JP2007132316A - Vehicle controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vehicle controller capable of suppressing the output of a drive force unpredicted by a driver and formed in consideration of the effect of the gradient of road surface. <P>SOLUTION: This vehicle controller comprises a vehicle speed detection means 36 detecting a vehicle speed and a control means 60 determining a throttle valve opening according to an accelerator operation. The control means 60 performs low-speed limit control to limit the throttle valve opening when the vehicle speed detected by the vehicle speed detection means 36 is equal to or less than a predetermined vehicle speed. The vehicle controller further comprises a gradient detection means detecting the gradient of the road surface and a shift position detection means 32 detecting shift positions. The shift position detected by the shift position detection means 32 is the position for advancement. When the gradient of the road surface detected by the gradient detection means is more than the predetermined gradient, the low-speed time limit control is not performed irrespective of the vehicle speed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle control device, and in particular, includes a vehicle speed detection unit that detects a vehicle speed and a control unit that determines a throttle valve opening based on an accelerator operation, and the control unit is detected by the vehicle speed detection unit. The present invention relates to a vehicle control device that performs low-speed limit control for limiting the throttle valve opening when the vehicle speed is equal to or lower than a predetermined vehicle speed.

  Conventionally, especially in an automatic vehicle, when trying to stop the vehicle from moving forward or backward due to a creep phenomenon, the driver's unexpected driving force may be output due to a mistake in pressing the accelerator pedal and the brake pedal. It was.

  On the other hand, as an example of a device mounted on a vehicle with a structure in which the accelerator pedal opening and the throttle valve opening are directly connected mechanically, if the accelerator pedal is strongly depressed during low-speed driving, the brake is What suppresses the influence of this unexpected driving force by operating is known (for example, refer to Patent Document 1).

In addition, there is a known device that restricts the throttle valve opening to be lower than the normal value determined according to the accelerator pedal operation when the accelerator pedal is strongly depressed during low-speed driving (for example, patents). Reference 2).
JP-A-5-178127 JP-A-9-287488

  However, in the device described in Patent Document 1, the output of the driving force and the braking operation are simultaneously performed, which not only increases the manufacturing cost but is not preferable in terms of the durability of the vehicle.

  Further, in the device described in Patent Document 2, the road surface gradient is not taken into consideration. For example, the throttle valve opening is limited at the time of starting on an uphill or traveling at a low speed, thereby allowing the driver to However, the expected driving force may not be output and the vehicle may slide down. This is true even when going backwards downhill.

  SUMMARY OF THE INVENTION The present invention is intended to solve such a problem, and it is a main object of the present invention to provide a vehicle control device that suppresses the output of driving force that the driver does not expect and that takes into consideration the influence of the gradient of the road surface. To do.

  In order to achieve the above object, a first aspect of the present invention includes vehicle speed detection means for detecting a vehicle speed, and control means for determining a throttle valve opening based on an accelerator operation. The control means includes vehicle speed detection. A vehicle control device that performs low-speed limit control that limits the throttle valve opening when the vehicle speed detected by the means is equal to or lower than a predetermined vehicle speed, and detects a road surface gradient and a shift position. A shift position detecting means, wherein the shift position detected by the shift position detecting means is a forward position, and the road slope detected by the slope detecting means is an ascending slope greater than or equal to a predetermined slope. The low speed restriction control is not performed regardless of the vehicle speed.

  According to the first aspect of the present invention, there is basically provided a control means for performing low-speed limit control for limiting the throttle valve opening when the vehicle speed detected by the vehicle speed detection means is equal to or lower than a predetermined vehicle speed. The control means does not perform low-speed limit control regardless of the vehicle speed when the road surface slope is an ascending slope that is equal to or higher than a predetermined slope. Therefore, the control means suppresses unexpected output of the driving force and starts uphill. It is possible to prevent the vehicle from sliding down at the time of traveling at a low speed.

  In the first aspect of the present invention, the shift position detected by the shift position detecting means is a reverse position, and the road surface detected by the gradient detecting means has a slope of a predetermined gradient or more. When it is a gradient, the low speed restriction control may not be performed regardless of the vehicle speed. By so doing, it is possible to prevent the vehicle from sliding down in the downward direction even when traveling backward on a downhill.

  According to a second aspect of the present invention, there is provided a vehicle speed detecting means for detecting a vehicle speed, and a control means for determining a throttle valve opening based on an accelerator operation, wherein the control means detects the vehicle speed detected by the vehicle speed detecting means. A control device for a vehicle that performs low-speed limit control that limits the throttle valve opening when the vehicle speed is equal to or lower than a predetermined vehicle speed, and includes a gradient detection unit that detects a road gradient, and the control unit is detected by the gradient detection unit When the road gradient is equal to or greater than a predetermined gradient, the low-speed restriction control is not performed regardless of the vehicle speed.

  According to the second aspect of the present invention, there is basically provided a control means for performing a low speed limit control for limiting the throttle valve opening when the vehicle speed detected by the vehicle speed detection means is equal to or lower than a predetermined vehicle speed. The control means does not perform low-speed limit control regardless of the vehicle speed when the road surface gradient is equal to or greater than a predetermined gradient, so that the driver suppresses unexpected output of driving force and starts off on a slope or runs at low speed. Occasionally, the vehicle can be prevented from sliding down the road surface.

  In the first or second aspect of the present invention, the control means is preferably means for performing control at low speed by providing hysteresis at a predetermined vehicle speed.

  Moreover, this 1st or 2nd aspect of this invention is provided with the input means which can input the stop of the control at the time of low speed, and the return from this stop by operation of an operator, Preferably. In this case, when the ignition is turned off in the state where the low speed control is stopped by the operation of the input means, it is more preferable to return from the state where the low speed control is stopped.

  ADVANTAGE OF THE INVENTION According to this invention, the control apparatus for vehicles which considered the influence of the gradient of a road surface while suppressing the output of the driving force which a driver | operator does not anticipate can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a diagram illustrating an example of an overall configuration of a vehicle control device 10 according to an embodiment of the present invention. The vehicle control device 10 includes an engine 20, an accelerator position sensor 30 that detects the amount (opening) of an accelerator pedal, a shift position sensor 32 that detects a shift position, and a G sensor 34 that detects vehicle acceleration. , A vehicle speed sensor 36, a throttle valve 40, a fuel injector 45, an input switch 50 capable of instructing on / off of low-speed limit control, which will be described later, by an operator's input, ECU: Electronic Control Unit) 60.

  The engine 20 finally outputs a driving force for traveling to the driving wheels via the CVT by burning fuel such as gasoline.

  For example, the G sensor 34 is a sensor that is attached to the center of the vehicle and outputs a signal corresponding to the magnitude of acceleration acting in the front-rear and left-right directions of the vehicle. The vehicle speed sensor is, for example, a wheel speed sensor attached to the wheel.

  The engine ECU 60 is a computer centered on a CPU, for example, and performs control such as fuel injection control on the engine 20 in accordance with an operation of an accelerator pedal or a brake pedal. Various signals from the above-described sensors are input to the engine ECU 60 via an input port (not shown), and the history of the input signals is stored in a storage medium such as a RAM provided in the engine ECU 60.

  The opening degree of the throttle valve 40 (hereinafter referred to as the throttle valve opening degree) is determined by the engine ECU 60 according to a flow to be described later, and this is transmitted to a motor drive circuit (not shown) provided in parallel with the throttle valve 40. The throttle valve 40 is driven.

  The amount of fuel injected from the fuel injector 45 is determined by the engine ECU 60 based on the throttle valve opening and the theoretical air-fuel ratio. Accordingly, it may be considered that the magnitude of the driving force output from the engine 20 basically increases or decreases according to the throttle valve opening.

  By the way, especially in an automatic vehicle, for example, when trying to stop the vehicle from moving forward or backward due to a creep phenomenon, an unexpected driving force of the driver may be output by mistakenly pressing the accelerator pedal and the brake pedal. Therefore, even in the vehicle control apparatus 10 according to one embodiment of the present invention, at the time of low speed (for example, 5 [km / h] or less), an unexpected upper limit is set for the throttle valve opening. Driving power output is suppressed (hereinafter referred to as low speed limit control).

  However, if the throttle valve opening is limited when starting uphill, the driving force expected by the driver may not be output and the vehicle may slide down. The same is true when going backwards on a downhill.

  Therefore, the vehicle control apparatus 10 according to an embodiment of the present invention does not perform the low-speed limit control in a predetermined case based on the road surface gradient and the shift position. This will be described below.

  FIG. 2 is a diagram illustrating an example of a throttle valve opening determination flow executed by the engine ECU 60. This flow is repeatedly executed every predetermined time (for example, several [msec]).

  First, the CPU of the engine ECU 60 inputs output values from the accelerator position sensor 30, the shift position sensor 32, the G sensor 34, and the vehicle speed sensor 36 (S100).

  Then, based on the accelerator opening, a required throttle opening S1 that is considered to have been requested by the driver by the accelerator operation is derived (S110). This derivation is performed using a dedicated map stored in advance in a storage medium such as a ROM of the engine ECU 60. FIG. 3 shows an example of the required throttle opening setting map. As shown in the figure, the required throttle opening is determined to increase according to the accelerator opening.

  Next, it is determined from the output value from the vehicle speed sensor whether or not the current vehicle speed V is equal to or lower than the speed V1 (S120). The speed V1 is set to a speed of, for example, 5 [km / h] so as to obtain a positive determination in S120 when the vehicle starts or creeps.

  If the vehicle speed V is less than or equal to the speed V1, the throttle limit flag is set to ON (S130). The throttle limit flag is stored in a storage medium such as a RAM of the engine ECU 60 every time the setting is changed. When the vehicle is started (when the ignition is turned on), the initial value is set to ON.

  Then, a signal from the input switch 50 is input, and it is determined whether the input switch 50 is in an on state or an off state (S140). The state of the input switch 50 is set to ON as an initial value when the vehicle is started (when the ignition is turned on).

  If the input switch 50 is in the on state, the road surface gradient is detected or calculated based on the output values from the G sensor 34 and the vehicle speed sensor 36 (S150). This calculation can be performed only by the output value of the G sensor 34 when the vehicle is stopped. However, when traveling, the vehicle speed history from the vehicle speed sensor and the output value of the G sensor may be compared.

  When the slope of the road surface is detected or calculated, (A) it is an uphill with a predetermined slope θ or more and the shift position is a forward position (for example, D, 1, 2, etc.), or (B) It is determined whether or not the vehicle is a downhill with a predetermined gradient θ or more and the shift position is a reverse position (for example, R) (S160, 170). The predetermined gradient can be arbitrarily determined based on the performance of the engine 20 or the like.

  If a negative determination is obtained in any of the above (A) and (B), it is determined that no slippage or the like due to restriction of the throttle valve opening occurs, and the required throttle opening S1 is set to the upper limit value. In step S2, the throttle valve opening S is determined (S180, 190: restriction control at low speed), and one routine of this flow is completed. Here, the upper limit value S2 can be arbitrarily determined, but the driving force output based on the throttle valve opening can be sufficiently handled by the brake operation even if the driver does not intend. It is desirable to set a relatively small value.

  If an affirmative determination is made in any of (A) and (B) above, it is determined that there is a possibility that a slip-down or the like will occur due to limiting the throttle valve opening, and the requested throttle opening S1 is determined as the throttle valve opening S as it is (S200), and one routine of this flow is completed.

  On the other hand, if it is determined in S140 that the input switch 50 is off, the process of S200 is executed and the low speed restriction control is not performed.

  On the other hand, when it is determined in S120 that the current vehicle speed V exceeds the speed V1, it is determined whether or not the current vehicle speed V is equal to or less than the speed V2 (S210). The speed V2 is set to a speed of about 10 [km / h], for example, in order to control the speed V1 with hysteresis. That is, when the vehicle speed V changes in the vicinity of the speed V1, it is avoided that the determination frequently changes and the throttle valve opening becomes unstable.

  If the current vehicle speed V is equal to or lower than the speed V2, it is determined whether the throttle limit flag is on or off (S220).

  When the throttle limit flag is on, for example, it is determined that the vehicle speed V has exceeded V1 after transitioning at speed V1 or less, but has not yet reached speed V2, and the speed limit at S140 or less is determined. It is determined whether or not to perform control.

  When the throttle limit flag is off, for example, it is determined that the vehicle speed V has exceeded the speed V2 and has become the speed V2 or less but has not yet reached the speed V1 or less. Time limit control is not performed. That is, the process of determining the required throttle opening S1 as it is to the throttle valve opening S is executed, and one routine of this flow is ended (S200).

  If it is determined in S210 that the current vehicle speed V exceeds the speed V2, the throttle limit flag is set to OFF (S230), and the process of determining the required throttle opening S1 as the throttle valve opening S is executed. (S200), one routine of this flow is terminated.

  As described above, in the vehicle control apparatus 10 according to the embodiment of the present invention, basically, the low-speed limit control is performed to suppress the output of the driving force unexpected by the driver, but the predetermined angle If the shift position is a forward drive position that is greater than θ and the shift position is a downward slope greater than a predetermined angle θ and the shift position is a reverse drive position, the low speed limit control is performed. Since this is not performed, the vehicle can be prevented from sliding down in the downward direction of the road surface.

  As mentioned above, although the best mode for carrying out the present invention has been described using one embodiment, the present invention is not limited to such one embodiment, and within the scope not departing from the gist of the present invention, Various modifications and substitutions can be made to the above-described embodiment.

  For example, the aspect of detecting the road surface gradient is not limited to that of the embodiment, and a gradient sensor that directly detects the gradient may be provided.

  Further, the speed is low when the uphill is equal to or greater than the predetermined gradient θ and the shift position is a forward position, and when the shift position is the downward slope greater than the predetermined gradient θ and the shift position is the reverse position. Although the time limit control is not performed, it is possible to determine that the low speed limit control is not performed when the uphill and the downhill are not determined and the gradient is equal to or greater than the predetermined gradient θ.

  Further, the input switch 50 may not be provided, and the low-speed limit control based on the gradient may be always limited, or control without providing hysteresis may be performed in the determination of the low-speed limit control.

  The present invention can be used for a vehicle control device that limits the throttle valve opening based on at least the vehicle speed. The appearance, weight, size, running performance, etc. of the vehicle to be mounted are not limited.

It is a figure which shows an example of the whole structure of the vehicle control apparatus 10 which concerns on one Example of this invention. It is a figure which shows an example of the throttle valve opening determination flow performed by engine ECU60. It is a figure which shows an example of the map for request | requirement throttle opening setting.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Vehicle control apparatus 20 Engine 30 Accelerator position sensor 32 Shift position sensor 34 G sensor 36 Vehicle speed sensor 36
40 Throttle valve 45 Fuel injector 50 Input switch 60 Engine ECU

Claims (6)

Vehicle speed detecting means for detecting the vehicle speed, and control means for determining the throttle valve opening based on the accelerator operation. The control means is configured to control the throttle valve when the vehicle speed detected by the vehicle speed detecting means is equal to or lower than a predetermined vehicle speed. A vehicle control device that performs low-speed limit control to limit the opening degree,
Slope detecting means for detecting the slope of the road surface;
Shift position detecting means for detecting the shift position,
When the shift position detected by the shift position detecting means is a forward position and the road surface slope detected by the slope detecting means is an upward slope equal to or higher than a predetermined slope, the low speed regardless of the vehicle speed. Do not perform time limit control,
A control apparatus for a vehicle. The vehicle control device according to claim 1,
When the shift position detected by the shift position detection means is a reverse position, and the road surface gradient detected by the gradient detection means is a downward gradient greater than or equal to a predetermined gradient, the low speed is set regardless of the vehicle speed. Do not perform time limit control,
The vehicle control device further characterized by the above. Vehicle speed detecting means for detecting the vehicle speed, and control means for determining the throttle valve opening based on the accelerator operation. The control means is configured to control the throttle valve when the vehicle speed detected by the vehicle speed detecting means is equal to or lower than a predetermined vehicle speed. A vehicle control device that performs low-speed limit control to limit the opening degree,
Comprising a slope detection means for detecting the slope of the road surface;
The control means does not perform the low speed restriction control regardless of the vehicle speed when the road surface gradient detected by the gradient detection means is equal to or greater than a predetermined gradient.
A control apparatus for a vehicle. The vehicle control means according to any one of claims 1 to 3,
The control means is means for providing a hysteresis at the predetermined vehicle speed and performing the low speed control.
Vehicle control means. The vehicle control device according to any one of claims 1 to 4,
Comprising an input means capable of inputting a stop of the low speed control and a return from the stop by an operation of an operator;
Vehicle control device. The vehicle control device according to claim 5,
When the ignition is turned off while the low speed control is stopped by an operation to the input means, the low speed control is returned from the stopped state.
A control apparatus for a vehicle.

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