JPH049691B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a vehicle speed overspeed warning device during autocruise, and is used to prevent the speed of a vehicle during autocruise from increasing excessively and causing a dangerous situation. It has been devised to make it possible.

<Prior art> When an electronic governor is used in the fuel injection system of a vehicle powered by a diesel engine, such as a truck, in addition to normal manual driving by the driver's manual transmission operation and accelerator pedal operation, By commanding the electronic governor to set the target vehicle speed, auto-cruise, which allows the vehicle to drive at a constant speed without operating the accelerator pedal, becomes possible.

Generally, electronic governors have a control section equipped with a microcomputer, and the function of this control section is to set the position of the control rack in the fuel injection system, so that the fuel is in an optimal state under the given conditions. Adjust the injection amount. Fig. 3 shows an example of a schematic configuration of the control rack and its surroundings, and Fig. 4 shows an example of the electrical circuit of an electronic governor equipped with an auto-cruise function. In Fig. 3, 1 is a fuel injection pump, and 2 is a control The control rack 2 is a component of the fuel increase/decrease mechanism in the pump 1, and the injection amount of the pump 1 changes depending on the position of movement in the horizontal direction in the drawing. Reference numeral 3 denotes a rack position setting section (hereinafter referred to as an actuator), which is composed of a linear solenoid 4 and a plunger 5, and the plunger 5 is connected to the rack 2 described above. A rack position sensor 7 is also connected to the rack 2 via a link 6. 8 is a pump camshaft, and 9 is its rotation speed sensor.

On the other hand, in FIG. 4, 10 is a control unit of the electronic governor, which includes a CPU (central processing unit such as a microcomputer) 11, and a ROM (read-only memory).
12, RAM (Random Access Memory) 13,
Pulse waveform shaping circuit 14, buffer circuit 15, multiplexer 16, A/D (analog/digital)
It consists of a converter 17, a D/A (digital/analog) converter 18, and the like. Then, the output of the engine speed sensor 21 and the output of the vehicle speed sensor 22 are pulse-shaped by a pulse waveform shaping circuit 14 and then sent to the CPU.
11. The output of the auto cruise setting device 20, the output of the brake switch 23, and the output of the clutch switch 24 are amplified by a buffer circuit 15 and supplied to the CPU 11. Fuel temperature sensor 2
5, the output of the intake pressure sensor 26, the output of the intake air temperature sensor 27, and the accelerator pedal position sensor 2.
The output of 9 is supplied to the CPU 11 via a multiplexer 16 and an A/D converter 17. In the case of normal manual driving in which auto cruise is not set, the CPU 11 determines the optimal fuel injection amount, that is, the optimal easy position, according to the output signal of the accelerator pedal position sensor 29, various sensor signals, and switch signals. The rack position setting signal is sent to the actuator drive circuit 3 through the D/A converter 18.
Output to 0. In addition, when auto cruise is set, the CPU 11 determines the optimal fuel injection amount ( The rack position setting signal is output to the actuator drive circuit 30 through the D/A converter 18. Note that the transmission is manually shifted. The actuator drive circuit 30 drives the above-mentioned actuator 3 in response to the rack position setting signal thus applied. At this time, the actuator drive circuit 30, the actuator 3, and the rack position sensor 7 constitute a servo control system.

<Problems to be solved by the invention> However, with the above-mentioned auto cruise function, when the vehicle approaches a downhill slope, the actual speed of the vehicle immediately increases compared to the vehicle speed set for auto cruise. There have been cases where the driver has come closer to a vehicle than expected, resulting in a dangerous situation.

SUMMARY OF THE INVENTION In view of the problems of the prior art described above, an object of the present invention is to provide a vehicle speed overspeed warning device for autocruise that issues a warning when the vehicle speed exceeds a certain set value during autocruise. The purpose is to obtain a highly reliable alarm without causing chattering.

<Means for Solving the Problems> The configuration of the present invention that achieves the above object includes a first determining means for determining whether or not the vehicle is traveling in autocruise; a second determining means for determining whether or not the alarm means is in operation when it is determined that the warning means is in operation;
As a result of the determination by the determination means, when it is determined that the warning means is not in operation, a value obtained by adding a first predetermined value ΔV ₁ to the set vehicle speed V ₀ for auto cruise driving is compared with the current vehicle speed V of the vehicle. third determination means for operating the alarm means when V>V ₀ +ΔV ₁ ;
As a result of the determination by the second determining means, if it is determined that the warning means is in operation, a second predetermined value ΔV ₂ that is slightly smaller than the first set value ΔV ₁ is added to the set vehicle speed V ₀ . and a fourth determining means for comparing the current vehicle speed V with the current speed V of the vehicle and stopping the warning means when V<V ₀ +ΔV ₂ .

<Examples> Examples of the present invention will be described in detail below based on the drawings. FIG. 1 is an electrical circuit diagram when the present invention is applied to a vehicle equipped with a manual transmission equipped with an autocruise function using an electronic governor controlled by a microcomputer, and FIG. 2 is a flowchart of this operation.

