JPH07332446A - Gear shift control device for continuously variable transmission - Google Patents

Abstract

PURPOSE:To perform gear shift control of most suitable power performance according to demanding acceleration by performing interpolation according to the change speed of a throttle opening by using a gear shift pattern where importance is attached to fuel consumption and a gear shift pattern where importance is attached to power performance. CONSTITUTION:A control device 1 for a continuously variable transmission comprises a car speed sensor 2 to detect a car speed; a throttle sensor 3 to detect a throttle opening as an engine load; a second gear shift map to decide the target input number of revolutions different from a first gear shift map wherein the target input number of revolutions is decided from a car speed and a throttle opening and a control means 4 to decide the target input number of revolutions by performing interpolation of the first target input number of revolutions, determined by a change gear map 1 of a type where importance is attached to fuel consumption and a second target input number of revolutions determined from a gear shift map of a type where importance is attached to a power by means of a car speed and a throttle opening according to a signal correlated to the change speed of a throttle opening.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for a continuously variable transmission.

[0002]

2. Description of the Related Art As a conventional control device for a continuously variable transmission,
The one described in Japanese Patent Application Laid-Open No. 58-18066 is known. In the above-mentioned publication, in a shift control method for a continuously variable transmission, a gear ratio when the accelerator pedal depression amount (a signal correlating with an engine load) rapidly increases is made larger than gear ratios in other cases. , A shift control method for adjusting a gear ratio when the accelerator pedal depression amount rapidly increases. Further, in claim 2 of the above-mentioned publication, in the shift control method according to claim 1 of the above-mentioned publication, when the accelerator pedal depression amount is rapidly increased, the gear ratio is corrected by using the changing speed of the accelerator pedal depression amount as a variable. A shift control method that is determined by a function that

This is to improve acceleration performance when an acceleration request is made by controlling so that a gear ratio larger than a preset gear ratio is obtained according to the speed of change of the accelerator pedal depression amount, that is, the acceleration request. It is what makes me. Further, in the above publication, data of two different gear ratio command signals respectively corresponds to any one of the throttle opening of the engine, the negative pressure of the intake pipe, and the fuel supply amount (corresponding to the engine load. Corresponding to the vehicle speed signal) and the vehicle speed signal are stored in the memory. Unless the accelerator pedal depression amount is rapidly increased, the data of the gear ratio command signal on the small gear ratio side is searched and the accelerator pedal is depressed. A control method is described in which a gear ratio command signal on the higher gear ratio side is retrieved when the amount of depression is rapidly increased.

This is provided with a shift pattern that emphasizes fuel efficiency performance and a shift pattern that emphasizes power performance. When acceleration is requested, shift control is performed by a pattern that emphasizes power performance, and normally, a shift pattern that emphasizes fuel economy is performed. By performing the control, both the power performance at the time of acceleration request and the fuel efficiency performance at the normal time are made compatible.

[0005]

However, in the above-mentioned conventional shift control method for the continuously variable transmission, the gear ratio is increased as compared with the gear ratio in the normal state in accordance with the changing speed of the accelerator pedal depression amount. Although the power performance is improved as compared with the case of the normal gear ratio, there is a problem that the increased gear ratio is not always the best power performance according to the vehicle speed or the throttle opening.

Further, in the conventional shift control method for the continuously variable transmission, the shift pattern emphasizing power performance is optimal when the changing speed of the throttle opening is maximum, so that the changing speed of the throttle opening is not maximum. If it does not exist, there is a problem that optimal shift control is not performed even if the shift pattern is switched. Further, in order to solve the above problem, three or more shift patterns having different power performances according to the changing speed of the accelerator pedal depression amount are provided, and one shifting pattern is selected according to the changing speed of the accelerator pedal depression amount. Although a control method of performing the control may be considered, there is a problem that the memory amount increases.

The present invention has been made in view of the above problems, and in a shift control device for ensuring both fuel efficiency performance and power performance, a fuel consumption-oriented gear shift pattern and a power performance-oriented gear shift pattern are provided. The purpose is to perform shift control of the most suitable power performance according to the required acceleration by performing interpolation according to the changing speed of the throttle opening.

