JP2830182B2 - Transmission control device for automatic transmission - Google Patents

Description

The present invention relates to an automatic transmission mounted on a vehicle, and more particularly to an automatic transmission mounted on a vehicle.
The present invention relates to a shift control device for an automatic transmission configured by arranging a main transmission and a subtransmission each having a plurality of gears in series.

2. Description of the Related Art A conventional automatic transmission for a vehicle includes a main transmission (first transmission) and an auxiliary transmission (second transmission) arranged in series as disclosed in Japanese Patent Application Laid-Open No. 62-83541. In some cases, the final transmission ratio is determined by the product of the transmission ratios of both transmissions.

Therefore, in such an automatic transmission, the number of gears obtained by multiplying the number of gears of the main transmission by the number of gears of the sub-transmission is obtained.
For example, the main transmission has three forward speeds and the subtransmission has two speeds (Lo, Hi
In the case of (switching), as shown in Table 1 below, a total of six forward gears can be obtained, and a multi-speed automatic transmission can be achieved.

SUMMARY OF THE INVENTION However, such a conventional shift control device for an automatic transmission, when the overall shift speed is shifted from the second speed to the third speed and from the fourth speed to the fifth speed, Upshifting of the transmission and downshifting of the auxiliary transmission are performed in synchronization.

That is, the gear change between the main transmission and the sub-transmission is normally performed by switching a friction element such as a brake by a hydraulically operated clutch. When the friction element is switched, a specific engagement shock is generated. You.

For this reason, in the conventional automatic transmission, when the main transmission and the auxiliary transmission are shifted synchronously, their engagement shocks may overlap with each other. Riding comfort is significantly deteriorated.

That is, FIG. 6 shows the acceleration characteristics when the conventional automatic transmission performs the double changeover, and the maximum of the vibration F generated when the main transmission starts the shift (start point P). When the sub-transmission starts shifting in the portion A, the minimum portion B of the torque fluctuation that is first generated when the sub-transmission starts shifting (start point Q), and the local maximum in the main transmission. Part A
Is generated in the same phase as the minimum portion C of the vibration generated next. Therefore, the reversal after the two are superimposed is generated as the peak torque D, which causes the shift shock to be significantly increased. There were challenges.

In view of such a conventional problem, the present invention provides a small time difference between the shift start timings of the main transmission and the sub transmission,
A vibration that appears immediately after the start of shifting of the transmission performed earlier,
A shift control device for an automatic transmission in which the torque shock accompanying the start of shifting of a transmission performed later is set to the opposite phase to suppress a vibration generated thereafter, thereby reducing an engagement shock. The purpose is to provide.

Means for Solving the Problems In order to achieve the above object, as shown in FIG. 1, the present invention provides a main transmission a having at least two-stage shift functions and a sub-transmission having at least two-stage shift functions. A transmission b is arranged in series, and at least one of the main and sub transmissions a and b is shifted based on running conditions,
In the automatic transmission in which the final transmission ratio is determined by the product of the respective transmission ratios, the main transmission a and the auxiliary transmission b are synchronized and one is upshifted and the other is based on the running conditions. Is downshifted 2
Double shift detection means c for detecting double shifts c
A shift start means d for shifting either the main transmission a or the auxiliary transmission b in advance by detecting a double shift shift; and a main shift being shifted in advance by the shift start means d. A vibration cycle detecting means e for detecting a cycle of a minimum and a maximum of the vibration appearing immediately after the shift of the transmission a or the auxiliary transmission b; A shift delay means 4 for determining the other shift start timing of the main transmission a or the auxiliary transmission b which has been shifted ahead.
And is provided.

According to the shift control device for an automatic transmission of the present invention having the above-described configuration, when a double shift shift is performed, one of the main transmission a and the auxiliary transmission b is shifted ahead of time,
Since the shift start timing of the other transmission is determined based on the vibration cycle that appears immediately after the shift start of the preceding transmission, the start timing of the transmission that is shifted later is set to the transmission timing that is shifted earlier. Of the main and sub-transmissions a and b can be set so that the phase of the vibration that appears immediately after the start of the shift and the phase of the torque fluctuation accompanying the start of the shift of the transmission to be shifted later are opposite. The generation of vibrations when is polymerized can be greatly reduced.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

That is, FIG. 2 shows an embodiment of a shift control device for an automatic transmission according to the present invention. The automatic transmission 10 shown in FIG. ,
It is constituted by arranging in series a subtransmission 14 in which two-stage switching at a constant speed is performed.

The main gear train of the transmission 12 and the sub transmission 14 is configured as shown in FIG. 3, the main transmission 12 includes a first planetary gear set PG ₁ and the second planetary gear set PG _2, and the auxiliary transmission machine 14 includes a third planetary gear set PG _3.

The first, second, and third planetary gear sets PG ₁ , PG ₂ , PG ₃ are each configured as a simple planetary gear, and the first, second, and third sun gears are provided.
S ₁ , S ₂ , S ₃ , first, second, third pinion gears P ₁ , P ₂ , P ₃ ,
The first and second ring gears R ₁ , R ₂ and R ₃ and the first, second and third pinion carriers PC ₁ , PC ₂ and PC ₃ are provided.

In the main transmission 12, the first and second planetary gear sets PG ₁ , PG ₁
The gear train composed of _2, connects the input shaft I / S as illustrated reverse clutch R / C to connect the first sun gear S _1, the input shaft I / S and the first pinion carrier PC ₁ the high clutch H / C, the forward clutch F / C which connects the first pinion carrier PC ₁ and the second ring gear R _2, the band brake B / B to the first sun gear S ₁ is fixed to the casing C / S side, a first Pinion carrier P
The low and reverse brake L & R / B is provided for fixing the C ₁ to the casing C / S side.

Further, the forward clutch F / C and the second ring gear R
₂ , a forward one-way clutch F / OC is provided, and a first pinion carrier PC ₁ and a casing C
/ S is provided between the first pinion carrier PC ₁ and the second ring gear R.
₂ , an overrun clutch O / R / C is arranged in parallel with the forward one-way clutch F / O / C.

In addition, the gear train composed of the auxiliary transmission 14 in the third planetary gear set PG _3, direct clutch D / C which connects the third pinion carrier PC ₃ as shown and the third sun gear S _3, the 3 sun gear S ₃ is the reduction brake R · D / B for fixing the casing C / S is provided.

Furthermore, reduction one-way clutch R · D / O · C between the third sun gear S ₃ and casing C / S is arranged.

The second pinion carrier PC _{2 serving as} an output member of the main transmission 12 and the third ring gear R _{3 serving as} an input member of the auxiliary transmission 14 are connected via an intermediate shaft M / S. I have.

In FIG. 3, the torque of the engine E is input to the input shaft I / S via a torque converter T / C.

Incidentally, in the main transmission 12, as shown in Table 2 below, each friction element (R / C, H / C, F / C, B / B, L & R / B) is supplied from a control valve (not shown). Shifting hydraulic pressure (line pressure)
By engaging and disengaging the gears, various speeds can be obtained.

In the table, a circle indicates a fastened state, and a blank indicates a released state.

In addition, the forward one-way clutch F / O ・ C
The second ring gear R to the first pinion carrier PC _1
2 is free when rotating in the forward direction, locked when rotating in the reverse direction, and the low one-way clutch L / O
C is unlocked, upon rotation in the reverse direction during rotation of the first forward direction of the pinion carrier PC _1.

By the way, although the overrun clutch O / R / C is not shown in Table 1, the overrun clutch OR
As the R / C is engaged at the low speed side of the third speed or lower with an accelerator opening of 1/16 or less, the function of the forward one-way clutch F / OC is eliminated, and the engine brake is operated. It has become.

On the other hand, in the subtransmission 14, the input rotation is output at a constant speed (Hi) state by engaging the direct clutch D / C, and the deceleration (Lo) state is output by releasing the direct clutch D / C. It is output.

In addition, the above reduction one-way clutch R / D / O
· C is adapted to be locked at the time of free and will, reverse at the time of the forward rotation of the third sun gear S _3.

In the automatic transmission 10, the final speed ratio output from the output shaft O / S is determined by the product of the speed ratio of the main transmission 12 and the speed ratio of the auxiliary transmission 14. The number of gears obtained by the transmission 10 depends on the main transmission 12
In this embodiment, the main transmission 12 is switched to four forward speeds, and the auxiliary transmission 14 is switched to two speeds (Lo, Hi).
As a result, as shown in Table 3 below, a total of eight forward gears can be shifted.

The control valve has a first transmission for switching the main transmission 12.
A shift solenoid 22 and a second shift solenoid 24;
A third shift solenoid 26 for switching the sub-transmission 14 is provided, and the first, second, and third shift solenoids 22, 24, 26
Main transmission control 30 built in T control unit 28 (for controlling first and second shift solenoids 22 and 24)
And auxiliary transmission control 32 (third shift solenoid
ON / OFF drive is performed by a control signal output from the control circuit 26).

Therefore, the first, second, and third shift solenoids 22, 24, 26
Are turned ON and OFF, the first, second, and third shift valves (not shown) built in the control valve are switched, so that the friction elements are engaged and released, and the next fourth Each shift stage is obtained as shown in the table.

By the way, the ON / OFF command output from the main transmission controller 30 and the auxiliary transmission controller 32 to the first, second, and third shift solenoids 22, 24, and 26 is controlled by a shift control as shift start means. The data is output from the controller 34.

The shift control controller 34 includes a throttle sensor
Throttle opening signal detected by 36 and vehicle speed sensor 38
The shift speed is determined based on a preset shift schedule based on the throttle opening and the vehicle speed.

Here, the present embodiment employs an acceleration sensor on the automatic transmission 10.
A vibration cycle detecting means 42 for inputting a detection signal of the acceleration sensor 40 to the A / T control unit 28 and detecting the maximum and minimum cycles of acceleration vibration output from the automatic transmission 10; A shift delay unit 44 is provided for determining a time difference between the start of the shift of the main transmission 12 and the start of the shift of the auxiliary transmission 14 based on the calculation result of the vibration cycle detection unit 42.

The vibration cycle detecting means 42 is constituted by a maximum and minimum measurement circuit 46 and a cycle calculation circuit 48, and the maximum and minimum measurement circuit
In 46, the minimum time and the maximum time of the natural period existing in the acceleration vibration are measured from the acceleration signal detected by the acceleration sensor 40, and the period calculation circuit 48 calculates the time between the minimum and the maximum from these minimum and maximum times. Is calculated.

On the other hand, the shift delay means 44 is constituted by a main / sub transmission time difference determination circuit 50 and a delay controller 52 interposed between the shift control controller 34 and the sub transmission controller 32. In the auxiliary transmission time difference determination circuit 50, the vibration cycle Δ calculated by the cycle calculation circuit 48 is used.
The time difference ΔT at which the main transmission 12 and the subtransmission 14 start shifting is determined from T ′, and the delay controller 52 outputs a shift signal output from the transmission control controller 34 to the subtransmission controller 32 by the time ΔT. Delay.

The function of the shift control device for an automatic transmission according to the present embodiment having the above configuration will be described below with reference to the flowchart of FIG.

That is, the above-described flowchart is performed for a predetermined short time (for example, 10
msec). First, the throttle opening is read in step I, and the vehicle speed V is read in step II. In step III, a shift schedule is searched from the running conditions of the throttle opening and the vehicle speed to determine whether a shift is performed. If “NO”, the process returns to step I, and if “YES”, the process proceeds to step IV.

In step IV, it is determined whether the main transmission 12 and the auxiliary transmission 14 are in a double shift mode in which one is upshifted and the other is downshifted in synchronization with each other.
If "NO" is determined in step VI, the process proceeds to step V to execute a normal shift, and if "YES" is determined, step VI
Then, the shift of the main transmission 12 is executed first.

The shifts executed in steps V and VI are performed by outputting shift command signals from the shift control controller 34 in FIG. 2 to the main transmission controller 30 and the auxiliary transmission controller 32. When shifting in V, the delay controller 32 is not operated,
The command signal output from the shift control controller 34 is immediately output to the sub-transmission controller 32, while
To shift in VI, the delay controller 32 is activated,
A command signal input to the sub-transmission controller 32 is delayed.

Then, the process proceeds from step VI to step VII, where the acceleration vibration g detected by the acceleration sensor 40 (see FIG. 5)
In the next step VIII, it is determined whether or not the acceleration vibration g is at a minimum (X portion in FIG. 5).
If "O", return to step VII again, "YES"
In the case of, the process proceeds to step IX, and the current time at the minimum is set to T ₁ (5th
(See the figure).

In the next step X, the acceleration vibration g is read again. In step XI, it is determined whether or not this is the maximum (Y portion in FIG. 5). If “NO”, the process returns to step X again, and “YES” is returned. In this case, the process proceeds to step XII, and the current time at the maximum is set to T ₂ (see FIG. 5).

Note that the processing from step VII to step XII is performed by the local maximum and minimum measuring circuit 46 in FIG. 2, and the processing of the next step XIII and step XIV is performed by the cycle calculating circuit 48.

That is, in the next step XIII, the period ΔT ′ (see FIG. 5) between the minimum and the maximum of the vibration is calculated from the above T ₁ and T ₂ by ΔT ′ = T ₂ −
Calculated from T _1, it is determined based on the time difference [Delta] T of the shift start with the next step XIV in the main transmission 12 and the sub transmission 14 to the period [Delta] T '.

That is, the time difference ΔT is the reverse of the phase of the vibration generated by the main transmission 12 that has been shifted earlier (starting point P) and the output torque fluctuation generated by the sub-transmission 14 that is shifted later. In this embodiment, as shown in the vibrating force characteristics of the sub-transmission shown in FIG. 5, when the sub-transmission 14 starts shifting, the fluctuation is first minimized (part B). , The shift start time point Q of the subtransmission 14 is set to a minimum value (part E) of the vibration generated in the main transmission 12.

Therefore, the time difference ΔT is equal to the period ΔT ′ and the coefficient 4.
5 (.DELTA.T = 4.5.DELTA.T '), which is output from the main / sub transmission time difference determination circuit 50 to the delay controller 52, and the time difference ΔT is counted by the delay controller 52. The shift command signal output from the shift control controller 34 to the auxiliary transmission controller 32 is delayed.

Therefore, in step XV, it is determined whether or not the ΔT time has elapsed after the start of shifting of the main transmission 12. If “NO”, the process returns to step XV again.If “YES”, the process proceeds to step XVI. By stopping the operation of the delay controller 52, a shift command signal is output to the auxiliary transmission controller 32, and the shift of the auxiliary transmission 14 is started.

As described above, in the shift control device of the present embodiment,
When a repetitive shift is detected, first the shift of the main transmission 12 is advanced, and then the shift of the sub-transmission 14 is started after the time difference ΔT calculated by the main and sub-transmission time difference determination circuit 50. Therefore, the phase of the acceleration vibration of the preceding main transmission 12 and the phase of the output torque fluctuation of the sub-transmission 14 that is shifted later can be reversed, and the vibration generated thereafter (fifth In the portion (H in the figure), a particularly prominent vibration peak can be eliminated to make a gentle fluctuation.

Therefore, the acceleration felt by the vehicle body is reduced, so that the shift shock due to the double return shift can be significantly reduced.

Note that the double change gear is not limited to the case where the main transmission 12 is upshifted and the case where the auxiliary transmission 14 is downshifted. This may be the case when the transmission 12 is downshifted and the subtransmission 14 is upshifted.

