JPH111135A - Driving force control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a driving force control device that can independently set target driving force determining operability of a vehicle, and a target change gear ratio having large influence on fuel consumption and can correct target engine torque according to the operating state of continuously variable transmission discontinuous mechanism such as a start clutch and a torque converter by improving on technique of determining the target change gear ratio and target engine torque. SOLUTION: A target driving force computing part A computes target driving force on the basis of the accelerator operating quantity and vehicle speed, and a target change gear ratio computing part B computes a target change gear radio on the basis of the accelerator operating quantity and vehicle speed. A target engine torque computing part C computes target engine torque on the basis of the inputted target driving force and change gear ratio, engine speed and input side rotating speed of a continuously variable transmission, and a target throttle opening computing part D computes target throttle opening on the basis of the target engine torque and engine speed. The continuously variable transmission is driven so that the change gear ratio becomes the target change gear ratio, and an electrically controlled throttle is driven so that throttle opening becomes the target throttle opening.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force control device for a vehicle, and more particularly to a vehicle having a continuously variable transmission interposed between an engine and a drive shaft and capable of continuously adjusting a speed ratio. And a driving force control device.

[0002]

2. Description of the Related Art A continuously variable transmission (CVT) of this type includes two pulleys whose effective diameters can be continuously changed and a belt wound between the two pulleys. The line pressure (the fluid pressure on the driven side) is supplied to the actuator of the other pulley, and the line pressure is adjusted to a predetermined pressure via a speed change control valve (flow control valve) using the line pressure as an original pressure for speed change control. The drive-side fluid pressure is supplied to perform a continuously variable transmission.

[0003] As a driving force control device for a vehicle provided with such a continuously variable transmission (CVT), the following is conventionally known (see Japanese Patent Application Laid-Open No. 62-110536). In this technology, a target driving force is calculated by a target driving force calculation unit mainly in relation to an accelerator operation amount and a vehicle speed.
A target gear ratio of the continuously variable transmission is determined by a target gear ratio calculation unit in relation to the target driving force and the vehicle speed, and the actual gear ratio of the continuously variable transmission is feedback-controlled to the target gear ratio, while the gear ratio is changed. The target engine torque in relation to the ratio and the target driving force,
A target value of a means (for example, a throttle actuator) for changing the engine torque in relation to the target engine torque and the actual engine rotational speed, for example, a target throttle opening degree, which is obtained by a target engine torque calculation unit, The feedback calculation is performed by a means (for example, a throttle actuator) that is obtained by the opening calculation unit and can change the engine torque to the target throttle opening (see FIG. 6).

[0004]

However, in such a conventional driving force control device, as described above, the target speed ratio of the continuously variable transmission is searched from the target driving force and the vehicle speed. Therefore, there are the following problems.
That is, as described above, if the map of the target driving force for obtaining the target driving force in relation to the accelerator operation amount and the vehicle speed is changed for tuning the drivability of the vehicle, the target driving force and the vehicle speed are changed. The target gear ratio retrieved from the above also changes.

That is, the target driving force that determines the drivability of the vehicle and the target gear ratio that greatly affects fuel efficiency cannot be set independently, and it is difficult to achieve both improved drivability and improved fuel efficiency of the vehicle. Further, since the conventional technology is configured to obtain the target engine torque in relation to the gear ratio and the target driving force, an electromagnetic clutch or a torque converter as a starting clutch for connecting / disconnecting the engine driving force to / from the continuously variable transmission is provided. There is also a problem that the target engine torque cannot be corrected according to the operating state of the connection / disconnection mechanism (starting mechanism), and the control accuracy of the driving force when the operation state of the connection / disconnection mechanism is disconnected.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and a target driving force for determining drivability of a vehicle by improving a method of determining a target speed ratio and a target engine torque. And the target gear ratio, which greatly affects fuel efficiency, can be set independently, and the target engine torque can be corrected according to the operating state of the continuously variable transmission connection / disconnection mechanism such as the starting clutch and torque converter. It is an object to provide a driving force control device for a vehicle.

