JP2013221590A - Control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent reduction in heat-resisting property of a lock-up latch when traveling a vehicle by slipping a lock-up clutch.SOLUTION: A control device is mounted in a vehicle that includes an engine 10, an automatic transmission 16 including a clutch C1 which disconnects the engine 10 and driving wheels, and a torque converter 14 which is provided between the engine 10 and the automatic transmission 16 and includes a lock-up clutch 26, and the control device controls the clutch C1 and the lock-up clutch 26. In the control device, when slipping the clutch C1 and the lock-up clutch 26 from a state where the clutch C1 and the lock-up clutch 26 are engaged, the clutch C1 is slipped and then, the lock-up clutch 26 is slipped.

Description

  The present invention relates to a vehicle control device including a fluid coupling provided with a lock-up clutch and an automatic transmission provided with a friction engagement device for power transmission.

A vehicle is known that includes a torque converter provided with a lock-up clutch and an automatic transmission provided with a friction engagement device for power transmission. And the content which slips a lockup clutch from the state which engages a lockup clutch and engages the forward clutch of a friction engagement device is disclosed by patent document 1. FIG.

JP 2004-263733 A

By the way, when the slip amount of the lockup clutch is increased, it becomes easy to suppress the vehicle shock, but the heat resistance of the lockup clutch is deteriorated due to frictional heat generated by the slip.

Here, Patent Document 1 discloses the content of sharing the slip amount by using the slip of the forward clutch and the slip of the lockup clutch, but at what timing the forward clutch and the lockup clutch are slipped. There is no description.

For example, if the forward clutch is slipped after the lockup clutch is slipped first, the rotational speed of the lockup clutch on the turbine side changes when the forward clutch is slipped. Therefore, it becomes difficult to perform slip control of the lockup clutch with high accuracy, and the heat resistance of the lockup clutch cannot be improved. The reason for this is that the slip control of the lock-up clutch is the control of the slip amount between the rotational speed on the pump side of the torque converter and the rotational speed on the turbine side of the torque converter. This is because it becomes difficult to control the slip amount. Also, the lock-up clutch has a larger diameter than the forward clutch and is inferior to the forward clutch in terms of responsiveness and controllability, so it is more difficult to control the slip amount when one of the controlled rotational speeds changes. It becomes.

The present invention has been made in view of the above circumstances, and an object thereof is a vehicle including a torque converter provided with a lock-up clutch and an automatic transmission provided with a forward clutch. An object of the present invention is to provide a vehicle control device that improves the heat resistance of a lockup clutch when the lockup clutch is slipped from a state in which the lockup clutch and the forward clutch are engaged.

In order to achieve this object, a control device according to a first aspect of the present invention is provided between an engine, an automatic transmission provided with a clutch for separating the engine and a drive wheel, and the engine and the automatic transmission. And a control device for controlling the clutch and the lockup clutch, wherein the clutch and the lockup clutch are engaged with each other. When the slip-up clutch is slipped, the lock-up clutch is slipped after the clutch is slipped.

A control device according to a second invention is the control device according to the first invention, wherein when the clutch and the lockup clutch are engaged from the state where the clutch and the lockup clutch are slipped, the lockup clutch is The clutch is engaged after being engaged.

A control device according to a third aspect of the present invention includes an engine, an automatic transmission provided with a clutch for separating the engine and the drive wheel, and a lockup clutch provided between the engine and the automatic transmission. A control device that is mounted on a vehicle having a torque converter and controls the clutch and the lock-up clutch, wherein the clutch and the lock-up clutch are engaged when the clutch and the lock-up clutch are slipped. In the case of combining, the clutch is engaged after the lock-up clutch is engaged.

  According to the first aspect, the change in the rotational speed of the lock-up clutch on the turbine side is suppressed, and the slip amount of the lock-up clutch can be easily controlled. Therefore, the slip control of the clutch and the lockup clutch can be executed with high accuracy, so that the heat resistance of the lockup clutch can be improved.

