JPH0565952A - Shift controller of automatic transmission for vehicle - Google Patents

Abstract

PURPOSE:To keep off any shift shock without complecating the control at the time when it is shifted to a neutral range from the forward one. CONSTITUTION:A fact that car speed is shifted to a neutral range from the forward one by a range selector 4 is detected by a range detecting means 5, and at that time, if the car speed detected by a car speed detecting means 6 is higher than the preset one, a shift part control means 7 maintaines a sub- shift part 2 to a shift speed at the forward range just before being shifted to the neutral range. In this connection, when the car speed is less than the preset one, this sub-shift part 2 is made so as to be constituted to the higher speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a shift in an automatic transmission for a vehicle, and more particularly to a main transmission unit capable of setting a reverse gear and a plurality of forward gears and at least two high and low gears. The present invention relates to a shift control device for an automatic transmission that includes an auxiliary shift unit that can shift gears.

[0002]

2. Description of the Related Art An automatic transmission having a main transmission portion and an auxiliary transmission portion as described above has a gear ratio that is set by setting the auxiliary transmission portion at a high speed while the main transmission portion is set at a maximum speed. "1"
The following so-called overdrive stage can be set, fuel efficiency can be improved, and quietness can be improved. On the other hand, in order to set a predetermined shift speed, on the other hand, a so-called simultaneous shift in which each shift portion is shifted at the same time occurs, and in particular, any one shift portion is upshifted and the other shift portion is downshifted. In the case of the simultaneous shift, the shift shock may be large, and complicated shift control is required to prevent the shift shock.

Therefore, the applicant of the present invention has proposed a shift control method for reducing the shift shock in the above-mentioned automatic transmission in the so-called simultaneous shift pattern.
Already proposed by No. 71554. Specifically, when setting the 2nd speed (1.5th speed) as the gear position for starting when shifting from the neutral range to the drive range, the speed change sets the main transmission portion to the 1st speed,
And since it is a simultaneous shift that sets the auxiliary shift unit to a high speed stage,
This is a method in which the auxiliary transmission unit is set to the high speed stage in advance. According to this method, the target second speed (1.5th speed) can be set immediately by engaging the forward clutch of the main transmission portion, and the gear ratio can be set lower than that of the first speed, which is the lowest speed stage. Is small, the shift shock can be reduced also in this respect.

[0004]

SUMMARY OF THE INVENTION In an automatic transmission having a main transmission section and an auxiliary transmission section, in order to reduce shift shock as described above, the auxiliary transmission section is set to a high speed stage as a shift stage at the time of starting. It may be preferable to set the shift speed to be set, and the gear ratio of the reverse gear may become excessive depending on the configuration of the main shift portion. Will be set to. Therefore, in this type of automatic transmission, in the neutral range and the parking range, which are the ranges in which the stopped state is maintained, the sub-transmission unit engages its friction engagement device to establish the high-speed stage state as in the method of the invention described above. Will be.

However, since the shift to the neutral range is performed by an artificial operation, it may be switched to the neutral range even while the vehicle is running. In such a case, in the automatic transmission for performing the shift control described above. Means that the subtransmission unit is set to the high speed stage. Therefore, if the shift speed immediately before switching to the neutral range is a shift speed that is set with the sub-transmission unit at a low speed, the main shift unit is moved from the predetermined forward speed to the neutral position with the manual shift to the neutral range. In addition to switching to the state, the auxiliary transmission unit is switched from the low speed stage to the high speed stage.

[0006] To shift to such a neutral state,
In order to prevent a shift shock, it is necessary to first shift the main transmission unit to a neutral state and then switch the sub-transmission unit to a high speed stage, but the friction transmission engaged to bring the main transmission unit to a predetermined forward stage. The time required to release the coupling device is not always constant because it is affected by centrifugal hydraulic pressure etc. due to the rotation of the friction engagement device, and the auxiliary transmission unit is engaged in order to make it a high speed stage. The time required to engage the friction engagement device is not always constant due to various factors. Therefore, in particular, when the main transmission section is set to the neutral state during high-speed traveling and the sub-transmission section is switched from the low speed stage to the high speed stage, in order to prevent shift shock,
You have to perform complicated sequence control, etc.,
Further, if the control becomes improper, there is a problem that a large shift shock occurs.

The present invention has been made in view of the above circumstances, and provides a shift control device capable of reliably preventing a shift shock without complicating the control when switching to the neutral range during traveling. The purpose is to do.

[0008]

The present invention achieves the above object by adopting the configuration shown in FIG. That is, according to the present invention, the main transmission unit 1 set to a plurality of forward gears and the reverse gear stage and the sub transmission unit 2 set to at least two high and low gears are connected in series, and power is transmitted to the output shaft 3. A range selecting device 4 for manually selecting a plurality of ranges including a neutral range and a forward range for setting the forward speed is provided, and the starting speed is set to the auxiliary speed change section 2 at the high speed and the main speed change section 1 is set. In a shift control device for an automatic transmission for a vehicle configured to be set to a predetermined low speed stage, a range detecting means 5 for detecting a range selected by the range selecting device 4, and a vehicle speed detecting means 6 for detecting a vehicle speed. , If the vehicle speed when the auxiliary transmission section 2 is switched from the forward range to the neutral range is higher than a predetermined vehicle speed, the forward range immediately before switching to the neutral range is set. Maintaining the gear position, and when the forward range of the following vehicle the vehicle speed is predetermined when switched to the neutral range to a high speed variable transmission unit control means 7
It is characterized by having and.

[0009]

In the automatic transmission according to the present invention, the main transmission unit 1 is set to any forward speed or reverse speed, and the auxiliary transmission unit 2 is set.
Is set to either a high or low speed, the overall speed of the automatic transmission is set. Further, the starting shift speed during forward movement is set by setting the main transmission unit 1 to a predetermined low speed stage and the sub transmission unit 2 to a high speed stage. Therefore, at least when the vehicle is in neutral immediately before starting, the subtransmission unit 2 is set to the high speed stage. A range such as a neutral range or a forward range is selected by manually operating the range selection device 4. When the range detecting means 5 detects the switching from the forward range to the neutral range by the range selecting device 4, the speed change part controlling means 7 causes the speed detecting means 6 to detect the vehicle speed according to the vehicle speed.
The sub transmission unit 2 is controlled as follows. That is, if the detected vehicle speed is higher than the predetermined vehicle speed, the auxiliary transmission unit 2 is maintained at the gear position in the forward range immediately before switching to the neutral range. On the other hand, if the detected vehicle speed is equal to or lower than the predetermined vehicle speed, the auxiliary transmission unit 2 is set to the high speed stage. The neutral state of the automatic transmission as a whole is achieved by setting the main transmission unit 1 in the neutral state. Therefore, when the forward range is switched to the neutral range at a high speed, the auxiliary transmission section 2 does not perform gear shifting and only the main transmission section 1 brings the neutral state. Therefore, control for switching to the neutral state is easy, and There is no risk of gear shift shock.

[0010]

2 is a block diagram showing an embodiment of the present invention, in which an automatic transmission 10 includes a torque converter 11, a sub-transmission unit 12 and , And a main transmission unit 13. Sub transmission unit 1
Reference numeral 2 denotes a speed change unit for overdrive, which is configured to perform two speed changes, a high speed stage and a low speed stage, and the main transmission unit 13 sets a plurality of forward and reverse stages. It is like this. Specific examples of each of the transmission units 12 and 13 will be described later.

The gear shifting in each gear shifting portion 12, 13 is performed by appropriately engaging or disengaging a friction engagement device such as a clutch or a brake, and a hydraulic control device 1 for that purpose.
4 are provided. Switching between the supply and discharge of the hydraulic pressure by the hydraulic control device 14 is performed by the first to fourth four solenoid valves 15, 16, 17, and 18. Of these, the first solenoid valve 15 is the auxiliary shift gear. The switching between the high speed stage (high) and the low speed stage (low) in the section 12 is performed. The second solenoid valve 1
Reference numeral 6 denotes a shift between the first speed and the second speed in the main shift section 13, the third solenoid valve 17 performs a shift between the second speed and the third speed, and the fourth solenoid valve 18 is the third speed. Speed and fourth
It is designed to carry out speed change.

An electronic control unit (ECU) 19 for controlling each solenoid valve described above is provided with a central processing unit 20, a storage unit 21 and an input / output interface 22, and each transmission unit is based on an input signal. The shift control of 12 and 13 is performed. That is, the electronic control unit 19 is provided with a shift position signal Sp corresponding to a position selected by the shift lever 23 such as a parking (P) range, a reverse (R) range, a neutral (N) range or a drive (D) range.
A signal corresponding to the vehicle speed V, a signal corresponding to the throttle opening θ,
Running mode signal according to N (normal) mode or P (power) mode, signal according to engine water temperature Tw,
A signal such as a signal corresponding to the engine speed Ne is input. Then, the vehicle speed V, the throttle opening θ, and a shift map (shift diagram) corresponding to the selected traveling mode
The first to fourth solenoid valves 15, 1 to 1 are selected so as to achieve the selected shift speed.
A signal is output to any one of the eight.

A specific example of the automatic transmission 10 described above is shown in a skeleton diagram in FIG. The automatic transmission 10 shown here
The torque converter 11 has a lockup clutch Lc.
Is provided between a front cover 27 integrated with the pump impeller 26 and a member (hub) 29 to which a turbine runner 28 is integrally attached. The engine crankshaft (not shown) is the front cover 2
The input shaft 30, which is connected to 7 and to which the turbine runner 28 is connected, is connected to a carrier 32 of an overdrive planetary gear mechanism 31 that constitutes the auxiliary transmission unit 12. A multi-plate clutch C0 and a one-way clutch F0 are provided between the carrier 32 and the sun gear 33 in the planetary gear mechanism 31. The one-way clutch F0 is adapted to be engaged when the sun gear 33 rotates forward relative to the carrier 32 (rotates in the rotational direction of the input shaft 30). Further, a multi-plate brake B0 for selectively stopping the rotation of the sun gear 33 is provided. The ring gear 34, which is an output element of the sub transmission unit 12, is connected to the intermediate shaft 35, which is an input element of the main transmission unit 13. Therefore, in the sub-transmission unit 12, the entire planetary gear mechanism 31 integrally rotates when the multi-plate clutch C0 or the one-way clutch F0 is engaged.
Rotates at the same speed as the input shaft 30, and becomes a low speed stage. Further, in the state where the brake B0 is engaged and the rotation of the sun gear 33 is stopped, the ring gear 34 is accelerated with respect to the input shaft 30 to rotate in the forward direction, and the high speed stage is established.

On the other hand, the main transmission section 13 is provided with three sets of planetary gear mechanisms 40, 50, 60, and their rotary elements are connected as follows. That is, the sun gear 41 of the first planetary gear mechanism 40 and the sun gear 51 of the second planetary gear mechanism 50 are integrally connected to each other, and the ring gear 43 of the first planetary gear mechanism 40 and the carrier 52 of the second planetary gear mechanism 50 are connected. The third planetary gear mechanism 60 and the carrier 62 are coupled to each other, and the carrier 62 is coupled to the output shaft 70. Further, the ring gear 53 of the second planetary gear mechanism 50 is connected to the sun gear 61 of the third planetary gear mechanism 60.

In the gear train of the main transmission unit 13, it is possible to set a reverse gear and four gears on the forward side, and clutches and brakes therefor are provided as follows. First, the clutch will be described. The ring gear 53 and the third gear of the second planetary gear mechanism 50 which are connected to each other.
A first clutch C1 is provided between the sun gear 61 of the planetary gear mechanism 60 and the intermediate shaft 35, and the sun gear 41 of the first planetary gear mechanism 40 and the sun gear 51 and the intermediate shaft of the second planetary gear mechanism 50 are connected to each other. A second clutch C2 is provided between the first clutch 35 and the second clutch C2.

Next, the brake will be described. The first brake B1 is a band brake, and the sun gears 41 and 5 of the first planetary gear mechanism 40 and the second planetary gear mechanism 50 are used.
It is arranged to stop the rotation of 1. Further, between the sun gears 41, 51 and the casing 71, the first
The one-way clutch F1 and the second brake B2, which is a multi-disc brake, are arranged in series. In the first one-way clutch F1, the sun gears 41 and 51 rotate in the reverse direction (in the direction opposite to the rotation direction of the input shaft 35). It is designed to engage when trying to rotate. Third brake B, which is a multi-disc brake
3 is provided between the carrier 42 of the first planetary gear mechanism 40 and the casing 71. As a brake for stopping the rotation of the ring gear 63 of the third planetary gear mechanism 60, a fourth brake B4, which is a multi-disc brake, and a second one-way clutch F2 are arranged in parallel between the casing 71. The second one-way clutch F2 is used for the ring gear 6
3 is adapted to engage when it tries to rotate in the reverse direction.

In the above-described automatic transmission 10, the sub transmission portion 12 can switch between high and low two stages, and the main transmission portion 13 can perform four shifts on the forward side, so that the vehicle can move backward. It is possible to shift gears between eight gears and eight forward gears, and FIG. 4 shows an engagement operation table of each clutch and brake for setting these gears. In FIG. 4, a circle indicates an engaged state, a circle indicates an engaged state during engine braking, and a blank indicates a released state.

The shift control device shown in FIG. 2 is provided with a plurality of shift maps as storage contents of the storage device 21,
Among them, as a shift map used in the D range,
A shift map having different shift stages including a plurality of shift stages set according to the vehicle speed V and the throttle opening θ is provided. An example of the gear train is shown in FIGS. 5 and 6. The gear train (provisionally referred to as A gear train) shown in FIG.
Of the eight gears shown in FIG. 4, 1st, 2nd, 3rd, 4
It is a gear train consisting of th and 5th gears and is set by setting the sub-transmission unit 12 to the low gear (low) except for the fifth gear (5th). The gear train shown in FIG. 6 (provisionally referred to as the B gear train) is the first gear of the eight gears shown in FIG.
It is composed of h, 2.5th, 3.5th, 4.5th (= 5th), and is a gear train set by setting the sub transmission unit 12 to a high gear (high) except for the first gear (1st). .. That is, in any of these gear trains, gear shifting as a whole of the automatic transmission 10 can be achieved by shifting only one of the sub-transmission unit 12 and the main transmission unit 13, and therefore the gear shift is performed according to either gear train. By doing so, simultaneous shifting is prevented. It is also possible to change the gear train to be adopted while traveling, and to change between the 2nd speed of the A gear train and the 2.5th speed of the B gear train,
The gear shift between the 3rd speed of the gear train and the 3.5th speed of the B gear train is
By switching the sub-transmission unit 12 to high or low without performing the gear shift of the main transmission unit 13, it is possible to achieve without simultaneous shifts. Shifts occur between the two.

Of the A gear train and the B gear train, the gear shift is normally performed according to the B gear train. An example of the shift map is shown in FIG. In FIG. 7, (I) is an upshift map and (II) is a downshift map. As is known from FIG. 7, if the throttle opening θ when starting is not particularly large,
It is designed to start at 1.5th speed, which is one speed higher than the lowest speed. That is, in the starting gear stage, the auxiliary transmission unit 12
Is set to the high speed stage (high).

Further, the automatic transmission 10 shown in FIG. 2 has an A gear when the first speed is set by the establishment of a predetermined condition or when the gear stage of the A gear train is set during traveling. Gear shifting is performed according to the train, and an example of the shift map of the A gear train is shown in FIG. Note that FIG. 8 shows only the upshift line. Moreover, in FIG.
Although the speed range is shown, the gear ratio of 1.5th speed is suitable for starting, the creep torque becomes small at 1.5th speed, and the gear ratio at 1.5th speed becomes low at low vehicle speed and low throttle opening. This is because the simultaneous shift between the second speed and the second speed is not a problem.

As the hydraulic circuit for controlling the brake Bo as described above, a solenoid valve is connected to the control port of the Bo control valve for controlling the supply and discharge of the hydraulic pressure to the brake Bo, and this solenoid valve is shown in FIG. A hydraulic circuit configured to be ON / OFF controlled by the electronic control unit 19 shown in can be adopted.

Next, the operation of the above-described shift control device will be described with reference to D
The control when shifting from the range to the N range will be mainly described with reference to FIGS. 9 and 10. 9 and 10 show one flow chart in a divided manner, and the reference numerals enclosed in circles indicate that lines with the same reference numerals are connected to each other.

In the flowcharts shown in these figures, first, in step 1, various signals such as vehicle speed V, throttle opening θ, and shift position are input, and then in step 2, whether or not the selected range is the D range. Make a decision. If the D range has been selected, the result of the determination in step 2 is "yes", so the flow proceeds to step 3 to read the shift pattern, and in step 4 shift is executed based on the vehicle speed V and the throttle opening θ. To do. Next, at step 5, it is determined whether or not the brake B0 of the subtransmission unit 12 is engaged at the currently set shift speed. No. 1.5 mentioned above
Speed, 2.5th speed, 3.5th speed, 5th speed (= 4.5th speed)
Since it is a shift stage that is set by setting the auxiliary transmission unit 12 to high (high speed stage), when these shift stages are set,
Since the result of the determination in step 5 is "yes", the process proceeds to step 6 where the flag F1 is set to "1" and then the process proceeds to step 7. Further, in the first speed, the second speed, the third speed, and the fourth speed, the sub-transmission unit 12 is set to low (low speed stage). Therefore, if any of these speed stages is set, step 5
Therefore, the flag F1 is set to "2" in step 8, and then the process proceeds to step 7. In addition,
If the determination result of step 2 is "NO", the process immediately proceeds to step 7.

In step 7, it is judged whether or not the N range is selected. If the judgment result is "yes",
In step 9, it is determined whether the vehicle speed V is lower than a predetermined reference vehicle speed V0. If the determination result of step 2 is "yes" and the determination result of step 7 is "yes", it means that the manual range from the D range to the N range has been performed. The reference vehicle speed V0 in step 9 is an extremely low vehicle speed close to a stop, and if the vehicle speed V in the N range is equal to or higher than this reference vehicle speed V0, the determination result in step 9 is "NO", and in that case, step 10 Then, it is judged whether the flag F1 is "1". If the flag F1 is "1", the brake B of the subtransmission unit 12
Since 0 is engaged and the sub-transmission unit 12 is in the high speed stage, if the determination result in step 10 is "yes", then in step 11, the engaged state of the brake B0 is continued. If the result of the determination in step 10 is "no", the process proceeds to step 12 and it is determined whether or not the flag F1 is set to "2". If the flag F1 is "2",
The brake B0 of the subtransmission unit 12 is released and the subtransmission unit 12 is released.
Is set to the low speed stage. Therefore, if the determination result of step 12 is "yes", step 13
And continue the release state of the brake B0. If the result of the determination in step 12 is "no", the control process returns.

On the other hand, if the vehicle speed V in the N range is substantially zero and the result of the determination in step 9 is "yes", the process proceeds to step 14 and the brake B of the auxiliary transmission section 12 is reached.
Engage 0. That is, both the 1.5th gear and the reverse gear, which are the starting gears, are set by setting the sub-transmission unit 12 to the high gear. Therefore, if the vehicle speed V is substantially zero in the N range, the starting gear or the reverse gear is set. In preparation for shifting, the auxiliary transmission unit 12 is set to the high speed stage in advance.

On the other hand, if the result of the determination in step 7 is "no", the process proceeds to step 15 to determine whether or not the selected range is the R range. If the result of the determination is "no", the control is performed. The process returns, and if "yes", the process proceeds to step 16 to execute the control for engaging the second clutch C2 and the fourth clutch C4. In that case, the brake B0 is already engaged because the vehicle speed V is shifted to the R range while the vehicle speed V is substantially zero, and the N range is shifted from the D range side. When the two clutches C2 and C4 are newly engaged, the reverse speed is set. Then, in step 17, the flag F1 is reset to zero and then the process returns.