[0007]

Therefore, according to the present invention, as shown in FIG. 1, an engine torque varying means for varying an engine torque without relating to an accelerator operation, an engine and a vehicle drive shaft are provided. A continuously variable transmission that is interposed between and that continuously changes the speed ratio, an accelerator operation amount detection unit, a vehicle speed detection unit, an engine rotation speed detection unit,
Speed ratio calculating means for calculating a speed ratio of the continuously variable transmission,
A target for calculating a target driving force based on an input-side rotational speed detecting means for detecting an input-side rotational speed of the continuously variable transmission, and detection signals output from the accelerator operation amount detecting means and the vehicle speed detecting means; Driving force calculating means; target gear ratio calculating means for calculating a target gear ratio of the continuously variable transmission based on detection signals output from the accelerator operation amount detecting means and vehicle speed detecting means; Based on signals output from the force calculating means, the speed ratio calculating means, the engine rotational speed detecting means and the input side rotational speed detecting means,
A target engine torque calculating means for calculating a target engine torque; a target value calculating means for calculating a target value of the engine torque varying means based on the target engine torque and the engine rotation speed; and An engine torque variable means control means for controlling to a target value, and a continuously variable transmission control means for changing the speed ratio of the continuously variable transmission and performing feedback control of the speed ratio to the target speed ratio. A driving force control device for a vehicle, comprising:

The invention according to claim 2 is characterized in that the engine torque varying means is a throttle actuator, and the target of the target value is a throttle opening.
According to a third aspect of the invention, the continuously variable transmission includes two pulleys whose effective diameters can be continuously changed, and a belt wound between the two pulleys, and one of the pulleys is driven by an actuator. A configuration in which the side fluid pressure is supplied, and the drive fluid pressure adjusted to a predetermined pressure with the driven fluid pressure as the original pressure is supplied to the actuator of the other pulley for speed change control, thereby performing a continuously variable transmission. It is characterized by.

The invention according to claim 4 is characterized in that a connection / disconnection mechanism for connecting / disconnecting the continuously variable transmission is interposed between the continuously variable transmission and the engine. The invention according to claim 5 is
The connection / disconnection mechanism is a starting clutch.

According to a sixth aspect of the present invention, the disconnecting and connecting mechanism comprises:
It is a torque converter. In the invention according to claim 7, the target engine torque calculating means calculates a target engine torque based on a speed ratio of the connection / disconnection mechanism, a target driving force, and a gear ratio obtained from the engine rotation speed and the input-side rotation speed. It is characterized by doing.

The invention according to claim 8 is characterized in that the speed ratio calculating means calculates a speed ratio based on an input side rotation speed and an output side rotation speed of the continuously variable transmission. According to a ninth aspect of the present invention, there is provided a driving force control device for a vehicle including a continuously variable transmission interposed between an engine and a drive shaft and capable of continuously adjusting a speed ratio. , A target driving force of the continuously variable transmission is calculated based on the accelerator operation amount and the vehicle speed, while the target driving force, the speed ratio, the engine rotation speed, and the target driving force are calculated. A target engine torque is calculated based on the input-side rotational speed of the step transmission.

The operation of the present invention will be described. In the invention according to claim 1, the target driving force calculating means includes:
The accelerator operation amount and the vehicle speed are input, and the target driving force is calculated based on these. The accelerator operation amount and the vehicle speed are input to the target gear ratio calculation unit, and based on these,
Calculate the target gear ratio.

The target engine torque calculating means calculates a target engine torque based on the input target driving force, speed ratio, engine speed, and input side speed of the continuously variable transmission. The target throttle opening calculator receives the target engine torque and the engine rotation speed, and calculates the target throttle opening based on these.

Then, the continuously variable transmission is driven such that the speed ratio becomes the target speed ratio. Further, the engine torque varying means is driven so as to have a target value. As described above, the target driving force is calculated based on the accelerator operation amount and the vehicle speed, and the target gear ratio of the continuously variable transmission is calculated based on the accelerator operation amount and the vehicle speed. Changes in the target driving force map for obtaining the target driving force in relation to the operation amount and the vehicle speed, tuning for vehicle drivability, and fuel efficiency in the target speed ratio map for the continuously variable transmission And tuning changes can be made independently. Further, the target engine torque can be corrected in accordance with the operating state of a connection / disconnection mechanism (starting mechanism) such as a starting clutch or a torque converter for connecting / disconnecting the engine driving force to / from the continuously variable transmission.

According to the second aspect of the present invention, the engine torque is varied by varying the throttle opening degree by the throttle actuator.
It is driven to reach the target throttle opening. Claim 3
In the continuously variable transmission, the driven fluid pressure is supplied to the actuator of one of the pulleys, and the actuator of the other pulley uses the driven fluid pressure as the original pressure for the speed change control. The continuously variable transmission is performed by supplying the drive-side fluid pressure adjusted to.

In the invention according to claims 4 to 6, the continuously variable transmission and the engine are connected and disconnected by a connection / disconnection mechanism (starting clutch, torque converter), and the connection / disconnection mechanism functions as a starting mechanism. In the invention according to claim 7, the target engine torque is calculated based on the speed ratio of the connection / disconnection mechanism, the target driving force, and the gear ratio, which are obtained from the engine rotation speed and the input-side rotation speed.

As described above, the target engine torque is calculated based on the speed ratio of the connection / disconnection mechanism obtained from the engine rotation speed and the input-side rotation speed, the target driving force, and the speed ratio, and thus the speed of the connection / disconnection mechanism is reduced. According to the ratio, it is possible to correct the driving force when the operation state of the connection / disconnection mechanism is the disconnection state. In the invention according to claim 8, the speed ratio is calculated based on the input side rotation speed and the output side rotation speed of the continuously variable transmission.

According to the ninth aspect of the present invention, a target driving force is calculated based on the accelerator operation amount and the vehicle speed, and a target gear ratio of the continuously variable transmission is calculated based on the accelerator operation amount and the vehicle speed. As a result, the target driving force map for obtaining the target driving force in relation to the accelerator operation amount and the vehicle speed is changed for tuning the drivability of the vehicle and the target speed ratio of the continuously variable transmission. The map can be changed independently for fuel efficiency tuning.
Also, a connection / disconnection mechanism (starting mechanism) such as a starting clutch or torque converter that connects / disconnects the engine driving force to / from the continuously variable transmission
The target engine torque can be corrected in accordance with the operation state of.

[0019]

According to the first and ninth aspects of the present invention, the target driving force that determines the drivability of the vehicle and the target speed ratio that greatly affects fuel efficiency can be set independently, and the drivability of the vehicle can be improved. The target engine torque is corrected according to the operating state of the starting / closing mechanism (starting mechanism) such as a starting clutch or torque converter that connects / disconnects the engine driving force to / from the continuously variable transmission, while improving fuel economy. It is possible to improve not only the operation state of the connection / disconnection mechanism but also the control accuracy of the driving force in the disconnection state.

According to the second aspect of the invention, the engine torque can be varied by varying the throttle opening by the throttle actuator. According to the third aspect of the present invention, the continuously variable transmission performs the continuously variable transmission by supplying the driven fluid pressure to the actuator of one pulley and the driving fluid pressure to the actuator of the other pulley. It can be carried out.

According to the inventions according to the fourth to sixth aspects, the connection and disconnection between the continuously variable transmission and the engine can be easily performed, and starting can be facilitated. According to the seventh aspect of the present invention, the connection and disconnection is configured by calculating the target engine torque based on the speed ratio of the connection and disconnection mechanism obtained from the engine rotation speed and the input side rotation speed, the target driving force, and the gear ratio. According to the speed ratio of the mechanism, it is possible to correct the driving force when the operating state of the connection / disconnection mechanism is disconnected, and use a case using a starting clutch or a torque converter as the connection / disconnection mechanism of the continuously variable transmission. The driving force can be easily corrected in accordance with the slip ratio in accordance with the case, and the control accuracy of the driving force can be improved by a simple method.

According to the invention according to claim 8, the gear ratio is
It can be easily obtained based on the input side rotation speed and the output side rotation speed of the continuously variable transmission.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a configuration diagram of an engine control system to which one embodiment of the present invention is applied. In this figure, an engine control system is for electronically controlling an engine 1. A control unit 2 includes an intake air amount measured by an air flow meter 3 and a crank angle sensor 4 as engine rotation speed detecting means.
A fuel amount corresponding to the intake air amount and an ignition timing corresponding to the engine load and the engine rotation speed are calculated based on the engine rotation speed and the phase of the engine rotation measured by the ECU, and an injector is provided to supply the fuel amount. 5 and drive the ignition plug 6 according to the ignition timing.
Controls the ignition control mechanism to perform ignition.

The intake system is provided with an electronically controlled throttle 7 capable of electronically controlling the throttle opening, thereby controlling the throttle opening irrespective of the accelerator operation amount.
Controls the amount of intake air. Note that the throttle actuator 8 corresponds to an engine torque varying unit that varies the engine torque without relating to the accelerator operation. FIG. 3 shows a continuously variable transmission to which one embodiment of the present invention is applied, that is, a CV.
It is a block diagram of the system of T9.

In FIG. 1, the CVT 9 includes two pulleys 10 and 11 whose effective diameters can be continuously changed, and a belt 12 wound between the pulleys 10 and 11, and one of the pulleys (secondary pulley). The secondary hydraulic pressure obtained by correcting the line pressure (the fluid pressure on the driven side) by the hydraulic control valve 13 is supplied to the actuator 11A of the eleventh, and the line pressure for the speed change control is supplied to the actuator 10A of the other pulley (primary pulley) 10. The gear pressure is adjusted to a predetermined pressure via the hydraulic pressure control valve 13 as the original pressure, that is, the primary hydraulic pressure is supplied to perform the continuously variable transmission.

The control unit 2 controls the connection and disconnection of the engine driving force by an electromagnetic clutch 14 as a connection / disconnection mechanism of the CVT 9 and an input measured by an input shaft rotation speed sensor 15 as input side rotation speed detection means of the CVT 9. The primary hydraulic pressure and the secondary hydraulic pressure are set so that the gear ratio calculated based on the shaft rotation speed and the output shaft rotation speed measured by the output shaft rotation speed sensor 16 as the output side rotation speed detection means becomes the target gear ratio. Control.

A configuration using a torque converter as the connection / disconnection mechanism of the CVT 9 is also conceivable. Here, FIG. 4 is a functional configuration diagram of each arithmetic unit provided in the control unit 2 which controls the function of the vehicle driving force control device of the present invention.
The calculation unit in the vehicle driving force control device includes a target driving force calculation unit A, a target gear ratio calculation unit B, a target engine torque calculation unit C, and a target throttle opening calculation unit D.

The target driving force calculating section A outputs an accelerator operation amount APS output from an accelerator sensor 17 as an accelerator operation amount detecting means and a vehicle speed sensor (output shaft rotational speed sensor) 16 as a vehicle speed detecting means. Vehicle speed VS
P is input, and based on these, the target driving force tTd
Is calculated. The target gear ratio calculator B receives the accelerator operation amount APS output from the accelerator sensor 17 and the vehicle speed VSP output from the vehicle speed sensor 16, and calculates the target gear ratio tRoi based on these.

The speed ratio Roi is determined by the ratio (Ni / N) of the output shaft rotation speed No of the CVT 9 and the input shaft rotation speed Ni.
o). The target engine torque calculation unit C calculates a target engine torque tTe based on the input target driving force tTd, the speed ratio Roi, the engine rotation speed Ne, and the input rotation speed Ni of the CVT 9. In the present embodiment, the speed ratio Rie (Ni / N) of the electromagnetic clutch 14 or the torque converter is determined based on the input engine rotation speed Ne and the input-side rotation speed Ni.
e), and calculates a target engine torque tTe based on the input target driving force tTd and the speed ratio Roi.

Here, the target engine torque tTe is t
Te = tTd / predetermined value × Roi / Rtrq. The predetermined value is a constant for converting a driving force into a CVT output shaft torque, and Rtrq is a starting clutch (electromagnetic clutch) 1 as a disconnecting / connecting mechanism (starting mechanism) of the CVT 9.
4 or the torque ratio of the torque converter, and is associated with the speed ratio Rie, respectively, and changes according to the speed ratio as shown in FIG. 5A (for the starting clutch) and FIG. 5B (for the torque converter). .

The target throttle opening calculating section D receives the target engine torque tTe and the engine rotational speed Ne, and calculates the target throttle opening tTPS based on these. Then, the CVT 9 is driven by the control unit 2 so that the speed ratio Roi becomes the target speed ratio tRoi.

The electronically controlled throttle 7 is driven by the control unit 2 so that the throttle opening TPS becomes the target throttle opening tTPS. Here, the target driving force calculation unit A corresponds to a target driving force calculation unit of the present invention that calculates a target driving force based on detection signals output from the accelerator operation amount detection unit and the vehicle speed detection unit.

The target gear ratio calculator B calculates the target gear ratio of the continuously variable transmission based on the detection signals output from the accelerator operation amount detecting means and the vehicle speed detecting means. It corresponds to a calculating means. The present invention calculates the target engine torque based on signals output from the target driving force calculating means, the gear ratio calculating means, the engine rotational speed detecting means, and the input side rotational speed detecting means. Corresponds to the target engine torque calculating means.

The target throttle opening calculating section D corresponds to a target value calculating means of the present invention for calculating a target value of the engine torque varying means based on the target engine torque and the engine speed. In the vehicle driving force control device described above, the target driving force is calculated based on the accelerator operation amount and the vehicle speed, and the target speed ratio of the CVT 9 is calculated based on the accelerator operation amount and the vehicle speed. Therefore, the map for the target driving force for obtaining the target driving force in relation to the accelerator operation amount and the vehicle speed is changed for tuning the drivability of the vehicle, and the map of the target speed ratio of the CVT 9 is obtained. However, changes for tuning of fuel efficiency can be made independently.

As a result, the target driving force that determines the drivability of the vehicle and the target gear ratio that greatly affects fuel efficiency can be set independently, and it is easy to achieve both improved drivability and improved fuel efficiency of the vehicle. Further, since the target engine torque is calculated based on the target driving force, the gear ratio, the engine rotation speed, and the input-side rotation speed of the CVT 9, the engine driving force is connected to and disconnected from the continuously variable transmission. The target engine torque can be corrected according to the operating state of the starting / closing mechanism (starting mechanism) such as the starting clutch (electromagnetic clutch 16) and the torque converter. Control accuracy of the driving force can be improved.

In particular, according to the present embodiment, the target engine torque is calculated based on the speed ratio of the electromagnetic clutch or the torque converter, the target driving force, and the speed ratio obtained from the engine speed and the input-side speed. Therefore, it is possible to correct the driving force when the operating state of the connection / disconnection mechanism is in the disconnected state according to the speed ratio of the electromagnetic clutch or the torque converter. That is, it is possible to easily correct the driving force according to the slip ratio in a case where a starting clutch or a case where a torque converter is used as the connection / disconnection mechanism of the CVT 9, and the driving force can be corrected by a simple method. Control accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to a claim of a driving force control device for a vehicle according to the present invention.

FIG. 2 is a configuration diagram of an engine control system to which an embodiment of the present invention is applied;

FIG. 3 is a configuration diagram of a CVT system to which the above embodiment is applied;

FIG. 4 is a functional configuration diagram of each arithmetic unit provided in a control unit that functions as a vehicle driving force control device according to the present invention;

FIGS. 5A and 5B are characteristic diagrams showing a relationship between a torque ratio and a speed ratio of a starting clutch or a torque converter as a connecting / disconnecting mechanism (starting mechanism) of the CVT.

FIG. 6 is a functional configuration diagram of each calculation unit of the vehicle driving force control device according to the related art.

[Explanation of symbols]

 Reference Signs List 1 engine 2 control unit 4 crank angle sensor 7 electronically controlled throttle 8 throttle actuator 9 CVT A target driving force calculation unit B target gear ratio calculation unit C target engine torque calculation unit D target throttle opening calculation unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16H 59:42 59:70 63:06

Claims (9)

[Claims] An engine torque varying means for varying an engine torque without being related to an accelerator operation; a continuously variable transmission interposed between the engine and a vehicle drive shaft for continuously changing a gear ratio; Accelerator operation amount detecting means, vehicle speed detecting means, engine rotational speed detecting means, speed ratio calculating means for calculating a speed ratio of the continuously variable transmission, and input for detecting an input-side rotational speed of the continuously variable transmission. Side rotational speed detecting means, target driving force calculating means for calculating a target driving force based on detection signals output from the accelerator operation amount detecting means and vehicle speed detecting means, the accelerator operation amount detecting means and vehicle speed Target speed ratio calculating means for calculating a target speed ratio of the continuously variable transmission based on a detection signal output from the detecting means; target driving force calculating means; speed ratio calculating means; Target engine torque calculation means for calculating a target engine torque based on signals output from the rotation speed detection means and the input side rotation speed detection means; and an engine torque variable based on the target engine torque and the engine rotation speed. Target value calculation means for calculating a target value of the means; engine torque variable means control means for controlling the engine torque variable means to the target value; and changing the gear ratio of the continuously variable transmission to change the gear ratio. A driving force control device for a vehicle, comprising: a continuously variable transmission control unit that performs feedback control to a target gear ratio. 2. A vehicle driving force control apparatus according to claim 1, wherein said engine torque varying means is a throttle actuator, and said target value is a throttle opening. 3. The continuously variable transmission includes two pulleys whose effective diameters can be continuously changed, and a belt wound between the two pulleys. Is supplied to the actuator of the other pulley and the drive-side fluid pressure adjusted to a predetermined pressure with the driven-side fluid pressure as the original pressure for speed change control, thereby performing a continuously variable transmission. The driving force control device for a vehicle according to claim 1 or 2, wherein 4. A connecting / disconnecting mechanism for connecting / disconnecting a continuously variable transmission between said continuously variable transmission and an engine. A driving force control device for a vehicle according to claim 1. 5. A driving force control device for a vehicle according to claim 4, wherein said connection / disconnection mechanism is a starting clutch. 6. A driving force control apparatus for a vehicle according to claim 4, wherein said connection / disconnection mechanism is a torque converter. 7. The target engine torque calculating means calculates a target engine torque based on a speed ratio of a connecting / disconnecting mechanism, a target driving force, and a speed ratio obtained from the engine speed and the input-side speed. The driving force control device for a vehicle according to any one of claims 4 to 6, wherein: 8. The speed ratio calculating means calculates a speed ratio based on an input side rotation speed and an output side rotation speed of the continuously variable transmission.
4. A driving force control device for a vehicle according to claim 1. 9. A driving force control device for a vehicle having a continuously variable transmission interposed between an engine and a drive shaft and capable of continuously adjusting a speed ratio, the method being based on an accelerator operation amount and a vehicle speed. Calculating the target driving force and calculating the target gear ratio of the continuously variable transmission based on the accelerator operation amount and the vehicle speed, while calculating the target driving force, the gear ratio, the engine rotational speed and the continuously variable transmission. A driving force control device for a vehicle, wherein a target engine torque is calculated based on the input-side rotational speed of the vehicle.