JP2002276482A - Intake air temperature adjusting device for engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake air temperature adjusting device for an engine advantageously suppressing knocking of the engine, improving fuel consumption and reducing harmful components of exhaust gas. SOLUTION: This device is provided with an intake core 23 which heat- exchanges in contact with intake air fed to an intake port 18 of the engine 1, a heating means for heating the intake core 23, a forced cooling means for forcibly cooling the intake core 23 and a control device for controlling the heating means and the forced cooling means. The control device outputs a command for heating the intake core 23 by the heating means when load of the engine 1 is in a relatively small state. The control device outputs a command for forcibly cooling the intake core 23 by the forced cooling means at least an initial stage of a time when the load of the engine 1 transfers from the relatively small state to a large state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine intake air temperature control device having an intake core for exchanging heat by contacting intake air sent to an intake port of an engine.

[0002]

2. Description of the Related Art Conventionally, there has been known an engine intake air temperature control device having an intake core that exchanges heat by contacting intake air sent to an intake port of an engine (Patent Application Publication No. 20).
00-179414, published on June 27, 2000).

This device has an intake core that makes heat exchange with the intake air sent to an intake port of the engine, and heating means that heats the intake core by passing water heated by the engine through the intake core. According to this device, in the low load range of the engine, the water heated by the engine is passed through the intake core,
Intake air heating is performed in which intake air sent to an intake port of the engine is heated by an intake core. This improves the flammability in the low load range of the engine, improving fuel economy,
It is known that harmful components of exhaust gas are reduced.

[0004] Even in a high engine load region, when the intake air sent to the intake port of the engine is heated, the combustion performance is improved, but the engine may be easily knocked. The water heated by the engine is stopped from passing through the intake core, and the intake air heating is stopped.

[0005]

According to the above-described engine intake air temperature control apparatus, as described above, in a low engine load region, water heated by the engine is supplied to the intake core to cause combustion of the engine. The intake air that is sent to the room is heated by an intake core to improve the combustibility and reduce harmful components of exhaust gas. Also, in the high-load region of the engine, the supply of the water heated by the engine to the intake core is stopped, and the above-described intake heating is stopped. Due to the stagnation, knocking resistance is not always sufficient when the load on the engine is relatively large.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and suppresses engine knocking while improving fuel efficiency and reducing harmful components of exhaust gas when the load on the engine is relatively small. It is an object of the present invention to provide an engine intake air temperature adjusting device which is advantageous for the above.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, an engine intake air temperature control apparatus according to the present invention comprises: an intake core that makes heat exchange with an intake air sent to an intake port of an engine; Heating means for heating, forced cooling means for forcibly cooling the intake core, and a control device for controlling the heating means and the forced cooling means, the control device,
When the load of the engine is relatively small, a command to heat the intake core by the heating means is output, and at least at the initial stage when the load of the engine shifts from a relatively small state to a large state, the forced cooling means is used. It is characterized by outputting a command for forcibly cooling the intake core.

[0008] According to the engine intake air temperature control apparatus of the present invention, when the load of the engine is relatively small, the intake core is heated by the heating means. As a result, when the engine load is relatively small,
Since the intake air sent to the combustion chamber of the engine is heated, flammability is improved in a low load region of the engine, fuel efficiency is improved, and harmful components of exhaust gas are reduced.

