Driving force control device

Abstract

To shorten the switching time between the first and second directions of rotation of a rotating electric machine. [Solution] When switching the rotation of a rotating electric machine from one of the first and second directions to the other, brake control is performed when the rotational speed in one direction is above a predetermined first rotational speed, and when the rotational speed in one direction falls below the predetermined first rotational speed, phase inversion control is performed to change the rotational direction of the rotating electric machine to the other direction. Brake control is performed above the first rotational speed to avoid rapid deceleration and protect the mechanical components. When the rotational speed is reduced to below the first rotational speed, phase inversion control is used to quickly decelerate the rotating electric machine. After the rotation is reversed to the other direction, when the rotational speed rises to the third rotational speed before the one-way clutch mechanism transmits the rotation, the drive duty cycle is reduced to mitigate the shock at the start of transmission.

Description

Technical Field

[0001] The description in this specification relates to a driving force control device used for controlling a rotating electrical machine, and is useful, for example, for controlling a rotating electrical machine used as a driving device or an auxiliary power device of a two-wheeled vehicle.

Background Art

[0002] It is known to use an electric drive device that uses a rotating electrical machine as a driving device for a two-wheeled vehicle, or a hybrid drive device that combines an internal combustion engine and a rotating electrical machine. Patent Document 1 discloses a control device for a driving force control device of a rotating electrical machine that switches between the rotation of the rotating electrical machine in a first direction and the rotation in a second direction opposite to the first direction, and controls the rotational speed in the first direction and the rotational speed in the second direction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the driving force control device described in Patent Document 1, when switching from the rotation in the first direction to the rotation in the second direction, first, the rotational speed of the rotating electrical machine is gradually decreased. Next, electromagnetic brake control is performed. Then, after the rotational speed of the rotating electrical machine in the first direction becomes zero, the rotation in the second direction is gradually increased. This is a control of first stopping the rotation in the first direction and then starting the rotation in the second direction. Therefore, it is difficult to perform the switching from the rotation in the first direction to the rotation in the second direction in a short time.

[0005] The disclosure of this case aims to shorten the time when switching the rotation of the rotating electrical machine from the rotation in the first direction to the rotation in the second direction.

Means for Solving the Problems

[0006] The first aspect of this disclosure is a drive force control device comprising: a rotating electric machine having a plurality of permanent magnets arranged in the circumferential direction and a rotor capable of transmitting rotation to a drive shaft that transmits driving force to a drive unit, and a stator fixed to a fixed cover and having a plurality of coils facing the permanent magnets; a battery electrically connected to the rotating electric machine; and a control device electrically connected to the battery and the rotating electric machine, which switches and controls the rotation of the rotating electric machine in a first direction and a second direction opposite to the first direction, and controls the rotational speed in the first direction and the rotational speed in the second direction.

[0007] Furthermore, the first drive force control device of this disclosure is interposed between the rotating electric machine and the drive shaft and includes a first one-way clutch that transmits only rotation in a first direction and a second one-way clutch that transmits only rotation in a second direction, thereby transmitting both the rotation of the rotating electric machine in the first direction and the rotation of the rotating electric machine in the second direction as rotation in the propulsion direction of the drive shaft, and also includes a speed-increasing transmission mechanism that increases the speed of the rotation of the rotating electric machine in the second direction compared to the rotation of the rotating electric machine in the first direction and transmits it as rotation in the propulsion direction of the drive shaft.

[0008] Furthermore, the first control device of this disclosure, when switching the rotation of a rotating electric machine from one of the first and second directions to the other, performs brake control when the rotational speed in one direction is equal to or greater than a predetermined first rotational speed, and performs phase inversion control to change the rotational direction of the rotating electric machine to the other direction when the rotational speed in one direction falls below the predetermined first rotational speed. In this way, by first performing brake control and then phase inversion control, it becomes possible to switch the rotation of the rotating electric machine from one direction to the other direction in a short amount of time.

[0009] Here, until the rotation direction of the rotating electric machine reverses and the one-way clutch transmits the rotation, driving force cannot be transmitted to the drive shaft. Therefore, shortening the time required for this reversal is desirable as it can improve operating performance. On the other hand, if rapid phase reversal control is performed to quickly reverse the rotation direction of the rotating electric machine, there is a risk of excessive load being generated on the mechanical components of the rotating electric machine and drive shaft. Therefore, in the first disclosure, brake control is performed above a predetermined first rotational speed, and phase reversal braking is performed when the rotational speed falls below the first rotational speed. This makes it possible to protect the mechanical components.

[0010] In addition, in brake control, the induced voltage decreases as the rotational speed decreases, and the current decreases accordingly, so the braking force also decreases as the rotational speed decreases. Therefore, when the rotational speed falls below a predetermined first rotational speed, phase inversion control is performed to switch the phase of the current to the opposite phase. By using this phase inversion control, it is possible to rapidly decelerate the rotation of a rotating electric machine in one direction.

[0011] In the second part of this disclosure, when the control device switches the rotation of a rotating electric machine from one direction to the other, it controls the rotation in the other direction with a first duty cycle when the rotational speed in the other direction is less than a third rotational speed which is a predetermined number of rotational speeds less than a predetermined second rotational speed, and controls the rotation in the other direction with a second duty cycle when the rotational speed in the other direction is between the third and second rotational speeds. The second duty cycle is smaller than the first duty cycle. The second rotational speed is set to the rotational speed at which either the first one-way clutch or the second one-way clutch begins to transmit rotation in the other direction.

