JP2002071004A - Control device for automatic transmission gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for an automatic transmission gear capable of enhancing driving performance and preventing performance of a friction member from deteriorating by prohibiting automatic control in such a slope or loading case that a vehicle recedes or the friction member is damaged. SOLUTION: In order to solve above subject, the friction member is prohibited or the friction member is sustained to a slipped state by means of a slope detection means detecting the slope and a loading detection means detecting the loading if the slope or the loading is more than some constant value. Furthermore, a throttle is sustained to a fully closed state until the friction member is finished to fasten regardless of a signal of the detection means for an accelerator pedal opening degree, in the case where the disengagement of the release of the friction member is decided during the release of the friction member.

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 control device which is not directly connected to an accelerator pedal and is controlled by an opening signal detected by accelerator pedal opening detecting means. A neutral control that includes a throttle control device for the internal combustion engine and releases or slides the friction member if a predetermined condition is satisfied even when the shift range is set to the forward travel range, and controls the friction member to a neutral state or near a neutral state. The present invention relates to a control device for an automatic transmission.

[0002]

2. Description of the Related Art In a conventional automatic transmission for a vehicle, when a shift range is set to a forward traveling range, it is necessary to drag a torque converter when the vehicle is stopped, and the load on an internal combustion engine increases with this. There was a problem that the fuel consumption rate deteriorated.

In order to solve this problem, when the shift range is set to the forward drive range and the vehicle is in a stopped state, the vehicle is started to the driver by detecting that the throttle opening is fully closed, the brake switch is ON, and the like. When it is determined that there is no intention, a technique is known in which the friction member is released or slipped, and the friction member is controlled to a neutral state or near a neutral state to improve the fuel consumption rate.

On the other hand, in an automatic transmission which performs hill hold control simultaneously with neutral control, a forward clutch is released when a predetermined condition is satisfied in order to prevent creep on a slope.
No. 263921.

[0005]

However, in the prior art, when the friction member is fastened and advanced from the neutral control state in which the friction member is released on a slope,
There is a possibility that the vehicle will be retracted due to the delay of the fastening, and the time until the fastening will be long, the temperature of the friction member will rise significantly,
There is a risk that performance will be degraded.

[0006] Similarly, in a vehicle having a large amount of load, the time required for fastening is long, the temperature of the friction member is significantly increased, and the performance may be degraded.

When the neutral control is released by depressing the accelerator from the neutral control state in which the friction member is released, the torque input to the transmission increases, the friction member slips, and the engine speed increases. . Further, the temperature of the friction member may be significantly increased, which may cause deterioration of performance and damage.

[0008] An object of the present invention is to provide a vehicle as running conditions.
For example, in the case of a gradient or a load amount that causes the vehicle to retreat or damage the friction member, automatic control is prohibited to improve the drivability and prevent the friction member from deteriorating in performance. Machine control device.

[0009] An object of the present invention is to provide a vehicle as running conditions.
If the friction member is not completely engaged when neutral control is released, control the automatic transmission to prevent the engine speed from rising up and reduce the shock when the friction member is engaged by maintaining the throttle fully closed. It is to provide a device.

[0010]

According to the present invention, there is provided an automatic transmission control apparatus comprising a vehicle state detecting means for detecting a running condition of a vehicle, wherein the neutral control means comprises: If the value indicating the traveling condition of the vehicle detected by the detection means is equal to or more than a certain value, the release of the friction member is prohibited or restricted even if the predetermined condition is satisfied.

Another feature of the present invention is that the vehicle state detecting means includes a gradient detecting means for detecting a gradient, and the detecting means inhibits release of the friction member if the gradient is equal to or more than a certain value. And maintaining the friction member in a slip state.

Another feature of the present invention is that the vehicle state detecting means includes a load amount detecting means for detecting a load amount, and if the load amount is equal to or more than a predetermined value,
The object of the present invention is to inhibit the release of the friction member or to keep the friction member in a slip state.

Another feature of the present invention is that the vehicle state detecting means includes a gradient detecting means for detecting a gradient, and a loading amount detecting means for detecting a loading amount. The object of the present invention is to inhibit the release of the friction member or keep the friction member in a slip state by a combination of the amounts.

Another feature of the present invention is that when it is determined that the release of the friction member is released during the release of the friction member, regardless of the signal of the accelerator pedal opening detection means, the throttle is operated until the engagement of the friction member is completed. The purpose is to maintain the fully closed state.

According to the present invention, the traveling conditions of the vehicle include:
For example, when the vehicle moves backward or has a gradient or load that may damage the friction member, the control device of the automatic transmission prohibits the automatic control, thereby improving the drivability.
In addition, it is possible to prevent performance degradation of the friction member.

If the frictional member is not completely closed when the neutral control is released as the running conditions of the vehicle, the throttle is kept fully closed to prevent the engine speed from rising and the frictional member to be fastened. The shock at the time can be reduced.

[0017]

Embodiments of the present invention will be described below.
FIG. 1 is a system configuration diagram including a control device for an automatic transmission according to an embodiment of the present invention. 1 is an engine, 2 is an automatic transmission (hereinafter abbreviated as AT), 3 is a propeller shaft, 4 is a differential device also serving as a final reduction gear, 5 is a drive wheel, 6 is an AT hydraulic circuit, and 7 is a microcomputer built-in. It is an electronic control unit (control unit) of the AT, that is, a control unit of an automatic transmission, and is referred to as an ATCU here. Reference numeral 8 denotes an electronic control unit (control unit) for the engine built in the microcomputer, which is herein referred to as an ECU. 9 is an air cleaner, 10 is an air flow sensor, 12 is a suction manifold, and 13 is an injector for injecting fuel. Reference numeral 11 denotes a throttle controller with a DC servo, which is not directly connected to the accelerator,
3 (drive-by-wire).

The inside of the AT further includes a torque converter 14.
And a gear train 15, which are provided with a turbine rotation sensor 16 for detecting the turbine speed and a vehicle speed sensor 17 for detecting the AT output shaft speed. ECU
8, sensor information such as a crank angle sensor, an air flow sensor 10, a throttle sensor 18, an engine cooling water temperature sensor (not shown), a sensor for detecting oxygen concentration of exhaust gas in an engine exhaust pipe, and an exhaust temperature sensor are input. Then, various calculations such as the engine speed are executed to output a valve opening drive signal to the injector 13 to control the amount of fuel, and a valve opening drive signal to the idle speed control valve (ISC) 19 to output the auxiliary air amount. Various controls, such as controlling the ignition timing by outputting an ignition signal to a spark plug (not shown), are performed.

FIG. 2 shows a control unit ATCU7 for an automatic transmission.
2 shows the functional blocks of FIG. The ATCU 7 includes a sensor input processing unit 71, a gradient estimating unit 72, and an automatic neutral control unit 7.
3. An automatic neutral prohibiting means 74 and a forward clutch control means 75 are provided. The ATCU 7 includes a turbine rotation sensor 16, a vehicle speed sensor 17, an ATF (AT
Oil) Temperature sensor and other sensor information, and signals from the ECU 8 such as the engine speed and throttle opening are input to the gradient estimating unit 72 and the automatic neutral control unit 73 via the sensor input processing unit 71. Sent.
The gradient estimating unit 72, the automatic neutral control unit 73, and the automatic neutral prohibiting unit 74 execute various calculations, and the forward clutch control unit 75 generates a control signal for the forward clutch 54. FIG. 4 shows the processing of the gradient estimating unit 72 and the automatic neutral inhibition means 74, and FIG. 5 shows the processing of the forward clutch control means 75.

The signal generated by the forward clutch control means 75 is output to the hydraulic control solenoid valve 20 mounted on the hydraulic circuit 6 as a valve opening drive signal to control the forward clutch 54.

In this embodiment, the method of directly detecting the amount of intake air of the engine by the air flow sensor 10 has been described. However, the present invention is not limited to this. For example, a calculation is performed based on the pressure in the intake manifold 12 and the intake air temperature. It goes without saying that a method of calculating the amount of air based on the engine speed, a method of calculating the amount of air by calculation from the throttle opening and the engine speed, or the like may be used. In this embodiment, the ATCU
And the ECU are separately provided, but the present invention is not limited to this, and the ATCU and the ECU may be integrated. Further, in the present embodiment, a configuration example of the front engine and the rear drive system is shown, but the present invention is not limited to this, and the front engine, the front drive system, the rear engine, the rear drive system,
It goes without saying that any system such as a four-wheel drive system may be used. In the present embodiment, the configuration example using the planetary gears is described, but the present invention is not limited to this, and the CVT method,
It goes without saying that a motor generator method may be used.

Next, the gear configuration of the AT2 will be described with reference to FIG. FIG. 3 is a skeleton diagram of the automatic transmission. This figure shows the most basic gear configuration for realizing the first to fourth forward speeds. The components are two sets of planetary gears, four clutches, two brakes, and two one-way clutches. Each of the two sets of planetary gears uses a single pinion gear, and has a structure in which a ring gear in the front row and a planet carrier in the rear row are integrated. The input is the rear sun gear, and the output is the same rear planet carrier.

First, in the first speed state, the forward clutch 5
When 4 is engaged, the forward one-way clutch 55 and the low one-way clutch 60 are fixed. Since these three act, the rear ring gear is fixed, and the driving force is transmitted from the rear sun gear to the rear planet gear, and is taken out from the output shaft 52.

The second speed shifts from the first speed to the band brake 5
3 is engaged to change the speed. The low one-way clutch 60 is automatically released only by the engagement of the band brake 53.

In the third speed, the band brake 5
3 is released and the high clutch 58 is simultaneously engaged. In the fourth speed, which is a shift change between friction elements that does not use a one-way clutch, the speed is changed by engaging the band brake 53 from the third speed. Further, the forward one-way clutch 55 is automatically released only by engaging the band brake.

In reverse, the reverse clutch 57 and the low & reverse brake 56 are engaged.

In these states, the friction member is controlled by a hydraulic control solenoid valve 20 provided in the hydraulic circuit 6 in response to a command from the ATCU 7. Alternatively, it is realized by directly controlling the friction member by the hydraulic control solenoid valve 20.

Next, the outline of the operation of the control device will be described with reference to FIG. FIG. 4 is a chart showing a control flow of the automatic transmission control device of the present invention. Block 101
As shown in (1), the gradient and the loading amount are always calculated by the vehicle gradient detecting means or the loading amount detecting means indicated by the block 102 from the vehicle data stored in the ATCU 7 and the vehicle state data calculated by the ECU 8.

When the vehicle stops, information on the driver's intention to stop is transmitted to the block 104 by means of the driver's intention to stop shown in block 103, and the neutral control determining means determines whether control is started or prohibited.

When it is determined that the control has started, block 102 is executed.
Is determined by the neutral control start determining means based on the gradient and the loading amount shown in block 105 to be a gradient or a loading amount at which the vehicle moves backward or damages the friction member. If so, the control is prohibited, or the friction member is held in a slip state by the friction member slip control means shown in block 106. Otherwise, neutral control is started.

When it is determined that the neutral control is started, the friction member is released by the neutral control means indicated by a block 107, and the neutral state is set.

During the neutral control, information on the driver's intention to start is transmitted to the neutral release determining means shown in block 109 by the driver's intention to recognize start shown in block 108. When the neutral release determining means determines that the control has been released, the routine proceeds to friction member fastening means shown in block 110.

Next, when it is determined by the friction member fastening completion determining means shown in block 111 that the fastening has not been completed, as shown in block 112, the throttle fully closed holding means controls the throttle control device. Outputs a signal to keep the throttle fully closed. Thereafter, the flow returns to the friction member fastening means shown in block 110, and this closed loop is maintained until the fastening of the friction member is completed.

When the fastening is completed, the throttle operation permitting means shown in block 113 outputs a signal for permitting the operation to the device for controlling the throttle.

A detailed embodiment of the present invention will be described below with reference to FIGS.
Description will be made using 0. Referring to FIG. 5, the vehicle gradient detecting means and the load amount detecting means shown in block 102 of the flowchart of FIG. 4 will be described.

First, the vehicle gradient detecting means will be described. The gradient resistance torque Tθ is obtained by the equation (1) from the balance of each torque element shown in FIG.

Tθ = T _D − (T _RL + Tα) (1) where, T _D : drive torque T _RL : running resistance torque Tα: acceleration Indicates resistance torque.

The driving torque T _D is obtained by the equation (2).

T _D = T _e × τ × G _r × G _f (2) where T _e : engine torque τ: torque ratio of torque converter G _r : transmission gear ratio G _f : Final gear ratio The flat ground running resistance torque T _RL is obtained by equation (3).

[0040] _{T RL = (λ × S ×} V SP 2 + μ r × W) × R T ········· (3) where, λ: air resistance coefficient S: before shadow projected area of the vehicle V _SP: vehicle speed mu _r: rolling resistance coefficient W: vehicle weight R _T: drive tire's dynamic radius driving torque Tα is obtained by (4).

Tα = (W + ΔW) × α / g × _RT (4) where α: vehicle acceleration g: gravitational acceleration ΔW: weight equivalent to rotary inertia The relationship between θ and the gradient resistance torque Tθ can be determined by equation (5).

Θ = sin ⁻¹ (Tθ / (W × g × R _T ) (5) Therefore, the constant determined by the vehicle by the equations (1) to (5) When the values of (the values that do not depend on traveling) are summarized, the gradient θ is
It can be obtained by equation (6).

[0043] _{θ = k 1 × T e ×} τ × G r -k 2 × V SP 2 -k 3 × α-k 4 ········· (6) (k 1 ~k 4 is a constant Next, the load amount detecting means will be described. From the gradient detecting means, comes to convert the equation to extract the payload W _d and (7).

Θ = (k_Five× T_e× τ × G_r-K₆× V_SP ^Two) / (W + W_d) -K_Three× α-k_Four ・ ・ ・ ・ ・ ・ (7) (k_Three~ K₆Is a constant) Engine torque T_e, The torque ratio τ of the torque converter,
Transmission gear ratio G_r, Vehicle speed V _SP(8)
And (9)₁= (K_Five× T_e1× τ₁× G_r1-K₆× V_SP1 ^Two) / (W + W_d) -K_Three× α₁-K_Four ・ ・ ・ ・ ・ ・ (8) θ_Two= (K_Five× T_e2× τ_Two× G_r2-K₆× V_SP2 ^Two) / (W + W_d) -K_Three× α_Two-K_Four ・ ・ ・ ・ ・ ・ (9) Same slope road (θ₁= Θ_Two), The equations (8) and (9)
Solving the equation gives the load capacity W _dCan be calculated.

W _d = ((k ₅ × (T _e1 × τ ₁ × G _r1 -T _e2 × τ ₂ × G _r2 ) −k ₆ × (V _SP1 ² −V _SP2 ² )) / (k ₃ × ( α ₂ −α ₁ ))-W (10) Referring to FIG. 6, the means for recognizing the driver's intention to stop the vehicle shown in block 103 of the flowchart in FIG. explain.

As means for recognizing the driver's intention to stop, (1) D range, 3 range, 2 range, or 1 range is set. (2) Idle SW is turned on or throttle opening is fully closed. (3) Vehicle speed = 0 km / h ( 4) Foot brake SW ON or parking brake SW ON If conditions (1) to (4) continue for a certain period of time, block 1
The neutral control start determining means shown in FIG. 04 determines that the driver has no intention to start, and permits the neutral control to be started.

Next, the neutral control judging means based on the gradient and the loading amount shown in the block 105 will be described. If any of the following conditions is satisfied based on the gradient and the loading amount immediately before the stop calculated in block 102, the neutral control is prohibited or the process shifts to friction member slip control shown in block 106.

Condition 1 gradient> threshold Condition 2 loading amount> threshold Condition 3 condition obtained by combination of gradient and loading amount =
Prohibition FIG. 7 is a diagram showing an example of the relationship between the control pattern, that is, the gradient θ, the load W, and the control area. The area where the gradient θ is larger than the predetermined range, the area where the loading amount W is larger than the predetermined range, and the area outside the above-mentioned area but the gradient θ
A region where both the load and the load amount W are relatively large is a region where control is prohibited or the friction member is held in a slip state.

Next, the friction member slip control means shown in block 106 will be described with reference to FIG. As indicated by a block 131, a target turbine speed is determined. When the target turbine speed is determined, an initial hydraulic command value to the forward clutch (friction member) 54 corresponding to the target turbine speed is output as indicated by a block 132,
Speed up the convergence of feedback by the target turbine speed.

Next, the actual turbine speed is detected as shown in block 133. If the actual turbine speed is lower than the target turbine speed lower limit value as shown in block 134, the process proceeds to block 135. Next, a certain oil pressure is reduced from the current oil pressure command value of the forward clutch 54.

Next, if the actual turbine speed is higher than the target turbine speed upper limit value as indicated by a block 136, a certain hydraulic pressure is obtained from the current hydraulic command value of the forward clutch 54 as indicated by a block 137. To rise.

Otherwise, as shown by block 138, the hydraulic command value of the forward clutch is held as it is,
Feedback control is performed on the turbine rotation speed to a certain rotation width.

On the other hand, if the neutral control judging means based on the gradient and the loading amount shown in block 105 determines that the neutral control is started, the forward clutch 54 is released by the neutral control means shown in block 107.
Maintain the automatic transmission in neutral.

Next, the means for recognizing the driver's intention to start at block 108 in the flowchart of FIG. 4 and the means for determining neutral control cancellation at block 109 will be described with reference to FIG.

As means for recognizing the driver's intention to start, (1) accelerator opening> threshold (2) vehicle speed> 0 km / h (3) foot brake SW OFF or parking brake SW OFF (1) to (3) If any of the conditions is satisfied, block 109
In the neutral control release determination means shown in (1), it is determined that the driver has an intention to start, and the flow shifts to friction member fastening means shown in block 110.

Next, referring to FIG. 10, the friction member fastening means shown in block 110 of the flowchart of FIG.
Throttle fully closed holding means and block 113 shown in FIG.
The throttle operation permission means shown in FIG.

If the driver steps on the accelerator during the neutral control, the condition "(1) accelerator opening>threshold" in the neutral control recognizing means in block 108 is satisfied, and the neutral control shown in block 109 In the cancellation determining means, the neutral control cancellation is determined.

When it is determined that control is released, block 11 is executed.
The engagement hydraulic pressure command value (valve opening drive signal) is output to the hydraulic control solenoid valve 20 by the friction member fastening means indicated by 0. At the hydraulic control solenoid valve 20, the hydraulic pressure is increased and the forward clutch 54 is engaged.

As the hydraulic pressure rises, the forward clutch 54
Starts fastening, and the turbine speed detected by the turbine sensor 16 decreases accordingly. Block 11
The friction member fastening completion determining means shown in FIG. 1 determines the termination based on the turbine speed based on “turbine speed <threshold value”. If the condition is not satisfied, the throttle fully closed holding means shown in block 112 As a result, the throttle operation permission flag is turned OFF, and the throttle controller 11 with the DC servo is turned off.
A signal is transmitted to the ECU 8 that controls the operation of the throttle, and the throttle is fully closed. Thereafter, the flow returns to the friction member fastening means shown in block 110, and the engagement oil pressure command value is increased to urge the engagement of the forward clutch 54.

On the other hand, if the condition is satisfied, block 11
The throttle operation permission flag is turned on by the throttle operation permission means shown in FIG. 3, and a signal is transmitted to the ECU 8 for controlling the operation of the DC servo-equipped throttle controller 11, thereby permitting the throttle operation.

[0061]

As described above, according to the control device for an automatic transmission of the present invention, when the vehicle is determined to have a gradient or a load that causes the vehicle to retreat or damage the friction member. By prohibiting the control, it is possible to improve drivability and prevent performance degradation of the friction member.

If the friction member is not completely engaged when the neutral control is canceled, the throttle is kept fully closed to prevent the engine speed from rising and reduce the shock when the friction member is engaged. .

[Brief description of the drawings]

FIG. 1 is a system schematic diagram of a vehicle including a control device for an automatic transmission according to an embodiment of the present invention.

FIG. 2 is a functional block diagram illustrating an outline of a control device of the automatic transmission in FIG. 1;

FIG. 3 is a cross-sectional view illustrating a main part of the automatic transmission illustrated in FIG. 1;

FIG. 4 is a flowchart showing the operation of the control device for the automatic transmission of FIG. 1;

FIG. 5 is a diagram illustrating the balance of each torque element.

FIG. 6 is a logic diagram for judging the start of control according to the present invention.

FIG. 7 is a diagram illustrating an example of a control pattern of a control device of the automatic transmission.

FIG. 8 is an embodiment of slip control according to the present invention.

FIG. 9 is a logic diagram for determining control release according to the present invention.

FIG. 10 is an operation diagram of control release according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Automatic transmission (AT) 3 ... Drive shaft (propeller shaft) 4 ... Differential device 5 ... Driving wheel 6 ... Hydraulic circuit 7 ... Automatic transmission control unit (ATCU) 8 ... ECU 9 ... Air cleaner 10 ... Air flow sensor 11 ... Throttle controller 12 ... Suction manifold 13 ... Injector 14 ... Torque converter 15 ... Gear train 16 ... Turbine sensor 17 ... Vehicle speed sensor 18 ... Throttle sensor 19 ... Idle speed control valve (ISC) 20 ... Hydraulic control solenoid Valve 41 ... Foot brake SW 42 ... Parking brake SW 43 ... Accelerator opening sensor 51 ... Input shaft 52 ... Output shaft 53 ... Band brake 54 ... Forward clutch 55 ... Forward one-way clutch 56 ... Low & reverse brake 57 ... Reverse clutch 58 ... High clutch 59 ... Overrun clutch 60 ... Low one way clutch

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Claims (7)

[Claims] 1. An automatic transmission control device for transmitting an output of an output rotary shaft of a vehicle engine to a transmission via a friction member, controlling engagement / disengagement of the friction member, and controlling the transmission. Even when the shift range is set to the forward traveling range, when the predetermined condition is satisfied, the friction member is released, and the automatic transmission includes a neutral control unit that controls the transmission to a neutral state. The control device, further comprising: vehicle state detecting means for detecting a running condition of the vehicle, wherein the neutral control means is configured to detect the running condition of the vehicle detected by the vehicle state detecting means if a value representing the running condition is equal to or greater than a certain value. A control device for an automatic transmission, characterized in that release of the friction member is prohibited or restricted even when a predetermined condition is satisfied. 2. A control device for an automatic transmission according to claim 1, wherein said vehicle state detecting means has a gradient detecting means for detecting a gradient of the vehicle, and said neutral control means detects by said detecting means. If the gradient of the vehicle is equal to or more than a certain value, the friction member is not completely released, and the friction member is maintained in a slip state. 3. The control device for an automatic transmission according to claim 1, wherein said vehicle state detecting means has a loading amount detecting means for detecting a loading amount of the vehicle, and said neutral control means is provided by said detecting means. A control device for an automatic transmission, wherein release of the friction member is prohibited if the detected load amount is equal to or greater than a certain value. 4. A control device for an automatic transmission according to claim 1, wherein said vehicle state detecting means has a load amount detecting means for detecting a load amount of a vehicle, and said neutral control means is provided by said detecting means. If the detected load is equal to or greater than a certain value, the friction member is not completely released and the friction member is kept in a slip state. 5. A control device for an automatic transmission according to claim 1, wherein said vehicle state detecting means has a gradient detecting means for detecting a gradient of the vehicle and a loading amount detecting means for detecting a loading amount of the vehicle. A control device for an automatic transmission, wherein the neutral control means prohibits release of the friction member based on a combination of a gradient and a load amount detected by the two detection means. 6. A control device for an automatic transmission according to claim 1, wherein said vehicle state detecting means has a gradient detecting means for detecting a gradient of the vehicle and a load detecting means for detecting a load of the vehicle. An automatic transmission, wherein the neutral control means does not completely release the friction member but keeps the friction member in a slip state by a combination of the gradient and the load amount detected by the two detection means. Control device. 7. The control device for an automatic transmission according to claim 1, wherein said vehicle state detecting means includes accelerator pedal opening degree detecting means for detecting an opening degree of an accelerator pedal. A throttle control device for the internal combustion engine that is not directly connected to the engine and is controlled by an opening signal detected by the accelerator pedal opening detecting means. Irrespective of the signal, when the release of the friction member is determined during the release of the friction member, the throttle is kept in a fully closed state until the engagement of the friction member is completed. apparatus.