JP2002333063A - Shift control device for continuously variable transmission of infinite change gear ratio - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of the gear-shift shock when the driving condition is changed during the mode change. SOLUTION: The shift control device comprises a phase order setting means, a clutch torque target value generating means 133, a target IVT shift speed calculating means 122, and a target CVT shift speed calculation means 123. The phase order setting means sets the order of the torque phase and the inertia phase based on the direction of change of the total change gear ratio and the positive/negative of the steady engine torque. The clutch torque target producing means 133 calculates the target values of the transmission torque of a power circulating clutch and a direct-coupled clutch respectively based on the CVT gear ratio, the engine torque, and the set phase. The target IVT shift speed calculating means 122 calculates the target IVT shift speed from the IVT change gear ratio and the target IVT change gear ratio. The target CVT shift speed calculating means 123 calculates the target CVT shift speed based on the engine torque, the clutch transmission torque target value, and the target IVT shift speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a shift control device for a continuously variable transmission with an infinite speed ratio, which is employed in a vehicle or the like.

[0002]

2. Description of the Related Art Conventionally, a belt-type or toroidal-type continuously variable transmission mechanism is known as a vehicle transmission. In order to further expand the speed change range of such a continuously variable transmission mechanism,
2. Description of the Related Art A continuously variable transmission with an infinitely variable transmission ratio capable of controlling a transmission ratio to infinity by combining a constant transmission mechanism and a planetary gear mechanism with a continuously variable transmission mechanism is known.

[0003] This is a half toroidal type continuously variable transmission mechanism capable of continuously changing the transmission ratio and a constant transmission mechanism (reduction mechanism) on a unit input shaft of a continuously variable transmission having an infinite transmission ratio connected to an engine. ) Are connected in parallel, and these output shafts are connected by a planetary gear mechanism. The output of the continuously variable transmission mechanism is connected to the sun gear of the planetary gear mechanism, and the output shaft of the constant transmission mechanism is connected via a power circulation clutch. It is connected to the carrier of the planetary gear mechanism.

[0004] The output shaft of the continuously variable transmission mechanism connected to the sun gear is selectively coupled to a unit output shaft, which is the output shaft of a continuously variable transmission with an infinite transmission ratio, via a direct coupling clutch.
The ring gear of the planetary gear mechanism is connected to the unit output shaft.

In such a continuously variable transmission with an infinite transmission ratio,
As shown in FIG. 20, by disengaging the direct coupling clutch while engaging the power circulation clutch, the IVT speed ratio (hereinafter, IVT speed ratio i) is set according to the speed ratio difference between the continuously variable transmission mechanism and the constant transmission mechanism. The unit input shaft speed / unit output shaft speed is infinite from negative to positive (1
In / i = 0 and the power recirculation mode for continuously shift control include gears that de neutral point GNP), while releasing the power recirculation clutch, enters into direct clutch to the gear ratio i _c of the continuously variable transmission mechanism Accordingly, two operation modes of the direct connection mode in which the shift control is performed can be selectively used.

[0006] In FIG. 20, the inverse i _i the vertical axis IVT gear ratio i, the horizontal axis as the shift ratio i _c of the continuously variable transmission mechanism, the continuously variable transmission mechanism the speed ratio i _c and forward and backward relationship Are displayed continuously.

Switching between power circulation mode and direct connection mode
Indicates the CVT speed ratio i in the power circulation mode and the direct connection mode._cBut
Matching rotation synchronization point RSP (Revolution Synchronous
 Point), the IVT corresponding to the rotation synchronization point RSP
Transmission ratio i_r(CVT gear ratio = i_{c r}),
By switching the clutch, it is possible to switch directly to the power circulation mode.
Switching of the connection mode (mode switching) is possible
While the clutch is switched, the CVT change
It is necessary to fix the speed ratio, and the change in the IVT speed ratio
The vehicle stops, causing an uncomfortable shift.

To solve this problem, Japanese Patent Application Laid-Open No. 2001-505
No. 35 discloses a technique for performing mode switching without passing through the rotation synchronization point RSP.

This is because when switching the clutch,
The hydraulic pressure target values of the power circulating clutch and the direct coupling clutch are given in a feedforward manner, and during the shift time determined by the operating state of the vehicle, each hydraulic pressure is given by a ramp function, and the CVT gear ratio is determined by the operating state of the vehicle. That is, the CVT speed ratio is set by feedforward independently of the power circulation mode mode and the direct connection clutch.

That is, when a shift accompanied by a mode change (upshift from the power circulation mode to the direct connection mode) as shown in FIGS. 21 (a) and 21 (b) and a fast shift is demanded, The gear is shifted toward (b) while the clutch is slipping without causing the CVT speed ratio to reach the RSP once.

[0011]

However, in the above conventional example, the hydraulic pressure applied to the power circulating clutch and the direct coupling clutch operated at the time of mode switching and the CVT speed ratio are set in a feed-forward manner according to the operating state of the vehicle. However, when the operation state at the start of mode switching and at the end of mode switching changes, the IVT at the end of mode switching is changed.
The speed ratio and the target IVT speed ratio may deviate, and at this time, a speed change shock occurs.

In the above conventional example, a power circulation clutch,
Since the direct-coupled clutch and the CVT gear ratio are controlled independently of each other, when the operating state changes, a shift shock occurs when the clutch engagement timing or the disengagement timing does not match the CVT gear shift timing.

In order to set the CVT speed ratio, the clutch transmission torque and the target value of the engine torque at the time of mode switching so as to reduce the shift shock, a number of experiments and simulations are performed to set the target values for each operating state. Because of the necessity, there is a problem that a development period and a development cost increase.

The present invention has been made in view of the above problems, and prevents a shift shock from occurring even if the operating state changes during mode switching, and further suppresses an increase in development costs. Aim.

[0015]

According to a first aspect of the present invention, a continuously variable transmission mechanism capable of continuously changing a gear ratio and a constant transmission mechanism are connected to a unit input shaft, respectively. The infinitely variable speed ratio transmission in which the output shaft of the mechanism is connected to the unit output shaft via a planetary gear mechanism, a power circulation clutch and a direct coupling clutch, the power circulation clutch is engaged, the direct coupling clutch is released, and the total transmission is released. Mode switching control means for switching between a power circulation mode for transmitting power including an infinite ratio, and a direct connection mode for transmitting power according to a continuously variable transmission mechanism by engaging a direct coupling clutch, releasing the power circulation clutch, and A CVT speed ratio detecting means for detecting a speed ratio of the continuously variable transmission mechanism, and a total speed ratio of the infinitely variable speed continuously variable transmission. Speed ratio detecting means for detecting the rotation speed of the unit output shaft, IVT output shaft speed detecting means for detecting the rotation speed of the unit output shaft, throttle opening degree detecting means for detecting the throttle opening degree, the output shaft speed and the throttle opening degree. And a target IVT speed ratio generating means for calculating a target total speed ratio based on the reached total speed ratio, a target IVT speed ratio generating means for calculating a target total speed ratio based on the reached total speed ratio, Speed change direction determining means for determining the change direction of the total speed ratio from the ratio, actual engine torque detecting means for detecting or estimating the actual engine torque, and estimating the value of the engine torque after the end of the change at the start of the change of the engine torque. Steady engine torque estimating means; steady engine torque positive / negative determining means for determining whether the steady engine torque is positive or negative; A torque phase for increasing the absolute value of the transmission torque on the engaged side of the power circulating clutch and the direct coupling clutch based on the positive and negative of the torque, and a side engaged while suppressing slippage of the power circulating clutch and the direct coupling clutch. Phase order setting means for setting which phase to start from among the inertia phases that are changed so that the input / output rotational speeds of the continuously variable transmission mechanism and the actual engine torque are set. Clutch torque target value generating means for calculating target values of the transmission torques of the power circulating clutch and the direct coupling clutch based on the phase; and calculating the target gear speed of the total gear ratio from the detected total gear ratio and the target gear ratio. Target IVT shift speed calculating means, and a target speed of the engine torque, the clutch transmission torque target value, and the total speed ratio. A target CVT shift speed calculating means for calculating a target shift speed of the continuously variable transmission mechanism based on the target shift speed.

In a second aspect based on the first aspect, the target CVT shift speed calculating means multiplies a transmission torque target value of the power circulating clutch when calculating the target shift speed of the continuously variable transmission mechanism. And the coefficient multiplied by the target transmission torque of the direct coupling clutch, the coefficient multiplied by the actual engine torque, and the coefficient multiplied by the target transmission speed of the total transmission ratio are integrated with the target transmission speed of the continuously variable transmission mechanism. The correction is made in accordance with the target gear ratio obtained as described above or the detected gear ratio of the continuously variable transmission mechanism.

In a third aspect, the first or second aspect is provided.
In the invention, the target CVT shift speed calculating means includes:
It has a rotation speed detection unit for detecting the sun gear rotation speed and the ring gear rotation speed of the planetary gear mechanism, and multiplies the transmission torque target value of the power circulation clutch when calculating the target shift speed of the continuously variable transmission mechanism. The correction is made according to the coefficient, the coefficient multiplied by the target value of the transmission torque of the direct coupling clutch, the coefficient multiplied by the actual engine torque, and the detected values of the sun gear rotation speed and the ring gear rotation speed.

Further, the fourth invention is directed to the first to third embodiments.
In any one of the inventions, the target CVT speed change calculating means includes a running load detecting means for detecting a running load, and calculates the target CVT speed based on a detected value of the running load.

[0019]

Therefore, the first aspect of the present invention is to change the phase order of the torque phase and the inertia phase based on the switching pattern of the operation mode set in advance from the change direction of the total gear ratio and the positive / negative of the steady engine torque. Give in a preset pattern. The power circulation clutch transmission torque target value and the direct coupling clutch transmission torque target value are set based on the phase order, the actual engine torque, and the speed ratio of the continuously variable transmission mechanism. Compensation for the deviation between the target total gear ratio and the actual total gear ratio
This is performed at the target speed of the continuously variable transmission mechanism based on the target speed of the total speed ratio.

When compensating for the deviation between the target total speed ratio (IVT speed ratio) and the total speed ratio (IVT speed ratio) in the mode switching, the deviation between the target total speed ratio and the total speed ratio while sliding the clutch. Target shift speed of the total speed ratio based on
Since the target shift speed of the continuously variable transmission mechanism is set according to the change in the clutch transmission torque and the engine torque, the target total speed ratio and the total speed ratio can be set without giving a target value based on many experiments and simulations. Since the deviation can be corrected by the continuously variable transmission mechanism, it is possible to perform the shift while suppressing the shift shock without increasing the development time and the development cost.

According to the second aspect of the present invention, the sensitivity when the transmission torque of the power circulating clutch, the transmission torque of the direct coupling clutch, the actual engine torque, and the speed of the continuously variable transmission mechanism affect the speed of the total speed ratio is reduced. The coefficient multiplied by the target value of the power-circulating clutch transmission torque and the coefficient multiplied by the target value of the direct-coupled clutch transmission torque when calculating the target shift speed, taking into account that the coefficient changes according to the speed ratio of the continuously variable transmission mechanism. The coefficient multiplied by the actual engine torque and the coefficient multiplied by the target transmission speed of the total transmission ratio are corrected according to the target transmission ratio obtained by integrating the target transmission speed of the continuously variable transmission mechanism or the detected transmission ratio. Therefore, the target gear speed of the continuously variable transmission mechanism that is adapted to the sensitivity that changes according to the gear ratio of the continuously variable transmission mechanism is calculated, and the mode switching is performed while taking into account the operating state of the continuously variable transmission with infinite transmission ratio more reliably. Do this Since it is the response of the overall gear ratio to a target overall gear ratio becomes closer to the desired properties, the occurrence of shift shock can be reliably suppressed.

According to the third aspect of the present invention, the sensitivity when the transmission torque of the power circulation clutch, the transmission torque of the direct coupling clutch, the actual engine torque, and the speed of the continuously variable transmission mechanism affect the speed of the total speed ratio is a sun gear. Considering that the speed changes according to the rotation speed and the ring gear rotation speed, the coefficient multiplied by the power circulation clutch transmission torque target value and the direct coupling clutch transmission torque target value were calculated when calculating the target shift speed of the continuously variable transmission mechanism. The coefficient, the coefficient multiplied by the actual engine torque, and the coefficient multiplied by the target transmission speed of the total gear ratio are corrected according to the rotation speeds of the ring gear and the sun gear. The target shift speed of the continuously variable transmission mechanism adapted to the sensitivity that changes accordingly is calculated, and the mode can be switched while the operation state of the continuously variable transmission with infinite gear ratio is more reliably considered. The response of the overall gear ratio to a target overall gear ratio becomes closer to the desired properties, it is possible to reliably suppress the occurrence of shift shock.

According to the fourth aspect, the target shift speed of the continuously variable transmission is calculated based on the running load.
Control according to the change in the running load due to the influence of the road gradient or road surface condition becomes possible, and smooth mode switching becomes possible even in a situation where the running load changes, such as on an uphill road.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an example in which a continuously variable transmission (IVT) having an infinite speed ratio is formed by using a toroidal type continuously variable transmission mechanism 2 of a double cavity type constituted by a half toroid.

In FIG. 1, a continuously variable transmission with an infinite transmission ratio is provided with a toroidal type continuously variable transmission capable of continuously changing the transmission ratio on a unit input shaft 1 connected to a crankshaft (not shown) of an engine. The mechanism 2 is connected in parallel with a constant speed change mechanism 3 (reduction gear) composed of a gear 3a and a gear 3b, and these output shafts 4 and 3c are arranged on the unit output shaft 6 side and a planetary gear mechanism. 5 linked together.

The output shaft 4 of the continuously variable transmission mechanism has a unit output shaft 6
The output sprocket 2a, the chain 4b, and the sprocket 4a of the continuously variable transmission mechanism 2 are coaxially and rotatably supported with each other, and one end of the continuously variable transmission mechanism output shaft 4 is connected to the planetary gear mechanism 5. The other end is connected to the direct coupling clutch 10.

The output shaft 3c of the constant speed change mechanism 3 connected to the gear 3b is also supported coaxially with the unit output shaft 6 so as to be rotatable relative to the unit output shaft 6, and the planetary gear mechanism 5 is connected via a power circulation clutch 9 (first clutch). The ring gear 5c of the planetary gear mechanism 5 is connected to a unit output shaft 6 which is an output shaft of a continuously variable transmission with an infinite transmission ratio.

A transmission output gear 7 is provided on the right side of the unit output shaft 6 in the figure, and the transmission output gear 7 meshes with the final gear 12 of the differential gear 8 and is connected to the differential gear 8. Drive shaft 1
Reference numeral 1 denotes a speed ratio _ic of the continuously variable transmission mechanism 2 and an IVT speed ratio (unit input shaft speed / unit output shaft speed = total speed ratio, hereinafter referred to as i) corresponding to the operation mode, and the driving force is Is transmitted.

The continuously variable transmission (CVT) 2 is shown in FIGS.
As shown in FIG. 2, the input rollers 21 and the output disk 22 are of a double-cavity toroidal type which sandwiches and presses the power rollers 20, 20, respectively. The power rollers 20 are connected to a trunnion 23 via a pivot shaft 24. It is rotatably supported by.

The rotation angle of the trunnion 23 is
As will be described later, the inclination angle of the power roller 20 (hereinafter referred to as the inclination angle) is changed by changing the step angle of the step motor 52 according to the number of steps, and the CV of the continuously variable transmission mechanism 2 is changed.
And T speed ratio i _c, the IVT speed ratio i can be changed steplessly.

The relationship between the speed ratio i _c of the continuously variable transmission mechanism 2, the inverse i _i of IVT gear ratio i becomes the same manner as the conventional example Figure 20.

In FIG. 20, the power circulation clutch 9
In the power circulation mode in which the direct coupling clutch 10 is released, the IVT speed ratio i is set to infinity on both the forward side and the reverse side in accordance with the speed difference between the continuously variable transmission mechanism 2 and the constant transmission mechanism 3 (see FIG. Medium geared neutral point GNP 1 /
i = 0).

Further, in the direct connection mode in which the power-circulating clutch 9 is released and the direct connection clutch 10 is engaged, the shift control according to the speed ratio _ic of the continuously variable transmission mechanism 2 can be performed.

The engaging force of the power circulation clutch 9 is determined by the hydraulic pressure supplied to the first hydraulic servo 92 from the first solenoid valve 91, and the engaging force of the direct coupling clutch 10 is applied to the second hydraulic servo 102 by the second solenoid valve 101. Determined by the hydraulic pressure supplied from the

As shown in FIG. 2, each power roller 20 of the toroidal type continuously variable transmission 2 has a lower end connected to a hydraulic cylinder 50 so as to be axially displaceable and rotatable about an axis. 23 (power roller support member)
Is supported by each. In addition, between the power roller 20 and the trunnion 23, a swingable pivot shaft 24 is provided.
Is interposed.

The hydraulic cylinder 50 has upper and lower oil chambers 50a, 50b defined by a piston 51, and the hydraulic cylinders 5 of the trunnions 23, 23 disposed opposite to each other.
0 and 50 are set so that the arrangement of the oil chambers 50a and 50b is reversed to each other, and the trunnions 23 and 23 are driven in mutually opposite directions. The trunnions 23, 23 are connected via swingable links on the upper and lower sides of the pivot shaft 24, and the trunnions 23, 23 are displaced in opposite directions.

For this reason, in FIG. 2, if the oil pressure in the oil chamber 50a is decreased while the oil pressure in the oil chamber 50b is increased,
While the trunnion 23 on the left side in the figure rises, the trunnion 23 on the right side in the figure descends, and the power rollers 20 and 20 become L
The shift is performed by inclining (displacement about the axis of the trunnion 23) to the o side (the gear ratio _ic = large side).

One of the plurality of trunnions 23 includes an axial displacement amount of the trunnion 23 and a tilt angle of the power roller 20 (rotation angle of the trunnion 23 / actual transmission ratio).
Is provided to feed back to the shift control valve 56.

The precess cam 55 has a cam surface or a cam groove having a predetermined inclination in the circumferential direction, and the cam surface or the cam groove has a swingable feedback link 5.
4 (L link) is in sliding contact with one end.

The feedback link 54 is, for example, L
And is slidably supported at one end and slidably contacts the cam surface or the cam groove at one end, and the transmission link 53 at the other end.
(I link) and transmits the axial displacement and rotation of the trunnion 23, that is, the tilt angle of the power roller 20, to one end of the speed change link 53.

The transmission link 53 is connected to the spool 56S of the shift control valve 56 at substantially the center, while being connected to the feedback link 54.
The other end of the transmission 3 is connected to a step motor 52, and the speed change link 53 drives the step motor 52 to displace the spool 56S of the shift control valve 56 (speed control valve) in the axial direction. The spool 56S is displaced in the axial direction according to the directional displacement.

The shift control valve 56 has a supply port 56L to which the line pressure PL is supplied, and a port 56Lo communicating with the oil chamber 50b of the hydraulic cylinder 50.
w, a port 56Hi communicating with the oil chamber 50a of the hydraulic cylinder 50, and a pair of drain ports 56D, 56D with the supply port 56L interposed therebetween.

The spool 56S driven by the transmission link 53 connects the supply port 56L to the ports 56Hi, 56
It connects to one of the oil chambers 50a and 50b via Low, and connects the other oil chamber to the drain port 56D.

Thus, the spool 56 is moved in accordance with the displacement (drive amount) of the step motor 52 and the displacement of the precess cam 55.
The position of S is determined, the oil chambers 50a and 50b of the hydraulic cylinder 50 to which the line pressure PL is supplied are changed, and the hydraulic pressure is controlled so that the tilt angle is instructed by the step motor 52.

Next, FIG. 3 is a schematic configuration diagram of a control system including the mode switching control device 80.

A mode switching control device 80 mainly composed of a microcomputer has input torque from a torque sensor 88 attached to the unit input shaft 1, input speed of an IVT unit input shaft from a speed detection sensor 81, and sun gear. A rotation speed sensor 82 attached, an output shaft rotation speed from a rotation speed sensor 83 attached to a ring gear,
Carrier rotation speed from a rotation speed sensor 84 attached to the carrier, transmission torque from a torque sensor 86 attached to the power circulation clutch 9, transmission torque from a torque sensor 87 attached to the direct coupling clutch 10, throttle opening sensor The mode switching control unit 80 calculates the operation amount of each solenoid valve and step motor from these inputs, and sends the command values to the first solenoid valve 91 and the second solenoid valve 91. It outputs to the solenoid valve 92 and the step motor 52.

FIG. 4 is a block diagram of the mode switching control device 80.

The operating state detecting means 100 reads the values detected by the respective sensors shown in FIG.
Or inverse _i i of IVT gear ratio, CVT gear ratio i _c, the traveling load T _RL, sun gear rotational speed .omega.s, the ring gear rotational speed ω
r, IVT unit input shaft speed (= engine speed)
ωe, carrier rotation speed ωc, actual engine torque Te, steady engine torque Ts, power circulation clutch transmission torque T
_LC , direct coupling clutch transmission torque T _HC , throttle opening TV
O, and outputs the unit output shaft rotation speed _ωio .

The throttle opening TVO is a value detected by the throttle opening sensor 85.

The steady engine torque Ts is calculated from the unit input shaft rotation speed ωe and the throttle opening TVO using a map of engine characteristics (not shown).

The steady engine torque Ts is determined when the engine torque starts to change, that is, the unit input shaft rotation speed ωe
And the value after the end of the engine torque change when the throttle opening TVO changes.

As the actual engine torque Te, a value detected by the torque sensor 88 attached to the unit input shaft 1 is used, or an equation showing the dynamic characteristic of the engine torque with respect to the steady engine torque is obtained from the following equation (1). make use of,
It may be calculated from the steady engine torque Ts.

[0054]

(Equation 1) Here, Ce is a constant determined by the delay characteristic of the engine torque with respect to the throttle opening TVO and the engine speed ωe (here, the same value as the unit input shaft speed), which is determined from the characteristics of the engine.

The IVT output shaft speed ω _io is the speed ωr detected by the ring gear speed sensor 83.

Therefore, ω _io = ωr.

The IVT speed ratio i is the IVT output shaft speed ω
It is calculated from _io and the unit input shaft rotation speed ωe using the relationship shown in the following equation (2).

[0058]

(Equation 2) Moreover, reciprocal i _i of IVT gear ratio is calculated using the relationship shown in the following equation (3).

[0059]

(Equation 3) The CVT speed ratio _ic is calculated from the sun gear rotation speed ωs detected by the sun gear rotation speed sensor and the unit input shaft rotation speed ωe using the relationship shown in the following equation (4).

[0060]

(Equation 4) Here, id is the gear ratio of the constant reduction gear 3 on the CVT output side.

The sun gear rotation speed ωs is a value detected by the sun gear rotation speed detection sensor 82. The power-circulating clutch transmission torque _TLC is set to a value detected by a torque sensor 86 attached to the power-circulation clutch 9 or a power-circulation clutch transmission torque target value T ^* _LC , which is an output of clutch control means described later, is input. And Alternatively, an output of a low-pass filter that models the dynamic characteristics of the power circulation clutch 9 may be used.

The direct-coupled clutch transmission torque _THC is set to a value detected by a torque sensor 87 attached to the direct-coupled clutch 10 or a direct-coupled clutch transmission torque target value T ^* _HC , which is an output of clutch control means described later, is input. And Alternatively, the output of a low-pass filter that models the dynamic characteristics of the direct coupling clutch 10 may be used.

The running load T _RL is estimated from the vehicle speed VSP using a running load map (not shown).

