JP3033566B1 - Transmission control device for automatic transmission - Google Patents

Abstract

To improve the shift quality by performing a shift control such that a shock caused by the release of the foot and a shift shock caused by an actual shift are absorbed during an upshift from a high throttle opening. A controller for controlling a shift of an automatic transmission includes a signal from a throttle opening sensor for detecting a throttle opening TVO of the engine, a signal from an oil temperature sensor for detecting an oil temperature, and the like. Is input and a predetermined control program is executed to determine whether or not the upshift is a foot release from a high throttle opening at the time of upshift determination. In addition, hydraulic control is performed to increase the hydraulic pressure to the friction elements involved in the shift more quickly than in the case of an upshift from a low throttle opening.

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, which improves shift quality during an upshift from a high throttle opening.

[0002]

2. Description of the Related Art As a prior art of a shift control device for an automatic transmission, which improves the shift quality at the time of a foot-off upshift, there is one disclosed in, for example, JP-A-10-47467. In this prior art, at the time of a foot release upshift, an actual gearshift accompanied by a change in input speed is performed after the transmission output shaft torque turns negative.

[0003] Japanese Patent Application Laid-Open No. 10-61757 discloses a technique for improving a shift quality by changing a hydraulic pressure to a friction element involved in the upshift based on a gear ratio constantly monitored. Have been.

[0004]

However, in each of the above-mentioned prior arts, even if the upshift is the upshift from a high throttle opening, the upshift is a downshift from a low throttle opening. However, since the same shift control is performed, the longitudinal acceleration change accompanying the foot release during an upshift from a high throttle opening increases, and the input is performed after a shock caused by this large longitudinal acceleration change occurs. Since a shift shock occurs due to an actual shift accompanied by a change in the number of revolutions, a total of two shocks occur, which is not preferable.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem by performing a special shift control for suppressing the occurrence of a shift shock only when an upshift is performed from a high throttle opening. .

[0006]

For this purpose, a first invention according to claim 1 comprises a throttle opening detecting means for detecting a throttle opening, and an upshift determining means for determining the presence or absence of an upshift. An upshift determination means for determining whether the upshift is a foot release upshift from a high throttle opening at the time of the upshift determination; and a low throttle opening when the upshift is a high release opening from a high throttle opening. And a hydraulic control means for performing a hydraulic control for accelerating an increase in the hydraulic pressure to the friction element involved in the speed change compared to the case of the upshift from the foot.

According to a second aspect of the present invention, in the first aspect, in the case of a foot release upshift from a high throttle opening, an increase in oil pressure to the friction element during shifting is started from the start of the shifting. Control in accordance with the elapsed time of, and in the case of a foot release upshift from a low throttle opening, the increase in oil pressure to the friction element during shifting is controlled in accordance with the progress of the shift. And

According to a third aspect of the present invention, in the first aspect of the invention, in the case of a foot release upshift from a high throttle opening, the actual shift is performed while the transmission output shaft torque is positive, and In the case of an upshift with the foot released from the throttle opening, the actual shift is performed after the transmission output shaft torque has turned negative.

A fourth invention according to claim 4 is the first invention.
In the third invention, the foot release upshift determination means is configured to determine that the throttle opening at a point in time preceding the upshift determination by a first predetermined time is equal to or greater than a first predetermined value, and Only when the throttle opening falls below a second predetermined value set to a value smaller than the first predetermined value until the predetermined time elapses, the upshift from the high throttle opening It is characterized in that it is determined that the foot release is an upshift.

[0010]

In the first aspect of the invention, when the upshift determining means determines that the shift is an upshift, the foot release upshift determining means determines whether the shift is an upshift based on the throttle opening detected by the throttle opening detecting means. It is determined whether the upshift is a foot release upshift from a high throttle opening. Based on this determination, the hydraulic control means
In the case where the upshift is a foot release upshift from a high throttle opening, the hydraulic pressure for accelerating the rise of the hydraulic pressure to the friction elements involved in the shift is higher than in the case of a foot release upshift from a low throttle opening. Perform control.

Since the actual shift timing is advanced by the hydraulic control for increasing the hydraulic pressure, the time interval between the shock due to the release of the foot and the shift shock due to the actual shift is reduced. Here, for example, by appropriately setting the degree of increasing the hydraulic pressure so that the shocks overlap each other, the longitudinal acceleration acts in the negative direction for the shock due to the release of the foot, and the longitudinal acceleration increases in the forward shock for the actual shift. Acting in the direction, one of the shocks will be absorbed by the other. Therefore, the generated shift shock is reduced,
Shift quality is improved.

[0012] In the second invention, the shift control device for the automatic transmission, when the foot is upshifted from a low throttle opening, is similar to the prior art of Japanese Patent Application Laid-Open No. 10-61757. The increase in oil pressure to the friction element is controlled in accordance with the progress of the shift (for example, a change in gear ratio or a change in input speed).
The situation cannot be covered by the prior art of No. 57,
In the case of a foot release upshift from a high throttle opening, consideration is given to the fact that the shift shock is absorbed by the first invention and it is not necessary to finely control the hydraulic pressure to the friction elements involved in the shift based on the gear ratio. Then, the increase of the hydraulic pressure to the friction element during the shift is controlled according to the elapsed time from the start of the shift. This hydraulic control has to realize an early shift so that a shift shock due to the actual shift occurs during the change in the longitudinal acceleration due to the release of the foot, so that a simple timer control can be performed, and the control is simplified, The actual shift can be performed quickly.

In the third aspect of the invention, the shift control device for the automatic transmission, when the foot is upshifted from a low throttle opening, outputs the output shaft torque in the same manner as in the prior art disclosed in Japanese Patent Application Laid-Open No. 10-47467. Is turned negative, actual transmission is performed. However, in the case of an upshift from a high throttle opening, which is a situation that cannot be covered by the prior art disclosed in JP-A-10-47467, the transmission output shaft torque is increased. The actual speed change is performed while is positive. Due to the actual shift while the transmission output shaft torque is positive, the time interval between the shock due to the release of the foot and the shift shock due to the actual shift is reduced.
The function of absorbing the shocks of the first aspect can be realized. In addition, while the transmission output shaft torque is on the plus side, the actual gearshift with the rotation speed change and the transmission output shaft torque change is performed, so that the zero crossing of the transmission output shaft torque (change between plus and minus) ) Does not occur. Therefore, the generated shift shock is reduced, and the shift quality is improved.

According to a fourth aspect of the present invention, there is provided a shift control device for an automatic transmission, wherein the upshift of the foot release according to the first to third aspects is (1) the throttle opening at a point in time when the upshift is determined by going back a first predetermined time. The degree is greater than or equal to a first predetermined value;
(2) that the throttle opening has become equal to or less than a second predetermined value set to a value smaller than the first predetermined value during a period from when the upshift is determined to when a second predetermined time has elapsed.
Only when the two conditions are satisfied, it is determined that the “upshift from a high throttle opening” is performed. Therefore, the hydraulic control for accelerating the hydraulic pressure increase of the first invention is effective during the upshift with the release of the throttle. It is possible to reliably detect "upshift from foot release from throttle opening".

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a power train of a vehicle including a shift control device for an automatic transmission according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an engine, and 2 denotes an automatic transmission, which constitutes a power train of a vehicle by tandem coupling. The output of the engine 1 is adjusted by a throttle valve 4 whose opening increases from fully closed to fully open as the accelerator pedal 3 is depressed in conjunction with an accelerator pedal 3 operated by the driver. The engine output is automatically transmitted through a torque converter T / C. It is assumed that the signal is input to the transmission 2.

The automatic transmission 2 is a working hydraulic pressure (a hydraulic pressure in this embodiment) to be supplied to friction elements such as a hydraulic operating clutch and a hydraulic operating brake that determine a power transmission path (gear stage) of the gear transmission system. Therefore, the hydraulic pressure duty solenoids 6, 7, 8 are provided in the control valve 5 for shifting control by the number of the friction elements.

These hydraulic pressure duty solenoids 6,
7 and 8, the hydraulic pressure, which is the hydraulic fluid pressure of the corresponding friction element, is individually duty-controlled to selectively engage the friction element to bring the automatic transmission 2 into a state in which a predetermined gear position is selected. To get. And automatic transmission 2
Shifts and outputs the engine power at a gear ratio corresponding to the selected gear position. In the following description, it is assumed that the automatic transmission 2 is configured as a five-speed automatic transmission having first to fifth speeds.

Driving data for duty solenoids 6, 7, 8
Utility is determined by the controller 11, and this controller
The roller has a throttle opening TV of the throttle valve 4.
A signal from the throttle opening sensor 12 for detecting O,
Output speed N of automatic transmission 2 _oDetect output rotation center
And the engine speed N_eTo detect
The signal from the engine rotation sensor 14 and the input of the automatic transmission 2
Power speed N_iFrom the input rotation sensor 15 for detecting
And an oil temperature sensor 1 for detecting a hydraulic oil temperature T of the automatic transmission 2
6 are input. The throttle
Throttle opening TVO detected by opening sensor 12
Is stored in a memory (not shown) in association with the passage of time.
Shall be used.

The controller 11 executes the control programs shown in FIGS. 2 and 3 based on the various kinds of input information to control the shift of the automatic transmission 2.

In the control program of FIG. 2 which is started only when an upshift is performed (not started when there is no downshift or no shift), first in step 51,
Perform upshift determination. The upshift determination, for example with reference to the shift pattern (not shown) based on the vehicle speed VSP and throttle opening TVO obtained from the transmission output speed N _o, the upshift lines when traversed upshift line in the shift pattern Is determined to be an upshift corresponding to. At this time, the upshift is performed in D range 1 → 2, 2 → 3, 3 → 4, 4 range 1 → 2,2
→ 3,3 → 4,3 range 1 → 2,2 → 3,2 range 1 →
If it is any of the two upshifts, the control proceeds to step 52. If the upshift is the D range 4 → 5 or the 1 range 1 → 2 upshift, the control proceeds to step 59 to perform the basic upshift. Execute control logic. The basic upshift control logic detects the start of the inertia phase by detecting the start of a change in the gear ratio and the engine speed, and performs a fixed shelf pressure control on the engagement side during the inertia phase, or after the shift is completed. Or control for shifting to the maximum pressure by detecting that the gear ratio or the engine speed has been reached (for details of the basic upshift control logic, see, for example, Japanese Patent Application Laid-Open No. 10-61757). thing).

In steps 52 and 53, the upshift is a foot release upshift from a high throttle opening (hereinafter referred to as a high opening foot release upshift) or a foot release upshift from a low throttle opening. (Hereinafter referred to as a low-opening-foot-release upshift) or another upshift.

That is, first, at step 52, the throttle opening TVO at the instant t1 which is a first predetermined time TM1 preceding the upshift determination instant t2 is equal to or higher than the high opening determination reference value (first predetermined value) TVO _HIGH. It is determined whether or not TVO ≧ TVO _HIGH . If TVO <TVO _HIGH , the control proceeds to step 59.
Proceed to In step 53, the upshift determination instant t
2 until the second predetermined time TM2 elapses, the throttle opening TVO departs from the reference value (second predetermined value)
TVO _LOW (however, TVO _HIGH > TVO _LOW )
It is determined whether or not the following conditions are satisfied. If TVO ≦ TVO _LOW , the control immediately proceeds to step 54 without waiting for the predetermined time TM2 to elapse, and if TVO> TVO _LOW , the control proceeds to step 59. . The predetermined time T
It is assumed that constant values are used as M1 and TM2, the high opening degree determination reference value TVO _HIGH and the foot release determination reference value TVO _LOW regardless of the shift pattern.

As described above, it is determined that the upshift is a high-open-foot-upshift only when the determinations in steps 52 and 53 are both YES. In this case, the control is shifted from step 54 onward. Proceed to If the determination in step 52 is NO, this is a low opening upshift (including a normal low opening upshift and a foot release low opening upshift), and the determination in step 53 is NO. The above case is the case of a non-lifting upshift from a high throttle opening, and neither is the control target of the shift control in the present embodiment. Therefore, the basic upshift logic is executed as described above.

In step 54, it is determined whether or not the transmission working oil temperature T is equal to or higher than the permission oil temperature Ts. If the permission condition that satisfies T ≧ Ts is satisfied, the control proceeds to step 55, where T <T
When the permission condition that s is not satisfied, the control proceeds to step 59. Then, in step 55, the control logic shifts from the basic upshift logic at the start to the "high opening foot release upshift logic" specially provided in the present embodiment. Therefore, a high opening degree foot release upshift logic is applied to the following foot release upshift.

In the next step 56, the upshift is performed when the D range 3 → 4, the 4 range 3 → 4, the 3 range 2
→ 3, 2 Range 1 → 2 to determine whether it corresponds to any of. If the determination is other than the above, the control proceeds to step 57, where D range 3 → 4, 4 range 3 →
If it is one of 4, 3 and 2 and 3 and 2 and 1 and 2, respectively, the control proceeds to step 58 to execute the upshift. When step 58 is executed, since there is no further upshift in the range, the current control is terminated.

In step 57, the upshift is performed when the D range 1 → 2, the 4 range 1 → 2, and the 3 range 1 → 2
Judge whether it corresponds to any of the above, D range 1 → 2,
If it is any of the four ranges 1 → 2 and three ranges 1 → 2, the control proceeds to step 61 and subsequent steps in FIG. 3; otherwise (ie, any of the D ranges 2 → 3 and the four ranges 2 → 3) ), The control proceeds to step 65 onward in FIG.

In step 61 in FIG. 3 in which control is performed in any of the D range 1 → 2, the 4 range 1 → 2, and the 3 range 1 → 2 shift, the throttle opening TVO is set to the foot release determination reference value TVO _LOW . It is determined whether or not the vehicle has crossed the 2 → 3 shift line until the vehicle arrives. If it is determined that the vehicle does not cross the 2 → 3 shift line in this determination, the control proceeds to step 62, and
→ Upshift two feet apart (D range 1 → 2, 4 range 1
→ 2, 3 range 1 → 2 shift), and if the vehicle has crossed, control proceeds to step 63.

In step 63, it is determined whether or not there are three ranges.
Range 1 → 2, 2 → 3 feet Upshift is continuously executed. On the other hand, if it is determined in step 63 that the range is other than 3 ranges (D range and 4 range in this case), the control is performed together with the case of NO in step 57 in FIG.
Proceed to 5. In step 65, the throttle opening TVO
3 until it reaches the foot release judgment reference value TVO _LOW
→ It is determined whether the vehicle has crossed the 4-shift line. In this determination, if the vehicle does not cross the 3 → 4 shift line, the control proceeds to step 66, and if it does, the control proceeds to step 67.

In step 66, a different shift is executed according to the route that reaches step 66. That is,
When step 66 has been reached from YES in step 57 of FIG. 2, since the 1 → 2 shift has already been determined, the D range 1 → 2, 2 → 3 or the 4 range 1 → 2,2
→ If the upshift is continuously executed with three feet apart, and the process reaches step 66 from N0 of step 57 in FIG.
Execute D range 2 → 3 or 4 range 2 → 3 feet upshift.

In step 67, a different shift is executed according to the route that reaches step 67. That is,
When step 67 has been reached from YES in step 57 in FIG. 2, since the 1 → 2 shift has already been determined, the D range 1 → 2, 2 → 3, 3 → 4 or the 4 range 1
→ 2,2 → 3,3 → 4 The upshift is continuously executed and if the step 67 is reached from N0 of step 57 in FIG. 2, the D range 2 → 3,3 → 4 or 4 range Perform an upshift with 2 → 3, 3 → 4 foot separation.

Next, the operation of the present embodiment will be described with reference to FIG. When the upshift is determined at the instant t2 in FIG. 4, the execution of the step 52 in FIG. 2 causes the throttle opening TVO at the instant t1 which is a predetermined time TM1 earlier than the instant t2.
Is greater than or equal to the high opening determination reference value TVO _HIGH . This determination becomes NO in, for example, (1) an upshift from a throttle opening that is not so high, or (2) an upshift with the foot slowly released.

[0032] Here, since there is no time margin until the zero crossing is the transmission output shaft torque T ₀ from upshift determination time t2 in the case of (1), transmission output shaft torque T
It is difficult to start the engagement of the friction element while ₀ is on the plus side, and in the cases of (1) and (2), the shift is started early because the longitudinal acceleration change due to the release of the foot is small. In consideration of the fact that the shift shock absorbing effect that can be obtained is also small, in the cases (1) and (2), the “high opening foot release upshift logic” is not applied, and the transmission output shaft torque T _{0 is} conventionally used. The basic upshift logic for starting the engagement of the friction element after the value becomes negative is applied.

Further, by executing step 53 in FIG. 2, it is determined whether or not the throttle opening TVO has become equal to or less than the reference value TVO _{LOW for a} predetermined time TM2 from the instant t2 when the upshift is determined. Is done. This determination becomes NO, for example, in the case of (3) an upshift that is not complete release of the foot, or in the case of (4) an upshift in which the foot is slowly released. In these cases as well, for the same reason as described above, the “high opening foot release upshift logic” is not applied, and the transmission output shaft torque T _{0 is} conventionally used.
The basic upshift logic for starting the engagement of the friction element after the value becomes negative is applied.

As described above, only in the case of the upshift from the high throttle opening, the "high opening foot release upshift logic" is applied after the instant t23 in FIG. 4 by executing step 55 in FIG. From step 5 in FIG.
8. In the foot release upshift in steps 62, 64, 66, and 67 in FIG. 3, hydraulic control corresponding to "high opening degree foot release upshift logic" is executed.

In the hydraulic control corresponding to the "high opening foot release upshift logic", the increase in the hydraulic pressure supplied to the friction element is made faster than in the case of the foot release upshift from a low throttle opening. . That is, FIG.
When the release is determined at instant t23, the initial value at the start of the command oil pressure high opening foot upshift logic is set to the basic upshift logic command oil pressure indicated by the dotted line in the figure. After abruptly dropping to the value, the value suddenly rises to the illustrated constant shelf pressure command value at the time TM3, and the value is maintained for TM4. Then, as shown in the drawing, the pressure increases at a predetermined slope during TM5, and then changes to the maximum pressure. In the above hydraulic control, the increase in the hydraulic pressure is equal to the upshift determination instant t2.
Is controlled in accordance with the elapsed time from the start of the shift, but the increase in the hydraulic pressure is generally higher than the basic upshift logic that controls the increase in the hydraulic pressure in accordance with the progress of the shift (change in gear ratio, change in engine speed, etc.) I try to advance the timing.

When the hydraulic control for increasing the hydraulic pressure is performed in this manner, the actual shift timing is advanced, and the time interval between the shock due to the release of the foot and the shift shock due to the actual shift is reduced. At this time, by making these shocks overlap, the shock due to the release of the foot acts in the direction of decreasing the longitudinal acceleration, and the shift shock due to the actual shift acts in the direction of increasing the longitudinal acceleration, so that one of the shocks acts on the other. Absorbed. In addition, while the transmission output shaft torque is on the plus side, the actual gearshift with the rotation speed change and the transmission output shaft torque change is performed, so that the zero crossing of the transmission output shaft torque (change between plus and minus) ) Does not occur. Therefore, the generated shift shock is reduced, and the shift quality is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a power train of a vehicle including a shift control device for an automatic transmission according to a first embodiment of the present invention.

FIG. 2 is a control program showing shift control of the automatic transmission according to the first embodiment.

FIG. 3 is a control program showing shift control of the automatic transmission according to the first embodiment.

FIGS. 4A and 4B are diagrams for explaining the operation of the first embodiment.

[Explanation of symbols]

 Reference Signs List 1 engine 2 automatic transmission 3 accelerator pedal 4 throttle valve 5 control valve 6,7,8 hydraulic fluid duty solenoid 11 controller 12 throttle opening sensor 13 output rotation sensor 14 engine rotation sensor 15 input rotation sensor 16 oil temperature sensor

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16H 59/00-61/24

Claims (4)

(57) [Claims] 1. A throttle opening detecting means for detecting a throttle opening, an upshift determining means for determining the presence or absence of an upshift, and determining whether the upshift is a foot release upshift from a high throttle opening when the upshift is determined. A lift-off shift determining means for determining whether or not the oil pressure is applied to the friction elements involved in the shift in the case of a lift-off upshift from a high throttle opening, compared to the case of a foot-off upshift from a low throttle opening; A shift control device for an automatic transmission, comprising: a hydraulic control means for performing a hydraulic control for accelerating a rise of the speed. 2. In the case of a foot-release upshift from a high throttle opening, an increase in oil pressure to the friction element during a shift is controlled in accordance with an elapsed time from the start of the shift, and a shift from a low throttle opening is controlled. In the case of a foot release upshift, an increase in oil pressure to the friction element during a shift is controlled in accordance with the progress of the shift.
The shift control device for an automatic transmission according to claim 1. 3. In the case of a foot release upshift from a high throttle opening, actual transmission is performed while the transmission output shaft torque is positive, and in the case of a foot release upshift from a low throttle opening, the transmission output is increased. 2. The shift control device for an automatic transmission according to claim 1, wherein the actual shift is performed after the shaft torque turns negative. 4. The method according to claim 1, wherein the foot release upshift determining means is configured to determine that the throttle opening at a point in time preceding the upshift determination by a first predetermined time is equal to or greater than a first predetermined value, and that the throttle opening is determined by a second shift from the upshift determination. Only when the throttle opening falls below a second predetermined value set to a value smaller than the first predetermined value until the predetermined time elapses, the upshift from the high throttle opening The shift control device for an automatic transmission according to any one of claims 1 to 3, wherein the shift control is determined to be a foot release upshift.