JPH0634033A - Speed change controller for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent a speed change from being returned to an original speed change stage immediately after an up or down speed change while rapidly performing a necessary speed change in an automatic transmission. CONSTITUTION:A moderate change throttle valve opening degree signal TVOb is produced by moderating a change of a real throttle valve opening degree signal TVOa. A pseudo throttle valve opening degree signal TVO' is produced, which is changed at the time when a deviation between the moderate change throttle valve opening degree signal TVOb and the real throttle valve opening degree signal TVOa is lower than a predetermined value K. Namely, the pseudo throttle valve opening degree signal TVO' is changed when the real throttle valve opening degree signal TVOa becomes stable. In such a state where a speed is returned to the original speed change stage transversing a speed change line after a speed is changed up or down transversely to the speed change line according to a change of the throttle valve opening degree, as viewed in Figure showing the speed change line, a speed change is controlled by using the pseudo throttle valve opening degree signal TVO' on the basis of the speed change line.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for an automatic transmission, and more particularly to an improvement of a shift control device which holds a shift speed at a low speed during a deceleration operation so that an engine brake works effectively.

[0002]

2. Description of the Related Art The applicant of the present application has proposed a shift control device for an automatic transmission of this type, which is disclosed in Japanese Patent Laid-Open No. 2-38747. For example, in the shift line diagram of FIG. 2, this part extends a portion of the 3 → 4 up shift line near the fully closed throttle valve to around 75 km / h on the high speed side, and the driver indicates by a symbol β in the figure. When the throttle valve opening is closed to decelerate from the third forward speed range,
Even if the 3rd to 4th upshift line is crossed at the predetermined throttle valve opening, the shift up to the fourth speed is delayed for the set time, and the throttle valve opening is fully closed before the set time elapses. If it enters the extension region of the low speed stage to the high speed side, the shift up to the 4th speed is prohibited, the 3rd speed is maintained, and the effect of the engine braking is effectively exhibited.

[0003]

However, in the above-mentioned proposal, the low speed stage can be maintained during deceleration operation with the throttle valve opening fully closed, but the opening is maintained after the throttle valve opening is slightly closed. In this case, as shown by the symbol α in the figure, even if the 3 → 4 upshift line is crossed, the upshift to the 4th speed is not immediately performed, and the driver is delayed until the set time elapses, which causes the driver to change. There is a feeling of sympathy.

The present invention has been made in view of the above circumstances, and an object of the present invention is to early shift if a driver exceeds a predetermined upshift line when the throttle valve opening is slightly closed and maintained. During deceleration operation in which the throttle valve opening is fully closed and the throttle valve opening is fully closed, the low speed stage is held without performing the shift up and the engine brake is effectively operated.

[0005]

In order to achieve the above object, the present invention has a structure in which a stable state of an engine load is detected, and after a change in the engine load, a shift is started when the engine load becomes stable.

That is, a concrete solution means of the invention according to claim 1 is a speed change means for switching a power transmission path of a speed change mechanism, and a time when a speed change should be made in accordance with a change in engine load on a speed change diagram stored in advance. And a shift-time detecting means for detecting a shift time at which it can be predicted that the original shift stage may be restored after the shift, a load stable state detecting means for detecting a stable state of an engine load, and the shift detecting means. The control means for controlling the speed changing means based on the speed change diagram is provided after waiting for the stable state of the engine load to be detected by the load stable state detecting means during the speed change detected by.

According to the second aspect of the present invention, the load steady state detecting means of the first aspect of the present invention is specified so that the change of the actual engine load signal is moderated. A pseudo engine load signal that changes when the deviation from the load signal is less than a set value is created, and the control means is configured to control the speed changing means based on the pseudo engine load signal.

Further, in the invention according to claim 3, in the invention according to claim 1 or 2, the low speed region near the engine no-load region of a predetermined shift line is extended to the high speed side as a shift diagram. The shift detection means is configured to detect a shift time that crosses the shift pattern extended to the high speed side in accordance with a change in engine load.

In addition, in the invention described in claim 4, in the invention described in claim 3, the control means is specified, and when the no-load signal of the engine is inputted, the speed change means is held so as to maintain the low speed stage. Consists of things to control.

Further, in the invention according to claim 5, in the invention according to claim 3 or 4, the control means is specified to another one, and only when the brake pedal is depressed, the engine is unloaded. The transmission means is controlled so that the low speed stage is maintained by inputting a signal.

Further, in the invention according to claim 6, in the invention according to claim 3 or 4, the control means is specified to another one, and the deviation between the slowly changing engine load signal and the actual engine load signal is determined. Only when is above the set value,
It is configured to control the speed changing means so as to maintain the low speed stage by inputting the no-load signal of the engine.

In addition, in the invention described in claim 7, in the invention described in claim 3 or 4, the control means is specified to another one, and when the deceleration degree of the vehicle is less than the set value. As far as possible, the speed change means is controlled so as to maintain the low speed stage by the input of the no-load signal of the engine.

[0013]

With the above construction, in the inventions of claims 1 and 3, the shift control is performed after waiting for the stable state of the engine load, so that the shift operation is prevented when the engine load changes, and the predetermined speed is maintained. The frequent shift operation of down-shifting or up-shifting to the original shift stage after the up-shifting or down-shifting from the shift stage is eliminated. Moreover, when the change range of the engine load is small, such as when the throttle valve opening is halfway closed, the change of the engine load stabilizes early, so that the required gear shift is performed in a short time.

According to the second aspect of the present invention, when the engine load greatly changes and becomes stable, the value of the slowly changing engine load signal approaches the value of the actual engine load signal after a relatively long time. Since it takes time until the deviation between the two signals becomes less than the set value, the pseudo engine load signal changes after a relatively long time has elapsed. On the other hand, when the change in engine load is small, the value of the slowly changing engine load signal quickly approaches the value of the actual engine load signal, and the deviation between both signals becomes less than the set value in a short time. The signal changes after a short time. Therefore, during a deceleration operation in which the throttle valve opening is largely operated to be fully closed, the pseudo engine load signal does not change during the closing, so gear shifting is not performed, and when the pseudo engine load changes, that is, the throttle valve opening is fully opened. When the closed state is stabilized, the gear shift is performed based on the shift diagram, and the operation of shifting to the original gear after the up or down shift based on crossing the shift line is prevented. Moreover, during deceleration operation in which the throttle valve is closed halfway, the pseudo engine load signal changes early, and the necessary gear shift is performed in a short time.

Further, according to the invention described in claim 4, since the low speed stage is held by the control means when the no-load signal of the engine is inputted, that is, during the deceleration operation, the engine brake works effectively.

In addition, according to the inventions of claim 5, claim 6, and claim 7, even when the engine no-load signal is input, when the brake pedal is stepped on, a slowly changing engine load signal and actual The control means keeps the low speed stage only during a sudden deceleration operation in which the deviation from the engine load signal exceeds the set value or when the vehicle deceleration is less than the set value and stronger deceleration is required. The engine brake will effectively operate according to the deceleration request.

[0017]

As described above, according to the shift control device for an automatic transmission of the first and third aspects of the invention, the stable state of the engine load is detected and the shift based on the shift diagram is performed. Since the control is performed, it is possible to prevent frequent shifts by preventing the shift operation that immediately returns to the original gear after an up or down shift by continuously crossing the shift line, and at the same time perform necessary shifts quickly. It is possible.

Further, according to the second aspect of the present invention, the delay time until the shift control is started can be automatically set according to the degree of change of the engine load, so that the original shift is immediately performed after the up or down shift. It is possible to surely prevent the gear shifting operation to return to the gear, and to perform the necessary gear shifting operation in a short time.

Further, according to the inventions of claim 4, claim 5, claim 6, and claim 7, since the low speed stage can be held and controlled in response to the driver's deceleration request, the engine brake is applied only when necessary. It can act effectively, and the driving performance can be improved.

[0020]

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

In FIG. 1, reference numeral 1 denotes an engine, and an intake passage 1a of the engine 1 is provided with a throttle valve 1b for adjusting an intake air amount. 2 is the engine 1
And an automatic transmission 2 arranged behind the automatic transmission 2, wherein the automatic transmission 2 includes a torque converter 3 with a lock-up mechanism,
For example, the shift mechanism 4 has four forward gears and one reverse gear. Below the speed change mechanism 4, three electromagnetic solenoid valves 5 for speed change control and an electromagnetic solenoid valve 6 for controlling the fastening force of the lock-up mechanism are arranged. The transmission means 7 for switching the power transmission path of the transmission mechanism 4 is configured. A propeller shaft 8 is connected to the rear portion of the transmission mechanism 4, and the propeller shaft 8
The power is transmitted to the left and right drive wheels via the.

Further, 10 is a controller having a CPU inside, 11 is an opening sensor for detecting the opening of the throttle valve 1b of the engine 1, 12 is a vehicle speed sensor for detecting the vehicle speed, and 13 is an automatic transmission 2. A gear speed sensor for detecting the gear position that is being operated, 14 is an idle switch that detects the fully closed state of the throttle valve 1b and is turned on, 15 is a rotation speed sensor that detects the engine speed, and 16 is a brake applied by the driver. A brake switch which is turned on when the pedal is depressed, and signals of these sensors and switches are inputted to the controller 10, and the controller 10 controls the shift stage and the lockup mechanism based on these signals. This is a configuration for controlling the electromagnetic solenoid valves 5 and 6.

The shift diagram shown in FIG. 2 is stored in advance inside the controller 10. In the shift diagram, the horizontal axis represents vehicle speed, the vertical axis represents throttle valve opening, that is, engine load, and upshift lines indicated by solid lines 1 → 2, 2 → 3, 3 → 4 and 3 ← 4, 2 ← 3, 1 ← 2, and each down shift line indicated by a broken line. Among them, the 3 → 4 up shift line has an engine no load, that is, a low speed region near zero of the throttle valve opening is on the high vehicle speed side. It has been extended to around 75 Km / h, and for example, as shown by the symbol β in the figure, the throttle valve opening is fully closed from the range of the third forward speed to enter the extension range. It is configured to hold the third speed and to effectively act the engine brake (hereinafter,
This operation is called the auto emblem function).

Then, as shown in FIG. 3, the controller 10 uses a broken line in the figure which shows a gentle change in response to the actual throttle valve opening signal TVOa shown by the solid line in the figure from the opening sensor 11. Slow change throttle valve opening signal T shown
In addition to having the function of creating VOb, when the actual throttle valve opening signal TVOa changes, both signals TVOa,
The value is updated when the deviation of TVOb becomes a small value and becomes less than the set value k (indicated by symbol A in the figure) with the passage of time, and the pseudo throttle valve opening signal TV shown by the one-dot chain line in the figure
It has a function as a load stable state detecting means 17 which creates O ′ and detects the stable state of the engine load.
The load stable state detecting means 17 may be configured to detect the rate of change of the throttle valve opening.

Next, FIG. 4 shows the configuration of the shift control by the controller 10. In the figure, 20 is a 3 → 4 upshift standby circuit, 30 is an auto emblem circuit, and 40 is an auto emblem cancel determination circuit. The 3 → 4 up shift standby circuit 20 includes an OR circuit 21 and an AND circuit 22. The OR circuit 21 determines whether the pseudo throttle valve opening TVO ′ (i) or TVO ′ (i) at this time or the previous time on the shift diagram of FIG.
When -1) is in a region other than the fourth forward speed, "1" is output. When the vehicle speed is in the vehicle speed range of 75 km / h or less where the auto-embracing function is required and the vehicle speed is in the fourth speed range on the shift diagram when judged by the actual throttle valve opening TVOa. , When the "1" output is received from the OR circuit 21, it outputs "1" (outputs an upshift standby signal to the fourth speed), and otherwise outputs "0" (fourth speed). It does not output the upshift permission signal to). The "1" output of the AND circuit 22 is release-controlled after the set time.

Therefore, the above 3 → 4 upshift standby circuit 2
0, the upshift to the fourth forward speed across the 3 → 4 upshift line is detected in accordance with the change in the throttle valve opening, which is the engine load, on the shift diagram of FIG. 2 stored in advance. At the time of gear shifting, at the time of gear shifting, it is predicted that after the gear shifting, the throttle valve opening may be fully closed to enter an extension region near the throttle valve zero opening of the 3 → 4 up gear shift line and the gear may return to the original gear stage. The detection means 23 is configured.

Further, the auto-embracing circuit 30 includes the first, second, third and fourth AND circuits 31 to 34, an OR circuit 35, and a holding circuit 3 including a flip-flop circuit.
6 and 6. When the first AND circuit 31 receives the ON signal of the idle switch 14 at the time of receiving the up shift standby signal (“1” output) of the AND circuit 22 of the 3 → 4 up shift standby circuit 20 to the fourth speed, 1 ”output.
The second AND circuit 32 receives the ON signal of the idle switch 14 at the time of selecting the fourth forward speed in a vehicle speed of 75 km / h or less where the auto-embracing function is required, that is, when the auto-embracing function is activated. Outputs "1" when the required basic condition is satisfied. The third AND circuit 33, when the second AND circuit 32 outputs "1", slowly changes the throttle valve opening signal TVOb and the actual throttle valve opening signal TVO.
Deviation from a is greater than or equal to the set value X (TVOb-TVOa ≧ X)
When, that is, when the throttle valve opening changes rapidly in the closing direction, "1" is output. Furthermore, when the second AND circuit 32 outputs "1", the fourth AND circuit 34 turns on the brake switch 16 and sets the previous value V (i-1) and the current value V (i) of the vehicle speed. When the deviation is lower than the set value f (V) (f (V) is a function of the vehicle speed V), the deceleration degree is low, and the output is "1". In addition, the OR circuit 35 receives the "1" output of the first, third, or fourth AND circuit 31, 33, 34, and the holding circuit 36 outputs the "1" output of the OR circuit 35. It is received by the S terminal and set, and the Q terminal outputs "1" (outputs the third speed hold signal).

Therefore, the above 3 → 4 up shift standby circuit 2
With the OR circuit 21 and the auto emblem circuit 30 of 0,
When the throttle valve opening actually crosses the 3 → 4 up shift line on the shift diagram and the 3 → 4 up shift standby circuit 20 detects a 3 → 4 up shift, the pseudo engine of the load stable state detecting means 17 is detected. At the time when the load signal TVO 'changes, that is, after waiting for the stable state of the engine load to be detected, the "1" output from the AND circuit 22 (the output of the upshift standby signal to the fourth speed) is stopped. The output of "0" controls the electromagnetic solenoid valves 5 and 6 so as to perform the shift based on the shift diagram of FIG. 2, and the throttle valve opening degree changes when the vehicle travels at the fourth speed when the vehicle speed is 75 km / h or less. If it is fully closed, there is a large change in the closing direction of the throttle valve TVOb-
When TVOa ≧ X, or when the deceleration rate is low V (i-1) -V
(i) When the driver depresses the brake pedal under the condition of ≤f (v), the third speed holding signal is output from the holding circuit 36 (becomes "1" output), and the third speed is output. The control means 37 for controlling so as to hold

Further, the automatic emblem release determination circuit 40
Has a function of determining whether to release the third-speed holding control by the auto-embrake circuit 30, and the release is performed for each operating region divided according to the throttle valve opening and the vehicle speed as shown in FIG. Be seen.

In the section of the operation area shown in FIG. 5,
The region indicated by the symbol is a region where the throttle valve opening on the 3 → 4 upshift line exceeds the extension region near zero and in which constant speed running is possible at the third speed selected in the extension region. This is an operating area below the constant speed running line indicated by the alternate long and short dash line. Further, the regions indicated by the symbols are the high vehicle speed side regions exceeding the 3 → 4 up shift line in the operating region of the first set engine load or more corresponding to the third speed constant speed running line indicated by the one-dot chain line, and in the figure. A fourth speed constant speed running line shown by a two-dot chain line, a third speed constant speed running line shown by the one-dot chain line, and a 3 → 4 up shift line,
An operating region surrounded by 3 ← 4 downshift lines (this region is particularly indicated by a symbol '), and 3 → 4 upshift lines are used as a second set engine load value that changes according to the vehicle speed. Furthermore, the operating area indicated by the shaded symbols is 3
→ In the low vehicle speed range below the 4th upshift line, the high load range above the 4th constant speed running line indicated by the chain double-dashed line, and 3 ← 4
It is a low vehicle speed region below the downshift line. Here, the controller 10 detects that the operating state has shifted from the above region to a region other than the region based on the outputs of the opening sensor 11 and the vehicle speed sensor 12.

The automatic emblem cancellation determination circuit 40 is
When the controller 10 detects an operating state in which the operating state shifts from the above region to a region other than the above region,
The shift line of the shift diagram of FIG. 2 functions separately as a control switching unit that switches the shift control for each operating region of FIG. 5, which is divided separately from the shift line. The configuration of the holding circuit 41 is a flip-flop circuit. A first AND circuit 42. The holding circuit 41 is a circuit that holds the third speed holding signal of the auto-embracing circuit 30, and includes the first AND circuit 4
Reference numeral 2 has a function of outputting a cancellation signal for canceling the output of the third speed holding signal, and can output the cancellation signal only when the holding circuit 41 receives the third speed holding signal. Further, a signal obtained by inverting the output when the current operating state is in the area of the map of FIG. 5 is input to the first AND circuit 42, and when the operating state is in the area, the release signal is output. It is a prohibited structure.

Further, the automatic emblem release determination circuit 40
Is an OR circuit 43 and second and third AND circuits 44, 4
5 and a holding circuit 46. The OR circuit 43
Inputs the output when the current operating state is in the area of the map of FIG. 5, inputs the output to the first AND circuit 42, and enables the output of the release signal. The second AND circuit 44 outputs "1" when the previous and the last-previous operation states are in the region of the map of FIG. 5, and the holding circuit 46 holds the output of the second AND circuit 44. The third AND circuit 45 outputs the difference between the output of the holding circuit 46 and the difference between the previous value and the current value of the pseudo throttle valve opening TVO.
'(I-1) -TVO' (i) is the output when it is equal to or greater than the set value Y near zero, that is, the output when it is decelerated slightly to shift to steady operation after acceleration and is stable. "1" output, and the "1" output is input to the first AND circuit 42 via the OR circuit 43 to enable the release signal.

Further, the OR circuit 43 receives an inversion signal of the output when the current driving state is in the region of FIG. 5 through the timer 47 after a set time, and the current vehicle speed V (i) is shown in FIG. Vehicle speed value V (MEM
When the value is equal to or greater than the value obtained by adding the small value Z to (O) (V (i) ≥ V (MEM
O) + Z) output, that is, a vehicle speed increase signal is input, and if the current driving state is out of the range shown in FIG. 5, a release signal can be output after a set time or when the vehicle speed increases. .

In addition, the automatic emblem cancellation determination circuit 40
Has a fourth AND circuit 48. The fourth AND circuit 48 receives the release signal of the first AND circuit 41 and outputs the output when there is a third speed holding signal last time, the output when there is no third speed holding signal this time, and the current output. 5 is output when the operating state of FIG. 5 is in the region of FIG. 5 (the fourth speed shift-up signal is output), and when the release signal is output, the regions and regions of FIG. In the case of, the third speed is held as the output of "0", while in the region of FIG. 5 when the release signal is output, the fourth speed shift-up signal is output as the output of "1".

Further, the automatic emblem release determination circuit 40
Has a fifth AND circuit 49, and the AND circuit 49
Is the output of the timer 50 that delays the output when the current operating state is in the lock-up region of FIG. 2 by the set time, and the “1” output (fourth speed shift-up signal) of the fourth AND circuit 48. In response, after waiting for the set time after the upshift control to the 4th speed, the output becomes "1" (a lockup signal is output), and the solenoid solenoid valve 6 is operated by the lockup signal. The lock-up mechanism is fastened.

Therefore, in the above-described embodiment, the driver changes the throttle valve opening from the time when the vehicle is in the third speed range below the vehicle speed of 75 km / h as indicated by the symbol β in the shift diagram of FIG. When fully closed, as shown in FIG. 6, when the actual throttle valve opening TVOa exceeds the 3 → 4 up shift line at the point of symbol B, the AND circuit 22 of the 3 → 4 up shift standby circuit 20 shifts to the first position. 4th speed up standby signal (“1” output)
Is output and the shift up to the fourth speed is awaited. After that, when the idle switch 14 is turned on with the actual closing of the throttle valve opening TVOa, the first AND circuit 31 of the auto-embracing circuit 30 outputs “1” at this time, and the Q terminal of the holding circuit 36 becomes Since the third speed holding signal is output (the output is “1”), the automatic transmission 2 does not shift up to the fourth speed and holds the third speed. As a result, the engine brake acts effectively and the deceleration performance of the vehicle is effectively exhibited. The actual throttle valve opening TVOa and the slowly changing throttle valve opening signal TVOb
At the time when the deviation from and becomes less than the set value k, the OR circuit 21 of the 3 → 4 up shift standby circuit 20 inverts to the “0” output, and the output of the fourth speed up standby signal from the AND circuit 22 (“ However, since the fourth speed-up standby signal is held by the holding circuit 36, no trouble occurs.

On the other hand, when the driver only slightly closes the throttle valve opening and crosses the 3 → 4 up shift line as indicated by the symbol α in the shift diagram of FIG. 2, the same as above. 3 →
Although the AND circuit 22 of the 4-up shift standby circuit 20 outputs the fourth speed-up standby signal (becomes "1" output), the idle switch 14 does not turn ON, so the first AND circuit 31 of the auto-embrake circuit 30. Does not output "1", and the holding circuit 36 does not output the third speed holding signal. In this case, when the deviation between the actual throttle valve opening TVOa and the slowly changing throttle valve opening signal TVOb reaches the set value k, the output of the fourth speed up standby signal is stopped. Shift up to speed is performed. Here, the output period of the fourth speed up standby signal is short.
That is, since the change in the actual throttle valve opening TVOa is small, the slowly changing throttle valve opening TVOb approaches the vicinity of the actual opening TVOa in a short time, and the deviation between the two openings becomes less than the set value k in a short time. Therefore, when the driver slightly closes the throttle valve opening, the upshift to the fourth speed is performed in a relatively short time, so that the driver does not feel discomfort.

Further, when the vehicle is running at the fourth forward speed and the vehicle speed is less than 75 km / h and the driver fully closes the throttle valve opening, as shown in FIG. The second AND circuit 32 of the circuit 30 outputs "1". In this case, when the deviation between the slowly changing throttle valve opening TVOb and the actual opening TVOa is equal to or larger than the set value X, that is, when the driver's closing operation of the throttle valve opening is quick, the third AND circuit 33 sets " 1 "output and the Q terminal of the holding circuit 36 outputs the third speed holding signal (" 1 "output), so that the automatic transmission 2 shifts down from the fourth speed to the third speed. Therefore, since the downshift from the fourth speed to the third speed is performed only when the driver demands a fast deceleration for closing the throttle valve opening, downshift control that matches the driver's deceleration request can be performed, and the automatic engine braking can be performed. The number of shifts can be appropriately limited as compared with the case where the downshift by the function is always performed.

Further, as shown in FIG. 9, the vehicle speed is 75 km.
If the driver fully closes the throttle valve opening at the fourth forward speed when traveling downhill in a condition of less than / h, the second AND circuit 32 of the auto-embrake circuit 30 outputs "1". Become. In this case, the difference V between the previous value and the current value of the vehicle speed
(i-1) When -V (i) is less than the set value f (v), that is, when the deceleration of the vehicle speed on the downhill is low and the driver depresses the brake pedal, the brake switch is turned on. At this time, the fourth AND circuit 34 of the auto emblem circuit 30 outputs "1", and the Q terminal of the holding circuit 36 outputs the third speed holding signal. At this point, the automatic transmission 2 therefore outputs the fourth speed. Downshifts to third speed. Therefore, even when the throttle valve opening is fully closed, the downshift to the third forward speed is always performed only when the driver requests the deceleration when the driver depresses the brake pedal to increase the deceleration when traveling downhill. As compared with the case where the downshift is performed by the auto-embrake function when the throttle valve opening is fully closed, the downshift control that meets the driver's deceleration request can be performed, and the number of shifts can be appropriately limited.

[Brief description of drawings]

FIG. 1 is an overall schematic configuration diagram.

FIG. 2 is a diagram showing a shift diagram.

FIG. 3 is an explanatory diagram of a pseudo engine load signal.

FIG. 4 is a diagram showing a specific circuit of an automatic engine shake control circuit.

FIG. 5 is an explanatory diagram of an operation region divided to cancel the automatic embrace function.

FIG. 6 is an operation explanatory diagram during deceleration operation with the throttle valve opening fully closed.

FIG. 7 is an operation explanatory diagram during deceleration operation with the throttle valve opening half closed.

FIG. 8 is an operation explanatory diagram during deceleration operation in which a throttle valve opening is rapidly closed.

FIG. 9 is an operation explanatory diagram during deceleration operation in which a brake pedal is depressed.

[Explanation of symbols]

 4 Gear change mechanism 5, 6 Electromagnetic solenoid valve 7 Gear change means 10 Controller 17 Load stable state detection means 20 3 → 4 up gear change standby circuit 23 Gear change detection means 30 Auto emble circuit 37 Control means

Front Page Continuation (72) Inventor Kei Takashi, 3-1, Shinchi Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (72) In-house Takayuki Sakai, 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Corporation

Claims (7)

[Claims] 1. A speed change means for switching a power transmission path of a speed change mechanism, and a time when a speed change should be made in accordance with a change in an engine load on a speed change diagram stored in advance and the speed is returned to the original speed after the speed change. There is a shift time detection means for detecting a shift time that can be predicted, a load stable state detection means for detecting a stable state of an engine load, and a load stable state detection means for a shift time detected by the shift time detection means. A shift control device for an automatic transmission, comprising: a control means that waits until a stable state of an engine load is detected and controls the shift means based on the shift diagram. 2. The load stable state detecting means creates a pseudo engine load signal that changes when the deviation between the slowly changing engine load signal and the actual engine load signal, which is made by gradually changing the actual engine load signal, is less than a set value. Is what
The shift control device for an automatic transmission according to claim 1, wherein the control means controls the shift means based on the pseudo engine load signal. 3. The shift diagram is formed in a shift pattern in which a low speed region near a no-load region of a predetermined shift line is extended to a high speed side, and the shift detecting means responds to a change in engine load. The shift control device for an automatic transmission according to claim 1 or 2, wherein a shift time across a shift pattern extended to the high speed side is detected. 4. The shift control device for an automatic transmission according to claim 3, wherein the control means controls the transmission means so as to maintain the low speed stage when an engine no-load signal is input. 5. The control means controls the speed changing means so as to maintain the low speed stage by inputting a no-load signal of the engine only when the brake pedal is depressed. Shift control device for automatic transmission. 6. The control means controls the speed changing means to hold the low speed stage by inputting the no-load signal of the engine only when the deviation between the slowly changing engine load signal and the actual engine load signal becomes equal to or more than a set value. 5. The shift control device for an automatic transmission according to claim 3, wherein the shift control device controls the shift. 7. The control means controls the transmission means so as to maintain a low speed stage by inputting a no-load signal from the engine only when the deceleration degree of the vehicle is less than a set value. A shift control device for an automatic transmission according to claim 4.