[0064] The target value (target IVT speed ratio or its inverse) generator means 110, based on the throttle opening TVO and IVT output shaft rotation speed omega _io, obtains the arrival IVT gear ratio i _t, reaches IVT gear ratio i (target value for each control cycle) target IVT speed ratio i ^* from _t or calculating a reciprocal i ^* _i of the target IVT speed ratio.

[0065] In the clutch control unit 130, the constant engine torque Ts and CVT speed ratio i _c and the actual engine torque T
Configuration and reach IVT gear ratio i _t and e, based on the reciprocal i _i of IVT gear ratio i or IVT gear ratio, and a direct-coupled clutch transmission torque target value T ^* _HC and power circulation clutch transmission torque target value T ^* _LC I do.

In the CVT control means 120, the target IVT speed ratio i ^* or the reciprocal i ^* _i of the target IVT speed ratio, and IV
The reciprocal i _i of T gear ratio i or IVT gear ratio, CVT
Speed ratio i _c and the actual engine torque Te and the running load T _RL and the sun gear rotational speed .omega.s, a ring gear rotation speed .omega.r, and a power circulation clutch transmission torque T _LC or power circulation clutch transmission torque target value T ^* _LC, direct Clutch transmission torque T
_The step motor 52 is controlled according to the target CVT speed ratio i ^* _c or the target CVT speed di ^* _c / dt based on the _HC or the direct coupling clutch transmission torque target value T ^* _HC .

In the CVT speed ratio control means 140, the target C
VT gear ratio _ic ^* or target CVT gear speed di ^* _c / d
The step motor 52 is controlled according to t.

The power circulation clutch control means 141 controls the first solenoid valve 91 so that the power circulation clutch 9 generates a torque of the power circulation clutch transmission torque target value.
To control the hydraulic pressure of the first hydraulic servo 92.

The direct clutch control means 142 controls the current (or duty ratio) of the second solenoid valve 101 so that the direct clutch 10 generates the torque of the direct clutch transmission torque target value, and controls the second hydraulic servo 10.
2 is controlled.

FIG. 5 shows the mode switching control means 8 shown in FIG.
FIG. 4 is a diagram showing a more detailed configuration of a target value generation unit 110, a clutch control unit 130, and a CVT control unit 120 at 0.

The attained IVT speed ratio generating means 111 calculates the attained engine speed ω _te from the vehicle speed VSP and the throttle opening TVO, and obtains the attained IVT speed ratio from the attained engine speed ω _te and the IVT output shaft speed ω _io. to calculate the i _t.

First, the vehicle speed VSP and the throttle opening TVO
From this, the reached engine speed ω _te is determined using FIG. Here, the vehicle speed VSP using the following equation (5) showing the relationship between the IVT output shaft rotation speed omega _io and the vehicle speed VSP, IV
It is calculated from the T output shaft rotation speed _ωio .

VSP = κv × ω _io (5) Here, kv is a constant determined by the final gear ratio and the tire radius.

Next, to calculate the arrival IVT gear ratio i _t using the relationship shown by the arrival engine speed omega _te and IVT output shaft rotation speed omega _io the following equation (6).

[0075]

(Equation 5)In the target IVT gear ratio generation means 112, the reached IVT gear
Ratio i_tFrom, for example, the low-pass fill shown in the following equation (7)
Target IVT gear ratio i^*Is calculated or
Is the target IVT using the low-pass filter shown in equation (8).
Reciprocal of gear ratio i ^* _iIs the reciprocal of the reached IVT speed ratio it
It is calculated from Uti.

[0076]

(Equation 6) Here, cr and Cri are constants corresponding to a predetermined time constant determined by the seasoning of the shift.

In the shift direction determining means 131, for example, I
Inverse of VT gear ratio i or IVT gear ratio i _i and the arrival I
Enter the VT gear ratio i _t, in the case of using the IVT speed ratio i, the upshift when satisfying _{i <i t ......... (9)} , when using the inverse i _i of IVT gear ratio, i _i > Uti (10) An upshift is determined when the condition is satisfied, and a downshift is determined when the condition is not satisfied.

The target engine torque positive / negative determining means 132 determines whether the steady engine torque is positive or negative.

In the clutch torque target value generating means 133, first, the IVT calculated by the shift direction determining means 131 is obtained.
Gear shift direction and the engine torque positive / negative determination means 110
Based on the positive and negative of the steady engine torque obtained in the above, four shift modes are set as shown in Table 1 below.

In Table 1, in the shift mode, the negative torque upshift is a shift mode in which the steady engine torque is negative and the mode is switched with the mode shift, and the positive torque upshift is a mode switch in which the steady engine torque is positive. A positive torque downshift is a downshift shift mode in which the steady engine torque is positive and the mode is switched, and a negative torque downshift is a downshift shift mode in which the steady engine torque is a negative mode. Mode.

[0081]

[Table 1] Next, the order in which the torque phase and the inertia phase are performed is determined according to the following Table 2 according to the shift mode determined here.

[0082]

[Table 2] The time of the torque phase may be, for example, the minimum time t _tf required to perform the torque phase from the characteristics of the clutch.

Further, based on the CVT speed ratio _ic and the actual engine torque Te, the torque _TLC0 transmitted by the power circulating clutch 9 in the power circulating mode using the map shown in FIG.
Ask for. Similarly, from the CVT speed ratio _ic and the actual engine torque Te, the torque _THC0 transmitted by the direct coupling clutch in the direct coupling mode is determined using a map shown in FIG.

At this time, the relationship between the transmission torque T _LC0 and the power circulation clutch transmission torque target value T ^* _LC is expressed by the following (1).
The relationship between the transmission torque T _HC0 and the direct-coupled clutch transmission torque target value T ^* _HC is represented by expression (12).

[0085]

(Equation 7) Here, the time-varying coefficients i _LC and i _HC are obtained from the phase order and the time _{ttf of the} torque phase, for example, as shown in FIG.
Should be set as shown in the time chart of FIG.

In FIG. 10, (a) is a time chart of a negative torque upshift, (b) is a time chart of a positive torque upshift, (c) is a time chart of a positive torque downshift, and (d) is a time chart of a negative torque downshift. .

In the negative torque upshift shown in FIG. 10A, since the steady engine torque is in the negative engine braking state, the engine is about to be turned by the inertia of the vehicle. If the torque to be transmitted has not been reached, the slip of the clutch increases and the engine speed tends to decrease, and the IVT speed ratio, which is the ratio of the IVT input / output speeds, tends to increase (Hi side). I do.

Therefore, as set in Table 2, an inertia phase is performed first.

The inertia phase starts at time T0 as shown in FIG. In this inertia phase, by setting the time-varying coefficient i _LC to a value smaller than 1, the IVT speed ratio naturally moves toward the speed increasing side. Here, the coefficient i _LC during the inertia phase is, for example, 0.8
It is good to

At time Tc when the input / output rotation difference of the direct coupling clutch 10 becomes zero, the phase shifts from the inertia phase to the torque phase as set in Table 2.

This is because if the engagement of the direct coupling clutch 10 is started before the end of the inertia phase, the I
This is because the VT gear ratio tends to go to the speed increasing side, but in order to shift the gear to the direct connection mode, that is, to the gear increasing side of the IVT gear ratio, a sudden upshift causes a shift shock. .

In the torque phase, for example, the time-varying coefficient i
While decreasing _LC from 1 to 0 with a slope of -1 / _ttf with respect to time, the coefficient i _HC is reduced from 0 to 1 with a slope of 1 / t with time.
It is good to increase with _tf . This torque phase is performed at time T
The process ends at time T1 after time _ttf from c.

In the positive torque upshift shown in FIG. 10B, the steady engine torque is in the positive driving state, so that if the sum of the transmission torques of both clutches does not reach the torque to be transmitted, the slip of the clutch will not occur. The engine speed tends to increase, and the IVT speed ratio is reduced (Lo).
Side).

At this time, as in the case of the negative torque upshift, when the inertia phase is performed first, the coefficient i _LC
Is smaller than 1, the IVT speed ratio is downshifted against the demand for upshift, while if the coefficient i _LC is larger than 1, the input / output rotation difference of the power circulating clutch 9 is more likely to be kept at zero. I can't switch modes quickly while sliding.

Therefore, the torque phase is first performed as set in Table 2.

In the torque phase, for example, the coefficient i_LC1
From time to time -1 / t _tfOne to reduce by
, Coefficient i_HCSlope from 0 to 1 with respect to time 1 / t_tfGe
It is good to increase with. The torque phase starts at time T0
Time t_tfThe process ends at a later time Tc.

Then, after the time Tc, the inertia phase is performed, and the coefficient i _HC is set to be larger than 1, so that IV
Raise the T gear ratio to the speed increasing side. Here, the coefficient i _HC during the inertia phase may be set to, for example, 1.2.
The inertia phase ends at time T1 when the input / output rotation difference of the direct coupling clutch 10 becomes zero.

In the positive torque downshift shown in FIG. 10C, the steady engine torque is in the positive drive state, so that if the sum of the transmission torques of both clutches does not reach the torque to be transmitted, the slip of the clutch will not occur. As the engine speed increases, the engine speed tends to increase, and tends to go to the reduction side at the IVT speed ratio.

Therefore, the inertia phase is first performed as set in Table 2 for the same reason as the negative torque upshift (a).

The inertia phase starts at time T0 as shown in FIG. In this inertia phase, by setting the coefficient i _HC to a value smaller than 1, the IV
The T gear ratio is naturally turned to the deceleration side. Here, the coefficient i _HC during the inertia phase may be, for example, 0.8. Then, at time Tc when the input / output rotation difference of the power circulation clutch 9 becomes zero, the phase shifts from the inertia phase to the torque phase.

In the torque phase, for example, the coefficient i _{LC is set} to 0
From 1 to 1 while increasing the coefficient i _HC from 1 to 0 with a slope of 1 / t _tf with respect to time.
It is good to decrease by _tf . The torque phase is at time Tc
The processing ends at time T1 after time t _tf .

In the negative torque downshift shown in FIG. 10D, since the steady engine torque is negative (engine braking state), if the total transmission torque of both clutches does not reach the torque to be transmitted, Increases, the engine speed tends to decrease to idle speed, and the IVT speed ratio, which is the ratio of the IVT input / output speeds, tends to increase. At this time, when the inertia phase is first performed for the same reason as the positive torque upshift (b), if the coefficient i _HC is smaller than 1, the IVT speed ratio is upshifted against the demand of the downshift, while If the coefficient i _HC is larger than 1, the input / output rotation difference of the directly-coupled clutch will be kept at zero, so that it is not possible to perform fast mode switching while sliding the clutch.

Therefore, as set in Table 2, a torque phase is first performed.

In the torque phase, for example, the coefficient i _{LC is set} to 0
From 1 to 1 with a slope 1 / _ttf with respect to time,
Slope -1 / t with respect to time when the coefficient i _HC is changed from 1 to 0
It is good to decrease with _tf . Torque phase ends from the time T0 at the time Tc after the time t _tf.

Then, after the time Tc, the inertia phase is performed, and the coefficient i _LC is set to be larger than 1, thereby obtaining the IV.
Raise the T gear ratio to the speed increasing side. Here, the coefficient i _LC during the inertia phase is, for example, 1.2. The inertia phase ends at time T1 when the input / output rotation speed of the power circulation clutch becomes zero.

In the deviation calculating means 121 and the target IVT speed calculating means 122, the target IVT speed ratio i ^* or the reciprocal i ^* _i of the target IVT speed ratio and the IVT speed ratio i or I
Enter a reciprocal i _i of VT transmission ratio, the deviation e between the target IVT speed ratio i ^* and IVT gear ratio i in the following equation (13)
1 based on the following (1)
3 ′) or the target IV shown in the following equation (14)
T target IVT shift speed v2 based on a deviation e2 between the reciprocal i _i of the reciprocal i ^* _i and IVT transmission ratio of the transmission ratio, the following (1
4 ') It is calculated from the equation.

[0107]

(Equation 8) Here, c is a constant indicating the delay when the IVT speed ratio i responds with a first-order delay to the target IVT speed ratio i ^* , and ci is I with respect to the reciprocal i ^* _i of the target IVT speed ratio i ^* _i .
Inverse i _i of VT gear ratio is a constant that indicates the delay when a reply with first-order lag. As these constants c and ci increase, the delay decreases.

In the target CVT shift speed calculating means 123,
A target IVT travel and shift speed v1 or v2 and actual engine torque Te and the power circulation clutch transmission torque T _LC and the lockup clutch transmission torque T _HC and sun gear rotational speed ωs and the ring gear rotation speed ωr load T _RL, CVT speed ratio i _c And the target CVT shift speed di ^* _c / dt is set to the following (1).
5) Calculate as in the equation.

Also, the CVT speed ratio i_cInstead of
Target CVT calculated by the target CVT speed ratio calculating unit 124
Transmission ratio i_c ^*The power transmission clutch transmission torque
K T _LCInstead of the power circulation clutch transmission torque target value T
^* _LCTo the direct coupling clutch transmission torque T_LCInstead of
Latch transmission torque target value T^* _HCMay be used. Goal I
VT gear ratio i^*And the deviation based on the IVT gear ratio i
When the target IVT shift speed v1 is calculated as
The CVT speed is calculated by the following equation (15).

[0110]

(Equation 9) And the subscripts c and id and ig and I1 are IV
It is a constant determined from the structure of T. And the above d _LC , d
_HC , dRL, de, and dv1 are obtained in a practical IVT operating state.

[0111]

(Equation 10) Becomes

Also, the reciprocal i ^* _i of the target IVT gear ratio and IV
Target IVT shift speed v2 based on the inverse i _i T-gear ratio
Is calculated, the target CVT shift speed becomes the following (16)
It is calculated by the formula.

[0113]

[Equation 11] Here, this equation (16) is different from the above equation (15) and d
The difference is that v1 becomes dv2, which is represented by the following equation.

[0114]

(Equation 12) And, this dv2 is a practical IVT operating state,

[0115]

(Equation 13) Becomes

[0116] The _{above, dv1, d LC, d HC} , de, dR
L, the positive and negative dv2, as described later, the power circulation clutch transmission torque T _LC and the lockup clutch transmission torque T _LC and the actual engine torque Te and the target IVT shift speed v1 or v
How to move the target CVT shift speed di ^* _c / dt in accordance with the second variation is determined.

As described above, the signs of d _LC , d _HC , de, dv1, and dv2 are fixed in the practical operation state of IVT, and therefore, for example, d _LC , d _HC , de _HC in the operation state of IVT mode switching. , Dv1 and dv2 are represented by d
_LC, by setting a constant as d _HC, de, dv1, dv2, it is possible to approximate the response of the IVT transmission ratio i for the target IVT speed ratio i ^* in response a certain time constant, the computational load becomes lighter. However, as described above, d _LC ,
When d _HC , de, dv1, and dv2 are corrected using the CVT speed ratio _ic , the sun gear speed ωs, and the ring gear speed ωr, the response of the IVT speed ratio i to the target IVT speed ratio i ^* is more accurate. Since it is possible to approach a response with a constant time constant, for example, it is preferable to determine whether or not to perform the correction based on the performance of the microcomputer of the control device and the demand for the shift accuracy.

The target CVT speed ratio calculating section 124 calculates the target CVT
The target CVT speed ratio i ^* _c is calculated by integrating the VT speed di ^* _c / dt. When the step motor 52 is controlled according to the target CVT shift speed, in FIG.
The calculation unit 124 is not required, and has a configuration as shown in FIG.

By the above operation, the dynamic characteristic of the IVT gear ratio or the reciprocal of the IVT gear ratio with respect to the target IVT gear speed has a first-order integral relationship, and the equation for calculating the deviation and the target IVT gear speed is expressed by the following equation (13). Together with the equation (13 ′) or the equations (14) and (14 ′), the IVT speed ratio i relative to the target IVT speed ratio i ^* or the target IVT speed ratio i ^*
The dynamic characteristics of the inverse i _i of IVT gear ratio reciprocal i ^* _i of the gear ratio may be a first-order lag characteristic of the time constant 1 / c.

Next, an example of the shift control performed by the mode switching control device 80 will be described in detail with reference to flowcharts shown in FIGS. In the following flowchart, a case is shown in which the target IVT shift speed for compensating for the deviation is calculated based on the difference between the target IVT speed ratio and the IVT speed ratio. This mode switching control process is executed at a predetermined control cycle, for example, every 10 ms. FIG. 11 is a flowchart of the main routine.

In step S1, each value of the sensor shown in FIG. 3 is read.

In step S2, the attained engine speed ω _te is obtained from the vehicle speed VSP and the throttle opening TVO by using the shift map shown in FIG. 7, and by using the above equation (6).
From the arrival engine speed omega _te and IVT output shaft rotation speed omega _io, calculates an arrival IVT gear ratio i _t.

In step S3, the target IVT shift speed di ^* is calculated by the following equation (17) obtained by discretizing the equation (7), and further, the target IVT shift speed di ^* is calculated by using the equation (18).
^The target IVT speed ratio i ^* is calculated by integrating ^* .

[0124]

[Equation 14] Here, n indicates the current sample value, and (n-1) indicates the previous value. In addition, T is a sample period. Here, since the sample period is set to 10 ms, T = 0.01.

In step S4, the IVT speed ratio i is set to I
It is calculated from the VT output shaft rotation speed _ωio and the unit input shaft rotation speed ωe using the relationship shown in the above equation (2).

At step S5, the CVT speed ratio _ic is _calculated as
It is calculated from the sun gear rotation speed ωs and the unit input shaft rotation speed ωe using the relationship shown in the above equation (4).

In step S6, the steady engine torque 4
With the rotation speed ωe of the unit input shaft and the throttle opening TV
From O, it is calculated using an engine characteristic map (not shown).

In step S100, a mode switching control subroutine described later is executed.

FIG. 12 is a flowchart of the mode switching control subroutine.

In step S101, the mode switching control flag Fmc is referred to. If Fmc = 1, the mode is being switched, and the flow advances to step S200 to execute the clutch control subroutine in step S200 and the mode switching end determination subroutine in step S300. Then, the process proceeds to step S400.

On the other hand, if Fmc = 0, the mode is not a mode switch, and the process proceeds to step S102.

[0132] In step S102, obtains the operation mode in reaching IVT gear ratio i _t.

[0133] That is, reach IVT gear ratio i _t is, if a speed-increasing side of the IVT speed ratio i _r in the rotation synchronous point RSP, the TMODE = 1 indicating a direct connection mode, reaches IVT gear ratio i _t is rotated IVT at the synchronization point RSP
If the gear ratio i _{r is} on the deceleration side, tmode = 0 indicating the power circulation mode is set.

In step S103, the mode is determined based on the current operation mode mode and the attainment operation mode tmode.
If it is not ≠ tmode, it is determined that the mode switching has been requested, the mode switching control flag Fmc is set to 1 in step S104, the mode switching control preparation subroutine in step S500 is executed, and then the process proceeds to step S105. On the other hand, if mode = tmode, it is determined that no mode switching has been requested, and the process proceeds to step S105.

In step S105, referring to the current operation mode mode, if tmode = 0, the operation is in the power circulation mode.
If mode = 1, the mode is the direct connection mode, so the flow proceeds to step S107 to set the clutch hydraulic pressure command value, and then proceeds to step S400.

In step S106, in order to establish the power circulation mode, the power circulation clutch oil pressure command value pressure _PLC
And the direct-coupled clutch hydraulic pressure command value P _HC are set as follows.

P _LC = P _MAX P _HC = 0 Here, P _MAX is the maximum hydraulic pressure supplied to the clutch, and is set to, for example, the same value as the line pressure.

In step S107, in order to establish the direct connection mode, the power circulation clutch oil pressure command value _PLC and the direct connection clutch oil pressure command value _PHC are set as follows.

[0139] Then _{P LC = 0 P HC = P} MAX, at step S400, by executing the CVT speed ratio control subroutine, exits the mode switching control subroutine.

FIG. 13 is a flowchart of a mode switching preparation subroutine.

In step S501 of FIG. 13, reference is made to the current operation mode mode. If mode = 1, the current mode is the direct connection mode. If the mode = 0, the process proceeds to step S502. Mode, step S for setting upshift.
Proceed to 505.

In step S502, it is determined whether the steady engine torque Ts is positive or negative. If Ts <0, it is determined that a negative torque downshift is performed, and the process proceeds to step S503. If not, a positive torque downshift is performed.
Proceed to 4.

In step S503, a variable pat indicating a shift pattern is set to 0 indicating a negative torque downshift. In the negative torque downshift, Ff is set to 0 because the torque phase is performed first.

In step S504, a variable pat indicating a shift pattern is set to 1 indicating a positive torque downshift. In the positive torque downshift, Ff is set to 1 since an inertia phase is performed first.

In step S505, it is determined whether the steady engine torque Ts is positive or negative. If Ts <0, it is determined that a negative torque upshift is performed, and the process proceeds to step S506.
Go to 7.

In step S506, the variable pat indicating the shift pattern is set to 2 indicating a negative torque upshift, and in the negative torque upshift, Ff is set to 1 since the inertia phase is performed first.

In step S507, the variable pat indicating the shift pattern is set to 3 indicating the positive torque upshift, and in the positive torque upshift, the torque phase is performed first, so that Ff is set to 0.

In step S508, the timer count t for managing the torque phase is reset to 0, and the process exits the subroutine.

FIG. 14 is a flowchart of a clutch control subroutine.

In step S201 in FIG. 14, the torque _TLC0 transmitted by the power circulation clutch 9 in the power circulation mode is obtained from the CVT speed ratio _ic and the actual engine torque Te using the map shown in FIG. .

In step S202, the CVT speed ratio _ic
Using the map shown in FIG. 9, the torque _THC0 transmitted by the direct coupling clutch 10 in the direct coupling mode is obtained from the actual engine torque Te.

In step S203, the input / output rotational speed difference d _LC of the power circulating clutch 9 is _converted to the unit input shaft rotational speed ωe.
And the carrier rotation speed ωc, using the following equation (19).

[0153]

(Equation 15) In step S204, the input / output rotational speed difference d _HC of the direct coupling clutch 9 is determined by comparing the sun gear rotational speed ωs and the ring gear rotational speed ωc.
Is calculated from the following equation (20).

[0154]

(Equation 16) In steps S205 to S207, the shift pattern is determined from the variable pat. If the shift is a negative torque downshift, the negative torque downshift control subroutine is executed in a step S600.
0 executes the positive torque downshift control subroutine,
Run the negative torque upshift control subroutine at step S620 if the negative torque upshift, perform a positive torque upshift control subroutine at step S630 if the positive torque upshift, sets the i _LC and i _HC.

In step S208, the power circulating clutch
Transmission torque target value T^* _LCAnd the T_{L C0}And i_LCAnd from above
Calculated by equation (11), the direct-coupled clutch transmission torque target value T
^* _HC, The T_HC0And i_HCFrom the above equation (12).
You.

In step S209, the target value T ^* _{LC of} the power-circulating clutch transmission torque is calculated using the following equation (21).
Calculating the power recirculation clutch oil pressure command value P _LC modes being switched.

[0157]

[Equation 17] Here, kP _LC is a constant determined from the structure and friction coefficient of the power circulation clutch 9.

Also, the direct coupling clutch transmission torque target value T ^*
Using the following equation (22) from the _HC, calculates a lockup clutch oil pressure command value P _HC modes being switched.

[0159]

(Equation 18) Here, kP _HC is a constant determined from the structure of the direct coupling clutch 10 and the friction coefficient.

In step S210, the timer counter t for managing the torque phase is counted up, and the process exits from the subroutine.

FIG. 15A is a flowchart of a negative torque downshift control subroutine.

In FIG. 15A, step S6
In the case of 01, referring to the flag Ff, if Ff = 0 and the torque phase, the process proceeds to step S602; otherwise, the process proceeds to step S603.

In step S602, i _LC and i _HC in the torque phase are set as follows, and in step S604
Proceed to.

[0164]

[Equation 19] Here, tf is the time required for the torque phase.

In step S603, i _LC and i _HC in the inertia phase are set as follows, and the process exits from the subroutine.

[0166] In the i _LC = 1.2 i _HC = 0 step S604, is compared with the time counter t and t _tf, if t> t _tf, in step S605, the transition to the inertia phase make a 1 to Ff And exit the subroutine.

FIG. 15B is a flowchart of a positive torque downshift control subroutine.

Referring to FIG. 15B. Step S6
In step 11, with reference to the flag Ff, if Ff = 0 and the torque phase, the process proceeds to step S612; otherwise, the process proceeds to step S615.

In step S612, i _LC and i _HC in the torque phase are set as follows, and in step S613
Proceed to.

[0170]

(Equation 20) In step S613, by comparing the time counter t and t _tf, if the torque phase at t> t _tf has been completed, step S6
At 14, i _LC and i _HC are held at i _LC = 1 i _HC = 0, and the subroutine is exited.

In step S615, i _LC and i _HC in the inertia phase are set as follows, and in step S6
Proceed to 16.

I _LC = 0 i _HC = 0.8 In step S616, it is determined whether or not the input / output rotation difference d _LC of the power circulating clutch 9 is zero and the inertia phase has ended. If it is zero, Ff = in step S617. The flow shifts to the torque phase as 0, the timer counter t is reset to zero in step S618, and the process exits the subroutine.

FIG. 16A is a flowchart of the negative torque upshift control subroutine.

In FIG. 16A, step S621 is performed.
Then, referring to the flag Ff, if Ff = 0 and the torque phase, the process proceeds to step S622; otherwise, the process proceeds to step S625.

In step S622, i _LC and i _HC in the torque phase are set as follows, and in step S623
Proceed to.

[0176]

(Equation 21) In step S623, by comparing the time counter t and t _tf, if the torque phase at t> t _tf has been completed, step S6
At 24, i _LC and i _HC are held at i _LC = 0 i _HC = 1, and the subroutine is exited.

At step S625, i _LC and i _HC in the inertia phase are set as follows, and at step S6
Proceed to 26.

I _LC = 0.8 i _HC = 0 In step S626, it is determined whether the input / output rotation difference d _HC of the direct coupling clutch 10 is zero and the inertia phase has ended. If it is zero, Ff = 0 in step S627. Then, in the torque phase, the timer counter t is reset to zero in step S628, and the subroutine is exited.

FIG. 15B is a flowchart of a positive torque upshift control subroutine.

In step S631 of FIG. 15B, referring to the flag Ff, if Ff = 0 and the torque phase, the process proceeds to step S632; otherwise, the process proceeds to step S6.
Go to 33. In step S632, i _LC and i _HC in the torque phase are set as follows, and step S634
Proceed to.

[0181]

(Equation 22) In step S633, i _LC and i _HC in the inertia phase are set as follows, and the process exits the subroutine.

[0182] In the i _LC = 0 i _HC = 1.2 step S634, is compared with the time counter t and t _tf, t> in t _tf If the step S635, the process proceeds to the inertia phase make a 1 to Ff To exit the subroutine.

FIG. 17 is a flowchart of the CVT speed ratio control subroutine.

First, in step S401, the above (1)
The target IVT speed ratio i ^* and the IVT speed ratio deviation e1 are calculated using the expression 3).

Next, in step S401 ', the target IV
It is calculated from the T shift speed v1 and the IVT speed ratio i using the above equation (13 ').

In step S402, the target CVT shift speed di ^* _c / dt is calculated using the above equation (15).

In step S403, the target CVT speed ratio i ^* _c is calculated using the following equation, and the process exits the subroutine.

[0188]

(Equation 23) FIG. 18 is a flowchart of the mode switching end determination subroutine.

In FIG. 18, in step S301,
It is determined whether the upshift or the downshift is performed by referring to the variable pat representing the shift pattern. If the variable pat is 2 or 3 and the upshift is performed, the process proceeds to step S302 to determine the end of the upshift.
Proceeding to 305, the end of the downshift is determined.

In step S302, it is determined whether or not the input / output rotation difference d _HC of the direct coupling clutch is zero.
At 3, it is determined whether the power circulation clutch oil pressure command value _PLC is zero, and if both are satisfied, the mode is set to 1 of the direct connection mode at step S304, and step S308 is performed.
Otherwise, exit the subroutine.

In step S305, it is determined whether or not the input / output rotation difference d _LC of the power circulating clutch is zero.
At 306, it is determined whether the direct-coupled clutch hydraulic pressure command value _PHC is zero, and if both are satisfied, the mode is set to 0 of the power circulation mode at step S307, and at step S3
08, otherwise exit the subroutine.

In step S308, the mode switching flag Fmc is designed to be zero, the mode switching is completed, and the process exits the subroutine.

FIG. 19 shows an example of shifting in the case of shifting from mode (a) to mode (b) in FIG. 21 with mode switching.

FIG. 19 shows an example of a positive torque upshift. From FIG. 18, it can be seen from FIG.
The output shaft torque and the IVT gear ratio change smoothly without stopping at SP.

As described above, according to the present invention, the order of the phases of the torque phase and the inertia phase is determined based on the change pattern of the IVT speed ratio and the positive / negative of the steady engine torque, based on the preset operation mode switching pattern. Since the power transmission clutch target torque and the direct coupling clutch target torque are set in a predetermined pattern, they are set based on the phase order, the actual engine torque, and the CVT speed ratio. Target IVT speed v1 for compensating deviation
Is calculated based on the deviation between the target IVT gear ratio and the IVT gear ratio, or the deviation between the reciprocal of the target IVT gear ratio and the reciprocal of the IVT gear ratio. Then, the target CVT shift speed is calculated from the deviation, the power circulation clutch transmission torque target value, the direct coupling clutch transmission torque target value, and the engine torque. As shown in Table 3 below, the target CVT shift speed is increased or decreased according to changes in the power circulation clutch transmission torque target value, the direct coupling clutch transmission torque target value, and the engine torque.

[0196]

[Table 3] Then, in the mode switching, the target IVT gear ratio and the IVT
When compensating for the deviation from the speed ratio, the target CVT speed is adjusted in accordance with changes in the target IVT speed, clutch transmission torque and engine torque based on the deviation between the target IVT speed ratio and the IVT speed ratio while sliding the clutch. , The deviation between the target IVT gear ratio and the IVT gear ratio can be corrected by the CVT without giving a target value based on a number of experiments and simulations, without increasing the development time and development cost. The shift can be performed while suppressing the shift shock.

In consideration of the fact that the sensitivity when the power circulation clutch transmission torque, the direct coupling clutch transmission torque, the engine torque and the CVT speed change affect the IVT speed changes in accordance with the CVT speed ratio, the target The coefficient multiplied by the power circulation clutch transmission torque target value, the coefficient multiplied by the direct coupling clutch transmission torque target value, the coefficient multiplied by the engine torque, and the coefficient multiplied by the target IVT shift speed during the calculation of the CVT shift speed are calculated as target values. Since the correction is made according to the target CVT gear ratio obtained by integrating the CVT gear speed or the CVT gear ratio detected by the CVT gear ratio detecting means, the CV gear ratio is corrected.
Since the target CVT shift speed adapted to the sensitivity that changes according to the T gear ratio is calculated, and the mode switching can be performed while the IVT operation state is more reliably considered, the target IVT is selected.
The response of the IVT speed ratio to the speed ratio becomes closer to the desired characteristics, and the occurrence of the speed change shock can be reliably suppressed.

