JPH0842680A - Vehicle automatic shift control device - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to configure an automatic gear shift control device without requiring a vehicle speed sensor, to achieve cost reduction, and to reduce the vehicle speed of an automatic gear shift control device having a vehicle speed sensor. It is possible to perform backup in the event of a sensor failure, to properly control the automatic transmission when the vehicle speed sensor fails, to avoid deterioration of driving performance, and to provide an automatic transmission control device based on engine speed and throttle opening. By comparison, it is possible to reduce restrictions on shifting such as shift points. Therefore, according to the present invention, in an automatic gear shift control device for a vehicle, control is performed to switch the engagement state of an auxiliary transmission mechanism of an automatic transmission based on an estimated vehicle speed calculated from an engine speed and an engine output torque. , When the shift position of the automatic transmission is shifted from the non-forward drive position to the forward drive position, the auxiliary transmission mechanism of the automatic transmission is controlled to switch to the engaged state of the highest speed and the engine speed input is If there is not, the control means for controlling the auxiliary transmission mechanism of the automatic transmission to switch to the engaged state of the highest speed shift stage is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic gear shift control device for a vehicle, and more particularly, to an automatic gear shift control device that does not require a vehicle speed sensor, can achieve cost reduction, and has a vehicle speed sensor. When the vehicle speed sensor of the automatic transmission control device fails, backup can be performed, and when the vehicle speed sensor fails, the automatic transmission can be appropriately controlled for shifting, avoiding deterioration of driving performance, engine speed and throttle opening. The present invention relates to an automatic gear shift control device for a vehicle, which can reduce restrictions on shifting such as a shift point, as compared with the automatic gear shift control device.

[0002]

2. Description of the Related Art In some vehicles, an automatic transmission is connected to a mounted engine and the engagement state of an auxiliary transmission mechanism of the automatic transmission is switched according to a running state. Examples of automatic shift control devices that control the shift of the automatic transmission include those that control based on vehicle speed and those that control based on engine speed and throttle opening.

As an automatic shift control device which controls on the basis of the vehicle speed, there is one disclosed in Japanese Patent Publication No. 63-31030. The publication disclosed in this publication controls the shift stage of the automatic transmission to the second speed or higher when the throttle opening is below a predetermined value and the vehicle speed is below a predetermined value and the shift position is changed from the neutral position to the drive position. When the throttle opening or the vehicle speed becomes equal to or higher than a predetermined value, the control is performed so as to return to the normal gear.

Further, the automatic transmission control device estimates the vehicle speed based on data calculated from other signals when the vehicle speed sensor for detecting the vehicle speed is out of order, and uses the estimated vehicle speed to determine the failure of the vehicle speed sensor or when the vehicle speed sensor fails. There are some fail-safe backups. As an automatic transmission control device for controlling by an estimated vehicle speed calculated from a signal other than the vehicle speed sensor, the automatic shift control device that controls on the basis of the estimated vehicle speed calculated from the engine speed and the engine output torque has been proposed by the applicant of the present invention. It has already been applied.

[0005]

However, when the estimated vehicle speed is used as a backup when the vehicle speed sensor fails, or when the estimated vehicle speed is used without using the vehicle speed sensor, the following problems occur. Occurs.

That is, since the automatic transmission cannot estimate the vehicle speed when the shift position is the neutral position (N range), the automatic transmission can shift from the neutral position, which is the non-forward traveling position, to the drive position (D range), which is the forward traveling position, or 2 When the auxiliary transmission mechanism is controlled to switch to the second speed engagement state or the first speed engagement state (the engine brake works) when shifting to the high speed position (2 range) or the low position (L range), the vehicle is In the running state, there is a problem that the vehicle is suddenly decelerated and the engine is over-rotated.

Further, in the automatic transmission, when the shift position is shifted to the drive position (D range) or the second speed position (2 range), the first speed is applied when the auxiliary speed change mechanism is in the first speed engaged state. Since the gear stage in the engaged state has the one-way clutch, the engine brake cannot be applied. Therefore, there is a problem that the vehicle speed cannot be estimated in the region where the engine is in the non-driving state shown by the diagonal lines in FIG.

For example, in a traveling state (downhill traveling) in which the vehicle speed gradually increases from 0 km / h with the throttle valve fully closed, the engine is in the driving state area until a certain vehicle speed (predetermined vehicle speed). Driving force is transmitted,
It is possible to accurately estimate the vehicle speed. However, when the vehicle speed increases above a certain vehicle speed (predetermined vehicle speed), the one-way clutch brings the same state as neutral, and as shown in FIG. 7, the estimated vehicle speed does not increase further and becomes constant with respect to the actual vehicle speed further increasing.

