JPS6196146A - Idling speed controller for engine - Google Patents

Abstract

PURPOSE:To make an idling speed maintainable to the specified value in spite of operation of a steering booster, by making a regulation value done by an idling regulating device compensable so larger in proportion as steering force is large, in case an engine provided with the steering booster. CONSTITUTION:In case of a device which installs a bypass passage 14, bypassing a throttle valve 12, in a suction passage 10 and controls an idling speed in a way of duty control over a solenoid valve 15 installed in the said passage 14, there is provided with a steering force sensor 19 which detects steering force (to be exact, a steering angle) in a steering wheel of a hydraulic power steering mechanism. And, at a control unit 16, first of all, map reference takes place for a power steering compensation term according to the angle velocity obtained with output of the said sensor 19 differentiated. Next, the said compensation term and a feedback compensation term of engine speed are added to a basic compensation term in time of idle running whereby a final compensation term is calculated, and a pulse in a duty ratio corresponding to this final compensation term is outputted to the solenoid valve 15.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to an engine idle speed control device. (Prior Art) Some engine idle speed control devices are disclosed in Japanese Patent Application Laid-open No. 55-156230. As shown in the publication, an electromagnetic means is provided as a rotation speed adjusting means for adjusting the idle rotation speed of the engine, and energization of the electromagnetic means is controlled based on a rotational deviation between the actual engine rotation speed and the idle target rotation speed. By controlling.

That is, there is a system in which the idle speed of the engine becomes equal to the target idle speed by performing feedback control. As the electromagnetic means, for example, a solenoid valve for adjusting the amount of intake air is used, and as the control of the energization, for example, duty control is performed. In other words, when the electromagnetic means is a solenoid valve for adjusting the amount of intake air, the amount of intake air is adjusted by adjusting the opening degree of this solenoid valve using duty control, and the idle speed of the engine is adjusted. become.

By the way, in the case of a device that adjusts the amount of intake air during idling operation of the engine so that the idling speed of the engine becomes a predetermined speed, it goes without saying that the device performs the feedback control described above. Even with open control, when the load on the engine fluctuates, the amount of intake air is increased (when the load increases) or decreased (when the load increases) in order to avoid fluctuations in the idle speed. (when the load is reduced). As a type of load on this engine, "steer"
For those equipped with a steering booster that boosts the non-long steering force, that is, power steering, the Utility Model Application No. 54-1
As shown in Publication No. 31226, in order to prevent the idle rotation speed from fluctuating due to changes in the load on the engine due to activation/deactivation of the steering booster, the hydraulic pressure of the steering booster is set to a predetermined level or higher. When this occurs, the steering booster is activated and, for example, by increasing the amount of intake air, fluctuations in the idling speed are prevented.

Conventionally, the amount of adjustment of the amount of intake air, etc. accompanying the operation of this steering booster has always been a constant amount.

However, in the conventional system as described above, it is not possible to reliably prevent fluctuations in the idle rotation speed in response to fluctuations in the load on the engine caused by the steering booster. In other words, the magnitude of the boost provided by the steering booster, that is, the magnitude of the load on the engine, is not constant, but varies depending on the driver's steering style. If the amount of adjustment by the rotation speed adjustment means is ignored and the amount of adjustment by the rotation speed adjustment means is kept constant, fluctuations in the idle rotation speed will be unavoidable. Of course, in a vehicle that performs feedback control, the idle speed will eventually settle to the target idle speed, but the idle speed will inevitably fluctuate for a while after the load changes. Furthermore, in the case of open control, it is not possible to compensate for fluctuations in the idle rotation speed due to the load fluctuations, and the engine may be left at a high rotation speed or the engine may stall.

(Object of the invention) The present invention has been made in consideration of the above circumstances, and
When the load on the engine fluctuates due to the steering booster while the engine is running at idle.

It is an object of the present invention to provide an engine idle speed control device that can effectively absorb this variation and more reliably maintain the engine idle speed at a predetermined value.

(Structure of the Invention) When the load on the engine fluctuates due to side operation due to the steering force booster, the present invention absorbs this fluctuation and maintains the idle speed at a predetermined level. The amount of adjustment required for this purpose is corrected in accordance with the magnitude of the steering force corresponding to the magnitude of the load.

Specifically, in an engine equipped with a rotation speed adjusting means for adjusting the idle rotation speed and a steering booster for boosting the steering force, as shown in FIG. 1, the steering force is detected. and a correction means that receives an output from the steering force detection means and increases the adjustment amount by the rotation speed adjustment means as the steering force increases.

(Example) Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 2, reference numeral 1 denotes an engine body, in which a combustion chamber 5 is defined by a cylinder block 2, a cylinder head 3, and a piston 4, and a crankshaft (not shown) is rotationally driven by the reciprocation of the piston 4. It is said to be a response-response type. An intake port 6 and an exhaust port 7 are respectively opened in the combustion chamber 5, and the intake port 6 is opened by an intake valve 8, and the exhaust port 7 is opened by an exhaust valve 9 in synchronization with the rotation of the crankshaft. It opens and closes at the right time.

In the intake passage 10 connected to the intake port 6, an air cleaner (path shown), an air flow meter 11, a throttle valve 12. A fuel injection valve 13 is provided.

Such an intake passage 10 is provided with a bypass passage 14 that bypasses the throttle valve 12, and a t magnetic valve 15 whose opening degree is adjusted by a duty control g++ is connected to this bypass passage 14. Of course, this bypass passage 14 is for flowing intake air for adjusting the idle rotation speed during idling, and the amount of intake air is adjusted by the solenoid valve 15. Of course, this solenoid valve 1
Reference numeral 5 constitutes an electromagnetic means as a rotation speed adjusting means for adjusting the idle rotation speed.

In Figure 3, 1.21R is the right front wheel, 211. is the left front wheel, and the left and right front wheels 21R and 21L are linked by a steering mechanism A.

In the embodiment, the steering mechanism A includes a pair of left and right knuckle arms 22R, 22L and tie rods 23R, 23, respectively.
L, and a relay rod 24 that connects the pair of left and right tie rods 23R123L. A steering mechanism B is linked to the front wheel steering mechanism A, and the steering mechanism B is of a rack and pinion type in this embodiment. That is, the relay rod 24
A rack 25 is formed in the handle 28 , and a pinion 26 that meshes with the rack 25 is connected to the handle 28 via a shaft 27 .
is connected to. As a result, when the handle 28 is turned to the right, the relay rod 24 is moved to the third position.
Displaced to the left in the figure, the navigation arm 22R122L is steered clockwise in the figure by an amount corresponding to the operating displacement amount of the handle 28, that is, the steering angle, around the rotation centers 22R' and 22L'. Ru. Similarly, /\endol28
When an operation is performed to turn the vehicle to the left, the left and right front wheels 21R and 21L are steered to the left according to the amount of displacement of the operation.

C in FIG. 3 is a hydraulic power steering mechanism, that is, a steering booster. To explain this power steering mechanism C, a cylinder device 29 is attached to the relay rod 24, and the cylinder 29 is fixed to the vehicle body.
2 rooms inside a 29b.

A piston 29d defined at 29c is integrated with the relay rod 24. The two chambers 29b and 29c within this cylinder 29a are connected to a control valve 32 whose input and output shafts are connected to the shaft 27 via piping 30 or 31.
It is connected to the. In addition, this control valve 32
In each, a pipe 34 extending from the reservoir tank 33 is provided.
．． 35 is connected to one pipe 35 which becomes an oil supply pipe.
An oil pump 36 driven by (the output shaft of) the engine body 1 is installed in the engine body 1.

In such a power steering mechanism C, as is known, when the shaft 27 is rotated in one predetermined direction, the pinion 26 is rotated in the same direction in response to this, and the relay rod 24 is rotated in the same direction. For example, it is displaced to the left in FIG. 3 and steered to the right. During this steering, the shaft 27
Oil is supplied into the chamber 29c of the cylinder device 29 according to the amount of rotation of the cylinder device 29 to assist in driving the relay rod 24 (boosting effect).Similarly, the shaft 27 is rotated in the opposite direction. Then, depending on the amount of rotation, the vehicle is steered to the left while receiving the boosting action of the cylinder device 29 (oil is supplied to the chamber 29b).

Again in FIG. 2, 16 is a control unit;
The control valve) 16 has a signal S
4 is input, while the control unit 16 outputs an output to the fuel injection valve 13 and the electromagnetic valve 15. Among the signals Sl''S4, the signal S is from the air flow meter 11 and corresponds to the intake air amount.The signal S2 is from the throttle sensor 17 and corresponds to the throttle opening. The signal Sx is from the rotational speed sensor 18 and corresponds to the engine rotational speed (actual rotational speed).
4 is from the steering force sensor 19, and is for detecting the steering force (more precisely, the steering angle) of the steering wheel 28.

The control unit 16 receives an intake air amount signal S,
In addition to controlling the fuel injection amount from the fuel injection valve 13 in a well-known manner based on the engine rotation speed signal Sff,
As will be described later, the solenoid valve 15 is controlled.

To explain the control of the solenoid valve 15 by the control unit 16, the solenoid valve 15 is opened only during idle operation, and the bypass passage 15 is opened according to the operating mode of the engine.
In this embodiment, the opening degree of the electromagnetic valve 15 is adjusted by duty control (intake air The larger the duty ratio is, the larger the opening degree becomes, and the idle speed is corrected to the upward side.

The control unit 16 that performs the above-mentioned control is
For example, it is configured by a microcomputer, and a specific example of its control will be described below with reference to the flowchart shown in FIG.

In this flowchart, since feedback control is performed to achieve the idle target rotation speed, the duty ratio for duty-controlling the solenoid valve 15 includes the basic duty ratio DB and the actual engine rotation speed. A feed pump duty ratio DFB is set corresponding to the rotational deviation between the target idle speed and the target idle speed. A duty ratio DLP is set, and the sum of these duty ratios DB, DFB, and DLP is finally output. In this embodiment, the steering force is determined by the rate of change of the steering angle of the shaft 27 (handle 28), that is, the angular velocity.

