WO2015146601A1 - Continuously variable transmission controller - Google Patents

Abstract

A continuously variable transmission controller which has first and second shift modes as torque transmission paths for transmitting torque from a drive source to an output shaft, and a direct connection mode which bypasses a torque transmission member of the continuously variable transmission mechanism, said continuously variable transmission controller being provided with first and second solenoid valves that operate torque transmission path switching mechanisms, wherein, if abnormalities in the switching mechanisms and/or the first and second solenoid valves are detected (YES in Step S16 or S20) when it is determined that the torque transmission path is to be switched (YES in Step S10), the continuously variable transmission is switched to the direct connection mode (Step S18, S24).

Description

Control device for continuously variable transmission

The present invention relates to a control device for a continuously variable transmission, and more specifically to a control device that performs a shift with a path change in a continuously variable transmission having a plurality of torque transmission paths.

Conventionally, in a continuously variable transmission having a continuously variable transmission mechanism, a stepped transmission mechanism including a gear mechanism is inserted between input and output shafts, and a plurality of torque transmission paths for transmitting a driving force of a driving source are provided. Thus, a continuously variable transmission is known in which the overall transmission ratio (total reduction ratio) of the continuously variable transmission is increased (for example, Patent Document 1).

In the technique described in Patent Document 1, a low-high control valve operated by a solenoid valve is provided, and the torque transmission path is switched between a low mode and a high mode by controlling the low-high control valve.

Japanese Patent No. 3,405,028

By the way, as described in Patent Document 1, it is well known to use a solenoid valve for switching the speed change mechanism. However, in Patent Document 1, no consideration is given to a technique when an abnormality occurs in the solenoid valve. There is no room for improvement in this regard.

That is, if an abnormality occurs in the solenoid valve, it is difficult to appropriately control the switching mechanism and the continuously variable transmission mechanism, and therefore a large load is applied to the torque transmission member (for example, a belt) of the switching mechanism and the continuously variable transmission mechanism. There is a risk of impairing its durability. Even if there is no abnormality in the solenoid valve, the same inconvenience as described above can occur even if an abnormality such as sticking occurs in the switching mechanism itself. However, Patent Document 1 does not provide any technique for solving such a problem. Absent.

Accordingly, an object of the present invention is to solve the above-described problem, and in a continuously variable transmission having a plurality of torque transmission paths, an abnormality occurs in a solenoid valve that operates the torque transmission path switching mechanism or the switching mechanism itself. Another object of the present invention is to provide a control device for a continuously variable transmission that improves the durability of a torque transmission member of a switching mechanism or a continuously variable transmission mechanism.

In order to solve the above-described problem, in claim 1, an input shaft connected to a drive source mounted on a vehicle, a first pulley, a second pulley, and between the first pulley and the second pulley. A driving force of the driving source that is inserted between the input shaft and an output shaft connected to driving wheels of the vehicle and is input from the input shaft. A continuously variable transmission mechanism for continuously changing the speed, a low-speed input path for inputting the driving force of the driving source input from the input shaft to the first pulley, and the driving source input from the input shaft. Input path switching for selectively switching between the high speed input path for inputting driving force to the second pulley and the input path through which the driving force input from the input shaft is to be transmitted among the low speed stage and the high speed stage input path Mechanism and the input path switching mechanism A first solenoid valve, a first output path connected to the second pulley and outputting the driving force transmitted to the output shaft via the low-speed stage input path and the endless flexible member; A second output path that is connected to the first pulley and outputs the driving force transmitted to the output shaft via the high-speed stage input path and the endless flexible member; and the first and second An output path switching mechanism that selectively switches an output path to which the driving force transmitted through the endless flexible member among the output paths is to be output to the output shaft, and a second that operates the output path switching mechanism. The target speed ratio of the continuously variable transmission is calculated according to the solenoid valve and the traveling state of the vehicle, and the input path switching mechanism and the output path switching mechanism are reduced based on the calculated target speed ratio. A continuously variable transmission comprising: a switching determination means for determining whether or not to switch at least one; and a control means for controlling the operation of the first and second solenoid valves based on the determination by the switching determination means. In the control device, the continuously variable transmission is configured to transmit a driving force of the driving source to the output shaft through the low-speed stage input path, an endless flexible member, and a first output path, There is a second speed change mode that transmits to the output shaft via a high-speed input path, an endless flexible member, and a second output path, and a direct connection mode that bypasses the endless flexible member and transmits to the output shaft. The control means includes an abnormality detection means for detecting an abnormality in at least one of the input path switching mechanism, the output path switching mechanism, and the first and second solenoid valves, and the switching determination means Therefore, when it is determined that at least one of the input path switching mechanism and the output path switching mechanism should be switched, the abnormality detection means causes the input path switching mechanism, the output path switching mechanism, and the first and second solenoid valves to be switched. When at least one of the abnormalities is detected, the continuously variable transmission is switched to the direct connection mode.

According to claim 2, the direct connection mode includes a first direct connection mode for transmitting a driving force of the driving source to the output shaft through at least the low speed stage input path and the second output path, and the high speed stage input. And a second direct coupling mode for transmitting the driving force of the driving source to the output shaft via the path and the first output path, and the control means includes the input path switching mechanism detected by the abnormality detection means and the The continuously variable transmission is configured to be switched to one of the first and second direct connection modes in response to an abnormality in the output path switching mechanism and the first and second solenoid valves.

According to a third aspect of the present invention, the control means is the input path detected by the abnormality detection means when the vehicle stops after the continuously variable transmission is switched to the second direct connection mode. When it is determined that the continuously variable transmission is in a predetermined state based on an abnormality in the switching mechanism, the output path switching mechanism, and the first and second solenoid valves, the continuously variable transmission is moved to the first speed change. The mode is switched to the mode and the first shift mode is maintained.

In claim 1, the low speed stage input path for inputting the driving force of the driving source to the first pulley of the continuously variable transmission mechanism, and the high speed stage for inputting the driving force of the driving source to the second pulley of the continuously variable transmission mechanism. An input path, an input path switching mechanism for switching these input paths, first and second output paths for outputting a driving force transmitted through an endless flexible member of the continuously variable transmission mechanism to the output shaft, and these outputs In a control device for a continuously variable transmission that includes an output route switching mechanism that switches a route and first and second solenoid valves that operate the input / output route switching mechanism, the continuously variable transmission uses the driving force of a drive source. A first speed change mode in which the low speed stage input path, the endless flexible member and the first output path are transmitted to the output shaft, the high speed stage input path, the endless flexible member and the second output path to the output shaft. The second transmission mode for transmission and the endless flexible member A direct connection mode for passing and transmitting to the output shaft, and the control means determines at least one of the input / output path switching mechanism and the first and second solenoid valves when switching the input / output path switching mechanism. When an abnormality is detected, the continuously variable transmission is configured to be switched to the direct connection mode. That is, when an abnormality (failure) of the switching mechanism itself or the solenoid valve that operates the switching mechanism is detected, the driving force (torque) of the driving source is not passed through the torque transmission member (for example, belt) of the continuously variable transmission mechanism. ) Can be transmitted, so even if a solenoid valve abnormality is detected, wear of the switching mechanism and belt can be effectively suppressed, so switching The durability of the mechanism and belt can be improved.

In particular, in a continuously variable transmission having a plurality of torque transmission paths (first and second transmission modes) via a continuously variable transmission mechanism, the abnormality of the solenoid valve is not only the operation (control) of the switching mechanism, It also makes it difficult to control the continuously variable transmission mechanism. However, in the invention according to claim 1, when abnormality of the switching mechanism or the solenoid valve is detected, the direct connection mode capable of transmitting the torque of the drive source to the output shaft without using the belt of the continuously variable transmission mechanism. Therefore, it is possible to effectively suppress wear of the switching mechanism and the belt, thereby improving the durability of the switching mechanism and the belt.

