JP2008169880A - Automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To execute a shift right after manual restoration from a manual shift mode to an automatic shift mode with good responsiveness, and to execute a shift right after automatic restoration from the manual shift mode to the automatic shift mode without feeling shock. <P>SOLUTION: When a shift right after a changeover from the manual shift mode to the automatic shift mode is generated, a hydraulic control means 26 controls hydraulic pressure right after the changeover depending on whether the changeover of the shift mode is one by a manual operation of a second operation means 34 (manual restoration) or one by operation of an automatic shift mode restoration means with passage of a predetermined time (automatic restoration). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an automatic transmission, and more particularly to an automatic transmission capable of switching from an automatic transmission mode to a manual transmission mode and vice versa.

  An automatic transmission of a vehicle such as an automobile (hereinafter simply referred to as a vehicle) has an “automatic shift mode” that automatically selects an optimum shift speed corresponding to the engine load and the vehicle speed, so that the operation burden on the driver is reduced. It is a convenient device that can greatly reduce the noise, and is installed in many vehicles today regardless of the vehicle type.

  By the way, although the automatic transmission has an excellent merit of reducing the burden on the driver as described above, the emblem feeling (sensory sensation) intended by the driver when going down a steep slope in the automatic transmission mode, for example. Engine brakes) may not be obtained. In such a case, in a general vehicle with an automatic transmission, the shift lever is operated to switch from the drive position (D) to a specific shift range (for example, the 2nd speed range or 1st speed range in some cases). The desired emblem feeling can be obtained by performing operations such as D → 2 and D → 2 → 1.

  Further, in recent years, a vehicle with an automatic transmission capable of switching from the automatic transmission mode to the manual transmission mode and vice versa, that is, shifting the shift lever from the drive position (D) to the manual transmission position (M). Many vehicles with automatic transmissions that can be switched have been found. For example, in the technique described in Patent Document 1 (hereinafter referred to as the first conventional technique), when the shift lever switched to the manual shift position (M) is operated downward from the neutral position, the shift to the next lower shift stage is performed. An operation (downshift) is performed, or when operated upward, a gearshift operation (upshift) to the upper gear is performed, and the shift lever is neutral each time the operation is performed. It comes to return to the position.

  In such a vehicle, when going down a steep slope as described above, the shift lever is switched from the drive position (D) to the manual shift position (M), and the shift lever is lowered appropriately until a desired emblem is obtained. You just have to do the operation. Further, in such a vehicle, it is possible to perform a driving operation like a vehicle with a manual transmission by raising or lowering the shift lever while switching the shift lever to the manual shift position (M). You can also enjoy sporty driving on roads and circuits.

  However, in the first conventional technique, when the automatic shift mode is canceled and a desired shift stage is selected, (1) the shift lever is switched from the drive position (D) to the manual shift position (M). It is necessary to follow the procedure of operating the shift lever up or down to select a desired gear position. In addition, in order to return to the automatic shift mode, (3) the shift lever is moved to the manual shift position (M). To return to the drive position (D).

  Therefore, in the first prior art, since there are many operation procedures, for example, when the engine brake is suddenly required, the operation may not be in time. Or, since it is necessary to intentionally return to the automatic transmission mode, the shift lever is often forgotten to return and the vehicle continues to run in the manual transmission mode.

As a technique for improving the drawbacks of the first conventional technique (hereinafter referred to as a second conventional technique), for example, a technique described in Patent Document 2 is known.
In the second prior art, in addition to the shift lever in the first prior art, “operating means” for shifting down and up to a position where the fingertip can be operated while holding the steering handle. It has.

  This operation means is called, for example, a shift-down switch and a shift-up switch or a shift-down paddle lever and a shift-up paddle lever. The shift-down switch and the shift-down paddle lever are used for a shift-down, a shift-up switch and a shift-up switch, for example. The paddle lever is for shifting up. Hereinafter, for convenience of explanation, representatives of the “operation means” are a shift down paddle lever and a shift up paddle lever.

  In the second prior art, not only the manual shift speed selection function by the shift lever in the first prior art but also the shift down paddle lever even when the shift lever is at the drive position (D). By simply operating the shift up paddle lever, it is possible to immediately switch to the manual shift mode and shift down or up to the desired shift stage. This solves the disadvantages (many operating procedures). Further, when the shift lever is at the drive position (D), after a predetermined time has elapsed after operating the downshift paddle lever or the upshift paddle lever, the automatic shift mode is automatically restored. Thus, the second drawback of the first prior art (forgetting to return to the automatic transmission mode) is also solved.

JP-A-2004-270833 (switching to manual shift mode with a shift lever) Japanese Patent Laid-Open No. 11-257485 (the shift lever can be switched to the manual shift mode by the operating means provided near the handle even when the shift lever is in the automatic shift mode position, and further returns to the automatic shift mode after a predetermined time. )

  As described above, the second conventional technique is superior in that it can solve the drawbacks of the first conventional technique, but there are problems to be improved in the following points.

  In the second prior art, the return from the manual shift mode to the automatic shift mode is based on the intentional operation of the driver (that is, the M → D operation of the shift lever), the shift down paddle lever or the shift up paddle lever. Some occur automatically after a lapse of a predetermined time after operation. The former is called “manual return”, and the latter is called “automatic return”.

  In many cases, gear shifting often occurs immediately after manual return. The reason can be explained as follows. That is, the manual shift mode selection by the shift lever is usually performed by downshift intended for engine braking. In this case, when the driver no longer needs engine braking, the shift lever is moved from M to D. Manual return will be performed. For this reason, the gear change control device determines the optimum gear position based on a predetermined gear shift diagram immediately after manual return. In this case, of course, on the gear shift diagram, the gear shift on the high speed gear side is naturally performed. Since the gear becomes the optimum gear, an upshift occurs with high probability immediately after manual return.

  Considering the shift hydraulic pressure and engine torque reduction in this case, if the shift control for the automatic shift mode is executed just because the shift is in the automatic shift mode, the shift is relatively slow despite the shift immediately after manual return. Since it progresses, the driver feels uncomfortable (the shift is not felt even though the shift lever is operated from M to D).

  Therefore, with regard to the shift associated with the manual return, priority is given to responsiveness, that is, it is conceivable to execute shift control for manual shift, for example, in order to complete the shift in a short time with better responsiveness than for automatic shift. . In this case, some shift shocks are generated, but such shift shocks are also preferable for actively notifying the driver that a shift due to manual return has occurred.

  However, simply doing so in turn causes inconveniences during automatic recovery. In other words, in automatic recovery, the driver returns to the automatic transmission mode at a timing that does not involve the driver at all. However, if a large shift shock occurs at such timing, the driver feels uncomfortable (the gear shifts even though nothing has been done). Woke up).

  As described above, in the second prior art, there are still insufficient measures for performing the shift immediately after “manual return” with good responsiveness and performing the shift immediately after “automatic return” without experiencing a shock. There are issues to be improved in this regard.

  Accordingly, an object of the present invention is to perform a shift immediately after a manual return from the manual shift mode to the automatic shift mode with high responsiveness, and without experiencing a shock immediately after the automatic return from the manual shift mode to the automatic shift mode. It is to provide an automatic transmission that can be performed.

The invention according to claim 1 is an automatic transmission that shifts and outputs torque from a drive source, and is based on a predetermined automatic shift pattern according to a vehicle speed and an engine load, and a target gear stage or a target gear ratio. First control means for executing an automatic shift mode for determining the first shift speed, second control means for executing a manual shift mode for determining a target shift speed or target gear ratio by manual operation of the first operation means, and the automatic shift mode And a manual operation mode, a second operation means for selecting the manual transmission mode by a manual operation, a hydraulic control means for controlling the oil pressure at the time of the shift according to the selected transmission mode, and the second operation means in the automatic transmission mode. If the first operating means is manually operated during the selection, a switching means for switching the selected shift mode from the automatic shift mode to the manual shift mode, Automatic shift mode return means for releasing the manual shift mode and returning to the automatic shift mode when a predetermined condition is satisfied during manual shift mode selection, and the hydraulic control means includes the manual shift mode When a shift occurs immediately after switching from the mode to the automatic shift mode, whether the shift mode is switched by a manual operation of the second operating means or a switch by operating the automatic shift mode return means Accordingly, the automatic transmission is characterized in that the hydraulic pressure immediately after the switching is controlled.
According to a second aspect of the present invention, the oil pressure control means causes the speed change by the operation of the automatic speed change mode return means rather than the oil pressure used when the speed change is generated by manual operation of the second operation means. 2. The automatic transmission according to claim 1, wherein control is performed such that a hydraulic pressure that is used when a hydraulic pressure occurs is lower.
According to a third aspect of the present invention, the hydraulic pressure used when the shift is generated by manual operation of the second operating means is a hydraulic pressure used during the manual shift mode selection, and the automatic shift 3. The automatic transmission according to claim 2, wherein the hydraulic pressure used when the shift is generated by the operation of the mode return means is the hydraulic pressure used during the selection of the automatic shift mode.
According to a fourth aspect of the present invention, there is provided a torque reduction means for reducing the torque of the drive source during a gear shift, and the torque reduction means is provided when a shift occurs immediately after switching from the manual shift mode to the automatic shift mode. The torque amount to be reduced is changed depending on whether the mode is switched by manual operation of the second operating means or switching by operating the automatic shift mode return means. Item 4. The automatic transmission according to any one of Items 1 to 3.
According to a fifth aspect of the present invention, the torque reducing means reduces torque when the automatic shift mode return means is activated rather than when the shift is generated by manual operation of the second operating means. 5. The automatic transmission according to claim 4, wherein the amount is increased.
According to a sixth aspect of the present invention, the torque reduction means is in a state where the manual shift mode is selected as a reduction amount of the torque when the shift immediately after the mode change is performed by the manual operation of the second operation means. 6. The automatic transmission according to claim 5, wherein a reduction amount is used, and a reduction amount during selection of the automatic transmission mode is used as a reduction amount of the torque when the return means is operated.
The invention according to claim 7 is an automatic transmission that shifts and outputs torque from a drive source, and is based on a planned automatic shift pattern according to a vehicle speed and an engine load. First control means for executing an automatic shift mode for determining the first shift speed, second control means for executing a manual shift mode for determining a target shift speed or target gear ratio by manual operation of the first operation means, and the automatic shift mode And a manual operation mode, a second operation means for selecting the manual transmission mode by a manual operation, a hydraulic control means for controlling the oil pressure at the time of the shift according to the selected transmission mode, and the second operation means in the automatic transmission mode. If the first operating means is manually operated during the selection, a switching means for switching the selected shift mode from the automatic shift mode to the manual shift mode, An automatic transmission mode return means for releasing the manual transmission mode and returning to the automatic transmission mode when a predetermined condition is satisfied while the manual transmission mode is selected, and a torque reduction for reducing the torque of the drive source during the transmission And the torque reduction means, when a shift occurs immediately after switching from the manual shift mode to the automatic shift mode, whether the mode is switched by manual operation of the second operating means, The automatic transmission is characterized in that the amount of torque to be reduced is changed according to whether the automatic shift mode return means is switched or not.

  In the present invention, the shift immediately after the manual return from the manual shift mode to the automatic shift mode is performed with good responsiveness, and the shift immediately after the automatic return from the manual shift mode to the automatic shift mode is performed without experiencing a shock. An automatic transmission that can be provided can be provided.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is an overall configuration diagram of an embodiment, and more particularly, shows a power train configuration of a vehicle including an automatic transmission equipped with a torque converter together with a control system thereof. The power train is used as a drive source. Engine 10, an automatic transmission 11, and a torque converter 12 that drives and couples between them. The automatic transmission 11 is a stepped automatic transmission that includes a plurality of friction elements and a planetary gear, and that achieves a desired shift stage by selectively fastening and releasing the plurality of friction elements.

  The engine 10 includes a throttle valve 14 whose opening degree is controlled according to the amount of depression of the accelerator pedal 13, and the air amount according to the opening degree of the throttle valve 14 (hereinafter referred to as the throttle opening degree) and the engine speed. It inhales through the air cleaner 15. The engine 10 includes a group of injectors (hereinafter referred to as an injector group 16) and an ignition device 17 provided for each cylinder, and these are controlled by an engine controller 18. The engine controller 18 receives a signal Q from the intake air amount sensor 19 that detects the engine intake air amount Q and a signal I from the idle switch 20 that is turned on when the accelerator pedal 13 is released.

  Based on these input information, the engine controller 18 injects a predetermined amount of fuel from the injector group 16 into a predetermined cylinder according to the operating state of the engine 10. Further, when the accelerator pedal is released when the driver removes his / her foot from the accelerator pedal 13, fuel cut is performed to stop the fuel supply in order to prevent waste of fuel consumption during coasting.

  The engine controller 18 ignites ignition plugs of a predetermined cylinder at a predetermined timing via the ignition device 17 in accordance with the operating state of the engine based on the input information. As a result, the engine 10 is operated as specified, and the fuel is cut as specified during coasting. Further, the engine controller 18 prevents engine stall by performing fuel cut recovery for re-injecting a predetermined amount of fuel from the injector group 16 to a predetermined cylinder when the engine rotation falls below a predetermined value.

  Rotational torque (also referred to as engine torque) generated in the engine 10 is transmitted to the automatic transmission 11 via the torque converter 12. The automatic transmission 11 selectively engages and releases a friction element in the control valve 21 to determine a selected shift speed based on a traveling condition and controls a plurality of clutch pressure regulating valves 22 and 23 in the control valve 21. Thus, the selected shift speed is achieved, and the rotational torque from the engine 10 transmitted to the automatic transmission 11 via the torque converter 12 is shifted at a gear ratio corresponding to the selected shift speed, and this shift power is reduced. Output from the output shaft 25 to a drive wheel (not shown).

  The clutch pressure regulating valves 22 and 23 are provided by the number of friction elements, and are controlled by the transmission controller 26. The transmission controller 26 includes a signal I from the idle switch 20, a signal from a throttle opening sensor 27 that detects the opening of the throttle valve 14 (throttle opening TVO), and the rotational speed of the transmission output shaft 25. Is input as a signal from the vehicle speed sensor 28 that detects the vehicle speed VSP, and a signal from the turbine rotation sensor 29 that detects the output rotation speed Nt of the torque converter 12 (also referred to as the turbine rotation speed). A signal (described later) from the select lever unit 30 and a signal (described later) from the steering handle unit 31 are also input.

  The select lever unit 30 generally includes a guide panel 33 having a substantially H-shaped guide groove 32 attached to a center box, a floor tunnel, or a dashboard provided between a driver seat and a passenger seat, and the guide groove. And a select lever 34 erected from the vehicle body floor or dashboard so as to be movable along the vehicle body 32.

In the guide groove 32, characters “P”, “R”, “N”, “D” and “L” are engraved in order from the top of the left vertical side of the H character. The characters “+”, “M”, and “−” are stamped at the upper end and the middle of the right vertical side, respectively. These characters have the following meanings:
"P": P range position where the automatic transmission 11 is set to the parking (P) range.
“R”: an R range position in which the automatic transmission 11 is set to the reverse travel (R) range.
“N”: N range position where the automatic transmission 11 is set to the neutral (N) range.
“D”: D range position where the automatic transmission 11 is set to the forward automatic shift (D) range.
“L”: an L range position in which the automatic transmission 11 is set to a predetermined low shift (for example, second speed or first speed) (L) range.
“M”: an M range position where the automatic transmission 11 is set to a manual shift (M) range.
• “+”: Manual upshift (M +) position during manual shifting.
"-": Manual downshift (M-) position during manual shifting.

  In this way, the P range position, the R range position, the N range position, the D range position, and the L range position are arranged in a straight line, the D range position, the side and the M range position are arranged, and the M range position is The manual upshift (M +) and manual downshift (M-) positions are arranged in both directions parallel to the arrangement direction of the P range position, R range position, N range position, D range position, and L range position. The select lever 34 can be operated at these positions.

  However, after the select lever 34 is operated to the manual upshift (M +) position or the manual downshift (M−) position and then the operating force is released, the select lever 34 is self-returned to the M range position.

The select lever unit 30 is further provided with a plurality of range switches listed below for detecting the operation position of the select lever 34.
Inhibitor switch 35: When the select lever 34 is in the P range position, the P range signal Sp is output. When the select lever 34 is in the R range position, the R range signal Sr is output, and the select lever 34 is in the N range position. N range signal Sn is output, D range signal Sd is output when select lever 34 is in the D range position, and L range signal Sl is output when select lever 34 is in the L range position.
M range switch 35M: Outputs an M range signal Sm when the select lever 34 is in the M range position.
Select lever upshift switch 35u: Outputs a select lever upshift signal Sm + when the select lever 34 is in the manual upshift (M +) position.
Select lever downshift switch 35d: Outputs a select lever downshift signal Sm- when the select lever 34 is in the manual downshift (M-) position.

  Next, the steering handle unit 31 is provided with a switch element for downshifting and upshifting corresponding to the “operating means” of the prior art at an appropriate position where the steering wheel unit 31 can be operated by a finger while holding the hand. ing. The switch element is not particularly limited to this. For example, a shift-up switch provided at two positions on the left and right of the surface of the steering wheel 36 and a shift-down switch provided at two positions on the left and right of the rear surface of the steering wheel 36 are used. Alternatively, a pair of left and right lever switches (also referred to as paddle levers) attached to the outer periphery of a center column (not shown) that rotatably supports the shaft 36a of the steering wheel 36 may be used. This lever switch may be of a type that rotates together with the steering wheel 36 or may be of a fixed type. In the case of a lever switch, either one of the lever switches may be used exclusively for downshifting, and the other may be used exclusively for upshifting, or it may be used for upshifting when pulled forward and downshifting when pushed backward. It may be.

  Hereinafter, for convenience of explanation, the “operation means” in this embodiment is provided at the left and right two positions on the rear surface of the steering wheel 36 and the steering shift up switches 37 and 37 provided at the two right and left positions on the surface of the steering wheel 36. Steering shift down switches 38, 38, and the steering shift up switches 37, 37 output a steering up shift signal Pad + every time they are operated with a fingertip. , 38 output a steering downshift signal Pad− every time it is operated with a fingertip.

  Each signal from the select lever unit 30 (P range signal Sp, R range signal Sr, N range signal Sn, D range signal Sd, L range signal S1, M range signal Sm, select lever upshift signal Sm +, select lever downshift The signal Sm−) is input to the transmission controller 26, and similarly, each signal (steering upshift signal Pad +, steering downshift signal Pad−) from the steering handle unit 31 is also input to the transmission controller 26.

  The transmission controller 26 determines the selected shift speed based on the input information, and controls the plurality of clutch pressure regulating valves 22 and 23 in the control valve 21 to achieve the selected shift speed. As a result, the rotational torque from the engine 10 transmitted to the automatic transmission 11 via the torque converter 12 is shifted at a gear ratio corresponding to the selected shift speed, and this shift power is driven from the output shaft 25 to a drive (not shown). Output to wheels.

  That is, when the select lever 34 is in the P range position, the automatic transmission 11 receives the P range signal Sp from the inhibitor switch 35 and all the friction elements corresponding to the P range are opened. When the select lever 34 is in the R range position, the automatic transmission 11 receives the R range signal Sr from the inhibitor switch 35, and the automatic transmission 11 sets the corresponding friction element so that the reverse gear position corresponds to the R range. Conclude. When the select lever 34 is in the N range position, the automatic transmission 11 receives the N range signal Sn from the inhibitor switch 35 and all the friction elements corresponding to the N range are opened. When the select lever 34 is in the D range position, the automatic transmission 11 receives the D range signal Sd from the inhibitor switch 35, and the automatic transmission 11 is in a gear change mode (automatic transmission mode) corresponding to the D range. Shift control is executed. Further, when the select lever 34 is in the M range position, the automatic transmission 11 receives the M range signal Sm from the M range switch 35M, and the automatic transmission 11 performs the shift control so as to be in the shift mode (manual shift mode) corresponding to the M range. Execute. That is, when the select lever 34 is operated to the manual upshift (M +) position, the automatic transmission 11 receives the select lever upshift signal Sm + from the select lever upshift switch 35u, and the automatic transmission 11 is up to the current gear position. When the shift is executed and the select lever 34 is operated to the manual downshift (M−) position, the automatic transmission 11 receives the select lever downshift signal Sm− from the select lever downshift switch 35d and Downshift is executed for the shift speeds.