That is, in the region where the engine is not driven, even if the actual vehicle speed increases above the predetermined vehicle speed, the engine speed does not increase due to the one-way clutch, so the estimated vehicle speed does not increase.

For this reason, the automatic transmission maintains the engaged state of the first speed shift stage even though the vehicle speed should be shifted up to the engaged state of the second speed shift stage or the third speed shift stage. Therefore, there is a problem that the engine brake is not effective.

Further, when the estimated vehicle speed is used as a backup when the vehicle speed sensor fails, if the means for detecting the engine speed for calculating the estimated vehicle speed fails, the calculated estimated vehicle speed becomes 0 km / h. Become.

For this reason, the automatic transmission shifts when the estimated vehicle speed calculated as a result of failure of the means for detecting the engine speed becomes 0 km / h while the vehicle controlled by the estimated vehicle speed is running. There is a problem in that the vehicle is suddenly decelerated and the engine is excessively rotated by determining that the vehicle is down and switching to the engagement state of the low speed side gear.

[0013]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention controls to switch the engagement state of an auxiliary transmission mechanism of an automatic transmission connected to an engine mounted on a vehicle. In an automatic shift control device for a vehicle, a rotation speed sensor for detecting an engine rotation speed of the engine is provided, a torque sensor for detecting an engine output torque of the engine is provided, and an estimation calculated from the engine rotation speed and the engine output torque is provided. The auxiliary transmission mechanism of the automatic transmission is controlled to switch the engagement state of the auxiliary transmission mechanism of the automatic transmission based on the vehicle speed, and the auxiliary transmission of the automatic transmission is changed when the shift position of the automatic transmission is shifted from the non-forward traveling position to the forward traveling position. It is characterized in that control means is provided for controlling the mechanism to switch to the engaged state of the highest speed.

[0014]

According to the structure of the present invention, the automatic shift control device for a vehicle has the engagement state of the auxiliary shift mechanism of the automatic transmission based on the estimated vehicle speed calculated from the engine speed and the engine output torque by the control means. The automatic shift control device can be configured without the need for the vehicle speed sensor by performing control so as to switch the vehicle speed, and the automatic shift control device having the vehicle speed sensor can be backed up when the vehicle speed sensor fails.

Further, in this vehicle automatic shift control device, when the shift position of the automatic transmission is shifted from the non-forward traveling position to the forward traveling position by the control means, the auxiliary transmission mechanism of the automatic transmission is set to the highest speed stage. By controlling so as to switch to the engaged state of No. 3, it is possible to prevent the engaged state of the low speed side shift stage from being held regardless of the vehicle speed to be upshifted.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show an embodiment of the present invention. In FIG. 5, 2 is an engine mounted on a vehicle (not shown), 4 is a cylinder block, 6 is a cylinder head, 8 is a piston, 10 is a combustion chamber, 12 is an intake valve, 14
Is an exhaust valve, 16 is an intake manifold, 18 is an intake passage, 2
0 is a surge tank, 22 is a throttle valve, 24 is an air cleaner, 26 is an exhaust manifold, 28 is an exhaust passage,
Reference numeral 30 is an exhaust pipe, and 32 is a catalyzer (catalyst).

The engine 2 has a fuel injection valve 34 which directs fuel into the combustion chamber 10 to inject fuel into the intake manifold 16.
It is attached to. The fuel injection valve 34 is connected to the delivery pipe 36. One end of a fuel supply pipe 38 is connected to the delivery pipe 36. The other end of the fuel supply pipe 38 is connected to the fuel pump 40. The fuel pump 40 is installed in the fuel tank 42.

The delivery pipe 36 includes a connecting pipe 44.
Via pressure regulator (fuel pressure adjustment valve) 4
6 has been contacted. This pressure regulator 46
Is operated by the intake pressure in the surge tank 20 from the fuel pressure adjusting pressure pipe 48 to adjust the fuel pressure. A fuel return pipe 50 opening to the fuel tank 42 is connected to the pressure regulator 46.

The surge tank 20 includes a detection pressure pipe 5
One end side of 2 is connected. A pressure sensor 54 is provided on the other end side of the detection pressure pipe 52. The pressure sensor 54 detects the intake pressure in the surge tank 20. A throttle position sensor 56 is connected to the throttle valve 22 for detecting the opening state of the throttle valve 22. In the air cleaner 24,
An intake air temperature sensor 58 for detecting the intake air temperature inside the air cleaner 24 is attached.

Further, an O ₂ sensor 60 for detecting the oxygen concentration in the exhaust is attached to the exhaust manifold 26. A water temperature sensor 64 for detecting the temperature of the cooling water in the cooling water passage 62 formed in the cylinder block 4 is attached to the cylinder block 4.

A distributor 66 is attached to the cylinder head 6. The distributor 66 is provided with a crank angle sensor 68 that detects not only the crank angle but also the engine speed and functions as a speed sensor.

An automatic transmission 70 is connected to the engine 2. The automatic transmission 70 includes the torque converter 7
2 and the auxiliary transmission mechanism 74.

The automatic transmission 70 includes a valve body 7
6 is provided. Inside the valve body 76, there are provided a first solenoid valve 78 and a second solenoid valve 80, which are shift speed changing means for switching the engagement state of the shift speed of the auxiliary shift mechanism 74. Further, the valve body 76 is provided with an oil temperature sensor 82 that detects the oil temperature in the automatic transmission 70. The automatic transmission 70 is provided with a vehicle speed sensor 84 that detects a vehicle speed by rotating a rotating shaft (not shown).

The fuel injection valve 34, fuel pump 40, pressure sensor 54, throttle position sensor 56, intake air temperature sensor 58, O ₂ sensor 60, water temperature sensor 64, crank angle sensor 68, first solenoid valve 78, and second solenoid. Valve 80, oil temperature sensor 82, vehicle speed sensor 84
And are connected to the control means 88 of the vehicle automatic shift control device 86.

The control means 88 includes a shift switch 90 for detecting the shift position of a shift lever (not shown), an electric load switch 92, an air conditioner compressor switch 94, and a torque sensor 96 for detecting the engine output torque of the engine 2. Are connected. The shift switch 90 has shift levers of “P”, “R”, “N”,
It switches at "D", "2", and "L" positions, respectively, and outputs the signal at each position.

The control means 88 receives signals from various sensors, controls the operation of the fuel injection valve 34 to inject fuel, and controls the operation of the first and second solenoid valves 78 and 80 to control the automatic transmission 70. Shift.

In this way, the engine 2 mounted on the vehicle
A vehicle automatic transmission control device 8 for controlling to switch the engagement state of the auxiliary transmission mechanism 74 of the automatic transmission 70 connected to the vehicle.
6, a crank angle sensor 68 that is a rotation speed sensor that detects the engine rotation speed of the engine 2 is provided, and a torque sensor 96 that detects the engine output torque of the engine 2 is provided, and an estimation calculated from the engine rotation speed and the engine output torque is provided. The auxiliary transmission mechanism 74 of the automatic transmission 70 is controlled to switch the engagement state based on the vehicle speed, and when the shift position of the automatic transmission 70 is shifted from the non-forward traveling position to the forward traveling position, the automatic transmission 70 of the automatic transmission 70 is shifted. A control means 88 for controlling the auxiliary speed change mechanism 74 to switch to the engaged state of the highest speed is provided.

Further, the control means 88 sets the shift-up point when the auxiliary transmission mechanism 74 of the automatic transmission 70 is in the engaged state of the shift stage having the one-way clutch to the region where the engine 2 is in the driven state. It is set.

The estimated vehicle speed is calculated as follows. That is, in the automatic transmission 70 provided with the torque converter 72, since the torque converter 72 has a slip,
The vehicle speed is not proportional to the engine speed, and the vehicle speed cannot be simply estimated from the engine speed. In order to estimate the vehicle speed, it is necessary to consider the slip of the torque converter 72. The slip of the torque converter 72 is usually defined as the speed ratio of the torque converter 72.

Therefore, the speed ratio of the torque converter 72 can be calculated from the engine speed and the engine output torque. Focusing on the above, the speed ratio of the torque converter 72 is calculated from the engine speed and the engine output torque, and the vehicle speed is estimated based on this speed ratio.

For this reason, the control means 88 incorporates a torque converter performance curve map (shown in FIG. 3) and a speed ratio table (shown in FIG. 4). In addition, the control means 88 also incorporates a torque converter performance curve map (not shown) during reverse driving, a gear ratio-pump torque coefficient table (not shown), and the like.

Then, the control means 88 calculates the vehicle speed and the speed ratio of the torque converter 72 as follows.

In calculating the vehicle speed, in the automatic transmission 70 equipped with the torque converter 72, the vehicle speed (V
The relationship between s) and the engine speed (Ne) is given by the following equation. Vs = Km * ・ E ・ Ne …………………… (1) Km *: Input shaft speed-vehicle speed conversion coefficient However, * is Low 1km ₁ 2nd 2km ₂ 3nd 3km ₃ e: Torque converter speed ratio = n ₂ / n ₁ n ₁ : Pump speed n ₂ : Turbine speed

Km * Is a constant determined by the gear ratio of the automatic transmission 70 in each gear (gear stage). Therefore,
The vehicle speed Vs can be estimated by calculating the speed ratio (e).

In calculating the speed ratio (e), the torque converter performance curve is usually based on the speed ratio (e),
It is shown as in FIG. Focusing on the pump torque coefficient in FIG. 3, the pump torque coefficient (τ) and the speed ratio (e) are in a substantially one-to-one correspondence, and the pump torque coefficient (τ) is changed to the speed ratio (e). It can be seen that the calculation can be performed by searching the table as shown in FIG.

The pump torque coefficient (τ) is given by the following equation. τ = T ₁ / (n ₁ ) ² ………………………… (2) T ₁ : Pump torque n ₁ : Pump speed

The pump (not shown) of the torque converter 72 is normally directly connected to the crankshaft (not shown) of the engine 2, and T ₁ = T _EO ...................................... ………… (3) n ₁ = Ne …………………………………… (4) T _EO : Engine output torque _NE : Engine speed.

Therefore, τ = T _EO / (Ne) ² …………………… (5).

Therefore, it is understood that the vehicle speed can be estimated by calculating the speed ratio (e) from the engine output torque (T _EO ) and the engine speed (Ne).

Although the control means 88 is provided with the torque sensor 96 for detecting the engine generated torque, the engine output torque can be calculated by the intake air pressure detected by the pressure sensor 54. The engine output torque includes, for example, a table of delay time (delay time) of engine generated torque, loss (loss) and intake air pressure (P
b) and the table.

That is, the engine generated torque (T _EG ) is 1
It is known to be approximately proportional to the intake air amount per rotation. When this is expressed by intake air pressure (Pb), T _EG = K _TG · K _EV · Pb ………………………… (6) K _TG : Intake air pressure-generated torque conversion coefficient K _EV : Volume efficiency Pb: Intake air pressure (absolute pressure)

Of course, when the fuel is cut, T _EG = 0 …………………………………… (7).

In practice, a delay proportional to the rotation period occurs after the mixture is sucked into the combustion chamber 10 until it explodes to generate torque, so that the value calculated by the equation (6) is rotated. The engine generated torque (T _EG ) is obtained by applying a delay proportional to the cycle.

From the above, the generated torque can be calculated. However, in order to obtain the engine output torque (T _EO ), the loss torque must be subtracted. The loss torque is
Loss torque (T _LO ) of the engine 2 itself such as mechanical loss and pumping loss, and loss torque for driving auxiliary equipment such as air conditioner compressor driving torque (T _AC ) and electric load driving torque (T _EL ), There is.

[0045] _{Thus, T 'EO = T EGD -} (T LO + T AC + T EL) a ... (8).

The pumping loss changes depending on the intake air pressure. Therefore, T _LO is obtained by searching the table of the intake air pressure (Pb).

When the engine speed changes, a torque proportional to the change in the engine speed is generated due to the moment of inertia of the rotating part of the engine 2. Therefore, the engine output torque (T _EO ) is expressed by the following equation.

T _EO = T ′ _EO −K _NT · (ΔNe / Δt) = T _EGD − (T _LO + T _AC + T _EL ) −K _NT · (ΔNe / Δt) (9) K _NT : Rotational speed change-torque conversion coefficient

Next, the operation of this embodiment will be described with reference to the flowchart of FIG.

When the control is started (step 100), the engine speed Ne is compared with the engine stop determination speed NeS set to be equal to or lower than the idle speed (Ne <Ne.
S), and it is determined whether the engine 2 is stopped (step 102).

When the engine 2 is stopped, the vehicle speed cannot be estimated from the engine speed. Therefore, if the determination (step 102) is YES (when the engine 2 is stopped), a fail-safe process is performed to switch the auxiliary transmission mechanism 74 to the engaged state at the highest speed (step 104). It is the end (step 114).

When the air-safe is not performed, for example, when the means for detecting the engine speed (rotation speed sensor) during traveling fails and the engine speed is determined to be 0 rpm, the estimated vehicle speed becomes 0 km / h. , It is determined that the shift is down, and the shift state is switched to the engagement state of the low-speed gear. For this reason, there is a problem that the vehicle is suddenly decelerated and the engine 2 is excessively rotated.

Therefore, the judgment (step 102) is Y.
In the case of ES (when the engine 2 is stopped), as a fail-safe process, the auxiliary transmission mechanism 74 is switched to the engaged state of the highest speed shift stage (step 104), whereby the vehicle is suddenly decelerated or the engine 2 is overloaded. Prevent rotation.