Further, in the present embodiment, the main transmission
Although the case where the transmission 12 is shifted ahead is disclosed, the auxiliary transmission 14
May be shifted in advance, and the main transmission 12 may be shifted afterward. In this case, the same function as in the present embodiment can be achieved by setting the phases of the vibrations generated by the two to be opposite. Obtainable.

Further, in the present embodiment, the case where the acceleration sensor 40 is used to detect the vibration of the transmission which is shifted ahead in advance and the minimum and the maximum are measured from the vibration caused by the acceleration fluctuation is disclosed. Instead of using the acceleration sensor, a torque sensor may be used instead, and the minimum and maximum of the vibration may be measured from the torque fluctuation output from the automatic transmission 10.

Furthermore, in the present embodiment, the main transmission 12 is provided with four forward gears and the auxiliary transmission 4 is switched between two gears. However, the present invention is not limited to this. The present invention can be applied to the transmission 14 as long as the transmission 14 has two or more shift speeds, and the double shift shift is executed.

Effect of the Invention As described above, in the shift control device for an automatic transmission according to the present invention, a main transmission having at least two-stage shift functions and a sub-transmission having at least two-stage shift functions are provided. Are automatic transmissions arranged in series, and the main transmission and the auxiliary transmission are synchronized, and one of them is upshifted.
When a double changeover in which the other is downshifted is performed, one of the main transmission and the subtransmission is shifted in advance, and the start timing of the transmission to be shifted later is set to the preceding shift. Because the determination is made based on the vibration cycle that appears immediately after the transmission starts, the phase of the vibration generated by the transmission that is shifted earlier and the torque fluctuation of the transmission that is shifted later are always in opposite phases. And it is possible to significantly reduce the vibrations generated thereafter, thereby providing an excellent effect that the shift shock at the time of the double shift can be significantly reduced.

[Brief description of the drawings]

1 is a schematic diagram showing the concept of the present invention, FIG. 2 is a schematic diagram showing an embodiment of the present invention, and FIG. 3 is a schematic diagram showing a gear train of an automatic transmission to which the present invention is applied. FIG. 4 is a flow chart showing an example of processing of a program executed in the present invention. FIG. 5 is a vibration characteristic diagram generated at the time of a double shift change performed in the present invention. FIG. 6 is a conventional shift control. FIG. 7 is a diagram illustrating vibration characteristics generated at the time of a double shift change performed by the device. 10 ... automatic transmission, 12 ... main transmission, 14 ... auxiliary transmission,
28: A / T control unit, 34: Shift control controller (shift start means), 36: Throttle sensor,
38: vehicle speed sensor, 42: vibration cycle detecting means, 44: shift delay means.

Continuation of the front page (56) References JP-A-62-83451 (JP, A) JP-A-64-15560 (JP, A) JP-A-62-4950 (JP, A) JP-A-2-146369 (JP) JP-A-63-30639 (JP, A) JP-A-63-34352 (JP, A) (58) Fields studied (Int. Cl. ⁶ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (1)

(57) [Claims] 1. A main transmission having at least two-stage shifting functions and a sub-transmission having at least two-stage shifting functions are arranged in series.
An automatic transmission in which at least one of the sub-transmissions is shifted so that the final transmission ratio is determined by the product of the respective transmission ratios. A double change gear shift detecting means for detecting a double change gear shift in which one is upshifted and the other is downshifted in synchronism with the main transmission or the auxiliary transmission. A shift start means for shifting one of the gears first, and a cycle of a minimum and a maximum of the vibration appearing immediately after the shift of the main transmission or the sub-transmission which is shifted earlier by the shift start means is detected. A vibration surrounding detecting means; a shift delaying means for determining a shift start timing of the other of the main transmission or the sub-transmission which has been shifted ahead based on the minimum and maximum cycles detected by the vibration cycle detecting means; To A shift control device for an automatic transmission, wherein the shift control device is provided.