As shown in FIG. 1, a lamp 3 serving as an alarm means
3 and the buzzer 34 are operated by the CPU 11 via the lamp drive circuit 31 and the buzzer drive circuit 32. At this time, the CPU 11 uses the signal from the auto cruise setting device 20 to determine whether auto cruise is in progress and whether the lamp 33 and buzzer 34 are operating. In response to the signal representing the current vehicle speed, determine the magnitude relationship between the current vehicle speed V and the value obtained by adding the first predetermined value ΔV ₁ to the set vehicle speed V ₀ or the value obtained by adding the second predetermined value ΔV ₂ to the set vehicle speed V ₀ are doing. At this time, the set vehicle speed V ₀ is the auto cruise setting device 2.
It is set as the vehicle speed detected by the vehicle speed sensor 22 when auto cruise driving is set by 0.
13. Moreover, the first predetermined value ΔV ₁ is
V ₀ + ΔV ₁ is the upper limit of vehicle speed that is considered safe from the viewpoint of danger prevention, and the second predetermined value ΔV ₂ is V ₀ +
The values are set so that ΔV ₂ is slightly smaller than V ₀ +ΔV ₁ and stored in the ROM 12, respectively.

Note that parts in FIG. 1 that are the same as those in FIG. 4 are given the same numbers, and redundant explanations will be omitted.

Next, the operation of the above embodiment will be explained using the flowchart shown in FIG. As shown in the figure,
The CPU 11 determines in decision block 40 whether or not autocruise is in progress. As a result, if the result is NO, the normal control 41 is performed, while if the result is YES, the lamp 33 and the buzzer 3 are
4 is in operation. As a result
If NO, decision block 43 determines that V>V ₀ +ΔV ₁
Determine whether or not. As a result, if NO, the current vehicle speed V is within the safe range for auto-cruise driving with the set value V ₀ , so the cruise control 44 continues as it is, while if YES, the auto-cruise driving with the set value V ₀ continues. The current vehicle speed V has increased to a dangerous speed, so lamp 33
And the buzzer 34 is activated 45. If the result of the determination at decision block 42 is YES, then it is determined at decision block 46 whether or not V<V ₀ +ΔV ₂ . If the result is NO, it means that the current vehicle speed V has not decreased enough, so the lamp 33 and the buzzer 34 continue to operate, while if YES, the current vehicle speed V has decreased sufficiently. This means that the lamp 33 and buzzer 34
The operation is stopped 47. In this way ΔV ₁ > ΔV ₂
By setting this, even if the current vehicle speed V fluctuates within a small range with V ₀ + ΔV ₁ as the boundary, lamp 3
3 and the buzzer 34 can be prevented from chattering.
This ΔV ₁ is, for example, 5 Kg/h, and ΔV ₂ is, for example, 3
Set to Kg/h.

In addition, in the above embodiment, the current vehicle speed V is the set value.
Although we only considered the case where V becomes larger than ₀ , in order to perform a good auto cruise, it is better to issue a warning even when the current vehicle speed V drops to an unfavorable level with respect to the set value V ₀ . . Incidentally, an example of a case where the current vehicle speed V falls below the set value _V0 is when the vehicle approaches a slope. When considering the lower limit value of the current vehicle speed V for auto-cruise, decision block 43 determines that V ₀ −ΔV ₁ ≦V≦V ₀ +
Decision block ₄₆ determines whether ΔV ₁ or not.
Determine whether ΔV ₂ <V<V ₀ +ΔV ₂ , respectively,
If the determination block 43 is NO, the lamp 33 and buzzer 34 may be activated.

<Effects of the Invention> As specifically explained above in conjunction with the embodiments, according to the present invention, if the vehicle speed exceeds the set value during autocruise and increases to a level that is unfavorable for safety, the alarm means is activated. This allows the driver to know this and prevent accidents from occurring.
Further, since the vehicle speed is different between the time when the warning means is activated and the time when the warning means is stopped, the warning means does not cause chattering.

[Brief explanation of drawings]

Fig. 1 is an electric circuit diagram showing an embodiment of the present invention, Fig. 2 is a flowchart thereof, Fig. 3 is a schematic diagram of the control rack and its surroundings, and Fig. 4 is an electronic governor with an auto cruise function. FIG. In the drawing, 7 is a rack position sensor, 10 is an electronic governor control unit, 11 is a CPU, 33 is a lamp, 3
4 is a buzzer.

Claims (1)

[Claims] 1. A first determination means that determines whether the vehicle is running on autocruise, and when the first determining means determines that the vehicle is running on autocruise, it determines whether or not an alarm means is in operation. a second determining means; and as a result of the determination by the second determining means, if it is determined that the warning means is not in operation, a first predetermined value ΔV ₁ is set for the set vehicle speed V ₀ for auto cruise driving.
Compare the value added with the current vehicle speed V and find that V>V ₀
+ΔV ₁ , the third determining means activates the warning means, and as a result of the determination by the second determining means, if it is determined that the warning means is in operation, the _first fourth determining means for comparing a value obtained by adding a second predetermined value ΔV ₂ , which is slightly smaller than the set value ΔV ₁ , and the current vehicle speed V of the vehicle, and stopping the warning means when V<V ₀ +ΔV ₂ ; A vehicle overspeed warning device for auto cruise, characterized by comprising: