JPS6158332B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a neutral travel control device that saves fuel consumption by utilizing neutral travel during coasting such as when an automobile is decelerating.

[Conventional technology]

Conventionally, when a car is driving and has to temporarily stop at an intersection in front of it, it first decelerates by releasing the accelerator pedal and applying engine braking, and then applies the brakes to accelerate the deceleration. Depress the pedal to apply braking force to the wheels,
Normally, the vehicle is temporarily stopped.

[Problem that the invention seeks to solve]

However, when the engine brake is decelerated by releasing the accelerator pedal, the engine operates at a slightly lower rotational speed than the rotational speed corresponding to the vehicle speed, so excess fuel is consumed until the vehicle speed becomes considerably low.

In recent years, more and more traffic signals have been installed, and as a result, the number of opportunities for temporary stops has increased, so the above-mentioned extra fuel consumption also becomes a large proportion.

On the other hand, in order to save fuel consumption as mentioned above, some drivers may manually switch to neutral driving at their own discretion, but in that case, the vehicle will remain in neutral mode until the vehicle comes to a stop or when re-accelerating. Until the accelerator pedal is pressed, a simple operation is performed that leaves the vehicle in neutral, and other than re-acceleration, it is necessary to release the neutral or switch to neutral again at a detailed and appropriate timing. There is a problem that there is no neutral driving control.

The present invention has been made in view of the above-mentioned problems, and aims to save fuel by reliably utilizing neutral driving when a car is decelerating while driving or coasting such as when driving down a gentle slope, and also to save fuel when driving on a curved road. The purpose is to automatically cancel neutral driving to ensure stable driving on curved roads.

[Means for solving problems]

To this end, the present invention includes coasting detection means that generates a condition detection signal when a coasting condition of the automobile is detected;
A control means that generates a neutral command signal in response to a condition detection signal from the coasting detection means is connected to a transmission mechanism whose shift position is switched and selected when the automobile is running, and is connected to a transmission mechanism that switches and selects a shift position when the automobile is running. A driving means for responsively controlling the transmission mechanism to a neutral state, a curved road detecting means for detecting rotation of the steering wheel of the automobile in the left and right directions and generating a curved road detection signal, and this curved road detecting means. The vehicle is configured to include a release means for stopping the generation of a neutral command signal from the control means and reversing the drive means to release the neutral state of the transmission mechanism when it is determined that the vehicle is running on a curved road based on a curve detection signal. .

〔Example〕

An embodiment of the present invention shown in the drawings will be described below. Figure 1 shows the overall configuration of the system, which is applied to an automobile equipped with an automatic transmission control system. I am using it.

In FIG. 1, numeral 1 is a vehicle speed sensor that generates a vehicle speed signal corresponding to the traveling speed of the automobile. A throttle opening sensor 2 generates an opening signal corresponding to the opening of the throttle valve of the automobile engine. 3 is a shift control circuit which receives the vehicle speed signal and the throttle valve opening signal and determines an appropriate shift position according to the engine load;
It generates the command signal. Reference numeral 4 denotes a three-speed transmission mechanism, and when the first shift signal from the shift control circuit 3 is applied to the first switching valve 5, the hydraulic path is switched and the first gear shift position is established, which is suitable for starting the vehicle. Furthermore, when the second shift signal is applied from the shift control circuit 3 to the second switching valve 6, the hydraulic path is switched and the second shift position is established, which is suitable for acceleration. second switching valve 5,
6, the hydraulic path is switched to set the 3rd gear shift position suitable for stable driving. 7 is a neutral N valve, which is provided at the starting point of the hydraulic path of the transmission mechanism 4; when a drive signal is applied, the hydraulic path is closed, the transmission mechanism 4 is forcibly switched to a neutral state, and the drive signal disappears. This opens the hydraulic path and returns to speed change control based on the operation of the first and second switching valves 5 and 6.

The automatic shift control system including the vehicle speed sensor 1, throttle opening sensor 2, shift control circuit 3, shift mechanism 4, first switching valve 5, and second switching valve 6 has the same configuration as the known system. , a detailed explanation thereof will be omitted.

8 is an accelerator pedal of a car, which is pressed by the driver to adjust the driving speed. Reference numeral 9 denotes an accelerator sensor serving as coasting detection means, which is a switch that closes in conjunction with the depression of the accelerator pedal 8 and generates an operation signal.When the depression is released, the switch opens and detects the coasting condition. ing. Reference numeral 10 denotes a steering sensor serving as a curve detection means, which generates a curve detection signal when the steering wheel rotates to the left or right. Reference numeral 11 denotes a neutral (N) switch, which is manually operated by the driver to issue a switch signal instructing a neutral state. Reference numeral 12 denotes a starting switch that is turned on when starting the automobile.When turned on, the engine is started, and when the switch is turned on, a starting signal is generated. Reference numeral 13 denotes a release switch, which is turned on manually by the driver to generate a release signal when the driver wants to release the neutral travel control function.

14 is a single-chip microcomputer that executes digital arithmetic processing according to a control program including a predetermined neutral control program, and includes a several megahertz (MHz) crystal oscillator 15.
A stabilizing power supply circuit (not shown) that starts operating when the engine key switch is connected and the engine key switch is turned on.
It enters the operating state by receiving a stabilized voltage of 5V from Driving control includes an operation signal from the accelerator sensor 9, a prohibition signal from the steering sensor 10, a switch signal from the N switch 11, a start signal from the start switch 12, and a release switch 1.
Upon receiving the release signal from 3, when both the operation signal and prohibition signal disappear, a neutral (N) command signal is generated, and when either signal is generated, an N reset signal is generated, and the start signal or generates the same signal depending on the presence or absence of the switch signal,
The cancellation signal partially bypasses the calculation processing of the neutral control. This microcomputer 14 has a read-only memory (ROM) that stores various control programs including a neutral control program that defines calculation procedures for neutral travel control, and sequentially reads control programs from this ROM. The central processing unit (Central processing unit) executes the calculation processing corresponding to the procedure.
Processing Unit (CPU)) and memory (Random Access Memory (RAM)) that temporarily stores various data related to the arithmetic processing of this CPU and allows the CPU to read the data when necessary.
The main components include a clock generator that generates reference clock pulses for the various calculations described above using a crystal oscillator 15, and an input/output (I/O) circuit that adjusts the input and output of various signals to and from the outside. of semiconductors
It is made of LSI (Large Scale Integration) circuit. Reference numeral 16 denotes a drive circuit that latches the N command signal from the microcomputer 14 to operate the N valve 7. The latch signal is reset by the N reset signal from the microcomputer 4, and the N valve 7 is operated by latching the N command signal from the microcomputer 4. When the N-valve 7 is activated, the transmission mechanism 4 is controlled to a neutral state, and upon reset, the N-valve 7 is turned off to release the neutral state and return to the shift position under automatic shift control.

The microcomputer 14 constitutes a control means, and the drive circuit 16 and the N valve 7 constitute a drive means.

Next, the operation of the above configuration will be explained with reference to the calculation flowcharts of FIGS. 2 and 3.

2 is a calculation flowchart showing the overall calculation processing of the microcomputer 14 according to the control program, and FIG. 3 is a calculation flowchart showing the detailed calculation processing of the neutral control routine forming the neutral control program in FIG.

First, in a car equipped with this device, when the key switch is turned on to start driving, the microcomputer 14 starts operating by supplying a stabilized voltage from the stabilized power supply circuit. As a result, the arithmetic processing is started from the start step 100 in FIG. 2, and the process proceeds to the initial setting routine 200, where the registers, counters, latches, etc. in the microcomputer 14 are set to the initial states necessary for starting the arithmetic processing, and the neutral control routine 300
Proceed to.

In this neutral control routine 300, the accelerator sensor 9, steering sensor 10, N switch 11, start switch 12, release switch 13
Based on the respective signals, the on/off operation of the N valve 7 is controlled to perform arithmetic processing for setting and resetting the neutral state, and then the program proceeds to the next various system control routines 400.

This various system control routine 400 executes arithmetic processing for controlling various in-vehicle systems, and then returns to the neutral control routine 300.
Descriptions of the various sensors and their respective drive units related to the arithmetic processing of the various system control routines 400 will be omitted.

Then, the arithmetic processing from the neutral control routine 300 to the various system control routines 400 is repeated to control neutral driving. At this time, in the neutral control routine 300, from the start judgment step 301, the N switch judgment step 302, the release judgment step 303, the accelerator operation judgment step 304, the curve judgment step 306 are reached, and the N command step 307 is reached. A command signal is applied to the S terminal of the drive circuit 16. Therefore, this drive circuit 16 latches the signal, closes the N valve 7, and forcibly controls the transmission mechanism 4 to a neutral state. Each of the above steps 301 and 30 is continued until the various detection states change.
The arithmetic processing through steps 2, 303, 304, 306, and 307 is repeated.

Subsequently, after operating the automatic transmission control system to the neutral range, the start switch 12 is turned on to start the engine, the starter rotates, and a start signal is applied to the microcomputer 14. Therefore, when the start judgment step 301 of FIG. In addition to the circuit 16, the N valve 7 is kept closed to maintain the transmission mechanism 4 in the neutral state, and in addition to the starter energization control by the safety switch linked to the neutral range of the automatic transmission control system, the engine has double safety. Ensure starting. Then, when the starting is completed, the starting signal from the starting switch 12 disappears, so the neutral control routine 300
The calculation is performed when the judgment in the start-up judgment step 301 in FIG.
6. Return to the arithmetic processing through the N command step 307 and maintain the neutral state.

Subsequently, when the automatic transmission control system is operated to the drive range and the accelerator pedal 8 is depressed for starting, an operation signal is generated from the accelerator sensor 9, so that the accelerator operation determination step 30 in FIG. 3 is performed.
4, the judgment is reversed from NO to YES, and the process does not proceed to the curve judgment step 306, but proceeds to the N reset step 305, where the N reset signal is applied to the R terminal of the drive circuit 16. Therefore, in order to reset the drive circuit 16 and turn off the N valve 7,
The hydraulic path of the transmission mechanism 4 is opened, and the automatic transmission control device controls the transmission position. As a result, at the time of starting, the first switching valve 5 is activated and the transmission mechanism 4 is controlled to the 1st speed position, thereby performing an appropriate starting. after that,
As the traveling speed increases, the vehicle switches from the second gear position to the third gear position, and shifts to stable running.

At this time, while the accelerator pedal 8 is being depressed and the operation signal continues to be generated from the accelerator sensor 9, the microcomputer 14 performs the startup determination step 301 and the N switch determination step 30 in the neutral control routine 300.
2. The arithmetic processing through the release determination step 303, accelerator operation determination step 304, and N reset step 305 is executed, and the N reset signal is applied to the drive circuit 16 to maintain the N valve 7 in the OFF state.

Next, when the accelerator pedal 8 is released during deceleration, if the steering wheel is not turned on a curved road, the operation signal from the accelerator sensor 9 disappears, and the steering sensor 10 detects a curved road. Since no detection signal has been generated, the determination in the accelerator operation determination step 304 is reversed from YES to NO in the neutral control routine 300, and the process proceeds to the curve determination step 306, where the determination is made.
When the result is NO, the arithmetic processing proceeds to N command step 307, and the N command signal is applied to the drive circuit 16.
The N valve 7 is operated to forcibly switch the transmission mechanism 4 to a neutral state. Thereafter, while the accelerator is released, the same calculation process is repeated to maintain the neutral state, and the engine rotation is maintained at a low speed regardless of the current traveling speed to save fuel consumption. Therefore, when the vehicle temporarily stops at an intersection or the like, it is possible to save fuel consumption from the start of deceleration until the vehicle stops, and the more frequently the vehicle stops temporarily, the greater the saving effect becomes.

Furthermore, even when the accelerator pedal 8 is released on a downhill slope, it is possible to control the vehicle to a neutral state in the same way as described above, thereby saving fuel consumption.

On the other hand, since the steering sensor 10 generates a curve detection signal when driving on a curve where switching control to neutral is not suitable, the determination is made when the curve determination step 306 is reached in the neutral control routine 300 when the accelerator is released.
YES and does not proceed to N command step 307.
Proceeding to N reset step 305, the N reset signal is applied to the drive circuit 16. Therefore, the N valve 7 is turned off and the vehicle does not enter the neutral state, maintaining the shift position by automatic shift control, so that stable traveling on curved roads can be achieved.

In addition, in order for the driver to forcefully switch to the neutral state by manual operation, the N switch 11 is activated.
When the N switch 11 is turned on, a switch signal is applied to the microcomputer 14. Therefore, when the N switch determination step 302 is reached from the startup determination step 301 in the neutral control routine 300 of the microcomputer 14, the determination is reversed from NO to YES.
The process does not proceed to the release determination step 303, but proceeds to the N command step 307, where the N command signal is applied to the drive circuit 16, the N valve 7 is operated, and the first and second switching valves 5, 6 are activated.
, and the transmission mechanism 4 is forcibly switched to a neutral state. Furthermore, when the N switch 11 is released, the switch signal disappears, so
When the N switch determination step 302 is reached, the determination is reversed from YES to NO, and the process returns to the normal arithmetic processing which proceeds to the release determination step 303.

Additionally, when the driver turns on the release switch 13 to release the neutral driving control function,
A release signal is applied to the microcomputer 14 from the release switch 13. Therefore, in the neutral control routine 300, the cancellation determination step 3
03, the determination is reversed from NO to YES, and the operation is repeated to proceed directly to N reset step 305 without proceeding to accelerator operation determination step 304, bypassing the calculations at each step 306 and 307 after accelerator operation determination step 304. to stop the neutral travel control function.

In the above-described embodiment, the automatic shift control is performed by the shift control circuit 3, but the automatic shift control may be centrally controlled by the microcomputer 14 together with the neutral travel control.

Further, although the embodiment has been shown to be applied to an automobile equipped with an automatic transmission control device, it may also be applied to a manual transmission type automobile, in which case a switching actuator that automatically switches to a neutral state may be used.

Further, although the gear shift position is controlled in order to control the vehicle to a neutral state, neutral running may be controlled by, for example, connecting and disconnecting a clutch provided between the engine and the wheel drive shaft.

In addition, although the microcomputer 14 is shown as a control means that performs neutral running control through digital calculation processing of software, similar control may be performed using ordinary hard logic digital electronic circuits or analog electronic circuits. good.

Further, although the accelerator sensor 9 is shown as the coasting detection means, other sensors may be used, such as those that detect coasting conditions in the stress direction of the connecting portion between the engine and the wheel drive shaft.

Further, although the steering sensor 10 is shown as a curved road detection means, other detection means may be used, such as one that detects a curved road based on the rotational deviation of the left and right wheels, or one that detects the lateral G (acceleration) of the vehicle body. May be used.

〔Effect of the invention〕

As described above, in the present invention, when the vehicle is decelerating or coasting, such as when traveling downhill, it is possible to automatically utilize neutral running to maintain the engine rotation at a low speed, thereby saving fuel. Furthermore, when traveling on a curved road, the switching to neutral mode can be stopped to ensure stable travel on a curved road, which is an excellent effect.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention;
FIG. 2 is a calculation flowchart showing the calculation processing of the control program of the microcomputer shown in FIG. 1, and FIG. 3 is a calculation flowchart showing the detailed calculation processing of the neutral control routine shown in FIG. 4... Speed change mechanism, 7, 16... N valve and drive circuit forming drive means, 9... Accelerator sensor forming coasting detection means, 10... Steering sensor forming curve detection means, 14... Control means Eggplant microcomputer.

Claims (1)

[Scope of Claims] 1. Coasting detection means for generating a condition detection signal when detecting a coasting condition of the automobile; control means for generating a neutral command signal in response to the condition detection signal from the coasting detection means; a driving means connected to a transmission mechanism for selecting a transmission position and controlling the transmission mechanism to a neutral state in response to a neutral command signal from the control means; a curved road detection means that detects rotation and generates a curved road detection signal; and when it is determined that traveling on a curved road is determined based on the curved road detection signal from the curved road detection means, generation of a neutral command signal from the control means is stopped; A neutral travel control device comprising: a release means for reversing the drive means to release the neutral state of the transmission mechanism.