[0010] Even when the engine load shifts from a relatively small state to a large state, knocking of the engine is likely to occur if the temperature of the intake air sent to the combustion chamber of the engine is increased. Therefore, at least at the initial stage when the load of the engine shifts from a relatively small state to a relatively large state, the intake core is forcibly cooled by the forced cooling means. As a result, the temperature of the intake air sent to the combustion chamber of the engine is positively reduced, and knocking of the engine is suppressed. Once the intake core is cooled, the temperature rise of the intake core is suppressed unless external heat energy is applied to the intake core, so that knock resistance of the engine is ensured.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram schematically illustrating the present embodiment. According to the present embodiment, the engine 1 includes a cylinder block 12 having a combustion chamber 11, a piston 13 reciprocating in the combustion chamber 11, a crankshaft 14 converting the reciprocating motion of the piston 13 into a rotary motion, and a cooling passage. 15 and the intake passage 1
7 and an exhaust valve 2 for opening and closing an exhaust port 21 at the end of an exhaust passage 20.
2 and an intake core 23 arranged in the intake passage 17. The engine 1 may be a gasoline type or a diesel type. The intake core 23 contacts and exchanges heat with the intake air sent to the intake port 18 of the engine 1, and adjusts the temperature of the intake air by the heat exchange. The intake core 23 may have heat transfer fins for performing heat exchange. The exhaust passage 20 is provided with a catalyst device 28 for purifying exhaust gas.

As shown in FIG. 1, the engine intake air temperature control apparatus according to this embodiment has a circulation passage 4, a bypass passage 5, and an (electrically driven) pump 6 functioning as a water conveying means.
And a control valve 7 provided at a connection portion 41x between the circulation passage 4 and the bypass passage 5. Since the heat of the engine 1 is transmitted to the water in the cooling passage 15 covering the engine 1, the water in the cooling passage 15 is heated. The radiator 3 is provided at the front of the vehicle and has a heat exchange function. The circulation passage 4 is drawn from an outlet 15 c of the cooling passage 15 of the engine 1, and is arranged to return to the inlet 15 a of the cooling passage 15 of the engine 1 via the radiator 3. The circulation passage 4 includes a first passage 41 that connects the outlet 15 c of the cooling passage 15 of the engine 1 and the inlet 3 a of the radiator 3, a first passage 41 that connects the outlet 3 c of the radiator 3 and the inlet 1 of the cooling passage 15 of the engine 1.
5a and the 2nd passage 42 connected. A control valve 7 and a pump 6 as a water transfer source are provided in the second passage 42. The bypass passage 5 is connected to a portion 41 m of the first passage 41 and a portion 41 x of the second passage 42 of the circulation passage 4, is connected in parallel to the radiator 3, and bypasses the radiator 3. . Therefore, the bypass passage 5
Does not flow through the radiator 3. The pump 6 has a water carrying / transporting capability, and causes water having heat in the cooling passage 15 of the engine 1 to flow through the circulation passage 4 as the pump 6 is driven. The pump 6 is driven to cool the engine 1 when the engine 1 is driven. As a driving source of the pump 6, a driving force of the engine 1 or other driving means such as an electric motor may be used, and the pump 6 may be driven when the engine 1 is driven.

