Speed limiting device, speed limiting method, and storage medium containing speed limiting program

Abstract

The present invention relates to a vehicle speed limiter, a vehicle speed limiter method, and a storage medium containing a vehicle speed limiter program. The vehicle speed limiter (1) includes a control device having a first vehicle speed limiter function and a second vehicle speed limiter function, and a first cancellation function for disabling the first vehicle speed limiter function when a first accelerator pedal condition related to an operation of a predetermined operating unit is satisfied when the speed of the host vehicle matches a first speed (vs1). The control device includes a first forced cancellation function and a second forced cancellation function for disabling at least one of a first forced cancellation function and a second forced cancellation function, wherein the first forced cancellation function forcibly disabling the second vehicle speed limiter function when the time elapsed from a first time point at which the first vehicle speed limiter function is disabled by the first cancellation function to a second time point at which the speed of the host vehicle reaches a second speed is less than a predetermined threshold value and the first operating unit condition is satisfied at the second time point, and the second forced cancellation function forcibly disabling the second vehicle speed limiter function when the difference between the first speed and the second speed is less than a predetermined threshold value and the first operating unit condition is satisfied at the second time point after the first vehicle speed limiter function is disabled by the first cancellation function.

Description

Technical Field

[0001] The present invention relates to a vehicle speed limiter, a vehicle speed limiter method, and a vehicle speed limiter program that are mounted on a vehicle and control a driving device and / or a braking device of the vehicle so that the speed of the vehicle does not exceed a threshold value. Background Art

[0002] A vehicle speed limiter is known that is mounted on a vehicle and controls the vehicle's drive and / or brake system so that the vehicle's speed does not exceed a threshold value (for example, see Patent Document 1 below). The vehicle speed limiter disclosed in this patent document (hereinafter referred to as the "conventional device") has a first speed limit function that controls the vehicle's drive and / or brake system so that the vehicle's speed does not exceed a first speed (a method of driving at a constant speed at a target speed). Furthermore, the conventional device has a second speed limit function that controls the vehicle's drive and / or brake system so that the vehicle's speed does not exceed a second speed (greater than the first speed) (a method of not exceeding an upper limit speed).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2009-166542 Summary of the Invention

[0006] In a speed limiter device having a first speed limit function and a second speed limit function, as in conventional devices, it is preferable to include a first cancellation function that disables the first speed limit function when a first condition is met, and a second cancellation function that disables the second speed limit function when a second condition is met. In this case, if the driver operates (drives) in a manner that satisfies the first condition, the vehicle can accelerate beyond the first speed. Furthermore, if the driver operates (drives) in a manner that satisfies the second condition, the vehicle can accelerate beyond the second speed. Generally, as long as the first and second speed limit functions can be independently disabled when the first and second conditions are met, respectively, there is no problem. On the other hand, in special circumstances (e.g., avoiding an obstacle), it is preferable to be able to quickly disable the first and second speed limit functions. In such circumstances, it is troublesome for the driver to establish different conditions to disable each speed limit function, and this may prevent the driver from achieving the purpose of the special situation (e.g., avoiding an obstacle). Therefore, in special situations, it is preferable that the second vehicle speed limit function be disabled more easily than in normal cases after the first vehicle speed limit function is disabled.

[0007] An object of the present invention is to provide a speed limiter having a first speed limit function and a second speed limit function, wherein, under special circumstances, the speed limiter can disable the second speed limit function more easily than under normal circumstances after disabling the first speed limit function.

[0008] In order to solve the above-mentioned problems, a vehicle speed limiter (1) of the present invention is mounted on the vehicle.

[0009] The speed limiter device has:

[0010] an operating portion sensor (22) for detecting an operating mode of an operating portion operated by a driver when accelerating the vehicle;

[0011] A speed sensor (21) for detecting the speed (vs) of the vehicle;

[0012] A control device having a first vehicle speed limiting function, a first cancellation function, a second vehicle speed limiting function, and a second cancellation function, wherein the first vehicle speed limiting function is a function of controlling either or both of a driving device (30) and a braking device (40) of the vehicle so that the speed does not exceed a first speed (vs1), the first cancellation function is a function of invalidating the first vehicle speed limiting function when a first operating unit condition (A1) related to the operation of the operating unit is satisfied under a condition that the speed of the vehicle is consistent with the first speed, the second vehicle speed limiting function is a function of controlling either or both of a driving device and a braking device of the vehicle so that the speed of the vehicle does not exceed a second speed (vs2) which is higher than the first speed, and the second cancellation function is a function of invalidating the second vehicle speed limiting function when a second operating unit condition (A2) related to the operation of the operating unit is satisfied under a condition that the speed of the vehicle is consistent with the second speed.

[0013] The control device has a first forced cancellation function and a second forced cancellation function.

[0014] The first forced cancellation function is a function for forcibly disabling the second speed limit function when an elapsed time (t) from a first time point at which the first speed limit function is disabled by the first cancellation function to a second time point at which the speed of the host vehicle reaches the second speed is less than a predetermined threshold value (tth), and the first operating portion condition is satisfied at the second time point.

[0015] The second forced cancellation function is a function for forcibly disabling the second vehicle speed limit function if the first operating unit condition is satisfied at the second time point after the first vehicle speed limit function is disabled by the first cancellation function, when the difference between the first speed and the second speed is smaller than a predetermined threshold value (vsth).

[0016] Here, the first operating unit condition is satisfied, for example, when the accelerator pedal's depression depth exceeds a first depth for a duration exceeding a first time. Furthermore, the second operating unit condition is satisfied, for example, when the accelerator pedal's depression depth exceeds a second depth for a duration exceeding a second time. Furthermore, the first operating unit condition is satisfied, for example, when the rate of increase (% / second) of the accelerator pedal's depression depth exceeds a first rate of increase. Furthermore, the second operating unit condition is satisfied, for example, when the rate of increase (% / second) of the accelerator pedal's depression depth exceeds a second rate of increase.

[0017] In the present invention, when the time from the first time point to the second time point is relatively short and the first operating unit condition is satisfied at the second time point, even if the second operating unit condition is not satisfied, the second speed limit function is invalidated by the first forced cancellation function. In addition, when the difference between the first speed and the second speed is small, the necessity of providing two speed limit functions (the first speed limit function and the second speed limit function) is low. Here, in the present invention, when the difference between the first speed and the second speed is less than a threshold value, the second speed limit function is invalidated by the second forced cancellation function under the same conditions as those for invalidating the first speed limit function (i.e., the first operating unit condition). As described above, according to the present invention, under special circumstances, the driver can invalidate the second speed limit function more easily than under normal circumstances.

[0018] In a vehicle speed limiter according to one embodiment of the present invention,

[0019] The first forced cancellation function is a function forcibly disabling the second vehicle speed limit function when the elapsed time from the first time point to the second time point is less than a predetermined threshold and the first operating portion condition continues to be satisfied from the first time point to the second time point.

[0020] In a vehicle speed limiter according to another aspect of the present invention,

[0021] The second forced cancellation function is a function for forcibly disabling the second vehicle speed limit function when the difference between the first speed and the second speed is smaller than a predetermined threshold value and when the first operating portion condition continues to be satisfied from the first time point to the second time point.

[0022] In these embodiments, if the first operating unit condition is temporarily not satisfied between the first time point and the second time point, the second operating unit condition needs to be satisfied in order to cause the host vehicle to travel at a speed higher than the second speed. This prevents the host vehicle from being overaccelerated after the vehicle's speed exceeds the first speed.

[0023] Furthermore, the speed limiting method and program according to the present invention include steps executed by the various devices constituting the aforementioned speed limiting device. According to these methods and programs, the driver can disable the second speed limiting function more easily than usual under special circumstances. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a block diagram of a vehicle speed limiter according to one embodiment of the present invention.

[0025] Figure 2 This is a graph showing changes in the accelerator pedal's depression depth and the vehicle's speed.

[0026] Figure 3 Flowchart of a program for implementing the first vehicle speed limit function.

[0027] Figure 4 Flowchart of a program for implementing the second vehicle speed limit function.

[0028] Figure 5 Flowchart of a program for realizing the first cancel function.

[0029] Figure 6 Flowchart of the program for realizing the second cancel function. DETAILED DESCRIPTION

[0030] (Overview of the structure)

[0031] like Figure 1 As shown, a speed limiter 1 according to one embodiment of the present invention is mounted on a vehicle V. As described in detail below, the speed limiter 1 has two speed limit functions and a cancellation function that disables these two speed limit functions. Furthermore, to distinguish it from other vehicles, a vehicle equipped with the speed limiter 1 is sometimes referred to as a "host vehicle."

[0032] (Specific structure)

[0033] like Figure 1 As shown, the vehicle speed limiter 1 includes a vehicle speed limiter ECU 10 , an onboard sensor 20 , a drive device 30 , and a brake device 40 .

[0034] The speed limit ECU 10 includes a microcomputer including a CPU, ROM, RAM, a timer, and other components. In this specification, "ECU" refers to an electronic control unit (ECU), and includes a microcomputer including a CPU, ROM, RAM, and other components. The CPU executes instructions stored in the ROM to implement various functions.

[0035] The vehicle speed limit ECU 10 is connected to other ECUs (a motor ECU 31 and a brake ECU 41 to be described later) via a CAN (Controller Area Network) so as to be able to transmit and receive information to and from each other.

[0036] The vehicle-mounted sensors 20 include sensors that acquire information related to the running state of the vehicle V and the operation mode of operating elements (such as the speed of the vehicle and the operation mode of the accelerator pedal).

[0037] Specifically, the vehicle-mounted sensor 20 includes a speed sensor 21 , an accelerator pedal sensor 22 , and a switch 23 .

[0038] The speed sensor 21 includes a wheel speed sensor that generates a pulse signal (wheel pulse signal) each time a wheel of the vehicle rotates a predetermined angle. The speed sensor 21 measures the number of pulses per unit time in the wheel pulse signal transmitted from the wheel speed sensor and calculates the rotational speed (wheel speed) of each wheel based on the measured pulse number. Furthermore, the speed vs (actual vehicle speed) of the vehicle is calculated based on the wheel speed of each wheel. The speed sensor 21 transmits data representing the speed vs to the speed limit ECU 10.

[0039] The accelerator pedal sensor 22 detects the depression depth AD of the accelerator pedal (not shown) of the vehicle V. The accelerator pedal sensor 22 transmits data indicating the depression depth AD of the accelerator pedal to the speed limit ECU 10. The speed limit ECU 10 sequentially acquires the depression depth AD and stores it in a RAM (ring buffer). Based on the data stored in the ring buffer, the speed limit ECU 10 can identify changes in the accelerator pedal depression depth AD.

[0040] The switch 23 includes a push-button switch, a rotary encoder, and the like for the driver to determine a limit value (upper limit value (hereinafter referred to as “first speed vs1”)) of the speed of the host vehicle.

[0041] The drive unit 30 generates driving force and applies it to the drive wheels (left front wheel, right front wheel, left rear wheel, and right rear wheel). The drive unit 30 includes a motor ECU 31, a drive circuit 32, an electric motor 33, and a drive force transmission mechanism (not shown) that transmits the driving force to the wheels. The motor ECU 31 is connected to the drive circuit 32. The drive circuit 32 includes an inverter circuit that converts DC power supplied from a battery (not shown) into AC power and supplies it to the electric motor 33, thereby driving the electric motor 33. The motor ECU 31 obtains the accelerator pedal's depression depth AD from the speed limit ECU 10. The speed limit ECU 10 can also appropriately correct the depression depth AD obtained from the accelerator pedal sensor 22 and transmit the correction to the motor ECU 31. The motor ECU 31 transmits a torque control signal to the drive circuit 32 based on the depression depth AD obtained from the speed limit ECU 10. The drive circuit 32 adjusts the power supplied to the motor 33 (cycle, duty cycle, etc.) based on the torque control signal received from the motor ECU 21. This control controls the torque generated by the motor 33. The torque generated by the motor 33 is transmitted to the drive wheels via a driving force transmission mechanism (e.g., a drive shaft).

[0042] The brake device 40 applies braking force to the wheels. It includes a brake ECU 41, a hydraulic circuit 42, and a brake caliper 43. The hydraulic circuit 42 includes a reservoir, an oil pump, various valves, a hydraulic pressure sensor, and other components (not shown). The brake caliper 43 is a hydraulic actuator equipped with a hydraulic cylinder and a piston. When oil is supplied to the hydraulic cylinder, the piston is pushed out. A brake pad is mounted on the top of the piston, which pushes against the brake disc. The brake ECU 41 obtains the brake pedal depression depth BD from the speed limit ECU 10. Furthermore, the speed limit ECU 10 can appropriately correct the brake pedal depression depth BD obtained from the brake pedal sensor (not shown) and transmit the information to the brake ECU 41. Based on the depression depth BD obtained from the speed limit ECU 10, the brake ECU 41 transmits a hydraulic control signal to the hydraulic circuit 42. The hydraulic circuit 42 adjusts the hydraulic pressure within the hydraulic cylinder of the brake caliper 43 based on the hydraulic control signal received from the brake ECU 41. In this manner, the braking force on the wheel (brake disc) generated by the brake caliper 43 is controlled.

[0043] (Work)

[0044] The speed limit ECU 10 includes a first speed limit function and a second speed limit function for controlling the drive device 30 and the brake device 40 so that the vehicle's speed vs does not exceed a first speed vs1 and a second speed vs2, respectively. Furthermore, the speed limit ECU 10 includes a first cancellation function and a second cancellation function for disabling the first and second speed limit functions. In other words, the speed limit ECU 10 functions as a first speed limiter that limits speed increases exceeding the first speed vs1. Furthermore, the speed limit ECU 10 functions as a second speed limiter that limits speed increases exceeding the second speed vs2. Furthermore, the speed limit ECU 10 functions as a first cancellation unit that cancels the speed limit imposed by the first speed limiter. Furthermore, the speed limit ECU 10 functions as a second cancellation unit that cancels the speed limit imposed by the second speed limiter.

[0045] (First vehicle speed limiter)

[0046] The first speed limiter controls the drive unit 30 and / or the brake unit 40 so that the vehicle's speed vs does not exceed the first speed vs1 set by the driver using the switch 23. Specifically, the speed limiter ECU 10 predicts (calculates) the vehicle's speed vs from the current time point to a predetermined time later based on data retrieved from the RAM's ring buffer (changes in speed vs within the most recent predetermined time period). If this predicted result exceeds the first speed vs1, the first speed limiter controls the drive unit 30 and / or the brake unit 40 to decelerate the vehicle.

[0047] (Second vehicle speed limiter)

[0048] The second vehicle speed limiter controls the drive device 30 and / or the brake device 40 in such a manner that the speed vs of the vehicle does not exceed the second speed vs2. In addition, in the present embodiment, the first speed vs1 is a value set by the driver using the switch 23, and in contrast, the second speed vs2 is a predetermined value that is set in advance (a value that cannot be changed by a general user). It is known that under normal circumstances, when an electric vehicle is traveling at high speed, the degradation process of the battery is sometimes advanced compared to when it is traveling at low speed. In order to suppress such premature degradation of the battery, a second speed vs2 is specified, and the drive device is controlled in such a manner that the speed vs of the vehicle does not exceed the second speed vs2. In addition, in the following description, it is assumed that the first speed vs1 is set to a lower speed than the second speed vs2.

[0049] (First Cancellation Section)

[0050] As will be described below, the first canceling unit invalidates the first vehicle speed limiting function.

[0051] In a situation where the speed vs of the host vehicle increases and reaches the first speed vs1 and the increase of the speed vs is limited by the first vehicle speed limiting function (i.e., the speed vs = the first speed vs1), the first cancellation unit disables the first vehicle speed limiting function when the following first accelerator pedal condition A1 is satisfied (see Figure 2 ).

[0052] (A1) The duration of a state in which the depression depth AD of the accelerator pedal exceeds the first depth AD1 exceeds the first time T1.

[0053] Here, the first depth AD1 is preset so that the speed vs is higher than the first speed when the accelerator pedal is depressed at the first depth AD1. When the first vehicle speed limit function is disabled due to the satisfaction of the first accelerator condition A1, the speed vs can be higher than the first speed vs1.

[0054] (Second Cancellation Section)

[0055] As will be described below, the second canceling unit invalidates the second vehicle speed limit function.

[0056] In a situation where the speed vs of the vehicle increases and reaches the second speed vs2, and the increase in the speed vs of the vehicle is limited by the second speed limit function (i.e., the speed vs = the second speed vs2), the second cancellation unit disables the second speed limit function when the second accelerator pedal condition A2 described below is met.

[0057] (A2) The duration of the state in which the depression depth AD of the accelerator pedal exceeds the second depth AD2 (> AD1) exceeds the second time T2.

[0058] Here, the second depth AD2 is preset so that when the accelerator pedal is depressed at the second depth AD2, the speed vs is higher than the second speed vs. When the second vehicle speed limit function is disabled due to the satisfaction of the second accelerator condition A2, the speed vs can be made higher than the second speed vs2.

