JPS59126045A - Vehicle-speed controlling apparatus - Google Patents

Abstract

PURPOSE:To enable to control the vehicle speed with high accuracy and to detect troubles of a rotation sensor and a vehicle-speed sensor, by detecting the gear position of a transmission, calculating the vehicle speed on the basis of data relating to the gear position and data relating to the engine speed, and executing vehicle-speed control on the basis of the detected vehicle speed. CONSTITUTION:Outputs of a rotation sensor 4 and a vehicle-speed sensor 5 are applied to a CPU16 via I/F9, 14 and an I/O15, and the gear position of a transmission 10 is detected from the data relating to the engine speed and the data relating to the vehicle speed calculated at the CPU16. Further, the actual vehicle speed is calculated in the CPU16 from the data relating to the gear position and the data relating to the rotational speed, and a fuel control member of an internal combustion engine 2 is controlled to keep the vehicle speed at an aimed speed by controlling an actuator 20 on the basis of the data relating to the actual vehicle speed and the data relating to the aimed vehicle speed, read from a memory 17 in response to a control signal S4 given from a control panel 18. Further, on the basis of the gear ratio calculated from the data relating to the rotational speed and the data relating to the vehicle speed, judgement is made on whether trouble is caused with the sensor 4, 5.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle speed control device, and more specifically, to a vehicle speed control Kl device for controlling the speed of a vehicle using an internal combustion engine as a drive source to a desired speed.

In general, this type of vehicle speed control device is configured to control the engine speed so that the signal indicating the vehicle speed at any given time by the vehicle speed detector becomes the vehicle speed indicated by the signal or the value of jfr. However, conventional vehicle speed detectors that have been used for this purpose are composed of a reed switch and a magnet, and are configured to output a pulse signal at a frequency that corresponds to the rotating board of the vehicle speedometer cable. The vehicle speed control device is configured to control the vehicle speed in accordance with data indicating the vehicle speed value at each time calculated based on the period of this pulse signal. Although the vehicle speed detector with the above configuration is simple, it cannot accurately detect vehicle speed, and therefore,
The vehicle speed control rate is low, and the control response characteristics are not sufficient. In order to solve this problem, it would be possible to install a speedometer on the axle, but this would greatly increase the cost and pose an economical problem. Furthermore, in such a vehicle speed control device, it is necessary to detect a fault in a sensor that detects the vehicle speed or engine speed to ensure control safety. Another problem is that it is difficult to distinguish between cases where the sensor has failed and cases where the sensor has failed.

Therefore, an object of the present invention is to provide an internal combustion engine that can accurately control vehicle speed without installing an expensive vehicle speed sensor, and also that can reliably detect failures in the vehicle speed sensor and engine speed sensor. The purpose of the present invention is to provide a speed control device for locomotives.

The present invention provides a vehicle speed control device for controlling the traveling speed of a vehicle using an internal combustion engine as a drive source to a desired value.
A rotation sensor that outputs a rotation signal related to the rotation speed of the internal combustion engine, a vehicle speed sensor that outputs a vehicle speed signal related to the vehicle speed, and a detection means that detects a gear position of the transmission in response to the rotation signal and the vehicle speed signal. , a means for setting a desired target vehicle speed, a speed adjustment means for adjusting the speed of the internal combustion engine, and an actual vehicle speed is calculated based on the detection result and rotation signal from the detection means, and the target vehicle speed is obtained. control means for controlling the MiJ speed adjustment means; means for calculating a gear ratio of the transmission based on the rotation signal and the vehicle speed signal; and failure determination of the rotation sensor and the tL speed sensor based on the value of the gear ratio. It is characterized in that it is equipped with means for performing the following.

The control means calculates the product of the predetermined gear ratio and the machine-related concealment at the gear position detected by the detection means, compares the data representing the multiplication result with the data representing the target vehicle speed, and calculates the product based on the multiplication result. It is configured to control vehicle speed. According to this configuration, since the vehicle speed sensor is used only to detect the gear position as described above, high accuracy is not required. On the other hand, since vehicle speed is controlled based on the internal combustion engine speed and the gear ratio corresponding to the current gear position of the transmission, the accuracy of vehicle speed control depends on the accuracy of the rotation sensor that detects the rotational speed of the internal combustion engine. I will do it. Generally, the detection accuracy of a rotation sensor that detects engine speed is several steps higher than that of a vehicle speed sensor, so it is possible to construct a device with higher control accuracy than conventional vehicle speed control devices. Furthermore, by checking whether the gear ratio value obtained as described above is within a predetermined normal range, a failure detection system is constructed by mutual monitoring between the vehicle speed sensor and the rotation sensor. This significantly improves the reliability of the device.

