JP2016048087A - Vehicular lockup clutch control apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular lockup clutch control apparatus capable of realizing lockup reengagement at early timing when lockup reengagement is performed in a coasting state.SOLUTION: A vehicle includes, between an engine 1 and a stepless transmission 6, a torque converter 4 including a lockup clutch 3. The vehicle further includes lockup control means (FIG. 4) for controlling to reengage the lockup clutch 3 by increasing a fuel flow for the engine 1 if the lockup clutch 3 is released in a coasting state as a result of a foot off the accelerator pedal. The lockup control means (FIG. 4) includes a casting state determination part (S6) for determining whether the vehicle is coasting on inertia, and, if a casting is determined, starts reengagement control for the lockup clutch 3.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a vehicle lock-up clutch control device that performs re-engagement control of a lock-up clutch that is released in a coasting state.

  Conventionally, when re-engagement control of a lock-up clutch is performed after fuel supply cut due to accelerator release, a device is known that performs fuel supply that increases the engine speed and realizes clutch re-engagement in a coasting state ( For example, see Patent Document 1).

JP 7-279700 A

  However, in the conventional apparatus, the lockup re-engagement control is started when the end of the upshift is determined. For this reason, even in a sliding scene where lockup re-engagement is possible, such as on a downhill road, re-engagement control is started at a late timing when the up-shift is started and the end of the up-shift is determined. There was a problem.

  The present invention has been made paying attention to the above problem, and an object of the present invention is to provide a vehicle lock-up clutch control device that realizes lock-up re-engagement at an early timing when lock-up is re-engaged in a coasting state. .

In order to achieve the above object, the present invention includes a torque converter having a lock-up clutch between an engine and a transmission.
In this vehicle, when the lockup clutch is released in a coasting state by releasing the accelerator pedal, a lockup control means is provided for performing control to re-engage the lockup clutch by increasing the amount of fuel in the engine.
The lockup control means includes a sliding state determination unit that determines whether or not the vehicle is in a sliding state that is traveling due to inertia, and when it is determined that the vehicle is in the sliding state, starts re-engagement control of the lockup clutch. .

Therefore, when the lockup clutch is released in the coasting state, it is determined whether or not it is a sliding state that is traveling due to inertia, and if it is determined that it is in the sliding state, re-engagement control of the lockup clutch Is started.
In other words, by making the sliding state the starting condition for the lockup re-engagement control, depending on the driving scene, it is earlier than when waiting for the starting condition to be established due to the elapsed time after the lockup released state is established. The lock-up re-engagement is realized.
As a result, when the lockup is reengaged in the coasting state, the lockup reengagement at an early timing can be realized.

1 is an overall system diagram showing an engine vehicle to which a lockup clutch control device of Embodiment 1 is applied. It is a shift map figure which shows an example of the shift map used by the shift control of a CVT control unit. It is a lockup map figure which shows an example of a lockup map used by the lockup clutch control of a CVT control unit. It is a flowchart which shows the flow of the lockup control processing performed in the CVT control unit of Example 1. FIG. It is a fuel increase control map figure which shows the relationship between the sliding state used by lockup control processing, and the inclination of the increase of an engine speed. In the comparative example, the accelerator, rotation speed (engine rotation speed, turbine rotation speed), fuel injection amount, L / U when starting lockup re-engagement control after waiting for the establishment of the control start condition during running in the coasting state It is a time chart which shows each characteristic of a cancellation | release flag and a lockup command signal. Acceleration, sliding degree determination, rotation speed (engine rotation speed, turbine rotation speed), fuel injection amount, L / L when starting lock-up re-engagement control by establishment of sliding determination during traveling in the coasting state in the first embodiment It is a time chart which shows each characteristic of U cancellation | release flag and a lockup command signal. In the first embodiment, when the lockup re-engagement control is started due to the establishment of the sliding determination during the running in the coasting state, the accelerator, the sliding degree determination, and the rotational speed (engine rotational speed) when the torque increase according to the sliding degree is performed. Turbine speed), fuel injection amount, L / U release flag, and lock-up command signal.

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

First, the configuration will be described.
The configuration of the vehicle lockup clutch control device according to the first embodiment will be described by dividing it into an “overall system configuration” and a “lockup control configuration”.

[Overall system configuration]
FIG. 1 shows an engine vehicle to which the lockup clutch control device of the first embodiment is applied. The overall system configuration will be described below with reference to FIG.

  As shown in FIG. 1, the vehicle drive system includes an engine 1, an engine output shaft 2, a lock-up clutch 3, a torque converter 4, a transmission input shaft 5, and a continuously variable transmission 6 (transmission). The drive shaft 7 and the drive wheel 8 are provided.

  The lock-up clutch 3 is built in the torque converter 4 and connects the engine 1 and the continuously variable transmission 6 via the torque converter 4 when the clutch is released, and directly connects the engine output shaft 2 and the transmission input shaft 5 when the clutch is engaged. To do. The lockup clutch 3 is controlled to be engaged / slip engaged / released by an L / U actual oil pressure generated based on an L / U command oil pressure from a CVT control unit 12 described later.

  The torque converter 4 includes a pump impeller 41, a turbine runner 42 disposed to face the pump impeller 41, and a stator 43 disposed between the pump impeller 41 and the turbine runner 42. The torque converter 4 is a fluid coupling that transmits torque by circulating hydraulic oil filled therein through the blades of the pump impeller 41, the turbine runner 42, and the stator 43. The pump impeller 41 is connected to the engine output shaft 2 via a converter cover 44 whose inner surface is a fastening surface of the lockup clutch 3. The turbine runner 42 is connected to the transmission input shaft 5. The stator 43 is provided on a stationary member (transmission case or the like) via a one-way clutch 45.

  The continuously variable transmission 6 is a belt-type continuously variable transmission that continuously controls the gear ratio by changing the belt contact diameter to the primary pulley and the secondary pulley, and the output rotation after the shift is via the drive shaft 7. And transmitted to the drive wheel 8.

  As shown in FIG. 1, the vehicle control system includes an engine control unit 11 (ECU), a CVT control unit 12 (CVTCU), and a CAN communication line 13. As sensors for obtaining input information, an engine speed sensor 14, a turbine speed sensor 15 (= CVT input speed sensor), a CVT output speed sensor 16 (= vehicle speed sensor), an accelerator opening sensor 17, A secondary rotational speed sensor 18, a primary rotational speed sensor 19, and other sensors / switches 20 are provided.

  The engine control unit 11 performs fuel cut control in which fuel injection to the engine 1 is stopped in a coasting state by releasing the accelerator pedal and fuel injection is restarted based on fuel recovery permission. This fuel cut control is performed by a fuel cut control unit 11a included in the engine control unit 11 and stops fuel injection by receiving a zero opening signal of an accelerator opening indicating an accelerator release from the CVT control unit 12. When the fuel injection is stopped, the fuel injection is resumed by receiving the fuel recovery permission from the CVT control unit 12.

  The CVT control unit 12 performs shift control for controlling the gear ratio of the continuously variable transmission 6, lockup clutch control for switching engagement / slip engagement / release of the lockup clutch 3, and the like.

  The basic control of the shift control is performed by a shift control unit 12 a included in the CVT control unit 12. For example, using the shift map shown in FIG. 2, when the operating point determined by the vehicle speed VSP and the accelerator opening APO moves to the low gear ratio side or the high gear ratio side, a gear shift instruction is issued and the target input speed (= target primary speed) The speed ratio is changed so as to obtain the rotation speed).

  The basic control of the lock-up clutch control is performed by the lock-up clutch control unit 12b included in the CVT control unit 12, and the lock-up map shown in FIG. 3 is used for the purpose of improving the fuel consumption in the driving state by depressing the accelerator. Done. That is, when the operating point determined by the vehicle speed VSP and the accelerator opening APO crosses the OFF → ON line in FIG. 3, an LU engagement request is issued and the unlocked lockup clutch 3 is engaged. On the other hand, when the operating point determined by the vehicle speed VSP and the accelerator opening APO crosses the ON → OFF line in FIG. 3, an LU release request is issued, and the lockup clutch 3 in the engaged state is released.

[Lockup control configuration]
FIG. 4 shows a flow of lockup control processing executed by the CVT control unit 12 of the first embodiment (lockup control means). Hereinafter, each step of FIG. 4 representing the lockup control processing configuration will be described.

In step S1, following the start of the lockup control, it is determined whether or not the lockup release state in which the lockup clutch 3 is released. If YES (lock-up released state), the process proceeds to step S2. If NO (other than the lock-up released state), the process returns to the start, and the determination in step S1 is repeated.
Here, in the lockup released state, the slip rotation speed (engine rotation speed-turbine rotation speed) of the lockup clutch 3 may be observed, or it may be determined that a predetermined time has elapsed from the lockup release command. Alternatively, it may be determined from a lockup differential pressure command value or the like.

  In step S2, following the determination that the lockup is released in step S1, the operating point based on the vehicle speed VSP and the accelerator opening APO is in the lockup engagement permission region in FIG. 3 (lockup ON region in FIG. 3). Judge whether there is. If YES (lockup fastening permission area), the process proceeds to step S3. If NO (lockup fastening permission area), the process returns to step S1.

In step S3, it is determined whether or not it is a coasting state (= coast state) by releasing the accelerator pedal, following the determination that it is the lockup fastening permission region in step S2. If YES (coast state), the process proceeds to step S4. If NO (other than the coast state), the process proceeds to step S8.
Here, the coast state may be determined using an idle switch signal or a signal related to engine torque (accelerator opening signal or the like).

  In step S4, following the determination that the coast state is in step S3 or the coasting state in step S7, the lock-up engagement is exceptionally performed while the operating point is in the lock-up engagement permission region. Based on the operation of the lockup prohibition control to be prohibited, a lockup release instruction is output, and the process proceeds to step S5.

In step S5, following the output of the lockup release instruction in step S4, it is determined whether a control start condition for starting lockup re-engagement control of the released lockup clutch 3 is satisfied. If YES (control start condition is satisfied), the process proceeds to step S9. If NO (control start condition is not satisfied), the process proceeds to step S6.
Here, the control start condition of the lock-up re-engagement control can include, for example, that a predetermined time has passed in the coasting state. In addition, it may be a condition that the engine speed, the turbine speed, and the engine torque are in a stable state, or an elapsed time condition and a rotation / torque stabilization condition may be combined.

In step S6, following the determination that the control start condition is not satisfied in step S5, it is determined whether or not the vehicle is in a running state due to inertia. If YES (sliding state), the process proceeds to step S9, and if NO (not sliding state), the process proceeds to step S7 (sliding state determination unit).
Here, the sliding state refers to a coast state in which the lock-up clutch 3 is released and a state where the vehicle is coasting at a constant speed or an acceleration state without being decelerated or stopped. The sliding state is determined from, for example, a road surface gradient (when downhill), vehicle acceleration (when it is not decelerated or stopped), and the like. The road surface gradient and vehicle acceleration are calculated from information from the navigation system, means such as an external sensor or a sensor in the vehicle. Note that the threshold value for determining that the vehicle is in the sliding state is variable depending on the drivability.

In step S7, it is determined whether or not the vehicle is in a driving state by depressing the accelerator, following the determination in step S6 that the vehicle is not in the sliding state. If YES (during driving), the process proceeds to step S8. If NO (coasting), the process returns to step S4.
Here, the determination of whether or not the vehicle is being driven may be made by looking at the accelerator operation or by using the throttle opening or the like. Alternatively, it may be determined from the relationship between the engine speed and the turbine speed (engine speed> turbine speed, etc.).

In step S8, following the determination in step S3 or step S7 that driving is in progress, normal lockup control is performed, and the process proceeds to the end.
Here, the normal lockup control refers to the engagement / release control of the lockup clutch 3 that is performed based on the lockup map of FIG.

In step S9, it is determined that the control start condition is satisfied in step S5, or it is determined that the vehicle is in the sliding state in step S6, or it is determined that the lock-up engagement is not possible in step S10. Subsequently to the fuel recovery permission, fuel increase control (engine torque up) of the engine 1 is performed, and the process proceeds to step S10.
Here, in the fuel increase control of the engine 1, as shown in FIG. 5, control is performed to increase the slope of increase in the engine speed as the sliding state is stronger. In the case of a road surface gradient, the degree of the sliding state is determined to be stronger as the descending slope angle is larger, and in the case of vehicle acceleration, it is determined that the higher the vehicle acceleration is, the stronger the sliding state is.

In step S10, following the fuel increase control in step S9, it is determined whether or not lock-up fastening is possible. If YES (state in which lock-up engagement is possible), the process proceeds to step S11. If NO (state in which lock-up engagement is not possible), the process returns to step S9.
Here, the determination that the lock-up engagement is possible is, for example, that the differential rotational speed between the clutch input rotational speed and the clutch output rotational speed is equal to or less than the differential rotational speed threshold set to a value that can suppress the engagement shock. Judge by.

  In step S11, following the determination in step S10 that the lock-up engagement is possible, or the determination in step S12 that the lock-up engagement has not been completed, a lock-up engagement instruction by operating the lock-up solenoid is issued. Output, and go to step S12.

In step S12, following the output of the lockup engagement instruction in step S11, it is determined whether or not the lockup engagement is complete. If YES (lock-up engagement is complete), the process proceeds to the end. If NO (lock-up engagement is not completed), the process returns to step S11.
Here, the determination of completion of lockup engagement may be performed by looking at the slip rotation speed (engine rotation speed-turbine rotation speed) or by determining that a predetermined time has elapsed from the lockup engagement command. Further, it may be determined from a lockup differential pressure command value or the like.

Next, the operation will be described.
The operation of the lockup clutch control device of the first embodiment will be described separately for “lockup control processing operation” and “lockup re-engagement control start operation by sliding determination”.

[Lock-up control processing action]
Hereinafter, the lockup control processing operation of the first embodiment will be described based on the flowchart shown in FIG.
In a coasting scene where the vehicle speed VSP is high with the lock-up clutch 3 not fully engaged, the process proceeds from step S1 to step S2 to step S3 to step S4 in the flowchart of FIG. In step S4, a lockup release instruction is output based on the operation of the lockup prohibition control. If the control start condition of the clutch re-engagement control is not satisfied, and the coasting state is not maintained and the coasting state is maintained, the flow from step S4 to step S5 to step S6 to step S7 is repeated. The output of the lockup release instruction is maintained. When the accelerator depression operation is intervened while the lockup release is maintained and the coasting state is shifted to the drive state, the process proceeds from step S7 to step S8, and the normal lockup control is returned.

  That is, if YES is determined in all of steps S1 to S3, the lockup release control is activated by the lockup prohibition control by the “coast running scene in a state where the lockup clutch 3 is not completely engaged” is activated. An instruction is output. In this case, when a lockup fastening instruction is continued in the lockup released state and the coasting state, a fastening shock or the like occurs at the time of lockup fastening. At this time, even if the fastening shock itself is small, the shock sensitivity of the occupant is high in the coasting state by the accelerator release operation. On the other hand, when the lock-up clutch 3 is released in the coasting scene, the uncomfortable feeling of driving operation can be eliminated.

  On the other hand, for example, assume that it is determined in step S6 that the vehicle is in a sliding state while the lockup release is being maintained. In this case, the process proceeds from step S6 to step S9 to step S10 in the flowchart of FIG. Then, as long as it is determined in step S10 that lock-up fastening is impossible, the flow from step S9 to step S10 is repeated. In step S9, the fuel increase control (engine torque up) of the engine 1 is performed so that the gradient of increase in the engine speed increases as the sliding state increases.

  When it is determined in step S10 that the differential rotation of the lockup clutch 3 has converged and the lockup engagement is possible, the process proceeds from step S10 to step S11 to step S12 in the flowchart of FIG. Then, as long as it is determined in step S12 that lock-up engagement has not been completed, the flow from step S11 to step S12 is repeated. In this step S11, a lock-up fastening instruction by the operation of the lock-up solenoid is output. When it is determined in step S12 that the lockup clutch 3 is not slipped and the engagement torque capacity is increased and the lockup engagement is complete, the process proceeds from step S12 to the end in the flowchart of FIG.

  On the other hand, for example, when it is determined that the predetermined time has elapsed since the lockup clutch 3 was released in the coasting state without being determined to be in the sliding state, the control start condition of the clutch reengagement control is satisfied in step S5. Suppose that it is determined. In this case, the process proceeds from step S5 to step S9 to step S10 in the flowchart of FIG. Then, as long as it is determined in step S10 that lock-up fastening is impossible, the flow from step S9 to step S10 is repeated. In this step S9, for example, fuel increase control (engine torque up) of the engine 1 by a predetermined fuel increase is performed. The process of step S11 and step S12 is the same as the case where it is judged that it is a sliding state and lockup re-engagement control is started.

[Lock-up re-engagement control start action by sliding judgment]
Hereinafter, the lockup re-engagement control start action by the sliding determination of the first embodiment will be described based on the time charts shown in FIGS.

  An example in which the start condition of the lock-up re-engagement control in the coasting state in which the lock-up clutch is released is used as the elapsed time condition is a comparative example. The lockup re-engagement control start action in this comparative example will be described with reference to the time chart shown in FIG. In FIG. 6, time t1 is the lock-up release time, time t2 is the re-engagement control start time, and time t3 is the lock-up re-engagement time.

  That is, when the accelerator release operation is performed at time t1, the lockup control prohibition condition is satisfied, the lockup engagement instruction is switched to the lockup release instruction, the engine fuel cut is performed, and the lockup clutch Is released. When the lock-up clutch is released at time t1, the engine speed of the fuel-cut engine decreases due to a steep slope, whereas the CVT input speed (== Turbine speed) decreases due to a gentle gradient, and the turbine speed and engine speed deviate toward time t2. Then, by waiting for a sufficient elapsed time from time t1 to time t2, when the start condition of the re-engagement control of the lockup clutch is satisfied at time t2, the engine fuel supply amount increase control is started, and from time t2 The engine speed starts to rise. At time t3, the engine speed converges to the turbine speed, and the lockup clutch is re-engaged.

  Therefore, the elapsed time ΔTL1 from the lock-up release time t1 to the re-engagement start time t2 becomes long, and the re-engagement timing of the lock-up clutch is delayed, so that the engine braking force cannot be obtained quickly. Further, when the difference between the turbine speed and the engine speed becomes large at time t2, the amount of torque increase by the engine increases, so that the amount of fuel supplied to the engine increases and the fuel consumption deteriorates.

  On the other hand, in Example 1, it is set as the structure which starts re-engagement control of the lockup clutch 3 if it determines with it being a sliding state in step S6. The lockup re-engagement control start action by the sliding determination will be described with reference to a time chart shown in FIG. In FIG. 7, time t1 is the lock-up release time, time t2 is the re-engagement control start time, and time t3 is the lock-up re-engagement time.

  That is, when the accelerator release operation is performed at time t1, the lock-up control prohibition condition is satisfied, the lock-up engagement instruction is switched to the lock-up release instruction, and the fuel cut of the engine 1 is performed and the lock-up is performed. The clutch 3 is released. When the lockup clutch 3 is released at time t1, the engine speed of the fuel-cut engine decreases due to a steep slope, whereas the CVT input rotation that is rotated by the drive wheels 8 via the continuously variable transmission 6 The number (= turbine speed) decreases due to the gentle gradient. When the sliding determination is established at time t2, the lockup re-engagement control is started at time t2, and the engine speed starts to increase from time t2 by the engine fuel supply increase control. At time t3, the engine speed converges to the turbine speed, and the lockup clutch is re-engaged.

  Therefore, the elapsed time ΔTL2 from the lock-up release time t1 to the re-engagement start time t2 becomes short, and lock-up re-engagement at an early timing can be realized at the time of lock-up re-engagement in the coasting state. This is because, in the sliding state due to coasting, the discomfort to the drivability given to the driver becomes dull compared to when decelerating and stopping, etc., so lockup re-engagement control is started at an earlier timing than the comparative example. It uses what can be done.

  The elapsed time ΔTL2 from the lockup release time t1 to the re-engagement start time t2 can be shortened, so that the engine braking force can be quickly obtained at time t3. Furthermore, by shortening the elapsed time ΔTL2, the difference between the turbine speed and the engine speed is small, the fuel supply time to the engine 1 is shortened, the engine torque increase amount can be reduced, and fuel cut can be accelerated. This can improve fuel efficiency.

  In the first embodiment, when it is determined that the vehicle is in the sliding state, the fuel increase control is performed to increase the engine speed increase gradient as the sliding state is stronger. The lockup re-engagement control start action by this sliding determination will be described with reference to the time chart shown in FIG. In FIG. 8, time t1 is the lock-up release time, time t2 is the re-engagement control start time, time t3 is the lock-up re-engagement time when the increasing gradient of the engine speed is increased, and time t4 is the engine speed. This is the lock-up re-engagement time when the increase slope is reduced.

  That is, when the accelerator release operation is performed at time t1, the lock-up control prohibition condition is satisfied, the lock-up engagement instruction is switched to the lock-up release instruction, and the fuel cut of the engine 1 is performed and the lock-up is performed. The clutch 3 is released. When the lockup clutch 3 is released at time t1, the engine speed of the fuel-cut engine decreases due to a steep slope, whereas the CVT input rotation that is rotated by the drive wheels 8 via the continuously variable transmission 6 The number (= turbine speed) decreases due to the gentle gradient. When the sliding determination is established at time t2, the lockup re-engagement control is started at time t2, and the engine speed starts to increase from time t2 by the engine fuel supply increase control. At this time, when the sliding state is strong and the increasing slope of the engine speed is increased, at time t3, the engine speed converges to the turbine speed and the lockup clutch is re-engaged. On the other hand, when the sliding state is weak and the increasing slope of the engine speed is reduced, at time t4, the engine speed converges to the turbine speed and the lockup clutch is re-engaged.

  That is, as shown in FIG. 5, when the sliding determination is established, the increase gradient of the engine speed is increased as the sliding state is stronger, and the engine speed is increased to an engine speed that can be fastened again at an early stage. A large increase in engine speed means that the engine torque is large. However, when the vehicle is accelerating on a downward slope in the coasting state, it is possible to increase the engine torque increase amount at the time of lock-up re-engagement because the driver feels a little strange to the shock. If the engine torque increase amount is increased, the engine speed quickly increases to the target, so that lockup re-engagement can be realized at an early stage. In this way, by performing fuel increase control that increases the engine speed increase gradient as the sliding state is stronger, it is possible to achieve early lock-up re-engagement without giving the driver a sense of incongruity.

In the first embodiment, when it is determined that the elapsed time condition from the lock-up release in step S5 is satisfied, the re-engagement control of the lock-up clutch 3 is started regardless of the determination result of the sliding state in step S6. It is configured to do.
For example, if only the sliding condition is set as the start condition for the lock-up re-engagement control, the lock-up clutch 3 remains released in a driving scene that is not determined to be in the sliding state, and the engine brake request is met. I can't.
On the other hand, by setting the elapsed time condition and the sliding condition as the start conditions for the lockup re-engagement control, when the elapsed time condition is satisfied in the driving scene that is not determined to be in the sliding state, the lockup re-engagement is performed. Began to meet engine brake requirements.

Next, the effect will be described.
In the lockup clutch control device of the first embodiment, the effects listed below can be obtained.

(1) In a vehicle provided with a torque converter 4 having a lock-up clutch 3 between an engine 1 and a transmission (continuously variable transmission 6),
Lockup control means (FIG. 4) is provided for performing control to re-engage the lockup clutch 3 by increasing the fuel of the engine 1 when the lockup clutch 3 is released in a coasting state by releasing the accelerator pedal;
The lock-up control means (FIG. 4) has a sliding state determination unit (S6) that determines whether or not it is a sliding state that is traveling due to inertia, and if it is determined that the vehicle is in the sliding state, the lock-up clutch 3 re-engagement control is started (FIG. 7).
For this reason, at the time of lock-up re-engagement in the coasting state, lock-up re-engagement at an early timing can be realized.

(2) If it is determined that the lock-up control means (FIG. 4) is in a sliding state, the lock-up control means (FIG. 5) performs fuel increase control that increases the engine speed increase gradient as the sliding state increases.
For this reason, in addition to the effect of (1), it is possible to achieve early lock-up re-engagement without giving the driver a sense of incongruity.

(3) When the lockup control means (FIG. 4) determines that the elapsed time condition from the release of the lockup is satisfied (YES in S5), the lockup control means (FIG. 4) Re-engagement control is started.
For this reason, in addition to the effect of (1) or (2), when the elapsed time condition is satisfied in the traveling scene that is not determined to be in the sliding state, the lockup re-engagement is started and the engine brake request can be met.

  As mentioned above, although the lockup clutch control apparatus for a vehicle according to the present invention has been described based on the first embodiment, the specific configuration is not limited to the first embodiment, and in each claim of the claims Design changes and additions are allowed without departing from the gist of the invention.

  In the first embodiment, as the lock-up control means, when it is determined that the vehicle is in the sliding state, the fuel increase control is performed in which the increasing gradient of the engine speed is increased as the sliding state is stronger. However, the lock-up control means may be an example in which when it is determined that the vehicle is in the sliding state, the fuel increase control is performed based on a predetermined increase in the engine speed regardless of the sliding state.

  In the first embodiment, as an example of the lockup control means, two conditions of the elapsed time from the lockup release and the sliding state condition are used as the control start conditions for starting the re-engagement control of the lockup clutch 3. However, as the lock-up control means, only the sliding state condition may be used as a control start condition for starting the re-engagement control of the lock-up clutch, and other than the two conditions of the elapsed time condition and the sliding state condition, An example in which the above condition is added may be used.

  In the first embodiment, the lock-up clutch control device of the present invention is applied to an engine vehicle equipped with a continuously variable transmission. However, the lock-up clutch control device according to the present invention can be applied to a hybrid vehicle as long as the engine is mounted on a drive source, and a stepped automatic shift is performed as a transmission. A stepped transmission may be used. In short, it can be applied to any vehicle provided with a torque converter having a lock-up clutch between the engine and the transmission.

1 Engine 2 Engine output shaft 3 Lock-up clutch 4 Torque converter 5 Transmission input shaft 6 Continuously variable transmission (transmission)
7 Drive shaft 8 Drive wheel 11 Engine control unit (ECU)
12 CVT control unit (CVTCU)
13 CAN communication line 14 Engine speed sensor 15 Turbine speed sensor (= CVT input speed sensor)
16 CVT output speed sensor (= vehicle speed sensor)
17 Accelerator opening sensor 18 Secondary rotational speed sensor 19 Primary rotational speed sensor

Claims (3)

In a vehicle provided with a torque converter having a lock-up clutch between an engine and a transmission,
When the lock-up clutch is released in a coasting state by releasing the accelerator pedal, a lock-up control means is provided for performing control to re-engage the lock-up clutch with an increase in fuel of the engine,
The lockup control means includes a sliding state determination unit that determines whether or not the vehicle is in a sliding state that is traveling due to inertia, and when it is determined that the vehicle is in a sliding state, relocking control of the lockup clutch is performed. A vehicle lock-up clutch control device. In the vehicle lock-up clutch control device according to claim 1,
When it is determined that the lockup control means is in a sliding state, the lockup clutch control device for a vehicle is characterized in that fuel increase control is performed to increase the engine speed increase gradient as the sliding state is stronger. In the vehicle lock-up clutch control device according to claim 1 or 2,
The lock-up control means starts re-engagement control of the lock-up clutch when it is determined that an elapsed time condition from the release of the lock-up is satisfied, regardless of the determination result of the sliding state. Vehicle lock-up clutch control device.