JPS61279762A - Method of controlling vehicle engine torque - Google Patents

Abstract

PURPOSE:To make it possible to always maintain a satisfactory gear shift characteristic irrespective of whether the temperature of intake-air is high or low, by changing the engine torque by a predetermined amount in accordance with the temperature of engine intake-air during an automatic speed change gear being shifted. CONSTITUTION:The transmission section 900 of an automatic speed change gear (ECT) is subjected to the control of speed shift by an ECT computer 50 which controls a hydraulic control circuit 60 in accordance with signals from a throttle sensor 102, a vehicle speed sensor 110, etc. An engine receives the data of gear shift from the above-mentioned computer 50, and an engine computer 40 controls the engine torque so that it is decreased and decreased by a predetermined values during gear shift. In the above-mentioned arrangement, the engine torque is controlled to be increased and decreased during gear shift by a predetermined amount which is set in accordance with the intake-air temperature detected by an intake-air temperature sensor 100 and which is set with reference to a map relating to the temperature of intake-air.

Description

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

The present invention relates to a method for controlling engine torque of a vehicle.
□Especially in vehicles equipped with automatic transmissions, good shift characteristics can be obtained in relation to engine intake air temperature.□
The engine torque of a vehicle that can be
11 relates to a control method.

[Conventional technology 1] Conventionally, extraction was performed depending on the temperature of the engine intake air.
It is well known that the output of carrots varies.
:] In particular, the degree of change is large in engines with superchargers, for example, as shown in Figure 8, at 45℃
1. Engine change of more than 10% for a change in suction temperature of 1. ,, :・： Changes in torque may occur.・
1; On the other hand, the friction engagement device of an automatic transmission is
1.45゜According to the load (throttle opening, etc.), the working oil pressure
Generally, things that change... Therefore, if the engine torque changes due to the change in intake air temperature as described above even though the throttle opening is the same, the engine torque will increase relative to the working oil pressure and the engagement time will increase. This may lead to problems such as the length becoming longer or, conversely, the working oil pressure becoming relatively too high and causing a large shift shock. Generally, in the former case, the durability of the rIi friction engagement device may be deteriorated, so when setting the working oil pressure of an automatic transmission, the working oil pressure should be set higher in anticipation of an increase in engine torque. In other words, the setting must be made on the side where the shift shock is large. In order to solve this problem W4, the operating oil pressure of the frictional engagement device of the automatic transmission must be made variable in accordance with the intake air temperature. [Problems to be Solved by the Invention] However, this method requires an actuator and the like for controlling the clutch hydraulic pressure, which poses a problem in that it leads to significant modification of the current mechanism and an increase in cost. On the other hand, when trying to solve the above-mentioned problem on the engine side to make it compatible with automatic transmission, when the intake air temperature is low, part of the performance is reduced so that the output is the same as when it is high. However, it is not a reasonable method from the viewpoint of power performance and fuel consumption.

[Purpose of the invention]

The present invention has been made in view of these conventional problems, and it is possible to improve the intake air temperature without deteriorating the power performance, fuel efficiency, etc. of the engine, or without changing the design of the automatic transmission. It is an object of the present invention to provide a method for controlling engine torque of a vehicle, which can always obtain good speed change characteristics regardless of the height of the torque, and can improve the durability of a frictional engagement device.

[Means to solve problems]

The present invention provides an engine torque control method for a vehicle equipped with an automatic transmission, as summarized in FIG. The above object is achieved by including the step of changing the engine torque by a predetermined amount during gear shifting of the aircraft. Further, in an embodiment of the present invention, the predetermined amount is set based on a map related to the intake air temperature, so that the engine torque is always appropriately changed. In addition, Mr. M who implements the present invention, when the intake air temperature is high,
The predetermined amount is set to zero, and the engine torque is changed fIII only when the intake air temperature is low, thereby eliminating the control flow. Further, in the present invention, the engine torque is changed by retarding the ignition timing, reducing the fuel injection amount, or reducing the intake air amount, thereby increasing the engine torque with good response. This allows for changes to be made.

[Effect]

In the present invention, when the engine torque changes due to a change in the intake air temperature, this change poses a problem in terms of compatibility with the automatic transmission only during gear shifts of the automatic transmission. By focusing on this, we changed the engine torque by a predetermined amount according to the intake air temperature only during gear shifting, which resulted in good results in terms of shift shock and durability without requiring any design changes on the automatic transmission side. The output shaft torque of the automatic transmission is determined by the connection force (working hydraulic pressure) of the frictional engagement device of the automatic transmission during gear shifting.
), so the power output during gear shifting is determined by
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■It is something that will never change.

[Example 1] An example of the present invention will be described in detail below with reference to the drawings.
I will clarify. FIG. 2 shows an example of an engine in combination with an electronic fuel injection engine for an automobile that detects the amount of intake air, to which the present invention is applied.
Overview of the automatic transmission (hereinafter referred to as ECT)7
□It is a factor. The air taken in from the air cleaner 1o 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 26A for combustion. The exhaust gas generated as a result of combustion of the air-fuel mixture in the combustion chamber 26A passes through the exhaust valve 2.
8. Exhaust boat 30, exhaust manifold 32 and exhaust pipe (
(not shown) is released into the atmosphere. The air flow meter 12 is provided with an intake temperature sensor 100 for detecting intake temperature. The intake throttle valve 14 rotates in conjunction with an accelerator pedal (not shown) provided at the driver's seat. This intake throttle valve 14 is provided with a throttle sensor 102 for detecting its opening degree. 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 vehicle speed from the rotational speed of its output shaft, and a shift position sensor 112 for detecting a 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 4o calculates the fuel injection amount and optimal ignition timing using input signals from each sensor as parameters, and controls the injector 22 to inject fuel for a predetermined time corresponding to the fuel injection amount. The ignition oil 44 is controlled so that the optimum ignition timing is obtained. 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 machine 1i8920 has a sun gear 92
1. Planetary binion 9 meshing with H sun gear 921
22, a planetary gear set consisting of a carrier 923 that supports the planetary pinion 922, and a ring gear 924 that meshes with the planetary pinion 922, and the rotational state of this planetary gear set is controlled by a clutch CO, a brake BO,
and a one-way clutch Fo. The underdrive mechanism 930 has a common sun gear 9
31.1 Planetary binion 932.933 meshing with sun gear 931, said planetary binion 932.933
Carrier 934 supporting
``Goo 1! 21 consisting of v936 and 937) 1
1°W″@4i-@1. , :03m!i!11111
11+7) [[le j. state and the connection state with the overdrive mechanism are determined by clutches C1, C2, brakes 81 to B a , and
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TIJ Ill L T iru. Since this transmission section 900 is well known in the celestial body, the connection state of each component will only be shown as a skeleton in FIG.
■n・13, ECT in this example is the above-mentioned tiger:! Equipped with SHISMITSU 232 part 900, the engine body 2
・;6')FM*flffi#Lr°'81fifi
20VMLfbll! . A throttle sensor 102 detects the vehicle speed.
1:. Input the signal of the vehicle speed sensor 110 etc. to be detected.
11ECT-] The bullet is set in advance by the computer 50. The voltage in the hydraulic control circuit 6o is
□゛1 Magnetic valves S1 to S4 are driven and controlled, and the combination of engagement of each clutch, brake, etc. as shown in FIG. 3 is performed to perform speed change control. In addition, in FIG. 3, the ◯ mark indicates the operating state, the Δ mark indicates that the brake is active only when driving, and the x mark indicates that the operating state is only when the engine brake is used. In addition, the above [1 valve S+, S
z controls the speed change of the underdrive mechanism 930;
The solenoid valve S3 controls the overdrive mechanism 920, and the solenoid valve $4 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 a signal from the intake air temperature sensor 100. In addition, in this embodiment, the engine computer 40 and the EC
Although the T computer 50 is separate, the present invention does not limit the number of control devices or the areas to which they are assigned control. Next, the operation of this embodiment will be explained. Engine torque 1IljIII of the vehicle in this example
is performed according to a flowchart as shown in FIG. First, in step 200, the intake air temperature of the engine is detected by the intake air temperature sensor 100. Then step 2
The process proceeds to step 02, where a map for changing the engine torque is selected. An example of this map is shown in Figure 5. Here, ignition timing changes 11 (retard amounts) with respect to reference intake air temperatures (-10°C, 20°C, 35°C) are mapped according to the throttle opening degree for each type of speed change. Also, regarding the temperature between the reference intake air temperatures, as an example in Fig. 6, the throttle opening θ6
, θ, the amount of retardation is determined by complementary calculation. Note that this map may be used as a retardation amount with respect to the reference intake air temperature range. That is, for example, the intake air temperature ranges from 110°C to 01°C. ,a. -125,. 4,
. 1゜1,1o1'C(7) Hey. . , 23°. E10
6. . You can also set it like so. After the selection range of the retardation amount relative to the intake air temperature for changing the engine torque is determined in this way, a process is performed in which the engine torque is changed only while the automatic transmission is being shifted. That is, when a shift determination is made in step 204,
Proceeding to step 206, a shift command is issued. Next, in step 208, the timing to start changing the engine torque is determined based on whether the automatic transmission has entered the inertia phase. Here, the inertia phase is a period during which the rotating members of the automatic transmission change their rotational speeds for gear shifting, and the inertia phase is a period during which the rotating members of the automatic transmission change their rotational speeds for gear shifting. A timer lets you know when to start. When it is determined in step 208 that the inertia phase has started, in step 210, the amount of retardation of the ignition timing is specifically determined according to the type of shift and the throttle opening within the selected range for the previously selected intake air temperature. , in step 212, ignition retardation is performed. Thereafter, in step 214, the end of the inertia phase is detected, and in step 216, the ignition timing is restored. It should be noted that steps 300 to 308 are based on the inertia [the flow of the relevant flow until the phase starts and ends].
Step 1'-4 is related to setting of flag T to substantially stop the operation. According to this embodiment, depending on the intake air temperature,
□The amount of change in ignition timing (predetermined difference in engine torque change) is set based on the throttle opening at that time for each type of shift, so the intake air temperature
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r a M [(1>,, which does not have any adverse effect on gear shifting:. This will be explained in detail with reference to Fig. 7. Now, the working oil pressure P of the friction engagement device is as shown in Fig. Suppose that the intake air temperature is adjusted to 1i1L1.
. Changes in engine torque when changing from temperature to low humidity
The output shaft torque of the automatic transmission changes from the dashed-dotted line L2 in the figure to the solid line L3 depending on the change in the torque.In other words, the engagement in the frictional engagement device increases by the amount that the intake air temperature decreases and the engine torque increases. The time (opening during gear shifting) becomes longer, which causes problems in terms of durability.In order to avoid this problem, generally the working oil pressure P of the RJI friction engagement device is increased as shown by the two-dot chain line L4, and the automatic transmission is By changing the output shaft torque as shown by the two points 111iiL5, the amount of work of the frictional engagement device is limited to a certain range.In this case, the shift shock is sacrificed.Also, when the intake air temperature is low, In addition, if the working oil pressure P of the #frictional engagement device is set to a high value, if the intake air temperature increases and the engine torque decreases, it will fail!
A problem arises in that the shift shock becomes even greater as shown by L6. In this example, since the amount of change in engine torque is changed according to the intake air temperature, the input torque of the automatic transmission in the inertia phase is constant, and even if the intake air temperature becomes low, it is always maintained at the dashed line L2 in the figure. Good shifting characteristics as shown can be obtained. In addition, in the above embodiment, in view of the fact that changing the engine torque during gear shifting generally makes it possible to maintain good gear shifting characteristics, the engine torque is always slightly changed even when the intake air temperature is not low. Although it is (actually [
(See IL7, L8) 1. In the present invention, it is not always necessary to change the engine torque; for example, the engine torque may be changed only when the intake air temperature is lower than a predetermined temperature. Good too. Furthermore, in the above embodiment, the engine torque was changed by changing the ignition timing (retard);
In the present invention, the means for changing the engine torque is not limited, and it can be realized by, for example, reducing the amount of fuel injection or reducing the amount of intake air. Furthermore, in the above embodiment, the throttle opening (engine load) at that time is determined for each type of shift depending on the intake air temperature.
Although the amount of change in ignition timing is set based on the above, it is also possible to set the amount of change in ignition timing based on vehicle speed instead of engine load. Effects of the Invention As explained above, according to the present invention, even if the output torque of the engine changes due to a change in the intake air temperature, the automatic transmission does not change the output torque due to the intake air temperature when shifting. Since the changes are input in a corrected form, it is possible to always maintain good shifting characteristics regardless of the high or low intake air temperature, and it is also possible to maintain good durability. An excellent effect can be obtained.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing the gist of the vehicle engine torque control method according to the present invention, and FIG. 2 is a flowchart showing the outline of the vehicle engine torque control method according to the present invention.
Figure 3 is a cross-sectional view, including a partial block diagram, showing the overall configuration of an automatic transmission combined with an intake air amount sensing type electronic fuel injection engine to which the 111 method is applied. Fig. 4 is a flowchart showing the engine torque change routine, and Fig. 5 is a diagram showing the operating state of each friction engagement device at each gear stage.
Tsua, )□yo, 1 “Figure 6 is,
Similarly, Figure 1 shows the complementary calculation method, Figure 7 is a diagram showing the relationship between working oil pressure, automatic transmission output shaft torque, and engine torque along the time axis, and Figure 8 is a diagram showing the relationship between the working oil pressure, the output shaft torque of the automatic transmission, and the engine torque. FIG. 3 is a diagram illustrating an example of the relationship between engine torque and engine torque. 26...Engine body, 40-=-1 engine 1-bita.
1°50... ECT computer, 60... Hydraulic control circuit, 100... Intake temperature sensor. ?

Claims (4)

[Claims] (1) An engine torque control method for a vehicle equipped with an automatic transmission, which includes a step of detecting an engine intake air temperature, and a predetermined amount of engine torque during shifting of the automatic transmission according to the engine intake air temperature. A method for controlling engine torque of a vehicle, comprising: a procedure for changing the engine torque; (2) The predetermined amount is set by a map related to the intake air temperature.
A method for controlling the engine torque of a vehicle as described in Section 1. (3) The engine torque control method for a vehicle according to claim 1 or 2, wherein the predetermined amount is set to zero when the intake air temperature is high. (4) The change in engine torque retards the ignition timing;
Claim 1, characterized in that the method is carried out by either reducing the amount of fuel injection or reducing the amount of intake air.
The method for controlling engine torque of a vehicle according to any one of items 1 to 3.