JP3323819B2 - Air conditioner control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an on / off control of an air conditioner in a vehicle having an automatic transmission and configured to cause a slip in a clutch mechanism such as a powder clutch or a torque converter to cause creep.

[0002]

2. Description of the Related Art Recently, a continuously variable transmission (Continuously Varia
For vehicles equipped with a ble transmission (hereinafter referred to as CVT), an electromagnetic powder type clutch is used to generate creep that causes the vehicle to run slowly when the shift lever is in the running position when idling without depressing the accelerator pedal. There is known a configuration in which the clutch mechanism is operated such that the clutch mechanism is operated by a predetermined initial set amount to cause a slip at this portion to generate a creep force. During creep running, the amount of intake air is increased by using idle speed control means capable of increasing or decreasing the amount of intake air within a certain range, and the engine output for creep traveling is improved.

On the other hand, when an air conditioner is operated,
In order to improve the engine output for the operation of the air conditioner, the idle speed is increased by idle speed control means. In particular, in vehicles equipped with a CVT, Japanese Unexamined Patent Publication No.
As disclosed in Japanese Patent Application Publication No. 039, the target value is corrected by the two factors of the actual gear ratio and the engine load in order to improve the running performance and the fuel efficiency, and the increase in the engine speed even when the engine is not idling is reduced. Some that are configured to make decisions have also been developed.

[0004]

However, in a place where the atmospheric pressure is low, such as at a high altitude, it is necessary to make the valve opening degree of the idle speed control means larger than that of a flat ground because intake air becomes lean. . As shown in FIG. 4, when a large load is applied to the engine under this condition, that is, when the creep force and the retreat force due to the gradient are substantially balanced on the uphill and the vehicle is stopped, the driver Operates the air conditioner, and when the load of the air conditioner is superimposed, in the range described as “insufficient” in FIG.
The increase in engine output by the idle speed control means makes it impossible to cover the increased load. As a result,
When the idle speed of the engine decreases, the engine controller that detects this reduces the air conditioner to prohibit the operation of the air conditioner. Then, the load on the engine decreases and the engine speed increases, so that the air conditioner operates again. As a result, the engine speed decreases again and the air conditioner is cut off again. As described above, when the air conditioner is operated in a state in which the increase in the engine output by the idle speed control means is near the limit, the air conditioner stabilizes, the air conditioner is repeatedly turned on and off, and the idle speed is moved up and down. And a situation unfavorable in terms of drivability may occur. Since such conditions are usually extremely unlikely,
The task itself was not recognized.

[0005]

SUMMARY OF THE INVENTION The present invention has been made for the first time in recognition of such a problem, and has been described in which a brake is not operated, a creep force is generated, and a vehicle is substantially driven. Under a predetermined condition in which the increase in the output of the internal combustion engine by the idle speed control means is expected to be substantially limited, such as when the engine is stopped and the intake pressure is equal to or less than a certain value, the operation of the air conditioner is prohibited to thereby increase the idle speed. This is intended to prevent the occurrence of undesired situations such as up and down movement in terms of drivability.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An air conditioner control method according to the present invention is directed to an internal combustion engine, an air conditioner driven by the internal combustion engine, and an intake air for maintaining the idle speed of the internal combustion engine at a target idle speed. An idle speed control means for performing feedback control by increasing / decreasing the air amount, and a clutch mechanism interposed between the internal combustion engine and the drive wheels and capable of freely changing the transmission torque are provided. Slip occurs in the clutch mechanism, is applied to a vehicle configured to generate a creep force, the brake is not operated, and is in a creep state, and the vehicle substantially stops, In addition, at least the condition that the intake pressure is equal to or less than a certain value, under a predetermined condition in which the increase in the output of the internal combustion engine by the idle speed control means is substantially limited, Characterized in that so as to prohibit the operation of air conditioners.

[0007]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram mainly showing a portion according to the present embodiment in an automobile as a traveling vehicle.
As shown in FIG. 1, this vehicle uses an engine 1 as an internal combustion engine as a power source, and connects the engine 1 and drive wheels 3 via a clutch mechanism 4 and a continuously variable transmission (hereinafter referred to as CVT) 2. It is made.

As shown schematically in FIG. 2, an engine 1 electrically controls an ignition timing,
For controlling the fuel injection amount and the like, a throttle sensor 91 for detecting the opening of the throttle valve 13, an intake pipe pressure sensor 92 for detecting the pressure of the intake pipe 14, an engine rotation (not shown) It has at least a number sensor. Further, the engine 1 is provided with idle speed control means 11 capable of freely controlling the idle speed. This idle speed control means 1
1 controls the valve opening of the idle speed control valve 12 provided in the middle of the intake pipe 14 with an ISC control signal e output from the engine controller 5 to change the intake air amount, and The engine speed can be controlled. In principle, the engine speed is controlled so that the idle speed detected by the engine speed sensor becomes a predetermined target idle speed. Although the illustrated example shows the bypass type, the CVT 2 which can also be applied to a direct-acting type in which the closing position of the throttle valve 13 is changed directly can be applied continuously and continuously. Any mechanism can be used as long as this function is satisfied.
An input sheave 21 and an output sheave 22 connected by a belt 23 are employed. The input sheave 21 and the output sheave 22 are configured so that the winding diameter of the belt 23 can be freely changed. The sheave driving means 7 for changing the diameter of each of the sheaves 21 and 23 changes this diameter. To continuously and continuously change the gear ratio. The sheave driving means 7 is controlled by a CVT control signal g output from the CVT controller 6.

[0009] The clutch mechanism 4 is provided with a CVT from the engine 1.
The clutch 41 is a hydraulic control type, for example, capable of freely changing the transmission torque transmitted to the clutch 2, a clutch operating lever 42 for intermittently driving the clutch 41, and a hydraulic cylinder connected to the clutch operating lever 42. 43
And an electromagnetic control valve 44 for adjusting the flow rate and direction of the hydraulic oil flowing into the hydraulic cylinder 43. This hydraulic oil is supplied by a hydraulic pump P driven by the engine 1. Thus, the electromagnetic control valve 44 is controlled by the clutch control signal f from the engine controller 5 to move the hydraulic cylinder 43 forward and backward, and the clutch operating lever 42 is moved to a desired position to realize the on / off or half-clutch state of the clutch 41. . Then, similarly to the torque converter vehicle, under a predetermined driving condition in which the shift lever is in the traveling position and the accelerator pedal is not depressed, the clutch operation lever 42 of the clutch mechanism 4 is moved to a predetermined position, and a half-clutch state is set. The vehicle is creeping slowly.

Further, an air conditioner 9 is mounted on the vehicle. An air conditioner cut-off signal h that can inhibit the operation of the air conditioner 9 even when an operation switch (not shown) is turned on is input to the air conditioner 9 from the engine controller 5. In addition, the vehicle is provided with a vehicle speed sensor 93 for detecting the vehicle speed, a brake sensor 94 for detecting the on / off of the brake, and the like.

In this embodiment, a program such as that shown in the flowcharts of FIGS. 2 and 3 is stored in the memory of the engine controller 5 and is repeatedly executed at regular intervals to control the air conditioner 9. I have. This flowchart called the air conditioner cut routine will be described with reference to FIG. Step S1 is called an acceleration cut routine, and is a part for performing an air conditioner cut when a driving force is required at the time of acceleration or the like. Then, the process proceeds to step S2.

In step S2, an intake pipe pressure sensor 92
Is lower than a predetermined value, that is, a predetermined value KPAA stored in the memory.
It is determined whether the temperature is lower than CT (for example, 630 mmHg). If the value is equal to or smaller than the predetermined value KPAACT, the process proceeds to step S3; otherwise, the process proceeds to step S8.

In step S3, the vehicle is substantially stopped, that is, the vehicle speed SPD becomes equal to a predetermined value KSPDACT (for example, 2).
km / h) is determined using the value of the vehicle speed signal a input from the vehicle speed sensor 93. If it is determined that the vehicle is substantially stopped, the process proceeds to step S4, and if not, the process proceeds to step S8. In step S4, it is determined whether or not the condition that the shift lever is in the traveling position during idling and the brake including both the foot brake and the hand brake (not shown) is OFF is satisfied. If the condition is satisfied, the process proceeds to step S5; otherwise, the process proceeds to step S8.

In step S5, the first counter CACC
The value of PA1 is counted up, the value of second counter CACCPA2 is cleared, and the process proceeds to step S6. In step S6, it is determined whether the value of the first counter CACCPA1 is equal to or greater than a constant KTACPA1. The value of the first counter CACCPA1 is a constant KTA
If it is equal to or higher than CCPA1, the process proceeds to step S7, and if not, the routine ends.

In step S7, 1 is substituted for an air conditioner cut flag XACCPA. As a result, an air conditioner cut in which the operation of the air conditioner 4 is prohibited is executed.
Then, this routine ends. On the other hand, in step S8, the value of the second counter CACCPA2 is counted up, the value of the first counter CACCPA1 is cleared, and the process proceeds to step S9.

In step S9, it is determined whether or not the condition that the value of the air conditioner cut flag XACCPA is 1 and the value of the second counter CACCPA2 is equal to or larger than the constant KTACPA2 is satisfied. Then, if the condition is satisfied, the process proceeds to step S10, and if not, the routine ends. Step S
At 10, 0 is substituted for the air conditioner cut flag XACCPA. This returns from the air conditioner cut. Then, this routine ends.

The present embodiment having such a structure operates as follows. In the idling state, a condition that the brake is off and the creep state (step S4 is satisfied), a condition that the vehicle is substantially stopped (step S3 is satisfied), and a condition that the intake pipe pressure PAPM is equal to or less than a certain value (step S3). If all of the conditions in step S2 are satisfied and this state is maintained for a certain period of time (step S6 is satisfied), the air conditioner is cut off assuming that the predetermined condition for air conditioner cut is satisfied (step S7). .
Here, the reason for adding the condition of step S6 that the predetermined time is maintained as the predetermined condition is that steps S2 to S2.
This is because if the air conditioner cut is suddenly executed when the condition 4 is satisfied, drivability may be adversely affected, and the air conditioner cut is not frequently executed and returned.

On the other hand, if any of the above conditions is not satisfied during the execution of the air conditioner cut and the state is maintained for a certain period of time (the condition for satisfying step S9), the process returns from the air conditioner cut (step S10). here,
The reason why the condition of step S9, which is that the air conditioner is cut off for a certain period of time, is added as the condition for returning from the air conditioner cut, mainly in order to prevent the air conditioner cut and execution from being performed frequently.

Therefore, according to the present embodiment, the operation of the air conditioner 9 is prohibited under the above-described predetermined condition in which the increase in the output of the engine 1 by the idle speed control means 11 is expected to be substantially at a limit. As a result, it is possible to prevent occurrence of a situation that is not preferable in drivability, such as repetition of turning on and off the air conditioner 9 and accompanying up and down movement of the idle speed, which may occur under the above-described predetermined conditions.

The present invention is not limited to the embodiment described above. For example, the same effect can be obtained by using an electromagnetic powder type clutch such as a powder clutch as the clutch mechanism. Further, the present invention can be applied not only to a vehicle equipped with a CVT but also to a vehicle equipped with a torque converter. In addition, the present invention is not limited to the illustrated example, and various modifications can be made without departing from the gist of the invention.

[0021]

As described in detail above, according to the present invention,
Under a predetermined condition in which the increase in the output of the internal combustion engine by the idle speed control means is expected to be substantially limited, the operation of the air conditioner is prohibited. It is possible to prevent the occurrence of an undesired situation in drivability, such as the accompanying rise and fall of the idle speed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a vehicle showing one embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of an engine in the embodiment.

FIG. 3 is a flowchart showing an air conditioner cut routine in the embodiment.

FIG. 4 is an operation explanatory view showing a state of an engine load in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine (engine) 11 ... Idle speed control means 4 ... Clutch mechanism 9 ... Air conditioner

Continuation of the front page (56) References JP-A-3-260345 (JP, A) JP-A-6-72136 (JP, A) JP-A-6-72138 (JP, A) JP-A-7-323723 (JP, A) , A) JP-A-64-9039 (JP, A) JP-A-62-48819 (JP, U) JP-A-63-113740 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB Name) B60H 1/32 623 B60H 1/32 625 B60H 1/32 622 B60H 1/00

Claims (1)

(57) [Claims] 1. An internal combustion engine, an air conditioner using the internal combustion engine as a drive source, and an idle speed for performing feedback control by increasing or decreasing an intake air amount to maintain the idle speed of the internal combustion engine at a target idle speed. and control means, wherein; and a clutch mechanism that can freely alter the interposed transmission torque between the internal combustion engine and the drive wheels, the idle speed
Air conditioner bracket that prohibits operation of air conditioner
The vehicle is configured to generate a creep force by causing the clutch mechanism to slip under a predetermined driving condition, and to apply a creep force. State
An air conditioner control method, wherein the operation of the air conditioner is prohibited under predetermined conditions including at least a condition that the vehicle is substantially stopped and the intake pressure is equal to or lower than a predetermined value.