JPS62143740A - Constant speed running device for automobile - Google Patents

Abstract

PURPOSE:To provide specified acceleration irrespective of the magnitude of a loading weight, by a method wherein a means is provided for detecting the loading weight of an automobile, and the gain of control of constant speed running by means of a car speed control means is changed according to a loading weight. CONSTITUTION:An actual car speed detected by a car speed detecting means B1 is compared with a set car speed by a car speed control means B2, a signal is outputted to a fuel feed means B3 to control a fuel feed amount, and the actual car speed is adjusted approximately to a set car speed. Meanwhile, a signal from a loading weight detecting means B4 is inputted to a control gain regulating means B5, and a signal by means of which the gain of control of constant speed running by means of a car speed control means B2 is outputted according to the loading weight. This constitution enables provision of acceleration which is always constant irrespective of the magnitude of a loading weight.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a constant speed traveling device for an automobile that maintains the vehicle speed at a desired set value and causes the vehicle to travel at a constant speed.

(Prior Art) In recent years, constant speed driving devices have been put into practical use that automatically maintain the vehicle speed of an automobile at a desired speed set by the driver. This constant speed traveling device sets the vehicle speed as a target value for constant speed traveling by a set operation by the driver when the vehicle speed reaches a desired vehicle speed, and thereafter compares this set vehicle speed with the actual vehicle speed. Therefore, when a difference occurs between the two, the throttle valve of the engine is controlled according to the difference, thereby making the actual vehicle speed match the set vehicle speed. An example of such a constant speed traveling device is disclosed in Japanese Utility Model Application No. 57-164228.

The constant speed traveling device is operated by the driver while the vehicle is running, and there are four types of operations: vehicle speed setting operation, acceleration operation, deceleration operation, and vehicle speed return operation. Vehicle speed setting operation is an operation that maintains the current vehicle speed as it is by pressing the set switch, etc. Acceleration operation is an operation that gradually increases the set vehicle speed by holding down the acceleration switch (accelerator switch). ,
When you release your hand from the acceleration switch, the vehicle maintains constant speed at that current speed. Note that the same switch is used as the set switch and the acceleration switch, and pressing the switch once will cause the vehicle to travel at a constant speed, while continuing to press the switch will increase the set vehicle speed for the constant speed traveling. Deceleration operation is the opposite of acceleration operation, and is an operation that gradually decreases the set vehicle speed during this time by holding down the deceleration switch (coast switch), and vehicle speed return operation is an operation in which constant speed driving is canceled in response to brake and clutch operation. In this case, by pressing the vehicle speed return switch (resume switch), the vehicle speed is returned to the vehicle speed before release, and the vehicle is driven at a constant speed.

When such a constant speed traveling device is installed on a vehicle, when increasing the vehicle speed by operating the acceleration switch or vehicle speed return switch, differences in the size of the vehicle loading weight such as the weight of passengers and luggage etc. The degree of acceleration varies depending on the This means that even if the amount of fuel supplied to the engine is controlled the same and the rate of increase in driving force due to this fuel supply is also the same, the difference in vehicle weight due to the difference in loaded weight will cause the acceleration for the same driving force to change. This is because they are different.

If the acceleration differs depending on the size of the loaded weight, the feeling of acceleration when driving at a constant speed will change each time, which may cause problems such as an undesirable feeling for the driver. be.

(Object of the Invention) In view of the above problems, an object of the present invention is to provide a travel control device that can always obtain constant acceleration regardless of the size of the loaded weight.

(Configuration of the Invention) The configuration of the constant speed traveling device for an automobile of the present invention will be explained based on the block diagram of FIG. 3.

This constant speed traveling device compares the actual vehicle speed detected by the vehicle speed detection means B1 with the set vehicle speed in the vehicle speed control means B2, and outputs an operating signal from the vehicle speed control means B2 to the fuel supply means B3 to open/close the throttle valve, etc. The amount of fuel supplied to the engine is controlled by controlling the amount of fuel supplied to the engine so that the actual vehicle speed approaches the set vehicle speed.Meanwhile, the loaded weight detection means B4 detects the loaded weight of the vehicle.
The control gain adjustment means B5 receiving the signal from the vehicle outputs a signal to the vehicle speed control means B2 to change the gain of the constant speed running control by the vehicle speed control means B2 according to the loaded weight,
It is characterized in that a constant acceleration can always be obtained regardless of the loading Im.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the constant speed traveling device has a controller 5 connected via a main switch 4 to a power supply circuit 3 led from an electric current m1 via an ignition switch 2. Signals from the accelerator switch 6, coast switch 7, and resume switch 8 as vehicle speed setting means and signals from the vehicle speed sensor 9 are input to the controller 5, and the actuator 10 is inputted from the controller 5.
A signal is output to the solenoids 11a, 12a, and 13a. Here, the controller 5 plays a role as a vehicle speed control means, and is composed of a microcomputer, and includes various arithmetic processing units (CPUs),
A read-only memory (ROM) that contains the control program and a read-only memory (RA) that temporarily stores various data.
M).

The accelerator switch 6, the coast switch 7, and the resume switch 8 are connected between the controller 5 and the ground. Among these switches, the accelerator switch 6 also functions as a set switch, and is connected to the vehicle speed sensor 9. For example, if the vehicle speed indicated by the signal is 40~
By operating the ON operation when the desired vehicle speed is within the range of 1007 m/h, the vehicle speed setting function sets the vehicle speed at that time as the set vehicle speed for constant speed driving, and by maintaining the ON state, During this time, the set vehicle speed is increased, and when the vehicle is turned off, it has an acceleration function that causes the vehicle to travel at a constant speed at this increased vehicle speed. Further, the coast switch 7 is used to decelerate the vehicle while traveling at a constant speed, and when it is turned on, the set vehicle speed decreases. In general, when the constant speed driving control is canceled due to a reason other than the OFF operation of the main switch 4, the resume switch 8 is turned ON to return the vehicle to the set vehicle speed before the cancellation. Then, the solenoid 11a of the actuator 10 is activated from the controller 5 based on the signals from the operation of these switches 6, 7, and 8 and the signal from the vehicle speed sensor 9.

Actuation signals are output to 12a and 13a to maintain, accelerate, decelerate, or return the vehicle speed.

Further, in this constant speed traveling device, a clutch switch 14 and a brake switch 15 are placed in parallel between the power supply circuit 3 and the controller 5 as constant speed traveling canceling means for canceling the constant speed traveling control. These switches 14 and 15 are turned on when the clutch is disengaged and when the brake is applied, respectively, to input a release signal to the controller 5 and cause the controller 5 to release the constant speed driving control.

Also connected to the controller 5 is a loaded weight detection means 30 for detecting the vehicle loaded t[I, so that loaded weight information is sent to the controller 5. Therefore, when the accelerator switch 6 or the resume switch 8 is operated and acceleration is required, the controller 5 operates the actuator 10 to control the throttle opening, increasing the amount of fuel supplied to the engine and accelerating. The controller 5, which has received the loaded weight information, adjusts the acceleration control gain in accordance with this weight 1, so that a constant acceleration can be obtained regardless of the amount of il. In other words, when the loaded weight is large, the control gain is increased to increase the fuel supply increase rate, and when the loaded weight is small, the control gain is decreased to decrease the fuel supply increase rate, regardless of the loaded weight. This allows constant acceleration to be obtained.

Next, to explain the structure of the actuator 10, as shown in FIG. 2, the actuator 10 is a negative pressure diaphragm type actuator, and the inside of the casing 16 is airtight from the outside by a rubber diaphragm 17. The diaphragm 11 is defined into a negative pressure chamber 18 and an atmospheric chamber 20 communicated with the outside through a through hole 19.
A negative pressure introduction solenoid valve 11 is provided on the end face of the casing 16 to control the introduction of negative pressure into the negative pressure chamber 18. and 1st. The structure includes second atmosphere introduction solenoid valves 12 and 13 (the second atmosphere introduction solenoid valve 13 is not shown). The rod 2 connected to the diaphragm 17
2 is slidably held by a bearing part 23 provided in the casing 16 and protrudes outward through the atmospheric chamber 20, and is provided in the intake passage of the engine via a wire 24. connected to the throttle valve 25;
When the diaphragm 17 moves in six directions (towards the negative pressure chamber 18), the throttle valve 25 is operated in the opening direction.

Further, the negative pressure introduction solenoid valve 11 opens a passage 11b, which has one end connected to a negative pressure introduction pipe 26 led from a negative pressure source and the other end communicates with the inside of the negative pressure chamber 18, with the valve body 11c. This valve body 11 (j is pressed and biased by a spring 11d to shut off the passage 11b, and opens the passage 11b against the spring 11d when the solenoid 11a is energized. Similarly, the first atmosphere introduction solenoid valve 12 (the same applies to the second atmosphere introduction solenoid valve 13) has one end opened to the atmosphere and the other end opened to the negative pressure chamber 18.
The valve body 120 is tension-biased by a spring 12d to open the passage 12b, and the spring 12d is biased when the solenoid 12a is energized. The passage 12b is blocked off against the flow. The solenoids 11a, 12a, and 13a of these solenoid valves 11, 12, and 13 are energized by signals from the controller 5 shown in FIG. 1, so that the negative pressure in the negative pressure chamber 18 of the actuator 10 is reduced. The opening degree of the throttle valve 25 is controlled by displacing the diaphragm 17 in accordance with this negative pressure.

Next, the specific operation of the above-mentioned actuator will be explained.

For example, when driving normally, the vehicle speed increases from 40 to 100! R
/h, when the accelerator switch 6 connected to the control device 5 of the constant speed traveling device is turned on, the vehicle speed at that time indicated by the signal from the vehicle speed sensor 9 is set in the controller 5 as the set vehicle speed. Thereafter, the controller 5 outputs a signal to the actuator 10 to match the actual vehicle speed with the set vehicle speed while comparing the set vehicle speed with the actual vehicle speed indicated by the signal from the vehicle speed sensor 9.

In other words, when the actual vehicle speed becomes lower than the set vehicle speed, the controller 5 outputs an energization signal to the solenoids 11a and 12a of the negative pressure introduction solenoid valve 11 and the atmosphere introduction solenoid valve 12 in the actuator 10, thereby introducing negative pressure. solenoid valve 11 opens, and first solenoid valve 12 for introducing atmospheric air closes. Therefore, negative pressure is introduced into the negative pressure chamber 18 of the actuator 10, and the diaphragm 17 is displaced in the backward direction, and the throttle valve 25 is operated in the opening direction via the rod 22 and the wire A724, and the engine is The amount of fuel supplied will increase. As a result, the actual vehicle speed increases and becomes equal to the set vehicle speed. On the other hand, when the actual vehicle speed is higher than the set vehicle speed, the solenoids 11a and 12a are not energized, so that the negative pressure introduction solenoid valve 11 is closed and the first atmosphere introduction solenoid valve 12 is opened, so that the negative pressure The negative pressure within chamber 18 is reduced. Therefore, the diaphragm 11 is displaced in the opposite direction, the throttle valve 25 is operated in the closing direction, and the amount of fuel supplied to the engine is reduced, thereby reducing the actual vehicle speed to match the set vehicle speed. still,
During such constant speed running control, the solenoid 13a of the second atmospheric air introduction solenoid valve 13 is constantly energized and the valve 13 is maintained in a closed state. Further, when the clutch switch 14 or the brake switch 15, which serves as a means for canceling the constant speed running control, is turned on, the energization to the solenoids 11a, 12a, and 13a is all stopped, and the negative pressure introduction solenoid valve 11 is closed. And first. Second
The solenoid valves 12 and 13 for introducing atmospheric air are opened and the negative pressure chamber 1B is opened.
By opening the inside to the atmosphere, the operation of the actuator 10 is completely stopped, and the throttle valve 2 of the engine is opened to the atmosphere.
5 is activated by operating the accelerator pedal.

Further, when the accelerator switch 6 or the resume switch 8 is operated and acceleration is required, an energization signal is sent from the controller 5 to the solenoids Ila and 12a of the negative pressure introduction solenoid valve 11 and the atmosphere introduction solenoid valve 12 in the actuator 10. is output, the negative pressure introduction solenoid valve 11 opens, and the atmosphere introduction solenoid valve 1 opens.
At this time, the controller 5 adjusts the vehicle speed control gain according to the signal from the loading M port inspection means 30, and controls the opening speed of the solenoid valve to close the negative Controls the introduction speed of negative pressure into the pressure chamber,
Adjust the displacement speed of the diaphragm 17. The opening degree of the solenoid valves 11 and 12 is controlled by controlling the duty ratio of the energization of the solenoid and by controlling the amount of movement caused by the energization of the solenoid.By controlling the displacement speed of the diamond through this control, fuel is supplied to the engine. By adjusting the supply increase rate, it is possible to always obtain constant acceleration regardless of the loaded weight. The rate of increase in fuel supply to the engine can be adjusted by adjusting the vehicle speed control gain not only when accelerating with the operation of the accelerator switch or resume switch, but also when adjusting the actual vehicle speed during normal constant speed driving control. The same applies to acceleration when the vehicle speed becomes lower than the set vehicle speed.

The details of control by the controller 5 in the constant speed traveling device described above will be explained with reference to the flowchart of FIG. 4.

In this control starting from step $1, first in step S2, Kl is read as the value of the control gain G, and using this value 1, constant speed driving control is performed. As mentioned above, this constant speed driving control compares the set vehicle speed and the actual vehicle speed, and increases the throttle valve opening if the actual vehicle speed is lower than the set vehicle speed, and conversely, if the actual vehicle speed is higher than the set vehicle speed. In this method, the actuator is controlled to reduce the opening degree of the throttle valve so that the actual vehicle speed approximately matches the set vehicle speed. Note that when the accelerator switch is pressed, the set vehicle speed will increase during this time, and the actuator will accelerate the vehicle so that the actual vehicle speed will match this increased set vehicle speed.

When performing such constant speed driving control, step S4
The loaded weight of the vehicle is detected in step S5, and it is determined in step S5 whether this loaded weight W is larger than a predetermined type IWs. When W>WS, K is the value of control gain G.
z (>Kt) is read and constant speed driving control is performed based on this value. On the other hand, in the case of WSWs, the control gain remains at 1 and constant speed running control is performed. As a result, when the amount of loaded molds exceeds a predetermined weight and sufficient acceleration cannot be obtained, the control gain is increased to prevent the acceleration from decreasing too much. In the above case, the control gain is adjusted in two stages by comparing the loaded weight with a predetermined weight, but as shown in the graph of Fig. 5, the control gain is adjusted according to the magnitude of the loaded weight W. The gain may be determined so that constant acceleration can always be obtained.

(Effects of the Invention) As explained above, according to the present invention, in a constant speed traveling device that controls the amount of fuel supplied to the engine to perform constant speed traveling, the loaded weight of the vehicle is detected and Since the control gain is adjusted accordingly, constant acceleration can be obtained regardless of the size of the loaded weight, and good constant speed running can be achieved.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of a constant speed traveling device according to the present invention, Fig. 2 is a sectional view of an actuator in the device, Fig. 3 is a block diagram showing the configuration of the device, and Fig. 4 is a constant speed driving device by the device. FIG. 5 is a flowchart showing the details of travel control. FIG. 5 is a graph showing the relationship between the control gain used for control by the device and the loaded weight.

Claims (1)

[Claims] A vehicle speed detection means for detecting the actual vehicle speed; a fuel supply means for controlling the amount of fuel supplied to the engine; and a vehicle speed detection means for comparing the actual vehicle speed detected by the vehicle speed detection means with a preset vehicle speed. , a vehicle speed control means for controlling the operation of the fuel supply means so that the actual vehicle speed approaches the set vehicle speed and the vehicle runs at a constant speed; a loaded weight detecting means for detecting the loaded weight of the vehicle; and a loaded weight detecting means for detecting the loaded weight of the vehicle. 1. A constant speed traveling device for a motor vehicle, comprising: control gain adjusting means for changing the gain of constant speed traveling control by the vehicle speed control means according to the loaded weight.