  Furthermore, even if the select lever 34 is in the D range position, for example, when the steering shift up switches 37, 37 of the steering handle unit 31 are operated, the steering up shift signals from the steering shift up switches 37, 37 are operated. Upon receiving Pad +, the automatic transmission 11 temporarily switches to the manual shift mode and performs an upshift with respect to the current shift stage. Similarly, the select lever 34 is, for example, in the D range position. When the steering shift down switches 38, 38 of the steering handle unit 31 are operated, the automatic transmission 11 temporarily enters the manual shift mode in response to the steering down shift signal Pad- from the steering shift down switches 38, 38. Cut To run down shift against Ete current gear.

  If the above shift control is arranged, it can be divided into “automatic shift control” and “manual shift control”. The automatic transmission mode falls under the category of “automatic transmission control”, and the manual transmission mode becomes “manual transmission control”.

  In “automatic shift control”, the transmission controller 26 performs shift control of the automatic transmission 11 as described below by well-known calculations based on the various input information described above. First, on the basis of a planned shift diagram from the vehicle speed VSP and the throttle opening TVO, an optimum shift stage for the current vehicle operating state is selected, and a plurality of clutch pressure regulating valves are used to shift to the optimum shift stage. 22 and 23 are controlled. The control hydraulic pressure for each friction element during gear shifting and the torque reduction amount of the engine during gear shifting used in this “automatic gear shifting control” is referred to as “automatic gear shifting control hydraulic pressure” or “automatic gear shifting torque reduction”. To do. These “automatic shift control hydraulic pressure” and “automatic shift torque reduction” are appropriately set with emphasis on mitigation of shift shock rather than shift response. In other words, even if the achievement of the desired shift speed is somewhat delayed, it is set as an appropriate hydraulic characteristic or torque down characteristic that causes less shift shock and does not make the driver feel uncomfortable.

  On the other hand, the “manual shift control” is executed in two cases in the present embodiment. The first case is when the select lever 34 is moved from the D range position to the M range position, and the second case is the steering shift up switches 37 and 37 of the steering wheel 36 or the steering shift down at the D range position. This is when the switches 38 and 38 are operated.

  In these two cases of manual shift control, the transmission controller 26 operates based on the driver's operation of the select lever 34 to the M + position or M− position or the operation of the steering shift up switch 37 and the steering shift down switch 38. Shift control of the automatic transmission 11 is performed by controlling the clutch pressure regulating valves 22 and 23 so that the shift to the desired gear stage intended by the user is performed. That is, when the M range position is changed to the M + position or the M− position, or when the steering shift up switches 37 and 37 and the steering shift down switches 38 and 38 of the steering wheel 36 are operated, the current shift stage is set to one stage. An upshift is performed to switch to a higher position, or a downshift is performed to switch the current gear position to a lower position.

  The control hydraulic pressure for each friction element during the shift and the torque reduction amount of the engine during the shift used in the “manual shift control” are referred to as “manual shift control hydraulic pressure” or “manual shift torque down”. To do. These “manual gear shift control oil pressure” and “manual gear shift torque down” are appropriately set with an emphasis on gear shift response, contrary to the aforementioned “automatic gear shift control hydraulic pressure” and “automatic gear shift torque down”. Set. The reason is that the manual shift is an intentional operation by the driver, and for example, it is necessary to immediately switch to the desired shift stage without delay as in an engine brake immediately before a sharp curve. When shifting response is emphasized, a slight shift shock occurs, but such a shift shock (unless it is an excessive shift shock) is a clue to notify the driver that the shift operation has been performed. It can be said that it is rather preferable.

Next, switching between “automatic shift control” and “manual shift control” in the present embodiment will be described.
FIG. 2 is a diagram showing a program for switching between automatic shift control and manual shift control. The automatic transmission control may be referred to as an automatic transmission mode, and the manual transmission control may be referred to as a manual transmission mode. This program is repeatedly executed every predetermined short time. When the program is started, first, the position of the shift lever 34 is determined (step S1). If the position is the M position, the manual shift mode is selected (step S6), the required manual shift control is executed, and the current process is terminated.

  On the other hand, if it is determined in step S1 that other than the M position, that is, the P, R, N, D, or L position, the steering switch (the steering shift up switches 37, 37 or the steering shift down switches 38, 38) It is determined whether or not has been operated (step S2). If it is determined that the steering switch has been operated, the manual shift mode is selected (step S6), the required manual shift control is executed, and the current process is terminated.

  On the other hand, if the operation of the steering switch is not determined in step S2, it is next determined whether or not the manual shift mode has been selected by the operation of the steering switch within the predetermined time Tα (step S2). S3). If the determination result is “NO”, that is, if the manual shift mode has not been selected by operating the steering switch within the predetermined time Tα in the past, the automatic shift mode is selected (step S5). Then, after executing the required automatic shift control, the current process is terminated. If the determination result in step S3 is “YES”, that is, in the past, the manual shift mode by operating the steering switch within the predetermined time Tα is set. If the selection has been made, it is next determined whether or not the predetermined time Tα has elapsed (step S4), and until the predetermined time Tα elapses, the manual shift mode is selected (step S6) and the required manual operation is performed. When the shift control is executed and the elapse of the predetermined time Tα is determined, the automatic shift mode is selected (step S5), the required manual shift control is executed, and the current process is terminated. To do.

  Thus, according to the program shown in FIG. 2, the manual shift mode can be selected when the shift lever 34 is in the M position, and the shift lever 34 is in the P, R, N, D, or L position. Sometimes, even when the steering switch (steering shift up switch 37, 37 or steering shift down switch 38, 38) is operated, it is manual regardless of the position of the shift lever 34 (P, R, N, D or L position). A shift mode can be selected.

  Further, the return from the manual shift mode to the automatic shift mode can be performed manually by manually returning the shift lever 34 from the M position to the D position, and the steering switch (the steering shift up switch 37, 37 or the steering shift down switch 38, 38) can be “automatically restored” after a predetermined time Tα has elapsed.

  The purpose of this embodiment is to perform a shift executed under the automatic shift mode immediately after the manual return from the manual shift mode to the automatic shift mode with good responsiveness, and from the manual shift mode to the automatic shift mode. The shift performed in the automatic shift mode immediately after the automatic return is to be performed without experiencing a shock.

  Characteristic items of the present embodiment for achieving this object are: control hydraulic pressure data and torque down data used at the time of “manual return”, control hydraulic pressure data and torque down data used at the time of “automatic return”, Is in the point where each is optimized. That is, the control hydraulic pressure data and torque down data used in the “manual return” can be performed with high responsiveness for the shift executed in the automatic shift mode immediately after the manual return from the manual shift mode to the automatic shift mode. For the shift executed under the automatic shift mode immediately after the automatic return from the manual shift mode to the automatic shift mode, the control hydraulic pressure data and torque down data used at the time of “automatic return” are optimized. It is in the point optimized so that it can be performed without experiencing a shock. Hereinafter, the control oil pressure data is simply referred to as “control oil pressure”, and the torque down data is simply referred to as “torque down”.

  FIG. 3 is a diagram showing a control program including characteristic items of the present embodiment. In this figure, first, switching from the M mode (manual shift mode) to the D mode (automatic shift mode), that is, the occurrence of the "automatic return" or "manual return" is determined (step S11). If no return occurs, the program ends. If a return occurs, the return type (automatic return / manual return) is determined (step S12). In any return type, it is determined whether or not a shift occurs from the current vehicle speed and throttle opening with reference to the shift diagram (steps S13 and S15). If a shift occurs, the shift control is executed using the control hydraulic pressure and torque reduction optimized for each return type even in the automatic shift mode (steps S14 and S16). Exit the program.

  Here, step S14 is a shift control in the case of manual return, and step S16 is a shift control in the case of automatic return. As described above, in the case of manual return, the shift immediately after the return must be performed with good responsiveness, and in the case of automatic return, the shift immediately after the return must be performed without experiencing a shock. Therefore, in step S14, the shift immediately after the manual return can be performed with good responsiveness by using the “hydraulic pressure / torque data referred to in the M mode (manual shift mode)” even in the automatic shift mode. In step S16, since the shift is in the automatic shift mode, the shift immediately after the automatic return can be performed without experiencing a shock by using “hydraulic pressure / torque data to be referred to in the D mode (automatic shift mode)”. Like that.

4 and 5 are diagrams showing respective control hydraulic pressures and torque-down characteristics used in automatic return and manual return.
First, with reference to FIG. 4, the control hydraulic pressure and torque down characteristics used in automatic return will be described. The hydraulic pressure data and the torque down amount are data at the time of shifting performed in the automatic shift mode. First, when a shift determination is made at time t0 based on the shift diagram, piston stroke control of the target friction element is performed. In the piston stroke control, precharge pressure control for giving a high pressure oil pressure command for promoting the piston stroke and subsequent low pressure standby pressure control are performed. Torque phase control is executed to increase the hydraulic pressure command at a predetermined gradient for each input torque from the time t1 when the required time has elapsed, and when the gear phase change occurs and the inertia phase starts (time t2), each input torque The inertia phase control is executed at a predetermined gradient (smaller than the torque phase control gradient), and the torque of the engine 10 is reduced by a predetermined amount at the start of the inertia phase (time t2), and the gear ratio becomes a predetermined value. At this point, the torque reduction is finished, and then the gradient of the hydraulic pressure command is increased again when the target gear ratio is reached (time t3). After a predetermined time has elapsed (time t4), the hydraulic pressure command is set to the maximum. Raise to high pressure.

  Such control oil pressure and torque down characteristics are familiar as characteristics for general automatic transmissions. In short, a smooth shift can be performed without causing the vehicle occupant to experience a shift shock as much as possible. It can be said that the characteristics are optimized.

  Next, with reference to FIG. 5, the control hydraulic pressure and torque down characteristics used in manual return will be described. Note that the hydraulic pressure data and the torque reduction amount in this case are data used at the time of a shift performed in the manual shift mode, although the shift is performed in the automatic shift mode. In this figure, a characteristic line indicated by a broken line is the characteristic line of FIG. 4 for comparison. First, when a shift determination is made at time t0 based on the shift diagram, piston stroke control of the target friction element is performed in the same manner as hydraulic data at the time of shifting in the automatic shift mode. A torque phase is executed in which the hydraulic pressure command is increased at a predetermined gradient for each input torque from the time t1 when the required time has elapsed. . At this time, the gradient in the torque phase control in the manual shift mode is set to be larger than that in the automatic shift mode. When a gear ratio change occurs and the inertia phase starts (time t2 ′), the inertia phase control is executed with a predetermined gradient for each input torque. The gradient in the inertia phase control in the manual shift mode is set to be larger than that in the automatic shift mode. Further, the torque of the engine 10 is reduced by a predetermined amount as the inertia phase starts (time t2 ′). This predetermined amount is set to be larger than that in the automatic transmission mode. Then, when the gear ratio reaches a predetermined value, the torque reduction is finished, and then the gradient of the hydraulic pressure command is increased again at the time when the gear ratio of the target gear stage is reached (time t3 ′), After elapse (time t4 ′), the hydraulic pressure command is increased to the maximum pressure. Comparing these two types of characteristic lines (the characteristic line for automatic return and the characteristic line for manual return), the characteristics of control oil pressure and torque down that are higher and faster in manual return are recognized. That is, the manual return fastening hydraulic pressure (control hydraulic pressure) is steeper than the automatic return control hydraulic pressure indicated by the broken line, and reaches the target value earlier. For this reason, the manual return gear ratio changes earlier than the automatic return gear ratio indicated by the broken line, and as a result, speed change control that is faster than the automatic return is realized. Similarly, the torque reduction of the engine 10 also changes faster and more greatly than that of the automatic return indicated by the broken line, and as a result, the change in the longitudinal acceleration G of the vehicle converges earlier.

  As described above, in the present embodiment, the control hydraulic pressure and torque down used at the time of manual return and the control hydraulic pressure and torque down used at the time of automatic return are optimized so that the responsiveness in the case of manual return and automatic Since the shift shock mitigation is achieved at the time of return, the shift immediately after the manual return from the manual shift mode to the automatic shift mode is performed with good responsiveness, and the automatic return from the manual shift mode to the automatic shift mode is performed. It is possible to provide an automatic transmission that can perform a gear shift immediately after that without experiencing a shock.

  Therefore, when a shift occurs immediately after the shift mode is switched at the time of “automatic return”, it is possible to prevent the occurrence of a shift shock with respect to the shift at a point not intended by the driver by using a low hydraulic pressure. When a shift occurs immediately after switching to the shift mode at the time of “manual return”, high pressure hydraulic pressure is used to improve the response of the shift to the shift expected by the driver and give the driver a sense of incongruity The advantage is that there is nothing.

  In addition, the hydraulic pressure data used for the shift at the time of manual return is the hydraulic pressure used during the manual shift mode selection, and the hydraulic pressure data used at the time of the shift at the automatic return is selected during the automatic shift mode. Therefore, it is not necessary to have dedicated hydraulic data for each return time, and the data capacity does not increase.

  Similarly, the torque down data used at the time of shifting at the time of manual return is torque down data used during manual shifting mode selection, and the torque down data used at the time of shifting at the time of automatic return is Since the torque down data is used during the automatic transmission mode selection, it is not necessary to have dedicated torque down data for each return, and the data capacity does not increase in this respect as well.

  In the embodiment described above, both “control hydraulic pressure” and “torque down” of manual return and automatic return are optimized, but this is the best mode. Either “control hydraulic pressure” or “torque down” may be optimized.

  FIG. 6 is a diagram showing a control program in which “control oil pressure” for manual return and automatic return is optimized. In this figure, the same steps as those in FIG. 3 are given the same reference numerals. The difference is step S14a and step S16a. That is, step S14a is the shift control in the case of manual return, and step S16a is the shift control in the case of automatic return, but step S14a becomes “hydraulic data” that is referred to in the M mode (manual shift mode). Thus, the difference is that the torque down data is removed, and that step S16a is "" hydraulic pressure data "to be referred to in the D mode (automatic shift mode)" and the torque down data is removed. Any hydraulic data should be optimized so that the shift immediately after manual return can be performed with good responsiveness, or optimized so that the shift immediately after automatic return can be performed without experiencing a shock. That's fine.

  FIG. 7 is a diagram showing a control program in which “torque down” of manual return and automatic return is optimized. Also in this figure, the same steps as those in FIG. 3 are given the same reference numerals. The difference is step S14b and step S16b. That is, step S14b is the shift control in the case of manual return, and step S16b is the shift control in the case of automatic return, but step S14b is “torque down data” to be referred to in the M mode (manual shift mode). Thus, the difference is that the hydraulic pressure data is removed, and that step S16b is “torque down data to be referred to in the D mode (automatic shift mode)” and the hydraulic pressure data is removed. All the torque down data are optimized so that the shift immediately after the manual return can be performed with good responsiveness, and optimized so that the shift immediately after the automatic return can be performed without experiencing a shock. I just need it.

1 is an overall configuration diagram of an embodiment. It is a figure which shows the switching program of automatic transmission control and manual transmission control. It is a figure which shows the control program containing the characteristic matter of this embodiment. It is a figure which shows the control hydraulic pressure and torque down characteristic which are used in the case of automatic return. It is a figure which shows the control oil_pressure | hydraulic and torque down characteristic used in the case of a manual return. It is a figure which shows the control program which optimized "control oil pressure" of manual return and automatic return. It is a figure which shows the control program which optimized "torque down" of manual return and automatic return.

Explanation of symbols

10 Engine (drive source)
11 automatic transmission 26 transmission controller (first control means, second control means, hydraulic control means, switching means, automatic transmission mode return means, torque reduction means)
34 Shift lever (second operating means)
37 Steering shift up switch (first operation means)
38 Steering shift down switch (first operating means)

Claims (7)

An automatic transmission that shifts and outputs torque from a drive source,
First control means for executing an automatic shift mode for determining a target shift speed or a target gear ratio based on a planned automatic shift pattern according to a vehicle speed and an engine load;
Second control means for executing a manual shift mode for determining a target gear position or target gear ratio by manual operation of the first operating means;
Second operating means for selecting the automatic shift mode and the manual shift mode by manual operation;
Hydraulic control means for controlling the hydraulic pressure at the time of shifting according to the selected shifting mode;
Switching means for switching the selected transmission mode from the automatic transmission mode to the manual transmission mode when the first operation unit is manually operated while the second operation unit is selecting the automatic transmission mode;
Automatic shift mode return means for releasing the manual shift mode and returning to the automatic shift mode when a predetermined condition is satisfied during the manual shift mode selection by the operation of the switching means,
When the shift occurs immediately after switching from the manual shift mode to the automatic shift mode, the hydraulic pressure control means may switch the shift mode by a manual operation of the second operating means or return to the automatic shift mode. An automatic transmission characterized in that the hydraulic pressure immediately after the switching is controlled depending on whether the switching is caused by the operation of the means.   The hydraulic pressure control means is a hydraulic pressure used when the shift is generated by the operation of the automatic shift mode return means, rather than a hydraulic pressure used when the shift is generated by a manual operation of the second operating means. 2. The automatic transmission according to claim 1, wherein control is performed so that the hydraulic pressure is lower.   The hydraulic pressure used when the shift is generated by manual operation of the second operating means is the hydraulic pressure used during the manual shift mode selection, and the shift is performed by the operation of the automatic shift mode return means. 3. The automatic transmission according to claim 2, wherein the hydraulic pressure used when the automatic transmission is generated is a hydraulic pressure used during the selection of the automatic transmission mode. A torque reduction means for reducing the torque of the drive source during a shift;
The torque reduction means is configured to switch the mode when the shift occurs immediately after switching from the manual shift mode to the automatic shift mode, whether the mode is switched by manual operation of the second operation means, or the automatic shift mode return means. 4. The automatic transmission according to claim 1, wherein the amount of torque to be reduced is changed in accordance with whether the torque is switched due to operation.   The torque reducing means increases the amount of torque to be reduced when the automatic shift mode return means is operated, compared to when the shift is generated by manual operation of the second operating means. The automatic transmission according to claim 4. The torque reducing means includes
Regarding the shift immediately after the mode change, the reduction amount during the manual shift mode selection is used as the torque reduction amount when the second operation means is switched manually, and the return means is activated when the return means is activated. 6. The automatic transmission according to claim 5, wherein a reduction amount during selection of the automatic transmission mode is used as the torque reduction amount. An automatic transmission that shifts and outputs torque from a drive source,
First control means for executing an automatic shift mode for determining a target shift speed or a target gear ratio based on a planned automatic shift pattern according to a vehicle speed and an engine load;
Second control means for executing a manual shift mode for determining a target gear position or target gear ratio by manual operation of the first operating means;
Second operating means for selecting the automatic shift mode and the manual shift mode by manual operation;
Hydraulic control means for controlling the hydraulic pressure at the time of shifting according to the selected shifting mode;
Switching means for switching the selected transmission mode from the automatic transmission mode to the manual transmission mode when the first operation unit is manually operated while the second operation unit is selecting the automatic transmission mode;
Automatic shift mode return means for releasing the manual shift mode and returning to the automatic shift mode when a predetermined condition is satisfied during the manual shift mode selection by the operation of the switching means;
Torque reduction means for reducing the torque of the drive source at the time of shifting,
The torque reduction means is configured to switch the mode when the shift occurs immediately after switching from the manual shift mode to the automatic shift mode, whether the mode is switched by manual operation of the second operation means, or the automatic shift mode return means. An automatic transmission characterized in that the amount of torque to be reduced is changed according to whether the torque is switched due to operation.

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