JP2007302075A - Vehicular stabilizer system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acknowledge the specified state of a vehicle by using a stabilizer force, and to cope with the specified state, in an active stabilizer system capable of changing the stabilizer force by the operation of an actuator. <P>SOLUTION: A set actuator force is succesively exhibited in both directions at each setting time. In that case, a normal rotation angle θ<SB>CW</SB>and a reverse rotation angle θ<SB>CCW</SB>of a motor in the actuator are obtained, and a difference θ<SB>D</SB>between them is obtained. When the difference θ<SB>D</SB>is larger than a threshold θ<SB>D</SB>o, it is acknowledged that a vehicle is in a state standing by one-side wheels, and a state that does not exhibits the stabilizer force is obtained. On the other hand, by the difference θ<SB>D</SB>, a difference state of spring rates of right and left air springs can be acknowledged. On the basis of acknowledgment, the right and left spring rates can be made equal by communicating chambers of the air springs. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stabilizer system mounted on a vehicle, and more particularly, to a stabilizer system that includes an actuator and can change a stabilizer force exerted by a stabilizer bar by operating the actuator.

The stabilizer system is a system that suppresses the roll of the vehicle body by a stabilizer force that is a force exerted by the stabilizer bar (for example, a force generated by twisting the stabilizer bar). In recent years, for example, described in the following patent documents A so-called active stabilizer system, that is, a system in which the stabilizer force can be changed according to the turning state of the vehicle by the operation of an actuator has been studied, and has already been put into practical use in some vehicles.
Special table 2002-518245 gazette

  The active stabilizer system is still under development, and leaves plenty of room for improvement to improve practicality. This invention is made | formed in view of such a situation, and makes it a subject to provide a highly practical vehicle stabilizer system.

  In order to solve the above-described problems, a vehicle stabilizer system according to the present invention is a system that can change a stabilizer force by an operation of an actuator, and a control device that controls the actuator has a set actuator for a set time. Actuator operation is controlled so that force is sequentially exerted in both directions, and the function of acquiring the relative displacement index amount that indicates the relative displacement amount at both ends of the stabilizer bar at that time in accordance with the direction of the actuator force is obtained. It was configured as described above.

  According to the vehicle stabilizer system of the present invention, it is possible to obtain a difference in the direction of the stabilizer force with respect to the change characteristic of the vehicle body posture due to the stabilizer force, and to recognize the state of the vehicle by the presence / absence and degree of the difference. It is possible to maintain or change the state of the vehicle based on the certified state, adapt the control form of the system, and the like. By having such a function, the system of the present invention becomes a practical system.

Aspects of the Invention

  In the following, some aspects of the invention that can be claimed in the present application (hereinafter sometimes referred to as “claimable invention”) will be exemplified and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is merely for the purpose of facilitating the understanding of the claimable inventions, and is not intended to limit the combinations of the constituent elements constituting those inventions to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which some constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

  In the following embodiments, the item (1) corresponds to claim 1, the items (2) to (5) correspond to claims 2 to 5, respectively, and the items (7) and (8). The terms correspond to claims 6 and 7, respectively.

(1) A stabilizer bar that has both ends connected to each of the wheel holding members that hold each of the left and right wheels, and suppresses the roll of the vehicle body by a stabilizer force that is a force exerted by itself;
An actuator for controlling the stabilizer force by controlling the operation of the stabilizer bar in addition to causing the stabilizer bar to exhibit a stabilizer force corresponding to an actuator force which is a force exerted by itself;
A vehicle stabilizer system comprising: a control device that controls the operation of the actuator;
The control device is
Control of the operation of the actuator so that the set actuator force is sequentially exhibited in both directions for a set time, and a relative displacement index amount indicating the relative displacement amount at both ends of the stabilizer bar at that time The stabilizer system for vehicles which has a relative displacement amount difference acquisition part which acquires the difference by the direction of an actuator force.

  The aspect of this section is an aspect relating to a so-called active stabilizer system. In an active stabilizer system provided with an actuator, the direction and magnitude of the stabilizer force exerted by the stabilizer bar is the direction and magnitude corresponding to the actuator force exerted by the actuator. Therefore, if a certain amount of actuator force is exerted for a certain period of time as in this aspect, a certain amount of stabilizer force is applied as a relative force to the left and right wheel holding members (for example, suspension arms). If the actuator force is exerted in the opposite direction, the same relative force is applied to the left and right wheel holding members in the opposite direction. This relative force acts as a force in a direction in which the wheel and the vehicle body are approached / separated, and both ends of the stabilizer bar are relatively displaced by an amount corresponding to the force. Usually, when a stabilizer force of the same magnitude is alternately applied in both directions, the relative displacement amounts at both ends of the stabilizer bar should be the same regardless of the direction of the stabilizer force. However, since the relative displacement amount of both ends of the stabilizer bar depends on the elastic force of the suspension spring, for example, when the spring rates of the left and right suspension springs are different, one of the wheel holding members is the bound stopper. Alternatively, when the right and left balance is lost in the configuration of the suspension device and the situation where the suspension device is placed, such as when it is in contact with the rebound stopper, the relative displacement amount of both ends of the stabilizer bar is A phenomenon may occur depending on the direction of the stabilizer force. That is, a difference in the direction of the stabilizer force occurs with respect to the change characteristic of the vehicle body posture due to the stabilizer force. As described above, the stabilizer system according to the aspect of this section has a function of controlling the actuator to acquire the difference in the relative displacement amount. It is possible to certify the state of the vehicle with respect to the degree, etc., and based on the qualification, maintain or change the state of the vehicle, or change the control system of the stabilizer system to the state of the authorized vehicle. It can be adapted.

  In the stabilizer system of this aspect, the stabilizer device is configured by the stabilizer bar and the actuator, but the configuration of the stabilizer device is not particularly limited. For example, as will be described later, the stabilizer bar is divided into two at the center and is constituted by a pair of stabilizer bar members, and an actuator is disposed between the pair of stabilizer bar members. However, the actuator force may be generated so as to relatively rotate the pair of stabilizer bar members. Also, an actuator is disposed between one end of the stabilizer bar and the wheel holding member so that the actuator generates an actuator force that changes the distance between the one end and the wheel holding member. It may be a simple configuration. Incidentally, the actuator may operate based on any force. For example, it may be a fluid actuator that operates by hydraulic pressure or the like, or may be an electromagnetic actuator that includes an electric motor or the like as a drive source.

  In the aspect of this section, the “control device” can be configured mainly by a computer, for example. The main function of the control device is based on the turning state of the vehicle (for example, the running speed of the vehicle, the steering angle, the roll moment received by the vehicle body, the lateral acceleration generated in the vehicle body, the yaw rate of the vehicle, etc.). The actuator can be configured so as to have a function of controlling the actuator so as to obtain an appropriate stabilizer force that provides an appropriate roll restraining force. The control in this case may be control with the actuator force as a direct control target, or may be control with the operation amount of the actuator as a direct control target. In the former, for example, based on the turning state of the vehicle, the target stabilizer force is determined as a share of the stabilizer bar of the force against the roll moment received by the vehicle body in the turning state, and the target for generating the target stabilizer force is determined. What is necessary is just to determine an actuator force and control an actuator so that the target actuator force may be exhibited. In the latter case, for example, when the stabilizer bar has rigidity (apparent rigidity) such that the roll amount of the vehicle body becomes an appropriate roll amount when the target stabilizer force is exerted, And the actuator may be controlled so that the operation amount becomes the target operation amount.

  The “relative displacement index amount” referred to in this section is a concept including a wide range of parameters that directly or indirectly represent the relative displacement amounts at both ends of the stabilizer bar, and is acquired by the “relative displacement amount difference acquisition unit”. As the “difference in relative displacement index amount”, for example, when a vehicle is provided with a stroke sensor for detecting a separation distance between a wheel and a vehicle body (hereinafter, referred to as “wheel vehicle body distance”). It is possible to adopt the wheel-to-vehicle distance based on the detection value of the stroke sensor, and it is possible to adopt the difference in the operation amount of the actuator as will be described later.