Therefore, in the above control device, if the vehicle speed V when set to the N range is equal to or higher than the reference vehicle speed V0,
Since only the main transmission unit 13 is shifted to the neutral state without performing the shift in the sub transmission unit 12, the control for setting the neutral state becomes extremely easy and there is no risk of shift shock.

In the above control when the vehicle speed is high during the N range shift, the control in which the clutch in the main transmission unit 13 is disengaged to bring it into the neutral state is independently performed, and in the meantime, the shift in the auxiliary transmission unit 12 is performed. Since it is a control that is not performed, there is no particular problem in shifting the sub transmission unit 12 after waiting for the main transmission unit 13 to be in the neutral state. Therefore, for example, in step 13 described above.
10 may be replaced with control for engaging the brake B0 T1 seconds after shifting to the N range, as in step 13a shown in the margin of FIG. This delay time T1 second is the time until the clutch of the main transmission unit 13 is completely released, and may be changed according to the vehicle speed V and the oil temperature as shown in FIG. In addition, after shifting from the D range to the N range, the D range may be immediately re-shifted. Therefore, in such a quick shift, it may not be possible to secure the delay time T1 described above. Substantially maintains brake B0 in the released state, similar to step 13 above.

In the above embodiment, the automatic transmission provided with the gear train shown in FIG. 3 was explained, but the present invention can be applied to the automatic transmission provided with other gear trains. ..

[0030]

As is apparent from the above description, according to the shift control device of the present invention, even if the vehicle speed at the time of manual shift from the forward range to the neutral range is a high vehicle speed to some extent, the auxiliary transmission section is used for starting. Even if the shift stage is set to the high-speed stage, the main shift unit is placed in the neutral state by prohibiting the shift in the sub shift unit, so complicated control such as sequence control of the sub shift unit and the main shift unit with delicate timing is required. Control can be avoided, and as a result, shift control can be facilitated during manual shift to the neutral range, and shift shock can be prevented.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of the present invention.

FIG. 2 is a block diagram showing an embodiment of the present invention.

FIG. 3 is a skeleton diagram showing the gear train.

FIG. 4 is an operation table thereof.

FIG. 5 is an operation table for setting each shift speed of the A gear train.

FIG. 6 is an operation table for setting each shift speed of a B gear train.

FIG. 7 is a shift map for shifting according to a B gear train.

FIG. 8 is a shift map for shifting according to an A gear train.

FIG. 9 is a flowchart showing a part of a control routine.

FIG. 10 is a flowchart showing another part of the control routine.

FIG. 11 is a diagram showing a relationship between a delay time for engaging a brake of an auxiliary transmission unit, a vehicle speed, and an oil temperature.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 main transmission part 2 auxiliary transmission part 3 output shaft 4 range selection device 5 range detection means 6 vehicle speed detection means 7 transmission part control means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masahiro Hayabuchi, 10 Takane, Fujii-cho, Anjo City, Aichi Prefecture, Aisin A / D Aburyu Co., Ltd. (72) Masahiko Ando, 10 Takane, Fujii-cho, Anjo City, Aichi Prefecture・ In A-Daburi Co., Ltd.

Claims (1)

[Claims] 1. A neutral range in which a main transmission unit set to a plurality of forward gears and a reverse gear stage and a sub-transmission unit set to at least two high and low stages are connected in series and power is not transmitted to an output shaft. And a range selection device for selecting a plurality of ranges including a forward range for setting the forward stage by manual operation, the starting shift stage is set to the sub shift unit at a high speed stage and the main shift unit to a predetermined low speed stage. In a shift control device for an automatic transmission for a vehicle configured to be set, a range detection unit that detects a range selected by the range selection device, a vehicle speed detection unit that detects a vehicle speed, and a sub-transmission unit from a forward range. If the vehicle speed when switching to the neutral range is higher than the predetermined vehicle speed, maintain the shift speed in the forward range immediately before switching to the neutral range and move forward. Shift control apparatus for a vehicular automatic transmission, characterized in that if the Nji following vehicle the vehicle speed is predetermined when switched to a neutral range and a shifting portion control means for the high speed stage.