JP6913258B2 - Control device and control method for continuously variable transmission - Google Patents

Description

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 when a turbine sensor of an automatic transmission fails (see, for example, Patent Document 1). This conventional device normally uses a turbine sensor to perform high-precision shift control and line pressure control, and when the turbine sensor fails, estimates and calculates the turbine speed using input information other than the turbine sensor. When shifting is not in progress, the input rotation speed of the automatic transmission is calculated from the vehicle speed signal and the gear ratio. When shifting is in progress, the engine torque map characteristics are used to obtain the input torque (pump torque) of the torque converter, and further, the input torque of the automatic transmission and the input rotation speed of the automatic transmission are estimated and obtained. Here, the auxiliary torque value is learned at the start of shifting to correct the auxiliary torque, and the torque due to the moment of inertia of the engine is corrected to achieve high accuracy of the input rotation 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, but a drum rotation sensor is provided on the drum of the forward / backward switching mechanism, and the turbine is based on the detection values of the drum rotation sensor and the primary pulley rotation sensor. In some cases, the number of revolutions of is estimated. In such a belt-type continuously variable transmission, if the primary rotation speed is unknown, the gear ratio is also unknown, so that the primary rotation speed cannot be estimated based on the gear ratio, and the turbine rotation speed cannot be estimated.

An object of the present invention is to ensure the 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 Unexamined Patent Publication No. 9-2106

The present invention includes a torque converter, a forward / backward switching mechanism, a continuously variable transmission mechanism, and a transmission controller, and the transmission controller executes control using turbine rotation speed information input to the forward / backward switching mechanism. It is a control device for continuously variable transmissions.
A turbine rotation shaft that connects the torque converter turbine runner and the planetary gear sun gear,
Planetary gear carriers and ring gears connected via a forward clutch,
A drum rotation sensor that detects the rotation speed of the drum member connected to the ring gear,
A primary rotation sensor that detects the number of rotations of the primary rotation shaft that connects the carrier of the planetary gear and the primary pulley,
It has a turbine rotation estimation means that calculates a turbine rotation estimation value of the turbine rotation shaft based on the detection values of the drum rotation sensor and the primary rotation sensor.
When the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown, the turbine rotation estimation means has a running / stopped state, a forward clutch and reverse brake engagement / release state, and a gear ratio of a continuously variable transmission mechanism. At least two are used to estimate the rotation speed of an unknown detected value, and the turbine rotation estimated value is calculated from the estimated rotation estimated value and the other sensor detected value.

Therefore, when the detected value of the drum rotation sensor or the detected value of the primary rotation sensor is unknown, it is possible to secure the acquisition of the turbine rotation information by estimation.

It is an overall system diagram which shows the drive system and the control system of the engine vehicle to which the control device of the continuously variable transmission of an Example is applied. It is a shift schedule diagram which shows an example of the D range stepless shift schedule used when the stepless shift control in an automatic shift mode is executed by a variator. It is a schematic block diagram which shows the control device of the Example which performs the control using the turbine rotation speed information in a CVT control unit. It is a flowchart which shows the flow of the turbine rotation estimate value calculation processing executed in the turbine rotation estimation part of a CVT control unit. It is a collinear diagram of the forward / backward switching mechanism which shows the scene which prohibits the abnormality determination of a drum rotation sensor and a primary rotation sensor. It is a figure which shows the planetary gear, the forward clutch, the reverse brake, the turbine rotation sensor, and the primary rotation sensor in the forward / backward switching mechanism of the comparative example. It is a collinear diagram of the forward / backward switching mechanism which shows the calculation process of the turbine rotation estimate value when both the detection value of a drum rotation sensor and the detection value of a primary rotation sensor can be used. It is a collinear diagram of the forward / backward switching mechanism showing the calculation process of the turbine rotation estimated value when the detected value of the drum rotation sensor or the detected value of the primary rotation sensor is unknown while the forward clutch (FWD / C) is engaged and running. .. It is a collinear diagram of the forward / backward switching mechanism which shows the calculation process of the turbine rotation estimate 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. .. Forward / backward movement showing calculation processing of turbine rotation estimation value when the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown during the release running of the forward clutch (FWD / C) and reverse brake (REV / B). It is a collinear diagram of a switching mechanism. It is a collinear diagram of the forward / backward switching mechanism showing the calculation process of the turbine rotation estimated value when the detected value of the drum rotation sensor or the detected value of the primary rotation sensor is unknown while the forward clutch (FWD / C) is engaged and stopped. .. It is a collinear diagram of the forward / backward switching mechanism showing the calculation process of the turbine rotation estimated value when the detected value of the drum rotation sensor or the detected value of the primary rotation sensor is unknown while the reverse brake (REV / B) is engaged and stopped. .. Forward / backward movement showing calculation processing of turbine rotation estimation 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) and reverse brake (REV / B) are released and stopped. It is a collinear diagram of a switching mechanism.

Hereinafter, a mode for implementing the control device for the continuously variable transmission of the present invention will be described with reference to the examples 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 composed of a torque converter, a forward / backward switching mechanism, a variator, and a final deceleration mechanism. Hereinafter, the configuration of the embodiment will be described separately for the “overall system configuration”, the “control device configuration”, and the “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 the control device of the continuously variable transmission of the embodiment is applied. Hereinafter, the overall system configuration will be described with reference to FIG.

As shown in FIG. 1, the drive system of the engine vehicle includes an engine 1, a torque converter 2, a forward / backward switching mechanism 3, a variator 4, a final deceleration 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 / backward switching mechanism 3, a variator 4, and a final deceleration 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 controlling the output torque by operating the accelerator 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, fuel cut control is executed when the vehicle travels on the coast by releasing the accelerator foot.

The torque converter 2 is a starting element by a fluid coupling having a torque amplification function and a torque fluctuation absorption function. It has a lockup clutch 20 capable of directly connecting an engine output shaft 11 (= torque converter input shaft) and a turbine rotation shaft 21 (= torque converter output shaft) 21 when a torque amplification function or a torque fluctuation absorption function is not required. The torque converter 2 includes a pump impeller 23, a turbine runner 24, and a stator 26 as components. The pump impeller 23 is connected to the engine output shaft 11 via a converter housing 22. The turbine runner 24 is connected to the turbine rotation shaft 21. The stator 26 is provided in the transmission case via a one-way clutch 25.

The forward / backward switching mechanism 3 is a mechanism that switches the input rotation direction to the variator 4 between a forward rotation direction during forward travel and a reverse rotation direction during reverse travel. The forward / backward switching mechanism 3 includes a double pinion type planetary gear 30, a forward clutch 31 with a plurality of clutch plates, and a reverse brake 32 with a plurality of brake plates. The forward clutch 31 is hydraulically engaged by the forward clutch pressure Pfc when a 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 travel 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 has a primary pulley 42, a secondary pulley 43, and a belt 44, and continuously changes the gear ratio (ratio of variator input rotation to variator output rotation) by changing the belt contact diameter. It has a mechanical function. The primary pulley 42 is composed of a fixed pulley 42a and a slide pulley 42b 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. do. The secondary pulley 43 is composed of a fixed pulley 43a and a slide pulley 43b arranged coaxially with the secondary rotation shaft 41 (= variator output shaft), and the slide pulley 43b slides by the secondary pressure Psec guided to the secondary pressure chamber 46. do. The belt 44 is hung on the V-shaped sheave surface of the primary pulley 42 and the V-shaped sheave surface of the secondary pulley 43. The belt 44 is formed of two sets of laminated rings in which a large number of annular rings are stacked from the inside to the outside and a punched plate material, and a large number of elements attached by sandwiching the two sets of laminated rings in an annular manner. It is composed of 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 pins 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, gives a differential function, and transmits the differential function to the left and right drive wheels 6 and 6. As a reduction gear mechanism, the final reduction gear 5 includes 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 at the outer peripheral position of the differential case. It has a gear 55 and. Then, as the differential gear mechanism, it has a differential gear 56 interposed between the left and right drive shafts 51 and 51.

As shown in FIG. 1, the control system of the engine vehicle includes a hydraulic control unit 7, a CVT control unit 8 (abbreviated as "CVTCU"), and an engine control unit 9 (abbreviated as "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 applies a primary pressure Ppri guided to the primary pressure chamber 45, a secondary pressure Psec guided to the secondary pressure chamber 46, a forward clutch pressure Pfc to the forward clutch 31, a 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 in combination. 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. Each solenoid valve 72, 73, 74, 75, 76 performs a pressure adjusting operation according to a control command value (instructed current) output from the CVT control unit 8.

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

The primary pressure solenoid valve 73 adjusts the pressure reduction to the commanded primary pressure Ppri with the line pressure PL as the original pressure according to the primary pressure command value output from the CVT control unit 8. The secondary pressure solenoid valve 74 adjusts the pressure reduction to the secondary pressure Psec commanded with the line pressure PL as the original pressure according to the secondary pressure command value output from the CVT control unit 8.

The select solenoid valve 75 adjusts the pressure reduction to the forward clutch pressure Pfc or the backward brake pressure Prb commanded with the line pressure PL as the main pressure according to the forward clutch pressure command value or the reverse brake pressure command value output from the CVT control unit 8. do.

The lockup pressure solenoid valve 76 adjusts the pressure to the LU indicated pressure Pl that engages / slips / releases the lockup clutch 20 according to the indicated current Alu output from the CVT control unit 8.

The CVT control unit 8 performs line pressure control, shift control, forward / backward switching control, lockup control, and the like. In the line pressure control, a command value for obtaining a target line pressure according to the accelerator opening or the like is output to the line pressure solenoid valve 72. In 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 / backward switching control, a command value for controlling engagement / release 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, the instruction current Alu that controls the LU instruction pressure Pl that engages / engages / releases the lockup clutch 20 is output to the lockup pressure solenoid valve 76.

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, and the like is input.

Sensor information from the engine rotation sensor 12, the accelerator opening sensor 14, and the like is input to the engine control unit 9. When the CVT control unit 8 requests the engine rotation information and the accelerator opening information from the engine control unit 9, the CVT control unit 8 receives the information of the engine speed NENG and the accelerator opening APO via the CAN communication line 13. 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 amount control and the ignition timing retard control.

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

The "D range shift mode" is an automatic shift mode in which the gear ratio is automatically and steplessly changed according to the driving state of the vehicle. The shift control in the "D range shift mode" is performed by the operating point on the D range continuously variable transmission 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 rotation speed NPRI *. Then, the actual primary rotation speed NPRI from the primary rotation speed sensor 90 is controlled by feedback control of the pulley oil pressure to match the target primary rotation speed NPRI *. The gear ratio is represented by the slope of the gear ratio line drawn from the zero operating point, as is clear from the lowest gear ratio line and the highest gear ratio line of the D range continuously variable transmission schedule. Therefore, determining the target primary rotation speed NPRI * based on the operating point (VSP, APO) determines the target gear ratio of the variator 4.

That is, as shown in FIG. 2, the D-range continuously variable transmission schedule used in the "D-range continuously variable transmission mode" has a gear ratio range based on the lowest gear ratio and the highest gear ratio according to the operating point (VSP, APO). It is set to change the gear ratio steplessly within the range. For example, when the vehicle speed VSP is constant, when the accelerator is depressed, the target primary rotation speed NPRI * rises and shifts in the downshift direction, and when the accelerator return operation is performed, the target primary rotation speed NPRI * decreases and rises. Shift in the shift direction. When the accelerator opening APO is constant, the gear shifts in the upshift direction when the vehicle speed VSP increases, and shifts in the downshift direction when the vehicle speed VSP decreases.

[Control device configuration]
FIG. 3 shows a control device of an embodiment in which control using turbine speed information is executed in the CVT control unit 8. Hereinafter, the outline 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 is an engine 1 (driving drive source), a torque converter 2, a forward / backward switching mechanism 3, and a variator 4 (continuously variable transmission mechanism). A final deceleration mechanism 5 and a drive wheel 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, and a secondary pressure solenoid valve 74. , Select solenoid valve 75 and. 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, and the like is input to the CVT control unit 8. Information from the engine rotation sensor 12, the accelerator opening sensor 14, and the like 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, self-diagnosis function, etc. as controls using the turbine rotation speed information. Is referenced.

The forward / backward 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 rotation members whose rotation speed relationship is defined by a linear characteristic line in a collinear diagram. The forward / backward 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 connecting the engine 1 and the pump impeller 23 of the torque converter 2 is the engine 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) instead of being unable to arrange the "turbine rotation sensor" that detects the rotation of the turbine rotation shaft 21 on the layout. The rotation speed of the drum member 33 (= ring gear R) is the drum rotation speed NDRUM. The reverse brake 32 is arranged 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 estimation 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. That is, since the "turbine rotation sensor" is not provided, the turbine rotation speed information is estimated and calculated based on the detection values of the drum rotation sensor 96 and the primary rotation sensor 90 instead of the detection values from the turbine rotation sensor. The 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 rotation estimation value and the other sensor detection value. calculate. At this time, the rotation estimation value is estimated using at least two of the traveling / 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 turbine rotation estimated value NTBN', the front clutch 31 is engaged, the reverse brake 32 is engaged, and the forward clutch 31 and the reverse brake 32 are released during traveling. Then, even when the vehicle is stopped, the scene is divided into a scene in which the forward clutch 31 is engaged, a scene in which the reverse brake 32 is engaged, and a scene in which the forward clutch 31 and the reverse brake 32 are released.

That is, the turbine rotation estimated value NTBN'is divided into each of the six scenes, and the detection value of the drum rotation sensor 96 is unknown and the detection value of the primary rotation sensor 90 is unknown for each scene. It is calculated separately from. Regarding the transient scene of engagement → release of the forward clutch 31 and the reverse brake 32 or the transient scene of release → engagement, the turbine rotation speed information in the three scenes is switched according to the range position. Further, when the rotation restraint condition is not determined in the co-line diagram in the release scene of the forward clutch 31 and the reverse brake 32, for example, the turbine rotation estimated value NTBN'= engine without calculating the turbine rotation estimated value NTBN'. Estimate by assuming the turbine rotation estimate NTBN', such as the rotation speed NENG.

[Turbine rotation estimate calculation processing configuration]
FIG. 4 shows the flow of the turbine rotation estimation value calculation process 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, the NO determination in S1, or the NO determination in S2, it is determined whether or not the precondition is satisfied. If YES (prerequisite condition is satisfied), the process proceeds to S2, and if NO (precondition is not satisfied), the judgment of S1 is repeated.

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

In S2, following the YES determination in S1, it is determined whether or not the scene is other than the sensor abnormality determination prohibition scene. If YES (other than the sensor abnormality determination prohibited scene), the process proceeds to S3, and if NO (sensor abnormality determination prohibited scene), the process returns to S1.

Here, the "sensor abnormality determination prohibition scene" is a scene in which the drum rotation speed NDRUM is not detected by the drum rotation speed sensor 96 even in a normal state, or a drum rotation speed NDRUM is low rotation speed and the primary rotation speed NPRI is low rotation speed. Refers to the scene.

The specific scenes of the “sensor abnormality determination prohibition scene” are the following scenes (1) to (7), which correspond to (1) to (7) shown in FIG. The forward clutch 31 is referred to as "FWD / C", and the reverse brake 32 is referred to as "REV / B".
(1) The vehicle is stopped or idle-stopped when FWD / C or REV / B is concluded (however, it is out of the detection area because the primary rotation is not detected).
(2) Moving forward with REV / B conclusion.
(3) The REV / B is concluded and the vehicle is moving backward, and the REV / B is not concluded and the vehicle is moving backward.
(4) REV / B is not concluded and is moving backward.
(5) REV / B is not concluded and is moving backward.
(6) Moving forward without REV / B fastening (when the turbine speed is 0 rpm due to the worst engine stall, it is out of the detection range on the planet).
(7) The turbine speed rotates in the reverse direction without the REV / B being engaged (engine 1 does not rotate in the reverse direction).

In S3, following the YES determination in S2, it is determined whether or not the detection value of the drum rotation sensor 96 or the detection value of the primary rotation sensor 90 is unknown. If YES (one detected value is unknown), the process proceeds to S5, and if NO (both detected values are clear), the process proceeds to S4.

Here, to determine whether the sensor detection value is unknown, a disconnection abnormality is determined for each of the drum rotation sensor 96 and the primary rotation sensor 90, and the disconnection abnormality continues to output zero rotation speed even though the drum rotation sensor 96 is rotating. Is determined, the sensor detection value is treated as unknown.

In S4, following the NO judgment in S3, the turbine rotation speed NDRUM from the drum rotation sensor 96, the primary rotation speed NPRI from the primary rotation sensor 90, and the turbine rotation speed estimated value NTBN'by the rotation speed relationship in the co-line diagram are obtained. Calculate and proceed to return.

Here, in the case of the double pinion type planetary gear 30, if the rotation speeds of two rotating members of the sun gear S, the carrier C, and the ring gear R are known, the rotation speeds of the remaining one rotating member are 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 speed estimated value NTBN'(= sun gear S rotation speed) ) Is calculated by both rotation speeds NDRUM and NPRI and the gear ratio α.

In S5, following the YES determination in S3, it is determined whether or not the vehicle is running. If YES (running), proceed to S6, and if NO (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 is running if the vehicle speed VSP is equal to or higher than the stop determination threshold value VSP1, and that the vehicle is stopped if the vehicle speed VSP is less than the stop determination threshold value VSP1. NS.

In S6, following the YES determination in S5, it is determined whether or not the forward clutch 31 is in the engaged state. If YES (while driving with FWD / C), proceed to S8, and if NO (running with FWD / C released), proceed to S7. Here, the engaged state of the forward clutch 31 is determined, for example, by determining that the select range position is 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 (running with REV / B concluded), proceed to S9, and if NO (running with FWD / C and REV / B released), proceed to S10. Here, the engaged state of the reverse brake 32 is determined, for example, by determining that the select range position is the R range, which is the reverse travel range.

In S8, following the YES judgment 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, and the turbine is replaced. Calculate the rotation estimate NTBN'and proceed to return. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation speed sensor 90, since the forward clutch 31 is in the engaged state, the primary rotation speed NPRI is replaced with the drum rotation speed NDRUM, the turbine rotation speed estimated value NTBN'is calculated, and the return is returned. move on.

In S9, following the YES judgment 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 is performed. Calculate the estimated NTBN'and proceed to return. When the primary rotation speed NPRI is unknown due to an abnormality of 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. Estimated by the lowest gear ratio and 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 proceeds to return.

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 speed estimated value NTBN'is regarded as the engine rotation speed NENG. Then, the drum rotation speed NDRUM is calculated from the turbine rotation speed estimated value NTBN'(= NENG) and the primary rotation speed NPRI on a collinear diagram, and the process proceeds to return. When the primary rotation speed NPRI is unknown due to an abnormality of the primary rotation sensor 90, the turbine rotation speed estimated value NTBN'is regarded as the engine rotation speed NENG. Then, the primary rotation speed NPRI is calculated from the turbine rotation speed estimated value NTBN'(= NENG) and the drum rotation speed NDRUM on the collinear diagram, and the process proceeds to return. The primary rotation speed NPRI calculated in the co-line diagram is the primary rotation speed upper limit calculated from the lowest gear ratio of the secondary rotation speed NSEC and the variator 4, and the primary calculated from the highest gear ratio of the secondary rotation speed NSEC and the variator 4. It is limited by the lower limit of the number of revolutions.

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 (FWD / C is stopped), the process proceeds to S13, and if NO (FWD / C is released and stopped), the process proceeds to S12. Here, the engaged state of the forward clutch 31 is determined, for example, by determining that the select range position is 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 the vehicle is stopped with REV / B), proceed to S14, and if NO (when the vehicle is stopped with FWD / C and REV / B released), proceed to S15. Here, the engaged state of the reverse brake 32 is determined, for example, by determining that the select range position is the R range, which is the reverse travel range.

In S13, following the YES judgment 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 speed estimated value NTBN'is calculated, and the return is performed. Proceed to. When the primary rotation speed NPRI is unknown due to an abnormality of the primary rotation sensor 90, the primary rotation speed NPRI is replaced with NPRI = 0 (because the vehicle is stopped), the turbine rotation speed estimated value NTBN'is calculated, and the process proceeds to return.

In S14, following the YES judgment 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 return is returned. move on. When the primary rotation speed NPRI is unknown due to an abnormality of the primary rotation sensor 90, the primary rotation speed NPRI is replaced with NPRI = 0, the turbine rotation speed estimated value NTBN'is calculated, and the process 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 speed estimated value NTBN'is regarded as the engine rotation speed NENG. Then, the drum rotation speed NDRUM is calculated from the turbine rotation speed estimated value NTBN'(= NENG) and the primary rotation speed NPRI on a collinear diagram, and the process proceeds to return. When the primary rotation speed NPRI is unknown due to an abnormality of the primary rotation sensor 90, the turbine rotation speed 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), and the process proceeds to return.

Next, "background technology and issues" and "problem solving measures" will be explained. Then, the actions of the examples are "turbine rotation estimated value calculation action in a normal scene", "turbine rotation estimated value calculation action in a driving scene where the sensor detection value is unknown", and "a stop scene where the sensor detection value is unknown". It will be described separately in "Turbine rotation estimated value calculation action".

[Background technology and issues]
As shown in FIG. 6, the forward / backward switching mechanism of the comparative example is interposed between the torque converter and the 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 a member that connects the sun gear S and the carrier C of the double pinion type planetary gear. 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 connecting the carrier C and the primary pulley of the variator.

That is, in the case of the forward / backward switching mechanism of the comparative example shown in FIG. 6, the position of the forward clutch is the intermediate position of the member connecting the sun gear S and the carrier C. On the other hand, in the case of the forward / backward switching mechanism 3 of the embodiment shown in FIG. 3, the position of the forward clutch is set to the intermediate position of the drum member 33 connecting the ring gear R and the carrier C, and the torque converter aims at a compact layout. And the setting interval between the forward / backward 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 / backward switching mechanism of the comparative example cannot be provided in terms of layout. For this reason, 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 using the rotation speed relationship based on the co-line diagram of the double pinion type planetary gears. ..

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, the linear characteristic that defines the rotational relationship cannot be drawn on the collinear diagram. 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 collinear diagram.

[Problem solving measures]
The present inventor has clarified the scene in which the turbine rotation speed cannot be read correctly due to the change in the sensor position from the viewpoint of hardware, and refers to the turbine rotation speed and the derived signal from the viewpoint of software. Controls were extracted and their effects were confirmed. Then, even if only one of the drum rotation speed and the primary rotation speed is unknown, the turbine rotation speed information can be acquired.

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. A means was adopted in which the rotation speed of an unknown detected value was estimated, and the turbine rotation estimated value NTBN'was calculated 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 forward clutch 31 or the reverse brake 32 engaged state, and the gear ratio of the variator 4. The number of revolutions of the drum or the number of revolutions of the primary can be estimated using one. That is, the rotation speed of the carrier C of the forward / backward switching mechanism 3 becomes positive in the traveling state, and the rotation speed of the carrier C of the forward / backward switching mechanism 3 becomes zero in the stopped state. When the forward clutch 31 is engaged, the three elements S, C, and R of the forward / backward switching mechanism 3 have the same rotation speed. When the reverse brake 32 is engaged, the rotation speed of the ring gear R of the forward / backward 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 from the gear ratio of the variator 4, the rotation speed of the sun gear S (= turbine rotation speed) is determined.

Therefore, when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown, it is possible to secure the acquisition of the turbine rotation information by estimation. As a result, when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown, the control using the turbine rotation speed information referred to in many basic controls / functions can be continued. Specifically, for example, during execution of basic control / function such as lockup 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 Even if the value becomes unknown, the execution of basic control / function can be continued.

[Turbine rotation estimate calculation action in normal scene]
FIG. 7 shows a calculation process of the turbine rotation estimation 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 estimated value calculation operation in a normal scene in which 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 other than the sensor abnormality determination prohibition scene, and the detection value of the drum rotation sensor 96 and the detection value of the primary rotation sensor 90 can be used together, in the flowchart of FIG. 4, S1 → S2 → S3 → S4. → Proceed to return.

In S4, 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 collinear diagram. The formula (1) for the turbine rotation estimate NTBN'is
NTBN'＝ {NDRUM－NPRI (1-α)} / α… (1)
Is. However, the gear ratio α is obtained by the formula (number of teeth of sun gear S) ÷ (number of teeth of ring gear R).

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

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

When both the forward clutch 31 and the reverse brake 32 are in the released state, as shown in the collinear diagram characteristic F of FIG. 7, it corresponds to the size of the drum rotation speed NDRUM and the primary rotation speed NPRI, and the turbine rotation is estimated. The value NTBN'is calculated by the above equation (1).

[Turbine rotation estimated value calculation action in a driving scene where the sensor detection value is unknown]
The explanation of the turbine rotation estimated value calculation action is divided into (during traveling with the forward clutch engaged), (during traveling with the reverse brake engaged), and (during traveling with the forward clutch and the reverse brake released).

(While running with the forward clutch engaged)
FIG. 8 shows a calculation process of the turbine rotation estimated value NTBN'when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown during the engagement traveling of the forward clutch (FWD / C). Hereinafter, the turbine rotation estimated value calculation operation in the forward clutch engaged running scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 8.

The precondition is satisfied, the scene is other than the sensor abnormality determination prohibition 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 in the order of S1 → S2 → S3 → S5 → S6 → S8 → return.

In S8, when the drum rotation speed NDRUM is unknown due to an abnormality of the drum rotation sensor 96, the drum rotation speed NDRUM is replaced with the primary rotation speed NPRI, and the turbine rotation speed estimated value NTBN'is calculated. When the primary rotation speed NPRI is unknown due to an abnormality in the primary rotation speed sensor 90, the primary rotation speed NPRI is replaced with the drum rotation speed NDRUM, and the turbine rotation speed 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 has a broken line characteristic that passes through NDRUM = 0 as shown by ○ in FIG. 8 (a). Become. Therefore, the turbine rotation estimated value NTBN'is the same rotation speed as when traveling backward with the reverse brake 32 engaged. Therefore, the turbine rotation estimated value NTBN'is about 5% lower than the actual turbine rotation speed NTBN according to the collinear diagram shown in the solid line characteristics of FIG. 8 (a), and the input torque is estimated to be high. If the input torque is overestimated, the higher the input torque, the higher the oil pressure, which leads to deterioration of fuel efficiency.

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). It becomes a characteristic. Therefore, the turbine rotation estimated value NTBN'is about twice as high as the actual turbine rotation speed NTBN according to the collinear diagram shown in the solid line characteristics of FIG. 8 (b), and the input torque is underestimated. If the input torque is underestimated, the lower the input torque, the lower the oil pressure, 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 and the turbine rotation speed estimated value NTBN'is calculated as shown in the solid line characteristics 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 in the solid line characteristics in FIG. 8 (c).

Therefore, the calculated turbine speed estimate NTBN'consists with the actual turbine speed NTBN. In other words, unlike the case where it is left to the recognition of the CVT control unit 8, the input torque is not overestimated when the drum rotation speed NDRUM is unknown, and the deterioration of fuel consumption due to the increase in the oil pressure can be prevented. Further, unlike the case where it is left to the recognition of the CVT control unit 8, the input torque is not underestimated when the primary rotation speed NPRI is unknown, and the forward clutch 31 and the belt 44 slip by lowering the oil pressure. Can be prevented.

(While driving with reverse brake)
FIG. 9 shows a calculation process of the turbine rotation estimated value NTBN'when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown during the engaged running of the reverse brake (REV / B). Hereinafter, the turbine rotation estimated value calculation action in the reverse brake engaged running scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 9.

The precondition is satisfied, the scene is other than the sensor abnormality determination prohibition 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 in the order of S1 → S2 → S3 → S5 → S6 → S7 → S9 → return.

In S9, when the drum rotation speed NDRUM is unknown due to an abnormality of 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 of 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 by 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 has a broken line characteristic that passes through NDRUM = 0 as shown by ○ in FIG. 9 (a). Become. Therefore, the turbine rotation estimated value NTBN'is the same rotation speed as when traveling backward with the reverse brake 32 engaged. Therefore, the estimated turbine speed NTBN'is the same as the actual turbine speed NTBN shown in the collinear diagram shown in the solid line characteristics 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'is the cello rotation. That is, it is lower than the actual turbine speed NTBN according to the collinear diagram shown in the solid line characteristics of FIG. 9 (b), and the input torque is estimated to be high. If the input torque is overestimated, the higher the input torque, the higher the flood control, which leads to deterioration of fuel efficiency.

On the other hand, when the drum rotation speed NDRUM is unknown, the drum rotation speed NDRUM is replaced with NDRUM = 0 and the turbine rotation estimated value NTBN'is calculated as shown in the solid line characteristic of FIG. 9 (c). When the primary rotation speed NPRI is unknown, 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 by the primary rotation estimated value NPRI'and the reverse gear ratio (R gear ratio).

Therefore, the calculated turbine speed estimate NTBN'will match the actual turbine speed NTBN when the drum speed NDRUM is unknown. Then, the calculated turbine rotation speed estimated value NTBN'has improved consistency 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 of leaving it to the recognition of the CVT control unit 8, and deterioration of fuel consumption due to increasing the oil pressure can be prevented.

(During release of forward clutch and reverse brake)
FIG. 10 shows the turbine rotation estimated value NTBN when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown during the release running of the forward clutch (FWD / C) and the reverse brake (REV / B). 'Calculation processing is shown. Hereinafter, the turbine rotation estimated value calculation operation in the open running scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 10.

The precondition is satisfied, the scene is other than the sensor abnormality determination prohibition scene, and the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown during the release running of the forward clutch 31 and the reverse brake 32. In this case, in the flowchart of FIG. 4, the process proceeds in the order of S1 → S2 → S3 → S5 → S6 → S7 → S10 → return.

In S10, when the drum rotation speed NDRUM is unknown due to an abnormality of the drum rotation sensor 96, the turbine rotation speed estimation value NTBN'is regarded as the engine rotation speed NENG. Then, the drum rotation speed NDRUM is calculated from the turbine rotation speed estimated value NTBN'(= NENG) and the primary rotation speed NPRI in the collinear diagram. When the primary rotation speed NPRI is unknown due to an abnormality of the primary rotation sensor 90, the turbine rotation speed estimated value NTBN'is regarded as the engine rotation speed NENG. Then, the primary rotation speed NPRI is calculated from the turbine rotation speed estimated value NTBN'(= NENG) and the drum rotation speed NDRUM on the collinear diagram. The primary rotation speed NPRI calculated in the co-line diagram is calculated from the upper limit of the primary rotation speed calculated from the lowest gear ratio of the secondary rotation speed NSEC and the variator 4 and the highest gear ratio of the secondary rotation speed NSEC and the variator 4. It is limited by the lower limit of the primary rotation 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 has a broken line characteristic that passes through NDRUM = 0 as shown by ○ in FIG. 10 (a). Become. Therefore, the turbine rotation estimated value NTBN'is the same rotation speed as when traveling backward with the reverse brake 32 engaged. Therefore, the turbine rotation estimated value NTBN'is about 5% lower than the actual turbine rotation speed NTBN according to the collinear diagram shown in the solid line characteristics of FIG. 10 (a), and the input torque is estimated to be high. If the input torque is overestimated, the higher the input torque, the higher the oil pressure, which leads to deterioration of fuel efficiency.

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 turbine rotation estimated value NTBN'is about twice as high as the actual turbine rotation speed NTBN according to the collinear diagram shown in the solid line characteristics of FIG. 10 (b), and the input torque is underestimated. If the input torque is underestimated, the lower the input torque, the lower the oil pressure, which causes the forward clutch 31 and the belt 44 to slip.

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

Therefore, since the estimated turbine speed NTBN'is regarded as the engine speed NENG, it can be given at a value close to the actual turbine speed NTBN. Since there is no control to refer to the turbine rotation information while traveling in the N range by releasing the forward clutch 31 and the reverse brake 32, the control using the turbine rotation information due to an abnormality of the drum rotation sensor 96 or the primary rotation sensor 90 is used. Does not affect.

[Turbine rotation estimated value calculation action in a vehicle stop scene where the sensor detection value is unknown]
The explanation of the turbine rotation estimated value calculation action is divided into (when the forward clutch is engaged and stopped), (when the reverse brake is engaged and stopped), and (when the forward clutch and the reverse brake are released and stopped).

(While the forward clutch is engaged and stopped)
FIG. 11 shows a calculation process of the turbine rotation estimated value NTBN'when the detected value of the drum rotation sensor 96 or the detected 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 / stopping scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 11.

The precondition is satisfied, the scene is other than the sensor abnormality determination prohibition 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 in the order of S1 → S2 → S3 → S5 → S11 → S13 → return.

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

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

(While the reverse brake is fastened and stopped)
FIG. 12 shows a calculation process of the turbine rotation estimated value NTBN'when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown while the reverse brake (REV / B) is engaged and stopped. Hereinafter, the turbine rotation estimated value calculation action in the reverse brake engagement / stopping scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 12.

The precondition is satisfied, the scene is other than the sensor abnormality determination prohibition 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 in the order of S1 → S2 → S3 → S5 → S11 → S12 → S14 → return.

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

In this way, when the drum rotation speed NDRUM is unknown, the vehicle is stopped by engaging the reverse brake 32. Therefore, as shown in the solid line characteristics of FIG. 12, the turbine rotation speed is estimated as usual with the drum rotation speed NDRUM = 0. The value NTBN'(= 0) may be estimated. When the primary rotation speed NPRI is unknown, the vehicle is stopped with the reverse brake 32 engaged. Therefore, as shown in the solid line characteristics in FIG. 12, the turbine rotation speed estimated value NTBN'(as usual with the primary rotation speed NPRI = 0) = 0) may be estimated. It should be noted that when the vehicle is stopped with the reverse brake 32 fastened, the vehicle behavior in the control using the turbine rotation information does not affect the vehicle, unlike the vehicle in which the vehicle is running.

(While the forward clutch and reverse brake are released and stopped)
FIG. 13 shows the turbine rotation estimated value NTBN when the detected value of the drum rotation sensor 96 or the detected 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. 'Calculation processing is shown. Hereinafter, the turbine rotation estimated value calculation operation in the open stop scene in which the sensor detection value is unknown will be described with reference to FIGS. 4 and 13.

The precondition is satisfied, the scene is other than the sensor abnormality determination prohibition 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 in the order of S1 → S2 → S3 → S5 → S11 → S12 → S15 → return.

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

In this way, when the drum rotation speed NDRUM is unknown, the rotation speed of each rotation member S, C, R is determined by the degree of force balance when there is an accelerator operation, but the turbine rotation speed estimated value NTBN'is the engine rotation speed NENG. It can be basically estimated by considering it as. The drum rotation speed NDRUM can be basically estimated by a collinear diagram with the turbine rotation speed estimation value NTBN'(= NENG) and the primary rotation speed NPRI.

When the primary rotation speed NPRI is unknown, the rotation speed of each rotation member S, C, R is determined by the balance of force when there is an accelerator operation, but by considering the turbine rotation speed estimated value NTBN'as the engine rotation speed NENG It is basically estimable. Then, the primary rotation speed NPRI can be estimated because the vehicle is stopped and NPRI should be 0.

As described above, in the control device of 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 drive source (engine 1), a forward / backward switching mechanism 3 connected to the torque converter 2, and a continuously variable transmission mechanism (variator 4) connected to the forward / backward switching mechanism 3. ) And a transmission controller (CVT control unit 8).
The forward / backward switching mechanism 3 has a planetary gear (double pinion type planetary gear 30), a forward clutch 31 and a reverse brake 32, and the continuously variable transmission mechanism (variator 4) is mounted on the primary pulley 42 and the secondary pulley 43. A continuously variable transmission (belt type continuously variable transmission CVT) having a belt 44 to be passed, and a transmission controller (CVT control unit 8) executing control using the turbine rotation speed information input to the forward / backward switching mechanism 3. ) Control device
A turbine rotary shaft 21 that connects the turbine runner 24 of the torque converter 2 and the sun gear S of the planetary gear (double pinion type planetary gear 30), and
The carrier C and ring gear R of the planetary gear (double pinion type planetary gear 30) connected via the forward clutch 31,
A drum rotation sensor 96 that detects the rotation speed of the drum member 33 connected to the ring gear R, and
A primary rotation sensor 90 that detects the rotation speed of the primary rotation shaft 40 that connects the carrier C of the planetary gear (double pinion type planetary gear 30) and the primary pulley 42, and
It has a turbine rotation estimation means (turbine rotation estimation unit 80) that calculates a turbine rotation estimation 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.
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 a running / stopped state and a engaged / released state of the forward clutch 31 and the reverse brake 32. , At least two of the gear ratios of the stepless speed change mechanism (variator 4) are used to estimate the rotation speed of an unknown detected value, and the estimated rotation value and the other sensor detection value are used to estimate the rotation speed of the turbine. Calculate the rotation estimate NTBN'.
Therefore, when the detected value of the drum rotation sensor 96 or the detected value of the primary rotation sensor 90 is unknown, it is possible to secure the acquisition of the turbine rotation information by estimation.

(2) The turbine rotation estimation means (turbine rotation estimation unit 80) replaced the drum rotation NDRUM with the primary rotation NPRI when the forward clutch 31 was engaged and the drum rotation NDRUM was unknown during traveling. Drum rotation estimate NDRUM'and turbine rotation estimate NTBN',
Calculated by the drum rotation estimate NDRUM'and the value detected from the primary rotation sensor 90,
When the forward clutch 31 is engaged and the primary rotation speed NPRI is unknown during traveling, the primary rotation speed NPRI is replaced with the drum rotation speed NDRUM and the primary rotation speed estimation value NPRI'is used, and the turbine rotation speed estimation value NTBN'is set to It is calculated by the primary rotation estimated value NPRI'and the value detected 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 speed estimation value NDRUM'or primary rotation speed estimation value NPRI' and the turbine rotation speed estimation value NTBN 'Can be calculated.
That is, when the forward clutch 31 is in the engaged state, the forward gear ratio of the planetary gear (double pinion type planetary gear 30) becomes 1, so that the drum rotation speed NDRUM = primary rotation speed NPRI should be satisfied. 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 collinear diagram as usual.

(3) When the reverse brake 32 is engaged and the drum rotation speed NDRUM is unknown during traveling, the turbine rotation estimation means (turbine rotation estimation unit 80) replaces the drum rotation speed NDRUM with zero to estimate the drum rotation. The value NDRUM'is set, and the turbine rotation estimated value NTBN'is calculated by the drum rotation estimated value NDRUM'and the value detected from the primary rotation sensor 90.
When the reverse brake 32 is engaged and the primary rotation speed NPRI is unknown during running, the primary rotation speed NPRI is calculated by the lowest gear ratio of the stepless speed change mechanism (turbine 4) and the secondary rotation speed PSEC. Let the rotation estimated value NPRI', and the turbine rotation estimated value NTBN' be calculated by the primary rotation estimated value NPRI'and the value detected 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 speed estimation value NDRUM'or primary rotation speed estimation value NPRI' and the turbine rotation speed estimation value NTBN 'Can be calculated.
That is, when the drum rotation speed NDRUM is unknown, the drum rotation speed NDRUM should be 0 by fastening the reverse brake 32, so that the drum rotation estimated value NDRUM'can be estimated. Then, it is possible to estimate the turbine rotation estimated value NTBN'based on the collinear diagram as usual with the drum rotation speed NDRUM = 0. If the primary rotation speed NPRI is unknown, the variator 4 is fixed at the lowest gear ratio in the R range, so the primary rotation estimated value NPRI'is estimated by the lowest gear ratio of the variator 4 and the secondary rotation speed NSEC. It is possible to do. 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) replaced the drum rotation NDRUM with the primary rotation NPRI when the forward clutch 31 was engaged and the drum rotation NDRUM was unknown while the vehicle was stopped. The estimated drum rotation value NDRUM'is used, and the estimated turbine rotation value NTBN'is calculated by the estimated drum rotation value NDRUM'and the value detected from the primary rotation sensor 90.
When the forward clutch 31 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 speed estimation value NPRI', and the turbine rotation speed estimation value NTBN'is the primary rotation estimation value. It is calculated by the value NPRI'and the value detected 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 speed estimation value NDRUM'or primary rotation speed estimation value NPRI' and the turbine rotation speed estimation value NTBN '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 should be satisfied. 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 collinear diagram 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. The value NDRUM'is set, and the turbine rotation estimated value NTBN'is calculated by the drum rotation estimated value NDRUM'and the value detected from the primary rotation sensor 90.
When the vehicle is stopped, the reverse brake 32 is engaged, and the primary rotation speed NPRI is unknown, the primary rotation speed NPRI is replaced with zero to obtain the primary rotation speed estimated value NPRI', and the turbine rotation speed estimated value NTBN'is used as the primary rotation speed estimation. It is calculated by the value NPRI'and the value detected 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 while the vehicle is stopped, the unknown drum rotation speed estimation value NDRUM'or primary rotation speed estimation value NPRI' and the turbine rotation speed estimation value NTBN 'Can be calculated.
That is, when the drum rotation speed NDRUM is unknown, the drum rotation speed NDRUM should be 0 by fastening the reverse brake 32, so that the drum rotation estimated value NDRUM'can be estimated. Then, it is possible to estimate the turbine rotation estimated value NTBN'based on the collinear diagram as usual with the drum rotation speed NDRUM = 0. If the primary rotation speed NPRI is unknown, the primary rotation speed NPRI should be 0 because the vehicle is stopped by engaging the reverse brake 32. Therefore, it is possible to estimate the primary rotation estimate NPRI'. Then, it is possible to estimate the turbine rotation speed estimation value NTBN'based on the collinear diagram as usual with the primary rotation speed NPRI = 0.

The control device for the continuously variable transmission of the present invention has been described above based on the examples. However, the specific configuration is not limited to this embodiment, and design changes and additions are permitted as long as the gist of the invention according to each claim is not deviated from the claims.

In the embodiment, an example having a double pinion type planetary gear 30, a forward clutch 31, and a reverse brake 32 as the forward / backward switching mechanism 3 is shown. However, as the forward / backward switching mechanism, an example having a single pinion type planetary gear, a forward clutch, and a reverse brake may be used. In the case of a double pinion type planetary gear, the three rotating members S, C, and R are arranged on the horizontal axis of the co-line diagram in the order of S → R → C (1-α): α, whereas the single pinion type In the case of planetary gears, the difference is that the three rotating members S, C, and R are arranged on the horizontal axis of the co-line diagram in the order of S → C → R in a ratio of 1: α.

In the embodiment, an example is shown 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. 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 applicable vehicle is not limited to an engine vehicle, but can also be applied to a hybrid vehicle in which an engine and a motor are mounted as a driving drive source, an electric vehicle in which a motor is mounted as a driving drive source, and the like.

Claims (6)

It is provided with a torque converter connected to a driving drive source, a forward / backward switching mechanism connected to the torque converter, a continuously variable transmission mechanism connected to the forward / backward switching mechanism, and a transmission controller.
The forward / backward switching mechanism has a planetary gear, a forward clutch, and a reverse brake, the continuously variable transmission mechanism has a belt bridged between a primary pulley and a secondary pulley, and the transmission controller has the front / rear gear. It is a control device for a continuously variable transmission that executes control using the turbine rotation speed information input to the advance switching mechanism.
A turbine rotation shaft connecting the turbine runner of the torque converter and the sun gear of the planetary gear,
The carrier and ring gear of the planetary gear connected via the forward clutch,
A drum rotation sensor that detects the rotation speed of the drum member connected to the ring gear, and
A primary rotation sensor that detects the rotation speed of the primary rotation shaft that connects the carrier of the planetary gear and the primary pulley, and
It has a turbine rotation estimation means for calculating a turbine rotation estimation value of the turbine rotation shaft based on a detection value of the drum rotation sensor and the primary rotation sensor.
When the detection value of the drum rotation sensor or the detection value of the primary rotation sensor is unknown, the turbine rotation estimation means includes a running / stopped state, a engaged / released state of the forward clutch and the reverse brake, and the continuously variable transmission mechanism. The rotation speed of the unknown detected value is estimated using at least two of the gear ratios of the above, and the turbine rotation estimated value is calculated from the estimated rotation estimated value and the other sensor detected value.
Control device for continuously variable transmission. In the control device for the continuously variable transmission according to claim 1.
When the forward clutch is engaged and the drum rotation speed is unknown during traveling, the turbine rotation estimation means uses the drum rotation speed as a drum rotation estimation value by replacing the drum rotation speed with the primary rotation speed, and uses the turbine rotation estimation value. Is calculated by the estimated drum rotation value and the detected value from the primary rotation sensor.
When the forward clutch is engaged and the primary rotation speed is unknown during traveling, the primary rotation speed is replaced with the drum rotation speed to obtain a primary rotation estimated value, and the turbine rotation estimated value is used as the primary rotation estimated value. And the value detected from the drum rotation sensor.
Control device for continuously variable transmission. In the control device for the continuously variable transmission according to claim 1 or 2.
When the reverse brake is engaged and the drum rotation speed is unknown during traveling, the turbine rotation estimation means replaces the drum rotation speed with zero to obtain a drum rotation estimation value, and obtains the turbine rotation estimation value. Calculated from the estimated drum rotation and the value detected from the primary rotation sensor,
When the reverse brake is engaged and the primary rotation speed is unknown during traveling, the primary rotation speed is set as the primary rotation estimated value calculated from the lowest gear ratio and the secondary rotation speed of the continuously variable transmission mechanism. The turbine rotation speed estimation value is calculated from the primary rotation speed estimation value and the detection value from the drum rotation sensor.
Control device for continuously variable transmission. In the continuously variable transmission control device according to any one of claims 1 to 3.
When the forward clutch is engaged and the drum rotation speed is unknown while the vehicle is stopped, the turbine rotation estimation means uses a drum rotation estimation value in which the drum rotation speed is replaced with a primary rotation speed, and the turbine rotation estimation value is used. Is calculated by the estimated drum rotation value and the detected value from the primary rotation sensor.
When the vehicle is stopped, the forward clutch is engaged, and the primary rotation speed is unknown, the primary rotation speed is replaced with zero, and the turbine rotation estimation value is the primary rotation estimation value and the primary rotation speed estimation value. Calculated by the value detected from the drum rotation sensor,
Control device for continuously variable transmission. In the continuously variable transmission control device according to any one of claims 1 to 4.
When the vehicle is stopped, the reverse brake is engaged, and the drum rotation speed is unknown, the turbine rotation estimation means replaces the drum rotation speed with zero to obtain a drum rotation estimation value, and uses the turbine rotation estimation value as an estimated value. Calculated from the estimated drum rotation and the value detected from the primary rotation sensor,
When the vehicle is stopped, the reverse brake is engaged, 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 the primary rotation estimated value and the drum. Calculated by the value detected from the rotation sensor,
Control device for continuously variable transmission. It is provided with a torque converter connected to a driving drive source, a forward / backward switching mechanism connected to the torque converter, a continuously variable transmission mechanism connected to the forward / backward switching mechanism, and a transmission controller.
The forward / backward switching mechanism has a planetary gear, a forward clutch, and a reverse brake, the continuously variable transmission mechanism has a belt bridged between a primary pulley and a secondary pulley, and the transmission controller has the front / rear gear. Execute control using the turbine speed information input to the lead switching mechanism,
A turbine rotation shaft connecting the turbine runner of the torque converter and the sun gear of the planetary gear,
The carrier and ring gear of the planetary gear connected via the forward clutch,
A drum rotation sensor that detects the rotation speed of the drum member connected to the ring gear, and
A primary rotation sensor that detects the rotation speed of the primary rotation shaft that connects the carrier of the planetary gear and the primary pulley, and
It is a control method of a continuously variable transmission having
As the turbine rotation speed information, the turbine rotation estimated value of the turbine rotation shaft is calculated based on the detection values of the drum rotation sensor and the primary rotation sensor.
When the detected value of the drum rotation sensor or the detected value of the primary rotation sensor is unknown, among the running / stopped state, the engaged / released state of the forward clutch and the reverse brake, and the gear ratio of the continuously variable transmission mechanism. Using at least two, the rotation speed of the unknown detected value is estimated, and the turbine rotation estimated value is calculated from the estimated rotation estimated value and the other sensor detected value.
Control method for continuously variable transmission.

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