When the determination (step 102) is NO (when the engine 2 is driven), the shift position of the automatic transmission 70 is shifted from the non-forward drive position (P, R, N) to the forward drive position (D). It is determined whether or not (step 10
6).

If this determination (step 106) is YES, the auxiliary transmission mechanism 74 is switched to the engaged state of the highest speed gear stage (step 104).

If the determination (step 106) is NO, the estimated vehicle speed is calculated from the engine speed and the engine output torque as described above (step 108). The vehicle speed is
It can be calculated from the gear ratio of each shift stage of the auxiliary transmission mechanism 74 of the automatic transmission 70 and the output speed of the torque converter 72. The output speed of the torque converter 72 can be estimated from the engine speed and the engine output torque. Therefore, the vehicle speed in each gear of the automatic transmission 70 can be estimated from the engine speed and the engine output torque.

When the shift position of the automatic transmission 70 is the non-forward drive position (P, R, N), the engagement state of the auxiliary transmission mechanism 74 is mechanically set. Therefore, the shift position of the automatic transmission 70 is the non-forward traveling position (P, R,
In the case of N), even if the estimated vehicle speed calculated is somewhat inaccurate, no problem will occur.

When the estimated vehicle speed is calculated in (step 108), the shift is judged based on the estimated vehicle speed (step 110). That is, the shift is determined from the shift map of the vehicle speed and the throttle opening based on the calculated estimated vehicle speed and the throttle opening.

In this judgment (step 110), when the gear shift is not required (the gear is not shifted), the end is reached (step 114). In this judgment (step 110),
If a shift is required (shift), the shift process is performed (step 112), and the process ends (step 114).

The shift process (step 112) is performed by switching the output to the first solenoid valve 78 and the second solenoid valve 80, which are the shift stage changing means in the valve body 76. In this speed change process (step 112), the first and second solenoid valves 7
It also performs timing control of output switching of 8/80, determination of shift completion, and the like.

In the shift process (step 112), when the engine 2 is stopped or the shift position of the automatic transmission 70 is shifted from the non-forward drive position (P, R, N) to the forward drive position (D). Then, by switching the output to the first and second solenoid valves 78 and 80, the highest speed gear is selected. Until the shift of the auxiliary speed change mechanism 74 from the neutral to the highest speed is completed, the estimated vehicle speed is not calculated in step 108 because it is considered that the shift is in progress, and the estimated vehicle speed is changed after the shift to the highest speed is completed. Is calculated, and the gear position is changed to an appropriate gear based on the calculated estimated vehicle speed.

In this way, the automatic gear shift control device 86 for the vehicle is
Requires the vehicle speed sensor 84 by controlling the control means 88 to switch the engagement state of the auxiliary transmission mechanism 74 of the automatic transmission 70 based on the estimated vehicle speed calculated from the engine speed and the engine output torque. The automatic shift control device can be configured without using the automatic shift control device, and the automatic shift control device having the vehicle speed sensor 84 can be backed up when the vehicle speed sensor fails.

Therefore, this vehicle automatic shift control device 8
6 can control the automatic transmission without the need for the vehicle speed sensor 84, and can achieve cost reduction. In addition, the vehicle automatic shift control device 86 can appropriately perform the shift control of the automatic transmission 70 when the vehicle speed sensor 84 of the automatic shift control device having the vehicle speed sensor 84 is out of order, and can avoid a decrease in driving performance. it can.

Also, the automatic shift control device 86 for this vehicle is used.
Is controlled by the control means 88 to switch the auxiliary transmission mechanism 74 of the automatic transmission 70 to the engagement state of the highest speed when the shift position of the automatic transmission 70 is shifted from the non-forward traveling position to the forward traveling position. By doing so, it is possible to prevent the low speed side shift stage from being held in the engaged state regardless of the vehicle speed to be shifted up.

Therefore, the automatic shift control device 8 for this vehicle is
6 can apply the engine brake without causing the rapid deceleration of the vehicle and the excessive rotation of the engine 2. Further, the automatic gear shift control device 86 for a vehicle can reduce restrictions relating to gear shift such as a gear shift point as compared with an automatic gear shift control device based on engine speed and throttle opening.

Further, the automatic shift control device 86 for this vehicle
The control means 88 controls the shift point of upshifting when the auxiliary transmission mechanism 74 of the automatic transmission 70 is in the engaged state of the shift stage having the one-way clutch, as shown in FIG. Is set in the area.

As shown in FIG. 6, by setting the shift point from the first gear to the engaged state of the second gear in the region where the engine 2 is in the driving state, the first gear having the one-way clutch is formed. It is possible to switch to the engagement state of the second speed gear before the neutral state is established by the one-way clutch.

Alternatively, when the engine 2 is shifted to the non-driving state in the engagement state of the first gear, the setting state is changed to the engagement state of the second gear.
It is possible to switch to the engagement state of the second speed shift stage before the first speed shift stage having the one-way clutch becomes the neutral state by the one-way clutch.

As a result, it is possible to eliminate the inconvenience that the vehicle speed cannot be estimated in the region where the engine 2 is in the non-driving state at the first speed, and the positive driving force is always applied.
It is possible to shift from the high speed shift stage to the engagement state of the second speed shift stage, and it is possible to avoid a state where the engine brake is not effective.

In the above-described embodiment, when the shift position of the automatic transmission 70 is shifted from the non-forward drive position to the forward drive position, the auxiliary transmission mechanism 74 of the automatic transmission 70 is set to the engagement state at the highest speed. However, when the shift position of the automatic transmission 70 is shifted to the non-forward drive position, the vehicle speed at which the auxiliary transmission mechanism 74 of the automatic transmission 70 is switched to the engaged state of the highest speed gear stage. It can also be set to.

This control will be described with reference to the flowchart of FIG.

When the control is started (step 200), the engine speed Ne is compared with the engine stop determination speed NeS set to be equal to or lower than the idle speed (Ne <Ne.
S), and it is determined whether the engine 2 is stopped (step 202).

If the judgment (step 202) is YES (when the engine 2 is stopped), it is judged as fail safe.
The shift process for switching the auxiliary transmission mechanism 74 to the engaged state at the highest speed is performed (step 204), and the process ends (step 216). In the gear shift process (step 204), the output is switched to the first and second solenoid valves 78 and 80 to switch to the highest gear. Until the shift of the auxiliary speed change mechanism 74 from the neutral to the highest speed is completed, the estimated vehicle speed is not calculated in step 210 because it is considered that the shift is in progress, and the estimated vehicle speed is changed after the shift to the highest speed is completed. Is calculated, and the gear position is changed to an appropriate gear based on the calculated estimated vehicle speed.

If the judgment (step 202) is YES (when the engine 2 is stopped), it is judged as fail safe.
By performing the process (step 204) of switching the auxiliary speed change mechanism 74 to the engaged state of the highest speed, it is possible to prevent sudden deceleration of the vehicle and excessive rotation of the engine 2.

When the determination (step 202) is NO (when the engine 2 is driven), it is determined whether the shift position of the automatic transmission 70 is the forward drive position (D, 2, L) (step). 206).

If the determination (step 206) is NO, the vehicle speed is set so that the auxiliary speed change mechanism 74 of the automatic transmission 70 switches to the engaged state of the highest speed gear (step 208).

If the determination (step 206) is YES, the estimated vehicle speed is calculated from the engine speed and the engine output torque as described above (step 210).

When the estimated vehicle speed is calculated in the above (step 210), the shift is judged based on this estimated vehicle speed (step 212). That is, the shift is determined from the shift map of the vehicle speed and the throttle opening based on the calculated estimated vehicle speed and the throttle opening.

In this determination (step 212), if the gear shift is not required (the gear is not shifted), the end is reached (step 216). In this determination (step 212),
If a shift is required (shift), shift processing is performed (step 214) and the process ends (step 216).

In this way, the automatic gear shift control device 86 for the vehicle is
Is controlled by the control means 88 to switch the engagement state of the auxiliary transmission mechanism 74 of the automatic transmission 70 based on the estimated vehicle speed calculated from the engine speed and the engine output torque, and the shift position of the automatic transmission 70. Is shifted to the neutral position (N range), which is the non-forward traveling position, the auxiliary transmission mechanism 74 of the automatic transmission 70.
Is set to a vehicle speed that switches to the engaged state of the highest speed gear stage, and when the auxiliary transmission mechanism 74 is shifted from the neutral position (N range) to the drive position (D range) which is the forward traveling position. A shift determination is performed, the maximum speed shift stage (for example, the third speed shift stage) is switched based on this determination, the estimated vehicle speed is calculated after this shift is completed, and an appropriate shift stage is switched based on the calculated estimated vehicle speed.

As a result, the vehicle automatic shift control device 86
Has the same effects as those of the above-described embodiment. That is, the automatic gear shift control device 86 for the vehicle includes the vehicle speed sensor 8
It is possible to control the automatic transmission without requiring 4 and to achieve cost reduction. The automatic transmission 70 is provided when the vehicle speed sensor 84 of the automatic transmission control device having the vehicle speed sensor 84 fails.
It is possible to appropriately perform gear shift control, and to avoid deterioration of driving performance. In addition, this vehicle automatic shift control device 86
Is capable of applying the engine brake without causing a rapid deceleration of the vehicle or an excessive rotation of the engine 2. The restrictions involved can be reduced.

[0082]

As described above, according to the present invention, the automatic gear shift control device for a vehicle has the engagement state of the auxiliary transmission mechanism of the automatic transmission based on the estimated vehicle speed calculated from the engine speed and the engine output torque. The automatic shift control device can be configured without the need for the vehicle speed sensor by performing control so as to switch the vehicle speed, and the automatic shift control device having the vehicle speed sensor can be backed up when the vehicle speed sensor fails.

Therefore, the automatic gear shift control device for a vehicle can control the automatic transmission without the need for the vehicle speed sensor, which can reduce the cost, and the vehicle speed of the automatic gear shift control device having the vehicle speed sensor. It is possible to appropriately control the shift of the automatic transmission when the sensor malfunctions, and to avoid deterioration of driving performance.

Further, this automatic gear shift control device for a vehicle, when the shift position of the automatic transmission is shifted from the non-forward drive position to the forward drive position, sets the auxiliary transmission mechanism of the automatic transmission to the engagement state of the highest speed gear stage. By controlling to switch to, it is possible to prevent the low speed side shift stage from being held in the engaged state regardless of the vehicle speed to be upshifted.

Therefore, the automatic gear shift control device for the vehicle can apply the engine brake without causing the rapid deceleration of the vehicle or the excessive rotation of the engine. Also,
This automatic gear shift control device for a vehicle can reduce restrictions on gear shifts such as gear shift points, as compared with an automatic gear shift control device based on engine speed and throttle opening.

[Brief description of drawings]

FIG. 1 is a control flowchart of an automatic gear shift control device for a vehicle showing an embodiment of the present invention.

FIG. 2 is a flow chart of control when the vehicle speed is set so that the engagement state becomes the engagement state of the highest speed gear stage.

FIG. 3 is a diagram of a torque converter performance curve during driving.

FIG. 4 is a diagram of a table of gear ratio-pump torque coefficient (τ).

FIG. 5 is a system configuration diagram of a vehicle automatic shift control device.

FIG. 6 is a diagram showing shift points depending on vehicle speed and throttle opening.

FIG. 7 is a diagram showing changes in vehicle speed and estimated vehicle speed during downhill traveling from a state in which the throttle valve is fully closed.

[Explanation of symbols]

 2 engine 56 throttle position sensor 68 crank angle sensor 70 automatic transmission 84 vehicle speed sensor 86 vehicle automatic shift control device 88 control means 96 torque sensor

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[Procedure amendment]

[Submission date] November 22, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction content]

[0013]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention controls to switch the engagement state of an auxiliary transmission mechanism of an automatic transmission connected to an engine mounted on a vehicle. In an automatic gear shift control device for a vehicle, a rotation speed detection means for detecting an engine rotation speed of the engine is provided, a torque detection means for detecting an engine output torque of the engine is provided, and the engine rotation speed and the engine output torque are calculated. The auxiliary transmission mechanism of the automatic transmission is controlled based on the estimated vehicle speed to switch the engagement state, and when the shift position of the automatic transmission is shifted from the non-forward traveling position to the forward traveling position, The automatic transmission is controlled in such a manner that the auxiliary transmission mechanism is switched to the engagement state at the highest speed and the engine speed is not input. An auxiliary transmission mechanism, characterized in that a control means for controlling to switch the engagement of the highest speed gear position.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0015

[Correction method] Change

[Correction content]

Further, in this vehicle automatic shift control device, when the shift position of the automatic transmission is shifted from the non-forward traveling position to the forward traveling position by the control means, the auxiliary transmission mechanism of the automatic transmission is set to the highest speed stage. By controlling so as to switch to the engaged state of No. 3, it is possible to prevent the engaged state of the low speed side shift stage from being held regardless of the vehicle speed to be upshifted. The vehicle automatic speed change control device controls the vehicle speed sensor by switching the auxiliary speed change mechanism of the automatic speed changer to the engaged state at the highest speed when the engine speed is not input by the control means. It is possible to prevent downshifting when the engine rotation speed detection means and the engine speed detection means simultaneously fail.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

A distributor 66 is attached to the cylinder head 6. The distributor 66 is provided with a crank angle sensor 68 that detects not only the crank angle but also the engine speed to function as a rotation speed detecting means.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

The control means 88 is a torque detecting means for detecting a shift position of a shift lever (not shown), an electric load switch 92, an air conditioner compressor switch 94, and an engine output torque of the engine 2. The torque sensor 96 is connected.
The engine output torque can also be calculated from the intake air pressure. In this case, the torque sensor 96 is not needed. The shift switch 90 is such that the shift lever is switched at each of the "P", "R", "N", "D", "2", and "L" positions, and outputs a signal at each position.

[Procedure correction 6]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

In this way, the engine 2 mounted on the vehicle
A vehicle automatic transmission control device 8 for controlling to switch the engagement state of the auxiliary transmission mechanism 74 of the automatic transmission 70 connected to the vehicle.
6, a crank angle sensor 68, which is a rotation speed detecting means for detecting the engine speed of the engine 2, and a torque sensor 96, which is a torque detecting means for detecting an engine output torque of the engine 2, are provided. The auxiliary transmission mechanism 74 of the automatic transmission 70 is controlled to be switched based on the estimated vehicle speed calculated according to the estimated vehicle speed, and is automatically set when the shift position of the automatic transmission 70 is shifted from the non-forward traveling position to the forward traveling position. The auxiliary transmission mechanism 74 of the transmission 70 is controlled so as to be switched to the engaged state of the highest speed gear, and the auxiliary transmission mechanism 72 of the automatic transmission 70 is engaged in the highest speed gear when the engine speed is not input. The control means 88 for controlling to switch to the combined state is provided.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0052

[Correction method] Change

[Correction content]

When this fail-safe is not performed, for example, when the means (rotation speed sensor) for detecting the engine speed during traveling is out of order and the input of the engine speed is lost, it is determined that the engine speed is 0 rpm. Then, the estimated vehicle speed becomes 0 km / h, it is determined that the vehicle is downshifted, and the low speed gear is engaged. For this reason, there is a problem that the vehicle is suddenly decelerated and the engine 2 is excessively rotated.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0064

[Correction method] Change

[Correction content]

Also, the automatic shift control device 86 for this vehicle is used.
Is controlled by the control means 88 to switch the auxiliary transmission mechanism 74 of the automatic transmission 70 to the engagement state of the highest speed when the shift position of the automatic transmission 70 is shifted from the non-forward traveling position to the forward traveling position. By doing so, it is possible to prevent the low speed side shift stage from being held in the engaged state regardless of the vehicle speed to be shifted up. Further, the vehicle automatic shift control device 86 controls the control means 88 to switch the auxiliary transmission mechanism 72 of the automatic transmission 70 to the engaged state of the highest speed when the engine speed is not input. As a result, when the vehicle speed sensor 84 and the crank angle sensor 68, which is an engine speed detecting means, simultaneously fail,
It is possible to prevent downshifting.

[Procedure Amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0084

[Correction method] Change

[Correction content]

Further, this automatic gear shift control device for a vehicle, when the shift position of the automatic transmission is shifted from the non-forward drive position to the forward drive position, sets the auxiliary transmission mechanism of the automatic transmission to the engagement state of the highest speed gear stage. By controlling to switch to, it is possible to prevent the low speed side shift stage from being held in the engaged state regardless of the vehicle speed to be upshifted. The vehicle automatic speed change control device controls the vehicle speed sensor by switching the auxiliary speed change mechanism of the automatic speed changer to the engaged state at the highest speed when the engine speed is not input by the control means. It is possible to prevent downshifting when both the engine speed detection means and the engine speed detection means fail at the same time.

Claims (2)

[Claims] 1. An automatic transmission control device for a vehicle, which controls to switch an engagement state of an auxiliary transmission mechanism of an automatic transmission connected to an engine mounted on a vehicle, the rotational speed detecting an engine rotational speed of the engine. A sensor is provided to provide a torque sensor for detecting the engine output torque of the engine, and the engagement state of the auxiliary transmission mechanism of the automatic transmission is switched based on the estimated vehicle speed calculated from the engine speed and the engine output torque. Control means is provided for controlling and controlling the auxiliary transmission mechanism of the automatic transmission to switch to the engaged state of the highest speed when the shift position of the automatic transmission is shifted from the non-forward traveling position to the forward traveling position. An automatic gear shift control device for a vehicle characterized by the above. 2. The control means sets a shift-up shift point in a region where the engine is in a driving state when the auxiliary transmission mechanism of the automatic transmission is in an engaged state of a shift stage having a one-way clutch. The automatic shift control device for a vehicle according to claim 1, wherein: