JP2013083312A - Shift control device of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately and instantly release meshing without generating a neutral state in fastening progress of a frictional element and a shift releasing meshing of engagement elements.SOLUTION: In a period of gradually increasing transmission torque (Tf) to the maximum value by fastening a direct clutch from the time when a shift is commanded, the torque is increased at a normal rate α in a first period TM1 and is increased at a gentle rate β in a second period TM2. Accordingly, transmission torque (Tc) of a reduction brake (R/B) is decreased rapidly in the first period and decreased gently in the second period. By imparting a pulling force (Fr) to the R/B at a suitable timing in the second period, the transmission torque Tc is decreased to a value corresponding to the pulling force Fr. The R/B is switched from a meshing state to a non-meshing state by the pulling force Fr and the shift is completed to perform the shift without generating a neutral state. By imparting Fr in the second period TM2 when the Tc of the R/B is gently decreased, a timing t3 to impart Fr can be controlled to be a timing generated at an instant t4 when releasing meshing of the R/B is suitable.

Description

  The present invention relates to a shift control device for an automatic transmission, and in particular, an operation for switching a frictional transmission element such as a friction clutch or a friction brake from a released state to an engaged state, and an engagement type transmission element such as a dog clutch. The present invention relates to a technique for improving the quality of a shift performed by changing so-called shift elements by an operation of switching from a meshing state to a non-meshing state by applying.

  Conventionally, for example, Patent Document 1 discloses an automatic transmission having a shift that switches a frictional transmission element from a disengaged state to an engaged state and switches an engaging transmission element from a meshing state to a non-meshing state by applying a pulling force. Something like the description has been proposed.

This automatic transmission is used in the motor transmission system of a hybrid vehicle. Which of the high-speed transmission system that transmits the rotation of the electric motor at a high speed and the low-speed transmission system that transmits the rotation of the electric motor at a low speed is selected? It is for determining.
Briefly, a low-speed transmission system can be selected according to the engagement state of the dog clutch and the release state of the friction clutch, and a high-speed transmission system is selected according to the non-engagement state of the dog clutch and the engagement state of the friction clutch. Can do.

  In the case of such an automatic transmission, when switching (shifting) the state using the low-speed transmission system to the state using the high-speed transmission system, the dog clutch is switched from the meshing state to the non-meshing state, and the friction clutch is released from the released state. The gear shift (upshift) performed by switching to the engaged state is performed.

  In the invention described in Patent Document 1, at the time of this speed change, the dog clutch is first switched from the meshing state to the non-meshing state, and then the friction clutch is switched from the disengaged state to the engaged state to perform the shift (upshift). .

JP 2010-188895 A

  However, when the dog clutch is first switched to the non-engaged state and then the friction clutch is switched to the engaged state, a time during which both the dog clutch and the friction clutch cannot transmit power temporarily occurs. The aircraft enters a neutral state (neutral state).

  In such a temporary neutral state (neutral state) of the automatic transmission, the driving torque of the vehicle is reduced to 0 to give a sense of deceleration, and the input side rotation speed (rotation speed of the electric motor) of the automatic transmission is temporarily set. When the input rotational speed is lowered to the gear ratio equivalent value after the shift, a shift shock occurs, and in any case, the shift quality is deteriorated.

  In order to solve this problem, before switching the dog clutch to the non-engagement state, the state switching from the disengaged state to the engaged state is first advanced in order to prevent the time for the neutral state from occurring. It is conceivable to switch the dog clutch from the meshing state to the non-meshing state by applying a pulling force when the predetermined degree of progress is reached.

In this case, the timing of applying the pulling force for bringing the dog clutch into the non-engagement state is when the torque sharing ratio of the dog clutch is increased by the progress of the engagement of the friction clutch, and the torque sharing of the dog clutch is decreased accordingly. good.
The reason is that if the torque sharing (transmission torque) of the dog clutch is small, the pulling force for disengaging the dog clutch may be small, and the energy consumption when disengaging the dog clutch is reduced, which is advantageous. Because there is.

However, in order to reduce the shift time to a short time within the target time so as to achieve a predetermined shift quality, the engagement speed of the friction clutch needs to be a speed corresponding to this.
Therefore, it is necessary to advance the engagement of the friction clutch at a certain high speed. When the engagement advance speed of the friction clutch is determined in consideration of the shift quality (shift time) as described above, the following problems occur.

In other words, when the engagement speed of the friction clutch is as high as possible, the reduction in the torque sharing (transmission torque) of the dog clutch that occurs in response to this is a high speed corresponding to the engagement speed of the friction clutch. Will be done.
However, when the torque sharing (transmission torque) decreasing speed of the dog clutch is so high, the dog clutch is brought into a non-engagement state at the timing when the torque sharing (transmission torque) of the dog clutch is decreased to a good value. For this reason, it is difficult to control the removal force.

  For this reason, the timing for switching the dog clutch to the non-engagement state is often inappropriate, and this timing is delayed, and the automatic transmission tends to interlock, causing a torque pulling shock or the above timing being too early. The temporary increase in the transmission input rotational speed causes a problem related to the deterioration of the shift quality that a large shift shock occurs at the end of the shift.

