JPH04334734A - Integratedly controlling device for automatic transmission and engine - Google Patents

Abstract

PURPOSE:To carry out good change-gear by controlling output of an engine, so as to carry out gearshift, of an automatic transmission under condition of no disturbance in the output of the engine, and also to match a gear position with the engine output intended by a driver at an early time after gearshift and smoothly. CONSTITUTION:An auxiliary throttle valve is driven so as to set up the ideal engine torque (Tm) during gearshift operation (step 310), and solution of the difference between a demanded engine torque and an engine torque actually outputted on the basis of characteristic of the ideal engine torque (Tm), is started by an acceleration opening from a change-gear last period (prior to completion of inertia phase to a certain extents) (step 350). After gearshift is completed (the inertia phase is completed), the residual difference is solved by annealing process.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission and engine integrated control system that integrally controls an engine and an automatic transmission that transmits the output of the engine to drive wheels.

0002

2. Description of the Related Art Conventionally, for example, in Japanese Patent Publication No. 60-18862, engine output is
For example, a technique has been disclosed in which the gear shift is fixed to the value at the start of the gear shift and the gear shift is executed in a state where a specific predictable engine output is input.

[0003] According to this technology, since a stable (predictable) engine output is input to the automatic transmission, changes in the engine output (disturbance) during the gear shifting process can cause
Mismatching between the control hydraulic pressure in the hydraulic control device and the handled transfer energy can be prevented from occurring, and good shift characteristics can always be obtained.

0004

[Problem to be Solved by the Invention] However, it is difficult to maintain the engine output at a predetermined value during the gear shifting process (
control), there will naturally remain a deviation between the engine output required based on the accelerator pedal operated by the driver and the actual engine output at the end of the gear shift, and it is necessary to work to eliminate this. must be carried out.

However, if the deviation between the actual output and the required output is resolved after the gear shift is completely completed, the shift shock can certainly be reduced, but the time lag between the accelerator operation and the actual engine output will increase. That's how big it gets,
In addition to increasing the sense of discomfort, responsiveness will be greatly impaired, for example, when the driver requests acceleration.

The present invention has been made in view of these problems, and aims to prevent as much as possible the difference in correspondence between the driver's accelerator operation and the actual output while maintaining good shifting characteristics. This is an attempt to solve the above-mentioned problems by preventing the occurrence of discomfort and preventing a decrease in power responsiveness.

[0007]

[Means for Solving the Problems] The present invention, as summarized in FIG. A means of determining torque,
means for determining the required engine torque based on the accelerator opening degree; engine torque control means for controlling the engine torque regardless of the required engine torque so that the actual engine torque during shifting becomes the ideal engine torque; means for detecting the end of the shift, and detecting the difference between the requested engine torque based on the accelerator opening and the actual engine torque actually output based on the characteristics of the ideal engine torque at the end of the shift where the shift has not yet been completed; The above-mentioned problem is solved by providing means for issuing a command to the engine torque control means in order to start solving the problem.

[0008]

In the present invention, the engine output is uniquely determined until the end of the shift based on the actual output of the automatic transmission at the beginning of the shift (or the required output based on the operation of the accelerator pedal).

This determination method is as follows: (1) The actual output (or required output) of the engine at the initial stage of the shift is maintained as it is. (2) It is possible to gradually increase or decrease the actual output (or required output) until the end of the shift based on a preset slope based on the accelerator operation at the beginning of the shift.

[0010] As a result, the control oil pressure generated in the hydraulic control device of the automatic transmission and the transmitted energy input into the automatic transmission are different from each other due to the unpredictability of the engine output increasing and decreasing during gear shifting. This makes it possible to prevent a shift shock from becoming large due to mismatching, or from prolonging the shift time and reducing the durability of the friction engagement device.

By the way, when the actual engine output is controlled so that the ideal engine output is achieved during gear shifting,
Naturally, at the end of the shift, a deviation occurs between the requested output based on the accelerator operation and the actual output that is currently being generated.

In the present invention, the elimination of this deviation is not performed from the end of the shift, but rather the end of the shift is detected and the elimination of the deviation is started before the shift is completed.

As a result, sudden increases or decreases in engine output after shifting are alleviated,
It becomes possible to perform gear changes with less discomfort.

[0014]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows an overall outline of a vehicle automatic transmission to which this embodiment is applied.

This automatic transmission has a torque converter 20, an overdrive section 40, and an underdrive section 6 with three forward speeds and one reverse speed as its transmission sections.
0.

The torque converter 20 includes a pump 21
, a turbine 22, a stator 23, and a lock-up clutch 24. The pump 21 is connected to the crankshaft 10 of the engine 1, and the turbine 22 is connected to a carrier 41 of a planetary gear system in an overdrive section 40.

In the overdrive section 40,
A planetary pinion 42 rotatably supported by this carrier 41 meshes with a sun gear 43 and a ring gear 44 . Further, a clutch C0 and a one-way clutch F0 are provided between the sun gear 43 and the carrier 41, and a brake B0 is provided between the sun gear 43 and the housing Hu.

The underdrive section 60 is provided with two rows of planetary gears, one on the front side and the other on the rear side. This planetary gear device has a common sun gear 6.
1, ring gears 62, 63, planetary pinion 64,
65, and carriers 66 and 67.

Ring gear 44 of overdrive section 40
is connected to the ring gear 62 via a clutch C1. Further, a clutch C2 is provided between the ring gear 44 and the sun gear 61. Further, the carrier 66 is connected to the ring gear 63, and the carrier 66 and the ring gear 63 are connected to the output shaft 70.
is connected to.

On the other hand, the carrier 67 and the housing Hu
Brake B3 and one-way clutch F2 are connected between
is provided, and furthermore, a sun gear 61 and a housing H are provided.
A brake B2 is provided between the sun gear 61 and the housing H via a one-way clutch F1.
A brake B1 is provided between the brake B1 and the brake B1.

This automatic transmission includes a transmission section as described above, and includes a throttle sensor 100 that detects the throttle opening that reflects the load condition of the engine 1.
, an accelerator opening sensor 101 that detects the amount of depression of the accelerator pedal by the driver, and a vehicle speed sensor 10 that detects the vehicle speed.
The automatic transmission control computer 104A to which the signal No. 2 is input drives and controls the electromagnetic solenoid valves S1 to S3 in the hydraulic control circuit 106 according to a preset shift pattern, as shown in FIG. A combination of engagement of each clutch, brake, etc. is performed to perform speed change control.

In FIG. 3, the mark ◎ indicates that the relevant clutch or brake is engaged, and the mark ◎ indicates that the one-way clutch is engaged during driving.

Note that in FIG. 2, reference numeral 110 is a shift position sensor, which is operated by the driver for N, D,
112 is a pattern select switch that selects E (economic driving), P (power driving), etc., and 114 is a rotation speed sensor that detects the rotation speed of the engine. 116 is a foot brake, and 118 is a brake switch for detecting the operation of the handbrake.

In this embodiment, in addition to these input signals, the automatic transmission control computer 104A receives a signal from the C2 sensor 120 for detecting the drum rotation speed of the clutch C2, and a signal from the C2 sensor 120 for detecting the drum rotation speed of the clutch C2.
A signal from a C0 sensor 121 for detecting the drum rotation speed Nco is also input.

Further, the engine 1 has its fuel injection amount, ignition timing, etc. controlled by an engine control computer 104B, and this engine control computer 104B has a control computer 104B that controls engine torque from an automatic transmission control computer 104A. A signal SG1 is input. Engine control computer 104B receives this signal SG1 from automatic transmission control computer 104A.
The engine 1 is controlled so that the engine torque becomes a predetermined value based on the command.

[0027] As for the structure itself for controlling the engine torque, a well-known structure can be adopted. For example, a method of controlling ignition timing may be adopted, a configuration in which a throttle valve or a sub-throttle valve is controlled by a motor, or a configuration using a combination of these may be adopted. good.

In this embodiment, in addition to the normal throttle valve that is driven in conjunction with the accelerator pedal, a sub-throttle valve (not shown) that is driven by a motor is provided in series with the throttle valve. The opening degree is controlled electronically.

FIGS. 4 to 6 show control flows executed in the apparatus of the above embodiment.

First, in step 210, signals from various sensors are input. For example, the accelerator opening θ, vehicle speed V, engine rotational speed Ne, pattern select switch select signal, etc. are input.

In step 220, it is determined whether or not there has been a shift determination, that is, whether the current running state has crossed a threshold value on a shift pattern that is preset according to the vehicle speed--throttle opening. If there is no shift determination, this control flow is ended as it is not related to this control.

[0032] When there is a shift judgment, step 230
Then, it is determined whether or not this shift determination is an upshift. Further, in step 240, it is determined whether the upshift is from the third gear to the fourth gear, and in step 250, it is determined whether the upshift is from the second gear to the third gear. is judged.

This control flow is substantially executed only when an upshift from the second gear to the third gear is executed.

That is, when it is determined that a shift from the second gear to the third gear should be executed, the process proceeds to step 260, where a signal output to that effect (switching output of the solenoid valve) is first output. After that, in step 270, the engine rotational speed Ne and the accelerator opening degree θ are read. Here, each value is read in the torque phase at the start of the shift.

In step 280, an ideal engine torque Tm is calculated from the read engine speed Ne and accelerator opening θ. In this example,
This ideal engine torque Tm is set so as not to change during gear shifting. Furthermore, this ideal engine torque Tm
may be changed according to changes in the actual accelerator opening degree θ within an allowable range.

At step 290, the rate of change Δθ of the accelerator opening is calculated. In step 300, it is determined whether the rate of change Δθ of the accelerator opening is greater than a predetermined value α. When the rate of change Δθ of the accelerator opening degree is larger than the predetermined value α, it is predicted that the accelerator opening degree will change significantly during the gear shift, so this control is stopped.

This is to prevent the correction control width from becoming extremely large after the end of the shift. In other words, the accelerator opening degree θ
When the rate of change Δθ of This will prevent you from shifting the gears you want.
In this case, emphasis is placed on acceleration performance even if some shift shock occurs.

Note that this predetermined value α may be changed depending on driving conditions (eg, vehicle speed V, type of gear change, etc.).

In step 310, the sub-throttle valve is controlled to achieve the calculated ideal engine torque Tm. The opening degree THm of this sub-throttle valve is determined by the engine rotational speed Ne, the accelerator opening degree θ, and the time t.
It becomes a function of That is, even if the accelerator opening degree θ changes and the required engine torque Tr changes, the opening degree of the sub-throttle valve is controlled so as not to be affected by the change, and the actual engine torque Te is changed to the ideal engine torque Tm.
It is intended to be controlled.

In step 320, the end of the shift is determined. This judgment is Nc0≦N0 ×i +β1
Judgment is made based on whether the following holds true or not. Here, N0
is the rotational speed of the output shaft 70 (synonymous with the signal of the vehicle speed sensor 102), i is the gear ratio in the third gear, and β1 is a constant. Note that this β1 may be changed depending on driving conditions, such as the accelerator opening degree θ and the vehicle speed V.

[0041] Until it is determined that the shift has reached the final stage,
So-called loop processing is performed. Eventually, when it is determined that the shift has reached its final stage, the process proceeds to step 330, where the required engine torque Tr at this time is calculated from the engine rotational speed Ne and the accelerator opening θ.

Further, in step 340, the ideal engine torque Tm and the required engine torque Tr are compared. If this difference is smaller than the predetermined value γ, the process proceeds to step 390 and flag F is set to 1. This flag F is a flag indicating that learning correction may be performed.

Thereafter, the process proceeds to step 360, where the sub-throttle valve is controlled so that the actual engine torque Te becomes the required engine torque Tr.

On the other hand, if the difference between the ideal engine torque Tm and the required engine torque Tr is larger than the predetermined value γ, the process proceeds to step 350, where the ideal engine torque Tm is corrected to a new Tm. The method of this modification is such that, for example, the new Tm is set to a value such as (Tr - Tm)/2. This is to avoid abruptly modifying the engine torque at the end of the gear shift.

Thereafter, the process proceeds to step 360, where the sub-throttle valve is driven so that the actual engine torque Te becomes the new Tm. In step 370, it is determined whether the inertia phase has ended. This judgment is Nc0
The determination is made based on whether or not ≦N0 ×i +β2 holds true. Here, β2 is a constant smaller than β1.

The flow from steps 330 to 360 is repeated until it is determined that the inertia phase has ended. Eventually, when it is determined that the inertia phase has ended, the process proceeds to step 380, where the required engine torque Tr obtained from the engine rotational speed Ne and the accelerator opening degree θ is determined again.
is calculated, and the subthrottle smoothing process is performed so that the actual engine torque Te gradually approaches the required engine torque Tr. As a result, the engine torque starts to approach the required engine torque Tr according to the accelerator opening degree θ from the end of the gear shift (slightly before the end of the inertia phase), and the request that had been deviated before and after the end of the inertia phase starts to approach. The difference between the engine torque and the actual engine torque will be eliminated.

After this, in step 410, it is determined whether or not the flag F is 1. If the flag F is determined to be 1, that is, the accelerator opening θ is too low during the gear shift.
If it is detected that there is no change in
Then, the shift time is detected and a predetermined time, for example, C
2 Hydraulic learning correction is executed.

Thereafter, flag F is reset to 0 in step 430, and this flow ends. When the flag F is 0, the flow ends without particularly performing any learning correction.

FIG. 7 is a diagram showing the shift characteristics when the above control flow is executed.

As is clear from the figure, when the accelerator opening θ increases, the fluctuation of the output shaft torque T0 increases as shown by the dashed line, but in this embodiment, as shown by the broken line, The ideal engine torque Tm is kept constant for most of the gear shift, and as a result, the actual engine torque Te
will also be kept constant. Therefore, on the automatic transmission side, it becomes possible to shift gears in a state where there is no disturbance at all, and therefore it becomes possible to execute gear shifts with small shift shocks in accordance with the specifications.

Furthermore, since the elimination of the difference between the required engine torque Tr and the actual engine torque Te is started at the end of the shift (slightly before the inertia phase), the difference is eliminated after the shift is completed. Compared to the conventional method, the required engine torque and the actual engine torque can be matched more smoothly and earlier.

[0052]

[Effects of the Invention] As explained above, according to the present invention, an automatic transmission can change gears while the engine output is always constant or gradually increases or decreases as scheduled (so to speak). It becomes possible to perform a shift without any disturbance), and it becomes possible to perform a shift with a small shift shock.

Furthermore, in this case, the difference between the actual engine torque generated at the end of the shift and the engine torque requested by the driver (according to the accelerator opening) is started to be resolved before the end of the shift. Therefore, it is possible to achieve the excellent effect that the cancellation can be executed more smoothly, and the time required for the engine output to finally reach the level corresponding to the accelerator opening can be shortened.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating the gist of the present invention.

FIG. 2 is a skeleton diagram of an integrated automatic transmission and engine control device to which an embodiment of the present invention is applied.

FIG. 3 is a diagram showing the engagement state of each frictional engagement device in the automatic transmission.

FIG. 4 is a flowchart showing a control flow executed in the apparatus of the embodiment.

FIG. 5 is a control flow continuing from FIG. 4;

[6] FIG. 6 is a control flow showing the continuation.

FIG. 7 is a diagram showing shift characteristics when the above control flow is executed.

[Explanation of symbols]

104A...Automatic transmission control computer, 10
4B...Engine control computer, θ...Accelerator opening degree, Tr...Required engine torque based on accelerator opening degree θ,
Tm...Ideal engine torque.

Claims (1)

[Claims] 1. An automatic transmission and engine integrated control device configured to control engine output during gear shifting, comprising means for determining an ideal engine torque during gear shifting, and means for determining required engine torque based on an accelerator opening degree. ,
engine torque control means for controlling engine torque regardless of the requested engine torque so that the actual engine torque during gear shifting becomes the ideal engine torque; means for detecting the final stage of gear shifting; A command is given to the engine torque control means to start eliminating the difference between the requested engine torque and the actual engine torque that has been actually output based on the characteristics of the ideal engine torque from the final stage of the shift, where the shift has not yet been completed. 1. An integrated control device for an automatic transmission and an engine, characterized in that it is equipped with means for issuing.