JP3036967B2 - Transmission control device for continuously variable transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention reads out a control target value based on a preset control map and controls the speed ratio of the continuously variable transmission in accordance with the control target value. It concerns the device.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 58-180864
As can be seen in the publication, the control target value of the continuously variable transmission is read based on a minimum fuel consumption rate curve set in advance so that the fuel consumption rate is minimized, and the continuously variable transmission is controlled in accordance with the control target value. In a V-belt continuously variable transmission configured to control the speed ratio of a transmission, an actual acceleration is detected from a change in vehicle speed, and if the actual acceleration is smaller than a preset comparison reference acceleration, the speed change is performed. By using the gear ratio pattern on the larger side, it has been practiced to prevent power shortage or the like when climbing a hill due to heavy use of the low rotation speed side having good fuel efficiency.

[0003]

A control target value is read based on the minimum fuel consumption rate curve set in advance as described above, and the speed ratio of the continuously variable transmission is controlled in accordance with the value. Further, in the above-described conventional device, the control map including the minimum fuel consumption rate curve changes according to a change over time, a change in engine characteristics due to a change in outside air condition or a change in the type of gasoline used, or a variation in engine performance due to mass production. Therefore, when the control map does not match the actual situation, there is a problem that the fuel efficiency may be reduced.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problem, and a continuously variable transmission capable of appropriately controlling the speed ratio of a continuously variable transmission based on a control map set to always provide the best control state. It is an object of the present invention to provide a shift control device for a machine.

[0005]

The invention according to claim 1 is
Target value reading means for reading a control target value based on a control map in which a control target value corresponding to an operating state of the engine is set, and a shift drive for controlling a speed ratio of the continuously variable transmission according to the control target value And a control map in which a control target value is set in advance using the operating state of the engine and the fuel consumption rate as parameters .
And the operating state of the engine and the fuel consumption rate as parameters
Control target value is set, and the control target value
Priority control map with priority corresponding to consumption rate
A map storage means for storing up, and the fuel consumption rate calculation means for obtaining a fuel consumption rate depending on the operating conditions of the engine, control maps and priorities stored in the map storage means according to the calculated value of the fuel consumption rate A map updating means for updating the control map , wherein the operating state of the engine and the
Engine operation status based on the priority control map
Select the corresponding highest priority number and
The control target value corresponding to this priority number is
It is configured to be read from the loop .

According to a second aspect of the present invention, in the shift control device for a continuously variable transmission according to the first aspect , an acceleration detecting means for detecting an acceleration state of the vehicle, and when the vehicle is detected to be in an accelerated state. And target value correcting means for correcting the control target value read by the target value reading means to a range where the engine speed does not decrease.

[0007] The invention according to claim 3, in the shift control device for a continuously variable transmission according to claim 2, rate of change in the engine load by the acceleration detecting means, the control target value according to the rate of change of the engine load The correction range is set.

[0008]

According to the first aspect of the present invention, the control target value of the continuously variable transmission is read from the sequentially updated control map in accordance with the fuel consumption rate calculated by the fuel consumption rate calculation means, and the best target is always obtained. The speed ratio control of the continuously variable transmission is executed based on the latest data set so as to obtain the fuel efficiency. The fuel efficiency is calculated by the fuel efficiency calculating means.
The priority control map updated sequentially according to the fuel consumption rate
The control target value is read from the
And continuously variable transmission to obtain the best fuel efficiency
The speed ratio control of the machine is executed quickly and properly.
You.

According to the second aspect of the present invention, when the speed ratio control of the continuously variable transmission is executed when the vehicle is in an accelerating state, the engine speed does not decrease and the vehicle speed is reduced. Deterioration of running feeling is prevented.

According to the third aspect of the present invention, when the vehicle is in a rapid acceleration state or the like, the control target value is set within a range in which the engine speed is set higher in advance in accordance with the state of the vehicle. As a result, the gear ratio control more appropriate for the acceleration state is executed.

[0011]

FIG. 1 shows a continuously variable transmission 1 according to an embodiment of the present invention.
1 shows a drive system of a vehicle provided with the shift control device of FIG.
The continuously variable transmission 1 includes an input shaft 5 connected to a crankshaft 3 of an engine 2 via an electromagnetic clutch 4 and an output shaft for transmitting a driving force to a final reduction gear 7 connected to driving wheels 6 of the vehicle. 8, a drive pulley 9 and a driven pulley 10 attached to the input shaft 5 and the output shaft 8, and a conduction belt 11 wound around the pulleys 9 and 10.

By changing the effective diameters of the pulleys 9 and 10 by means of a shift driving means 12 comprising a hydraulically operated shift control valve, a speed change ratio comprising a rotational speed ratio between the input shaft 5 and the output shaft 8 is obtained. Is changed steplessly. Note that a structure using a fluid coupling, a torque converter, a centrifugal clutch, or the like may be used instead of the electromagnetic clutch 4.

The speed change driving means 12 adjusts the line hydraulic pressure or the flow rate supplied to the drive pulley 9 and the driven pulley 10 in accordance with a control signal output from a speed change control device, so that the two pulleys 9 and 10 are controlled. The effective diameter is adjusted so that the speed ratio of the continuously variable transmission 1 matches the target value. The shift control device includes a detection signal of a rotation speed sensor 13 for detecting an engine rotation speed ESP, a detection signal of a throttle sensor 14 for detecting a throttle opening TVO, and a fuel flow detection means for detecting a fuel flow per unit time. The control unit 16 reads a target gear ratio corresponding to the operating state of the engine 2 based on the detection signal of No. 15 and performs feedback control so that the actual gear ratio of the continuously variable transmission 1 matches the target gear ratio. I have.

That is, as shown in FIG. 2, the control unit 16 includes an engine speed ESP in which the throttle opening TVO and the fuel consumption rate (ratio of fuel consumption per unit horsepower) are set as parameters. Map storage means 17 for storing the control target value as a control map as shown in FIG. 3 and target value reading means 18 for reading the control target value from the control map in accordance with the detection signal of the throttle sensor 14 are provided. ing. And as described below
The operating status of the engine and the following priority control map
The target value reading means 18 controls the rotation of the engine.
A control target value consisting of numbers is read out, and a shift command signal corresponding to the control target value is output from the target value reading means 18 to the shift drive means 12, whereby the feedback control is executed. .

FIG. 4 shows a priority control map in which priorities are assigned according to fuel consumption rates calculated or measured in advance for each throttle opening TVO divided into a predetermined area in the control map. The smaller the fuel consumption rate, the higher the priority is assigned, and the numerical value of the priority is set to a smaller value. Further, the control target value of the priority control map is partitioned with a map number m for each predetermined area, and the map number m is set so that the number increases as the engine speed ESP increases. ing.

The control unit 16 includes a fuel consumption rate calculating means 19 for calculating a fuel consumption rate in accordance with a detection signal of the fuel flow rate detecting means 15, and a fuel consumption rate calculating means 19 for controlling the fuel consumption when the vehicle is in a steady running state which will be described later. Map updating means 20 for updating the control map based on the calculated value of the consumption rate; acceleration detecting means 21 for detecting the acceleration state of the vehicle according to the change state of the throttle opening TVO; There is provided a target value correcting means 22 for correcting the control target value read from the control map by the reading means 18 within a range where the engine speed ESP does not decrease.

The control operation of the control unit will be described with reference to the flowchart shown in FIG. When the control operation starts, in step S1, the rotation speed sensor 1
3. Throttle sensor 14 and fuel flow detecting means 15
The detected values of the engine speed ESP, the throttle opening TVO, and the fuel flow rate Q per unit time are input according to the detection signal. Next, in step S2, after executing the update control for updating the control map and the priority control map as described later, in step S3, the current engine speed ES is updated from the updated priority control map.
The map number m corresponding to P is read.

Thereafter, in step S4, it is determined whether or not the rate of change (dTVO / dt) of the throttle opening TVO is equal to or greater than 0, that is, whether or not the vehicle is currently in an acceleration state or a steady state. If NO is determined in this step S4 and it is confirmed that the vehicle is in a deceleration state,
In step S5, a high-priority number within a range equal to or less than the map number m is selected in an area corresponding to the current throttle opening TVO. For example, if it is confirmed that the area corresponding to the current throttle opening TVO and the map number m is in the area marked with * in FIG. Select number 1.

If YES is determined in step S4 and it is confirmed that the vehicle is in an accelerating state or a steady state, in step S6, the rate of change (dTVO / dt) of the throttle opening TVO is reduced. On the basis of this, a correction value n for correcting the control target value to the high speed side is obtained. That is, as shown in FIG. 6, from the map set in advance so that the correction value n increases as the change rate (dTVO / dt) of the throttle opening TVO increases, the change rate (dTVO
/ Dt) is read out.

In step S7, the corrected map number r is calculated by adding the correction value n to the map number m corresponding to the current engine speed ESP read in step S3. Then, in step S8, in the area corresponding to the current throttle opening TVO, the priority order within the range of the map number r or more is set.
Select a higher priority number . In the example of FIG.
If it is confirmed that the correction value n is 1, the area indicated by the mark * is slid by one block toward the high-speed side according to the correction value n, and has a higher priority within a range a. Object, ie, priority number 4 is selected.

In step S9, after reading out the control target value of the engine speed ESP corresponding to the priority number read out in step S5 or step S8,
In step S10, a target gear ratio is calculated based on the control target value of the engine speed ESP and the actual engine speed ESP, and in step S11, a control signal corresponding to the target gear ratio is output to the shift drive unit 12. I do.

Next, the control map updating routine in the above step S2 will be described with reference to the flowchart shown in FIG. When the update routine starts, first, in step S21, a moving average esp, tvo, te of the engine speed ESP, the throttle opening TVO, and the actual engine torque TE per unit time is calculated.
The actual engine torque TE is read from a map (not shown) or detected by a torque sensor (not shown) according to the operating state of the engine 3.

In step S22, based on the current engine speed ESP, the throttle opening TVO and the actual engine torque TE and the moving average esp, tvo, te, the fluctuation rate Xesp of the engine speed and the fluctuation of the throttle opening are calculated. The rate Xtvo and the fluctuation rate Xte of the actual engine torque are calculated. And steps S23 to S
25, the respective fluctuation rates Xesp, Xtvo, Xt
It is determined whether or not e is smaller than the reference values X1, X2, X3.

All the above fluctuation rates Xesp, Xtvo, X
te is smaller than the reference values X1, X2, X3, respectively.
If it is confirmed that the vehicle is in a steady running state,
In step S26, the actual fuel consumption rate BE is calculated based on the fuel flow rate Q per unit time detected by the fuel flow rate detecting means 18 and the actual engine torque TE and the engine speed ESP. That is, the shaft output He of the engine 3 is calculated based on the following equation (1) from the actual engine torque TE and the engine speed ESP, and the following equation (2) is obtained from the shaft output He, the fuel flow rate Q, and the fuel specific gravity ρ. ) Is calculated based on the actual fuel consumption rate BE.

He = (TE × ESP / 716.2) (1) BE = (Q × ρ × 10 3 / He) (2) Step S27 In the above, the actual fuel consumption rate BE
The control map shown in FIG. 3 is updated based on the calculated value of.
That is, the control map is updated by changing the value of the fuel consumption rate stored in the area of the current throttle opening TVO and the engine speed ESP to the calculated value. Next, in step S28, it is confirmed whether or not the priority order of the fuel consumption rate has changed according to the update of the control map. If the priority has changed, the priority control map is updated in step 29 by rewriting the priority so as to correspond to the changed state.

Since the control map stored in the map storage means 17 is sequentially updated in accordance with the fuel consumption rate calculated by the fuel consumption rate calculation means 19, the control target is always updated based on the latest data. Read the value,
Appropriate shift control corresponding to the control target value can be executed. Therefore, it is possible to prevent a situation in which the control map set to an appropriate state in the manufacturing stage does not conform to the actual situation in accordance with a change with time or the like, and it is possible to prevent the control target that minimizes the fuel consumption rate from the control map. By reading the value, it is possible to execute the speed ratio control of the continuously variable transmission 1 suitable for the running state of the vehicle and the operating state of the engine 2.

Further, in the above embodiment, the control map is updated only when it is confirmed that the vehicle is in a steady running state. In accordance with the abnormal fuel consumption rate calculated in the above, it is possible to reliably prevent the inappropriate update of the control map. When the control target value is read out based on the priority control map in which the priority corresponding to the fuel consumption is added to the control target value including the engine speed ESP as described above, The control target value that minimizes the fuel consumption rate can be quickly and appropriately read.

Further, as shown in the above embodiment, when it is confirmed that the vehicle is in an accelerating state or the like, the control target value read by the target value reading means 18 is corrected by the target value correcting means 22, In other words, the engine speed ESP
According to the configuration in which the control target value having the higher priority is selected within a range where the speed is not reduced, the driving force of the engine 2 becomes insufficient during acceleration due to the execution of the speed ratio control. Can be prevented. Therefore, while maintaining the fuel consumption rate in a good state by executing the gear ratio control in accordance with the above-mentioned priority order, it is possible to prevent the traveling feeling from deteriorating by securing the driving force of the engine 2 during the gear ratio control operation. The effect of being able to prevent such a situation can be achieved.

In the above embodiment, when it is confirmed that the vehicle is in a deceleration state, the target value correcting means 22
, And the control target value within the range of the current engine speed ESP or less is selected according to the priority order, thereby preventing the driving force of the engine 3 from unnecessarily increasing during deceleration. And the fuel consumption rate can be effectively reduced.

Also, based on the map shown in FIG. 6, the correction value n by the target value correction means 22 is changed according to the change state of the engine load, that is, the change rate (dTVO / dt) of the throttle opening TVO. According to the configuration described above, when the vehicle is in a rapid acceleration state, etc., the engine speed ESP is set to a higher value in advance in accordance with this, so that a more appropriate shift control suitable for the acceleration state is performed. By doing so, the driving feeling can be effectively improved.

In order to smoothly execute the gear ratio control during acceleration or the like, as shown in FIG. 8, for example, as shown in FIG.
Is desirably gradually increased to shift to the control target value B.

[0032]

As described above, the present invention is configured to sequentially update the control map stored in the map storage means according to the fuel consumption rate calculated by the fuel consumption rate calculation means when the engine is operating. Therefore, the control target value is always read based on the latest data, and the appropriate gear ratio control corresponding to the control target value can be executed. Therefore, the control map set to an appropriate state at the manufacturing stage changes according to changes over time, changes in engine characteristics due to changes in outside air conditions or changes in the type of gasoline used, or variations in engine performance due to mass production. It is possible to prevent the occurrence of a situation in which there is no match. Therefore, by reading the control target value that minimizes the fuel consumption rate from the control map, the gear ratio control of the continuously variable transmission can be executed in accordance with the running state of the vehicle, the operating state of the engine, and the like. There is an advantage.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a drive system of a vehicle having a shift control device for a continuously variable transmission according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a control unit of the shift control device.

FIG. 3 is a chart showing a control map.

FIG. 4 is a table showing a priority order map.

FIG. 5 is a flowchart showing a control operation of the shift control device.

FIG. 6 is a graph showing a relationship between a correction value and a throttle opening.

FIG. 7 is a flowchart showing a control map update routine.

FIG. 8 is a graph showing a control characteristic of a control target value.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 continuously variable transmission 2 engine 12 variable speed driving means 17 map storage means 18 target value reading means 19 fuel efficiency calculating means 20 map updating means 21 acceleration detecting means 22 target value correcting means

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16H 9/00 F16H 59/00-61/24

Claims (3)

(57) [Claims] 1. A target value reading means for reading a control target value based on a control map in which a control target value corresponding to an operation state of an engine is set, and a speed ratio of a continuously variable transmission according to the control target value. And a control map in which a control target value is set in advance using the operating state of the engine and the fuel consumption rate as parameters, and the operating state of the engine and the fuel consumption. Rate and
The control target value is set using
The target values are prioritized according to the fuel consumption rate.
Map storage means for storing a prioritized control map ; fuel consumption rate calculation means for obtaining a fuel consumption rate according to the operating state of the engine; and a control map stored in the map storage means according to the calculated value of the fuel consumption rate. And priority control
And a map updating means for updating the map .
Engine based on the operating state and the priority control map.
The highest priority number corresponding to the operating status of the
Select the control target value corresponding to this priority number
Is read out from the control map . An acceleration detecting means for detecting an acceleration state of the vehicle; and a control target value read by the target value reading means when the vehicle is detected to be in an accelerated state. the shift control device for a continuously variable transmission according to claim 1, characterized in that a target value correcting means for correcting the free range. 3. The control system according to claim 2, wherein the rate of change of the engine load is determined by the acceleration detecting means, and the correction range of the control target value is set in accordance with the rate of change of the engine load. Transmission control device for a step transmission.