S1, the control unit determines whether or not the oil temperature of the transmission 22 acquired based on the detection result of the temperature sensor 70b is equal to or higher than a predetermined value. In the present embodiment, a temperature that is lower than the upper limit temperature of the oil temperature of the transmission 22 by a predetermined temperature is used as the predetermined value in step S1. Further, as the upper limit temperature of the oil temperature of the transmission 22, a temperature that is considered to cause a problem in the transmission 22 when a state in which the oil temperature of the transmission 22 is higher than the upper limit temperature continues for a predetermined time is used. In this embodiment, 140 ° C. is used as an example of the upper limit temperature. And as an example of the predetermined temperature of step S1, 130 degreeC lower by 10 degreeC than 140 degreeC is used. When it determines with No by step S1, a control part performs normal control (step S2). After step S2, the control unit ends the execution of the flowchart.

  When it determines with Yes in step S1, a control part determines whether the oil temperature of the transmission 22 acquired based on the detection result of the temperature sensor 70b is more than upper limit temperature (140 degreeC) (step S3). . When it is determined No in step S3 (that is, when the oil temperature of the transmission 22 is 130 ° C. or higher and lower than 140 ° C.), the control unit determines whether there is an output request of the heater 30 (step S4). Specifically, step S4 according to the present embodiment is executed as follows. First, a heater switch operated by a user is disposed in the room 6 of the vehicle 5 according to the present embodiment. When the user desires to start the output of the heater 30, the heater switch is turned on. In step S4, the control unit according to the present embodiment determines whether or not the heater switch has been turned ON. If it is determined that the heater switch has been turned ON, it determines that there is an output request for the heater 30. .

  If it is determined Yes in step S4, the control unit determines whether the degree of divergence (ΔT), which is the difference between the temperature of the room 6 (hereinafter referred to as the room temperature) and the set temperature of the room 6, is equal to or less than a predetermined value. It is determined whether or not (step S5). Specifically, in step S5, the control unit acquires the room temperature based on the detection result of the temperature sensor 70a (that is, the room temperature is the actual temperature (actual temperature) of the room 6). In addition, the control unit acquires the set temperature of the room 6 set by the user of the cooling device 50. Then, the control unit calculates a divergence degree (ΔT) that is a difference between the acquired temperature of the room 6 and the set temperature, and the calculated divergence degree is stored in advance in a storage unit (ROM 82). It is determined whether the value is equal to or less than the value. Although the specific value of the predetermined value of step S5 is not specifically limited, -5 degreeC is used as an example in a present Example. When it is determined Yes in step S5, the control unit determines whether the degree of divergence (ΔT) is greater than a predetermined value (in this embodiment, −10 ° C. is used as an example) and is −5 ° C. or less. (Step S6).

  When it determines with Yes by step S6, a control part controls the refrigerant | coolant path | route switching apparatus 60 so that a 2nd state (F mode) may continue for a predetermined period (step S7). In this embodiment, 20 seconds is used as an example of the predetermined time in step S7. Next, the control unit controls the refrigerant path switching device 60 so that the first state (D mode) continues for a predetermined time (step S8). In this embodiment, 10 seconds is used as an example of the predetermined time in step S8. After step S8, the control unit ends the execution of the flowchart.

  When it is determined No in step S6, the control unit determines whether or not the degree of divergence (ΔT) is greater than a predetermined value (in this example, −15 ° C. as an example) and is −10 ° C. or less. (Step S9). When it determines with Yes by step S9, a control part controls the refrigerant | coolant path | route switching apparatus 60 so that a 2nd state (F mode) may continue for the predetermined time shorter than the case of step S7 (step S10). In this embodiment, 15 seconds is used as an example of the predetermined time in step S10. Next, the control unit controls the refrigerant path switching device 60 so that the first state (D mode) continues for a predetermined time longer than in the case of step S8 (step S11). In this embodiment, 15 seconds is used as an example of the predetermined time in step S11. After step S11, the control unit ends the execution of the flowchart.

  When it is determined No in step S9 (that is, when ΔT is −15 ° C. or lower), the control unit causes the refrigerant path so that the second state (F mode) continues for a predetermined time shorter than that in step S10. The switching device 60 is controlled (step S12). In this embodiment, 10 seconds is used as an example of the predetermined time in step S12. Next, the control unit controls the refrigerant path switching device 60 so that the first state (D mode) continues for a predetermined time longer than in the case of step S11 (step S13). In this embodiment, 20 seconds is used as an example of the predetermined time in step S13. After step S13, the control unit ends the execution of the flowchart.

  In addition, when it determines with Yes by step S3, when it determines with No by step S4, or when it determines with No by step S5, a control part is 2nd state (F mode) from the case of step S7. The refrigerant path switching device 60 is controlled so as to continue for a long predetermined time (step S14). As an example of the predetermined time in step S14, 30 seconds is used in the present embodiment. Next, the control unit ends the execution of the flowchart. Note that a large amount of refrigerant can be supplied to the transmission cooler 23 by executing step S14. Thereby, the oil temperature of the transmission 22 can be effectively reduced.

  As described above, the control unit of the control device 80 according to the present embodiment, when the oil temperature of the transmission 22 is equal to or higher than the predetermined value (130 ° C.) and there is an output request of the heater 30 (Yes in step S4). In addition, based on the temperature of the room 6 (actual temperature) and the set temperature of the room 6 (specifically, based on the degree of divergence ΔT), the first state (D mode) and the second state (F mode) The refrigerant path switching device 60 is controlled so as to be switched.

  Fig.4 (a)-FIG.4 (e) are figures which show an example of the timing chart at the time of the control apparatus 80 which concerns on a present Example switching between a 1st state and a 2nd state. Specifically, FIG. 4A shows an example of an oil temperature timing chart of the transmission 22, and FIG. 4B shows an example of an indoor temperature timing chart. 4 (c) shows an example of a timing chart of the opening degree of the device port 61, FIG. 4 (d) shows an example of a timing chart of the opening degree of the heater port 62, and FIG. 4 (e) shows a radiator port. An example of the timing chart of the opening degree of 63 is shown. Moreover, the horizontal axis of Fig.4 (a)-FIG.4 (e) is time.

Assume that there is a request for output from the heater 30 at time t _{0 on} the horizontal axis in FIGS. 4 (a) to 4 (e). As shown in FIG. 4C, the opening degree of the device port 61 is always 100% (fully open). As shown in FIG. 4A, the oil temperature of the transmission 22 is 130 ° C. or higher at time t ₁ . Referring to FIG. 4 (b), the degree of deviation between the indoor temperature and the set temperature (△ T) is, -15 ° C. next at time _{t 2,} -10 ° C. next at time _{t 3,} -5 ° C. At time _{t 4} It has become. As a result, as shown in FIG. 4 (d), the between time _{t 1} of time _{t 2,} the opening degree of the heater port 62 after reaching 0% 10 seconds, and has a 20 seconds 100%. Further, the opening degree of the heater port 62 is made the time between _{t 2} of time _{t 3,} and 100% for 15 seconds after reaching 0% for 15 seconds. Further, the opening degree of the heater port 62 is made from the time _{t 3} during the time _{t 4,} 100% for 10 seconds after a 20 sec 0%. Figure 4 opening of the radiator port 63 as shown in (d) is between the time _{t 0} of time _{t 1} is a predetermined value (a value lower than 100% greater than 0%), the time from the time _{t 1} until t ₄ has become a 100%, it has declined gradually in time _{t 4} or later.

In FIGS. 4 (a) Timing Chart of through Figure 4 (e), the time _{t 1} or time _{t 2} the following state corresponds to a state in which steps S12 and S13 in FIG. 3 is running, longer than the time _{t 2} time t ₃ is less state corresponds to a state where step S10 and step S11 in FIG. 3 are performed, a long time t ₄ less than that time t ₃ has been executed step S7 and step S8 in FIG. 3 Corresponds to the state.

  As described above, in the cooling device 50 according to the present embodiment, when the oil temperature of the transmission 22 is equal to or higher than a predetermined value (for example, 130 ° C.) and there is an output request of the heater 30, the indoor temperature and the indoor 6 The first state and the second state are switched based on the set temperature. In this case, when the oil temperature of the transmission 22 is equal to or higher than the predetermined value and the output request of the heater 30 is requested, the transmission 22 can be preferentially cooled by the refrigerant. The oil temperature rise of 22 can be effectively suppressed. Moreover, when it will be in the 1st state, since a refrigerant | coolant can be allowed to pass through not only the transmission 22 but the heater 30, heater performance can also be ensured. As described above, according to the cooling device 50, both of ensuring the heater performance and suppressing the increase in the oil temperature of the transmission 22 can be achieved.

  Further, as can be seen from the execution times of step S7, step S8, step S10, step S11, step S12 and step S13 in FIG. 3, the cooling device 50 according to the present embodiment has the indoor temperature and the set temperature of the indoor 6 The greater the degree of deviation (ΔT) from (ie, the lower the room temperature), the shorter the time in the second state and the longer the time in the first state. As a result, the greater the degree of deviation (ΔT) between the room temperature and the set temperature of the room 6, the greater the heater performance by supplying a larger amount of refrigerant to the heater 30 while suppressing an increase in the oil temperature of the transmission 22. We are trying to secure it effectively. Looking at this from the opposite viewpoint, the smaller the degree of divergence (ΔT) between the room temperature and the set temperature of the room 6 is, the larger the refrigerant is supplied from the transmission 22 while ensuring the heater performance. Effectively increases oil temperature.

  In addition, when it determines with Yes by step S6 of FIG. 3, when it determines with Yes by step S9, and when it determines with No by step S9, it will be in a 1st state after it will be in a 2nd state previously. However, the order of the first state and the second state is not limited to this. The control device 80 may be changed to the second state after first setting the first state. Specifically, when it is determined Yes in step S6, control device 80 may execute step S7 after executing step S8 first. Control device 80 may perform Step S10 after performing Step S11 first, when it is judged as Yes at Step S9. In addition, when it is determined No in step S9, the control device 80 may execute step S12 after executing step S13 first.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

DESCRIPTION OF SYMBOLS 5 Vehicle 10 Internal combustion engine 50 Cooling device 60 Refrigerant path | route switching apparatus 80 Control apparatus 90 Transmission path | route 91 Heater path | route 92 Radiator path | route

Claims (1)

A transmission path through which the refrigerant after passing through the internal combustion engine passes through the transmission of the vehicle;
A heater path through which the post-passage refrigerant passes through a heater that air-conditions the interior of the vehicle;
A radiator path through which the refrigerant after passing through the radiator of the vehicle;
A first state in which the post-passage refrigerant passes through the transmission path, the heater path, and the radiator path, and a second state in which the post-passage refrigerant passes through the transmission path and the radiator path without passing through the heater path. And a refrigerant path switching device capable of switching between,
When the oil temperature of the transmission is equal to or higher than a predetermined value and there is an output request of the heater, the first state and the second state are switched based on the indoor temperature and the indoor set temperature. And a control device for controlling the refrigerant path switching device.

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