JP2001116125A - Control device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a vehicular automatic transmission which prevents the rollover of a one-way clutch even if maximum torque is applied under a driving condition, without changing the capacity of the one-way clutch. SOLUTION: The control device includes: an engine load detecting means for detecting the engine load of the vehicle; a drive mode identifying means which determines whether or not a drive mode has been selected by a travel mode selecting means; an engine load comparing and determining means for determining whether or not the engine load detected by the engine load detecting means is above a predetermined value; a drive mode engagement means which engages a brake for a predetermined period when the engine load is determined to be above the predetermined value; and a drive mode releasing means which releases the brake after the predetermined period has elapsed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an automatic transmission for a vehicle, and more particularly to a shift control in a case where a high load is applied during driving.

[0002]

2. Description of the Related Art Conventionally, as a control device for an automatic transmission,
A technique described in Japanese Patent Application Laid-Open No. H10-30688 is known. FIG. 14 shows a skeleton diagram and a fastening table of an automatic transmission with five forward speeds and one reverse speed.

According to the skeleton diagram, three one-way clutches F1, F2 and F3 are connected in parallel to three
F3, which engages in the driving state of the first and second forward speeds and idles in the driven state.
The one-way clutch has a B4
A brake and a B3 brake arranged in parallel are provided. The B4 brake is engaged in the first to fifth forward speeds, and the outer race of the one-way clutch F3 in the first and second forward speeds is fixed to the case and the sun gear S2 is fixed. It is possible to rotate in the reverse direction.
The brake is engaged in a coast state at the time of first and second forward speeds, and the engine brake can be operated.

[0004]

By the way, in the drive mode such as when the D range is selected, the one-way clutch is idled with an emphasis on fuel efficiency, and the brake is released to deactivate the engine brake, thereby setting the two-range clutch or the like. In an overrun mode such as one range, it is a common practice to operate the engine brake by engaging the brake in a coast state so as to match the driver's will as much as possible. That is, the brake is set for generating the engine brake at the time of driving, and the action at the time of driving in the drive mode is not set.

However, in the drive state of the drive mode, only the one-way clutch is responsible for torque. Therefore, it is necessary to set the clutch capacity so that the one-way clutch does not roll over even when the maximum torque is applied in the drive state. There was a problem that the machine became large. In particular, since the one-way clutch F3 is engaged at a low speed where a large torque is applied, there is a problem that the transmission is further enlarged.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. In an automatic transmission for a vehicle, it is assumed that the maximum torque in a driving state is applied without changing the capacity of a one-way clutch. Another object of the present invention is to provide a control device for an automatic transmission in which a one-way clutch does not roll over.

[0007]

As a means for solving the above-mentioned problems, in the first aspect of the present invention, the clutch engages when driving from the engine side to the wheel side, and idles when driving from the wheel side to the engine side. A control device for an automatic transmission, comprising: a one-way clutch, which is arranged in parallel with the one-way clutch, and a brake that, when engaged, activates an engine brake at a predetermined gear position, wherein the traveling state of the vehicle is affected. Select between an overrun mode in which the engine brake is activated by applying the brake when driving, and a drive mode in which the engine brake is deactivated by releasing the brake even when the vehicle is in the driven state. An engine load detecting means for detecting an engine load of the vehicle, A drive mode determination unit that determines whether a drive mode is selected by the traveling mode selection unit, an engine load comparison determination unit that determines whether an engine load detected by the engine load detection unit is equal to or greater than a predetermined value, When the engine load is determined to be equal to or greater than a predetermined value, a drive mode engagement means for engaging the brake for a predetermined period, and a drive mode release means for releasing the engagement of the brake after the predetermined period has elapsed. It is characterized by having.

According to a second aspect of the present invention, in the control device for an automatic transmission according to the first aspect, the predetermined period is
It is a predetermined time from the start of the vehicle.

According to a third aspect of the present invention, in the control device for an automatic transmission according to the first or second aspect, the predetermined period is a period from the start of the vehicle until the throttle opening becomes equal to or less than the predetermined opening. It is a period or a period until the vehicle speed becomes equal to or higher than a predetermined position.

[0010]

The automatic transmission according to claim 1, wherein the one-way clutch engages when driving from the engine side to the wheel side and idles when driven from the wheel side to the engine side, and the one-way clutch. And a brake, which is arranged in parallel with each other and, when engaged, activates an engine brake at a predetermined gear position.

The control device for the automatic transmission is provided with running mode selecting means. When the running mode selecting means selects the overrun mode, the brake is engaged when the running state of the vehicle is driven. When the engine brake is operated and the drive mode is selected, the engine brake is deactivated by releasing the brake even when the running state of the vehicle is driven.

At this time, the engine load of the vehicle is detected by the engine load detecting means, the drive mode determining means determines whether or not the drive mode is selected by the traveling mode selecting means, and the engine load comparing and determining means is provided. It is determined whether the engine load detected by the engine load detecting means is equal to or greater than a predetermined value, and when the engine load is determined to be equal to or more than the predetermined value, the drive mode engagement means engages the brake for a predetermined period, In the drive mode release means, the engagement of the brake is released after the predetermined period has elapsed.

Therefore, even in the drive mode, when it is determined that a high load is applied to the one-way clutch, such as during acceleration or starting, the multiple disc brakes arranged in parallel to the one-way clutch are activated. To conclude.
As a result, the load applied to the one-way clutch can be shared, and roll-over can be prevented without setting the capacity of the one-way clutch large. Therefore, the durability can be improved without increasing the size of the transmission.

In the control device for an automatic transmission according to a second aspect, the predetermined period is a predetermined time from the start of the vehicle.

Therefore, the control can be simplified by applying the present control only at the time of high load such as when starting.

According to a third aspect of the present invention, the predetermined period is a period from the start of the vehicle until the throttle opening becomes equal to or less than a predetermined opening, or until the vehicle speed becomes equal to or more than a predetermined value. Is set to be the period.

Therefore, it is possible to more accurately read the driver's intention to accelerate, and it is possible to eliminate unnecessary control periods.

[0018]

FIG. 1 is an overall configuration diagram of a gear transmission for an automatic transmission according to an embodiment of the present invention.
FIG. 2 is a skeleton diagram showing a gear transmission for an automatic transmission according to the first embodiment. In FIGS. 1 and 2, G
1, G2, G3 are planetary gears, M1, M2 are connection members, C1, C2, C3 are clutches, B1, B2, B3,
B4 is a brake, F1, F2, and F3 are one-way clutches, IN is an input shaft (input member), and OUT is an output shaft (output member).

The first planetary gear G1 has a first sun gear S
1, a first ring gear R1, and a single pinion type planetary gear having a first carrier PC1 supporting a pinion meshing with both gears S1 and R1.

The second planetary gear G2 has a second sun gear S
2, a second ring gear R2, and a single pinion type planetary gear having a second carrier PC2 that supports a pinion that meshes with both gears S2 and R2.

The third planetary gear G3 has a third sun gear S
3, a third ring gear R3, and a single pinion type planetary gear having a third carrier PC3 that supports a pinion that meshes with both gears S3 and R3.

The first connecting member M1 is a first carrier.
A member that integrally connects the PC 1 and the third ring gear R3.

The second connecting member M2 is a member for integrally connecting the second ring gear R2 and the third carrier PC3.

The first clutch C1 is a clutch for selectively connecting and disconnecting the first ring gear R1 and the second ring gear R2.

The second clutch C2 includes a second sun gear S
The clutch selectively connects and disconnects the second sun gear S3 with the third sun gear S3. The second clutch C2 is provided with a first one-way clutch F1 in parallel.

The third clutch C3 is connected to a third carrier PC
3 and a clutch that selectively restrains the third sun gear S3.

The first brake B1 is a brake for selectively stopping the rotation of the second connecting member M2.

The second brake B2 is provided with a first sun gear S
This is a brake for selectively stopping one rotation. The second one-way clutch F is connected in parallel to the second brake B2.
2 are provided.

The third brake B3 is provided with a second sun gear S
This is a brake for selectively stopping the rotation of No. 2. The third brake B3 is connected in parallel with the fourth brake B4 and the third brake B4.
A one-way clutch F3 (B4 and F3 are arranged in series with each other) is provided.

The input shaft IN is connected to the first ring gear R1, and inputs the engine rotational driving force via a torque converter (not shown).

The output shaft OUT is connected to the second carrier PC2, and transmits the output rotational driving force to driving wheels via a final gear (not shown).

Each of the clutches C1, C2, C3 and the brakes B1, B2, B3, B4 is provided with an unillustrated transmission hydraulic control device (hydraulic control type, electronic control type) for generating an engagement pressure and a release pressure at each shift speed. , Hydraulic pressure + electronic control type) are connected.

[Shift operation] FIG. 3 is a diagram showing a fastening operation table in the automatic transmission gear transmission according to the first embodiment, and FIG. FIG. 4 is a diagram showing a torque transmission path of FIG.

In FIG. 3, △ indicates torque at power-on.
C is related to torque transmission during coasting.
The oil supply to the friction element, but the output
There is no effect, (○) is overrun mode
In the state to be concluded, (○)^*Is closed at the time of selection,
Release state except for overrun mode after ()
^**Indicates the state of fastening only under high load, ○ indicates the fastening state
You. Note that the overrun mode is a select mode (not shown).
Trevor's range position can be 2 range or 1 range
Or automatic shift mode and manual shift mode
Manual transmission mode is selected if the transmission is
Is generally called overrun mode.
You. In addition, the drive mode described later is a drive mode (not shown).
When the range position of the lect lever is set to D range
If the automatic transmission mode has an automatic transmission mode and a manual transmission mode,
Automatic transmission mode is selected if it is a transmission
The cases are collectively called drive mode.

4 is a torque transmission path at the first speed, FIG. 5 is a torque transmission path at the second speed, FIG. 6 is a torque transmission path at the third speed, and FIG. 7 is a torque transmission path at the fourth speed. 8 shows a torque transmission path at the fifth speed, and FIG. 9 shows a reverse torque transmission path.

FIG. 10 is a block diagram showing an electronic control system of an automatic transmission to which the control device of the embodiment is applied.

Various signals such as an idle switch signal 3, a full throttle signal 4, a throttle sensor signal 5, and an engine speed sensor signal 6 are input from the engine 1 to the A / T control unit 20. Further, an inhibitor switch signal 7, a temperature sensor signal 8, a vehicle speed sensor signal 9, and a turbine sensor signal 10 are input from the control unit of the automatic transmission 2 to the A / T control unit 20.

From the A / T control unit 20,
A control signal is sent to the ECCS control unit 30 and the control unit of the automatic transmission 2 receives C
1 solenoid 11, C2 solenoid 12, C3 solenoid 13, B1 solenoid 14, B2 solenoid 15, B
A control signal is output to each of the three solenoids 16 and the B4 solenoid 17. As described above, in the automatic transmission according to the present embodiment, the hydraulic pressure for each engagement element is supplied by an independent solenoid, so that control with a high degree of freedom can be performed. .

(Embodiment 1) FIG. 11 is a flowchart of the B3 brake engagement control under a high load according to Embodiment 1 of the present invention.

In step 101, the timer count value t is set to 0 when the vehicle starts.

In step 102, the operation mode, vehicle speed,
The gear position, throttle opening, and select position are read. In step 103, it is determined whether the drive mode or the overrun mode has been selected. If the overrun mode has been selected, this control is terminated. If the mode is selected, step 104
Proceed to. In step 104, it is determined whether or not the gear position is the first speed. If YES, the process proceeds to step 105, and if NO, the control ends.

In step 105, it is determined whether the vehicle speed is lower than a predetermined value.
Proceeding to 06, this control is terminated if NO. In step 106, it is determined whether or not the throttle opening is equal to or more than a predetermined value. If YES, the process proceeds to step 107, and if NO, the control is terminated. In step 107, the timer count value t is set to t + 1.

In step 108, the B3 brake is engaged. In step 109, it is determined whether or not the timer count value t is equal to or greater than a predetermined value. If YES, the process proceeds to step 110, and if NO, the process proceeds to step 107.

In step 110, the B3 brake is released. (Equivalent to the drive mode release means in the claims) That is, the timer count value t is set to 0 when the vehicle starts,
The operation mode, vehicle speed, gear position, throttle opening, and select position are read.

Next, it is determined whether the drive mode or the overrun mode is selected. If the drive mode is selected, it is determined whether the gear position is the first speed. This is because the maximum torque is applied during the acceleration of the first gear. Next, it is determined whether or not the vehicle speed is lower than a predetermined value, and it is determined whether or not the throttle opening is equal to or higher than a predetermined value, thereby determining that the engine load is high.

Next, the timer count value t is set to t + 1, and the B3 brake is engaged. Repeat this control,
When the timer count value t exceeds a predetermined value, the B3 brake is released. That is, when it is determined that the engine load is high, the B3 brake is engaged until the timer count value reaches the predetermined value. ( ^Indicated by (○) ^** in FIG. 3).
By engaging the three brakes, the one-way clutch F3
In addition, since the load on the B4 brake is reduced, the capacity can be set small, and the size and weight of the automatic transmission can be reduced. (Corresponding to claim 2) FIG. 12 is a diagram showing a torque transmission path when the B3 brake engagement control at the time of high load is executed according to the embodiment.
As shown in the figure, by applying the B3 brake, the torque applied to the second sun gear S2 is conventionally supported only by the B4 brake and the F3 one-way clutch as shown in FIG. By doing so, the load on the B4 brake and the one-way clutch F3 can be reduced.

As described above, in the automatic transmission according to the first embodiment, the one-way clutch F3 which is engaged when driving from the engine side to the wheel side and idles when driven from the wheel side to the engine side is provided with the one-way clutch F3. , One-way clutch F
And a B3 brake that is arranged in parallel with the engine 3 and that, when engaged, activates an engine brake at a predetermined gear.

The control device for the automatic transmission is provided with running mode selecting means. When the running mode selecting means selects the overrun mode, the multi-disc brake is engaged when the running state of the vehicle is driven. Thus, the engine brake is operated, and when the drive mode is selected, the engine brake is deactivated by releasing the multi-disc brake even when the running state of the vehicle is driven.

At this time, at step 102, the engine load of the vehicle is detected, and at step 103,
It is determined whether or not the drive mode is selected by the traveling mode selection means.
It is determined whether or not the engine load detected by the engine load detecting means is equal to or greater than a predetermined value. If it is determined in steps 104 to 106 that the engine load is equal to or greater than the predetermined value, in step 108, the multi-disc brake is activated. The engagement is performed for a predetermined period, and in step 110, after the predetermined period has elapsed, the engagement of the multiple disc brake is released.

Therefore, even if the drive mode is set, if it is determined that a high load is applied to the one-way clutch F3, such as during acceleration or starting, the B3 brake disposed in parallel with the one-way clutch F3 is determined. To conclude. This makes it possible to share the load applied to the one-way clutch F3, and to prevent rollover without setting the capacity of the one-way clutch F3 large. Therefore, the durability can be improved without increasing the size of the transmission.

In step 101, the timer count value is set to 0, in step 107, the timer count value is set to t + 1, and in step 109, the timer count value is set so that the predetermined period is set to a predetermined time from the start of the vehicle. Since the B3 brake is released when t becomes equal to or more than the predetermined value, the control can be simplified by applying the present control only at the time of high load such as starting.

(Embodiment 2) FIG. 13 is a flowchart of the B3 brake engagement control under a high load according to Embodiment 2 of the present invention.

In step 201, the operation mode, vehicle speed,
The gear position, throttle opening, and select position are read. In step 202, it is determined whether the drive mode or the overrun mode has been selected. If the overrun mode has been selected, this control is terminated. If the mode is selected, step 203
Proceed to. In step 203, it is determined whether the gear position is the first speed. If YES, the process proceeds to step 204, and if NO, the control is terminated.

In step 204, it is determined whether the vehicle speed is lower than a predetermined value.
Go to step 05, if NO, proceed to step 207. In step 205, it is determined whether or not the throttle opening is equal to or greater than a predetermined value. If YES, the process proceeds to step 206, and if NO, the process proceeds to step 207. (Corresponding to an engine load comparison determining means in the claims) In step 206, the B3 brake is engaged. In step 207, the B3 brake is released. That is, the drive mode, the vehicle speed, the gear position, the throttle opening, and the select position are read, and it is determined whether the drive mode or the overrun mode is selected. When the drive mode is selected, it is determined whether the gear position is the first speed. Next, when it is determined that the vehicle speed is lower than the predetermined value and the throttle opening is higher than the predetermined value, the B3 brake is engaged. At this time, the vehicle speed determination and the throttle opening degree determination are repeated.

When it is determined that the vehicle speed is higher than the predetermined value or the throttle opening is lower than the predetermined value, B
3 Brake is released.

That is, in the first embodiment, the engagement period of the B3 brake is determined by the timer count value t, whereas in the second embodiment, it is determined by the vehicle speed and the throttle opening. different. As described above, in the control device for an automatic transmission according to the second embodiment, the predetermined period is such that the throttle opening is equal to or less than the predetermined opening from the start of the vehicle in steps 204 to 206. Or a period until the vehicle speed becomes equal to or higher than a predetermined value.

Therefore, it is possible to more accurately read the driver's intention to accelerate, and unnecessary control periods can be eliminated.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an automatic transmission according to an embodiment.

FIG. 2 is a conceptual diagram of an automatic transmission according to an embodiment.

FIG. 3 is an engagement logic table of the automatic transmission according to the embodiment.

FIG. 4 is a diagram illustrating a torque transmission path during one shift of the automatic transmission according to the embodiment.

FIG. 5 is a diagram illustrating a torque transmission path during two shifts of the automatic transmission according to the embodiment.

FIG. 6 is a diagram illustrating a torque transmission path during three shifts of the automatic transmission according to the embodiment.

FIG. 7 is a diagram illustrating a torque transmission path at the time of four shifts of the automatic transmission according to the embodiment.

FIG. 8 is a diagram illustrating a torque transmission path at the time of five shifts of the automatic transmission according to the embodiment.

FIG. 9 is a diagram illustrating a torque transmission path during reverse movement of the automatic transmission according to the embodiment.

FIG. 10 is a block diagram of an electronic control system of the automatic transmission according to the embodiment.

FIG. 11 is a flowchart showing a B3 brake engagement control under a high load in the first embodiment.

FIG. 12 is a torque transmission path diagram at the time of high load B3 brake engagement control in the embodiment.

FIG. 13 is a flowchart showing B3 brake engagement control under a high load according to the second embodiment.

FIG. 14 shows a skeleton diagram and a fastening table of an automatic transmission showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 2 Automatic transmission 20 A / T control unit 30 ECCS control unit

Claims (3)

[Claims] A one-way clutch that is engaged when driving from the engine side to the wheel side and idles when driven from the wheel side to the engine side; A control device for an automatic transmission, comprising: a brake for activating an engine brake in the vehicle; and an overrun mode for activating the engine brake by applying the brake when the vehicle is in a driven state. In a control device including a driving mode selecting means for selecting a driving mode in which the engine brake is deactivated by releasing the brake even when the driving state is driven, the engine load detecting the engine load of the vehicle Whether the drive mode is selected by the detection means and the traveling mode selection means Drive mode determining means for determining; engine load comparing and determining means for determining whether the engine load detected by the engine load detecting means is equal to or greater than a predetermined value; and braking when the engine load is determined to be equal to or greater than a predetermined value. And a drive mode releasing means for releasing the engagement of the brake after the predetermined time period has elapsed. 2. The control device for an automatic transmission according to claim 1, wherein the predetermined period is a predetermined time from the start of the vehicle. 3. The control device for an automatic transmission according to claim 1, wherein the predetermined period is a period from the start of the vehicle until the throttle opening becomes equal to or less than the predetermined opening or the vehicle speed is at a predetermined position. A control device for an automatic transmission, which is a period until the above.