According to the second aspect, the direct connection mode includes a first direct connection mode and a second direct connection mode, and the control means sets the continuously variable transmission to either the first direct connection mode or the second direct connection mode according to the detected abnormality. It was configured to switch to. Therefore, in addition to the effects described above, it is possible to select the direct connection mode as appropriate according to the detected abnormality and quickly switch to the direct connection mode, thereby further improving the durability of the switching mechanism and the belt. It becomes possible.

In the third aspect, the vehicle is stopped after the continuously variable transmission is switched to the second direct connection mode, and the continuously variable transmission is brought into a predetermined state based on the abnormality detected by the abnormality detecting means. When it is determined that there is, the continuously variable transmission is switched to the first transmission mode and maintained. That is, when it is determined that the continuously variable transmission is in a predetermined state that can be switched to the first shift mode based on the detected abnormality, the continuously variable transmission is switched to the first shift mode. By configuring as above, it becomes possible to appropriately execute the shift control via the continuously variable transmission mechanism while further improving the durability of the switching mechanism and the belt, so that the vehicle start performance and fuel consumption are improved. It is also possible to prevent deterioration.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an overall control device for a continuously variable transmission according to an embodiment of the present invention. FIG. 2 is a hydraulic circuit diagram of a transmission hydraulic pressure supply mechanism of the apparatus shown in FIG. 1. It is a flowchart explaining operation | movement of the continuously variable transmission shown in FIG. It is explanatory drawing explaining the abnormal form of the continuously variable transmission shown in FIG. 3 is a state transition diagram for explaining torque transmission path switching control executed based on the processing of the flowchart of FIG.

Hereinafter, an embodiment for carrying out the continuously variable transmission control device according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing the overall control device of a continuously variable transmission according to a first embodiment of the present invention.

In FIG. 1, reference numeral 10 denotes an engine (internal combustion engine, drive source). The engine 10 is mounted on a vehicle 14 provided with drive wheels 12 (the vehicle 14 is partially indicated by the drive wheels 12 and the like).

The throttle valve 16 disposed in the intake system of the engine 10 is disconnected from the accelerator pedal 18 disposed on the floor surface of the vehicle driver's seat, and is a DBW (Drive By Wire) mechanism 20 including an actuator such as an electric motor. And is opened and closed by the DBW mechanism 20.

The intake air metered by the throttle valve 16 flows through an intake manifold (not shown) and mixes with fuel injected from an injector (not shown) in the vicinity of the intake port of each cylinder to form an air-fuel mixture. When an intake valve (not shown) is opened, it flows into a combustion chamber (not shown) of the cylinder. In the combustion chamber, the air-fuel mixture is ignited and combusted, and after driving the piston and rotating the crankshaft 22, the air-fuel mixture is discharged to the outside of the engine 10 as exhaust gas.

The rotation of the crankshaft 22 is input to a continuously variable transmission (Continuously Variable Transmission) T via a torque converter 24. That is, the crankshaft 22 is connected to the pump / impeller 24a of the torque converter 24, while the turbine runner 24b disposed opposite thereto and receiving fluid (hydraulic oil) is connected to the main input shaft (input shaft) 26. . The torque converter 24 includes a lockup clutch 24c.

The continuously variable transmission T includes a main input shaft 26 connected to the crankshaft 22 via a torque converter 24, and a first auxiliary input shaft 28 and a second auxiliary input shaft 30 arranged in parallel to the main input shaft 26. And a continuously variable transmission mechanism 32 disposed between the first sub input shaft 28 and the second sub input shaft 30.

The continuously variable transmission mechanism 32 is disposed on the first auxiliary input shaft 28, more precisely, the first pulley 32a disposed on the outer peripheral shaft, and the second auxiliary input shaft 30, more precisely on the outer peripheral shaft. The second pulley 32b and a power transmission element hung between the second pulley 32b, for example, a metal belt 32c.

The first pulley 32 a is relatively non-rotatable to the stationary pulley half 32 a 1 that is disposed so as not to be rotatable relative to the outer peripheral shaft of the first sub input shaft 28 and to be axially movable, and to the outer shaft of the first sub input shaft 28. The movable pulley half 32a2 that can move relative to the fixed pulley half 32a1 in the axial direction, and the movable pulley provided on the side of the movable pulley half 32a2 and supplied with hydraulic pressure (hydraulic oil pressure). A hydraulic actuator 32a3 including a piston, a cylinder, and a spring is provided to press the half body 32a2 toward the fixed pulley half body 32a1.

The second pulley 32b is not rotatable relative to the outer peripheral shaft of the second auxiliary input shaft 30 and the fixed pulley half 32b1 that is not rotatable relative to the outer peripheral shaft of the second auxiliary input shaft 30 and the outer peripheral shaft of the second auxiliary input shaft 30. The movable pulley half 32b2 that can move relative to the fixed pulley half 32b1 in the axial direction, and the movable pulley provided on the side of the movable pulley half 32b2 and supplied with hydraulic pressure (hydraulic oil pressure). A hydraulic actuator 32b3 composed of a piston, a cylinder, and a spring is provided to press the half 32b2 toward the fixed pulley half 32b1.

The main input shaft 26 is provided with an input path switching mechanism 34 including a LOW (deceleration) friction clutch 34a and a HIGH (acceleration) friction clutch 34b. A first reduction gear 36 is supported on the main input shaft 26 so as to be relatively rotatable, and a second reduction gear 38 that meshes with the first reduction gear 36 is fixed to the first sub input shaft 28. Therefore, when the LOW friction clutch 34 a is engaged, the torque of the engine 10 input from the main input shaft 26 is decelerated by the first and second reduction gears 36 and 38, and then is transmitted via the first auxiliary input shaft 28. It is input to one pulley 32a. In this specification, a path for transmitting torque from the main input shaft 26 to the first pulley 32a via the first and second reduction gears 36 and 38 and the first auxiliary input shaft 28 is referred to as a low speed input path. .

Further, a first speed increasing gear 40 is rotatably supported on the main input shaft 26, and a second speed increasing gear 42 meshing with the first speed increasing gear 40 is relatively rotated on the second sub input shaft 30. It is supported freely. Accordingly, when the HIGH friction clutch 34 b is engaged, the torque of the engine 10 input from the main input shaft 26 is increased by the first and second speed-up gears 40 and 42 and then passed through the second auxiliary input shaft 30. To the second pulley 32b. In this specification, a path for transmitting torque from the main input shaft 26 to the second pulley 32b via the first and second speed increasing gears 40 and 42 and the second auxiliary input shaft 30 is referred to as a high speed input path. .

The second auxiliary input shaft 30 is provided with a forward / reverse switching mechanism 44 made up of a dog clutch. That is, when a sleeve (not shown) of the forward / reverse switching mechanism 44 moves to the right side of the drawing, the second speed increasing gear 42 is engaged with the second auxiliary input shaft 30, and the rotation of the main input shaft 26 is reversed (reversed). As a result of the input to the second auxiliary input shaft 30, the vehicle 14 moves forward. On the other hand, when the sleeve of the forward / reverse switching mechanism 44 moves to the left side of the drawing, the reverse drive gear 44a is engaged with the second sub input shaft 30, and the rotation of the main input shaft 26 is reversed driven gear 44b, reverse idle gear 44c, reverse drive. As a result of being inverted by the gear 44 a and being input to the second auxiliary input shaft 30, the vehicle 14 moves backward.

A third reduction gear 48 that meshes with the first speed increasing gear 40 is supported on the intermediate output shaft 46 so as to be relatively rotatable, and a LOW side dog clutch 50 that couples the third reduction gear 48 to the intermediate output shaft 46 and its shift. A fork (LOW side shift fork, not shown) is provided. In this specification, the LOW side dog clutch 50 and the LOW side shift fork are collectively referred to as a LOW side meshing engagement mechanism.

A first final drive gear 52 is fixed to the intermediate output shaft 46, and the first final drive gear 52 meshes with a final driven gear 56 of the differential mechanism 54, and is directed from the differential mechanism 54 toward the left and right drive wheels 12. Connected to the extending output shaft 58.

In this specification, the second auxiliary input shaft 30, the forward / reverse switching mechanism 44, the first and second speed increasing gears 40 and 42, the third reduction gear 48, the intermediate output shaft 46, the first final drive gear 52, A path for transmitting torque from the second pulley 32b to the output shaft 58 via the final driven gear 56 and the differential mechanism 54 is referred to as a first output path.

A second final drive gear 60 is supported on the first auxiliary input shaft 28 in a relatively rotatable manner, and the HIGH side dog clutch 62 that couples the second final drive gear 60 to the first auxiliary input shaft 28 and its shift fork (HIGH). A side shift fork (not shown) is provided. In this specification, the above-described HIGH-side dog clutch 62 and HIGH-side shift fork are collectively referred to as a HIGH-side meshing engagement mechanism.

In this specification, a second route for transmitting torque from the first pulley 32a to the output shaft 58 via the first auxiliary input shaft 28, the second final drive gear 60, the final driven gear 56, and the differential mechanism 54 is referred to as a second route. Called the output path.

Also, the above-described LOW-side dog clutch 50 and LOW-side shift fork, and the HIGH-side dog clutch 62 and HIGH-side shift fork are collectively referred to as an output path switching mechanism.

The first, second, and third reduction gears 36, 38, and 48, the first and second speed-up gears 40 and 42, the first and second final drive gears 52 and 60, and the final driven gear 56 are generically named. This is called an auxiliary transmission mechanism.

Here, the gear ratio of each gear constituting the auxiliary transmission mechanism is set as follows. That is, the gear ratio of the high speed input path (first reduction gear 36 to the second reduction gear 38) is i _red , and the gear ratio of the low speed input path (first speed increase gear 40 to the second speed increase gear 42) is i. _ind is set so that i _red × i _min = i _ind , where i _min is the minimum speed ratio of the continuously variable transmission mechanism 32 from the first pulley 32a to the second pulley 32b. Further, the first output path (the second speed increasing gear 42 to the first speed increasing gear 40, the first speed increasing gear 40 to the third speed reducing gear 48 (first final drive gear 52), and the first final drive gear 52 to the final speed. If the gear ratio of the driven gear 56) is i _out1 and the gear ratio of the second output path (from the second final drive gear 60 to the final driven gear 56) is i _out2 , i _min × i _out1 = i _out2 is set. Is done.

Therefore, when the transmission ratio from the first pulley 32a to the second pulley 32b of the continuously variable transmission mechanism 32 is set to the minimum transmission ratio i _min , the transmission path constituted by the low speed input path and the first output path, More precisely, the transmission ratio of the torque transmission path (transmission path in the LOW mode described later) passing from the low speed stage input path to the first pulley 32a, the belt 32c, the second pulley 32b, and the first output path, and the high speed stage input path A transmission path constituted by the second output path, more precisely, a torque transmission path (in a HIGH mode to be described later) passing from the high speed stage input path to the second pulley 32b, the belt 32c, the first pulley 32a and the second output path. The transmission ratio of the torque transmission path is the same.

Here, the shift mode of the continuously variable transmission T having the above configuration will be described. In the LOW mode (first shift mode), the LOW friction clutch 34a and the LOW side dog clutch 50 of the input path switching mechanism 34 are engaged, while the HIGH friction clutch 34b and the HIGH side dog clutch 62 are released. Further, the forward / reverse switching mechanism 44 is switched to the forward side (the second speed increasing gear 42 is engaged).

Therefore, the torque transmission path of the engine 10 in the LOW mode is engine 10 → crankshaft 22 → torque converter 24 → main input shaft 26 → LOW friction clutch 34a → low speed stage input path (more specifically, the first reduction gear). 36 → second reduction gear 38 → first auxiliary input shaft 28) → first pulley 32a → belt 32c → second pulley 32b → first output path (more specifically, second auxiliary input shaft 30 → forward / reverse switching) Mechanism 44 → second speed increasing gear 42 → first speed increasing gear 40 → third speed reduction gear 48 → LOW side dog clutch 50 → intermediate output shaft 46 → first final drive gear 52 → final driven gear 56 → differential mechanism 54) → Output shaft 58 → drive wheel 12

In the direct connection LOW mode (direct connection mode; first direct connection mode) established during the transition (switching) from the LOW mode to the HIGH mode, the LOW friction clutch 34a and the HIGH side dog clutch 62 are engaged, while the HIGH friction is applied. The clutch 34b and the LOW side dog clutch 50 are released. Further, the side pressures of the first and second pulleys 32a and 32b are reduced so that torque from the engine 10 is not transmitted via the belt 32c.

Accordingly, the torque transmission path of the engine 10 in the direct connection LOW mode is as follows: engine 10 → crankshaft 22 → torque converter 24 → main input shaft 26 → LOW friction clutch 34a → first reduction gear 36 → second reduction gear 38 → first Sub input shaft 28 → HIGH side dog clutch 62 → second final drive gear 60 → final driven gear 56 → differential mechanism 54 → output shaft 58 → drive wheel 12. That is, in the direct connection LOW mode, the belt 32c of the continuously variable transmission mechanism 32 is bypassed, in other words, the torque of the engine 10 can be transmitted to the output shaft 58 (and the drive wheels 12) without passing through the belt 32c. it can.

Further, in the HIGH mode (second shift mode), the HIGH friction clutch 34b and the HIGH side dog clutch 62 of the input path switching mechanism 34 are engaged, while the LOW friction clutch 34a and the LOW side dog clutch 50 are released.

Therefore, the torque transmission path of the engine 10 in the HIGH mode is: engine 10 → crankshaft 22 → torque converter 24 → main input shaft 26 → HIGH friction clutch 34b → high speed input path (more specifically, the first speed increase Gear 40-> second speed increasing gear 42-> forward / reverse switching mechanism 44-> second auxiliary input shaft 30)-> second pulley 32b-> belt 32c-> first pulley 32a-> second output path (more specifically, first Sub-input shaft 28 → HIGH side dog clutch 62 → second final drive gear 60 → final driven gear 56 → differential mechanism 54) → output shaft 58 → drive wheel 12.

Thus, in the LOW mode and the HIGH mode, the torque transmission path in the continuously variable transmission mechanism 32 is configured to be reversed, whereby the overall transmission ratio in the entire continuously variable transmission T can be increased. .

In the direct connection HIGH mode (direct connection mode; second direct connection mode) established during the transition (switching) from the HIGH mode to the LOW mode, the HIGH friction clutch 34b and the LOW side dog clutch 50 are engaged, while the LOW friction is applied. The clutch 34a and the HIGH side dog clutch 62 are released. Further, as in the direct connection LOW mode, the side pressures of the first and second pulleys 32a and 32b are reduced so that torque from the engine 10 is not transmitted via the belt 32c.

Therefore, the torque transmission path of the engine 10 in the direct connection HIGH mode is: engine 10 → crankshaft 22 → torque converter 24 → main input shaft 26 → HIGH friction clutch 34b → first speed increasing gear 40 → third speed reducing gear 48 → LOW The side dog clutch 50 → the intermediate output shaft 46 → the first final drive gear 52 → the final driven gear 56 → the differential mechanism 54 → the output shaft 58 → the drive wheel 12. That is, even in the direct connection HIGH mode, the belt 32c of the continuously variable transmission mechanism 32 is bypassed, in other words, the torque of the engine 10 can be transmitted to the output shaft 58 (and the drive wheels 12) without passing through the belt 32c. it can.

As is clear from the above, in the continuously variable transmission T according to the embodiment of the present invention, when the speed ratio from the first pulley 32a to the second pulley is set to the minimum speed ratio, the LOW mode is set. The value of the transmission ratio of the torque transmission path in the high mode and the value of the transmission ratio of the torque transmission path in the HIGH mode are the same, in other words, the minimum transmission ratio in the LOW mode and the maximum transmission ratio in the HIGH mode are the same value. Set to

Further, since the LOW-side dog clutch 50 and the HIGH-side dog clutch 62 respectively inserted in the first and second output paths are both meshing clutches, the engagement / release operation of these clutches is performed on the input side of the clutch. This is executed when the differential rotation on the output side becomes zero. Therefore, the minimum speed ratio in the LOW mode (maximum speed ratio in the HIGH mode) is the speed ratio (switching speed ratio) when the switching control between the LOW mode and the HIGH mode is executed.

Needless to say, the value of the gear ratio in the direct connection LOW mode and the direct connection HIGH mode established during the transition to the LOW mode and the HIGH mode is the same as the switching gear ratio.

Since the details of the shift mode switching control described above are described in Japanese Patent Application No. 2014-043441 previously proposed by the present applicant, further explanation is omitted. Also, switching control from the HIGH mode to the LOW mode is achieved by the same processing.

A range selector 70 is provided at the vehicle driver's seat, and the driver selects one of the ranges such as P (parking), R (reverse), N (neutral), D (forward), etc., for example, a forward / reverse switching mechanism. 44 is switched. That is, the range selection by the driver's operation of the range selector 70 is transmitted to the manual valve of the transmission hydraulic pressure supply mechanism 72, and the vehicle 14 travels forward or backward when the travel range D or R is selected, and does not travel When P or N as the range is selected, transmission of driving force (torque) from the engine 10 to the driving wheel 12 is cut off.

FIG. 2 is a hydraulic circuit diagram of the transmission hydraulic pressure supply mechanism 72.

As shown in the figure, the transmission hydraulic pressure supply mechanism 72 is provided with a hydraulic pump 72a. The hydraulic pump 72a is a gear pump, is driven by the engine (E) 10, pumps up the hydraulic oil stored in the reservoir 72b, and pumps it to the PH control valve (PH REG VLV) 72c.

On the other hand, the output of the PH control valve 72c (PH pressure (line pressure). High pressure control hydraulic pressure) is sent to the TC regulator valve (TC） REG VLV) 72d via the oil passage L1, and the output of the TC regulator valve 72d is LC controlled. It is connected to an LC shift valve (LC SFT VLV) 72f through a valve (LC CTL VLV) 72e.

The LC shift valve 72f is controlled by the current supplied to the LC solenoid (SOL-LC) 72g, and the output of the LC shift valve 72f is connected to the piston chamber 24c1 of the lockup clutch 24c of the torque converter 24 on the one hand, Then, it is connected to the chamber 24c2 on the back side.

The output of the PH control valve 72c is sent from the oil passage L1 to the oil passage L2, and is first passed through the P1 and P2 regulator valves (P1 REG VLV, P2 REG VLV) 72h, 72i inserted in the oil passage L2. Are connected to hydraulic actuators 32a3 and 32b3 (more precisely, the piston chambers (not shown)) of the second pulleys 32a and 32b, and are connected to a CR valve (CR VLV) 72j via an oil passage L3. The

The CR valve 72j reduces the PH pressure to generate a CR pressure (control hydraulic pressure), and the generated CR pressure from the oil passage L4 to the LC linear solenoid valve (LS-LC) 72k of the LC control valve 72e and the P1, P2 linear solenoid Supply to valves (LS-P1, LS-P2) 72l, 72m.

LC linear solenoid valve 72k causes LC control valve 72e to act on the output pressure determined according to the excitation of the solenoid. Accordingly, the slip amount of the lockup clutch 24c is adjusted (controlled) by controlling the amount of current supplied to the solenoid of the LC linear solenoid valve 72m.

The P1 and P2 linear solenoid valves 72l and 72m are configured as N / C (normally closed) types, and the output pressure determined according to the excitation of the solenoids is applied to the P1 and P2 regulator valves 72h and 72i, so that oil The hydraulic oil of PH pressure sent from the path L4 is supplied to the piston chambers of the hydraulic actuators 32a3 and 32b3 as pulley hydraulic pressure (pulley side pressure) for narrowing the belt 32c. Therefore, the ratio (transmission ratio) of the continuously variable transmission mechanism 32 can be changed steplessly by controlling the amount of current supplied to the solenoid.

Also, the output (CR pressure) of the CR valve 72j is connected to the modulator valve (MOD VLV) 72n through the oil passage L5. The modulator valve 72n reduces the CR pressure to generate the MOD pressure (control oil pressure), and the generated MOD pressure from the oil passage L6 to the LOW shift valve (LO SFT VLV) 72o, the HIGH shift valve (HI SFT VLV) 72p, and the front and rear Supply to the advance shift valve (FR SHF VLV) 72q. The LOW shift valve 72o and the HIGH shift valve 72p correspond to the second solenoid valve.

LOW shift valve (LO SFT VLV) 72o, HIGH shift valve (HI SFT VLV) 72p and forward / reverse shift valve (FR SHF VLV) 72q are also configured as N / C (normally closed) types. That is, when each solenoid (LOW solenoid (SOL-L) 72r, HIGH solenoid (SOL-H) 72s, forward / reverse solenoid (SOL-FR) 72t) is energized, the spool moves to the open position and is demagnetized. And the spool closes.

The output of the LOW shift valve 72o is a LOW side meshing engagement mechanism (LOW SYNC. LOW side dog clutch 50, LOW side shift fork), more precisely, a piston chamber (not shown) of the synchronization mechanism (not shown). Connected to. When the LOW solenoid 72r is excited to open the LOW shift valve 72o and the MOD pressure is supplied to the LOW-side meshing engagement mechanism, the LOW-side shift fork operates to engage the LOW-side dog clutch 50. On the other hand, when the LOW solenoid 72r is demagnetized to close the LOW shift valve 72o and the hydraulic pressure supplied to the LOW side meshing engagement mechanism is discharged to the reservoir 72b via the LOW shift valve 72o, the LOW side shift fork Operates to release the LOW side dog clutch 50.

The output of the HIGH shift valve 72p is a HIGH-side meshing engagement mechanism (HIGH SYNC. HIGH-side dog clutch 62, HIGH-side shift fork), more precisely, the piston chamber (not shown) of the synchronization mechanism (not shown). Connected to. When the HIGH solenoid 72s is excited to open the HIGH shift valve 72p and the MOD pressure is supplied to the HIGH-side meshing engagement mechanism, the HIGH-side shift fork operates to engage the HIGH-side dog clutch 62. On the other hand, when the HIGH solenoid 72s is demagnetized and the HIGH shift valve 72p is closed, and the hydraulic pressure supplied to the HIGH meshing engagement mechanism is discharged to the reservoir 72b via the HIGH shift valve 72p, the HIGH shift fork is released. Operates to release the HIGH side dog clutch 62.

The forward / reverse shift valve 72q is a three-way valve whose output is connected on the one hand to the piston chamber (not shown) of the synchronization mechanism on the forward travel side and on the other hand the piston chamber (not shown) of the synchronization mechanism on the reverse travel side. Connected). That is, by appropriately controlling the current supplied to the forward / reverse solenoid 72t, the forward / reverse shift valve 72q is opened so as to be connected to the forward or backward piston chamber of the forward / reverse switching mechanism (F / R SYNC) 44. When the MOD pressure is supplied to any of the piston chambers, the dog clutch of the forward / reverse switching mechanism 44 is engaged with the second speed increasing gear on the forward travel side or the reverse drive gear 44a on the reverse travel side. When the forward / reverse solenoid 72t is demagnetized, the dog clutch of the forward / reverse switching mechanism 44 is released and moves to the neutral position.

The oil passage L6 is provided with a shift accumulator (SFT ACM) 72u that accumulates the hydraulic pressure generated by the oil pump 72a, and the shift valves (LOW shift valve 72o, HIGH shift valve 72p, forward / reverse shift valve 72q) described above. Assist the hydraulic pressure supplied to the.

A LOW linear solenoid valve (LS-LO) 72v and a HIGH linear solenoid valve (LS-HI) 72w are inserted in the oil passage L7, and the output (CR pressure) of the CR valve 72j is appropriately adjusted so that the LOW friction clutch (LOW CL) 34a and HIGH friction clutch (HIGH CL) 34b (more precisely, the piston chambers 34a3, 34b3). The LOW linear shift valve 72v and the HIGH linear shift valve 72w correspond to the first solenoid valve.

That is, the output of the CR valve 72j is adjusted according to the excitation of the solenoids of the LOW linear solenoid valve 72v and the HIGH linear solenoid valve 72w, and the slip amounts (engagement force) of the LOW friction clutch 34a and the HIGH friction clutch 34b are applied to each solenoid. It is adjusted (controlled) by controlling the amount of current that is energized.

Returning to the description of FIG. 1, a crank angle sensor 74 is provided at an appropriate position such as near the camshaft (not shown) of the engine 10 and outputs a signal indicating the engine speed NE for each predetermined crank angle position of the piston. To do. In the intake system, an absolute pressure sensor 76 is provided at an appropriate position downstream of the throttle valve 16 and outputs a signal proportional to the intake pipe absolute pressure (engine load) PBA.

The actuator of the DBW mechanism 20 is provided with a throttle opening sensor 78, and outputs a signal proportional to the opening TH of the throttle valve 16 through the rotation amount of the actuator.

An accelerator opening sensor 80 is provided in the vicinity of the accelerator pedal 18 and outputs a signal proportional to the accelerator opening AP corresponding to the driver's accelerator pedal operation amount. The output of the crank angle sensor 74 and the like described above is sent to the engine controller 82.

The main input shaft 26 is provided with an NT sensor (rotational speed sensor) 84 and outputs a pulse signal indicating the rotational speed NT of the main input shaft.

The first sub input shaft 28 of the continuously variable transmission mechanism 32 is provided with an N1 sensor (rotation speed sensor; abnormality detecting means) 86, so that the rotation speed N1 of the first sub input shaft 28, in other words, the rotation of the first pulley 32a. A pulse signal corresponding to the number is output. Further, the second sub input shaft 30 is provided with an N2 sensor (rotation speed sensor, abnormality detecting means) 88, which corresponds to the rotation speed N2 of the second sub input shaft 30, in other words, according to the rotation speed of the second pulley 32b. Outputs a pulse signal.

In the vicinity of the second final drive gear 60, a vehicle speed sensor (rotational speed sensor; abnormality detecting means) 90 is provided to output a pulse signal indicating the vehicle speed V, which means the traveling speed of the vehicle 14. In addition, a range selector switch 92 is provided in the vicinity of the above-described range selector 70, and outputs a signal corresponding to the range of P, R, N, D, etc. selected by the driver.

Therefore, when a signal indicating a position such as P, R, or D is output from the range selector switch 92, it can be determined that there is an in-gear instruction from the driver. Further, when a signal indicating the N position is output, it can be determined (detected) that an outgear instruction has been issued from the driver.

In the transmission hydraulic pressure supply mechanism 72, hydraulic pressure sensors 94a and 94b are respectively disposed in the oil passages communicating with the first and second pulleys 32a and 32b of the continuously variable transmission mechanism 32, and the hydraulic pressures of the first and second pulleys 32a and 32b are respectively provided. A signal corresponding to the hydraulic pressure supplied to the piston chambers of the actuators 32a3 and 32b3 is output. In addition, oil pressure sensors 94c and 94d (abnormality detection means) are respectively provided in the oil passages connected to the LOW / HIGH friction clutches 34a and 34b, and oil pressure sensors 94e and 94f are provided in the oil passages connected to the LOW side / HIGH side dog clutches 50 and 62, respectively. (Abnormality detection means) is arranged to output a signal corresponding to the hydraulic pressure supplied to each piston chamber. Although not shown in the drawings, hydraulic sensors are also arranged in the oil passages connected to the piston chamber of the clutch of the forward / reverse switching mechanism 44 and the piston chamber of the lockup clutch of the torque converter 24, respectively, and correspond to each supply hydraulic pressure. Output a signal.

LOW side / HIGH side meshing engagement mechanism, more specifically, first and second stroke sensors 96, 98 are provided near the LOW side / HIGH side dog clutches 50, 62, and the LOW side / HIGH side dog clutch. A signal corresponding to the amount of movement of 50 and 62 is output.

The output of the NT sensor 84 and the like described above is sent to the shift controller 100 (control means) including the output of other sensors (not shown). The engine controller 82 and the shift controller 100 include a microcomputer including a CPU, a ROM, a RAM, an I / O, and the like, and are configured to be able to communicate with each other.

The engine controller 82 determines the target throttle opening based on the sensor output described above to control the operation of the DBW mechanism 20, determines the fuel injection amount and the ignition timing, and controls the operation of an ignition device such as an injector or a spark plug. To do.

The shift controller 100 calculates the pulley side pressure based on the outputs of the hydraulic sensors 94a and 94b, and excites and demagnetizes the P1 and P2 linear solenoid valves 72l and 72m in accordance with the calculated side pressure to thereby generate the first and second pulleys 32a and 32a. The operation of the continuously variable transmission mechanism 32 is controlled by controlling the supply and discharge of the hydraulic pressure to and from the piston chambers of the hydraulic actuators 32a3 and 32b3 of 32b, and the operations of the forward / reverse switching mechanism 44 and the torque converter 24 are controlled.

The above is the configuration of the continuously variable transmission T according to the embodiment of the present invention. Here, the problem to be solved by the present invention will be described again. As shown in FIG. 2, the continuously variable transmission having a plurality of torque transmission paths is provided. In the transmission T, when the switching mechanism for switching the torque transmission path is controlled by a solenoid valve, if an abnormality occurs in the solenoid valve, it becomes difficult to appropriately control the switching mechanism and the continuously variable transmission mechanism 32. There is a risk of impairing sex.

Even if there is no abnormality in the solenoid valve, the same inconvenience as described above can occur when an abnormality such as sticking occurs in the switching mechanism itself.

Therefore, in the embodiment of the present invention, the first solenoid valve (LOW linear shift valve 72v, HIGH linear shift valve 72w) for controlling the input path switching mechanism 34, and the second solenoid valve (LOW) for controlling the output path switching mechanism. Solenoid valve 72o, HIGH solenoid valve 72p) and the switching mechanism itself (more specifically, LOW / HIGH friction clutches 34a, 34b, LOW side / HIGH side dog clutches 50, 62) are abnormal. Even if it exists, the control device of the continuously variable transmission T which improved the durability was provided.

FIG. 3 is a flow chart for explaining the operation (control) of the continuously variable transmission T executed by the shift controller 100 in order to solve such a problem, and FIG. 4 is for explaining an abnormal form that can be detected by the processing described later. It is explanatory drawing. Note that the processing in FIG. 3 is repeatedly executed at predetermined time intervals.

Describing below, in S10, it is determined whether or not switching control of the transmission mode (torque transmission path) of the continuously variable transmission T is being executed (S: processing step). Although not shown, the shift controller 100 uses a shift map prepared in advance based on the accelerator opening AP and the vehicle speed V obtained from the outputs of the accelerator opening sensor 80 and the vehicle speed sensor 90 prior to the determination in S10. The target speed ratio of the continuously variable transmission T is calculated by searching, and it is determined whether or not the speed change mode of the continuously variable transmission T should be switched based on the calculated target speed ratio.

When the result in S10 is negative, there is no need to switch the speed change mode of the continuously variable transmission T. Therefore, the process proceeds to S12 and normal speed change control is executed. On the other hand, if the result in S10 is affirmative, the process proceeds to S14, and it is determined whether or not the switching determined to be necessary in S10 is switching from the LOW mode to the HIGH mode.

When the result in S14 is affirmative, the program proceeds to S16, in which the input path switching mechanism 34 (LOW / HIGH friction clutch 34a, 34b), the output path switching mechanism (LOW side / HIGH side dog clutch 50, 62), the first solenoid valve (LOW / It is detected whether or not an abnormality has occurred in any of the HIGH linear solenoid valves 72v, 72w) and the second solenoid valve (LOW / HIGH solenoid valves 72o, 72p).

Here, the assumed abnormal form will be described with reference to FIG. 4A is a table in which abnormal forms are detected for each part to be detected, according to a shift pattern at the time of abnormality detection, and FIG. 4B is a shift mode in which the abnormal form is shifted after the abnormality is detected. FIG. 7 is a table in which these are summarized according to the shift pattern when an abnormality is detected, and are distributed as an abnormal pattern.

In FIG. 4, L fixation means an abnormal form in which the LOW-side dog clutch 50 is fixed in the engaged state. Further, the H fixation means an abnormal form in which the HIGH side dog clutch 62 is fixed in the engaged state, and the N fixation means an abnormal form in which the LOW side / HIGH side dog clutches 50 and 62 are fixed in the released state. Since the solenoid valves (LOW / HIGH linear solenoid valves 72v, 72w, LOW / HIGH solenoid valves 72o, 72p) are all N / C type, the disconnection failure is closed and the short-circuit failure is locked in the open state. Means abnormal form. Further, ON fixation means an abnormal form in which the LOW / HIGH friction clutches 34a and 34b are fixed in an engaged state. In addition, although illustration is abbreviate | omitted, in a LOW side / HIGH side meshing engagement mechanism, a detent is provided in an engagement position and a releasing position. Therefore, for example, when the LOW solenoid valve 72o is disconnected during traveling in the LOW mode, the LOW-side dog clutch 50 is held in the engaged state by the detent.

In FIG. 4, the LOW friction clutch 34a is “LOW clutch”, the HIGH friction clutch 34b is “HIGH clutch”, the LOW side dog clutch 50 is “LOW side dog”, and the HIGH side dog clutch 62 is “HIGH side dog”. The LOW linear solenoid valve 72v is “L / S LOW”, the HIGH linear solenoid valve 72w is “L / S HIGH”, the LOW solenoid valve 72o is “SOL-L”, and the HIGH solenoid valve 72p is “SOL-H”. Represent each.

As shown in FIG. 4B, in S16 of FIG. 3, it is detected whether or not an abnormality corresponding to any of the abnormality patterns 1, 2, and 3 has occurred. It should be noted that a known technique can be applied to specific detection means for each abnormal form. For example, each engagement element (from the outputs of the NT sensor 84, N1 sensor 86, N2 sensor 88, and vehicle speed sensor 90) ( LOW / HIGH friction clutches 34a, 34b, LOW side / HIGH side dog clutches 50, 62), based on the difference in input / output rotational speed and the value of the hydraulic pressure supplied to each solenoid valve obtained from the output of the hydraulic sensors 94c to 94f, It is possible to detect whether or not an abnormality has occurred.

If it is determined in S16 of FIG. 3 that there is no abnormality (failure) that hinders at least switching control from the LOW mode to the HIGH mode, the program proceeds to S12 and normal shift switching control is performed. Do. On the other hand, when an affirmative determination is made in S16 and an abnormality is detected, the program proceeds to S18 to execute the switching control to the direct connection mode.

More specifically, as shown in FIG. 4B, when the abnormal form detected in S16 corresponds to the abnormal pattern 1 or 2, the mode of the continuously variable transmission T is shifted to the direct connection HIGH mode (switched). ). That is, as is apparent from the specific abnormal forms corresponding to the abnormal patterns 1 and 2, the abnormal patterns 1 and 2 indicate that the HIGH friction clutch 34b or the LOW side dog clutch 50 is engaged, or the LOW friction clutch 34a or the HIGH side dog clutch. 62 means that it is locked in the released state. Therefore, when the abnormal pattern 1 or the abnormal pattern 2 is detected, the direct connection HIGH mode (HIGH friction clutch 34b and LOW side dog clutch 50 engagement, LOW friction clutch 34a and HIGH side dog clutch 62 release) is selected.

However, in the direct connection HIGH mode, the torque of the engine 10 is transmitted to the output shaft 58 via the high-speed input path, but the speed change control via the continuously variable transmission mechanism 32 cannot be performed. In view of fuel consumption and fuel consumption, it is not always preferable to maintain the direct connection HIGH mode. Therefore, although not shown in the flow chart of FIG. 3, in the embodiment of the present invention, when the abnormal form corresponds to the abnormal pattern 1, the mode of the continuously variable transmission T is switched to the direct connection HIGH mode. Thereafter, when the vehicle 14 stops, the mode of the continuously variable transmission T is shifted to the LOW mode (switched).

That is, the abnormal pattern 1 means that the LOW side dog clutch 50 is engaged or locked, and the HIGH side dog clutch is locked in the released state. Therefore, if the abnormal pattern 1 is detected, the vehicle 14 After stopping, it becomes possible to shift to the LOW mode (engagement of the LOW friction clutch 34a and the LOW side dog clutch 50, release of the HIGH friction clutch 34b and the HIGH side dog clutch). On the other hand, the abnormal pattern 2 means that the LOW friction clutch 34a is locked in the released state and the HIGH friction clutch 34b is locked in the engaged state. Therefore, when the abnormal pattern 2 is detected, the transition to the LOW mode is not performed. Therefore, the direct connection HIGH mode is maintained.

Further, when the abnormal form detected in S16 corresponds to the abnormal pattern 3, the mode of the continuously variable transmission T is shifted (switched) to the direct connection LOW mode. That is, the abnormal pattern 3 means a case where the LOW friction clutch 34a is locked in the engaged state or the HIGH friction clutch 34b is released, so that when the abnormal pattern 3 is detected, the direct connection LOW mode ( LOW friction clutch 34a and HIGH side dog clutch 62 engagement, HIGH friction clutch 34b and LOW side dog clutch 50 release) are selected. When the direct connection LOW mode is selected in S18, switching to another mode is prohibited thereafter.

On the other hand, if the determination in S14 is negative, that is, if it can be determined that the switching determined to be necessary in S10 is switching from the HIGH mode to the LOW mode, the program proceeds to S20 and the input path switching mechanism 34 (LOW / HIGH friction clutch 34a). 34b), output path switching mechanism (LOW side / HIGH side dog clutch 50, 62), first solenoid valve (LOW / HIGH linear solenoid valve 72v, 72w), second solenoid valve (LOW / HIGH solenoid valve 72o, 72p). It is detected whether an abnormality has occurred in any of the above.

More specifically, as is apparent from FIG. 4B, in S20, it is detected whether an abnormality corresponding to the abnormal pattern 4 or the abnormal pattern 5 has occurred.

If the result in S20 is NO, that is, if it is determined that at least an abnormality (failure) that hinders switching control from the HIGH mode to the LOW mode has not occurred, the program proceeds to S22 and performs normal shift switching control. On the other hand, when the result in S20 is affirmative, the program proceeds to S24 and executes control for switching to the direct connection mode.

More specifically, as shown in FIG. 4B, when the abnormal form detected in S20 corresponds to the abnormal pattern 4, the mode of the continuously variable transmission T is shifted (switched) to the direct connection LOW mode. That is, as apparent from the specific abnormality forms corresponding to the abnormal pattern 4, the abnormal pattern 4 is in the engaged state of the LOW friction clutch 34a or the HIGH side dog clutch 62, or in the released state of the HIGH friction clutch 34b or the LOW side dog clutch 50. Means that when the abnormal pattern 4 is detected, the direct connection LOW mode is selected. If the direct connection LOW mode is selected in S24, switching to another mode is prohibited thereafter.

Further, when the abnormal form detected in S20 corresponds to the abnormal pattern 5, the mode of the continuously variable transmission T is shifted (switched) to the direct connection HIGH mode. That is, the abnormal pattern 5 means that the LOW friction clutch 34a is in the released state or the HIGH friction clutch 34b is locked in the engaged state. Therefore, when the abnormal pattern 5 is detected, the direct connection HIGH mode is selected. After that, switching to another mode is prohibited.

FIG. 5 is a state transition diagram illustrating the switching control of the torque transmission path (shift mode) described above.

As shown in FIG. 5, when the abnormal pattern 1 or the abnormal pattern 2 is detected during execution of the switching control from the LOW mode to the HIGH mode, the mode of the continuously variable transmission T is switched to the direct connection HIGH mode. When 3 is detected, the mode is switched to the direct connection LOW mode. Further, during the execution of switching control from the HIGH mode to the LOW mode, when the abnormal pattern 4 is detected, the mode of the continuously variable transmission T is switched to the direct connection LOW mode, while when the abnormal pattern 5 is detected, the direct connection HIGH is performed. Switch to mode.

Further, when the abnormal pattern 1 is detected, when the vehicle 14 stops after switching to the direct connection HIGH mode, switching to the LOW mode is executed, and thereafter the LOW mode is maintained. Further, when other abnormal patterns (abnormal patterns 2 to 4) are detected, the mode is maintained (switching to other modes is prohibited) after the mode switching described above.

As described above, in the embodiment of the present invention, the main input shaft (input shaft) 26 connected to the engine (drive source, internal combustion engine) 10 mounted on the vehicle 14, the first pulley 32a, and the second pulley 32b. And an endless flexible member (for example, a belt) 32c wound around the first pulley 32a and the second pulley 32b, and connected to the main input shaft 26 and the drive wheel 12 of the vehicle 14. A continuously variable transmission mechanism 32 that is inserted between the output shaft 58 and continuously changes the torque (driving force) of the engine 10 that is input from the main input shaft 26 and that is input from the main input shaft 26. A low speed stage input path for inputting the torque of the engine 10 to the first pulley 32a and a high speed stage input for inputting the torque of the engine 10 input from the main input shaft 26 to the second pulley 32b. An input path switching mechanism 34 (LOW / HIGH friction clutches 34a, 34b) for selectively switching a path and an input path to which torque input from the main input shaft 26 is transmitted among the low speed stage and the high speed stage input path. And a first solenoid valve (LOW / HIGH linear solenoid valve 72v, 72w) for operating the input path switching mechanism 34 and the second pulley 32b, and via the low speed stage input path and the belt 32c. A first output path for outputting the torque transmitted to the output shaft 58, and the torque transmitted to the first pulley 32a via the high-speed stage input path and the belt 32c. A second output path that outputs to the output shaft 58 and the first and second output paths are transmitted via the belt 32c. An output path switching mechanism (LOW side / HIGH side dog clutches 50, 62) that selectively switches the output path to output the torque to the output shaft 58, and a second solenoid valve (LOW /) that operates the output path switching mechanism. HIGH solenoid valves 72o, 72p) and a target gear ratio of the continuously variable transmission T according to the running state of the vehicle 14, and the input path switching mechanism 34 and the like based on the calculated target gear ratio. Based on the determination by the switching determination means (shift controller 100, S10) for determining whether or not to switch at least one of the output path switching mechanisms, the operation of the first and second solenoid valves is controlled. And a control device (shift control) for the continuously variable transmission T including control means (shift controller 100) In the first shift mode (LOW), the continuously variable transmission T transmits the torque of the engine 10 to the output shaft 58 via the low speed input path, the belt 32c, and the first output path. Mode), a second speed change mode (HIGH mode) for transmitting to the output shaft 58 via the high speed input path, the belt 32c and the second output path, and transmitting to the output shaft 58 by bypassing the belt 32c. It has a direct connection mode (first and second direct connection modes), and the control means detects an abnormality in at least one of the input path switching mechanism 34, the output path switching mechanism, and the first and second solenoid valves. Abnormality detecting means (NT sensor 84, N1 sensor 86, N2 sensor 88, vehicle speed sensor 90, hydraulic sensors 94c to 94f. S16, S20), and when it is determined by the switching determination means that at least one of the input path switching mechanism 34 and the output path switching mechanism should be switched (YES in S10), the input by the abnormality detection means When abnormality in at least one of the path switching mechanism 34, the output path switching mechanism, and the first and second solenoid valves is detected (YES in S16 or S20), the continuously variable transmission T is switched to the direct connection mode. (S18, S24). That is, the switching mechanism (LOW / HIGH friction clutches 34a, 34b, LOW side / HIGH side dog clutches 50, 62, LOW side / HIGH side shift fork) itself and the solenoid valve (LOW / HIGH linear solenoid valve 72v, 72w, LOW / HIGH solenoid valves 72o, 72p) are detected (failure), the torque of the engine 10 is transmitted without passing through the torque transmission member (for example, the belt 32c) of the continuously variable transmission mechanism 32. Since the direct connection mode is selected, wear of the switching mechanism and the belt 32c can be effectively suppressed even when a solenoid valve abnormality is detected. The durability of 32c can be improved.

In particular, in a continuously variable transmission having a plurality of torque transmission paths (first and second transmission modes) via the continuously variable transmission mechanism 32, the abnormality of the solenoid valve is not only the operation (control) of the switching mechanism. Also, the control of the continuously variable transmission mechanism 32 is made difficult. However, in the embodiment of the present invention, when abnormality of the switching mechanism or the solenoid valve is detected, the torque of the engine 10 can be transmitted to the output shaft 58 without using the belt 32c of the continuously variable transmission mechanism 32 or the like. Since the direct connection mode is selected, wear of the switching mechanism, the belt 32c, and the like can be effectively suppressed, and thus durability of the switching mechanism, the belt 32c, and the like can be improved.

The direct connection mode includes a first direct connection mode (direct connection LOW mode) in which torque of the engine 10 is transmitted to the output shaft 58 via at least the low speed stage input path and the second output path, and the high speed stage input path. And a second direct connection mode (direct connection HIGH mode) for transmitting the torque of the engine 10 to the output shaft 58 via the first output path, and the control means detects the input path detected by the abnormality detection means. Depending on the abnormality (abnormal pattern) of the switching mechanism 34, the output path switching mechanism, and the first and second solenoid valves, the continuously variable transmission T is switched to either the direct connection LOW mode or the direct connection HIGH mode (S14- S24). Therefore, it is possible to select the direct connection mode as appropriate according to the detected abnormality (abnormal pattern) and quickly switch to the direct connection mode, thereby further improving the durability of the switching mechanism and the belt 32c. It becomes.

The control means is the input path switching mechanism detected by the abnormality detection means when the continuously variable transmission T is stopped after the continuously variable transmission T is switched to the direct connection HIGH mode. 34, when the vehicle 14 is determined to be in a predetermined state, more specifically, in the state of the abnormal pattern 1, based on the abnormality of the output path switching mechanism and the first and second solenoid valves, The continuously variable transmission T is switched to the LOW mode, and the LOW mode is maintained (S14 to S18). That is, when it is determined that the continuously variable transmission T is in a predetermined state (the state of the abnormal pattern 1) that can be switched to the LOW mode based on the detected abnormality, the continuously variable transmission T is set to the LOW mode. As described above, since the switching mechanism and the belt 32c can be further improved in durability as described above, the shift control via the continuously variable transmission mechanism 32 can be appropriately executed. It is also possible to prevent the start performance and fuel consumption of the vehicle 14 from deteriorating.

In the above-described embodiment, the specific configuration of the continuously variable transmission T has been described. However, the configuration in FIG. 1 is merely an example, and the gist of the present invention is that the drive source is not connected to the continuously variable transmission mechanism. The continuously variable transmission T having a path for transmitting driving force to the output shaft and having a switching mechanism for selecting one torque transmission path from a plurality of torque transmission paths is also applicable to other configurations.

Further, although the belt-type continuously variable transmission mechanism has been described as an example of the continuously variable transmission mechanism 32, the invention is not limited to this, and the gist of the present invention is applicable to, for example, a chain-type continuously variable transmission mechanism.

In addition, although the friction clutch mechanism has been described as an example of the first and second input engagement mechanisms and the meshing clutch mechanism has been described as the first and second output engagement mechanisms, the present invention is not limited to this example. The output engagement mechanism may be constituted by a friction clutch.

According to the present invention, the low speed stage input path for inputting the driving force of the driving source to the first pulley of the continuously variable transmission mechanism, and the high speed stage input path for inputting the driving force of the driving source to the second pulley of the continuously variable transmission mechanism. An input path switching mechanism that switches between these input paths, a first and second output path that outputs a driving force transmitted through the endless flexible member of the continuously variable transmission mechanism to the output shaft, and these output paths In a control device for a continuously variable transmission including an output path switching mechanism for switching and first and second solenoid valves for operating the input / output path switching mechanism, the continuously variable transmission reduces the driving force of the drive source at a low speed. A first speed change mode for transmitting to the output shaft via the step input path, the endless flexible member and the first output path, and a transmission to the output shaft via the high speed stage input path, the endless flexible member and the second output path. The second speed change mode and the endless flexible member are bypassed. And a direct connection mode for transmitting to the output shaft, and the control means determines at least one of the input / output path switching mechanism and the first and second solenoid valves when switching the input / output path switching mechanism. Since the continuously variable transmission is configured to switch to the direct connection mode when an abnormality is detected, wear of the switching mechanism and the belt can be effectively suppressed even when an abnormality of the solenoid valve is detected. Therefore, the durability of the switching mechanism and the belt can be improved.

T continuously variable transmission, 10 engine (internal combustion engine, drive source), 14 vehicle, 26 main input shaft, 32 continuously variable transmission mechanism, 32a first pulley, 32b second pulley, 32c belt, 34 input path switching mechanism, 34a LOW friction clutch, 34b HIGH friction clutch, 50 LOW side dog clutch (output path switching mechanism), 58 output shaft, 62 HIGH side dog clutch (output path switching mechanism), 72 transmission hydraulic pressure supply mechanism, 72o LOW solenoid valve (second solenoid) Valve), 72p HIGH solenoid valve (second solenoid valve), 72v LOW linear solenoid valve (first solenoid valve), 72w HIGH linear solenoid valve (first solenoid valve), 84 NT sensor (abnormality detection means), 86 N1 sensor (Abnormality detection means) 88 N2 sensor (abnormality detection means), 90 a vehicle speed sensor (abnormality detection means), 94c, 94d, 94e, 94f hydraulic pressure sensor (abnormality detection means), 100 shift controller

Claims (3)

1. An input shaft connected to a drive source mounted on a vehicle, a first pulley, a second pulley, and an endless flexible member that is hung between the first pulley and the second pulley, and the input shaft And a continuously variable transmission mechanism that is inserted between the drive shaft of the vehicle and an output shaft connected to the drive wheel of the vehicle and continuously changes the driving force of the drive source input from the input shaft, and input from the input shaft A low-speed stage input path for inputting the driving force of the driving source to the first pulley, a high-speed stage input path for inputting the driving force of the driving source input from the input shaft to the second pulley, and An input path switching mechanism that selectively switches an input path to which a driving force input from the input shaft is to be transmitted among a low speed stage and a high speed stage input path; and a first solenoid valve that operates the input path switching mechanism; Connected to the second pulley Both are connected to the first pulley and the first pulley for outputting the driving force transmitted to the output shaft through the low speed stage input path and the endless flexible member, and the high speed stage input. A second output path for outputting the driving force transmitted through the path and the endless flexible member to the output shaft, and a transmission among the first and second output paths through the endless flexible member. An output path switching mechanism that selectively switches an output path to output the driving force to be output to the output shaft, a second solenoid valve that operates the output path switching mechanism, and the absence according to the traveling state of the vehicle. A switching judgment for calculating a target transmission ratio of the step transmission and determining whether or not to switch at least one of the input path switching mechanism and the output path switching mechanism based on the calculated target transmission ratio. And means, in the control device of the continuously variable transmission and a control means for controlling said first, operation of the second solenoid valve on the basis of the determination by the switching determination unit,
   The continuously variable transmission is configured to transmit a driving force of the driving source to the output shaft via the low-speed input path, an endless flexible member, and a first output path, and the high-speed input path. And a second transmission mode in which the endless flexible member is transmitted to the output shaft via the second output path, and a direct connection mode in which the endless flexible member is bypassed and transmitted to the output shaft,
   The control means includes an abnormality detection means for detecting an abnormality in at least one of the input path switching mechanism, the output path switching mechanism, and the first and second solenoid valves, and the switching determination means determines the input path. When it is determined that at least one of the switching mechanism and the output path switching mechanism should be switched, at least one of the input path switching mechanism, the output path switching mechanism, and the first and second solenoid valves is detected by the abnormality detection unit. When the abnormality is detected, the continuously variable transmission is switched to the direct connection mode.
2. The direct connection mode includes a first direct connection mode in which the driving force of the driving source is transmitted to the output shaft through at least the low speed stage input path and the second output path, and the high speed stage input path and the first output path. And a second direct coupling mode for transmitting the driving force of the driving source to the output shaft, and the control means includes the input path switching mechanism, the output path switching mechanism, and the first path detected by the abnormality detection means. 2. The control device for a continuously variable transmission according to claim 1, wherein the continuously variable transmission is switched to one of the first and second direct connection modes in response to an abnormality of the second solenoid valve.
3. The control means is a case where the continuously variable transmission stops after the continuously variable transmission is switched to the second direct connection mode, and the input path switching mechanism and the output detected by the abnormality detecting means. When it is determined that the vehicle is in a predetermined state based on an abnormality in the path switching mechanism and the first and second solenoid valves, the continuously variable transmission is switched to the first shift mode and the first 3. The continuously variable transmission control device according to claim 2, wherein the transmission mode is maintained.

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