JPS61252839A - Acceleration control device for vehicle - Google Patents

Abstract

PURPOSE:To enable the number of idle revolutions to be always kept at a normal value, by providing a driving control stop instruction means, instructing the stop of instructing driving control for a step motor to a motor control means, and a diagnosing means diagnosing the trouble of a throttle valve energizing means. CONSTITUTION:The stop of driving control of a step motor (f) is instructed to a motor control means (g) by a driving control stop instruction means (h) when an acceleration controller (a) is located in a fully-closed position of a throttle valve (d) and the throttle valve (d) is right before full closing. A diagnosing means (i) diagnoses the trouble of a throttle valve energizing means (c). This enables the number of idle revolution to be always kept at a normal value.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vehicle accelerator control device in which a throttle valve is opened and closed by a motor in response to the operation of an accelerator operator.

(Background of the Invention) This type of device is known from Japanese Patent Publication No. 5B-25853, Japanese Patent Application Laid-Open No. 59-58131, etc., and a step motor can be used to open and close the throttle valve.

However, in conventional devices that use a step motor to open and close the throttle valve, the throttle valve remains open when the step motor cannot be controlled, causing the engine speed to abnormally increase regardless of accelerator operation.
Therefore, there was a risk that the vehicle would run out of control.

Therefore, a device has been proposed in which the throttle valve is biased in the closing direction by a spring or the like so that the throttle valve can be fully closed when the step motor cannot be controlled.

However, with this proposed device, it is not possible to control the opening and closing of the throttle valve with an accuracy higher than the feed interval of the step motor, and when the throttle valve opening is feedback-controlled, there is a mounting error in the detector that detects the opening. Since control errors occur due to fluctuations in the power supply voltage, the throttle valve cannot be accurately stopped to the fully closed position even if the accelerator operator is operated to the position corresponding to the fully closed throttle valve, and as a result, the engine's idle speed may become unstable. Problems such as the throttle valve colliding with the throttle chamber at high speeds have arisen.

Furthermore, if a problem occurs in the operation of a spring that biases the throttle valve in the closing direction, the driver cannot immediately confirm the problem, resulting in a delay in repair.

(Object of the Invention) The present invention has been made in view of the above problems, and its purpose is to accurately move the throttle valve to the fully closed position when the accelerator operator is operated to the position corresponding to the fully closed throttle valve. It is an object of the present invention to provide an accelerator control device for a vehicle that is capable of positioning and immediately detects a problem in the operation of a spring that biases a throttle valve in the closing direction.

(Structure of the Invention) In order to achieve the above object, in the present invention, drive control for the step motor is stopped when the accelerator operator is operated to a position corresponding to fully closing the throttle valve and the throttle valve is in a position immediately before fully closing. Thereafter, the throttle valve is driven to the fully closed position only by biasing means such as a return spring.

If the throttle valve is not fully closed within a predetermined period of time after the step motor stops driving, it is determined that there is a problem with the closing direction biasing means for the throttle valve.

Therefore, in the device according to the present invention, as shown in FIG. is being energized.

The opening and closing of the throttle valve d is performed by a step motor f, and the drive control of the step motor f is performed by a motor control means Q according to the operation amount of the accelerator operator a.

Further, when the accelerator operator a is in a position corresponding to fully closing the throttle valve d and the throttle valve d is just before fully closing, the step motor f
The motor control means Q is commanded to stop the drive control by the drive control stop command means, and after the drive control is stopped, the throttle valve d is activated by the throttle valve urging means C.
is biased and driven in its closing direction.

Further, in the diagnostic means i, the throttle valve d is
When the valve opening detection means e does not detect that the throttle valve biasing means C is fully closed, it is diagnosed that the throttle valve biasing means C is abnormal.

(Description of Embodiments) Hereinafter, preferred embodiments of the apparatus according to the present invention will be described based on the drawings.

In Figure 2, the accelerator pedal (accelerator operator>1
0 is detected by the accelerator potentiometer 12, and the detection signal is sent to the throttle valve control circuit 1.
4 is supplied.

This throttle valve control circuit 14 is mainly composed of a microcomputer, and the detection signal of the accelerator potentiometer 12 is input to its A/D converter 16.

Then, the A/D converter 16 converts it into a digital signal.
The detected signal from the accelerator potentiometer 12 is supplied to the CPU 18, and the 4-bit valve opening/closing control signal obtained by the CPU 18 is held by a latch 20.

The valve opening/closing control signal of the Zaraani latch 20 is provided by the motor driver 2.
2, and the windings 24a and 24b of the step motor 24 are each excited and controlled by the motor driver 22 in accordance with the valve opening/closing control signal.

The step motor 24 drives the rotating shaft of the throttle valve 26, and as a result, the throttle valve 26 is driven to open and close in response to the operation of the accelerator pedal 10.

Further, the throttle valve 26 is always urged in the closing direction by a return spring 28, and the throttle fully closed switch 30, which is driven by the rotating shaft of the throttle valve 26, is driven to switch when the throttle valve 26 is fully closed. .

A switching signal from the throttle fully closed switch 30 is supplied to the CPUA, and the CPU 18 detects from the switching signal that the throttle valve 26 is fully closed.

The warning lamp 32 is turned on by the CPU 18, and the lighting prompts the driver to repair or replace the return spring 28.

Note that the CPU 18 estimates and detects the opening position of the step motor 24 from the amount of feed thereof.

This embodiment has the above configuration, and its operation will be explained below.

Figures 3 and 4 show the slot l of the CPU 18 in Figure 2.
The process in FIG. 3 is a fixed-time interrupt process that is started at a predetermined period by an operating system (not shown).
The process shown in the figure is an oci interrupt process that is activated according to the motor speed determined by this fixed time interrupt.

In FIG. 3, first, the amount of depression of the accelerator pedal 10 (
The stroke amount 1) is read (step 100), and then the target opening degree of the throttle valve 26 (target number of T-stubs 5TE) is read (step 100).
P'') is determined based on the depression of the accelerator pedal 10 (step 102).

And the actual driving step number of the throttle valve 26 is 5TEP (
The deviation ε from the target number of steps 5TEP'' is calculated (step 104).

Furthermore, based on this deviation ε, the motor speed is calculated, the forward rotation, reverse rotation, and holding of the step motor 24 are determined, and the oci
The activation cycle of the interrupt is set, the flag regarding the motor rotation direction, etc. are set (step 106).

Next, it is determined from the stroke amount 1 of the accelerator pedal 10 whether or not the accelerator pedal 10 is in an unoperated state (step 108), and whether or not the actual number of driving steps 8 teeth EP of the step motor 24 is 4 or less. It is determined whether or not the throttle valve 26 is at the position just before being fully closed.
Step 110).

At this time, if the accelerator pedal 10 is not operated or the throttle valve 26 is not in the position immediately before fully closed, the no-excitation flag (NOTRQ) is reset (step 112), and the fully closed OK flag (OKFLG> is reset). (step 113).

Further, when the accelerator pedal 10 is not operated and the throttle valve 26 is in a position immediately before being fully closed, a non-excitation flag (NOTRQ> is set) (step 114).

In FIG. 4, when it is confirmed that the non-excitation flag (NOTRQ) is not set (step 116L), it is determined whether the rotational position of the step motor 24 should be maintained as it is.
It is determined whether to rotate forward or reverse (Step 1)
18).

At that time, when it is determined that the rotation is normal, 1 is added to the actual drive step number 5TEP (step 120),
Further, when it is determined that the reverse rotation is to be performed, 1 is subtracted from the actual drive step 5TEP (step 122>, and when it is further determined that the rotation is to be held, the actual drive step number 5TEP is subtracted from the actual drive step 5TEP).
The EP will remain as is.

Note that the actual drive step number 5TEP determined in steps 120 and 122 corresponds to the actual opening degree of the throttle valve 26, and is used to calculate the deviation ε.

Thereafter, the excitation pattern 1.2.3 shown in Table 1 below.
4 is selected in a predetermined order, and thereby the step motor 24 is controlled in forward and reverse directions, and the throttle 26 is driven to open and close (step 124).

Table 1 Furthermore, in Table 1, when excitation pattern 1.2.3.4 is selected, from terminal to terminal A, from terminal ■ to terminal B, from terminal A to terminal, Each rated excitation current flows from terminal B to terminal 100.

For example, when the pattern changes from pattern 1 to pattern 2, the rotation shaft of the step motor 24 is driven in the forward rotation direction, and when the pattern changes in the order of 3.4.1.2.3, the step motor 24 sequentially steps in the forward rotation direction. Driven.

Further, when the patterns are selected in the order of 1.4.3.2.1.4, the rotation shaft of the step motor 24 is sequentially driven step by step in the reverse direction.

By selecting the excitation patterns 1.2.3.4 in a predetermined order in this manner, the step motor 24 is fed in steps in the forward or reverse direction, and the throttle valve 26 is opened and closed, for example, in 1.8° increments. .

On the other hand, when the accelerator pedal 10 is not operated, the throttle 2
6 is in the position just before fully closed, and the non-excitation flag (NOTRQ)
> is set (step 116), the non-excitation pattern in Table 1 is selected (step 126), and the coil 24 of the step motor 24 is
Excitation to a and 24b is stopped, and the throttle valve 26
The closing direction is driven only by the return spring 28.

Here, the excitation is stopped when the throttle valve 26 is just before fully closed (STEP≦4), so the throttle valve 26 is fully closed before the speed of the throttle valve 26 in the closing direction increases. 26 does not collide with the throttle chamber at high speed, and the throttle valve 26 is not left closed even though the accelerator pedal 10 is not operated, and the engine is rotated at the normal idle speed.

Hey, the actual drive step number of the step motor 24 is 5TEP.
The reason why it is determined that the throttle valve 26 is in the position immediately before full closing when is 4 or less is because, for example, when the actual drive step number 5TEP is O and the first pattern 1 is selected when power is turned on to the system. When the magnetic fields strengthen each other and the rotor stops, the rotational position of the rotor does not necessarily coincide with the fully closed position of the throttle valve 26, and four patterns 1, 2, 3, and 4 are sequentially selected as in this embodiment. This is because in the method described above, an error occurs by a maximum of three steps, and the maximum number of error steps is less than four steps.

Here, after the drive control of the step motor 24 is stopped, whether or not the throttle valve 26 has been driven to the fully closed position by the return spring 28 is determined by monitoring the switching signal of the throttle fully closed switch 30. (Step 128 in Figure 3).

Then, before a period of 50 m5ec (a period sufficient for the throttle valve 26 to be fully closed) has elapsed after the drive control of the step motor 24 is stopped (step 130),
When the throttle fully closed switch 30 is switched and it is confirmed that the throttle valve 26 is fully closed, the fully closed state is OK.
A flag (OKFLG) is set (step 132
).

The normal operation of the return spring 28 is confirmed by the flag setting (step 134), in which case the third
The processing of the diagram is ended as is.

Further, if a period of 50 m5ec has passed since the drive control of the step motor 24 was stopped without confirming that the throttle valve 26 was fully closed (step 1
30 (affirmative judgment), fully closed OK flag (OKFLG>
is not set (step 1)
34), a failure flag (NGFLG>) is set (step 136).

Once this flag set is confirmed, step 138),
The warning lamp 32 is lit (step 140), thereby prompting the driver to repair the return spring 28.

As explained above, according to this embodiment, when the throttle valve 26 is at the position immediately before opening with the accelerator pedal 10 not being operated, the excitation of the step motor 24 that drives the throttle valve 26 to open and close is stopped, and then Since the throttle valve 26 is fully closed only by the biasing force of the return spring 28, the throttle valve 26 is fully closed while avoiding high-speed collision with the throttle chamber when the accelerator pedal 10 is fully closed.
6 can be accurately brought into a fully closed state.

Therefore, the durability of the throttle unit is improved, and it is possible to maintain the idle speed of the engine at a normal speed.

Further, according to this embodiment, it is possible to reduce the time and process required for installing the device on mass-produced vehicles, thereby reducing the cost.

In other words, conventionally, when assembling the pulse motor 24 and the throttle valve 26 into a mass-produced vehicle, they must be adjusted and set so that the throttle opening is O in pattern 1. Then, since the adjustment is automatically performed by the return spring 28,
This eliminates the need for time and effort, reducing manufacturing costs.

In particular, according to this embodiment, the return spring 28
Since an abnormality in the operation of the return spring 28 is automatically detected and the driver is prompted to repair it, it is possible to always maintain the return spring 28 in a state where it can operate normally.

Therefore, when the drive control of the step motor 24 cannot be performed due to a disconnection or the like, the throttle valve 24 can be reliably controlled.
can be driven fully closed, thereby preventing the vehicle from running out of control due to the inability to control the drive of the step motor 24, which is extremely desirable for safe vehicle operation.

Note that the above effects can be similarly obtained in this type of device in which the throttle valve opening degree detected using a potentiometer is used as the feedback amount.

(Effects of the Invention) As explained above, according to the present invention, when the accelerator operator is in the position corresponding to fully closing the throttle valve and the throttle valve is in the position immediately before fully closing, the throttle valve is driven to open and close. Since the drive control of the step motor is stopped and the throttle valve is energized by the energizing means, the throttle valve can be accurately driven to the fully closed position at that time, so that the engine speed is always kept at the normal idle speed. It becomes possible to make it a number.

Further, since the throttle valve is fully closed by the biasing means only when the throttle valve is about to be fully closed, a high-speed collision with the throttle chamber is prevented, and therefore, it is also possible to improve the durability of the throttle unit.

In particular, according to the present invention, since the abnormality of the biasing means is constantly monitored, it is possible to prompt repair by issuing a warning of the abnormality, and as a result, the normal operation of the biasing means can be ensured, and therefore To reliably prevent a vehicle from running out of control when the motor cannot be controlled.

[Brief explanation of drawings]

FIG. 1 is a claim correspondence diagram, FIG. 2 is a block diagram showing a preferred embodiment of the device according to the present invention, and FIGS.
It is a flowchart explaining the processing procedure performed by CPU18 in the figure. a...Accelerator operator b...Accelerator operation amount detection means C...Throttle valve biasing means d...Throttle valve e...Step motor f...Motor control means 0... - Drive control stop command means h...Diagnosis means i...Valve open/close detection means 10...Accelerator pedal 12...Accelerator potentiometer 14...Throttle valve control circuit 22...Motor driver 24 ...Step motor 26...Throttle valve 28...Return spring 30...Throttle fully closed switch 32...Alarm lamp

Claims (1)

[Claims] (1) A step motor that drives the throttle valve to open and close, a throttle valve biasing means that biases the throttle valve in the closing direction, an accelerator operation amount detection means that detects the operation amount of the accelerator operator, and an accelerator operator operation. a motor control means for driving and controlling the step motor according to the amount of the throttle valve; and a motor control means for commanding the motor control means to stop the drive control of the step motor when the accelerator operator is in a position corresponding to the fully closing of the throttle valve and the throttle valve is about to be fully closed. drive control stop command means; valve fully closed detection means for detecting a fully closed state of the throttle valve; A vehicle accelerator control device comprising: a diagnostic means for diagnosing whether the biasing means is abnormal.