KR100222766B1 - Suspension control apparatus - Google Patents

Abstract

During an ignition off in which the damping force control of the damping force variable shock absorber is not performed, when disturbances that cause stepping are inputted to the step motor as the actuator for damping force control, an initializing operation is executed quickly at the next ignition so that proper damping force control is performed. Let's make it a task.

41RR)에 탈조를 초래하는 소정의 가속도 입력으로 이루어지는 외관이 입력되어 가속도 스위치(53)가 닫히게 되고, 상기 마이크로컴퓨터(56)에 전력이 공급되면 외관 입력 플래그G_IN을 "1"에 세트해두고, 다음에 이그니션 스위치가 온으로 되어 상기 외란 입력 플래그 G_IN이 "1"의 세트상태 일 때에는 신속하게 이니셜라이즈 처리를 실행한다.Means for solving this are as follows. An acceleration switch 53 is installed between the battery + B and the microcomputer 56 of the control unit 4, so that the step motor 41FL is provided.

41RR) is inputted with an external appearance consisting of a predetermined acceleration input to cause outage, and the acceleration switch 53 is closed. When power is supplied to the microcomputer 56, the external input flag G _IN is set to "1". Next, when the ignition switch is turned on and the disturbance input flag G _IN is set to " 1 ", the initializing process is executed quickly.

Description

Suspension Control

The present invention relates to a semi-active suspension control apparatus for controlling the damping force of the damping force variable shock absorber in multiple stages based on the vertical displacement speed of the vehicle body.

As a conventional semi-active suspension control apparatus, there exist some which are described in Unexamined-Japanese-Patent No. 7-329532 previously proposed by this applicant. In brief description of the damping force variable shock absorber used in the suspension control device, an actuator comprising a step motor is open-controlled in accordance with the up-and-down speed of the spring, which is a control input, for the piston built in each shock absorber. When the valve body is rotated or moved relatively, the opening area between the piston valve body to the fluid side extending between the stretching fluid formed between the piston and the valve body and each fluid interposed as an orifice to the pressure fluid is changed. By changing and controlling the control amount to the actuator, the throttle (flow resistance) of the variable orifice is changed, so that the stretching side and the pressing side damping force can be continuously changed and controlled separately.

The suspension control apparatus described in the above publication further includes the steps of the step motor such that abnormal noises generated when the open-controlled step motor is controlled at the origin of control (hereinafter, also referred to as initialization) are masked by load noise or the like. Initialization is performed when the vehicle speed reaches a predetermined value or more. In addition, in consideration of the fact that the initializing of the stepper motor is actually performed during driving, the suspension control apparatus is configured to perform an excitation input of a predetermined value or more, for example, an up and down acceleration, etc. to the vehicle body during the initializing. Since there is a possibility that the rotational position of the actual stepper motor that is controlled to be open and the rotational position of the stepper motor recognized by the control unit handling the same may occur, the step motor may be initialized again. To run.

By the way, such a conventional suspension control device does not receive a normal power supply when the ignition switch is turned off (hereinafter, simply referred to as ignition off), and the ignition switch is turned on (hereinafter simply referred to as ignition on). Technology only). As a result, the rotational position of the step motor (= valve body) at the last ignition off time is stored on the control unit side constituting the control means until the vehicle speed is equal to or higher than a predetermined value and the initializing is executed. When the ignition is turned on, the rotation position control of the step motor is performed based on the stored rotation position of the step motor. By the way, if there is an input (disturbance) to the vehicle body during the ignition off, such as lifting and lowering of the crew, or deliberately shaking the vehicle body, the fluid passing through the orifice is similar to the problem described in the above publication. May cause the step motor to rotate together with the valve body due to the flow resistance, and thus the fluid force, and the rotational position of the step motor stored on the coast low side and the current rotational position may be shifted at the last ignition off. . Therefore, there is a possibility that the step motor is kept out of step and the proper damping force control cannot be performed until the vehicle speed becomes a predetermined value after the next ignition on and the initialization is executed.

SUMMARY OF THE INVENTION The present invention was developed in view of these various problems, and in the case where step-out of the step motor occurs during ignition switch off, a suspension control is performed to promptly initialize the next ignition on and enable proper damping force control. It is an object to provide a device.

1 is a schematic block diagram showing an example of a suspension control device of the present invention.

FIG. 2 is a sectional front view showing a part of an example of the damping force variable shock absorber employed in the suspension control device of FIG.

3 is an explanatory diagram showing damping force characteristics with respect to the position of the valve body of the damping force variable shock absorber.

4 is an explanatory diagram of a stopper mechanism provided in the damping force variable shock absorber shown in FIG.

5 is an explanatory diagram of wiring of the acceleration switch shown in FIG.

6 is a block diagram showing an example of a controller.

7 is a flowchart showing the arithmetic processing of the initialization (control origin intersection) executed by the controller as one embodiment of the suspension control apparatus of the present invention.

8 is an explanatory diagram of the operation of the initialization (control origin calibration) by the arithmetic processing in FIG.

9 is a flowchart showing the operation processing of initializing (control origin calibration) permission and condition setting control executed by the controller as one embodiment of the suspension control device of the present invention.

* Explanation of symbols for main parts of the drawings

1RR : 차륜 2 : 차체1FL

1RR: Wheel 2: Body

3RR : 감쇠력 가변 쇼크 업소버 4 : 콘트롤러 유니트3FL

3RR: Damping force variable shock absorber 4: Controller unit

8: piston 11: lower half body

12: upper half body 13: extending side oil passage

14 pressure side oil flow path 31 valve body

41RR : 스텝 모터35: piston rod 41FL

41RR: Step Motor

44: protruding abutment 45: stopper plate

51RR : 상하가속도 센서46: stopper mechanism 51FL

51RR: Up and down acceleration sensor

52: vehicle speed sensor 53: acceleration switch

59RR : 모터 구동 회로56: 59FL Micro

59RR: Motor Drive Circuit

In order to solve the above problems, the suspension control device according to claim 1 of the present invention is provided between the vehicle body side member and the wheel side member by rotating the valve body by a step motor driven in accordance with an input control signal, A damping force variable shock absorber capable of setting the damping force in multiple stages by changing the throttle through which the fluid passes, a spring up / down speed detecting means for detecting the spring up / down speed of the vehicle body, and at least the spring detected by the spring up / down speed detecting means Set the target rotational position of the valve body according to the damping force to suppress the change in attitude of the vehicle body based on the up and down speed detection value, and output the control signal to the step motor to move the valve body to the target rotational position And control means for open-loop control, the control means detecting the forward and backward speed of the vehicle. A suspension control apparatus comprising vehicle speed detecting means and control home position correcting means for performing control home position correction of the step motor when at least the vehicle speed detected value detected by the vehicle speed detecting means is equal to or greater than a predetermined value. Disturbance input detecting means for detecting that a predetermined or more disturbance is input to the vehicle body while the ignition switch is turned off, and when the disturbance is input to the vehicle body while the ignition switch is turned off by the disturbance input detecting means, immediately after the ignition switch is turned on. And a control origin correction means at the time of the disturbance input for performing the control origin calibration of the switch motor.

In addition, the suspension control device according to claim 2 of the present invention is characterized in that the disturbance input detecting means comprises an acceleration switch which is closed when a predetermined or more acceleration is input to the vehicle body.

[Embodiment of the Invention]

Thus, the suspension device according to claim 1 of the present invention uses, for example, an acceleration switch described in the suspension device according to claim 2 of the present invention, and the control unit side which constitutes a battery which uses this as a power source and the control means. Disturbance input detection means is constituted by remodeling between the and the like. If there is a disturbance input consisting of a predetermined or more acceleration input such as lifting and lowering of the crew or deliberately rocking the vehicle during the ignition off, for example, the acceleration switch is closed so that power is supplied to the control unit. This is stored in the storage device of the control unit, which is part of the disturbance input detection means. In the disturbance input, the control home position correcting means corrects the control origin of the step motor at the same time as or immediately after the ignition switch is turned on only when the disturbance is input to the disturbance input detecting means while the ignition switch is turned off. By removing the step motor, the step motor, which remains until the vehicle speed reaches a predetermined value, can be eliminated as soon as possible, and appropriate damping force control can be started early by the damping force variable shock absorber.

EXAMPLE

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of the suspension control apparatus of this invention is described based on drawing.

1RR)과 차체(2)와의 사이에 각각 서스펜션 장치를 구성하는 감쇠력 가변 쇼크 업소버(3FL

3RR)가 배치되고, 이들 감쇠력 가변 쇼크업소버(3FL

3RR)의 감쇠력을 전환하는 스텝 모터(41FL

41RR)가 후술하는 콘트롤 유니트(4)로부터의 제어신호에 의해 제어된다.1 is a schematic configuration diagram showing an embodiment of the present invention, wherein each wheel 1FL

A damping force variable shock absorber (3FL) constituting a suspension device between 1RR and the vehicle body 2, respectively.

3RR), these damping force variable shock absorbers (3FL)

Step motor 41FL to switch the damping force of 3RR

41RR) is controlled by a control signal from the control unit 4 described later.

3RR)는, 제2도에 도시하듯이, 외통(外筒)(5)가 내통(內筒)(6)으로 구성되는 실린더 튜브(7)를 갖는 트윈 튜브식 가스입 스트러트(strut)형으로 구성되고, 내통(6)내가 이것에 미끄럼접촉하는 피스톤(8)에 의해 상하압력실(9U, 9L)로 구획 구성되어 있다. 또한, 상기 피스톤(8)은, 외주면에 내통(6)과 미끄럼접촉하는 시일부재(9)가 몰드되고 또한 내주면에 중심개공(中心開孔)(10)을 갖는 원통형 하부반체(11)와, 이 하부 반체(11)에 내부끼워진 상부 반체(12)로 구성되어 있다. 이 감쇠력 가변 쇼크업소버(3FL

3RR)의 기본적 구성 및 작용은, 본출원인이 먼저 제안한 상기 특개평7-329532호 공보에 기재되어 있는 것과 동일하거나 거의 동일하므로, 그 상세한 내용에 대해서는 상기 공보를 참조한 것으로 하고, 여기서는 그 상세한 설명을 생략한다. 즉, 제2도중의 도면부호 13는 연신측 오일유로이고, 14는 구멍부이며, 27은 가압측 오일 유로이고, 31은 밸브체이며, 35는 피스톤 로드이고, 36은 차체측 부재이며, 37은 브래킷, 38U, 38L은 고무 부시, 39는 너트, 40은 브래킷, 41a는 회전축, 42는 연결막대, 43은 범퍼 러버이다.Each of these damping forces variable shock absorber (3FL)

As shown in FIG. 2, 3RR is comprised by the twin-tube type gas strut type which has the cylinder tube 7 by which the outer cylinder 5 consists of the inner cylinder 6. As shown in FIG. The inner cylinder 6 is partitioned into upper and lower pressure chambers 9U and 9L by the piston 8 in sliding contact therewith. In addition, the piston (8) is a cylindrical lower half body (11) having a seal member (9) in sliding contact with the inner cylinder (6) on the outer peripheral surface and having a central opening (10) in the inner peripheral surface; It consists of the upper half body 12 embedded in this lower half body 11. This damping force variable shock absorber (3FL

The basic configuration and operation of 3RR) are the same or almost the same as those described in the above-mentioned Japanese Patent Application Laid-Open No. 7-329532, which was first proposed by the present applicant, and therefore, the detailed description thereof is referred to the above publication. Omit. That is, reference numeral 13 in FIG. 2 denotes an extending oil passage, 14 is a hole, 27 is a pressurizing oil passage, 31 is a valve body, 35 is a piston rod, 36 is a vehicle body side member, and 37 Silver brackets, 38U, 38L are rubber bushes, 39 are nuts, 40 are brackets, 41a is a rotating shaft, 42 is a connecting rod and 43 is a bumper rubber.