  It should be noted that the control of the operation of the actuator executed by the “relative displacement amount difference acquisition unit” (hereinafter also referred to as “bidirectional force exerting control”) is bidirectionally sequentially performed for a predetermined time and a predetermined magnitude. In this bidirectional force exerting control, the actuator force in any direction may be exerted first. In order to prevent the occupant from sensing changes in the vehicle body posture due to the stabilizer force, it is desirable that the actuator force in this control be as small as possible within a range in which the difference in relative displacement index amount can be detected.

  In addition, the above-described processing executed by the relative displacement amount difference acquisition unit (which includes both-force control and is hereinafter referred to as “relative displacement amount difference acquisition processing”) is intermittent at a set time. The process may be executed when the predetermined start condition is satisfied. Note that the relative displacement amount difference acquisition process does not substantially exhibit the stabilizer force in view of the fact that the actuator force of the same magnitude is exhibited in both directions to acquire the relative displacement index amount difference. It is desirable to execute in a state, and it is desirable to execute in a state where it can be considered that the vehicle is not traveling or not traveling in consideration of fluctuations in the relative displacement index amount due to external input from the road surface.

  (2) The vehicle stabilizer system according to (1), wherein the relative displacement amount difference acquisition unit acquires the difference in the operation amount of the actuator according to the direction of the actuator force as the difference in the relative displacement index amount. .

  In a general active stabilizer system, the above-described relative displacement amount depends on the operation amount of the actuator. In the aspect of this section, the difference in the operation amount of the actuator depending on the direction of the actuator force is acquired as the difference in the relative displacement index amount by utilizing the fact. According to the aspect of this section, even in a vehicle that is not equipped with the above-described stroke sensor, it is possible to recognize the state of the vehicle with respect to the presence or absence, degree, etc. of the left-right balance by the relative displacement amount difference acquisition process. It becomes.

  (3) Specification that the control device recognizes that the state of the vehicle on which the stabilizer system is mounted is in a specific state based on the difference between the relative displacement index amounts acquired by the relative displacement amount difference acquisition unit The vehicle stabilizer system according to the item (1) or the item (2), which includes a state recognition unit.

  The mode of this section is a mode in which a limitation is added to the usage mode of the difference between the relative displacement index amounts acquired by the relative displacement amount difference acquisition process. The “vehicle state” in this section means, for example, the state of the vehicle related to the presence / absence, degree, etc. of the above-described left / right balance loss, and the processing (hereinafter referred to as “specific state”) by the “specific state recognition unit”. The “specific state” that is recognized in the “accreditation process” is a state in which the left and right balance is broken, specifically, a vehicle as described later is standing on one wheel. Or a state in which the spring rate of the suspension spring is different between the left and right.

(4) The specific state authorization unit
When the difference between the relative displacement index amounts is larger than a set threshold value, the one-wheel standing recognition unit that recognizes that the state of the vehicle is in a one-wheel standing state in which the difference in grounding load between the left and right wheels is large. The vehicle stabilizer system according to item (3).

  The aspect of this paragraph is an aspect which limited the specific state recognized by the said specific state recognition process. In the single wheel standing state, for example, since one wheel holding member is in contact with the bound stopper or the rebound stopper, the relative displacement amount of both ends of the stabilizer bar by the bidirectional force control is the stabilizer force. The phenomenon of different depending on the direction can occur. Specifically, for example, when trying to further bounce the side that is in contact with the bound stopper in the bound direction, the bound operation is prohibited by the bound stopper. This is because the relative displacement amounts are different. That is, according to the aspect of this section, it is possible to easily recognize that the road surface on which the vehicle is traveling is a bad road such as a mogul road.

  (5) An actuator neutralization state realizing unit that realizes a state where the actuator cannot exert an actuator force when the control device is recognized by the single wheel standing recognition unit that the vehicle is in a single wheel standing state. The vehicle stabilizer system according to (4).

  In the “state in which the actuator force cannot be exhibited” referred to in the aspect of this section, the stabilizer bar is in a state in which the stabilizer force cannot be exhibited. On bad roads such as a mogul road, the stabilizer force contributes to the deterioration of the wheel ground contact. Therefore, according to the aspect of this section, when it is recognized that the vehicle is standing on one wheel, a state where the stabilizer force cannot be exhibited is realized. Will be improved.

(6) The actuator has an electric motor as a power source,
The state where the actuator cannot exert the actuator force is realized by cutting off the electrical continuity between all the input terminals of the electric motor and the power source and the mutual electrical continuity between the input terminals (5). The vehicle stabilizer system according to Item.

  The mode of this section is a mode in which the state where the actuator force cannot be exerted is limited to a specific state, and is suitable for a system in which the actuator exhibits the actuator force by the power of the electric motor, that is, an electric active stabilizer system. It is an aspect. The state described in this section corresponds to a state where each phase of the electric motor is opened so that an electromotive force cannot be generated even when the electric motor is operated by an external input.

(7) The vehicle equipped with the stabilizer system is a vehicle including an air spring as a suspension spring,
When the specific state recognition unit determines that the difference between the relative displacement index amounts is greater than a set threshold value, the vehicle state indicates that the spring rate of the left and right air springs is caused by the difference in the air amount in the air chamber. The vehicle stabilizer system according to any one of (3) to (6), further including a spring rate difference recognition unit that recognizes that the spring rates are different from each other.

  The air spring is a spring that exerts a spring force that depends on the air pressure in the air chamber. Generally, by adjusting the amount of air in the air chamber, the spring length of the spring is changed, so It has a function of adjusting the vehicle height by changing the distance. However, for example, when the vehicle height adjustment is performed on an inclined road surface or an uneven road surface, even if the distance between the left and right wheel bodies matches, The amount of air is not necessarily equal, and the spring rates of the left and right air springs (the elastic force of the air spring with respect to the distance between the wheels and the body, corresponding to the spring constant when they are in a linear relationship) are different. Such a phenomenon occurs. Such a difference in the spring rate contributes to an unbalance between the left and right of the behavior of the vehicle when the vehicle is steered to change lanes (lane change), for example. If the spring rates of the left and right air springs are different, even if a stabilizer force of the same magnitude is applied, the variation in the distance between the wheels and the vehicle body depends on the direction of the stabilizer force due to the difference in the spring rate. As a result, a difference in relative displacement amount between both ends of the stabilizer bar occurs. The aspect described in this section is an aspect configured to recognize the above-described spring rate difference state as a specific state by utilizing this phenomenon. According to the aspect of this section, the steering stability of the vehicle is improved. It becomes possible to easily recognize one factor that inhibits.

  (8) A spring rate equalization state realizing unit that realizes a state in which the spring rates of the left and right air springs are equal when the control device determines that the vehicle is in a spring rate difference state by the spring rate difference recognition unit. The vehicle stabilizer system according to (7).

  According to the aspect of this section, when it is determined that the spring rate is different, the difference in the spring rate is eliminated, and for example, the steering stability of the vehicle is ensured.

  (9) The vehicle stabilizer system according to (8), wherein the state in which the spring rates of the left and right air springs are equal is realized by communicating the air chambers of the left and right air springs with each other.

  The mode of this section is a mode in which a specific method for realizing a state where the spring rates of the left and right air springs are equal is limited to a specific method. According to the aspect of this section, it is possible to easily eliminate the difference in the spring rate between the left and right air springs.

(10) The stabilizer bar is
Each of them has a torsion bar portion disposed on one axis extending in the vehicle width direction, extends continuously across the torsion bar portion and intersects with the torsion bar portion, and is connected to the wheel holding member at the tip portion. Comprising a pair of stabilizer bar members having arm portions,
The vehicle stabilizer system according to any one of (1) to (9), wherein the actuator relatively rotates a torsion bar portion of the pair of stabilizer bar members around the axis.

  The aspect described in this section is an aspect in which a limitation relating to the specific structure of the stabilizer device is added. According to the aspect of this section, an active stabilizer system capable of efficiently changing the roll suppression force exhibited by the stabilizer bar is provided. It is feasible.

  (11) The actuator includes a housing, an electric motor each supported by the housing, and a speed reducer that decelerates the rotation of the electric motor, and the actuator of the pair of stabilizer bar members The vehicle stabilizer system according to (10), wherein one torsion bar portion is connected to the housing in a relatively non-rotatable manner, and the other torsion bar portion is connected to the output portion of the speed reducer in a relatively non-rotatable manner.

  The aspect described in this section is an aspect in which the actuator is electrically driven in the stabilizer device having the above structure, that is, a specific structure of the electrically active stabilizer system is limited. According to the aspect of this section, the active control of the stabilizer device can be more efficiently realized by utilizing the good controllability of the electric motor. In the actuator according to this aspect, the actuator force can be controlled by controlling the electric power supplied to the electric motor.

  Hereinafter, some embodiments of the present invention and modifications thereof will be described in detail with reference to the drawings. In addition to the following examples, the present invention is implemented in various modes including various modes modified and improved based on the knowledge of those skilled in the art, including the mode described in the above [Mode of Invention]. be able to.

<< First Example >>
(A) Configuration of Stabilizer System FIG. 1 schematically shows a vehicle stabilizer system 10 that is an embodiment of the claimable invention. The stabilizer system 10 includes two stabilizer devices 14 disposed on the front wheel side and the rear wheel side of the vehicle. Each of the stabilizer devices 14 includes a stabilizer bar 20 connected to each of suspension lower arms as wheel holding members that hold the left and right wheels 16 at both ends via a link rod 18 as a connecting member ( (See FIG. 2). The stabilizer bar 20 includes a pair of stabilizer bar members into which the stabilizer bar 20 is divided, that is, a right stabilizer bar member 22 and a left stabilizer bar member 24. The pair of stabilizer bar members 22 and 24 are connected to each other via an actuator 30 so that they can rotate relative to each other. Generally speaking, the stabilizer device 14 includes the left and right stabilizer bar members 22 and 24. By relative rotation, the apparent rigidity of the entire stabilizer bar 20 is changed to suppress the roll of the vehicle body.

  FIG. 2 schematically shows one stabilizer device 14. The vehicle equipped with the stabilizer system 10 includes four independent suspension devices 38 provided for each of the four wheels 16. The suspension device 38 is of a generally well-known double wishbone type, and has an upper arm 42 as a wheel holding member whose one end is rotatably connected to the vehicle body and the other end is connected to the wheel 16. And a lower arm 44 (see FIG. 5). The upper arm 42 and the lower arm 44 are rotated around the one end portion (vehicle body side) with the approach and separation of the wheel 16 and the vehicle body (meaning relative vertical movement), and the other end portion (wheel side). ) Is moved up and down with respect to the vehicle body. The suspension device 38 also includes a shock absorber 46 and a suspension spring 48 (in this device, “coil spring”). The shock absorbers 46 and the springs 48 are respectively connected at one end to the vehicle body side mount and at the other end to the lower arm 44. Due to such a structure, the suspension device 38 functions to elastically support the wheel 16 and the vehicle body, and to generate a damping force against vibration accompanying the approaching and separation. Further, each suspension device 38 includes a bound stopper 50 and a rebound stopper 52 that are fixed to the vehicle body, and the bound stopper 50 and the rebound stopper 52 come into contact with the lower arm 44, whereby the lower arm 44 with respect to the vehicle body. The upper and lower limits of the distance between the wheel bodies are restricted by restricting the rotation (see FIG. 6).

  As shown in FIG. 2, the pair of stabilizer bar members 22 and 24 are respectively integrated with the torsion bar portion 60 extending to substantially the same length in the vehicle width direction and the torsion bar portions 60 so as to intersect with each other. It can be divided into an arm portion 62 extending generally in the longitudinal direction of the vehicle. The torsion bar portion 60 has a linear shape, and the length between the actuator 30 and the arm portion 62 is substantially equal to each other.

  The torsion bar portion 60 of each stabilizer bar member 22, 24 is rotatably supported by a support portion 64 fixedly provided on the vehicle body at a location near the arm portion 62, and is arranged coaxially with each other. The actuator 30 described above is disposed so as to connect the left and right torsion bar portions 60, and will be described in detail later. The end portions of the torsion bar portions 60 (end portions opposite to the arm portions 62). Are respectively connected to the actuator 30. On the other hand, the end of each arm 62 (the end opposite to the torsion bar 60) is connected to the lower arm 44, which is a wheel holding member, via the link rod 18. The stabilizer device 14 is configured such that each of the restricting members 66 fixedly provided on each of the torsion bar portions 60 is in contact with the side surfaces of the two support portions 64 facing each other, so that Position fluctuation is regulated.

  The actuator 30 employs the same structure for both the front wheel side and rear wheel side stabilizer devices 14, and as schematically shown in FIG. 3, an electric motor 70 and a speed reducer that decelerates the rotation of the electric motor 70. 72. The electric motor 70 and the speed reducer 72 are provided in a housing 74 that is an outer shell member of the actuator 30. As can be seen from the figure, the left stabilizer bar member 24 is fixedly connected to the end of the housing 74, and the right stabilizer bar member 22 is disposed so as to extend into the housing 74, and The housing 74 is supported so as to be rotatable and not movable in the axial direction. An end portion of the right stabilizer bar member 22 existing in the housing 74 is connected to the speed reducer 72.

  The electric motor 70 includes a plurality of stator coils 84 fixedly arranged on one circumference along the inner surface of the peripheral wall of the housing 74, a hollow motor shaft 86 rotatably held in the housing 74, and a motor. A permanent magnet 88 is disposed on the outer periphery of the shaft 86 so as to face the stator coil 84 and be fixed on one circle. The electric motor 70 is a motor in which the stator coil 84 functions as a stator and the permanent magnet 88 functions as a rotor, and is a three-phase DC brushless motor.

  The speed reducer 72 includes a wave generator 90, a flexible gear (flex spline) 92, and a ring gear (circular spline) 94, and includes a harmonic gear mechanism. The wave generator 90 is configured to include an elliptical cam and a ball bearing fitted on the outer periphery thereof, and is fixed to one end of the motor shaft 86. The flexible gear 92 has a cup shape in which the peripheral wall portion can be elastically deformed, and a plurality of teeth are formed on the outer periphery on the opening side of the peripheral wall portion. The flexible gear 92 is connected to and supported by the right stabilizer bar member 22 described above. More specifically, the right stabilizer bar member 22 passes through the motor shaft 86, and at the end portion extending from the motor shaft 86, the right stabilizer bar member 22 cannot be relatively rotated by serration fitting with the bottom portion of the flexible gear 92 serving as the output portion of the speed reducer 72. They are connected so that they cannot move relative to each other in the axial direction. The ring gear 94 is generally formed in a ring shape and has a plurality of teeth (a slightly larger number than the number of teeth of the flexible gear, for example, two more) than the number of teeth of the flexible gear, and is fixed to the housing 74. The flexible gear 92 has a peripheral wall that is externally fitted to the wave generator 90 and is elastically deformed into an elliptical shape. The flexible gear 92 meshes with the ring gear 94 at two positions located in the major axis direction of the ellipse and does not mesh at other positions. It is said that. When the wave generator 90 makes one rotation (360 degrees), that is, when the motor shaft 86 of the electric motor 70 makes one rotation, the flexible gear 92 and the ring gear 94 are relatively rotated by the difference in the number of teeth.