[0008]

In order to solve the above-mentioned problems, in a shift control device for a continuously variable transmission according to claim 1 of the present invention, a vehicle speed sensor for detecting a vehicle speed, means for detecting an engine load, A fuel efficiency-oriented shift map that determines the target input speed so that the fuel efficiency performance is the best with a signal that correlates with vehicle speed and engine load, and the one that has the best power performance with a signal that correlates with vehicle speed and engine load And a power-oriented shift map that determines the target input speed so that the target input speed is obtained. The first target input rotation speed obtained from the shift map and the second target rotation speed obtained from the power-oriented shift map are interpolated according to a signal correlated with the changing speed of the engine load. And configured to determine the target input rotational speed by.

Further, in the shift control device for a continuously variable transmission according to a second aspect of the present invention, the shift control means has an interpolation map for determining an interpolation amount for interpolating the shift map according to a signal correlated with a changing speed of the engine load. Then, the first target input rotation speed obtained from the first shift map and the second target input rotation speed obtained from the second shift map are obtained from the interpolation map based on the signal that correlates with the vehicle speed and the engine load. The target input rotation speed is determined by performing interpolation according to the interpolation amount.

[0010]

According to the above structure, in the shift control device for the continuously variable transmission according to the first aspect of the present invention, the first target input rotation speed determined by the fuel consumption-oriented shift map based on the signal correlated with the vehicle speed and the engine load. And the second target input speed determined by the power-oriented shift map are interpolated according to the signal correlated with the changing speed of the engine load to determine the target input speed.

Further, in the shift control device for a continuously variable transmission according to a second aspect of the present invention, the first target input speed and power-oriented shift map obtained by the fuel consumption-oriented shift map based on a signal correlating with vehicle speed and engine load. The target input rotation speed is determined by interpolating the second target input rotation speed calculated by the above equation in accordance with the interpolation amount calculated by the interpolation map.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows a control device 1 for a continuously variable transmission, which includes a vehicle speed sensor 2 for detecting a vehicle speed Vs, a throttle sensor 3 for detecting a throttle opening Th as an engine load, and a target input rotation based on the vehicle speed Vs and the throttle opening Th. Number Pr
a first shift map for determining i1 and a second shift map for determining a target input rotational speed Pri2 different from the first shift map based on the vehicle speed Vs and the throttle opening Th. The first target input rotation speed Pri obtained by the fuel economy-oriented shift map from Th
Control means for determining the target input speed Pri by interpolating 1 and the second target input speed Pri2 obtained from the power-oriented shift map according to the signal dTh correlated with the changing speed of the throttle opening Th. It is composed of 4.

Further, the control means 4 has an interpolation map for determining an interpolation amount for interpolating the shift map according to the signal dTh correlated with the changing speed of the throttle opening Th, and the vehicle speed Vs and the throttle opening Th are used for the control. By interpolating the first target input rotation speed Pri1 obtained by the fuel consumption tree thin shift map and the second target input rotation speed Pri2 obtained by the power-oriented shift map according to the interpolation amount obtained by the interpolation map. The target input rotation speed Pri is determined.

Further, the fuel efficiency-oriented shift map determines the target input rotational speed Pri1 so that the fuel consumption characteristic is the best, based on the vehicle speed Vs and the throttle opening Th, and the power-oriented shift map is the vehicle speed. The target input rotation speed Pri2 is determined by Vs and the throttle opening Th so that the power characteristic becomes the best. In addition,
FIG. 2 shows a fuel efficiency-oriented shift map, FIG. 3 shows a power-oriented shift map, and FIG. 4 shows an interpolation map.

The control contents in this embodiment will be described below with reference to the flow chart shown in FIG. Step SP1
Then, the controller 4 controls the throttle sensor 3 at every time interval t.
The signal of the throttle opening Th is read. At the same time, the vehicle speed Vs is read from the vehicle speed sensor 2.