3RR)의 감쇠력 특성은, 밸브체(31)과 피스톤(8) 사이에 형성되는 각 오리피스의 개구면적에 의해 설정되는 것으로 되고, 이 밸브체(31)를 피스톤(8)에 대해 상대회전시키는 스텝 모터(41FL

41RR)의 회전각은, 상기 오리피스의 교축에 의해 결정되는 유동저항, 즉 감쇠계수를 선택 설정하기 위한 제어량으로 되고, 이 감쇠계수에 상기 피스톤 속도를 곱한 곱의 형태로 각 밸브체 위치에서의 감쇠력이 나타난다. 따라서, 본 실시예의 제어량은 엄밀하게는 감쇠계수이지만, 여기서는 간단히 감쇠력을 제어량으로 생각된다.This damping force variable shock absorber (3FL

The damping force characteristic of 3RR is set by the opening area of each orifice formed between the valve body 31 and the piston 8, and the step of making this valve body 31 rotate relative to the piston 8 is carried out. Motor (41FL

The rotation angle of 41RR) is a control amount for selecting and setting the flow resistance determined by the orifice of the orifice, that is, the damping coefficient, and the damping force at each valve element position in the form of a product of the damping coefficient multiplied by the piston speed. Appears. Therefore, although the control amount of this embodiment is strictly a damping coefficient, the damping force is simply considered as the control amount here.

Therefore, when the rotation angle of this step motor is set to position p, as shown in FIG. 3, the position P where the extending | stretching side damping force becomes the maximum damping force becomes the pressurization side maximum position P _TMAX , and the pressurization side damping force becomes the maximum damping force. The position P becomes the pressurized side maximum position P _CMAX , but for convenience, the position P corresponding to the middle value of the range set to the low damping force of the stretching side damping force and the pressing side damping force is set to " 0 " to increase the stretching side damping force. If the position change in the direction is positive and the position change in the direction of increasing the pressure-side damping force is negative, the stretching side maximum position P _TMAX is simply indicated by a plus sign, P _MAX , and the pressing side maximum position P _CMAX is a minus sign. Simply as (-P _MAX ). However, the absolute value | P _MAX | of these maximum positions does not necessarily have to be the same value. And, of the total damping force control range from the pressurization side maximum position (-P _MAX ) which becomes the said negative value to the stretching side maximum position P _MAX which becomes a positive value, the positive threshold value P which position P puts "0" in between. The range from _T1 to the negative threshold P _C1 ranges from the extension-side decay force D / F _T0 and the pressure-side decay force D / F _C0 , especially in the soft range (hereinafter simply referred to as SS range). In this way, the range where the position P is large in both directions, that is, the position P is the range from the positive threshold value P _T1 to the stretching side maximum position P _MAX of the positive value is set high. Extension side control range (hereinafter also referred to simply as HS range), whereby the position P is in the negative direction, i.e., the position P is the maximum position on the pressing side of the minus value from the negative threshold P _C1 . in the range of up to (-P _MAX), the pressure side damping force The pressure-side control range that is set high (hereinafter, also simply described as SH range). That is, according to the damping force characteristic (damping coefficient characteristic) of FIG. 3, at each predetermined position which achieves the predetermined extending | stretching side damping coefficient which has an equivalent absolute value, and predetermined pressure side attenuation, the absolute value side of a predetermined extending | stretching side position is a predetermined pressure side position value. Slightly smaller than

On the other hand, at the upper end of the valve body 31, a projecting contact body 44 having a rectangular parallelepiped shape as shown in FIG. 4 is protruded, and the valve body by the rotating shaft 41a of the step motor 41FL-41RR ( Rotate synchronously with (31). In the upper half body 12, a stopper plate 45 is built in the inner hole portion of the upper half body 12, and the projecting contact body 44 and the stopper plate 45 are built-in. ) Constitutes the stopper mechanism 46. Two protruding butting protrusions 45a and 45b protrude from the inner hole of the stopper plate 45, and the protrusions protrude in accordance with the rotation of the rotary shaft 41a or the valve body 31 of the stepper motor 41. When the contact body 44 rotates, when the valve body 31 is rotated to the position A or the position C, the two restraining end faces 44a or the restraining end faces 44b of the protruding contact body 44 are rotated. ) Abuts against the protruding butting protrusion 45a or 45b and prevents the valve body 31 from rotating further, so that the position P of the valve body 31 is exactly at the stretching side maximum position P _MAX and the negative value. The so-called limiter, which gives the pressure side maximum position (-P _MAX ), is exerted, but at the same time, the rotation angle of the step motor 41 and the valve body 31 are controlled by the control origin correction process and so-called initializing process described later. The out-of-position correcting effect of a position is also expressed. The detailed structure and operation | movement of this stopper mechanism 46 are explained later in correspondence with the description of the said initializing.

X_RR"을 출력하는 것이다. 또한, 상기 가속도 스위치(53)는 예를 들면 차체중심 위치 또는 그 근방에 설치되고, 차체에 작용하는 (주로 상하방향으로의) 가속도가 소정치 이상일 때에 닫히게 되는 것이며, 예를 들어 후술하듯이 콘트롤 유니트(4)를 구성하는 마이크로 컴퓨터(56)에 대해, 예를 들어 제5도에 도시하듯이 공급전원 (배터리) +B와 마이크로 컴퓨터(56)의 소정의 단자와의 사이에 개장되고, 상기 차체에 작용하는 가속도가 소정치 이상으로 되어 상기 가속도 스위치(53)가 닫히게 되면, 마이크로 컴퓨터(56)에 전력이 공급되도록 하고 있다.Moreover, as shown in FIG. 1, the vehicle has a vehicle speed sensor 52 as a vehicle speed detecting means for detecting the vehicle speed in the forward and backward directions of the car cooling and an acceleration switch 53 as the disturbance input detection means for detecting a disturbance input to the vehicle body. And vertical acceleration sensors 51FL-51RR provided on the vehicle body side corresponding to each of the wheels 1FL-1RR and constituting a part of the spring-like vertical velocity detecting means for detecting the spring-like vertical velocity generated in the vehicle body. Attached. Among these, the output signal V _C of the vehicle speed sensor 52 is composed of a digital value corresponding to the actual vehicle speed value. In addition, each vertical acceleration sensor 51FL-51RR has a spring-like vertical acceleration detection value of an analog voltage value that becomes positive in the upward direction and negative in the downward direction according to the vertical acceleration acting on the vehicle body at each attachment position ( In the following, it is simply described as the vertical acceleration of the spring) X _FR "

X _RR ". The acceleration switch 53 is installed at or near the vehicle center position, for example, and closes when the acceleration (mainly up and down) acting on the vehicle body is greater than or equal to a predetermined value. For example, for the microcomputer 56 constituting the control unit 4 as described later, for example, as shown in FIG. 5, the power supply (battery) + B and predetermined terminals of the microcomputer 56 are shown. When the acceleration switch 53 is closed because the acceleration acting on the vehicle body becomes greater than or equal to a predetermined value, the power is supplied to the microcomputer 56 when the acceleration switch 53 is closed.

X_RR"를 디지털 치로 변환하여 입력 인터페이스 회로(56a)에 공급하는 A/D변환기(57FL-57RR)와, 출력 인터페이스 회로(56b)로부터 출력되는 각 스텝 모터(41FL-41RR)에 대한 스텝 제어신호가 입력되고, 이것을 스텝 펄스로 변환하여 각 스텝 모터(41FL-41RR)를 구동하는 모터 구동회로(59FL-59RR)를 구비하고 있다.The control unit 4 is connected to the input side of the vertical acceleration sensor 51FL-51RR, the vehicle speed sensor 52, and the acceleration switch 53, as shown in FIG. Step motors 41FL-41RR which measure the damping force of each damping force variable shock absorber 3FL-3RR are connected. The control unit 4 includes a microcomputer 56 having at least an input interface circuit 56a, an output interface circuit 56b, an arithmetic processing unit 56c, and a storage unit 56d, and an up / down acceleration sensor 51FL. -51RR) spring up and down acceleration X _FL "

Step control signals for the A / D converters 57FL-57RR for converting X _RR "to digital values and supplying them to the input interface circuit 56a, and for each step motor 41FL-41RR output from the output interface circuit 56b. Is input, and the motor drive circuit 59FL-59RR which converts this into a step pulse and drives each step motor 41FL-41RR is provided.

X_RR"로부터, 예를 들어, 그 시간 적분치로서 상기 차륜부위에서의 차체의 상하속도 (스프링상 상하속도로도 기술) X_FL'

X_RR'를 산출하고, 이들 스프링상 상하속도 X_i'(i=FL

RR)에 대응한 스텝 모터의 목표 회전각, 즉 밸브체의 목표 포지션 P_D를 산출설정하고, 이 목표 포지선 P_D와 현재 포지션 P_A의 차이값을 산출하며, 이것에 따른 스텝 제어량을 모터 구동회로(59FL-59RR)로 출력하고, 상기 스텝모터의 회전각, 즉 밸브체의 포지션에 따른 각 감쇠력 가변 쇼크업소버(3FL-3RR)의 감쇠력을 오픈 루프 제어한다. 한편, 이 감쇠력 가변 쇼크업소버(3FL-3RR)의 감쇠력의 오픈 루프 제어에 대응하여, 상기 스텝 모터의 회전각과 밸브체의 포지션의 탈조를 보정하기 위해, 후술하는 이니셜라이즈 처리의 실행도 취급한다. 이것에 수반하여, 상기 이그니션 오프중에 상기 가속도 스위치(53)가 닫히게 되어 배터러 +B로부터 일시적으로 전력이 공급되면, 도시되지 않은 샘플링 기능 및 홀더 기능 등에 의해, 외란 입력 플래그 G_IN을 "1"로 세트하고, 이것을 상기 기억장치(56d)로 변경 기억해 둔다. 물론, 이렇게 한 외란 입력이 없는 경우는 상기 외란 입력 플래그 G_IN은 "0"으로 리세트된 채로 하고, 모두 이그니션 스위치가 온일 때에는, 이 샘플링 기능 및 홀드 기능을 작용하지 않는다.Here, the arithmetic processing unit 56c of the microcomputer 56 uses the above-described arithmetic processing (not shown) to apply the vertical acceleration X _FL "to each spring.

From X _RR ", for example, the vertical velocity of the vehicle body at the wheel portion as the time integral value (also described as the vertical velocity on the spring) X _FL '

X _RR 'is calculated, and the vertical velocity X _i ' (i = FL on these springs)

The target rotation angle of the step motor corresponding to RR), that is, the target position P _D of the valve body is calculated and set, and the difference value between the target position line P _D and the current position P _A is calculated. It outputs to the drive circuit 59FL-59RR, and open-loop control the damping force of each damping force variable shock absorber 3FL-3RR according to the rotation angle of the said step motor, ie, the position of a valve body. On the other hand, in response to the open loop control of the damping force of the damping force variable shock absorber 3FL-3RR, the initializing process described later is also dealt with in order to correct the deviation of the rotation angle of the step motor and the position of the valve body. With this, when the acceleration switch 53 is closed during the ignition off and power is temporarily supplied from the battery + B, the disturbance input flag G _{IN is set} to " 1 " Is set in the storage device 56d. Of course, when there is no such disturbance input, the disturbance input flag G _IN remains reset to " 0 ". When all of the ignition switches are on, this sampling function and the hold function are not operated.

In addition, the storage device 56d stores in advance a program, a control map, and the like necessary for the calculation processing of the arithmetic processing unit 56, and sequentially stores the necessary values and calculation results in the arithmetic processing.

Next, a description will be given of the calculation processing of the damping force control which is mainly performed by the arithmetic processing unit 56c of the microcomputer 56 in order to suppress a change in the vehicle body attitude occurring in the vehicle body. As the arithmetic processing for the damping force control, for example, the equivalent or almost equivalent to the arithmetic processing in FIG. 13 described in Japanese Patent Application Laid-Open No. 7-329532 is executed. Therefore, a detailed description of the logic is omitted, and only the operation is briefly described. Explain.

As described above, the damping force variable shock absorber 3FL-3RR of the present embodiment having the damping force characteristic of FIG. 3 (strictly the damping coefficient characteristic) is, for example, a relative up-down speed between the spring down-spring up on the horizontal axis. For the damping force characteristic of the sky hook principle of holding the spring up and down speed on the vertical axis, see Fig. 3 from the back, and rotate it clockwise in the clockwise direction. The sky hook principle can be more consistent with the desired damping force characteristics. And, more preferably again, by setting the damping coefficient c to linear with respect to the up-down speed X _i 'of the spring, the damping force D / F expressed by the product of both, the up-down acceleration X _i "of the spring and mass M It is also possible to effectively suppress the excitation force expressed by the product of.

Therefore, a calculation coefficient for calculating the linear damping coefficient c for the spring-like vertical velocity X _i ', which is a control input, is calculated as each target position proportional coefficient α ₁ , α ₂ in step S26 of the calculation processing, If the damping force D / F with respect to the up-and-down speed X _i ′ of the damping force characteristic curve of FIG. 3 is considered to be in a linear relationship with the position P of the stepper motor, the target position proportional coefficients α ₁ and α ₂ are By multiplying each of the pressure-side maximum position (-P _MAX ) or the stretching-side maximum position P _MAX , respectively, the valve body can obtain the target position P _D of the step motor at the step S29 or S33 of the same operation, and finally the desired damping coefficient. The rotation position of is calculated. Then, the step amount S to correct the deviation between the target position P _D and the current position P _A that must be grasped or recognized by the control unit side in the open control is output. Can be obtained by the shock absorber 3FL-3RR.

As a result, for example, during low-speed driving, the damping force D / F of each damping force variable shock absorber (3FL-3RR) is small with respect to the small excitation force (= spring up and down speed X _i ') generated during the passage of a transient protrusion. With respect to the input from the road surface, the spring shape, that is, the vehicle body moves loosely, and the riding comfort is secured. On the other hand, during high-speed driving, even in the passage of the transient projections equivalent to the above, the excitation force (= spring up and down speed X _i ') input from the road surface becomes large, so that each damping force variable shock absorber with respect to the spring up and down speed X _i (3FL) A damping force D / F of -3RR) is set large, and thus a large damping effect is applied to the spring-like body, i.e., the vehicle body, and there is no feeling of crushing. A solid feeling of following a wheel) is obtained. In addition, even at other vehicle speeds, on a minute uneven road surface such as a gravel road and a Persian road, since there is little excitation force (= spring up and down speed X _i ') acting on the vehicle body, the angular damping force variable shock with respect to the spring up and down speed X _i '. The damping force D / F of the absorber 3FL-3RR is set less, and the ride on the spring, that is, the vehicle body does not move up and down with the excitation force from the road surface, is ensured.

Here, the basic principle of the initialization process performed in the said control unit 4 is demonstrated next.

The damping force control of this embodiment also satisfies the purpose of simplifying the structure, improving control response, and the like, and as described above, the so-called open loop control of the rotation angle of the step motor, that is, the control amount of the step amount, as the control amount. In such open loop control, as already known, the presence and the magnitude of the step out are not normally recognized by the control routine, so that the step out of the input / output system is corrected by initializing the basic control origin by so-called initializing.

Here, the aspect of a basic initialization process is demonstrated briefly. First, as shown in FIG. 4, when the relationship between the stretched maximum position P _MAX at the position A and the pressurized side maximum position (-P _MAX ) at the position C is the damping force control range, the damping force control calculation is performed. It can be seen that the current position P _A used in the process is a value obtained by multiplying the control amount output in the previous calculation process, that is, the step amount S. Therefore, in the present embodiment, initialization is performed with the intermediate position B of the soft range SS as the position value "0", and the position value "0" as the control origin. Specifically, as shown in FIG. 4, the step motors 41FL-41RR are rotated stepwise in the counterclockwise direction at the initializing start point, and one end surface 44a of the projecting contact body 44 is rotated. One protruding abutment protrusion 45a of the stopper plate 45 is brought into contact with the other end surface 44b of the protruding abutment body 44 at the same time as the other protruding abutment of the stopper plate 45a. The step motors 41FL-41RR may be rotated clockwise by a predetermined number of steps S _a corresponding to the rotation angle a shown in the same drawing. Of course, the step motor 41FL-41RR is rotated stepwise in the clockwise direction from the initializing start point, and the other end surface 44b of the protruding contact body 44 is the other side of the stopper plate 45. Abutting against the protrusion 45b (in the same drawing, one end face 44a of the protrusion abutting body 44 also abuts against one protrusion butting protrusion 45a of the stopper plate 45), Thereafter, the step motor 41FL-41RR may be rotated in the counterclockwise direction by the predetermined number of steps S _b corresponding to the rotation angle b shown in the same drawing.

In order to execute this initialization process, a calculation process executed in the arithmetic processing unit 56c of the control unit 4 is shown in FIG. The arithmetic processing in FIG. 7 is executed by timer distribution processing every predetermined time DELTA T (for example, 3.3 msec). In addition, necessary data and information such as the current position P _A which is updated and stored in the storage device 56d for each arithmetic processing are frequently used in a buffer or the like of the arithmetic processing unit 56c for each arithmetic processing, even without a special input / output processing step. It shall be read.

The calculation processing, first, in step S21 the storage device (56d) of the disturbance input flag (G _IN is to determine parts of the set state of "1", the disturbance input flag G if _IN is the set state of "1" The flow advances to step S22, otherwise, the flow proceeds to step S23.

In step S22, it is determined whether or not the initialization flag INT is in a set state of "1". If the initialization INT is in a set state of "1", the flow advances to step S24. To return.

In addition, in said step S23, after initializing INT is set to "1", it transfers to the said step S24.

In step S24, the initializing process is executed as described above with reference to a table (not shown) or the like, and the flow advances to step S25 next. In other words, the initializing process is continuously executed independently without being impeded by other processing such as interrupting the timer.

In step S25, the initializing execution flag SET is set to " 1 ", and then the procedure goes to step S26.

In step S26, the disturbance input flag G _IN is reset to "0", and then the program returns to the main program.

Here, the meaning displayed by the initialization flag INT and the initialization execution flag SET and the exchange of the set state will be described later in detail, and the initialization process executed in step S24 of the arithmetic processing in FIG. Explain the operation.

For example, the final position of the valve element (that is, the position immediately before the initialization is executed) is assumed to be in the position as shown in FIG. 8, and the disturbance input flag at the sampling time at which the calculation process of FIG. When G _IN or the initializing flag INT is set to "1", the step amount S gradually decreases by rotating the step motor 41FL-41RR counterclockwise in step S4 of the calculation processing of FIG. Is outputted as a control signal every predetermined time, which is the valve body 31 and the contacting protrusion 44 at the same time. However, the step motor 41FL-41RR rotates its counterclockwise stepwise. Rotation while gradually reducing the pressure, the rotational contact to the pressure side maximum position (P _MAX ), so that the projecting contact body 44 of the stopper mechanism 46 is each projecting contact projections (45a, 45b) of the stopper loop 45 Against the teeth It is not rotated. In this state, by outputting the predetermined step amount S _a to the step motor 41FL-41RR, the step motor 41FL-41RR is rotated clockwise by the rotation angle a so that the projecting contact body 44, that is, the valve The position P of the sieve 31 is positioned at the position value "0", and the initialization completion flag SET is set to "1". In other words, in the present embodiment, when the step motor 41FL-41RR is rotated counterclockwise by a predetermined rotational angle, the stepped motor is held for a predetermined time for each rotational position and the predetermined time of which the supply voltage is turned OFF. The driving force is "0". As a result, the driving force of the step motor 41FL-41RR is interrupted during this initializing. In addition, as shown in FIG. 8, for example, the angle from the final position P to the stretching side maximum position P _MAX is set to γ, and the pressure side maximum from the assumed maximum passing position P _N reached by the initializing process. If the angle to position (-P _MAX ) is δ, the angle δ is set to be larger than the angle γ so that the final position P must reach the maximum pressure-side position (-P _MAX ) even within the damping force control range. have.

Therefore, according to the arithmetic processing shown in FIG. 7, there is a disturbance input to the vehicle body such as the lifting and lowering of the occupant and the falling of the load or the deliberately rocking of the vehicle during the ignition off, which is the current position P of the step motor 41FL-41RR. _{In the} case of a large acceleration input that causes a step out of the position P stored in the microcomputer 56 constituting the control unit 4 with _A , power is supplied to the microcomputer 56 temporarily by the acceleration switch 53. Is supplied, whereby the disturbance input flag G _IN is set to " 1 " in the microcomputer 56, for example, simultaneously with or immediately after the ignition switch in which the arithmetic processing in Fig. 7 is started. From the same switch S21 to the switch 23, the initializing flag INT is set to "1", and the above-mentioned initializing is forcibly executed. The out-of-gassing which may have occurred in the stepper motor 41FL-41RR by the disturbance input is corrected as soon as possible.

By the way, in reality, during the low speed driving such as when the vehicle starts or stops at the same time as the ignition on, the noise caused by the rotation and stop of the step motor 41FL-41RR by the initializing process, or the projecting hit Noise or the like that the contact body 44 contacts each of the protruding butting protrusions 45a and 45b of the stopper plate 45 may be transmitted to the vehicle interior as abnormal noise. Therefore, in the present embodiment, when there is no disturbance input, that is, acceleration input, which causes the step motor 41FL-41RR to step out during the ignition off, and as a result, the disturbance input flag G _IN is not set to "1". In the same manner as in Japanese Patent Application Laid-Open No. Hei 7-329532, the step motor is initialized at a time when the vehicle speed is increased to some extent and the load noise transmitted to the vehicle interior is increased to some extent. Specifically, the according to the initializing of the step motor (41FL-41RR) than the level of noise transmitted to the cabin, the predetermined vehicle speed increases the noise level, such as road noise transmitted to the cabin and to the required speed value V ₀ When the vehicle speed detection value V detected by the vehicle speed sensor 52 is equal to or more than the predetermined value V ₀ , execution of the initialization of each step motor 41FL-41RR is permitted. Specifically, the initializing flag INT may be set and cleared by individual arithmetic processing, and the initializing flag INT may be set to "1" when the vehicle speed detector V is equal to or larger than a predetermined value V _0. . As a result, in such a traveling state at the vehicle speed, it is conceivable that the noise transmitted in the vehicle with the initialization of the step motors 41FL-41RR is masked by the load noise transmitted in the vehicle. When the initializing is completed after the various problems described later are cleared, the initializing completion flag END is set to "1".

On the other hand, when the vehicle speed is increased to a certain degree or more, the initializing is executed or the disturbance input flag G _IN is set to "1". As a result, the initializing is executed simultaneously with or immediately after the ignition is turned on. In addition, when the vehicle oscillates while the initialization is not completed, the damping force is variable when the input to the shock absorber from the road surface acting during the initialization and the input to the shock absorber due to the body fluctuation are large. It is considered that the piston speed of the shock absorber is increased, and as a result, there is a possibility that the step motor may be out of step due to the fluid force passing through the orifice as described above.

Thus, in the present embodiment, in order to perform the correct position " 0 " of the stepper motor, it is determined whether or not it is possible to perform the initialization of the stepper motor or whether the initialization that has been executed is completed and the microcomputer ( FIG. 9 shows arithmetic processing executed by arithmetic processing unit 56c. This calculation process is basically the same as that described in FIG. 17 of Japanese Patent Laid-Open No. 7-329532, but since there are differences in detail, the entire logic will be described briefly. That is, each flag and counter used in this arithmetic processing are the same as those described in the above publications, and the details are referred to the above publications. It is also assumed that, among these flags and timer counters, at least the initialization flag INT and the initialization execution flag SET are communicated with the arithmetic processing in FIG. 15 via the storage device 56d.

That is, the process of FIG. 9 is executed as a timer distributing process every predetermined time [Delta] T (e.g., 3.3 mm) (however, the subroutine that executes the initializing process is independent logic that is not interrupted). determining whether or not the disturbance input flag G _iN is reset for "0" at step S20, and the disturbance input flag G _iN this case, the reset state of "0", and proceeds to step S1, otherwise The flow proceeds to step S6.

In step S1, the vehicle speed V detected by the spring up / down acceleration X _2i " (i = FL-RR) and the vehicle speed sensor 52 is read. In step S2, the vehicle speed V is _{equal to} or greater than the predetermined vehicle speed value V _0. If the process proceeds to step S3, otherwise, the process proceeds to step S19. In step S3, if the initialization completion flag END is in the reset state of "0", the process proceeds to step S5. In step S5, if the initialization INT is set to " 1 ", the process proceeds to the step S6, and otherwise, the process proceeds to step S7.

Here, in step S7, when the absolute value | _X2i "of the spring-like up-down acceleration detection value is smaller than the predetermined predetermined up-down acceleration value X _2i " which causes a step-out to the said step motor, it transfers to step S8, If not, the flow proceeds to step S4. In step S8, the timer counter CNT is incremented by " 1 ", and then the flow advances to step S9. When the timer counter CNT is equal to or greater than the predetermined counter value CNT ₀ , the flow advances to step S10. Returns to the main program.

In step S10, the initializing flag INT is set to " 1 ", then the routine advances to step S11. After the initializing execution flag SET is reset to " 0 ", the process proceeds to step S12 and the timer counter is cleared. Then return to the main program.

On the other hand, in the step S6, the spring absolute value of the vertical acceleration detection | X _2i | if it is "r a previously set predetermined upper and lower acceleration value X2io" proceeds to step S13 if not less than, is not, the process moves to step S14. In step S13, the initializing completion flag NEND is set to " 1 ", and then the flow advances to step S14. When the initializing execution flag SET is set to " 1 " The flow advances to step S15, otherwise the flow returns to the main program.

This step S15 resets the initialization flag INT to "0", and then proceeds to step S16, and goes to step S17 when the initialization completion flag NEND is in the reset state of "0". If not, the flow proceeds to Step S18. In step S17, the initializing completion flag END is reset to " 1 ", and then the process proceeds to step S18, and the initializing completion flag NEND is reset to " 0 ". To return.

On the other hand, in step S19, when the initialization flag INT is in the reset state of "0", the process proceeds to the step S4, otherwise, the process proceeds to the step S6. In step S4, the timer counter CNT is cleared and the program returns to the main program.

The calculation processing operation of FIG. 9 will be briefly described in view of the correlation with the calculation processing of FIG.

First, when there is no disturbance input during the ignition off, and as a result, the ignition switch is turned on while the disturbance input flag GIN is reset to "0", the vehicle speed V detected by the vehicle speed sensor 52 becomes As long as the predetermined vehicle speed value V0 is not _equal to or greater than the predetermined vehicle speed value V ₀ , the process proceeds from the step S2 to the step S4 via the step S19, and as a result, the timer counter CNT is cleared, and thus the program returns to the main program. The initializing flag INT is kept at " 0 " and the initializing process according to Fig. 7 is not executed.

On the other hand, when the vehicle speed V becomes _equal to or greater than the predetermined vehicle speed value V ₀ , the process proceeds to step S3, and since the initialization completion flag END is kept at "0", the process proceeds to step S5, and then the initials. Since the rise flag INT is still held at "0", the routine advances to step S7. Here, if the vertical acceleration X _2i on the spring acting on the vehicle body is smaller than the predetermined vertical acceleration value X _2i0 causing the stepping in the step motor, the process proceeds to step S8 and the timer count CNT is incremental. The timer count CNT is _equal to or greater than the predetermined count value CNT ₀ . That is, the state where the vehicle speed V is _equal to or greater than the predetermined vehicle speed value V ₀ and the vertical acceleration X _2i "on the spring" is smaller than the predetermined vertical acceleration value X _2i0 "for a predetermined time (= CNT ₀ · Δ T) Subsequently, the process proceeds from step S9 to step S10, and the initialization flag INT becomes "1". In addition, the initializing execution flag SET is reset to "0" in step S11, and then the process goes to step S12. The timer count CNT is reset. As a result, the vehicle continues to run on a good road which is relatively stable at a vehicle speed higher than the predetermined vehicle speed value V ₀ , and the initializing process by the arithmetic processing step S24 of FIG. 7 is performed. The noise transmitted to the inside of the vehicle according to the initialization caused by the load noise transmitted to the inside of the vehicle even when the vehicle speed V is initialized while the vehicle speed V is running above the predetermined vehicle speed value V ₀ . Is masked so the crew doesn't feel noise. In addition, since the vehicle is stably running on a good road where the vehicle is relatively flat for the predetermined time T or more, it is unlikely that the step out occurs due to a fluid force caused by a large road surface input or a vehicle body oscillation input during the initializing performed subsequently.

On the other hand, when the disturbance input flag G _IN is at " 1 ", i.e., it is input to the disturbance during ignition off, and as a result, initialization is executed by the calculation processing of FIG. 7 simultaneously with or immediately after ignition on. And the vehicle speed V is smaller than the predetermined vehicle speed value V ₀ , the initializing completion flag END is set to "0" once the initialization flag INT is set to "1". If there is any, the process proceeds to Step S6. Here, when the initializing process is finished by the arithmetic processing of FIG. 7, the initializing flag INT and the disturbance input flag G _IN are set to "0". In this state, in any case, the initializing process is being executed. If the vertical acceleration X _2i on the spring acting on the vehicle body becomes equal to or greater than the predetermined vertical acceleration value X _{2i 0} causing the stepping by the step motor during the _initializing , the process proceeds to step S13. The initializing completion flag NEND is set to "1". Therefore, when the initializing process by the arithmetic processing of FIG. 7 is complete | finished, and the said initializing execution flag SET is set to "1", it transfers to the process of initializing flag (step S14 of FIG. 9 from step S14). INT) is set to "0", and the initialization completion flag NEND is reset to "0". In other words, only when the vertical acceleration X _2i on the spring causing the stepping in the step motor occurs during the initialization, the process proceeds to step S17 and the initialization completion flag NED is set to "1". Since the initializing process is surely finished without any problem, the flow of returning from the step S3 to the main program as it is after all is repeated, and the initializing is not executed again.

On the other hand, when the initializing is executed, the vertical acceleration X _2i on the spring that causes the stepping motor in the stepper motor is generated, whereby the initializing completion flag NEND is set to " 1 " Since the initialization completion plug END remains reset to " 0 " even after the initialization is executed, it is again satisfied when the initialization flag * INT is set again to " 1 " When the initialization flag INT is set to " 1 " by the arithmetic processing of 7 degrees, the initializing process is performed again by the arithmetic processing of FIG. the vertical acceleration (X _2i) "is generated, and wherein the initializing completion flag (NEND) is a result" when set to the 1 ", to meet the above conditions, the initializing completion plug That the initializing is repeated executed until (END) is set to, since the "1", that is, a certain initializing, completed.

Therefore, in the present invention, initialisation is performed at the same time as or immediately after the ignition on the disturbance occurring during the ignition off, and the vehicle is started while the vehicle is not completed, or the vehicle crew is lifted or the cargo is dropped intentionally or intentionally. If the vertical acceleration (X _2i ) on the spring causing the stepping by the oscillation at that time occurs, the initializing is repeated while waiting for the time when the predetermined condition is satisfied. Means are taken, and as a result, appropriate damping force control can be ensured.

51PR)가 본 발명의 서스펜션 제어 장치의 스프링상이 상하 속도 검출 수단에 상당하고, 이하와 동일하게 상기 콘트롤유니트가 제어 수단에 상당하며 상기 속도 센서(52) 및 콘트롤유니트(4)로 실행되는 제9도의 연산처리의 스텝 S1이 차속 검출 수단에 상당하고, 상기 콘트롤유니트(4)로 실행되는 제7도 및 제9도의 연산처리가 제어원점 교정 수단에 상당하며, 상기 가속도 센서(53) 및 콘트롤유니트(4) 및 제7도의 연산처리 스텝 S21이 외란 입력 검출 수단에 상당하고, 상기 콘트롤유니트(4)로 실행되는 제7도의 연산 처리 스텝 S21 및 스텝 S24가 외란 입력시 제어 원점 교정 수단에 상당하다.The vertical acceleration sensor (51FL) mentioned above by the above

51PR) is a ninth step in which the spring on the suspension control device of the present invention corresponds to the up and down speed detecting means, and the control unit corresponds to the control means and is executed by the speed sensor 52 and the control unit 4 as follows. Step S1 of the arithmetic processing in Fig. 1 corresponds to the vehicle speed detecting means, and the arithmetic processing in Figs. 7 and 9 executed by the control unit 4 corresponds to the control origin calibration means, and the acceleration sensor 53 and the control unit (4) and the calculation processing step S21 of FIG. 7 correspond to a disturbance input detection means, and the calculation processing steps S21 and step S24 of FIG. 7 performed by the said control unit 4 correspond to the control origin correction means at the time of a disturbance input. .

In addition, in the above embodiment, the case where the attitude change of the vehicle body due to the vibration input from the road surface is suppressed is described. However, this is not the only case. Control may be performed in parallel.

In the above embodiment, the case where the microcomputer 56 is applied and controlled has been described. However, the present invention is not limited thereto, and electronic circuits such as arithmetic circuits may be combined.

1RR) 위치에서 상하 가속도 센서(51FL

51RR)를 설치한 경우에 대해서 설명했지만, 어느 것도 하나의 상하 가속도 센서를 생략하여 생략한 위치의 상하 가속도를 다른 상하 가속도 센서의 값으로부터 추정하도록 하여도 좋다.Further, in the above embodiment, each wheel of the vehicle body 2 (1FL)

Vertical acceleration sensor (51FL) in position 1RR

51RR) has been described, either of which may omit one vertical acceleration sensor so that the vertical acceleration of the omitted position may be estimated from the values of the other vertical acceleration sensors.

As described above, according to the suspension control device according to claim 1 of the present invention, when there is a disturbance input that results in a predetermined or more acceleration input, such as lifting or lowering of a crew, deliberately swinging the vehicle body during ignition off, etc. The damping force variable shock absorber is eliminated as soon as possible by eliminating the stepping of the remaining stepper motor until the vehicle speed reaches a predetermined value by performing the control home calibration (initialization) of the stepper motor at the same time as or immediately after the switch-on. It is possible to start appropriate damping force control early.

In addition, according to the suspension control device according to claim 2 of the present invention, an acceleration switch is installed between a supply power supply (battery) of a vehicle and a control unit constituting a control means, and an acceleration path that causes a step out of the step motor is caused. When the disturbance is input, the acceleration switch is closed so that power is supplied to the control unit, so that the input of the disturbance can be reliably and easily detected even during ignition on.

Claims (2)

A damping force variable shock absorber that is installed between the vehicle body side member and the wheel side member, and controls the valve body by a step motor driven according to an input control signal to change the axle through which the fluid passes. And a spring-like vertical speed detecting means for detecting a spring-like vertical speed of the vehicle body and a damping force for suppressing a change in attitude of the vehicle body based on at least the spring-like vertical speed detected value detected by the spring-like vertical speed detecting means. A control means for setting a target rotational position of the valve element, and outputting the control signal to the stepper motor to open-loop the control so as to move the valve element to the target rotational position, wherein the control means includes a front-rear direction of the vehicle. Vehicle speed detecting means for detecting the speed and at least the vehicle speed detecting value detected by the vehicle speed detecting means are set in advance. A suspension control apparatus comprising a control origin calibration means for performing control origin calibration of the step motor when the predetermined value is equal to or greater than a predetermined value, wherein the control origin calibration means detects that a predetermined or more disturbance is input to the vehicle body while the ignition switch is turned off. Disturbance input detection means and control origin correction means at the time of disturbance input when the disturbance is input to the vehicle body while the ignition switch is turned off by the disturbance input detection means, the control origin calibration of the switch motor is performed immediately after the ignition switch is turned on. Suspension controller, characterized in that provided with. The suspension control device according to claim 1, wherein the disturbance input detecting means comprises an acceleration switch that is closed when a predetermined or more acceleration is input to the vehicle body.

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