JP2015190550A - Control device of transmission for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To diagnose a failure of a line pressure sensor and a failure of a line pressure control circuit separately from each other.SOLUTION: A control device of a continuously variable transmission with an auxiliary transmission, includes: a line pressure control circuit disposed on a line pressure oil passage 111c from a mechanical oil pump 10 and regulating a line pressure PL; a lock-up oil pressure control circuit 112 which is disposed on a downstream position of the control circuit 111 and controls an oil pressure to a lock-up clutch 9; a line pressure sensor 44 for detecting the line pressure PL; and a transmission controller 12 outputting a coupling command of the lock-up clutch 9 to the lock-up oil pressure control circuit 112 when an engine speed N is a prescribed engine speed capable of controlling an oil pressure of the continuously variable transmission with the auxiliary transmission, or more, and when the line pressure PL detected by the sensor 44 is less than a prescribed line pressure, and determining whether the lock-up clutch 9 is operated or not.

Description

  The present invention relates to a control device for a vehicle transmission, which includes an engine, a transmission interposed between the engine and driving wheels, a mechanical oil pump driven by the engine, and a hydraulic sensor.

  Conventionally, as a failure diagnosis device of a hydraulic pressure detection device, each friction engagement element has a solenoid valve connected to a line pressure source and a drain, and a hydraulic sensor (line pressure sensor or the like) that detects actual hydraulic pressure to each friction engagement element. ), The supply hydraulic pressure to each friction engagement element is controlled to the target hydraulic pressure by the solenoid valve, and a failure of the hydraulic sensor is diagnosed based on the difference between the target hydraulic pressure and the actual hydraulic pressure. The failure diagnosis of the hydraulic sensor is permitted after the key switch is turned on and when a selection from the stop range to the travel range is detected, the solenoid valve is operated to perform precharge for failure diagnosis. Things are known. (For example, refer to Patent Document 1).

JP 2000-266176 A

  However, in the conventional failure diagnosis device for the hydraulic pressure detection device, even if the solenoid valve fails and no hydraulic pressure is supplied, the failure diagnosis of the hydraulic sensor is erroneously performed. For this reason, when a failure of the hydraulic sensor is diagnosed, there is a problem that it is unclear whether the solenoid valve has failed or the hydraulic sensor has failed.

  The present invention has been made paying attention to the above problem, and an object of the present invention is to provide a control device for a vehicle transmission capable of separately diagnosing a line pressure sensor failure and a line pressure control circuit failure.

In order to achieve the above object, a control apparatus for a vehicle transmission according to the present invention includes an engine, a transmission interposed between the engine and a drive wheel, and an intermediate between the engine and the transmission. A torque converter having a lockup clutch mounted thereon, a mechanical oil pump driven by the engine, a line pressure control circuit for adjusting a line pressure provided in an oil passage from the mechanical oil pump, and the line pressure control A lock-up hydraulic pressure control circuit that is provided at a downstream position of the circuit and controls the hydraulic pressure to the lock-up clutch, a line pressure sensor that detects the line pressure, and a line pressure system failure diagnosis unit.
The line pressure system failure diagnosing means is configured such that the line pressure detected by the line pressure sensor is less than a predetermined line pressure when the engine speed of the engine is equal to or higher than a predetermined engine speed capable of controlling the hydraulic pressure of the transmission. If so, an engagement command for the lockup clutch is output to the lockup hydraulic pressure control circuit, and it is determined whether or not the lockup clutch is operated.

Therefore, when the engine speed is equal to or higher than the predetermined engine speed and the line pressure detected by the line pressure sensor is less than the predetermined line pressure, a lockup clutch engagement command is output to the lockup hydraulic control circuit, It is determined whether or not the up clutch has been activated.
In other words, when the line pressure is regulated to a predetermined line pressure or higher by the line pressure control circuit, the lockup hydraulic control circuit locks even if the line pressure detected by the line pressure sensor is less than the predetermined line pressure. The hydraulic pressure to the up clutch can be controlled. At this time, when the lock-up clutch engagement command is output to the lock-up hydraulic control circuit and it is determined that the lock-up clutch has been operated, the line pressure control circuit has not failed, and a line pressure sensor failure is diagnosed. .
In addition, when the line pressure sensor is normal and the line pressure control circuit has not adjusted the line pressure to a predetermined line pressure or higher, the lockup hydraulic control circuit cannot control the hydraulic pressure to the lockup clutch. . At this time, even if the lock-up clutch engagement command is output to the lock-up hydraulic control circuit, it is determined that the lock-up clutch is inoperative. If it is determined in this way, a line pressure control circuit failure is diagnosed.
As a result, when the hydraulic control of the transmission is possible, the line pressure sensor failure and the line pressure control circuit failure can be diagnosed separately by determining whether the lockup clutch is operating or not.

1 is an overall system diagram showing a schematic configuration of a vehicle on which a continuously variable transmission with a sub-transmission (an example of a vehicle transmission) to which a control device of Example 1 is applied. FIG. 3 is a control block diagram illustrating a control system configuration centering on the transmission controller of the first embodiment. It is a shift map figure which shows an example of the shift map stored in the memory | storage device of the transmission controller of Example 1. FIG. It is a figure which shows the hydraulic circuit structure to the lockup clutch 9 among hydraulic control circuits. 5 is a flowchart 1 illustrating a flow of a coast stop-compatible transmission control process executed by the transmission controller according to the first embodiment. 6 is a flowchart 2 illustrating a flow of a coast stop-compatible transmission control process executed by the transmission controller according to the first embodiment. 6 is a flowchart 3 illustrating a flow of a coast stop-compatible transmission control process executed by the transmission controller according to the first embodiment. Coast stop control on / off of the vehicle of Example 1 CS / FLG, engine speed Ne, vehicle speed VSP, lockup clutch L / U, line pressure PL, high clutch oil pressure PH / C, low brake 6 is a time chart showing characteristics of clutch hydraulic pressure command value PL / B ^* and primary current command value PriSOL / I ^* .

  Hereinafter, the best mode for realizing a control device for a vehicle transmission according to the present invention will be described based on a first embodiment shown in the drawings.

First, the configuration will be described.
The control device of the continuously variable transmission with an auxiliary transmission (an example of a vehicle transmission) according to the first embodiment includes an “overall system configuration”, “a shift control configuration based on a shift map”, and “a hydraulic circuit configuration for a lockup clutch”. The description will be divided into “coast stop control configuration” and “coast stop-compatible transmission control configuration”.

[Overall system configuration]
FIG. 1 shows a schematic configuration of a vehicle on which a continuously variable transmission with a sub-transmission to which the control device of the first embodiment is applied, and FIG. 2 shows an internal configuration of a transmission controller. The overall system configuration will be described below with reference to FIGS.
In the following description, the “transmission ratio” of a transmission mechanism is a value obtained by dividing the input rotational speed of the transmission mechanism by the output rotational speed of the transmission mechanism. Further, “lowest speed ratio” means the maximum speed ratio of the speed change mechanism, and “highest speed ratio” means the minimum speed ratio of the speed change mechanism.

A vehicle equipped with the continuously variable transmission with the auxiliary transmission includes an engine 1 having a starter motor 15 for starting the engine as a power source. Output rotation of the engine 1 is transmitted through a torque converter 2 having a lock-up clutch 9, a reduction gear pair 3, a continuously variable transmission (hereinafter simply referred to as “transmission 4”), a final gear pair 5, and a final reduction gear 6. Is transmitted to the drive wheel 7. The final gear pair 5 is provided with a parking mechanism 8 that mechanically locks the output shaft of the transmission 4 during parking.
The vehicle also includes a mechanical oil pump 10 driven by the power of the engine 1 and a hydraulic control circuit 11 that regulates the discharge pressure from the mechanical oil pump 10 and supplies the pressure to each part of the transmission 4 and the lockup clutch 9. A transmission controller 12 that controls the hydraulic control circuit 11, an integrated controller 13, and an engine controller 14. Each configuration will be described below.

  The transmission 4 includes a belt-type continuously variable transmission mechanism (hereinafter referred to as “variator 20”) and an auxiliary transmission mechanism 30 provided in series with the variator 20. Here, “provided in series” means that the variator 20 and the subtransmission mechanism 30 are provided in series in the power transmission path. The auxiliary transmission mechanism 30 may be directly connected to the output shaft of the variator 20 as in this example, or may be connected via another transmission or power transmission mechanism (for example, a gear train).

  The variator 20 is a belt-type continuously variable transmission mechanism that includes a primary pulley 21, a secondary pulley 22, and a V-belt 23 that is wound around the pulleys 21 and 22. Each of the pulleys 21 and 22 is disposed with a fixed conical plate, a movable conical plate formed with a sheave surface facing the fixed conical plate, and forming a V groove between the fixed conical plate and the movable conical plate. A primary hydraulic cylinder 23a and a secondary hydraulic cylinder 23b are provided on the back surface of the plate to displace the movable conical plate in the axial direction. When the hydraulic pressure supplied to the primary hydraulic cylinder 23a and the secondary hydraulic cylinder 23b is adjusted, the width of the V groove changes, the contact radius between the V belt 23 and each pulley 21, 22 changes, and the transmission ratio vRatio of the variator 20 changes. Change steplessly.

  The subtransmission mechanism 30 is a transmission mechanism having two forward speeds and one reverse speed. The subtransmission mechanism 30 is connected to a Ravigneaux type planetary gear mechanism 31 in which two planetary gear carriers are coupled, and a plurality of rotating elements constituting the Ravigneaux type planetary gear mechanism 31, and a plurality of frictions that change their linkage state. Fastening elements (low brake 32, high clutch 33, reverse brake 34) are provided. When the hydraulic pressure supplied to each of the frictional engagement elements 32 to 34 is adjusted and the engagement / release state of each of the frictional engagement elements 32 to 34 is changed, the gear position of the auxiliary transmission mechanism 30 is changed. For example, if the low brake 32 is engaged and the high clutch 33 and the reverse brake 34 are released, the gear position of the subtransmission mechanism 30 is the first speed. When the high clutch 33 is engaged and the low brake 32 and the reverse brake 34 are released, the gear position of the subtransmission mechanism 30 becomes the second speed having a smaller gear ratio than the first speed. Further, if the reverse brake 34 is engaged and the low brake 32 and the high clutch 33 are released, the shift speed of the subtransmission mechanism 30 is reverse. In the following description, it is expressed that “the transmission 4 is in the low speed mode” when the shift speed of the auxiliary transmission mechanism 30 is the first speed, and “the transmission 4 is in the high speed mode” when the speed is the second speed. Express.

  The lock-up clutch 4 performs switching control between a lock-up state (engaged), an unlock-up state (release), and a slip lock-up state (slip engagement) according to the driving state and the vehicle state. This switching control and lock-up clutch engagement force control (lock-up clutch capacity control) in the lock-up state and slip lock-up state are performed in the torque converter supply pressure Pa in the front and rear chambers of the lock-up clutch on the transmission 4 side and the engine 1 side. And the differential pressure control between the torque converter release pressure Pr.

  As shown in FIG. 2, the transmission controller 12 includes a CPU 121, a storage device 122 including a RAM / ROM, an input interface 123, an output interface 124, and a bus 125 that interconnects them. .

  The input interface 123 includes an output signal of an accelerator opening sensor 41 for detecting an accelerator pedal depression degree (hereinafter referred to as “accelerator opening APO”), an input rotational speed of the transmission 4 (= the primary pulley 21 of the primary pulley 21). The output signal of the rotational speed sensor 42 (transmission rotational speed sensor) for detecting the rotational speed or the rotational speed of the rotational element of the transmission 4, hereinafter referred to as “primary rotational speed Npri”), the vehicle traveling speed (hereinafter referred to as “ Vehicle speed sensor 43 for detecting the vehicle speed VSP), output signal for the line pressure sensor 44 for detecting the line pressure of the transmission 4 (hereinafter referred to as “line pressure PL”), and the position of the select lever. An output signal of the inhibitor switch 45 is input.

  The storage device 122 stores a shift control program for the transmission 4 and a shift map (FIG. 3) used in the shift control program. The CPU 121 reads out and executes a shift control program stored in the storage device 122, performs various arithmetic processes on various signals input via the input interface 123, generates a shift control signal, and generates the generated shift control program. The control signal is output to the hydraulic control circuit 11 via the output interface 124. Various values used in the arithmetic processing by the CPU 121 and the arithmetic results are appropriately stored in the storage device 122.

The hydraulic control circuit 11 includes a plurality of flow paths and a plurality of hydraulic control valves. The hydraulic control circuit 11 switches a hydraulic pressure supply path by controlling a plurality of hydraulic control valves based on a shift control signal from the transmission controller 12. That is, the line pressure PL is adjusted from the discharge pressure generated by the mechanical oil pump 10, and the pulley pressure and the clutch pressure adjusted using the line pressure PL as the original pressure are supplied to each part of the transmission 4. Thereby, the gear ratio vRatio of the variator 20 and the gear position of the auxiliary transmission mechanism 30 are changed, and the transmission 4 is shifted.
Further, the torque converter pressure PT / C adjusted based on the oil discharged when adjusting the line pressure PL is supplied to the lockup clutch 9. Thereby, engagement / slip engagement / release of the lock-up clutch 9 is controlled.

  The integrated controller 13 performs integrated management of a plurality of in-vehicle controllers so that transmission control by the transmission controller 12 and engine control by the engine controller 14 are appropriately secured. The integrated controller 13 is connected to an in-vehicle controller such as the transmission controller 12 and the engine controller 14 via a CAN communication line 25 so that information can be exchanged.

  The engine controller 14 performs coast stop control for stopping the engine 1 after coast deceleration, idle stop control for stopping the engine 1 when the vehicle stops, engine start control using the starter motor 15, and the like. The engine controller 14 receives an output signal of an engine speed sensor 46 that detects the speed of the engine 1 (hereinafter referred to as “engine speed Ne”).

[Shift control configuration by shift map]
FIG. 3 shows an example of a shift map stored in the storage device 122 of the transmission controller 12. Hereinafter, a shift control configuration based on the shift map will be described with reference to FIG.

  The operating point of the transmission 4 is determined based on the vehicle speed VSP and the primary rotational speed Npri on the shift map shown in FIG. The slope of the line connecting the operating point of the transmission 4 and the zero point of the lower left corner of the transmission map is the overall transmission obtained by multiplying the transmission ratio of the transmission 4 (the transmission ratio vRatio of the variator 20 and the transmission ratio subRatio of the subtransmission mechanism 30). Ratio, hereinafter referred to as “through transmission ratio”). Similar to the shift map of the conventional belt-type continuously variable transmission, a shift line is set for each accelerator opening APO, and the shift of the transmission 4 is selected according to the accelerator opening APO. According to the shift line. For the sake of simplicity, FIG. 3 shows the full load line F / L (shift line when the accelerator opening APO = 8/8) and the partial line P / L (shift when the accelerator opening APO = 4/8). Line) and coast line C / L (shift line when accelerator opening APO = 0) are shown.

  When the transmission 4 is in the low speed mode, the transmission 4 has a low speed mode lowest line LL / L obtained by maximizing the transmission ratio vRatio of the variator 20, and a low speed mode obtained by minimizing the transmission ratio vRatio of the variator 20. It is possible to shift between the highest line LH / L. At this time, the operating point of the transmission 4 moves in the A region and the B region. On the other hand, when the transmission 4 is in the high speed mode, the transmission 4 has the highest speed line HL / L obtained by maximizing the transmission ratio vRatio of the variator 20 and the high speed obtained by minimizing the transmission ratio vRatio of the variator 20. It is possible to shift between the mode highest line HH / L. At this time, the operating point of the transmission 4 moves in the B region and the C region.

  The gear ratio of each gear stage of the sub-transmission mechanism 30 is the gear ratio corresponding to the low speed mode highest line LH / L (the low speed mode highest gear ratio) corresponding to the high speed mode lowest line HL / L ( It is set to be smaller than (high speed mode lowest gear ratio). Accordingly, the low speed mode ratio range LRE that is a range of the through speed ratio Ratio of the transmission 4 that can be taken in the low speed mode, and the high speed mode ratio range HRE that is a range of the through speed ratio Ratio of the transmission 4 that can be taken in the high speed mode. , Partially overlap. When the operating point of the transmission 4 is in the B region (overlapping region) between the high speed mode lowest line HL / L and the low speed mode highest line LH / L, the transmission 4 is in either the low speed mode or the high speed mode. The mode can also be selected.

  The transmission controller 12 refers to this shift map and sets the through speed ratio Ratio corresponding to the vehicle speed VSP and the accelerator opening APO (the driving state of the vehicle) as the ultimate through speed ratio DRatio. The reaching through speed ratio DRatio is a target value that the through speed ratio Ratio should finally reach in the operation state. Then, the transmission controller 12 sets a target through speed ratio tRatio, which is a transient target value for causing the through speed ratio Ratio to follow the reached through speed ratio DRatio with a desired response characteristic, and the through speed ratio Ratio is the target. The variator 20 and the subtransmission mechanism 30 are controlled so as to coincide with the through speed ratio tRatio.

  On the shift map, a mode switching up shift line MU / L (1 → 2 up shift line of the subtransmission mechanism 30) for performing the upshift of the subtransmission mechanism 30 is substantially on the low speed mode highest line LH / L. It is set to overlap. The through speed ratio Ratio corresponding to the mode switching up speed change line MU / L is substantially equal to the low speed mode highest speed ratio LH / L. Further, on the shift map, the mode switching down shift line MD / L (2 → 1 down shift line of the subtransmission mechanism 30) for performing the downshift of the subtransmission mechanism 30 is on the high-speed mode lowest line HL / L. It is set so as to be almost overlapped. The through speed ratio Ratio corresponding to the mode switching down speed change line MD / L is substantially equal to the high speed mode lowest speed ratio HL / L.

  When the operating point of the transmission 4 crosses the mode switching up transmission line MU / L or the mode switching down transmission line MD / L, that is, the target through speed ratio tRatio of the transmission 4 straddles the mode switching speed ratio mRatio. The transmission controller 12 performs the mode switching shift control when it is changed at or when it matches the mode switching gear ratio mRatio. In this mode switching shift control, the transmission controller 12 shifts the auxiliary transmission mechanism 30 and changes the transmission ratio vRatio of the variator 20 in a direction opposite to the direction in which the transmission ratio subRatio of the auxiliary transmission mechanism 30 changes. As described above, “cooperative control” for coordinating two shifts is performed.

  In the “cooperative control”, when the target through speed ratio tRatio of the transmission 4 crosses the mode switching up shift line MU / L from the B area side toward the C area side, or the mode switching up shift line from the B area side. When the MU / L coincides, the transmission controller 12 issues a 1 → 2 upshift determination, changes the gear position of the subtransmission mechanism 30 from the first speed to the second speed, and changes the gear ratio vRatio of the variator 20. The highest gear ratio is changed to the low gear ratio. Conversely, when the target through speed ratio tRatio of the transmission 4 crosses the mode switching down shift line MD / L from the B area side toward the A area side, or from the B area side to the mode switching down shift line MD / L. If they match, the transmission controller 12 issues a 2 → 1 downshift determination, changes the gear position of the subtransmission mechanism 30 from the second speed to the first speed, and changes the speed ratio vRatio of the variator 20 from the lowest speed ratio. Change to the gear ratio side.

  The reason for performing the “cooperative control” for changing the speed ratio vRatio of the variator 20 at the time of the mode change up shift or the mode change down shift is the change in the input rotational speed caused by the step of the through speed ratio Ratio of the transmission 4. This is because the driver's uncomfortable feeling can be suppressed, and the shift shock of the auxiliary transmission mechanism 30 can be reduced.

[Hydraulic circuit configuration to lock-up clutch]
Next, the hydraulic circuit configuration to the lockup clutch 9 will be described with reference to FIG.

  The lockup clutch 4 is provided in the torque converter 2, and the torque converter supply pressure Pa and the torque converter release pressure Pr to the front and rear chambers of the lockup clutch are based on the discharge pressure from the mechanical oil pump 10 driven by the engine 1. Created by the hydraulic control circuit 11. The hydraulic pressure control circuit 11 includes a line pressure control circuit 111 and a lockup hydraulic pressure control circuit 112.

  The line pressure control circuit 111 includes a pressure regulator valve 111a, a line pressure solenoid 111b, and a line pressure oil passage 111c (oil passage).

  The lockup hydraulic control circuit 112 includes a torque converter regulator valve 112a, a lockup control valve 112b, a lockup solenoid 112c, a torque converter oil passage 112d, a lubricating oil passage 112e, a supply pressure oil passage 112f, and a release. Pressure oil passage 112g. The lockup hydraulic pressure control circuit 112 is provided at a downstream position of the line pressure control circuit 111 as shown in FIG.

The pressure regulator valve 111a is a valve that regulates the line pressure PL from the pump discharge pressure. An operation signal pressure or the like created by the line pressure solenoid 111b acts on one end side of the pressure regulator valve 111a, and a feedback pressure acts on the other end side. The pressure regulator valve 111 a is provided in the line pressure oil passage 111 c (oil passage) from the mechanical oil pump 10. Further, the pressure regulator valve 111a discharges the oil discharged when adjusting the line pressure PL to the torque converter oil passage 112d.
The line pressure solenoid 111b is a solenoid that generates an operation signal pressure to the pressure regulator valve 111a using the pilot pressure Pp as an original pressure and a solenoid force based on an instruction value from the transmission controller 12 as an operation signal pressure.
Note that the line pressure oil passage 111c is directly or indirectly via a control valve, solenoid valve, piston, or the like (not shown), the primary hydraulic chamber 23a, the secondary hydraulic chamber 23b, the low brake 32, the high clutch 33, and the reverse brake. 34 is connected.

  The torque converter regulator valve 112a is a valve that regulates the torque converter pressure PT / C from the oil discharged when regulating the line pressure PL obtained through the torque converter oil passage 112d. A spring (not shown) or the like acts on one end side of the torque converter regulator valve 112a, and a feedback pressure acts on the other end side. The torque converter regulator valve 112a discharges the oil discharged when adjusting the torque converter pressure PT / C to the lubricating oil passage 112e. The discharged oil is used for a lubricating LUB such as a power train through a lubricating oil passage 112e. Further, the lubricating oil passage 112e connected to the torque converter regulator valve 112a is connected to the lockup control valve 112b.

  The lockup control valve 112b uses the torque converter pressure PT / C supplied via the torque converter oil passage 112d as a source pressure, and uses the solenoid force generated by the lockup solenoid 112c as an operation signal pressure, This valve creates a differential pressure ΔP between Pa and the torque converter release pressure Pr. The lock-up control valve 112b is also connected to a lubricating oil path 112e different from the lubricating oil path 112e extending from the torque converter regulator valve 112a.

The lockup solenoid 112c uses the torque converter pressure PT / C supplied via the torque converter oil passage 112d as a source pressure, and the solenoid force based on the lockup instruction value PL / U ^* from the transmission controller 12 as the operation signal pressure. And a solenoid that generates an operation signal pressure to the lock-up control valve 112b. For example, when the lockup solenoid 112c is on, the lockup state is established, and when the lockup solenoid 112c is off, the unlockup state is established.

In the lock-up state, the torque converter pressure PT / C is supplied to the supply pressure oil passage 112f, whereby the torque converter supply pressure Pa is gradually increased, and the torque converter release pressure Pr becomes the release pressure oil passage 112g and the lockup control valve. The oil is discharged to the lubricating oil passage 112e through 112b. As a result, the differential pressure between the torque converter supply pressure Pa and the torque converter release pressure Pr increases, and the lockup clutch 9 is engaged. That is, the engine 1 and the transmission 4 are directly connected.
In the unlocked state, the torque converter pressure PT / C is supplied to the release pressure oil passage 112g, whereby the torque converter release pressure Pr gradually increases and the lockup clutch 9 is released. The supplied torque converter pressure PT / C is discharged to the lubricating oil passage 112e via the supply pressure oil passage 112f and the lockup control valve 112b. As a result, the differential pressure between the torque converter supply pressure Pa and the torque converter release pressure Pr is reduced, and the lockup clutch 9 is released. That is, the engine 1 and the transmission 4 are connected by a fluid coupling.

[Coast stop control configuration]
In order to suppress the fuel consumption as much as possible, the engine controller 14 according to the first embodiment performs an engine operation while the vehicle is coasting (during coasting) in addition to “idle stop control” that stops the engine 1 while the vehicle is stopped. “Coast stop control” is performed to stop 1.

  The “coast stop control” is control for suppressing fuel consumption by automatically stopping the engine 1 while the vehicle is coasting in a low vehicle speed range. The “coast stop control” and the “fuel cut control” executed when the accelerator is off (accelerator release) are common in that the fuel supply to the engine 1 is stopped. However, the normal “fuel cut control” is executed at a relatively high speed, and the lock-up clutch 9 of the torque converter 2 is engaged to ensure engine braking. On the other hand, the “coast stop control” is executed during coasting at a relatively low speed immediately before the vehicle stops, and differs in that the lockup clutch 9 is released to stop the rotation of the engine 1.

In executing the “coast stop control”, the engine controller 14 determines, for example, the following conditions (a) to (e).
(a): The foot is released from the accelerator pedal (accelerator opening APO = 0)
(b): Brake pedal is depressed (brake sensor not shown is ON)
(c): Vehicle speed VSP is below a predetermined low vehicle speed (for example, 15 km / h)
(d): Lock-up clutch 9 is released (for example, vehicle speed is 13 km / h)
(e): The high speed mode (second speed) by the engagement of the high clutch 33 is selected. These conditions (a) to (e) are conditions for judging that the driver intends to stop in other words. is there.

  The engine controller 14 executes coast stop control for stopping the rotation of the engine 1 by stopping the supply of fuel to the engine 1 when all the start conditions (a) to (e) of the coast stop control are satisfied. Start. At the same time, a coast stop control in-progress flag CS / FLG representing the execution of coast stop control is set (CS / FLG = 1) and output to the integrated controller 13 and the transmission controller 12. During coast stop control, there is an accelerator depression operation or brake release operation.If condition (a) or (b) is not satisfied, coast stop control is terminated using this as an end condition, and the coast stop control flag Lower CS / FLG (CS / FLG = 0).

  When the coast stop control is started, the mechanical oil pump 10 that generates hydraulic pressure by the driving force of the engine 1 also stops gradually as the engine speed decreases, and the discharge pressure from the mechanical oil pump 10 is changed to the hydraulic control circuit 11. No longer supplied. On the other hand, even when the engine 1 is stopped, hydraulic pressure is originally required for the belt clamping force by the pulleys of the variator 20 and the engagement of the frictional engagement elements of the auxiliary transmission mechanism 30. For this purpose, for example, as described in JP-A-2013-204722, as an oil pump, in addition to an engine-driven mechanical oil pump, an electric oil pump that supplements hydraulic pressure while the engine is stopped is mounted. . On the other hand, in the first embodiment, the electric oil pump is abolished mainly for the purpose of reducing the system cost and only the mechanical oil pump 10 is installed. It becomes necessary to perform stop-compatible transmission control. In view of this, coast stop-compatible transmission control is performed on the transmission controller 12 side based on input information such as the coast stop control flag and the engine speed Ne.

  Since the start condition of the coast stop control includes the high speed mode selection condition (e) as described above, when the coast stop control is started, the engaged high clutch 33 is released. On the other hand, when the coast stop control is finished while the vehicle is stopped, the vehicle starts with the lowest gear ratio in the low-speed mode, so the low brake 32 is engaged as a starting clutch. Since the start condition of the coast stop control includes the high speed mode selection condition (e), the coast stop control is not started if the low brake 32 is engaged during traveling. When the vehicle stops in such a state, idle stop control is performed. In the idling stop control, since the control is started on the condition that the vehicle is stopped, the low brake 32 that is engaged by the selection of the low speed mode is released after the vehicle stops. When the idle stop control is completed, the low brake 32 is engaged as a starting clutch because the vehicle starts at the lowest speed ratio in the low speed mode, as is the case with the coast stop control.

[Coast stop-compatible transmission control configuration]
5 to 7 show the coast stop-compatible transmission control process executed by the transmission controller 12 of the first embodiment (transmission control means). Hereinafter, each step of FIGS. 5 to 7 showing the configuration of the coast stop-compatible transmission control processing will be described. The abbreviation for coast stop control is called “CS”, and the abbreviation for idle stop control is called “IS”.

In step S1, it is determined whether or not it is permitted to enter the coast stop control. If YES (CS entry is permitted), the process proceeds to step S2. If NO (CS entry is not permitted), the process proceeds to the end.
Here, the determination of permission to enter CS is made when the coast stop control flag is changed from flag = 0 (CS non-control) to flag = 1 (CS control is in progress). On the engine control side, when the coast stop control start condition is satisfied, the fuel injection is cut, the rotation speed of the engine 1 is reduced, and then the coast stop control to enter the engine stop state is started.

In step S2, following the determination that the CS entry is permitted in step S1 or the determination that the engine speed is greater than the predetermined value in step S3, it is determined whether or not there is a determination of a departure from the coast stop control. judge. If YES (CS missing determination is present), the process proceeds to step S9. If NO (CS missing determination is not present), the process proceeds to step S3.
Here, the determination that there is a CS loss determination is made when the coast stop control flag is switched from flag = 1 (CS control in progress) to flag = 0 (CS non-control). On the engine control side, when the coast stop control end condition is satisfied, if the engine speed Ne is equal to or higher than a predetermined speed (for example, 1000 rpm), the engine 1 is performed by fuel injection and ignition without using the starter motor 15. Is restarted (recovered). When the engine speed Ne is lower than a predetermined engine speed (for example, 1000 rpm) and recovery cannot be performed, the engine cranking is performed using the starter motor 15 after the engine speed Ne has sufficiently decreased, and fuel injection is resumed. A starter start for starting the engine 1 is performed.

In step S3, it is determined whether or not the engine speed Ne is equal to or less than a predetermined value (for example, 800 rpm) following the determination in step S2 that there is no CS missing determination. If YES (Ne ≦ predetermined value), the process proceeds to step S4. If NO (Ne> predetermined value), the process returns to step S2.
Here, the predetermined value (predetermined rotational speed) of the engine rotational speed Ne is the rotational speed that can be prepared for restart by intervention of the accelerator stepping operation while suppressing the occurrence of a shock (release shock) when the high clutch 33 is released. Set to The predetermined value (for example, 800 rpm) of the engine speed Ne is such that the engine 1 recovers at the last rotation speed (for example, 1000 rpm) at which recovery starts, and after the recovery returns, the engine speed Ne is under. Even if the engine is shot and falls below this rotational speed (1000 rpm), the rotational speed (800 rpm) prevents the high clutch 33 from being released even if the engine 1 recovers.

  In step S4, following the determination that Ne ≦ predetermined value in step S3, release of the engaged high clutch 33 (in the engaged state) is started, and the process proceeds to step S5.

  In step S5, following the determination that the high clutch has been released in step S4 or that the high clutch has not been completely released in step S6, whether or not there is a determination of exit from the coast stop control as in step S2. Determine. If YES (CS missing determination is present), the process proceeds to step S9. If NO (CS missing determination is not present), the process proceeds to step S6.

  In step S6, it is determined whether or not the complete release of the high clutch 33 has been completed following the determination in step S5 that there is no CS missing determination. If YES (high clutch complete release complete), the process proceeds to step S7. If NO (high clutch complete release incomplete), the process returns to step S5.

In step S7, following the determination that the high clutch complete release has been completed in step S6, CS / IS shift control is executed, and the process proceeds to step S8.
Here, in CS / IS shift control,
(a) Fixed target variator ratio
(b) Invalidation of target slew ratio change limit
(c) Secondary gear position 2nd gear → 1st gear
(d) Primary current command value = Control by CS / IS command current value is performed.

  In step S8, following the determination that there is no CS / IS shift control in step S7 or no CS omission determination in step S8, the omission determination from the coast stop control is performed as in steps S2 and S5. It is determined whether or not there is. If YES (CS missing determination is present), the process proceeds to step S9. If NO (CS missing determination is not present), the determination in step S8 is repeated.

In step S9, it is determined whether or not the starter engine is started following the determination that the CS missing determination is present in step S2, step S5, or step S8. If YES (starter engine start), the process proceeds to step S11. If NO (recovery return), the process proceeds to step S10.
Here, whether the starter engine starts or recovers is determined by the engine speed at the determination timing of the CS missing determination. For example, if the engine speed Ne is maintained at a predetermined speed (1000 rpm) or more when the CS missing is determined, recovery can be recovered by fuel injection and ignition, but the engine speed Ne is set to the predetermined speed (1000 rpm). ), The starter is started using the starter motor 15.

In step S10, following the determination that the recovery is in step S9, it is determined whether or not the high clutch 33 is being engaged. If YES (except when the clutch is engaged), the process proceeds to step S11. If NO (clutch is engaged), the process proceeds to step S26.
Here, the state other than the clutch being engaged means that the state of the high clutch 33 is completely engaged (the state in which the high clutch 33 is not slipping).

  In step S11, following the determination that the starter engine is started in step S9 or that the clutch is not engaged in step S10, the clutch hydraulic pressure instruction value to the released high clutch 33 is the clutch It is determined whether or not the hydraulic pressure instruction value = 0 MPa. If YES (clutch oil pressure instruction value = 0 MPa), the process proceeds to step S13, and if NO (clutch oil pressure instruction value ≠ 0 MPa), the process proceeds to step S12.

In step S12, following the determination in step S11 that the clutch hydraulic pressure instruction value ≠ 0 MPa, the clutch hydraulic pressure instruction value PH / C ^* for the released high clutch 33 is switched to the clutch hydraulic pressure instruction value = 0 MPa. Proceed to S13.

In step S13, following the determination that the clutch hydraulic pressure command value = 0 MPa in step S11 or the switching to the clutch hydraulic pressure command value = 0 MPa in step S12, the primary current command value PriSOL / I ^* is set to 1A ( 1 ampere), the clutch hydraulic pressure command value PL / B ^* is changed from 0 MPa to a stroke start pressure level command value, and the process proceeds to step S14.
Here, the primary current instruction value PriSOL / I ^* of 1A may close the hydraulic circuit to the primary hydraulic cylinder 23a against the spring biasing force of the primary solenoid in the absence of the base pressure supplied to the primary solenoid. This is the current indication value that can be generated.

In step S14, following the setting of the primary current instruction value PriSOL / I ^* and the change of the clutch hydraulic pressure instruction value PL / B ^* in step S13, the engine speed Ne is equal to or greater than a predetermined value (predetermined engine speed, for example, 500 rpm). It is determined whether or not. If YES (Ne ≧ 500 rpm), the process proceeds to step S15. If NO (Ne <500 rpm), the determination in step S14 is repeated.
Here, the predetermined value of the engine rotational speed Ne is set to a rotational speed at which the engine-driven mechanical oil pump 10 can generate a line pressure PL that can be hydraulically controlled to engage the low brake 32.

  In step S15, following the determination that Ne ≧ 500 rpm in step S14 or the determination that the timer value <predetermined value in step S16, the actual line pressure PL detected by the line pressure sensor 44 is a predetermined value. It is determined whether or not the value (predetermined line pressure, for example, 0.5 MPa) or more. If YES (PL ≧ predetermined value), the process proceeds to step S17. If NO (PL <predetermined value), the process proceeds to step S16.

  In step S16 (timer counting means), following the determination that PL <predetermined value in step S15, the timer value that is started from the time when it is determined that Ne ≧ 500 rpm and is added as time passes is a predetermined value. It is determined whether or not (predetermined timer value) or more. If YES (timer value ≧ predetermined value), the process proceeds to step S161. If NO (timer value <predetermined value), the process returns to step S15.

In step S161 (line pressure failure diagnosis means), following the determination in step S16 that the timer value ≧ predetermined value, a lockup clutch 9 engagement command for the released lockup clutch 9 is issued as a lockup hydraulic control circuit. 112 (lockup solenoid 112c), and the process proceeds to step S162.
Here, the “line pressure system” includes the line pressure sensor 44 and the line pressure control circuit 111 including the mechanical oil pump 10.

In step S162 (line pressure system failure diagnosis means), following the output of the lockup clutch 9 engagement command in step S161 to the lockup hydraulic control circuit 112, the primary rotational speed Npri, which is the rotational speed of the drive system, is changed. Based on this, it is determined whether or not the lockup clutch 9 is operated. That is, it is determined whether or not the primary rotational speed Npri has increased. If YES (lockup clutch 9 operating state, primary rotational speed Npri has increased), the process proceeds to step S163, and if NO (lockup clutch 9 inactive state, primary rotational speed Npri does not increase), the process proceeds to the end. In step S163 (line pressure system failure diagnosis means), following the determination that the lockup clutch 9 has been operated in step S162, a release command for the lockup clutch 9 is output to the lockup hydraulic control circuit 112, and the process proceeds to step S17. .
Here, the “lock-up clutch 9 operating state” refers to a case where the line pressure control circuit 111 or the like has not failed and the line pressure sensor 44 has been diagnosed as having failed. That is, the hydraulic control of the continuously variable transmission with the auxiliary transmission is possible. On the contrary, the “lock-up clutch 9 inoperative state” is a case where the line pressure control circuit 111 is diagnosed as having a failure. That is, it is difficult to control the hydraulic pressure of the continuously variable transmission with the auxiliary transmission.

In step S17, following the determination that PL ≧ predetermined value in step S15 or that the lockup clutch 9 is operating in step S161, the primary current instruction value PriSOL / I ^* is output. 1A (1 ampere) is canceled, and the clutch hydraulic pressure command value PL / B ^* is changed from the stroke start pressure level command value to the hydraulic charge command value, and the process proceeds to step S18. By releasing the primary current instruction value PriSOL / I * of 1A (1 ampere), the primary hydraulic cylinder 23a of the primary pulley 21 is supplied with hydraulic pressure based on the target hydraulic pressure.

In Step S18, following the cancellation of the primary current instruction value PriSOL / I ^* and the change of the clutch oil pressure instruction value PL / B ^* in Step S17, whether or not the hydraulic charging to the low brake 32 that is engaged at the time of restart is completed. Determine whether. If YES (hydraulic filling is complete), the process proceeds to step S19. If NO (hydraulic filling is not complete), the determination in step S18 is repeated.

  In step S19, following the determination that the hydraulic pressure filling is completed in step S18, the fixed ratio of the target variator ratio fixed in step S7 is cleared, and the process proceeds to step S20.

In step S20, following the target variator ratio fixed clear in step S19, the clutch hydraulic pressure command value upper limit regulation value PL / B ^* max for the low brake 32 is calculated based on the actual line pressure PL detected by the line pressure sensor 44. Then, the process proceeds to step S21.
Here, the clutch hydraulic pressure command value upper limit regulation value PL / B ^* max calculates the belt capacity T of the variator 20 based on the actual line pressure PL, and calculates a predetermined margin α from the belt capacity calculated value T (PL). deducted,
PL / B ^* max = T (PL) -α
It is calculated by the following formula.

In step S21, following the calculation of the clutch hydraulic pressure command value upper limit regulation value PL / B ^* max in step S20, engagement of the low brake 32, which is the starting clutch, with a clutch engagement command hydraulic pressure described later is started, and the process proceeds to step S22.

In step S22, following the determination that clutch engagement is started in step S21 or clutch engagement is not completed in step S25, the clutch hydraulic pressure instruction value PL / B ^* to the low brake 32 that is the starting clutch is It is determined whether or not the hydraulic pressure instruction value upper limit regulation value PL / B ^* max is less. If YES (clutch oil pressure instruction value <clutch oil pressure instruction value upper limit restriction value), the process proceeds to step S23. If NO (clutch oil pressure instruction value ≧ clutch oil pressure instruction value upper limit restriction value), the process proceeds to step S24.

In step S23, following the determination that the clutch hydraulic pressure command value <the clutch hydraulic pressure command value upper limit regulation value in step S22, the clutch hydraulic pressure command value PL / B ^* is set as the clutch engagement command hydraulic pressure, and the process proceeds to step S25.
Here, the clutch engagement instruction hydraulic pressure is
Clutch engagement command oil pressure = τNe2 x t x gear ratio + (torque required for rotation reduction)
It is calculated by the following formula.
“Τ” is a torque capacity coefficient, “t” is a torque ratio, and “τNe2 × t” represents turbine torque. “Gear ratio” is a reduction gear ratio, and “torque required for rotation reduction” corresponds to an inertia torque of the variator 20.

In step S24, following the determination in step S22 that the clutch hydraulic pressure command value ≧ the clutch hydraulic pressure command value upper limit regulation value, the clutch hydraulic pressure command value PL / B ^{* is changed} to the clutch hydraulic pressure command value upper limit regulation value PL / B ^* max. And go to step S25.

In step S25, following the setting of the clutch hydraulic pressure instruction value PL / B ^* in step S23 or step S24, it is determined whether or not the engagement of the low brake 32, which is the starting clutch, has been completed. If YES (clutch engagement is complete), the process proceeds to step S26. If NO (clutch engagement is not complete), the process returns to step S22.

In step S26, following the determination that the clutch engagement is complete in step S25 or the clutch engagement being performed in step S10, the clutch hydraulic pressure instruction value PL / B ^* is set as the clutch engagement maintenance instruction hydraulic pressure. Go to the end.

Next, the operation will be described.
The operation of the control device for the continuously variable transmission with the auxiliary transmission according to the first embodiment will be described by dividing it into “overall operation of transmission control corresponding to coast stop” and “line pressure system failure diagnosis operation”.

[Overall action of coast stop gearbox control]
FIG. 8 shows a time chart based on coast stop compatible transmission control. Hereinafter, the overall operation of the coast stop-compatible transmission control will be described with reference to FIGS.

  After the coast stop control condition is satisfied, when the vehicle shifts from coast stop control to idle stop without CS disconnection before the vehicle stop by intervention such as an accelerator operation, and then the vehicle starts, FIGS. In the flowchart shown in FIG.

  When it is permitted to enter the coast stop control and there is no determination of the exit from the coast stop control, in the flowchart of FIG. 5, the process proceeds from step S1 to step S2 to step S3, and in step S3, the engine speed Ne. While the value exceeds the predetermined value, the flow from step S2 to step S3 is repeated. When it is determined in step S3 that the engine speed Ne has become equal to or less than the predetermined value, the process proceeds from step S3 to step S4, and in step S4, the fast clutch 33 that has been engaged is released. If there is no disconnection determination from the coast stop control during the release of the high clutch 33, the process proceeds from step S4 to step S5 to step S6, and from step S5 to step S6 until the high clutch 33 completes the complete release. The forward flow is repeated.

If it is determined in step S6 that the complete release of the high clutch 33 has been completed, the process proceeds to step S7. In step S7,
(a) Fixed target variator ratio
(b) Invalidation of target slew ratio change limit
(c) Secondary gear position 2nd gear → 1st gear
(d) Primary current command value = CS / IS shift control by the command current value during CS / IS is executed. This CS / IS shift control is continuously executed until it is determined in step S8 that there is a CS missing determination.

If it is determined in step S8 that there is a CS missing determination in a situation where the engine is stopped due to engine stop, that is, a starter start is performed instead of recovery, the process proceeds from step S9 to step S11 to step S13. In step S13, the primary current command value PriSOL / I ^* is set to 1A (1 ampere), and the clutch hydraulic pressure command value PL / B ^* is changed from 0 MPa to a stroke start pressure level command value. In the next step S14, it is determined whether or not the engine speed Ne is a predetermined value or more. When the engine speed Ne becomes equal to or greater than a predetermined value due to starter start, the process proceeds from step S14 to step S15 → step S17, or from step S14 to step S15 → step S16 → step S161 → step S162 → step S17. In step S17, 1A (1 ampere) output as the primary current command value PriSOL / I ^* is released, and the clutch hydraulic pressure command value PL / B ^* is changed from the stroke start pressure level command value to the hydraulic charge command value. Be changed. In the next step S18, it is determined whether or not the hydraulic charging to the low brake 32 that is engaged at the time of restart is completed. When the hydraulic charging to the low brake 32 is completed, the process proceeds to step S19. In S7, the fixed target variator ratio is cleared.

When the filling of the hydraulic pressure to the low brake 32 is completed and the fixation of the target variator ratio is cleared, the process proceeds to step S20. In step S20, the low brake 32 is returned to based on the actual line pressure PL detected by the line pressure sensor 44. The clutch hydraulic pressure command value upper limit regulation value PL / B ^* max is calculated. In the next step S21, engagement of the low brake 32, which is a starting clutch, is started. After the engagement of the low brake 32 is started, while the clutch hydraulic pressure command value is smaller than the clutch hydraulic pressure command value upper limit regulation value, the flow of steps S22 → step S23 → step S25 is repeated, and in step S23, the clutch hydraulic pressure command value PL / B ^* is the clutch engagement instruction hydraulic pressure. On the other hand, if the clutch hydraulic pressure command value ≧ the clutch hydraulic pressure command value upper limit regulation value after the low brake 32 starts to be engaged, the flow from step S22 → step S24 → step S25 is repeated. In step S24, the clutch hydraulic pressure command value PL / B ^* is the clutch hydraulic pressure command value upper limit regulation value PL / B ^* max. Then, when it is determined in step S25 that the engagement of the low brake 32, which is the starting clutch, has been completed, the process proceeds from step S25 to step S26, and in step S26, the clutch hydraulic pressure instruction value PL / B ^* is maintained as clutch engagement maintained. The command hydraulic pressure is set, and the process proceeds to the end to finish the coast stop-compatible transmission control.

  In the time chart shown in FIG. 8, time t0 is a CS entry permission determination time, time t1 is a high clutch release start time, time t2 is a clutch complete release completion time, time t3 is a vehicle stop time, time t4 is a CS loss determination time, Time t5 is a stroke start pressure instruction end time, and time t6 is a filling hydraulic pressure instruction end time. Time T1 is a clutch release time, time T2 is a clutch release maintenance time, time T3 is a clutch original pressure rising waiting time, time T4 is a clutch hydraulic pressure filling time, and time T5 is a clutch engagement time.

  In other words, when the CS entry permission determination is made at time t0, the decrease in the engine speed Ne is monitored, and as shown in the characteristics of the high clutch hydraulic pressure PH / C, the time t1 when the engine speed Ne becomes a predetermined value or less. The release of the high clutch 33 is started from (point D). At time t2, complete release of the high clutch 33 is completed. Thus, the time from time t1 to time t2 is the clutch release time T1.

When the clutch complete release completion time t2 is reached, the vehicle stop time t3 elapses and the CS release determination time t4 is set as the clutch release maintaining time T2, and the CS / IS shift control is executed. When CS / IS shift control is executed, the sub-shift gear position is switched from 2nd gear to 1st gear, and during the clutch release maintenance time T2, the primary current command value PriSOL / I ^* is the IS / CS hydraulic pressure command value. (= 0A). In addition, the target variator ratio is fixed, and the target slew ratio change amount restriction is invalidated to maintain the lowest gear ratio. The lowest speed ratio maintaining time T6 is a time obtained by adding the clutch original pressure rising waiting time T3 and the clutch hydraulic pressure charging time T4 to the clutch disengagement maintaining time T2.

When the CS omission determination time t4 is reached, the starter start of the engine 1 is started, so that the engine speed Ne starts to increase at a time t4 ′ slightly delayed from the time t4. The line pressure PL rises based on the discharge pressure from the oil pump 10. Then, from the CS missing determination time t4 to the stroke start pressure command end time t5, the clutch original pressure rise waiting time T3 is set, and the clutch hydraulic pressure command value PL / B ^* is set to the stroke start pressure level command value, and the primary current command value PriSOL / I ^* is the current skip instruction value (1A).

At the stroke start pressure instruction end time t5, the engine speed Ne further increases, and the line pressure PL also rises to the target pressure. Then, from the stroke start pressure instruction end time t5 to the filling oil pressure instruction end time t6 is set as the clutch oil pressure filling time T4, the clutch oil pressure instruction value PL / B ^* is set as the oil pressure filling instruction value, and the primary current instruction value PriSOL / I ^* However, it is diagonally lowered from the current skip command value (1A) to the command value for obtaining the target primary pressure.

At the filling hydraulic pressure command end time t6, the low brake 32 actually starts to be engaged, and the clutch hydraulic pressure command value upper limit regulation value PL / B ^* max is calculated from the actual line pressure PL, and the clutch hydraulic pressure command value upper limit regulation value PL / B ^* Outputs the clutch hydraulic pressure indication value PL / B ^* that does not exceed max. Thereby, after the filling hydraulic pressure instruction end time t6, the engagement of the low brake 32 proceeds, the transmission torque capacity TL / B of the low brake 32 increases, and the vehicle speed VSP also rises accordingly. In other words, the vehicle starts to restart almost at the timing when the filling hydraulic pressure instruction end time t6 is reached.

[Line pressure fault diagnosis]
If the line pressure sensor 44 cannot detect the line pressure PL when the vehicle is not running, a failure of the line pressure sensor 44 is suspected.
For example, each friction engagement element includes a solenoid valve connected to a line pressure source and a drain, and a hydraulic sensor that detects an actual oil pressure to each friction engagement element. A failure diagnosis device of a hydraulic pressure detection device that controls supply hydraulic pressure to a target hydraulic pressure and diagnoses a failure of a hydraulic pressure sensor based on a difference between the target hydraulic pressure and the actual hydraulic pressure is taken as a comparative example. According to the failure diagnosis device of the hydraulic pressure detection device of this comparative example, the failure diagnosis of the hydraulic pressure sensor detects the end of the engagement / release operation of each friction engagement element by each first solenoid valve after the key switch is turned on. Permitted after completion of the initial fastening / release operation. Or, the failure diagnosis of the hydraulic sensor is permitted after the key switch is turned on, when a selection from the stop range to the travel range is detected, and the solenoid valve is operated to perform precharge for failure diagnosis. The

  However, if the failure diagnosis of the hydraulic pressure sensor is permitted as described above and the failure of the hydraulic pressure sensor is diagnosed based on the difference between the target hydraulic pressure and the actual hydraulic pressure, even if the solenoid valve fails and no hydraulic pressure is supplied, the hydraulic pressure sensor A faulty and erroneous diagnosis is made.

  As described above, when it is diagnosed that the hydraulic sensor is malfunctioning, there is a problem that it is unknown whether the solenoid valve is malfunctioning or the hydraulic sensor is malfunctioning.

  On the other hand, in the first embodiment, when the engine speed Ne is equal to or higher than a predetermined engine speed (for example, 500 rpm), the line pressure PL detected by the line pressure sensor 44 is less than the predetermined line pressure (for example, 0.5 MPa). In this case, an engagement command for the lockup clutch 9 is output to the lockup hydraulic pressure control circuit 112, and it is determined whether or not the lockup clutch 9 is activated.

With this configuration, when the line pressure PL is adjusted to be equal to or higher than the predetermined line pressure by the line pressure control circuit 111, even if the line pressure PL detected by the line pressure sensor 44 is less than the predetermined line pressure, the line pressure PL is locked. The oil pressure to the lockup clutch 9 can be controlled by the up oil pressure control circuit 112. At this time, when the lock-up clutch 9 engagement command is output to the lock-up hydraulic control circuit 112 and it is determined that the lock-up clutch 9 is activated, the line pressure control circuit 111 is not broken and the line pressure sensor 44 is not broken. Diagnosed as faulty.
When the line pressure sensor 44 is normal and the line pressure control circuit 111 has not adjusted the line pressure PL to a predetermined line pressure or higher, the lockup hydraulic control circuit 112 controls the hydraulic pressure to the lockup clutch 9. I can't control it. At this time, even if the engagement command for the lockup clutch 9 is output to the lockup hydraulic control circuit 112, it is determined that the lockup clutch 9 is inoperative. If determined in this way, it is diagnosed that the line pressure control circuit 111 has failed.

Therefore, when the hydraulic control of the continuously variable transmission with the auxiliary transmission is possible, the diagnosis of the failure of the line pressure sensor 44 and the failure of the line pressure control circuit 111 is made by determining whether the lockup clutch 9 is activated or not. Can do.
When it is determined that the lock-up clutch 9 has been operated, it is determined that the lock-up clutch 9 is operating from the release to the fastening side, that is, it is determined that torque is being transmitted by the lock-up clutch 9. I hope you can. For this reason, not only the lockup state (engaged) of the lockup clutch 9 in which the engine 1 and the continuously variable transmission with the auxiliary transmission are directly connected, but also the slip lockup state (slip engagement) of the lockup clutch 9 is included.

  In the first embodiment, the increase in the engine speed Ne after the engine is started is monitored, and when the engine speed Ne is equal to or higher than a predetermined engine speed (for example, 500 rpm), the line pressure PL detected by the line pressure sensor 44 is When the pressure is less than a predetermined line pressure (for example, 0.5 MPa) and the timer value becomes equal to or greater than the predetermined timer value, the engagement command for the lockup clutch 9 is output to the lockup hydraulic pressure control circuit 112.

  With this configuration, the failure of the line pressure system is diagnosed after the elapse of a predetermined timer value that takes into account the delay in regulating the line pressure PL, the response delay of the line pressure sensor 44, and the like. For this reason, it can be prevented that a line pressure system that has not failed is diagnosed as being broken.

  Therefore, when starting the engine, the line pressure sensor 44 failure and the line pressure control circuit 111 failure can be diagnosed with high accuracy.

  In the first embodiment, when engine stop control (coast stop control / idle stop control) is performed, an increase in the engine speed Ne after engine restart is monitored.

  With this configuration, when the engine of the vehicle on which the engine stop control is mounted is restarted, it is possible to diagnose and diagnose the failure of the line pressure sensor 44 and the failure of the line pressure control circuit 111 (FIG. 6, step S14 → step S15 → step S16). → Step S161 → Step S162 → Step S163 → Step S17 or Step S14 → Step S15 → Step S16 → Step S161 → Step S162 → End).

  In the first embodiment, it is determined whether or not the lockup clutch 9 is operated based on a change in the primary rotational speed Npri detected by the rotational speed sensor 42.

  With this configuration, after the lock-up clutch 9 engagement command is output to the lock-up hydraulic pressure control circuit 112, the lock-up clutch 9 depends on whether the detected change in the primary rotation speed Npri, that is, whether the primary rotation speed Npri has increased. Can be determined. That is, when the primary rotational speed Npri increases, it is determined that the lockup clutch 9 has been operated, and when the primary rotational speed Npri does not increase (does not change), it is determined that the lockup clutch 9 is inactive.

  Therefore, when the oil pressure control of the continuously variable transmission with the sub-transmission is possible using the rotation speed sensor 42 which is the existing configuration of the continuously variable transmission with the sub-transmission, the lock-up clutch 9 is activated or deactivated. The state can be reliably determined.

Next, the effect will be described.
In the control device for the continuously variable transmission with the auxiliary transmission according to the first embodiment, the following effects can be obtained.

(1) Engine 1 and
A transmission (a continuously variable transmission with a sub-transmission) interposed between the engine 1 and the drive wheel 7;
A torque converter 2 having a lock-up clutch 9 interposed between the engine 1 and the transmission (a continuously variable transmission with a sub-transmission);
A mechanical oil pump 10 driven by the engine 1;
A line pressure control circuit 111 provided in an oil passage (line pressure oil passage 111c) from the mechanical oil pump 10 to regulate the line pressure PL;
A lockup hydraulic pressure control circuit 112 provided at a downstream position of the line pressure control circuit 111 for controlling the hydraulic pressure to the lockup clutch 9;
A line pressure sensor 44 for detecting the line pressure PL;
The line pressure PL detected by the line pressure sensor 44 when the engine speed Ne of the engine 1 is equal to or higher than a predetermined engine speed at which hydraulic control of the transmission (continuously variable transmission with auxiliary transmission) is possible. Is less than a predetermined line pressure, an engagement command for the lockup clutch 9 is output to the lockup hydraulic pressure control circuit 112 to determine whether or not the lockup clutch 9 has been operated. A transmission controller 12);
Is provided.
For this reason, when the hydraulic control of the continuously variable transmission with the auxiliary transmission is possible, the line pressure sensor 44 failure and the line pressure control circuit 111 failure are diagnosed by determining whether the lockup clutch 9 is operating or not. be able to.

(2) Timer count means (shifting) that monitors the increase in the engine speed Ne after the engine is started, starts when the engine speed Ne is equal to or higher than the predetermined engine speed, and adds a timer value over time. Machine controller 12),
The line pressure system failure diagnosis means (transmission controller 12) monitors an increase in the engine speed Ne after the engine is started, and when the engine speed Ne is equal to or higher than the predetermined engine speed, the line pressure When the line pressure PL detected by the sensor 44 is less than the predetermined line pressure and the timer value is equal to or greater than the predetermined timer value, an engagement command for the lockup clutch 9 is output to the lockup hydraulic pressure control circuit 112. .
For this reason, in addition to the effect of (1), the line pressure sensor 44 failure and the line pressure control circuit 111 failure can be diagnosed with high accuracy when the engine is started.

(3) An engine stop control means for stopping the engine when a predetermined start condition is satisfied, and ending the engine stop control (coast stop control / idle stop control) when the predetermined end condition is satisfied, and restarting the engine ( An engine controller 14),
When the engine stop control (coast stop control / idle stop control) is performed, the line pressure system failure diagnosis means (transmission controller 12) monitors the increase in the engine speed Ne after the engine is restarted.
For this reason, in addition to the effect of (2), when the engine is restarted in a vehicle equipped with engine stop control (coast stop control / idle stop control), the line pressure sensor 44 failure and the line pressure control circuit 111 failure are diagnosed separately. (FIG. 6, step S14 → step S15 → step S16 → step S161 → step S162 → step S163 → step S17 or step S14 → step S15 → step S16 → step S161 → step S162 → end).

  (4) a transmission rotational speed sensor (rotational speed sensor 42) for detecting a rotational speed (primary rotational speed Npri) of a rotational element of the transmission (continuously variable transmission with a sub-transmission);

The line pressure system failure diagnosing means (transmission controller 12) is a rotational speed of a rotational element of the transmission (continuous transmission with sub-transmission) detected by the transmission rotational speed sensor (rotational speed sensor 42). Based on the change in (primary rotational speed Npri), it is determined whether or not the lock-up clutch 9 is operated.
For this reason, in addition to the effects (1) to (3), the hydraulic control of the continuously variable transmission with the sub-transmission can be performed using the rotation speed sensor 42 which is the existing configuration of the continuously variable transmission with the sub-transmission. When possible, it is possible to reliably determine whether the lock-up clutch 9 is operating or not.

  As mentioned above, although the control apparatus of the continuously variable transmission of this invention was demonstrated based on Example 1, it is not restricted to this Example 1 about a concrete structure, Each claim of a claim is a claim. Design changes and additions are allowed without departing from the gist of the invention.

In the first embodiment, an example in which the rotation speed of the drive system is the primary rotation speed Npri (the rotation speed of the rotating element of the continuously variable transmission with a sub-transmission) is shown. However, the rotational speed of the drive system may be an example of input / output rotation of the torque converter or an example of engine speed. In short, it is sufficient if it can be determined that the torque is transmitted to the continuously variable transmission with the auxiliary transmission by the lock-up clutch 9.
Moreover, what can determine directly the action | operation or non-operation state of the lockup clutch 9 as rotation speed of a drive system may be used. For example, a hydraulic pressure sensor for detecting the hydraulic pressure in the torque converter 2 or a stroke sensor for detecting the stroke of the lock-up clutch 9 is provided, and the lock-up clutch is operated based on a change in information from at least one of the sensors. It may be determined whether or not. However, if the time during which no oil is supplied to the torque converter 2 continues due to idle stop control or the like, the oil in the torque converter 2 falls off (is discharged), and only with the oil newly supplied into the torque converter 2 Torque may not be transmitted. In such a case, even if the line pressure PL is regulated to a predetermined line pressure or higher by the line pressure control circuit 111, the lockup hydraulic control circuit 112 may not be able to control the hydraulic pressure to the lockup clutch 9. . For this reason, when using a hydraulic pressure sensor for detecting the hydraulic pressure in the torque converter 2 to determine whether or not the lockup clutch 9 has been operated, it is necessary to consider the above case.
If oil remains in the torque converter 2, the torque converter 2 may function as a fluid coupling and transmit torque even when the lockup clutch 9 remains in the non-engaged state. Even in such a case, the lockup clutch is based on the change (for example, change amount or change speed) of the rotation speed (primary rotation speed Npri) of the rotating element of the transmission (continuously variable transmission with sub-transmission). In order to determine that 9 has shifted from the non-engaged state to the engaged state, it can be determined whether or not the lockup clutch 9 has been actuated.

  In the first embodiment, an example in which the high clutch 33 included in the auxiliary transmission mechanism 30 is used as the clutch is shown. However, the clutch may be an example in which a clutch provided outside the continuously variable transmission with the auxiliary transmission is used. In short, it may be a clutch provided in a drive system in which a transmission is installed.

  In the first embodiment, the variator 20 is provided with a belt type continuously variable transmission mechanism. However, the variator 20 may be a continuously variable transmission mechanism in which a chain is wound around the pulleys 21 and 22 instead of the V belt 23. Alternatively, the variator 20 may be a toroidal continuously variable transmission mechanism in which a tiltable power roller is disposed between the input disk and the output disk.

  In the first embodiment, as the auxiliary transmission mechanism 30, a transmission mechanism having two speeds of first speed and second speed as the forward speed is shown. However, the sub-transmission mechanism 30 may be a transmission mechanism having three or more shift stages as forward shift stages.

  In the first embodiment, the sub-transmission mechanism 30 is configured using a Ravigneaux type planetary gear mechanism. However, the sub-transmission mechanism 30 may be configured by combining a normal planetary gear mechanism and a frictional engagement element, or a plurality of power transmission paths configured by a plurality of gear trains having different gear ratios. You may comprise by the frictional engagement element which switches a power transmission path | route.

  In the first embodiment, the actuator provided with the hydraulic cylinders 23a and 23b is shown as the actuator for displacing the movable conical plates of the pulleys 21 and 22 of the variator 20 in the axial direction. However, the actuator of the variator is not limited to that driven by hydraulic pressure but may be one that is electrically driven.

  In the first embodiment, an example in which a continuously variable transmission with a sub-transmission is used as the transmission is shown. However, the transmission may be an example using a continuously variable transmission without an auxiliary transmission, or an example using a stepped automatic transmission having a plurality of shift stages without using a continuously variable transmission. May be.

  In the first embodiment, the control device of the present invention is applied to an engine vehicle equipped with a continuously variable transmission with a sub-transmission. However, the control device for a vehicle transmission of the present invention can also be applied to a hybrid vehicle. In controlling the drive torque, any vehicle having a drive source (for example, an engine) that requires a minimum rotation speed (idle rotation speed) can be applied.

1 Engine 2 Torque converter 4 Transmission (continuously variable transmission with auxiliary transmission)
7 Drive wheel 9 Lock-up clutch 10 Mechanical oil pump 11 Hydraulic control circuit 111 Line pressure control circuit 111c Line pressure oil path 112 Lock-up hydraulic control circuit 12 Transmission controller (transmission control means, timer count means, line pressure system failure diagnosis means)
14 Engine controller (engine stop control means)
42 Speed sensor (Transmission speed sensor)
46 Engine speed sensor
Ne engine speed
Npri primary rotational speed (rotational speed of rotating element of continuously variable transmission with auxiliary transmission)

Claims (4)

Engine,
A transmission interposed between the engine and drive wheels;
A torque converter having a lock-up clutch interposed between the engine and the transmission;
A mechanical oil pump driven by the engine;
A line pressure control circuit that is provided in an oil passage from the mechanical oil pump and regulates the line pressure;
A lockup hydraulic pressure control circuit that is provided at a downstream position of the line pressure control circuit and controls the hydraulic pressure to the lockup clutch;
A line pressure sensor for detecting the line pressure;
When the engine speed of the engine is equal to or higher than a predetermined engine speed at which the hydraulic pressure of the transmission can be controlled, and the line pressure detected by the line pressure sensor is less than a predetermined line pressure, the lockup clutch A line pressure system failure diagnosis means for outputting an engagement command to the lockup hydraulic control circuit and determining whether or not the lockup clutch is operated;
A control device for a vehicle transmission, comprising: In the control apparatus for a vehicle transmission according to claim 1,
Monitoring a rise in the engine speed after engine startup, starting from a time when the engine speed is equal to or higher than the predetermined engine speed, and having a timer count means for adding a timer value over time;
The line pressure system failure diagnosing means monitors an increase in the engine speed after starting the engine, and when the engine speed is equal to or higher than the predetermined engine speed, the line pressure detected by the line pressure sensor is A control device for a vehicle transmission, wherein when the timer value is less than the predetermined line pressure and the timer value is equal to or greater than a predetermined timer value, an engagement command for the lockup clutch is output to the lockup hydraulic pressure control circuit. . In the control apparatus for a vehicle transmission according to claim 2,
Engine stop control means for stopping the engine when a predetermined start condition is satisfied, ending engine stop control when a predetermined end condition is satisfied, and restarting the engine;
The line pressure system failure diagnosis means monitors an increase in the engine speed after engine restart when the engine stop control is performed. In the control apparatus for a vehicle transmission according to any one of claims 1 to 3,
A transmission rotational speed sensor for detecting a rotational speed of a rotational element of the transmission;
The line pressure system failure diagnosing means determines whether or not the lock-up clutch has been operated based on a change in rotational speed of a rotational element of the transmission detected by the transmission rotational speed sensor. Control device for vehicle transmission.