JP2754932B2 - Transmission control device - Google Patents

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, and more particularly to a shift control device for a continuously variable transmission.

[0002]

2. Description of the Related Art As a structure used for a so-called stepless speed change mechanism, a belt is stretched between a pair of pulleys, and a groove width of a pulley on which the belt is hung is changed to change a driving side and a driven side. (Hereinafter referred to as CVT mechanism). One of the mechanisms for changing the groove width of the pulley is to displace a movable conical plate facing one fixed conical plate constituting the pulley in the axial direction by using a hydraulic mechanism. There is a structure to make it. In the above-described continuously variable transmission mechanism, the groove width in the pulley is set so as to obtain a transmission ratio capable of transmitting the engine-side torque. Uses a hydraulic control mechanism for displacing the movable conical plate of the pulley in the axial direction. An example of the shift control by the above-described hydraulic control mechanism is disclosed in Japanese Patent Application Laid-Open No. 62-53249.
And JP-A-62-26134. Among the structures described in the above-mentioned publications, according to the former, an engine torque is calculated based on each information on a throttle opening sensor and an engine speed, and the pulley is moved in accordance with the engine torque. The target line pressure in the hydraulic control mechanism for causing the conical plate to be displaced is set. According to the latter, the engine output information obtained on the engine control unit side is used for the hydraulic control described above. The information is used as information for setting the line pressure in the mechanism.

[0003]

As described above, the target line pressure in the hydraulic control mechanism of the CVT mechanism is set in accordance with the engine torque calculated based on the information of the throttle opening and the engine speed which are directly input. In the former structure, a measure is taken when information from the throttle opening sensor is not transmitted due to a disconnection of a signal line connected between the throttle opening sensor and the hydraulic control mechanism of the CVT mechanism. When the throttle opening information is not input, the line pressure is set in the hydraulic control mechanism of the CVT mechanism by regarding the throttle opening as being fully open. However, when the line pressure is set by such processing with only the throttle opening, the state in which the belt holding pressure by the movable cone plate of the pulley in the CVT mechanism is the maximum is obtained. Result in excessive load. Accordingly, the durability of the belt is degraded, or the speed ratio is set to a low speed state as the operation state when the throttle opening is at the maximum, so that noise and fuel consumption may be deteriorated. Further, in the latter structure, the engine output information obtained by the engine control unit is taken into the hydraulic control mechanism and used as information for setting the line pressure, a signal line is provided between the engine control unit and the hydraulic control mechanism. No measures are taken when information from the engine control unit is not transmitted due to a disconnection accident or the like, and in this case, there is a problem that the line pressure setting by the hydraulic control mechanism is not optimally performed.

In view of the above-mentioned problems in the conventional shift control device, the object of the present invention is to input control information relating to engine torque from an engine controller to a CVT mechanism and calculate engine torque based on the control information. A shift control device for setting the groove width of the pulley in accordance with the engine torque. If the control information relating to the engine torque is not input from the engine controller, etc. To obtain a shift control device that allows setting of a groove width from a gear ratio corresponding to an actual engine torque without setting, thereby preventing deterioration of belt durability, noise, or fuel consumption. It is in.

[0005]

In order to achieve this object, the present invention provides a drive pulley for inputting a drive force from an engine and the drive transmitted via a belt wound between the drive pulley and the drive pulley. A speed change control device for a continuously variable transmission that changes the winding diameter of the belt by changing the groove width with a driven pulley that outputs a force, and that performs engine output control based on a plurality of pieces of control information. Input control information on engine torque from the engine control device,
An actual engine torque calculating means for calculating an actual engine torque, a predicted acceleration calculating means for calculating a predicted acceleration of the vehicle from the actual engine torque, and an actual vehicle speed change rate calculating for inputting the actual vehicle speed and calculating a change rate of the actual vehicle speed Means, comparing the predicted acceleration with the actual vehicle speed change rate, and when the difference between the predicted change rate and the vehicle speed change rate is equal to or greater than a predetermined value, control information regarding the engine torque from the engine control device is transmitted. Abnormality detecting means for judging an abnormality, and a set engine torque calculation for directly inputting a throttle opening and an engine speed and extracting a set engine torque set in advance according to a relationship between the throttle opening and the engine speed. Means for controlling the gear ratio in accordance with the actual engine torque, and when the abnormality detecting means determines that there is an abnormality, It is characterized by having a shift control means for controlling the gear ratio in accordance with the constant engine torque.

[0006]

According to the speed change control device of the present invention, control information relating to engine torque is input from the engine control device, an actual engine torque is determined based on the control information, and a predicted acceleration of the vehicle is determined from the actual engine torque. On the other hand, the rate of change of the actual vehicle speed is determined from the actual vehicle speed, and when the difference between the actual vehicle speed change rate and the predicted acceleration is equal to or less than a predetermined value, that is, when the difference is normal, the shift control is performed in accordance with the actual engine torque. If it is equal to or greater than the value, it is determined that the control information input from the engine control device to the shift control device is abnormal, and the throttle relation and engine speed are determined in advance based on the throttle opening and the engine rotational speed that are manually input. A set engine torque set according to the relationship with the number of revolutions is extracted, and shift control is performed according to the set engine torque.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to FIGS. FIG. 1 is a block diagram for explaining a configuration for executing a shift control according to an embodiment of the present invention.

In this embodiment, a shift control device (hereinafter, referred to as a line control device) for setting and controlling a line pressure for setting a groove width of a pulley.
A CVT control device) 1 and an engine control device 2 connected thereto are used. That is, the engine control device 2 is constituted by a well-known engine controller, and an air flow sensor 2A required for setting combustion conditions.
Information from the intake air temperature sensor 2B and the intake pressure sensor 2C is input.

On the other hand, the CVT control device 1 has an input side to which the output side of the above-described engine control device 2 is connected, in addition to a throttle opening sensor 1A and an engine speed sensor (engine speed information) 1B. , A vehicle speed sensor 1C is directly connected. Throttle opening sensor 1 described above
A and the engine speed sensor 1B are used for calculating the engine torque in the CVT control device 1. The throttle opening sensor 1A and the engine speed sensor 1B are also connected to the input side of the engine control device 2. On the input side of the above-mentioned CVT control device 1, although not shown, an inhibitor switch interlocking with a select lever of an automatic transmission and a hydraulic sensor for detecting the pressure of a clutch control oil passage of a fluid coupling. Are connected, and
Although not shown, a pressure control valve 3 (see FIG. 2) for setting pressure to the above-described clutch control oil passage is connected to the output side, and an electromagnetic valve (not shown) is attached to the pressure control valve. The duty control for setting the groove width is performed.

In the above-described CVT control device 1, the following control is executed. That is, FIG.
2 shows the contents of data processing in the control device shown in FIG. 2. In the same figure, the CVT control device 1 sends the intake air amount (Q _A ), intake air temperature (T _A ), intake air pressure (P _A ),
The control information about the engine torque calculated by the engine speed (N _E ) is fetched, and the actual engine torque is calculated by the control information about the engine torque.
A predicted value (A) of the acceleration of the vehicle on the engine side is obtained from the actual engine torque and the speed ratio and the like under the same conditions regarding the vehicle speed, the engine speed and the running resistance. Is detected, the rate of change (dV / dt) at the actual vehicle speed is obtained.

Then, a difference between the above-mentioned predicted acceleration A and the rate of change of the actual vehicle speed (dV / dt) is determined. When the difference is equal to or greater than a predetermined value, the control information from the engine control device 2 indicates the CV.
It is determined that an abnormal situation mainly occurs when the input is not input to the T control device 1, and the throttle opening and the engine speed are directly input and set in advance from the relationship between the throttle opening and the engine speed. The set engine torque is used. That is, when an abnormal situation has occurred, information regarding the throttle opening and the engine speed is directly taken in, the clutch pressure is set based on the set engine torque described above, and the groove width setting based on the clutch pressure is performed. Line pressure is set. The predicted value of the vehicle acceleration used in the above-described determination is obtained on the assumption that the road surface gradient is 0%.

Since the present embodiment has the above structure,
The operation will be described with reference to the flowchart shown in FIG. In other words, the above-described information is taken into the CVT control device 1 and the engine control device 2 so that the engine control device 2 sets the fuel injection conditions and controls the driving of the fuel injection device 4 while performing the control. ,
In the CVT control device 1, control information on the engine torque is taken in from the engine control device 2 to calculate the engine torque. The predicted value A of the vehicle acceleration is obtained from the engine torque and the gear ratio, while the vehicle speed sensor 1
The change rate (dV / dt) of the actual vehicle speed is obtained from the information from C. The absolute value of the difference between the predicted value A of the acceleration and the rate of change of the actual vehicle speed (dV / dt) is a predetermined value (k).
It is determined whether the control information from the engine control device 2 is abnormal by determining whether or not it is larger than the control information. When the pressure is equal to or less than the predetermined value (k), that is, when the engine pressure is normal, the line pressure for setting the groove width by the CVT controller 1 is set based on the actual engine torque obtained from the control information on the engine torque from the engine controller 2. Desired. On the other hand, if it is equal to or more than the predetermined value (k),
The control information regarding the engine torque from the engine control device 2 is determined to be abnormal, and the CVT control device is determined based on the set engine torque (TE ') obtained based on the directly input throttle opening and engine speed. The line pressure for setting the groove width according to 1 is determined. The determination of the magnitude relationship between the difference between the predicted value of the acceleration with respect to the predetermined value and the rate of change of the actual vehicle speed is not limited to being completed only once, but may be performed, for example, a plurality of times within a predetermined time,
Alternatively, by determining the tendency of the difference, the probability may be obtained and the determination may be made in a state where the determination error is eliminated.

According to this embodiment, whether the control information on the engine torque from the engine control device is abnormal is calculated based on the control information on the engine torque input from the engine control device, and
The CVT control unit can determine the vehicle speed and the gear ratio based on the engine torque obtained from the throttle opening and the engine rotation speed that are directly input in the event of an abnormality, so that the engine control unit and the CVT control unit can be used. For example, it is not necessary to provide a special sensor for detecting the engine torque for setting the groove width when a failure occurs in the information transmission path between the two.

[0014]

As described above, according to the shift control device of the present invention,
When the control information on the engine torque is taken in from the engine control device as the information of the groove width setting of the pulley, and the target value of the line pressure for setting the groove width is set by the control information on the engine torque, the information from the engine control device may It is possible to automatically determine that the control information relating to the engine torque is abnormal, and if it is abnormal, based on the set engine torque obtained from the directly input throttle opening and engine speed, The line pressure for setting the groove width of the pulley can be set. Therefore, even when the information transmission path from the engine control device to the CVT control device fails, the groove width setting of the pulley can be controlled under substantially the same conditions as usual, in other words, deemed control is performed. As a result, it is possible to prevent an abnormal load from being applied to the belt, and to suppress an abnormal increase in noise and fuel consumption.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration for executing a shift control according to an embodiment of the present invention.

FIG. 2 is a block diagram for explaining data processing of the CVT control device shown in FIG.

FIG. 3 is a flowchart for explaining the operation of the CVT control device shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 CVT control device 2 Engine control device 1A Throttle opening sensor 1B Engine rotation speed sensor 1C Vehicle speed sensor

Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16H 59:48 63:06

Claims (1)

(57) [Claims] The groove width of a driving pulley for inputting a driving force from an engine and a driven pulley for outputting the driving force transmitted via a belt wound between the driving pulley and the driven pulley are changed. A shift control device for a continuously variable transmission that shifts by changing the winding diameter of a belt, wherein control information about engine torque is input from an engine control device that controls output of an engine based on a plurality of pieces of control information. An actual engine torque calculating means for calculating a torque; a predicted acceleration calculating means for calculating a predicted acceleration of the vehicle from the actual engine torque; an actual vehicle speed change rate calculating means for inputting the actual vehicle speed and calculating a change rate of the actual vehicle speed; Comparing the predicted acceleration with the actual vehicle speed change rate, if the difference between the predicted change rate and the vehicle speed change rate is equal to or greater than a predetermined value, Abnormality detection means for determining that the control information relating to the engine torque is abnormal; a throttle opening and an engine speed directly input to set engine torque which is set in advance according to a relationship between the throttle opening and the engine speed; Setting engine torque calculating means for extracting the engine speed; controlling the gear ratio in accordance with the actual engine torque; and controlling the gear ratio in accordance with the set engine torque when the abnormality detecting means determines that the gear ratio is abnormal. A shift control device comprising: