JPS61282135A - Control device for vehicle automatic speed change gear - Google Patents

Abstract

PURPOSE:To ease gear shift shocks upon shift operation from a stopping range to a travel range, by decreasing the engine torque along with the shift of a travel range frictional engaging device into an engaging condition so that the engagement of the travel range frictional engaging device is carried out without a delay. CONSTITUTION:A shift position sensor (shift operation detecting means) 112 for detecting the shift position is connected to an ECT computer 50. Meanwhile, an intake-air temperature sensor 100, a throttle sensor (engine load detecting means) 102, a water temperature sensor 104 for detecting the temperature of cooling water, a crank angle sensor, etc. are connected to an engine computer 40. Due to shift operation from a stopping range to a travel range, the torque of the engine is decreased when the engine load (throttle) exceeds a predetermined value along with the engagement of a travel range frictional engaging device with no delay. As a result gear shift shocks during gear shift operation are suitably eased without the design of the hydraulic control device side being altered.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a control device for an automatic transmission for a vehicle, and more particularly to an improvement in a control device for an automatic transmission for a vehicle to reduce shift shock that occurs when a shift lever is moved to a driving range at the time of starting. (Prior art) In a vehicle equipped with an automatic transmission, for example, when a sudden start is required, the driver shifts to neutral while depressing the accelerator pedal.
D from the stop range such as microwave or P (parking) range.
When performing a range shift to a driving range such as the (drive) range, a large shift shock may occur. For example, compared to shifting between each drive stage, such as between the first and second gears, in the case of an N-D shift, the torque converter changes from a state where the engine can freely rev up by stepping on the accelerator. This is because the power is transmitted to the output shaft whose rotational speed is zero through. In other words, when switching to the driving range is performed while the accelerator is depressed,
The friction engagement device for the travel range does not end its engagement in the servo oil pressure buffer Ill region (usually formed by an accumulator), and slips into the servo oil pressure rising region where the buffer region has ended, and this servo oil pressure increases. This is because the output shaft torque of the automatic transmission rapidly increases as the force acting on the travel range friction engagement device rapidly increases in the oil pressure rapidly increasing region. In two-wheel drive vehicles such as so-called FF%FR, such shift shock can be alleviated to some extent by slipping of the drive wheels, but the weakest part of the drive system may be damaged by the impact load at this time. However, the amount of work and power of the frictional engagement device for the travel range become excessive, and the frictional engagement @
There is also a risk of fire damage to the equipment. Furthermore, in a four-wheel drive vehicle, the driving force is dispersed and slippage of the driving wheels is less likely to occur, so in order to achieve both wj impact load,
It is necessary to increase the capacity of each component of the drive system including the capacity of the frictional engagement device of the automatic transmission, which is a significant disadvantage in terms of manufacturing cost, 1L, and size.

[Problems to be solved by the invention]

However, when trying to solve these problems in the hydraulic control system of an automatic transmission by increasing the capacity of the accumulator or connecting the accumulators in multiple stages, the accumulator becomes larger, the weight increases, Or, it may lead to disadvantages such as the decoupling of IOM.
In reality, this is an extremely difficult problem. On the other hand, Japanese Patent Application No. 58-112665 discloses that when there is a shift operation from the stop range to the drive range, the engine rotation speed is reduced to the idling rotation speed without immediately starting the engagement operation of the friction engagement device for the drive range. Although the engagement operation is started after the vehicle has been lowered to 1, the engagement of the friction engagement device for the travel range is delayed, and actual start may be delayed, contrary to the driver's intention to hurry up.

[Purpose of the invention]

The present invention was made in consideration of such conventional problems, and is a friction engagement IA! for driving ranges. An object of the present invention is to provide control 1@1 for an automatic transmission for a vehicle, which can moderate the shift shock when there is a shift operation from a stop range to a drive range without delaying the engagement of the transmission. .

[Means to solve the problem]

The present invention includes a shift operation detection means for detecting a shift operation from a stop range to a running range, a means for detecting engine load, and a means for detecting a shift operation from a stop range to a drive range. The above object has been achieved by providing a torque reducing means for reducing the engine torque in parallel with the transition of the travel range frictional engagement device to the engaged state when the torque is greater than or equal to the torque value. Further, in the embodiment of the present invention, as the means for detecting the engine load, a means for detecting the throttle opening, the amount of fuel supplied per engine revolution, the intake negative pressure, or the output torque of the engine is adopted, and the engine This allows the load to be detected appropriately. Further, in another embodiment of the present invention, as the engine torque reducing means, one that controls ignition timing, fuel supply amount, intake air amount, opening/closing timing of intake and exhaust valves, or supercharging pressure is adopted. , the engine torque can be reduced smoothly and reliably. Also, other fruits of the present invention! l! In this aspect, the torque reduction means is operated for a predetermined period of time after a predetermined period of time (including zero) has elapsed from the point in time when the shift to the driving range is performed, so that the reduction in the engine torque is caused to occur when the engine torque is not in the driving range. This is done in parallel with the transition of the range frictional engagement device to the engaged state.

[Effect]

In the present invention, when the driver attempts to suddenly start with a shift operation, that is, when there is a shift operation from the stop range to the drive range, and when the engine load is determined to be greater than a predetermined value, f! Since the engine torque is reduced in parallel with the transition of the Il friction engagement device to the engaged state, the torque applied to each drive system component including the friction engagement device for the travel range is permissible. It is possible to maintain the respective durability within the specified range. In addition, since the input torque to the automatic transmission is suppressed within a predetermined value, the engagement of the friction engagement device for the travel range is reduced to 1L.
The shift ends within the ifll range, and an increase in shift shock is prevented.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an overall schematic diagram of an automatic transmission (hereinafter referred to as ECT) combined with an intake air port sensing type automobile electronic fuel injection engine to which the present invention is applied. The air taken in from the air cleaner 10 is connected to an air flow meter 12, an intake throttle valve 14, a surge tank 16,
The air is sequentially sent to the intake manifold 18. This air is mixed with fuel injected from the injector 22 near the intake boat 20, and further passed through the intake valve 24 to the engine body 26.
is sent to the combustion chamber 26A. combustion! The exhaust gas generated as a result of combustion of the air-fuel mixture in the exhaust valve 26A
8. Exhaust boat 3o, exhaust manifold 32 and exhaust pipe (
(not shown) is released into the atmosphere. The air 70-meter 12 is provided with an intake air temperature sensor 100 for detecting the air intake air temperature. The intake throttle valve 14 rotates in conjunction with an unspecified accelerator pedal provided at the driver's seat. This intake throttle valve 14 has a throttle sensor (engine load detection means) 102 for detecting its opening degree.
is provided. Further, a water temperature sensor 104 for detecting the engine cooling water temperature is disposed in the cylinder block 26B of the engine main body 26. Further, the destroyer 38 having a shaft rotated by the crankshaft of the engine body 26 is provided with a crank angle sensor 108 for detecting a crank angle from the rotation of the shaft. The ECT is also provided with a vehicle speed sensor 110 for detecting the vehicle speed from the rotational speed of its output shaft, and a shift position sensor (shift operation detection means) 112 for detecting the shift position. Each of these sensors 100, 102.104.108.1
The output of 10.112 is input to the engine computer 40. The engine computer 40 calculates the fuel injection amount and optimum ignition timing using the input signals from each sensor as parameters, and controls the injector 22 to inject fuel for a predetermined time period corresponding to the fuel injection amount. The ignition coil 44 is controlled so as to obtain the optimum ignition timing. Further, an idle rotation speed control valve 42 driven by a step motor is provided in a bypass passage that communicates the upstream side of the intake throttle valve 14 with the surge tank 16.
A signal from the engine computer 40 controls the idle speed. On the other hand, the ECT transmission section 900 in this embodiment includes a torque converter 910, an overdrive mechanism 920, and an underdrive mechanism 930. The torque converter 910 is a well-known one including a pump 911, a turbine 912, and a stator 913, and includes a lock-up clutch 914. The overdrive mechanism 920 includes a sun gear 921,
A planetary binion 922 meshing with the sun gear 921
, a carrier 92 supporting the planetary binion 922
3. Ring gear 9 meshing with planetary binion 922
One set of games consisting of 24! gear! Equipped with a device, this play 1I
The rotation status of the IIIN device is determined by the clutch Cos Brake B
It is controlled by O% and one-way clutch Fo. The underdrive mechanism 930 has a common sun gear 9
31, planetary pinions 932, 933 meshing with the sun gear 931, planetary pinions 932, 933;
Carrier 934.935 that supports, ring gear 936.937 that meshes with planetary pinion 932.933
The rotation state of this planetary gear II device and the connection state with the overdrive mechanism are controlled by clutches C and C2, brakes 81 to B3, and one-way clutches F+ and F2. It's in control. Since this transmission unit itself is well known, the connection state of each component will only be shown in a skeleton diagram in FIG. 1, and detailed explanation will be omitted. The ECT in this embodiment includes the transmission unit 900 as described above, and the ECT computer 50 receives signals from the throttle sensor 102, heavy speed sensor 110, etc., and controls the hydraulic control circuit 60 according to a preset shift pattern. 1@Magnetic valves S1 to S4 are driven and controlled, llf! Each clutch, as shown in Figure 2,
A combination of engagements of brakes and the like is performed to perform speed change control. In FIG. 2, the O mark indicates the operating state, the Δ mark indicates the operating state only when driving, and the X mark indicates the operating state only when the engine brake is used. Further, the solenoid valve S1. S
2 controls the speed change of the underdrive mechanism 930;
The solenoid valve S3 controls the overdrive mechanism 920, and the solenoid valve S4 controls the lock-up clutch 91.
4 controls are performed respectively. In such a device, the engine computer 4
0 receives shift information (shift determination, shift command, lock-up clutch engagement permission, etc.) from the ECT computer 50 and executes engine torque control in relation to signals from the throttle sensor 102 and shift position sensor 112. In addition, in this embodiment, the engine computer 40 and the EC
Although the T computer 50 is separate from the T computer 50, the present invention does not limit the number of control devices or the range m of control devices. Next, the operation of this embodiment will be explained. The engine torque control of the vehicle in this embodiment is executed according to the flowchart shown in FIG. This flowchart is started and executed every IC)++s, for example. First, in step 200, the shift position sensor 1
The shift position of Ei is detected by the signal from 12. If it is in either the stop range (N range or P range), in steps 202 and 204, the timer T1 flag! Clear and exit. In the case of an automatic transmission, the engine cannot be started unless the shift lever is placed in the neutral position due to the function of the neutral safety switch.
The flow terminated via 02.204 is executed first. Therefore, due to the existence of step 200, it is possible to detect whether there has been a shift operation from the stop range to the drive range, regardless of whether the engine is started or after the engine is started. When it is detected in step 200 that there has been a shift to the driving range, the process proceeds to step 206, where the timer flag T is increased by ΔK. Here, 6th is the pruritus cycle. In step 208, if the timer T is shorter than the predetermined value of 11T, (sec), the process is immediately terminated, and when the timer T becomes greater than 0, the process proceeds to step 210, where a comparison with the predetermined WiT3 is performed. If the timer T is smaller than the predetermined value 1tll T 3, the process proceeds to step 212, where it is determined whether the throttle opening degree θ detected by the throttle sensor 102 is larger than the predetermined value θa. If the throttle opening θ is larger than the predetermined value θa, in step 214, the amount of torque reduction corresponding to the throttle opening θ is searched using a preset ignition retard map, etc., as shown in FIG. Then, in step 216, a torque down command is issued, and in step 218, the I flag is set to 1. In addition to retarding the ignition timing, the torque reduction in step 216 can also be achieved by reducing the amount of fuel supplied, reducing the intake air layer, or shifting the opening/closing timing of the intake and exhaust valves. . Note that the reason why the flag I is set to 1 is to determine whether or not a torque down command is currently being issued within this flow field. On the other hand, when it is determined in step 212 that the throttle opening degree θ is smaller than the predetermined value θa, step 2
Proceed to step 20 and determine flag (■). Initially, flag I is cleared to zero in step 204, so the flow is ended as is. That is, when the throttle opening degree θ is smaller than the predetermined value θa, engine torque down control is not performed. After the flag ■ is set to 1 in the previous step 218, the process proceeds to steps 200 and 206, where ΔT is further added to the timer T, and then the process proceeds to step 210 via step 208. Timer T is specified! While it is still smaller than I T s,
Proceeding to step 212, it is determined whether the throttle opening degree θ is larger than the predetermined value θa, as described above, and if it is, the torque reduction corresponding to the throttle opening degree θ at that time is continued. Also, the throttle opening θ is set to the predetermined value θ.
When it is determined that the flag is smaller than a, the process proceeds to step 220 and the flag I is determined.
is 1, so after a torque return command is issued in step 222, 7 lags (2) are cleared to zero in step 224. Meanwhile, such a routine is repeated several times, and at step 210, the timer T reaches a predetermined value P! If it is determined that the flag has become larger than
A torque return command is issued at step 22, and step 224
In this case, flag I is cleared to zero. If we follow the above flow according to actual gear shifting, when there is a shift operation from the stop range to the drive range, the timer T
is started, and the timer T reaches a predetermined time fi! When it becomes more than Tosec, it is determined whether the throttle opening degree θ is above a predetermined value eaLI, and if it is more than the predetermined value 88, torque reduction is performed. When the throttle opening degree θ is maintained above the predetermined value θa, the torque is reduced to T3880. When the time exceeds T3 sec, a torque return command is issued and the torque down is completed. If the throttle opening degree θ becomes smaller than the predetermined value θa until T, sea has elapsed, a torque return command is issued at this point and the torque down is completed. If the travel range continues after T s sea, the process goes through steps 210 and 220 and does nothing. Note that the To timer cuts unnecessary torque down control, and for a certain period of time after shifting from the stop range to the drive range, the friction engagement for the drive range is activated. Although this is provided in consideration of the fact that the engagement of the shifter does not start, this value may be set to zero considering conditions such as shifting at the rear of the accelerator or shifting while depressing the accelerator. Alternatively, the engine torque may be gradually restored over a certain period of time. FIG. 5 is a diagram showing the output shaft torque of the automatic transmission when the above embodiment device is used in comparison with the conventional one. In the figure, the left end indicates the point in time when the shift from the stop range to the drive range is performed. Initially, regardless of the throttle opening θ, there is a grace period of T, tea from the time of this shift, and if the throttle opening θ is higher than the predetermined value θa after T, tea, then The reduction in engine torque begins and continues until 73 seconds have elapsed after the shift. As a result,
In the past, as shown by the solid line in the figure, hydraulic pressure! 1Il
If! Although the variation in the output shaft torque due to engagement not being completed within the 4th region was extremely large, in the above embodiment, this variation can be significantly suppressed as shown by the dashed line in the figure. In addition, in the above embodiment, the retardation of the ignition timing was used as a means to change the engine torque, but the present invention is not limited to the means for reducing the engine torque, and the above-mentioned method is not limited. For example, means such as reducing the fuel injection amount, reducing the intake air amount, or controlling the opening/closing timing of the intake and exhaust valves may be used. Further, in the above embodiment, the throttle opening degree was used as a means for detecting the engine load, but in the present invention, the detection of the engine load is not limited to this, for example, It can also be detected by detecting the fuel supply amount, intake negative pressure, or engine output shaft torque. [Effect of the Invention 1] As explained above, according to the present invention, when the accelerator is depressed while shifting from the stop range to the drive range, it is possible to complete the shift and start the vehicle with less time lag. The excellent effect is that the shift shock at that time can be kept extremely small without any particular change in the design of the hydraulic control system.

[Brief explanation of drawings]

The first factor is a partial block line showing the overall configuration of an automatic transmission combined with an intake air amount sensing type electronic fuel injection engine, which is an embodiment of the control device for a vehicle automatic transmission according to the present invention. 2 is a diagram showing the operating state of the frictional engagement device at each gear stage of the automatic transmission,
FIG. 3 is a flowchart showing a routine for changing the engine torque, FIG. 4 is a diagram showing an example of a map for determining the amount of change in ignition timing, and FIG. Engine torque, oil pressure,
S+V+ shows the relationship between the output shaft torque of the automatic transmission and the throttle opening along the time axis. 40... Engine computer, 50... ECT computer, 60... Hydraulic control circuit, 102... Throttle sensor (engine load detection means), 112... Shift position sensor (shift operation detection means).

Claims (4)

[Claims] (1) Shift operation detection means for detecting a shift operation from the stop range to the drive range, means for detecting engine load, and a shift operation from the stop range to the drive range, and the engine load is at a predetermined value. Control of an automatic transmission for a vehicle, characterized in that it is provided with: a torque reduction means for reducing engine torque in parallel with the transition of the travel range friction engagement device to the engaged state when the above is the case; Device. (2) The vehicle according to claim 1, wherein the means for detecting the engine load detects a throttle opening, an amount of fuel supplied per engine revolution, an intake negative pressure, or an output torque of the engine. Automatic transmission control device. (3) The torque reducing means includes ignition timing, fuel supply amount,
The control device for a vehicle automatic transmission according to claim 1 or 2, which controls an amount of intake air, opening/closing timing of intake and exhaust valves, or supercharging pressure. (4) The torque reduction means is operated only for a predetermined time after a predetermined time (including zero) has elapsed from the time when the shift to the driving range is performed. The control device for a vehicle automatic transmission according to any one of Item 3.