JPH0610723A - Control device for vehicle with automatic transmission - Google Patents

Abstract

PURPOSE:To improve the starting ability of a vehicle on the slope, which is provided with a fluid type automatic transmission. CONSTITUTION:When a transmission 2 is shifted at a forward gear position (S1), whether or not the vehicles traveling backward is detected (S2). In the case where the traveling backward of the vehicle is detected, a C/U 6 makes an actuator 13 open a throttle valve 7 forcedly (S5) by a value corresponding to the backward acceleration at this stage (S3, S4).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a vehicle provided with an automatic transmission configured to transmit engine output torque via a hydraulic torque converter, and more particularly to improvement of startability on a slope. .

[0002]

2. Description of the Related Art Conventionally, there has been known an automatic transmission configured to transmit engine output torque to a gear type transmission via a fluid type torque converter (Japanese Patent Laid-Open No. Sho 60-60).
256675, etc.). Further, in such a fluid type automatic transmission, it is known that a creep phenomenon that causes the vehicle to gradually move forward in an idle state occurs due to the effect of increasing the torque by the torque converter. In addition, this creep phenomenon has an advantage that the vehicle is prevented from moving backward and the vehicle can be smoothly stopped and started on an uphill road.

[0003]

By the way, on an uphill road with a gentle slope (for example, a slope of less than 15%), even if the operator releases his / her foot from the brake pedal when starting from a state in which the brake pedal is applied to brake, Although the vehicle does not move backward due to the creep phenomenon, it does not move backward,
(15% or more), if the foot is released from the brake pedal, the vehicle may move backward due to insufficient driving torque, and there is a problem that the backward movement at the time of starting gives anxiety to the driver.

When attempting to move the vehicle backward on a downhill, the vehicle may move forward at the time of starting due to the insufficient torque, and in this case also, the driver feels uneasy. The present invention has been made in view of the above problems, and in a vehicle provided with a fluid automatic transmission, it is possible to prevent the vehicle from traveling in a direction opposite to the original traveling direction at the time of starting even on a steep slope. The purpose is to improve the starting performance on slopes.

[0005]

Therefore, a control device for a vehicle with an automatic transmission according to the present invention is configured so that an engine output torque is transmitted to the automatic transmission via a fluid torque converter. Control device of
It is configured as shown in FIG. 1 or 2. In FIG.
The traveling direction detecting means detects the traveling direction of the vehicle, and the traveling gear position detecting means detects that the automatic transmission is shifted to the traveling gear position. In the engine intake air amount increasing means, the traveling gear detecting means detects that the gear position of the automatic transmission is the traveling position, and the traveling direction detecting means moves in a direction different from the direction corresponding to the gear position. When the progress of the vehicle is detected, the intake air amount of the engine is forcibly increased.

On the other hand, in FIG. 2, braking control means is provided in place of the engine intake air amount increasing means, and this braking control means is a traveling gear detecting means and the gear position of the automatic transmission is the traveling position. Is detected and the traveling direction detecting means detects the traveling of the vehicle in a direction different from the direction corresponding to the gear position, the braking device of the vehicle is forcibly operated.

Here, the traveling direction detecting means is rotatably supported by a rotary shaft which rotates in synchronization with the wheels of the vehicle, and a signal plate having a circumferentially asymmetrical uneven portion formed on the circumferential surface, and the signal plate. An electromagnetic pickup that outputs a detection signal according to separation and contact of the uneven portion of the plate, and a waveform shaping that shapes the detection signal from the electromagnetic pickup into a rectangular wave by using two different reference levels for rising and falling. It is preferable to include a circuit and a forward / backward detecting means for detecting forward / backward movement of the vehicle according to the duty ratio of the rectangular wave output from the waveform shaping circuit.

[0008]

According to the control device for a vehicle with an automatic transmission having such a configuration, when the vehicle advances in a direction opposite to the direction corresponding to the traveling gear position of the automatic transmission, the intake air amount of the engine is forcibly increased, Since the output torque of the engine is increased, it is possible to avoid running out of torque even when the vehicle starts on a steep slope, so that it is possible to prevent the vehicle from traveling in the direction opposite to the original direction of travel (downhill). Can be deterred.

Further, if the braking device is forcibly operated when the vehicle travels in the direction opposite to the direction corresponding to the traveling gear position, the driver can operate from the brake pedal when the vehicle starts on a steep slope. Even if the user releases his / her foot, reverse running of the vehicle down the slope due to insufficient torque is braked, and the vehicle can be prevented from traveling in the opposite direction. Further, in a rotation sensor including a signal plate having a concavo-convex portion on its peripheral surface and an electromagnetic pickup that outputs a detection signal in accordance with separation / contact of the concavo-convex portion of the signal plate, the concavo-convex portion is asymmetric in the lateral direction in the circumferential direction If it is formed, the detection signal having a different waveform depending on the rotation direction of the signal plate, in other words, the traveling direction of the vehicle is output from the electromagnetic pickup. Here, when the detection signal is shaped into a rectangular wave, if the reference level used for rising the rectangular wave and the reference level for falling the rectangular wave are different, the traveling direction of the vehicle (forward Alternatively, a rectangular wave having a different duty ratio can be obtained by the backward movement, and the traveling direction of the vehicle can be determined based on the duty ratio.

