JP2016138631A - Control device for automatic transmission and shift method for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for automatic transmission and a shift method for automatic transmission in which a frequent gear shift under a kick-down operation intended by a driver during automatic shift is restricted and both fuel consumption and drivability are improved.PROCEDURE FOR SOLVING THE PROBLEM: A control device 20 of an automatic transmission 14 is constituted in such a way that a dead zone R having a preset vehicle speed range Δd in a direction of a vehicle speed axis Lb is arranged from a high opening vehicle speed Vu2 that is a vehicle speed of full open [100%] of an accelerator opening degree Ao at an up-shift line Lu set at a shift map M1 toward a low vehicle speed side and when a kick-down switch 24 becomes ON in the dead zone R, a control for prohibiting a down-shift at a shift stage is carried out, and in turn when the kick-down switch 24 is turned ON at a lower vehicle speed than the range of the dead zone R, the down-shift of the shift stage is executed.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a control device for an automatic transmission and a shift method for an automatic transmission, and more particularly, to an automatic transmission that improves fuel efficiency and drivability by suppressing frequent shifts caused by a kick-down operation during automatic shift. The present invention relates to a control device and a shift method of an automatic transmission.

  One of the shifting operations of the automatic transmission is a kick-down operation that lowers the gear stage by one step, that is, downshifts the gear stage when the driver depresses the accelerator pedal to accelerate.

  In this regard, a kickdown switch that detects further depression of the accelerator pedal beyond the full opening of the accelerator opening is provided, and when the driver intends to kick down, that is, there was further depression of the accelerator pedal. In some cases, a device capable of downshifting with the stepping operation as a kickdown operation has been proposed (see, for example, Patent Document 1).

  This device makes it possible to perform the kickdown operation intended by the driver by using a kickdown switch. On the other hand, the kickdown operation is performed in a situation where the vehicle speed and the accelerator opening are near the upshift line. Then, since a so-called shift busy state occurs in which the upshift is performed immediately after the downshift, there is a problem that fuel consumption and drivability deteriorate.

JP 2013-87782 A

  The present invention has been made in view of the above-described problems, and the problem is that an automatic transmission control device and an automatic transmission that improve fuel efficiency and drivability by suppressing frequent shifts due to kick-down operations during automatic shifts. It is to provide a speed change method for a transmission.

  The control device for an automatic transmission according to the present invention for solving the above-described problem has a shift map in which an upshift line and a downshift line based on the vehicle speed and the accelerator pedal opening of the accelerator pedal are set for each shift stage. An accelerator pedal configured to perform upshifting and downshifting of the shift stage of the automatic transmission using the shift map during automatic shifting, and to be depressed even when the accelerator opening exceeds fully open When the kick-down switch is turned on when a kick-down operation is applied to the accelerator pedal and the accelerator pedal is depressed beyond the fully open position, the gear speed is lowered. In a control device for an automatic transmission that performs control to execute a shift, when the accelerator opening is fully opened in the upshift line A dead zone with a preset vehicle speed range in the vehicle speed axis direction is provided on the low vehicle speed side from the high opening vehicle speed, which is a high speed, and when the kick down switch is turned on in the dead zone, the gear position is lowered. Control for prohibiting shift is performed, and when the kick-down switch is turned on at a vehicle speed lower than the range of the dead zone, control for performing downshift of the shift stage is performed. is there.

In addition, the automatic transmission shift method of the present invention for solving the above-described problems is based on the downshift line and the upshift line set in the shift map based on the vehicle speed and the accelerator opening amount during automatic shift. In the shift method of the automatic transmission that upshifts and downshifts the shift stage of the transmission, when the vehicle speed decelerates beyond the downshift line, the shift stage is downshifted based on the downshift line, In other cases, the kick-down operation that is stepped on the accelerator pedal beyond the full opening of the accelerator opening is a vehicle speed from the high opening vehicle speed that is the vehicle speed when the accelerator opening is fully opened in the upshift line to the low vehicle speed. The shift stage is downshifted only when it occurs at a lower vehicle speed than the range of the dead zone provided on the side.

  According to the automatic transmission control device and the automatic transmission speed change method of the present invention, the kickdown operation occurs in the dead zone provided on the low vehicle speed side from the high opening vehicle speed of the upshift line set in the shift map. In this case, since the shift stage is not downshifted, it is possible to avoid an upshift immediately after the downshift. As a result, frequent shifting due to the kickdown operation intended by the driver during automatic shifting can be suppressed, and fuel consumption and drivability can be improved.

It is explanatory drawing which illustrates embodiment of the control apparatus of the automatic transmission of this invention. It is explanatory drawing of the shift map of FIG.

  The automatic transmission control device and the automatic transmission shifting method of the present invention will be described below. FIG. 1 illustrates the configuration of an embodiment of a control device 20 for an automatic transmission 14 according to the present invention. The control device 20 performs control to execute upshift and downshift of the shift stage of the automatic transmission based on the shift map M1 and the kickdown switch 24 during automatic shift.

  As shown in FIG. 1, in the vehicle 10 including the automatic transmission 14, the power of the engine 11 is transmitted to the fluid coupling (fluid coupling) 12, and the clutch (friction engagement element) 13 is transmitted from the fluid coupling 12. Is transmitted to the automatic transmission 14. Then, it is transmitted from the automatic transmission 14 to a differential gear (differential gear) 16 via a propulsion shaft (propeller shaft) 15, and is transmitted from the differential gear 16 to a drive wheel 18 via a drive shaft (drive shaft) 17. ing. The automatic transmission 14 will be described using AMT as an example, but is not limited to AMT, and may be, for example, a torque converter type AT.

  The automatic transmission 14 has a plurality of shift stages (including a reverse shift stage) with different gear ratios, and when the manual shift mode is selected by a shift lever (not shown), the shift lever by the driver Based on these operations, the control device 20 performs upshift and downshift of the gear stage. Further, the automatic transmission 14 has a vehicle speed V detected by the vehicle speed sensor 21 and an accelerator opening Ao of the accelerator pedal 23 detected by the accelerator opening sensor 22 when the automatic shift mode is selected by the shift lever. Based on the above, the control device 20 performs upshift and downshift of the gear stage.

  The control device 20 performs shift control of the shift stage of the automatic transmission 14 and connection / disconnection control of the clutch 13, and is connected in communication with an engine control device that controls the engine 11 (not shown). The control device 20 has a shift map M1 used when the automatic transmission mode is selected by the shift lever. In the shift map M1, an upshift line Lu and a downshift line Ld based on the vehicle speed V and the accelerator opening Ao are set for each gear position.

The accelerator pedal 23 is a pedal that can be depressed even when the accelerator opening Ao exceeds fully open (100%). The accelerator opening sensor 22 detects the accelerator opening Ao and the fuel injection amount of the engine 11 or the like. Is configured by an electronically controlled type that is electronically controlled. In addition, although the accelerator pedal 23 of embodiment demonstrates the example of a suspension type pedal, you may comprise it with an organ type pedal. Further, in this accelerator pedal 23, the resistance to depression is gradually increased until the accelerator opening Ao exceeds fully opened and the kick down switch 24 is turned on, or the feeling of depression is made different when fully opened. At the same time, it is preferable that the sensation is further changed when the kick-down switch 24 is turned on beyond the fully open position. Thus, it is possible to notify the driver that the accelerator opening Ao is fully open, and further that when the accelerator opening Ao exceeds the full opening, the kick-down switch 24 is turned on.

  The accelerator pedal 23 is provided with a kick-down switch 24 in addition to an accelerator opening sensor 22 that detects an accelerator opening Ao. The kick-down switch 24 is an on / off switch that is turned off when the accelerator pedal 23 is depressed and the accelerator opening Ao does not exceed fully open, and is turned on when the accelerator opening Ao exceeds fully opened. It is configured.

  In this embodiment, an example is described in which the kickdown switch 24 is used to detect that the accelerator opening Ao exceeds fully open. However, instead of the kickdown switch 24, the accelerator opening whose setting has been changed is used. A degree sensor may be used. In the accelerator opening sensor instead of the kick down switch 24, the accelerator opening Ao is detected from a fully closed (0%) to a value exceeding the fully opened (100%) (for example, 110%), and the detected accelerator is detected. It is set so that the fully closed position of the opening Ao is output as fully closed, the fully opened value is output as a value less than fully opened (for example, 90%), and the value exceeding fully opened is output as fully opened. , Where 0% to 100% was used, is replaced with a range of 0% to 90%, and when 90% is exceeded, 100% is output. Further, when the accelerator opening sensor whose setting is changed instead of the kick down switch 24 is used, the setting of the control device 20 is also changed in the same manner as the change of the setting.

  When the accelerator pedal 23 is depressed beyond the full opening of the accelerator opening Ao and a kick down operation is performed to turn on the kick down switch 24, the control device 20 sets the selected gear position of the automatic transmission 14 one step. Control is performed to execute a downshift to shift to a gear stage with a high gear ratio.

  As described above, when the kick-down switch 24 provided on the accelerator pedal 23 configured to be able to be depressed even when fully opened is detected, it is detected that the kick-down operation has occurred. Downshift that accurately reflects the kickdown operation performed.

  In the control device of the prior art, when the kickdown operation is performed in a situation where the vehicle speed or the accelerator opening is in the vicinity of the upshift line, a so-called shift busy state occurs in which the upshift is performed immediately after the downshift. The fuel economy and drivability were getting worse.

  Therefore, in the control device 20 of the present invention, the high opening degree vehicle speed Vu2 that is the vehicle speed when the accelerator opening degree Ao is fully opened (100%) on the upshift line Lu set in the shift map M1 is shifted from the high opening degree vehicle speed Vu2 to the low vehicle speed side. A dead zone R having a preset vehicle speed width Δd in the direction of the vehicle speed axis Lb is provided, and when the kick down switch 24 is turned on in the dead zone R, a control for prohibiting a downshift of the gear stage is performed. When the kick down switch 24 is turned on at a vehicle speed lower than the range of R, control is performed to perform a downshift of the gear position.

FIG. 2 shows the shift map M1. In the shift map M1, a plurality of downshift lines Ld and a plurality of upshift lines Lu based on the vehicle speed V and the accelerator opening Ao are set for each shift stage. For example, when the automatic transmission 14 has the first to sixth speeds, five downshift lines Ld and five upshift lines Lu are set in the shift map M1.

  The downshift line Ld is set to have a shape in which the vehicle speed on the high opening side in the downshift line Ld is close to the low opening vehicle speed Vd1, in this embodiment, a linear shape parallel to the accelerator opening axis La. . The low opening vehicle speed Vd1 is the vehicle speed set to the fully open (0%) of the accelerator opening Ao, and the vehicle speed on the high opening side is the vehicle speed set to the fully open (100%) of the accelerator opening Ao. Yes, each is a vehicle speed determined in advance by experiments and tests.

  Thus, when the vehicle speed on the high opening side approaches the low opening vehicle speed Vd1, the vehicle speed V decelerates beyond the downshift line Ld, and the vehicle speed V is the low opening vehicle speed Vd1 and the high opening side vehicle speed. When the accelerator opening Ao reaches near full open, the gear G2 is downshifted to the gear G1 based on the downshift line Ld, otherwise the accelerator pedal 23 is opened to the accelerator pedal 23. Since the shift stage is downshifted only when a kickdown operation that is depressed beyond the fully open degree Ao occurs, that is, only when the kickdown switch 24 is turned on, the driver's intention The number of downshifts due to unintended kickdowns can be reduced by suppressing the occurrence of kickdown operations that are not performed, which is advantageous in improving fuel consumption and drivability.

  Further, since the shift stage of the automatic transmission 14 can be downshifted by a kickdown operation intended by the driver while traveling in the automatic shift mode, the shift map M1 prepared for a flat road can be used. On slopes, the kick-down operation can be used. As a result, it is possible to travel on the slope without using the shift map for the slope other than the shift map M1, and the control of the automatic transmission 14 can be prevented from being complicated.

  In the downshift line Ld, the high opening side vehicle speed that is the upper limit value of the vehicle speed V in the downshift line Ld is set to be lower than the low opening degree vehicle speed Vu1 that is the lower limit value of the vehicle speed V in the upshift line Lu. Is desirable. By setting in this way, it is possible to suppress a downshift of the gear stage contrary to the driver's intention between the vehicle speed on the high opening degree side and the vehicle speed Vu1 on the low opening degree.

  Further, as the vehicle speed on the high opening side becomes closer to the low opening vehicle speed Vd1, the downshift of the gear stage contrary to the driver's intention can be suppressed. Therefore, as in this embodiment, the accelerator opening Ao More preferably, the vehicle speed from fully closed (0%) to fully opened (100%) is made constant, that is, set to a linear shape parallel to the accelerator opening axis La in the shift map M1.

  By setting the downshift line Ld in a straight line in this way, even if the accelerator pedal 23 is operated in the vicinity of the downshift line Ld and the accelerator operation is not more than the full opening of the accelerator opening Ao, the downshift line Ld is reliably reduced by kickdown. Since the shift can be avoided, it is advantageous for suppressing the occurrence of kickdown not intended by the driver. In addition, the downshift line Ld can be formed in a flat shape with respect to the low opening vehicle speed Vd1, and the high opening vehicle speed Vu2 of the upshift line Lu can be lowered to the lower vehicle speed side. Can be planned. This increases the chances of operating the engine 11 in a region where the fuel consumption rate (SFC) is high, which is advantageous for improving fuel consumption.

Therefore, when the vehicle speed V decelerates beyond the downshift line Ld from the right side of the shift map M1, based on the downshift line Ld, that is, the downshift line Ld starts from the right side. When the vehicle is crossed to the left, it is downshifted to a gear having a gear ratio that is one step higher than the currently selected gear, and in a range between the downshift line Ld and the low opening vehicle speed Vu1 on the upshift line Lu. Even if the vehicle speed V changes, the shift stage is not downshifted, and only when the kick down switch 24 is turned on, the shift stage is shifted down to a shift stage having a gear ratio higher than the currently selected shift stage. .

  The upshift line Lu is set so that the high opening vehicle speed Vu2 on the high opening side of the accelerator opening Ao is higher than the low opening vehicle speed Vu1 on the low opening side. When Ao is in the low opening portion, it substantially overlaps the line indicating the low opening vehicle speed Vu1 set based on the gear position, and as the opening degree increases, the vehicle speed V increases toward the higher speed side. It is set to a curved shape so as to be Vu2.

  Therefore, the control device 20 is based on the upshift line Lu, when the vehicle speed V increases from the left to the right of the shift map M1 beyond the upshift line Lu, and from above to below the shift map M1. When the accelerator opening Ao exceeds the upshift line Lu and returns to the closing direction, an upshift is performed to a gear having a gear ratio that is one step lower than the currently selected gear.

  The dead zone R is provided on the low vehicle speed side from the high opening vehicle speed Vu2 which is the vehicle speed when the accelerator opening Ao on the upshift line Lu is fully opened. The value of the vehicle speed width Δd of the dead zone R in the direction of the vehicle speed axis Lb is determined in advance by experiments and tests when the accelerator pedal 23 is depressed beyond the full opening of the accelerator opening Ao, and the kick down switch 24 is turned on. When the gear shift downshift is executed by the above, it is preferable to set the shift range beyond the upshift line Lu immediately after the downshift so that the gear shift upshift is not performed.

  Next, the speed change method of the automatic transmission 14 performed by the control device 20 will be described. Here, G1 is one of the plurality of shift stages of the automatic transmission 14, G2 is a shift stage having a gear ratio that is one step lower than the shift stage G1, and the downshift line Ld is shifted from the shift stage G2 to the shift stage G1. The upshift line Lu is an upshift line from the gear stage G1 to the gear stage G2. Further, the driving situation in the shift map M1, that is, the depression operation of the accelerator pedal 23 is indicated by points A1 to A9.

  When the shift stage G2 is selected and the accelerator pedal 23 is depressed from the point A1 to the point A2, the downshift line Ld is not crossed and the kick down switch 24 is turned off. The device 20 does not shift the gear stage G2 of the automatic transmission 14.

  When the gear stage G2 is selected and the accelerator pedal 23 is depressed from the point A1 to the point A3, the accelerator opening Ao exceeds the fully open (100%), although it does not cross the downshift line Ld. Since the kick-down switch 24 is turned on at a vehicle speed lower than the range of the dead zone R, the control device 20 downshifts the gear stage G2 of the automatic transmission 14 to the gear stage G1.

  When the gear stage G2 is selected and the vehicle speed V is decelerated from the point A4 to the point A5, the kick-down switch 24 is turned off, but the control device 20 crosses the downshift line Ld. The shift stage G2 of the automatic transmission 14 is downshifted to the shift stage G1.

  When the gear stage G1 is selected, the vehicle speed V accelerates from point A6 to point A7 and crosses the upshift line Lu, so the control device 20 upshifts the gear stage G1 of the automatic transmission 14 to the gear stage G2. To do.

When the shift stage G2 is selected and the accelerator pedal 23 is depressed from the point A8 to the point A9, the accelerator opening Ao exceeds the full open (100%), and the kick down switch 24 is turned on. Since the points A8 and A9 are within the range of the dead zone R, the control device 20 does not shift the gear stage G2 of the automatic transmission 14.

  As described above, in the shift method of the automatic transmission 14, when the vehicle speed V decelerates beyond the downshift line Ld during traveling in the automatic shift mode, the shift stage G2 is based on the downshift line Ld. Is shifted down to the gear stage G1, and in other cases, the kick-down operation that is stepped on the accelerator pedal 23 beyond the full opening of the accelerator opening Ao is from the range of the dead zone R provided in the vicinity of the upshift line Lu. Only when it occurs at a low vehicle speed, the gear stage G2 is downshifted to the gear stage G1.

  2 indicate the state immediately after the downshift of the gear stage is executed by the kick-down operation generated in the dead zone R when the dead zone R of the prior art is not provided. In the prior art, when the gear stage G2 is selected and the accelerator pedal 23 is depressed from the point A8 to the point A9, the accelerator opening Ao exceeds fully open (100%) and the kick down switch 24 is Since the control device 20 is turned on, the control device 20 downshifts the gear stage G2 of the automatic transmission 14 to the gear stage G1. Since the vehicle speed V increases from point A9 to point A10 and the accelerator opening Ao returns, the control device 20 upshifts the shift stage G1 of the automatic transmission 14 to the shift stage G2 to cross the upshift line Lu. To do. Thus, in the prior art, when a kick-down operation occurs in the dead zone R, the shift is busy.

  On the other hand, in the control device 20 described above, even when the shift stage G2 is selected and the accelerator pedal 23 is depressed from the point A8 to the point A9, the shift stage G2 of the automatic transmission 14 is shifted as described above. Keep it as it is.

  That is, according to the control device 20 and the speed change method of the automatic transmission 14 of the present invention, the dead zone R is provided on the low vehicle speed side from the high opening vehicle speed Vu2 of the upshift line Lu set in the shift map M1. When the kick-down operation occurs in the dead zone R, the gear position can be prevented from being downshifted, so that it is possible to avoid an upshift immediately after the downshift. Accordingly, frequent shifting due to the kick-down operation can be suppressed during traveling in the automatic shifting mode, and fuel consumption and drivability can be improved.

  In the control device 20 described above, it is more preferable that the vehicle speed width Δd of the dead zone R is set based on the acceleration when it is assumed that the downshift of the gear stage is executed in the dead zone R.

  When a downshift of the gear position by a kickdown operation for turning on the kickdown switch 24 is executed, the gear shifts down to a gear position having a gear ratio that is one step higher than the currently selected gear position. Accordingly, the vehicle speed V at that time increases due to the acceleration based on the driving force by the downshifted gear. The acceleration can be obtained by dividing the difference between the driving force and the running resistance by the vehicle weight.

  The range that does not exceed the upshift line Lu immediately after the kick-down operation due to the increase in the vehicle speed V can be obtained in advance by experiments and tests. By setting the range as the value of the vehicle speed width Δd of the dead zone R, While avoiding shift busy more reliably, it is possible to easily reflect the kickdown operation by the driver's intention. The value of the vehicle speed width Δd of the dead zone R may be wide for the upshift line Lu from the gear stage with a high gear ratio, and narrow for the upshift line Lu from the gear stage with a low gear ratio. preferable.

DESCRIPTION OF SYMBOLS 10 Vehicle 14 Automatic transmission 20 Control apparatus 21 Vehicle speed sensor 22 Accelerator opening sensor 23 Accelerator pedal 24 Kick down switch Ao Accelerator opening La La Accelerator opening axis Lb Vehicle speed axis Ld Downshift line Lu Upshift line M1 Shift map V Vehicle speed Vd1 Low opening speed Vu2 High opening speed R Dead zone

Claims (4)

It has a shift map in which upshift lines and downshift lines based on the vehicle speed and the accelerator pedal opening of the accelerator pedal are set for each shift stage, and at the time of automatic shift, the shift map is used to change the shift stage of the automatic transmission. While performing control to execute upshift and downshift,
Connected to a kick-down switch provided on an accelerator pedal configured to be able to be depressed even when the accelerator opening exceeds the full opening, a kick-down operation is performed in which the accelerator pedal is depressed beyond the full opening of the accelerator opening. When the kick down switch is turned on, a control device for an automatic transmission that performs control to execute a downshift of the shift stage,
A dead zone having a preset vehicle speed width in the vehicle speed axis direction is provided from the high opening vehicle speed, which is the vehicle speed when the accelerator opening is fully opened in the upshift line, to the low vehicle speed side,
When the kick down switch is turned on in the dead zone, a control for prohibiting the downshift of the shift stage is performed,
A control apparatus for an automatic transmission, characterized in that when the kick-down switch is turned on at a vehicle speed lower than the dead zone, control is performed to perform a downshift of a gear stage.   2. The control device for an automatic transmission according to claim 1, wherein the vehicle speed width is set based on an acceleration when it is assumed that a downshift of a gear stage is executed in the dead zone.   The control apparatus for an automatic transmission according to claim 1 or 2, wherein the downshift line is set to have a shape in which the vehicle speed on the high opening side of the downshift line is brought close to the vehicle speed on the low opening side. In the automatic transmission shifting method of upshifting and downshifting the shift stage of the automatic transmission based on the downshift line and the upshift line set in the shift map based on the vehicle speed and the accelerator opening during the automatic shift,
When the vehicle speed decelerates beyond the downshift line, the shift stage is downshifted based on the downshift line,
In other cases, the kick-down operation that is stepped on the accelerator pedal beyond the full opening of the accelerator opening is a vehicle speed from the high opening vehicle speed that is the vehicle speed when the accelerator opening is fully opened in the upshift line to the low vehicle speed. A shift method for an automatic transmission, wherein the shift stage is downshifted only when it occurs at a lower vehicle speed than a dead zone provided on the side.

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