JP2008162313A - Toe angle / camber angle changing device and toe angle / camber angle changing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toe angle/camber angle changing device and method for traveling a vehicle fuel efficiently by reducing loss by positively utilizing turning by imparting a camber angle. <P>SOLUTION: This toe angle/camber angle changing device is provided with a steering angle sensor 18 detecting a steering angle, toe actuators 61 to 64 changing the toe angles of wheels 6 to 9, and camber actuators 65 to 68 changing camber angles of the wheels 6 to 9. The device operates the toe actuators 61 to 64 and the camber actuators 65 to 68 according to the steering angle detected by the steering angle sensor 18. The device is provided with an ECU 5 operating only the camber actuators 65 to 68 in a region in which the steering angle detected by the steering angle sensor 18 is less than a prescribed angle. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a toe angle / camber angle changing device and a toe angle / camber angle changing method for controlling a toe angle and a camber angle when a vehicle turns.

2. Description of the Related Art Conventionally, there has been known one in which wheel alignment is controlled by an actuator in accordance with the running state of a vehicle. There is also a wheel alignment control device that can obtain a desired alignment even if the stroke position of the wheel changes (see Patent Document 1).
JP-A-3-231015

  However, what is described in Patent Document 1 only changes the turning characteristics, and does not consider the energy loss during turning. In order to turn the vehicle, there are cases where a toe angle is given and a camber angle is given, but the cornering force generated at the camber angle is about 1/10 of the cornering force generated at the toe angle. It is turning at the toe angle. However, the cornering force generated at the toe angle is bent by the force component in the direction perpendicular to the tire rotation surface, so the loss is greater than that of camber turning.

  The present invention solves the above-described problem, and a toe angle / camber angle changing device capable of reducing the loss by actively using the turning by giving the camber angle and driving the vehicle with low fuel consumption, and An object is to provide a toe angle / camber angle changing method.

  For this purpose, the present invention comprises a steering angle detecting means for detecting a steering angle, a toe angle changing means for changing a toe angle of a wheel, and a camber angle changing means for changing a camber angle of the wheel, the steering angle detecting means. In the toe angle / camber angle changing device that operates the toe angle changing means and the camber angle changing means according to the detected steering angle, the camber angle is detected in a region where the steering angle detected by the steering angle detecting means is less than a predetermined angle. And control means for operating only the changing means.

  Further, the control means operates only the toe angle changing means in a region where the steering angle detected by the steering angle detecting means is not less than a predetermined angle.

  Furthermore, the present invention provides a toe angle / camber angle changing method for changing a toe angle and a camber angle according to a steering angle, and changes only a camber angle of a wheel in a region where the steering angle is less than a predetermined angle, and in a region where the steering angle is larger than a predetermined angle. Only the toe angle is changed.

  According to the first aspect of the present invention, the steering angle detecting means for detecting the steering angle, the toe angle changing means for changing the toe angle of the wheel, and the camber angle changing means for changing the camber angle of the wheel, In the toe angle / camber angle changing device that operates the toe angle changing means and the camber angle changing means in accordance with the steering angle detected by the steering angle detecting means, a region where the steering angle detected by the steering angle detecting means is less than a predetermined angle. Then, since the control means for operating only the camber angle changing means is provided, the vehicle can be driven with low fuel consumption by actively using the turning by giving the camber angle to reduce the loss.

  According to the second aspect of the present invention, since only the toe angle changing means is operated in a region where the steering angle detected by the steering angle detecting means is a predetermined angle or more, the camber angle changing means and the toe angle changing means are made efficient. The vehicle can be driven with low fuel consumption.

  According to the third aspect of the present invention, in the toe angle / camber angle changing method for changing the toe angle and the camber angle in accordance with the steering angle, only the camber angle of the wheel is changed in a region where the steering angle is less than the predetermined angle. Since only the toe angle is changed in the region above the angle, the vehicle can be driven with low fuel consumption by actively using the turning by giving the camber angle to reduce the loss.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a structure of a vehicle 1 in the present embodiment, and FIG. 2 is a system block diagram of the vehicle 1 in the present embodiment. In the figure, 1 is a vehicle, 2 is a vehicle body, 3 is a battery, 4 is a charger, 5 is an ECU as an example of control means, 5a is a motor controller, 6 to 9 are wheels, 10 is a control system input, and 11 is an accelerator. , 12 is a brake, 13 is a steering wheel, 16 is an accelerator sensor, 17 is a brake sensor, 18 is a steering angle sensor as an example of a steering angle detection means, 20 is a vehicle attitude sensor, 21 is a longitudinal acceleration sensor, and 22 is lateral acceleration. Sensor, 23 is a vertical acceleration sensor, 24 is a roll angular velocity sensor as an example of a roll angle detection means, 25 is a pitch angular velocity sensor, 26 is a yaw angular velocity sensor, 30 is a vehicle motor sensor, 40 is an actuator system sensor, and 41 to 44 are A toe angle sensor as an example of a toe angle detection unit for each wheel, and 45 to 48 are camber angles as an example of a camber angle detection unit for each wheel. An angle sensor, 50 is a driving device, 51 to 54 are wheel motors for each wheel, 60 is a steering actuator, 61 to 64 are toe actuators as an example of toe angle changing means for each wheel, and 65 to 69 are for each wheel. It is a camber actuator as an example of a camber angle changing means.

  The vehicle 1 supports the vehicle body 2 with wheels 6 to 9 via toe actuators 61 to 64 for each wheel and camber actuators 65 to 68 for each wheel, and uses the battery 3 charged by the charger 4 as a power source. The vehicle travels by rotating the motors 51 to 54 and driving the wheels 6 to 9.

  When the occupant executes acceleration of the control system input 10 by the accelerator 11, braking by the brake 12, steering by the steering 13, etc., the values detected by the accelerator sensor 16, the brake sensor 17, and the steering angle sensor 18 are input to the ECU 5. In addition, the vehicle state from the vehicle attitude system sensor 20 such as the acceleration sensors 21 to 23 and the angular velocity sensors 24 to 26, the vehicle motor sensor 30, and the actuator system sensor 40 is input to the ECU 5. The ECU 5 calculates these inputs, and includes the rotational speed of the driving device 50 including the motors 51 to 54, the toe actuators 61 to 64 for each wheel, and the camber actuators 65 to 68 for each wheel via the motor controller 5a. The steering actuator 60 is controlled to control the vehicle body 2 to a desired posture.

  Next, the concept of proper use of changing the toe angle and changing the camber angle in the toe angle / camber angle changing device of the present embodiment will be described. FIG. 3 is a conceptual diagram of proper use for changing the toe angle and changing the camber angle. In the graph, the horizontal axis indicates the steering angle, and the vertical axis indicates the cornering force coefficient.

  In the present embodiment, first, the camber angle is changed until the steering angle reaches a predetermined angle of 25 degrees. This area is a camber angle operation area a. When the steering angle is equal to or greater than the predetermined angle of 25 degrees, the toe angle is changed with the camber angle remaining at an angle corresponding to the steering angle of 25 degrees. This area is a toe angle operation area b.

  FIG. 4 shows a control flow in such a schematic toe angle / camber angle changing apparatus. First, in step 1, the current steering angle operated by the occupant is detected by the steering angle sensor 18 (ST1). The steering angle at this time is memorized and used for the next control. Next, in step 2, the required tow angle and camber angle are calculated by the ECU 5 from the graph, arithmetic expression, map or the like as shown in FIG. 3 (ST2). Subsequently, in step 3, it is determined whether the steering angle operated by the occupant is less than a predetermined value within the camber angle operation region a, for example, less than 25 degrees in this embodiment (ST3).

  If the steering angle is within the camber angle operation region a, it is determined at step 4 whether the steering angle operated by the occupant during the previous control is a value within the camber angle operation region a less than a predetermined value (ST4). Here, when this time is the first control, it is assumed that the previous steering angle is 0 degree, that is, a value within the camber angle operation region a less than a predetermined value.

  If the steering angle operated by the occupant during the previous control is a value within the camber angle operation region a that is less than a predetermined value, in step 5, only the camber angle is operated by the camber actuators 65-68 (ST5). Subsequently, in step 6, the camber angle is detected by the camber angle sensors 45 to 48 (ST6), and in step 7, it is determined whether the target camber angle is reached (ST7). If the target camber angle is reached, the control is terminated. If the target camber angle is not reached, the process returns to step 5.

  If the steering angle operated by the occupant during the previous control is not a value within the camber angle operation area a less than a predetermined value, that is, a value within the toe angle operation area b, as determined in step 4 In step 11, the toe angle is operated by the toe actuators 61 to 64 (ST11). Subsequently, at step 12, the toe angle is detected by the toe angle sensors 41 to 44 (ST12), and at step 13, it is determined whether the target toe angle is reached (ST13). If the target toe angle is not reached, the process returns to step 11. When the target toe angle is reached, next, in step 14, only the camber angle is operated by the camber actuators 65 to 68 (ST14). Subsequently, at step 15, the camber angle is detected by the camber angle sensors 45 to 48 (ST15), and at step 16, it is determined whether the target camber angle is reached (ST16). If the target camber angle is reached, the control is terminated. If the target camber angle is not reached, the process returns to step 14.

  Next, when the determination in step 3 described above is not a value in the camber angle operation region a where the steering angle operated by the occupant is less than a predetermined value, that is, a value in the toe angle operation region b, this embodiment If it is 25 degrees or more, it is determined in step 21 whether the absolute value of the steering angle operated by the current occupant is equal to or smaller than the absolute value of the previous steering angle (ST21). Here, when this time is the first control, the previous steering angle is set to 0 degree. If the absolute value of the steering angle operated by the current occupant is less than or equal to the absolute value of the previous steering angle, the toe angle is operated by the toe actuators 61 to 64 in step 22 (ST22). Subsequently, in step 23, the toe angle is detected by the toe angle sensors 41 to 44 (ST23), and in step 24, it is determined whether the target toe angle is reached (ST24). If the target toe angle is not reached, the process returns to step 21. If the target toe angle is reached, then in step 25, only the camber angle is operated by the camber actuators 65-68 (ST25). However, when it is not necessary to operate the camber angle, the operation amount of the camber angle is set to zero. Subsequently, at step 26, the camber angle is detected by the camber angle sensors 45 to 48 (ST26), and at step 27, it is determined whether the camber angle is the target (ST27). If the target camber angle is reached, the control is terminated. If the target camber angle is not reached, the process returns to step 25.

  If the absolute value of the steering angle operated by the current occupant is not less than or equal to the absolute value of the previous steering angle, that is, if the absolute value of the steering angle operated by the current occupant is greater than the absolute value of the previous steering angle, step 31 Thus, only the camber angle is operated by the camber actuators 65 to 68 (ST31). However, when it is not necessary to operate the camber angle, the operation amount of the camber angle is set to zero. Subsequently, in step 32, the camber angle is detected by the camber angle sensors 45 to 48 (ST32), and in step 33, it is determined whether the target camber angle is reached (ST33). If the target camber angle is not reached, the process returns to step 31. If the target camber angle is reached, the toe angle is operated by the toe actuators 61 to 64 in step 34 (ST34). Subsequently, in step 35, the toe angle is detected by the toe angle sensors 41 to 44 (ST35), and in step 36, it is determined whether the target toe angle is reached (ST36). If the target toe angle is reached, the control is terminated. If the target toe angle is not reached, the process returns to step 34.

  Therefore, when the steering angle operated by the occupant last time is a value within the camber angle operation region a less than a predetermined value, the camber angle is first operated by the camber actuators 65 to 68, and then the steering angle is equal to or greater than the predetermined value. When the value falls within the toe angle operation region b, the toe angle is operated by the toe actuators 61 to 64. When the steering angle operated by the occupant last time is a value in the toe angle operation region b that is equal to or larger than a predetermined value, the toe angle is first operated by the toe actuators 61 to 64, and then the camber whose steering angle is less than the predetermined value. When the value is within the angular operation region a, the camber angle is operated by the camber actuators 65-68.

  As described above, the steering angle sensor 18 that detects the steering angle, the toe actuators 61 to 64 that change the toe angles of the wheels 6 to 9, and the camber actuators 65 to 68 that change the camber angles of the wheels are provided. In the toe angle / camber angle changing device that operates the toe actuators 61 to 64 and the camber actuators 65 to 68 according to the steering angle detected by the sensor 18, the camber is detected in a region where the steering angle detected by the steering angle sensor 18 is less than a predetermined angle. Since the ECU 5 that operates only the actuators 65 to 68 is provided, the vehicle can be driven with low fuel consumption by actively using the turning by providing the camber angle to reduce loss.

It is a figure which shows the vehicle structure of this embodiment. 1 is a block diagram showing a system configuration of a vehicle. It is a figure which shows the toe angle change area | region and camber angle change area | region according to a steering angle. It is a figure which shows the flowchart of the toe angle change according to a steering angle, and a camber angle change.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Vehicle body, 3 ... Battery, 4 ... Charger, 5 ... ECU (control means), 5a ... Motor controller, 6-9 ... Wheel, 10 ... Steering system input, 11 ... Accelerator, 12 ... Brake, DESCRIPTION OF SYMBOLS 13 ... Steering, 16 ... Accelerator sensor, 17 ... Brake sensor, 18 ... Steering angle sensor (steering angle detection means), 20 ... Vehicle attitude system sensor, 21 ... Longitudinal acceleration sensor, 22 ... Left / right acceleration sensor, 23 ... Vertical acceleration sensor 24 ... roll angular velocity sensor (roll angle detection means), 25 ... pitch angular velocity sensor, 26 ... yaw angular velocity sensor, 30 ... vehicle motor sensor, 40 ... actuator system sensor, 41-44 ... toe angle sensor for each wheel (toe angle) Detection means), 45-48 ... camber angle sensor (camber angle detection means) for each wheel, 50 ... drive device, 51-54 ... wheel motor for each wheel, 0 ... steering actuator, 61 to 64 ... the toe actuator for each wheel (the toe angle changing means), 65 to 68 ... camber actuator for each wheel (camber angle changing means)

Claims (3)

  A steering angle detecting means for detecting the steering angle; a toe angle changing means for changing the toe angle of the wheel; and a camber angle changing means for changing the camber angle of the wheel. The steering angle detected by the steering angle detecting means In response, in the toe angle / camber angle changing device that operates the toe angle changing means and the camber angle changing means, a control for operating only the camber angle changing means in a region where the steering angle detected by the steering angle detecting means is less than a predetermined angle. And a toe angle / camber angle changing device.   2. The toe angle / camber angle changing device according to claim 1, wherein the control means operates only the toe angle changing means in a region where the steering angle detected by the steering angle detecting means is not less than a predetermined angle. In the toe angle / camber angle changing method that changes the toe angle and camber angle according to the steering angle, only the camber angle of the wheel is changed when the steering angle is less than the predetermined angle, and only the toe angle is changed when the steering angle is greater than the predetermined angle. A toe angle / camber angle changing method characterized by that.

Images