JPH03267530A - Dush pot controller - Google Patents

Abstract

PURPOSE:To prevent the worsening of emission and fuel consumption by installing an already set opening degree correcting means which corrects the already set opening degree so as to become less when measurement time is longer than a prescribed time and corrects the already set opening degree so as to become larger when the measurement time is shorter than a prescribed time. CONSTITUTION:When measurement time is longer than a prescribed time, the time when a dush pot 11 starts operation is delayed by reducing the already set opening degree by an already set opening degree correcting means 16. Further, when measurement time is shorter than a prescribed time, the already set opening degree is increased by the already set opening degree correcting means 16, and the time when the dush pot 11 starts operation is accelerated. Accordingly, the time during which the dush pot 11 exerts action to a throttle valve 10 can be set constant, and operation can be stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dashbot I11 control device, and in particular to a control device for controlling a throttle valve connected to a diaphragm by guiding negative pressure of an intake manifold to a diaphragm chamber of a dashpot. The present invention relates to a dashpot control device that controls operations.

[Conventional technology]

Generally, a vehicle engine has a configuration in which the output is varied by a throttle valve operated by operating an accelerator pedal. The throttle valve closes when the engine shifts from a steady or accelerating state to decelerating operation, but if the throttle valve suddenly closes to the idle position, the air-fuel mixture becomes temporarily rich and emissions deteriorate. For this reason, a dashpot has traditionally been connected to the throttle valve, and after the throttle valve closes to a predetermined opening,
This dashpot is configured to slow down the closing speed of the throttle valve, thereby preventing deterioration of emissions. (Japanese Unexamined Patent Publication No. 61-205352).

An example of a conventional dashpot control device is shown in FIG.

As shown in the figure, the dashpot control device includes dashpot 1. It is composed of a negative pressure delay valve (VTV) 2 and a gas filter 3. The dashbot 1 is composed of a diaphragm 5 to which a rod 4 is attached and a coil spring 6, and a diaphragm chamber 7 in which the coil spring 6 is disposed.
is VTV2. It communicates with the intake manifold 8 via the gas filter 3 at a position downstream from the position where the throttle valve 9 is disposed. Further, the rod 4 is connected to a throttle valve 9.

Then, when the engine is decelerated and the throttle valve 9 reaches position a shown by the broken line in the figure, the negative pressure in the intake manifold 8 increases rapidly, and this negative pressure is applied to the gas filter 3. VTV2
is applied to the diaphragm chamber 7 via the diaphragm 5
is gradually displaced in the six directions of arrows against the coil spring 6.

The diaphragm 5 is connected to the throttle valve 9 via the rod 4, so that as the diaphragm 7 is slowly displaced in six directions, the throttle valve 9 gradually closes from position a to position Iib. It was said that

[Problem to be solved by the invention]

As described above, in the conventional dashpot control device, the spring constant of the coil spring 6 is selected so that when the throttle valve 9 reaches position ta, the diaphragm 5 starts to be displaced by the negative pressure in the intake manifold 8. However, if the coil spring 6 has fatigue or variations in spring constant,
The position where the dashbot 1 acts on the throttle valve 9 changes (that is, the position a changes), or the time at which the dashbot 1 acts on the throttle valve 9 becomes inconsistent, causing the dashpot control device to change. There was a problem that the operation became unstable.

For example, if sagging occurs or the spring constant is smaller than a predetermined value, the dashbot 1 operates with a low negative pressure, so the throttle valve 9 closes earlier than a normal one, resulting in poor emissions. Furthermore, if the spring constant is larger than a predetermined value, the dashbot 1 will not operate easily even if the intake manifold 8 reaches a predetermined negative pressure, and it will take a long time for the throttle valve 9 to close. The cost will worsen.

The present invention has been made in view of the above points, and an object of the present invention is to provide a dashpot control device that can stabilize the operation of a dashbot.

(Means for Solving the Problems) Fig. 1 is a diagram showing the principle of the present invention.As shown in the figure, in the present invention, when the throttle valve (10) reaches a preset opening degree, the dashbot (11) Diaphragm chamber (12)
The diaphragm chamber (12) is provided with a dashpot drive means (14) that introduces negative pressure into the diaphragm chamber (12) and applies a dashpot action to the throttle valve (1o) against the biasing force of a spring means (13) installed inside the diaphragm chamber (12). In the dashpot control device, the throttle valve (10) changes from the first opening degree to the first opening degree by applying negative pressure to the diaphragm chamber (12).
a measuring means (15) for measuring the time until reaching a second opening degree which is lower than the opening degree of the first opening degree; Predetermined opening correction means (16) corrects the predetermined opening to become smaller, and corrects the predetermined opening to become larger when the measured vf interval is shorter than a preset predetermined time. It is characterized by this.

[Effect]

In the dashpot control device configured as described above, the measuring means (15) can measure the time it takes for the throttle valve (10) to reach the second opening degree from the first opening degree.

For example, when the spring constant of the spring means (13) is larger than a predetermined set value, the throttle valve 10 reaches the predetermined opening degree and negative pressure is applied to the diaphragm chamber (12), resulting in a dashpot effect. However, since the spring force is large, the throttle valve (10) does not close easily, and the measurement time is longer than the normal time. Conversely, if the spring constant is smaller than the predetermined set value, the throttle valve (10) will close immediately, and the measurement time will be shortened.

In the dashpot control device having the above configuration, when the measurement time is longer than the predetermined time, the predetermined degree correction means (16) reduces the predetermined opening degree to delay the start of the dashpot action; Further, if the measured time is shorter than the predetermined time, the predetermined opening degree correction means (16) increases the predetermined opening degree, thereby making it possible to bring the time at which the dashpot action starts earlier.

Thereby, the time period during which the dashpot action is applied to the throttle valve (10) can be made constant, and the operation can be stabilized.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings. Second
The figure is a configuration diagram of the main parts of the dashpot control I device f17, which is an embodiment of the present invention. Components corresponding to those shown in FIG. 1 are given the same reference numerals.

In the figure, reference numeral 10 denotes a throttle valve which rotates in conjunction with the operation of an accelerator pedal (not shown) and controls the amount of intake air flowing through the intake manifold 18. The opening degree (TA) of this throttle valve 10 is configured to be detected by a linear throttle position sensor 19, and a throttle position sensor signal (IDL) output from this sensor 19 is sent to an engine control unit (ECLI) 20, which will be described later. sent to.

Further, the throttle valve 10 is connected to a dashpot 11. The dashbot 11 is divided into two chambers by a diaphragm 21, and a coil spring 13 is disposed within the diaphragm chamber 12 to which negative pressure is applied. By applying negative pressure within the diaphragm chamber 12, the diaphragm 21 is displaced according to the difference between this negative pressure and the spring force of the coil spring 13, and the rod 22 moves in accordance with this displacement as indicated by the arrows B+ and 82 in the figure. Displace in the direction.

In particular, when the rod 22 is displaced in the B2 direction, a dashpot effect is applied to the throttle valve 10.

The dashbot 11 is connected to a negative pressure delay valve (hereinafter referred to as VTV) 23 via a pipe 24. This VT
The V23 functions to gradually apply negative pressure to the dashbot 11 when negative pressure is applied to the dashbot 11 as will be described later, and this VTV23 causes the throttle valve 10 to be activated when the dashpot is activated. The valve is configured to gradually close. In addition, this VTV 23 is connected to a negative pressure switching valve (hereinafter referred to as VsV) via piping 25.
26. VSV26 is a three-way switching solenoid valve, and selectively connects two of the three connected pipes 25°27.28 based on a drive signal supplied from ECLJ20. In the following explanation, VSV26
When the piping 25 and the piping 27 are connected to each other (in the figure,
When connected as shown by the solid arrow), the VSV26
is said to be in the on (ON) state, and when the piping 25 and the piping 28 are communicated by the VSV 26 (as indicated by the dashed arrow in the figure), the vsV 26 is said to be in the OFF (ON) state.
This state is called OFF). Also, the above-mentioned VTV23.
VSV26. The pipes 24, 25, 27, 28 together constitute the dashpot drive.