  If the engagement speed of the friction clutch is reduced, a decrease in the dog clutch torque sharing (transmission torque) that occurs in response to this will occur at a corresponding low speed, and the dog clutch torque sharing (transmission torque) will occur. ) At the timing when it has just decreased to a good value, it becomes possible to control to apply a pulling force for bringing the dog clutch into the non-engagement state, and the above problem can be avoided.

  However, in this case, the low engagement speed of the friction clutch extends the shift time of the automatic transmission beyond the allowable time for the shift quality, resulting in deterioration of the shift quality and the time during which the friction clutch is in the slip state. This causes a problem that the durability is remarkably reduced due to the length of the steel.

In the present invention, as is apparent from the above description, the engagement-type transmission element should be switched from the meshing state to the non-meshing state by applying a pulling force. It is in the latter period after the transmission torque of the engagement type transmission element decreases to a small value, and if the state switching speed from the release state of the friction type transmission element to the engagement state is moderated in this latter period,
It is possible to apply the extraction force to the engagement type transmission element at just the right timing without causing an extension that causes a problem of the shift time, and to solve all the above problems. From the viewpoint, an object is to provide a shift control device for an automatic transmission that embodies this idea.

For this purpose, the shift control device for an automatic transmission according to the present invention is constituted as follows.
First, an automatic transmission that is a premise of the present invention will be described.
Shifting is possible by the operation of switching the frictional transmission element from the released state to the engaged state and the operation of switching the engagement type transmission element from the meshing state to the non-meshing state by applying a pulling force.

The speed change control device of the present invention is characterized by a configuration in which the following friction type speed change element switching speed control means and engagement type speed change element switching means are provided for the above automatic transmission.
The former frictional transmission element switching speed control means switches the frictional transmission element from the released state to the engaged state more slowly in the latter period than in the previous period, and
The latter engagement type transmission element switching means is configured to switch to the engagement type transmission element from a predetermined timing at a later stage when the friction type transmission element is slowly switched from the released state to the engaged state by the former friction type transmission element switching speed control unit. By applying a pulling force, the engagement type transmission element is switched from the meshing state to the non-meshing state.

In the shift control device for an automatic transmission according to the present invention,
The switching of the frictional transmission element from the released state to the engaged state proceeds more slowly in the latter period than in the previous period, and the engagement type transmission element is engaged at a predetermined timing in the latter period to apply the extraction force to the engagement type transmission element. Therefore, the following effects can be obtained.

  In other words, prior to switching from the meshing state of the engagement type transmission element to the non-meshing state, the switching of the friction type transmission element from the release state to the fastening state proceeds, and accordingly, the transmission torque of the engagement type transmission element decreases. When this occurs, the engagement type speed change element is switched from the meshing state to the non-meshing state by the pulling force, and the corresponding speed change is performed.

Accordingly, there is no time for both the engagement type transmission element and the friction type transmission element to be unable to transmit power, so that the automatic transmission does not enter a neutral state (neutral state) in which power transmission cannot be performed during shifting, It is possible to prevent a feeling of deceleration due to the drive torque becoming zero during the shift.
For the same reason, the input side rotation speed of the automatic transmission is not temporarily increased, and a shift shock accompanying this input rotation change can be avoided.
Therefore, according to the present invention, in any case, it is possible to solve the problem relating to the deterioration of the shift quality that the conventional shift control device described in Patent Document 1 has.

Further, according to the present invention, since the state switching of the friction transmission element from the released state to the engagement state is gradually advanced in the latter period when the pulling force is applied to the engagement transmission element, the engagement corresponding to the state switching of the friction transmission element is performed. The reduction in the transmission torque of the combined transmission element can also be made gradual.
For this reason, it is easy to control to apply a pulling force for bringing the engagement type transmission element into the non-engagement state at the timing when the transmission torque of the engagement type transmission element has just decreased to a good value.

  Therefore, the switching timing of the engagement type transmission element to the non-engagement state does not become inappropriate, and this timing is delayed, the automatic transmission tends to be interlocked, a torque pulling shock occurs, or the above timing is accelerated. Therefore, it is possible to avoid the problem relating to the deterioration of the shift quality, in which a large shift shock occurs due to the temporary increase in the transmission input rotational speed.

Moreover, in solving the above problems, the state change of the friction transmission element is gradually advanced only in the latter period when the pulling force is applied to the engagement transmission element. To keep the speed normal and fast,
The speed at which the engagement speed of the frictional transmission element reduced as described above does not increase the shift time of the automatic transmission beyond the allowable time in terms of shift quality, and the slipping time of the frictional transmission element during shift Is not so long as to affect the durability of the friction transmission element.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram illustrating a drive device for a hybrid vehicle including an automatic transmission including a shift control device according to an embodiment of the present invention, together with a shift control system for the automatic transmission. 2 is a flowchart showing a shift control program for upshifting executed by a transmission controller in FIG. 3 is an operation time chart at the time of upshift control by the shift control program of FIG.

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
<Configuration of Example>
FIG. 1 shows a drive device for a vehicle including an automatic transmission having a shift control device according to an embodiment of the present invention, which is configured as described below.

