Speed limiting device and speed limiting method for electric vehicle

Abstract

To provide a speed regulating device and a speed regulating method for an electric vehicle capable of performing proper speed regulation by using a device which can be retrofitted to an existing electric vehicle.SOLUTION: When a vehicle speed obtained from an actual speed signal exceeds a regulation speed, an interrupt regulation signal is outputted from a processor unit 2 to turn on a shunt circuit 3, and a circuit from an accelerator position sensor 14S is partially leaked from the shunt circuit 3 to reduce motor driving power from a power control unit 13 originally mounted on a vehicle V, thereby regulating the vehicle speed to a predetermined regulation speed regardless of an operation state of an accelerator assembly 14 including the accelerator position sensor 14S.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a speed control device and a speed control method that can be applied to electric vehicles that are often used, for example, in food delivery services and are subject to low legal speed limits. [Background technology]

[0002] For example, food delivery services that deliver pre-cooked food to your door are becoming more common, and in addition to conventional engine-driven vehicles, the number of electrically powered vehicles used for these services is on the rise. Most of these vehicles are two- or three-wheeled, low-speed vehicles that are legally classified as Type 1 motorized bicycles and are limited to a legal speed of 30 km / h or less. However, in consideration of practical performance such as avoiding danger while driving, the actual maximum speed is set at 55 km / h to 60 km / h. For this reason, when we look at the actual driving conditions at delivery sites, due to customer order requests, delivery staff are often unable to maintain full compliance with the legal speed limit, and in extreme cases, they are forced to drive at nearly 60 km / h, the limit of their vehicle's performance. Naturally, driving at speeds significantly exceeding the legal limit often damages cooked food and other products during delivery, and is also illegal in the first place, posing a significant risk of causing accidents. Incidentally, devices such as those in the following patent documents have been proposed to remove the speed limit imposed at the time of shipment from the manufacturer in order to modify vehicles into racing vehicles for use off public roads. However, speed limiting devices, particularly for electric vehicles, that set the speed below the maximum speed imposed at the time of manufacture have not yet become widespread. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-53053 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention was made in consideration of this background, and its technical objective was to develop a speed control device and speed control method for electric vehicles that can appropriately control speed using a device that can be retrofitted to existing electrically driven vehicles. [Means for solving the problem]

[0005] First, the speed regulation device for electric vehicles described in claim 1 is a speed regulation device for electric vehicles that can be applied to low legal speed electric vehicles with a performance in which the actual maximum speed exceeds the legal speed limit, and this device comprises a processor unit whose input signal is the actual speed signal of the vehicle and whose output signal is an interrupt regulation signal to the accelerator position sensor of the vehicle, and a shunt circuit that is installed in the output circuit of the original accelerator position sensor, and this shunt circuit is installed in two systems corresponding to the output circuits of the two systems of the original accelerator position sensor, When the vehicle speed obtained from the actual speed signal exceeds the regulated speed, the processor unit outputs an interrupt regulation signal intermittently in the range of 1 to 5 seconds, turning on the shunt circuit, causing the output circuit from the accelerator position sensor to be partially leaked from the shunt circuit, reducing the motor drive power from the power control unit originally installed in the vehicle, and regulating the vehicle speed to the specified regulated speed regardless of the operating status of the accelerator assembly including the accelerator position sensor.

[0006] The speed regulation device for an electric vehicle according to claim 2 is characterized in that the signal output from the processor unit to the shunt circuit is output intermittently within a range of 1 to 5 seconds.

[0007] In addition to the requirements of claim 1 or 2, the speed control device for an electric vehicle described in claim 3 is characterized in that, in situations where the running resistance of the vehicle is reduced, the signal output to the shunt circuit is continued for a certain period of time to avoid the activation of the fail-safe function due to the signal output from the processor unit to the shunt circuit being output intermittently and frequently.

[0008] Furthermore, the speed control device for an electric vehicle described in claim 4 has, in addition to the requirements described in claim 1, The speed limiting device is characterized in that it has a dedicated built-in battery or is powered by a battery originally installed in the vehicle.

[0009] The speed restriction method for electric vehicles described in claim 5 is a speed restriction method applicable to low legal speed electric vehicles with a performance in which the actual maximum speed exceeds the legal speed limit, and this speed restriction method is carried out using a restriction device unit, and this restriction device unit comprises a processor unit whose input signal is the actual speed signal of the vehicle and whose output signal is an interrupt restriction signal to the accelerator position sensor of the vehicle, and a shunt circuit which is installed in the output circuit of the original accelerator position sensor, and this shunt circuit is installed in two systems corresponding to the output circuits of the two systems of the original accelerator position sensor, When the vehicle speed obtained from the actual speed signal exceeds the regulated speed, an interrupt regulation signal is output from the processor unit to turn on the shunt circuit, causing the output circuit from the accelerator position sensor to be partially leaked from the shunt circuit, reducing the motor drive power from the power control unit originally installed in the vehicle, and regulating the vehicle speed to the specified regulated speed regardless of the operating status of the accelerator assembly including the accelerator position sensor.

[0010] Furthermore, the method for regulating the speed of an electric vehicle described in claim 6 is characterized in that, in addition to the requirements described in claim 5, the signal output from the processor unit to the shunt circuit is output intermittently in the range of 1 to 5 seconds.

[0011] In addition to the requirements of claim 5, the method for regulating the speed of an electric vehicle described in claim 7 is characterized in that, in a situation where the running resistance of the vehicle is reduced, the signal output to the shunt circuit is continued for a certain period of time to avoid the activation of the fail-safe function due to the signal output from the processor unit to the shunt circuit being output intermittently and frequently. [Effects of the Invention]

[0012] According to the invention of claim 1 or 5, the system comprises a processor unit whose input signal is an actual vehicle speed signal and whose output signal is an interruption restriction signal to the accelerator position sensor of the vehicle, and a shunt circuit which is installed in the output circuit of the original accelerator position sensor, and two systems of the shunt circuit are provided corresponding to the output circuits of the two systems of the original accelerator position sensor, When the vehicle speed obtained from the actual speed signal exceeds the regulated speed, an interrupt regulation signal is output from the processor unit, the shunt circuit is turned on, the output circuit from the accelerator position sensor is put into a partial leakage state from the shunt circuit, and the motor drive power from the power control unit originally installed in the vehicle is reduced, so that the vehicle speed can be regulated to the specified regulated speed regardless of the operating status of the accelerator assembly including the accelerator position sensor.

[0013] According to the invention described in claim 2 or 6, the signal output from the processor unit to the shunt circuit is output intermittently in the range of 1 to 5 seconds, so that when the regulated speed is exceeded, a sudden deceleration state is avoided and a gradual deceleration is performed, thereby ensuring safe operation.

[0014] According to the invention described in claim 3 or 7, in order to avoid the activation of the fail-safe function due to the signal output from the processor unit to the shunt circuit being output intermittently and frequently when the vehicle's running resistance is reduced, the signal output to the shunt circuit is continued for a certain period of time, so that erroneous information is not sent to the control circuit installed on the original vehicle, and stable running conditions are ensured.

[0015] According to the invention described in claim 4, the speed limiting device is either equipped with a dedicated battery or is powered by a battery originally installed in the vehicle, so there is no need to separately install a dedicated power supply for the processor unit, especially if the original battery installed in the vehicle is used. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a perspective view of a motorcycle according to an embodiment and a functional block diagram of a control system thereof; [Figure 2] 10A and 10B are a perspective view and a functional block diagram of a control system of a motorcycle according to another embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0017] The present invention is embodied in the following examples, and also includes various methods that can be improved within the scope of the technical concept. [Example]

[0018] The present invention will be specifically described below based on the illustrated embodiments. First, we will explain the speed regulation device 1 used in implementing the speed regulation method for electric vehicles according to the present invention. This device can be applied to, for example, a typical small motorcycle or a low-speed electric vehicle (hereinafter sometimes referred to as vehicle V) classified as a Type 1 motorized bicycle with one front wheel and two rear wheels, as shown in Figure 1, which is often used for home delivery and the like. Note that low-speed electric vehicles are not limited to Type 1 motorized bicycles with a speed limit of 30 km / h or less, but also include Type 2 motorized bicycles with a speed limit of 60 km / h or less, as they are restricted from traveling on expressways.

[0019] Here, an outline of a primary drive unit 10 in a general electrically driven vehicle V is shown in the block diagram of FIG. The main drive device 10 is generally configured to include a gearbox 11 housing a drive motor M, a power control unit 13 that controls the power supply to the drive motor M, and an accelerator assembly 14 that allows the driver to control the speed. A drive battery B of several tens of volts, for example, is used as the drive power source for this drive. First, the gearbox 11 is essentially a housing made of, for example, die-cast material that supports the drive wheels W and houses the drive motor M, and is equipped with a speed sensor 12 that is provided at an appropriate position in the power transmission train on the drive wheels W and the accelerator assembly 14 connected thereto. Incidentally, a separate 12V battery B1 is provided as a power source for safety parts including lights such as headlights, taillights, and turn signals, as well as a horn.

[0020] The drive motor M may be, for example, an AC synchronous motor, and in this case, is driven by an AC power supply that has been converted and boosted from the DC drive battery B. The speed sensor 12 outputs an actual speed signal representing the rotation state as a pulse signal by combining a toothed rotor and a proximity sensor, and this actual speed signal is input to a power control unit 13 and also to the speed regulation device 1 used in carrying out the present invention.

[0021] Next, an overview of the power control unit 13 will be given. This unit receives an actual speed signal from the speed sensor 12 and an accelerator opening signal from the accelerator assembly 14, and outputs a command signal for a specified power output. Incidentally, the control circuitry for outputting this command signal is driven not by the high-output drive battery B, but by a separate, dedicated low-voltage battery B1. Based on this command signal, AC output powered by the drive battery B is supplied to the drive motor M.

[0022] The accelerator assembly 14 is equipped with two accelerator position sensors 14S1 and 14S2, each consisting of a variable resistor, connected in parallel. The two accelerator position sensors 14S1 and 14S2 are provided to provide what are known as fail-proof or fail-safe measures for emergency situations. Specifically, one of the accelerator position sensors, 14S2, is compared with an appropriate accelerator rotation determined from an actual speed signal and other driving conditions, such as the running resistance of an uphill slope. If the difference between the output of the other accelerator position sensor, 14S1, becomes excessive, an abnormality is detected and the vehicle is stopped, providing a so-called fail-safe measure.

[0023] The speed control device 1 used to implement the method of the present invention for such a vehicle V can be optionally installed and has the following configuration. The speed regulation device 1 comprises a processor unit 2, a shunt circuit 3, and a power supply inverter 4. The processor unit 2 receives as input an actual speed signal from an originally installed speed sensor 12. When this actual speed signal is received, the signal value (actual speed) is first compared with a speed limit set lower than the original maximum speed of the vehicle V. If the actual speed is below the speed limit, the accelerator opening of the accelerator assembly 14 of the vehicle V is allowed as is. On the other hand, if the actual speed is above the speed limit, a signal is output to reduce the speed to the speed limit regardless of the accelerator opening. For this purpose, parallel accelerator control boards 21 and 22 are provided within the processor unit 2, as well as a speed setting board 24 and a hold time setting board 25.

[0024] As shown in the figure, outputs from accelerator control boards 21, 22 are input to shunt circuit 3, and shunt control lines 3L1, 3L2 are connected to shunt control units 3U1, 3U2, respectively. In these shunt control units 3U1, 3U2, a resistance element 3R and a switching element 3S are connected in series, and the resistance element 3R side is connected in parallel to output lines 14L1, 14L2 of accelerator position sensors 14S1, 14S2 in accelerator assembly 14 originally installed in vehicle V, respectively.

[0025] The speed control device 1 shown in FIGS. 1 and 2 does not use the battery B or the battery B1 as a drive source for the vehicle V, but instead has a separate dedicated battery B2 built in. This battery B2 receives power from the battery B1 installed in the vehicle V or from the battery B1. Of course, as shown in FIG. 2, when power is supplied from the high-voltage battery B used as a drive source, an inverter 4, enclosed by a chain line in the figure, may be installed to convert the power to a low voltage for driving the processor unit 2. The inclusion of the battery B2 makes it possible to maintain the function of the speed control device 1 at all times even in the unlikely event that the on-board battery B or battery B1 runs out of power and the power supply is cut off. Therefore, in addition to a rechargeable secondary battery, a capacitor or the like may also be used for the battery B2. Although not shown, it is also possible to have a configuration in which the dedicated battery B2 is not provided within the speed control device 1. In this case, the + and - (earth side) wiring coming out of the battery B2 in Figures 1 and 2 is wired so as to connect to the + and - wiring coming out of the battery B1.

[0026] The speed control device used to implement the present invention has the above-described configuration, and operates as follows to perform speed control according to the method of the present invention. 1) Installation of speed limiter 1 First, the unitized speed limiter 1 is installed in an available space on the vehicle V. The circuit wiring work for the vehicle V involves connecting one end of the resistance element 3R in the shunt control units 3U1 and 3U2 in parallel to the output lines 14L1 and 14L2 from the accelerator position sensors 14S1 and 14S2 in the originally installed accelerator assembly 14 in an interrupted manner. On the other hand, the power supply side is connected to the original battery B or battery B1 so that it can supply power, whether the speed limiter is equipped with a dedicated battery or not. In this case, when connecting to the high-voltage battery B for driving, the connection is made via the power supply inverter 4.

[0027] 2) Driving in compliance with the law For example, if the legal speed limit for a Class 1 motorized bicycle is 30 km / h, and the speed limit set by the speed limiter 1 of the present invention is, for example, 40 km / h, as long as the bicycle is traveling in accordance with the law, the signal input to the speed input board 23 in the processor unit 1 will be equal to or less than the legal speed set by the speed setting board 24. Therefore, no particular control signal is output from the accelerator control boards 21 and 22.

[0028] 3) When driving at high speed On the other hand, if the driver fully operates the accelerator pedal, the vehicle's motion inertia and running resistance will decrease, causing the vehicle to exceed the speed limit by a large margin. For example, conditions such as downhill driving or a tailwind can cause the vehicle to exceed the speed limit. In such a case, when the actual speed signal from the original speed sensor 12 is input to the speed input board 23, the processor unit 2 compares the actual speed with the speed limit and determines whether the speed limit has been exceeded. Based on this determination, the accelerator control boards 21 and 22 output a command signal to the shunt circuit via the shunt control lines 3L1 and 3L2, turning on the switching element 3S in the shunt control units 3U1 and 3U2. As a result, the resistance of resistor 3R is applied to both of output lines 14L1, 14L2 of accelerator position commands input from original accelerator position sensors 14S1, 14S2 to original power control unit 13, causing the accelerator to appear to be operating in an intermediate state, such as halfway up to full throttle, regardless of the apparent accelerator opening. As a result, signal processing within power control unit 13 reduces the power supplied to drive motor M, and the vehicle speed is returned to the regulated speed.

[0029] 4) Deceleration buffer However, if such a deceleration operation is performed regardless of the driver's intention, the deceleration will be sudden, causing confusion for the driver and impairing the running stability of the vehicle V itself. Therefore, in the present invention, the actuation signal sent to the switching element 3S in the branch control units 3U1, 3U2 that brings about the deceleration state is not simply continued, but is set at regular intervals by the hold time setting board 25. For example, smooth deceleration is achieved by turning the switching element 3S on and off every 1 to 2 seconds.

[0030] 5) Reduction of running resistance Furthermore, during the actual driving state, road conditions and other factors often cause changes in running resistance. When conditions that reduce running resistance occur, such as when driving downhill or in an extreme tailwind, the following problem arises. For example, when driving downhill, if the speed limit is exceeded, a speed limiting signal is sent to the switching element 3S in the shunt control units 3U1 and 3U2, restoring the vehicle to the speed limit. However, if the vehicle returns to the speed limit and then moves downhill, the speed limiting signal is frequently and intermittently transmitted through the shunt circuit. In this state, the input signal from the accelerator position sensor 14S to the power control unit 13 also changes rapidly, which ultimately diagnoses a malfunction in the power control unit 13 and activates the so-called fail-safe function, which disables driving. Therefore, by maintaining the speed limiting state for a certain period of time, e.g., 1 to 5 seconds, during low-load conditions such as on a slope, the speed limiting signal from the accelerator position sensor to the power control unit 13 changes gradually. [Explanation of symbols]

[0031] B Drive battery B1 Battery (for auxiliary equipment) B2 Battery (for speed control device only) M drive motor V Vehicle W drive wheels 1 Speed ​​regulation device 10. Prime Drive 11 Gearbox 12 Speed ​​sensor 13 (Original) Power Control Unit 14 Axle assembly 14S Accelerator position sensor 14S1 Accelerator position sensor 14S2 Accelerator position sensor 14L1 output line 14L2 output line 2 processor units 21 Accelerator control board 22 Accelerator control board 23 Speed ​​Input Board 24 Speed ​​setting board 25 Retention time setting board 3 Shunt circuit 3L1 Shunt control line 3L2 shunt control line 3R resistor element 3S switching element 3U1 Shunt Control Unit 3U2 Shunt Control Unit 4 Power supply inverter

Claims

1. A speed control device for electric vehicles that can be applied to low legal speed electric vehicles with a performance in which the actual maximum speed exceeds the legal speed limit, the device comprising: a processor unit whose input signal is the actual speed signal of the vehicle and whose output signal is an interruption control signal to the accelerator position sensor of the vehicle; and a shunt circuit that is installed in the output circuit of the original accelerator position sensor; and two systems of the shunt circuit are provided corresponding to the output circuits of the two systems of the original accelerator position sensor. When the vehicle speed obtained from the actual speed signal exceeds the regulated speed, an interrupt regulation signal is output from the processor unit to turn on the shunt circuit, causing the output circuit from the accelerator position sensor to be in a partial leak state from the shunt circuit, reducing the motor drive power from the power control unit originally installed in the vehicle, and regulating the vehicle speed to a predetermined regulated speed regardless of the operating status of the accelerator assembly including the accelerator position sensor.

2. 2. The speed limiting device for an electric vehicle according to claim 1, wherein the signal output from said processor unit to said shunt circuit is output intermittently within a range of 1 to 5 seconds.

3. 2. The speed control device for a low-speed electric vehicle according to claim 1, wherein the signal output from the processor unit to the shunt circuit is continued for a certain period of time to avoid activation of the fail-safe function due to frequent intermittent signal output from the processor unit to the shunt circuit when the running resistance of the vehicle is reduced.

4. 2. The speed limiting device for an electric vehicle according to claim 1, wherein the speed limiting device is powered by a dedicated battery built in or by a battery originally installed in the vehicle.

5. A speed restriction method applicable to a low legal speed electric vehicle having a performance in which the actual maximum speed exceeds the legal speed limit, said speed restriction method being carried out using a restriction device unit, said restriction device unit comprising a processor unit whose input signal is an actual speed signal of the vehicle and whose output signal is an interrupt restriction signal to an accelerator position sensor of the vehicle, and a shunt circuit which is installed in the output circuit of the original accelerator position sensor, and said shunt circuit is provided in two systems corresponding to the output circuits of the two systems of the original accelerator position sensor, A speed regulation method for an electric vehicle, characterized in that when the vehicle speed obtained from the actual speed signal exceeds the regulated speed, an interrupt regulation signal is output from the processor unit to turn on the shunt circuit, causing the output circuit from the accelerator position sensor to be in a partial leak state from the shunt circuit, reducing the motor drive power from the power control unit originally installed in the vehicle, and regulating the vehicle speed to a predetermined regulated speed regardless of the operating status of the accelerator assembly including the accelerator position sensor.

6. 6. The method for regulating the speed of an electric vehicle according to claim 5, wherein the signal output from the processor unit to the shunt circuit is output intermittently within a range of 1 to 5 seconds.

7. 6. The method for regulating the speed of an electric vehicle according to claim 5, wherein the signal output from the processor unit to the shunt circuit is continued for a certain period of time to avoid activation of the fail-safe function due to frequent intermittent signal output from the processor unit to the shunt circuit under conditions where the running resistance of the vehicle is reduced.

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