Hereinafter, the present invention will be described in detail based on the illustrated embodiment. FIG. 1 shows a block diagram of an embodiment of a vehicle speed control device according to the present invention. The vehicle speed control device 1 is a device for controlling the vehicle speed of a vehicle 3 using an internal combustion engine 2 as a drive source to a desired target vehicle speed that is arbitrarily set.
A rotation sensor 4 for detecting the rotation speed of the internal combustion engine 2 and a vehicle speed sensor 5 for detecting the vehicle speed of the vehicle 3 are provided.

The rotation sensor 4 includes a signal gear plate 7 fixed to the crankshaft 6 of the internal combustion engine 2;
Each cog formed on the chest circumference of the signal gear plate 7 is connected to the electromagnetic coil 8.
This is a known sensor in which a voltage is induced in the electromagnetic coil 8 each time the object approaches or moves away from the object. Therefore, the rotation sensor 4 outputs an output at a time interval related to the rotation speed of the internal combustion engine 2.
The /4'rus sequence No. 11 SI consisting of the arm lass is output, and the corresponding interface circuit (Ilo) 9
After being waveform-shaped at , it is output as the first signal S2. On the other hand, the vehicle speed sensor 5 is connected to a meter cable (not shown) of a vehicle speedometer of a traveling device 110 that is connected to the internal combustion engine 2 via the transmission 10, and rotates as the meter cable rotates. It consists of a magnet grate 12 and a reed switch 13. As shown in the figure, the magnet plate 12 is alternately magnetized to N and S poles,
It rotates as the meter cable rotates, turning the reed switch 13 on and off. The reed switch 13 is connected to the input side of an interface circuit (I/F) 140, and the output side thereof outputs a second signal S3 whose level changes in response to the on/off state of the reed switch 13. . As can be seen from the above explanation, the period of the second signal S3 changes in relation to the vehicle speed! This is a pulse train signal.

The first signal S2 having information regarding the speed of the internal combustion engine 2 and the second signal S3 having information regarding the vehicle speed are input to an input/output circuit (Ilo) 15, where the respective periods of each signal are The first data D1 and the second data D2 are created as binary digital data. First data D indicating the period of the first signal S2 output in this way
1 and second data D2 indicating the period of the second number S3 are stored in the memory 17 by the central processing unit (CPU) 16.

The central processing unit 16 stores a program for controlling the vehicle speed to a predetermined target vehicle speed, and the control panel 1
The program is executed in response to a control signal S4 from each operation switch (not shown) provided at 8. In the central processing unit 16, the position of the fuel adjustment member required to bring the vehicle speed to the required target speed is determined based on each input data DI.
+ D2 + and the control signal S4, and the calculation result in the central processing unit 16 is a position signal S indicating the adjustment position of the fuel adjustment member (not shown) of the internal combustion engine 2.
6, the signal is output from the input device [15] and manually inputted to the drive circuit 19. A drive signal S6 is output from the drive circuit 19 in response to the position signal SS, and is applied to an actuator 20 connected to a fuel adjustment member (not shown), whereby the adjustment position of the fuel adjustment member is adjusted to the position signal S5. controlled accordingly.

FIG. 2 (IL) and FIG. 2(b) show a flowchart of the program for controlling the vehicle speed described above.

First, in step a, it is determined whether the control system shown in FIG. 1 is normal or not. If the control system is normal,
In step b, the second data D2 is read,
Store the second data D2 in the memory 17, and
It is checked whether the value of 2 is within a predetermined normal range (Stella 7'c). If there is an abnormality in the control system, proceed to step d, where the vehicle speed control is completely canceled and the cruise rung (not shown) provided in the control panel 18 (Fig. 1) is turned off (Stella 7'''). e)
.

If the determination result in step C is YES, then in step f, the value of vehicle speed ■ is calculated based on the second data D2. This calculation is performed by multiplying the reciprocal of the second data D2 by a predetermined coefficient, and data regarding the vehicle speed can be easily obtained. On the other hand, step C
If the calculation result in step g is No, first, step g
At this point, it is determined whether the vehicle is in a constant speed running control state or not, and if the determination result is NO, the process proceeds to step f.

If the determination result is YES, it is determined that the value of D2 is outside the normal range for a predetermined number of consecutive times N,
Stellar fh determines whether or not it has been detected. If the determination result in step h is NO, proceed to step f, and if YES, display that the vehicle speed sensor is malfunctioning (step I), and completely cancel the control (Stella 7'd). .