FIGS. 2 and 3 schematically show the internal structure of the control valve 7. FIG. As shown in FIGS. 2 and 3, the control valve 7 is a three-way valve, and includes a base 71 having a hollow chamber 70 and a hollow chamber 70.
And a motor 73 for rotating the valve 73. The electric motor 74 has a motor shaft 74r rotatably supported by a bearing 74p and a motor body 74s. As the electric motor 74, for example, a stepping motor that rotates by a number corresponding to the number of input pulses can be exemplified. The electric motor 74 functions as an operation actuator that operates the control valve 7.
The base 71 of the control valve 7 has a first port 76 connected to the outlet 3 c of the radiator 3, a pump 6 side, and thus a cooling passage 1.
5 has a second port 77 connected to the inlet 15a, and a third port 78 connected to the outlet 5c of the bypass passage 5. The valve body 73 is provided with two valve openings 7 arranged side by side in the circumferential direction.
9 When the electric motor 74 is driven, the valve body 73 rotates around the motor shaft 74k of the electric motor 74, and the two valve ports 79 are adjacent to each other among the first port 76, the second port 77, and the third port 78. The two ports face each other, and the facing ports can communicate with each other. Electric motor 7
When the valve 4 is stopped, the valve body 73 can be stopped at an arbitrary position, so that the rotation position of the valve body 73 can be arbitrarily adjusted. Therefore, according to the control valve 7 described above, the valve port 79 is
The opening amounts of the port 76, the second port 77, and the third port 78 can be continuously changed, and each of these ports can be closed. FIG. 2 shows the second
A state is shown in which the bypass passage 5 and the pump 6 (the inlet 15a of the cooling passage 15) are connected by connecting the port 77 and the third port 78. In the state shown in FIG. 2, by adjusting the rotational position of the valve body 73, the degree of communication between the second port 77 and the third port 78 can be variably adjusted, and eventually the bypass passage 5 and the pump 6 (cooling passage) 15 can be variably adjusted, and the first port 76B, the second port 77B,
All of the third port 78B can be closed. FIG. 4 shows a state in which the outlet 3c of the radiator 3 and the pump 6 (the inlet 15a of the cooling passage 15) are communicated by communicating the first port 76 and the second port 77 via the valve port 79. In the state shown in FIG. 4, if the rotational position of the valve body 73 is adjusted, the first port 76 and the second port 77 are adjusted.
Of the radiator 3 and the pump 6 (the inlet 1 of the cooling passage 15) can be adjusted variably.
The communication degree of 5a) can be variably adjusted. By operating the control valve 7 so as to adjust the rotational position of the valve body 73 in this manner, the ratio between the amount of water flowing through the radiator 3 and the amount of water flowing through the bypass passage 5 can be changed.

As shown in FIG. 1, the engine intake air temperature control apparatus according to this embodiment has an outlet 3c of the radiator 3.
Feed passage 6 from the inlet to the inlet 23a of the intake core 23
6 and the second of the circulation passage 4 from the outlet 23 c of the intake core 23.
A core return passage 67 returns to a portion 42m of the passage 42 (a portion between the control valve 7 and the pump 6). The core supply passage 66 is provided with a second pump 6B and a second control valve 7B as a water transport source. The second control valve 7B provided in the core supply passage 66 is a three-way valve, and has the same structure as the control valve 7 described above. As shown in FIGS. 5 to 7, the second control valve 7B includes a base 71B having a hollow chamber 70B, a valve body 73B rotatably provided in the hollow chamber 70B, and a valve body 73.
And an electric motor 74B for rotating B. The electric motor 74B has a motor shaft 74r rotatably supported by a bearing 74p and a motor body 74s. Electric motor 7
As 4B, for example, a stepping motor that rotates by a number corresponding to the number of input pulses can be exemplified. The electric motor 74B functions as an operation actuator that operates the second control valve 7B.

The base 71B of the second control valve 7B includes a first port 76B connected to the outlet 3c of the radiator 3 and the second pump 6B, a second port 77B connected to the inlet 5a of the bypass passage 5 and the pump 6, and an intake core. 23 entrances 23
and a third port 78B connected to a. Valve body 73B
Has two valve ports 79B arranged side by side in the circumferential direction. When the electric motor 74B is driven, the valve body 73B rotates around the motor shaft 74k of the electric motor 74B, and the two valve ports 79B are adjacent to each other among the first port 76B, the second port 77B, and the third port 78B. Facing two ports,
The facing ports can communicate with each other. If the electric motor 74B is stopped, the valve body 73B can be stopped at an arbitrary position, so that the rotational position of the valve body 73B can be arbitrarily adjusted. Therefore, according to the above-described second control valve 7B, the valve port 79B has the first port 76B and the second port 77B.
B, the opening amount of the third port 78B can be made continuously variable, and the first port 76B, the second port 77B,
All of the ports 78B can be closed.

FIG. 5 shows the second port 77B of the second control valve 7B.
A state is shown in which the first passage 41, the inlet 5a of the bypass passage 5, and the inlet 23a of the intake core 23 are communicated by communicating the third port 78B. In the state shown in FIG. 5, if the rotational position of the valve body 73B is adjusted,
The communication between the port 77B and the third port 78B can be variably adjusted, and the entrance 5a of the bypass passage 5 can be adjusted.
In addition, the communication degree of the inlet 23a of the intake core 23 can be variably adjusted.

FIG. 7 shows the first port 76B and the third port 7
8B, the outlet 3c of the radiator 3
And a state in which the inlet 23a of the intake core 23 is communicated. In the state shown in FIG. 7, if the rotational position of the valve body 73B is adjusted, the first port 76B and the third port 78B are adjusted.
Can be variably adjusted, and the communication between the outlet 3c of the radiator 3 and the inlet 23a of the intake core 23 can be variably adjusted.

FIG. 8 is a block diagram related to the control device 8. As shown in FIG. 8, the control device 8 has an input interface circuit 81, a CPU 82, and an output interface circuit 84. A water temperature sensor 100 for detecting the temperature of water immediately after being discharged from the cooling passage 15 of the engine 1, a rotation speed sensor 101 for detecting the engine speed, a vehicle speed sensor 102 for detecting the vehicle speed, and a throttle opening for detecting the throttle opening A sensor 26 and an accelerator sensor 103 for detecting an accelerator depression amount are provided, and detection signals of these sensors are input to an input interface circuit 81 of the control device 8. The control device 8 controls the electric motor 74 of the control valve 7, the electric motor 74B of the second control valve 7B, the pump 6, and the second pump 6B. Specifically, the CPU 82 of the control device 8 determines the magnitude of the engine load based on one or more of water temperature, engine speed, vehicle speed, throttle opening, and accelerator depression amount, and outputs A command for controlling the electric motor 74 of the control valve 7, the electric motor 74B of the second control valve 7B, the pump 6, and the second pump 6B is output via the interface circuit 84 according to the magnitude of the load on the engine 1. For example, it is determined that the load on the engine 1 is large when the vehicle speed is low and the engine speed is low in spite of the large throttle opening and accelerator depression amount. When the vehicle speed is high and the engine speed is high, the throttle opening and the accelerator depression amount are small, it is determined that the load on the engine 1 is small.
Generally, when the vehicle is traveling on a flat road, when the weight of the vehicle is light, or the like, it is determined that the load on the engine 1 is small. When the vehicle is traveling on a steep uphill road or when the vehicle-mounted weight is heavy, it is determined that the load on the engine 1 is large.

According to the present embodiment, when the load on the engine 1 is relatively small, it is necessary to prevent the water in the cooling passage 15 from cooling the engine 1 too much. Therefore, the control device 8 performs a heating process for heating the intake core 23. That is, as shown in FIG. 9, the first port 76B of the second control valve 7B is closed while the first port 76 of the control valve 7 is closed.
The water in the cooling passage 15 of the engine 1 is prevented from flowing to the radiator 3. Further, the control device 8 connects the bypass passage 5 and the pump 6 by communicating the second port 77 and the third port 78 of the control valve 7, and transfers the water in the cooling passage 15 of the engine 1 to the first passage of the circulation passage 4. Portion 41 of passage 41
m, the inlet 1 of the cooling passage 15 of the engine 1 through the bypass passage 5, the third port 78 and the second port 77 of the control valve 7.
Return to 5a.

Further, when the load on the engine 1 is relatively small, the control device 8 turns off the second pump 6B, closes the first port 76B of the second control valve 7B, and opens the second port 77B and the second port 77B. By communicating the three ports 78B, the first passage 41 of the circulation passage 4 communicates with the inlet 23a of the intake core 23, so that hot water flowing out of the cooling passage 15 of the engine 1 does not flow to the radiator 3, but the circulation passage. 4 from the first passage 41 through the second control valve 7B to the inlet 23a of the intake core 23, pass through the intake core 23, and heat the intake core 23.

As described above, hot water flowing out of the cooling passage 15 of the engine 1 (ie, water not passing through the radiator 3)
From the first passage 41 of the circulation passage 4 to the intake core 23 through the second control valve 7B to heat the intake core 23,
The first passage 41 and the second control valve 7B function as heating means for heating the intake core 23.

As described above, the cooling passage 15 of the engine 1
After heating the intake core 23 with the hot water that has flowed out, the water is discharged from the outlet 23c of the intake core 23 through the core return passage 67, the portion 42m of the second passage 42, and the second passage 42 to the cooling passage 15 of the engine 1. To the entrance 15a. As described above, when the load on the engine 1 is relatively small, the hot water discharged from the cooling passage 15 of the engine 1 is not supplied to the radiator 3 but is supplied to the intake core 23 to heat the intake core 23. . Therefore, when the load on the engine 1 is relatively small, the combustion chamber 1
The intake air supplied to the exhaust gas 1 is heated, the combustibility of the engine 1 is improved, and harmful components contained in the exhaust gas are reduced.

On the other hand, when the load of the engine 1 shifts from a relatively small state to a large state, it is necessary to efficiently forcibly cool the engine 1 with water in the cooling passage 15 of the engine 1 and suppress overheating of the engine 1. There is. Therefore, the control device 8 performs a forced cooling process of the intake core 23 at the initial stage when the load of the engine 1 shifts to a relatively large state. That is, the first port 76 of the control valve 7 is closed, and the third port 78 and the second port 7 are closed.
7, the outlet 5c of the bypass passage 5 and the pump 6 are communicated with each other, the second port 77B of the second control valve 7B is closed, and the first port 76B and the third port 78B of the second control valve 7B are closed. And the second pump 6B is turned on. Thereby, as shown in FIG.
The hot water flowing out of the outlet 15c of the cooling passage 15 of the engine 1 is supplied to the inlet 3a of the radiator 3 through the first passage 41 of the circulation passage 4, passes through the radiator 3, and passes through the outlet 3c.
Discharge from. As a result, the hot water flowing out of the cooling passage 15 of the engine 1 is forcibly cooled by the radiator 3.

The water further cooled by the radiator 3 is
By driving the pump 6B, the outlet 3c and the core feed passage 6
6. The air is supplied to the inlet 23a of the intake core 23 through the first port 76B and the third port 78B of the second control valve 7B, passes through the intake core 23, and forcibly cools the intake core 23. Therefore, the core supply passage 66 for supplying the water cooled by the radiator 3 to the intake core 23 and the control valve 7B for opening and closing the core supply passage 66 can function as a forced cooling means for forcibly cooling the intake core 23. The water that has forcibly cooled the intake core 23 is
It is discharged from the outlet 23c of the intake core 23, and returns to the inlet 15a of the cooling passage 15 of the engine 1 through the core return passage 67 and the portion 42m of the second passage 42 of the circulation passage 4.

When the intake core 23 is forcibly cooled as described above, the water having heat retained in the intake core 23 is pushed out to the cooling passage 15 of the engine 1 through the core return passage 67. As described above, when the load of the engine 1 shifts from a relatively small state to a large state, the water cooled by the radiator 3 is supplied to the intake core 23 to forcibly cool the intake core 23. The intake air supplied from the port 18 to the combustion chamber 11 is actively cooled, and knocking of the engine 1 is suppressed.

In particular, since the water forcibly cooled by the radiator 3 is supplied to the intake core 23, the hot water staying in the intake core 23 can be pushed out, compared with the case where the intake core 23 is naturally cooled. As a result, the intake core 23 can be cooled quickly, which is advantageous in preventing knocking.

