JPH0572304B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a constant speed cruise control device for a vehicle equipped with an automatic transmission (A/T), and particularly to a constant speed cruise control device for a vehicle equipped with an automatic transmission (A/T), and particularly for controlling frequent shifting (busy) by the automatic transmission on an uphill road. The aim is to prevent this shift.

[Conventional technology]

Recent A/T cars have a 4-speed A/T with O/D (1 speed,
2nd, 3rd, and 4th speeds (O/D) are the mainstream, and approximately 50
At vehicle speeds of Km/h or higher, the vehicle normally runs in O/D (overdrive). However, in the case of automatic drive driving, it is difficult to drive at a constant speed with O/D on a steeply climbing road, resulting in a reduction in vehicle speed. Therefore, an O/D cut signal is output from the auto drive ECU and the O/D
The system uses a method that reduces vehicle speed reduction by increasing the driving force.

For example, as shown in Figure 2a, the vehicle speed is set to the target vehicle speed.
When the VM drops by A (for example, 4 km/h), turn on the O/D cut signal. This O/D cut signal is sent to the automatic shift controller to limit its gear selection. In other words, even in the case where the automatic shift controller determines that the vehicle is in the O/D range, there is a function that prohibits the selection and downshifts to 3rd speed.
This function works when the vehicle speed is VM-B (e.g. B=2Km/h)
However, the O/D cut signal is not required if the O/D return timer _returns to
14 seconds) have elapsed. This is to prevent frequent O/D cuts and returns from being repeated when the vehicle speed returns quickly.

[Problem that the invention seeks to solve]

By the way, the automatic transmission controller has its own shift pattern and determines the gear position based on the relationship between the throttle opening and the vehicle speed. If the control system is independent in this way, when the auto drive ECU opens the throttle valve as the vehicle speed decreases when climbing a slope, the transmission side will O/D cut may be performed. This is the VM-C shown in Figure 2b. As a result, when the vehicle speed increases, the autodrive ECU returns the throttle valve, so the transmission returns to O/D according to the shift pattern. At this time, since the transmission side does not have a delay function such as an O/D recovery timer, O/D cut and recovery are repeated at a fast cycle (also called O/D hunting or busy shift).

The present invention attempts to prevent fast-cycle O/D hunting (busy shift) by limiting the shift pattern on the transmission side to one with few shift changes during constant speed control.

[Means for solving problems]

The present invention provides a constant speed cruise control device for an automatic transmission vehicle equipped with an automatic transmission controller having two or more types of shift patterns for switching transmission gears based on the relationship between vehicle speed and throttle opening.
A constant speed driving control function that controls the throttle opening according to the traveling vehicle speed and causes the vehicle to travel at a target vehicle speed, and a transmission that sends a signal to prohibit selection of the highest speed gear to the automatic transmission controller when the vehicle speed decreases. a constant speed driving controller having a transmission limiting function; and a circuit that receives a signal indicating that the constant speed driving controller is under constant speed driving control and switches the shift pattern of the automatic transmission controller to a pattern with less shift change. It is characterized by comprising the following.

[Effect]

FIG. 3 is an explanatory diagram of shift patterns, in which a is a normal pattern and b is a power pattern. In addition to this, there is also a pattern called an economy pattern or a manual pattern. The normal pattern is a pattern that emphasizes smoothness with few shift changes, and at around 80 to 100 km/h, which is the normal range of auto drive, the driver will not shift down to 3rd gear unless the accelerator is pressed to near full throttle. Furthermore, the economy pattern is a pattern that is equivalent to or slightly harder to downshift than the normal pattern, and the manual pattern is even more difficult to downshift.
On the other hand, since the power pattern emphasizes dynamism, downshifts are performed under conditions of low throttle opening.

In principle, a busy shift occurs even in the normal pattern, but in reality, before a downshift occurs due to the throttle opening, the O/O drive is activated from the autodrive side by reducing the vehicle speed by a predetermined amount (VM-A described above).
Since D-cut control is performed, short-cycle O/D
Hunting can be avoided. Therefore, in the present invention, during constant speed driving control, a pattern in which shift changes are unlikely to occur (normal if there are two types, normal and pattern) is forcibly selected to prevent busy shifting on the transmission side.

〔Example〕

FIG. 1 is a block diagram showing one embodiment of the present invention. First, an outline of a duty control type constant speed cruise control device will be explained with reference to FIG. In the figure, 1 is an autodrive ECU (constant speed running controller), and 2 is an electronically controlled automatic transmission controller (automatic speed change ECU). The autodrive ECU 1 controls the duty of the actuator 3 to adjust the opening degree of the throttle 4. On the other hand, for automatic transmission
The ECU 2 controls shift solenoids S1 and S2 of a transmission 5 (the main body is not shown) to change the gear stage.

The outline of the constant speed control operation is as follows. The ECU 1 detects the running vehicle speed based on a signal from a vehicle speed sensor equipped with a reed switch that is turned on and off by a magnet that rotates in proportion to the rotation of the vehicle drive shaft. ECU 1 memorizes the traveling vehicle speed when the set switch is turned on, and after turning it off, actuator 3
Control valve duty. When the control valve is ON, negative pressure is introduced, increasing the force generated by the diaphragm linked to the throttle SL. When OFF, atmospheric air is introduced and weakens the diaphragm generating force. During this time, release valve 6 is being controlled.
is turned on, cutting off the atmosphere. When a cancel signal (clutch switch (neutral start switch for A/T vehicles), parking switch, or brake switch) is input, both the control valve and release valve are turned OFF, and atmospheric air is introduced from both to quickly control the system. make it stop. If you turn on the resume switch after canceling, driving control at the previously memorized vehicle speed will be restored.

Generally, constant speed driving is often performed at a vehicle speed within the O/D range. However, since it takes time to recover the vehicle speed on an uphill road, ECU1 outputs an O/D cut signal.
Make ECU2 select 3rd speed.

If the automatic transmission ECU 2 of this example has two types of shift patterns as shown in Fig. 3a and b, and is manually selected using an external pattern select switch, then the automatic transmission ECU 2 as shown in Fig. 1
By connecting the brake relay 7, which is turned off by a signal indicating that the vehicle is running at a constant speed, in series with the pattern select switch, it is possible to forcibly switch to the normal pattern with fewer shift changes while the vehicle is running at a constant speed. In this example, a signal that turns on the release valve 6 is commonly used as a signal indicating that the vehicle is running at a constant speed, but this may also be an output from an indicator port that indicates that the vehicle is running at a constant speed. Further, changes such as interposing a driver to drive the relay 7 or replacing the relay with a transistor switch are optional. Furthermore, if there are three or more shift patterns, it may be switched to a pattern with fewer shift changes than the normal pattern.

〔Effect of the invention〕

As described above, according to the present invention, busy shifting of the transmission of an automatic transmission vehicle (A/T vehicle) on an uphill road can be prevented by adding a simple circuit.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention;
FIG. 2 is a conventional operating waveform diagram, FIG. 3 is an explanatory diagram of a shift pattern of an automatic transmission, and FIG. 4 is a system configuration diagram of a constant speed cruise control device. In the figure, 1 is a constant speed running controller, 2 is an automatic shift controller, 3 is an actuator, 4 is a throttle,
5 is a transmission, and 7 is a shift pattern switching relay.

Claims (1)

[Claims] 1 The shift pattern for changing transmission gears is determined based on the relationship between vehicle speed and throttle opening.
In a constant speed driving control device for an automatic transmission vehicle equipped with an automatic transmission controller having more than one type, a constant speed driving control function that controls the throttle opening according to the traveling vehicle speed and causes the vehicle to travel at a target vehicle speed; A constant speed driving controller having a transmission restriction function that sends a signal for prohibiting selection of the highest gear to the automatic transmission controller when the vehicle speed decreases; 1. A constant speed cruise control device for an automatic transmission vehicle, comprising: a circuit that receives a signal indicating that the automatic transmission controller changes a shift pattern of the automatic transmission controller to a pattern with less shift change.