JP2007292279A - Drive control device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance fuel consumption and drivability in a drive control device of a vehicle containing a torque-controlled CVT. <P>SOLUTION: An operator demand converter 42 converts operator demand into variable state of desired transmission input torque T<SB>TRN, T</SB>and desired engine rotating velocity ω<SB>e, T</SB>which can provide an engine with maximum efficiency based on accelerator manipulated variable θ and vehicle speed V. The calculated desired transmission input torque T<SB>TRN, T</SB>and desired engine rotating velocity ω<SB>e, T</SB>are output to an IVT control unit 43 which controls the CVT 6 by torque. In addition, the desired engine rotating velocity ω<SB>e, T</SB>calculated is output to an engine control unit 44 which controls the engine by torque. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle drive control apparatus that controls CVT and engine output.

In a vehicle, a driver operates an accelerator pedal to request engine power. If the driver feels that the acceleration is insufficient, the driver will further depress the accelerator pedal.
In the control system of Patent Document 1, both energy input to the engine and reaction torque in the variator are adjusted based on an engine map stored in advance.
JP 7-505699 A

However, higher performance is desired in terms of both improved fuel efficiency and improved drivability.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle drive control device that can achieve both fuel efficiency and drivability.

  In order to solve the above-described problem, a torque-controlled continuously variable transmission mechanism (hereinafter referred to as CVT) capable of changing the gear ratio steplessly, an accelerator operation amount detecting means for detecting an accelerator operation amount, and a vehicle speed Vehicle speed detecting means for detecting, and a control unit for controlling the operation of the CVT and the engine. The control unit includes a driver request conversion unit for obtaining a state quantity for realizing a driving state of the vehicle requested by the driver. The driver request conversion unit includes a target engine for giving maximum efficiency to the engine as the state quantity based on the accelerator operation amount detected by the accelerator operation amount detection means and the vehicle speed detected by the vehicle speed detection means. The rotational speed and the target transmission input torque are calculated (claim 1).

  In the present invention, a request that the driver requests from the vehicle via the accelerator pedal is converted into a state quantity of target engine speed and target transmission input torque that can give the engine maximum efficiency. As a result, the engine can be operated at the maximum efficiency as much as possible without impairing the acceleration performance of the vehicle according to the driver's request. As a result, in a vehicle equipped with a torque control type CVT, both fuel efficiency and drivability can be achieved.

  In addition, the present invention provides a torque-controlled continuously variable transmission mechanism (hereinafter referred to as CVT) capable of changing a transmission gear ratio steplessly and a planetary gear mechanism interposed between an input shaft and an output shaft of the CVT. And a power circulation mode clutch coupled when realizing a power circulation mode for transmitting power in a speed ratio range including infinite gear ratio, and a direct connection mode for transmitting power only by CVT. An infinitely variable transmission continuously variable transmission (hereinafter referred to as IVT) including a direct coupling mode clutch, an accelerator operation amount detection means for detecting an accelerator operation amount, a vehicle speed detection means for detecting a vehicle speed, an IVT and an engine A control unit that controls the operation, and the control unit includes a driver request conversion unit that obtains a state quantity for realizing a driving state of the vehicle requested by the driver, and the driver request conversion unit Based on the accelerator operation amount detected by the accelerator operation amount detection means and the vehicle speed detected by the vehicle speed detection means, the target engine rotation speed and the target transmission input torque for giving the engine maximum efficiency are calculated as the state quantities. (Claim 2).

  In the present invention, a request that the driver requests from the vehicle via the accelerator pedal is converted into a state quantity of target engine speed and target transmission input torque that can give the engine maximum efficiency. As a result, the engine can be operated at the maximum efficiency as much as possible without impairing the acceleration performance of the vehicle according to the driver's request. As a result, in a vehicle having an IVT including a torque control type CVT, both fuel efficiency and drivability can be achieved.

  The driver request conversion unit includes a target vehicle speed calculation unit that calculates a target vehicle speed based on the detected accelerator operation amount and the detected vehicle speed, a target vehicle speed calculated by the target vehicle speed calculation unit, and a detected vehicle speed. A target vehicle speed correction unit that corrects the target vehicle speed based on the comparison of the target vehicle speed to obtain a corrected target vehicle speed, and a state quantity calculation unit that calculates the target engine rotational speed and the target transmission input torque based on the corrected target vehicle speed. There is a case (Claim 3). In this case, the engine power can be artificially boosted by correcting the target vehicle speed based on a comparison between the target vehicle speed and the actual vehicle speed. Since the target vehicle speed is corrected by comparing with the actual vehicle speed, the capacity of the control loop can be reduced.

  Specifically, the target vehicle speed correction unit adds a correction amount obtained by multiplying the target vehicle speed calculated by the target vehicle speed calculation unit and the deviation of the detected vehicle speed by a predetermined gain to the target vehicle speed, thereby correcting the target vehicle speed. A target vehicle speed may be obtained (claim 4). In this case, since the deviation of the target vehicle speed and the actual vehicle speed and a single gain are used, it is easy to tune the transient characteristics of the engine power change. Also, the control loop is simple and inexpensive. In other words, the kick down function can be provided at a low cost.

  The state quantity calculation unit includes a target engine performance calculation unit that calculates a target engine rotation speed and a target engine torque for giving maximum efficiency to the engine based on an engine output corresponding to the corrected target vehicle speed, and a target engine performance calculation unit And a target transmission input torque calculation unit that calculates a target transmission input torque based on the target engine rotation speed and the target engine torque calculated by (5). In this case, the target value of engine power (target engine speed and target engine torque) boosted according to the driver's request is a characteristic curve (maximum efficiency) for obtaining maximum efficiency in the relationship between engine speed and engine torque. It is calculated according to a curve / PEC (peak efficiency curve). As a result, it is effective to improve fuel efficiency without impairing acceleration.

  The control unit includes a control unit for controlling the transmission torque of the CVT, and the target transmission input torque calculated by the target transmission input torque calculation unit is output to the control unit for controlling the transmission torque of the CVT. (Claim 6). The control unit includes an engine control unit for controlling engine torque, and the target engine speed calculated by the target engine performance calculation unit may be output to the engine control unit. ). By controlling the engine load torque via the torque control type CVT 6 and adding this control to the engine control, optimal control can be performed. It is particularly suitable when the CVT includes a full toroidal CVT.

Preferred embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram showing a schematic configuration of a vehicle drive control device according to an embodiment of the present invention. Referring to FIG. 1, an infinitely variable transmission continuously variable transmission 1 (hereinafter referred to as IVT 1) includes an IVT input shaft 5 connected to an output shaft 3 of an engine 2 via a torsional damper 4, and a full toroidal type. CVT6 which consists of a continuously variable transmission, the planetary gear mechanism 7, and the IVT output shaft 8 provided in parallel with the IVT input shaft 5 and connected with the driving wheel are provided. The CVT 6 is a so-called torque control type CVT.

The present embodiment will be described in accordance with a drive control device for a vehicle having IVT 1, but the present invention can be applied to any drive control device for a vehicle having a torque control type CVT.
The CVT 4 includes a CVT input shaft 9 provided coaxially with the IVT input shaft 5 and a hollow CVT output shaft 10 through which the CVT input shaft 9 is inserted. A pair of input disks 11 and 12 are provided on the CVT input shaft 9 so as to be integrally rotatable. These input discs 11 and 12 are arranged back to back and each form a toroidal lace. The CVT output shaft 10 is provided with a pair of output disks 13 and 14 each having a toroidal race respectively opposed to the toroidal race of the pair of input disks 11 and 12 so as to be integrally rotatable.

  Between the toroidal races of the input disks 11 and 12 and the output disks 13 and 14, rollers 15 and 16 for transmitting torque between the disks 11 and 13; Torque is transmitted from the input disk 11 to the output disk 13 via the roller 15, and torque is transmitted from the input disk 12 to the output disk 14 via the roller 16. Each roller 15, 16 is supported by a carriage 17. Although schematically shown in FIG. 1, actually, as shown in FIG. 2, the axis of the carriage 17 extends in a direction perpendicular to the rotation axis of the roller 16 and forms a predetermined caster angle β. Yes. The same applies to the roller 15 and the carriage 17 that supports it.

A terminal load is applied to both the disks 11, 13; 12, 14 by the oil pressure of the oil chamber 18. On the other hand, the rollers 15 and 16 are pressed against both the disks 11 and 13 and 12 and 14 by receiving a biasing force due to the pressure difference between the first and second oil chambers 20 and 21 of the hydraulic cylinder 19 via the carriage 17. It has been.
The rollers 15 and 16 supported by the carriage 17 cancel the imbalance between the reaction force generated in the carriage 17 by transmitting torque and the torque necessary to drive the output disks 13 and 14. The rotation axes of the rollers 15 and 16 are inclined so as to produce a swing angle. As a result, the postures of the rollers 15 and 16 change, and the speed ratio between the disks 11 and 13 and 12 and 14 changes continuously.

The planetary gear mechanism 7 includes a sun gear 22, a plurality of planetary gears 24 supported by the carrier 23, and a ring gear 25 having internal teeth that mesh with the planetary gear 24.
The planetary gear mechanism 7 is interposed between the CVT input shaft 9 and the CVT output shaft 10. Specifically, first, the ring gear 25 is connected to the IVT output shaft 8 so as to be integrally rotatable.
The rotation of the CVT input shaft 9 is transmitted to the carrier 23 through the gear train 26 and the connected power circulation mode clutch 27 (also referred to as a low clutch). The gear train 26 includes a gear 26 a that is connected to the CVT input shaft 9 so as to be integrally rotatable, and a gear 26 b that meshes with the gear 26 a and is rotatably supported by the IVT output shaft 8. The power circulation mode clutch 27 is composed of, for example, a multi-plate clutch capable of connecting / releasing the gear 26b and the carrier 23. The power circulation mode clutch 27 realizes a power circulation mode in which power is transmitted in a speed ratio range including an infinite speed ratio when connected.

  The rotation of the CVT output shaft 10 is transmitted to the sun gear 22 via the gear train 28. The gear train 28 includes a gear 28 a that is coupled to the CVT output shaft 10 so as to be integrally rotatable, and a gear 28 b that is meshed with the gear 28 a and is coupled to the sun gear 22 so as to be integrally rotatable. Between the gear 28b and the IVT output shaft 8, a direct coupling mode clutch 29 (also referred to as a high clutch) capable of connecting / releasing the gear 28b and the IVT output shaft 8 is interposed. Direct coupling mode clutch 29 realizes a direct coupling mode in which power is transmitted only by CVT 6 when coupled.

In a state where the direct connection mode clutch 29 is released and the power circulation mode clutch 27 is connected, the power of the engine 2 is transmitted to the carrier 23 via the IVT input shaft 5 and the gear train 26, and as a result, the planetary gear mechanism. 7 is transmitted to the IVT output shaft 8 after being amplified in torque.
At this time, the reaction force due to the driving load applied to the ring gear 25 also exerts a torque on the sun gear 22. The torque acting on the sun gear 22 returns to the CVT 6 through the gear train 28 and the CVT output shaft 10, and is combined with the output torque of the engine 2 on the CVT input shaft 9 side via the gear train 26 and the power circulation mode clutch 27. Then, it is transmitted to the carrier 23 again.

That is, the engine power is output to the IVT output shaft 8 and a so-called power circulation mode in which the engine power circulates through the CVT 6 and the planetary gear mechanism 7 is set. This power circulation mode is selected when a large driving torque is required such as when the vehicle starts, when traveling at a low speed, or when suddenly accelerating at a medium speed.
On the other hand, when the power circulation mode clutch 27 is released and the direct connection mode clutch 29 is connected, the power of the engine 2 is transmitted to the sun gear 22 via the CVT 6 and from the IVT output shaft 8 via the direct connection mode clutch 29. Outputs the direct connection mode. This direct connection mode is selected when a large driving torque is not required, such as during medium speed running and during high speed running acceleration.

The oil pressure from the first pump 30 is controlled by the first pressure control valve 31 and supplied to the oil chamber 18 for terminal load and the first oil chamber 20 of the hydraulic cylinder 19. Further, the hydraulic pressure from the second pump 32 is supplied to the second oil chamber 21 of the hydraulic cylinder 19 by being controlled by the second pressure control valve 33.
The control part 34 which controls operation | movement of IVT1 and the engine 2 is comprised by the electronic control unit (ECU: Electronic Control Unit).

  The control unit 34 includes an accelerator operation amount sensor 35 that detects an accelerator operation amount, a vehicle speed sensor 36 that detects a traveling speed of the vehicle, an engine rotation speed sensor 37, and a CVT input shaft that detects the rotation speed of the CVT input shaft 9. A rotational speed sensor 38, a CVT output shaft rotational speed sensor 39 for detecting the rotational speed of the CVT output shaft 10, and a pressure for detecting a differential pressure P between the first oil chamber 20 and the second oil chamber 21 of the hydraulic cylinder 19. A pressure sensor 40 as detection means and an IVT output shaft rotational speed sensor 75 for detecting the rotational speed of the IVT output shaft 8 are connected, and signals from these sensors 36 to 40 and 80 are input to the control unit 34. It has come to be.

  In order to control the engine output, the control unit 34 outputs a command signal to the fuel supply amount adjusting mechanism 41 that adjusts the fuel supply amount to the engine 2, and controls the torque transmission force of the rollers 15 and 16. Therefore, a command signal is output to each of the first pressure control valve 31 and the second pressure control valve 33, and the power circulation mode clutch 27 and the direct connection mode clutch 29 are used for switching between the power circulation mode and the direct connection mode. The contact / separation command signal (see FIG. 3) is output to

  Referring to FIG. 3, the control unit 34 has a plurality of function processing units that are realized in software by a computer executing predetermined program processing. That is, the control unit 34, a driver request conversion unit 42 for obtaining a state quantity for realizing the driving state of the vehicle requested by the driver, a function of controlling the torque of the CVT 6, and a function of switching between the power circulation mode and the direct connection mode. And an engine control unit 44 for controlling the engine 2.

The driver request conversion unit 42 inputs the accelerator operation amount θ detected by the accelerator operation amount sensor 35 and the vehicle speed V detected by the vehicle speed sensor 36, and based on these, the engine 2 receives the maximum efficiency as the state amount. Engine speed ω _{e, T} and target transmission input torque T _{TRN, T} are calculated.
The IVT control unit 43 includes the target transmission input torque T _{TRN, T} given from the driver request conversion unit 42, the CVT input shaft rotational speed ω _i detected by the CVT input shaft rotational speed sensor 38, and the CVT output shaft rotational speed sensor. The CVT output shaft rotational speed ω _o detected by 39 and the differential pressure P detected by the pressure sensor 40 are input, and based on these, for example, the solenoids of the first and second pressure control valves 31 and 33 are respectively supplied A command signal is output. The IVT control unit 43 also detects the CVT input shaft rotational speed ω _i (corresponding to the IVT input shaft rotational speed) detected by the CVT input shaft rotational speed sensor 38, and the IVT output detected by the IVT output shaft rotational speed sensor 80. The shaft rotational speed ω _{IVT, o} is input, and based on these, a contact / separation command signal for mode switching is output to the power circulation mode clutch 27 and the direct connection mode clutch 29.

The engine control unit 44, detected by the target engine rotational speed omega _{e, T,} the engine rotation speed omega _e, CVT input shaft rotation speed sensor 38 which is detected by the engine rotational speed sensor 37 provided from the driver's demand converting section 42 The CVT input shaft rotational speed ω _i , the CVT output shaft rotational speed ω _o detected by the CVT output shaft rotational speed sensor 39, and the differential pressure P detected by the pressure sensor 40 are input, and based on these, the fuel supply amount For example, a signal corresponding to the valve opening command is output to the solenoid of the throttle opening adjusting valve as the adjusting mechanism 41.

Referring to FIG. 4, the driver request conversion unit 42 includes a target engine output calculation unit 45, a target vehicle speed calculation unit 46, a target vehicle speed correction unit 47, and a state quantity calculation unit 48. The target engine output calculation unit 45 receives the accelerator operation amount θ detected by the accelerator operation amount sensor 35 and calculates a target engine output _{Pe, T} using a first engine map 71 stored in advance. The first engine map 71 is a map in which the engine output P corresponding to the accelerator operation amount θ and the vehicle speed V is stored in advance.

The target vehicle speed calculation unit 46 receives the target engine output _{Pe, T} and calculates the target vehicle speed V _T using the second engine map 72 stored in advance. The second engine map 72 stores the relationship between the engine rotational speed ω _e and the engine torque Te that can achieve the maximum efficiency according to the engine output Pe as a maximum efficiency curve (PEC). It is.

When P _v is the vehicle drive power, η _PWT is the drive train efficiency, T _RL is the vehicle running resistance, and ω _W is the drive wheel rotation speed, the vehicle drive power P _v is the engine output Pe and the drive train efficiency. It is equal to the product of η _PWT and equal to the product of the vehicle running resistance T _RL and the drive wheel rotational speed ω _W. That is, the equation P _v = Pe × η _PWT = T _RL × ω _W is established.
Here, the vehicle travel resistance T _RL is expressed as a function T _RL (ω _W ) of the drive wheel rotational speed ω _W. That is, the expression T _RL = T _RL (ω _W ) is established. Therefore, the drive wheel rotational speed ω _W can be expressed as a function of the engine output Pe. That is, the formula ω _W = ω _W (Pe) is established. Therefore, the second engine map of the 72 and the target engine output P _e, using _T, the target driving wheel rotational speed, i.e., it is possible to determine the target vehicle speed V _T.

The calculated target vehicle speed V _T is output to the target vehicle speed correction unit 47.
The target vehicle speed correcting section 47 inputs the target vehicle speed V _T above, the deviation (V _T -V) between the actual vehicle speed V by detecting the target vehicle speed V _T and the vehicle speed sensor 36, the control gain multiplication unit 49 The corrected target vehicle speed V _AT is obtained by multiplying the control gain k 1 and adding the obtained correction amount k 1 × (V _T −V) to the target vehicle speed V _T.

That is, the corrected target vehicle speed V _AT is obtained based on the following formula (1).
V _AT = V _T + k1 × (V _T −V) (1)
The obtained corrected target vehicle speed V _AT is output to the state quantity calculation unit 48. The state quantity calculation unit 48 inputs the above-mentioned correction target vehicle speed V _AT, on the basis of the corrected target vehicle speed V _AT, the target engine rotational speed omega _{e, T} and the target transmission input torque for providing the maximum efficiency to the engine 2 T _{TRN, T} is calculated.

Specifically, the state quantity calculation unit 48 includes a corrected target engine output calculation unit 50, a target engine speed and target engine torque calculation unit 51 as a target engine performance calculation unit, and a target transmission input torque calculation unit 52. And.
The corrected target engine output calculation unit 50 receives the corrected target vehicle speed V _AT and calculates the corrected target engine output _{Pe, AT} according to the corrected target vehicle speed V _AT using the first engine map 71 described above. To do. That is, a boosted target engine output is obtained.

The calculated corrected target engine output _{Pe, AT} is output to the target engine rotation speed and target engine torque calculation unit 51. The target engine speed and target engine torque calculation unit 51 receives the corrected target engine output P _{e, AT} and uses the second engine map 72 to determine the target engine speed ω _{e, T} and the target The engine torque _{Te, T} is calculated. At this time, the target engine speed ω _{e, T} and the target engine torque _{Te, T} are calculated in accordance with the maximum efficiency curve (PEC), so that the drive control that improves the fuel efficiency without impairing the acceleration performance is effective. There will be something.

The calculated target engine rotational speed ω _{e, T} and target engine torque _{Te, T} calculated by the target engine rotational speed and target engine torque calculating unit 51 are output to the target transmission input torque calculating unit 52 while being calculated. The target engine speed ω _{e, T} thus output is output to the engine control unit 44.
Target transmission input torque computing section 52, above the target engine rotational speed omega _{e, T} and the target engine torque T _e, and enter the _T, using the formula (2) below, the target transmission input torque T _TRN, the _T Calculate.

T _{TRN, T} = T _{e, T} (2)
From equation (2), the target transmission input torque T _{TRN, T} is obtained.
Next, referring to FIG. 5, the IVT control unit 43 includes an actual transmission input torque calculation unit 53, a target transmission input torque correction unit 54 as a CVT torque control unit, a required differential pressure calculation unit 55, and a signal output unit. 56 and a mode switching unit 76.

The mode switching unit 76 detects the CVT input shaft rotational speed ω _i (corresponding to the IVT input shaft rotational speed) detected by the CVT input shaft rotational speed sensor 38, and the IVT output shaft rotational speed detected by the IVT output shaft rotational speed sensor 75. Based on the speed ω _{IVT, o} , the IVT transmission ratio is calculated, and the mode is switched by outputting a contact / separation command signal to the power circulation mode clutch 27 and the direct connection mode clutch 29 according to the obtained IVT transmission ratio.

The actual transmission input torque calculation unit 53 includes a CVT input shaft rotational speed ω _i detected by the CVT input shaft rotational speed sensor 38, a CVT output shaft rotational speed ω _o detected by the CVT output shaft rotational speed sensor 39, and a pressure sensor. The differential pressure P between the first and second oil chambers 20 and 21 detected by 40 is input, and the actual transmission input torque T _{TRN, R} is calculated based on the following equation (3) (however, This is an example of the direct connection mode.)

T _{TRN, R} = kr × [Rv / (Rv−1)] × P (3)
However,
kr: Geometric constant Rv: Gear ratio of CVT (Rv = ω _o / ω _i )
ω _i : CVT input shaft rotation speed ω _o : CVT output shaft rotation speed The target transmission input torque correction unit 54 inputs the actual transmission input torque T _{TRN, R} calculated by the actual transmission input torque calculation unit 53, Control is performed on a deviation (T _{TRN, T} −T _{TRN, R} ) between the transmission input torque T _{TRN, R} and the target transmission input torque T _{TRN, T} given from the target transmission input torque calculation unit 52 of the operation request conversion unit 42. The gain multiplication unit 57 multiplies the control gain k2 and adds the obtained correction amount k2 × (T _{TRN, T} −T _{TRN, R} ) to the target transmission input torque T _{TRN, T} , thereby correcting the target transmission input torque T _{Get TRN, AT} .

That is, the corrected target transmission input torque T _{TRN, AT} is obtained based on the following equation (4).
T _{TRN, AT} = T _{TRN, T} + k 2 × (T _{TRN, T} −T _{TRN, R} ) (4)
The required differential pressure calculation unit 55 inputs the corrected target transmission input torque T _{TRN, AT} calculated by the target transmission input torque correction unit 54 and also calculates the CVT input shaft rotational speed ω _i to calculate the transmission ratio Rv of the CVT 6. And the CVT output shaft rotational speed ω _o are input and applied between the first and second oil chambers 20 and 21 of the hydraulic cylinder 19 using the following linearized inverse function model equation (5). should, it calculates the required differential pressure P _D (although this is an example in the case of direct mode.).

P _D = T _{TRN, AT} / [kr × Rv / (Rv−1)] (5)
Signal output unit 56 receives the request differential pressure P _D which is calculated by the required differential pressure calculating section 55, which voltage command signal for each solenoid of the first pressure control valve 31 and the second pressure control valve 33 It will be converted and output. As a result, a desired reaction force can be applied to the rollers 15 and 16 and a desired transmission torque can be transmitted to the CVT 6.

Next, referring to FIG. 6, the engine control unit 44 includes a target engine rotational acceleration calculation unit 58, an actual transmission input torque calculation unit 59, a requested engine torque calculation unit 60, and a signal output unit 61.
The target engine rotation acceleration calculation unit 58 is configured to detect the target engine rotation speed ω _{e, T} input from the target engine rotation speed and target engine torque calculation unit 51 of the driver request conversion unit 42 and the engine rotation detected by the engine rotation speed sensor 37. The target engine rotational acceleration ω ′ _{e, AT} is obtained by multiplying the deviation (ω _{e, T} −ω _e ) from the speed ω _e by the control gain k 3 in the control gain multiplier 62. That is, ω ′ _{e, AT} = k3 × (ω _{e, T} −ω _e ). The calculated target engine rotational acceleration ω ′ _{e, AT} is output to the required engine torque calculation unit 60.

The actual transmission input torque calculation unit 59 includes a CVT input shaft rotational speed ω _i detected by the CVT input shaft rotational speed sensor 38, a CVT output shaft rotational speed ω _o detected by the CVT output shaft rotational speed sensor 39, and a pressure sensor. The differential pressure P between the first and second oil chambers 20 and 21 detected by 40 is input, and the actual transmission input torque T _{TRN, R} is calculated based on the above equation (3). The calculated actual transmission input torque T _{TRN, R} is output to the required engine torque calculation unit 60.

The requested engine torque calculation unit 60 inputs the target engine rotational acceleration ω ′ _{e, AT} and the actual transmission input torque T _{TRN, R} described above, and calculates the requested engine torque _{Te , D} using the following equation (6). Calculate.
T _{e, D} = I _e × ω ′ _{e, AT} + T _{TRN, R} (6)
However,
Ie: Engine inertia, Ie × ω ′ _{e, AT on} the right side of the equation (6) corresponds to the inertia torque of the engine. The required engine torque _{Te, D} is obtained by adding the actual transmission input torque _{TTRN, R} to the inertia torque of the engine.

The signal output unit 61 receives the requested engine torque _{Te, D} calculated by the requested engine torque calculating unit 60, and uses it as a fuel supply amount adjusting mechanism 41 for, for example, a solenoid of a solenoid valve for adjusting the throttle valve opening. It is converted into a voltage command signal and output. As a result, the engine 2 can exhibit desired power characteristics.
According to this embodiment, there are the following excellent advantages. That is, the target engine speed ω _{e, T} and the target transmission input torque that can give the engine 2 the maximum efficiency for the request that the driver asks the vehicle via the accelerator pedal by the function of the driver request conversion unit 42. The state quantity is converted to T _{TRN, T.} As a result, the engine 2 can be operated at the maximum efficiency without impairing the acceleration performance of the vehicle as much as possible according to the driver's request. As a result, both fuel consumption and drivability can be achieved.

Further, the driver's demand converting section 42, the target vehicle speed correcting section 47, by correcting the target vehicle speed V _T based on a comparison between the actual vehicle speed V and the target vehicle speed V _T, to meet the requirements of the driver The engine power can be artificially boosted. In particular, by comparing the actual vehicle speed V, since the specifically corrects the target vehicle speed V _T by using the difference between the actual vehicle speed V and the target vehicle speed V _T (V _T -V), the control loop low volume Can be

Further, the target vehicle speed correction unit 47 calculates a correction amount k1 × (V _T −V) obtained by multiplying a deviation (V _T −V) between the target vehicle speed V _T and the actual vehicle speed V by a predetermined gain k1. The corrected target vehicle speed V _AT is obtained by adding to the vehicle speed target vehicle speed V _T. Since a single gain k1 is used, the transient characteristics can be easily tuned in the power control of the engine 2. Also, the control loop is simple and inexpensive. In other words, it is possible to provide a shift kick-down function at low cost.

The driver request conversion unit 42 corrects the target vehicle speed V _T according to the driver's request, and corrects the target engine output according to the obtained corrected target vehicle speed V _AT . Therefore, the engine output is boosted according to the driver's request. The target value of the engine output to be boosted (target engine rotational speed omega _{e, T} and the target engine torque T _{e, T)} is accordance with the maximum efficiency curve (PEC) in relation to the engine rotational speed omega _e and the engine torque T _e Is calculated. As a result, it is effective to improve fuel efficiency without impairing acceleration.

Further, since engine load torque control via the torque control type CVT 6 is added to the engine control, optimal control is possible.
That is, when the torque control type CVT 6 is used in such a manner that the power flow is controlled like the IVT, the engine inertia is separated from the vehicle inertia. In other words, directly to the engine torque T _e is the driven wheel speed (substantially corresponding to the vehicle speed V), no effect. Under such a premise, the torque control of the CVT 6 by the IVT control unit 43 and the torque control of the engine 2 by the engine control unit 44 are combined to control the power flow of the system. The above equation (6) according to the second law is used.

Thus, during transient operation of the drive control, power flow to the drive wheels from the engine 2 (positive flow: engine torque T _e is the actual transmission input torque T _TRN, greater than _R Condition: T _e> T _{TRN, R} ) Can be maintained. That is, when the accelerator is depressed, a phenomenon in which undershoot occurs at the initial response time, that is, a so-called NMP (non minimum phase), can be prevented at the rotational speed of the driving wheel that responds to the accelerator. As a result, drivability and fuel consumption can be improved.

Further, in the torque control of the CVT 6 by the IVT control unit 43 and the torque control of the engine 2 by the engine control unit 44, since the single control gains k2 and k3 are used, the control is simple and inexpensive.
Further, the engine control unit 44 serves to separate the engine response from the input torque (load) of the CVT 6 and linearize the engine speed response so that the system response is monotonously increased (decreased) in the primary system. Fulfill. Therefore, there is an advantage that the rotational speed ω _e of the engine 2 and the rotational speed of the drive wheels (substantially equivalent to the vehicle speed V) can be stably responded regardless of the control gains k2 and k3.

Of the above formulas (1) to (6), formulas (1), (2), (4), and (6) are formulas that can be adopted regardless of whether they are in direct connection mode or power circulation mode. Expressions (3) and (5) are expressions that match the example of the direct connection mode.
7 to 10 show another embodiment of the present invention. In other words, the above-described embodiment shown in FIGS. 1 to 6 is an embodiment related to a drive control device for a vehicle having an IVT, but this embodiment includes a torque control type CVT that does not constitute an IVT. 1 is an embodiment according to a vehicle drive control device.

  Referring to FIG. 7, the present embodiment is mainly different from the embodiment of FIG. 1 in that planetary gear mechanism 7, IVT output shaft 8, gear trains 26 and 28, power circulation mode clutch 27, direct connection mode clutch. 29, IVT output shaft rotational speed sensor 75 is abolished. The CVT output shaft 10 is connected to the drive wheels 83 via a gear train 80, a differential device 81 and a drive shaft 82. The gear train 80 includes a gear 80 a that rotates integrally with the CVT output shaft 10, and a gear 80 b that meshes with the gear 80 a and rotates integrally with the case of the differential device 81.

Referring to FIG. 8, control unit 34 </ b> A of the present embodiment is mainly different from control unit 34 of the embodiment of FIG. 3 in that CVT control unit 43 </ b> A is provided instead of IVT control unit 43. It is in the point. In the present embodiment, the target transmission input torque T _{TRN, T} given from the driving vehicle request conversion unit 42 to the CVT control unit 43A corresponds to the target CVT input torque.
Referring to FIG. 9, the target transmission input torque T _{TRN, T} calculated by the target transmission input torque calculation unit 52 of the driver request conversion unit 42 of the control unit 34A of the present embodiment is the CVT control unit 43A. Given to.

Referring to FIG. 10, the main difference between CVT control unit 43A of the present embodiment and IVT control unit 43 of FIG. 5 is that mode switching unit 76 is eliminated. In the present embodiment, the actual transmission input torque T _{TRN, R} calculated by the actual transmission input torque calculation unit 53 in FIG. 10 corresponds to the actual CVT input torque (actual CVT input torque).

Further, in the present embodiment, the engine control unit 44 has the same configuration as that of the embodiment of FIG.
Also in this embodiment, the same operational effects as those of the embodiment of FIGS. 1 to 6 can be obtained, and both fuel efficiency and drivability can be achieved.
The present invention is not limited to the above embodiment, and the planetary gear mechanism 7 includes elements connected to the CVT input shaft 9, elements connected to the CVT output shaft 10, and elements connected to the drive wheels. It only has to have. Instead of at least one of the gear trains 26 and 28, a chain / sprocket mechanism may be used. The CVT is not limited to the full toroidal type, but may be a half toroidal type, or may be a belt type, a chain type, or other various types of CVTs. In addition, various modifications can be made within the scope of the claims of the present invention.

  In the same control configuration as that of the embodiment of FIGS. 1 to 6, the control gain k1 of the target vehicle speed correction unit 47 of FIG. 4 is made relatively small to boost the engine output, and the control gain k1 is made relatively The response time from the operation of the accelerator pedal to the start of the change in the vehicle speed is calculated by simulation using Example 2 in which the engine output is boosted and the target vehicle speed correction unit is abolished. When confirmed, the results shown in FIG. 11 were obtained.

  From the test results, it was proved that the responsiveness of Examples 1 and 2 in which the engine output is boosted by correcting the target vehicle speed according to the driver's request is remarkably superior to that of Comparative Example 1.

1 is a schematic diagram illustrating a schematic configuration of a vehicle to which a vehicle drive control device according to an embodiment of the present invention is applied. It is the schematic of the principal part of CVT. It is a block diagram which shows schematic structure of a control part. It is a block diagram which shows schematic structure of a driver | operator request | requirement conversion part. It is a block diagram which shows schematic structure of an IVT control part. It is a block diagram which shows schematic structure of an engine control part. It is a schematic diagram which shows schematic structure of the vehicle to which the drive control apparatus of the vehicle of another embodiment of this invention was applied. It is a block diagram which shows schematic structure of the control part of embodiment of FIG. It is a block diagram which shows schematic structure of the driver | operator request | requirement conversion part of embodiment of FIG. It is a block diagram which shows schematic structure of the CVT control part of embodiment of FIG. It is a graph which shows the relationship between the response time when a vehicle speed starts a change from operation of an arsel pedal, and a vehicle speed level.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... IVT, 2 ... Engine, 5 ... IVT input shaft, 6 ... CVT, 7 ... Planetary gear mechanism, 8 ... IVT output shaft, 9 ... CVT input shaft, 10 ... CVT output shaft, 11, 12 ... Input disk, 13 , 14 ... Output disk, 15, 16 ... Roller, 17 ... Carriage, 18 ... Oil chamber, 19 ... Hydraulic cylinder, 20 ... First oil chamber, 21 ... Second oil chamber, 27 ... Power circulation mode clutch, 29 DESCRIPTION OF SYMBOLS ... Direct connection mode clutch, 31 ... 1st pressure control valve, 33 ... 2nd pressure control valve, 34, 34A ... Control part, 35 ... Accelerator operation amount sensor, 36 ... Vehicle speed sensor, 37 ... Engine rotation speed sensor, 38 ... CVT input shaft rotational speed sensor, 39 ... CVT output shaft rotational speed sensor, 40 ... Pressure sensor, 41 ... Fuel supply amount adjustment mechanism, 42 ... Driver request conversion section, 43 ... IVT control section (CVT transmission torque Control unit), 43A ... CVT control unit, 44 ... engine control unit, 46 ... target vehicle speed calculation unit, 47 ... target vehicle speed correction unit, 48 ... state quantity calculation unit, 51 ... target engine speed and Target engine torque calculation unit (target engine performance calculation unit) 52 ... Target transmission input torque calculation unit, θ ... Accelerator operation amount, V ... Vehicle speed, ω _{e, T} ... Target engine rotation speed, T _{TRN, T} ... Target transmission input Torque, V _T ... target vehicle speed, V _AT ... corrected target vehicle speed, k1 ... control gain.

Claims (8)

A torque-controlled continuously variable transmission mechanism (hereinafter referred to as CVT) capable of changing the gear ratio steplessly;
An accelerator operation amount detecting means for detecting an accelerator operation amount;
Vehicle speed detection means for detecting the speed of the vehicle;
A control unit for controlling the operation of the CVT and the engine,
The control unit includes a driver request conversion unit for obtaining a state quantity for realizing the driving state of the vehicle requested by the driver,
The driver request conversion unit is a target engine rotational speed for giving the engine maximum efficiency as the state quantity based on the accelerator operation amount detected by the accelerator operation amount detection means and the vehicle speed detected by the vehicle speed detection means. And a vehicle drive control device, which calculates a target transmission input torque. A torque-controlled continuously variable transmission mechanism (hereinafter referred to as CVT) capable of changing the transmission gear ratio steplessly, a planetary gear mechanism interposed between the input shaft and the output shaft of the CVT, and an infinite transmission gear ratio Including a power circulation mode clutch that is coupled when realizing a power circulation mode that transmits power in a speed ratio range that includes a direct coupling mode clutch that is coupled when realizing a direct connection mode that transmits power only by CVT. An infinitely variable transmission continuously variable transmission (hereinafter referred to as IVT),
An accelerator operation amount detecting means for detecting an accelerator operation amount;
Vehicle speed detection means for detecting the speed of the vehicle;
A control unit for controlling the operation of the IVT and the engine,
The control unit includes a driver request conversion unit for obtaining a state quantity for realizing the driving state of the vehicle requested by the driver,
The driver request conversion unit is a target engine rotational speed for giving the engine maximum efficiency as the state quantity based on the accelerator operation amount detected by the accelerator operation amount detection means and the vehicle speed detected by the vehicle speed detection means. And a vehicle drive control device, which calculates a target transmission input torque. In Claim 1 or 2, the driver request conversion unit,
A target vehicle speed calculation unit that calculates a target vehicle speed based on the detected accelerator operation amount and the detected vehicle speed;
A target vehicle speed correction unit that corrects the target vehicle speed to obtain a corrected target vehicle speed based on a comparison between the target vehicle speed calculated by the target vehicle speed calculation unit and the detected vehicle speed;
A vehicle drive control device comprising: a state quantity calculation unit for calculating a target engine speed and a target transmission input torque based on the corrected target vehicle speed.   The target vehicle speed correction unit according to claim 3, wherein the target vehicle speed correction unit adds a correction amount obtained by multiplying the target vehicle speed calculated by the target vehicle speed calculation unit and the detected vehicle speed by a predetermined gain to the target vehicle speed, thereby correcting the target vehicle speed. A vehicle drive control device characterized in that a target vehicle speed is obtained. In Claim 3 or 4, the state quantity calculation unit comprises:
Based on the engine output corresponding to the corrected target vehicle speed, a target engine performance calculation unit that calculates a target engine speed and target engine torque for giving the engine maximum efficiency, and a target engine speed calculated by the target engine performance calculation unit And a target transmission input torque calculation unit that calculates a target transmission input torque based on the speed and the target engine torque.   6. The control unit according to claim 5, wherein the control unit includes a control unit for controlling CVT transmission torque, and the target transmission input torque calculated by the target transmission input torque calculation unit controls the transmission torque of the CVT. A drive control apparatus for a vehicle, wherein   7. The control unit according to claim 6, wherein the control unit includes an engine control unit for controlling engine torque, and the target engine speed calculated by the target engine performance calculation unit is output to the engine control unit. A vehicle drive control device.   8. The vehicle drive control device according to claim 6, wherein the CVT includes a full toroidal CVT.

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