According to the second invention, when the clutch and the lockup clutch are returned to the engaged state, the change in the rotational speed of the lockup clutch on the turbine side is suppressed, and the slip amount of the lockup clutch can be easily controlled. Therefore, since the slip control of the lockup clutch when the lockup clutch is engaged in addition to the first invention can be executed with high accuracy, the heat resistance of the lockup clutch can be further improved.

  According to the third invention, the change in the rotational speed of the lockup clutch on the turbine side is suppressed, and the slip amount of the lockup clutch can be easily controlled. Therefore, according to the second invention, the slip control of the clutch and the lockup clutch can be executed with high accuracy, so that the heat resistance of the lockup clutch can be improved.

It is a figure explaining the principal part of the motor | power_engine and drive system of a vehicle to which the control apparatus which is one Example of this invention was applied. FIG. 2 is a skeleton diagram illustrating a configuration of the automatic transmission of FIG. 1. FIG. 3 is a diagram illustrating a gear stage achieved by a combination of operations of the plurality of hydraulic friction engagement devices in the automatic transmission shown in FIG. 2. It is a figure explaining the principal part structure of the hydraulic control circuit which controls the gear stage etc. of the automatic transmission shown in FIG. FIG. 2 is a functional block diagram illustrating a main part of a control function by an electronic control device provided in the vehicle of FIG. It is a flowchart explaining the principal part of the control action by the electronic controller of FIG. It is a flowchart explaining the principal part of the control action by the electronic controller of FIG. It is a time chart explaining the principal part of the control action by the electronic controller of FIG.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a diagram illustrating a configuration of a vehicle power transmission device to which a vehicle control device according to an embodiment of the present invention is applied. FIG. 2 is a skeleton diagram illustrating a configuration of the automatic transmission 16. . In the figure, the output of the engine 10 as a power source is input to the automatic transmission 16 via a torque converter 14 and transmitted to a pair of drive wheels via a differential gear device and an axle (not shown). Yes.

The torque converter 14 is directly connected between the pump impeller 20 connected to the engine 10, the turbine impeller 24 connected to the input shaft 22 of the automatic transmission 16, and the pump impeller 20 and the turbine impeller 24. And a stator impeller 30 that is prevented from rotating in one direction by a one-way clutch 28. The lock-up clutch 26 is provided in the turbine impeller 24 for absorbing vibration, and has a damper (buffer device) 26a having a sufficiently larger diameter than the friction engagement device in the automatic transmission 16 and the input shaft 22. The relative rotation angle range with respect to the input shaft 22 is limited by being connected to the damper 26a, and the friction plate 26b is annularly formed on the outer peripheral portion. This is a large-diameter single-plate clutch provided with a disc-shaped clutch piston 26c.

The automatic transmission 16 includes a first transmission 32 that switches between two stages of high and low, and a second transmission 34 that can switch between a reverse gear and four forward gears. The first transmission 32 is supported by the sun gear S0, the ring gear R0, and the carrier K0 so as to be rotatable, and the planetary gear P36 includes a planetary gear P0 meshed with the sun gear S0 and the ring gear R0, and the sun gear S0 and the carrier. A clutch C0 and a one-way clutch F0 provided between K0 and a brake B0 provided between the sun gear S0 and the housing 38 are provided.

  The second transmission 34 is supported by the sun gear S1, the ring gear R1, and the carrier K1, and the first planetary gear device 40 including the planetary gear P1 that is meshed with the sun gear S1 and the ring gear R1, and the sun gear S2. A second planetary gear unit 42 including a planetary gear P2 that is rotatably supported by the ring gear R2 and the carrier K2 and meshed with the sun gear S2 and the ring gear R2, and the sun gear S3, the ring gear R3, and the carrier K3 is rotatable. And a third planetary gear unit 44 comprising a planetary gear P3 supported and meshed with the sun gear S3 and the ring gear R3.

  The sun gear S1 and the sun gear S2 are integrally connected to each other, the ring gear R1, the carrier K2, and the carrier K3 are integrally connected, and the carrier K3 is connected to the output shaft 46. Further, the ring gear R2 is integrally connected to the sun gear S3 and the intermediate shaft 48. A clutch C1 is provided between the ring gear R0 and the intermediate shaft 48, and a clutch C2 is provided between the sun gear S1, the sun gear S2, and the ring gear R0. A band-type brake B1 for stopping the rotation of the sun gear S1 and the sun gear S2 is provided in the housing 38. A one-way clutch F1 and a brake B2 are provided in series between the sun gear S1 and sun gear S2 and the housing 38. The one-way clutch F <b> 1 is configured to be engaged when the sun gear S <b> 1 and the sun gear S <b> 2 try to reversely rotate in the direction opposite to the input shaft 22.

  A brake B3 is provided between the carrier K1 and the housing 38, and a brake B4 and a one-way clutch F2 are provided in parallel between the ring gear R3 and the housing 38. The one-way clutch F2 is configured to be engaged when the ring gear R3 attempts to rotate in the reverse direction.

  In the automatic transmission 16 configured as described above, for example, according to the operation table shown in FIG. 3, the reverse gear and the forward gear ratio of the first to fifth gears in which the gear ratio γ sequentially decreases. It is switched to any gear. In FIG. 3, “◯” represents the engaged state, the blank represents the released state, “◎” represents the engaged state during engine braking, and “Δ” represents the engagement not involved in power transmission. .

  As is apparent from FIG. 3, the clutch C <b> 0 and the clutch C <b> 1 are engaged at the first speed gear stage used when starting the vehicle. The clutch C0 is engaged in order to integrally rotate the rotating elements of the HL planetary gear unit 36 constituting the first transmission 32, and the clutch C1 is an HL planetary gear unit that is a power transmission path in the automatic transmission 16. 36 is arranged in series between the ring gear R0 and the intermediate shaft 48, and is engaged for power transmission. The clutch C1 is composed of a wet multi-plate type clutch having a plurality of mutually stacked friction plates that are always lubricated by hydraulic oil and frictionally engaged for power transmission.

FIG. 4 is a diagram for explaining a main part of the hydraulic control circuit 56 for controlling the operation of the lockup clutch 26 and the automatic transmission 16 of the torque converter 14. In FIG. 4, a mechanical oil pump 60 that is mechanically connected to the engine 10 and directly driven by the rotation is sucked through the strainer 64 through the working oil that has returned to the oil pan 62 that functions as an oil tank. The pressure is fed to the relief type first pressure regulating valve 66. The first pressure regulating valve 66 has a first line pressure so as to have a magnitude corresponding to the input torque of the automatic transmission 16 in accordance with a throttle opening hydraulic pressure signal from a linear solenoid valve SLT that operates according to a command from the electronic control unit 90. Regulate PL1. Since the line hydraulic pressure PL1 is a hydraulic pressure source of the hydraulic friction engagement device such as the first clutch C1, the second clutch C2, etc., the line hydraulic pressure PL1 is as low as possible within a range in which the hydraulic friction engagement device does not slip. Pressure is adjusted. The second pressure regulating valve 68 regulates the second line pressure using the hydraulic oil relief from the first pressure regulating valve 66 as a base pressure. The lock-up control valve 70 uses the second line pressure PL2 as a source pressure, and outputs a hydraulic pressure for putting the lock-up clutch 26 into an engaged state, a released state, and a slip state in accordance with a command from the electronic control unit 90.

The manual valve 72 to which the line hydraulic pressure PL1 is supplied is mechanically connected to a shift operation lever 73 that functions as a shift operation device, thereby operating positions thereof such as P position, R position, N position, D position, and S position. The switching position is changed in conjunction with the L position, and the line hydraulic pressure PL1 is output from the port corresponding to the switching position. When the shift operation lever 73 is operated to the forward travel position (range), that is, the D position, the S position, and the L position, the line hydraulic pressure PL1 is output toward the first clutch C1, the second clutch C2, and the like. During forward travel, the second clutch C2 is connected to the manual valve 72 via a shift valve (not shown) so that the line hydraulic pressure PL1 is supplied to the second clutch C2 at the fourth speed and the fifth speed. In addition, an oil passage is provided between the first clutch C1 and the manual valve 72 to start more quickly when the engine 10 is automatically returned from the stopped state or when the N → D shift starts. That is, at the time of first apply (rapid supply), the line oil pressure PL1 is supplied from the manual valve 72 to the first clutch C1 via the switching valve 78 controlled to open and close by the large orifice 74 and the electromagnetic valve 76. At first apply (normal supply), the line oil pressure PL1 is supplied from the manual valve 72 to the first clutch C1 via the large orifice 74 and the small orifice 80. The check valve 82 provided in parallel with the small orifice 80 is closed when the line oil pressure PL1 is supplied to the first clutch C1, but is opened when the hydraulic oil is discharged from the first clutch C1, The first clutch C1 is quickly released. The C1 accumulator 84 connected to the first clutch C1 and the orifice 86 provided in the connection path are for smoothly engaging the first clutch C1 at the time of normal N → D shift or starting. is there.

FIG. 5 is a functional block diagram illustrating a main part of a control function by the electronic control unit 90 provided in the vehicle of FIG. 1, that is, a slip control function of the clutch and the lockup clutch. The electronic control unit 90 includes a so-called microcomputer including a CPU, a ROM, a RAM, an input / output interface, and the like, and performs signal processing according to a program stored in advance in the ROM while using a temporary storage function of the RAM. I do. The electronic control unit 90 is a signal for controlling a shift solenoid that drives a shift valve in the hydraulic control circuit 56 in order to switch the gear stage of the automatic transmission 16, and in the hydraulic control circuit 56 in order to control the opening and closing of the lockup clutch 26. A signal for controlling the lockup control valve 70, a signal for controlling the linear solenoid valve SLT for regulating the line pressure, and the like are output to execute control of the hydraulic control circuit 56 and the like.

In the electronic control unit 90, a signal representing the accelerator opening degree ACC corresponding to the depression amount of the accelerator pedal of the user, a signal representing the vehicle speed V corresponding to the rotational speed NOUT of the output shaft 46, and the like from each sensor shown in FIG. Supplied respectively.

  The slip control determination unit 96 of the electronic control device 90 determines, for example, whether or not the lockup clutch 26 is to be slipped when acceleration of the vehicle is required during traveling based on the accelerator opening ACC and the vehicle speed V. Then, a signal instructing the slip amount is output to the clutch control unit 100 and the lockup clutch control unit 98. The lockup clutch control unit 98 outputs a signal for instructing the engagement pressure of the lockup clutch 26 to the hydraulic control circuit 56 according to the slip amount received from the slip control determination unit 96. The clutch control unit 100 outputs a signal for commanding the engagement pressure of the clutch C1 to the hydraulic control circuit 56 in accordance with the slip amount received from the slip control determination unit 96.

  FIG. 6 is a flowchart for explaining a main part of the control operation by the electronic control unit 90 of FIG. 5, and is repeatedly executed at a predetermined cycle of about several milliseconds to tens of milliseconds.

  The flowchart of FIG. 6 is executed when the clutch C1 and the lockup clutch 26 are engaged. First, in step (hereinafter, step is omitted) S1, it is determined whether or not the slip of the lockup clutch 26 is requested. If the determination in S1 is negative, this routine is terminated. If the determination is affirmative, slipping of the clutch C1 is started in S2.

Next, in S3, it is determined whether or not the clutch C1 is in a slip state. When this S3 is denied, determination of S3 is repeated until the clutch C1 will be in a slip state. On the other hand, if the determination in S3 is affirmative, the process proceeds to S4 to start slipping of the lockup clutch 26 and terminate this routine. The slip detection of the clutch C1 is detected, for example, when a slip command signal is output from the clutch control unit 100 and the clutch control unit 96 to the hydraulic control circuit 56, or when a predetermined time has elapsed since the output. Thus, the slip can be determined. Further, the theoretical value of the output rotational speed of the automatic transmission 16 obtained by multiplying the input rotational speed of the automatic transmission 16 that is the rotational speed of the input side of the clutch C1 by the speed ratio, and the automatic transmission detected by the vehicle speed sensor 94. The slip of the clutch C1 can also be determined by comparing the actual output rotational speed of the machine 16.

  FIG. 7 is a flowchart for explaining a main part of the control operation by the electronic control unit 90 of FIG. 5, and is repeatedly executed at a predetermined cycle of about several milliseconds to tens of milliseconds.

  The flowchart of FIG. 7 is executed when the clutch C1 and the lockup clutch 26 are slipped. First, in S5, it is determined whether or not the engagement of the lockup clutch 26 is requested. If the determination in S5 is negative, the routine is terminated. If the determination is affirmative, engagement of the lockup clutch 26 is started in S6.

Next, in S7, it is determined whether or not the lockup clutch 26 is in an engaged state. When this S7 is denied, the determination of S7 is repeated until the lockup clutch 26 is engaged. On the other hand, if the determination in S7 is affirmative, the process proceeds to S8 to start the engagement of the clutch C1 and end this routine. The determination of the engagement of the lock-up clutch 26 is made, for example, after an engagement command signal is output from the clutch control unit 100 and the lock-up clutch control unit 98 to the hydraulic control circuit 56 or after it is output. Engagement can be determined by detecting that a predetermined time has elapsed. Further, the engine speed NE, which is the rotational speed on the pump side of the lockup clutch 26, is compared with the rotational speed of the input rotational speed of the automatic transmission 16, which is the rotational speed on the turbine side, of the lockup clutch 26. Can also be determined.

FIG. 8 is a time chart for explaining a main part of the control operation by the electronic control unit 90 of FIG.

  First, at time t0 in FIG. 8, the vehicle is running with the clutch C1 and the lock-up clutch 26 engaged, which corresponds to the case where S1 in the flowchart in FIG. 6 is denied.

  Next, at time t1, for example, when the accelerator pedal is depressed and the accelerator opening ACC increases due to a user's acceleration request, slip of the lockup clutch is required. Then, slip of the clutch C1 is started.

  When the clutch C1 enters the slip state, the lockup clutch 26 starts to slip at time t2, and the clutch C1 and the lockup clutch 26 slip to travel. At time t3 when the accelerator opening degree ACC is decreased and the engagement of the lockup clutch 26 is required, that is, when the end of the slip is required, the engagement of the lockup clutch 26 is started. Next, when the lockup clutch 26 is engaged, the clutch C1 is engaged at time t4.

  Thus, by slipping the clutch C1 after slipping the clutch C1, changes in the rotational speed of the lockup clutch 26 on the turbine side are suppressed, and the slip amount of the lockup clutch 26 is easily controlled. Therefore, the slip control of the clutch C1 and the lockup clutch 26 can be executed with high accuracy, and the heat resistance of the lockup clutch 26 can be improved.

  As mentioned above, although one Example of this invention was described in detail with reference to drawings, this invention is not limited to this Example, It can implement in another aspect.

For example, when releasing the lockup clutch 26 from the state in which the clutch C1 and the lockup clutch 26 are engaged, the clutch C1 is slipped first, and the lockup clutch 26 is released with the clutch C1 slipped. Also good. By doing so, a change in the rotational speed of the lock-up clutch 26 on the turbine side is suppressed, and the slip amount of the lock-up clutch 26 can be easily controlled.

10: Engine 14: Torque converter 16: Automatic transmission 26: Lock-up clutch C1: Clutch 56: Hydraulic control circuit

Claims (3)

Mounted on a vehicle having an engine, an automatic transmission provided with a clutch for separating the engine and drive wheels, and a torque converter provided between the engine and the automatic transmission and provided with a lock-up clutch; A control device for controlling the clutch and the lock-up clutch,
When the clutch and the lockup clutch are slipped from a state in which the clutch and the lockup clutch are engaged, the control apparatus is configured to slip the lockup clutch after the clutch is slipped. When the clutch and the lockup clutch are engaged from a state where the clutch and the lockup clutch are slipped, the clutch is engaged after the lockup clutch is engaged. The control device according to claim 1. Mounted on a vehicle having an engine, an automatic transmission provided with a clutch for separating the engine and drive wheels, and a torque converter provided between the engine and the automatic transmission and provided with a lock-up clutch; A control device for controlling the clutch and the lock-up clutch,
When the clutch and the lockup clutch are engaged from a state in which the clutch and the lockup clutch are slipped, the lockup clutch is engaged and then the clutch is engaged. apparatus.