Vehicle shift control device

Abstract

The present invention provides a vehicle shift control device that can quickly switch to a driving range corresponding to the shift operation. [Solution] A vehicle shift control device configured to switch between predetermined driving ranges in response to the operation of a shift device operated by the driver to switch driving ranges when the driver is operating a brake operation unit operated by the driver to apply braking torque to the wheels, wherein the brake operation time for which the amount of brake pedal operation is 1 predetermined amount or more is 1 predetermined time or more (Yes in step S13), and the braking torque applied to the wheels according to the amount of brake pedal operation is 1 predetermined torque or more (Yes in step S15), the brake judgment is set to ON (step S16), and the switching of driving ranges between predetermined driving ranges is permitted.

Description

Technical Field

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[0001] This invention relates to a shift control device for a vehicle that switches the driving range according to an operation of a shift device by a driver.

Background Art

[0002] Patent Document 1 describes a control device for a vehicle configured to park the vehicle at a predetermined position without the driver operating when the range signal of a range select switch that can be switched by an operation of a shift lever or the like is the parking range and an automatic parking start switch is on. This control device is configured to switch the driving range only when the driver performs a shift operation intending to switch the driving range while automatically parking. Specifically, when the range select switch is other than the parking range and the foot brake is operated, it is configured to switch to the driving range corresponding to the range select switch.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The control device described in Patent Document 1 determines the driver's intention to interrupt automatic parking control based on the driver's brake operation. Therefore, it is thought that the system determines that braking has been performed when the driver continues to operate the brake device for a predetermined time or longer until the braking torque acting on the wheels exceeds a predetermined torque, and then switches the driving range. On the other hand, brake pedals usually have a so-called "play" between their initial position and the predetermined position, during which no braking torque is applied to the wheels. Consequently, there is an unavoidable delay from the start of brake pedal operation, due to the time it takes for the pedal to be operated to a degree sufficient to generate braking torque, and for that braking torque to exceed a predetermined torque. Therefore, if the shift operation and brake operation are started almost simultaneously, the driving range may not switch until it is determined that braking has been performed, which may cause discomfort to the driver.

[0005] This invention was made in view of the above-mentioned technical problems, and the object of this invention is to provide a vehicle shift control device that can quickly switch to a driving range corresponding to a shift operation. [Means for solving the problem]

[0006] To achieve the above objective, this invention provides a vehicle shift control device comprising a brake operating unit operated by the driver to apply braking torque to the wheels, and a shift device operated by the driver to switch between driving ranges, wherein when the driver operates the brake operating unit, the vehicle shift control device is configured to switch between predetermined driving ranges, including switching from a non-driving range in which the transmission of torque between the driving force source and the drive wheels is interrupted to a driving range in which the driving force source and the drive wheels transmit torque, switching from a forward driving range to a reverse driving range, and switching from the reverse driving range to the forward driving range, wherein the control device determines the switching of the driving range. The controller is equipped with a control unit that determines whether the brake control unit has been operated by determining whether the amount of operation of the brake control unit is equal to or greater than a predetermined first predetermined amount, and a braking determination unit that determines whether the braking torque applied to the wheel, determined according to the amount of operation of the brake control unit, is equal to or greater than a predetermined predetermined torque, and when the brake operation time for which the amount of operation of the brake control unit has been determined by the control unit to be equal to or greater than the first predetermined amount is equal to or greater than a predetermined first predetermined time, and the braking determination unit has been determined to be equal to or greater than the predetermined torque, the controller is characterized in that it permits switching between the predetermined driving ranges.

[0007] Furthermore, in this invention, the controller may permit switching between predetermined driving ranges if the braking time during which the braking torque acting on the wheel is determined to be equal to or greater than the predetermined torque by the braking determination unit is equal to or greater than a predetermined second predetermined time.

[0008] Furthermore, in this invention, the controller may reset the brake operation time when the driving range is switched or when the braking torque acting on the wheels falls below the predetermined torque.

[0009] Furthermore, in this invention, the shift device includes a momentary type shift device configured to select the driving range by moving a shift operation unit operated by the driver from a preset standby position to a range selection position for selecting the driving range, and to return the shift operation unit to the standby position when the driver releases operation of the shift operation unit, and the controller may reset the brake operation time when the shift operation unit returns from the range selection position to the standby position.

[0010] Furthermore, in this invention, the controller is configured to update the brake operation time each time the operation determination unit determines that the amount of operation of the brake operation unit is equal to or greater than the first predetermined amount, and the maximum time of the updated brake operation time may be set to a predetermined third predetermined time that is equal to or greater than the first predetermined time.

[0011] Furthermore, in this invention, the braking determination unit may determine that the braking torque acting on the wheel is equal to or greater than the predetermined torque when the amount of operation of the brake operation unit is greater than or equal to a predetermined second predetermined amount which is greater than the first predetermined amount. [Effects of the Invention]

[0012] The vehicle shift control device in this invention is configured to switch the driving range between predetermined driving ranges, including switching from a non-driving range to a driving range, and switching from a forward driving range to a reverse driving range, or from a reverse driving range to a forward driving range, in response to the operation of the shift device when the brake control unit is operated. Furthermore, the above-mentioned switching of the driving range is permitted when the brake operation time, during which it is determined that the amount of operation of the brake control unit is equal to or greater than a first predetermined amount, is equal to or greater than a first predetermined time, and when it is determined that the braking torque applied to the wheels, which is determined according to the amount of operation of the brake control unit, is equal to or greater than a predetermined torque.Therefore, the switching of the driving range can be permitted at the time when the braking torque applied to the wheels becomes equal to or greater than a predetermined torque, or relatively shortly after the braking torque applied to the wheels becomes equal to or greater than a predetermined torque.As a result, even if the shift device is operated relatively shortly after the brake control unit is started to be operated, the driving range can be switched according to the operation of the shift device, and the driver's discomfort can be suppressed. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a schematic diagram showing an example of a shift control device according to an embodiment of the present invention. [Figure 2] Figure 2 is a schematic diagram of a shift device, where (a) shows a shift device that selects the driving range according to the position of the shift lever, (b) shows a shift device that selects the driving range according to the rotation angle of the dial, and (c) shows a shift device that selects the driving range according to the operation of the paddle. [Figure 3] Figure 3 is a flowchart illustrating an example of control for determining the switching of the driving range. [Figure 4] Figure 4 is a flowchart illustrating an example of control that switches the brake detection flag to the ON position. [Figure 5]Figure 5 is a time chart illustrating the changes in driving range, braking torque, stop lamp switch, stop lamp duration, brake judgment flag, and shift lever position when switching the driving range from P range to D range. [Figure 6] Figure 6 is a time chart illustrating the changes in driving range, braking torque, stop lamp switch, brake judgment flag, and shift lever position when the stop lamp switch is stuck in the off position. [Modes for carrying out the invention]

[0014] This invention will be described based on the embodiments shown in the figures. The embodiments described below are merely examples of how this invention can be implemented and do not limit it.

[0015] An example of a vehicle according to an embodiment of this invention is shown in Figure 1. The vehicle Ve shown in Figure 1 is equipped with a drive source 1 such as an engine or a motor, and a transmission mechanism 2 connected to the drive source 1. This transmission mechanism 2 can be configured as a stepped transmission mechanism that changes the gear ratio between the drive source 1 and the drive wheels 3 in steps, or as a continuously variable transmission mechanism that changes the gear ratio continuously. Furthermore, as a continuously variable transmission mechanism, a belt-type continuously variable transmission mechanism that changes the gear ratio by changing the winding radius of the belt, a toroidal-type continuously variable transmission mechanism that changes the gear ratio by changing the inclination angle of the power roller, or an electric continuously variable transmission mechanism that is configured by a differential mechanism in which an input shaft, a motor, and an output shaft are connected, and changes the gear ratio by controlling the rotational speed of the motor can be employed.

[0016] Furthermore, the transmission mechanism 2 is configured to allow setting a drive range (D range) for forward driving by transmitting torque between the drive source 1 and the drive wheels 3, and a neutral range (N range) in which the transmission of torque between the drive source 1 and the drive wheels 3 is interrupted. Specifically, a clutch mechanism is provided between the drive source 1 and the drive wheels 3, and the D range is set by engaging the clutch mechanism, and the N range is set by disengaging the clutch mechanism. In the case of the electric continuously variable transmission mechanism described above, the D range is set by connecting an electrical circuit so that the motor and the energy storage device provided in the electric continuously variable transmission mechanism can exchange power, and the N range is set by interrupting the electrical circuit between the motor and the energy storage device. This D range corresponds to the "forward driving range" in the embodiment of this invention.

[0017] Furthermore, the transmission mechanism 2 is configured to set a reverse range (R range) for reverse driving by reversing the output torque of the drive force source 1 and transmitting it to the drive wheels 3. Specifically, a forward / reverse switching mechanism or a counter gear is provided, and the R range is set by changing the torque transmission path. Alternatively, as described above, another drive force source is provided on the output side of the transmission unit that changes the gear ratio, and the R range is set by stopping the drive force source 1 and outputting torque from the other drive force source in the opposite direction to the output torque when the drive force source 1 is operating. This R range corresponds to the "reverse driving range" in the embodiment of this invention.

[0018] Note that a parking lock mechanism (not shown) that prohibits the rotation of the rotating member is provided between the driving force source 1 and the driving wheel 3. This parking lock mechanism can be composed of a parking gear connected to the rotating member and a parking pole that meshes with the teeth of the parking gear to prohibit the rotation of the parking gear, similar to the parking lock mechanism provided in conventional vehicles. Then, by blocking the torque transmission between the driving force source 1 and the driving wheel 3 and prohibiting the rotation of the rotating member by the parking lock mechanism, a parking range (P range) is set. The above N range and P range correspond to the "non-driving range" in the embodiment of this invention.

[0019] In addition, a brake device 5 that generates a braking force by applying a frictional force is provided to the driving wheel 3 of the vehicle Ve shown in FIG. 1 and other wheels 4 (hereinafter, the driving wheel 3 and other wheels 4 may be collectively referred to as the wheel 4). The frictional force by this brake device 5 is configured to be controllable according to the operation amount of a brake pedal 6 operated by the driver. Specifically, for example, the brake device 5 is provided with a brake disk integrated with the wheel 4, and when the driver depresses the brake pedal 6 as a brake operation part, the clamping pressure for clamping the brake disk is controlled according to the depression amount and the depressing force to control the frictional force.

[0020] Therefore, the brake pedal 6 is provided with a sensor for detecting the operation amount of the brake pedal 6. Specifically, in order to detect that the brake pedal 6 has been depressed, there are provided a stop lamp switch 7 that is turned on when the brake pedal 6 is depressed, a brake sensor 8 that detects the depression amount (stroke amount) of the brake pedal 6, and a pedal force sensor 9 that detects the depressing force of the brake pedal 6. The depression amount of the brake pedal 6 when the stop lamp switch 7 is turned on corresponds to the 'first predetermined amount' in the embodiment of this invention. The braking device 5 may be a hydraulic brake that generates braking torque by hydraulic pressure, or an electric brake that generates braking torque by electromagnetic force. When the braking device 5 is a hydraulic brake, a sensor for detecting the hydraulic pressure of a master cylinder (not shown) that generates hydraulic pressure corresponding to the depressing force (pedal force) of the brake pedal 6 may be provided.

[0021] Furthermore, the vehicle Ve shown in FIG. 1 is provided with a shift device 10 that is operated by the driver to select a driving range. This shift device 10 is provided on the center console, instrument panel, etc., and is composed of a shift operation part operated by the driver and a detection part that detects the operation state including the operation position, operation angle, or number of operations of the shift operation part by the driver. In addition, the shift device 10 is provided with a return mechanism such as a spring (not shown), and is configured such that when the driver releases his hand from the operation part (releases the shift operation), the shift operation part returns from the range selection position for selecting the driving range to the standby position (Home). That is, the shift device 10 is composed of a so-called momentary type shift device 10. FIGS. 2(a) to 2(c) schematically show an example of the shift device 10 configured as described above.

[0022] The shift device 10 shown in Figure 2(a) consists of an H-shaped slot 11a formed in the center console or instrument panel, and a shift lever 11b that moves along the slot 11a. The slot 11a is provided with a B position, which is below the standby position (Home) of the shift lever 11b and is a range selection position for selecting the brake range (B range); an N position, which is to the right of the standby position and is a range selection position for selecting the N range; a D position, which is to the lower right of the standby position and is a range selection position for selecting the D range; and an R position, which is to the upper right of the standby position and is a range selection position for selecting the R range. Each of these positions is provided with a switch (not shown) for detecting when the shift lever 11b has moved. Specifically, there is a B switch that is turned on when the shift lever 11b moves to the B position, an N switch that is turned on when the shift lever 11b moves to the N position, a D switch that is turned on when the shift lever 11b moves to the D position, and an R switch that is turned on when the shift lever 11b moves to the R position.

[0023] Furthermore, the shift device 10 shown in Figure 2(a) is equipped with a parking button 11c as a shift operation unit and a parking switch (P switch) (not shown) that is turned on when the parking button 11c is pressed.

[0024] The shift device 10 shown in Figure 2(b) consists of a support shaft 12a provided on the center console or instrument panel, and a dial 12b, which serves as a shift operation part, that is rotatably mounted on the support shaft 12a and pressable in the direction of the central axis of the support shaft 12a. Specifically, the dial 12b is configured to rotate relative to the support shaft 12a when pressed. Furthermore, a return mechanism (not shown) is provided so that when the hand is released from the dial 12b, the rotation angle of the dial 12b relative to the support shaft 12a becomes a predetermined angle as the standby position (Home), and the tip surface of the support shaft 12a and the upper surface of the dial 12b become the same height.

[0025] Furthermore, the support shaft 12a or dial 12b is provided with an R position, which is the range selection position for selecting the R range when the dial 12b is pressed and rotated counterclockwise by a predetermined angle; a D position, which is the range selection position for selecting the D range when the dial 12b is pressed and rotated clockwise by a predetermined angle; and an N position, which is the range selection position for selecting the N range when the dial 12b is pressed. Each of these positions is provided with a switch (not shown) for detecting the position of the dial 12b. Specifically, there is an N switch that is turned on when the dial 12b is pressed, an R switch that is turned on when the dial 12b is rotated to the R position, and a D switch that is turned on when the dial 12b is rotated to the D position.

[0026] Furthermore, the shift device 10 shown in Figure 2(b) is also equipped with a parking button 12c as a shift operation unit and a parking switch (P switch) (not shown) that is turned on when the parking button 12c is pressed, similar to the shift device 10 shown in Figure 2(a).

[0027] The shift device 10 shown in Figure 2(c) consists of a linear slot 13a formed in the center console or instrument panel, and a paddle 13b that moves back and forth within the slot 13a as a shift operation unit. The slot 13a has five positions, starting from the top (front) side in Figure 2(c): the D position as a range selection position, the forward N position as a range selection position, the standby position, the rear N position as a range selection position, and the R position as a range selection position. These positions are separated by a joint that provides resistance (a knocking sensation) when operating the paddle 13b.

[0028] Furthermore, there is a D switch that is turned on when the paddle 13b moves to the D position, an N switch that is turned on when the paddle 13b moves to the forward N position, an N switch that is turned on when the paddle 13b moves to the rearward N position, and an R switch that is turned on when the paddle 13b moves to the R position.

[0029] Furthermore, a return mechanism (not shown) is provided so that the paddle 13b returns to the standby position (Home), which is the center of the slot 13a, when the user releases their hand from the paddle 13b. Although not shown in Figure 2(c) for convenience, a parking switch (P switch) is provided, similar to Figures 2(a) and 2(b).

[0030] As described above, the P range is a driving range in which the rotation of the rotating members is prohibited by the parking lock mechanism, and the vehicle can maintain a stationary state without applying braking torque to the wheels 4 by the brake device 5. In contrast, the other driving ranges are driving ranges in which the parking lock mechanism is released and the wheels 4 can rotate. Therefore, switching from the P range to other driving ranges is configured to be performed (permitted) only when braking torque is applied to the wheels 4 by the brake device 5.

[0031] Furthermore, in D and R ranges, the drive source 1 and the drive wheels 3 are connected to transmit torque, while in N range, the transmission of torque between the drive source 1 and the drive wheels 3 is interrupted. Therefore, switching the driving range from N range to a drive range including D or R range is performed (permitted) only when braking torque is applied to the wheels 4 by the brake device 5.

[0032] Furthermore, since the direction of torque transmitted to the drive wheels 3 is opposite for the D range and R range, switching the driving range from D range to R range, and from R range to D range, is also performed (permitted) when braking torque is applied to the wheels 4 by the brake device 5. In the following explanation, switching from P range to other driving ranges, switching from N range to a driving range, switching from D range to R range, and switching from R range to D range may be referred to as switching between predetermined driving ranges.

[0033] Therefore, the vehicle Ve shown in Figure 1 is equipped with a controller 14 for determining whether or not to allow switching between predetermined driving ranges. This controller 14 is mainly composed of a microcomputer and is configured to determine whether or not to allow switching between predetermined driving ranges based on the input signals and pre-stored calculation formulas. In the example shown in Figure 1, signals are input to the controller 14 from the stop lamp switch 7, brake sensor 8, pedal force sensor 9, and each sensor provided in the shift device 10.

[0034] Figure 3 shows a flowchart illustrating a control example for determining whether or not to allow switching between predetermined driving ranges. In the control example shown in Figure 3, first, it is determined whether or not there is a shift operation to switch between predetermined driving ranges (step S1). Specifically, it is determined whether or not another driving range is selected when the P range is set, whether or not the D range or R range is selected when the N range is set, whether or not the R range is selected when the D range is set, and whether or not the D range is selected when the R range is set, based on signals input to the controller 14 from a switch provided on the shift device 10.

[0035] If step S1 is negatively determined due to the absence of a shift operation to switch between predetermined driving ranges, the currently set driving range is retained (step S2), and this routine is terminated. However, if a shift operation is performed to switch between driving ranges other than those predetermined, the driving range may be changed based on that shift operation.

[0036] Conversely, if a positive result is obtained in step S1 due to a shift operation to switch between predetermined driving ranges, the shift operation time is counted up (step S3), and it is determined whether the shift operation time is equal to or greater than a predetermined time (step S4). The shift operation time in step S3 is the time during which the shift device 10 is continuously operated, that is, the time during which the switch in the shift device 10 is continuously turned on. Step S4 is a step to determine whether the driver operated the shift device 10 with the intention of switching driving ranges, and a predetermined time determined in advance through experiments or simulations is stored in the controller 14.

[0037] If the shift operation time is less than the predetermined time and is judged negatively in step S4, the system returns to step S1. Therefore, if the shift device 10 is operated unintentionally, such as when the driver's body comes into contact with the shift device 10, the system will be judged negatively in step S1 after the negative judgment in step S4. As a result, the driving range is maintained by executing step S2. Conversely, if the shift operation time is longer than the predetermined time and is judged positively in step S4, the system determines whether the brake judgment flag is on or off (step S5).

[0038] Figure 4 shows a flowchart illustrating a control example for switching the brake judgment flag to ON. Note that the control example shown in Figure 4 may be executed if a positive judgment is made in step S4 in Figure 3, or it may be executed in parallel with the control example shown in Figure 3.

[0039] In the control example shown in Figure 4, first, it is determined whether the stop lamp switch 7 is on or not (step S11). That is, it is determined whether the brake pedal 6 has been pressed down to a first predetermined amount that turns on the stop lamp switch 7. This step S11 functions as the "operation determination unit" in this embodiment of the invention. If it is determined positively in step S11 because the stop lamp switch 7 is on, the stop lamp time is counted up (step S12). That is, the stop lamp time is updated each time it is determined positively in step S11.

[0040] Next, it is determined whether the stop lamp time is equal to or greater than a predetermined first predetermined time (step S13). This step S12 is for determining whether the driver has operated the brake pedal 6 with the intention of switching the driving range, and the first predetermined time, which has been determined in advance by experiments or simulations, is stored in the controller 14. The stop lamp time corresponds to the "brake operation time" in this embodiment of the invention.

[0041] If step S13 is negatively determined because the stop lamp time is less than the first predetermined time, the brake judgment flag is set to off (step S14) and this routine is terminated. Conversely, if step S13 is positively determined because the stop lamp time is the first predetermined time or longer, it is determined whether the braking torque applied to the wheels 4, which is determined according to the amount of operation of the brake pedal 6, is greater than or equal to a predetermined torque (step S15). Step S15 is a step to determine whether a braking torque is applied to the wheels 4 to suppress the vehicle Ve from starting when the driving range is switched between predetermined driving ranges and torque is applied to the drive wheels 3. Therefore, the predetermined torque in step S15 is determined in advance by experiments or simulations and stored in the controller 14. Step S15 functions as the "braking judgment unit" in this embodiment of the invention.

[0042] Step S15 only needs to determine whether or not a braking torque of a predetermined torque or greater is being applied to the wheel 4. For example, it may be determined whether the brake pedal 6 has been operated beyond a predetermined amount such that the braking torque of the wheel 4, which is determined according to the amount of operation of the brake pedal 6, is equal to or greater than the predetermined torque. This predetermined amount of operation corresponds to the "second predetermined amount" in this embodiment of the invention. Furthermore, if the brake device 5 is a hydraulic brake, it may be determined whether or not the master cylinder pressure is equal to or greater than a predetermined pressure such that the braking torque of the wheel 4 is equal to or greater than the predetermined torque.

[0043] Here, the braking torque applied to the wheel 4 is determined by the amount and force applied to the brake pedal 6, and the stop lamp switch 7 is turned on by slightly pressing the brake pedal 6. Therefore, the amount of pressure applied to the brake pedal 6 when the stop lamp switch 7 is turned on is smaller than the amount of pressure applied to the brake pedal 6 when a positive judgment is made in step S15.

[0044] If step S15 is negatively determined because the braking torque applied to wheel 4 is less than a predetermined torque, switching the driving range between predetermined driving ranges may cause the vehicle Ve to start unintentionally, and if it starts in this way, it may not be possible to stop it immediately. Therefore, in this control example, if step S15 is negatively determined, the brake judgment flag is set to off (step S14), and this routine is terminated. Conversely, if step S15 is positively determined because the braking torque applied to wheel 4 is equal to or greater than the predetermined torque, the brake judgment flag is set to on (step S16), and this routine is terminated. In other words, switching the driving range between predetermined driving ranges is permitted.

[0045] On the other hand, in this control example, the system is configured to perform a brake determination even if a malfunction occurs in which the stop lamp switch 7 does not switch to the ON position (off-locked). Specifically, if a negative determination is made in step S11 because the stop lamp switch 7 is not ON, then, similar to step S15, it is determined whether the braking torque applied to the wheel 4, which is determined according to the amount of operation of the brake pedal 6, is equal to or greater than a predetermined torque (step S17). Note that the predetermined torque in step S15 and the predetermined torque in step S17 may be the same value.

[0046] If step S17 is negatively determined because the braking torque applied to wheel 4 is less than a predetermined torque, it is considered that the brake pedal 6 is not pressed, or that the braking torque required to prevent vehicle Ve from starting when the driving range switches between predetermined driving ranges and torque is applied to the drive wheels 3 is not being applied to wheel 4. In this case, the brake judgment flag is set to off (step S14) and this routine is terminated. Conversely, if step S17 is positively determined because the braking torque applied to wheel 4 is equal to or greater than a predetermined torque, the braking time is counted up (step S18) and it is determined whether the braking time is equal to or greater than the second predetermined time (step S19).

[0047] The braking time in step S18 is the time during which a braking torque equal to or greater than a predetermined torque is continuously applied to the wheels 4. Step S19 is a step to determine whether the driver is operating the brake pedal 6 to apply braking torque to the wheels 4 with the intention of switching the driving range, and a predetermined time determined in advance through experiments or simulations is stored in the controller 14.

[0048] If step S19 is negatively determined because the braking time is less than the second predetermined time, it is possible that the driver did not operate the brake pedal 6 with the intention of switching the driving range, such as when the brake pedal 6 was temporarily pressed. Therefore, in this control example, if step S19 is negatively determined, the brake judgment flag is set to off (step S14) and this routine is terminated. Conversely, if step S19 is positively determined because the braking time is the second predetermined time or longer, the brake judgment flag is set to on (step S16) and this routine is terminated. In other words, switching between predetermined driving ranges is permitted.

[0049] Based on the control example shown in Figure 4, a brake judgment flag is set, and based on the set brake judgment flag, step S5 in Figure 3 is determined. If step S5 is determined to be positive because the brake judgment flag is ON, the vehicle switches to the driving range selected by the shift device 10 (step S6), and the control example shown in Figure 3 is terminated. In other words, switching the driving range is permitted. Conversely, if step S5 is determined to be negative because the brake judgment flag is OFF, the currently set driving range is maintained (step S2), and this routine is terminated, because switching the driving range between predetermined driving ranges may cause the vehicle Ve to move unintentionally.

[0050] Figure 5 shows a time chart illustrating the changes in the driving range, braking torque applied to the wheels 4, stop lamp switch 7, stop lamp duration, brake judgment flag, and the position of the shift lever 10b when the shift device 10 is switched from the P position to the D position.

[0051] In the example shown in Figure 5, the P range is set at time t0, and the brake pedal 6 is not operated. Therefore, the braking torque and stop lamp duration are "0", and the stop lamp switch 7 and brake judgment flag are off.

[0052] At time t1, the brake pedal 6 is pressed and the braking torque begins to increase, and at time t2, the stop lamp switch 7 is turned on. As a result, the stop lamp duration begins to increase from time t2. Then, at time t3, the stop lamp duration exceeds the predetermined time. On the other hand, at time t3, the braking torque is less than the predetermined torque. As a result, at time t3, the brake judgment flag remains off, and at time t4, when the braking torque exceeds the predetermined torque, the brake judgment flag is switched on.

[0053] In the example shown in Figure 5, the brake detection flag is on (at time t5), the shift lever 10b is operated to the D position, and at time t6 the shift operation time exceeds a predetermined time. As a result, at time t6 the driving range has changed from P range to D range.

[0054] As described above, if the duration for which the stop lamp switch 7 is ON (stop lamp time) is for a predetermined time or longer, and the braking torque applied to the wheels 4 according to the amount of operation of the brake pedal 6 is equal to or greater than the predetermined torque, the brake judgment flag is switched ON to allow the switching of the driving range. This allows the switching of the driving range to be permitted at the moment the braking torque becomes equal to or greater than the predetermined torque, or relatively soon after the braking torque becomes equal to or greater than the predetermined torque. Therefore, even if a shift operation is performed relatively soon after the brake pedal 6 is started to be operated, the driving range can be switched to one that corresponds to that shift operation, and the driver's discomfort can be suppressed.

[0055] Furthermore, the control example shown in Figure 4 is configured to set the brake judgment flag to ON when the braking torque exceeds a predetermined torque for a period of time equal to or greater than the second predetermined time, even if the stop lamp switch 7 is OFF and a negative judgment is made in step S11. This takes into account the case where the stop lamp switch 7 fails to switch ON (off-fixed). Figure 6 shows a time chart to explain the changes in the driving range, braking torque applied to the wheels 4, brake judgment flag, and the position of the shift lever 11b when the shift device 10 is switched from the P position to the D position while the stop lamp switch 7 is stuck in the off position.

[0056] In the example shown in Figure 6, the P range is set at time t10, and the brake pedal 6 is not operated. Therefore, the braking torque is "0", and the stop lamp switch 7 and brake judgment flag are off.

[0057] Furthermore, in the example shown in Figure 6, because the stop lamp switch 7 is stuck in the off position, the stop lamp switch 7 does not switch on even when the brake pedal 6 is pressed and the braking torque increases after time t10. Then, at time t12, after a predetermined time has elapsed since the braking torque exceeded a predetermined torque (time t11), the brake judgment flag is switched on.

[0058] Then, with the brake detection flag turned on (at time t13), the shift lever 11b is operated to the D position, and at time t14, the shift operation time exceeds the predetermined time. As a result, the driving range is changed from P range to D range.

[0059] As described above, if the braking torque applied to the wheel 4, determined according to the amount of operation of the brake pedal 6, is equal to or greater than a predetermined torque for a duration (braking time) of a predetermined time or longer, the brake judgment flag is switched to ON, allowing the switching of the driving range. This allows the switching of the driving range to be performed even if the stop lamp switch 7 is stuck in the OFF position. In other words, it can function as a backup for the control that allows the switching of the driving range based on the stop lamp time.

[0060] Furthermore, it is preferable that the stop lamp time mentioned above be counted starting when the stop lamp switch 7 switches from off to on. By making the dynamic change of the stop lamp switch 7 from off to on the starting condition for counting the stop lamp time, it is possible to suppress the counting of the stop lamp time in the event of a malfunction (on-sticking) in which the stop lamp switch 7 turns on even though the brake pedal 6 is not pressed when the power to the vehicle Ve is started. As a result, it is possible to suppress the unintended permission to switch driving ranges when the driver temporarily presses the brake pedal 6 without intending to switch driving ranges and the braking torque exceeds a predetermined torque.

[0061] Furthermore, it is preferable to reset the stop lamp time when at least one of the following conditions is met: the driving range has been switched, the shift lever 11b is in the standby position, the braking torque has fallen below a predetermined torque, and the stop lamp switch 7 is off. By defining the conditions for resetting the stop lamp time in this way, it is possible to prevent the stop lamp time from being counted even after the brake pedal 6 has been released if the stop lamp switch 7 becomes stuck in the "on" position after the brake pedal 6 has been pressed and the stop lamp switch 7 has been turned on. As a result, it is possible to prevent unintended switching of the driving range from being permitted when the driver temporarily presses the brake pedal 6 without intending to switch the driving range, causing the braking torque to exceed a predetermined torque.

[0062] Furthermore, in the control example described above, the stop lamp time is counted up when the stop lamp switch 7 is ON. That is, it is stored in the RAM (Random Access Memory) provided in the controller 14. On the other hand, if the stop lamp time is longer than a predetermined time, there is no need to count up the stop lamp time any further. Therefore, when the stop lamp time reaches a predetermined upper limit time that is longer than a predetermined time, it is preferable to fix it to the upper limit time and stop counting up the stop lamp time until the above reset condition is met. By setting an upper limit time for the stop lamp time in this way, it is possible to suppress an increase in the RAM usage capacity. This upper limit time corresponds to the "third predetermined time" in the embodiment of this invention.

[0063] In this embodiment of the invention, the vehicle may be a conventional vehicle equipped only with an engine as a driving force source, an electric vehicle equipped only with a motor as a driving force source, or a hybrid vehicle equipped with both an engine and a motor as driving force sources, and the type of vehicle is not limited.

[0064] Furthermore, as mentioned above, the system may be configured to switch the driving range not only when a shift operation is performed after the brake detection flag has been turned on, but also when the brake detection flag is turned on while a shift operation has been performed. In other words, the order of the shift operation and the brake operation is not limited.

[0065] Furthermore, the "operation determination unit" in this embodiment of the invention may determine whether the brake pedal 6 has been pressed down by setting a predetermined amount smaller than the amount of depression at which the braking torque corresponding to the amount of depression of the brake pedal 6 becomes less than a predetermined torque, rather than limiting the operation amount of the brake pedal 6 at the time the stop lamp switch 7 is turned on. [Explanation of symbols]

[0066] 1. Power source 2. Transmission mechanism 3 drive wheels 4 wheels 5. Brake system 6. Brake pedal 7 Stop lamp switch 8. Brake sensor 9. Pedal force sensor 10 Shift device 11a, 13a slots 11b Shift lever 11c, 12c Parking button 12a Support shaft 12b Dial 13b Paddle 14 Controllers Vehicle

Claims

1. A vehicle shift control device comprising a brake operating unit operated by the driver to apply braking torque to the wheels, and a shift device operated by the driver to switch between driving ranges, wherein when the driver operates the brake operating unit, the vehicle shift control device is configured to switch between predetermined driving ranges, including switching from a non-driving range in which torque transmission between the drive source and the drive wheels is interrupted to a driving range in which torque is transmitted between the drive source and the drive wheels, switching from a forward driving range to a reverse driving range, and switching from the reverse driving range to the forward driving range, in response to the operation of the shift device, The system includes a controller that determines the switching of the aforementioned driving range, The aforementioned controller, An operation determination unit that determines whether the brake operation unit has been operated when the amount of operation of the brake operation unit is equal to or greater than a predetermined first amount, The system includes a braking determination unit that determines whether the braking torque applied to the wheel, determined according to the amount of operation of the brake operating unit, is equal to or greater than a predetermined torque. If the brake operation time for which the operation amount of the brake operation unit is determined to be equal to or greater than the first predetermined amount is equal to or greater than a predetermined first predetermined time, and the braking determination unit determines that the braking torque acting on the wheel is equal to or greater than the predetermined torque, then the switching of the driving range between the predetermined driving ranges is permitted. A vehicle shift control device characterized by the following features.

2. A vehicle shift control device according to claim 1, The aforementioned controller, If the braking time during which the braking torque acting on the wheel is determined to be equal to or greater than the predetermined torque by the braking determination unit is equal to or greater than a predetermined second predetermined time, the switching of the driving range between the predetermined driving ranges is permitted. A vehicle shift control device characterized by the following features.

3. A vehicle shift control device according to claim 1, The aforementioned controller, The brake operation time is reset when the aforementioned driving range is switched or when the braking torque acting on the wheels falls below the predetermined torque. A vehicle shift control device characterized by the following features.

4. A vehicle shift control device according to claim 1, The shift device includes a momentary type shift device configured such that a shift operation unit, operated by the driver, is moved from a preset standby position to a range selection position for selecting the driving range, and the shift operation unit returns to the standby position when the driver releases operation of the shift operation unit. The aforementioned controller, When the shift operation unit returns from the range selection position to the standby position, the brake operation time is reset. A vehicle shift control device characterized by the following features.

5. A vehicle shift control device according to any one of claims 1 to 4, The aforementioned controller, The brake operation time is updated each time the operation determination unit determines that the amount of operation of the brake operation unit is equal to or greater than the first predetermined amount. The maximum time of the updated brake operation time is set to a predetermined third predetermined time that is equal to or greater than the first predetermined time. A vehicle shift control device characterized by the following features.

6. A shift control device according to claim 1, The braking determination unit determines that the braking torque acting on the wheel is equal to or greater than the predetermined torque when the amount of operation of the brake operation unit is greater than or equal to a predetermined second predetermined amount which is greater than the first predetermined amount. A vehicle shift control device characterized by the following features.

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