JPH0233422A - Idle engine speed control device - Google Patents

Abstract

PURPOSE:To maintain the rotation of an engine adequately by correcting the actual aperture of an ISCV(Integrated Speed Control Valve-flow control valve) with an estimated correction value corresponding to the refrigerant discharge of an air-conditioning compressor, learning an estimated learning value and computing the initial value of the ISCV at the time of phase change. CONSTITUTION:An estimated correction value (b) corresponding to the refrigerant discharge of a variable capacity compressor M3 is obtained by means of a computing means M4 for controlling the aperture of an ISCV M1 at an idle time. The sum of the value (b) and the actual aperture of the valve M1, that is, the difference between the aperture corresponding to 100 percent of the refrigerant discharge and the aperture at the standing time of the compressor M3 is made as an estimated learning value and learned at a learning means M5. At the action starting time of the compressor M3, the initial aperture of the valve M1 is set from the sum of the normal learning value and the estimated learning value. The idle engine speed is thus controlled speedily regardless of the refrigerant discharge of the variable capacity compressor so as to prevent unnecessary climbing and lowering of rotation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an idle rotation speed control device for an engine equipped with an air conditioner using a variable capacity compressor.

[Prior Art] In idle rotation speed control, the intake air flow rate supplied to the engine via a bypass that bypasses the throttle valve is
The engine speed is controlled to a desired value by controlling the opening of a flow control valve (ISCV) provided in the bypass.

In particular, after the engine has completely warmed up, the opening degree of the flow control valve is feedback-controlled so that the actual engine rotation speed approaches the target rotation speed.

Furthermore, in an engine equipped with an air conditioner, when the compressor of the air conditioner is operating, the target rotational speed is increased by a predetermined amount corresponding to the load on the compressor.

When the compressor of the air conditioner is stopped during the above feedback control, the normal learning bond PC is learned to converge to the actual opening PMT of 15CV, and when the compressor is operating, the expected learning value PE is changed to 15CV.
It learns to converge to the value of the difference between the actual opening degree PMT of V and the normal learning bond PG, and even if there are changes over time such as deposits in the bypass, the desired intake air amount is always achieved. Is there something that quickly controls the engine speed?
JP-A-61-43247 rLearned value control method for idle rotation speed control, etc.).

On the other hand, in recent years, air conditioners using variable capacity compressors have been used.

Variable displacement compressors include through-vane and swash plate types, and both reduce the refrigerant discharge capacity of the compressor to reduce the load on the engine when the cooling capacity of the air conditioner is not very necessary. .

For example, in the swash plate type, the refrigerant discharge capacity is 50
There are some types that can change the refrigerant discharge capacity in two stages: 17% and 100%, and through vane types that can change the refrigerant discharge capacity in two stages, 17% and 100%.

In order to control the idle rotation speed of an engine equipped with an air conditioner using such a variable capacity compressor, it is possible to control the idle rotation speed according to the refrigerant discharge capacity of the compressor.
There is a system for setting the idle target rotational speed of the engine in the above-mentioned feedback control (Japanese Patent Laid-Open No. 58-220
939 r Idle rotation speed control device, etc.) 6 However, the idle rotation speed control when using a variable capacity compressor as described above does not learn the opening degree of the l5CV.

Therefore, if the bypass becomes clogged due to aging or the like, the engine speed cannot be quickly controlled when the compressor is operating or stopped.

Further, if an idle rotation speed control device that does not use a variable capacity compressor as described above is used with a variable capacity compressor as described above, the following problems occur.

In other words, in an idle rotation speed control device that does not take into account changes in the refrigerant discharge capacity of the compressor, the ISCV opening (normal learning (Iff P G')) when the compressor is stopped and the increase in the ISCV opening when the compressor is operating (estimated learning value) PE).

However, if the refrigerant discharge capacity of the compressor is 5.
If the estimated learned value PE is learned in the state of 0%, and then the air conditioner is turned on and the refrigerant discharge capacity of the compressor becomes 100%, the expected learned value PE when the refrigerant discharge capacity is 50% is the opening of l5CV. is not enough as
This may cause the engine rotation speed to decrease, or even cause the engine to stall.

Conversely, if the expected learning value PE is learned when the refrigerant discharge capacity of the compressor is 100%, and then the air conditioner is turned on and the refrigerant discharge capacity of the compressor becomes 50%, 1. Expected learning f when refrigerant discharge capacity is 1°0%
1mPE is too large as the opening degree of 15CV, and the engine speed becomes too high.

Furthermore, it is also possible to consider a configuration in which a plurality of prospective learning values PE are learned for each refrigerant discharge capacity of the compressor.

However, if this is done, it is expected that there will be fewer opportunities to learn each prospective learning value PE, and learning will not be sufficiently effective.

[Problems to be Solved by the Invention] The present invention provides, in an engine equipped with an air conditioner using a variable displacement compressor, by correcting a prospective learning value with a prospective correction amount according to the refrigerant discharge capacity of the compressor. In addition to obtaining accurate prospective learning values,
An object of the present invention is to provide an idle rotation speed control device that quickly controls the idle rotation speed to an appropriate value when the load condition of an air conditioner, that is, the refrigerant discharge capacity of a compressor changes.

[Means for Solving the Problems] In order to solve the above problems, the present invention employs the following means illustrated in FIG. 1.

That is, the gist of the present invention is to include a flow control valve (ISCV) Ml that is provided in a bypass that communicates the upstream passage and downstream passage of the throttle valve and that controls the engine rotational speed during idling. to calculate the target engine rotation speed at idle, and adjust the flow rate control valve M1 so that the engine rotation speed at idle matches the target engine rotation speed.
An idle rotation speed control device that increases the engine rotation speed by a predetermined amount by adjusting the control amount of the flow control valve M1 when the compressor M3 of the air conditioner M2 is operating. , the air conditioner M2 uses a compressor M3 whose refrigerant discharge capacity per unit time is variable, and the estimated correction amount is outputted in accordance with the refrigerant discharge capacity of the compressor M3. The amount calculating means M4 and the normal learning (direct PG) when the compressor M3 is not operating.
When the compressor M3 is operated, only the estimated learning value PE is used as the sum of the actual opening PMT of the flow control valve M1 and the estimated correction amount S, and the above. A learning means M5 that learns to converge to the difference from the normal learning bond PG, and a learning means M5 that learns to converge to the difference between the normal learning bond PG and the estimated learning value PE and the estimated correction amount when the state of the compressor M3 changes. and an initial opening setting means M6 for setting an initial opening PAC of the flow rate control valve M1.

Here, the compressor M3, which has a variable refrigerant discharge capacity and is used by the air conditioner M2, is the variable capacity compressor described in the related art, and either a through vane type or a swash plate type can be used.

Also, in the initial opening degree setting means M6. Compressor M
3, the state change is when the load on the compressor M3 changes, and when the compressor M3 starts or stops operating,
This occurs when the refrigerant discharge capacity changes.

[Function] In the present invention, the flow rate control valve (ISCV) during idling is
) When controlling the opening degree of Ml, first, an estimated correction amount calculation means M4 calculates an estimated correction amount according to the refrigerant discharge capacity of the variable capacity compressor M3.

When learning prospective learning (tuPE), the learning means M5 determines that the sum of the actual opening PMT of the flow control valve M1 and the estimated correction amount S, that is, the refrigerant discharge capacity of the compressor M3 is 100%. The difference between the opening degree of the flow control valve M1 when the compressor M3 is stopped and the opening degree of the flow control valve M1 when the compressor M3 is stopped is learned as a prospective learning value PE.

Furthermore, when the compressor M3 starts operating, the initial opening degree setting means M6 sets the normal learning bond PG and prospective learning ([
The sum of PE, the refrigerant discharge capacity of the Kombuchissa M3 is 1
The initial opening degree PAC of the flow rate control valve M1 is set as the value obtained by subtracting the expected correction amount according to the refrigerant discharge capacity of the compressor M3 from the initial opening degree of the flow rate control valve M1 when the opening degree is 00%.

As described above, by learning and using the normal learning bond PG and the expected learning ft1PE corrected by the expected correction amount S, the idle rotation speed control device of the present invention can
The idle rotation speed can be quickly controlled regardless of the refrigerant discharge capacity of the variable capacity compressor M3 and regardless of clogging of the bypass due to aging.

[Example] An embodiment of the present invention will be described.

In this embodiment, the compressor has a refrigerant discharge capacity of 50
The present invention is applied to an engine equipped with an air conditioner that can be varied in two stages: % and 100%.

FIG. 2 is a system configuration diagram of this embodiment.

In the intake passage 11 of the engine 10, a throttle valve 12 is provided.
is provided, and the amount of intake air into the engine body 10 is controlled by controlling the opening degree of the throttle valve 12.

A bypass passage 13 is formed to bypass the intake passage 11 in which the throttle valve 12 is inserted, and a flow control valve (ISCV) 20 is inserted in the bypass passage 13.

The opening degree of the I5CV20 is adjusted by a stepping motor 21, and the amount of intake air into the engine body 10 is controlled independently of the throttle valve 12.

When the amount of intake air into the engine body 10 is controlled by the throttle valve 12 or I5CV20, the amount of intake air is measured by an intake air amount sensor (not shown), and a predetermined amount is determined according to the measured amount of intake air. of fuel is injected by the fuel injection valve 15, and the engine rotation speed is controlled.

The operation of the stepping motor 21 and the fuel injection valve 15 is controlled by a control circuit 40, and therefore, although not shown, each detection signal is manually inputted to the control circuit 40 from the above-mentioned intake air amount sensor and others.

Therefore, when the throttle valve 12 is closed during idling, the control circuit 40 detects the state using the throttle sensor provided in the throttle valve 12, and
The opening degree of 5CV20 is controlled to maintain the engine speed at a predetermined target value.

Further, a compressor 31 of an air conditioner is connected to an output shaft 30 of the engine body 10 via an electromagnetic clutch 32 and a belt 33 .

The operation of this compressor 31 is controlled by a dedicated air conditioner control device 34, and the refrigerant discharge capacity is increased by 50% according to a signal from the air conditioner control device 34.
Switch to 2 levels of 100%.

The electromagnetic clutch 320 is also turned on and off by a signal from the air conditioner control device 34.

An air conditioner switch 35 for the driver's seat is connected to this air conditioner control device 34, and a human output signal line is also connected to the above-mentioned control circuit 4o.

FIG. 3 is a block diagram of the electric circuit portion centering on the control circuit 40.

The control circuit 40 includes a well-known CPU 41, RAM 42, RO
M43, backup RAM 44, 10 circuit 45, etc. are connected via bus 46.

A water temperature sensor 51 is connected to the I10 circuit 44 of the control port PI40.
．． A vehicle speed sensor 52, a throttle sensor 53 provided on the throttle valve 12. Crank angle sensor 549 Automatic transmission neutral switch 55, not shown. The signals from the air conditioning system 1all device 34 are input manually, and the stepping motor 21 of the 15CV20. Fuel injection valve 15. A control signal is output to the igniter 56.

The idle rotation speed control of this embodiment will be explained.

FIG. 4 shows an idle rotation speed feedback control routine in this embodiment, which is activated at predetermined intervals.

When this routine is started, first, in step 5100, it is determined whether or not feedback execution conditions for idle rotation speed control are met.

Here, for example, the water temperature is 70°C or higher, the engine rotation speed is 300 rpm or higher, and the vehicle speed is 2. If the speed is 0 km/hr or less, feedback control in steps 8105 to 5140 is performed. On the other hand, if the above conditions are not met, this routine is ended without doing anything.

When feedback control is started, step 5105
, the target rotational speed NF of the engine rotational speed is determined.

The target rotational speed NF is set to a predetermined fixed value by the air conditioner control device 34 and the neutral switch 55.
, is calculated by correcting each output of the water temperature sensor 51.

Subsequently, the current engine rotational speed NE is detected at the stem 5110.

This engine rotational speed NE is calculated from the output of the crank angle sensor 54.

Next, in step 5115, the difference ΔN between the target rotational speed NF and the actual engine rotational speed NE is calculated.

In step 5120, the absolute value of ΔN is compared with a predetermined reference value α, and if 1ΔN+>α, I 5CV2
Since it is necessary to adjust the opening of 0, process steps below 5125. On the other hand, if 1ΔN1≦α, 15CV2
Since the opening degree adjustment to 0 is not necessary, this routine ends.

In step 5125, the target rotation speed NF and the actual engine rotation speed NE are compared, and if NF>NE, in step 5130, the ISCV opening control value PMT is set to 1.
Increase by unit. On the other hand, if NF≦NE, the opening control value PMT of 15CV is decreased by 1 unit in step 5135.

Then, in step 5140, the stepping motor 21 is driven based on this ISCV opening degree control value PMT to set the desired opening degree of the I5CV 20, and this routine ends.

By repeatedly performing the above process, the idle rotational speed of the engine is always maintained at the target rotational speed NF.

However, with only the above feedback control routine, l
There is a delay in the opening degree of 5CV20 becoming desired.

Therefore, in this embodiment, when the compressor 31 is stopped,
Learn the opening degree of r5cv20 when the state changes such as during operation, and in the above case, use this learned value to adjust l5cv20.
The initial control opening degree is set at 20.

FIG. 5 shows a learning control routine for the initial control opening of l5CV20.

This routine is executed at predetermined intervals when the conditions for executing the feedback control routine described above are satisfied.

When the process starts, it is determined in step 5200 whether or not the compressor 31 is operating. If the compressor 31 is not operating, the process of steps S20''5 to 5225 is executed, and if it is operating, the process is executed in step S8230. ~826
Execute the process in step 5.

If the compressor 31 is stopped, step 5
At step 205, the aforementioned difference 1ΔN1 between the target rotational speed NF and the actual engine rotational speed NE is compared with a predetermined value β.

If 1ΔN1 is larger than β, this routine ends without performing the learning process because a load other than the compressor 31 is being applied, such as during power steering operation.

If 1ΔN1 is less than or equal to β, steps 9210 to 52
25, rsc when compressor 31 is not used
Normal learning (direct PC learning) which becomes the initial value of the opening degree of v.

In step 5210, the normal learning f1mPG and the current r
Compare it with the scv opening control amount PMT, and if PC>PMT, in step 5215 PG is reduced by 1/4 unit.

On the other hand, if PG>PMT is not true, it is determined in step 5220 whether PG<PMT, and if PG<PMT, PG is increased by 1/4 unit in step 5225. On the other hand, since PG=PMT otherwise, PC
Terminates this routine without changing.

In step 5200, if the compressor 31 is operating, in step 5jao, the step 5205
Similarly, 1ΔN1 is compared with the predetermined value β.

If 1ΔN1 is larger than β, this routine is terminated without performing the learning process, since a load other than the compressor/fusa 31 is being applied, such as during power steering operation.

If 1ΔN1 is less than or equal to β, steps S235 to S82
At step 65, prospective learning [
Learn PE.

The step 5235 determines whether the refrigerant discharge capacity of the kelp sensor 31 is 50%. This determination uses the output signal of the air conditioner control device 34.

If the refrigerant discharge capacity of the compressor 31 is 50%, in step 5240, a value obtained by subtracting the estimated correction amount S from the estimated learning value PE is set as the learning reference value a.

On the other hand, if the refrigerant discharge capacity of the compressor 31 is not 50%, that is, 100%, the estimated learning value PE is set to a. Note that the expected correction amount is a value determined in advance through experiments or the like.

Next, in step 5250, the sum of the normal study bond PG and a calculated in step 5240 or 5245 is compared with the current l5CV opening control amount PMT, and PG+
If a>PMT, in step 5225, PE is set to 1/
Reduce by 4 units.

On the other hand, if PG+a > PMT, it is determined in step 5260 whether PG+a<PMT, and if PG+a<PMT, PE is increased by 1/4 unit in step 5265. On the other hand, if not, P
Since C+a=PMT, this routine ends without changing PE.

Using the learning control routine as described above, the learned l
The normal learning value PG and expected learning value PE of the initial control opening of 5CV20 are used in the idle up control routine shown in FIG.

This idle up control routine is performed when idle conditions are met, when the air conditioner control device 3
4 when receiving a signal of a state change such as the start/stop of operation of the compressor 31 or a change in the refrigerant discharge capacity of the compressor 31, and is activated during the period control opening PA of 15CV20 in the feedback control routine shown in FIG.
Calculate C.

When this routine is started, it is determined in step 5300 whether the compressor 31 is on.

If the compressor 31 is on, it is determined in step 5305 whether the refrigerant discharge capacity of the compressor 31 is 50%.

Then, if the refrigerant discharge capacity of the compressor 31 is 50%, in step 5310, prospective learning (direct PE minus prospective correction amount ia) is calculated.

On the other hand, if the refrigerant discharge capacity of the compressor 31 is 100%, the prospective learning value PE is set to the value a.

Then, in step 5320, the sum of the value a calculated in step 5310 or 5315 and the normal study bond PG is set as the initial opening control amount PAC of 15CV20, and this routine ends.

On the other hand, if the compressor 31 is off, step 530
If the determination is 0, the normal study bond PC is set to the initial opening control amount PAC of the I5CV20 in step 5325, and this routine ends.

In this way, the TfJ ho control opening degree P of I5CV20
When AC is calculated, the control circuit 40 controls the actual opening PMT of the l5CV20 to match the initial control opening PAC, and then returns to the feedback control routine shown in FIG.

The idle rotation speed control device of this embodiment configured as described above performs predictive learning (iPE) that corresponds to when the refrigerant discharge capacity is 100% even if the refrigerant discharge capacity of the compressor 31 of the air conditioner changes. You can learn.

By using the prospective learning fi P E and the prospective correction amount corresponding to when the refrigerant discharge capacity is 100%, even if the refrigerant discharge capacity of the compressor 31 changes,
No unnecessary increase or decrease in engine rotational speed occurs.

Furthermore, even if the bypass becomes clogged due to aging, the engine speed will quickly reach the appropriate speed.

In this embodiment, the compressor 31 of the air conditioner uses a compressor whose refrigerant discharge capacity changes in two stages, but a compressor whose refrigerant discharge capacity can be arbitrarily changed may also be used. .

In that case, the estimated correction amount is calculated in advance, for example,
It may be changed according to the refrigerant discharge capacity of the compressor 31 using a table or the like provided.

[Effects of the Invention] The present invention learns an estimated learning value while correcting the actual opening degree of the 15CV using an estimated correction amount according to the refrigerant discharge capacity of the compressor of the air conditioner.

Further, the initial value of l5CV at the time of a change in the state of the compressor is calculated while correcting the estimated learning value using the estimated correction value.

Therefore, regardless of changes in the refrigerant discharge capacity of the compressor or clogging due to aging of the bypass, it is possible to learn the appropriate prospective learning value and control the ISCV, and regardless of changes in the compressor status, the number of engine revolutions is not required. No increase in rotation or decrease in rotation.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram illustrating the present invention, FIG. 2 is a system configuration diagram of an embodiment of the present invention, and FIG. 3 is a 7-degree diagram of the electric circuit portion (7) centering on the control circuit 40. Figure 4 is a flowchart of the feedback control routine, and Figure 5 is the learning control routine. Figure F2h and Figure 6 are flowcharts of the idle up control routine. Ml, 20...Flow control valve (ISCV), M2-1
゜Air conditioner, M3.31...Compressor, M4...Estimated correction amount calculation means, M5...Learning means, M6...Initial opening setting means, 10...Engine, 11... Intake passage, 12... Throttle valve, 13
...Bypass passage, 15...Fuel injection valve, 34...
・Air conditioner control device, 40...Control circuit representative Patent attorney Tsutomu Sadatsu (and 2 others) 2nd drawing 1 Fig. 3 Fig.

Claims (1)

[Scope of Claims] A flow control valve is provided in a bypass that communicates the upstream passage and the downstream passage of the throttle valve, and controls the engine rotational speed at idle, and also adjusts the target engine at idle according to the engine state. Calculate the rotation speed, adjust the control amount of the flow control valve so that the engine rotation speed at idle matches the target engine rotation speed, and adjust the control amount of the flow control valve when the air conditioner compressor is operating. An idle rotation speed control device that increases the engine rotation speed by a predetermined amount by an estimated correction amount calculation means for outputting a predetermined estimated correction amount according to the refrigerant discharge capacity; learning means for learning so that only the estimated learning value converges to the difference between the sum of the actual opening of the flow control valve and the estimated correction amount and the normal learning value when the compressor is in operation; The difference between the sum of the normal learning value and the above estimated learning value and the above estimated correction amount,
An idle rotation speed control device comprising: initial opening setting means for setting an initial opening of a flow rate control valve.