JP2961974B2 - Shift control device for automatic transmission for vehicle - Google Patents

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 more particularly to a shift control device for an automatic transmission for a vehicle which may execute a clutch-to-clutch shift.

[0002]

BACKGROUND OF THE INVENTION In order to achieve a particular shift in an automatic transmission, it is often necessary to simultaneously engage and disengage two frictional engagement devices (a so-called clutch-to-clutch shift). In this case, if the synchronization and disengagement of the respective friction engagement devices are not properly synchronized, the gear train of the automatic transmission instantaneously becomes rigid or neutral, and the output shaft torque is reduced. There was a possibility of a sudden descent or an engine spike.

For this reason, when such control is conventionally performed, a one-way clutch having a function substantially equivalent to the function of one of the friction engagement devices is provided to prevent such a problem from occurring. ing.

However, the method of synchronizing the respective friction engagement devices by using the one-way clutch as described above has problems such as an increase in weight and occupation of a housing space due to the provision of the one-way clutch. .

In view of such a point, in recent years, the following technique has been disclosed as a technique for achieving such a "clutch-to-clutch shift" without using a one-way clutch (SAE). Paper 890529).

According to this technique, when performing a so-called clutch-to-clutch shift control in which one frictional engagement device is released and another frictional engagement device is engaged when a specific shift is achieved. For example, in the case of an upshift in a power-off state (a driven state in which power is transmitted from the wheel side to the engine side), first, the engine rotation speed is shifted by changing the synchronous rotation after shifting the frictional engagement device on the release side. The speed drops to near the speed, where the engagement side frictional engagement device is engaged.

[0007]

However, in practice, it is very difficult to perform the engagement on the engagement side when the engine rotation speed is near the synchronized rotation speed after shifting under various operating conditions. It is.

In this case, for example, when the engagement of the frictional engagement device on the engagement side is accelerated due to an upshift with the power off, a so-called overlap state occurs, and the output torque changes from negative to positive. A strong shift shock occurs.

For this reason, as a control mode, it is conceivable to execute the clutch-to-clutch shift while the engagement of the friction engagement device on the engagement side is delayed so as to be in a so-called under-up state.

[0010] Alternatively, it is conceivable to change (reduce) the engine output to prevent the engine from blowing up while performing underlap control.

[0011] However, the output of the engine is not always in a state where it can always be reduced, and sometimes it cannot be reduced.

For example, in the case where the engine output is reduced by retarding the ignition timing, the temperature of the catalyst usually rises. Therefore, when the temperature of the catalyst exceeds a certain value, the engine output is reduced. Measures that prohibit the reduction of emissions are often adopted.

When the automatic transmission and the engine are controlled by separate computers and a command signal for output down control is transmitted from the automatic transmission control computer to the engine control computer in accordance with the shift control, the signal line In some cases, disconnection or short circuit may occur. In this case, the engine output is not reduced based on the reason that it is better not to reduce the engine output at all, rather than to reduce it based on an abnormal signal. Sometimes.

As described above, when the engine output cannot be reduced, for example, when the clutch-to-clutch shift is directly executed by the underlap control, there arises a problem that the engine easily blows up.

The present invention has been made in view of such a problem, and has been made in consideration of the performance of the clutch-to-clutch shift.
Stoppage can be controlled rationally, preventing problems such as engine spattering from occurring and shifting gears.
SUMMARY OF THE INVENTION An object of the present invention is to provide a shift control device for an automatic transmission for a vehicle , which is capable of reducing the cost, and to solve the above-mentioned problems.

[0016]

Means for Solving the Problems The present invention, as shown from the gist thereof in FIG. 1 (A), the shift control system for an automatic transmission for a vehicle with running the clutch-, during shifting Means for reducing the engine output, means for detecting whether or not reduction of the engine output by the engine output reducing means is permitted, and means for determining the gear position of the automatic transmission based on the vehicle state. ,
The clutch-to-clutch shift selection control for permitting the execution of the clutch-to-clutch shift when the reduction of the engine output during the shift is permitted, and for inhibiting the clutch-to-clutch shift when the engine output is reduced during the shift. Means are provided to solve the above problem. FIG. 1B shows the gist of the present invention.
In some vehicles, clutch-to-clutch shifting may be performed
The shift control device for a dual-purpose automatic transmission, wherein the clutch
Whether the execution of the toe clutch shift should be allowed or prohibited
Means for determining, and the result of the determination, the clutch-to-clutch
If it is determined that shifting should be prohibited, shift to the next shifting
The gear ratio intervals in the clutch
Means for performing a shift that does not result in a shift.
The present invention has also solved the above-mentioned problem.

[0017]

According to the first aspect of the present invention, when executing the clutch-to-clutch shift, the engine output is reduced during the shift. As a result, even when the vehicle enters the underlap state or is actively controlled to be in the underlap state, it is possible to accurately prevent the engine from blowing up.

On the other hand, when the reduction of the engine output is restricted for the above-described reason, the clutch-to-clutch shift is prohibited, so that the occurrence of problems such as engine spikes can be accurately determined. Can be prevented.

It should be noted that when the clutch-to-clutch shift is prohibited, there are several methods to be concretely dealt with.

For example, the clutch-to-clutch shift is simply prohibited as it is, and the driving state of the vehicle is kept waiting until there is a "new shift decision" that the vehicle should be shifted to a speed that does not cause the clutch-to-clutch shift. Alternatively, a plurality of gear stages (gear trains) may be provided as in an embodiment to be described later, and by changing the selection of the gear stages, clutch-to-clutch shifting is prevented. (Claims 2 and 4) . On the other hand, claim 2
In the invention of the third aspect, the execution of the clutch-to-clutch shift is permitted.
Should be prohibited or should be prohibited (for example,
Is determined to be prohibited)
The gear ratio in the next gear shift,
Perform shifts that are not latch-to-clutch shifts
I have to. In this way, the gear is shifted to the gear having the gear ratio closest to the prohibited gear ratio .
(Claim 3) .

[0021]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 2 is an overall schematic diagram of an integrated control device for an automatic transmission and an engine to which the present invention is applied.

The engine 1 has its injection valve 19 controlled by an engine control computer 7.
And the ignition timing at the distributor 20 are controlled, and an engine output corresponding to the accelerator opening (operating amount) of the accelerator pedal 22 and the engine speed is obtained.

That is, a main throttle valve 26 that opens and closes in conjunction with the movement of an accelerator pedal 22 and a motor driven by a command from the engine control computer 7 irrespective of the accelerator pedal 22 are provided in an intake pipe 24 of the engine 1. A sub-throttle valve 30, which is opened and closed in conjunction with the movement of the throttle valve 28, is arranged in series, and the function of the two throttle valves 26, 30 realizes the present invention.

That is, since the main throttle valve 26 is directly connected to the accelerator pedal, the accelerator operation amount and the engine output linearly correspond to each other. However, the opening of the sub throttle valve 30 can be freely set. Therefore, a throttle opening having intended characteristics can be obtained as a whole. Specifically, since they are in series, they are governed by the smaller opening of the two.

The method of reducing the engine output may be based on other known means. For example, the ignition timing may be retarded, or the fuel injection amount may be reduced.

The automatic transmission 2 is controlled by the automatic transmission control computer 8 to operate the solenoid valves S1 to S1 of the hydraulic control device 3.
S4 is controlled, and as a result of the change of the oil passage in the hydraulic control device 3, the engagement state of each friction engagement device is selectively changed,
The shift speed corresponding to the vehicle speed and the accelerator opening can be obtained.

The engine control computer 7 includes an engine rotation speed detected by an engine rotation sensor 9, an intake air amount detected by an intake air amount sensor 10, and an intake air temperature sensor 1.
1, the accelerator opening by the accelerator opening sensor 12, the vehicle speed by the vehicle speed sensor 13, the engine water temperature by the engine water temperature sensor 14, the brake switch 1
5 are input.

The engine control computer 7 determines the fuel injection amount and the ignition timing based on these signals.

On the other hand, the automatic transmission control computer 8 includes the accelerator opening sensor 12 and the vehicle speed sensor 1.
3. In addition to the signals from the engine water temperature sensor 14, the brake switch 15, etc., the position of the shift lever by the shift position sensor 16, the pattern select switch 17
A driving selection pattern such as fuel-conservation-oriented traveling or power-performance-oriented traveling, and a signal for permitting a shift to overdrive by the overdrive switch 18 are input to obtain a speed corresponding to the vehicle speed and the accelerator opening. The solenoid valves S1 to S4 are ON-OFF controlled.

FIG. 3 is a skeleton diagram showing a specific example of the automatic transmission 2 described above. The automatic transmission 2 includes a torque converter 111, an auxiliary transmission unit 112, and a main transmission unit 113.

The torque converter 111 has a lock-up clutch 124. The lock-up clutch 124 is provided between a front cover 127 integrated with the pump impeller 126 and a member (hub) 129 integrally mounted with the turbine runner 128.

The crankshaft (not shown) of the engine 1 is connected to a front cover 127. The input shaft 130 connected to the turbine runner 128 is connected to the overdrive planetary gear mechanism 13
And one carrier 132.

In the planetary gear mechanism 131, a clutch C0 and a one-way clutch F0 are provided between the carrier 132 and the sun gear 133. The one-way clutch F0 is engaged when the sun gear 133 rotates forward relative to the carrier 132 (rotation in the rotation direction of the input shaft 130).

On the other hand, a brake B0 for selectively stopping the rotation of the sun gear 133 is provided. Further, a ring gear 134 which is an output element of the auxiliary transmission section 112 is connected to an intermediate shaft 135 which is an input element of the main transmission section 113.

When the clutch C0 or the one-way clutch F0 is engaged, the auxiliary transmission portion 112
Since the whole of the shaft 31 rotates integrally, the intermediate shaft 135 is rotated.
Rotate at the same speed as the input shaft 130. When the brake B0 is engaged and the rotation of the sun gear 133 is stopped, the ring gear 134 is rotated forward with the speed increased with respect to the input shaft 130. That is, the subtransmission unit 112 can set high-low two-stage switching.

The main transmission unit 113 has three sets of planetary gear mechanisms 140, 150, and 160, and these gear mechanisms 140, 150, and 160 are connected as follows.

That is, the sun gear 141 of the first planetary gear mechanism 140 and the sun gear 151 of the second planetary gear mechanism 150 are integrally connected to each other, and the ring gear 143 of the first planetary gear mechanism 140 and the sun gear 151 of the second planetary gear mechanism 150 are connected. Carrier 1
52 and the carrier 162 of the third planetary gear mechanism 160 are connected. The output shaft 170 is connected to the carrier 162 of the third planetary gear mechanism 160. Further, a ring gear 153 of the second planetary gear mechanism 150 is connected to a sun gear 161 of the third planetary gear mechanism 160.

In the gear train of the main transmission portion 113, one reverse speed and four forward speeds can be set, and a clutch and a brake for that purpose are provided as follows.

That is, the ring gear 153 of the second planetary gear mechanism 150 and the sun gear 161 of the third planetary gear mechanism 160
A clutch C1 is provided between the intermediate shaft 135 and the sun gear 141 of the first planetary gear mechanism 140 and a sun gear 151 of the second planetary gear mechanism 150.

A brake B1 for stopping rotation of the sun gears 141 and 151 of the first planetary gear mechanism 140 and the second planetary gear mechanism 150 is provided. In addition, these sun gears 1
A one-way clutch F1 and a brake B2 are arranged in series between 41, 151 and the casing 171.
The one-way clutch F1 is engaged when the sun gears 141 and 151 try to rotate in the reverse direction (rotation in the direction opposite to the rotation direction of the input shaft 135).

Carrier 142 of first planetary gear mechanism 140
A brake B3 is provided between the motor and the casing 171. Also, the ring gear 16 of the third planetary gear mechanism 160
The brake B4 and the one-way clutch F2 are arranged in parallel between the casing 171 and the brake B4 as elements for stopping the rotation of the motor 3. The one-way clutch F2 is adapted to be engaged when the ring gear 163 attempts to rotate in the reverse direction.

In the automatic transmission 2 described above, the auxiliary transmission portion 112
Can perform high-low two-stage switching, and the main transmission unit 113 can perform four-stage shifting on the forward side, so that a total of one reverse stage and eight forward stages can be performed. it can. FIG. 4 shows an engagement operation table of each clutch and brake for setting these shift speeds. In FIG. 4, a circle indicates an engaged state, a closed circle indicates an engaged state during engine braking, and a blank indicates a released state.

The shift control device shown in FIG. 2 has a plurality of shift maps as storage contents of the automatic transmission control computer 8, and among them, the shift map used in the D range includes the vehicle speed V and the accelerator opening. There are different speed change maps of a plurality of speed stages set according to the degree θ. FIGS. 5 and 6 show examples of the gear stages.

The gear sequence shown in FIG. 5 (hereinafter referred to as the A gear train) includes the first, second, and second gears among the eight gears shown in FIG.
It is composed of the third, fourth and fifth gears, and the fifth gear (5t
Except for h), it is a gear sequence including five gear stages set to the sub-gear stage 12 at the low speed stage (low). FIG. 7 shows an example of this map.

The gear sequence shown in FIG. 6 (hereinafter referred to as a B gear train) has the first, 1.5, and 1.5 gears among the eight gears shown in FIG.
2.5, 3.5, 4.5 (= 5) speed stages,
7 is a shift speed train including five shift speeds set with the sub-transmission portion 12 set to a high speed (high) except for the first speed. FIG. 8 shows an example of this map.

In each of the gear trains A and B, the speed of the entire automatic transmission 2 can be achieved by shifting only one of the auxiliary transmission portion 112 and the main transmission portion 113. Transmission sections 112 and 11
3 so that there is no shift which must be shifted simultaneously (synchronously).

It is also possible to change the gear train to be adopted during traveling. For example, a shift between the second speed in the A gear train and the 2.5th speed in the B gear train, and the gear shift in the A gear train can be changed. 3rd gear and B
Shifting between the third speed of the gear train and the third speed can be achieved without switching the main transmission unit 113 and shifting the subtransmission unit 112 to high or low without simultaneous transmission.
When a predetermined condition is satisfied, a shift between these shift speeds occurs.

Further, the second speed in the A gear train and the second speed in the B gear train
The 3.5th gear is a shift that is achieved by shifting both the main transmission unit 113 and the subtransmission unit 112, but is relatively easy to control because the shift direction is common, This shift can also occur.
FIG. 9 is a schematic diagram of the above-described shiftable state.

When a shift from A to B or from B to A is executed between different gear trains, thereafter, in principle, gear shift is executed using the gear train to which the gear belongs. Is done.

FIG. 10 shows a control flow executed by the apparatus of the above embodiment.

First, in step 210, input processing of various signals is performed. For example, signals such as the vehicle speed V, the accelerator opening θ, and the engine coolant temperature T are read here.

In step 220, it is determined whether the position of the shift lever is in the N range. If it is in the N range, the routine proceeds to step 230, where the brake B0
Is returned after performing the engagement process.

If it is determined that the range is not the N range, the routine proceeds to step 240, where it is determined whether or not the range is the D range. If it is not in the D range, the process returns.

On the other hand, if the engine is in the D range, the routine proceeds to step 250, where it is determined whether or not engine output control (during shifting) is possible. This determination is made, for example, when the communication line between the engine control computer 7 and the automatic transmission control computer 8 fails (open circuit or short circuit), or when the sub throttle valve 130
When a failure occurs in the wiring system of the motor 128 for driving the motor, a flag is set by a separate control flow, and the value of this flag is read.

When the output control of the engine is achieved by retarding the ignition timing, for example, it is determined that the engine output cannot be controlled when the catalyst temperature exceeds a predetermined value. Configuration.

As a result of this determination, when the control of the engine output is permitted, the maps of both the A gear train and the B gear train can be used, that is, the shift shown in FIG. 9 can be executed. Is done. More specifically, in normal times,
Starting from the 1.5th gear, the B gear train is used.
Accordingly, the clutch-to-clutch shift between the second and third speeds is also performed. However, since the B gear train is used in such a manner as to be decelerated by the sub-transmission unit 112 and increased in the main transmission unit 113, it is not necessarily a favorable mode in terms of fuel efficiency, noise, and the like. For example, when predetermined conditions such as upshift and downshift when the accelerator pedal is released are satisfied, switching between the B gear train and the A gear train may be performed according to the arrow in FIG.

On the other hand, if it is determined in step 250 that the engine output during shifting cannot be reduced,
Proceeding to step 270, only a dedicated map for the A gear train is prepared, and the gear position is determined according to this. Therefore,
A clutch-to-clutch shift between the 2.5th gear and the 3.5th gear does not occur, and good gear shifting characteristics can be obtained even if the engine output cannot be reduced.

Note that there is no one-way clutch provided directly in parallel with the brakes B2 and B3 involved between the second speed and the third speed in the A gear train. Although the shift is effected, it is possible to execute a shift similar to the case of using a one-way clutch using the one-way clutch F0 by involving the clutch C0 (known technology: Japanese Patent Publication No. 56-35773).
In addition to the present embodiment, the shift using the complete one-way clutch can be replaced with the shift between the 2.5th and 3.5th speeds.

[0060]

As described above, according to the present invention, a clutch-to-clutch shift is permitted when the engine output can be reduced during a shift, and a shift with a desired gear ratio is achieved without increasing shift shock. On the other hand,
Since the clutch-to-clutch shift itself does not occur in a state where the reduction of the engine output is restricted, it is possible to rationally balance the execution of the shift with the desired gear ratio and the prevention of engine injection. become able to.

[Brief description of the drawings]

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

FIG. 2 is a schematic block diagram showing an embodiment of the present invention.

FIG. 3 is a skeleton diagram showing a gear train of the apparatus of the embodiment.

FIG. 4 is a diagram showing an operation state of each friction engagement device of the gear train.

FIG. 5 is a diagram for setting each shift speed of an A gear train.

FIG. 6 is a diagram for setting each shift speed of a B gear train.

FIG. 7 is a shift map for executing a shift according to a B gear train.

FIG. 8 is a shift map for executing a shift according to an A gear train.

FIG. 9 is a diagram schematically illustrating a mode in which gear shifting can be performed by the apparatus of the embodiment.

FIG. 10 is a flowchart showing a control flow executed in the apparatus of the embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Automatic transmission, 7 ... Engine control computer, 8 ... Automatic transmission control computer, 126 ... Main throttle valve, 128 ... Motor, 130 ... Subthrottle valve, Brake B2, B3 ... 2.5th speed , A brake that provides a clutch-to-clutch shift between the 3.5th gears.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuo Hojo 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Kazumasa Tsukamoto 10 Takane Fujiimachi Anjo City, Aichi Prefecture Aisin Ai (72) Inventor Masahiro Hayabuchi 10 Takane, Fujii-machi, Anjo, Aichi Prefecture Aisin A. Inc. (72) Inventor, Masahiko Ando 10 Takane, Fujii-machi, Anjo, Aichi Aisin Ai JP-A-4-34539 (JP, A) JP-A-2-218828 (JP, A) JP-A-62-165050 (JP, A) JP-A-62-137459 (JP) JP-A-62-131830 (JP, A) JP-A-2-23265 (JP, A) JP-A-4-136439 (JP, A) JP-A-3-107551 (JP, A) (58) Investigation The field (Int.Cl. ^6, DB name) B60K 41/04

Claims (4)

(57) [Claims] 1. A shift control device for an automatic transmission for a vehicle, which may execute a clutch-to-clutch shift, comprising: an engine output reducing means for reducing an engine output during a shift; and a reduction of the engine output by the engine output reducing means. Means for detecting whether or not the clutch is in a permitted state; means for determining the gear position of the automatic transmission based on the vehicle state; and when the reduction of the engine output during the shift is permitted, the clutch A shift control device for an automatic transmission for a vehicle, comprising: clutch-to-clutch shift selection control means for permitting execution of a clutch shift and for inhibiting clutch-to-clutch shift when in a restricted state. . (2) In claim 1, further, With two or more gear trains, When the execution of the clutch-to-clutch shift is prohibited
Indicates that execution of clutch-to-clutch shifting is permitted
Use the gear stage that is not used for
A shift that does not become a two-clutch shift is executed.
Transmission control device for an automatic transmission for a vehicle. (3) Executing clutch-to-clutch shifting
In a shift control device for a vehicle automatic transmission with Whether the execution of the clutch-to-clutch shift should be permitted or prohibited
Means for determining whether to stop, As a result of the judgment, execution of clutch-to-clutch shift is prohibited.
If it is determined that it is necessary to
The gap is different so that the clutch-to-clutch shift does not
Means for performing the speed; Shift control for an automatic transmission for a vehicle, comprising:
apparatus. (4) In claim 3, further, With two or more gear trains, As a result of the determination, execution of the clutch-to-clutch shift is prohibited.
If it is determined that the clutch should be
The gear to use when it is determined that speed execution should be allowed
By using a different gear train from the train, the gear ratio spacing
Shifting of an automatic transmission for a vehicle, characterized in that
Control device.