When the load of the engine 1 continues to be relatively large, the intake core 23 is forcibly cooled by water supplied to the intake core 23 through the radiator 3 and the core supply passage 66. You. Therefore, the intake core 23
If the forced cooling is continued for a long time,
It is necessary to keep the pump 6B turned on continuously, and energy is likely to be wasted. Also, unless the external heat energy is applied to the intake core 23, the intake core 23 is not substantially heated. Therefore, according to the present embodiment, when the state in which the load on engine 1 is relatively large for a longer time than the preset time, control device 8 issues a command to stop the forced cooling process of intake core 23. Output.
That is, the control device 8 stops the second pump 6B, and controls the first port 76B and the second port 7 of the second control valve 7B.
7B, the third port 78B is closed to prevent water passing through the radiator 3 from entering the inlet 23a of the intake core 23. When the state in which the load on the engine 1 is relatively large continues for the set time or longer, the control device 8 closes the third port 78 of the control valve 7 and simultaneously operates the first port 76 and the By connecting the two ports 77, the radiator 3 and the pump 6 (the inlet 15a of the cooling passage 15) are connected. As a result, the hot water in the cooling passage 15 of the engine 1 passes through the radiator 3 and is forcibly cooled by the radiator 3, and the first port 76 and the second
Cooling passage 1 of engine 1 through port 77 and second passage 42
Return to the entrance 15a of No. 5. When the state where the load of the engine 1 is relatively large continues for a set time or more,
Neither hot nor cold water flows through the intake core 23.

When the load of the engine 1 shifts from a relatively large state to a small state again, the state returns to the state shown in FIG. 9 again, and a heating process for heating the intake core 23 is performed. In other words, the control device 8 closes the first port 76 of the control valve 7 and closes the first port 76B of the second control valve 7B so that water in the cooling passage 15 of the engine 1 does not flow to the radiator 3. I do. Further, the control device 8 connects the bypass passage 5 and the pump 6 by communicating the second port 77 and the third port 78 of the control valve 7, and transfers the water in the cooling passage 15 of the engine 1 to the first passage of the circulation passage 4. Passage 4
The first portion 41m, the bypass passage 5, and the third port 78 and the second port 77 of the control valve 7 return to the inlet 15a of the cooling passage 15 of the engine 1. Further, when the load on the engine 1 is relatively small, the control device 8 turns off the second pump 6B while simultaneously turning off the second port 77 of the second control valve 7B.
B and the third port 78B communicate with each other, so that the first passage 41 of the circulation passage 4 communicates with the inlet 23a of the intake core 23, whereby hot water flowing out of the cooling passage 15 of the engine 1 is sent to the radiator 3. Without flowing, the air is supplied to the inlet 23a of the intake core 23 through the second control valve 7B to heat the intake core 23. After heating the intake core 23 with the hot water flowing out of the cooling passage 15 of the engine 1 as described above, the water is supplied from the outlet 23c of the intake core 23 through the core return passage 67, the portion 42m of the second passage 42, and the engine 1 To the inlet 15a of the cooling passage 15.

According to the present embodiment, as shown in FIG. 1, the engine 1 is provided with a heater core passage 90 for heating the passenger compartment. The heater core passage 90 includes a heater passage 91 connected to the second passage 42 of the circulation passage 4 and a heater passage 9.
1 provided in the heater core 92. One end 91 e of the heater passage 91 is connected to a portion 42 m of the second passage 42 of the circulation passage 4, and the other end 91 f is connected to the engine 1.
To the cooling passage 15. When the pump 6 is operating, the hot water in the cooling passage 15 of the engine 1 is
As shown in FIGS. 9 to 12, the outlet 15k of the cooling passage 15 is provided.
Then, the heater core 92 is heated through the heater passage 91 and the heater core 92, passes through the portion 42 m of the second passage 42, and the inlet 15 a of the cooling passage 15, and returns to the cooling passage 1 of the engine 1.
Returned to 5. The heated heater core 92 exchanges heat with the air in the passenger compartment to warm the air in the passenger compartment.

FIG. 12 shows C of the control device 8 according to the present embodiment.
4 shows an example of a control flowchart executed by a PU.
As shown in FIG. 12, in step S100, the various sensors described above, that is, the water temperature sensor 100, the rotation speed sensor 1
01, vehicle speed sensor 102, throttle opening degree sensor 26,
The output values of the accelerator sensor 103 and the like are read. In step S102, the magnitude of the load on the engine 1 is determined based on the output values of the various sensors. If it is determined that the load on the engine 1 is relatively small, step S10
Then, the program proceeds to Step 4, where a subroutine of a heating process for heating the intake core 23 is executed, and the process returns to the main routine. If it is determined in step S102 that the load on the engine 1 is relatively large, the process proceeds to step S106, and a subroutine for forced cooling of the intake core 23 is executed. The process further proceeds to step S108, and it is determined whether the forced cooling process of the intake core 23 has exceeded a set time. If the set time has not been exceeded, the flow returns to step S106, and the forced cooling process of the intake core 23 is continued. If the set time has elapsed, the process proceeds to step S110, in which the forced cooling process is stopped, and the process returns to the main routine.

(Others) According to the above-described embodiment, the control valve 7 provided in the circulation passage 4 is a three-way valve, and is provided at the connection portion 41x between the circulation passage 4 and the bypass passage 5. The first control valve, which is a two-way valve for adjusting the opening degree of the second passage 42 of the circulation passage 4, is not limited to this and is not shown. A second control valve, which is a two-way valve, may be provided.

According to the above-described embodiment, the pump 6 serving as a water transport source is provided in the second passage 42, but is not limited to this. In short, the pump 6 is provided with a passage to the radiator 3 or It may be provided at a position where water can flow through the circulation passage 4 so that the passage to the bypass passage 5 can be switched. Further, the second pump 6B, which is a water transfer source, is provided in the core supply passage 66, but is not limited to this. In short, the pump 6B supplies water passing through the radiator 3 to the intake core 23, Again, the cooling passage 15 of the engine 1
What is necessary is just to be provided in the position which can be returned to.

According to the above-described embodiment, the control valve 7B for sending water to the intake core 23 is provided in the core supply passage 66. In short, the water cooled by the radiator 3 is supplied to the intake core 23. Hot water in the cooling passage 15 of the engine 1 without passing through the radiator 3.
The control valve 7B may be provided at a location where the air can be supplied to heat the intake core 23. Further, in the above-described embodiment, as a representative heating means, forced cooling means,
Although these means are configured by switching the water passage communicating with the intake core, a heating heater is provided as a heating means, or a fan is provided as a forced cooling means, and forced cooling is performed by air blown by the fan. It may be configured as follows.

According to the above-described embodiment, when the load of the engine 1 is small, the first port 7 of the control valve 7
6, the first port 76B of the second control valve 7B is closed,
In addition, the second port 77B and the third port 78B of the second control valve 7B are communicated with each other to supply hot water flowing out of the cooling passage 15 of the engine 1 to the intake core 23.
However, the present invention is not limited to this. If the intake core 23 is excessively heated even when the load on the engine 1 is small, the second port 77B and the third port 78B of the second control valve 7B can be used.
, The first port 76B of the second control valve 7B is appropriately opened, hot water passing through the second port 77B and the third port 78B of the second control valve 7B, and water cooled through the radiator 3. And the mixed water may be supplied to the intake core 23 to suppress excessive heating of the intake core 23.

According to the above-described embodiment, the electric motors 74, 7 are used as the actuators for operating the control valves 7, 7B.
Although 4B is provided, the invention is not limited to this, and an actuator using an electromagnet may be used. The present invention is not limited to the embodiments described above and shown in the drawings, but can be implemented with appropriate modifications without departing from the scope of the invention. The terms described in the embodiments can be described in each claim.

[0035]

According to the engine intake air temperature control apparatus of the present invention, the intake core that contacts and heat exchanges the intake air sent to the intake port of the engine, and the intake air when the engine load is relatively small. A heating means for heating the core and a forced cooling means for forcibly cooling the intake core when the load on the engine is relatively large are provided. Therefore,
When the load of the engine is relatively small, the heating means heats the intake core. As a result, when the load on the engine is relatively small, the temperature of the intake air supplied to the intake port is increased, so that the combustibility is improved in a low load region of the engine, the fuel efficiency is improved, and the exhaust gas is improved. Harmful components are reduced.

In addition, at least at the initial stage when the load of the engine shifts from a relatively small state to a large state, the intake core is forcibly cooled by the forced cooling means, the intake air temperature is positively lowered, and engine knocking is reduced. Can be suppressed. According to the prior art described above, the intake core is naturally cooled. However, according to the engine intake air temperature control device of the present invention, the intake core is forced by the forced cooling means as compared with the case of natural cooling according to the prior art. Can be quickly cooled, which is advantageous in preventing engine knocking.

According to the engine intake air temperature control apparatus of the present invention, the heating means has a passage through which the water heated by the engine passes, and the forced cooling means has a passage through which the water forcedly cooled by the radiator passes. In this case, if the water forcedly cooled by the radiator is sent to the intake core by the forced cooling means, the hot water that has accumulated in the intake core can be pushed out. The intake core can be cooled more quickly than in the case of natural cooling, which is advantageous in preventing knocking.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically illustrating an engine intake air temperature adjustment device according to an embodiment.

FIG. 2 is a cross-sectional view schematically showing a control valve in a state where a bypass passage and a pump are communicated with each other.

FIG. 3 is a cross-sectional view schematically illustrating a control valve in different directions.

FIG. 4 is a cross-sectional view schematically showing a control valve in a state where a radiator and a pump are in communication with each other.

FIG. 5 is a cross-sectional view schematically showing a control valve in a communication state.

FIG. 6 is a cross-sectional view in a different direction schematically showing a control valve.

FIG. 7 is a cross-sectional view schematically showing the control valve in a state where the control valve is communicated with the control valve.

FIG. 8 is a block diagram showing an input and output relationship of the control device.

FIG. 9 is an operation explanatory diagram when the load on the engine is relatively small.

FIG. 10 is an operation explanatory diagram when the load of the engine shifts from a relatively small state to a relatively high state.

FIG. 11 is an operation explanatory diagram when the state in which the load on the engine is relatively high continues.

FIG. 12 is a flowchart illustrating an example of control executed by a CPU of the control device.

[Explanation of symbols]

In the figure, 1 is an engine, 15 is a cooling passage, 23 is an intake core, 3 is a radiator, 4 is a circulation passage, 5 is a bypass passage, 6 is a pump, 7 is a control valve, 74 is an electric motor, 7B
Indicates a control valve, 74B indicates an electric motor, and 8 indicates a control device.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) F02M 31/20 F02M 31/20 L 35/10 311 35/10 311B 311C

Claims (3)

[Claims] An intake core that contacts and exchanges heat with intake air sent to an intake port of an engine; a heating unit that heats the intake core; a forced cooling unit that forcibly cools the intake core; A control device for controlling the forced cooling unit, wherein the control device outputs a command to heat the intake core by the heating unit when the load on the engine is relatively small, An engine intake air temperature control device, wherein at least at the initial stage when the load of the engine is shifted from a relatively small state to a large state, an instruction to forcibly cool the intake core by the forcible cooling means is output. 2. The control device according to claim 1, wherein the control unit forcibly cools the intake core by the forced cooling means in an initial stage when the load of the engine shifts from a relatively small state to a relatively large state. An engine intake air temperature control device for outputting a command to stop the forced cooling of the intake core by the forced cooling means when the load of the engine continues to be relatively large. 3. The heating means according to claim 1, wherein said heating means has a passage for passing water heated by said engine and communicating with said intake core, and said forced cooling means is forcibly cooled by a radiator. An engine intake air temperature control device having a passage through which water passes and which communicates with the intake core.