JP5119761B2 - Shift control device for automatic transmission - Google Patents

Description

  The present invention relates to a shift control device for an automatic transmission that includes a so-called kick-down switch that operates in accordance with a driver's accelerator operation and shifts to a larger gear ratio than at present.

  The driver of a vehicle equipped with an automatic transmission, for example, when performing overtaking acceleration or the like, drops to a lower gear stage (that is, with a larger gear ratio) and has a larger driving force. Hope to drive at. Such a shift can be performed by the driver by manually operating a shift lever or the like, and the automatic transmission can be executed by a driver. However, conventionally, in order to improve the convenience of the driver, the vehicle has been accompanied by the driver's accelerator operation. There exists a so-called kick-down switch that operates and lowers the automatic transmission to the lowest shift stage that can be selected at the vehicle speed at that time. Conventionally, automatic transmissions are provided with a shift control device that executes a downshift operation in response to such a downshift operation by the driver. For example, as such a shift control device, one disclosed in Patent Document 1 below is known. The shift control device disclosed in Patent Document 1 prepares in advance an initial state shift pattern and a kickdown shift pattern in which a larger gear ratio is more easily set, and when the kickdown switch is operated. The shift pattern is changed from the shift pattern for the initial state to the shift pattern for the kick down. In the initial state, the driver can easily perform a downshift to a low speed stage without operating the kick down switch. It is what I did.

Japanese Patent Laid-Open No. 11-344108

  However, the driver does not always want a state that is easily downshifted because it is in the initial state, and the driver wants the same downshift operation in the future because the kickdown switch is operated. Not necessarily. In other words, assuming that a specific accelerator pedal is operated, for example, the initial state shift pattern is set although it is desired that the downshift is performed only when triggered by its own operation. In some cases, a downshift unnecessary for the driver may be executed. In addition, if the driver wants to perform a fine downshift automatically even when the kickdown switch is not operated, if the kickdown shift pattern is set at that time, the driver can There is a possibility that automatic downshift will not be performed. That is, conventionally, a downshift operation that does not conform to the driver's intention is executed. For this reason, conventionally, there is a possibility that a downshift operation not intended by the driver may give an unnecessary feeling of acceleration of the vehicle, that is, increase driving force. In addition, conventionally, a downshift is not performed at the position intended by the driver, so that the required acceleration feeling of the vehicle cannot be obtained, that is, there is a risk that the driving force is insufficient.

  SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a shift control device for an automatic transmission capable of improving the disadvantages of the conventional example and executing a downshift operation in accordance with the driver's intention. .

In order to achieve the above object, according to the first aspect of the present invention, there is provided shift control means for shifting the gear ratio to a larger gear ratio than the present when the kick-down switch that operates in response to the accelerator operation of the driver is switched on. In a shift control device for an automatic transmission, when the vehicle speed is lower than a predetermined vehicle speed and the driver's accelerator operation is determined to be an early stepping operation, even if the kick-down switch is in a switch-off state, a larger transmission ratio If the kick-down switch is not switched on when the vehicle speed is equal to or higher than the predetermined vehicle speed, even if it is determined that the driver's accelerator operation is an early stepping operation, the gear ratio is changed to a speed ratio larger than that at present. The shift control means is configured so that it does not occur .

The shift control device for an automatic transmission according to the first aspect of the present invention is such that when the driver depresses the accelerator pedal quickly in such a vehicle speed range lower than the predetermined vehicle speed, even if the kick down switch is not operated, The machine can be downshifted. That is, this shift control device can reflect the driver's intention to request a downshift, that is, the accelerator pedal is quickly depressed. In addition, this shift control device does not downshift the automatic transmission even if the driver depresses the accelerator pedal quickly in the vehicle speed range above a predetermined vehicle speed unless the kick down switch is switched on. Along with this, it is possible to suppress a sense of incongruity and noise that cause the motor to rotate at a high speed.

According to the first aspect of the present invention, the maximum value of the accelerator opening in the kick-down switch-off region where the kick-down switch does not feel resistance is obtained, and the accelerator opening when the accelerator is fully opened is determined in the kick-down switch-off region. The shift control means is configured to correct the maximum accelerator opening.

The shift control device for an automatic transmission according to claim 1 makes it possible to feel the resistance of the kickdown switch with the sole immediately after the accelerator is fully opened, so that the driver operates the kickdown switch. It is possible to eliminate a sensuous shift between when it is felt that it has been made and when the downshift operation is actually executed in accordance with the operation of the kickdown switch.

The shift control device for an automatic transmission according to the present invention is not limited to when the driver operates the kickdown switch, but also when the accelerator pedal is quickly depressed, the automatic transmission downshift according to the operation. On the other hand, if the accelerator pedal is operated at a normal operation speed or a slow speed, for example, downshift control according to the driver's intention of the accelerator opening degree is possible. Also, in the vehicle speed range above the specified vehicle speed, even if the driver depresses the accelerator pedal quickly, the automatic transmission will not be downshifted unless the kick down switch is switched on. Can reduce the sense of discomfort and noise. The shift control device of the automatic transmission corrects the accelerator opening when the accelerator is fully opened to the maximum accelerator opening in the kick-down switch off region, so that the resistance of the kick-down switch is felt on the sole immediately after the accelerator is fully opened. Can be felt with the soles of the feet, eliminating the sensory gap between when the driver feels that the kick-down switch has been activated and when the down-shift operation has actually been performed as the kick-down switch is activated. Can do. That is, this shift control device can perform a downshift operation in accordance with the driver's intention.

  Embodiments of a shift control apparatus for an automatic transmission according to the present invention will be described below in detail with reference to the drawings. The present invention is not limited to the embodiments.

  An embodiment of a shift control device for an automatic transmission according to the present invention will be described with reference to FIGS.

  The automatic transmission 10 of FIG. 1 illustrated here is not limited in the number of stages, but is automatically switched to one shift stage selected from a plurality of shift stages, and the internal combustion engine is changed according to the gear ratio of the shift stages. A stepped member that transmits the output torque of the prime mover 20 to a drive wheel (not shown) is shown.

  Further, here, the automatic transmission 10 and the prime mover 20 are illustrated as being controlled by the electronic control unit (ECU) 1 shown in FIG. That is, the electronic control device 1 functions as a shift control device for the automatic transmission, and also functions as a control device that performs combustion control and the like of the prime mover 20. The electronic control unit 1 includes a CPU (Central Processing Unit) (not shown), a ROM (Read Only Memory) that stores a predetermined control program and the like, and a RAM (Random Access Memory) that temporarily stores the calculation result of the CPU. , And a backup RAM for storing information prepared in advance.

  Here, the shift control device (electronic control device 1) of the present embodiment is provided with shift control means for controlling the shift operation of the automatic transmission 10. The speed change control means of the present embodiment includes the amount of operation state (operation amount and operation speed) of the driver's accelerator pedal 31, the vehicle speed V at that time, or the rotational speed of an output shaft (not shown) of the automatic transmission 10 related thereto. (Hereinafter, referred to as “AT output shaft rotation speed”) No., the gear ratio (that is, the gear position) is selected. Therefore, a vehicle equipped with the automatic transmission 10 includes an accelerator pedal operation amount detection means for detecting the operation amount of the accelerator pedal 31, an accelerator pedal operation speed detection means for detecting the operation speed of the accelerator pedal 31, and a vehicle speed V. A vehicle speed detecting means for detecting the AT or an AT output shaft rotational speed detecting means for detecting the AT output shaft rotational speed No is provided.

  For example, the operation amount of the accelerator pedal 31 corresponds to the depression amount of the accelerator pedal 31 (that is, the movement amount of the accelerator pedal 31), the opening degree (so-called accelerator opening degree), or the like. Further, the operation speed of the accelerator pedal 31 corresponds to a depression speed of the accelerator pedal 31, a change amount of the accelerator opening per unit time (hereinafter referred to as “accelerator opening change amount”), and the like.

  In this embodiment, the accelerator opening is used as the operation amount of the accelerator pedal 31, and the accelerator opening change amount is used as the operation speed of the accelerator pedal 31. Therefore, here, the accelerator opening sensor 41 shown in FIG. 1 is used as the accelerator pedal operation amount detection means and the accelerator pedal operation speed detection means, and the electronic control device 1 that has received the detection signal uses the accelerator opening TAP1 and the accelerator opening. The degree change amount ΔTAP1 is obtained. As for the accelerator opening sensor 41, a high signal voltage is output as the accelerator opening TAP1 increases.

  For example, the shift control means of the electronic control unit 1 includes a signal voltage (hereinafter referred to as “accelerator fully open voltage”) Eo output from the accelerator opening sensor 41 when the accelerator is fully opened, and an accelerator opening sensor 41 when the accelerator is fully closed. And the signal voltage (hereinafter referred to as "accelerator operating voltage") Ed output from the accelerator opening sensor 41 when the driver operates the accelerator. Then, the accelerator opening degree TAP1 is obtained as a percentage from the following formula 1. Note that the accelerator fully open voltage Eo and the accelerator fully closed voltage Ec are previously known values specific to the combination of the accelerator pedal 31 and the accelerator opening sensor 41. Therefore, in the actual calculation, the accelerator operation voltage Ed is detected only. The opening degree TAP1 can be obtained.

    TAP1 = {(Ed−Ec) / (Eo−Ec)} × 100 (1)

  For example, if the accelerator pedal 31 is depressed from the accelerator opening degree TAP1a to the accelerator opening degree TAP1b during the time t, the shift control means calculates the accelerator opening change amount ΔTAP1 as shown in the following equation 2. Do.

    ΔTAP1 = (TAP1b−TAP1a) / t (2)

  Furthermore, the vehicle speed V has been required by various methods. For example, as one of them, a calculation method using information on the AT output shaft rotational speed No is known. That is, there is a correlation between the vehicle speed V and the AT output shaft rotational speed No. For this reason, in this embodiment, the shift control means is caused to execute the shift control using the information of the AT output shaft rotational speed No. Accordingly, here, the AT output shaft rotational speed detection sensor 42 shown in FIG. 1 as an AT output shaft rotational speed detection means is prepared, and the detection signal is transmitted to the electronic control unit 1.

  By the way, the automatic transmission 10 illustrated here has a so-called kick-down switch 32 that operates by depressing the accelerator pedal 31 deeper than when the accelerator is fully opened and shifts to a lower gear than the present. It is prepared. Therefore, when the kick-down switch 32 is switched on, a signal voltage (hereinafter referred to as “kick-down switch operating voltage”) Ekd higher than the accelerator fully open voltage Eo is output from the accelerator opening sensor 41. The accelerator opening degree TAP1 becomes a value larger than 100 (%) when the accelerator is fully opened. That is, in this embodiment, it is determined that the kick-down switch 32 is switched on when the accelerator operation voltage Ed reaches the kick-down switch operating voltage Ekd.

  The kick-down switch 32 may have at least a mechanism that gives a feeling that the switch has been pushed to the soles of the driver (for example, an elastic member such as a spring that gives a sense of resistance or moderation). Therefore, here, a separate switch on / off detection means such as the accelerator opening sensor 41 or the like is used. The kick-down switch 32 may turn on / off the switch by itself having an electrical contact, and transmit a switch-on signal voltage to the electronic control device 1 when the switch is turned on.

  However, in this embodiment, 100 (%) when the accelerator is fully opened is set to the maximum value so that the accelerator opening degree TAP1 having a value exceeding this is not calculated.

  Therefore, in this embodiment, an accelerator opening (hereinafter referred to as “shift control accelerator opening”) TAP1SFT used for performing shift control separately from the accelerator opening TAP1 by the driver is prepared, and this shift is performed. The shift control means is caused to execute shift control using the control accelerator opening TAP1SFT. Specifically, the shift control means of the present embodiment performs shift control using a shift control map using the shift control accelerator opening TAP1SFT and the AT output shaft rotational speed No as parameters.

  For example, FIG. 2 illustrates a shift control map between the shift speed P (n) and the shift speed P (n−1). The shift control map shown in FIG. 2 is a shift diagram in which shift lines representing boundaries between regions of the respective shift speeds P (n) and P (n−1) are shown. One of the gear positions P (n) and P (n-1) is selected according to the position of the shift point determined by the shift control accelerator opening TAP1SFT. That is, in this shift control map, the shift characteristic can be changed depending on the shape of the shift line.

  Here, the AT output shaft rotational speed No is decreased and the shift control accelerator opening TAP1SFT is increased so that the shift point exceeds the shift line from the region of the shift stage P (n) and the shift stage P (n When shifting to the region -1), a downshift to the gear stage P (n-1) is executed. In addition, here, during normal operation of the accelerator pedal 31 (here, all operations except when the accelerator pedal 31 is quickly depressed), the accelerator opening degree TAP1 by the driver is used as it is. The opening TAP1SFT is set (that is, TAP1SFT = TAP1). Here, the quick depression of the accelerator pedal 31 means that the driver depresses the accelerator pedal 31 at a speed faster than usual. In addition, the stepping speed for determining that the stepping is early may be set in advance with reference to the average normal stepping speed of various drivers. You may make it obtain | require with reference to the past depression speed.

  The shift control map is, for example, when the accelerator output is fully open (TAP1SFT = TAP1 = 100) when the AT output shaft rotational speed No is equal to or lower than the first rotational speed No1 shown in FIG. The current shift speed P (n) is downshifted to the shift speed P (n-1). On the other hand, when the AT output shaft rotational speed No is higher than the first rotational speed No1 and the accelerator pedal 31 is in a normal operation, this shift control map is obtained from the current shift speed P (n) even if the accelerator pedal 31 is fully opened. It is configured not to change.

  Further, the shift control means of this embodiment is configured to set the shift control accelerator opening TAP1SFT to “TAP1SFT (KD)” when the kick-down switch 32 is switched on. For this reason, the shift control map defines the shift control accelerator opening TAP1SFT (KD) when the kick-down switch is on. This shift control accelerator opening TAP1SFT (KD) is a value larger than “100 (%)” when the accelerator is fully opened.

  Here, in this embodiment, not only when such a change in the shift control accelerator opening TAP1SFT or the like is detected or when the kick down switch 32 is switched on, but also some other predetermined accelerator. A downshift is also performed when the driver operates the pedal 31. Specifically, here, when the accelerator pedal 31 is quickly depressed, this is judged as a downshift request by the driver, and the shift control means is caused to execute the downshift. For this reason, in order to downshift using the shift control map in that case, the accelerator opening TAP1 of the driver is corrected according to the degree of the early stepping operation, and a value larger than the accelerator opening TAP1. It is necessary to derive the shift control accelerator opening TAP1SFT.

  Therefore, in the shift control means of this embodiment, when the accelerator opening change amount ΔTAP1 is larger than a predetermined value (that is, the depression speed of the accelerator pedal 31 is faster than the predetermined speed), the driver wants to downshift. The accelerator opening degree TAP1 at that time is corrected to a large value. Here, the correction value is the accelerator opening TAP1SFT for shift control during the early stepping operation. For example, here, as a correction method at the time of the quick stepping operation, the accelerator opening degree TAP1 is multiplied by the quick stepping correction coefficient K (No, ΔTAP1) as shown in the following Expression 3.

    TAP1SFT = TAP1 × K (No, ΔTAP1) (3)

  The rapid tread correction coefficient K (No, ΔTAP1) is a coefficient larger than “1” that changes according to the AT output shaft rotational speed No and the accelerator opening change amount ΔTAP1, and for example, the AT output shaft rotational speed No is high. Further, the larger the accelerator opening change amount ΔTAP1, the larger the value. The early stepping correction coefficient K (No, ΔTAP1) may be derived using, for example, a correction coefficient map using the AT output shaft rotational speed No and the accelerator opening change amount ΔTAP1 as parameters.

  For this reason, the shift control means of the present embodiment includes the shift control accelerator opening TAP1SFT in accordance with the rapid depression of the accelerator pedal 31 even when the AT output shaft rotation speed No is higher than the first rotation speed No1. Exceeds the shift line (here, “110 (%)”), the current shift stage P (n) is downshifted to the shift stage P (n−1).

  Further, when the vehicle is traveling at a high speed, the engine speed after the downshift becomes high. Therefore, if the downshift is performed only by stepping on the accelerator pedal 31 quickly, there is a disadvantage that the driver feels uncomfortable. Therefore, here, in order to avoid the inconvenience, the shift control accelerator pedal opening TAP1SFT is prevented from being downshifted when the vehicle speed is higher than the predetermined vehicle speed (that is, when the AT output shaft rotational speed No is higher than the second rotational speed No2). Guard value TAP1SFT (G) is set. This guard value TAP1SFT (G) is smaller than the shift line (in this case, “120 (%)”) when the accelerator opening degree TAP1SFT for shift control is smaller than a predetermined vehicle speed that is not desired to be downshifted, and when the accelerator is fully open. Is set to a value larger than “100 (%)”. The guard value TAP1SFT (G) is smaller than the shift control accelerator opening TAP1SFT (KD) when the kick-down switch 32 is switched on. Further, on the lower speed side than the predetermined vehicle speed, a shift line is set at a position smaller than the guard value TAP1SFT (G).

  Hereinafter, the downshift operation of the shift control apparatus (electronic control apparatus 1) of the automatic transmission according to the present embodiment will be described with reference to the flowchart of FIG.

  First, the shift control means of the shift control apparatus according to the present embodiment obtains an accelerator opening change amount ΔTAP1 associated with the driver's operation of the accelerator pedal 31, and compares the accelerator opening change amount ΔTAP1 with a predetermined value X. (Step ST1).

  At this time, the accelerator opening change amount ΔTAP1 is determined by the accelerator opening TAP1a and TAP1b before and after the operation of the accelerator pedal 31 obtained from the detection signal (signal voltage) of the accelerator opening sensor 41 and the time during which the operation is performed. Calculation is performed by substituting t into Equation 2 above. Further, the predetermined value X is a threshold value for determining whether or not the accelerator pedal 31 is quickly depressed, and may be set based on, for example, the results of experiments or simulations performed in advance. In addition, since the speed of the quick depression operation of the accelerator pedal 31 may be different for each driver, the predetermined value X is corrected by learning from the preference, tendency, habit, etc. of the operation of the accelerator pedal 31 by the driver. You may make it make it.

  When it is determined in step ST1 that the accelerator opening change amount ΔTAP1 is equal to or less than the predetermined value X, that is, when it is determined that the normal operation is different from the early stepping operation, the shift control means The accelerator opening TAP1 (here, TAP1b) at that time is obtained as the shift control accelerator opening TAP1SFT during normal operation (step ST2).

  On the other hand, the shift control means determines that the AT detected from the AT output shaft rotational speed detection sensor 42 when the accelerator opening change amount ΔTAP1 is larger than the predetermined value X in step ST1 and is determined to be an early stepping operation. An early stepping correction coefficient K (No, ΔTAP1) corresponding to the output shaft rotational speed No and the accelerator opening change amount ΔTAP1 in step ST1 is obtained (step ST3). Then, the shift control means multiplies the accelerator opening TAP1 (here, TAP1b) at that time by the rapid step correction coefficient K (No, ΔTAP1), and shift control accelerator opening at the time of the quick step operation. TAP1SFT is obtained (step ST4).

  Subsequently, the shift control means determines whether or not the shift control accelerator opening TAP1SFT obtained in step ST4 is smaller than the guard value TAP1SFT (G) described above (step ST5). If it is determined that the shift control means is smaller than the guard value TAP1SFT (G), the shift control accelerator opening TAP1SFT is set as the shift control accelerator opening TAP1SFT during the early stepping operation. If it is determined (step ST6) that the guard value TAP1SFT (G) is not less than the guard value TAP1SFT (G), the shift control accelerator opening TAP1SFT at the time of a quick stepping operation is determined. (Step ST7).

  Thus, after obtaining the shift control accelerator opening TAP1SFT at the time of the normal operation or the early stepping operation, the shift control means of the present embodiment performs the final normal operation or The accelerator opening TAP1SFT for shift control at the time of a quick stepping operation is set. That is, the shift control accelerator opening degree TAP1SFT at the time of the normal operation or the early stepping operation obtained up to step ST7 is not a final set value but a provisional value. Accordingly, the shift control means first determines whether or not the kick down switch 32 is switched on (step ST8).

  Here, if it is determined that the kick-down switch 32 remains switched off, this shift control means determines the accelerator opening for shift control during normal operation or early stepping operation obtained up to step ST7. TAP1SFT is set as the shift control accelerator opening degree TAP1SFT at the time of final normal operation or early stepping operation, respectively (step ST9). On the other hand, if the shift control means determines that the kick down switch 32 is switched on, the shift control accelerator opening TAP1SFT (KD) when the kick down switch is on is finally determined. It is set as the accelerator opening TAP1SFT for speed change control during normal operation or early stepping operation (step ST10).

  Thereafter, the shift control means performs shift control of the automatic transmission 10 based on the shift control accelerator opening TAP1SFT at the time of the normal operation or the early stepping operation (step ST11). Hereinafter, the shift control will be described with a specific example. In the following description, it is assumed that the current shift speed is the shift speed P (n). In the following description, it is assumed that the AT output shaft rotational speed No has almost no fluctuation for convenience. However, when there is such fluctuation, the shift point is moved taking this into consideration and the shift control is performed accordingly. .

  First, the case of normal operation will be described.

  In this case, unless the kick-down switch 32 is turned on, the accelerator opening TAP1 of the driver is directly used as the shift opening accelerator opening TAP1SFT. For this reason, the shift control means when the kick down switch 32 is switched off automatically shifts to maintain the current shift stage P (n) if the shift point does not move from the area of the shift stage P (n). If the machine 10 is controlled and the shift point is moved from the region of the gear stage P (n) to the region of the gear stage P (n-1), the gear stage P (n) is shifted from the current gear stage P (n). The automatic transmission 10 is downshifted to (n-1). At this time, when the AT output shaft rotation speed No is higher than the first rotation speed No1, the shift point does not exceed the shift control accelerator opening TAP1SFT (= 100) when the accelerator is fully open. No. P (n) is maintained.

  On the other hand, when the kick down switch 32 is turned on, the shift control accelerator opening TAP1SFT (KD) when the kick down switch is turned on is set as the shift control accelerator opening TAP1SFT during normal operation. Therefore, the shift control means at this time downshifts the automatic transmission 10 from the current shift speed P (n) to the shift speed P (n−1) according to the state of the kick-down switch 32.

  Next, the case of an early stepping operation will be described.

  In this case, when the kick down switch 32 is turned on, the shift control means automatically shifts from the current shift speed P (n) to the shift speed P (n-1) as in the normal operation described above. Downshift 10

  On the other hand, for example, when the AT output shaft rotational speed No is equal to or lower than the first rotational speed No1, even if the accelerator opening TAP1 of the driver is not 100 (that is, the accelerator is fully opened), the shift control accelerator opening TAP1SFT is the accelerator. Since it is corrected to a value larger than the opening degree TAP1, the shift point may exceed the shift line. Therefore, at this time, the shift control means downshifts the automatic transmission 10 from the current shift speed P (n) to the shift speed P (n−1). In other words, the shift control device of this embodiment further operates the kick-down switch 32 even if the driver's accelerator opening TAP1 itself is not large enough to exceed the lower shift line than when the accelerator is fully open. Even if not, the downshift request can be determined when the driver depresses the accelerator pedal 31 quickly, and the shift stage can be set to one paragraph.

  Further, when the AT output shaft rotational speed No is higher than the first rotational speed No1 and equal to or lower than the second rotational speed No2, the shift control accelerator opening TAP1SFT may exceed 100, which could not be exceeded during normal operation. At this time, the shift control accelerator opening TAP1SFT is corrected to a value larger than the shift line (110), and the shift point may exceed the shift line as shown in FIG. Therefore, in this case, the shift control means downshifts the automatic transmission 10 from the current shift speed P (n) to the shift speed P (n−1). That is, the shift control device of the present embodiment further operates the kick-down switch 32 in an area where the shift line cannot be exceeded by the accelerator opening degree TAP1 itself during normal operation by the driver. Even if not, the downshift request can be determined when the driver depresses the accelerator pedal 31 quickly, and the shift stage can be set to one paragraph.

  Further, when the AT output shaft rotational speed No is higher than the second rotational speed No2, even if the shift control accelerator opening TAP1SFT may exceed 100, which could not be exceeded during normal operation, the upper limit is shown in FIG. As shown in FIG. 4, the guard value TAP1SFT (G) is used. At this time, since the shift control accelerator opening TAP1SFT cannot exceed the shift line (120) higher than the guard value TAP1SFT (G), the shift control means moves the automatic transmission 10 to the current shift stage P (n ). That is, the speed change control device of the present embodiment is configured such that if the AT output shaft rotational speed No is higher than a predetermined rotational speed (second rotational speed No2), the downshift is not executed unless the kick down switch 32 is operated. can do.

  As described above, according to the speed change control device of the present embodiment, the kick-down switch 32 is used in a low vehicle speed range equal to or lower than a predetermined vehicle speed (here, the vehicle speed when the AT output shaft rotation speed No is the second rotation speed No2). The automatic transmission 10 can be downshifted not only when the engine is operated, but also when the driver depresses the accelerator pedal 31 quickly. In other words, even if the kick-down switch 32 is in the switch-off state, the shift control device of this embodiment determines that this is a downshift request if the driver depresses the accelerator pedal 31 quickly. The gear position of the transmission 10 is lowered by one step. As a result, the shift control device can transmit the driving force of the prime mover 20 to the driving wheels at a low gear position in accordance with a request for increasing the driving force by the driver, that is, the quick depression operation of the accelerator pedal 31. Therefore, this speed change control device is referred to as an increase in driving force commensurate with the operation of the accelerator pedal 31, that is, a driving force deficiency that the driver cannot obtain an acceleration feeling of the vehicle. A situation can be avoided, and a downshift operation in accordance with the driver's intention can be executed.

  On the other hand, in a vehicle speed range higher than the predetermined vehicle speed, the automatic transmission 10 is not downshifted unless the kick down switch 32 is operated regardless of how fast the driver depresses the accelerator pedal 31. That is, the speed change control device of the present embodiment can be configured not to operate the kick down switch 32 in a high vehicle speed range and not to frequently downshift only by operating the accelerator pedal 31. Therefore, when comprised in this way, the uncomfortable feeling, noise, etc. which the motor | power_engine 20 becomes high rotation accompanying the downshift at the time of high-speed driving | running | working can be suppressed now.

  By the way, in the operation process of the kickdown switch 32, the kickdown switch starts to feel a different sense of resistance with the sole of the foot as the driver depresses the accelerator pedal 31, and the kickdown switch There is a kick-down switch operation instruction point that transmits a down-shift instruction signal to the shift control means when it is stepped further from the resistance-sensing point.

  That is, the kick-down switch operation instruction point is a point in time when the kick-down switch 32 is switched on. At that time, the above-described kick-down switch operation voltage Ekd is output from the accelerator opening sensor 41.

  Here, when the kick-down switch 32 is operated, in order to obtain a good feeling of operation of the accelerator pedal 31, it is possible to immediately feel the resistance of the kick-down switch 32 with the sole of the foot after the accelerator is fully opened. desirable. For this reason, in order to obtain such a feeling of operation, it is only necessary to match the kick-down switch resistance occurrence point when the accelerator is fully opened. That is, in this case, the kick down switch 32 and the like may be set so that the respective signal voltages from the accelerator opening sensor 41 that are output when the accelerator is fully opened and when the kick down switch resistance is sensed are the same.

  However, the kickdown switch 32, the accelerator opening sensor 41, and the like have variations in the components themselves and assembly, and depending on the tolerance variations, the output timing of the accelerator fully open voltage Eo and the kickdown switch resistance are not necessarily generated. The point may not match. For this reason, when the kickdown switch resistance point is reached before the accelerator is fully opened, the driver operates the kickdown switch 32 based on a different sense of resistance sensed by the soles. Despite recognizing that it is being made, there is a risk that it will not be kicked down in time to feel the resistance. In addition, if the kickdown switch resistance point comes later than when the accelerator is fully open, the driver thinks that kickdown will be performed after feeling the resistance on the sole of the foot, but he himself There is a risk that the kickdown will be performed before the intended time. In general, even if it is possible to reduce the tolerance variation to a certain extent, it is difficult to eliminate it. Conventionally, the latter state with a sense of incongruity is intentionally created in any of the cases. That is, in the prior art, as shown in FIG. 6, after the accelerator fully open voltage Eo is output, the accelerator pedal 31 is depressed to some extent and the kick-down switch resistance occurrence point appears. In other words, in the past, a dead zone in which the resistance to the sole does not fluctuate between the accelerator fully open and the kick down switch resistance occurrence point is set, and the resistance of the kick down switch 32 is felt after this dead zone. An area that can be used is created.

  In the present embodiment, it is possible to reliably downshift in a region where the AT output shaft rotational speed No is equal to or less than the first rotational speed No1 until a sense of resistance is felt at such a sole, while the accelerator pedal 31 is fully opened. In spite of the fact that there is a possibility that the sense of incongruity that a downshift has occurred may be increased even though it has not been stepped on until the kickdown switch 32 or the like has deteriorated over time, the dead zone has been expanded. The shift control device is configured so that the dead zone can be shortened during the operation in consideration of the above.

  Specifically, here, an area until the driver senses a change in resistance to the sole is defined as a switch-off area of the kick-down switch (hereinafter referred to as “kick-down switch-off area”). Learning is performed while watching the maximum value of the accelerator opening degree TAP1 in the kick-down switch-off region. Here, the shift control device is configured such that the learned value is the accelerator opening degree TAP1 (= 100) when the accelerator is fully opened, and the accelerator opening degree TAP1 at the kick-down switch resistance occurrence point. That is, here, the accelerator opening degree TAP1 when the accelerator is fully opened is corrected to the maximum accelerator opening degree TAP1 in the kick-down switch off region, and the kickdown switch resistance sensation generation point is obtained when the accelerator opening degree TAP1 is when the accelerator is fully opened. Configure to come. Hereinafter, the learning operation will be described with reference to the flowchart of FIG.

  First, in the shift control means of this embodiment, the accelerator operation voltage Ed (n) output from the accelerator opening sensor 41 is higher than the current accelerator full open voltage Eo and lower than the kick down switch operating voltage Ekd. It is determined whether or not there is (step ST21). That is, here, the predetermined value shown in the upper diagram of FIG. 8 indicates that the accelerator pedal 31 is stepped on deeper than the currently set accelerator fully open state but not depressed until the kick-down switch 32 is actuated. It is determined whether or not the accelerator opening degree TAP1 has reached within the range (the range of the dead zone and the range where the kick-down switch resistance is felt).

  This shift control means determines that the accelerator operating voltage Ed (n) is equal to or lower than the accelerator fully open voltage Eo or the kick down switch operating voltage Ekd, that is, the accelerator opening TAP1 is within the predetermined range. When it deviates from the inside, the process proceeds to step ST36, where the accelerator constant opening degree determination counter T and the learning start flag F are set to “0”, and the present process is temporarily ended.

The accelerator constant opening degree determination counter T is a counter that increments one by one when a temporary kick-down switch resistance generation voltage Es _as is newly set or held at the same value _as described later. The certain range is included between the time when the accelerator fully open voltage Eo is detected and the time when the kick-down switch operating voltage Ekd is detected, and is set to a width narrower than that, for example. The learning start flag F is a flag that is set when the accelerator opening degree TAP1 or the like is in a state worthy of performing this learning operation.

  On the other hand, when it is determined in step ST21 that the accelerator operation voltage Ed (n) is higher than the accelerator full open voltage Eo and lower than the kick down switch operating voltage Ekd, the shift control means makes the accelerator opening TAP1 substantially constant. It is determined whether or not it is kept. For example, here, it is determined whether or not the absolute value of the difference between the accelerator operation voltage Ed (n) and the previous accelerator operation voltage Ed (n-1) is smaller than a predetermined value (step ST22), the state of the accelerator opening degree TAP1 is determined. In this case, as long as the accelerator pedal 31 is operated by a person, it is difficult to maintain the accelerator opening degree TAP1 at a constant value. Therefore, a value close to “0” is set as the predetermined value. It is preferable.

  If the difference is greater than or equal to the predetermined value in step ST22 and it is determined that the accelerator opening degree TAP1 is not kept substantially constant, the shift control means proceeds to step ST36, where the accelerator constant opening degree determination counter T Then, the learning start flag F is set to “0”, and this processing is temporarily ended.

  When the difference is smaller than the predetermined value in step ST22 and it is determined that the accelerator opening degree TAP1 is kept substantially constant, the shift control means sets the learning start flag F. (That is, whether F = 1 or not) is determined (step ST23). In other words, when the determination in steps ST21 and ST22 is affirmative, the learning operation is in a minimum state worthy of performing this learning operation. Here, the first calculation of the learning operation or the second and subsequent calculations are performed. It is judged whether or not.

If it is determined in step ST23 that the learning start flag F is not set, the shift control means determines that the calculation is the first calculation, and uses the accelerator operation voltage Ed (n) in step ST21 as a temporary kick. The down switch resistance generation voltage Es _as is set (step ST24), the learning start flag F is set (step ST25), and the process proceeds to the following step ST28.

If it is determined in step ST23 that the learning start flag F is set, the shift control means determines that the calculation is performed for the second time or later, and the accelerator operation voltage Ed (n) in step ST21 is the current temporary value. It is determined whether or not the kickdown switch resistance generation voltage Es _as is greater than (step ST26). That is, here, it is determined whether or not the accelerator pedal 31 has been depressed to the kick-down switch resistance occurrence point.

If it is determined in step ST26 that the accelerator operation voltage Ed (n) is equal to or less than the temporary kick-down switch resistance generation voltage Es _as and it is determined that the depression of the accelerator pedal 31 is held constant or returned, The control means proceeds to step ST28 described below assuming that the current temporary kick-down switch resistance generation voltage Es _as is used as it is.

On the other hand, when it is determined in step ST26 that the accelerator operating voltage Ed (n) is larger than the temporary kick-down switch resistance generation voltage Es _as , the shift control means determines that the accelerator pedal 31 is further depressed. Then, the accelerator operation voltage Ed (n) is set as a temporary kick-down switch resistance generation voltage Es _as (step ST27), and the process proceeds to the following step ST28.

The shift control means of the present embodiment thus sets the temporary kick-down switch resistance generation voltage Es _as , and then increments the accelerator constant opening degree determination counter T by one (step ST28), and the accelerator constant. It is determined whether or not the opening determination counter T has exceeded a predetermined value (step ST29). The predetermined value may be set to 10 times, 20 times, or the like, but if too many times are set, the amount of depression of the accelerator pedal 31 changes greatly, and a negative determination is made in step ST21 or step ST22 above. Therefore, it is preferable to set an appropriate number of times with reference to the results of experiments and the like.

The shift control means returns to step ST21 when the accelerator constant opening degree determination counter T is equal to or smaller than the predetermined number in step ST29, and when the accelerator constant opening degree determination counter T exceeds the predetermined number, FIG. As shown in the upper diagram, the temporary kick-down switch resistance generation voltage Es _as set at this time is set to the provisional value Eo _pro of the accelerator fully open voltage (step ST30). That is, here, the boundary portion where the dead zone ends and the kickdown switch starts to feel resistance is set as the provisional value Eo _pro of the accelerator fully open voltage.

Then, the shift control means determines whether or not the provisional value Eo _{pro of the} accelerator full open voltage matches or does not match the accelerator full open voltage Eo set at the present time (step ST31).

If the provisional value Eo _pro of the accelerator full open voltage and the current accelerator full open voltage Eo coincide with each other in step ST31, the shift control means proceeds to step ST36, where the accelerator constant opening degree determination counter T and the learning start flag F Each of these is set to “0”, and this processing is finished once. That is, here, since the dead zone is already filled, the state shown in the lower diagram of FIG. 8 is not required, and the accelerator full open voltage Eo is not necessary, and this learning operation is temporarily ended.

On the contrary, if it is determined in step ST31 that the provisional value Eo _pro of the accelerator full open voltage and the current accelerator full open voltage Eo do not match, the shift control means uses the provisional value Eo _pro of the accelerator full open voltage. A provisional value TAP1SFT _pro for shift control during normal operation is obtained based on the following equation 4 (step ST32), and the accelerator opening TAP1SFT for shift control during normal operation at the current accelerator full open voltage Eo is calculated as follows: It calculates | requires based on Formula 5 (step ST33).

_{TAP1SFT pro = TAP1 pro = {(} Ed (n) -Ec) / (Eo pro -Ec)} × 100 ... (4)

    TAP1SFT = TAP1 = {(Ed (n) −Ec) / (Eo−Ec)} × 100 (5)

Then, the shift control means determines whether or not the shift speed corresponding to the shift control accelerator opening tentative value TAP1SFT _pro matches or does not match the shift speed corresponding to the shift control accelerator opening TAP1SFT (step ST34). .

If this shift control means determines that there is a mismatch in step ST34, the shift control means proceeds to step ST36, sets the accelerator constant opening determination counter T and the learning start flag F to “0”, and once ends this processing. That is, in this case, the automatic transmission 10 shifts by updating the accelerator fully open voltage Eo to a new value (here, the provisional value Eo _pro of the accelerator fully open voltage), so that such shift is avoided. This learning operation is finished as much as possible.

On the other hand, when it is determined that the values coincide in step ST34, the shift control means sets the provisional value Eo _pro of the accelerator full open voltage as a new accelerator full open voltage Eo (step ST35). That is, here, as shown in the lower diagram of FIG. 8, the accelerator full-open voltage Eo is updated from the previous value to the provisional value Eo _pro of the accelerator full-open voltage in step ST30, and is shown in the upper diagram of FIG. Dead zone is packed.

  Then, this shift control means initializes the accelerator constant opening degree determination counter T and the learning start flag F to “0”, respectively, and once ends this processing (step ST36).

  As described above, the speed change control device according to the present embodiment can close the dead zone that must be set first in consideration of tolerance variation after the start of operation. Therefore, the driver can feel the resistance of the kick-down switch 32 with the sole of the foot when the accelerator pedal 31 is depressed until the accelerator is fully opened, and the operation of the kick-down switch 32 is started from that point. be able to. That is, according to this speed change control device, it is not possible to downshift before feeling the resistance of the kick-down switch 32 on the sole of the foot, or not to downshift despite feeling the resistance, When a sense of resistance is felt on the soles of the feet, the kick-down switch 32 is actuated so that the automatic transmission 10 can be downshifted without a sense of incongruity according to the driver's intention. For this reason, this speed change control device eliminates a sensory deviation between when the driver feels that the kick-down switch 32 has been operated and when the down-shift operation is actually executed in accordance with the operation of the kick-down switch 32. It is possible to improve the operational feeling and operability of the downshift operation performed by operating the kickdown switch 32.

  In addition, if deterioration with time occurs in the kick down switch 32 or the like, a dead zone that has been filled may be generated again. However, the speed change control device according to the present embodiment performs the learning operation described above constantly or occasionally. Therefore, it is possible to prevent the generation of the dead zone due to such deterioration over time. For this reason, this shift control device can continuously perform the downshift of the automatic transmission 10 without feeling uncomfortable when the kick down switch 32 is operated.

  In the above-described embodiments, the stepped automatic transmission has been described as an example. However, the present invention described above can be applied to a continuously variable automatic transmission regardless of a belt type or a toroidal type. The same effect can be achieved.

  As described above, the shift control device for an automatic transmission according to the present invention is useful as a technique for executing a downshift operation in accordance with a driver's intention.

It is a figure which shows an example of a structure of the transmission control apparatus of the automatic transmission which concerns on this invention. It is a figure which shows an example of the shift control map between gear stage P (n) and gear stage P (n-1). 3 is a flowchart illustrating a shift control operation of a shift control device for an automatic transmission according to the present invention. FIG. 4 is an example of a shift control map between a shift speed P (n) and a shift speed P (n−1), and the accelerator is operated when the AT output shaft rotation speed is between the first rotation speed and the second rotation speed. It is a figure shown about an example of the shift point when a pedal is depressed quickly. FIG. 6 is an example of a shift control map between a shift speed P (n) and a shift speed P (n−1), and when the AT output shaft rotation speed is higher than the second rotation speed, the accelerator pedal is operated quickly. It is a figure shown about an example of the gear shift point at the time. It is a figure which shows an example of the relationship between the accelerator opening degree for shift control before performing learning operation | movement of an accelerator full open voltage, and an accelerator operation voltage. 3 is a flowchart illustrating an operation for learning an accelerator full open voltage in a shift control device for an automatic transmission according to the present invention. It is a figure which shows an example of the relationship between the accelerator opening degree for shift control, and accelerator operation voltage before and behind execution of learning operation | movement of an accelerator full open voltage.

Explanation of symbols

1 Electronic control device (shift control device)
DESCRIPTION OF SYMBOLS 10 Automatic transmission 31 Accelerator pedal 32 Kick down switch 41 Accelerator opening sensor 42 AT output shaft rotation speed detection sensor

Claims (1)

In a shift control device for an automatic transmission having shift control means for shifting to a larger gear ratio than the present when a kick-down switch that is operated in accordance with a driver's accelerator operation is switched on,
When the vehicle speed is lower than a predetermined vehicle speed and the driver's accelerator operation is determined to be an early stepping operation, the shift control means shifts to a higher gear ratio than the present even if the kick down switch is switched off. When the vehicle speed is equal to or higher than the predetermined vehicle speed and the kick-down switch is not switched on, even if it is determined that the driver's accelerator operation is an early stepping operation, the gear ratio is not changed to a speed ratio larger than the current one. And the maximum accelerator opening in the kick-down switch-off area where the kick-down switch does not feel resistance is obtained, and the accelerator opening when the accelerator is fully open is determined as the maximum accelerator opening in the kick-down switch-off area. shift control device for an automatic transmission, characterized in that is corrected to.

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