WO2020110658A1 - Control device and control method for continuously variable transmission - Google Patents

Abstract

This control device for a belt-type continuously variable transmission (CVT) has: a drum rotation sensor (96) that detects the rotation of a drum member (33) of a forward/reverse switching mechanism (3); a primary rotation sensor (90) that detects the rotation of a primary rotary shaft (40); and a turbine rotation estimation unit (80) that calculates the turbine estimation value (NTBN') of a turbine rotary shaft (21) on the basis of the detection value of the drum rotation sensor (96) and the primary rotation sensor (90). When the detection value of the drum rotation sensor (96) and the detection value of the primary rotation sensor (90) are unclear, the turbine rotation estimation unit (80) estimates the rotation speed of the unclear detection value by using at least two among the traveling/stop state, the fastened/released states of a forward clutch (31) and a reverse brake (32), and the transmission ratio of a variator (4), and calculates the turbine rotation estimation value (NTBN') by using the estimated rotation estimation value and the detection value of the other sensor.

Description

Control device and control method for continuously variable transmission

The present invention relates to a control device and a control method for a continuously variable transmission mounted on a vehicle.

Conventionally, there is known a power train control device capable of estimating and calculating an input rotation speed and continuing control even if a turbine sensor of an automatic transmission fails (for example, refer to Patent Document 1). This conventional device normally performs high-precision shift control and line pressure control using the turbine sensor, and estimates and calculates the turbine speed using input information other than the turbine sensor when the turbine sensor fails. When the gear is not being changed, the input speed of the automatic transmission is calculated from the vehicle speed signal and the gear ratio. When the gear is being changed, the input torque (pump torque) of the torque converter is obtained by using the engine torque map characteristic, and the input torque of the automatic transmission and the input speed of the automatic transmission are estimated and obtained. Here, at the start of gear shifting, the accessory torque value is learned to correct the accessory torque, and the torque due to the inertia moment of the engine is corrected to improve the accuracy of the input speed of the automatic transmission and the input torque of the automatic transmission. Make an estimate.

However, depending on the layout of the belt type continuously variable transmission, the turbine rotation sensor is not attached, the drum rotation sensor is provided on the drum of the forward/reverse switching mechanism, and the turbine is detected based on the detection values of the drum rotation sensor and the primary pulley rotation sensor. May estimate the rotation speed of. In such a belt-type continuously variable transmission, if the primary rotation speed is unknown, the gear ratio is also unknown. Therefore, the primary rotation speed cannot be estimated based on the gear ratio, and the turbine rotation speed cannot be estimated.

The present invention aims to ensure acquisition of turbine rotation information by estimation when the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown.

Japanese Patent Laid-Open No. 9-2106

The present invention includes a torque converter, a forward/reverse switching mechanism, a continuously variable transmission mechanism, and a transmission controller, and the transmission controller executes control using turbine speed information input to the forward/reverse switching mechanism. A control device for a continuously variable transmission, comprising:
A turbine rotation shaft that connects the turbine runner of the torque converter and the sun gear of the planetary gear,
A planetary gear carrier and a ring gear connected through a forward clutch,
A drum rotation sensor for detecting the number of rotations of the drum member connected to the ring gear,
A primary rotation sensor that detects the rotation speed of a primary rotation shaft that connects the carrier of the planetary gear and the primary pulley,
Turbine rotation estimating means for calculating a turbine rotation estimated value of the turbine rotation shaft based on the detection values of the drum rotation sensor and the primary rotation sensor,
Turbine rotation estimation means, when the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown, the running/stopped state, the engagement/release state of the forward clutch and reverse brake, the gear ratio of the continuously variable transmission mechanism, At least two are used to estimate the rotational speed of the unknown detection value, and the turbine rotation estimation value is calculated by the estimated rotation estimation value and the other sensor detection value.

Therefore, if the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown, it is possible to ensure acquisition of turbine rotation information by estimation.

FIG. 1 is an overall system diagram showing a drive system and a control system of an engine vehicle to which a control device for a continuously variable transmission according to an embodiment is applied. FIG. 9 is a shift schedule diagram showing an example of a D range continuously variable shift schedule used when the continuously variable shift control in the automatic shift mode is executed by the variator. It is a schematic block diagram which shows the control apparatus of the Example in which control using turbine rotation speed information is performed in a CVT control unit. It is a flowchart which shows the flow of a turbine rotation estimated value calculation process performed by the turbine rotation estimation part of a CVT control unit. FIG. 7 is a collinear diagram of the forward/reverse switching mechanism showing a scene in which the abnormality determination of the drum rotation sensor and the primary rotation sensor is prohibited. It is a figure showing a planetary gear, a forward clutch, a reverse brake, a turbine rotation sensor, and a primary rotation sensor in a forward/reverse switching mechanism of a comparative example. FIG. 7 is a collinear diagram of a forward/reverse switching mechanism showing a calculation process of a turbine rotation estimated value when both the detection value of the drum rotation sensor and the detection value of the primary rotation sensor can be used. FIG. 7 is a collinear diagram of a forward/reverse switching mechanism showing a calculation process of a turbine rotation estimated value when the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown during engagement traveling of the forward clutch (FWD/C). .. FIG. 6 is a collinear diagram of a forward/reverse switching mechanism showing a calculation process of a turbine rotation estimated value when the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown during engagement travel of the reverse brake (REV/B). .. Forward clutch (FWD/C) and reverse brake (REV/B) are disengaged. During forward/backward, the turbine rotation estimated value calculation process is performed when the drum rotation sensor detection value or primary rotation sensor detection value is unknown. It is an alignment chart of a switching mechanism. FIG. 6 is a collinear diagram of a forward/reverse switching mechanism showing a calculation process of a turbine rotation estimated value when the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown while the forward clutch (FWD/C) is engaged and stopped. .. FIG. 6 is a collinear diagram of a forward/reverse switching mechanism showing a calculation process of a turbine rotation estimated value when the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown while the reverse brake (REV/B) is engaged and stopped. .. Forward clutch (FWD/C) and reverse brake (REV/B) are disengaged. While the vehicle is stopped, the turbine rotation estimated value calculation process when the drum rotation sensor detection value or the primary rotation sensor detection value is unknown is indicated. It is an alignment chart of a switching mechanism.

Hereinafter, a mode for carrying out a control device for a continuously variable transmission according to the present invention will be described based on an embodiment shown in the drawings.

The control device in the embodiment is applied to a small engine vehicle equipped with a belt type continuously variable transmission including a torque converter, a forward/reverse switching mechanism, a variator, and a final reduction mechanism. Hereinafter, the configuration of the embodiment will be described by being divided into an "overall system configuration", a "control device configuration", and a "turbine rotation estimated value calculation processing configuration".

[Overall system configuration]
FIG. 1 shows a drive system and a control system of an engine vehicle to which a control device for a continuously variable transmission according to an embodiment is applied. The overall system configuration will be described below with reference to FIG.

As shown in FIG. 1, a drive system of an engine vehicle includes an engine 1, a torque converter 2, a forward/reverse switching mechanism 3, a variator 4, a final reduction mechanism 5, and drive wheels 6 and 6. There is. Here, the belt type continuously variable transmission CVT is configured by incorporating a torque converter 2, a forward/reverse switching mechanism 3, a variator 4, and a final reduction mechanism 5 in a transmission case (not shown).

The engine 1 can control the output torque by an engine control signal from the outside, in addition to the control of the output torque by the accelerator operation by the driver. The engine 1 has an output torque control actuator 10 that controls torque by opening/closing a throttle valve, cutting fuel, or the like. For example, the fuel cut control is executed during coast running by the accelerator foot release operation.

The torque converter 2 is a starting element with a fluid coupling having a torque amplification function and a torque fluctuation absorption function. When the torque amplification function and the torque fluctuation absorption function are not required, the engine output shaft 11 (=torque converter input shaft) and the turbine rotation shaft 21 (=torque converter output shaft) 21 have a lockup clutch 20 that can be directly connected. The torque converter 2 includes a pump impeller 23, a turbine runner 24, and a stator 26 as constituent elements. The pump impeller 23 is connected to the engine output shaft 11 via the converter housing 22. The turbine runner 24 is connected to the turbine rotating shaft 21. The stator 26 is provided in the transmission case via the one-way clutch 25.