That is, if the value of the second data D2 is outside the normal range N times or more consecutively while driving at a constant speed, it is determined that the vehicle speed sensor is malfunctioning and the control is completely canceled. , otherwise, in step f, the vehicle speed is calculated based on the data D2.

The calculation result of the vehicle speed is 28kIT1/ in step j.
It is determined whether or not it is greater than or equal to h, and if the determination result is NO, the control is completely canceled. This is the vehicle speed or 28+n/h
If the vehicle is very slow, there is virtually no need to control the vehicle speed.
This is to forcibly release the control.

If the vehicle speed is 28 krV/h or more, the gear position is determined in step k.

The gear position is determined based on the vehicle speed V calculated in step f and the engine rotational speed N, which is separately calculated based on the first data D1. That is, vehicle speed ■ and rotational speed N
The gear ratio R is defined as the gear ratio RE: N/V
Therefore, RE:D, /D2. by the way,
The value of the gear ratio R is a unique value determined by the gear position in the transmission 10. If the gear position is R1 in the primary position, R8 in the binary position, and R3 in the tertiary position, Dl/ D
It is possible to determine the gear position at any given time. In this embodiment, the predetermined gear ratio R+lR for each gear position
2 and R3, respectively, in the first gear ratio region 1. A second gear ratio region n1 and a third gear ratio region ■ are respectively established, and D I /D
It is configured to determine which gear ratio range the value of 2 falls in, and to detect the gear position at that time based on this result. Different gear ratio regions (A), (B), (C), etc. are set at both ends of each gear ratio region, and stripes are formed in which region the values of D I, /D 2 are. The gear position and the abnormality of the vehicle speed sensor are determined depending on whether the gear ratio R or the vehicle speed sensor is abnormal or not. After the performance and the gear position determination, it is determined in step t whether or not the vehicle is traveling at a constant speed. If the vehicle is not traveling at a constant speed, it will proceed directly to Stella 7'm, but if it is traveling at a constant speed, it will be determined whether or not the vehicle speed sensor is malfunctioning based on this calculated gear ratio. It is executed by n to q. That is, in step m, it is determined whether or not the gear ratio is normal (whether or not the gear ratio belongs to the range (a) to (a) shown in FIG. 3). If the determination result is NO, the gear ratio is further adjusted. It is determined whether the ratio abnormality condition has been detected a predetermined number of times N2 consecutively, and if it is determined that the ratio is abnormal N2 times in a row, the control is completely canceled. In this way, by checking whether the gear ratio is normal or not, it is possible to determine a failure through mutual monitoring between the rotation sensor 4 and the vehicle speed sensor 5, which has the advantage of improving control reliability. There is. If the determination result in step p is No, proceed to Stella 7''m.

If it is determined that the gear ratio is normal, further
In step 0, it is determined whether or not the gear position determined in step k has changed. If a change in the gear position is not detected, the process proceeds to step m. On the other hand, if a change in the gear position is detected, In Stella fq, it is determined whether the gear position has changed continuously a predetermined number of times N3. In this case, it is normally impossible to perform a gear change operation in which a change in gear position is detected N3 times in a row. is completely released (step d). On the other hand, even if there is a change in the gear position, if there is no change N3 times in succession, the vehicle speed sensor is considered to be normal, and the process proceeds to step m.

If at least one of the determination results in steps p and q is YES, the process proceeds to step d via step rf to indicate a failure of the vehicle speed sensor;
It may be configured to completely release the control.

Step m is a step in which the vehicle speed V is calculated from the gear position determined in step 1 and the rotational speed #N calculated in advance. Here, the value of the vehicle speed V is detected by the rotation sensor 4. It is calculated with the same precision as the rotational speed, and is not directly related to the output of the vehicle speed sensor 5. That is, since the rotational speed #N detected with high precision is converted into the vehicle speed VK in consideration of the determination result in step k, it is possible to detect the vehicle speed with high precision.

When the value of vehicle speed ■ is calculated in this way,
Check the status of each switch in the control channel 18 (
According to the results, the control is temporarily canceled (step t), and the PI control is performed so that the vehicle speed value obtained above becomes the desired target vehicle speed (step u).
X:! generates a ramp function (ste,,7' v
). If the temporary release has been performed, the process proceeds to step e. In addition, after the rung function is generated in step V, the process proceeds to step U, where PI control calculations are performed, and then, in step W), a check is made to see if a gear slippage has occurred. It is carried out (Stella 7°X). Check for gear slippage can be performed, for example, by monitoring whether the value of gear ratio R has become abnormally large. Even in this case, the determination result in step If it is detected that (
Stella fy) Completely release control. If such a Stella 7" (z is installed), by monitoring the gear position during constant speed driving, it is possible to detect that a gear change has been made even if the clutch switch fails, and cancel constant speed driving. However, it also has the advantage of being able to prevent the engine from blowing up.If gear slippage is not detected, or if it is detected but not detected N4 times in a row,
Proceed to step 2.