The drive device includes a prime mover 1 that enables an electric motor, an automatic transmission 2, a final reduction gear set 3, a differential gear device 4, and left and right wheel drive shafts 5L and 5R.
The automatic transmission 2 is configured such that the input shaft 11 and the output shaft 12 are coaxially butted so as to be rotatable relative to each other, and a planetary gear type speed change mechanism 13 is interposed between the input / output shafts 11 and 12.

  The planetary gear type speed change mechanism 13 includes a sun gear 14 coupled to the input shaft 11, a ring gear 15 concentrically surrounding the sun gear 14, a set of planetary pinions 16 meshing with the sun gear 14 and the ring gear 14, and the planetary pinions It comprises a simple planetary gear set comprising a carrier 17 that rotatably supports 16.

The carrier 17 is drivingly coupled to the output shaft 12 so that the direct coupling D / C can be appropriately coupled between the coaxial butted ends of the input shaft 11 and the output shaft 12.
Further, the ring gear 15 can be appropriately fixed to the transmission case 18 by the reduction brake R / B.

The direct clutch D / C corresponds to the friction type speed change element in the present invention, and is constituted by a friction clutch or the like whose state is switched between a released state and an engaged state hydraulically or electrically.
The reduction brake R / B corresponds to the engagement type transmission element in the present invention, and is constituted by a dog clutch type meshing brake and functions as follows.

  That is, the reduction brake R / B is engaged or disengaged by applying a hydraulically actuated or electric meshing force or a pulling force. Is in a non-fixed state.

  By the way, the switching from the meshing state to the non-meshing state by the application of the above-mentioned extraction force is performed while the transmission torque of the reduction brake R / B (engaging transmission element) is larger than a predetermined value corresponding to the above-mentioned extraction force. When the transmission torque of the reduction brake R / B (engagement speed change element) drops below the specified value, the reduction brake R / B (engagement speed change element) is engaged by the pulling force. The state is switched to the non-engagement state.

The automatic transmission 2 described above is practically used by connecting the output shaft (motor shaft) of the speed reducer 1 to the input shaft 11 and connecting the drive gear 3a of the final reduction gear set 3 to the output shaft 12.
The driven gear 3b of the final reduction gear set 3 is coupled to the left and right wheel drive shafts 5L and 5R via the differential gear device 4.

<Operation of Example>
The rotation of the prime mover 1 is transmitted to the input shaft 11 of the automatic transmission 2, and the automatic transmission 2 can transmit this input rotation to the left and right wheel drive shafts 5L and 5R as follows.
The automatic transmission 2 disengages the input shaft 11 and the output shaft 12 by releasing the direct clutch D / C (friction type transmission element), and sets the reduction brake R / B (engagement type transmission element) to the non-engagement state. If the ring gear 15 is rotatable,
In the neutral state in which the rotation to the input shaft 11 cannot be directed to the output shaft 12, the left and right wheel drive shafts 5L and 5R cannot be driven, and the vehicle can be stopped.

  From this neutral state, when the direct clutch D / C (friction type transmission element) is engaged and the input shaft 11 and the output shaft 12 are coupled, the automatic transmission 2 directs the rotation to the input shaft 11 to the output shaft 12 as it is. In this state, the left and right wheel drive shafts 5L and 5R can be driven at a high speed to drive the vehicle.

  When the reduction gear R / B (engagement speed change element) is engaged from the neutral state and the ring gear 15 is fixed, the automatic transmission 2 decelerates the rotation to the input shaft 11 and directs it from the carrier 17 to the output shaft 12. The low speed stage is selected, and the left and right wheel drive shafts 5L and 5R can be driven at a low speed to drive the vehicle.

<Shift control of automatic transmission>
The release state of the direct clutch D / C (friction type transmission element), the engagement state, and the meshing state and non-meshing state of the reduction brake R / B (engagement type transmission element) are controlled by the transmission controller 21,
The transmission controller 21 controls the shift of the automatic transmission 2 by switching the states of the direct clutch D / C (friction type transmission element) and the reduction brake R / B (engagement type transmission element).

For this reason, the transmission controller 21 receives a signal from the sensor group 22 that detects shift control information such as the vehicle speed VSP and the accelerator opening APO required for the shift control.
The transmission controller 21 determines whether the automatic transmission 2 should be in the low speed stage selection state or the high speed stage selection state based on these input information, and the comparison result between this determination result and the currently selected gear stage As appropriate, a shift (downshift) from the high speed stage selection state to the low speed stage selection state is commanded, or a shift (upshift) is commanded from the low speed stage selection state to the high speed stage selection state.

When a downshift command is issued, the transmission controller 21 switches the direct clutch D / C (friction type transmission element) from the engaged state to the released state, and the reduction brake R / B (engagement type transmission element) is engaged from the non-engaged state. By switching to, the automatic transmission 2 is downshifted.
At the time of upshift command, the transmission controller 21 switches the direct clutch D / C (friction type transmission element) from the released state to the engaged state, and the reduction brake R / B (engagement type transmission element) from the meshing state to the non-meshing state. By switching to, the automatic transmission 2 is upshifted.

In this embodiment, in particular, among these shifts, the direct clutch D / C (friction type transmission element) is switched from the disengaged state to the engaged state, and the reduction brake R / B (engagement type transmission element) is engaged. In connection with the technology that suitably performs the shift (upshift) of the automatic transmission 2 by switching to
Therefore, in this embodiment, the transmission controller 21 executes the control program of FIG. 2 and performs the upshift of the automatic transmission 2 as shown in the time chart of FIG.

In step S11 in FIG. 2, it is checked whether or not an upshift command to a high speed is generated in the low speed stage selected state of the automatic transmission 2, that is, whether or not the instant t1 in FIG. 3 has been reached.
While the upshift command is not generated, the control of FIG. 2 is unnecessary, and thus the control is terminated as it is in FIG.

  When it is determined in step S11 in FIG. 2 that an upshift command has been generated, control proceeds to step S12 and thereafter, and the transmission torque Tf of the direct clutch D / C (friction type transmission element) is between the instants t1 and t4 in FIG. The direct clutch D / C (friction type transmission element) in the disengaged state is engaged so as to increase in the manner seen in FIG.

  The increase in the direct clutch transmission torque Tf between instants t1 and t4 in FIG. 3 is that the direct clutch transmission torque Tf increases from 0 at a relatively rapid time change gradient α in the first half of the predetermined time TM1 from the shift command time t1. In the latter half of the predetermined time TM2 (until the instant t4) from the instant t2 when the predetermined time TM1 has elapsed since the shift command time t1, the direct clutch transmission torque Tf increases from the increased value at the instant t2 with a relatively slow time change gradient β. Finally, the maximum value (Max) is assumed.

Here, the increase speed α of the direct clutch transmission torque Tf during the previous period TM1 between the instants t1 and t2 is based on a normal concept, so that the shift time can be a short time within the target time on the shift quality. Decide on speed.
However, the increasing speed β of the direct clutch transmission torque Tf during the latter period TM2 between the instants t2 and t4 is set to be slower than the above α, and is determined as follows.

If the increase speed of the direct clutch transmission torque Tf remains the same as α in the previous period even during the latter period TM2 between the instants t2 and t4, the reduction brake R / R generated in response to the increase in the direct clutch transmission torque Tf. The torque sharing (reduction brake transmission torque Tc) of B (engagement type transmission element) is also reduced at a high speed corresponding to the increasing speed of the direct clutch transmission torque Tf.
Thus, if the reduction speed of the reduction brake transmission torque Tc is high, the reduction brake R / B (engaging transmission element) is disengaged at the timing when the reduction brake transmission torque Tc has just decreased to a good value. Therefore, it is difficult to control the force Fr at the moment t3 in FIG.

In this case, the switching timing of the reduction brake R / B (engaging transmission element) to the non-engagement state is not appropriate as shown by t4 in FIG. .
When the switching timing of the reduction brake R / B (engagement speed change element) to the non-engagement state is delayed from the appropriate timing t4, the automatic transmission 2 tends to be interlocked, causing a torque pulling shock,
Conversely, if the switching timing of the reduction brake R / B (engagement-type shift element) to the non-engagement state is too early than the appropriate timing t4, a large shift shock occurs at the end of the shift due to a temporary increase in the input speed of the transmission. In any case, however, there arises a problem that the transmission quality deteriorates.

  In view of this problem, the gradual increase speed β of the direct clutch transmission torque Tf during the latter period TM2 between the instants t2 and t4 is timed at the timing t3 when the reduction brake transmission torque Tc has just decreased to a good value, and the reduction Reduction brake transmission so that the braking force Fr is applied to the brake R / B (engagement-type transmission element) (the reduction brake R / B is switched to the non-engagement state at an appropriate timing t4). The speed of decrease of the torque Tc is determined as an increase speed of the direct clutch transmission torque Tf that can make the speed lower.

  Of the first period TM1 between the instants t1 and t2 and the second period TM2 between the instants t2 and t4, the latter latter period TM2 is an appropriate timing t4 for switching the reduction brake R / B to the non-engagement state. The former time TM1 is the torque phase time (from the shift command time t1, the reduction brake R / B is not meshed). The time length obtained by subtracting the late time TM2 from the initial target value of the effective phase ratio, which is the input / output rotation ratio of the transmission, starts to change from the pre-shift value to the post-shift value when the switch is completed. And

In step S12 in FIG. 2, the above-described increasing speed (rapid increase speed α and slow increase speed β) of the direct clutch transmission torque Tf, the first period TM1 and the second period TM2 are read.
In the next step S13, the direct clutch D / C (friction type transmission element) is engaged and advanced so that the direct clutch transmission torque Tf increases at the rapid increase speed α.
In step S14, it is checked whether or not the instant t2 in FIG. 3 has been reached, depending on whether or not the previous period time TM1 has elapsed since the shift command time t1.

Prior to the instant t2 when the previous period TM1 elapses, the direct clutch D / C (friction type transmission element) continues to be engaged so that the direct clutch transmission torque Tf increases at the rapid increase speed α by repeatedly executing step S13. Let
As a result of this engagement, the direct clutch D / C (friction type transmission element) increases the torque sharing ratio (transmission torque Tf) at the speed α, and the transmission torque of the reduction brake R / B (engagement type transmission element) is increased by this increase. Tc is rapidly reduced at a corresponding speed as shown in FIG.

When it is determined in step S14 that the previous period TM1 has passed (has reached the instant t2 in FIG. 3), in step S15, the direct clutch D / C (friction-type shift) is set so that the direct clutch transmission torque Tf increases at the slowly increasing speed β. The element is advanced.
Therefore, step S15 corresponds to the frictional transmission element switching speed control means in the present invention.
In step S16, it is checked whether or not the instant t4 in FIG. 3 has been reached based on whether or not the late period TM2 has elapsed from the TM1 time elapsed instant t2.

Before the instant t4 when the late period TM2 elapses, it is checked in step S17 whether or not (TM2-TM3) time has elapsed from the instant t2 and the instant t3 in FIG. 3 has been reached, and (TM2-TM3) time has yet to elapse. While it is determined that it is not (before the instant t3 in FIG. 3), the direct clutch D / C (friction type) is performed so that the direct clutch transmission torque Tf increases at the slowly increasing speed β by repeatedly executing step S15. The engagement of the transmission element) is continued.
As a result of this engagement, the direct clutch D / C (friction type transmission element) increases the torque sharing ratio (transmission torque Tf) at the speed β, and the transmission torque of the reduction brake R / B (engagement type transmission element) is increased by this increase. Tc is gradually reduced at a corresponding speed as shown in FIG.

When it is determined in step S17 that (TM2-TM3) time has elapsed from the instant t2 (to reach the instant t3 in FIG. 3), step S15 is repeatedly executed after step S18 is executed.
In step S18, a pulling force Fr for switching the reduction brake R / B (engagement type transmission element) from the meshing state to the non-meshing state is applied as shown in FIG.
Therefore, step S18 corresponds to the engaging transmission element switching means in the present invention.
When the reduction brake transmission torque Tc drops to a small value at the instant t4, this pulling force Fr switches the reduction brake R / B (engagement speed change element) from the meshing state to the non-meshing state, and sets the transmission torque Tc to 0. Set to a small planned value.

  Even during the application of the pulling force Fr, step S15 is repeatedly executed to continue the engagement of the direct clutch D / C (friction type transmission element) so that the direct clutch transmission torque Tf increases at the slow increase speed β. .

  When it is determined in step S16 that the later time TM2 has elapsed from the TM1 time elapsed instant t2 (the moment t4 in FIG. 3 has been reached), the control proceeds to step S19, where the reduction brake R / B (engagement speed change element) The pulling force Fr to zero is set to 0 as shown in FIG. 3, and the direct clutch D / C (friction type transmission element) is completely engaged so that the direct clutch transmission torque Tf becomes the maximum value Max.

  Switching operation from the released state of the direct clutch D / C (friction type transmission element) to the engaged state and the switching operation from the meshing state of the reduction brake R / B (engagement type transmission element) to the non-engagement state as described above. Thus, the automatic transmission 2 is shifted (upshifted) from the low speed stage selection state to the high speed stage selection state.

After the completion of such a shift, in step S20 in FIG. 2, the direct clutch transmission torque Tf, which is the fastening speed α and the slow increase speed β, of the direct clutch D / C (friction type transmission element), and the direct clutch transmission torque. The first period TM1 and the second period TM2 in which Tf is rapidly increased at the speed α and slowly increased at the speed β are updated by the following learning (1) to (6) to contribute to the shift control after the next time.
Therefore, step S20 also corresponds to the frictional transmission element switching speed control means in the present invention.

<Learning (1)>
The slow increase speed β of the direct clutch transmission torque Tf, which specifies the gradual engagement progression speed of the direct clutch D / C (friction type transmission element) in the second half of the instant t2 to t4, is the direct clutch D / C (friction type transmission element). ) From the upshift command time t1 when the switching operation from the disengaged state to the engaged state is started, the reduction brake R / B (engagement type transmission element) is released by the increase of the direct clutch transmission torque Tf due to the progress of the operation. Learning control is performed as follows according to the actual torque phase times t1 to t4 until the instant t4 when the meshing state is switched from the meshing state to the non-meshing state by Fr.

  That is, when the actual torque phase time t1 to t4 is longer than the target torque phase time, the actual torque phase time t1 is increased by increasing (suddenly) increasing the speed β of the direct clutch transmission torque Tf and shortening the latter period time TM2. The slow increase speed β of the direct clutch transmission torque Tf is learned and controlled so that ˜t4 becomes the target torque phase time, and the slow increase speed β of the direct clutch transmission torque Tf is updated and changed to this learning value.

  Conversely, when the actual torque phase time t1 to t4 is shorter than the target torque phase time, the actual torque phase is increased by decreasing (gradually) the slow increase speed β of the direct clutch transmission torque Tf and extending the latter period time TM2. The slow increase speed β of the direct clutch transmission torque Tf is learned and controlled so that the time t1 to t4 becomes the target torque phase time, and the slow increase speed β of the direct clutch transmission torque Tf is updated and changed to this learning value.

<Learning (2)>
The direct clutch transmission torque Tf slow increase speed β further decreases the direct clutch transmission torque Tf change speed from the sudden increase speed α to the slow increase speed β, which reduces the direct clutch D / C (friction-type transmission element) state switching speed. Learning control is performed as follows according to the actual late time t2 to t4 from the start timing t2 to the instant t4 when the reduction brake R / B (engagement type shift element) is switched from the meshing state to the non-meshing state by the pulling force Fr. .