The piping 27 has one end connected to the VSV 26 described above, and the other end opened at a position upstream of the throttle valve 10 of the intake manifold 18.

Further, one end of the pipe 28 is connected to the VSV 26, and the other end is opened at a position on the downstream side of the throttle valve 10 of the intake manifold 18. In FIG. 2, it is assumed that the intake air flows from the cloth to the left.

Now, considering the state where the throttle valve 10 is closed to near the idle position, the throttle valve 1 of the intake manifold 18
The upstream side of the throttle valve 10 is at atmospheric pressure, while the downstream side of the throttle valve 10 is at negative pressure. Therefore, if ■S■26 is turned OFF in this state, the pipe 28.
VSV26° piping 25. Negative pressure in the intake manifold 18 is applied to the diaphragm chamber 12 via the VTV 23, the rod 22 is displaced in the B2 direction, and the throttle valve 10 is gradually closed by the dashpot action of the dashpot 11.

On the other hand, when the VSV 26 is turned on, the atmospheric pressure changes to the pipe 27.
VSV26. Piping 25. VTV23. The rod 22 is introduced into the diaphragm chamber 12 via the pipe 24, and the rod 22 is displaced in the B2 direction, so that the throttle valve 10 is in a state of rotation in response to the operation of the accelerator pedal.

As described above, the dashpot action is applied to the throttle valve 10 by turning the VSV 26 ON and OFF. The ECU 20 also includes a throttle valve 1 suitable for producing a preset dashpot action.
An opening degree of 0 (hereinafter, this opening degree is referred to as a default opening degree, and is indicated by the symbol TAOFF+8) is stored. ECU20
calculates the opening degree (TA) of the throttle valve 10 based on the IDL signal from the throttle position meter 19, and when this opening degree TA becomes less than the predetermined opening degree (TAOFF+8),
The configuration is such that the dashbot 11 applies a dashpot effect to the throttle valve 10 by turning off the VSV 26.

The above description is about the operation during deceleration, but during acceleration, the opening TA of the throttle valve 10 is equal to the predetermined opening (TAO).
N+S) or more, the VSV 26 is turned on and the dashpot action is stopped.

The ECU 20 is a central control circuit (CPU) 29. Random Access Memory (RAM) 30. Read-only memory (R
OM)31. Backup random access memory (B
-RAM) 32. Of these, ROM31
Stored are programs such as a main routine, a fuel injection amount control routine, and a dashpot control routine that is a feature of the present invention, as well as various maps, fixed data, constants, etc. necessary for these processes. Also ECtJ20
An A/D conversion circuit 33 having a multiplexer and an I10 device 34 having a buffer memory are incorporated, and the circuits 29 to 34 are connected to each other by a common bus 35. Various sensors and devices necessary for engine control are connected to this A/D conversion circuit 33 and I10 device 34, but for convenience of explanation, the throttle position sensor 19 and ■s necessary for dashpot control are shown in FIG.
(2) Only the structure in which 26 is connected is shown.

The CPtJ 29 performs engine control according to a program stored in the ROM 31 and based on detection data output from various sensors, and also performs dashpot control processing based on a program described below.

FIG. 3 shows a dashpot l1l which is an embodiment of the present invention.
It is a flowchart of IIl processing. This routine is executed every 4ss, for example.

When this routine is started, CPLI first performs step 1.
00, the opening degree TA of the throttle valve 10 is determined based on the IDL signal supplied from the throttle position sensor 19.
is determined, and it is determined whether this opening degree TA is larger than a predetermined opening degree (TAON+8) that stops the dashpot action during acceleration.

If the opening degree TA is larger than the predetermined opening degree (TAON+8), there is no need to perform the dashpot action, so in step 110 the VSV 26 is turned on and the process ends.