  From the above configuration, when a vehicle turns or the like, a force that relatively changes the distance between one of the left and right wheels 16 and the vehicle body and the distance between the other of the left and right wheels 16 and the vehicle body, that is, a roll moment acts on the vehicle body. The force that relatively rotates the right stabilizer bar member 22 and the left stabilizer bar member 24, that is, the external input to the actuator 30 acts. In that case, the actuator 30 is driven by a motor force that is a force generated by the electric motor 70 (because the electric motor 70 is a rotary motor and can be considered as a rotational torque, and may be hereinafter referred to as a rotational torque). When the force balanced with the external input is exerted as the actuator force, one stabilizer bar 20 constituted by the two stabilizer bar members 22 and 24 is twisted. The elastic force generated by this twist becomes a force that opposes the roll moment, that is, a roll restraining force. Even if the vehicle body receives the same roll moment, the actuator force is changed by the motor force to change the relative rotation force of the right stabilizer bar member 22 and the left stabilizer bar member 24. As a result, the operation amount of the actuator 30 which is a position where the roll moment and the actuator force are balanced changes. That is, the relative rotational positions of the left and right stabilizer bar members 22 and 24 change, and the roll amount of the vehicle body can be changed. The stabilizer device 14 is thus a device capable of changing the apparent rigidity of the stabilizer bar 20, that is, the stabilizer rigidity.

  The actuator 30 is provided with a motor rotation angle sensor 100 in the housing 74 for detecting the rotation angle of the motor shaft 86, that is, the rotation angle of the electric motor 70. The motor rotation angle sensor 100 mainly includes an encoder in the actuator 30, and the relative rotation angle (relative rotation position) of the left and right stabilizer bar members 22, 24, in other words, the operation amount of the actuator 30, that is, the rotation amount. As an index, it is used for a single wheel stand-up countermeasure process, which will be described later.

  As shown in FIG. 1, electric power is supplied from the battery 102 to the electric motor 70 included in the actuator 30. The present stabilizer system 10 is provided with a DC-DC converter 103 for boosting the voltage supplied by the battery 102, and a power source is configured including the battery 102 and the converter 103 (in the figure, “BAT”, “CNV”). Between the converter 103 and each of the two stabilizer devices 14, a stabilizer electronic control unit (hereinafter may be simply referred to as “stabilizer ECU”) 111 is provided. The stabilizer ECU 111 includes an inverter 104 as a drive circuit and a controller 110 as a control device (indicated by “INV” and “CONT”, respectively). Electric power is supplied to the electric motor 70 included in each of the two stabilizer devices 14 via the inverter 104 included in each of the two stabilizer ECUs 111. Since the electric motor 70 is driven at a constant voltage, the amount of supplied power is changed by changing the amount of supplied current, and the electric motor 70 exhibits a force corresponding to the amount of supplied current. Incidentally, the amount of supply current is performed by the inverter 104 changing the ratio (duty ratio) between the pulse-on time and the pulse-off time by PWM (Pulse Width Modulation).

  Referring to FIG. 1, the controller 110 of the stabilizer ECU 111 is mainly composed of a computer having a CPU, a ROM, a RAM, and the like. The controller 110 includes the motor rotation angle sensor 100 and a steering wheel. An operation angle sensor 120 for detecting an operation angle of the steering wheel, which is an operation amount of the steering operation member as a quantity, a vehicle speed sensor 122 for detecting a traveling speed of the vehicle (hereinafter sometimes abbreviated as a vehicle speed), A lateral acceleration sensor 124 for detecting an actual lateral acceleration that is actually generated in the vehicle body is connected (indicated by “θ”, “δ”, “v”, and “Gy”, respectively). ) Further, the controller 110 is connected to the inverter 104 in the stabilizer ECU 111, and the controller 110 controls the actuator force generated by the actuator 30 by controlling the inverter 104.

(B) Operation mode of electric motor As shown in FIG. 4, the electric motor 70 is a Δ-connected three-phase DC brushless motor, and the inverter 104 has a high side for each phase (U, V, W). Two switching elements UHC, ULC, VHC, VLC, WHC, WLC connected to the input terminals on the (high potential side) and low side (low potential side) are provided. Controller 110, the electric motor 70 to the provided three Hall elements H _A, H _B, to determine the rotational phase (electrical angle) by the detection signal of the H _C, and outputs a control signal based on the rotational phase . According to the control signal, ON / OFF switching of each of the six switching elements is executed. In the present stabilizer system 10, by changing the ON / OFF switching mode of the switching element of the inverter 104, the electric motor 70 is switched between energization / non-energization states between the input terminals of each phase of the electric motor 70 and the power source. The operation of the electric motor 70 is controlled by changing the power supply state. Specifically, in this stabilizer system 10, three operation modes described below are set according to the switching mode of the switching elements and the power supply state, and the electric motor 70 is selected from these three operation modes. The operation is performed in one operation mode selected based on the set condition or the like.

i) Control mode The “control mode”, which is one of the three operation modes, is an operation mode in which the power supplied to the electric motor 70 is controlled under an energization mode in which the operation of the electric motor 70 can be controlled. It is an operation mode in which the device 14 can actively control the roll restraining effect of the vehicle body, for example, according to the roll moment or the like, by generating the roll restraining force according to the roll moment and changing the stabilizer rigidity. . In this control mode, the switching elements UHC, ULC, VHC, VLC, WHC, and WLC are switched on / off according to the rotational phase of the electric motor 70 by a so-called 120 ° energizing rectangular wave drive. Specifically, the energized phase is switched every 60 ° electrical angle. In the control mode, the energized phase switching pattern is set in two patterns according to the direction in which the motor force is generated, that is, the direction in which the rotational torque is generated. The direction of torque generation of the electric motor 70 is determined, and the roll suppressing force in the direction corresponding to the direction is exhibited. In this control mode, only the switching elements ULC, VLC, WLC existing on the low side are subjected to ON / OFF control according to the duty ratio, that is, duty control is performed. By changing, the amount of current supplied to the electric motor 70 is changed.

  As described above, the control mode is a mode in which the direction of torque generation of the electric motor 70 and the amount of electric power supplied to the electric motor 70 can be controlled. In this mode, the electric motor 70 has a supply current amount in an arbitrary direction. It is possible to generate a rotational torque of an arbitrary magnitude according to the above. Therefore, under this control mode, it is possible to control the stabilizer device 14 that actively changes the roll suppression force according to the roll moment.

ii) Brake mode “Brake mode”, which is another one of the three operation modes, is a kind of operation mode in which the inverter 104 does not supply electric power to the electric motor 70. In this mode, each phase of the electric motor 70 is connected to each other. That is, all of the switching elements arranged on one of the high side and the low side are kept in a closed state, and all those arranged on the other of the high side and the low side are kept in an open state. Specifically, in this embodiment, all of the high-side switching elements UHC, VHC, WHC are turned on (closed state), and all of the low-side switching elements ULC, VLC, WLC are An OFF state (open state) is set. Due to the switching elements UHC, VHC, WHC being turned on, the phases of the electric motor 70 are short-circuited with each other. In such a state, a so-called short-circuit braking effect is obtained for the electric motor 70. Therefore, when the actuator 30 is forced to operate at a high speed by an external input, a relatively large resistance (a kind of actuator force) is generated. In this case, the stabilizer device 14 is as if the stabilizer rigidity is increased. It becomes a state close to a normal stabilizer device that cannot be changed. However, since the resistance is small for slow speed operation, even if there is a separation distance between the left and right wheels and the vehicle body, the change speed of the separation distance difference is small, for example, the vehicle is stationary. Or in the state close | similar to stillness, the stabilizer bar 20 hardly exhibits a stabilizer force.

iii) Free mode “Free mode”, which is the remaining one of the three operation modes, is an operation mode in which the inverter 104 does not supply electric power to the electric motor 70 as in the brake mode. In this mode, an energization mode in which energization to each phase of the electric motor 70 is interrupted is set. Specifically, all of the switching elements UHC, ULC, VHC, VLC, WHC, and WLC are turned off (open state). As a result, it is almost as if the connection between each phase of the electric motor 70 and the inverter 104 is disconnected, and the electrical continuity between the input terminals of each phase is cut off. In this operation mode, no electromotive force is generated in the electric motor 70 and the braking effect by the electric motor 70 is hardly obtained. Therefore, if this operation mode is adopted, the stabilizer bar 20 will be in a state in which it can hardly exhibit rigidity, and the vehicle will be in a state in which the stabilizer is not provided.

(C) Stabilizer control
i) Basic control In the present stabilizer system 10, when the roll moment by turning is acting on the vehicle body, the operation mode of the electric motor 70 is set to the control mode, and the roll moment is determined according to the roll moment. Active control for causing the stabilizer device 14 to exert a stabilizer force that counteracts the above is executed. On the other hand, when the roll moment is not substantially applied, the operation mode of the electric motor 70 is set to the brake mode, and the brake control for suppressing the rotation of the actuator 30 is executed. In addition, this stabilizer system 10 is provided with two stabilizer devices 14 on the front wheel side and the rear wheel side, and these two stabilizer devices 14 are individually controlled according to the set roll rigidity distribution, and each of them is controlled. Under the control, each generates a predetermined roll restraining force. In the following description, unless otherwise noted, the two stabilizer devices 14 have the same configuration in consideration of simplification of the description. We will treat them as a single unit.

The active control will be described in detail. In the active control, the controller 110 determines the target actuator force of the actuator 30 to obtain an appropriate stabilizer force based on the lateral acceleration as the roll moment index amount. The electric motor 70 is controlled so as to exert a motor force corresponding to the actuator force. Specifically, first, a controlled lateral acceleration that is a lateral acceleration used for control based on the estimated lateral acceleration Gyc estimated based on the steering wheel operating angle and the vehicle speed and the actually measured actual lateral acceleration Gyr. The acceleration Gy * is determined according to the following equation.
Gy * = K ₁ · Gyc + K ₂ · Gyr (K ₁ , K ₂ : gain)
Next, the target actuator force is determined based on the control lateral acceleration Gy * determined in this manner, and the target supply current i * to the electric motor 70 is determined based on the target actuator force. A command relating to the determined target supply current i * is issued from the controller 110 to the inverter 104, and appropriate power is supplied to the electric motor 70 of the actuator 30 by the inverter 104 so that the actuator 30 exerts the target actuator force. .

ii) One-wheel standing countermeasure processing When the vehicle enters a bad road such as a mogul road, the stabilizer system 10 causes the vehicle to stand on one wheel, for example, as shown in FIG. It becomes a state. It can be said that this one-wheel standing state is a state in which the balance of the load on the left and right wheels is greatly broken. When a set amount of actuator force is applied for a set time, the relative displacement of the wheel-to-vehicle distance is approximately the same regardless of the direction of the actuator force when the load is balanced. In a state in which is greatly collapsed, the direction of the actuator force varies. Specifically, in a single wheel standing state, as shown in FIG. 6, the lower arm 44 on either the left or right wheel side is in contact with the bound stopper 50 or the rebound stopper 52 (the left wheel side in the figure is shown). The lower arm 44 is in contact with the bound stopper 50. In this state, if a certain amount of actuator force is exerted in both directions sequentially for a set time, the lower arm 44 will contact the bound stopper 50. The amount of relative displacement differs between when the actuator force is exerted in a direction that further bounces the contacting side, and when the actuator force is exerted in the opposite direction.

  The difference in the relative displacement amount of the distance between the wheel bodies appears as a difference in the operation amount of the actuator 30 that indicates the relative displacement amount. Therefore, in the present stabilizer system 10, the difference is used, and the threshold value has the difference. If it exceeds the limit, it will be recognized as being in a single-wheeled state. And in this stabilizer system 10, when it is recognized that the vehicle is in a single wheel standing state, the actuator 30 is applied with an actuator force so as not to exert the stabilizer force for the purpose of improving the running performance on a rough road. Actuator neutralization state realization processing is executed so as not to exhibit. Specifically, the free motor is operated in which the operating mode of the electric motor 70 is set to the free mode and the rotation of the actuator 30 by the external input is allowed in a state where the stabilizer device 14 hardly exhibits the stabilizer force. In addition, when one wheel standing state is recognized for one stabilizer device 14 on the front wheel side and the rear wheel side, both the stabilizer devices 14 on the front wheel side and the rear wheel side do not exhibit the actuator force.

(D) Stabilizer control program As a rule, the stabilizer device 14 is controlled by a short time pitch (when the ignition switch is turned on by the controller 110 of the stabilizer ECU 111 according to the stabilizer control program shown in the flowchart of FIG. For example, it is performed by being repeatedly executed at several m to several tens msec). Hereinafter, the control process according to the stabilizer control program will be described in detail with reference to a flowchart.

In the control process according to the stabilizer control program, first, the vehicle speed v and the operation angle δ are acquired in step 1 (hereinafter simply referred to as “S1”. The same applies to other steps) and S2, and then in S3. The estimated lateral acceleration Gyc is estimated based on the vehicle speed v and the operation angle δ. The controller 110 stores map data related to the estimated lateral acceleration Gyc using the vehicle speed v and the operation angle δ as parameters, and the estimated lateral acceleration Gyc is estimated by referring to the map data. Subsequently, in S <b> 4, the actual lateral acceleration Gyr, which is the lateral acceleration actually generated in the vehicle body, is acquired based on the detection value of the lateral acceleration sensor 124. In subsequent S5, the control lateral acceleration Gy * is determined from the estimated lateral acceleration Gyc and the actual lateral acceleration Gyr as described above. Next, in S6, it is determined whether or not the absolute value of the control lateral acceleration Gy * is greater than the threshold value Gy * ₀ . If the absolute value of the control lateral acceleration Gy * is larger than the threshold value Gy * _0, it is determined that the vehicle is turning, and the target supply current i * is determined based on the control lateral acceleration Gy * in S7. Is done. The controller 110 stores map data of the target supply current i * using the control lateral acceleration Gy * as a parameter. In S7, the target supply current i * is determined with reference to the map data. Next, in S8, a command relating to the target supply current i * is output to the inverter 104, the flag _FBR is set to 0 in S9, and one execution of this program is completed. The flag F _BR is set to 1 when brake control is executed as will be described later, and is set to 0 when active control is executed as in the current program execution. .

On the other hand, if the absolute value of the control lateral acceleration Gy * is less than or equal to the threshold value Gy * ₀ in the determination of S6, it is determined that the vehicle is not turning, and in S10, whether or not the one-wheel standing countermeasure program is interrupted is determined. It is determined whether or not the indicated flag F _WK is 0. The flag F _WK has an initial value of 0, and is a value of 1 when processing by a one-wheel stand-up countermeasure program to be described later is substantially performed. As long as the flag F _WK is 1, The brake control is not executed, S11 and S12 are skipped, and one execution of this program is completed. The control of the stabilizer device 14 in this case is executed by a one-wheel stand-up countermeasure program. On the other hand, if the flag F _WK is 0, next, in S11, a process of outputting a command to the inverter 104 is executed so as to execute the brake control. Subsequently, in S12, the flag F _BR indicating that the brake control has been executed is set to 1, and one execution of this program is completed. The flag F _BR is set to 1 until the first active control is executed after the brake control is executed once. In other words, the flag F _BR is set to 1 while the running state of the vehicle is a state where the brake control should be executed. It is said.

(E) One-wheel stand-up countermeasure program The single-wheel stand-up countermeasure process is performed by the above-described stabilizer control while the ignition switch is turned on by the controller 110 of the stabilizer ECU 111. In parallel with the program, in principle, it is performed by being repeatedly executed at a short time pitch (for example, several m to several tens msec). Hereinafter, the single wheel stand-up countermeasure processing will be described in detail with reference to the flowchart shown in the drawing.

First, in S21 and S22, it is determined whether or not the single wheel stand-up countermeasure process should be executed. Specifically, when the vehicle speed v is larger than the threshold value v ₁ or when the flag F _BR indicating that the brake control is being executed by the stabilizer control program is 0, that is, the determination of either S21 or S22. Is NO, it is recognized that the one-wheel standing countermeasure processing should not be executed, and in S23, various parameters, flag Fθ ₀ , flag Fθ _D , flag F _WK , flag F _CW and time counter t _CW , t All _CCWs are initialized and one execution of this program ends. The one-wheel stand-up countermeasure processing is executed only when the vehicle is not running or can be regarded as not running, and if the vehicle starts running even during the processing, The processing is interrupted and all parameters are initialized.

On the other hand, when both the determinations of S21 and S22 are YES, that is, when the vehicle speed v is equal to or less than the threshold value v ₁ and the flag F _BR is 1, the one-wheel standing countermeasure processing should be executed. In the subsequent S24 to S26, the pre-processing motor rotation angle θ ₀ that is the motor rotation angle before the actuator 30 exerts the actuator force is acquired. The pre-processing motor rotation angle θ ₀ is obtained only when the first program is executed when one single-wheel standing countermeasure process is executed. Specifically, in S24, whether the flag F.theta. ₀ is 0 is determined. The flag Fθ ₀ is set to ₀ when the pre-processing motor rotation angle θ ₀ is not acquired in the current one-wheel stand-up countermeasure processing, and when the flag Fθ ₀ is 0, next in S25, The motor rotation angle is acquired as the pre-processing motor rotation angle θ ₀ . In the subsequent S26, the flag Fθ ₀ is set to 1, and thereafter, while this one-wheel stand-up countermeasure process is continuously executed, S25 and S26 are skipped when this program is executed.

Next, in S27, whether the flag F.theta. _D is 0 is determined. Flag F.theta. _D is the initial value is a 0, a 1 and the value to be when the motor rotation angle difference theta _D is acquired for determining whether a one wheel standing state. The flag F.theta. _D in the execution of this program is assumed to be 0, then in S28, the flag F _WK described above is one. Next, in S29, it is determined whether or not the flag _FCW is 0. The flag F _CW is a motor rotation angle that exhibits the actuator force in the CW direction and indicates the operation amount of the actuator 30 in that case in the process of acquiring the actuator force in both directions to acquire the operation amount of the actuator 30. This value is set to 1 when the process of acquiring the right motor rotation angle θ _CW is completed. If the process of acquiring the right motor rotation angle θ _CW is not completed, the determination in S29 is YES, and in the subsequent S30, the preset supply current i _CW that is set in advance to exert the actuator force in the CW direction is determined. Processing for outputting the command to the inverter 104 is performed. In S31, 1 is added to the time counter t _CW . The time counter t _CW indicates the time during which the actuator force is exerted in the CW direction, and specifically indicates the number of times the process of S30 has been executed. Note that, instead of the time counter t _CW , a timer may be used to add the program execution time Δt each time the process of S30 is executed.

Next, in S32, it is determined whether or not the value of the time counter t _CW is larger than the threshold value T _CW . While the value of the time counter t _CW is equal to or less than the threshold value T _CW , the determination in S32 is NO, and it is recognized that the control for exerting the actuator force in the CW direction is not completed, and this program is executed once. Ends. While conditions for executing the one-wheel standing countermeasure processing such as the running state of the vehicle are maintained, the processing of S21 to S32 is repeatedly executed. If it is determined in S32 that the value of the time counter t _CW is greater than the threshold value T _CW, it is determined that the actuator force set in the CW direction has been exerted for a set time, and in S33, the above processing of the motor rotation angle at that time is determined. The displacement with respect to the front motor rotation angle θ ₀ is acquired as the right motor rotation angle θ _CW . Next, in S34, the flag F _CW is set to 1, and the processing of S30 to S34 is skipped in the next execution of this program.

Next, in S35, a command related to a set supply current i _CCW (the same current value as the set supply current i _CW and the flow direction is opposite) set in advance to exert the actuator force set in the CCW direction. Is output to the inverter 104. In the subsequent S36, 1 is added to the time counter t _CCW as in S31. In S37, the same determination as in S32 is performed, and while the value of the time counter t _CCW is smaller than the threshold value T _CCW , the processes of S35 and S36 are repeatedly executed. If it is determined that the value of the time counter t _CCW is greater than the threshold value T _CCW, it is determined that the actuator force set in the CCW direction has been exerted for the set time, and then in S38, before the above processing of the motor rotation angle at that time point A displacement amount with respect to the motor rotation angle θ ₀ is acquired as the left motor rotation angle θ _CCW . Incidentally, the right motor rotation angle θ _CW and the left motor rotation angle θ _CCW are values indicating the amount of displacement from the pre-processing motor rotation angle θ _0, and are treated as positive values regardless of the rotation direction.

In the processing according to this program, the time for supplying the set supply currents i _CW and i _CCW is managed by the time counter t _CW , but instead of such a method, for example, it is also possible to manage using a timer. Is possible. In the processing according to this program, the time for supplying the set supply currents i _CW and i _CCW is such that the right motor rotation angle θ _CW and the left motor rotation angle θ _CCW hardly change when these currents are supplied, that is, In this case, the right motor rotation angle θ _CW and the left motor rotation angle θ _CCW are acquired in the stable state. Instead of such a method, for example, if the supply of the set supply current i _CCW is started after the motor rotation angle returns to the pre-processing motor rotation angle θ ₀ , the state before the stable state is reached. In other words, while the motor rotation angle is changing, it is also possible to acquire the right motor rotation angle θ _CW and the left motor rotation angle θ _CCW , and execute the subsequent processing based on those acquired values. It is also possible to do.

After the right motor rotation angle θ _CW and the left motor rotation angle θ _CCW are acquired, in S39, the absolute value of the difference between the right motor rotation angle θ _CW and the left motor rotation angle θ _CCW is set as the motor rotation angle difference θ _D. Is acquired, and the flag Fθ _D is set to 1 in S40. Thereafter, while the current one-wheel stand-up countermeasure process is continuously executed, that is, until the vehicle speed v is sufficiently increased or the control lateral acceleration Gy * is increased, the processes of S28 to S40 are skipped. The program is executed. Next, in S41, it is determined whether or not the motor rotation angle difference θ _D is greater than the threshold θ _D0 . If the motor rotation angle difference θ _D is larger than the threshold θ _D0 , the vehicle state is recognized as a one-wheel standing state, and a command for executing free control is output to the inverter 104 in S42. Processing is executed. This process is continued until the vehicle traveling speed becomes unsuitable for traveling on a rough road, during which the execution of the above-described stabilizer control program is stopped. Since the process of S42 is such a process, the traveling performance while traveling on a rough road is ensured. On the other hand, if the motor rotation angle difference θ _D is equal to or smaller than the threshold θ _D0 in S41, it is determined that the vehicle is not in a single wheel standing state, and the flag F _WK is set to 0 in S43. When the motor rotation angle difference θ _D is sufficiently small, execution of the stabilizer control program is permitted. This completes one execution of the program.

(F) Functional Configuration of Control Device As shown in FIG. 9, the stabilizer ECU 111, which is a control device of the present stabilizer system 10 that functions by executing the stabilizer control program and the one-wheel stand-up countermeasure program as described above, includes S <b> 1 to S <b> 12. The normal control unit 150 is provided as a functional unit that executes the above-described processing, and the single wheel stand-up countermeasure processing unit 152 is provided as a functional unit that executes the processing of S21 to S43. The single-wheel stand-up countermeasure processing unit 152 includes a specific state including a relative displacement amount difference acquisition unit 154 as a functional unit that executes the processes S24 to S40 and a single-wheel stand-up recognition unit 158 as a functional unit that executes the process of S41 The accreditation unit 156 includes an actuator neutralization state realization unit 160 as a functional unit that executes the processing of S42.

<< Second Embodiment >>
(A) Configuration of Stabilizer System FIG. 10 schematically shows a vehicle stabilizer system 190 that is another embodiment of the claimable invention. Since the present stabilizer system 190 has substantially the same configuration as that of the stabilizer system 10 described above, description of the configuration is omitted. In the following description, common reference numerals are used for components common to the stabilizer system 10. However, the vehicle on which the present stabilizer system 190 is mounted has the vehicle height adjusting device 200, and control related to the vehicle height adjusting device 200 is executed in the control of the stabilizer device 14. ing.

(B) Configuration of Vehicle Height Adjustment Device In a vehicle on which the present stabilizer system 190 is mounted, each suspension device 210 provided corresponding to each wheel 16 has an air spring 214 as a suspension spring. The air spring 214 exhibits a spring force that depends on the air pressure in the air chamber 216, and has a function of changing the separation distance between each wheel 16 and the vehicle body by adjusting the amount of air in the air chamber 216. is doing. In other words, the vehicle height adjustment function for adjusting the vehicle height is provided by adjusting the amount of air in the air chamber 216 of each air spring 214. Roughly speaking, the vehicle height adjusting device 200 that realizes this function includes an air spring 214, a pump device 218 that supplies compressed air to the air chamber 216 of each air spring 214, and a plurality of solenoid valves. And a control valve device 220 for controlling the amount of air in each air chamber.

  More specifically, in the present vehicle height adjusting device 200, the supply passage 230 extends from the discharge port of the pump device 218 and is connected to the common passage 234 common to the four air chambers 216 via the common control valve 232. Yes. The common control valve 232 is a three-position valve. The common passage 234 is connected to the supply passage 230 and connected to the pump device 218, and the exhaust passage 236 is connected to the atmospheric pressure. In addition, the exhaust state and the shut-off state shut off from both the supply passage 230 and the exhaust passage 236 can be selectively realized. Further, four individual passages 238 branch out from the common passage 234 and are connected to the air chambers 216 of the respective air springs 214. Each individual passage 238 is provided with an individual control valve 240. Each individual control valve 240 communicates with the corresponding air chamber 216 in the open state and the common passage 234 to increase or decrease the amount of air in the air chamber 216, and in the closed state shares the air chamber 216 in common. By blocking from the passage 234, the amount of air in the air chamber 216 can be maintained.

  The vehicle height adjusting device 200 includes a vehicle height adjusting electronic control unit (hereinafter sometimes abbreviated as “vehicle height adjusting ECU”) 250 for adjusting the vehicle height by controlling the control valves 232 and 240 described above. Prepare. The vehicle height adjustment ECU 250 is configured mainly by a computer, and is connected to a stroke sensor 252 for detecting the distance between the wheels of each of the four wheels 16 (indicated by “L” in the drawing). . The vehicle height adjustment ECU 250 further includes a vehicle height adjustment switch 254 for the driver to select a LOW state where the vehicle height is low and a HI state where the vehicle height is higher than that state. Connected (indicated by “Sw” in the figure).

(C) Control of Vehicle Height Adjustment Device and Difference in Spring Rate Vehicle height adjustment control, which is control of vehicle height adjustment device 200 configured as described above, is performed by vehicle height adjustment ECU 250 according to a predetermined program. The vehicle height adjustment control is performed so that the vehicle height selected by the vehicle height adjustment switch 254 is realized. Specifically, the pump device 218 and the control valve device 220 are controlled so that the distance between the wheel bodies of each wheel 16 detected by the stroke sensor 252 becomes a distance set according to the vehicle height state. . More specifically, for example, when the vehicle height is changed from the LOW state to the HI state, the pump device 218 is operated, the individual control valves 240 are opened, and the common control valve 232 is supplied with air. State. Then, when the individual control valve 240 corresponding to the wheel 16 in which the distance between the wheel bodies becomes the set distance in the HI state is closed and all the distance between the wheel bodies of the four wheels 16 becomes the set distance, the common control is performed. The valve 232 is shut off and the pump device 218 is deactivated. For example, when the vehicle height is changed from the HI state to the LOW state, the individual control valve 240 is opened and the common control valve 232 is exhausted. The individual control valve 240 corresponding to the wheel 16 in which the distance between the wheel bodies becomes the set distance in the LOW state is closed, and when the distance between all the wheel bodies of the four wheels 16 becomes the set distance, the common control valve 232 is shut off.

  When driving on a rough road is planned, in general, in order to avoid interference between the lower part of the vehicle body and the road surface, the HI state is selected by the driver operating the vehicle height adjustment switch 254, and the vehicle height is reduced. Vehicle height adjustment control for setting the HI state is executed. Conversely, when the rough road traveling is finished, the driver operates the vehicle height adjustment switch 254 to select the LOW state, and the vehicle height adjustment control for setting the vehicle height to the LOW state is executed. Such vehicle height adjustment control is executed on the condition that the vehicle is not traveling or can be regarded as not traveling in order to eliminate the influence of the variation in the distance between the wheel bodies due to the change in the behavior of the vehicle.

  However, in a state where the vehicle is stopped on a road surface with steps on the left and right, the load balance with respect to the left and right wheels 16 is broken, and if vehicle height adjustment control is executed in this state, the left and right wheels Even if the distance between the sixteen wheels is equalized, the air amounts of the air chambers 216 of the two air springs 214 provided corresponding to the left and right wheels 16 are different. In a state where there is such a difference in air amount, the spring rates of the left and right air springs 214 are different from each other. Such a difference in the spring rate affects the behavior of the vehicle. For example, when the vehicle is steered so as to change lanes (lane change), it causes unbalance in the left and right of the behavior of the vehicle.

(D) Processing for Dealing with Spring Rate Difference In the present stabilizer system 190, the stabilizer ECU 111 selectively executes active control and brake control executed by the previous stabilizer system 10 based on the running state of the vehicle, and these active controls. In addition to the brake control, control for dealing with the above-described difference in spring rate is executed.

When the spring rates of the left and right air springs 214 are different, even if a certain amount of stabilizer force is applied, the distance between the wheels and the vehicle body varies depending on the direction of the stabilizer force due to the difference in the spring rate. The amount of variation will be different. This will be described below with reference to FIG. 11 showing the relationship between the change in the distance between the wheels and the body of each air spring 214 and the change in the elastic force. In this figure, for easy understanding, it is assumed that the distance between the left and right wheel bodies is the same value when the actuator force is not generated, and the change in the distance between the wheel body and the elastic force of the air spring 214 is calculated. The relationship with change is shown. As can be seen from the figure, for example, if the actuator force F ₁ in the direction of bouncing the right wheel side and rebounding the left wheel side is exerted, the displacement amount on the right wheel side becomes the magnitude indicated by bB in the figure, and the left wheel side The displacement amount is aRB, and the relative displacement amount of the distance between the left and right wheels is the sum (aRB + bB). In contrast, the same magnitude of the actuator force F ₁ in the opposite direction, i.e., by rebound right wheel side, if exerted in a direction to bounce the left wheel side, displacement of the right wheel side bRB, and the left wheel The side displacement amount is aB, and the relative displacement amount of the distance between the left and right wheels is (aB + bRB). Thus, when the spring rates of the left and right air springs 214 are different, a difference occurs in the relative displacement amount.

  In the stabilizer system 190, a state in which the spring rates of the left and right air springs 214 are different is recognized using the phenomenon in which the difference in relative displacement amount as described above occurs. Specifically, the stabilizer ECU 111 exhibits the set actuator force in both directions for a set time, acquires a relative displacement amount difference that is a difference in relative displacement amount caused by the direction in which the actuator force is exerted, and relative displacement. When the difference in the operation amount of the actuator 30 as the index amount exceeds a set value, it is recognized that the spring rate is different between the left and right air springs 214.

  In the stabilizer system 190, when the spring rate difference state is recognized, the air chambers 216 of the left and right air springs 214 are communicated with each other to realize a state in which the spring rate is equal. Specifically, a command to that effect is output from the stabilizer ECU 111 to the vehicle height adjustment ECU 250, and the vehicle height adjustment ECU 250 that receives the command closes the common control valve 232 and communicates with the air chamber. By opening the individual control valve 240 corresponding to H.216, a process for communicating the left and right air chambers 216 is executed.

