JPH05231194A - Stepping reaction force controller for accelerator pedal - Google Patents

Abstract

PURPOSE:To provide the driving feeling conforming to a driver's demand or the operation feeling conforming to the road surface state, operation state, etc., to a driver, by adjusting and controlling the stepping on reaction force of an accelerator pedal. CONSTITUTION:A return spring stopper 17 equipped with a projection 15 which contacts one bar part 9 of a return spring 13 for applying a stepping reaction force to an accelerator pedal 1 is turned by a stepping motor 21 on the basis of the control signal SG supplied from an electronic controller 25, and the initial return force FO acting on an accelerator pedal 1 can be varied. An electronic controller 25 calculates the road surface mu value from the sensor signal, and on a low mu road, the stepping reaction force of the accelerator pedal 1 is increased to suppress the stepping ON of the accelerator by a driver.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a reaction force on an accelerator pedal of a vehicle.

[0002]

2. Description of the Related Art Conventionally, there is a constant relationship between the accelerator pedal depression amount and the throttle opening amount, and in a public car, the throttle valve opening variation amount is usually set to a large amount with respect to the stroke change at the beginning of depression. The tendency was to increase the torque rise in the low speed range and emphasize operability from the low speed range to the middle and high speed range.

On the other hand, in a vehicle such as a European sports car where emphasis is placed on operability at high speeds, when the pedal is depressed below a predetermined level, the throttle valve opening change is small, but a considerable amount is depressed. It was set so that the throttle opening could be opened. With such a setting, it is possible to obtain a good acceleration performance by reacting sensitively to an accelerator operation during high-speed traveling without converging the torque change.

By the way, the driver usually understands how much he or she depresses the accelerator by the magnitude of the reaction force against the depression of the accelerator. Therefore, the driver usually understands from the experience that what degree of stepping reaction force can be obtained and how much acceleration can be obtained according to the habit of the vehicle owned by the driver. .. That is, the driver is driving according to his or her habit while understanding his or her operating state by the stepping reaction force.

Therefore, even in an ice burn or the like (hereinafter, referred to as a low μ road) where the friction coefficient of the road surface is small, the driver inadvertently depresses the accelerator until he obtains the stepping reaction force that he or she is normally accustomed to. There are cases. In such a case, a slip that the driver did not intend to occur and the vehicle may skid.

Conventionally, in order to prevent such a situation from occurring, a traction control system for electronically controlling the throttle opening and the braking force (Japanese Patent Laid-Open No. 60-128).
No. 055) has been proposed.

[0007]

However, there is a problem that such a system is complicated and expensive. Also,
With a traction control system that forcibly controls the throttle opening, in the unlikely event that the system fails, the throttle will continue to open or close, making it impossible to control the opening, or acting as the opposite of the required control. There was also a risk that it would end up.

On the other hand, instead of such a complicated system,
For example, Japanese Utility Model Laid-Open No. 1-127944 and Japanese Patent Laid-Open No. 2-1023.
No. 31, JP-A-2-286839, etc., a device having a structure in which an intermediate link relation is changed so that the opening degree of the throttle valve appears differently even if the accelerator pedal depression amount is the same is also proposed. There is.

If such a system for adjusting the intermediate link is adopted, it is possible to prevent the slip at the start of acceleration on the low μ road, but this time, even if the driver depresses considerably, the throttle will not be fully opened. Therefore, the driver feels uncomfortable that the output does not increase as expected even when the accelerator is fully depressed. In some cases, there is a possibility that a trouble such as a quick escape may not be avoided.

In order to realize the characteristics adopted in sports cars and the like when setting the relationship between the accelerator pedal depression amount and the throttle opening as described above, a non-linear spring or a complicated link mechanism is provided. It is necessary to devise such as
There was also a problem that free design could not be easily done.

Therefore, it becomes possible to control the output of the engine in accordance with the driver's preference, road surface condition, driving condition, etc., and even under such control, the driver does not feel uncomfortable such as poor acceleration, if necessary. It is possible to operate until the throttle is fully opened,
In addition, the present invention has been completed for the purpose of enabling a free and simple design in designing the relationship between the accelerator pedal depression amount and the throttle opening.

[0012]

SUMMARY OF THE INVENTION The accelerator pedal depression reaction force control device of the present invention, which has been completed to achieve the above object, provides an accelerator pedal without changing the relationship between the accelerator depression amount and the throttle opening degree. By changing the relationship between the pedaling amount and the pedaling reaction force from the accelerator, it is possible to appeal to the driver's sense and guide the driver to an appropriate accelerator operating state.

Specifically, as described in claim 1, the accelerator pedal depression reaction force control device according to the present invention is a reaction force for the accelerator pedal, and a reaction force with respect to the accelerator pedal according to the depression amount of the accelerator pedal. And a reaction force reference value setting means for setting a reference value of the reaction force applied by the reaction force application means, and a setting state of the reaction force reference value by the reaction force reference value setting means. And a reaction force reference value changing means.

According to this apparatus, the reaction force reference value changing means can change the reaction force reference value. If this reaction force reference value is changed, the reaction force received by the driver will be different even if the accelerator is depressed by the same amount. Therefore, as shown in FIG. 1, the changed state CHG1 in which the reaction force reference value is made larger than that in the normal state NOR to make it heavier as a whole
If it is switched to, the driver feels a certain stepping reaction force F1, and the stepping amount S smaller than the stepping amount ST1 in the normal state.
Since the operation is performed at T2, it becomes difficult to step on the accelerator carelessly after all. This is because the driver usually judges his / her stepping amount ST by the stepping reaction force F. As a result,
The driver will be guided to make the accelerator operation amount smaller than usual.

Further, the reaction force reference value may be changed according to the accelerator depression amount, and as shown in the upper side of FIG. 2, the accelerator depression amount ST and the depression reaction force F are convex upward. It is possible to easily set and switch to a non-linear relationship. From the normal state NOR shown to this non-linear characteristic state CH
When the driver switches to G2, the driver can step on the reaction forces Fa, Fb,
Actual strokes STa, STb, STc with respect to Fc
Instead of the normal strokes STa ', STb', S
Embrace the feeling of being Tc '. Therefore, the throttle opening THθ with respect to the accelerator depression amount (sensation depression amount) ST ′ as the driver's sense is as if the characteristic was changed to a downward convex as shown in the lower side.

As a result, although the responsiveness in the low speed range is not so good, it becomes possible to drive with a feeling that is preferred by a sports car or the like which shows a sensitive responsiveness in the high speed range. According to the accelerator pedal depression reaction force control device of the present invention described above, the relationship between the accelerator depression amount and the throttle opening is not changed, and only the depression reaction force received by the driver is changed. is there. Therefore, for example, even on a low μ road or the like, even if a large depression reaction force that makes it harder to depress the accelerator than on a normal road surface is set, it is possible to control the throttle to be fully opened by still depressing the accelerator. Therefore, if there is a need to escape to avoid danger, it can be dealt with in the same manner as in the normal operating state. In addition, since the throttle opening can be controlled from fully closed to fully open in this way, the driver does not feel uncomfortable that the output does not increase no matter how much the driver depresses.

That is, in the accelerator pedal depression reaction force control device of the present invention, the throttle valve is not essentially opened or forcedly opened, but it is difficult for the driver to inadvertently press the accelerator or the accelerator is not opened. By adopting a configuration that improves the operation feeling when you depress the pedal a lot, output control with the conventional traction control system that separates and controls the accelerator pedal and throttle valve, and the accelerator pedal and throttle valve The effect is completely different from that of the conventional device that controls the output by changing the link relationship.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings. As shown in FIG. 3, the apparatus of the embodiment includes an accelerator pedal 1 that rotates in response to a driver's depression, an accelerator wire 3 that transmits the movement of the accelerator pedal 1 to a throttle valve (not shown), and an accelerator depression. An accelerator position sensor 5 for detecting the position AP and bar portions 7 and 9 bent at both ends are provided, and one of the bar portions 7 is brought into contact with the upper bar 11 of the accelerator pedal 1 from the front side in the figure. A return spring stopper 1 including a return spring 13 and a protrusion 15 that comes into contact with the other bar portion 9 of the return spring 13 from the front in the figure.
7 and. This return spring stopper 1
Reference numeral 7 is connected to a rotor shaft 23 of the stepping motor 21. Then, the control signal S from the electronic control unit 25
When the stepping motor 21 changes the operating position based on G, the initial return force F acting on the accelerator pedal 1
You can change 0.

Here, the initial return force F0 is a relationship between the amount x0 of initial deformation (deformation in a state where the accelerator pedal 1 is not depressed) applied to the return spring 13 and the spring constant K of the return spring 13. Can be expressed as

[0020]

[Equation 1]

Further, the depression reaction force F felt when the driver depresses the accelerator pedal 1 is expressed by the following equation, where x1 is the deformation amount of the return spring 13 according to the depression of the driver.

[0022]

[Equation 2]

Therefore, if the initial return force F0 is set to be relatively large, the driver will feel as if he / she depresses the accelerator to some extent even if the accelerator is actually slightly depressed. On the contrary, if the initial return force F0 is set to be relatively small, the driver will feel as if the accelerator is slightly depressed even if the driver strongly depresses the accelerator.

The driver cannot directly understand the accelerator depression amount, and based on the depression reaction force when the accelerator is operated,
It is normal to understand how much you are currently stepping on as a sense. Therefore, as shown in FIG. 4, when the turning position of the return spring stopper 17 is changed so that the initial return force F0 becomes larger than that in the normal state (FIG. 3), the driver always has a smaller depression amount. At times, the same pedal reaction force as when the vehicle is normally depressed to some extent is felt, and it becomes difficult to inadvertently depress the accelerator pedal 1. Even if the initial return force F0 is changed as described above, the relationship between the depression amount of the accelerator pedal 1 and the throttle valve opening is not changed, and as a result, the driver operates the accelerator pedal 1 with a normal feeling. Even if you step on it, you will not get much output. Therefore, the driver is unconsciously guided to the driving operation state in which the output is suppressed. Further, if such a change in the initial return force is executed when the driver has already stepped on the accelerator pedal 1 by a considerable amount, the driver feels that he / she has stepped on too much and guides the driver to unconsciously return the accelerator pedal 1. To be done.

On the contrary, as shown in FIG. 3, if the turning position of the return spring stopper 17 is changed so that the initial return force F0 becomes smaller than that in the normal state (FIG. 1), the driver is more than usual. You will feel a stepping reaction force that is as large as when you operate it normally only after you depress it widely. Therefore, if such changes are made, the driver may be unconsciously guided in a direction in which he / she depresses the accelerator pedal deeper than usual, resulting in the impression that the acceleration is better than usual. become.

3 to 5, reference numeral 27 is a counter weight for returning the accelerator pedal 1, and reference numerals 28 and 29 are projections and stoppers for preventing the return spring 13 from being loosened too much. Next, the case where the change control of the initial return force in this embodiment is performed will be described, and the action and effect in that case will also be described.

Before entering specific control contents, the configuration of the control system will be described. The control system of the embodiment includes a CPU 25a and a ROM
25b, an electronic control unit 25 provided with a RAM 25c, and its I / O port 25d has a detection signal AP from the above-mentioned accelerator position sensor 5, an automatic transmission 31, a pressure sensor 33, and a rotation speed sensor. The gear shift position signal AT, the intake pipe negative pressure PM, the engine speed NE, and the drive wheel speed Vd are input from the drive wheel speed sensor 35 and the drive wheel speed sensor 37. Then, a predetermined calculation is executed on the basis of these various input signals, and the control signal SG obtained as a result is sent to the above-mentioned stepping motor 21 via the drive circuit 25e.
Given to.

In the embodiment, the control shown in FIG. 6 is executed at every predetermined interrupt timing. In this control,
First, various sensor signals such as the accelerator position AP, the shift position AT, the intake pipe negative pressure PM, the engine speed NE, and the drive wheel speed Vd are input (S1), and the engine torque map (intake pipe negative pressure) set in the ROM 25b is input. The drive torque T is estimated using a map in which the relationship between the pressure PM and the drive torque T is set for each engine speed NE) (S2), and the shift position is determined based on the speed reduction ratio determined from the shift position signal AT. A correction is added (S3), the drive wheel acceleration ACCd is calculated from the difference between the value input this time and the value input last time for the drive wheel speed Vd (S4), and the drive torque obtained by previously estimating / correcting is calculated. The friction coefficient μ of the road surface is calculated from the relationship between T and the driving wheel acceleration ACCd (S5). If the drive torque is the same, it can be said that the road surface is more likely to slip as the drive wheel acceleration ACCd is larger, and the friction coefficient μ of the road surface can be calculated by investigating and setting this relationship in advance. For the arithmetic processing up to this point, for example, the technique introduced in detail in Japanese Patent Laid-Open No. 19622/1990 can be applied as it is.

When the road surface friction coefficient μ is calculated in this way,
Based on the value, it is determined whether or not the road surface on which the vehicle is currently traveling is a predetermined low μ road (S6). Here, if it is determined that the road is a predetermined low μ road, an initial return force characteristic map (hereinafter referred to as F0 map) during traveling on the low μ road set in the ROM 25b is input. The accelerator position AP is referred to (S7). This F0 map is a map that defines the relationship between the accelerator position AP and the initial return force F0. In particular, at the beginning of the depression of the accelerator pedal 1, the driver is made to feel a larger reaction force on the asphalt than on the asphalt road surface. It is stored in advance in the ROM 25b as a map in which various nonlinear characteristics are set.

Then, based on this reference result, the control step number SG of the stepping motor 21 is determined (S
8), according to the determined value SG, the stepping motor 21
Is controlled to control the initial return force F0 (S9). On the other hand, in the determination processing of S6, if it is determined that the road surface on which the vehicle is currently traveling is not a predetermined low μ road, the initial return force set for traveling on the asphalt road (regardless of the accelerator position AP is constant. The normal control step number SGnor is selected based on the value) (S10), and the stepping motor 21 is drive-controlled according to the control value SGnor (S9).

As a result of the above control, the relationship between the stepping amount ST and the stepping reaction force F is set to the normal state NOR of linear relationship as shown in FIG. Compared to normal state NOR, a large reaction force is generated for the same accelerator depression amount, especially, even at the beginning of accelerator depression when starting, even if the depression amount is slightly increased, the depression reaction force F increases sharply. Is set to increase.

As a result, the driver can depress the accelerator shallower than usual and only slowly, and the driver is naturally guided to a driving state in which the output is suppressed. In this way, it is possible to suppress excessive depression of the accelerator pedal and prevent slipping or the like at the time of starting on an icy road. Also,
From a certain point in time, the relationship is almost parallel to the normal state NOR, so when starting the vehicle, the output will slowly increase to prevent slippage, but if you start to some extent, you will get a feeling of acceleration similar to normal. Is becoming And low μ
Since the road has a larger stepping reaction force as a whole, it is difficult for the driver to operate the throttle fully. In addition, when driving from a normal asphalt road surface to a road surface painted with water, the reaction force of the pedal increases as the road surface changes, so the driver may not step on the accelerator too much. You will feel like, and will naturally return the accelerator.

However, since the relationship between the throttle opening and the actual depression amount of the accelerator pedal is not changed, it is possible to fully open the throttle valve up to the maximum output if necessary. As a result, according to the present embodiment, the driver
When traveling on a low μ road, naturally, as a result, it is more difficult to depress the accelerator than usual, and it is possible to prevent slips from occurring.

Moreover, in the present embodiment, the relationship between the accelerator opening amount and the throttle opening degree is not changed as in the prior art, and the accelerator pedal is prohibited from being depressed to the deepest position simply by making it difficult to depress. Since it is not a thing, the throttle can be fully opened if necessary. Also, in the unlikely event that the system fails, the throttle opening degree can be controlled according to the actual depression amount of the accelerator pedal simply by making the depression reaction force abnormal, which may result in operation failure. Absent.

Further, in this embodiment, the lower protrusion 28 and the rear stopper 29 of the return spring stopper 17 are provided.
Even if a failure occurs in the system, the accelerator pedal 1 does not become too light, and the driver is prevented from depressing the accelerator pedal too much.

Next, various application examples to which this basic system is applied will be described. In the first application example, as shown in FIG. 8, the shift position signal AT from the automatic transmission 31 is input (S11), and the control value SG of the stepping motor 21 that is preset according to the shift range is selected. (S12), the stepping motor 21 is driven based on the control value SG to control the initial return force F0 (S13). The control value SG set here is set so as to generate an initial return force larger than usual in the R range, and the L range, 2
The speed range and the 3rd speed range are set to generate an initial return force smaller than usual. Therefore, the relationship between the accelerator depression amount ST and the depression reaction force F is changed as shown in FIG. 9, and in the R range, the relation that the accelerator is not accidentally depressed, on the contrary, in the L range and the like, the acceleration is improved. Therefore, the operation of stepping on the accelerator with a relatively large size is performed smoothly. As a result, the driver
The operator is unknowingly guided to the optimum accelerator pedal operating state according to the gear position.

As shown in FIG. 10A, the second application example is provided with a driving mode switch 41 operated according to the driver's preference, and an economy mode in which fuel economy is emphasized and a sports mode in which acceleration is emphasized. This is for a system that can be changed with and. That is, in this second application example, the stepping motor 21 is controlled so as to have a large initial return force F0ec in the economy mode, and the stepping motor 21 is controlled so as to have a small initial return force F0sp in the sports mode. As a result, the relationship between the accelerator depression amount ST and the depression reaction force F becomes as shown in FIG. 10 (B), and the driver is naturally guided to the accelerator operation state suitable for economy traveling and sports traveling.

As shown in FIG. 11, the third application example is an example in which a volume switch 43 for adjusting the initial return force is provided to enable adjustment according to the driver's preference. It can be said that it is an advanced version of the above-mentioned second application example, and it is possible to make fine adjustments according to the driver's preference.

In the fourth application example, as shown in FIG. 12, the stepping motor 21 is driven according to the steering angle signal from the steering angle sensor 45 so that the initial return force F0 increases as the steering angle increases. This is an example of controlling. According to this example, as shown in FIG. 13, when steering is performed while driving with the accelerator pedal depressed to a certain stepping amount STx, the pedaling reaction force F is increased accordingly (see the figure). Since it is changed to the one-dot chain line), when the steering is started, the driver unintentionally releases the accelerator pedal, and thereafter does not depress too much.

The fifth application example is, as shown in FIG. 14, an example in which in a turbo-equipped vehicle, the stepping reaction force is increased in the region where the turbo switch is turned on. That is, in a high rotation range where the turbo switch operates (a region where the accelerator depression amount is large), by making the pedaling reaction force F larger than in a region below that, the driver depresses the accelerator pedal too much. Therefore, it is possible to prevent the output from becoming excessive by overlapping the turbo operation and the accelerator operation. The switching may be simply performed only by the accelerator depression amount, or the turbo region may be determined in relation to the intake pipe negative pressure PM and the like.

The sixth application example is, as shown in FIG. 15, an example of finely switching according to the road surface condition. In recognizing the road surface state, it can be based on the calculation of the road surface friction coefficient μ based on the driving wheel acceleration as described above, or by detecting the road surface state using an ultrasonic sensor or an optical sensor,
A humidity sensor, a temperature sensor, or the like may be used to automatically determine whether the weather condition is detected, or the driver's operation switch may be used for setting.

Although the embodiments and various application examples of the present invention have been described above, the present invention is not limited to the configurations of the embodiments and application examples, and can be implemented in various modes without departing from the scope of the invention.
For example, the present invention may be applied to adjust the torque characteristics (sensation) of each vehicle instead of switching between the normal state and the driving state. That is, as shown in FIG. 16, with vehicles A, B, and C having exactly the same hardware configuration, a certain vehicle A has an upwardly convex characteristic as a normal state only by changing the conditions that determine the relationship between the accelerator position and the initial return force. With another vehicle B, a linear function characteristic can be given, and with another vehicle C, a downward convex characteristic can be given. Such adjustment of various characteristics has conventionally required changing the characteristics of the return spring for each vehicle and adjusting the link relationship between the accelerator pedal and the throttle valve. As a result, the remarkable effect that a free design in the same vehicle type can be realized extremely easily is obtained.

Further, not only the reaction force applying means using the coil spring but also the spiral spring or the leaf spring may be used to adjust the initial displacement amount. The present invention can also be realized by switching the orifice diameter of the dashpot by applying a stepping reaction force by the dashpot. In addition, the clutch plate or the like may be pressed against the accelerator rotation shaft to apply the reaction force by the frictional force, and the pressing force to the clutch plate may be adjusted.

[0044]

As described above in detail, according to the accelerator pedal depression reaction force control device of the present invention, it is possible to perform output control in accordance with the driver's preference, road surface condition, driving condition, and the like. Even under control, the driver can operate up to full throttle if necessary without feeling uncomfortable such as poor acceleration.
In addition, when designing the relationship between the accelerator pedal depression amount and the throttle opening degree, it is possible to enable a free and simple design.

[Brief description of drawings]

FIG. 1 is an explanatory view showing the operation of the device of the present invention.

FIG. 2 is an explanatory diagram showing the operation of the device of the present invention.

FIG. 3 is a configuration diagram of a system as an example.

FIG. 4 is an explanatory diagram of an operation for reducing the initial return force in the embodiment.

FIG. 5 is an explanatory diagram of an operation for increasing the initial return force in the embodiment.

FIG. 6 is a flowchart of stepping reaction force control in the embodiment.

FIG. 7 is an explanatory diagram showing the operation of the embodiment.

FIG. 8 is a flowchart of a stepping reaction force control of the first application example.

FIG. 9 is an explanatory diagram showing an operation according to the first application example.

FIG. 10 is an explanatory diagram of a second application example.

FIG. 11 is an explanatory diagram of a third application example.

FIG. 12 is an explanatory diagram of a fourth application example.

FIG. 13 is an explanatory diagram showing an operation according to a fourth application example.

FIG. 14 is an explanatory diagram of a fifth application example.

FIG. 15 is an explanatory diagram of a sixth application example.

FIG. 16 is an explanatory diagram of another application example.

[Explanation of symbols]

1 ... accelerator pedal, 3 ... accelerator wire,
5 ... Accelerator position sensor, 13 ... Return spring, 17 ... Return spring stopper, 21 ... Stepping motor, 25 ... Electronic control device, 31 ... Automatic transmission, 33 ... Pressure sensor, 35 ... Rotation speed sensor, 37 ... Driving wheel speed sensor, 41 ... Travel mode switch, 43 ... Volume switch, 45 ... Steering angle sensor.

Claims (1)

[Claims] 1. An accelerator pedal, a reaction force applying means for applying a reaction force to the accelerator pedal according to a depression amount of the accelerator pedal, and a reference value of a reaction force applied by the reaction force applying means. An accelerator pedal depression reaction force control device comprising reaction force reference value setting means and reaction force reference value changing means for changing the setting state of the reaction force reference value by the reaction force reference value setting means.