JP3156207B2 - Intercooler water pump controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an electric water pump mainly provided in a cooling water circuit of an intercooler for a vehicle engine.

[0002]

2. Description of the Related Art Conventionally, as this type of control device, there has been known a control device in which when a water pump is operated at the time of idling of an engine, the charge / discharge balance and fuel efficiency are deteriorated. (JP-A-60-240823).

[0003]

By the way, even when the engine is idling, the temperature of the cooling water of the intercooler becomes considerably high during a hot restart or when the idling operation is continued for a long time due to traffic congestion. In this case, even if the water pump is operated, it takes time until the cooling water temperature of the intercooler decreases, and the intake air temperature does not readily decrease and drivability deteriorates.

In this case, it is conceivable to detect the cooling water temperature of the intercooler and operate the water pump when the cooling water temperature has reached a predetermined temperature or higher regardless of whether the engine is idling. (Including low-speed driving), the cooling performance of the radiator for the intercooler is reduced due to the traveling wind. Therefore, even if the water pump is operated, the cooling water temperature does not readily decrease, and the operating time of the water pump is prolonged. The discharge balance and fuel economy deteriorate.

[0005] In view of the above, it is an object of the present invention to provide a device capable of improving drivability without wastefully operating a water pump.

[0006]

In order to achieve the above object,
The present invention is a control apparatus of an electric water pump is interposed in the cooling water circuit of the intercooler, inter Ku
Means for detecting the cooling water temperature of the engine and means for comparing the cooling water temperature with a reference temperature to determine whether or not to operate the water pump.
It is characterized in that a means for changing the temperature to a higher temperature side during idling than in normal operation is provided.

[0007]

When the cooling water temperature exceeds the reference temperature even during idling, the water pump is operated to prevent the cooling water temperature from excessively increasing during idling, thereby preventing deterioration in drivability during normal operation after idling.

[0008] Here, according to the present invention, during normal operation is relatively low rather sets the reference temperature, and improve drivability by suppressing the intake air temperature low, whereas, during idling set relatively high reference temperature Thus, excessive operation of the water pump can be prevented.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 denotes an engine. An air cleaner 3, a supercharger 4, and an intercooler 5 are arranged in an intake passage 2 of the engine 1 in order from the upstream side.
, A throttle valve 6, and a fuel injection valve 7, a fuel is supplied from the fuel tank 8 to the fuel injection valve 7 via a fuel pump 9, and the electronic control circuit 10 controls the fuel injection valve 7, and the engine The fuel injection amount is controlled to increase or decrease according to the operating state of the engine.

An intake passage 2 is provided with an intercooler 5.
A bypass passage 11 for returning a part of the air passing through the supercharger 4 to the supercharger 4 is connected.
The supercharging pressure is controlled by interposing a supercharging control valve 12 driven by a motor 12a controlled by the electronic control circuit 10.

The intercooler 5 is of a water-cooling type and has a cooling water circuit 13 independent of a cooling water circuit (not shown) of the engine. Water pump 14 and radiator 15
The cooling water is circulated between the intercooler 5 and the radiator 15 by the operation of the water pump 14.

[0012] The electronic control circuit 10 includes a sensor 16 for detecting the opening θth of the throttle valve 6, a sensor 17 for detecting an intake pipe pressure P ₁ downstream of the throttle valve 6, sensor 18 for detecting the intake air temperature TA A sensor 19 for detecting the engine speed Ne, a sensor 20 for detecting the engine coolant temperature TWe, a sensor 21 for detecting the oxygen concentration O ₂ in the exhaust gas, and a supercharging pressure P upstream of the throttle valve 6. ₂ and a cooling water temperature TW of the intercooler 5.
The signal from the sensor 23 for detecting c is input to control the fuel injection valve 7 in accordance with the operating state of the engine determined based on θth, P ₁ , TA, Ne, TWe, and O ₂ , and controls the supercharging control valve 12 in accordance with P _2, and to control as follows water pump 14 further in accordance with the operating conditions and TWc engine.

This will be described in detail with reference to FIG.
In step 1, it is determined whether or not a service terminal, which will be described later, is short-circuited.
(For example, 74 ° C.) or more, TWe ≧ TWe
If it is s, the process proceeds to step S3, where TWc is the reference temperature T, which is a relatively low temperature at which heat radiation in the radiator 15 is not required
It is determined whether or not Wcs (for example, 10 ° C.) or more, and TWc ≧
If TWcs, the process proceeds to step S4 to determine whether or not the engine is in a high load operation. Note that TWcs is provided with hysteresis, and whether or not high-load operation is performed is determined by, for example, whether or not θth is fully opened.

At the time of high-load operation, the operation proceeds to step S5 to set the remaining time t of the subtraction timer to a predetermined set time ts, and then proceeds to step S6 to operate the water pump 14, and then proceeds to step S7. Water pump 1
The flag F indicating the operation state of No. 4 is rewritten to “1”.

Here, if the water pump 14 is operated during acceleration during high load operation, Ne drops temporarily due to an increase in load due to the starting current of the water pump 14, so that drivability deteriorates. During high load operation, the water pump 1
4, the water pump 14 does not operate during acceleration and the drivability does not deteriorate. When TWe is lower than TWes, the high load determination is not performed in step S4, and even when the engine is in the high load operation state, the water pump 14 does not operate until the TWc becomes relatively high as described later, and the engine is not operated. The warm-up performance at low temperatures is not impaired.

When TWe <TWes or TWc <TWcs
If it is not the time of high load operation, the process proceeds to step S8, where it is determined whether or not the flag F is "1". If the water pump 14 is not operating and F = 0, S9
Proceed to the step to determine whether or not idling operation,
If it is not the idling operation, the process proceeds to step S10, and the determination reference temperature TW for starting the operation of the water pump 14 is determined.
On is set to a relatively low temperature TWonL (for example, 45 ° C.), and when idling operation is performed, the process proceeds to step S11 to set TWon to TWonH (for example, 50 ° C.) higher than TWonL. Then, in step S12, it is determined whether or not TWc is equal to or greater than TWon, and TWc <TWo.
If n, the process proceeds to step S13, where the water pump 1
4 is kept in a stopped state, and a process of setting the flag F to “0” is performed in step S14, while TWc ≧ TWo
If n, the process proceeds to step S5 to set t to ts, and further proceeds to step S6 to operate the water pump 14 and set the flag F to "1" in step S7.

When the water pump 14 operates in this manner, F = 0 is determined in the step S8 from the next time, and the process proceeds to the step S15, where t = 0, that is, the set time ts from the start of the operation of the water pump 14. Is determined, and if t = 0, the routine proceeds to step S16, where it is determined whether or not the engine is idling. If it is not the idling operation, the process proceeds to step S17, and the reference temperature TWoff for determining the stop of the operation of the water pump 14 is set to a relatively low temperature TWoffL (for example, 35 ° C.).
On the other hand, if the idling operation is performed, the process proceeds to step S18, where TWoff is set to a value higher than TWoffL.
H (for example, 40 ° C.). Next, the process proceeds to step S19, where it is determined whether or not TWc is equal to or greater than TWoff.
If Wc ≧ TWoff, the routine proceeds to step S6, where the water pump 14 is continuously operated, and TWc <TWoff.
Is reached, the process proceeds to step S13, where the water pump 14 is stopped.

Thus, during normal operation, the water pump 14 operates at a relatively low temperature, and the intake air temperature is effectively cooled by the cooling water to improve drivability. On the other hand, during idling operation, the temperature becomes relatively high. Water pump up to 14
Does not operate, and deterioration of charge / discharge balance and fuel efficiency is prevented.
In addition, since the water pump 14 operates at a relatively high temperature even during idling operation, excessive temperature of the cooling water is prevented, and the cooling of the cooling water is delayed when shifting from the idling operation to the normal operation. It does not cause a problem that the ability deteriorates.

In steps S9 and S16, idling is determined when θth and Ne are equal to or less than a predetermined value using θth and Ne as determination parameters. However, the vehicle speed is added as a determination parameter, or only vehicle speed is determined as a determination parameter and low vehicle speed is determined. At times, it may be determined that the engine is idling.

When the operation of the water pump 14 is started, TWc is temporarily reduced as shown in FIG. 3 by the influence of the low-temperature cooling water cooled by the radiator 15.
In order to prevent the water pump 14 from being stopped due to such a temporary decrease in TWc, the above set time ts is set to, for example, 4 seconds in accordance with the time when the TWc is temporarily decreased. Until Ts elapses from the start of operation of the water pump 14 until ts elapses.
Regardless, the operation of the water pump 14 is continued.

Further, at the time of maintenance, the intercooler 5 is used.
When draining water, short the service terminal. According to this, the water pump 14 is operated by directly proceeding from step S1 to step S6, and water can be drained irrespective of TWc, which is convenient.

[0022]

As apparent from the foregoing description, according to the present invention, it is possible to prevent the cooling water temperature of the intercooler is excessively increased during idling, A Idorin <br/> in grayed relatively By operating the water pump in a high temperature range, excessive operation of the water pump can be prevented, and drivability can be improved without deteriorating charge / discharge balance and fuel efficiency.

[Brief description of the drawings]

FIG. 1 is a system diagram of an example of the apparatus of the present invention.

FIG. 2 is a flowchart showing a control program for a water pump.

FIG. 3 is a graph showing a change in water temperature at the beginning of operation of a water pump.

[Explanation of symbols]

5 Intercooler 10 Electronic control circuit 13 Cooling water circuit 14 Water pump 23 Water temperature sensor

Continuation of the front page (72) Inventor Takashi Ocho 1-4-1 Chuo, Wako-shi, Saitama Pref. In Honda R & D Co., Ltd. (56) References JP-A-2-23224 (JP, A) 16317 (JP, U) Hira 4-71743 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) F02B 29/04 F01P 7/16 504

Claims (1)

(57) [Claims] 1. A control device of an electric water pump is interposed in the cooling water circuit of the intercooler, inter
Means for detecting a cooling water temperature of the cooler, with and means for determining whether or not to operate the water pump and the cooling water temperature with the reference temperature, the engine the reference temperature
A water pump control device for an intercooler, characterized in that it comprises means for changing the temperature to a higher temperature side during normal operation than during normal operation .