Based on the above, first, in step S1,
The engine speed (actual speed) N and throttle opening are read, and step S
In step 2, it is determined whether the vehicle is in an idling state. If it is determined in step S2 that the vehicle is not in an idling state, the process returns to step S1, and if it is determined that the vehicle is in an idling state, the process proceeds to step S3, where a basic correction term DB is calculated.

Thereafter, in step S4, the steering angle, that is, the steering angle θ, is read, and in step S5, the angular velocity ω is calculated by differentiating this steering angle 0. Then, based on this angular velocity ω, in step S6, a load correction term, that is, a power steering correction term DLP having a size corresponding to the angular velocity ω is calculated based on a map as shown in FIG. Of course, the larger the angular velocity ω (steering force), the thicker the power steering correction term DLP becomes.

Next, in step S7, a target rotational speed No. is calculated according to the operating state of the engine, for example, the warm-up state. Then, in step S8, it is determined whether the actual engine rotation speed N is larger than the upper limit range CNo+α of the idle target rotation speed, which is obtained by adding a predetermined rotation speed α (for example, 50 rpm) to the target rotation speed NO. Ru. This step S
In the judgment in step 8, if No+α≦N, the actual rotation speed is too high, so in order to correct this, Stella 7”S9
, a predetermined (previous) feedback correction term DF
After subtracting ΔDFB from B and setting it as a new feedback correction term DFB, the process moves to step S12. Also, in step S8 above, N, +α
When it is determined that N is not ≦N, it is determined in step SIO whether N is small with respect to No −α, which is the lower limit range of the idle target rotation speed, and when No−α≦N. Since the actual rotation speed is too low, in order to correct this, in step 311, the predetermined (previous) feedback correction term DFB plus ΔDFB is set as a new feedback correction term DFB, and then in step 31
Move to 2. Then, in step S13, No-
When it is determined that α≦N, the actual engine speed is within the allowable range of the target idle speed (N, -
Since α<N<No+α), in this case, the process directly proceeds to step S12.

In the step S12, the DB (basic)
By adding DLP (power steering correction) and DFB (feedback correction), a final correction term is calculated, and a pulse with a duty ratio corresponding to this final correction term is applied to the solenoid valve 15 in step 13. is output to. Of course, the larger the final correction value is, the larger the opening degree of the solenoid valve 15 is.
That is, the amount of intake air flowing through the bypass passage 14 increases, and the engine speed is controlled to increase.

As described above, through the processing in steps S4 to S6, intake air is generated to adjust the idle speed of the engine according to the magnitude of the steering force corresponding to the magnitude of the change in the load on the engine. The amount of adjustment is set.

Although the embodiments have been described above, the present invention is not limited thereto, and includes, for example, the following cases.

l'[) The intake air amount may be adjusted by adjusting the opening degree of the throttle valve 12 using electromagnetic means without providing a separate bypass passage.

・It can also be applied to open control of the idle speed of the engine.

・N) It can also be applied to diesel engines; in this case, the position of 4, for example, corresponding to the fuel injection amount of the fuel injection pump, may be adjusted by electromagnetic means.
For example, see Japanese Patent Application Laid-Open No. 57-97027).

(4) Steering The steering force can be detected by appropriate means such as the magnitude of the oil pressure in the power steering mechanism C or a twisting force acting on the shaft 27, for example. However, if this steering force is detected as in the embodiment, it will be possible to detect this steering force as quickly as possible, ensure sufficient control responsiveness, and reduce fluctuations in idle speed. This is preferable for more reliable prevention.

(Effects of the Invention) As is clear from the above description, the present invention effectively responds to changes in the load on the engine caused by the operation of the steering booster, and changes the idle speed due to the load changes. can be more reliably prevented. In particular, since the magnitude of the load on the engine that varies due to the above-mentioned steering booster is considered as the magnitude of the steering force 1, in other words, since the steering wheel operation is performed according to the driver's will, it is uniform in advance. The above fluctuations, which are difficult to specify, should be viewed as the magnitude of the steering force that can sufficiently respond to the driver's will.
This is extremely effective in preventing fluctuations in idle speed. .

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of the present invention. FIG. 2 is an overall system diagram showing one embodiment of the present invention. FIG. 3 is a system diagram showing an example of a steering booster section. FIG. 4 is a flowchart showing one control example of the present invention. FIG. 5 is a diagram showing the correspondence between steering angular velocity and power steering correction term. C: Power steering mechanism 1: Engine body lO: Intake passage 14: Bypass passage 15: Solenoid valve 16: Control unit 19: Steering force detection sensor 28: Handle Figure 1 L 8 Figure 3 Figure 5 Suderin 7 Negative balance support Ml

Claims (1)

[Claims] (1) An engine equipped with a rotation speed adjusting means for adjusting the idle rotation speed and a steering booster for boosting the steering force, the engine comprising: a steering force detection means for detecting the steering force; and the steering force. An engine idle speed control device comprising: a correction device that receives an output from a detection device and increases the amount of adjustment by the rotation speed adjustment device as the steering force increases.