JPS63151539A - Controller for vehicle traveling - Google Patents

Abstract

PURPOSE:To improve brake controlling performance by setting a speed reduction mode with brake control when lateral acceleration G reaches a dangerous region in a vehicle traveling controller so that the speed reduction can be proportionally controlled brake pressure according to lateral G. CONSTITUTION:A vehicle speed signal from a vehicle speed sensor 43 and a lateral G signal from a G sensor 24 are input in a control unit 31. when the lateral G is judged higher than a first reference value to detect a curved road while being less than a second reference value, the vehicle speed at that time is set to set vehicle speed to be stored in RAM 39. Next, when the curved road is being detected at present and a resume switch 29 was turned on, a signal corresponding to a difference between the vehicle speed and the set one stored in RAM 39 is sent to the input of a throttle opening controller 33 to control the vehicle speed. On the other hand, when the switch 29 is turned off, a speed reduction mode is used to operate a brake device 34 and reduce the vehicle speed to predetermined safe speed while releasing the vehicle speed from control. When the lateral G exceeds the second reference value, the vehicle speed is released from control.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a vehicle running control device that can appropriately switch between constant speed running control, deceleration running control, and manual running in response to road conditions. be.

[Conventional technology]

Conventionally, constant-speed driving control devices for vehicles have generally been used only when driving on straight roads in order to ensure safe driving.

FIG. 6 shows a system block diagram of a conventional constant speed cruise control device. In FIG. 6, 43 is a vehicle speed sensor for detecting vehicle speed, 25 is a brake switch activated by brake operation, 27 is a set switch that outputs a set signal by driver operation, and 29 is also activated by driver operation. This is a resume switch that outputs a resume signal.

These vehicle speed sensor 43, brake switch 25, set switch 27, and resume switch 29 are connected to an input/output board 41 of a microcomputer (hereinafter referred to as microcomputer) control unit 31.

Further, the microcomputer control unit 31 outputs an opening control signal to a throttle opening control device 33 that adjusts the opening of a throttle valve (not shown) to control the vehicle speed.

In addition, the microcomputer control unit 31 is a CPU 35° ROM.
37. It is configured to have a RAM 39 and an input/output port 41.

Next, the operation of the conventional constant speed cruise control device will be described.

First, the vehicle speed V is input from the vehicle speed sensor 43 to the microcomputer control unit 31 . When the driver turns on the set switch 27 in this state, the vehicle speed at that time is stored in the RAM 39 as the set vehicle speed v0, and from then on, the own vehicle speed follows this set vehicle speed, and the throttle opening is proportional to the vehicle speed deviation. The throttle opening control device 33 is controlled as follows.

By the way, the conventional device does not have a special sensor for distinguishing between a straight road and a curved road, so if the driver visually determines that it is possible to drive at a constant speed on a substantially straight road, the set switch 27 is activated. was turned on, and the vehicle was traveling at a constant speed using the vehicle speed at that time as the set vehicle speed. Generally, constant speed traveling control is not performed on curved roads.

Further, when the vehicle enters a curved road on a straight road with constant speed driving control set, the constant speed driving control is canceled only by the driver's brake operation.

Furthermore, even on a curved road, if the set switch 27 is operated erroneously, the constant speed cruise control is set, and thereafter the constant speed cruise control cannot be canceled unless the brake is operated as in the case described above.

[Problem that the invention seeks to solve]

That is, in the conventional example, there is no other way to release the fail-safe mechanism other than by operating the brake switch by operating the brake. Therefore, the utilization efficiency as a constant speed cruise control device is poor.

This invention was made in order to solve this problem, and it is possible to switch between constant speed driving control, deceleration driving control, and manual driving control to ensure safe driving. The purpose of the present invention is to obtain a vehicle running control device that can be used on roads and can improve utilization efficiency.

[Means for solving problems]

The vehicle running control device according to the present invention includes: a discrimination means for discriminating between a straight road and a curved road based on the lateral acceleration acting on the vehicle; a control means for controlling the vehicle speed according to the discrimination result of the discrimination means; and a discrimination means. The brake control device is provided with a brake control device that sets the mode to deceleration control mode depending on the detection result.

[For production]

In this invention, when the lateral acceleration exceeds the first reference value, it is determined that the vehicle is traveling on a curved road, and constant speed driving control is performed with the vehicle speed at that time being the target m speed, and the output of the lateral acceleration detection means is set to the first reference value. When the second reference value, which is larger than the reference value of , is exceeded, the brake control device performs deceleration travel control using proportional control in response to the lateral acceleration, and decelerates the vehicle to a safe travel speed.

〔Example〕

Embodiments of the vehicle running control device of the present invention will be described below with reference to the drawings. FIG. 1 is a system block diagram of one embodiment. 1, the difference from the conventional example shown in FIG. 6 is that an acceleration detection device 24 (hereinafter referred to as a G sensor) for detecting the lateral acceleration of the vehicle is used as a determining means for detecting a curved road. is connected to the input port of the microcomputer control unit 31, and a brake control device 34 is newly connected to the output port.

Next, the control action of this invention will be described. First, a vehicle speed signal is input from the vehicle speed sensor 43 to the microcomputer control unit 31, and a lateral G signal is input from the G sensor 24 to the microcomputer control unit 31.

Next, a curved road is detected by determining that the input lateral G is greater than or equal to a preset first reference value, and a determination is made as to whether or not a curved road was detected in the interrupt processing one cycle before. If not, it is determined that the vehicle has just entered a curved road, and if the lateral G of the vehicle exceeds the first reference value and is less than or equal to the second reference value, the vehicle speed V at that time will be described later. This is stored in the RAM 39 as the vehicle speed setting for constant speed driving on a curved road.

Next, if a curved road is currently being detected, it is determined whether or not the resume switch 29 has ever been turned on while traveling on the curved road, and if it has been turned on, the traveling flag is set to "1". ”, and if it remains off, set the running flag to “0”.

However, if the lateral G of the vehicle exceeds the second reference value at the time of these determinations, the running flag is set to "0" regardless of whether the resume switch 29 is on or off.

If no curved road is currently detected, it is determined that the vehicle is traveling on a substantially straight road, and it is determined whether or not the set switch 27 has been turned on while traveling on the straight road. If there is, the running flag is set to "2", and if it remains off, the current value of the running flag is held.

Next, the value of the running flag set by the above processing is checked, and if the running flag is "0", the mode is set to deceleration mode, the brake control device 34 is activated, and the speed is decelerated to a predetermined safe speed. Release vehicle speed control at this point.

In addition, when the running flag is "1", in order to drive at a constant speed at the set vehicle speed v0 stored in the RAM 39, the vehicle speed V and the set vehicle speed v0 are set.
An opening control signal corresponding to the difference between the two is output to the throttle opening control device 33, and if the running flag is "2", the vehicle speed at the time when the set switch 27 is activated is set as the set vehicle speed v0,
Similar to the case described above, an opening control signal is output to the throttle opening control device 33 to control the vehicle speed.

FIG. 2 shows a block diagram of a first embodiment of the brake control device 34 in deceleration traveling control. In FIG. 2, 1 is a wheel, 2 is a brake cylinder, 3 is a brake pedal, and 4 is a master cylinder.

This master cylinder 4 responds to the brake pedal 3, and is provided with a high pressure port 4a and a low pressure port 4b.

The high pressure port 4a is connected to the brake cylinder 2- via a hydraulic conduit 5a1, a two-way solenoid valve 36, and a fixed orifice 54 for absorbing 50% surge in the hydraulic conduit.

The pressure switch 57 is operated by the hydraulic pressure of the hydraulic pipe 55C, and the surge tank 44 is connected to the hydraulic pipe 5c.

On the other hand, the low pressure bow 4b of the master cylinder 4 is connected to a reservoir tank 51 via a hydraulic pipe 5d.

A hydraulic pump 30 is communicated with this reservoir tank 51 via a hydraulic conduit 5g. The discharge side of this hydraulic pump 30 is connected to a hydraulic conduit 5b.

This hydraulic pipe line 5b communicates with the reservoir tank 51 via a two-way solenoid valve 55, and this two-way solenoid valve 55
is connected to the three-way solenoid valve 18 via the hydraulic pipe 5h,
Furthermore, it is connected to the solenoid type variable orifice 23 via a hydraulic pipe 95f.

The hydraulic pipe line 5b is connected to the hydraulic pipe line 5 through a two-way solenoid valve 32.
1, and is also connected to a hydraulic conduit 5f via a two-way solenoid valve 53.

This hydraulic line 51 is connected to the hydraulic line 5C.

On the other hand, the three-way solenoid valve 18 is connected to the cylinder left chamber 20 of the cylinder device 6. A solenoid type variable orifice 22 is connected in parallel to this cylinder device [6.

A spring 8 is provided in the cylinder right chamber 21 of the cylinder device 6, and the piston 7 reciprocates against the elasticity of the spring 8.

This cylinder device 6 is connected to a hydraulic pipe $ through a hydraulic pipe line 5g.
5 Connected to e. Solenoid-type variable orifices 22 and 23 are connected by this hydraulic conduit 5e.

Solenoid coils 22 a and Z 3 a are wound around the solenoid type variable orifices 22 and 23, respectively.

Next, the operation of this brake control device 34 will be explained. In the normal braking state, the two-way solenoid valve 36 is in the on state, so that the master cylinder hydraulic pressure corresponding to the amount of brake depression is applied to the hydraulic line 5a.

It is supplied to the brake cylinder 2 via 5C, and normal braking operation is performed.

In addition, when the brake is off, the high pressure port 4a of the master cylinder 4 is connected to the low pressure port 4b, and the hydraulic pipe 4a is connected to the low pressure port 4b. 15d
It communicates with the reservoir tank 51 via , and the brake operating pressure is released.

Next, in the deceleration running state, the two-way solenoid valve 36 is turned off, the two-way solenoid valve 32 is turned on, and the oil pressure of the hydraulic pump 3° is changed to the oil pressure W! It comes to act on the brake cylinder 2 via $5b and 5c.

The hydraulic pressure in this hydraulic line 5c is detected by a pressure switch 57, and the hydraulic pump 30 is used to pump the reservoir tank 51.
When the oil pressure in the hydraulic pipe 5c reaches a predetermined pressure by pumping up the oil from the hydraulic pipe 5c, the pressure switch 57 is activated to turn off the two-way solenoid valve 32 and divert the hydraulic oil from the hydraulic pump 30 into the hydraulic pipe 5c. be enclosed in.

When the three-way solenoid valve 18 is turned on in this state, the hydraulic pipe $
5c flows into the left cylinder chamber 20 of the cylinder device 6, so that the pressure is reduced corresponding to the internal volume of the left cylinder chamber 20.

Normally, the cylinder left chamber 20 is positioned at an initial position where the volume of the left chamber 20 is minimized by the action of the spring 8.

On the other hand, the cylinder left chamber 20 and the reservoir tank 51 [ni solenoid type variable orifice 22.23 are inserted in series, and from the connection point of both solenoid type variable orifices 22.23 to the cylinder right chamber 21 of the cylinder equipment [6]. They are connected via hydraulic conduit 5g.

Therefore, the hydraulic pressure determined by the diameter ratio of the two solenoid type variable orifices 22 and 23 acts on the cylinder right chamber 21, so that the piston 7 is operated by the pump oil pressure, the repulsive force of the spring 8, and the two solenoid type variable orifices. 22. Stops at the position where the resultant force of the hydraulic pressure at the connection point 23 is balanced.

By the way, in order to increase the brake cylinder operating pressure, it is sufficient to reduce the volume of the cylinder left chamber 20, and for that purpose, both the solenoid type variable orifices 22 and 23
Just increase the oil pressure at the connection point.

For this purpose, the diameter of the solenoid-type variable orifice 23 is narrowed relative to the solenoid-type variable orifice 22, or the diameter of the solenoid-type variable orifice 22 is loosened relative to the solenoid-type variable orifice 23. Such control can be easily performed by controlling the excitation current to the solenoids of these solenoid type variable orifices 22, 23.

Therefore, if the coil current is controlled by increasing the current in the solenoid coil 23a or decreasing the current in the solenoid coil 23b in accordance with the increase in the lateral G, or by the reverse combination of the above, the lateral force direction It is also possible to proportionally control the brake oil pressure P in accordance with G, and the brake control characteristics in this case are shown in FIG.

Further, the surge tank 44 and the fixed orifice 24 are for absorbing the surge pressure generated when the two-way solenoid valves 36, 32, etc. are turned on to obtain a smooth rise.
Reference numeral 3 denotes a pressure relief valve for rapidly removing the residual pressure in the hydraulic line when the brake control is stopped.

Further, the two-way solenoid valve 55 is a short-circuit valve that connects the output port of the logical pressure pump 30 to the reservoir tank 51 when energized, and makes the output pressure zero.

FIG. 3 shows a block diagram of a second embodiment of the brake control device 34 in deceleration traveling control. In FIG. 3, the difference from the first embodiment is that a fixed orifice 22A is used instead of the solenoid variable orifice 22, and the other components are the same as in the first embodiment, so they will not be detailed. Explanation will be omitted.

Next, the operation of this brake control device will be explained.

Since the operation in this case is almost the same as that in the first embodiment, only the main points will be described.

Now, in order to increase the brake pressure in a state where pump hydraulic oil is sealed in the hydraulic pipe line 5C, it is possible to increase the brake pressure by narrowing the diameter of the solenoid type variable orifice 23 with respect to the fixed orifice 22A, and also, The brake pressure can be reduced by loosening the diameter of the solenoid type variable orifice 23 with respect to the fixed orifice 22A.

Therefore, by controlling the current of the solenoid coil 23a of the solenoid type variable orifice 23 with respect to the lateral direction G, it is also possible to proportionally control the brake oil pressure P with respect to the lateral direction G as shown in FIG.

FIG. 4 shows a block diagram of a third embodiment of the brake control device 34 in deceleration traveling control. In FIG. 4, the difference from the first embodiment is that a fixed orifice 23A is used instead of the solenoid variable orifice 23, and the other components are the same as in the first embodiment. Explanation will be omitted.

Next, the operation of this brake control device will be described. Since the operation in this case is almost the same as that in the first embodiment, only the main points will be described.

Now, in order to increase the brake pressure with pump hydraulic oil sealed in the hydraulic pipe 5C, it is possible to increase the brake pressure by loosening the diameter of the solenoid type variable orifice 22 with respect to the fixed orifice 23A. Furthermore, the brake pressure can be reduced by narrowing the diameter of the variable orifice 22 relative to the fixed orifice 21A.

Therefore, by controlling the solenoid coil current of the solenoid type variable orifice 22 with respect to the lateral direction G, it is also possible to proportionally control the brake oil pressure P with respect to the lateral direction G as shown in FIG.

As stated above, the control action of this invention device can be summarized as follows: (1) When traveling on a straight road, constant speed driving control is performed in which the vehicle speed at the time the set switch is operated is set as the vehicle speed.

(2) When the vehicle is traveling on a curved road and the lateral G is less than the second reference value, constant speed driving control is performed in which the vehicle speed at the time when the lateral G exceeds the first reference value is set as the vehicle speed.

(3) When the lateral G exceeds the second reference value while traveling on a curved road, the brake control device is activated, and after decelerating to a predetermined full speed, the traveling control is canceled and the mode is returned to manual mode.

〔Effect of the invention〕

As explained above, in this invention, in addition to the conventional constant speed driving on a straight road, a constant speed driving controllable range is automatically selected even on a curved road, and the degree of the curve is automatically determined based on the lateral G. However, when this lateral G reaches a certain danger range, the system enters a deceleration mode using brake control, and after decelerating to a safe driving speed, the driving control is released and the mode is restored to manual mode. A travel control device with higher safety can be realized.

In addition, since the deceleration control allows proportional control of the brake pressure in response to the lateral G, brake control with improved control performance is possible.

[Brief explanation of the drawing]

FIG. 1 is a system block diagram of one embodiment of the vehicle running control device of the present invention, and FIGS. 2 to 4 are system diagrams showing the configuration of specific embodiments of the brake control device in the vehicle running control device. , FIG. 5 is a brake control characteristic diagram of the above brake control device, and FIG. 6 is a system block diagram of a conventional constant speed control device. 1... Wheel, 2... Brake cylinder, 3... Brake pedal, 4... Master cylinder, 6... Cylinder equipment [, 22, 23... Solenoid type variable orifice, 24.22A, 23A, 54... Fixed orifice, 24... G sensor, 25... Brake switch, 27... Set switch, 29... Resume switch, 30... Hydraulic pump, 31... Microcomputer Control unit, 33... Throttle opening control device, 34
...Brake control device, 35...cpu, °37.
...ROM, 39...RAM141...Input/output boat, 43...Vehicle speed sensor. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (2)

[Claims] (1) Discrimination means for determining whether the traveling path is straight or curved based on lateral acceleration acting on the vehicle, a vehicle speed sensor for detecting vehicle speed, an operation means for outputting an operation signal in response to a driver's operation, and a vehicle. When the vehicle is traveling on a straight road, it enables constant speed travel control at a set vehicle speed, and when the lateral acceleration exceeds the first reference value, it is determined that the vehicle is traveling on a curved road and the vehicle speed at that point is set to the target speed. When the output of the determining means exceeds a second reference value that is larger than the first reference value, deceleration driving control is performed, and after deceleration to a safe driving speed, vehicle speed control is performed. A vehicle traveling system comprising: a vehicle speed control means that can be released and restored to manual mode; and a brake control device that proportionally controls brake pressure in response to lateral acceleration when the vehicle speed control means enters the deceleration travel control mode. Control device. (2) The brake control device applies hydraulic pressure to the brake cylinder corresponding to the amount of brake depression in the normal braking state, and also releases the brake operating pressure by communicating with a reservoir tank that stores pressure oil when the brake is off. A master cylinder, a hydraulic pump that supplies pressure oil in the reservoir tank to the brake cylinder during deceleration driving, and a hydraulic pump that detects the hydraulic pressure of the pressure oil supplied to the brake cylinder and when the detected value exceeds a predetermined value. Accordingly, the hydraulic pump includes a pressure switch for sealing the hydraulic oil of the hydraulic pump in the hydraulic conduit between the hydraulic pump and the brake cylinder, and a means for proportionally controlling the hydraulic pressure of the brake cylinder in response to lateral acceleration. A vehicle running control device according to claim 1.