At step SP2, the throttle opening Th
Is 0, the interpolation coefficient k is reset to 0. In step SP3, the change rate dTh of the throttle opening is calculated from the current throttle opening Th and the previous throttle opening Th ′ by the equation (1). dTh = Th-Th '... (1) In step SP4, the interpolation coefficient k is obtained using dTh according to the interpolation map of FIG.

At step SP5, the interpolation coefficient is obtained by the equation 2 from the current interpolation coefficient k and the previous interpolation coefficient k '. k = k + k '(2) At step SP6, if k is larger than 1, k is set to 1
And In step SP7, when k is smaller than -1, k is set to -1.

In step SP8, from the vehicle speed Vs and the throttle opening Th, the first target input rotational speed Pri1 is determined by using the fuel consumption-oriented shift map of FIG. The target input rotation speed Pri2 is calculated, and the target input rotation speed Pri is calculated by the equation 3. Pri = Pri1 + k * (Pri2-Pri1) (3) Next, a specific example of the above-described calculation of the target input speed Pri will be described. The signal of the throttle opening Th is read at time t = 0.1 seconds, and the throttle opening Th is changed as shown in FIG. First, throttle opening Th until time a
Since = 0, the interpolation coefficient k becomes 0. Time b (b =
a + 0.1), the throttle opening degree Th = 2/8, so the change speed dTh of the throttle opening degree Th is 2/8 according to the equation 1. Here, the interpolation coefficient k is 0.1 according to the interpolation map of FIG. When the interpolation coefficient is calculated by the equation 2 from the current interpolation coefficient k = 0.1 and the previous interpolation coefficient k ′ = 0, k = 0.1. Here, when the vehicle speed Vs = 50 Km / h, the first target input revolution speed Pri1 is calculated from the throttle opening Th = 2/8 by using the fuel consumption-oriented shift map of FIG.
= 2000 rpm, the second target input rotation speed Pri2 = 3000 rpm is obtained using the power-oriented shift map of FIG.
00 rpm is obtained.

Throttle opening Th = 2/8 until time c
Therefore, the changing speed dTh of the throttle opening Th becomes 0 according to the equation 1. Here, according to the interpolation map of FIG.
The interpolation coefficient k becomes 0. When the interpolation coefficient k is calculated by the equation 2 from the current interpolation coefficient k = 0 and the previous interpolation coefficient k ′ = 0.1, k = 0.1. Vehicle speed Vs = 50km /
If h is set, the first target input speed Pr is calculated from the throttle opening Th = 2/8 by using the fuel consumption priority type shift map of FIG.
i1 = 2000 rpm, the second target input rotational speed Pri2 = 3000 rpm using the power-oriented shift map of FIG.
And the target input rotation speed Pri =
It is calculated as 2100 rpm.

Since the throttle opening Th = 5/8 at time d, the changing speed d of the throttle opening Th is calculated by the equation 1.
Th becomes 3/8. Here, the interpolation coefficient k is 0.15 according to the interpolation map of FIG. Interpolation coefficient k =
When the interpolation coefficient is calculated by the equation 2 from 0.15 and the previous interpolation coefficient k ′ = 0.1, k = 0.25. Here, when the vehicle speed Vs = 50 Km / h, the throttle opening Th = 5 /
From FIG. 8, the first target input speed Pri1 = 4000 rpm using the fuel economy priority shift map of FIG. 2 and the second target input speed Pri2 using the power priority shift map of FIG.
= 5000 rpm, and the target input rotation speed Pri = 4250 rpm is calculated from the equation (3).

At time e (e = f + 0.1), the throttle opening degree Th = 2/8, so the change rate dTh of the throttle opening degree Th becomes -3/8 according to the equation (1). Here, the interpolation coefficient k is -0.15 according to the interpolation map of FIG. When the interpolation coefficient k is calculated from the current interpolation coefficient k = −0.15 and the previous interpolation coefficient k ′ = 0.25 by Equation 2,
k = 0.1. Here, with the vehicle speed Vs = 70 Km / h and the throttle opening Th = 2/8, the first target input rotational speed Pri1 = 2 is obtained using the fuel consumption-oriented shift map of FIG.
The second target input speed Pri2 = 3200 rpm is obtained using 100 rpm and the power-oriented shift map of FIG.
It can be calculated as 0 rpm.

According to the above control, the throttle opening Th
When the change speed dTh of is smaller than 1/8, the interpolation coefficient maintains the previous value. Further, the throttle opening Th =
At 0, the interpolation coefficient becomes 0, so the throttle opening Th =
0 and when the change rate dTh of the throttle opening Th = 0 from 0 is changed to be smaller than ⅛, the shift control is performed according to the fuel efficiency-oriented shift map. Further, when the changing speed dTh of the throttle opening Th is larger than 7/8, shift control is performed according to the power-oriented shift map of FIG.

Therefore, when acceleration is not requested, the shift control is performed so that the fuel consumption characteristic becomes the best according to the fuel consumption-oriented shift map. When acceleration is requested, the power characteristics are improved by interpolating between the fuel efficiency-oriented shift map and the power-oriented shift map according to the changing speed of the throttle opening. When a large acceleration is required, the power is changed according to the power-oriented shift map. Shift control is performed so that the characteristics are the best.

Further, in a control device which already has a fuel consumption-oriented shift map and a power-oriented shift map, it is sufficient to add an interpolation map that defines the speed of change of the throttle opening and the interpolation amount, so there are three maps. The memory amount can be reduced as compared with the control method for selecting the shift map described above. Although the throttle opening is used as the signal correlated with the engine load in the above-described embodiment, the present invention is not limited to this, and the suction pipe negative pressure, the fuel supply amount, and the like may be used.

[0025]

As described above, according to the shift control device for a continuously variable transmission according to the present invention, interpolation is performed between the fuel consumption-oriented shift map and the power-oriented shift map according to the changing speed of the engine load. As a result, when acceleration is not requested, the shift control is performed so that the fuel consumption characteristic becomes the best according to the fuel consumption priority type shift map, and when acceleration is requested, the power characteristic is improved according to the required acceleration and a large acceleration is achieved. When required, the shift control is performed according to the power-oriented shift map so that the power characteristic becomes the best. For this reason,
There is an effect that both fuel efficiency performance and power performance can be ensured, and when a large acceleration is required, the shift control that optimizes the power characteristics is surely performed.

Further, since the interpolation map defines the interpolation amount only in accordance with the changing speed of the engine load, the fuel consumption characteristic and the power characteristic can be obtained with a smaller memory amount as compared with the control method of selecting three or more shift maps. There is an effect that both can be made compatible.

[Brief description of drawings]

FIG. 1 Configuration of a control device for a continuously variable transmission

[Fig. 2] Fuel efficiency-oriented shift map

[Figure 3] Power-oriented shift map

[Figure 4] Interpolation map

FIG. 5: Flow chart

FIG. 6 is an explanatory diagram of control

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Control device for continuously variable transmission, 2 ... Vehicle speed sensor, 3 ... Throttle sensor 4 ... Control means

Claims (2)

[Claims] 1. A vehicle speed sensor that detects a vehicle speed, a means that detects an engine load, and a signal that correlates with the vehicle speed and the engine load determine the target input speed so that the fuel efficiency characteristic is the best. Type shift map and a power-oriented shift map that determines the target input speed so that the power characteristics are the best by the signal correlated to the vehicle speed and the engine load, and the target input speed is obtained. In a transmission control device for a continuously variable transmission that controls the gear ratio of a transmission, a first target input speed and a power-oriented shift map are obtained by a fuel consumption-oriented shift map based on a signal that correlates with vehicle speed and engine load. The second
And a target input rotation speed of the engine according to a signal that correlates with a changing speed of the engine load, thereby determining the target input rotation speed. 2. The shift control means has an interpolation map for determining an interpolation amount for interpolating the shift map according to a signal correlated with a changing speed of an engine load, and the fuel consumption priority is given by a signal correlated with a vehicle speed and an engine load. Target input rotation speed by interpolating a first target input rotation speed obtained by the type shift map and a second target input rotation speed obtained by the power-oriented shift map according to the interpolation amount obtained by the interpolation map. The shift control device for a continuously variable transmission according to claim 1, wherein: