JP2000266173A - Speed change control device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speed change control device for automatic transmissions which realizes a smooth speed change performance by reducing the torque reducing depth in a torque phase, suppressing a thrust torque, and making the torque phase time shorter, by preventing the generation of an engine racing securely in a speed changing time. SOLUTION: A turbine rotation frequency deflection operation means e to operate the difference between the detecting value and the inferring value of the turbine rotation frequency; a release controller f1 which reduces the releasing pressure of the first fastening element a to a specific pressure adding a surprass pressure to a fastening maintaining pressure, so as to make wait as in the specific pressure, until the turbine rotation frequency deflection operation means is made to a setting pressure when a speed change starting instruction is put out; and a before change speed gear stage phase control means f by a fastening pressure controller f2 which carries out the middle operation control to raise the fastening pressure of the second fastening element b from a return proper pressure gradually at a specific inclination until a return rotation frequency deflection is made to the set value, when the speed change instruction is put out; are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a shift control device of an automatic transmission for controlling a release hydraulic pressure and an engagement hydraulic pressure in a transition period of a shift change.

[0002]

2. Description of the Related Art In a one-way clutchless (hereinafter, OWC-less) automatic transmission aiming at reducing the weight and size of the automatic transmission, the shifting timing at the time of shifting is set to O.
Since the WC cannot be used, it is important to control the switching timing of the fastening element on the fastening side and the fastening element on the release side.

On the other hand, as a conventional shift control device of an automatic transmission aiming at OWC-less, for example, Japanese Unexamined Patent Publication No.
The thing described in 211,760 is known.

This conventional publication aims at realizing a smooth shift with good shift feeling with little shift shock at the time of an OWC-less upshift, and an amount of air blowing to suppress the turbine rotation to a predetermined amount of air blowing. A technique for controlling the release pressure of a fastening element released while monitoring the pressure is described.

[0005]

However, in the above-described conventional shift control device for an automatic transmission, as shown in FIG. 11, the amount of airflow at the turbine speed Nt is detected, and the detected value of the amount of airflow is detected. When the engine speed exceeds a predetermined amount, the release-side capacity increase control is performed. As a result, torque pulling or torque thrust occurs in the torque waveform during the torque phase, and the torque phase time (pulling time) becomes longer. There is a problem that is worse.

[0006] When the engine is idling, the engine speed should be reduced during an upshift, but the engine speed is increased, which gives the driver an uncomfortable feeling (impression of a failure). Blowing generates heat on the release-side fastening element, thereby deteriorating durability.

In addition, this conventional apparatus is a control which allows the occurrence of an idling, and cannot solve the above-mentioned problem as long as the idling occurs at the time of shifting.

The problem to be solved by the present invention is to reduce the torque pulling depth in the torque phase, suppress thrust torque, and reduce the torque phase time by reliably preventing the occurrence of engine idling during gear shifting. And shorten
It is an object of the present invention to provide a shift control device for an automatic transmission that realizes a smooth shift performance.

[0009]

According to the first aspect of the present invention,
As shown in the claim correspondence diagram of FIG. 1, when the shift start command is output, the first engagement element a that has been engaged in the gear before the shift without intervening the one-way clutch.
In a shift control device for an automatic transmission that achieves a gear after shifting by changing over by releasing the released second fastening element b, a turbine speed detecting means c for detecting a turbine speed, Estimated turbine speed calculating means d for calculating an estimated turbine speed following the progress of the shift based on the turbine speed at the time when the shift start command is output, the turbine rotation acceleration, and the elapsed time after the start of the shift.
A turbine rotation speed deviation calculating means e for calculating a turbine rotation speed deviation between the turbine rotation speed detection value and the turbine rotation speed estimation value, and until the turbine rotation speed deviation reaches a set value when a shift start command is output. A release pressure control unit f1 for lowering the release pressure of the first engagement element a to a constant pressure obtained by adding a margin pressure to the engagement holding pressure and keeping the constant pressure at a standby state; A pre-shift gear stage phase control means f by an engagement pressure control unit f2 for performing an indentation control for gradually increasing the engagement pressure of the second engagement element b from a return equivalent pressure at a predetermined gradient until the deviation reaches a set value; From the point in time when the rotational speed deviation has reached the set value, the release-side hydraulic pressure of the first engagement element a is decreased at a predetermined gradient, and the engagement-side hydraulic pressure of the second engagement element b is increased at a predetermined gradient to perform a shift change. Characterized in that it comprises a Rukufezu control means g, the.

According to a second aspect of the present invention, in the shift control device for an automatic transmission according to the first aspect, the hydraulic pressure contributing to the generation of the transmission torque of the fastening element is set to “effective hydraulic pressure” and remains engaged during gear shifting. When the transmission torque of any one of the fastening element to be released, the fastening element to be released, and the fastening element to be fastened is set to zero, the rotation ratio of each rotating member is just changed by the transmission torque of one of the remaining fastening elements. When not kept, the transmission torque of this one fastening element is referred to as “sharing torque” with respect to the transmission input torque,
When the hydraulic pressure effective to generate the "sharing torque" is defined as "sharing pressure" and the ratio of the effective hydraulic pressure to the sharing pressure in one fastening element is defined as "sharing ratio", the first torque phase control means g Is characterized in that the sharing pressure is set such that the value obtained by adding the engagement side torque sharing ratio and the release side torque sharing ratio is 1.0 or more to perform the shift change.

According to a third aspect of the present invention, as shown in the claim correspondence diagram of FIG. 1, in the shift control device for an automatic transmission according to the first or second aspect, an engagement side hydraulic pressure of the second engagement element b is provided. Upper limit shelf pressure setting means h for setting an upper limit shelf pressure exceeding the engagement holding capacity, output shaft speed detecting means i for detecting the output shaft speed of the automatic transmission, and turbine speed for the output shaft speed detection value When the gear change calculating means j for calculating the gear ratio, which is the ratio of the detected values, and the shift speed change time by the first torque phase control means g are completed, the first
Inertia phase control means k for raising the release-side hydraulic pressure of the fastening element a as the drain and raising the engagement-side hydraulic pressure of the second fastening element b to the set upper-limit shelf pressure, and the engagement-side hydraulic pressure of the second fastening element b Second torque phase control means m for maintaining the upper limit shelf pressure as it is when the calculated gear ratio becomes the shift completion gear ratio when the calculated gear ratio reaches the shift completion gear ratio, and the second engagement element when the calculated gear ratio becomes the shift complete gear ratio. And a post-shift gear stage phase control means n for increasing the engagement side hydraulic pressure from the upper limit shelf pressure to the line pressure.

According to a fourth aspect of the present invention, in the shift control device for an automatic transmission according to any one of the first to third aspects, the hydraulic control means of the first engagement element and the hydraulic control means of the second engagement element are controlled by a drive. It is characterized in that means for independently and electronically controlling the hydraulic pressure are used based on the range pressure as a base pressure.

[0013]

(Embodiment 1) Embodiment 1 is a shift control device for an automatic transmission according to the first to fourth aspects of the present invention.

First, the configuration will be described.

FIG. 2 is a diagram showing an example of a gear train of an automatic transmission to which the transmission control device of the first embodiment is applied.
Is the engine output shaft, I is the transmission input shaft, O
Is a transmission output shaft, and the engine output shaft E
A torque converter T / C is interposed between the transmission input shaft I and the transmission input shaft I, and a first planetary gear set G is disposed between the transmission input shaft I and the transmission output shaft O.
1 and a second planetary gear set G2 are interposed. The first planetary gear set G1 is a simple planetary gear set including a first pinion P1, a first carrier C1, a first sun gear S1, and a first ring gear R1, and the second planetary gear set G2 is a second pinion P2.
This is a simple planetary gear set including a second carrier C2, a second sun gear S2, and a second ring gear R2.

The transmission input shaft I is directly connected to the second sun gear S2.
A reverse clutch R / C is provided in the middle of a member connecting the first sun gear S1 and the first sun gear S1, and a 2-4 brake 2-4B for fixing this member to the case is provided. Transmission input shaft I and first carrier C
A high clutch H / C is provided in the middle of the member connecting the first clutch and the first clutch. First carrier C1 and second ring gear R
A low clutch L / C is provided in the middle of the member connecting the second and second, and a low & reverse brake L & R / B for fixing this member to the case is provided.
A one-way clutch OWC is provided in parallel with the reverse brake L & R / B. First ring gear R1 and second ring gear R1
The transmission output shaft O is connected to the carrier C2, and the transmission output shaft O is connected to the second carrier C2.

FIG. 3 is a diagram showing an engagement logic table at each gear position in the R range and the D range (the engagement is indicated by a triangle).
At the time of the range, the reverse clutch R / C and the low & reverse brake L & R / B are engaged. At the 1st speed of the D range, the low clutch L / C and the low & reverse brake L & R / B are engaged.
Is engaged, the low clutch L / C and the 2-4 brake 2-4B are engaged at the 2nd speed of the D range, and the low clutch L / C and the high clutch H / C are engaged at the 3rd speed of the D range.
At the 4th speed in the D range, the high clutch H / C and the 2-4 brake 2-4B are engaged.

FIG. 4 is a diagram showing a shift control system of an automatic transmission to which the shift control device of the first embodiment is applied, wherein 1 is a line pressure oil passage, 2 is a manual valve, 3 is a D range pressure oil passage,
Reference numeral 4 denotes an R-range pressure oil passage, and a manual valve 2 is a valve that can be switched by a select operation. The D-range is connected to the line pressure oil passage 1 and the D-range pressure oil passage 3, and the R range is a line pressure oil passage 1. And the R range pressure oil passage 4 are connected.

Reference numeral 5 denotes a pilot valve, and reference numeral 6 denotes a solenoid valve supply pressure oil passage. The pilot valve 5 controls the pressure of the line from the line pressure oil passage 1 to a constant supply pressure to the solenoid valve.

Reference numeral 7 denotes a first pressure control valve, which is a D range pressure oil passage 3
The low clutch pressure is generated by controlling the D range pressure from the motor through duty control, and is guided to the low clutch L / C via the low clutch pressure oil passage 8.

Reference numeral 9 denotes a second pressure control valve, which is a D range pressure oil passage 3
The high clutch pressure is generated by controlling the D range pressure from the motor through duty control, and is guided to the high clutch H / C via the high clutch pressure oil passage 10.

Reference numeral 11 denotes a third pressure control valve, which is a line pressure oil passage 1
2-4 by controlling the line pressure from
A brake pressure is generated and guided to a 2-4 brake 2-4B via a 2-4 brake pressure oil passage 12.

Reference numeral 13 denotes a fourth pressure control valve, which controls the D range pressure from the D range pressure oil passage 3 by duty control to produce a low & reverse brake pressure, and outputs a low & reverse brake pressure oil through a low & reverse brake pressure oil passage 14. & Reverse brake L &
Lead to R / B.

A fifth pressure control valve 15 controls the R range pressure from the R range pressure oil passage 4 by duty control to generate a reverse clutch pressure, and a reverse clutch R / C through a reverse clutch pressure oil passage 16. Lead to.

Reference numeral 17 denotes an AT control unit, which is a select position switch 18, an idle switch 19, a brake switch 20, an oil temperature sensor 21, an engine rotation sensor 22, a turbine rotation sensor 23 (turbine rotation speed detecting means), and an output shaft rotation (vehicle speed). ) A switch signal or a sensor signal from the sensor 24 (output shaft rotation number detecting means) or the like is input,
Various control arithmetic processes including shift control are performed based on these input information, and the solenoid valve driving current is output to each of the pressure control valves 7, 9, 11, 13, and 15 based on the processing results.

FIG. 5 is a diagram showing a first pressure control valve (a typical example of a pressure control valve) of an automatic transmission to which the transmission control device of the first embodiment is applied, and 7 is a first pressure control valve. High-speed ON / OFF solenoid valve 7 for controlling the solenoid valve supply pressure to the spool signal pressure by duty control (control by a pulse width modulation method) for applying a duty drive current to the solenoid coil
1, a spool signal pressure oil passage 72, and a spool valve 73 that operates using the oil pressure from the spool signal pressure oil passage 72 as a signal pressure and controls the D range pressure to a low clutch pressure.

Here, the low clutch pressure is set to _PCL , the pressure receiving areas of the spool valve 73 are set to S _A and S _B , and the high speed ON / O
The solenoid pressure from the FF solenoid valve 71 and P _SOL, the spring force of the spool valve 73 and F _SP, expression holds that _{P SOL × S A = P CL} (S A -S B) + F SP. Accordingly, the low clutch pressure P _{CL is, P CL = {S A /} (S A -S B)} P SOL over {F _SP / (S
_A− S _B )｝. That is, the low clutch pressure _PCL is controlled by controlling the energizing time (duty ratio) of the high-speed ON / OFF solenoid valve 71 to 0 to 100% (controlling the solenoid pressure _PSOL ).

The other pressure control valves 9, 11, 13, 15
Also has a configuration similar to that of the first pressure control valve 7, and can similarly independently control the hydraulic pressure.

Next, the operation will be described.

[2-3 Upshift Control Operation] FIGS. 6, 7 and 8 show the operation performed by the AT control unit 17.
Each step will be described below with a flowchart showing the flow of the -3 upshift control operation. In the 2-3 upshift, when a shift start command is output, the 2-4 brake 2-4B (first engagement element) that has been engaged in the second gear is released without the intervention of a one-way clutch. Then, the third gear is achieved by changing over by disengaging the released high clutch H / C (second engagement element).

In step 30, the shift FLG is set to FLG = 1 based on a shift start command issued when the operating point determined by the detected vehicle speed and throttle opening crosses the 2 → 3 upshift line on the shift schedule. Is done.

In step 31, a shift control timer t is started.

[0033] At step 32, the sensor signals such as the engine rotational speed N _E and the turbine speed Nt and the output shaft speed No and the throttle opening TH is read.

In step 33, the shelf pressure A of the release hydraulic pressure
Is set by A = engagement holding pressure + α. Here, fastening the holding pressure in the hydraulic pressure determined by the table data by the throttle opening TH and the engine speed N _E, alpha is a constant pressure. Note that the shelf pressure A is A = fastening holding pressure × 1.2.
The hydraulic pressure may be set to be higher than the engagement holding pressure according to the formula (safety factor).

In step 34, the fastening-side upper shelf pressure B is set. The engagement-side upper shelf pressure B is determined by the throttle opening TH.
Determined by the table data by the engine rotational speed N _E and (upper shelf pressure setting means).

In step 35, the turbine speed Nt at the time of the shift start command is set as the turbine speed initial value Nt1.

In step 36, the turbine rotational acceleration dNt at the time of the shift start command is obtained by a differential operation, and the operation value dNt is set as the turbine rotational acceleration initial value dNt1.

In step 40, when it is determined in step 45 that the filling is not completed, the turbine speed Nt at that time is read.

In step 41, the hydraulic pressure of the released 2-4 brake 2-4B is reduced to the shelf pressure A set in step 33, and the shelf pressure A is kept on standby (release pressure control section).

In step 42, an in-fill control is performed to gradually increase the engagement pressure of the high clutch H / C to be engaged from the return equivalent pressure at a predetermined gradient b (an engagement pressure control unit).

In step 43, an estimated turbine speed Ntx that follows the progress of the shift is calculated based on the turbine speed initial value Nt1, the turbine speed acceleration initial value dNt1, and the elapsed time t after the start of the shift (estimated turbine speed). Calculation means).

In step 44, a turbine speed deviation ΔNt between the detected turbine speed Nt and the estimated turbine speed Ntx is calculated by the equation ΔNt = Ntx−Nt (turbine speed difference calculating means).

In step 45, it is determined whether or not the turbine rotational speed deviation ΔNt calculated in step 44 exceeds a deviation target value ΔNta which is a threshold value for judging completion of the filling. When the determination is NO, the process proceeds to step 40. Return, YE
When the determination is S, the process proceeds to step S50. Steps 40 to 45 correspond to a gear stage control unit before gear shifting.

In step 50, the elapsed time t up to this point is set as the in-fill completion time t1.

In step 51, the release hydraulic pressure of the released 2-4 brake 2-4B is set to the release hydraulic pressure = Ac (t-
t1). In addition, A is a shelf pressure, c is a predetermined gradient, t is an elapsed time, and t1 is an infill completion time.

In step 52, the engagement side hydraulic pressure of the high clutch H / C to be engaged is increased by the engagement side oil pressure = return equivalent pressure + b × t1 + a × (t−t1). Note that a (> b) is a predetermined gradient.

At step 53, it is determined whether or not the elapsed time t by the timer exceeds the time obtained by adding the in-fill completion time t1 and the replacement time t2. Here, the changeover time t2 is set to a short time by confirming the completion of the filling in the fastening side by the processing of Steps 40 to 45, and making the release side stand by with the minimum hydraulic pressure for maintaining the fastening capacity. Steps 50 to 53 correspond to first torque phase control means.

In step 54, the release hydraulic pressure of the released 2-4 brake 2-4B is set to zero by drain to complete release.

In step 55, the engagement side hydraulic pressure of the high clutch H / C to be engaged is increased as it is by the same hydraulic system as in step 52.

In step 56, it is determined whether the engagement side hydraulic pressure of the high clutch H / C is equal to or higher than the upper limit shelf pressure B set in step 34, and the high clutch pressure is increased until the condition of step 56 is satisfied. Steps 54-
Step 56 corresponds to inertia phase control means.

In step 60, the turbine speed Nt and the output shaft speed No are read while the high clutch H / C is maintained at the upper limit shelf pressure B.

In step 61, the gear ratio i is calculated from the turbine speed Nt and the output shaft speed No by the equation i = Nt / No (corresponding to a gear ratio calculating means).

At step 62, the gear ratio i calculated at step 61 is the gear ratio ia (the ia =
1.0) or higher, and the high clutch H / C is set to the upper limit shelf pressure B until a shift end determination of YES is made.
Is maintained. Steps 60 to 62 correspond to second torque phase control means.

In step 63, the engagement hydraulic pressure of the high clutch H / C to be engaged is set to the line pressure P _L.

In step 64, the shift FLG is rewritten from 1 to FLG = 0 when the shift is completed.
Steps 63 and 64 correspond to post-shift gear stage phase control means.

At step 65, the timer is reset.

[2-3 Upshift Function] The time chart of FIG. 9 shows the 2-3 upshift action.

Looking at the shift command characteristics, the engagement side hydraulic pressure and the release side hydraulic characteristics, the turbine speed and the output shaft speed characteristics,
It can be seen that the shift control for each phase is performed according to the above flowchart. In FIG. 9, phase I corresponds to a gear stage before shifting, phase II corresponds to a first torque phase, phase III corresponds to an inertia phase, phase IV corresponds to a second torque phase, and phase V corresponds to a gear stage after shifting. .

As is apparent from the torque characteristics of the output shaft, by employing the shift control of the present invention, the torque pulling depth is suppressed to a small value, and the thrust torque is suppressed. , The first torque phase time is short, and a smooth gear shifting performance is realized by combining them.

[Detection of Inset Completeness] In the present invention, since the turbine speed deviation ΔNt exceeds the deviation target value ΔNta, it is detected that the inset (clutch piston stroke) on the engagement side is completed. It is characterized by

The reason why the completion of the filling can be detected based on the turbine speed deviation ΔNt will be described.

First, when the filling is completed and the fastening side has a torque capacity, this becomes the restraining torque of the drive system, and the turbine speed Nt decreases.

That is, if the decrease in the turbine speed Nt due to the fact that the fastening side has the torque capacity can be detected, the completion of the filling can be detected. However, the turbine speed Nt is simply monitored to determine the decrease in the speed. When you do
For example, in the case of an upshift, the turbine speed tends to increase before the shift, and if the turbine speed is reduced by a predetermined amount before the shift, the in-fill is already completed and the shift is further progressing. Will be detected. That is, it is necessary to provide a criterion for decreasing the rotation speed. For this reason, the turbine rotation speed initial value Nt1 and turbine rotation acceleration initial value dN
A turbine rotational speed estimation value Ntx that follows the progress of the shift is calculated from t1 and the elapsed time t after the start of the shift, and the difference between the turbine rotational speed estimated value Ntx and the detected turbine rotational speed Nt is used to calculate a turbine rotational speed deviation ΔNt. And

Therefore, when it is determined that the turbine rotational speed deviation ΔNt exceeds the deviation target value ΔNta which is a threshold value for judging the completion of the filling, the filling on the fastening side is completed, and the fastening side starts to have the torque capacity. Can be accurately detected.

[Driving Prevention of Idling] (1) In the pre-shift gear stage, the disengagement side is held at the engagement holding capacity until the inset is completed on the engagement side and the engagement capacity starts to be maintained.

(2) In the first torque phase, the shifting pressure is set by setting the sharing pressure so that the value obtained by adding the engagement side torque sharing ratio and the release side torque sharing ratio becomes 1.0 or more.

A) By the control of the above (1), at the initial stage of the shift, it is possible to surely prevent the idling due to the incomplete filling in the fastening side.

B) By the control of the above (2), at the time of changeover, it is possible to prevent an idle blow due to an insufficient transmission torque capacity on both the engagement side and the release side.

That is, the above-mentioned operations a) and b) reliably prevent the engine from blowing, so that the driver does not feel uncomfortable due to the engine blowing, and the pulling depth in the first torque phase is reduced. Shortening of the pulling time and prevention of thrust-up by feedback correction of air blowing, which is a problem of conventional control, can be achieved.

Here, if the insufficiency occurs on the fastening side, as shown in FIG. 10, a large response delay occurs in the increase in hydraulic pressure, and surge and vibration also occur.

Insufficient capacity on the fastening side due to the delay in hydraulic response causes air blowing and torque reduction, and surge and vibration cause a thrust-up shock, which extremely deteriorates the shifting performance.

On the other hand, if the filling is completed at the time when the full-scale shift change is performed on the engagement side, no flow rate is generated thereafter, so that the hydraulic response is extremely improved.

(Other Embodiments) In the first embodiment, an example of application to an upshift has been described. However, the control method of the present invention may be applied to a downshift.

[0074]

According to the first aspect of the present invention, at the time of shifting, the occurrence of engine idling is reliably prevented, so that the torque pulling depth in the torque phase is reduced and the thrust torque is suppressed. Shorten the torque phase time,
The effect of being able to provide a shift control device for an automatic transmission that achieves smooth shift performance is obtained.

According to the second aspect of the present invention, there is provided the first aspect.
In addition to the effects of the invention described above, it is possible to prevent a blow due to an insufficient transmission torque capacity on both the fastening side and the release side at the time of switching.

In the invention according to claim 3, claim 1
Alternatively, in addition to the effect of the invention described in claim 2, the inertia phase can be performed in a short time only by raising the upper shelf pressure only on the fastening side until the upper limit shelf pressure is attained. The second torque phase in which the change is suppressed can be set.

According to the fourth aspect of the present invention, a first aspect is provided.
In addition to the effects of the third aspect of the present invention, the degree of freedom of control is higher than that of a conventional control valve unit having a device for controlling shelf pressure, timing, and the like and a shift valve, and the valve unit is simplified and lightweight. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a diagram corresponding to claims showing a shift control device for an automatic transmission according to the present invention.

FIG. 2 is a diagram illustrating a gear train of an automatic transmission to which the shift control device according to the first embodiment is applied.

FIG. 3 is a diagram showing a logic table for engaging each gear in an R range and a D range in the automatic transmission to which the shift control device of the first embodiment is applied.

FIG. 4 is a diagram showing a hydraulic control system of the automatic transmission to which the transmission control device of the first embodiment is applied.

FIG. 5 shows a first example of the hydraulic control system according to the first embodiment.
It is a figure which shows a pressure control valve concretely.

FIG. 6 is a diagram illustrating a shift control device A of the automatic transmission according to the first embodiment;
4 is a flowchart 1 showing a flow of a 2-3 upshift control operation performed by a T control unit.

FIG. 7 shows a shift control device A of the automatic transmission according to the first embodiment.
6 is a flowchart 2 showing a flow of a 2-3 upshift control operation performed by the T control unit.

FIG. 8 shows A of the shift control device for the automatic transmission according to the first embodiment.
4 is a flowchart 3 showing a flow of a 2-3 upshift control operation performed by the T control unit.

FIG. 9 is a time chart showing characteristics of the shift control device for the automatic transmission according to the first embodiment at the time of 2-3 upshift.

FIG. 10 is a time chart showing engagement hydraulic pressure characteristics at the time of an upshift in the shift control device for the automatic transmission according to the first embodiment.

FIG. 11 is a time chart showing various characteristics at the time of an upshift in a shift control device for a conventional automatic transmission.

[Explanation of symbols]

 a first fastening element b second fastening element c turbine speed detecting means d estimated turbine speed calculating means e turbine speed deviation calculating means f gear shift phase control means before shifting f1 release pressure control section f2 fastening pressure control section g 1 torque phase control means h upper limit shelf pressure setting means i output shaft rotation speed detection means j gear ratio calculation means k inertia phase control means m second torque phase control means n gear stage phase control means after shifting

Claims (4)

[Claims] When a shift start command is output, a first engagement element that has been engaged in a gear before shifting is released without intervening a one-way clutch, and a released second engagement element is released. In a shift control device for an automatic transmission that achieves a gear after a shift by changing over, a turbine speed detecting unit that detects a turbine speed, a turbine speed and a turbine at a time when a shift start command is output. Estimated turbine speed calculating means for calculating the estimated turbine speed following the shift based on the rotational acceleration and the elapsed time after the start of the shift, and calculating the turbine speed deviation between the detected turbine speed and the estimated turbine speed. Means for calculating a turbine rotation speed deviation, and when a shift start command is output, the release pressure of the first fastening element is reduced until the turbine rotation speed deviation reaches a set value. A release pressure control unit that lowers the pressure to a fixed pressure obtained by adding a margin pressure to the binding holding pressure and waits at the constant pressure, and a second engagement until the shift start command is output and the turbine rotational speed deviation reaches a set value. A gear stage phase control means before shifting by a fastening pressure control unit for performing an indentation control for gradually increasing the fastening pressure of the element from a return equivalent pressure at a predetermined gradient;
First torque phase control means for performing a shift change by lowering the release side oil pressure of the fastening element at a predetermined gradient and increasing the engagement side oil pressure of the second engagement element at a predetermined gradient. Transmission control device for automatic transmission. 2. The shift control device for an automatic transmission according to claim 1, wherein the hydraulic pressure contributing to the generation of the transmission torque of the fastening element is set to “effective hydraulic pressure”, and is released from the engaged fastening element during gear shifting. When the transmission torque of any one of the fastening elements to be fastened to the fastening element is set to zero, the rotation ratio of each rotating member can be kept from just changing due to the transmission torque of one of the remaining fastening elements. At this time, the transmission torque of this one fastening element is referred to as “sharing torque” with respect to the transmission input torque, and the hydraulic pressure effective to generate the “sharing torque” is referred to as “sharing pressure”. When the ratio with respect to the sharing pressure is defined as “sharing ratio”, the first torque phase control means sets the value obtained by adding the engagement side torque sharing ratio and the release side torque sharing ratio to 1.0 or more. Shift control device for an automatic transmission, characterized in that the means for performing changeover shift by setting a frequency 担圧 to so that. 3. The shift control device for an automatic transmission according to claim 1, wherein an upper limit shelf pressure setting unit that sets an upper limit shelf pressure exceeding an engagement holding capacity as an engagement side hydraulic pressure of the second engagement element. An output shaft rotation number detecting means for detecting an output shaft rotation number of the automatic transmission; a gear ratio calculating means for calculating a gear ratio which is a ratio of the turbine rotation number detection value to the output shaft rotation number detection value; An inertia phase control means for setting the release hydraulic pressure of the first engagement element as a drain and increasing the engagement hydraulic pressure of the second engagement element as it is until the set upper shelf pressure is reached when the shift speed change time by the torque phase control means is completed; Second torque phase control means for maintaining the upper limit shelf pressure as it is until the calculated gear ratio becomes the shift completion gear ratio when the engagement side hydraulic pressure of the second engagement element reaches the upper limit shelf pressure; And a post-shift gear stage phase control means for increasing the engagement side oil pressure of the second engagement element from the upper limit shelf pressure to the line pressure when the calculated gear ratio becomes the shift completion gear ratio. Transmission control device. 4. The shift control device for an automatic transmission according to claim 1, wherein the hydraulic control means of the first engagement element and the hydraulic control means of the second engagement element are controlled based on a drive range pressure. A shift control device for an automatic transmission, wherein each of the shift control devices independently electronically controls a hydraulic pressure.