JP2616051B2 - 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 the automatic transmission can be multi-staged.

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 changeover between the main transmission and the subtransmission is normally performed by switching a friction element such as a hydraulically operated clutch or a brake. When the friction element is switched, a specific engagement shock is generated. .

For this reason, when the main transmission and the subtransmission are shifted synchronously, the freezing shock in each transmission occurs twice consecutively, and the frequency of occurrence of the shock increases or the engagement shock increases. Are simultaneously generated, the two shocks overlap.

In general, a shift determination of an automatic transmission is made based on a throttle opening and a vehicle speed ("NISSAN Full-Range Electronically Controlled Automatic Transmission Maintenance Manual", RE4R01A type; I-26, published in 1987)
When the vehicle speed is increased in a state where the accelerator pedal is depressed substantially constant during normal driving (throttle opening is a predetermined amount or more), an upshift is performed,
Upshifting is also performed when the throttle opening is reduced while the vehicle speed is substantially constant.

Therefore, at the time of the upshift when the latter throttle opening is decreased, the shift is performed with the operation of the driver releasing the foot from the accelerator pedal. The driver can make some predictions.

On the other hand, during the upshift with the throttle opening being substantially constant, the driver generally predicts the occurrence of a shift because the accelerator pedal is hardly operated. There is no.

Therefore, if the above-mentioned double change-shift is performed in a state where the driver does not predict the shift, the shock of the double change-change is caused by a normal shift (when only one of the main and sub-transmissions is shifted). Therefore, there is a problem that the driver particularly feels a large shift shock.

In view of the above, the present invention provides a shift control device for an automatic transmission that prohibits a double overshift in which a shift shock is particularly large in a driving state in which the driver does not expect a shift. The purpose is to do.

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 or more speed-change functions and a sub-transmission having at least two or more speed-change 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 such as a throttle opening and a vehicle speed. In an automatic transmission in which a suitable gear ratio is determined, the automatic transmission region in which the throttle opening is equal to or greater than a predetermined value and the vehicle speed is equal to or greater than a predetermined value is defined, and the current driving condition is within the automatic gear shifting region. Automatic shift area detecting means c for detecting the presence
Prohibiting means for prohibiting a double changeover in which the main and sub-transmissions a and b are synchronously upshifted and one is downshifted synchronously when the traveling condition is within the automatic shift range. In addition, as shown by a broken line in FIG. 1, a throttle opening change rate detecting means e for detecting a change rate of the throttle opening is provided, and the operation is prohibited when the change rate of the throttle opening is smaller than a predetermined value. The means d is actuated to inhibit double shifting.

Further, as another configuration of the present invention, as shown by a two-dot chain line in FIG. 1, there is provided a shift list map setting means f for recording a list of double shift shifts to be prohibited in advance, It is also possible to adopt a configuration in which the mode is searched from the double change gear list.

According to the shift control device for an automatic transmission of the present invention having the above-described configuration, when the current traveling condition is within an automatic shift range in which the driver does not anticipate the occurrence of a shift, the main shift is inhibited by the inhibiting means d. Since the double shift change of the transmission a and the auxiliary transmission b is prohibited, the double change shift with a large shock degree is prevented in a state where the driver does not expect it. This prevents the occurrence of a large shift shock.

Further, a throttle opening change rate detecting means e for detecting a change rate of the throttle opening is provided to prohibit when the change rate of the throttle opening is smaller than a predetermined value, that is, when the change in the accelerator pedal depression amount is small. By activating the means and prohibiting the double shift operation, it is possible to prevent the occurrence of a large shift shock with the driver's intention also in this case. Even in some cases, when the driver suddenly changes the depression of the accelerator pedal for which the shift can be predicted, it is possible to permit double changeover and perform effective acceleration and deceleration.

Further, a shift list map setting means f for recording a list of double change gears to be prohibited in advance is provided, and the current shift mode is searched from the double change gear list map. It is possible to prevent the occurrence of a malfunction in which the detection of the changeover is promptly processed.

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, the 1 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). Working fluid 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.

Also, the forward one-way clutch F / C ・ 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, the overrun clutch O / R / C is the first
Although not shown in the table, the overrun clutch OR
C is engaged at lower speeds of 3rd speed and lower with an accelerator opening of 1/16 or less, losing the function of the forward one-way clutch F / O · C, and allowing the engine brake to operate. ing.

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 is determined by the combination of the respective number of gears of the main transmission 12 having four forward speeds and the auxiliary transmission 14 having two-speed switching.
In the present embodiment, 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 controller 3 built in T control unit 28
ON and OFF are driven by control signals output from 0 (for controlling the first and second shift solenoids 22 and 24) and the sub-controller 32 (for controlling the third shift solenoid 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, and the friction elements are engaged and released, and the next As shown in Table 4, each shift speed can be obtained.

The ON / OFF signals output from the main controller 30 and the sub-controller 32 to the first, second, and third shift solenoids 22, 24, and 26 are determined by a shift determining unit. .

The shift determination means 34 receives a throttle opening signal detected by a throttle sensor 36 and a vehicle speed signal detected by a vehicle speed sensor 38, and is recorded in advance in a shift schedule setting means 40 based on the throttle opening and the vehicle speed. The current shift state is searched from the shifted shift schedule.

Here, in this embodiment, a double change prevention controller 42 is provided while the shift signal determined by the shift determination means 34 is output to the main controller 30 and the sub controller 32. Gearshift prevention controller
The shift signal processed in 42 is output to the main controller 30 and the sub-controller 32.

The double change gear shift prevention controller 42 is provided with an automatic gear change area detecting means 44 for detecting whether the current running condition is in the automatic gear change area, and a prohibition means 46 for prohibiting the double change gear is provided. Provided.

Here, the automatic shifting region is an operating region in which an upshift is performed in a state where the accelerator pedal is hardly operated during normal traveling (a state in which the throttle opening is substantially constant).
In other words, it is an operating region in which the driver does not predict the occurrence of a shift as general recognition, and this automatic shifting region is recorded in advance in the automatic shifting region map setting means 48,
The automatic speed change area map setting means 48 retrieves the information.

As shown in FIG. 4, the automatic transmission region sets a boundary line b connecting a low opening region of the throttle where a normally provided idle switch is turned on and a low vehicle speed region. On the other hand, it is a region where the throttle opening and the vehicle speed are each increased.

On the other hand, if the current shift determined by the shift determining means 34 is a double shift shift, the prohibiting means 46 inhibits the double shift shift under certain conditions, and And a function of stopping outputting the shift signal to the sub controller 32.

The double change gear to be prohibited by the prohibiting means 46 is a gear change in which the main transmission 12 and the sub transmission 14 are synchronously upshifted and one shifted down, as described above. As shown in Table 3 above, in the step-by-step shifting, the shifting from the second speed to the third speed, the shifting from the fourth speed to the fifth speed, and the shifting from the sixth speed to the seventh speed are performed. Corresponds to.

Note that the above-mentioned double shift change is not limited to such a case, and various types of double shift change list maps recorded in the shift list map setting means 50 are shown.

That is, the list map of the double change gear is shown in FIG. 5, in which a cross mark indicates a double change gear and a circle mark indicates a single change gear.

In addition, the double shift change prevention controller 42 includes the throttle opening sensor 36 and the vehicle speed sensor.
At the same time as the detection signals of 38, the throttle opening change rate signal calculated by the throttle opening change rate calculator 52 is input.

Further, a throttle opening degree change rate limit map setting means 54 in which a throttle opening degree change rate limit map is recorded is provided. The throttle opening change rate limit map is searched.

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 first step I in the above flowchart, the read throttle opening Th ₁ at the speed change decision means 34 reads the vehicle speed V in step II, searches the shift schedule from the traveling condition of the throttle opening Th ₁ and the vehicle speed V It is determined in step III whether or not to shift.

Then, if it is determined as "NO" in the step III are returned to the above step I, the routine proceeds to step IV in the case of "YES", reads the throttle opening Th ₂ again to the throttle opening change rate calculator 52 In the next step V, a throttle opening change rate ΔTh is calculated from the step opening.

still, As a result, the throttle opening change rate can be obtained.

Next, the double change gear shift prevention controller 42 searches the list map shown in FIG. 4 from the gear speeds of the main transmission 12 and the auxiliary transmission 14 determined by the gear speed determined in step III. It is determined in step VI whether or not the current gear shift is a double change gear (marked by X). If "YES", the process proceeds to step VII to open the throttle opening input to the double change gear prevention controller 42. Based on the degree and the vehicle speed, it is determined whether or not the current traveling condition is in the automatic shift region in the automatic shift region map of FIG.

If "YES" is determined in the step VII, the process returns to the step I without executing the double change gear, and if "NO", the step is performed.
Proceeding to VIII, the throttle opening change rate limit ΔTh ₀ corresponding to the current running conditions (throttle opening and vehicle speed) is searched from the map recorded in the throttle opening change rate limit map setting means 54, and In step IX, the throttle opening change rate limit ΔTh ₀ is compared with the throttle opening change rate ΔTh calculated in step V to determine whether or not ΔTh <ΔTh ₀ .

Then, if "YES" is determined in step IX, the process returns to step I without executing the shift, and if "NO" is determined, the process proceeds to step X,
The shift determined in the step III is executed, and thereafter, the process returns to the single step.

It should be noted that the case where "NO" is determined in the above step VI is a case of a single change-over shift, and the process directly proceeds to the above-mentioned step X, bypassing the above-mentioned step VII to step IX, and
Double shift is executed.

As described above, in the shift control device for an automatic transmission according to the present embodiment, the double shift-prevention controller 42 is provided so that the current traveling condition determined by the throttle opening and the vehicle speed is controlled by the driver. When the shift is within the automatic shift range in which the occurrence of the shift is not predicted, the double shift shift is prohibited. Therefore, the double shift shift having a large shock degree comes to the driver's surprise, and is particularly large. Since the shift shock is prevented from being felt, the ride comfort of the vehicle can be improved accordingly.

Further, a throttle opening change rate detecting means 52 for detecting a change rate of the throttle opening degree is provided, and when the change rate ΔTh of the throttle opening degree is smaller than a predetermined value ΔTh ₀ , a double shift change is prevented, and When the rate of change ΔTh is large, double changeover is allowed, so that
Even when the current running condition is in the automatic shift range, when the accelerator is decelerated rapidly, the amount of depression of the accelerator pedal is suddenly changed. In this case, the double shift is executed to effectively accelerate the vehicle. It can be carried out.

Further, in the present embodiment, a list map of the double shift is previously recorded by the shift list map setting means 50,
When the double shift is detected by the automatic shift area detecting means 44, simply searching the list map makes it easy to perform the double shift.
Since it is possible to detect whether the shift is a double change or a single change, it is possible to promptly detect such a type of shift, thereby simplifying the structure of the control device. At the same time, occurrence of malfunction can be prevented.

In this embodiment, if there is a shift mode in which the shift is allowable even in the double shift shift, the column of the allowable double shift shift is removed from the list map, or
By placing a circle, the shift can be executed at any time even in the case of a double shift.

By the way, in this embodiment, even in the case where the double shift is prohibited, the single shift is allowed at any time as the minimum shift. Is set small, it is possible to minimize the shock felt by the driver.

Further, in the present embodiment, if the current traveling condition is outside the above-mentioned automatic speed change range, a double shift change is allowed. In this case, when the driver operates with the accelerator pedal conscious, Predicts the occurrence of a shift to some extent, so that even if the double changeover is executed, it is not felt as a very large shock, and the ride comfort is not significantly reduced.

In this embodiment, taking an example in the case of an upshift, 2
Although the description has been given of the prevention of the double shift, the present invention is not limited to this. If the double shift is performed even in the case of a downshift, the automatic shift range and the throttle opening change may be changed similarly to the above embodiment. Needless to say, the double shift can be prevented by using the rate or the like.

Further, in this embodiment, the main transmission 12 is provided with four forward gears and the auxiliary transmission 14 is switched between two gears. However, the present invention is not limited to this. Machine 14
The present invention can be applied to any device having two or more shift speeds.

Effects of the Invention As described above, in the shift control device for an automatic transmission according to the present invention, in claim 1, an automatic shift region in which the driver does not predict occurrence of a shift is defined, When the vehicle is within the automatic transmission range, the double shift operation of the automatic transmission having the main and auxiliary transmissions is prohibited.
Since the double shift with a large shock degree is prevented in a state that the driver does not expect, a large shift shock that is unexpectedly generated by the driver is prevented.

Further, the rate of change of the throttle opening is obtained, and when the rate of change of the throttle opening is smaller than a predetermined value, the double shift change is prohibited. When the accelerator pedal can be predicted and the sudden change occurs, a double shift can be allowed, and effective acceleration and deceleration can be performed.

Further, according to a second aspect of the present invention, a double change gear list map to be prohibited in advance in the first or second aspect is provided, and the current gear change mode is searched from the double change gear list map. Accordingly, various excellent effects can be achieved in that the detection of the double shift can be quickly processed with a simple structure, and the occurrence of a malfunction can be prevented.

[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 an explanatory view showing an embodiment of an automatic shift area used in the present invention. FIG. 5 is an explanatory view showing an embodiment of a list of double shifts used in the present invention. FIG. 5 is a flowchart showing one processing example of a program executed in the present invention. 10 ... automatic transmission, 12 ... main transmission, 14 ... auxiliary transmission,
28: A / T control unit, 34: Shift determining means, 36: Throttle sensor, 38: Vehicle speed sensor, 40:
... Shift schedule setting means, 42... Double shift change prevention controller, 4.
... prohibiting means, 48 ... automatic shift area setting means, 50 ... shift list map setting means, 52 ... throttle opening change rate calculator, 54 ... throttle opening change rate limit map setting means.

Claims (2)

(57) [Claims] 1. A main transmission having at least two or more gears and a sub-transmission having at least two or more gears are arranged in series, and based on running conditions such as throttle opening and vehicle speed. In an automatic transmission in which at least one of the main transmission and the sub transmission is shifted so that the final transmission ratio is determined by the product of the respective transmission ratios, the throttle opening is not less than a predetermined value. And an automatic speed change region in which the vehicle speed is equal to or higher than a predetermined value, an automatic speed change region detecting means for detecting that the current traveling condition is within the automatic speed change region is provided, and the traveling condition is within the automatic speed change region. In addition, the main and auxiliary transmissions are synchronously upshifted on one side,
Prohibiting means for prohibiting a double changeover for downshifting the other is provided, while throttle opening change rate detecting means for detecting a change rate of the throttle opening is provided, and the detection value of the detecting means is smaller than a predetermined value. In addition, a shift control device for an automatic transmission, characterized in that the double shift operation is prohibited by operating the prohibiting means. A shift list map setting means for recording a list of double shift gears to be prohibited in advance;
2. The shift control device for an automatic transmission according to claim 1, wherein the current shift mode is searched from the double shift change list map.