JPH0344006B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a constant speed traveling device for a vehicle that maintains a vehicle speed at a set vehicle speed by controlling a throttle valve.

[Prior art]

Conventionally, as a device of this type, there has been a constant speed traveling device, the schematic diagram of which is shown in FIG. In the figure 1
2 is a speedometer flexible shaft that rotates at a constant ratio to a wheel drive shaft (not shown) of the transmission 1; 3 is a magnet 4 that rotates in synchronization with the flexible shaft 2; This is a speed detection section consisting of a reed switch 5 that generates pulses corresponding to the actual vehicle speed as the vehicle rotates. The pulses generated by the reed switch 5 corresponding to the actual vehicle speed are input to the control circuit 6, where they are counted at regular intervals. The number of pulses corresponding to the set vehicle speed is set in a vehicle speed setting circuit (not shown). Further, after the vehicle speed is set, this control circuit 6 compares the number of pulses corresponding to the above-mentioned set vehicle speed with the number of pulses corresponding to the continuously counted actual vehicle speed, and calculates the number of pulses at each vehicle speed control cycle. A speed increase signal 6a or a speed increase signal 6 that rotates the DC motor 7 in the normal direction for a certain ratio of the difference to increase the actual vehicle speed.
A reduction gear that outputs a deceleration signal 6b that reverses the DC motor 7 with the opposite polarity to that of the DC motor 7 and decelerates the actual vehicle speed, and that simultaneously sets the vehicle speed and consists of a worm 8a connected to the DC motor 7 and a worm wheel 8b that meshes with the worm wheel 8b. The coil 8c built in the worm wheel 8b of No. 8 is energized and energized. 9 is coil 8c
10 is an electromagnetic clutch plate that is attracted to the worm wheel 8b by energization, and 10 is fixed to the electromagnetic clutch plate 9 and connected to a throttle link 12 that rotates a throttle valve 11 in the intake manifold. This sector has a fan-shaped plate 10a around which the cable 13 is wound. The opening degree of the throttle valve 11 is controlled by the normal movement of the accelerator pedal 14 when driving other than at a constant speed, that is, during normal driving. Speed increase signal 6a
It is controlled by the rotational operation of the DC motor 7 based on the deceleration signal 6b. On the other hand, when the brake pedal or clutch pedal (not shown) of the vehicle is pressed while the vehicle is running at a constant speed, the control circuit 6 causes the coil 8c to
The energization is released and the electromagnetic clutch plate 9 is separated from the worm wheel 8b, thereby making it possible to cancel constant speed running at the set vehicle speed. Furthermore, after the constant speed running is canceled, the opening degree of the throttle valve 11 can be controlled by the normal movement of the accelerator pedal 14, allowing normal running.

The operation of the conventional constant speed traveling device configured as described above will be explained below. First, when a vehicle (not shown) is driven, the speedometer flexible shaft 2 of the transmission 1 rotates, and the magnet 4 rotates in synchronization with the flexible shaft 2.
As the magnet 4 rotates, pulses corresponding to the actual vehicle speed are generated from the reed switch 5 and are input to the control circuit 6, where the number of pulses is counted at regular intervals. For example, if the actual vehicle speed is 80 on a flat road.
When the constant speed running device is activated when the speed reaches Km/h, the actual vehicle speed of 80 Km/h becomes the set vehicle speed, and the throttle valve 11 is controlled to maintain this speed to perform constant speed running. That is, when the constant speed traveling device is activated, a pulse corresponding to the actual vehicle speed of the reed switch 5 counted by the control circuit 6 immediately before activation is set in a vehicle speed setting circuit (not shown), and the vehicle speed corresponding to this pulse is set as the set vehicle speed. becomes. In this case 80
Km/h is the set vehicle speed. At the same time, the coil 8c of the worm wheel 8b is energized by the control circuit 6, so that the electromagnetic clutch plate 9 is attracted to the worm wheel 8b, and the opening degree of the throttle valve 11 is maintained at the opening degree corresponding to the set vehicle speed. do. on the other hand,
The control circuit 6 operates a reed switch 5 according to the actual vehicle speed.
The generated pulses are counted at regular intervals, and the number of pulses corresponding to the actual vehicle speed and the set vehicle speed (80 km /
h) is compared with the number of pulses corresponding to
b is output and rotates the DC motor 7 for a fixed ratio of time. For example, when the vehicle speed decreases below the set speed due to an increase in running resistance during constant speed running, the control circuit 6 outputs a speed increase signal 6a to cause the DC motor 7 to rotate forward for a fixed ratio of time. Along with this, sector 1
0 rotates, the opening of the throttle valve 11 is increased by the action of the cable 13 connected to the throttle ring 12, and the amount of air-fuel mixture to be supplied into the cylinder of the engine (not shown) is increased to reach the set vehicle speed (80
km/h). On the other hand, when running resistance decreases during constant speed driving and the vehicle speed increases above the set speed, a deceleration signal 6b is output from the control circuit 6, causing the DC motor 7 to rotate in reverse for a fixed ratio of time, thereby controlling the opening of the throttle valve. Decrease the vehicle speed to the set vehicle speed (80
km/h). Furthermore, when the actual vehicle speed matches the set vehicle speed (80 km/h), the speed increase signal 6a and deceleration signal 6b of the control circuit 6 are not output, the DC motor 7 does not rotate, and the throttle valve 11 remains unchanged. Maintain opening.

However, according to such a conventional constant speed traveling device, the ratio between the number of pulses corresponding to the speed deviation between the set vehicle speed and the actual vehicle speed and the amount of change in the opening degree of the throttle valve 11 is limited to 80 km, which is often used on flat roads. The characteristics and energization time of the DC motor 7, the reduction ratio of the reducer 8, etc. are adjusted so that the constant-speed running control performance is optimized by taking into account the vehicle's acceleration-side gain and deceleration-side gain in the speed range of approximately /h. It has been decided that Therefore, when the vehicle runs uphill, the accelerating side gain decreases and the decelerating side gain increases as the running resistance of the vehicle increases, and conversely, when the vehicle runs downhill, the accelerating side gain decreases. Although the deceleration side gain decreases as the speed increases, the ratio between the number of pulses corresponding to the speed deviation and the amount of change in the opening of the throttle valve 11 is the same as that in the speed range of approximately 80 km/h on a flat road. As a result, the vehicle speed does not immediately increase relative to the set vehicle speed on uphill slopes, and does not immediately decrease relative to the set vehicle speed on downhill slopes, resulting in extremely poor speed control performance.

[Summary of the invention]

The present invention has been made in view of these points, and its purpose is to maintain the vehicle speed with extremely high speed control performance even when driving on a road with both uphill and downhill slopes. An object of the present invention is to provide a constant speed traveling device that can maintain a set speed.

In order to achieve such an object, the present invention provides a diode between a control circuit and a DC motor that has a positive polarity characteristic with respect to a speed increase signal, and a resistance change characteristic that is inversely proportional to a change in the throttle valve opening. A speed increasing side gain circuit is connected in series with a variable resistor having a variable resistor, and a diode having positive polarity characteristics with respect to the deceleration signal is connected in parallel to this speed increasing side gain circuit, and a change in the opening degree of the throttle valve is connected. A deceleration side gain circuit is connected in series with a variable resistor having a resistance change characteristic directly proportional to .

[Embodiments of the invention]

Hereinafter, the constant speed traveling device according to the present invention will be explained in detail.

FIG. 2 is a schematic diagram showing an embodiment of this constant speed traveling device. The same reference numerals as in FIG. 1 indicate the same parts, and the explanation thereof will be omitted. In the figure, reference numeral 15 denotes a speed-increasing side gain circuit connected between the control circuit 6 and the DC motor 7 and consisting of a series connection of a diode 15a and a variable resistor 15b, which have positive polarity characteristics with respect to the speed-increasing signal 6a. The resistance value of the variable resistor 15b is designed to change in conjunction with the change in the opening degree of the throttle valve 11.
1, the resistance value decreases as the opening degree increases, and the resistance value increases as the opening degree decreases, which is a so-called inversely proportional resistance change characteristic. Further, a deceleration side gain circuit 16 is connected in parallel to this speed increase side gain circuit 15, and this deceleration side gain circuit 16 has a reverse polarity characteristic with respect to the speed increase signal 6a, that is, a positive polarity with respect to the deceleration signal 6b. Diode 16 with characteristic characteristics
A and a variable resistor 16b are connected in series.

The resistance value of the variable resistor 16 is the same as that of the throttle valve 1.
1, and has a resistance change measurement that is directly proportional to the opening degree of the throttle valve 11.