The forward/reverse switching mechanism 3 is a mechanism that switches the input rotation direction to the variator 4 between the forward rotation direction when traveling forward and the reverse rotation direction when traveling backward. The forward/reverse switching mechanism 3 includes a double pinion type planetary gear 30, a forward clutch 31 including a plurality of clutch plates, and a reverse brake 32 including a plurality of brake plates. The forward clutch 31 is hydraulically engaged by the forward clutch pressure Pfc when the forward traveling range such as the D range is selected. The reverse brake 32 is hydraulically engaged by the reverse brake pressure Prb when the reverse traveling range such as the R range is selected. The forward clutch 31 and the reverse brake 32 are both released by draining the forward clutch pressure Pfc and the reverse brake pressure Prb when the N range (neutral range) is selected.

The variator 4 includes a primary pulley 42, a secondary pulley 43, and a belt 44, and a continuously variable transmission that continuously changes a gear ratio (ratio between variator input rotation and variator output rotation) by a change in belt contact diameter. Equipped with mechanical capabilities. The primary pulley 42 is composed of a fixed pulley 42a and a slide pulley 42b that are arranged coaxially with the primary rotation shaft 40 (=variator input shaft), and the slide pulley 42b slides by the primary pressure Ppri guided to the primary pressure chamber 45. To do. The secondary pulley 43 is composed of a fixed pulley 43a and a slide pulley 43b arranged coaxially with the secondary rotary shaft 41 (=variator output shaft), and the slide pulley 43b slides by the secondary pressure Psec guided to the secondary pressure chamber 46. To do. The belt 44 is stretched around the V-shaped sheave surface of the primary pulley 42 and the V-shaped sheave surface of the secondary pulley 43. This belt 44 is formed by two sets of laminated rings in which a plurality of annular rings are superposed from the inside to the outside and a punched plate material, and is attached by being laminated along the two sets of laminated rings in an annular shape by sandwiching them. And, The belt 44 may be a chain type belt in which a large number of chain elements arranged in the pulley traveling direction are connected by a pin penetrating in the pulley axial direction.

The final deceleration mechanism 5 is a mechanism that decelerates the secondary output rotation from the secondary rotation shaft 41 and imparts a differential function to the left and right drive wheels 6 and 6. The final reduction gear mechanism 5 is, as a reduction gear mechanism, an output gear 52 provided on the secondary rotary shaft 41, an idler gear 53 and a reduction gear 54 provided on the idler shaft 50, and a final gear provided on an outer peripheral position of the differential case. And a gear 55. The differential gear mechanism has a differential gear 56 interposed between the left and right drive shafts 51, 51.

As shown in FIG. 1, the control system of the engine vehicle includes a hydraulic control unit 7, a CVT control unit 8 (abbreviation “CVTCU”), and an engine control unit 9 (abbreviation “ECU”). The CVT control unit 8 and the engine control unit 9, which are electronic control systems, are connected by a CAN communication line 13 capable of exchanging information with each other.

The hydraulic control unit 7 controls the primary pressure Ppri guided to the primary pressure chamber 45, the secondary pressure Psec guided to the secondary pressure chamber 46, the forward clutch pressure Pfc to the forward clutch 31, the reverse brake pressure Prb to the reverse brake 32, and the like. It is a unit that regulates pressure. The hydraulic control unit 7 includes an oil pump 70 that is rotationally driven by the engine 1, and a hydraulic control circuit 71 that regulates various control pressures based on the discharge pressure from the oil pump 70. As the oil pump, the oil pump 70 and the electric oil pump may be used together. The hydraulic control circuit 71 includes a line pressure solenoid valve 72, a primary pressure solenoid valve 73, a secondary pressure solenoid valve 74, a select solenoid valve 75, and a lockup pressure solenoid valve 76. The solenoid valves 72, 73, 74, 75, 76 perform pressure adjustment operation according to a control command value (instruction current) output from the CVT control unit 8.

The line pressure solenoid valve 72 regulates the discharge pressure from the oil pump 70 to the instructed line pressure PL according to the line pressure command value output from the CVT control unit 8. The line pressure PL is an original pressure when adjusting various control pressures, and is a hydraulic pressure that suppresses belt slip and clutch slip with respect to the torque transmitted through the drive system.

The primary pressure solenoid valve 73 adjusts the primary pressure command value output from the CVT control unit 8 to the commanded primary pressure Ppri using the line pressure PL as the source pressure. The secondary pressure solenoid valve 74 reduces and adjusts the secondary pressure command value output from the CVT control unit 8 to the commanded secondary pressure Psec using the line pressure PL as the source pressure.

The select solenoid valve 75 adjusts the pressure to the forward clutch pressure Pfc or the backward brake pressure Prb commanded with the line pressure PL as the original pressure in accordance with the forward clutch pressure command value or the backward brake pressure command value output from the CVT control unit 8. To do.

The lockup pressure solenoid valve 76 regulates the LU command pressure Plu that engages/disengages/releases the lockup clutch 20 according to the command current Alu output from the CVT control unit 8.

The CVT control unit 8 performs line pressure control, shift control, forward/reverse switching control, lockup control, etc. In the line pressure control, a command value for obtaining a target line pressure according to the accelerator opening etc. is output to the line pressure solenoid valve 72. In the shift control, when the target gear ratio (target primary rotation NPRI*) is determined, a command value for obtaining the determined target gear ratio (target primary rotation NPRI*) is output to the primary pressure solenoid valve 73 and the secondary pressure solenoid valve 74. In the forward/reverse switching control, a command value for controlling engagement/disengagement of the forward clutch 31 and the reverse brake 32 is output to the select solenoid valve 75 according to the selected range position. In the lockup control, a command current Alu for controlling the LU command pressure Plu for engaging/slip-engaging/releasing the lockup clutch 20 is output to the lockup pressure solenoid valve 76.

The sensor information and switch information from the primary rotation sensor 90, the vehicle speed sensor 91, the secondary pressure sensor 92, the oil temperature sensor 93, the inhibitor switch 94, the brake switch 95, and the drum rotation sensor 96 are input to the CVT control unit 8. Further, sensor information from the secondary rotation sensor 97, the primary pressure sensor 98, the wheel speed sensor 99, etc. is input.

The sensor information from the engine rotation sensor 12, the accelerator opening sensor 14, etc. is input to the engine control unit 9. When the CVT control unit 8 requests the engine rotation information and the accelerator opening information to the engine control unit 9, the CVT control unit 8 receives the information on the engine speed NENG and the accelerator opening APO via the CAN communication line 13. Further, when the engine torque information is requested to the engine control unit 9, the estimated engine torque Te information is received via the CAN communication line 13. When the engine torque limit request is output from the CVT control unit 8 to the engine control unit 9, the engine control unit 9 limits the upper limit torque of the engine 1 according to the request by the intake air amount control or the ignition timing retard control.

FIG. 2 shows an example of a D range continuously variable shift schedule used when the variator 4 executes the continuously variable shift control in the automatic shift mode when the D range is selected.

"D-range shift mode" is an automatic shift mode in which the gear ratio is automatically and steplessly changed according to the vehicle operating condition. The shift control in the "D range shift mode" is performed at the operating point (on the D range continuously variable shift schedule of Fig. 2 specified by the vehicle speed VSP (vehicle speed sensor 91) and the accelerator opening APO (accelerator opening sensor 14). VSP, APO) determines the target primary speed NPRI*. Then, the actual primary rotation speed NPRI from the primary rotation sensor 90 is controlled by feedback control of the pulley hydraulic pressure to match the target primary rotation speed NPRI*. The speed ratio is represented by the slope of the speed ratio line drawn from the zero operating point, as is clear from the lowest speed ratio line and the highest speed ratio line of the D range continuously variable speed change schedule. Therefore, determining the target primary speed NPRI* according to the operating point (VSP, APO) determines the target gear ratio of the variator 4.

That is, the D-range continuously variable shift schedule used in the "D-range shift mode" is, as shown in FIG. It is set to continuously change the gear ratio within the range. For example, when the vehicle speed VSP is constant, when the accelerator is depressed, the target primary speed NPRI* increases and shifts in the downshift direction, and when the accelerator is released, the target primary speed NPRI* decreases and increases. Shift in the shift direction. When the accelerator opening APO is constant, the vehicle shifts in the upshift direction when the vehicle speed VSP increases, and shifts in the downshift direction when the vehicle speed VSP decreases.

[Configuration of control device]
FIG. 3 shows a control device of an embodiment in which control using the turbine speed information is executed in the CVT control unit 8. Hereinafter, the schematic configuration of the control device will be described with reference to FIG.

As shown in FIG. 3, the drive system to which the control device of the embodiment is applied includes an engine 1 (driving drive source), a torque converter 2, a forward/reverse switching mechanism 3, and a variator 4 (continuously variable transmission mechanism). The final reduction mechanism 5 and the drive wheels 6 are provided.

As shown in FIG. 3, the control system to which the control device of the embodiment is applied includes a CVT control unit 8 (transmission controller), an engine control unit 9, a primary pressure solenoid valve 73, a secondary pressure solenoid valve 74. , And a select solenoid valve 75. The CVT control unit 8 and the engine control unit 9 are connected by a CAN communication line 13. Information from the primary rotation sensor 90, the vehicle speed sensor 91, the drum rotation sensor 96, the secondary rotation sensor 97, etc. is input to the CVT control unit 8. Information from the engine rotation sensor 12, the accelerator opening sensor 14, etc. is input to the engine control unit 9.

The CVT control unit 8 has many basic controls/functions such as lockup control, select control, idle stop control/coast stop control, and self-diagnosis function as controls using turbine speed information. Refer to.

The forward/reverse switching mechanism 3 is interposed between the torque converter 2 and the variator 4, and has a double pinion type planetary gear 30 (planetary gear), a forward clutch 31, and a reverse brake 32. The double pinion type planetary gear 30 has a sun gear S, a carrier C, and a ring gear R as three rotating members whose rotational speed relationships are defined by linear characteristic lines in the collinear chart. The forward/reverse switching mechanism 3 includes a turbine rotation shaft 21, a drum rotation sensor 96, and a primary rotation sensor 90.

The turbine rotary shaft 21 connects the turbine runner 24 of the torque converter 2 and the sun gear S of the double pinion type planetary gear 30. Here, the rotation speed of the turbine rotation shaft 21 is the turbine rotation speed NTBN. The rotation speed of the engine output shaft 11 that connects the engine 1 and the pump impeller 23 of the torque converter 2 is the engine rotation speed NENG.

The drum rotation sensor 96 detects the rotation of the drum member 33 that connects the carrier C of the double pinion type planetary gear 30 and the ring gear R via the forward clutch 31. The drum rotation sensor 96 detects the rotation of the drum member 33 (=ring gear R) in place of the fact that the “turbine rotation sensor” that detects the rotation of the turbine rotation shaft 21 cannot be arranged in the layout. The rotation speed of the drum member 33 (=ring gear R) is the drum rotation speed NDRUM. The reverse brake 32 is disposed between the ring gear R of the double pinion type planetary gear 30 and the transmission case.

The primary rotation sensor 90 detects the rotation of the primary rotation shaft 40 that connects the carrier C of the double pinion type planetary gear 30 and the primary pulley 42. Here, the rotation speed of the primary rotation shaft 40 is the primary rotation speed NPRI. The rotation speed of the secondary rotation shaft 41 connected to the secondary pulley 43 is the secondary rotation speed NSEC.

The CVT control unit 8 has a turbine rotation estimation unit 80 (turbine rotation estimation means) that calculates a turbine rotation estimated value NTBN′ of the turbine rotation shaft 21 based on the detection values of the drum rotation sensor 96 and the primary rotation sensor 90. In other words, since the “turbine rotation sensor” is not provided, the turbine rotation speed information is calculated based on the detected values of the drum rotation sensor 96 and the primary rotation sensor 90 instead of the detected value of the turbine rotation sensor. Estimated value NTBN' is used.

When the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown, the turbine rotation estimation unit 80 determines the turbine rotation estimation value NTBN′ by the unknown one rotation estimation value and the other sensor detection value. calculate. At this time, the rotation estimated value is estimated using at least two of the running/stopped state, the engaged/released state of the forward clutch 31 and the reverse brake 32, and the gear ratio of the variator 4.

When calculating the estimated turbine rotation value NTBN', the traveling scene is divided into a forward clutch 31 engagement scene, a reverse brake 32 engagement scene, and a forward clutch 31 and reverse brake 32 release scene while traveling. Then, even when the vehicle is stopped, it is divided into the engagement scene of the forward clutch 31, the engagement scene of the reverse brake 32, and the release scene of the forward clutch 31 and the reverse brake 32.

That is, the turbine rotation estimated value NTBN′ is divided into each of six scenes, and in each scene, the detection value of the drum rotation sensor 96 is unknown and the detection value of the primary rotation sensor 90 is unknown. Calculated separately for and. Incidentally, the transitional scene of the engagement→release of the forward clutch 31 and the reverse brake 32 or the transitional scene of the release→engagement is dealt with by switching the turbine speed information in three scenes according to the range position. Further, when the forward clutch 31 and the reverse brake 32 are released and the rotation constraint condition is not determined on the collinear chart, the turbine rotation estimated value NTBN' is calculated without calculating the turbine rotation estimated value NTBN'. The turbine rotation estimated value NTBN' is considered and estimated like the rotation speed NENG.

[Turbine rotation estimated value calculation processing configuration]
FIG. 4 shows a flow of turbine rotation estimated value calculation processing executed by the turbine rotation estimation unit 80 of the CVT control unit 8 of the embodiment. Hereinafter, each step of FIG. 4 will be described.

In S1, following the start or NO judgment in S1 or NO judgment in S2, it is judged whether or not the precondition is satisfied. If YES (precondition is satisfied), the process proceeds to S2, and if NO (precondition is not satisfied), the determination of S1 is repeated.

Here, the "preconditions" are the detection conditions of the engine speed NENG and the input conditions of the soft switch. The preconditions for the normal judgment of the self-diagnosis function OBD (On-Board Diagnostics) are the same.

In S2, following the YES judgment in S1, it is judged whether the scene is other than the sensor abnormality judgment prohibited scene. If YES (other than the sensor abnormality determination prohibited scene), the process proceeds to S3. If NO (sensor abnormality determination prohibited scene), the process returns to S1.

Here, the "sensor abnormality determination prohibited scene" means a scene in which the drum rotation sensor 96 does not detect the drum rotation speed NDRUM even in a normal state, or the drum rotation speed NDRUM is low rotation and the primary rotation speed NPRI is low rotation. Say the scene.

The specific scenes of the "sensor abnormality determination prohibited scene" are the following scenes (1) to (7) and correspond to (1) to (7) shown in FIG. The forward clutch 31 is called "FWD/C" and the reverse brake 32 is called "REV/B".
(1) Stopped by FWD/C engagement or REV/B engagement, idling stop (however, because primary rotation is not detected, it is outside the detection area).
(2) Moving forward with the conclusion of REV/B.
(3) The vehicle is moving backward with REV/B concluded, and the vehicle is not traveling REV/B.
(4) Being backwards without REV/B.
(5) Being in reverse with no REV/B concluded.
(6) Moving forward without REV/B (when the engine stall under the worst conditions and the turbine speed is 0 rpm, the planet is outside the detection range).
(7) Turbine speed reverses when REV/B is not engaged (engine 1 does not reverse).

In S3, following the YES judgment in S2, it is judged whether the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown. If YES (one detection value is unknown), the process proceeds to S5, and if NO (both detection values are clear), the process proceeds to S4.

Here, whether the sensor detection value is unknown or not is determined by determining the disconnection abnormality of each of the drum rotation sensor 96 and the primary rotation sensor 90, and continuously outputting the rotation speed of zero despite the rotation abnormality. If it is determined that the sensor detection value is unknown.

In S4, following the NO determination in S3, the turbine rotation speed estimated value NTBN' is calculated from the drum rotation speed NDRUM from the drum rotation sensor 96, the primary rotation speed NPRI from the primary rotation sensor 90, and the rotation speed relationship in the alignment chart. Calculate and proceed to return.

Here, in the case of the double pinion type planetary gear 30, if the rotation speeds of two rotation members of the sun gear S, the carrier C and the ring gear R are known, the rotation speed of the remaining one rotation member is determined. Therefore, if the drum rotation speed NDRUM (=ring gear R rotation speed) and the primary rotation speed NPRI (=carrier C rotation speed) are clear from the sensor values, the turbine rotation estimated value NTBN' (=sun gear S rotation speed) is obtained. ) Is calculated by both rotational speeds NDRUM, NPRI and the tooth ratio α.

In S5, following the YES judgment in S3, it is judged whether or not the vehicle is running. If YES (running), proceed to S6, and if NO (while stopped), proceed to S11.

Here, whether the vehicle is running or stopped is determined by the sensor detection value from the secondary rotation sensor 97. Specifically, when the secondary rotation speed NSEC is converted into the vehicle speed VSP, it is determined that the vehicle speed VSP is running when it is equal to or higher than the vehicle stop determination threshold value VSP1, and it is determined that the vehicle speed VSP is less than the vehicle stop determination threshold value VSP1. It

In S6, following the YES judgment in S5, it is judged whether or not the forward clutch 31 is in the engaged state. If YES (during FWD/C running), proceed to S8. If NO (during FWD/C release), proceed to S7. Here, the engaged state of the forward clutch 31 is determined by, for example, the select range position being the forward traveling range such as the D range, the L range, or the S range.

In S7, following the NO determination in S6, it is determined whether or not the reverse brake 32 is in the engaged state. If YES (during REV/B running), proceed to S9. If NO (during FWD/C and REV/B release traveling), proceed to S10. Here, the engagement state of the reverse brake 32 is determined by, for example, the select range position being the R range which is the reverse traveling range.

In S8, following the YES determination in S6, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the forward clutch 31 is in the engaged state, so the drum rotation speed NDRUM is replaced with the primary rotation speed NPRI, Calculate the estimated rotation value NTBN' and proceed to return. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the forward rotation clutch 31 is in the engaged state, so the primary rotation speed NPRI is replaced with the drum rotation speed NDRUM, the turbine rotation speed estimated value NTBN' is calculated, and the process returns. move on.

In S9, following the YES determination in S7, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the reverse brake 32 is in the engaged state, so the drum rotation speed NDRUM is replaced with NDRUM=0, and the turbine rotation speed is changed. Calculate the estimated value NTBN' and proceed to return. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90 and the reverse brake 32 is in the engaged state, the gear ratio of the variator 4 is the lowest gear ratio. Estimate and calculate from the lowest gear ratio and the secondary speed NSEC. Then, the turbine rotation estimated value NTBN' is calculated from the primary rotation estimated value NPRI' and the reverse gear ratio (R gear ratio), and the process returns.

In S10, following the NO determination in S7, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the turbine rotation estimated value NTBN' is regarded as the engine rotation speed NENG. Then, the drum rotation speed NDRUM is calculated from the turbine rotation estimated value NTBN' (=NENG) and the primary rotation speed NPRI on the collinear chart, and the process proceeds to the return. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the turbine rotation estimated value NTBN' is regarded as the engine rotation speed NENG. Then, the primary rotational speed NPRI is calculated from the turbine rotational speed estimated value NTBN' (=NENG) and the drum rotational speed NDRUM on the collinear chart, and the process returns. The primary speed NPRI calculated from the collinear diagram is the primary speed upper limit value calculated from the secondary speed NSEC and the lowest gear ratio of the variator 4, and the primary speed NPRI calculated from the secondary speed NSEC and the highest gear ratio of the variator 4. Limited by the lower limit of rotation speed.

In S11, following the NO determination in S5, it is determined whether or not the forward clutch 31 is in the engaged state. If YES (while the FWD/C is stopped and stopped), proceed to S13, and if NO (when the FWD/C is released and stopped), proceed to S12. Here, the engaged state of the forward clutch 31 is determined by, for example, the select range position being the forward traveling range such as the D range, the L range, or the S range.

In S12, following the NO determination in S11, it is determined whether or not the reverse brake 32 is in the engaged state. If YES (when REV/B is stopped), proceed to S14, and if NO (when FWD/C and REV/B are released), proceed to S15. Here, the engagement state of the reverse brake 32 is determined by, for example, the select range position being the R range which is the reverse traveling range.

In S13, following the YES determination in S11, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the drum rotation speed NDRUM is replaced with the primary rotation speed NPRI, the turbine rotation estimated value NTBN' is calculated, and the return is made. Go to. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the primary rotation speed NPRI is replaced with NPRI=0 (because the vehicle is stopped), the turbine rotation estimated value NTBN′ is calculated, and the process returns.

In S14, following the YES determination in S14, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the drum rotation speed NDRUM is replaced with NDRUM=0, the turbine rotation estimated value NTBN' is calculated, and the process returns. move on. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the primary rotation speed NPRI is replaced with NPRI=0, the turbine rotation estimated value NTBN' is calculated, and the routine proceeds to return.

In S15, following the NO determination in S14, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the turbine rotation estimated value NTBN' is regarded as the engine rotation speed NENG. Then, the drum rotation speed NDRUM is calculated from the turbine rotation estimated value NTBN' (=NENG) and the primary rotation speed NPRI on the collinear chart, and the process proceeds to the return. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the turbine rotation estimated value NTBN' is regarded as the engine rotation speed NENG. Then, the primary rotational speed NPRI is set to NPRI=0 (because the vehicle is stopped), and the process proceeds to return.

Next, I will explain "background technology and issues" and "solutions to issues". Then, the operation of the embodiment is "a turbine rotation estimated value calculation operation in a normal scene", "a turbine rotation estimated value calculation operation in a traveling scene in which the sensor detection value is unknown", and "a turbine rotation estimated value calculation operation in a traveling scene in which the sensor detection value is unknown". Turbine rotation estimated value calculation operation" will be described separately.

[Background Technology and Issues]
As shown in FIG. 6, the forward/reverse switching mechanism of the comparative example is disposed between a torque converter and a variator (not shown), and includes a double pinion type planetary gear, a forward clutch, and a reverse brake. The double pinion type planetary gear has a sun gear S, a carrier C, and a ring gear R.

▽The forward clutch is provided at an intermediate position of the member connecting the sun gear S of the double pinion type planetary gear and the carrier C. The reverse brake is arranged between the ring gear R and the transmission case. The turbine rotation sensor (Nt sensor) detects the rotation speed of the turbine rotation shaft that connects the turbine runner of the torque converter and the sun gear S. The primary rotation sensor (Npri sensor) detects the rotation of the primary rotation shaft that connects the carrier C and the primary pulley of the variator.

That is, in the case of the forward/reverse switching mechanism of the comparative example shown in FIG. 6, the position of the forward clutch is at the middle position of the member connecting the sun gear S and the carrier C. On the other hand, in the case of the forward/reverse switching mechanism 3 of the embodiment shown in FIG. 3, the position of the forward clutch is set to the middle position of the drum member 33 that connects the ring gear R and the carrier C, and the torque converter is aimed at a compact layout. And the setting interval between the forward/reverse switching mechanism is narrowed.

As described above, in the embodiment, the setting position of the forward clutch is changed, so that the turbine rotation sensor provided in the forward/reverse switching mechanism of the comparative example cannot be provided in a layout. Therefore, a drum rotation sensor is provided instead of the turbine rotation sensor, and the turbine rotation speed information is estimated from the drum rotation speed and the primary rotation speed by using the rotation speed relationship based on the alignment chart of the double pinion type planetary gear. ..

Therefore, when estimating the turbine rotation speed from the drum rotation speed and the primary rotation speed, if only one of the drum rotation speed and the primary rotation speed is unknown, it is not possible to draw the linear characteristic that defines the rotation relationship on the alignment chart. Therefore, when only one of the drum rotation speed and the primary rotation speed is unknown, there arises a problem that the turbine rotation estimated value cannot be calculated using the rotation speed relationship based on the alignment chart.

[Measures to solve problems]
With respect to the above problem, the present inventor clarifies a scene in which the turbine rotation speed cannot be correctly read due to a change in the sensor position from the viewpoint of hardware, and refers to the turbine rotation speed and a derived signal from the viewpoint of software. The control was extracted and its effect was confirmed. The turbine rotation speed information can be acquired even if only one of the drum rotation speed and the primary rotation speed is unknown.

That is, when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown, at least two of the running/stopped state, the engaged/released state of the forward clutch 31 and the reverse brake 32, and the gear ratio of the variator 4 are determined. One of them is used to estimate the rotation speed of an unknown detected value, and calculate the turbine rotation estimated value NTBN′ from the estimated rotation estimated value and the other sensor detected value.

Therefore, when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown, at least two of the running/stopped state, the engaged state of the forward clutch 31 or the reverse brake 32, and the gear ratio of the variator 4 are determined. Can be used to estimate the drum speed or primary speed. That is, the rotation speed of the carrier C of the forward/reverse switching mechanism 3 becomes positive in the traveling state, and the rotation speed of the carrier C of the forward/reverse switching mechanism 3 becomes zero in the stopped state. When the forward clutch 31 is engaged, the three elements S, C, R of the forward/reverse switching mechanism 3 have the same rotational speed. In the engaged state of the reverse brake 32, the rotation speed of the ring gear R of the forward/reverse switching mechanism 3 is zero, the sun gear S is positive, and the carrier C is negative. At this time, if the rotation speed of the carrier C is estimated by the gear ratio of the variator 4, the rotation speed of the sun gear S (=turbine rotation speed) is determined.

Therefore, when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown, it is possible to ensure acquisition of turbine rotation information by estimation. As a result, when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown, it is possible to continue the control using the turbine rotation speed information referred to by many basic controls/functions. Specifically, for example, during execution of basic control/functions such as lock-up control, select control, idle stop control/coast stop control, self-diagnosis function, etc., the detection value of the drum rotation sensor 96 or the detection of the primary rotation sensor 90 is detected. Even if the value becomes unknown, the basic control/function can continue to be executed.

[Calculation of turbine rotation estimated value in normal scene]
FIG. 7 shows the calculation processing of the turbine rotation estimated value NTBN′ when both the detection value of the drum rotation sensor 96 and the detection value of the primary rotation sensor 90 can be used. Hereinafter, the turbine rotation estimation value calculation operation in a normal scene where two sensor detection values can be used will be described with reference to FIGS. 4 and 7.

When the precondition is satisfied, the scene is not a sensor abnormality determination prohibited scene, and both the detection value of the drum rotation sensor 96 and the detection value of the primary rotation sensor 90 can be used, S1→S2→S3→S4 in the flowchart of FIG. → Proceed to return.

In S4, the turbine rotation estimated value NTBN' is calculated from the drum rotation speed NDRUM from the drum rotation sensor 96, the primary rotation speed NPRI from the primary rotation sensor 90, and the rotation speed relationship in the alignment chart. Turbine rotation estimated value NTBN' calculation formula (1) is
NTBN'={NDRUM-NPRI(1-α)}/α (1)
Is. However, the tooth number ratio α is obtained by the formula of (the number of teeth of the sun gear S)÷(the number of teeth of the ring gear R).

Therefore, when the forward clutch 31 is in the engaged state, the turbine rotation estimated value NTBN' becomes according to the magnitude of the drum rotation speed NDRUM or the primary rotation speed NPRI, as shown in the collinear characteristic D in FIG. 7. , And matches the drum speed NDRUM or the primary speed NPRI.

When the reverse brake 32 is in the engaged state, as shown in the collinear chart characteristic E of FIG. 7, it corresponds to the magnitude of the primary rotation speed NPRI, and the turbine rotation estimated value NTBN′ is calculated by the equation (1) above. Drum speed NDRUM was set to zero,
NTBN'=NPRI(1-α)/α...(1')
It is calculated by the formula.

When both the forward clutch 31 and the reverse brake 32 are in the disengaged state, as shown by the collinear chart characteristic F in FIG. 7, it becomes according to the magnitudes of the drum rotation speed NDRUM and the primary rotation speed NPRI, and the turbine rotation estimation is performed. The value NTBN' is calculated by the above equation (1).

[Estimated turbine rotation value calculation function in driving scenes where the sensor detection value is unknown]
The description of the turbine rotation estimated value calculation operation will be divided into (during forward clutch engagement traveling), (during backward brake engagement traveling), and (during forward clutch and backward brake release traveling).

(While traveling with the forward clutch engaged)
FIG. 8 shows the calculation processing of the turbine rotation estimated value NTBN′ when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown during the engagement travel of the forward clutch (FWD/C). Hereinafter, the turbine rotation estimated value calculation operation in the forward clutch engagement traveling scene in which the sensor detection value is unknown will be described based on FIGS. 4 and 8.

The precondition is satisfied, the scene is other than the sensor abnormality determination prohibited scene, and the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the forward clutch 31 is engaged and traveling. In this case, in the flowchart of FIG. 4, the process proceeds to S1→S2→S3→S5→S6→S8→Return.

In S8, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the drum rotation speed NDRUM is replaced with the primary rotation speed NPRI, and the turbine rotation estimated value NTBN' is calculated. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the primary rotation speed NPRI is replaced with the drum rotation speed NDRUM, and the turbine rotation estimated value NTBN' is calculated.

When the drum rotation sensor 96 is disconnected and the drum rotation speed NDRUM is unknown, the collinear diagram recognized by the CVT control unit 8 shows a broken line characteristic passing through NDRUM=0 as shown by ○ in FIG. 8(a). Become. Therefore, the turbine rotation estimated value NTBN' becomes the same number of revolutions as when the vehicle is running backward with the reverse brake 32 engaged. Therefore, the estimated turbine rotation speed NTBN' is about 5% lower than the actual turbine rotation speed NTBN according to the alignment chart shown in the solid line characteristic of FIG. 8(a), and the input torque is estimated to be high. If the input torque is overestimated, the hydraulic pressure is increased by the amount of the input torque, which leads to deterioration of fuel consumption.

On the other hand, when the primary rotation sensor 90 is disconnected and the primary rotation speed NPRI is unknown, the collinear diagram recognized by the CVT control unit 8 is a broken line passing through NPRI=0 as shown by ○ in FIG. 8(b). Become a characteristic. Therefore, the estimated turbine rotation speed NTBN' becomes about twice as high as the actual turbine rotation speed NTBN according to the alignment chart shown in the solid line characteristic of FIG. 8B, and the input torque is estimated to be low. If the input torque is estimated to be low, the oil pressure is reduced by the amount of the input torque being low, which causes the forward clutch 31 and the belt 44 to slip.

On the other hand, when the drum rotation speed NDRUM is unknown, the drum rotation speed NDRUM is replaced with the primary rotation speed NPRI to calculate the turbine rotation speed estimated value NTBN' as shown by the solid line characteristic in Fig. 8(c). When the primary rotation speed NPRI is unknown, the turbine rotation speed estimated value NTBN' is calculated by replacing the primary rotation speed NPRI with the drum rotation speed NDRUM as shown by the solid line characteristic in FIG. 8(c).

For this reason, the calculated turbine rotation speed estimated value NTBN' matches the actual turbine rotation speed NTBN. In other words, the input torque is not overestimated when the drum rotation speed NDRUM is unknown as in the case of relying on the recognition of the CVT control unit 8, and the deterioration of fuel efficiency due to the increase in hydraulic pressure can be prevented. Further, as in the case of relying on the recognition of the CVT control unit 8, the input torque is not underestimated when the primary rotation speed NPRI is unknown, and the occurrence of slippage of the forward clutch 31 and the belt 44 due to the reduction of the hydraulic pressure. It can be prevented.

(While running reverse brake)
FIG. 9 shows the calculation processing of the turbine rotation estimated value NTBN′ when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown during the engagement travel of the reverse brake (REV/B). Hereinafter, a turbine rotation estimated value calculation operation in a reverse brake engagement traveling scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 9.

The precondition is satisfied, it is outside the sensor abnormality determination prohibited scene, and the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the reverse brake 32 is engaged. In this case, in the flowchart of FIG. 4, the process proceeds to S1→S2→S3→S5→S6→S7→S9→Return.

In S9, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the drum rotation speed NDRUM is replaced with NDRUM=0, and the turbine rotation estimated value NTBN' is calculated. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the primary rotation speed NPRI is estimated and calculated by the lowest gear ratio of the variator 4 and the secondary rotation speed NSEC. Then, the turbine rotation estimated value NTBN' is calculated from the primary rotation estimated value NPRI' and the reverse gear ratio (R gear ratio).

When the drum rotation sensor 96 is disconnected and the drum rotation speed NDRUM is unknown, the collinear diagram recognized by the CVT control unit 8 shows a broken line characteristic passing through NDRUM=0 as shown by ○ in FIG. 9(a). Become. Therefore, the turbine rotation estimated value NTBN' becomes the same number of revolutions as when the vehicle is running backward with the reverse brake 32 engaged. Therefore, the estimated turbine rotation speed NTBN' is no different from the actual turbine rotation speed NTBN according to the alignment chart shown in the solid line characteristic of FIG. 9(a).

On the other hand, when the primary rotation sensor 90 is disconnected and the primary rotation speed NPRI is unknown, the collinear diagram recognized by the CVT control unit 8 is a broken line passing through NPRI=0 as shown by ◯ in FIG. 9(b). Become a characteristic. Therefore, the turbine rotation estimated value NTBN' becomes zero rotation. In other words, it is lower than the actual turbine speed NTBN according to the collinear chart shown in the solid line characteristic of FIG. If the input torque is estimated to be high, the higher the input torque is, the higher the hydraulic pressure is, which leads to deterioration of fuel efficiency.

On the other hand, when the drum speed NDRUM is unknown, the drum speed NDRUM is replaced with NDRUM=0 to calculate the estimated turbine speed NTBN' as shown by the solid line characteristics in Fig. 9(c). When the primary speed NPRI is unknown, the primary speed NPRI is estimated and calculated by the lowest speed ratio of the variator 4 and the secondary speed NSEC. Then, the turbine rotation estimated value NTBN' is calculated from the primary rotation estimated value NPRI' and the reverse gear ratio (R gear ratio).

For this reason, the calculated turbine rotation speed NTBN' will match the actual turbine rotation speed NTBN when the drum rotation speed NDRUM is unknown. Then, the calculated turbine rotation speed estimated value NTBN' is enhanced in agreement with the actual turbine rotation speed NTBN when the primary rotation speed NPRI is unknown. In other words, when the primary rotation speed NPRI is unknown, the input torque is not overestimated as in the case where the CVT control unit 8 is left to be recognized, and the deterioration of fuel efficiency due to the increase in hydraulic pressure can be prevented.

(While the forward clutch and reverse brake are released)
FIG. 10 is a turbine rotation estimated value NTBN when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown during the disengagement travel of the forward clutch (FWD/C) and the reverse brake (REV/B). 'Shows the calculation process. Hereinafter, the turbine rotation estimated value calculation operation in the open traveling scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 10.

The precondition is satisfied, it is outside the sensor abnormality determination prohibited scene, and the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the forward clutch 31 and the reverse brake 32 are disengaged. In this case, in the flowchart of FIG. 4, the process proceeds to S1→S2→S3→S5→S6→S7→S10→Return.

In S10, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the estimated turbine rotation speed NTBN' is regarded as the engine rotation speed NENG. Then, the drum rotation speed NDRUM is calculated from the turbine rotation estimated value NTBN' (=NENG) and the primary rotation speed NPRI on the collinear chart. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the turbine rotation estimated value NTBN' is regarded as the engine rotation speed NENG. Then, the primary rotation speed NPRI is calculated from the turbine rotation estimated value NTBN' (=NENG) and the drum rotation speed NDRUM on the collinear chart. The primary rotation speed NPRI calculated from the collinear chart is calculated from the primary rotation speed upper limit value calculated from the secondary rotation speed NSEC and the lowest gear ratio of the variator 4, and the secondary rotation speed NSEC and the highest gear ratio of the variator 4. It is limited by the lower limit of primary speed.

When the drum rotation sensor 96 is disconnected and the drum rotation speed NDRUM is unknown, the collinear diagram recognized by the CVT control unit 8 shows a broken line characteristic passing through NDRUM=0 as shown by a circle in FIG. Become. Therefore, the turbine rotation estimated value NTBN' becomes the same number of revolutions as when the vehicle is running backward with the reverse brake 32 engaged. Therefore, the estimated turbine rotation speed NTBN' is about 5% lower than the actual turbine rotation speed NTBN according to the alignment chart shown in the solid line characteristic of FIG. 10(a), and the input torque is estimated to be high. If the input torque is overestimated, the hydraulic pressure is increased by the amount of the input torque, which leads to deterioration of fuel consumption.

On the other hand, when the primary rotation sensor 90 is disconnected and the primary rotation speed NPRI is unknown, the collinear diagram recognized by the CVT control unit 8 is a broken line passing through NPRI=0 as shown by ◯ in FIG. 10(b). Become a characteristic. Therefore, the estimated turbine rotation speed NTBN' becomes about twice as high as the actual turbine rotation speed NTBN according to the alignment chart shown in the solid line characteristic of FIG. 10(b), and the input torque is estimated to be low. If the input torque is estimated to be low, the oil pressure is reduced by the amount of the input torque being low, which causes the forward clutch 31 and the belt 44 to slip.

On the other hand, when the drum speed NDRUM is unknown, the estimated turbine speed NTBN' is regarded as the engine speed NENG, as shown by the solid line characteristics in Fig. 10(c). When the primary rotation speed NPRI is unknown, the turbine rotation speed estimated value NTBN' is regarded as the engine rotation speed NENG, as in the case where the drum rotation speed NDRUM is unknown, as shown by the solid line characteristic in FIG. 10(c).

Therefore, by considering the estimated turbine speed NTBN' as the engine speed NENG, it is possible to give a value close to the actual turbine speed NTBN. While the vehicle is traveling in the N range by releasing the forward clutch 31 and the reverse brake 32, there is no control for referring to the turbine rotation information, so control using turbine rotation information due to an abnormality in the drum rotation sensor 96 or the primary rotation sensor 90 is performed. Does not affect

[Evaluation of turbine rotation estimated value in stationary scene where sensor detection value is unknown]
The description of the turbine rotation estimated value calculation operation is divided into (while the forward clutch is engaged and stopped), (while the reverse brake is engaged and stopped), and (when the forward clutch and reverse brake are released and stopped).

(While the forward clutch is engaged and stopped)
FIG. 11 shows the calculation processing of the turbine rotation estimated value NTBN′ when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the forward clutch (FWD/C) is engaged and stopped. Hereinafter, the turbine rotation estimated value calculation operation in the forward clutch engagement/stop scene where the sensor detection value is unknown will be described with reference to FIGS. 4 and 11.

The precondition is satisfied, it is outside the sensor abnormality determination prohibited scene, and the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the forward clutch 31 is engaged and stopped. In this case, in the flowchart of FIG. 4, the process proceeds to S1→S2→S3→S5→S11→S13→Return.

In S13, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the drum rotation speed NDRUM is replaced with the primary rotation speed NPRI, and the turbine rotation estimated value NTBN' is calculated. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the primary rotation speed NPRI is replaced with NPRI=0 (because the vehicle is stopped), and the turbine rotation estimated value NTBN′ is calculated.

As described above, when the drum rotation speed NDRUM is unknown, the forward clutch 31 is engaged and the vehicle is stopped. Therefore, as shown by the solid line characteristics in FIG. 11, the drum rotation speed NDRUM=primary rotation speed NPRI (=0). As usual, the turbine rotation estimated value NTBN' (=0) may be estimated. When the primary rotation speed NPRI is unknown, the forward clutch 31 is engaged and the vehicle is stopped. Therefore, as shown by the solid line characteristics in FIG. 11, the estimated turbine rotation speed NTBN is set as the primary rotation speed NPRI (=0) as usual. '(=0) should be estimated. Note that, while the vehicle is stopped with the forward clutch 31 engaged, unlike during traveling, there is no influence of the vehicle behavior in the control using the turbine rotation information.

(While the reverse brake is engaged and stopped)
FIG. 12 shows calculation processing of the turbine rotation estimated value NTBN′ when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the reverse brake (REV/B) is engaged and stopped. Hereinafter, the operation of the turbine rotation estimated value calculation operation in the reverse brake engagement/stop scene in which the sensor detection value is unknown will be described with reference to FIGS.

The precondition is satisfied, it is outside the sensor abnormality determination prohibited scene, and the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the reverse brake 32 is engaged and stopped. In this case, in the flowchart of FIG. 4, the process proceeds to S1→S2→S3→S5→S11→S12→S14→Return.

In S14, if the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the drum rotation speed NDRUM is replaced with NDRUM=0, and the turbine rotation estimated value NTBN' is calculated. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the primary rotation speed NPRI is replaced with NPRI=0, and the turbine rotation estimated value NTBN′ is calculated.

As described above, when the drum speed NDRUM is unknown, the reverse brake 32 is engaged and the vehicle is stopped. Therefore, as shown by the solid line characteristics in FIG. 12, the turbine speed is estimated as usual with the drum speed NDRUM=0. The value NTBN' (=0) may be estimated. When the primary rotation speed NPRI is unknown, the reverse brake 32 is engaged and the vehicle is stopped. Therefore, as shown by the solid line characteristics in FIG. 12, the estimated turbine rotation speed NTBN' (normally with the primary rotation speed NPRI=0 ( =0) may be estimated. Note that, while the vehicle is stopped with the reverse brake 32 engaged, unlike the case of traveling, there is no influence of the vehicle behavior in the control using the turbine rotation information.

(While the forward clutch and reverse brake are released and stopped)
FIG. 13 is a turbine rotation estimated value NTBN when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the forward clutch (FWD/C) and the reverse brake (REV/B) are released and stopped. 'Shows the calculation process. Hereinafter, the operation of calculating the estimated turbine rotation value in the released vehicle stop scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 13.

The precondition is satisfied, it is outside the sensor abnormality determination prohibited scene, and the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown while the forward clutch 31 and the reverse brake 32 are released and stopped. In this case, in the flowchart of FIG. 4, the process proceeds to S1→S2→S3→S5→S11→S12→S15→return.

In S15, when the drum rotation speed NDRUM is unknown due to an abnormality in the drum rotation sensor 96, the turbine rotation speed estimated value NTBN' is regarded as the engine rotation speed NENG. Then, the drum rotation speed NDRUM is calculated from the turbine rotation estimated value NTBN' (=NENG) and the primary rotation speed NPRI on the collinear chart. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation sensor 90, the turbine rotation estimated value NTBN' is regarded as the engine rotation speed NENG. Then, the primary rotation speed NPRI is set to NPRI=0 (because the vehicle is stopped).

As described above, when the drum rotation speed NDRUM is unknown, the rotation speed of each rotating member S, C, R is determined by the balance of forces when the accelerator is operated. It can be estimated basically by considering The drum rotation speed NDRUM can be basically estimated by the turbine rotation estimated value NTBN' (=NENG), the primary rotation speed NPRI, and the alignment chart.

When the primary rotation speed NPRI is unknown, the rotation speed of each rotating member S, C, R is determined by the balance of force when the accelerator is operated, but the estimated turbine rotation speed NTBN' is regarded as the engine rotation speed NENG. Basically, it can be estimated. The primary rotation speed NPRI can be estimated because the vehicle is stopped and NPRI=0.

As described above, in the control device for the belt type continuously variable transmission CVT of the embodiment, the effects listed below can be obtained.

(1) A torque converter 2 connected to a driving source (engine 1) for traveling, a forward/reverse switching mechanism 3 connected to the torque converter 2, and a continuously variable transmission mechanism (variator 4) connected to the forward/reverse switching mechanism 3. ) And a transmission controller (CVT control unit 8),
The forward/reverse switching mechanism 3 has a planetary gear (double pinion type planetary gear 30), a forward clutch 31, and a reverse brake 32. The continuously variable transmission mechanism (variator 4) is mounted on a primary pulley 42 and a secondary pulley 43. The transmission controller (CVT control unit 8) has a belt 44 to be passed, and the transmission controller (CVT control unit 8) executes a control using the turbine speed information input to the forward/reverse switching mechanism 3 (a belt type continuously variable transmission CVT. ) Control device,
A turbine rotary shaft 21 that connects a turbine runner 24 of the torque converter 2 and a sun gear S of a planetary gear (double pinion type planetary gear 30);
A carrier C and a ring gear R of a planetary gear (double pinion type planetary gear 30) connected through a forward clutch 31;
A drum rotation sensor 96 for detecting the number of rotations of the drum member 33 connected to the ring gear R;
A primary rotation sensor 90 that detects the number of rotations of a primary rotation shaft 40 that connects the carrier C of the planetary gear (double pinion type planetary gear 30) and the primary pulley 42,
Turbine rotation estimation means (turbine rotation estimation unit 80) for calculating a turbine rotation estimation value NTBN′ of the turbine rotation shaft 21 based on detection values of the drum rotation sensor 96 and the primary rotation sensor 90,
When the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown, the turbine rotation estimation means (turbine rotation estimation unit 80) is in the running/stopped state, the engaged/released state of the forward clutch 31 and the reverse brake 32. , At least two of the gear ratios of the continuously variable transmission mechanism (variator 4) are used to estimate the rotation speed of an unknown detection value, and the turbine is determined by the estimated rotation speed and the other sensor detection value. Calculate the rotation estimate NTBN'.
Therefore, when the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown, it is possible to ensure acquisition of turbine rotation information by estimation.

(2) The turbine rotation estimation means (turbine rotation estimation unit 80) replaces the drum rotation speed NDRUM with the primary rotation speed NPRI when the forward clutch 31 is engaged during traveling and the drum rotation speed NDRUM is unknown. Drum rotation estimated value NDRUM', turbine rotation estimated value NTBN',
Calculated by the drum rotation estimated value NDRUM' and the detection value from the primary rotation sensor 90,
During traveling, when the forward clutch 31 is in the engaged state, and the primary rotation speed NPRI is unknown, the primary rotation speed NPRI is replaced with the drum rotation speed NDRUM to obtain the primary rotation estimated value NPRI′, and the turbine rotation estimated value NTBN′ is It is calculated by the primary rotation estimated value NPRI′ and the detection value from the drum rotation sensor 96.
Therefore, when the forward clutch 31 is engaged and the drum rotation speed NDRUM or the primary rotation speed NPRI is unknown during traveling, the unknown drum rotation estimated value NDRUM' or primary rotation estimated value NPRI' and the turbine rotation estimated value NTBN are unknown. 'Can be calculated.
That is, since the forward gear ratio of the planetary gear (double pinion type planetary gear 30) becomes 1 when the forward clutch 31 is in the engaged state, the drum rotation speed NDRUM=the primary rotation speed NPRI should be obtained. Therefore, it is possible to estimate the drum rotation estimated value NDRUM' or the primary rotation estimated value NPRI', and it is possible to estimate the turbine rotation estimated value NTBN' based on the alignment chart as usual.

(3) The turbine rotation estimation means (turbine rotation estimation unit 80) replaces the drum rotation speed NDRUM with zero and estimates the drum rotation when the reverse brake 32 is engaged and the drum rotation speed NDRUM is unknown during traveling. As the value NDRUM', the turbine rotation estimated value NTBN' is calculated by the drum rotation estimated value NDRUM' and the detection value from the primary rotation sensor 90,
When the reverse brake 32 is engaged during traveling and the primary speed NPRI is unknown, the primary speed NPRI is calculated by the lowest speed ratio of the continuously variable transmission (variator 4) and the secondary speed PSEC. The rotation speed estimated value NPRI′ is set, and the turbine rotation estimated value NTBN′ is calculated based on the primary rotation estimated value NPRI′ and the detection value from the drum rotation sensor 96.
Therefore, when the reverse brake 32 is engaged and the drum rotation speed NDRUM or the primary rotation speed NPRI is unknown during traveling, the unknown drum rotation estimated value NDRUM' or primary rotation estimated value NPRI' and the turbine rotation estimated value NTBN are unknown. 'Can be calculated.
That is, when the drum rotation speed NDRUM is unknown, it is supposed that the drum rotation speed NDRUM=0 by the engagement of the reverse brake 32, and therefore the drum rotation estimated value NDRUM' can be estimated. Then, it is possible to estimate the turbine rotation estimated value NTBN′ based on the alignment chart as usual with the drum rotation speed NDRUM=0. If the primary speed NPRI is unknown, the variator 4 is fixed to the lowest speed ratio in the R range, so the estimated primary speed NPRI' is estimated from the lowest speed ratio of the variator 4 and the secondary speed NSEC. It is possible to Then, it is possible to estimate the turbine rotation estimated value NTBN' based on the primary rotation estimated value NPRI' and the reverse gear ratio (=R gear ratio) of the planetary gear (double pinion type planetary gear 30).

(4) The turbine rotation estimation means (turbine rotation estimation unit 80) replaces the drum rotation speed NDRUM with the primary rotation speed NPRI when the forward clutch 31 is engaged and the drum rotation speed NDRUM is unknown while the vehicle is stopped. The drum rotation estimated value NDRUM' is set, and the turbine rotation estimated value NTBN' is calculated by the drum rotation estimated value NDRUM' and the detection value from the primary rotation sensor 90,
When the forward clutch 31 is engaged while the vehicle is stopped and the primary rotation speed NPRI is unknown, the primary rotation speed NTPRI is set to the primary rotation estimated value NPRI' in which the primary rotation speed NPRI is replaced with zero. It is calculated by the value NPRI′ and the detection value from the drum rotation sensor 96.
Therefore, when the forward clutch 31 is engaged and the drum rotation speed NDRUM or the primary rotation speed NPRI is unknown while the vehicle is stopped, the unknown drum rotation estimated value NDRUM' or primary rotation estimated value NPRI' and the turbine rotation estimated value NTBN are unknown. 'Can be calculated.
That is, since the forward clutch 31 is stopped in the engaged state, the drum rotation speed NDRUM=primary rotation speed NPRI=0. Therefore, it is possible to estimate the drum rotation estimated value NDRUM' or the primary rotation estimated value NPRI', and it is possible to estimate the turbine rotation estimated value NTBN' based on the alignment chart as usual.

(5) The turbine rotation estimation means (turbine rotation estimation unit 80) replaces the drum rotation speed NDRUM with zero and estimates the drum rotation when the reverse brake 32 is engaged and the drum rotation speed NDRUM is unknown while the vehicle is stopped. As the value NDRUM', the turbine rotation estimated value NTBN' is calculated by the drum rotation estimated value NDRUM' and the detection value from the primary rotation sensor 90,
When the reverse brake 32 is engaged and the primary rotation speed NPRI is unknown while the vehicle is stopped, the primary rotation speed NPRI is replaced with zero to set the primary rotation estimated value NPRI', and the turbine rotation estimated value NTBN' is set to the primary rotation estimation. It is calculated by the value NPRI′ and the detection value from the drum rotation sensor 96.
Therefore, when the reverse brake 32 is engaged and the drum speed NDRUM or the primary speed NPRI is unknown while the vehicle is stopped, the unknown drum rotation estimated value NDRUM' or primary rotation estimated value NPRI' and the turbine rotation estimated value NTBN are unknown. 'Can be calculated.
That is, when the drum rotation speed NDRUM is unknown, it is supposed that the drum rotation speed NDRUM=0 by the engagement of the reverse brake 32, and therefore the drum rotation estimated value NDRUM' can be estimated. Then, it is possible to estimate the turbine rotation estimated value NTBN′ based on the alignment chart as usual with the drum rotation speed NDRUM=0. When the primary rotation speed NPRI is unknown, the reverse rotation brake 32 is engaged and the vehicle is stopped, so that the primary rotation speed NPRI should be 0. Therefore, it is possible to estimate the primary rotation estimated value NPRI'. Then, it is possible to estimate the turbine rotation estimated value NTBN′ based on the alignment chart as usual with the primary rotation speed NPRI=0.

The control device for the continuously variable transmission according to the present invention has been described above based on the embodiments. However, the specific configuration is not limited to this embodiment, and design changes and additions are allowed without departing from the gist of the invention according to each claim of the claims.

In the example, the forward/reverse switching mechanism 3 has the double pinion type planetary gear 30, the forward clutch 31, and the reverse brake 32. However, the forward/reverse switching mechanism may be an example having a single pinion type planetary gear, a forward clutch and a reverse brake. In the case of the double pinion type planetary gear, the three rotating members S, C and R are arranged on the horizontal axis of the nomographic chart in the order of S→R→C (1-α):α, while the single pinion type In the case of a planetary gear, the three rotating members S, C, and R are different in that they are arranged on the horizontal axis of the alignment chart in the order of S→C→R at a ratio of 1:α.

In the embodiment, an example in which the control device of the present invention is applied to an engine vehicle equipped with a belt type continuously variable transmission CVT as an automatic transmission has been shown. However, the control device of the present invention may be applied to a vehicle equipped with a continuously variable transmission mechanism with an auxiliary transmission. Further, the vehicle to be applied is not limited to an engine vehicle, but can be applied to a hybrid vehicle having an engine and a motor as a driving source for traveling, an electric vehicle having a motor as a driving source for traveling, and the like.

Claims (6)

1. A torque converter connected to the drive source for traveling, a forward/reverse switching mechanism connected to the torque converter, a continuously variable transmission mechanism connected to the forward/reverse switching mechanism, and a transmission controller,
   The forward/reverse switching mechanism has a planetary gear, a forward clutch, and a reverse brake, the continuously variable transmission mechanism has a belt spanned between a primary pulley and a secondary pulley, and the transmission controller has the forward/backward movement. A control device for a continuously variable transmission that executes control using turbine speed information input to a forward switching mechanism,
   A turbine rotating shaft that connects the turbine runner of the torque converter and the sun gear of the planetary gear,
   A carrier and a ring gear of the planetary gear connected via the forward clutch,
   A drum rotation sensor for detecting the number of rotations of a drum member connected to the ring gear;
   A primary rotation sensor that detects the number of rotations of a primary rotation shaft that connects the carrier of the planetary gear and the primary pulley;
   Turbine rotation estimation means for calculating a turbine rotation estimation value of the turbine rotation shaft based on detection values of the drum rotation sensor and the primary rotation sensor,
   The turbine rotation estimation means, when the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown, a running/stopped state, an engagement/release state of the forward clutch and the reverse brake, the continuously variable transmission mechanism. Of at least two of the gear ratios, the estimated rotation speed of the unknown detected value is estimated, and the estimated turbine rotation speed is calculated by the estimated rotation speed estimated value and the other sensor detection value.
   Control device for continuously variable transmission.
2. The control device for a continuously variable transmission according to claim 1,
   The turbine rotation estimation means, while traveling, when the forward clutch is in the engaged state, and the drum rotation speed is unknown, sets the drum rotation estimation value by replacing the drum rotation speed with the primary rotation speed, and the turbine rotation estimation value. Is calculated by the drum rotation estimated value and the detection value from the primary rotation sensor,
   During traveling, when the forward clutch is in the engaged state, and if the primary rotation speed is unknown, the primary rotation speed is set to the primary rotation estimated value by replacing the primary rotation speed with the drum rotation speed, and the turbine rotation estimated value is set to the primary rotation estimated value. And calculated by the detection value from the drum rotation sensor,
   Control device for continuously variable transmission.
3. A control device for a continuously variable transmission according to claim 1 or 2,
   The turbine rotation estimation means, during traveling, when the reverse brake is in the engaged state, and when the drum rotation speed is unknown, replaces the drum rotation speed with zero to set the drum rotation estimated value, and the turbine rotation estimated value, Calculated by the drum rotation estimated value and the detection value from the primary rotation sensor,
   During traveling, when the reverse brake is in the engaged state, and when the primary rotation speed is unknown, the primary rotation speed is the primary rotation estimated value calculated from the lowest speed ratio and the secondary rotation speed of the continuously variable transmission mechanism, The turbine rotation estimated value is calculated by a primary rotation estimated value and a detection value from the drum rotation sensor,
   Control device for continuously variable transmission.
4. A control device for a continuously variable transmission according to any one of claims 1 to 3,
   The turbine rotation estimation means, while the vehicle is stopped, when the forward clutch is in the engaged state, and the drum rotation speed is unknown, sets the drum rotation estimation value by replacing the drum rotation speed with the primary rotation speed, and the turbine rotation estimation value. Is calculated by the drum rotation estimated value and the detection value from the primary rotation sensor,
   While the vehicle is stopped, the forward clutch is in the engaged state, and, if the primary rotation speed is unknown, the primary rotation speed is replaced with a primary rotation estimated value, and the turbine rotation estimated value is the primary rotation estimated value and the turbine rotation estimated value. Calculated with the detection value from the drum rotation sensor,
   Control device for continuously variable transmission.
5. A control device for a continuously variable transmission according to any one of claims 1 to 4,
   The turbine rotation estimation means, while the vehicle is stopped, and the reverse brake is in a fastening state, and when the drum rotation speed is unknown, replaces the drum rotation speed with zero to set the drum rotation estimated value, and the turbine rotation estimated value, Calculated by the drum rotation estimated value and the detection value from the primary rotation sensor,
   While the vehicle is stopped, when the reverse brake is in the engaged state and the primary rotation speed is unknown, the primary rotation speed is replaced with zero to obtain the primary rotation estimated value, and the turbine rotation estimated value is set to the primary rotation estimated value and the drum. Calculated by the detected value from the rotation sensor,
   Control device for continuously variable transmission.
6. A torque converter connected to the drive source for traveling, a forward/reverse switching mechanism connected to the torque converter, a continuously variable transmission mechanism connected to the forward/reverse switching mechanism, and a transmission controller,
   The forward/reverse switching mechanism has a planetary gear, a forward clutch, and a reverse brake, the continuously variable transmission mechanism has a belt spanned between a primary pulley and a secondary pulley, and the transmission controller has the forward/backward movement. The control using the turbine speed information input to the forward switching mechanism is executed,
   A turbine rotating shaft that connects the turbine runner of the torque converter and the sun gear of the planetary gear,
   A carrier and a ring gear of the planetary gear connected via the forward clutch,
   A drum rotation sensor for detecting the number of rotations of a drum member connected to the ring gear;
   A primary rotation sensor that detects the number of rotations of a primary rotation shaft that connects the carrier of the planetary gear and the primary pulley;
   A control method for a continuously variable transmission having:
   As the turbine rotation speed information, a turbine rotation estimated value of the turbine rotation shaft is calculated based on detection values of the drum rotation sensor and the primary rotation sensor,
   If the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown, the running/stopped state, the engagement/release state of the forward clutch and the reverse brake, the gear ratio of the continuously variable transmission mechanism, At least two are used to estimate the rotation speed of the unknown detection value, and the turbine rotation estimation value is calculated by the estimated rotation estimation value and the other sensor detection value,
   Control method for continuously variable transmission.

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