JPS61235224A - Constant-speed driving gear for automobile - Google Patents

Abstract

PURPOSE:To let a device perform its shift-down before a car speed largely drops as well as to make constant-speed driving maintainable so effectively, by letting a transmission step shift-down when engine load is more than the specified value and deceleration in the car speed is above the specified value. CONSTITUTION:There are provided with a deceleration detecting device 1006 detecting the extent of deceleration in a car speed and a high engine load detecting device 1006 detecting a fact that engine load is more than the specified value, and these output signals are outputted to a controlling device 1008. With this controlling device 1008, a driving actuator 1002 of a throttle valve or the like controlling a fuel supply to an engine is controlled, for keeping the car speed to the setting one. And above-mentioned, when the engine load is more than the specified value and deceleration in the car speed is above the specified value, a shift-down device 1000 is operated, making a car transmission step shift down, whereby constant-speed driving is made so as to be maintainable.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a constant speed traveling device for an automobile that maintains the vehicle speed at a desired set vehicle speed and travels at a constant speed.

``Prior art and problems to be solved by the invention'' When a car is running, when the vehicle speed reaches a desired speed, the vehicle speed is memorized as a set vehicle speed by the operation of the occupant, and from then on, this set vehicle speed is A constant speed driving device that automatically controls the engine throttle valve to maintain a constant speed has been put into practical use.

As a constant speed running device for automobiles, for example, Japanese Patent Application Laid-Open No. 58-1
There is a device disclosed in Japanese Patent No. 92114, in which, in a vehicle with an automatic transmission equipped with a constant speed traveling device, when the actual vehicle speed is lower than the set vehicle speed by a predetermined value or more, and the vehicle is driven at a constant speed at the set vehicle speed. When the signal output to drive the vehicle is at its maximum (when the throttle opening is large), the gear of the automatic transmission is downshifted, so even when the vehicle speed drops as it approaches a hill while driving at a constant speed, The increased driving force allows the vehicle to continue traveling at the set speed.

However, in the conventional device described above, since the downshift is performed based on the vehicle speed, the reaction is slow, the vehicle speed drops significantly, and constant speed driving cannot be maintained.

SUMMARY OF THE INVENTION An object of the present invention is to provide a constant speed driving device for an automobile that has a quick response and can maintain constant speed driving by downshifting before the vehicle speed drops significantly.

[Means and operations for solving the problems] FIG. 1 shows a schematic configuration of a constant speed traveling device for an automatic vehicle according to the present invention.

In FIG. 1, a shift down means 1000 for downshifting the gear stage of an automobile, an actuator 1002 for controlling the amount of fuel supplied to the engine, a deceleration detecting means 1004 for detecting deceleration of the vehicle speed, High engine load detection means 1006 is provided to detect that the engine load is equal to or higher than a predetermined value.

The signals from the deceleration detection means 1004 and the high engine load detection means 1006 are transmitted to the control means 1008.
The control means 1008 controls the downshift means 1000 and the actuator 1002. That is, the control means 1008 controls the actuator 1002 to maintain the vehicle speed at the set vehicle speed, while
When the engine load detected by the high engine load detection means 1006 is equal to or higher than a predetermined value, and the deceleration detected by the deceleration detection means 1004, that is, how the vehicle speed decreases per unit time, is equal to or higher than a predetermined value. Then, the downshift means 1000 is operated.

"Example" Hereinafter, the present invention will be explained in detail based on the drawings.

Next, the circuit configuration of the constant speed traveling device according to the embodiment and the configuration of the actuator of the device will be explained based on FIG. 2.3.

As shown in FIG. 2, the constant speed running device includes a 1B circuit 3 led from a power source 1 via an ignition switch 2.
A control device 5 is connected to the main switch 4 via a main switch 4, and the control device 5 is equipped with a set switch 6, a coast switch 7, and a resume switch 8 as vehicle speed setting means.
and a signal from the vehicle speed sensor 9 are input, and signals are output from the control device 5 to the solenoids lla, 12a, and 13a of the actuator 10.

The set switch 6, the coast switch 7, and the resume switch 8 are connected between the control device 5 and the ground.
is the vehicle speed indicated by the signal from the vehicle speed sensor 9 or, for example, 4
When the vehicle speed reaches a desired speed in the range of 0 to 1100 k/h, turning it on will set the vehicle speed at that time as the set vehicle speed for constant speed driving.

Further, the coast switch 7 is used when decelerating the vehicle while traveling at a constant speed, and when it is turned on, the vehicle speed decreases. Further, 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, based on the operation of these switches 6, 7, 8 and the signal from the vehicle speed sensor 9, the solenoid lla of the actuator 10 is activated from the control device 5.

Signals are output to 12a and 13a to maintain, decelerate, or restore the vehicle speed.

Further, in this constant speed traveling device, a shift switch 14 as a constant speed traveling canceling means for canceling constant speed traveling control and a brake switch 15 are arranged in parallel between the power supply circuit 3 and the control device 5. and these switches 14
．． 15 is turned ON when the shift lever is operated and when the brake is operated, respectively, to input a release signal to the control device 5. A solenoid 40 for canceling constant speed running is provided, and this solenoid 40 is connected to the control device 5 via a transistor 41.

Next, the structure of the actuator 10 will be explained. As shown in FIG. 3, the actuator 10 is a negative pressure diaphragm type actuator, and the casing 16
The inside is defined into a negative pressure chamber 18 which is made airtight to the outside by a rubber diaphragm 17, and an atmospheric chamber 20 which is communicated with the outside by a through hole 19, and the diaphragm 17 is A solenoid valve for introducing negative pressure is provided on the end face of the casing 16 to control the introduction of negative pressure into the negative pressure chamber 18, and is biased toward the atmospheric chamber 20 by a spring 21 disposed in the negative pressure chamber 18. 11 and 11th 2nd
The structure includes atmosphere introduction solenoid valves 12 and 13 (the second atmosphere introduction solenoid valve 13 is not shown).

A rod 22 connected to the diaphragm 17
is slidably held by a bearing portion 23 provided in the casing I6, and is projected to the outside 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 the inlet direction (towards the negative pressure chamber 18), the throttle valve 25 is operated in the opening direction.

Further, the negative pressure introduction solenoid valve 11 has one end connected to a negative pressure introduction pipe 26 led from a negative pressure source, and
The valve body 11 connects the passage 111b whose other end communicates with the inside of the negative pressure chamber 18.
The valve body 1 is designed to open and close at c.
1C is pressed and biased by a spring lid to block the passage 11bjc, and the solenoid lla
When energized, the passage 11b resists the spring lid.
will be moved to open it. Similarly, the first atmosphere introduction solenoid valve 12 (the second atmosphere introduction solenoid valve 1
3) also has one end open to the atmosphere, and
The other end of the passage 12b communicates with the inside of the negative pressure chamber 18 through the valve body 12.
The valve body 12c is tension-biased by a spring 12d to open the passage 12b, and when the solenoid 12a is energized,
The passage 12b is blocked against the spring 12d.

Then, the solenoids lla, 12a, and 13a in these solenoid valves 11, 12, and 13 are energized and controlled by a signal from the control device 5 shown in FIG. is controlled, and the diaphragm 17 is displaced in accordance with this negative pressure, so that the throttle valve 25
The opening degree of the opening is controlled.

Next, the specific operation of the above device will be explained.

During normal driving, the vehicle speed is, for example, 40 to 1100 km.
/h, if you turn on the cent switch 6 connected to the control device 5 of the constant speed traveling device, the current vehicle speed indicated by the signal from the vehicle speed sensor 9 will be set as the set vehicle speed in the control device 5. At the same time, from then on, while comparing this set vehicle speed and the actual vehicle speed indicated by the signal from the vehicle speed sensor 9, a signal is output from the control device 5 to the actuator 10 so as to match the actual vehicle speed with the set vehicle speed. be done.

In other words, when the actual vehicle speed becomes lower than the set vehicle speed, the control device 5
An energization signal is output from the actuator 10 to the solenoid valves lla and 12a of the negative pressure introduction solenoid valve 11 and the first atmosphere introduction solenoid valve 12, the negative pressure introduction solenoid valve 11 opens, and the first atmosphere introduction solenoid valve opens. 12 closes.

Therefore, negative pressure is introduced into the negative pressure chamber 18 of the actuator 10, and the diaphragm 17 is displaced in the A direction, and accordingly, the throttle valve 25 is operated in the opening direction via the rod 22 and wire 24. Ru. 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 lla 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 in the negative pressure chamber 18 is reduced.

Therefore, the diaphragm 17 is displaced in the direction opposite to A, and the throttle valve 25 is operated in the closing direction, thereby reducing the actual vehicle speed to match the set vehicle speed.

In addition, during such constant speed running control, the solenoid 13a of the second atmosphere introduction solenoid valve 13 is constantly energized, and the liquid valve 13 is maintained in a closed state.

Further, when the shift 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 lla, 12a, and 13a is all stopped, and the solenoid valve 11 for introducing negative pressure is turned on. closed, and the first and second atmosphere introduction solenoid valves 12.13 opened,
By opening the inside of the negative pressure chamber 18 to the atmosphere, the operation of the actuator 10 is completely stopped, and the throttle valve 25 of the engine is operated by operating the accelerator pedal.

Next, in FIG. 2, a throttle opening detection means 28 is provided to detect that the throttle opening of the engine is greater than or equal to a predetermined value. It is connected to device 5. Note that the throttle opening detection means 28 corresponds to high engine load detection means.

Then, the control device 5 controls the actuator 10 to maintain the vehicle speed at the set vehicle speed, while the throttle opening detected by the throttle opening detection means 28 is equal to or higher than a predetermined value, and the vehicle speed sensor 9 When the deceleration calculated from the vehicle speed detected by is greater than a predetermined value,
Activate downshift means (not shown).

Timing chart of ' Next, the operation of the embodiment will be explained based on the timing chart of FIG.

In FIG. 4, as time t passes, the throttle opening increases and the vehicle speed deceleration 1dν/dtl increases, and at time tA, the throttle opening is larger than a predetermined value and the vehicle speed is decreasing. Since the deceleration 1 dV/dtl is greater than or equal to the predetermined value, the shift signal changes from rHJ to rLJ, the downshift means is activated, and the gear stage is downshifted.

Flowchart Next, FIG. 5 shows a flowchart according to an embodiment.

Set in step 100, set shift flag F=0 in step 102, drive at constant speed in step 106, input engine load (throttle opening) in step 108, and check whether the engine load is large in step 110. investigate.

If the engine load is not large in step 110, the process proceeds to step 112, and if F=0 in step 112, the process returns to step 106.

If the engine load is large in step 110, step 1
In step 14, a deceleration of 1 dV/dtl is input, and in step 118, it is checked whether the deceleration of vehicle speed l dV/dtl is larger than a predetermined value.

If ldv/dtl>Kr is not found in step 118, step 1064. :Return. On the other hand, if laV/dtl>Kte, it is checked in step 119- whether F=O.

If F=O in step 119, the shift is down in step 120, F=1 in step 122, and the process returns to step 106.

Thereafter, if F=1, the process returns from step 119 to step 106.

After that, if the engine load is not large in step 110,
The process proceeds to step 112, and if it is F-1 in step 112, it is shifted up in step 124, and in step 12
6, F=0, and the process returns to step 106.

"Effects of the Invention" As described above, according to the present invention, since deceleration is used to downshift, the reaction is faster than in the case of vehicle speed detection, and the You can downshift and maintain constant speed driving.

In the above embodiment, since the present invention is applied to a gasoline engine, the high engine load detection means is a throttle opening detection means, but in the case of a diesel engine, the high engine load detection means is a fuel injection This is used as a means for detecting the amount of fuel injected from the pump.

Further, as means for detecting deceleration, there are means for determining deceleration from vehicle speed and means for directly determining deceleration.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a constant speed traveling device according to the present invention, FIG. 2 is a circuit diagram of a constant speed traveling device according to an embodiment, FIG. 3 is a sectional view of an actuator in the device, and FIG. 4 FIG. 5 is a timing chart diagram showing the operation according to the embodiment. FIG. 5 is a flowchart diagram showing the operation according to the embodiment. 5...Control device, 6...St switch, 9...
Vehicle speed sensor, 10...actuator, 11a, 12
a, 13a... solenoid, 16... casing,
17...Diaphragm, 18...Negative pressure chamber, 20...
・Atmospheric chamber, 21... Spring, 22... Rod,
25... Throttle valve, 28... Throttle opening and output means. Figure 1 Figure 4 tAt

Claims (1)

[Scope of Claims] A shift down means for downshifting the gear stage of an automobile; an actuator for controlling the amount of fuel supplied to the engine; a deceleration detection means for detecting deceleration of vehicle speed; a high engine load detection means for detecting that the vehicle speed is above a predetermined value, and controlling an actuator to maintain the vehicle speed at a predetermined vehicle speed; A constant speed traveling device for an automobile, comprising: a control means for operating the downshifting means when the deceleration detected by the deceleration detection means is equal to or higher than a predetermined value.