Next, the operation of the constant speed traveling device configured as described above will be explained. When a vehicle (not shown) is driven and this constant speed traveling device is activated, the vehicle speed is set as in the conventional case, and a speed increase signal 6a is sent from the control circuit 6 to maintain the set vehicle speed according to the traveling condition.
Alternatively, the control circuit 6 to which the deceleration signal 6b is output
When the speed increase signal 6a is output, this signal returns to the control circuit 6 via the variable resistor 15b, the diode 15a, and the DC motor 7, and rotates the DC motor 7 in the forward direction for a fixed ratio of time to increase the actual vehicle speed. Speed up to bring the vehicle closer to the set speed. Furthermore, when the deceleration signal 6b is output, this signal is transmitted to the DC motor 7 and the diode 16.
a. Return to the control circuit 6 via the variable resistor 16b and reversely rotate the DC motor 7 for a fixed ratio of time;
Decrease the actual vehicle speed to bring it closer to the set vehicle speed. here,
For example, when the vehicle is running at high speed on a continuous uphill slope, the throttle valve 11 is opened to a wide opening, and in conjunction with this, the variable resistor 15b of the speed increasing side gain circuit 15 has a low resistance. On the contrary, the variable resistor 16b of the deceleration side gain circuit 16 has a high resistance. Therefore, the control circuit 6 sends a speed increase signal 6a.
When outputted, it is input to the DC motor 7 via the low resistance variable resistor 15b, and the DC motor 7 is rotated in the forward direction with a large current for a fixed ratio of time in accordance with the speed increase signal 6a. Conversely, when a deceleration signal 6b is output from the control circuit 6, it is input to the DC motor 7 via a high-resistance variable resistor 16b, and the DC motor 7 is reversely rotated with a small current for a fixed ratio of time according to the deceleration signal 6b. let Therefore, even if the actual vehicle speed decreases due to an increase in running resistance due to uphill traveling, and the time speed increase signal 6a of a fixed ratio is output in accordance with the decreased vehicle speed as in the past, the DC motor 7 is not driven by a large current. Since the throttle valve 11 is rotated, the throttle valve 11 can be opened with a wider variation than in the past, and the actual vehicle speed can be brought closer to the set vehicle speed quickly. Furthermore, even if the actual vehicle speed exceeds the set vehicle speed, the DC motor 7 is rotated with a small current for a fixed ratio of time, so the throttle valve 11 can be closed with a narrow opening change, significantly reducing the actual vehicle speed. There's nothing to do. On the other hand, when the vehicle is running on a continuous downhill slope, the throttle valve 11 has a narrow opening, and in conjunction with this, the variable resistor 16b of the deceleration side gain circuit 16 has a low opening. Conversely, the variable resistor 15b of the speed increasing side gain circuit 15 has a high resistance.
Therefore, when the deceleration signal 6b is output from the control circuit 6, it is input to the DC motor 7 via the low-resistance variable resistor 16b, and the DC motor 7 is reversed with a large current for a fixed ratio of time according to the deceleration signal 6b. Rotate.
Therefore, even if the actual vehicle speed increases due to the reduction in running resistance associated with downhill running, and the time deceleration signal 6b at a constant ratio is output in response to the increased vehicle speed, the DC motor 7 is rotated with a large current. The throttle valve 11 can be closed with a wider variation than in the past, and the actual vehicle speed can be quickly brought close to the set vehicle speed. Furthermore, even if the actual vehicle speed falls below the set vehicle speed, the throttle valve 11 rotates the DC motor 7 in the forward direction with a small current for a fixed ratio of time.
can be opened by small changes in the opening degree, and the actual vehicle speed will not be increased significantly. In this way, even if the output times of the speed increase signal 6a and deceleration signal 6b of the control circuit 6 are the same as in the conventional case, the current that drives the DC motor 7 is controlled depending on the running condition of the vehicle, and the throttle valve 11 is opened. Since the degree of change can be changed,
The speed control performance can be significantly improved compared to the conventional one.The resistance change characteristics of the variable resistor 15b of the speed-increasing gain circuit 15 and the variable resistor 16b of the decelerating-side gain circuit 16 are suitable for use on flat roads, uphill slopes, and The selection may be made so that the constant speed running control performance is optimized in consideration of the speed increase side gain and the deceleration side gain in an arbitrary speed range on a downhill slope.

〔Effect of the invention〕

As explained above, according to the constant speed traveling device according to the present invention, between the control circuit and the DC motor, there is provided a diode having a positive polarity characteristic with respect to the speed increase signal, and a resistance that is inversely proportional to the change in opening of the throttle valve. A speed-increasing gain circuit is connected in series with a variable resistor that has variable characteristics, and a diode that has positive polarity characteristics with respect to the deceleration signal and a throttle valve opening are connected in parallel to this speed-increasing gain circuit. Since we have connected a deceleration-side gain circuit consisting of a series connection with a variable resistor that has a resistance value characteristic that is directly proportional to the change in resistance, it is easier to operate than before even when driving on a road that has both uphill and downhill slopes. The vehicle speed can be maintained at a set speed with extremely high speed control performance.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing a conventional constant speed traveling device, and FIG. 2 is a schematic configuration diagram showing a constant speed traveling device according to the present invention. 6... Control circuit, 6a... Speed increase signal, 6b...
Deceleration signal, 7... DC motor, 11... Throttle valve, 15... Speed increase side gain circuit, 15a...
...Diode, 15b...Variable resistor, 16...
Deceleration side gain circuit, 16a...Diode, 16
b...variable resistor.

Claims (1)

[Claims] 1. A speed increase signal that compares a preset vehicle speed and an actual vehicle speed and increases the actual vehicle speed based on the comparison result, and a deceleration signal that decreases the actual vehicle speed with the opposite polarity to this speed increase signal. and a DC motor that changes the opening degree of a throttle valve by rotating in response to a speed increase signal and a deceleration signal of the control circuit. A diode having a positive polarity characteristic and a variable resistor having a resistance change characteristic inversely proportional to a change in the opening degree of the throttle valve are connected in series, and are connected between the control circuit and the DC motor. A speed increasing side gain circuit, a diode having a positive polarity characteristic with respect to the deceleration signal, and a variable resistor having a resistance change characteristic directly proportional to an opening degree change of the throttle valve are connected in series, and a speed increasing side gain circuit is connected in series. A constant speed traveling device equipped with a deceleration side gain circuit connected in parallel to the gain circuit.