Further, the sensitivity when the power circulation clutch transmission torque, the direct coupling clutch transmission torque, the engine torque, and the CVT speed change the IVT speed changes in accordance with the sun gear speed and the ring gear speed. In consideration of the above, the coefficient multiplied by the target value of the power circulation clutch transmission torque, the coefficient multiplied by the target value of the direct coupling clutch transmission torque, the coefficient multiplied by the engine torque, and the target IVT speed are calculated when calculating the target CVT shift speed. The coefficient is corrected according to the rotation speeds of the ring gear and the sun gear, so that a target CVT speed change speed adapted to the sensitivity that changes according to the sun gear rotation speed and the ring gear rotation speed is calculated, and the operating state of the IVT is improved. Since the mode switching can be performed while reliably taking into account, the response of the IVT speed ratio to the target IVT speed ratio is closer to the desired characteristics. Now, it is possible to reliably suppress the occurrence of shift shock.

The target CVT speed is set to the target IVT speed.
When the target IVT speed is calculated based on the difference between the target IVT speed ratio and the IVT speed ratio, the target CVT speed is increased or decreased as shown in the following table.

[0200]

[Table 4] When the target IVT speed is calculated based on the difference between the reciprocal of the target IVT speed ratio and the reciprocal of the IVT speed ratio, the target CVT speed is increased or decreased as shown in the following table.

[0201]

[Table 5] Furthermore, since the target CVT shift speed is calculated based on the running load, control according to the change in the running load due to the influence of the road gradient or road surface condition can be performed, and even in a situation where the running load changes on an uphill road or the like. Smooth mode switching becomes possible.

In the above embodiment, the throttle opening may be used instead of the throttle opening.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a continuously variable transmission with an infinite gear ratio showing an embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a transmission mechanism of the toroidal type continuously variable transmission.

FIG. 3 is a schematic configuration diagram showing a control system of a continuously variable transmission with an infinite speed ratio.

FIG. 4 is a conceptual diagram of a mode switching control device.

FIG. 5 is a conceptual diagram of a clutch control unit and a CVT control unit.

FIG. 6 is a conceptual diagram showing another example of the clutch control means and the CVT control means.

FIG. 7 is a map of a reached engine speed corresponding to a vehicle speed and a throttle opening.

FIG. 8 is a power circulation clutch transmission torque map according to the CVT speed ratio and the engine torque in the power circulation mode.

FIG. 9 is a direct-coupled clutch transmission torque map according to the CVT speed ratio and the engine torque in the direct-coupled mode.

FIG. 10 is a time chart for each shift pattern of the time-varying coefficients i _LC and i _HC , where (a) shows a negative torque upshift;
(B) shows a positive torque upshift, (c) shows a positive torque downshift, and (d) shows a negative torque downshift.

FIG. 11 is a flowchart illustrating a main routine of mode switching control.

FIG. 12 is a flowchart of a mode switching control subroutine.

FIG. 13 is a flowchart of a mode switching preparation subroutine.

FIG. 14 is a flowchart of a clutch control subroutine.

15A is a flowchart of a negative torque downshift control subroutine, and FIG. 15B is a positive torque downshift control subroutine.

16A is a flowchart of a negative torque upshift control subroutine, and FIG. 16B is a flowchart of a positive torque upshift control subroutine.

FIG. 17 is a flowchart of a CVT speed ratio control subroutine.

FIG. 18 is a flowchart of a mode switching end determination subroutine.

FIG. 19 is a time chart showing an example of a positive torque upshift, in which an IVT speed ratio, a deviation, a clutch transmission torque,
The relationship between engine torque, CVT speed, CVT speed ratio, output shaft torque and time is shown.

C of FIG. 20 IVT gear ratio of the reciprocal i _i and the continuously variable transmission mechanism
4 is a map showing a relationship of a VT gear ratio _ic .

[21] Also, the map showing the relationship between the CVT speed ratio i _c of reciprocal i _i and the continuously variable transmission mechanism of IVT gear ratio, showing the state of mode switching.

[Explanation of symbols]

 Reference Signs List 1 unit input shaft 2 stepless speed change mechanism 3 constant speed change mechanism 5 planetary gear mechanism 9 power circulating clutch 10 direct coupling clutch 52 step motor 80 mode switching control device 81 input shaft speed sensor 82 sun gear speed sensor 83 unit output shaft speed sensor 84 Carrier speed sensor 85 Throttle opening sensor 87 Output shaft speed sensor 91 First solenoid 92 Second solenoid

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J552 MA09 MA13 MA30 NB01 PA02 RA18 TA10 TB18 VA34W VA74W VB09W VC01W VC02W VC03W

Claims (4)

[Claims] 1. A continuously variable transmission mechanism capable of continuously changing a gear ratio and a constant transmission mechanism are respectively connected to a unit input shaft, and an output shaft of the continuously variable transmission mechanism and the constant transmission mechanism are connected to a planetary gear mechanism and a power source. An infinitely variable speed ratio continuously variable transmission connected to a unit output shaft via a circulating clutch and a direct coupling clutch, and the power circulation clutch is engaged, and the direct coupling clutch is released to transmit power including an infinite total transmission ratio. Speed change ratio infinitely variable speed changeover comprising a power circulating mode, and a mode switching control means for switching between a direct coupling mode in which a direct coupling clutch is engaged, a power circulating clutch is released, and power is transmitted according to a continuously variable transmission mechanism. A CVT speed ratio detecting means for detecting a speed ratio of the continuously variable transmission mechanism, and an IV for detecting a total speed ratio of the infinitely variable speed transmission.
T gear ratio detection means, IVT output shaft rotation number detection means for detecting the rotation number of the unit output shaft, throttle opening degree detection means for detecting the throttle opening degree, from the output shaft rotation number and the throttle opening degree. Reaching IVT speed ratio generating means for calculating a reaching total speed ratio, target IVT speed ratio generating means for calculating a target total speed ratio based on the reaching total speed ratio, the detected total speed ratio and target total speed ratio Speed change direction determining means for determining the direction of change of the total gear ratio, actual engine torque detecting means for detecting or estimating the actual engine torque, and steady state estimating the value of the engine torque after the end of the change when the engine torque starts to change Engine torque estimating means; steady engine torque positive / negative determining means for determining whether the steady engine torque is positive or negative; A torque phase that increases the absolute value of the transmission torque on the engaged side of the power circulating clutch and the direct coupling clutch based on the positive and negative of the torque; Phase order setting means for setting which phase to start from among the inertia phases that are changed so that the input / output rotational speeds of the stepless transmission mechanism are equal to each other; Clutch torque target value generation means for calculating a target value of the transmission torque of the power circulating clutch and the direct coupling clutch based on the phase; and calculating a target gear speed of a total gear ratio from the detected total gear ratio and the target gear ratio. Target IVT shift speed calculating means, the actual engine torque, the target value of the clutch transmission torque, and the total speed ratio Based on the target shift speed, the shift control device of the IVT, characterized in that a target CVT shift speed calculating means for calculating a target shift speed of the continuously variable transmission mechanism. 2. The target CVT shift speed calculating means multiplies a coefficient multiplied by a transfer torque target value of the power circulating clutch and a transfer torque target value of the direct coupling clutch when calculating a target shift speed of the continuously variable transmission mechanism. And a coefficient multiplied by the actual engine torque and a coefficient multiplied by the target gear speed of the total gear ratio are obtained by integrating the target gear speed of the continuously variable transmission mechanism or the detected continuously variable gear ratio. The shift control device for an infinitely variable speed ratio transmission according to claim 1, wherein the correction is performed according to the speed ratio of the speed change mechanism. 3. The target CVT shift speed calculating means includes a rotation speed detecting unit for detecting a sun gear rotation speed and a ring gear rotation speed of the planetary gear mechanism, and calculates a target shift speed of the continuously variable transmission mechanism. In this case, the coefficient multiplied by the target value of the transmission torque of the power circulation clutch, the coefficient multiplied by the target value of the transmission torque of the direct coupling clutch, the coefficient multiplied by the actual engine torque, and the detected values of the sun gear rotation speed and the ring gear rotation speed The shift control device for a continuously variable transmission with an infinite speed ratio according to claim 1 or 2, wherein the shift is corrected according to the following. 4. The target CVT speed change calculating means includes a running load detecting means for detecting a running load, and calculates the target CVT speed based on a detected value of the running load. The shift control device for a continuously variable transmission with an infinite speed ratio according to any one of claims 1 to 3.