(E) Spring rate difference handling program The spring rate difference handling process is performed after the spring rate difference handling program shown in the flowchart of FIG. 12 completes the switching control from the HI state to the LOW state by the vehicle height adjustment control described above. This is performed by being executed by the controller 110 included in the ECU 111. Below, the control process according to a spring rate difference countermeasure program is demonstrated, referring the flowchart shown in a figure. Note that the spring rate difference handling processing may be executed, for example, at another appropriate timing, and is repeatedly executed at an appropriate interval, for example, when the vehicle is not traveling. You may do it.

Since this program has many processes that are common to the above-described one-wheel standing response program, the description of the processing of the one-wheel standing countermeasure program is used for these processes, and a specific description is omitted. First, in S51 and S52, as in S21 and S22, it is determined whether or not the condition for executing the spring rate difference handling process is satisfied. If the determination in S51 or S52 is NO, it is recognized that the spring rate difference handling process should not be executed. In S70, various parameters, flag F _WK , flag F _CW , time counters t _CW , t _CCW Are all set to the initial value 0, and one execution of this program is completed.

On the other hand, if both the determinations in S51 and S52 are YES, it is determined that the spring rate difference handling process should be executed. Next, in S53 to S55, the motor rotation before processing is performed as in S24 to S26. The angle θ ₀ is acquired. In subsequent S56 to S67, as in S28 to S39, a process of obtaining the right motor rotation angle θ _CW and the left motor rotation angle θ _CCW of the electric motor 70 by executing the set actuator force bidirectionally for the set time is executed. Is done. Next, in S68, as in S41, it is determined whether or not the motor rotation angle difference θ _D is larger than the threshold θ _D0 . If the motor rotation angle difference θ _D is greater than the threshold θ _D0 , it is determined that the spring rate is different, and a command for communicating the left and right air chambers 216 is sent to the vehicle height adjustment ECU 250 in S69. Processing to output is executed. On the other hand, when the motor rotation angle difference θ _D is equal to or smaller than the threshold θ _D0, it is recognized that the spring rate is not different, and the process of S69 is skipped. In any case, next, in S70, the flags F _WK and F _CW and the time counters t _CW and t _CCW are returned to the initial value 0, and one execution of this program is completed.

(F) Functional Configuration of Control Device As shown in FIG. 13, the stabilizer ECU 111, which is a control device of the present stabilizer system 190 that functions by executing the stabilizer control program and the spring rate difference handling program as described above, includes S <b> 1 to S <b> 12. The normal control unit 260 is provided as a functional unit that executes the above-described processing, and a spring rate difference handling processing unit 262 is provided as a functional unit that executes the processing of S51 to S70. The spring rate difference handling processing unit 262 includes a relative displacement amount difference acquisition unit 264 as a function unit that executes the processes of S53 to S67, and a spring rate difference recognition unit 268 as a function unit that executes the process of S68. The state recognition part 266 and the spring rate equalization state realization part 270 as a function part which performs the process of S69 are provided.

1 is a schematic diagram showing the overall configuration of a stabilizer system that is a first embodiment of the claimable invention; FIG. It is the schematic which shows the stabilizer apparatus with which the stabilizer system of FIG. 1 is provided. It is a schematic sectional drawing which shows the actuator which comprises the stabilizer apparatus of FIG. It is a circuit diagram which shows typically the inverter which is a drive circuit of the electric motor which the stabilizer apparatus of FIG. 2 has. It is a schematic diagram which shows the state of a suspension apparatus when a vehicle will be in the one-wheel standing state. FIG. 6 is a schematic diagram showing a state where the lower arm of one suspension device is in contact with the bound stopper in the suspension device shown in FIG. 5. It is a flowchart which shows the stabilizer control program performed in the stabilizer system of FIG. It is a flowchart which shows the one wheel stand countermeasure program performed in the stabilizer system of FIG. It is a block diagram which shows the function of the stabilizer electronic control unit which is a control apparatus of the stabilizer system shown in FIG. It is a schematic diagram which shows the whole structure of the stabilizer system which is 2nd Example of claimable invention. 11 is a graph for explaining a state in which the spring rates of the left and right suspension devices are different in a vehicle on which the stabilizer system shown in FIG. 10 is mounted. It is a flowchart which shows the spring rate difference countermeasure program performed in the stabilizer system of FIG. It is a block diagram which shows the function of the stabilizer electronic control unit which is a control apparatus of the stabilizer system of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10: Stabilizer system for vehicles 14: Stabilizer apparatus 20: Stabilizer bar 22: Right stabilizer bar member 24: Left stabilizer bar member 30: Actuator 60: Torsion bar part 62: Arm part 70: Electric motor 72: Reduction gear 74: Housing 104 : Inverter (drive circuit) 111: Stabilizer electronic control unit (stabilizer ECU) (control device) 120: Operating angle sensor 122: Vehicle speed sensor 124: Lateral acceleration sensor 150: Normal control unit 152: One wheel stand-up countermeasure processing unit 154: Relative Displacement amount difference acquisition unit 156: Specific state recognition unit 158: One wheel standing state recognition unit 160: Actuator neutralization state realization unit 190: Vehicle stabilizer system 200: Vehicle height adjustment device 210: Suspension device 214: Air spring 216: Air chamber 250: Vehicle height adjustment electronic control unit (vehicle height adjustment ECU) 260: Normal control unit 262: Spring rate difference handling unit 264: Relative displacement amount difference acquisition unit 266: Specific state recognition unit 268: Spring rate difference Certification unit 270: Spring rate uniform state realization unit

Claims (7)

A stabilizer bar that has both ends connected to each of the wheel holding members that hold each of the left and right wheels, and suppresses the roll of the vehicle body by a stabilizer force that is a force exerted by itself,
An actuator for controlling the stabilizer force by controlling the operation of the stabilizer bar in addition to causing the stabilizer bar to exhibit a stabilizer force corresponding to an actuator force which is a force exerted by itself;
A vehicle stabilizer system comprising: a control device that controls the operation of the actuator;
The control device is
Control of the operation of the actuator so that the set actuator force is sequentially exhibited in both directions for a set time, and a relative displacement index amount indicating the relative displacement amount at both ends of the stabilizer bar at that time The stabilizer system for vehicles which has a relative displacement amount difference acquisition part which acquires the difference by the direction of an actuator force.   2. The vehicle stabilizer system according to claim 1, wherein the relative displacement amount difference acquisition unit acquires a difference in an operation amount of the actuator according to a direction of an actuator force as a difference in the relative displacement index amount.   The control device recognizes that the state of the vehicle on which the stabilizer system is mounted is in a specific state based on the difference in the relative displacement index amount acquired by the relative displacement amount difference acquisition unit. The stabilizer system for vehicles of Claim 1 or Claim 2 which has these. The specific state authorization unit is
When the difference between the relative displacement index amounts is larger than a set threshold value, the one-wheel standing recognition unit that recognizes that the state of the vehicle is in a one-wheel standing state in which the difference in grounding load between the left and right wheels is large. The vehicle stabilizer system of Claim 3 which has these.   The controller includes an actuator neutralization state realizing unit that realizes a state where the actuator cannot exert an actuator force when the vehicle is recognized as being in a single wheel standing state by the single wheel standing recognition unit. 5. The vehicle stabilizer system according to 4. A vehicle equipped with the stabilizer system is a vehicle having an air spring as a suspension spring,
When the specific state recognition unit determines that the difference between the relative displacement index amounts is greater than a set threshold value, the vehicle state indicates that the spring rate of the left and right air springs is caused by the difference in the air amount in the air chamber. The vehicle stabilizer system according to any one of claims 3 to 5, further comprising a spring rate difference recognition unit that recognizes that the spring rates are different from each other. The said control apparatus has a spring rate equal state implementation | achievement part which implement | achieves the state in which the spring rate of the said right and left air springs is equal, when it recognizes that the vehicle is in a spring rate difference state by the spring rate difference recognition part. 7. The vehicle stabilizer system according to 6.

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