[0010]

EXAMPLES Examples of the present invention will be described below. In FIG. 3 showing the system configuration of the present embodiment, an automatic transmission 2 is connected to the output side of an engine 1 mounted on a vehicle (not shown). The automatic transmission 2 is connected to a fluid type torque converter 3 interposed on the output side of the engine 1 via the fluid type torque converter 3, and engine output torque is transmitted via the fluid type torque converter 3. Gear type transmission 4 and various friction elements (front clutch, rear clutch, brake band, overrun clutch,
A solenoid valve group 5 is provided for gear shift control, lockup control, line pressure control, engine brake control, etc., for engaging and disengaging lockup clutches and the like.
The solenoid valve group 5 includes a lockup solenoid, a shift solenoid A, a shift solenoid B, an overrun clutch solenoid, a line pressure solenoid, and the like.

Signals from various sensors are input to a control unit 6 which controls the solenoid valve group 5. As the various sensors, there is provided a potentiometer-type throttle sensor 8 for detecting the opening TVO of the throttle valve 7 interposed in the intake system of the engine 1. The throttle valve 7 is configured to be opened and closed by a throttle actuator (for example, a step motor) 13 which is controlled based on a detected value of the depression amount of an accelerator pedal (not shown).

The output shaft of the automatic transmission 2 (rotating shaft that rotates in synchronism with the wheels of the vehicle) is provided with an electromagnetic vehicle speed sensor 9 that emits a pulse signal at every predetermined rotation angle of the output shaft. There is. Based on the operation position signal of the select lever operated by the driver, the control unit 6 refers to a map of a preset shift pattern when the select lever is in the drive range (D range), and opens the throttle valve opening degree. 1st to 4th according to TVO and vehicle speed VSP
The automatic gear shift position is automatically set, and automatic gear shift control is performed to control the gear type transmission 4 to the gear shift position via the solenoid valve group 5.

As shown in FIG. 4, the vehicle speed sensor 9 comprises an electromagnetic pickup 10, a signal plate 11 axially supported by the output shaft of the automatic transmission 2, and a waveform shaping circuit 12. . On the peripheral surface of the signal plate 11,
An asymmetrical saw-toothed concavo-convex portion is formed on the left and right in the circumferential direction, and the electromagnetic pickup 10 is disposed so as to face the concavo-convex portion.
A detection signal corresponding to the contact / separation of the uneven portion with respect to is obtained from the electromagnetic pickup 10.

The detection signal output from the electromagnetic pickup 10 is input to the waveform shaping circuit 12 and shaped into a rectangular wave. The waveform shaping circuit 12 includes a reference level V _ON for raising a rectangular wave and a reference level V _ON for raising a rectangular wave and falling.
It is a circuit that shapes the detection signal into a rectangular wave by comparing _OFF and the detection signal from the electromagnetic pickup 10.

Here, since the uneven portion provided on the peripheral surface of the signal plate 11 has an asymmetric shape in the left and right directions in the circumferential direction, it depends on the rotation direction of the signal plate 11, that is, the traveling direction of the vehicle. Different waveform outputs are obtained from the electromagnetic pickup 10 as shown in FIGS.
Further, in the present embodiment, two different reference levels V _ON and V _ON are used instead of the configuration in which the rectangular wave is raised or lowered based on the fact that the detection signal crosses one reference level.
_The configuration is such that a rectangular wave is formed based on _OFF .

Therefore, as described above, when different waveforms are output from the electromagnetic pickup 10 depending on the rotation direction,
As shown in FIGS. 5 and 6, as a forward / backward detecting means for inputting the rectangular wave output from the waveform shaping circuit 12 as a detection signal of the vehicle speed sensor 9, the duty ratio of the rectangular wave obtained depending on the rotation direction is different. The control unit 6 can detect the duty ratio and detect the traveling direction of the vehicle.

In this embodiment, the traveling direction detecting means is realized by the functions of the signal plate 11, the electromagnetic pickup 10, the waveform shaping circuit 12, and the control unit 6 for obtaining the duty ratio of the rectangular wave. Also,
The shape of the uneven portion of the signal plate 11 is shown in FIG.
It is not limited to the sawtooth shape shown in FIG. The control unit 6 controls the throttle actuator 13 based on the information of the traveling direction of the vehicle which can be determined based on the detection signal from the vehicle speed sensor 9 as described above, regardless of the movement of the accelerator pedal. It has a control function of forcibly controlling it as shown in the flow chart, thereby preventing the vehicle from moving backward when starting on an uphill road.

