JPH0257701A - Cylinder stroke controller - Google Patents

Abstract

PURPOSE:To accurately and rapidly carry out the setting of a cylinder at a desired position, by carrying out the control of cylinder strokes by using its anticipated stroke position which reflects its actual stroke position through a signal from its position detector. CONSTITUTION:An electronic controller 4 receives the signals from a vehicle speed sensor 41 for detecting the running speed of a vehicle, a steering angle sensor 42 for detecting its steering angle, a position detecting sensor 43 for detecting that the stroke position of a cylinder device 16 reaches a predetermined location, and then anticipates the position of expansion of the cylinder device 16 according to the signals transferred from the speed sensor 41 and the steering angle sensor 42, and then corrects the position anticipated of its expansion according to the signal from the position detecting sensor 43, thereby setting the cylinder device 16 at this anticipated expansion position. The control of the cylinfer stroke is thus enabled by open-loop control, so that the stroke position of the cylinder device 16 can be accurately as well as rapidly set to its aimed position.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a cylinder stroke control device that controls the expansion/contraction position (stroke position) of a cylinder device, and is effective for use in, for example, a cylinder device that adjusts the torsional force of a stabilizer. be.

[Conventional technology]

BACKGROUND ART Conventionally, it has been known, for example, in Japanese Patent Application Laid-Open No. 146612/1983, that the attitude of a vehicle is controlled using a hydraulic cylinder operated by hydraulic pressure in a stabilizer.

This calculates the control amount of the hydraulic cylinder in order to suppress the lateral tilt (roll) of the vehicle body that occurs when the vehicle turns, and the hydraulic cylinder is controlled to extend or contract based on this control amount.

At this time, as a sensor for detecting the length (stroke) of the hydraulic cylinder, one of the fixed end and the flexible potentiometer of the potentiometer is fixed to one end of the stabilizer, and the other is fixed to the unsprung member, so that the sensor detects the length (stroke) of the hydraulic cylinder. The electrical signal is extracted from the potentiometer.

[Problems to be Solved by the Invention] However, in the conventional example, a target control amount of the cylinder device is calculated according to the running condition, and the target stroke position based on this target control amount and the actual stroke position detected by the sensor are Feedback control is performed based on the deviation of However, when controlling the stroke position of a cylinder device using a pressure fluid such as pressure oil, a certain amount of response delay occurs from when a command to start control is given until the cylinder device is actually driven. In the conventional example, since feedback control is performed, a predetermined amount of time is required for calculations and the like before the cylinder device is driven. As described above, in the conventional example, there is not only a response delay when driving the cylinder device but also a control delay due to feedback control, which may make the occupant feel uncomfortable in the vehicle behavior.

Furthermore, in the conventional example, a sensor for detecting the length of the cylinder device is installed between the stabilizer and the unsprung member separately from the cylinder device, which makes the configuration complicated. It also becomes complicated and expensive.

The present invention has been made in view of the above points, and uses a sensor with a simple configuration that detects only when the stroke position of the cylinder device has reached a predetermined position, so that the stroke position can accurately and quickly reach the target position. The object of the present invention is to provide a cylinder stroke control device that can control the cylinder stroke.

[Means to solve the problem]

In order to achieve the above object, the cylinder stroke control device according to the present invention, as shown in FIG. a prediction means for predicting the extension/retraction position of the cylinder device based on a control signal; a predetermined position detection means for detecting that the actual extension/retraction position of the cylinder device has reached a predetermined position; and a predetermined position detection means. correction means for correcting the extension/retraction position of the cylinder device predicted by the prediction means, based on a signal from the predetermined position detection means, when it is detected that the extension/retraction position of the cylinder device has reached a predetermined position; The apparatus further includes a control means for outputting a control signal to the adjustment means in order to make the predicted expansion/contraction position of the cylinder and cylinder device corrected by the correction means coincide with a target position.

[Effect]

In the above configuration, since the predetermined position detection means detects only that the stroke position of the cylinder device has reached the predetermined position, its structure can be simplified.

Further, when it is detected that the stroke position of the cylinder device has reached a predetermined position, the correction means corrects the predicted stroke position of the cylinder device predicted by the prediction means. Therefore, the actual stroke position of the cylinder device can be accurately predicted. In the present invention, control is performed based on the target stroke position and the predicted stroke position, except when the predicted stroke position is corrected by the correction means as described above. In this way, since the cylinder stroke control is performed by so-called open-loop control, control delays can be reduced.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 2 is a configuration diagram showing the overall configuration of a vehicle attitude control device to which a cylinder device 16 including a cylinder stroke control device according to the present invention is applied.

In FIG. 2, the vehicle attitude control system includes a front wheel stabilizer system 2, a hydraulic system 3, and an electronic control system 4 that controls these.

In the front wheel side stabilizer device 2, the left and right front wheels 6,1
0 is a vehicle body 9 with left and right front wheel shock absorbers 7.11 and left and right front wheel suspension arms 8.12, respectively.
is supported by Furthermore, the front wheel side stabilizer bar 1
The torsion portion 3 is rotatably supported by the vehicle body 9 by a bearing fixed to the vehicle body 9 with a bolt or the like. One end portion 13a of the front wheel stabilizer bar 13 is coupled to a sprung portion of the right front wheel shock absorber 11 via a cylinder device 16 whose connection distance can be adjusted.

The other end portion 13b of the front wheel stabilizer bar 13 is attached to a sprung portion of the left front wheel shock absorber 7 via a link rod 17. In addition, 19 is the left and right front wheels 6.1 depending on the operation of the steering wheel (not shown).
This is a steering mechanism that changes the direction of zero.

The electronic control device 4 includes a vehicle speed sensor 41 that detects the traveling speed of the vehicle. Signals from a steering angle sensor 42 that detects the steering angle and a position detection device 43 that detects that the stroke position of the cylinder device 16 has reached a predetermined position are input, and a control signal is output to the hydraulic device 3.

Here, the structure of the cylinder device 16 will be explained. The cylinder device 16 includes a cylinder body 2 as shown in FIG.
1 is divided into an upper chamber 25 and a lower chamber 26 by a piston 22 slidably disposed within the upper chamber 25. In the lower chamber 26, the upper chamber port 23. Pressure oil is supplied and discharged from the lower chamber boat 24. Further, a rod 27 is fixed to the piston 22, and a position detection device 43 for detecting a predetermined stroke position of the cylinder device 16 is incorporated in the upper part of the cylinder body 21. The front wheel stabilizer device 2 is configured to change the amount of twist of the front wheel stabilizer bar 13 by expanding and contracting the cylinder device 16, thereby increasing the torsional reaction force and thereby changing the apparent torsional rigidity. There is.

As shown in FIG. 4, the cylinder device 16 is operated by pressure oil supplied from the hydraulic device 3 in response to a control signal from an electronic control bag W4.

In the hydraulic system 3, a hydraulic pump 31 driven by an engine 30 via a power transmission mechanism sucks hydraulic oil from a reservoir tank 34, and operates through a conduit 33a and a control valve (4-point, 3-position solenoid valve) 32. ．． Pressure oil is supplied to the cylinder device 16 via pipes 33c and 33d. The control valve 32 has 1
Consists of two spools and two linear solenoids.
A neutral position 32a that blocks the pipeline between the pump 31 and the cylinder device 16 in response to a control signal from the electronic control device 4.

Pressure oil is supplied to the lower chamber 26 of the cylinder device 16, and the upper chamber 25
It can be switched to three positions: an extended position 32b for discharging pressure oil from the upper chamber 25, a retracted position 32c for supplying pressure oil to the upper chamber 25 and discharging pressure oil from the lower chamber 26, and any intermediate position thereof.

The electronic control device 4 is composed of a microcomputer and the like as shown in FIG. Central processing unit (CPU) 4a
, a read-only memory section (ROM) 4b that stores calculation programs, fixed data, etc., a storage section (RAM) 4 that temporarily stores calculation results, control status, etc. Based on the C1 calculation result, the control valve 32 Output section 4e that outputs a control signal
, and a common bus 4f that interconnects these parts.

To explain the position detection device 43 here, the position detection device 43 can be configured as follows, for example. That is, the piston rod 27 of the cylinder device 16 is constructed by joining a magnetic material and a non-magnetic material, such as iron and stainless steel, for example. Further, a coil is formed in the upper part of the cylinder body 21 by winding a conducting wire so that the piston rod 27 is located at the center. When measuring the inductance of the coil in such a configuration, the inductance of the coil will have a significantly different value depending on whether a magnetic material passes through the coil or a non-magnetic material passes through the coil. Therefore, by connecting a resistor in series with the coil and measuring the time constant of the output response to the pulsed voltage input, measuring the resonant frequency, or measuring the phase difference of the current with respect to the AC voltage input, etc. By measuring the inductance of the coil, a predetermined stroke position of the cylinder device 16 can be detected. Alternatively, the position detection device 43 may be configured by forming the piston rod from a non-magnetic material, embedding a magnetic material in a part thereof, and using a magnetic switch that operates only when the magnetic material is at a predetermined position. In this embodiment, the position detection device 43 is configured to detect the intermediate position of the stroke of the cylinder device 16.

Next, the basic operation and control method in the above configuration will be explained.

When the vehicle is traveling straight ahead, the control valve 32 shown in FIG. 4 is set to the neutral position 32a. At this time, the pressure oil discharged from the hydraulic pump 31 flows through the pipe line 33a.

Control valve 32. It returns to the reservoir 34 via the conduit 33b. On the other hand, since the conduits 33c and 33d are shut off by the control valve 32, the upper and lower chambers 25 and 26 of the cylinder device 16 are maintained in an oil-tight state, and the piston 22 is fixed within the cylinder body 21. That is, the cylinder device 16 functions as a type of body like the link rod 17, and the stabilizer 13 exhibits its inherent torsional rigidity to ensure running stability of the vehicle.

Further, when turning, the target expansion/contraction amount of the cylinder device 16 is determined according to a predetermined relationship depending on the vehicle speed and the magnitude of the steering angle. The hydraulic device 3 is driven to extend or contract the cylinder device 16 according to the target extension 1i1it. That is, when the cylinder device 16 is extended, the control valve 32 is driven toward the extended position i132b, or the near solenoid is energized. At this time, the cylinder device 16
A control valve 32 connected to the lower chamber 26 of the
The port immediately opens fully, and pressure oil from the pump 31 flows through the pipe line 33a and the control valve 32. It is supplied to the lower chamber 26 of the cylinder device 16 via the conduit 33d.

The port of the control valve 32 connected to the upper chamber 25 of the cylinder device 16 via the conduit 33c operates so that its opening area increases with the magnitude of the energizing current. Therefore, by controlling the applied current, the flow rate flowing out through the conduit 33c is adjusted. In other words, the piston 22 can only move in the direction of the upper chamber 25 when pressure oil flows out from the upper chamber 25, so the amount of movement of the piston 22, that is, the amount of expansion and contraction of the cylinder device 16, is adjusted by controlling the current flowing through the linear solenoid. be able to. Moreover, since the relationship between the magnitude of the energizing current and the outflow amount, that is, the amount of movement of the piston can be known in advance, the electronic control device 4 can predict and calculate the position of the piston 22 from the magnitude of the energizing current to be output and the energization time. In this predictive calculation, the predicted position of the piston 22 is corrected using the position detection device 43, and then, when it is determined that the predicted position of the piston 22 has reached the target position, energization to the linear solenoid is terminated. At this time, the control valve 32 returns to the neutral position 32a, the upper and lower chambers 25, 26 of the cylinder device 16 are again maintained in an oil-tight state, and the piston 22 is fixed at the target position. in this way,
Since the hydraulic system 3 has a meter-out hydraulic circuit configuration,
The oil amount can be adjusted accurately from a small amount to a large amount, and the cylinder device 16 can be reliably controlled.

Furthermore, when the cylinder device 16 is contracted, the 1J near solenoid that drives the control valve 32 toward the contracted position 32c is energized. At this time, the port of the control valve 32 connected to the upper chamber 25 of the cylinder device 16 via the pipe line 33c is immediately fully opened, and the pressure oil from the pump 31 flows through the pipe line 33a, the control valve 32. It is supplied to the upper chamber 25 of the cylinder device 16 via the pipe line 33c. On the other hand, the port of the control valve 32 connected to the lower chamber 26 of the cylinder device 16 via the pipe 33d is
It operates so that the opening area increases as the applied current increases. Therefore, by controlling the applied current, the amount of oil flowing out through the conduit 33d is adjusted.

Therefore, the position of the piston 22 is predicted in the same way as when the cylinder device 16 is extended, and when it is determined that the piston 22 has reached the target position, the energization is terminated and the piston 22 is fixed at the target position.

Next, an example of control executed by the cylinder stroke control device that controls the amount of expansion and contraction of the cylinder device 16 (hereinafter referred to as the stroke of the cylinder device) will be described with reference to the flowchart in FIG. Note that the stroke control process shown in FIG. 5 is repeatedly executed at a cycle that is sufficiently faster than the response time of the hydraulic system 3 (for example, 8 m5ec). Therefore, control can be performed to compensate for the response delay of the mechanical system when driving the cylinder device 16.

First, in steps 100 and 110, the vehicle speed V, steering angle θ, and steering direction are read. In step 120, it is determined from these values whether the vehicle is turning or going straight based on a predetermined map. This determination process is performed when the steering angle θ is within the so-called steering uncertainty range, in which the play in the steering system and the steering force are absorbed by the torsion of the steering wheels and do not contribute to steering.
It is determined that the vehicle is traveling straight, and other times it is determined that the vehicle is turning. In addition,
The size of the steering dead zone is larger at lower speeds and becomes smaller as the vehicle speed increases, and is determined from a map stored in advance.

If it is determined in step 120 that the vehicle is turning, the process proceeds to step 130 and calculates the lateral acceleration G (=f-(e, V)).
Calculate. Further, the process proceeds to step 140, where a target stroke position SA of the cylinder device 16 necessary for suppressing the roll of the vehicle body due to the lateral acceleration G not calculated in step 130 is calculated. Meanwhile, step 120
If it is determined that the vehicle is not turning, that is, is traveling straight, the process advances to step 150 and the target stroke position 5T (-
so fg (c), So: neutral stroke position) is set to the neutral position of the cylinder device 16.

In step 160, the target stroke position S obtained in step 140 or 150 is compared with the predicted stroke position SC obtained in the previous calculation. Step 16
0, if it is determined that the target stroke position S7 and the predicted stroke position S are not equal, step 1
Proceed to 70.

In step 170, the value of the current I to be applied to the linear solenoid of the control valve 32 is calculated according to the magnitude and sign of the difference between the target stroke position S7 and the predicted stroke position S. On the other hand, if it is determined that the target stroke position SA and the predicted stroke position SC are equal, the process proceeds to step 180 and the current I applied to the linear solenoid is set to zero.

In step 190, the linear solenoid of the control valve 32 is energized based on the value of the current I determined in steps 170 and 180°.

In step 200, the predicted stroke position Sc of the cylinder system [16] is determined from the value of the current I flowing to the linear solenoid of the control valve 32. That is, the outflow flow rate, that is, the amount of movement of the piston 22 per unit time (time of the calculation cycle) (the cylinder device 16
Since the base area of is known, the amount of movement = height can be determined from the flow rate and volume. ). Piston 22 for each calculation cycle
By integrating the amount of movement, the predicted stroke position Sc of the cylinder device 16 can be determined. Furthermore, in this process, it is known from the signal of the position detection device 43 that the actual stroke position of the cylinder device 16 has passed the neutral position, so every time the actual stroke position passes the neutral position, the predicted stroke position S at that time , is corrected according to the procedure explained later. Furthermore, based on the magnitude of the correction amount of the predicted stroke position Sc at this time, a correction is also made to the value of the energizing current ■ to the linear solenoid of the control valve 32.

The above process is repeatedly executed at regular intervals.

Next, a specific calculation method in the main steps will be explained.

First, the calculation process of the value of the energizing current (2) in steps 160 to 180 will be explained. Step 14 in this calculation cycle
Deviation ER (-3t Sc) between the target stroke position S↑ calculated in the process of 0 and the predicted stroke position S that predicts the current stroke position calculated in the previous process (that is, the calculation before a tssec) seek. If the value of this deviation ER is greater than a predetermined value (if it exceeds the control dead zone), first, the cylinder device I
6. Determine whether to expand or contract. That is, when the sign of the deviation ER is positive, the target stroke position S
Since it is estimated that the actual stroke position is still insufficiently extended with respect to t, it is necessary to extend it, and it can be seen that when the sign of the deviation ER is negative, it is necessary to similarly contract it. In this embodiment, in order to simplify calculation processing, all stroke position values are treated as positive values, the stroke position when the cylinder device 16 is most contracted is the minimum value, and the most extended state is the maximum value. It is said that Next, the deviation ER
From the magnitude (absolute value) of , find the value of the current I required to make the deviation ER zero. This process, for example,
As shown in the figure, it can be determined by a map in which the value of the energizing current (2) increases as the ER increases. In addition,
The origin (10) of the ER axis in Fig. 6 represents the edge of the control zone, and due to the current flowing at this time,
Stroke control of the cylinder device 16 is started by the control valve 32 . Further, the energizing current (■) is the maximum current, and the maximum outflow flow rate can be obtained with this current. Furthermore, when the deviation ERO value is within the control dead zone, it is estimated that the predicted stroke position S and the target stroke position St coincide within the control dead zone, so the solenoid energizing current ■ of the control valve 32 is set to zero. The control valve 32 is switched to the neutral position 111E32a to fix the cylinder device 16 in an oil-tight state.

Next, a method of calculating the predicted stroke position Sc in step 200 will be explained.

First, the steady flow rate Q of the outflow from the cylinder device 16 with respect to the current () applied to the control valve 32 is measured in advance. This measurement is performed when the vehicle is traveling straight and when the vehicle is turning. This is to correct the fluctuation of the outflow flow rate Q from the cylinder device 16 due to a load shift caused by the lateral acceleration G during cornering. As a result of this measurement, the passing current I
An example of this r-Q map is shown in FIG. 7, which is a basic map (hereinafter referred to as a 1-Q map) of the relationship between In Figure 7, the no-load curve is the I-Q curve when traveling straight.
Show characteristics. Further, the positive load curve shows the I-Q characteristic when the cylinder device 16 is driven in a direction that suppresses the roll of the vehicle body, and the reverse load curve shows the I-Q characteristic when the cylinder device 16 is driven in the direction that promotes the roll of the vehicle body. .

Now, in the control valve 32, it can be considered that the value of the energizing current (2) and the position of the spool have a one-to-one correspondence. However, because there is some kind of delay element transiently, even if current ■ is applied to the linear solenoid, the spool immediately
does not move to the corresponding position. Furthermore, even if the spool moves, the pressure due to the pressure oil is not immediately transferred to the cylinder device 16 via the control valve 32. Therefore, these lag elements are approximated by first-order lags, and the value of the energizing current I in the current control at step 190 is regarded as the first-order lag element to obtain the first-order lag current ■8 (process 1).

Next, the predicted stroke position S obtained in the previous calculation cycle,
and the neutral position S of the cylinder device 16. The load amount Load is calculated using the following equation based on the distance from the current control and the expansion/contraction direction of the current control in step 190. Note that the load amount Load here refers to an external force that tries to prevent the cylinder device 16 from expanding or contracting, and generally the load amount Load of the cylinder device 16 is proportional to the amount of expansion or contraction from the neutral position. do.

Load=kz HSc S.

In the above equation, when the previous predicted stroke position Sc is on the extension side of the cylinder device 16 and the current driving direction is the extension direction, the constant 3 takes a positive value, and when it is in the contraction direction, the constant 3 takes a negative value. Takes a value.

In addition, when the previous predicted stroke position S is on the contraction side and the current driving direction is also on the contraction direction, a positive value;
It takes a negative value when it is in the stretching direction.

(Process 2) The primary lag current ■8 obtained in the above processes 1 and 2 and the load amount Lo
Using the map shown in FIG. 7 from the adO value, the flow rate Q flowing out from the cylinder device 16 during one calculation cycle is determined by the current current control. On the other hand, since the inner diameter of the cylinder body 21 and the diameter of the piston rod 27 are known, the stroke amount δSc of the cylinder device 16 during one calculation cycle can be determined from the outflow flow rate Q. Therefore, the current predicted stroke position 5c(n) is calculated from the previous predicted stroke position S c (n-1) and the stroke amount δSc of the cylinder device 16 during the - calculation cycle as S c (n) = Sc (n-1). + δ
S.

It can be calculated by (processing 3).

Using the current predicted stroke position 5c(n) calculated in the above procedure, the value of the energizing current I in the next calculation cycle is determined as described above.

However, with only such open-loop control, the stroke amount δS for each calculation cycle may change due to temperature changes or other disturbances.
When an error occurs in the estimation of , the predicted stroke position S
Since c is integrated, the predicted stroke position Sc may deviate from the actual stroke position as a result. However, the cylinder stroke control device includes a position detection device 43 as means for detecting the actual stroke position. Since the position detection device 43 can detect that the stroke of the cylinder device 16 has passed through the neutral position, it is possible to correct the cumulative error in the predicted stroke position Sc.

Next, the procedure for the correction will be explained. As described above, there is a response delay in driving the cylinder device 16 by the control valve 32. This response delay component includes the time during which the control valve 32 does not react at all even when the electronic control device 4 commands to start control, or the time during which the piston 22 of the cylinder device 16 does not react at all even when the spool of the control valve 32 moves. There is response dead time such as the time when the response is not completed, and the delay element mentioned above. The predicted stroke position S indicates the stroke position when the cylinder device is driven with this dead response time set to zero. That is, the predicted stroke position S represents a position that will be in the future by the dead response time compared to the actual stroke position. Therefore, the cylinder device 1 is detected by the position detection device 43.
The actual stroke position of No. 6 is the neutral position S. Even if it is detected that the predicted stroke position S at that time is
at neutral position S. It cannot be done.

Therefore, the following processing is performed based on the time relationship between the predicted stroke position Sc and the neutral position detection signal from the position detection device 43. In addition, in this explanation, cylinder device 1
The case where the stroke position of No. 6 is driven from the contraction side to the extension side will be described based on the waveform diagrams in Figs. It is. In addition, the cylinder device 16
The dead response time when driving is called TL.

In the flowchart of FIG. 12, the predicted stroke position S is the neutral position S in step 201.

The neutral position S is determined. If so, proceed to step 202 and set the Sc neutral passing flag. In step 203, the stroke amount δSc for one calculation cycle of stroke control is calculated from the current response dead time T.
The integrated value DSc is calculated by integrating up to before L.

In step 204, the predicted stroke position S is determined.

It is determined whether or not the Sc neutral passing flag indicating that has passed through the neutral position S0 is set. If affirmative (Y), the process proceeds to step 205; if negative (N), the process proceeds to step 211. In step 205, a counter t is incremented, and this counter t means the elapsed time since the predicted stroke position S became neutral. That is, as mentioned above, since the stroke control in this embodiment is repeatedly executed at a cycle of, for example, 8 m5ec, adding 1 to the counter t means that 8 m5ec has elapsed.

In step 206, it is determined whether or not a correction flag indicating that the predicted stroke position Sc is being corrected is set.

Here, as shown in FIG. 8, if the neutral detection signal from the position detection device 43 rises at time Tll after the response dead time TL has elapsed from the time TA when the predicted stroke position Sc became neutral, <0→l>, The predicted stroke position Sc is accurate and does not require correction. However, as shown in FIG.
), if the actual stroke position SA does not reach neutral, it is necessary to correct the predicted stroke position Sc,
This period (T, to Tc) is called a correction period.

When the determination result in step 206 is negative (N), the process proceeds to step 207, where it is determined based on the signal from the position detection device 43 whether the actual stroke position SA has become neutral. When the determination result in step 207 is affirmative (Y), the process proceeds to step 208, where the elapsed time of the counter t and the dead response time TL are compared. As a result of this comparison, if the elapsed time of the counter L and the response dead time T are equal, the predicted stroke position S
Since c does not require correction, the process proceeds to step 209, where the counter t is returned to O, and the Sc neutral progress flag is reset at step 210, and the processing of this routine ends.

On the other hand, as shown in FIG. 9, if the actual stroke position SA does not reach neutral at the time (T,) after the response dead time TL has elapsed from the time ('rA) at which the predicted stroke position S becomes neutral, The process proceeds to step 207 and step 220, and at this time, in the comparison at step 220, the counter t
The elapsed time is equal to or greater than the response dead time TL. As a result, the process proceeds to step 221, where a correction flag indicating that the correction period is in progress is set, and in step 222, the neutral position So
The current process is ended with the sum calculated in step 203 (direction D S c added) as the predicted stroke position SC. Therefore, in the next process, step 20
The determination result in step 6 is affirmative (Y), and the process advances to step 215. In step 215, it is determined whether the actual stroke position SA has become neutral, and if it has not reached neutral, the process proceeds to step 219, where the neutral position S0 and the integrated value D S c calculated in step 203 are added. Let this be the predicted stroke position S. Steps 219 and 2
When the actual stroke position SA becomes neutral through the process in step 22, the predicted stroke position Sc becomes the neutral position S0.
The position is corrected to a position advanced by the control output of the response dead time TL on the extension side. And the actual stroke position SA
becomes neutral, the judgment result in step 215 is affirmative (Y
), and the process proceeds to step 216. In step 216, the correction flag set in step 221 is reset, in step 217, the counter t is returned to O, and in step 218, the Sc neutral pass flag is reset, and the process ends. Although it is possible to make the predicted stroke position Sc correspond to the actual stroke position SA through the above processing, the deviation ER between the predicted stroke position S and the target stroke position S7 becomes larger. However, as shown in FIG. 6, as the deviation BR increases, the value of the energizing current I also increases, so the predicted stroke position Sc and the actual stroke position SA quickly follow the target stroke position ST.

Further, as shown in FIG. 10, the response dead time TL has elapsed (TI
l) Before, the actual stroke position SA becomes neutral (
'rc)L, the flowchart of FIG. 12 proceeds to step 208. As a result of the comparison in step 208, the elapsed time of the counter t is smaller than the dead response time TL, and the process proceeds to step 212. Step 21
In step 2, the elapsed time t is returned to O, and in step 2!3, S
C The neutral passing flag is reset. and step 2
At step 14, the sum of the neutral position So and the integrated value DSc calculated at step 203 is set as the predicted stroke-first position Sc, and the current process ends. Furthermore, as shown in FIG. 11, the actual stroke position SA became neutral before the predicted stroke position Sc reached neutral (
Tc), step 204. Step 211. Step 212, Step 213. Proceed to step 214.

In this way, even if the actual stroke position SA becomes neutral earlier than the scheduled time TA at which the predicted stroke position S becomes neutral, the predicted stroke position S becomes neutral at the time (Tc) when the actual stroke position SA becomes neutral. The predicted stroke position Sc is the neutral position S. The position is corrected to a position advanced by the control output of the response dead time TL on the extension side. Through this process, the fact that the actual stroke position SA has extended excessively with respect to the target stroke position St and the predicted stroke position S is reflected in the predicted stroke position SC. In other words, by this process, the deviation ER between the three target stroke positions and the predicted stroke position S becomes extremely small, or the sign is reversed, so the value of the energizing current ■ decreases, or the cylinder device 16 is oriented in the opposite direction. A current I is applied so as to drive the motor. Therefore, the predicted stroke position Sc and the actual stroke position SA reliably follow the target stroke position St.

Note that in step 208 of the flowchart in FIG. 12, only the case where the elapsed time of the counter t is less than or equal to the response dead time TL is considered; however, in the comparison in step 208, the elapsed time is less than the response dead time TL. This is because it is impossible for the size to become too large. Furthermore, in this embodiment, since control is performed using a predicted stroke position S that predicts the future position of the actual stroke position SA, it is possible to predict in advance how the actual stroke position SA will change. can be recognized. Therefore, if the predicted stroke position Se is not appropriate, the predicted stroke position Sc is corrected before the actual stroke position S reaches that position, so that stable control can be performed with a quick response.

In addition, in this embodiment, the control valve 32 is a spool valve mainly composed of one spool and two linear solenoids, but as described above, the direction of expansion and contraction of the cylinder device can be switched, and the electric Any configuration may be used as long as the means can control the flow rate of the cylinder device. However, the configuration of the output section 4e of the electronic control device 4, the I-Q map shown in FIG. 7, etc. shall be changed as appropriate depending on the specifications of the control valve used.

In addition, even when controlling by current as in the case of the linear solenoid in this embodiment, it is possible to eliminate temperature fluctuations in the solenoid (by placing it in a constant temperature oven, etc.) and to stabilize the power supply voltage. The output section 4e of the computer simply connects the power transistor to 0N at the output port of the computer.
- It may also be configured to be driven in the OFF state. At this time, the voltage applied to the solenoid is controlled ON-OFF with a duty ratio proportional to the required current, thereby controlling the average current value flowing through the solenoid.

Further, in this embodiment, the oil pressure source is simply a pump driven by the engine, but the power steering device and the pump may also be used in common.

Furthermore, in this embodiment, the cylinder device is installed only on the stabilizer installed on the front wheel side, but similar cylinder devices are installed on the stabilizers of the front and rear wheels, respectively.
The same expansion/contraction control as in this embodiment may be performed. In that case,
You can prepare two similar control valves and control the front and rear wheels independently, or you can separate the output port of one control valve and supply it to the two cylinder devices. It may be configured as follows.

In addition, in FIG. 1, the hydraulic device 3 corresponds to the adjustment means, step 200 in the flowchart in FIG. 5 corresponds to the prediction means, the flowchart in FIG. 12 corresponds to the correction means, and the electronic control device 4 corresponds to the control means. It corresponds to the means.

〔Effect of the invention〕

As described above, according to the present invention, the cylinder stroke is controlled by open-loop control, and the predicted stroke position that reflects the actual stroke position is used in the control using the signal from the position detection device. The stroke position of the device can be accurately and quickly reached to the target position.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an overview of the present invention, FIG. 2 is an overall block diagram of a vehicle attitude control device to which a cylinder device equipped with a cylinder stroke control device according to the present invention is applied, and FIG. A cross-sectional view of the cylinder device, Figure 4 is the third
A configuration diagram of an electronic control device and a hydraulic circuit that control the cylinder device shown in the figure, FIG. 5 is a flowchart showing an example of control executed by the electronic control device of FIG. 4, and FIG. 6 is a target stroke position and predicted stroke position. Fig. 7 is a characteristic diagram showing an example of the relationship between the deviation from the energizing current and the energizing current. Fig. 7 is a characteristic diagram showing an example of the relationship between the energizing current and the outflow flow rate for each load. Figs. FIG. 12, which is an explanatory diagram for explaining the correction procedure, is a flowchart as an example for realizing the correction process of the predicted stroke position. 3... Hydraulic circuit, 4... Electronic control device, 16...
Cylinder device, 32... control valve, 43... position detection device.

Claims (1)

[Scope of Claims] Adjustment means for adjusting the extension/retraction position of the cylinder device using pressure fluid in response to an external control signal; and prediction means for predicting the extension/retraction position of the cylinder device based on the external control signal. , a predetermined position detection means for detecting that the actual extension/retraction position of the cylinder device has reached a predetermined position; and a predetermined position detection means detecting that the extension/retraction position of the cylinder device has reached the predetermined position. a correction means for correcting the extension/contraction position of the cylinder device predicted by the prediction means based on a signal from the predetermined position detection means; A cylinder stroke control device comprising: control means for outputting a control signal to the adjustment means so as to match the position.