  That is, when the actual late period t2 to t4 is longer than the target late period, the actual late period t2 to t4 is reduced by increasing the sudden increase rate β of the direct clutch transmission torque Tf (suddenly) and reducing the late period TM2. The slow increase speed β of the direct clutch transmission torque Tf is learned and controlled so that the target late time is reached, and the slow increase speed β of the direct clutch transmission torque Tf is updated and changed to this learning value.

  Conversely, if the actual late time t2 to t4 is shorter than the target late time, the slow increase speed β of the direct clutch transmission torque Tf is decreased (slowly) and the late time TM2 is extended to increase the actual late time t2 to The slow increase speed β of the direct clutch transmission torque Tf is learned and controlled so that t4 becomes the target later time, and the slow increase speed β of the direct clutch transmission torque Tf is updated and changed to this learning value.

<Learning (3)>
The direct clutch transmission torque Tf sudden increase speed α, which specifies the sudden clutch advancement speed of the direct clutch D / C (friction type transmission element) in the first half of the instant t1 to t2, is the direct clutch D / C (friction type transmission element). From the upshift command time t1 when the switching operation from the released state to the engaged state is started, the reduction brake R / B (engagement-type transmission element) is released by the increase in the direct clutch transmission torque Tf due to the progress of the operation. Thus, learning control is performed as follows according to the actual torque phase times t1 to t4 until the instant t4 when the meshing state is switched to the non-meshing state.

  In other words, if the actual torque phase time t1 to t4 is longer than the target torque phase time, the actual torque phase time t1 to t1 is increased by increasing (rapidly) the rapid increase speed α of the direct clutch transmission torque Tf and shortening the late period TM2. The rapid increase speed α of the direct clutch transmission torque Tf is learned and controlled so that t4 becomes the target torque phase time, and the slow increase speed β of the direct clutch transmission torque Tf is updated and changed to this learning value.

  Conversely, if the actual torque phase time t1 to t4 is shorter than the target torque phase time, the rapid increase rate α of the direct clutch transmission torque Tf is reduced (slowly), and the late time TM2 is extended to increase the actual torque phase time. The rapid increase speed α of the direct clutch transmission torque Tf is learned and controlled so that the time t1 to t4 becomes the target torque phase time, and the rapid increase speed α of the direct clutch transmission torque Tf is updated and changed to this learning value.

<Learning (4)>
The direct clutch transmission torque Tf sudden increase speed α further decreases the direct clutch transmission torque Tf change speed from the sudden increase speed α to the slow increase speed β. Learning control is performed as follows according to the actual late period t2 to t4 from the timing t2 to the instant t4 when the reduction brake R / B (engaging transmission element) is switched from the meshing state to the non-meshing state by the extraction force Fr.

  In other words, when the actual late period t2 to t4 is longer than the target late period, the actual late period t2 to t4 is the target by increasing (rapidly) the rapid increase rate α of the direct clutch transmission torque Tf and shortening the previous period TM1. The rapid increase speed α of the direct clutch transmission torque Tf is learned and controlled so as to reach the latter period, and the rapid increase speed α of the direct clutch transmission torque Tf is updated and changed to this learned value.

  Conversely, if the actual late time t2 to t4 is shorter than the target late time, the rapid increase speed α of the direct clutch transmission torque Tf is reduced (slowly) and the previous time TM1 is extended, thereby causing the actual late time t2 to t4. Is subject to learning control of the direct clutch transmission torque Tf rapid increase rate α so that the target late time becomes the target later time, and the rapid increase rate α of the direct clutch transmission torque Tf is updated and changed to this learned value.

<Learning (5)>
Direct clutch (friction-type transmission element) engagement that switches the increase speed of direct clutch transmission torque Tf from sudden increase speed α to slow increase speed β in order to reduce the engagement speed of direct clutch D / C (friction-type transmission element) Progression speed decrease start timing t2 is the direct clutch transmission torque Tf due to the progress of the operation from the upshift command time t1 when the direct clutch D / C (friction type transmission element) is released from the disengaged state to the engaged state. The learning brake is controlled as follows according to the actual torque phase time t1 to t4 until the instant t4 when the reduction brake R / B (engagement type transmission element) is switched from the meshing state to the non-meshing state by the extraction force Fr. .

  That is, when the actual torque phase time t1 to t4 is longer than the target torque phase time, the start timing t2 of the direct clutch (friction-type transmission element) engagement progression speed decrease is delayed by extending the previous period TM1 and shortening the later period TM2. Then, by extending the use time of the rapid increase speed α and shortening the use time of the slow increase speed β, the first time TM1 and the second time TM2 are learned so that the actual torque phase time t1 to t4 becomes the target torque phase time. The first period TM1 and the second period TM2 are updated and changed to these learning values.

  Conversely, if the actual torque phase time t1 to t4 is shorter than the target torque phase time, the direct clutch (friction-type transmission element) engagement progress speed decrease start timing t2 is shortened to the previous period TM1 and extended to the later period TM2. Earlier, TM1 and later time TM2 so that the actual torque phase time t1 to t4 becomes the target torque phase time by shortening the use time of the rapid increase speed α and extending the use time of the slow increase speed β. Learning control is performed, and the first period TM1 and the second period TM2 are updated and changed to these learning values.

<Learning (6)>
Direct clutch (friction-type transmission element) engagement progress speed reduction start timing t2 is further instant t4 from this instant t2 when reduction brake R / B (engagement-type transmission element) is switched from the meshed state to the non-engaged state by the pulling force Fr. Learning control is performed as follows according to the actual late period t2 to t4.

  That is, when the actual late period t2 to t4 is longer than the target late period, the direct clutch (friction type transmission element) engagement progress speed decrease start timing t2 is delayed by extending the first period TM1 and shortening the second period TM2. The early period TM1 and the late period TM2 are learned and controlled so that the actual late period t2 to t4 become the target late period, and the previous period TM1 and the late period TM2 are updated and changed to these learning values.

  Conversely, if the actual late period t2 to t4 is shorter than the target late period, the direct clutch (friction type transmission element) engagement progression speed decrease start timing t2 is advanced by shortening the previous period TM1 and extending the latter period TM2. Thus, the learning period TM1 and the latter period time TM2 are subjected to learning control so that the actual latter period times t2 to t4 become the target later period time, and the previous period time TM1 and the latter period time TM2 are updated and changed to these learning values.

<Effect of Example>
According to the shift (upshift) control of this embodiment described above,
The direct clutch D / C (friction-type transmission element) is switched from the disengaged state to the engaged state more slowly in the second half of the instant t2 to t4 than in the first half of the instant t1 to t2, and the predetermined timing t3 of the second t2 to t4 The following effects are achieved by applying a pulling force Fr to the reduction brake R / B (engagement speed change element) and switching the reduction brake R / B (engagement speed change element) from the meshing state to the non-meshing state. Can be played.

  In other words, the switching of the direct clutch D / C (friction type transmission element) from the disengaged state to the engaged state is advanced prior to the reduction brake R / B (engaging type transmission element) switching from the meshing state to the non-meshing state. As a result, at the instant t4 when the transmission torque Tc of the reduction brake R / B (engagement type transmission element) is reduced, the reduction brake R / B (engagement type transmission element) is changed from the meshing state to the non-meshing state by the pulling force Fr. The corresponding shift is performed by switching.

Therefore, there is no time for both the reduction brake R / B (engagement type transmission element) and the direct clutch D / C (friction type transmission element) to be unable to transmit power, and therefore the automatic transmission 2 is upshifted. A neutral state where power cannot be transmitted does not occur, and it is possible to prevent the drive torque from becoming zero during shifting and causing a feeling of deceleration.
For the same reason, the input side rotation speed of the automatic transmission 2 is not temporarily increased, and a shift shock accompanying this input rotation change can be avoided.

In this embodiment, the direct clutch D / C (friction type transmission element) is switched from the disengaged state to the engaged state in the latter period t2 to t4 when the pulling force Fr is applied to the reduction brake R / B (engaging type transmission element). (The increase in the direct clutch transmission torque Tf) is gradually advanced as indicated by β, so that the reduction brake R / B (engagement type transmission element) corresponding to the state switching of the direct clutch D / C (friction type transmission element) The decrease in the transmission torque Tc can be made moderate.
For this reason, the reduction brake R / B (engagement type transmission element) is brought into the non-engagement state at the timing t3 when the transmission torque Tc of the reduction brake R / B (engagement type transmission element) has just decreased to a good value. Therefore, it is easy to control to apply the pulling force Fr.

  Therefore, the timing t4 for switching the reduction brake R / B (engagement speed change element) to the non-engagement state does not become inappropriate, and the automatic transmission 2 tends to be interlocked with a delay in this timing, and the torque pulling shock It is possible to avoid the problem relating to the deterioration of the shift quality, such as the occurrence of a shift shock and the occurrence of a large shift shock due to the temporary increase of the transmission input rotational speed due to the above timing being too early.

Moreover, in solving the problem, the direct clutch D / C (friction type speed change element) is released from the released state to the engaged state only in the latter period t2 to t4 when the pulling force Fr is applied to the reduction brake R / B (engagement type speed change element). The switching (increase in direct clutch transmission torque Tf) is gradually advanced as indicated by β, and the state switching speed of direct clutch D / C (friction type transmission element) (increase speed of direct clutch transmission torque Tf) during the previous period t1 to t2. ) To remain regular fast (α)
The direct clutch D / C (friction type speed change element) engagement progression speed β reduced as described above does not increase the shift time of the automatic transmission 2 beyond an allowable time in terms of shift quality, The slip time during shifting of the direct clutch D / C (friction type transmission element) is not made long enough to affect the durability of the direct clutch D / C (friction type transmission element).

In addition, in this embodiment, the direct clutch transmission torque, which is the speed at which the direct clutch D / C (friction type transmission element) is engaged, is obtained by the learning (1) to (6) in step S20 every time the upshift is completed. The timing t2 at which the rapid increase speed α and slow increase speed β of Tf and the engagement progress speed (increase speed of the direct clutch transmission torque Tf) of the direct clutch D / C (friction type transmission element) start to decrease, in other words, direct clutch transmission. The first and second periods TM1 and TM2 in which the torque Tf is rapidly increased at the speed α and slowly increased at the speed β are learned and controlled so that the actual torque phase times t1 to t4 and the actual latter time TM2 become the target times, α, β, To update TM1 and Tm2 respectively to the learning values and contribute to upshift control from the next time onwards,
The actual torque phase time t1 to t4 and the actual late time TM2 can always be kept at the target time, and the shift quality can be maintained at the desired high quality for a long time, and the direct clutch D / C (friction-type shift element) ) Can be prevented from slipping for a long time at the time of shifting, and the deterioration of its durability can be avoided.

<Other embodiments>
The direct clutch transmission torque Tf sudden increase speed α and slow increase speed β, and the direct clutch D / C (friction-type transmission element) engagement progress speed decrease start timing (direct clutch transmission torque Tf increase speed decrease start timing) The learning (1) to (6) described above for the first period TM1 and the second period TM2 for determining t2 do not necessarily have to be performed, but only one of them or a combination of arbitrary ones may be performed. Needless to say, in this case as well, it is needless to say that the above-mentioned effects can be achieved to some extent.

1 Motor (electric motor)
2 Automatic transmission
3 Final reduction gear set
4 Differential gear unit
5L, 5R left and right wheel shaft
11 Input shaft
12 Output shaft
13 Planetary gear type speed change mechanism
14 Sungear
15 Ring gear
16 Planetary pinion
17 Career
21 Transmission controller
22 Shift control information detection sensor group

Claims (8)

In an automatic transmission capable of shifting by an operation of switching the frictional transmission element from the released state to the engagement state and an operation of switching the engagement type transmission element from the meshing state to the non-meshing state by applying a pulling force,
Friction type transmission element switching speed control means for switching the friction type transmission element from the released state to the engaged state more slowly in the latter period than in the previous period;
By applying this means, a pulling force is applied to the engagement type transmission element from a predetermined timing at a later stage when the friction type transmission element is slowly switched from the release state to the engagement state, and the engagement type transmission element is brought into the non-engagement state. A shift control device for an automatic transmission, characterized by comprising engagement type shift element switching means for causing switching to a meshing state. In the shift control device of the automatic transmission according to claim 1,
The state switching speed from the loosely released state to the engaged state of the frictional speed change element in the latter period is the timing at which the engagement type speed change element is engaged with the engagement type speed change element at an appropriate timing. A shift control apparatus for an automatic transmission, characterized by a gradual state switching speed that can be controlled so as to be switched to a non-engagement state. The shift control device for an automatic transmission according to claim 1 or 2,
The frictional transmission element switching speed control means starts from the start of the operation of switching the frictional transmission element from the released state to the engaged state until the switching from the meshing state to the non-meshing state of the engagement type transmission element occurs. A shift control apparatus for an automatic transmission, characterized by changing a gradual state switching speed of the frictional transmission element in the latter period so that the time becomes a target time. In the shift control device for an automatic transmission according to any one of claims 1 to 3,
The frictional transmission element switching speed control means switches from the frictional transmission element state switching speed decrease start timing to start to decrease the state switching speed of the frictional transmission element from the meshing state of the engagement transmission element to the non-engagement state. A shift control apparatus for an automatic transmission, characterized in that the gradual state switching speed of the frictional transmission element in the latter period is changed so that the time until switching occurs becomes a target time. In the shift control device for an automatic transmission according to any one of claims 1 to 4,
The frictional transmission element switching speed control means starts from the start of the operation of switching the frictional transmission element from the released state to the engaged state until the switching from the meshing state to the non-meshing state of the engagement type transmission element occurs. A speed change control device for an automatic transmission, wherein the speed change speed of the friction type speed change element in the previous period is changed so that the time becomes a target time. In the shift control device for an automatic transmission according to any one of claims 1 to 5,
The frictional transmission element switching speed control means switches from the frictional transmission element state switching speed decrease start timing to start to decrease the state switching speed of the frictional transmission element from the meshing state of the engagement transmission element to the non-engagement state. A speed change control device for an automatic transmission, wherein the speed change speed of the friction type speed change element in the previous period is changed so that the time until the change occurs becomes a target time. In the shift control device for an automatic transmission according to any one of claims 1 to 6,
The frictional transmission element switching speed control means starts from the start of the operation of switching the frictional transmission element from the released state to the engaged state until the switching from the meshing state to the non-meshing state of the engagement type transmission element occurs. A shift control apparatus for an automatic transmission, characterized in that the frictional transmission element state switching speed reduction start timing is changed so as to start reducing the state switching speed of the frictional transmission element so that the time becomes a target time. In the shift control device for an automatic transmission according to any one of claims 1 to 7,
The frictional transmission element switching speed control means switches from the frictional transmission element state switching speed decrease start timing to start to decrease the state switching speed of the frictional transmission element from the meshing state of the engagement transmission element to the non-engagement state. A shift control apparatus for an automatic transmission, characterized in that the frictional speed change element state switching speed reduction start timing is changed so that the time until switching occurs becomes a target time.

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