In the flowchart of FIG. 7, first, in step 1 (denoted as S1 in the figure, the same applies hereinafter),
It is determined whether the gear type transmission 4 is shifted to the forward gear position. This portion corresponds to the traveling gear detecting means. When the gear position is the forward gear, the routine proceeds to step 2, where it is determined whether or not the backward movement of the vehicle is detected based on the duty ratio of the rectangular wave from the vehicle speed sensor 9 as described above.

When the gear position is in the forward gear and the vehicle is moving backward, the vehicle travels in an opposite direction to the original traveling direction corresponding to the gear position due to insufficient drive torque when starting on an uphill road. It can be presumed that it is progressing. In this case, the process proceeds to step 3, and the acceleration of the vehicle in the backward direction is calculated based on the periodic change of the rectangular wave from the vehicle speed sensor 9.

Next, at step 4, the control signal correction value of the actuator 13 for driving the throttle valve 7 in the opening direction is set based on the calculated acceleration in the backward direction. Then, in the next step 5, the actuator 13 is correction-controlled based on the correction value, and the opening of the throttle valve 7 is increased by the correction value compared to the normal opening. That is, the throttle valve 7 (accelerator) is forcibly opened by a predetermined opening degree rather than the normal throttle valve opening degree set based on the depression amount of the accelerator pedal.

In this embodiment, the above step 3,
Parts 4 and 5 correspond to the engine intake air amount increasing means,
As for the hardware configuration, the control unit 6,
The throttle actuator 13 constitutes an engine intake air amount increasing means. In this way, if the throttle valve 7 is forcibly opened, the intake air amount of the engine increases, the output torque increases, and the drive torque for moving the vehicle forward increases. It is possible to prevent the retreat. Therefore, when starting on a steep uphill road,
Even if you release your foot from the brake pedal, the vehicle will not move backward if it slips, and it will be easier to perform a stable start.

If the determination in step 1 is replaced with the shift to the reverse gear position and the determination in step 2 is forward of the vehicle, the vehicle starts to move backward on a downhill (the vehicle is moved backward to move uphill). When the vehicle is made to climb, it is possible to prevent the vehicle from moving forward due to insufficient drive torque by increasing the drive torque in the backward direction.

By the way, in the above embodiment, the accelerator (throttle) is used when the vehicle attempts to move in the direction opposite to the direction corresponding to the gear position (reverse in the forward gear position and forward in the reverse gear position) when starting on a slope. The engine intake air amount is increased by forcibly opening the valve), and thus the engine output torque is increased to suppress it. It may be possible to prevent going to.

That is, as shown in FIG. 3, the control valve 16 for adjusting the supply of the hydraulic pressure generated by the pump 14 to the braking device 15 is constructed so as to be controlled by the control unit 6, and the brake pedal is depressed. Allows the braking device 15 to be actuated by the control unit 6 independently. Then, as shown in the flowchart of FIG. 8, the reverse running of the vehicle at the time of starting on a slope is prevented by operating the braking device 15.

Steps in the flowchart of FIG.
At 11, it is determined whether the transmission is shifted to the forward gear position. This portion corresponds to the traveling gear position detecting means. When the gear position is the forward gear, the process proceeds to step 12 and it is determined whether the vehicle is moving backward.

Then, when the vehicle is in the forward gear position and the vehicle is moving backward, the routine proceeds to step 13, where the hydraulic pressure generated by the pump 14 via the control valve 16 in order to forcibly activate the braking device 15. Is supplied to the braking device 15. Therefore, when the vehicle starts to move backward on a steep slope, the brake is applied when the vehicle tries to move backward when the foot is released from the brake pedal, and the vehicle is prevented from moving backward.

When the braking device 15 is forcibly operated to prevent the vehicle from moving backward, 1 is set in the flag FlagB indicating the operating state of the braking device 15. In the present embodiment, the above step 13 corresponds to the braking control means, and as the hardware configuration, the pump 14, the control valve 16, and the control unit 6 constitute the braking control means.

When the reverse movement is stopped by the operation of the braking device 15, the process proceeds from step 12 to step 14. In step 14, the flag FlagB is determined and the flag FlagB
If 1 is set to, go to step 15,
Whether or not the accelerator pedal is depressed (throttle valve 7
Is opened). When the accelerator pedal is depressed, it is determined that the backward movement can be prevented by increasing the driving torque without activating the braking device 15, the process proceeds to step 16, and the forced operation of the braking device 15 is stopped, The flag FlagB is reset to zero.

When the gear position is shifted to the neutral position or the reverse position, the routine proceeds from step 11 to step 17, the flag FlagB is 1 and the forced braking device 15 is operated to prevent the reverse movement. If so, the routine proceeds to step 18, the forced operation of the braking device 15 is stopped, and the flag FlagB is reset to zero. That is, when the vehicle is trying to move backward due to lack of idle drive torque when the foot is released from the brake pedal at the forward gear position, the braking device 15 automatically operates to brake the backward movement and switch from the brake pedal to the accelerator pedal. If so, it is determined that the driving torque that can prevent the backward movement can be secured, and the forced operation of the braking device 15 is canceled.

Therefore, at the time of starting on a steep uphill road, when the brake pedal is changed over to the accelerator pedal, the vehicle does not slip backward if slippery, and a reliable start can be performed. In the case of the flowchart of FIG. 8 as well, the forward gear position is read as the reverse gear position and the backward is read as forward, so that the idle torque may be insufficient when the vehicle starts moving backward on a downhill (when climbing uphill by moving backward). It is possible to prevent the vehicle from moving forward.

In the above embodiment, as a method of preventing the vehicle from traveling in the direction opposite to the direction corresponding to the gear position, a method of forcibly opening the accelerator (throttle valve) and a braking device
Although the method of forcibly operating 15 is individually shown, the accelerator 15 may be forcibly opened and the braking device 15 may be operated. As means for forcibly increasing the intake air amount of the engine, other than the method of forcibly opening the throttle valve as described above, a control valve for controlling the amount of air supplied by bypassing the throttle valve is used. The opening may be forcibly opened.

[0032]

As described above, according to the present invention, in a vehicle equipped with a hydraulic automatic transmission, when the vehicle is started on a slope, the vehicle is driven in the original traveling direction (to the gear position of the transmission) due to insufficient idle torque. It is possible to prevent the vehicle from proceeding in a direction opposite to the (corresponding direction), and it becomes possible to smoothly start on a steep slope.

[Brief description of drawings]

FIG. 1 is a block diagram showing the basic configuration of the present invention.

FIG. 2 is a block diagram showing the basic configuration of the present invention.

FIG. 3 is a system schematic diagram showing an embodiment of the present invention.

FIG. 4 is a system diagram showing details of a vehicle speed sensor of the embodiment.

FIG. 5 is a time chart showing signal characteristics of a vehicle speed sensor.

FIG. 6 is a time chart showing signal characteristics of a vehicle speed sensor.

FIG. 7 is a flowchart of an embodiment in which the throttle is prevented from reversing.

FIG. 8 is a flow chart of an embodiment for braking and preventing the backward movement.

[Explanation of symbols]

 1 Engine 2 Automatic Transmission 3 Fluid Torque Converter 4 Gear Transmission 6 Control Unit 7 Throttle Valve 9 Vehicle Speed Sensor 10 Electromagnetic Pickup 11 Signal Plate 12 Wave Shaping Circuit 13 Throttle Actuator 14 Pump 15 Braking Device 16 Control Valve

Claims (3)

[Claims] 1. A control device for a vehicle with an automatic transmission configured to transmit an engine output torque to an automatic transmission via a fluid torque converter, the traveling direction detecting means detecting a traveling direction of the vehicle. A traveling gear detecting means for detecting that the automatic transmission is shifted to a traveling gear position; and a traveling gear detecting means for detecting that the gear position of the automatic transmission is a traveling position, and And an engine intake air amount increasing means for forcibly increasing the intake air amount of the engine when the direction detecting means detects the progress of the vehicle in a direction different from the direction corresponding to the gear position. A control device for a vehicle with an automatic transmission characterized by the above. 2. A control device for a vehicle with an automatic transmission configured to transmit an engine output torque to an automatic transmission through a fluid torque converter, the traveling direction detecting means detecting a traveling direction of the vehicle. A traveling gear detecting means for detecting that the automatic transmission is shifted to a traveling gear position; and a traveling gear detecting means for detecting that the gear position of the automatic transmission is a traveling position, and Braking control means for forcibly operating the braking device of the vehicle when the traveling of the vehicle in a direction different from the direction corresponding to the gear position is detected by the direction detection means, And a control device for a vehicle with an automatic transmission. 3. A signal plate in which the traveling direction detecting means is rotatably supported by a rotating shaft that rotates in synchronism with wheels of a vehicle, and a concavo-convex portion that is asymmetric in the circumferential direction is formed on the circumferential surface, and the signal plate. An electromagnetic pickup that outputs a detection signal according to the contact and separation of the concave and convex portions, and a waveform shaping circuit that shapes the detection signal from the electromagnetic pickup into a rectangular wave by using two different reference levels for rising and falling. And a forward / backward detecting means for detecting forward / backward movement of the vehicle in accordance with a duty ratio of a rectangular wave output from the waveform shaping circuit. A control device for a vehicle with an automatic transmission according to any one of claims.