JP3206404B2 - Engine speed control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine speed control device for an engine mounted on a vehicle.
The present invention relates to an engine speed control device for an internal combustion engine that simultaneously drives an air conditioner compressor.

[0002]

2. Related Background Art In recent years, vehicles equipped with an air conditioner (air conditioner) for performing air conditioning (heating, cooling) in a vehicle cabin have been increasing. Normally, a refrigerant compression device (compressor) of the air conditioner is operated by receiving power from an internal combustion engine that drives a vehicle, whereby air conditioning in the vehicle compartment is satisfactorily and sufficiently performed.

[0003] Compressors vary in compression capacity in accordance with the engine speed. In other words, the higher the engine speed, the better the air-conditioning capacity (mainly cooling and dehumidifying capacity) of the air conditioner. Therefore, when operating the air conditioner, normally, the minimum engine speed, that is, the target value of the idle speed (target idle speed) is set higher than the target set value of the normal idle speed without operating the air conditioner. And This also prevents the engine rotation from becoming unstable due to an increase in the load on the compressor.

[0004]

By the way, when the engine speed is increased as described above during the operation of the air conditioner, the fuel consumption naturally increases. Therefore, while the vehicle is running on a congested road where idling operation is continued for a long time, continuing to operate the air conditioner at a high engine speed will deteriorate fuel efficiency.

[0005] In particular, in an auto air conditioner which is always turned on during traveling, the idling speed is always kept high during idling operation even in a situation where the air conditioner is not required much. This is not preferable because fuel efficiency is extremely deteriorated. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an engine speed control device capable of preventing deterioration of fuel efficiency when an air conditioner is operating.

[0006]

According to a first aspect of the present invention, there is provided an engine speed control apparatus for an engine having an output side connected to a compressor of an air conditioner. Operating amount estimating means for estimating the operating amount of the air conditioner based on the integrated value of the engine rotational speed after the operating state is set, and a target value of the idle rotational speed of the engine when the air conditioner is activated. Idle speed control means for setting the target value of the idle speed to a second speed lower than the first speed when the operation amount reaches a predetermined amount. It is characterized by:

Therefore, when the air conditioner is activated, the target value of the idle speed of the engine is first set to the first revolution speed, and thereafter, the integration of the engine revolution speed after the air conditioner is activated is performed. When the operation amount of the air conditioner estimated based on the value reaches a predetermined amount, the target value of the idle rotation speed is set to the second rotation speed lower than the first rotation speed. As a result, the fuel consumption of the engine in a case where the idling operation is performed for a long time is reduced, and deterioration of fuel efficiency is prevented.

[0008] In the invention of claim 2, wherein the operation amount estimating means, integrated hands-stage or Rannahli of obtaining the integrated value, the idle speed control means, can with the integrated value reaches a predetermined value before SL amount operation is characterized in that said second rotational speed target value of the idle speed is regarded to have reached the predetermined amount.

Therefore, when the air conditioner is operated, the target value of the engine idle speed is first set to the first speed, and thereafter, the integration of the engine speed after the air conditioner is operated is set. can the value has reached the predetermined value
In this case, the target value of the idle speed is set to the second speed lower than the first speed. As a result, the fuel consumption of the engine is easily reduced based on the determination of the threshold value of the integrated value of the engine speed, and the deterioration of fuel efficiency is prevented.

Further, the invention according to claim 3 further comprises a state quantity detecting means for detecting a state quantity of the engine, wherein the idle speed control means is provided after the operation amount reaches a predetermined amount. When the state quantity of the engine reaches a predetermined state quantity, the target value of the idle speed is set to the first speed. Therefore, even after the operation amount of the air conditioner reaches the predetermined amount, when the state amount of the engine reaches the predetermined state amount, the target value of the idle rotation speed is set to the first rotation speed. Thereby, the state of the engine is preferentially maintained favorably.

Further, the invention 請 Motomeko 4, wherein the state quantity detecting means includes a coolant temperature detecting means for detecting a cooling water temperature of the engine, the idle speed control means,
When the cooling water temperature reaches a predetermined temperature, the target value of the idle speed and characterized in that said first rotational speed
Have . Thus, even after the operation amount of the air conditioner reaches the predetermined amount, when the cooling water temperature of the engine reaches the predetermined temperature, the target value of the idle rotation speed is set to the first rotation speed. As a result, a sufficient cooling performance is exhibited, for example, by ensuring the discharge amount of the engine-driven cooling water pump, and the engine is favorably maintained without overheating.

Further, in the invention according to claim 5 , the compressor has a clutch capable of connecting and disconnecting an output of the engine when the air conditioner is operated according to an operation state of the air conditioner. there comprising a total time means asking you to elapsed time from the connection, the idle speed control means, the operation amount is the amount of time elapsed since the connection is also the clutch even after reaching the predetermined amount When a specified time is reached, the target value of the idle speed is set to the first speed.

Therefore, even after the operating amount of the air conditioner reaches a predetermined amount, if the elapsed time from the connection of the compressor clutch reaches the specified time, the target value of the idle speed becomes the first rotation speed. It is a number. Accordingly, in a case where the effectiveness of the air conditioner is poor even though the idle operation or the operation close to the idle operation at the second rotation speed having a low target value is continued for a long time, the idle operation is performed. The target value of the number of revolutions is raised, and priority is given to enhancing the capacity of the air conditioner.

Further, the invention 請 Motomeko 6, further comprising a second timing means for determining the duration of the idling operation which is performed after the clutch is connected, the idle speed control means, the continued When the time reaches the set time,
It is characterized in that the idle speed target value regardless of the elapsed time and the first rotational speed. Thus, even after the air conditioner operation amount reaches a predetermined amount, if the continuation time of the idle operation performed after the clutch is connected reaches the set time, the time elapsed since the clutch was connected is reduced to the set time. Regardless, the target value of the idle speed is set to the first speed. Therefore, when the idle operation at the second rotation speed having a low target value is continued for a long time, the target value of the idle rotation speed is increased, and the enhancement of the capacity of the air conditioner is prioritized. Is done.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic configuration diagram of an engine speed control device of the present invention applied to an internal combustion engine (hereinafter, simply referred to as an engine) 1 mounted on a vehicle. Hereinafter, description will be made with reference to FIG.

As shown in FIG. 1, an engine 1 is a normal internal combustion engine including a cylinder head 2, a cylinder block 3, a crankcase 4, a piston 5, and the like.
A crankshaft 10 is supported by the crankcase 4, and the crankshaft 10 is connected to the piston 5 by a connecting rod 6. In the cylinder head 2,
An ignition plug 7 is provided facing the combustion chamber, and the ignition plug 7 is electrically connected to an electronic control unit (ECU) 40 described later.

Further, the cylinder block 3 is provided with a temperature sensor 8 for detecting the temperature of engine cooling water circulating in the water jacket 3a of the cylinder block 3. Further, the crankcase 4 is provided with an engine speed sensor 9 for detecting the engine speed based on the rotation of the crankshaft 10. And the intake pipe 1
2 is provided with an injector 13 for fuel injection. The temperature sensor 8, the engine speed sensor 9, and the injector 13 are electrically connected to the ECU 40.

The detailed configuration and operation of the engine 1 are known, and a detailed description thereof is omitted here. A cooling fan 16 for cooling the engine 1 is operatively connected to the crankshaft 10, and a compressor 20 for an air conditioner is connected via an annular belt 18. Specifically, the belt 18 is provided on a rotating portion of
Is connected to a clutch 22 for turning on and off the operation of the clutch. As the clutch 22, an electromagnetic magnet clutch or the like is used.

The compressor 20 is a device for converting the rotational output from the engine 1 into a linear motion and compressing a refrigerant circulating through a pipe 24 from an evaporator (evaporator) provided in the vehicle interior. It constitutes the main part. The compressed refrigerant is sent to a condenser (condenser) through a pipe 26. The configuration and operation of the air conditioner are known, and a detailed description thereof is omitted here.

On the input side of the ECU 40, in addition to the temperature sensor 8 and the engine speed sensor 9, a pipe 24
, A refrigerant temperature sensor 25 for detecting the temperature of the refrigerant of the air conditioner, an ignition switch (ignition SW) 30 for starting the engine 1, an air conditioner switch (air conditioner SW) 32 for turning on and off the air conditioner, An idle switch (idle SW) 34 and the like for detecting that the engine 1 is in an idling operation state are turned on / off in accordance with the opening degree of a throttle valve (not shown) which is provided upstream of the throttle valve and adjusts an intake air amount. Connected. On the other hand, the output side of the ECU 40 is electrically connected to the ignition plug 7, the injector 13, the clutch 22, and the like.

The clutch 22 is connected to the refrigerant temperature sensor 2
5 is turned on and off based on the refrigerant temperature signal from the control unit 5. That is, the clutch 22 is turned on and connected when the air conditioner is in a cooling state and the temperature of the refrigerant is equal to or lower than a predetermined temperature. On the other hand, when the temperature of the refrigerant reaches the predetermined temperature, the clutch 22 is considered to be sufficiently cooled and turned off. It is cut off and is in a cut state.

The cooling capacity of the air conditioner depends on the degree of compression of the refrigerant by the compressor 20. That is, the cooling capacity of the air conditioner
, That is, the engine speed Ne of the engine 1. Therefore, if the engine speed Ne is high, the compressor 20 will strongly compress the refrigerant, thereby increasing the cooling capacity of the air conditioner. vice versa,
The lower the engine speed, the lower the cooling capacity of the air conditioner. Therefore, normally, when operating the air conditioner by turning on the air conditioner SW 32, the minimum value of the engine speed Ne, that is, the target idling speed NID is changed to be higher than usual.

For example, a normal target idling speed N
If the ID is a value N0 (for example, 700 rpm), EC
U40 sets the target idling rotational speed NID to a value N1 (for example, 900 rp) based on the ON signal from the air conditioner SW32.
m) to a higher value. However, when the target idling rotational speed NID is the value N1 (for example, 900 rpm), more fuel is required than when the target idle speed NID is the value N0 (for example, 700 rpm). Therefore, in order to minimize the deterioration of fuel efficiency, the engine speed is controlled according to the operating condition of the air conditioner.

Hereinafter, the control content of the engine speed control according to the operating condition of the air conditioner will be described based on the flowcharts showing the control routines of FIGS. 2 and 3. In addition,
This control routine is always executed by the ECU 40 when the ignition SW 30 is on and the engine 1 is operating. Also, here, the description will be made mainly on the assumption that the air conditioner is in the cooling operation state.

First, in step S10 of FIG. 2, it is determined whether or not the air conditioner SW 32 is operated to turn on the air conditioner. If the determination result is false (No) and the air conditioner SW 32 is turned off (OFF) and the air conditioner is not operating, the process proceeds to step S11, where the target idling speed NID is set to the normal idling speed value N0 (for example, , 700 rpm). On the other hand, if the determination result in step S10 is true (Yes), the air conditioner SW3
If it is determined that the air conditioner 2 has been turned on and the operation of the air conditioner has been started, the process proceeds to step S12.

In step S12, an air conditioner timer (time measuring means as an operation amount estimating means) TMAC is set in order to measure an elapsed time t after the air conditioner SW 32 is turned on. This step S12 is performed by the air conditioner S
It is executed only immediately after W32 is turned on. That is,
The setting of the air conditioner timer TMAC is performed only immediately after the air conditioner SW 32 is turned on. The air conditioner timer TMAC is reset when the air conditioner SW 32 is turned off.

In step S14, the air conditioner timer TM
It is determined whether or not the measured time TAC of the AC has exceeded a predetermined time (predetermined amount) tA. Here, the predetermined time tA is set to a time at which the air conditioner can be considered to be sufficiently effective even when the engine 1 is left in an idling operation state. If the determination result is false and it is determined that the clock time TMAC has not reached the predetermined time tA, then step S16 is performed.
Proceed to. Normally, immediately after the air conditioner SW 32 is turned on, the air conditioner has not yet been sufficiently operated. In this case, the determination result is false, and the process proceeds to step S16.

In step S16, the integrated value Σ (Ne) of the engine speed Ne and its continuation time t after the air conditioner SW 32 is turned on by the ECU 40 (integrating means as operating amount estimating means). It is determined whether or not t) exceeds a preset predetermined value (predetermined amount) Xa. Just after the air conditioner SW32 is turned on,
The integrated value Σ (Ne · t) has not yet exceeded the predetermined value Xa,
If the result of the determination is false, the process proceeds to step S17.

In step S17, the target idling speed NID is set to the value N1 (first
, For example, set to 900 rpm). This routine is repeatedly executed, and the result of the determination in the step S14 becomes true, and it is determined that the clocking time TMAC has exceeded the predetermined time tA (TMAC> tA), or the result of the determination in step S16 becomes true and the integrated value Σ When it is determined that (Ne · t) exceeds the predetermined value Xa (Ne · t> Xa), the process proceeds to step S18. In addition, the clock time TM
There is a certain correlation between the relationship between AC and the predetermined time tA and the relationship between the integrated value Σ (Ne · t) and the predetermined value Xa, and the details will be described later (see FIGS. 4 and 5).

In step S18, based on the signal from the temperature sensor (cooling water temperature detecting means as state quantity detecting means) 8, it is determined whether or not the cooling water temperature TW of the engine 1 is lower than a predetermined value TW1 (for example, 113 ° C.). Is determined. This determination is to determine whether or not the engine 1 is in an overheat state. The judgment result is true and the cooling water temperature T
If W is equal to or less than the predetermined value TW1, then step S2
Go to 0. On the other hand, if the determination result is false and the cooling water temperature TW exceeds the predetermined value TW1, it can be determined that the engine 1 is in the overheat state, and the process proceeds to step S19.

In step S19, a water temperature timer TMT is set so as to measure an elapsed time t from the time when the cooling water temperature TW exceeds a predetermined value TW1. Then, step S
Proceeding to S17, the target idling speed NID is set to the value N1 (for example, 900 rpm) as described above. Thereby, the cooling fan 1 depending on the engine speed Ne
6, the overheating of the engine 1 is prevented, for example, by ensuring a sufficient discharge of an engine-driven cooling water pump (not shown).

In step S20, the routine is repeatedly executed, and it is determined whether or not the measured time TMT of the water temperature timer TMT set in step S19 has exceeded a predetermined time tW. This predetermined time tw is equal to the cooling fan 1
6, the time is set such that the engine 1 can be considered to be sufficiently cooled. If the determination result is false and the clock time TMT does not exceed the predetermined time tW, step S17
, The target idling speed NID is set to the value N1 (for example, 900 rpm).

On the other hand, if the decision result in the step S20 is true,
If it is determined that the counted time TMT has exceeded the predetermined time tW, the process proceeds to step S22. Step S2
In executing 0, the determination result is automatically set to true if the water temperature timer TMT is not set. In step S22, it is determined whether the clutch 22 of the compressor 20 is on (ON) and the compressor 20 is operating. Immediately after the air conditioner SW 32 is turned on, the compressor 20 is normally immediately activated. In this case, the result of the determination is true and the clutch 22 is on, and then, in step S26 in FIG. Proceed to.

In step S26 in FIG. 3, it is determined from the refrigerant temperature signal from the refrigerant temperature sensor 25 whether or not the clutch 22 has just been turned on. If the clutch 22 has just turned on, sets the compressor timer (total time means) TMCO in the next step S28, counting the time t elapsed after the clutch 22 is turned on. On the other hand, if it is not immediately after the clutch 22 is turned on, the step S28 is bypassed.

In step S30, it is determined whether or not the counted time TMCO has exceeded a predetermined time (specified time) tB. Immediately after the air conditioner SW 32 is turned on and the clutch 22 is turned on, the clock time TMCO is equal to the predetermined time t.
B, the determination result is false, and then step S
Go to 32. In step S32, it is determined whether or not the idle SW 34 is turned on (ON), that is, immediately after the idling operation is started. If it is immediately after the idle SW 34 is turned on, an idle timer ( second time measuring means) TMID is set in the next step S34, and the elapsed time t from when the idle SW 34 is turned on is counted. On the other hand, if it is not immediately after the idle SW 34 is turned on, step S34 is bypassed.

In step S36, it is determined whether or not the counted time TMID has exceeded a predetermined time (set time) tC. If the time count TMID has not reached the predetermined time tC as in the case where the idle SW 34 is turned on, that is, immediately after the start of idling, and the determination result is false, the process returns to FIG. 2 and proceeds to step S24. In step S24, the target idling speed NID is set to a value N2 (the second speed, for example, 800 rpm) (N1> N2) lower than the value N1 (idle speed control means).

That is, the predetermined time tA after the air conditioner SW 32 is turned on according to the result of the determination in step S14.
Has elapsed, or since the air conditioner SW 32 has been turned on based on the determination result of step S16, the integrated value Σ (Ne ·
If t) exceeds the predetermined value XA, a predetermined condition (the determination result of step S18 is true, and the determination of step S22
If the determination result is true, the determination results in steps S30 and S36 are false, it is considered that the air conditioner has been sufficiently cooled, and the target idling rotational speed NID is set to the normal idling rotational value N1 (for example, From 900 rpm) to a value N2 (for example, 800 rpm), the fuel consumption is reduced.

On the other hand, as described above, the cooling water temperature TW
Exceeds the predetermined value TW1, and the engine 1 is in an overheat state, or when the determination result in step S30 is true and the predetermined time tB has elapsed since the compressor 20 was activated, or when the determination result in step S36 is true. In idle S
If the predetermined time tC has elapsed since W34 was turned on, the target idling speed NID is held at the value N1 (for example, 900 rpm) in step S17 in FIG.

Here, when the predetermined time tB has elapsed since the operation of the compressor 20 or when the idle SW 34
The case where the predetermined time tC has elapsed since is turned on means, for example, a situation in which the outside air temperature is high and cooling is not effective. Therefore, when the outside air temperature is high, the target idling speed NID is set to the value N2 (for example, 800 rp) by executing step S24.
Even in the case of m), the target idling rotational speed NID is once increased to the value N1 (for example, 900 rpm) to enhance the cooling effect of the air conditioner. Thereby, it is expected that cooling will be rapidly promoted.

If the result of the determination in step S22 is false and the compressor 20 is not operating, the process proceeds directly to step S24, where the results of the determination in steps S14 and S16 are true and cooling is sufficiently performed. Accordingly, the target idling rotational speed NID is set to the value N2 (for example, 800 rpm) without going through the control routine shown in FIG.

The compressor timer TMCO and the idle timer TMID are reset when the clutch 22 of the compressor 20 is turned off. FIG. 4 shows the relationship between the elapsed time t, the target idling speed NID, and the engine speed Ne when, for example, the idling operation is continuously maintained after the air conditioner SW 32 is turned on based on the control routine. . More specifically, in the figure, at the time when the determination result in step S14 becomes true, a predetermined condition (when the determination result in step S18 is true and the determination result in step S22 is true, steps S30 and S36
(Determination result is false) is satisfied. In this case, as shown in FIG.
When W32 is turned on, the target idling speed N
The ID is set to a value N1 (e.g., 900 rpm), and after a predetermined time tA has elapsed, it is considered that sufficient cooling has been performed, and the target idling speed NID is set to a value N2 (e.g., 900 rpm).
800 rpm).

FIG. 5 also shows the air conditioner SW3.
2 shows the relationship between the elapsed time t after turning on 2 and the target idling rotational speed NID and the engine rotational speed Ne. In the same figure, the idling operation is not maintained and the engine rotational speed Ne is increased due to running or the like. This shows a situation in which it is appropriately raised and the result of the determination in step S16 becomes true. In this case, as shown in FIG.
The integrated value Σ (Ne · t) exceeds the predetermined value XA before the predetermined time tA elapses after the switch 2 is turned on, and when the elapsed time t becomes (tA−α), the target idling rotation is started. The number NID is reduced from the value N1 (eg, 900 rpm) to the value N2 (eg, 800 rpm).

In FIG. 5, the integrated value Σ (ΔNe · t) of the engine speed difference ΔNe and its continuation time t when the engine speed Ne exceeds the target idling speed NID (here, the value N1). Although the area is indicated by the area of the region P, this means that the area P corresponds to the area of the area P in FIG.
Indicates that the cooling proceeds faster than the case shown in FIG. The cooling amount corresponding to the area of the region P corresponds to the area of the region Q when it is replaced with the cooling amount when the value N1 (for example, 900 rpm) is maintained as it is, and the area of the region Q is , Value N1 (for example, 900 rpm)
And the value N2 (for example, 800 rpm) as the product of the difference .DELTA.NID and the time .alpha. (.DELTA.NID.alpha.). Accordingly, in a situation where the idling operation is not maintained and is appropriately raised, the cooling is sufficiently performed when the elapsed time t from when the air conditioner SW 32 is turned on becomes (tA-α). At this time (tA-α), the target idling speed NID is suitably reduced from the value N1 (for example, 900 rpm) to the value N2 (for example, 800 rpm).

FIG. 6 shows the temporal changes of the cooling water temperature TW and the target idling rotational speed NID when the idling operation is continued after the target idling rotational speed NID is set to the value N2 (for example, 800 rpm). However, in detail, FIG. 7 shows a situation where the cooling water temperature TW gradually increases and the result of the determination in step S20 becomes true. As shown in the figure, in a situation where the cooling water temperature TW gradually rises, that is, in a situation where the outside air temperature is high and the engine 1 is not sufficiently cooled at the idling speed N2 (for example, 800 rpm), the cooling water When the temperature TW reaches a predetermined temperature TW1 (for example, 113 ° C.), the target idling speed NID becomes a value N1 (for example, 900 rpm).
It is returned to. As shown in the figure, the state of the idling rotation value N1 (for example, 900 rpm) is continued for a predetermined time tW, whereby the cooling water temperature TW is favorably lowered. Thereafter, when the cooling water temperature TW reaches the predetermined temperature TW1 (for example, 113 ° C.) again, the target idling speed NID becomes the repetition value N1 (for example, 900 r).
pm).

As described above in detail, in the engine speed control apparatus of the present invention, when the predetermined time tA has passed since the air conditioner SW 32 was turned on and the air conditioner is considered to be sufficiently effective, or the integrated value Σ (Ne When t) reaches the predetermined value XA, the target idling speed NID is changed from the normal value N1 (for example, 900 rpm) to a low value N2 (for example, 800 rpm), so that the target idling speed NID is high. Without being left as it is, deterioration of fuel efficiency can be minimized by suitably reducing fuel consumption. In particular, in the present invention, the integrated value Σ
(Ne · t)
Good engine speed control that appropriately reflects the operation amount of the air conditioner can be realized.

The target idling speed NID is set to a value N.
2 (for example, at 800 rpm), the cooling water temperature TW of the engine 1 is maintained at the predetermined temperature TW1 (for example, 1).
13 ° C.), when a predetermined time tB has elapsed since the compressor 20 was operated, or when the idle SW3
In the case where the cooling is not easily performed as in the case where the predetermined time tC has elapsed since the turning on of the engine 4, the target idling speed NID is temporarily set to the value N1 (for example, 90).
0 rpm), the overheating of the engine 1 is suitably prevented, and the cooling, that is, the air-conditioning of the air conditioner is performed even in an operation state in which the operation at a low engine speed Ne or the idling operation is continued for a long time. The effect is suitably maintained.

In the above embodiment, the air conditioner SW 32
However, in the case of an automatic air conditioner, the air conditioner SW is often included in the ignition switch. In this case, the execution in step S10 in FIG. Ignition SW
May be determined.

[0048]

As described above in detail, according to the engine speed control device of the first aspect of the present invention, in the engine speed control device of the engine in which the compressor of the air conditioner is connected to the output side, engine speed integrated value since but starting with and air is the working state
When the operation amount estimating means for estimating the operating amount of the air conditioner, the idle speed of the target value of the engine when the air conditioner is an actuated state as a first rotational speed, which is then operated amount reaches a predetermined amount based on An idle speed control means for setting the target value of the idle speed to a second speed lower than the first speed, so that when the air conditioner is activated, the target of the engine idle speed is first set. The value is set to a first rotation speed. After that, when the operation amount of the air conditioner estimated based on the integrated value of the engine rotation speed after the air conditioner is activated reaches a predetermined amount, the target value of the idle rotation speed is set. The value can be a second rotation speed lower than the first rotation speed. Therefore, it is possible to reduce the fuel consumption of the engine when the idle operation is performed for a long time,
Deterioration of fuel efficiency can be suitably prevented.

In addition, according to the engine rotational speed control apparatus according to claim 2, operation amount estimating means, integrated hands stage for obtaining the integrated value
Or Rannahli, idle speed control means, since the integrated value is the second rotational speed target value of the idle speed reached was a can work movement amount is regarded to have reached the predetermined amount to a predetermined value, and air conditioning the first idle speed target value of the engine when it is the operating state is a first rotational speed, can then the integrated value of the engine speed from being air and the operating state has reached a predetermined value In (2), the target value of the idle speed can be set to the second speed lower than the first speed. As a result, it is possible to easily and suitably prevent the fuel consumption from deteriorating based on the determination of the threshold value of the integrated value of the engine speed.

According to the engine speed control device of the third aspect, the engine speed control device further includes a state amount detecting means for detecting a state amount of the engine, and the idle speed control means is provided after the operation amount reaches a predetermined amount. Even when the state amount of the engine reaches the predetermined state amount, the target value of the idle speed is set to the first rotation speed. Therefore, even after the operation amount of the air conditioner reaches the predetermined amount, When the state amount reaches the predetermined state amount, the target value of the idle speed can be set to the first speed. Thereby, the state of the engine can be preferentially maintained in a good condition.

An engine speed control device according to a fourth aspect of the present invention.
According to the above , the state quantity detecting means includes a cooling water temperature detecting means for detecting a cooling water temperature of the engine, and the idle speed control means sets a target value of the idle speed when the cooling water temperature reaches a predetermined temperature. than the first rotation speed, even after the operation amount of air reaches a predetermined amount, the cooling water temperature of the engine reaches a predetermined temperature, the first rotational speed target value of the idle speed Can be. As a result, sufficient cooling performance can be exerted, for example, by ensuring the discharge amount of the engine-driven cooling water pump, and the engine can be favorably maintained without overheating.

According to the engine speed control device of the fifth aspect , the compressor has a clutch capable of connecting and disconnecting the output of the engine during operation of the air conditioner according to the operating condition of the air conditioner. with a total time means asking you to elapsed time since the clutch is connected, the idle speed control means, the operation amount is the elapsed time is the prescribed time from the connected clutch even after a predetermined amount Is reached, the target value of the idle speed is set to the first speed. Therefore, even after the operation amount of the air conditioner reaches the predetermined amount, the elapsed time since the clutch of the compressor is connected is the specified time. Is reached, the target value of the idle speed can be set to the first speed. Therefore, in the case where the air conditioner is ineffective even though the idle operation or the operation close to the idle operation at the second rotation speed with the low target value is continued for a long time, the idle rotation speed , And the capacity of the air conditioner can be prioritized.

An engine speed control apparatus according to claim 6
According to the present invention , there is further provided a second time measuring means for obtaining a continuation time of the idling operation performed after the clutch is connected, and when the continuation time reaches the set time, the idling speed control means not the idle speed of the target value than the first rotation speed, even after the operation amount of air reaches a predetermined amount, setting the duration of the idling operation which is performed after the clutch is connected When the time has elapsed, the target value of the idle speed can be set to the first speed regardless of the elapsed time since the clutch was connected. Therefore, in a case where the idle operation at the second rotation speed with a low target value is continued for a long time, the target value of the idle rotation speed is increased to enhance the capacity of the air conditioner earlier. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an engine speed control device of the present invention.

FIG. 2 is a part of a flowchart showing an engine speed control routine.

FIG. 3 is the remaining part of the flowchart showing the engine speed control routine following the flowchart of FIG. 2;

FIG. 4 is a diagram showing a relationship between an elapsed time t and a target idling rotational speed NID when the idling operation is continuously maintained after the air conditioner SW is turned on.

FIG. 5 is a diagram illustrating a relationship between an elapsed time t and a target idling rotational speed NID when the idling operation is not maintained and the engine rotational speed Ne is increased after the air conditioner SW is turned on.

FIG. 6 shows a coolant temperature TW and a target idling speed NI.
FIG. 9 is a diagram showing a time change of D.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Cylinder head 3 Cylinder block 3a Water jacket 8 Temperature sensor (state quantity detection means) 9 Engine speed sensor 10 Crankshaft 13 Injector 16 Cooling fan 20 Compressor 22 Clutch 25 Refrigerant temperature sensor 30 Ignition switch (Ignition switch) 32 Air conditioner switch (air conditioner SW) 34 Idle switch (idle SW)

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takaki Yamauchi 5-33-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (72) Inventor Shigeharu Nakane 5-33-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (72) Inventor Tsuyoshi Tadanaga 5-33-8 Shiba, Minato-ku, Tokyo Inside Mitsubishi Motors Corporation (56) References JP-A-6-229273 (JP, A) JP-A-8-334048 (JP, A) JP-A-6-2595 (JP, A) JP-A-4-230415 (JP, A) JP-A-61-135953 (JP, A) JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02D 29/04 F02D 41 / 06,41 / 16 F02D 45/00

Claims (6)

(57) [Claims] 1. An engine speed control device for an engine having an output side connected to a compressor of an air conditioner, wherein the air conditioner is controlled based on an integrated value of the engine speed after the engine is started and the air conditioner is activated. An operation amount estimating means for estimating an operation amount of the engine; when the air conditioner is activated, a target value of an idle rotation speed of the engine is set to a first rotation speed; and when the operation amount reaches a predetermined amount, An engine speed control device, comprising: idle speed control means for setting a target value of the idle speed to a second speed lower than the first speed. Wherein said operation amount estimating means, wherein the integrated value determined integrated hands-stage or Rannahli, the idle speed control means, the integrated value is an odd pre SL amount operation reaches a predetermined value a predetermined amount 2. The engine speed control device according to claim 1, wherein the target value of the idle speed is regarded as the second speed assuming that the engine speed has reached a predetermined value. 3. The engine according to claim 1, further comprising a state amount detecting unit configured to detect a state amount of the engine, wherein the idle speed control unit controls the state amount of the engine even after the operation amount reaches a predetermined amount. 3. The engine speed control device according to claim 1, wherein a target value of the idle speed is set to the first speed when a predetermined state amount is reached. 4. The engine according to claim 1, wherein said state quantity detecting means includes an
Cooling water temperature detecting means for detecting the temperature of the cooling water, wherein the idle speed control means controls the cooling water temperature to a predetermined value.
When the temperature is reached, the target value of the idle speed is set to the
4. The method according to claim 3, wherein the number of rotations is 1.
Engine speed control device. 5. The compressor according to claim 1, wherein the compressor has a clutch capable of connecting and disconnecting the output of the engine during operation of the air conditioner in accordance with an operation state of the air conditioner. with a total time means asking you to time, the idle speed control means, when the operation amount reaches the elapsed time specified time from being connected even the clutch even after reaching the predetermined amount, the 3. The engine speed control device according to claim 1, wherein a target value of an idle speed is set to the first speed. 6. After the clutch is connected,
Second time measurement for determining the duration of the idle operation to be performed
Means, the idle speed control means, when the duration is set
The idle time, regardless of the elapsed time.
The target value of the number of revolutions is set to the first number of revolutions.
The engine speed control device according to claim 5, wherein