[0059] When disabling the first and second speed limit functions in different scenarios, there is no problem as long as the first and second speed limit functions can be independently disabled when the first and second accelerator pedal conditions are met. On the other hand, in situations (special situations), such as when an evasive maneuver is required, such as avoiding an obstacle, it is preferable to be able to quickly disable the first and second speed limit functions. Furthermore, in such special situations, it is cumbersome for the driver to ensure that different conditions (the first and second accelerator pedal conditions) are met in order to disable each speed limit function (the first and second speed limit functions), and this may result in the driver failing to achieve the purpose of the special situation (e.g., avoiding an obstacle). Furthermore, since at least the second time T2 must be waited for the second accelerator pedal condition A2 to be met, disabling the second speed limit function takes time.

[0060] In contrast, in this embodiment, at time point t2 when the speed vs reaches the second speed vs2, if at least one of the following conditions X1 and X2 is met and condition Y is met, the second cancellation unit invalidates the second vehicle speed limit function (forced cancellation function) even if the second accelerator pedal condition A2 is not met.

[0061] (X1) The time t taken from the time point t1 when the first vehicle speed limit function is disabled until the speed vs of the host vehicle reaches the second speed vs2 is smaller than the threshold value tth.

[0062] (X2) The difference between the first speed vs1 and the second speed vs2 is smaller than the threshold value vsth.

[0063] (Y) From time point t1 to time point t2, the first accelerator pedal condition A1 continues to be satisfied.

[0064] According to this forced cancellation function, when the above-mentioned condition X1 or X2 is satisfied and the condition Y is satisfied, the second vehicle speed limit function is quickly disabled at time t2 (time when the speed vs reaches the second speed vs2).

[0065] The function of disabling the second vehicle speed limit function when conditions X1 and Y are satisfied corresponds to the first forced cancellation function of the present invention. The function of disabling the second vehicle speed limit function when conditions X2 and Y are satisfied corresponds to the second forced cancellation function of the present invention.

[0066] Furthermore, after disabling the first vehicle speed limit function, the first canceling unit enables the first vehicle speed limit function when the speed vs decreases and becomes lower than a threshold value vsth1 that is lower than the first speed vs1. Furthermore, after disabling the second vehicle speed limit function, the second canceling unit enables the second vehicle speed limit function when the speed vs decreases and becomes lower than a threshold value vsth2 that is lower than the second speed vs2.

[0067] Next, refer to Figures 3 to 6 , the operation (programs P1, P2, P3, and P4 for respectively implementing the first speed limit function, the second speed limit function, the first cancellation function, and the second cancellation function) of the above-mentioned speed limit ECU 10 (hereinafter referred to as "CPU") will be described. When the ignition switch of the present vehicle is in the on state, the CPU executes programs P1 to P4 at a predetermined cycle. In addition, in programs P1 to P4, a mark SL1 and a mark SL2 are used. When the first speed limit function is being validated, the mark SL1 is "on". When the first speed limit function is being invalidated, the mark SL1 is "off". When the second speed limit function is being validated, the mark SL2 is "on". When the second speed limit function is being invalidated, the mark SL2 is "off". At the time point when the ignition switch of the present vehicle is turned off, the marks SL1 and SL2 are initialized to "on".

[0068] (Program P1)

[0069] The CPU starts program P1 from step 100 and proceeds to step 101 .

[0070] When the process proceeds to step 101, the CPU determines whether flag SL1 is "ON." If flag SL1 is "ON" (101: YES), the CPU proceeds to step 102. On the other hand, if flag SL1 is "OFF" (101: NO), the CPU proceeds to step 103 and terminates execution of program P1.

[0071] When the process proceeds to step 102 , the CPU controls the driving device 30 and the braking device 40 so that the speed vs is maintained at or below the first speed vs1 .

[0072] (Program P2)

[0073] The CPU starts the program P2 from step 200 and proceeds to step 201 .

[0074] When the process proceeds to step 201, the CPU determines whether flag SL2 is "ON." If flag SL2 is "ON" (201: YES), the CPU proceeds to step 202. On the other hand, if flag SL2 is "OFF" (201: NO), the CPU proceeds to step 203 and terminates execution of program P2.

[0075] When the process proceeds to step 202 , the CPU controls the driving device 30 and the braking device 40 so that the speed vs is maintained at or below the second speed vs2 .

[0076] (Program P3)

[0077] The CPU starts the program P3 from step 300 and proceeds to step 301 .

[0078] When proceeding to step 301 , the CPU determines whether flag SL1 is “ON.” If flag SL1 is “ON” ( 301 : YES), the CPU proceeds to step 302 . On the other hand, if flag SL1 is “OFF” ( 301 : NO), the CPU proceeds to step 306 .

[0079] Upon proceeding to step 302, the CPU determines whether the speed vs matches the first speed vs1. Specifically, the CPU determines whether the speed vs has increased and reached the first speed vs1, and whether the first vehicle speed limit function has limited the increase in speed vs above the first speed vs1. If the speed vs matches the first speed vs1 (302: Yes), the CPU proceeds to step 303. On the other hand, if the speed vs is less than the first speed vs1 (302: No), the CPU proceeds to step 308 and terminates execution of program P3.

[0080] When the process proceeds to step 303 , the CPU determines whether condition A1 is satisfied. If condition A1 is satisfied ( 303 : Yes), the CPU proceeds to step 304 . On the other hand, if condition A1 is not satisfied ( 303 : No), the CPU proceeds to step 308 .

[0081] When the process proceeds to step 304 , the CPU sets the flag SL1 to “off.” That is, the CPU disables the first vehicle speed limit function. Then, the CPU proceeds to step 305 .

[0082] When the process proceeds to step 305 , the CPU initializes the measured time t (output value) of the timer to “0” and starts time measurement (measuring the elapsed time from the time when the first vehicle speed limit function is disabled).

[0083] Furthermore, when proceeding from step 301 to step 306, the CPU determines whether the speed vs is less than a threshold value vsth1, which is lower than the first speed vs1. If the speed vs is less than the threshold value vsth1 (306: Yes), the CPU proceeds to step 307. On the other hand, if the speed vs is greater than the threshold value vsth1 (306: No), the CPU proceeds to step 308.

[0084] When proceeding to step 307 , the CPU sets the flag SL1 to “ON.” Then, the CPU proceeds to step 308 .

[0085] (Program P4)

[0086] The CPU starts program P4 from step 400 and proceeds to step 401 .

[0087] When the process proceeds to step 401 , the CPU determines whether flag SL2 is “ON.” If flag SL2 is “ON” ( 401 : YES), the CPU proceeds to step 402 . On the other hand, if flag SL2 is “OFF” ( 401 : NO), the CPU proceeds to step 408 .

[0088] Upon proceeding to step 402, the CPU determines whether the speed vs matches the second speed vs2. Specifically, the CPU determines whether the speed vs has increased and reached the second speed vs2, and whether the second speed limit function has limited the increase in speed vs above the second speed vs2. If the speed vs matches the second speed vs2 (402: Yes), the CPU proceeds to step 403. On the other hand, if the speed vs is less than the second speed vs2 (402: No), the CPU proceeds to step 410 and terminates execution of program P4.

[0089] When the process proceeds to step 403 , the CPU determines whether condition A2 is satisfied. If condition A2 is satisfied ( 403 : Yes), the CPU proceeds to step 404 . On the other hand, if condition A2 is not satisfied ( 403 : No), the CPU proceeds to step 405 .

[0090] When the process proceeds to step 404 , the CPU sets the flag SL2 to “off.” That is, the CPU disables the second vehicle speed limit function. Then, the CPU proceeds to step 410 .

[0091] Furthermore, when proceeding from step 403 to step 405, the CPU determines whether the time t measured by the timer (the time elapsed from time t1 when the first speed limit function was disabled) is less than a threshold value tth. If the measured time t is less than the threshold value tth (405: Yes), the CPU proceeds to step 407. On the other hand, if the measured time t is greater than or equal to the threshold value tth (405: No), the CPU proceeds to step 406.

[0092] When the process proceeds to step 406, the CPU determines whether the difference between the second speed vs2 and the first speed vs1 is less than a threshold value vsth. If the difference between the second speed vs2 and the first speed vs1 is less than the threshold value vsth (406: Yes), the CPU proceeds to step 407. On the other hand, if the difference between the second speed vs2 and the first speed vs1 is greater than the threshold value vsth (406: No), the CPU proceeds to step 410.

[0093] When the process proceeds to step 407, the CPU determines whether condition A1 has continued to hold since time t1, when the first speed limit function was disabled, based on the pedaling depth AD stored in the RAM (ring buffer). If condition A1 has continued to hold since time t1 (407: Yes), the CPU proceeds to step 404. On the other hand, if there is a period of time after the first speed limit function was disabled during which condition A1 did not hold (407: No), the CPU proceeds to step 410.

[0094] Furthermore, when proceeding from step 401 to step 408, the CPU determines whether the speed vs is less than a threshold value vsth2 that is lower than the second speed vs2. If the speed vs is less than the threshold value vsth2 (408: Yes), the CPU proceeds to step 409. On the other hand, if the speed vs is greater than the threshold value vsth2 (408: No), the CPU proceeds to step 410.

[0095] When proceeding to step 409 , the CPU sets the flag SL2 to “ON.” Then, the CPU proceeds to step 410 .

[0096] (Effect)

[0097] A situation in which the vehicle is accelerated so that the speed vs reaches the second speed vs2 from the first speed vs1 in a relatively short time (less than a threshold value tth) after the first speed limit function is disabled can be considered a highly urgent situation (a special situation requiring rapid vehicle acceleration). In this embodiment, if the measured time t is less than the threshold value tth and condition A1 is satisfied at the second time point t2, the second speed limit function is disabled by the first forced cancellation function, even if condition A2 is not satisfied. Furthermore, in special situations in which the difference between the first speed vs1 and the second speed vs2 is small, the necessity for providing two speed limit functions (the first speed limit function and the second speed limit function) is less. Therefore, in this embodiment, if the difference between the first speed vs1 and the second speed vs2 is less than the threshold value vsth, and condition A1 continues to be satisfied from the first time point t1 to the second time point t2, the second speed limit function is disabled by the second forced cancellation function. That is, in the above-described special situation, after the driver has depressed the accelerator pedal to a depth greater than the first depth AD1 to disable the first vehicle speed limit function, it is not necessary to depress the accelerator pedal to a depth greater than the second depth AD2, which is deeper than the first depth AD1, in order to disable the second vehicle speed limit function. As described above, according to this embodiment, in special situations, the driver can disable the second vehicle speed limit function more easily than in normal situations.

[0098] The present invention is not limited to the above-described embodiment, and various modifications can be adopted within the scope of the present invention as described below.

[0099] <Change Example 1>

[0100] Although the second speed vs2 is predetermined in the above embodiment, the driver may also be able to set (change) the second speed vs2. In addition, the second speed vs2 is not limited to a speed limit value for suppressing battery degradation, but may also be a speed limit value for achieving other purposes.

[0101] <Change Example 2>

[0102] In the above embodiment, condition Y is satisfied when "the first accelerator pedal condition A1 continues to be satisfied during the period from time t1 to time t2." Alternatively, condition Y may be satisfied when "the first accelerator pedal condition A1 is satisfied at time t2." In other words, in this case, even if there is a period from time t1 to time t2 where the depression depth AD is less than the first depth AD1, condition Y is satisfied as long as the first accelerator pedal condition A1 is finally satisfied at time t2.

[0103] <Change Example 3>

[0104] The vehicle speed limit ECU 10 may include only one of the first forced cancellation function and the second forced cancellation function.

[0105] <Change Example 4>

[0106] Either or both of the first accelerator pedal condition A1 and the second accelerator pedal condition A2 may be changed as follows.

[0107] (A1) The increasing rate (% / second) of the depression depth AD of the accelerator pedal exceeds the first increasing rate.

[0108] (A2) The rate of increase (% / second) of the depression depth AD of the accelerator pedal exceeds the second rate of increase.

Claims

1. A vehicle speed limiter comprising: an operating portion sensor that detects an operating mode of an operating portion operated by a driver when accelerating the vehicle; A speed sensor, which detects the speed of the vehicle; A control device having a first vehicle speed limiting function, a first cancellation function, a second vehicle speed limiting function, and a second cancellation function, wherein: The first speed limiting function is a function of controlling one or both of the driving device and the braking device of the vehicle so that the speed does not exceed a first speed. The first cancellation function is a function of invalidating the first speed limiting function when a first operating unit condition related to the operation of the operating unit is satisfied under a condition that the speed of the vehicle coincides with the first speed. The second speed limiting function is a function of controlling one or both of the driving device and the braking device of the vehicle so that the speed of the vehicle does not exceed a second speed that is higher than the first speed. The second cancellation function is a function of invalidating the second speed limiting function when a second operating unit condition related to the operation of the operating unit is satisfied under a condition that the speed of the vehicle coincides with the second speed. In the vehicle speed limiter, the control device includes a first forced cancellation function and a second forced cancellation function. The first forced cancellation function is a function for forcibly disabling the second speed limit function if the time elapsed from a first time point at which the first speed limit function is disabled by the first cancellation function to a second time point at which the speed of the host vehicle reaches the second speed is less than a predetermined threshold value and the first operating portion condition is satisfied at the second time point. The second forced cancellation function is a function for forcibly disabling the second vehicle speed limit function if the first operating portion condition is satisfied at the second time point after the first vehicle speed limit function is disabled by the first cancellation function, when the difference between the first speed and the second speed is smaller than a predetermined threshold value.

2. The vehicle speed limiter according to claim 1, wherein: The first forced cancellation function is a function forcibly disabling the second vehicle speed limit function when the elapsed time from the first time point to the second time point is less than a predetermined threshold and the first operating portion condition continues to be satisfied from the first time point to the second time point.

3. The vehicle speed limiter according to claim 1 or claim 2, wherein: The second forced cancellation function is a function forcibly disabling the second vehicle speed limit function when the difference between the first speed and the second speed is smaller than a predetermined threshold and when the first operating portion condition continues to be satisfied from the first time point to the second time point.

4. A vehicle speed limiting method, comprising: a step of detecting an operation mode of an operating portion operated by a driver when accelerating the vehicle; The step of detecting the speed of the vehicle; A control step for realizing a first vehicle speed limiting function, a first cancellation function, a second vehicle speed limiting function, and a second cancellation function, wherein the first vehicle speed limiting function is a function for controlling one or both of a driving device and a braking device of the vehicle in such a manner that the speed does not exceed a first speed; the first cancellation function is a function for invalidating the first vehicle speed limiting function when a first operating unit condition related to the operation of the operating unit is satisfied under a condition that the speed of the vehicle coincides with the first speed; the second speed limiting function is a function for controlling one or both of a driving device and a braking device of the vehicle in such a manner that the speed of the vehicle does not exceed a second speed which is higher than the first speed; and the second cancellation function is a function for invalidating the second vehicle speed limiting function when a second operating unit condition related to the operation of the operating unit is satisfied under a condition that the speed of the vehicle coincides with the second speed. In the vehicle speed limiting method, the control step includes a step of implementing at least one of a first forced cancellation function and a second forced cancellation function. The first forced cancellation function is a function for forcibly disabling the second speed limit function if the time elapsed from a first time point at which the first speed limit function is disabled by the first cancellation function to a second time point at which the speed of the host vehicle reaches the second speed is less than a predetermined threshold value and the first operating portion condition is satisfied at the second time point. The second forced cancellation function is a function for forcibly disabling the second vehicle speed limit function if the first operating unit condition is satisfied at the second time point after the first vehicle speed limit function is disabled by the first cancellation function when the difference between the first speed and the second speed is less than a predetermined threshold value.

5. A storage medium containing a speed limit program, wherein the speed limit program causes a computer of a vehicle to execute the following steps, namely: a step of detecting an operation mode of an operating portion operated by a driver when accelerating the vehicle; The step of detecting the speed of the vehicle; The control steps for realizing the first speed limiting function, the first cancellation function, the second speed limiting function and the second cancellation function are as follows: The first speed limiting function is a function of controlling one or both of the driving device and the braking device of the vehicle so that the speed does not exceed a first speed. The first cancellation function is a function of invalidating the first speed limiting function when a first operating unit condition related to the operation of the operating unit is satisfied under a condition that the speed of the vehicle coincides with the first speed. The second speed limiting function is a function of controlling one or both of the driving device and the braking device of the vehicle so that the speed of the vehicle does not exceed a second speed that is higher than the first speed. The second cancellation function is a function of invalidating the second speed limiting function when a second operating unit condition related to the operation of the operating unit is satisfied under a condition that the speed of the vehicle coincides with the second speed. The control step includes a step of implementing at least one of a first forced cancellation function and a second forced cancellation function. The first forced cancellation function is a function for forcibly disabling the second speed limit function if the time elapsed from a first time point at which the first speed limit function is disabled by the first cancellation function to a second time point at which the speed of the host vehicle reaches the second speed is less than a predetermined threshold value and the first operating portion condition is satisfied at the second time point. The second forced cancellation function is a function for forcibly disabling the second vehicle speed limit function if the first operating portion condition is satisfied at the second time point after the first vehicle speed limit function is disabled by the first cancellation function, when the difference between the first speed and the second speed is smaller than a predetermined threshold value.

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