On the other hand, if a negative determination is made in step 100, the process proceeds to step 120, where the opening degree TA of the throttle valve 10 is
is the predetermined opening degree (TAOF) that starts the dashpot action.
F+S). In step 120, the above opening degree TA is the default opening degree (TAOFF+S)
If it is determined that this has not been reached, the process ends because there is no need to perform the dashpot action.

If an affirmative determination is made in step 120, the throttle valve 10 is opened at a predetermined opening T to provide a dashpot effect.
AOFF+S has been reached, so the VSV 26 is turned off in step 130, and the negative pressure in the intake manifold 18 is applied to the diaphragm chamber 12 via the pipes 28, 25, 24, etc. As a result, Dashbot 11
The dashpot effect on the throttle valve 10 begins, and the throttle valve 10 gradually closes.

In the following step 140, it is determined whether the VSV 26 was turned on last time. If an affirmative determination is made in step 140, this state is immediately after the VSV 26 has been turned off, and at this time, in step 150, a counter (CDP) for measuring time is initialized. On the other hand, if a negative determination is made in step 140, the process in step 150 is bypassed and the process proceeds to steps 160 and subsequent steps. Therefore, counter CDP is set when VSV26 is OF.
Counting will continue starting from the time the switch is made to F.

In step 160, it is determined whether the opening degree TA of the throttle valve 10 is "0" for the first time, that is, it is fully open.

A state in which a negative determination is made in step 160 is a state in which the throttle valve 10 is in the process of reaching a fully open state from the predetermined opening degree TAOFF+S, or a state in which the throttle valve 10 is opened and closed again after reaching a fully closed state. . At this time, the process ends.

If an affirmative determination is made in step 160, the process proceeds to step 17.
0, and the value counted by the counter CDP (hereinafter referred to as C
DP) is between 0.9 seconds and 1.1 seconds. In this example, CDP
It is assumed that the coil spring 13 is in a normal state when 0.9≦CDP≦1.1. The value of this CDP is the time it takes for the throttle valve 10 to reach the fully open state from the predetermined opening degree TAOFF+S, in other words, the throttle valve 1
This is the time during which the dashpot effect is operating at 0.

If this CDP is shorter than 0.9 seconds, the coil spring 13 has become fatigued or the spring constant is smaller than a predetermined value, and if the CDP is longer than 1.1 seconds, the coil spring 13 This is a case where the spring constant of is larger than a predetermined value.

As described above, when the CDP is longer or shorter than the predetermined time (0.9 seconds to 1.1 seconds), emissions and fuel efficiency deteriorate.

Therefore, if the value of CDP is shorter than the lower limit of the predetermined value (0.9 seconds), in step 180 the correction value S is adjusted to an angle of 0.9 seconds.
If the value of CDP is longer than the upper limit of the predetermined value (1.1 seconds), the correction value S is decreased by an angle of 0.5 deg in step 190, and furthermore, the CDP is within the predetermined value (1.1 seconds). 0.9 seconds to 1.1 seconds), no correction is applied to the correction value S.

With this configuration, the time period during which the dashpot operation is applied to the throttle valve 10 can be made constant, thereby realizing stable engine operation. Note that step 180. The correction value S updated in step 190 is
00. 120. Therefore, by changing the correction i1S, the predetermined opening degree of the throttle valve 10 at which the VSV 26 is turned on and the predetermined opening degree at which the dashpot action starts are corrected.

The reason why the time during which the dashpot effect is activated can be made constant by updating the correction value S based on the value of CDP as described above will be explained with reference to FIG. still,
In the following explanation, correction will be explained when the CDP becomes longer than the upper limit of the predetermined value. Furthermore, since the basic idea is the same regarding correction when the CDP is shorter than the lower limit of the predetermined value, the explanation thereof will be omitted.

In the same figure, (A) indicates the opening degree TA of the throttle valve 10,
(B) shows VsV26 (7) ON and OFF states, (C)
indicate CDP, respectively.

