JPH04237673A - Attitude controller for steering wheel of vehicle - Google Patents

Abstract

PURPOSE:To suspend the shift of a steering wheel by detecting the a steering wheel of which shift is being suppressed by an obstacle with high precision. CONSTITUTION:The shift position of a steering wheel is detected by a tilt angle sensor 27. During the shift of the steering wheel in a prescribed region, the average value of the conduction electric current of a motor M2 detected by an electric current detector 21 is calculated by a microcomputer 20. The calculated average value and the electric conduction current value of the motor M2 are compared, and the stop judgement of the motor M2 is carried out on the basis of the result of the comparison. Accordingly, the stop judgement standard value of the motor M2 can be set automatically to a proper value corresponding to the variation of the ordinary electric current value of the motor M2.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an attitude control device for controlling the attitude of a steering wheel of a vehicle.

0002

2. Description of the Related Art There is a posture control device that moves a seat and a steering wheel from a driving position to a retracted position and from a retracted position to a driving position when a driver gets in or out of a vehicle.

[0003] In other words, when the driver gets into the vehicle,
As shown in , the seat 32 is rotated toward the door,
The steering wheel 31 is in a state of being flipped upward. When the driver enters the vehicle and closes the door by inserting the key into the key cylinder, for example, the seat 32 rotates and the steering wheel 31 moves downward, allowing the driver to drive as shown in FIG. It becomes a posture.

Furthermore, when the driver turns off the key switch and opens the door, the seat 32 and steering wheel 31 move from the driving position shown in FIG. 8 to the retracted position shown in FIG. 7.

[0005] The driving posture of the seat 32 and the steering wheel 31 can be controlled by, for example, manual switch SW.
It can be set in advance using SW1 to SW4.

[0006] Conventionally, this type of technology was disclosed in Japanese Patent Application Laid-Open No. 62
There is one shown in Japanese Patent No.-39365.

FIGS. 9 and 10 show an example of an overall circuit for controlling the posture of the steering wheel and the seat. FIG. 9 shows the left side portion of the overall circuit, and FIG. 10 shows the right side portion. However, microcomputer M
C and the oscillation circuit OSC are common to both figures.

In FIGS. 9 and 10, PW1 and PW2 are power supply circuits, RSC is a reset circuit, RDC is a failure monitoring circuit, SSC is a standby signal circuit, and IFC is an interface circuit. In addition, ADC is an A/D conversion circuit, RD1, RD2, and RD3 are relay drivers, and CD
1, CD2, CD3, CD4 are overcurrent detection circuits, AM1
are amplifier circuits, RL1, RL2, RL3, RL4, RL5
, RL6 are relays.

The power supply circuit RW1 converts the power of the on-board battery BT into a constant voltage of +5V, the reset circuit RSC generates a reset signal when the power is turned on, and the failure monitoring circuit RD
C generates a reset signal when a pulse signal does not arrive from the microcomputer MC for a predetermined time, and the power supply circuit PW2 generates predetermined voltages Vsb and Vsc.

[0010] The standby signal circuit SSC is a microcomputer MC.
When a standby signal arrives from the microcomputer MC, the microcomputer MC is put into standby mode and the power output of the power supply circuit PW2 is turned off.

The interface circuit IFC generates binary signals depending on the states of various switches.

The oscillation circuit OSC also generates clock pulses to be applied to the microcomputer MC, and relay drivers RD1,
RD2 and RD3 control the two relays connected to them according to instructions from the microcomputer MC, and overcurrent detection circuits CD1, CD2, and CD3 control relays RL1, RL2, RL3, RL4, RL5, and RL6, respectively. The overcurrent detection circuit CD4 detects the overcurrent flowing to the DC motors M1, M2, and M3 through the relay driver RD.
1. Detect overcurrent of RD2 and RD3.

The A/D conversion circuit ADC has five analog input channels, and one of them is selected depending on the states of control terminals C0, C1, and C2. The digital data converted by the A/D conversion circuit ADC is
It is output as a serial signal from the output terminal OUT in synchronization with a clock pulse applied to the terminal CLK. Terminal C
S is chip select.

SSW is a vehicle speed sensor, and the output terminal of this vehicle speed sensor SSW is connected to an external interrupt terminal IRQ of the microcomputer MC via an interface circuit IFC. PSW is a parking switch, and this parking switch PSW opens and closes in conjunction with the parking brake lever.

MSW is a manual away switch that instructs manual away operation. The DSW is a door switch that opens and closes in response to opening and closing of the door. SEL is a selection switch for selecting one of the riding posture conditions in automatic mode, and parking switch PSW,
Either one of the manual away switch MSW and the door switch DSW is connected to the input port P1 of the microcomputer MC via the interface circuit IFC.

KSW is a key switch that opens and closes depending on whether or not an engine key is attached. ASW is an auto switch that specifies whether to enable or disable the automatic getting on/off posture setting mode when getting on/off. REG is a regulator, and this regulator REG stabilizes the output of an alternator coupled to the output shaft of the engine.

[0017] IGS is an ignition switch,
This ignition switch IGS opens and closes in response to the operation of the engine key. When the ignition switch IGS is turned on, power is supplied to the ignition circuit of the engine.

ACCS is an accessory switch, and like the ignition switch IGS, the accessory switch ACCS opens and closes in response to the operation of the engine key. When the accessory switch ACCS is on, the on-vehicle electric circuit other than the engine drive system, that is, the accessory device (not shown) is powered on.

NLS is a neutral switch, which is turned on when the shift lever of the automatic transmission is in the neutral position, and turned off in other positions. P.K.
S is a parking position switch, and this position switch PKS is turned on when the shift lever is in the parking position, and turned off in other positions.

[0020] Motor M1 is a seat drive motor,
Connected to relays RL1 and RL2. Further, motor M2 is a motor for adjusting the tilt angle of steering wheel 31, and is connected to relays RL3 and RL4. Furthermore, the motor M3 is connected to the steering wheel 31
This is a telescopic adjustment motor and is connected to relays RL5 and RL6.

Further, PM1, PM2, PM3 are potentiometers, the potentiometer PM1 is for the seat position, and the potentiometer PM2 is for the steering wheel 31.
The potentiometer PM3 detects the tilt position of the steering wheel 31 and the telescopic position of the steering wheel 31, respectively. The outputs of these potentiometers PM1, PM2, PM3 are supplied to input channels A0, A1, and A2 of the A/D conversion circuit ADC, respectively, via the amplifier circuit AM1.

SW1, SW2, SW3, SW4 are manual attitude setting switches, setting switch SW1 is a switch for tilting up the steering wheel 31, setting switch SW2 is a switch for tilting down the steering wheel 31, and setting switch SW3 is a switch for tilting the steering wheel 31. A telescopic shortening switch 31 and a setting switch SW4 are telescopic extension switches for the steering wheel 31.

One end of each of these manual attitude setting switches SW1, SW2, SW3, and SW4 is connected to each tap of a resistive voltage divider connected to the power supply line, and the other end of each is commonly connected to the amplifier circuit AM1. It is connected to the input channel A3 of the A/D conversion circuit ADC via. Further, the midpoint CP of the resistor voltage divider connected to the output of the battery BT is connected to the input channel A4 of the A/D conversion circuit ADC.

[0024] Therefore, the microcomputer MC selects a predetermined channel and reads the output of the A/D conversion circuit ADC to determine the seat position, the tilt position of the steering wheel, the telescopic position, and the states of the manual attitude setting switches SW1 to SW4. and the output voltage of battery BT can be known.

When the auto switch ASW is on and the battery voltage is normal, the retracted position and driving position of the steering wheel 31 are controlled.

That is, for example, when the key switch KSW and the door switch DSW are turned off, the microcomputer MC determines that there is a possibility that the driver will get in or out of the vehicle. In this case, microcomputer MC controls relay drivers RD2 and RD3.
A command signal is supplied to drive the motors M2 and M3 so that the steering wheel 31 is in the retracted position.

Further, for example, when the key switch KSW and the door switch DSW are turned on, the microcomputer MC determines that there is a possibility that the driver will drive the vehicle. in this case,
Microcomputer MC supplies command signals to relay drivers RD2 and RD3 to drive motors M2 and M3 so that steering wheel 31 is in the driving position.

[0028] In this way, the steering wheel 3
Control of the first retreat posture and driving posture is performed.

In this case, while the steering wheel 31 is moving from the retracted position to the driving position or from the driving position to the retracted position in the tilt angle direction, an obstacle or the like prevents the steering wheel 31 from moving in the tilt angle direction. It is possible that Therefore, it is necessary to detect that movement of the steering wheel 31 is blocked and to stop the motor M2 that drives the steering wheel 31.

Therefore, conventionally, if the current flowing through the motor M2 becomes an overcurrent while the steering wheel 31 is moving, that is, if it exceeds a predetermined value, it is determined that the movement is blocked by an obstacle. Then, motor M2 was stopped.

[0031]

By the way, when the movement of the steering wheel 31 is blocked by an obstacle, especially during the downward movement of the steering wheel 31, it is necessary to protect the steering wheel 31, the motor M2, etc. Therefore, it is necessary to immediately detect this and stop motor M2. Therefore, it is necessary to immediately detect that the current flowing through motor M2 has become an overcurrent.
To this end, it is conceivable to bring the predetermined current value that is determined to be an overcurrent closer to the normal current value of the motor M2.

However, the steering wheel 31 of the vehicle is used in a wide range of temperature conditions from summer to winter, and the load (normal load) of the motor M2 changes due to temperature changes in the viscosity of the grease used in the steering wheel 31. The size also changes depending on the ambient temperature, and the normal current value of motor M2 has a large fluctuation range.

[0033] Therefore, the predetermined current value for determining an overcurrent must be determined in consideration of the above-mentioned variation range of the normal current value, and it is difficult to bring the predetermined current value closer to the normal current value. there were. For this reason, conventionally,
It has been difficult to improve the accuracy of detecting that movement of the steering wheel 31 is blocked.

[0034]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention moves the position of the steering wheel of the vehicle when the vehicle driver gets on and off, as shown in FIG.
A posture control device that controls the posture of a steering wheel includes an electric motor 1 that moves the position of the steering wheel, and a means 2 that detects a current flowing through the electric motor 1.
and means 3 for detecting the moving position of the steering wheel.
Then, the average value of the current flowing through the electric motor 1 is calculated while the steering wheel is moving within a predetermined area within the movable range of the steering wheel, and the calculated average current value and the current current value of the electric motor 1 are compared. , a movement control means 4 that stops the electric motor 1 if the value obtained by subtracting the current average value from the current current value is equal to or greater than a predetermined value.

[0035]

[Operation] The average value of the current flowing through the electric motor while the steering wheel is moving within a predetermined area is calculated. The calculated average value is then compared with the current current value of the electric motor, and based on the comparison result, it is determined whether movement of the steering wheel is blocked by an obstacle. Therefore, this criterion can be automatically set to an appropriate value according to fluctuations in the normal current flowing through the electric motor, and it is possible to detect with high accuracy that movement of the steering wheel is blocked. .

[0036]

Embodiment FIG. 2 is a block diagram of an embodiment of the present invention. Note that the example in FIG. 2 shows only the main parts, and the amplifier, oscillation circuit, potentiometer, etc. in the overall circuit shown in FIGS. 9 and 10 are omitted.

In FIG. 2, 24 is a key switch, 25
is the ignition switch, 26 is the door switch, 27
is a tilt angle sensor (movement position detection means) that detects the tilt angle of the steering wheel. Further, 20 is a microcomputer (movement control means), 22 and 23 are relay drive circuits, RL3 and RL4 are relays, M2 is a motor that moves the steering wheel in the tilt angle direction, and 21 is a current that detects the current flowing through the electric motor M2. It is a detector.

In the above configuration, when the key switch 24 and the door switch 26 are turned on, the microcomputer 20 supplies a command signal to the drive circuit 23 to control the relay RL4 to be switched to the power supply VB side. Then, the steering wheel 31 is moved downward from the retracted position shown by the solid line in FIG. 5 by the motor M2. in this case,
The tilt angle of the steering wheel 31 is detected by the tilt angle sensor 27, the current flowing through the motor M2 is detected by the current detector 21, and the microcomputer 20 controls the attitude of the steering wheel 31 based on these detection signals.

That is, in step 100 of the flowchart shown in FIG. 3, it is determined whether the moving angle θ of the steering wheel 31 from the retracted position is smaller than the set value θs. This set value θs is shown in FIGS. 5 and 6 (
As shown in B), this is a predetermined angular range from the retracted position of the steering wheel 31, and is an angular range in which there is little possibility that an obstacle will come into contact with the steering wheel 31.

If the moving angle θ is less than the set value θs in step 100, the process proceeds to step 101, where it is determined whether a certain period of time has elapsed since the motor M2 was powered on. This fixed time is shown in (A) in Figure 6.
As shown in the figure, when the power is turned on at time t0, a large inrush current flows instantly, so this is set to mask this. This fixed time is defined as the time T1 from time t0 to time t1 at which the current I reaches a steady state.

If the predetermined time T1 has not elapsed, the process proceeds from step 101 to step 104, where α is set to a predetermined value. This predetermined value is a motor overcurrent determination value similar to the conventional one. Then, in step 105, it is determined whether the current motor current is less than or equal to α, and if it exceeds α, the process proceeds to step 106 to stop the motor. If it is less than or equal to α, the process returns to step 100.

Further, in step 101, if a certain period of time has elapsed since the power was turned on, the process proceeds to step 102, and the motor current at that time is stored in a RAM (not shown) or the like. Then, the process proceeds from step 102 to step 103, where "1" is set in the flag FLG. Thereafter, steps 104 and 105 are executed in the same manner as described above, and if the current motor current exceeds α, the motor is stopped.

Steps 100 to 106 described above are repeatedly executed until the movement angle θ becomes equal to or greater than the set value θs (time t2 in FIG. 6B).

When the moving angle θ becomes equal to or greater than the set value θs, the process proceeds from step 100 to step 107, where it is determined whether or not the flag FLG is "1". If not, the process proceeds to step 110, where α is The value is set to a predetermined value and the process proceeds to step 105.

In step 107, if the flag FLG is "1", the process advances to step 108, and step 102
The average value of the motor currents stored in , that is, the average value of the motor currents until the steering wheel 31 moves from the retracted position to the set value θs is determined.

Then, the process proceeds from step 108 to step 109, and the value obtained by adding the margin value β to the obtained average value is set as α. Next, the process proceeds to step 105, where it is determined whether the motor current exceeds α, and if it does, the motor is stopped.
If it has not been exceeded, the process returns to step 100.

Note that the flag FLG is set to the initial state, that is, "0", when the ignition switch 25 is turned on.

Further, when the steering wheel 31 is moved from the driving position to the retracted position, step 100 is performed.
In the initial stage of movement, the movement angle θ is the set value θ
s or more, so step 107 to step 110,
Proceed to step 105. Thereafter, each step is processed in the same manner as described above.

According to the embodiment described above, there is a possibility that an obstacle will come into contact with the steering wheel 31 each time the steering wheel 31 is controlled to move from the retracted position to the driving position (downward). Based on the average motor current value required for movement within a small angular range, it is determined whether movement of the steering wheel 31 is blocked by an obstacle. Therefore, it is possible to accurately detect whether the steering wheel 31 is blocked by an obstacle, regardless of fluctuations in the normal motor current due to changes in ambient temperature.

In the above embodiment, when the steering wheel 31 is within the range of the predetermined angle θs,
Since the motor average current value has not been calculated, a predetermined value is used as a criterion. Also, in this case,
The same predetermined value is used for both the downward movement and the upward movement of the steering wheel 31.

Therefore, it is conceivable to successively average the motor current even when the steering wheel 31 is within the range of the predetermined angle θs, and use the average value as a criterion. Further, upward movement of the steering wheel 31 requires a larger motor current due to the gravity of the steering wheel 31 than downward movement of the steering wheel 31, so the criterion for determining whether an overcurrent is caused is based on downward movement or upward movement. It is possible to do it differently.

FIG. 4 shows the process of the microcomputer 20 that calculates the average value of the motor current even within the range of the predetermined angle θs and uses different criteria for determining whether the steering wheel 31 is moving downward or upward. It is a flowchart.

At step 120 in FIG. 4, it is determined whether the moving angle θ is smaller than the set value θs. If the angle θ is smaller than the set value θs, the process proceeds to step 121, where it is determined whether a predetermined time T1 has elapsed since the power was turned on. If the predetermined time T1 has not elapsed, the process proceeds to step 124, and if the predetermined time T1 has elapsed, the process proceeds to step 122. Then, in step 122, the detected motor current is successively averaged, and the process proceeds to step 123. In step 123, "1" is set in the flag FLG. Next, in step 124, the flag FLG
is “1” or not, and if it is “1”, in step 125, the motor current average value is set to α, and “1” is determined.
”, a predetermined value is set to α in step 126.

The process then proceeds to step 127, in which the steering wheel 31
Determine whether it is in the ascending or descending motion. If the ascending motion is not in progress, α+β′ is set to γ in step 131, and if the ascending motion is in progress, in step 128, α+β′ is set to γ.
+β is set to γ. However, β is a larger value than β'. Next, in step 129, it is determined whether the current motor current is greater than γ. If it is, the motor is stopped in step 130, and if not, the process returns to step 120.

If the moving angle θ is equal to or greater than the set value θs in step 120, the process advances to step 124, and thereafter steps 124 to 131 are processed in the same manner as described above.

As in the example shown in FIG. 4, even when the steering wheel 31 is within the range of the predetermined angle θs, the motor current is successively averaged and the average value is used as a criterion for judgment. Since the determination criterion for movement is set higher than the determination criterion for downward movement, it is possible to accurately detect that the steering wheel 31 is blocked by an obstacle.

[0057]

As described above, according to the present invention, in the attitude control device that moves the position of the steering wheel of the vehicle and controls the attitude of the steering wheel when the driver gets on or off the vehicle, the position of the steering wheel is adjusted. a moving electric motor; a means for detecting the electric power flowing to the electric motor; a means for detecting the moving position of the steering wheel; Movement that calculates the average value of current, compares the calculated average current value with the current value of the electric motor, and stops the electric motor if the value obtained by subtracting the average current value from the current current value is greater than or equal to a predetermined value. Each time the attitude control of the steering wheel is performed, the average current value of the electric motor in a predetermined movement area is used as a criterion for stopping the electric motor. Regardless of the fluctuation, it is possible to accurately detect that movement of the steering wheel is blocked by an obstacle and immediately stop the electric motor.

[Brief explanation of the drawing]

FIG. 1: Complaint correspondence diagram.

FIG. 2 is a block diagram of an embodiment of the invention.

FIG. 3 is an operation flowchart of an embodiment of the present invention.

FIG. 4 is an operation flowchart of another embodiment of the invention.

FIG. 5 is an explanatory diagram of steering wheel attitude control.

FIG. 6 is a diagram showing motor current and tilt angle in steering wheel attitude control.

FIG. 7 is a perspective view of the interior of the vehicle when the steering wheel is in the retracted position.

FIG. 8 is a perspective view of the interior of the vehicle when the steering wheel is in the driving position.

FIG. 9 is a diagram showing a portion of an example of an overall circuit for controlling the attitude of on-vehicle equipment such as a steering wheel.

FIG. 10 is a diagram showing another part of an example of the overall circuit for performing the above attitude control.

[Explanation of symbols]

1, M2...Electric motor 2, 21...Current detector 3, 27...Tilt angle sensor (movement position detection means) 4, 2
0...Microcomputer (movement control means)

Claims (1)

[Claims] Claim 1. An attitude control device that moves the position of a steering wheel of a vehicle and controls the attitude of the steering wheel when a vehicle driver gets on or off the vehicle, comprising: an electric motor that moves the position of the steering wheel; and an electric current flowing through the electric motor. means for detecting the movement position of the steering wheel; and a current calculated by calculating the average value of the current flowing through the electric motor while the steering wheel is moving within a predetermined area within the movable range of the steering wheel. A movement control means that compares the average value with a current value of the electric motor and stops the electric motor if the value obtained by subtracting the average current value from the current current is equal to or greater than a predetermined value. Attitude control device for vehicle steering wheel.