Step 2 is to determine the target value QdrIve of the fuel supply amount according to the accelerator operation amount and the value Qcruls of the fuel supply amount necessary to make the vehicle travel at a constant speed at each time.
This is a step in which the larger data value is compared with e and the larger data value is used as position control data indicating the target position of the fuel adjustment section. The position control data obtained in this way is outputted as a position signal S5 via the input/output device 15.

According to such a configuration, the gear position of the transmission 1o is determined from the vehicle speed information obtained from the vehicle speed sensor 5 and the engine speed information obtained from the rotation sensor 4, and the gear position obtained in this way is determined. Since the vehicle speed is calculated from the information and the engine speed information, the accuracy of the obtained vehicle speed information is almost the same as the detection accuracy of the rotation sensor 4. As a result, even if a conventional inexpensive vehicle speed sensor that obtains vehicle speed information from the rotational speed of the rotating cable of the vehicle speedometer is used as the vehicle speed sensor 5, extremely accurate vehicle speed information can be obtained. In addition to being able to control vehicle speed with high precision, control responsiveness is also significantly improved. The gear position can be determined based on the ratio between the engine speed and the vehicle speed. Therefore, when used for this purpose, the detection accuracy of the vehicle speed sensor may be low, and the conventional vehicle speed sensor described above may not be used. Is it possible to achieve that goal? Therefore, the vehicle speed can be controlled accurately without using an expensive vehicle speed sensor.

Furthermore, in the above embodiment, whether the gear ratio is normal or abnormal in step n is determined based on whether the gear ratio R is in any of the ranges (a) to (a). The range can be determined as appropriate by considering the accuracy of the vehicle speed sensor, etc.

According to the present invention, the gear position of the transmission is detected directly or indirectly, the vehicle speed is calculated based on the gear position information and the engine rotation speed information, and the vehicle speed is controlled based on the calculated vehicle speed. Since this is done, the vehicle speed can be accurately controlled to a desired vehicle speed without using an expensive vehicle speed sensor, and control responsiveness is also improved. In addition, by checking whether the gear ratio calculated from the information from the vehicle speed sensor and the information from the rotation sensor is within the normal range specified by the DI, mutual monitoring between the vehicle speed sensor and the rotation sensor is performed. A failure detection system can be configured, and the reliability of the device is significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a program diagram showing an embodiment of a vehicle speed control device according to the present invention, and FIGS. 2(a) and 2(b) are flowcharts of a control program loaded into the device of FIG. FIG. 3 is an explanatory diagram for explaining how to determine whether the calculated gear ratio value is normal or abnormal. DESCRIPTION OF SYMBOLS 1... Vehicle speed control device, 2... Internal combustion engine, 3... Vehicle, 4... Rotation sensor, 5... Vehicle speed sensor, 10...
...Transmission, 11... Traveling device, 15... Input/output device, 16... Central processing unit, 19... Drive circuit, 2
0... Actuator, Sl... Relay train signal, Sl
...First number, S3...Second signal, S4...Control signal, S5...Position signal, DI...First data, D
? ...Second data. Patent applicant: Diesel Equipment Co., Ltd.

Claims (1)

[Claims] 1. A vehicle speed control device for controlling the traveling speed of an axle driven by an internal combustion engine to a desired value, which includes a rotation sensor that outputs a rotation signal related to the rotation speed of the internal combustion engine, and a rotation sensor that outputs a rotation signal related to the rotation speed of the internal combustion engine. A vehicle speed sensor that outputs a speed signal,
a detection means for detecting the gear position of the transmission in response to the rotation signal and the vehicle speed; a means for setting a desired target vehicle speed; a speed adjustment means for adjusting the speed of the internal combustion engine; control means for calculating the actual vehicle speed based on the detection result from the detection means and the rotation signal and controlling the speed adjustment means so as to obtain the target vehicle speed; A vehicle speed side (e) device characterized by comprising means for calculating a gear ratio of a transmission, and means for determining failure of a front mc rotation sensor and the vehicle speed sensor based on the value of the gear ratio.