Drive control device, vehicle

Abstract

The drive control device and the vehicle are configured such that, when the throttle (110) is in a fully closed state, when the vehicle (1) is traveling at a predetermined first speed range (V1), a torque (T1) in a first rotational direction (R1) for moving the vehicle (1) forward is imparted to the drive wheels (4a, 4b) through a power unit (P); and when the vehicle (1) is traveling at a second speed range (V2) set at a higher speed than the first speed range (V1), a torque (T2) in a second rotational direction (R2) opposite to the first rotational direction (R1) is imparted to the drive wheels (4a, 4b) through the power unit (P).

Description

Technical Field

[0001] The present invention relates to a drive control device and a vehicle.

[0002] This application claims priority based on Japanese Patent Application No. 2020-54193 filed in Japan on March 25, 2020, the contents of which are incorporated herein by reference. Background Art

[0003] Conventionally, occupants of vehicles sometimes experience the impact of contact (collision) between components at the meshing points of gears and various moving parts in vehicle drive systems. This impact occurs when components mesh with each other after gaps are formed between them, such as during starting, acceleration, or deceleration.

[0004] In contrast, for example, Patent Document 1 discloses a structure for preventing backlash reduction shocks from occurring at the start of an electric vehicle in which the rotating shaft of the drive wheel is driven by an electric motor. This structure applies initial torque to the electric motor before the accelerator is operated at the start, and performs backlash reduction on the drive system of the electric motor in advance, thereby preventing backlash reduction shocks from occurring at the start. In addition, Patent Document 1 discloses a structure for controlling the drive of the electric motor to perform backlash reduction on the drive side under the following circumstances. This situation is a situation in which the driving state in which the drive wheel is driven by the driving force of the electric motor is changed to a driven state in which the electric motor is driven by the drive wheel. In addition, Patent Document 1 describes a situation in which the backlash reduction control is terminated when the rotating shaft rotates at high speed.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 4747818 Summary of the Invention

[0008] Summary of the Invention

[0009] Problems to be solved by the invention

[0010] However, there are various situations in actual vehicle driving, and if anti-backlash control is given excessive priority in all situations, it will cause discomfort to the occupants. Therefore, it is desired to further suppress this discomfort.

[0011] The present invention has been made in view of the above-mentioned actual situation, and an object of the present invention is to provide a drive control device and a vehicle that can operate a vehicle driven by a prime mover with less discomfort.

[0012] Solutions to Problems

[0013] A first embodiment of the present invention relates to a drive control device (120) for a vehicle (1) that drives drive wheels (4a, 4b) to rotate by a driving force of a power unit (P) including a prime mover (30), wherein the drive control device (120) includes a throttle (110) for adjusting the torque of the prime mover (30), and when the opening of the throttle (110) is in a fully closed state, when the running speed of the vehicle (1) is within a first speed range (preset in a region exceeding zero) V1), a torque (T1) in a first rotational direction (R1) for moving the vehicle (1) forward is imparted to the drive wheels (4a, 4b) at a constant torque value through the power unit (P); and a torque (T2) in a second rotational direction (R2) opposite to the first rotational direction (R1) is imparted to the drive wheels (4a, 4b) through the power unit (P) when the vehicle (1) is in a second speed range (V2) set to a higher speed side than the first speed range (V1).

[0014] The second embodiment of the present invention is based on the first embodiment, and is characterized in that the drive control device (120) comprises: an accelerator opening sensor (121) for detecting the opening of the accelerator (110); a vehicle speed sensor (122) for detecting the running speed of the vehicle (1); a mapping storage unit (123) for storing mapping information (Im) representing the opening of the accelerator (110), the running speed of the vehicle (1), and the torque generated by the power unit (P); and a control unit (124) for causing the power unit (P) to generate a torque corresponding to the opening of the accelerator (110) detected by the accelerator opening sensor (121) and the running speed of the vehicle (1) detected by the vehicle speed sensor (122), based on the mapping information (Im) stored in the mapping storage unit (123).

[0015] The third embodiment of the present invention is based on the second embodiment, and is characterized in that the vehicle speed sensor (122) detects the running speed of the vehicle (1) based on the rotation speed of the rotating shaft (45) driven by the prime mover (30).

[0016] The fourth scheme of the present invention is based on any one of the above-mentioned first to third schemes, and is characterized in that in a third speed range (V3) set between the first speed range (V1) and the second speed range (V2), the torque (T3) applied to the drive wheels (4a, 4b) by the power unit (P) is continuously changed.

[0017] The fifth scheme of the present invention is based on any one of the above-mentioned first to third schemes, and is characterized in that when the driving speed of the vehicle (1) is in a fourth speed range (V4) set to a lower speed side than the first speed range (V1), a torque (T4) smaller than that in the first speed range (V1) is imparted to the drive wheels (4a, 4b) through the power unit (P).

[0018] The sixth embodiment of the present invention is based on the fifth embodiment, and is characterized in that the fourth speed range (V4) includes the stopped state of the vehicle (1), and when the vehicle (1) is stopped, the torque (T4) is zero.

[0019] The seventh embodiment of the present invention is based on the fifth embodiment, and is characterized in that when the vehicle (1) is stopped, a torque (T0) greater than that in the first speed range (V1) is applied to the drive wheels (4a, 4b).

[0020] The eighth embodiment of the present invention is based on the above-mentioned fifth embodiment, and is characterized in that in a fifth speed range (V5) set between the first speed range (V1) and the fourth speed range (V4), the torque (T5) applied to the drive wheels (4a, 4b) by the power unit (P) is continuously changed.

[0021] A ninth aspect of the present invention provides a vehicle (1), characterized in that it comprises a drive control device (120) as described in any one of the first to third aspects.

[0022] Effects of the Invention

[0023] According to the first and second embodiments, when the throttle is fully closed and the vehicle is traveling in the first speed range, the following control is performed. Specifically, the power unit applies torque in the first rotational direction, which is required to propel the vehicle forward, to the drive wheels. This eliminates backlash in the drive system when the throttle is released from the fully closed position. This reduces the shock produced during vehicle acceleration.

[0024] In addition, when the throttle opening is in a fully closed state and the vehicle's driving speed is in a second speed range that is closer to the high-speed side than the first speed range, that is, when the throttle is in a fully closed state while the vehicle is traveling, the following control is performed. That is, a torque (reverse torque) in a second rotational direction opposite to the first rotational direction when the vehicle is moving forward is imparted to the drive wheels by the power unit. In this state, since the power unit does not impart torque in a direction that accelerates the vehicle, the feeling of idling caused by the driving force of the power unit can be suppressed. In addition, in this state, the power unit imparts torque in a direction that decelerates the vehicle (engine braking), thereby improving driving stability while suppressing the braking load of the vehicle. As a result, the vehicle driven by the power unit can be operated with less discomfort.

[0025] The torque imparted by the power unit within the first speed range on the low-speed side is constant, thus having a constant impact on the vehicle's low-speed travel. Consequently, passengers are less likely to feel the torque imparted by the power unit, thus minimizing any discomfort to passengers.

[0026] According to the third aspect, the vehicle speed is detected based on the rotation speed of the rotating shaft, whereby the vehicle speed can be directly detected with a simpler means.

[0027] According to the fourth embodiment, the torque imparted by the power unit is continuously varied within a third speed range between the first and second speed ranges. This reduces the sense of acceleration when the vehicle speed changes from the second speed range to the first speed range while the accelerator is still fully closed, i.e., when the vehicle decelerates. Furthermore, the occupants are less likely to feel the fluctuations in torque imparted by the power unit, thus minimizing any discomfort to the occupants.

[0028] According to the fifth aspect, when the vehicle is traveling at a lower speed, the occupants are less likely to feel the torque applied by the power unit, and the influence on the vehicle's extremely low-speed travel can be suppressed.

[0029] According to the sixth aspect, the torque applied by the power unit is zero when the vehicle is stopped, thereby preventing the vehicle from unexpectedly starting to move. Specifically, when a vehicle stops against the torque applied by the power unit, external forces may be applied to the vehicle, such as when cargo is loaded onto the vehicle or passengers are boarding or exiting the vehicle. In such cases, the vehicle could potentially start to move due to the torque applied by the power unit. By ensuring that the torque applied by the power unit is zero when the vehicle is stopped, this concern can be eliminated.

[0030] According to the seventh aspect, a torque greater than that in the first speed range is applied when the vehicle is stopped, thereby reliably eliminating backlash in the power unit. Specifically, for example, when the vehicle is starting, a greater torque is required to eliminate backlash in the power unit than when the vehicle is decelerating from a running state and then coming to a stop. Even in such a situation, backlash in the power unit can be reliably eliminated.

[0031] According to the eighth embodiment, the torque imparted by the power unit is continuously varied within the fifth speed range between the first and fourth speed ranges. This has the following advantages: Specifically, when the vehicle speed changes from the first speed range to the fourth speed range while the accelerator is still fully closed, i.e., when the vehicle shifts to an extremely low speed, the sense of acceleration can be suppressed. Furthermore, the fluctuations in the torque imparted by the power unit are less noticeable to the occupants, thereby minimizing any discomfort to the occupants.

[0032] According to the ninth aspect, by providing the drive control device as described above, it is possible to operate the vehicle driven by the power unit with less discomfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a left side view of the vehicle according to the embodiment of the present invention.

[0034] Figure 2 This is a developed cross-sectional view showing the main axes of the power unit of the above vehicle side by side.

[0035] Figure 3 This is a block diagram showing the configuration of a drive control device in the above-mentioned vehicle.

[0036] Figure 4 This is a map showing an example of mapping information used for control of the above-mentioned drive control device. DETAILED DESCRIPTION

[0037] Embodiments of the present invention are described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, references to directions such as front, rear, left, and right in the following description are identical to those in the vehicle described below. Furthermore, arrows FR indicating the front of the vehicle, LH indicating the left of the vehicle, and UP indicating the top of the vehicle are shown at appropriate locations in the drawings used in the following description.

[0038] like Figure 1 、 Figure 2As shown, the electric vehicle (vehicle) 1 of this embodiment has a front wheel 2, one of the steerable wheels, supported by a front vehicle body (vehicle front structure) 3. The electric vehicle 1 has a pair of left and right rear wheels (drive wheels) 4a, 4b, serving as drive wheels, supported by a rear vehicle body (vehicle rear structure) 5. The electric vehicle 1 is capable of swinging (rolling) the front vehicle body (swinging side vehicle body) 3, on which passengers sit, relative to the rear vehicle body (non-swinging side vehicle body) 5, which has the left and right rear wheels 4a, 4b grounded. The electric vehicle 1 is configured as a swing-type electric tricycle.

[0039] The front vehicle body 3 includes an operating handle 6 for front wheel steering and a seat 7 for passenger seating. The front vehicle body 3 defines a straddling space 8 between the operating handle 6 and the seat 7 and includes a low floor bottom surface 9 below the straddling space 8 .

[0040] The front vehicle body 3 and the rear vehicle body 5 are connected to each other via a rotation mechanism (roll joint) 50 . Figure 1 Indicated by reference numeral C1 is a rotation axis of the rotation mechanism 50 extending in the vehicle front-rear direction.

[0041] Reference Figure 1 The front vehicle body 3 includes a front vehicle body frame 11. The front vehicle body frame 11 comprises a single front frame 14 that extends downward from the rear side of the head pipe 12 and then bends rearward; a pair of left and right lower frames 15 that branch left and right from the bent portion of the front frame 14 and then extend rearward; and a pair of left and right rear frames 16 that extend from the rear ends of the left and right lower frames 15 and bend obliquely rearward and upward. A front wheel suspension device (e.g., a telescopic front fork) 13 is steerably supported on the head pipe 12. The front wheel 2 is supported by the lower end of the front wheel suspension device 13.

[0042] A lower cross frame (not shown) is disposed between lower portions of the left and right rear frames 16. A front structure 50F of the rotation mechanism 50 is fixedly supported by the lower cross frame.

[0043] When the electric vehicle 1 turns, the front body 3 swings (tilts) in the turning direction relative to the rear body 5, which has the left and right rear wheels 4a and 4b in contact with the road surface, via the turning mechanism 50. Thus, the front body 3 causes the front wheels 2, which are steerable wheels, to generate a steering angle.

[0044] The entire front body 3, including the front body frame 11, is covered by a front body cover 90. The front body cover 90 includes a front cover 91 and an inner cover 92, which cover the periphery of the head pipe 12 and the front frame 14 from the front and rear, respectively; a floor panel 93 connected to the rear of the lower end of the inner cover 92; and a seat lower cover 94, which rises behind the floor panel 93 and extends below the seat 7. The floor panel 93, together with the left and right lower frames 15 and other components, constitutes the low floor bottom surface 9. The seat lower cover 94 has a rear inclined portion 94a that slopes downward, with the front portion lower than the front and the rear portion higher than the rear.

[0045] The rear vehicle body 5 includes a rear vehicle body frame 21 that is independent of the front vehicle body frame 11. The rear vehicle body frame 21 includes a second rear frame 22 that extends obliquely upward and rearward from the rear structure 50R (non-rotating region) of the rotation mechanism 50; and a rear upper frame 23 that extends rearward from the upper end of the second rear frame 22. The second rear frame 22 and the rear upper frame 23 are, for example, integrally formed with each other. The rear vehicle body frame 21 is positioned between the left and right rear wheels 4a and 4b in the left-right direction.

[0046] The front end of the swing unit 40 is supported by the rear end of the rear structure 50R of the rotation mechanism 50. The front end of the swing unit 40 is supported for vertical swinging via a swing axis (pivot) 41 extending in the left-right direction. The rear end of the swing unit 40 is connected to and supported by the upper rear portion of the rear vehicle body frame 21 via left and right rear shock absorbers (not shown). The swing unit 40, the left and right rear shock absorbers (not shown), and the rear vehicle body frame 21 together constitute the rear wheel suspension system (rear suspension) on the rear vehicle body 5.

[0047] The entire rear body 5, including the rear body frame 21, is covered by a rear body cover 70. The rear body cover 70 includes a front wall 71 forming an inclined front surface generally parallel to the second rear frame 22; an upper wall 72 extending rearward and generally horizontally from the upper end of the front wall 71; and rear fenders 74 covering the areas above the left and right rear wheels 4a, 4b. The upper wall 72, together with the rear upper frame 23 and other components, forms a cargo rack 75 on the upper surface of the rear body 5. The front wall 71 is generally parallel to the rear inclined portion 94a of the front body 3. A gap is provided between the front wall 71 and the rear inclined portion 94a. This gap is set to prevent interference with the rear inclined portion 94a during relative swinging of the front and rear bodies 3, 5.

[0048] like Figure 2 As shown, the swing unit 40 is disposed between the left and right rear wheels 4a and 4b. The swing unit 40 is disposed so as to extend from a swing axis 41 to a rear wheel axle 42 in a side view. The swing unit 40 is disposed so that its longitudinal direction faces the front-rear direction.

[0049] The swing unit 40 is configured as a power unit P including an electric motor (prime mover) 30, which is the driving source of the electric vehicle 1. The swing unit 40 includes: a unit housing 43, which serves as a structure (swing arm) that supports the left and right rear wheels 4a and 4b so that they can swing up and down; the electric motor 30, which is housed in the front left side of the unit housing 43; and a differential mechanism 44, which is housed in the rear part of the unit housing 43. The swing unit 40 is mounted on a jib 43a (see Figure 1 ) state, it can be connected to the rotation mechanism 50 in a swingable manner.

[0050] A rotating shaft 45, a countershaft 47, and a rear wheel axle 42 are disposed within the unit housing 43. The rotating shaft 45, countershaft 47, and rear wheel axle 42 are arranged parallel to each other, with their axis centers extending in the left-right direction of the vehicle body. A motor housing 46 is housed within the front left side of the unit housing 43.

[0051] A parking lock mechanism 80 is provided on the inner side of the front portion of the power unit P. The parking lock mechanism 80 is locked so as to prevent the left and right rear wheels 4a and 4b from rotating when the vehicle is parked on a slope or the like.

[0052] The rotation shaft 45 is provided at the front portion of the unit housing 43. Figure 2 The rotating shaft 45 is the output shaft of the electric motor 30. The rotating shaft 45 is rotatably mounted in a motor housing 46 disposed within the unit case 43 via bearings 51 and 52. The electric motor 30 is mounted within the motor housing 46. The electric motor 30 includes a rotor 31 fixed radially outside the rotating shaft 45 and a stator 32 disposed radially outside the rotor 31 and fixed to the motor housing 46.

[0053] The rotating shaft 45 protrudes from the motor housing 46 toward the right side of the vehicle body. The protruding portion of the rotating shaft 45 is rotatably supported via a bearing 53a at the front end of a collar protruding from the right side of the motor housing 46. The right end of the rotating shaft 45 is rotatably supported by the right side wall of the unit case 43 via a bearing 53b.

[0054] A pinion gear 54 is provided at a portion located between the bearings 53a and 53b in the right protruding portion of the rotating shaft 45. For example, a helical gear is used as the pinion gear 54.

[0055] The countershaft 47 is located behind the vehicle body relative to the rotating shaft 45. Both ends of the countershaft 47 are rotatably supported by the unit case 43 via bearings 55 and 56. A relatively large-diameter transmission gear 57 is provided on the countershaft 47, meshing with the pinion gear 54 of the rotating shaft 45. This reduces the rotation of the rotating shaft 45 and transmits it to the countershaft 47. A pinion gear 58 is engraved on the outer circumference of the countershaft 47, on the left side of the vehicle body relative to the transmission gear 57.

[0056] The rear wheel axle 42 is provided at the rear of the vehicle with respect to the rotation axis 45 and the counter shaft 47 .

[0057] The rear wheel axle 42 includes a right axle 42R and a left axle 42L, which are coaxial and separate. The left axle 42L is rotatably supported on the left side of the unit case 43 via a bearing 59L. The center of the left rear wheel 4a is rotatably supported on the left end of the left axle 42L. The right axle 42R is rotatably supported on the right side of the unit case 43 via a bearing 59R. The center of the right rear wheel 4b is rotatably supported on the right end of the right axle 42R.

[0058] A differential mechanism 44 is provided between the right axle 42R and the left axle 42L. The differential mechanism 44 is housed in the rear right portion of the unit case 43. The differential mechanism 44 includes a differential case 61, a pair of pinion gears 62, and a pair of side gears 63.

[0059] The differential case 61 is rotatably supported by the unit case 43 via bearings 60A and 60B. A pair of pinion gears 62 are provided within the differential case 61. The pair of pinion gears 62 are pivotally supported by pins 64. A pair of side gears 63 are provided on the left and right sides of the differential case 61. The left end of the right axle 42R is spline-engaged with the right side gear 63. The right end of the left axle 42L is spline-engaged with the left side gear 63.

[0060] An output gear 65 is provided on the outer circumference of the left side of the differential case 61. The output gear 65 meshes with the pinion gear 58 formed on the countershaft 47. The output gear 65 has a larger diameter than the pinion gear 58. As a result, the rotation of the countershaft 47 is transmitted to the differential case 61 at a reduced speed. The rotation of the differential case 61 drives the rear wheel axles 42 (the right axle 42R and the left axle 42L) in rotation via the differential mechanism 44.

[0061] The electric motor 30 of the power unit P as described above is Figure 1 The electric motor 30 is driven by power from the battery 100 shown. The electric motor 30 is variable-speed driven, for example, using VVVF (variable voltage variable frequency) control. While the electric motor 30 is controlled to have a continuously variable transmission, this is not limiting and the electric motor 30 may also have a stepped transmission. The battery 100 is, for example, located below the seat 7 of the front vehicle body 3.

[0062] The electric motor 30 is Figure 4 The operation is controlled by the drive control device 120 shown in the figure. The drive control device 120 includes an accelerator opening sensor 121 , a vehicle speed sensor 122 , a map storage unit 123 , and a control unit 124 .

[0063] The throttle opening sensor 121 detects the opening of the accelerator grip (throttle) 110, located on the right side of the vehicle body relative to the operating handle 6. The throttle grip 110 is an operating element used to adjust the speed (vehicle speed) of the electric vehicle 1. The occupant operates the throttle grip 110 to adjust its opening. The electric motor 30 operates at a rotational speed corresponding to the opening of the throttle grip 110, applying a driving force (torque) corresponding to the rotational speed to the left and right rear wheels 4a and 4b.

[0064] The vehicle speed sensor 122 detects the running speed of the electric vehicle 1. The vehicle speed sensor 122 can also detect the rotation speed of the front wheels 2, for example. In this embodiment, the vehicle speed sensor 122 detects the rotation speed of the rotating shaft 45 driven by the electric motor 30, thereby detecting the running speed of the electric vehicle 1.

[0065] The mapping storage unit 123 stores preset mapping information Im (see Figure 4 The mapping information Im is used to cause the electric motor 30 to generate a torque corresponding to the opening of the accelerator grip 110. The mapping information Im is set for each opening of the accelerator grip 110. The mapping information Im sets the relationship between the running speed of the electric vehicle 1 and the torque generated by the electric motor 30 for each opening of the accelerator grip 110. Figure 4 The map information Im is information when the opening degree of the accelerator grip 110 is in the fully closed state (opening degree = 0). Figure 4 The map information Im is map information Im0 indicating the correlation between the running speed of the electric vehicle 1 and the torque generated by the electric motor 30 .

[0066] The control unit 124 controls (adjusts) the torque generated by the electric motor 30 based on the map information Im stored in the map storage unit 123 , the opening of the accelerator grip 110 detected by the accelerator opening sensor 121 , and the running speed of the electric vehicle 1 detected by the vehicle speed sensor 122 .

[0067] The PCU (Power Control Unit) 125, which is hardware, functionally includes a map storage unit 123 and a control unit 124. The map storage unit 123 is stored in a memory area included in the PCU 125. The control unit 124 is functionally implemented by executing a process based on a computer program pre-set in the PCU 125. The PCU 125 is a control unit that integrally includes, for example, a PDU (Power Driver Unit) and an ECU (Electric Control Unit).

[0068] (Torque control in drive control devices)

[0069] The control unit 124 of the drive control device 120 obtains the detection result of the opening of the accelerator grip 110 from the accelerator opening sensor 121. The control unit 124 refers to the map information Im corresponding to the obtained opening of the accelerator grip 110, stored in the map storage unit 123. When the obtained opening of the accelerator grip 110 is not fully closed, the control unit 124 refers to the map information Im corresponding to the opening. The control unit 124 generates a torque corresponding to the running speed of the electric vehicle 1 detected by the vehicle speed sensor 122 through the electric motor 30.

[0070] When the opening degree of the accelerator grip 110 obtained from the accelerator opening degree sensor 121 is in the fully closed state, the control unit 124 refers to Figure 4 The mapping information Im0 is shown.

[0071] In the mapping information Im0 when the opening of the accelerator grip 110 is in the fully closed state, in the first speed range V1 set on the low-speed side, the following effect is achieved. That is, in the electric motor 30 (power unit P), it is set to apply torque T1 in the direction (hereinafter referred to as the first rotation direction R1) in which the rear wheels 4a and 4b rotate when the electric vehicle 1 travels forward. The torque T1 is set to eliminate the backlash between the gears of the drive system in the power unit P and does not increase the travel speed of the electric vehicle 1 (does not accelerate). The torque T1 is greater than the minimum torque Tmin for eliminating the backlash in the power transmission path of the power unit P (for backlash elimination). Therefore, in this first speed range V1, when the occupant increases the opening of the accelerator grip 110, the impact caused by the collision of the gears in the drive system can be suppressed.

[0072] Furthermore, in the mapping information Im0, in the second speed range V2, where the rotational speed of the rotating shaft 45 is higher than in the first speed range V1, the following effect is achieved. Specifically, the electric motor 30 (power unit P) applies torque (reverse torque) T2 in a second rotational direction R2, which is opposite to the first rotational direction R1, to the rear wheels 4a and 4b. For example, the mapping information Im0 includes a range in which the electric motor 30 (power unit P) applies torque T2 at a constant torque value, within at least a portion of the second speed range V2.

[0073] In the second speed range V2, the accelerator handle 110 is in a fully closed state, for example, in order to decelerate during driving and the accelerator handle 110 is in a fully closed state. In such a state, the electric motor 30 generates a torque in the direction of decelerating the electric vehicle 1 (the second rotation direction R2). Therefore, the braking load of the electric vehicle 1 can be suppressed. In addition, in this state, the torque T2 in the direction of decelerating the electric vehicle 1 is imparted by the electric motor 30. Therefore, the driving stability of the electric vehicle 1 is improved. In addition, since the torque T2 imparted in the second speed range V2 includes a certain range, the influence of the torque T2 on the driving of the electric vehicle 1 can be suppressed. Therefore, it is difficult to cause discomfort to the occupants.

[0074] In the map information Im0, the third speed range V3 between the first speed range V1 and the second speed range V2 is set as follows: That is, the third speed range V3 is set so that the torque T3 applied to the rear wheels 4a and 4b by the electric motor 30 (power unit P) continuously changes.

[0075] The following describes the case where the vehicle speed changes from the second speed range V2 to the first speed range V1, i.e., deceleration, while the accelerator grip 110 is still fully closed. In this case, the torque generated by the electric motor 30 does not change stepwise, and the occupant hardly feels the change in torque T3.

[0076] In addition, in the mapping information Im0, an extremely low-speed fourth speed range V4 is set at a position closer to the lower speed side than the first speed range V1. In the mapping information Im0, when the running speed of the electric vehicle 1 is in the fourth speed range V4, it is set as follows. That is, it is set so that the electric motor 30 (power unit P) applies a torque T4 that is smaller than the torque T1 in the first speed range V1 to the rear wheels 4a and 4b. This fourth speed range V4 is an extremely low-speed area that includes the stopped state of the electric vehicle 1. When the electric vehicle 1 is stopped (the running speed is 0, that is, the state of complete stop), the torque T4 is set to 0, for example.

[0077] In this fourth speed range V4, when the electric vehicle 1 is at a lower speed, the occupants are less likely to feel the torque T4 applied by the electric motor 30. Furthermore, at extremely low speeds, such as when the electric vehicle 1 is stopped, the effects of, for example, cargo being loaded onto the electric vehicle 1 or a passenger moving forward on the electric vehicle 1 can be suppressed. In other words, when the electric vehicle 1 is stopped, the electric motor 30 can be prevented from unexpectedly applying torque, causing the electric vehicle 1 to start moving, due to the influence of external forces acting on the electric vehicle 1.

[0078] Here, in the fourth speed range V4, a torque T0 greater than the torque T1 in the first speed range V1 may be set when the electric vehicle 1 is stopped. This is because, for example, when the electric vehicle 1 is started, a torque greater than the torque required to eliminate backlash of the power unit P is required to eliminate backlash when the electric vehicle 1 is decelerated and stopped.

[0079] Furthermore, in the map information Im0, the fifth speed range V5, which is set between the first speed range V1 and the fourth speed range V4, is set as follows. Specifically, in the fifth speed range V5, the torque T5 applied to the rear wheels 4a and 4b by the electric motor 30 (power unit P) is set to continuously vary.

[0080] In this fifth speed range V5, when the vehicle speed changes from the first speed range V1 to the fourth speed range V4 while the accelerator grip 110 is kept fully closed, i.e., during deceleration, the following effects are achieved: The sense of acceleration in the electric vehicle 1 can be suppressed. Furthermore, the occupants are less likely to feel the fluctuations in the torque T5 applied by the electric motor 30.

[0081] As described above, in the drive control device 120 and the electric vehicle 1 of the embodiment, the control unit 124 performs the following control when the opening of the accelerator grip 110 is in the fully closed state. That is, when the running speed of the electric vehicle 1 is in the pre-set first speed range V1, the following torque T1 is applied to the rear wheels 4a, 4b by the electric motor 30. The torque T1 is a torque in the first rotation direction R1 when the electric vehicle 1 moves forward. Moreover, when the running speed of the electric vehicle 1 is in the second speed range V2 set to the higher speed side than the first speed range V1, the following torque T2 is applied to the rear wheels 4a, 4b by the electric motor 30. The torque T2 is a torque in the second rotation direction R2 opposite to the first rotation direction R1.

[0082] According to this configuration, when the accelerator grip 110 is fully closed and the electric vehicle 1 is traveling at a speed within the first speed range V1, the following control is performed. Specifically, the electric motor 30 applies torque T1 in the first rotational direction R1, which propels the electric vehicle 1 forward, to the rear wheels 4a and 4b. This eliminates backlash in the drive system when the accelerator grip 110 is opened from the fully closed position. Consequently, the shock generated when accelerating the electric vehicle 1 can be suppressed.

[0083] Furthermore, when the accelerator grip 110 is fully closed and the electric vehicle 1 is traveling in a second speed range V2 that is higher than the first speed range V1, the following control is performed. Specifically, when the accelerator grip 110 is fully closed while the electric vehicle 1 is traveling, the following control is performed. Specifically, the power unit P applies torque (reverse torque) T2 in a second rotational direction R2, which is opposite to the first rotational direction R1 used to propel the electric vehicle 1 forward, to the rear wheels 4a and 4b. In this state, since the electric motor 30 does not apply torque that accelerates the electric vehicle 1, the feeling of idling caused by the driving force of the electric motor 30 can be suppressed. Furthermore, in this state, the electric motor 30 applies torque T2 that decelerates the electric vehicle 1, thereby improving driving stability while suppressing the braking load on the electric vehicle 1. As a result, the electric vehicle 1 driven by the electric motor 30 can be operated with less discomfort.

[0084] Furthermore, in the first speed range V1 on the low-speed side, the control unit 124 applies torque T1 to the rear wheels 4a and 4b via the electric motor 30 at a constant torque value. This ensures that the impact on the low-speed travel of the electric vehicle 1 is constant, making it difficult for the occupants to feel the torque T1 applied by the electric motor 30. This further reduces the risk of occupants feeling uncomfortable.

[0085] Furthermore, the vehicle speed sensor 122 detects the running speed of the electric vehicle 1 based on the rotation speed of the rotating shaft 45 driven by the electric motor 30. This makes it possible to directly detect the vehicle speed using a simpler means.

[0086] Furthermore, the control unit 124 continuously varies the torque T3 applied by the electric motor 30 to the rear wheels 4a and 4b within a third speed range V3, which is set between the first speed range V1 and the second speed range V2. This prevents the sense of acceleration from occurring when the vehicle speed changes from the second speed range V2 to the first speed range V1 while the accelerator grip 110 is still fully closed, i.e., when the electric vehicle 1 is decelerating. Furthermore, the occupants are less likely to feel the fluctuations in the torque T3 applied by the electric motor 30. Consequently, any discomfort experienced by the occupants is minimized.

[0087] Furthermore, when the electric vehicle 1 is traveling at a fourth speed range V4, which is set to be slower than the first speed range V1, the control unit 124 performs the following control. Specifically, the electric motor 30 applies a torque T4, which is smaller than that in the first speed range V1, to the rear wheels 4a and 4b in the first rotational direction R1. This makes it less likely that the occupants will feel the torque T4 applied by the electric motor 30 when the electric vehicle 1 is traveling at even lower speeds. Furthermore, the effects of this on the extremely low speeds of the electric vehicle 1 can be minimized.

[0088] Furthermore, the fourth speed range V4 includes the stopped state of the electric vehicle 1. When the electric vehicle 1 is stopped, the torque T4 is zero. This prevents the electric vehicle 1 from unexpectedly starting to move while stopped. Specifically, when the electric vehicle 1 stops by overcoming the torque T4 of the electric motor 30, external forces may be applied to the electric vehicle 1, such as when cargo is loaded onto the electric vehicle 1 or when passengers are boarding or alighting from the electric vehicle 1. In this case, the electric vehicle 1 may start to move due to the torque of the electric motor 30. By setting the torque applied by the electric motor 30 to zero when the electric vehicle 1 is stopped, this concern can be eliminated.

[0089] On the other hand, if the electric vehicle 1 is equipped with a parking brake, a torque T0 greater than that within the first speed range V1 can be applied even when the electric vehicle 1 is stopped. This allows for reliable backlash elimination of the power unit P. Specifically, for example, when the electric vehicle 1 is started, a greater torque is required to eliminate backlash in the power unit P than when the electric vehicle 1 is decelerated from a running state and then stopped. Even in such a situation, backlash elimination of the power unit P can be reliably achieved.

[0090] Furthermore, the control unit 124 continuously varies the torque T5 applied by the electric motor 30 to the rear wheels 4a and 4b within a fifth speed range V5, which is set between the first speed range V1 and the fourth speed range V4. This provides the following benefits when the vehicle speed changes from the first speed range V1 to the fourth speed range V4, i.e., when the electric vehicle 1 shifts to an extremely low speed, while the accelerator grip 110 is still fully closed. Specifically, the sensation of acceleration in the electric vehicle 1 can be suppressed. Furthermore, the occupants are less likely to feel the fluctuations in the torque T5 applied by the electric motor 30. Consequently, the occupants are less likely to experience discomfort.

[0091] It should be noted that the present invention is not limited to the above-mentioned embodiments described with reference to the drawings, and various modifications are conceivable within the technical scope of the present invention.

[0092] For example, in the above embodiment, the electric vehicle 1 travels solely by the driving force of the electric motor 30 as a prime mover, but the present invention is not limited thereto. Any electric vehicle may use the electric motor 30 and may be a hybrid vehicle that utilizes both the driving force of the engine and the driving force of the electric motor 30.

[0093] In the above embodiment, the power unit P is configured with an electric motor 30 as the prime mover. However, the prime mover is not limited to the electric motor 30 and may also be an engine (internal combustion engine). Furthermore, the power unit P may include, for example, a clutch actuator, an assist motor (ACG), etc. When the power unit P employs a clutch actuator driven by an electric motor or hydraulic pressure, control can be performed as follows. Specifically, the clutch actuator actuates the clutch according to the throttle opening, thereby controlling the torque applied to the drive wheels in the forward and reverse directions.

[0094] The electric vehicle 1 is a swing-type vehicle capable of swinging (rolling) its separate front and rear bodies to the left and right. However, the electric vehicle 1 is not limited to this and can also be applied to an electric vehicle with an integrated front and rear body. Furthermore, the electric vehicle 1 is not limited to a three-wheeled vehicle with one front wheel and two rear wheels and can also be applied to a two-wheeled motor vehicle (including a bicycle and a scooter-type vehicle with a prime mover), a three-wheeled vehicle with two front wheels and one rear wheel, and a four-wheeled vehicle.

[0095] Furthermore, the electric vehicle 1 is not limited to a so-called straddle-type vehicle in which a passenger straddles the seat 7 , and may be a vehicle in which a passenger sits on a seat having a backrest.

[0096] Furthermore, the configuration in the above-described embodiment is an example of the present invention, and various changes can be made without departing from the spirit of the present invention.

[0097] Explanation of symbols

[0098] 1 Electric vehicle (vehicle)

[0099] 4a, 4b rear wheels (drive wheels)

[0100] 30 Electric motor (prime mover)

[0101] 45 Rotation axis

[0102] 110 Throttle handle (throttle)

[0103] 120 drive control device

[0104] 121 Throttle opening sensor

[0105] 122 Vehicle speed sensor

[0106] 123 Mapping Storage Unit

[0107] 124 Control Department

[0108] Im, Im 0 mapping information

[0109] P Power Unit

[0110] R1 First rotation direction

[0111] R2 Second direction of rotation

[0112] T1, T2, T3, T4, T5 torque

[0113] V1 First speed range

[0114] V2 Second speed range

[0115] V3 Third Speed ​​Range

[0116] V4 Fourth speed range

[0117] V5 Fifth speed range

Claims

1. A drive control device (120) for a vehicle (1) that transmits a driving force of a power unit (P) including a prime mover (30) via a power transmission path composed of a plurality of gears to drive drive wheels (4a, 4b) to rotate, characterized in that: The drive control device (120) includes a throttle (110) for adjusting the torque of the prime mover (30). When the running speed of the vehicle (1) is within a first speed range (V1) preset in a region exceeding zero and the throttle (110) is in a fully closed state, a torque (T1) in a first rotational direction (R1) for moving the vehicle (1) forward is applied to the drive wheels (4a, 4b) by the power unit (P) at a constant torque value, the constant torque value being greater than a minimum torque (Tmin) for eliminating backlash of each gear in a power transmission path of the power unit (P) and being a torque value of a degree that does not increase the running speed of the vehicle (1). When the vehicle (1) is traveling at a second speed range (V2) set to a higher speed than the first speed range (V1) and the throttle (110) is in a fully closed state, a torque (T2) in a second rotational direction (R2) opposite to the first rotational direction (R1) is applied to the drive wheels (4a, 4b) via the power unit (P).

2. The drive control device (120) according to claim 1, characterized in that The drive control device (120) comprises: a throttle opening sensor (121) for detecting the opening of the throttle (110); a vehicle speed sensor (122) for detecting the travel speed of the vehicle (1); a mapping storage unit (123) storing mapping information (Im) indicating correlation between the opening degree of the accelerator (110), the running speed of the vehicle (1), and the torque generated by the power unit (P); and A control unit (124) causes the power unit (P) to generate a torque corresponding to the opening of the accelerator (110) detected by the accelerator opening sensor (121) and the running speed of the vehicle (1) detected by the vehicle speed sensor (122) based on the mapping information (Im) stored in the mapping storage unit (123).

3. The drive control device (120) according to claim 2, characterized in that: The vehicle speed sensor (122) detects the running speed of the vehicle (1) based on the rotation speed of the rotating shaft (45) driven by the prime mover (30).

4. The drive control device (120) according to any one of claims 1 to 3, characterized in that: In a third speed range (V3) set between the first speed range (V1) and the second speed range (V2), the torque (T3) applied to the drive wheels (4a, 4b) by the power unit (P) is continuously changed.

5. The drive control device (120) according to any one of claims 1 to 3, characterized in that: When the running speed of the vehicle (1) is in a fourth speed range (V4) set to a lower speed side than the first speed range (V1), a torque (T4) smaller than that in the first speed range (V1) is applied to the drive wheels (4a, 4b) through the power unit (P).

6. The drive control device (120) according to claim 5, characterized in that: The fourth speed range (V4) includes a stopped state of the vehicle (1), and in the stopped state of the vehicle (1), the torque (T4) is zero.

7. The drive control device (120) according to claim 5, characterized in that: When the vehicle (1) is stopped, a torque (T0) greater than that in the first speed range (V1) is applied to the drive wheels (4a, 4b).

8. The drive control device (120) according to claim 5, characterized in that: In a fifth speed range (V5) set between the first speed range (V1) and the fourth speed range (V4), the torque (T5) applied to the drive wheels (4a, 4b) by the power unit (P) is continuously changed.

9. A vehicle (1), characterized in that It includes the drive control device (120) according to any one of claims 1 to 3.

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