Now, assuming that the coil spring 13 installed inside the dashpot 11 is normal, the throttle valve 10
V when Baidu TA reaches the default Baidu TAOFF+S
When the SV26 is turned OFF, the dashpot action is activated, so that the valve closing speed of the opening degree TA is slowed down, and the throttle valve 10 is fully closed within 0.9 seconds to 1.1 seconds after the VSV 26 is turned OFF. Changes in the opening degree of the throttle valve 10 in this normal state are as shown by the solid line in FIG. 4(A).

On the other hand, when the spring constant of the coil spring 13 is larger than the predetermined value, the closing speed of the throttle valve 10 becomes slower than in the normal state, and the throttle valve 10
The change in the opening degree is shown by the two-dot chain line in Fig. 4 (A). Therefore, when the time from when the VSV 26 turns OFF and the dashpot action starts until the throttle valve 10 is fully closed is longer than the upper limit of the predetermined time. II j 1 is required.

In the above case, step 190 (see Figure 3)
The correction value S is set low. This means lowering the default opening degree TAOFF+S on the vertical axis in Figure 4 (A), and the default opening degree is shown in the figure (TAOFF+81
), even if the spring constant of the coil spring 13 is different from the normal value, the time period during which the dashpot action is activated can be set to a predetermined time (0.9 seconds to 1.1 seconds). At this time, the timing at which the VSV 26 turns OFF is the hour If To. In this manner, by correcting the correction value S in accordance with the measurement time CDP in step 190, the time during which the dashpot effect is working can be set as a predetermined time. Note that the process of step 180 is to correct TAOFF+S upward along the vertical axis in FIG. The working time of the worker can be corrected to a predetermined time.

The explanation will be given by returning to FIG. 3 again. Steps 170-190
When the correction value S is updated in step 20, the process proceeds to step 20.
The process proceeds to step 210, and it is determined whether the correction value S is within O to 3 deQ. If it is not within this range, the process proceeds to step 210, and the correction value S is set to O or 3 deg. Step 200. In the process of 210, the correction value S takes an extreme value,
On the contrary, it is provided to prevent the operation of the engine from becoming unstable. Note that if an affirmative determination is made in step 200, the process ends.

〔Effect of the invention〕

As described above, according to the present invention, since the time during which the dashpot action is applied to the throttle valve can be made constant, deterioration in emissions and fuel efficiency can be prevented, and engine operation can be stabilized, among other features. .

[Brief explanation of drawings]

FIG. 1 is a diagram of the principle of the present invention, FIG. 2 is a diagram showing the main part of a dashpot l1lIll installation which is an embodiment of the present invention, and FIG. 3 is a flowchart showing dashpot control processing.
FIG. 4 is a diagram for explaining the present invention in detail, and FIG. 5 is a diagram showing an example of a conventional dashpot control device. 10... Throttle valve, 11... Dashpot,
12... Diaphragm chamber, 13... Spring means (coil spring), 17... Dashpot control, 19
...Linear throttle position sensor, 21...
Diaphragm, 23...VTV (negative pressure delay valve), 2
6...VSV (negative pressure switching valve). Figure 1 Figure 2

Claims (1)

[Scope of Claims] When the throttle valve reaches a preset opening degree, negative pressure is introduced into the diaphragm chamber of the dashpot, and the throttle valve is opened against the biasing force of a spring means installed in the diaphragm chamber. In a dashpot control device comprising a dashpot driving means that provides a dashpot effect, the throttle valve changes from a first opening degree to a lower opening degree than the first opening degree by applying negative pressure to the diaphragm chamber. a measuring means for measuring the time until the second opening degree is reached; and when the time measured by the measuring means is longer than a preset predetermined time, the predetermined opening degree is corrected to be smaller;
A dashpot control device comprising: a predetermined opening degree correction means that corrects the predetermined opening degree to be larger when the measured time is shorter than a preset predetermined time period.