[0012] When the rotation direction of the rotating electric machine reverses to the other direction, and the rotational speed in the other direction increases, one of the one-way clutches engages, and the transmission of rotation in the other direction begins. Consequently, the driving force of the rotating electric machine begins to be transmitted to the drive shaft. At this time, if the rotation of the rotating electric machine is too strong, there is a risk of acceleration shock occurring on the drive shaft. Therefore, in the second disclosure, the duty cycle at the rotational speed near the engagement of one of the one-way clutches is reduced to mitigate acceleration shock.

[0013] In the third aspect of this disclosure, the control device performs phase inversion control with a 100 percent duty cycle. By using a 100 percent duty cycle, the time required for inversion can be minimized.

[0014] In the fourth part of this disclosure, the control device performs phase inversion control by increasing the duty cycle in accordance with the decrease in rotational speed in the first direction. While setting the duty cycle to 100 percent as in the third part of this disclosure is desirable for shortening the time required for inversion, it also has a greater impact on the mechanical components of the rotating electric machine and drive shaft. Therefore, in the fourth part of this disclosure, the duty cycle is gradually increased to achieve both protection of mechanical components and a reduction in the time required for inversion.

[0015] Fifth in this disclosure, the control device performs brake control using electromagnetic brake control, which disconnects the electrical connection between all coils and the battery. Sixth in this disclosure, the control device performs brake control using regenerative brake control, which generates electricity with a rotating electric machine. Electromagnetic brake control and regenerative brake control can be adopted depending on the application. Electromagnetic brake control can shorten the time required for reversal. Regenerative brake control can recover energy during brake control.

[0016] According to a seventh aspect of the present disclosure, the rotating electrical machine is a driving device of a vehicle, and the control device switches between rotation in a first direction and rotation in a second direction according to the actual speed and the required speed of the vehicle. Moreover, a predetermined hysteresis is provided between a threshold value for switching from rotation in the first direction to rotation in the second direction and a threshold value for switching from rotation in the second direction to rotation in the first direction. By providing the hysteresis, it is possible to prevent hunting in which reversals between the first direction and the second direction frequently occur. Note that the actual speed can be calculated from the rotational speed of the drive shaft, and the required speed can be calculated using, for example, the accelerator opening degree.

[0017] According to an eighth aspect of the present disclosure, the hysteresis is made larger in a high load region than in a low load region. In a high load region such as when climbing a slope, the attenuation amount of the vehicle speed during switching is large and hunting is likely to occur, so the hysteresis in the high load region is increased to cope with this.

Brief Description of the Drawings

[0018] [Figure 1] FIG. 1 is a system configuration diagram of a hybrid drive device. [Figure 2] FIG. 2 is a perspective view showing the main constituent structure of a speed increasing transmission mechanism. [Figure 3] FIG. 3 is a configuration diagram of the speed increasing transmission mechanism shown in FIG. 2. [Figure 4] FIG. 4 is a side view of a two-wheeled vehicle equipped with a speed increasing transmission mechanism. [Figure 5] FIG. 5 is a rear view of a two-wheeled vehicle equipped with a speed increasing transmission mechanism. [Figure 6] FIG. 6 is a front view showing the state of a centrifugal clutch at the time of stopping. [Figure 7] FIG. 7 is a front view showing the state of a centrifugal clutch during rotation. [Figure 8] FIG. 8 is a perspective view showing a rotating electrical machine. [Figure 9] FIG. 9 is a perspective view in which the rotor is removed from FIG. 8. [Figure 10] FIG. 10 is a front view of a planetary gear mechanism. [Figure 11]FIG. 11 is a front view showing the state of the one-way clutch during engagement. [Figure 12] FIG. 12 is a front view showing the state of the one-way clutch during free rotation. [Figure 13] FIG. 13 is a front view for explaining the states of the first to fourth modes of the planetary gear mechanism. [Figure 14] FIG. 14 is a circuit diagram showing the rotational control of the rotating electric machine. [Figure 15] FIG. 15 is a circuit diagram showing the brake control of the rotating electric machine. [Figure 16A] FIG. 16A is a diagram showing the phase inversion control (first direction) of the rotating electric machine. [Figure 16B] FIG. 16B is a diagram showing the phase inversion control (second direction) of the rotating electric machine. [Figure 17] FIG. 17 is a timing chart showing the control of the rotating electric machine. [Figure 18] FIG. 18 is a flowchart showing the control of the rotating electric machine. <00,00109> [Figure 19] FIG. 19 is a flowchart showing the reverse control of the rotating electric machine. [Figure 20] FIG. 20 is a flowchart showing the reverse control of the rotating electric machine. [Figure 21] FIG. 21 is a diagram showing the relationship between the rotational speed of the rotating electric machine and the drive shaft torque. [Figure 22] FIG. 22 is a diagram for explaining the hysteresis of the reversal of the rotation direction of the rotating electric machine. <, [Figure 23] FIG. 23 is a flowchart showing the control considering the connection of the one-way clutch. [Figure 24] FIG. 24 is a system configuration diagram of the rotating electric machine drive device. [Figure 25] FIG. 25 is a configuration diagram of another example of the speed increasing transmission mechanism. [Figure 26] FIG. 26 is a timing chart showing another example of the control of the rotating electric machine.

Embodiments for Carrying Out the Invention

[0019] An example of the drive force control device of this disclosure will be described below with reference to the figures. The drive force control device of this disclosure can also be used in examples where the drive force is generated using only a rotating electric machine. Furthermore, the drive force control device of this disclosure can also be used in a hybrid drive system 1 that includes an internal combustion engine 100 and a rotating electric machine 200. Therefore, we will first explain an example of its use in a hybrid drive system 1.

[0020] Figure 1 shows an overview of the system configuration of the hybrid drive unit 1. The hybrid drive unit 1 is equipped with an internal combustion engine 100 and a rotating electric machine 200. The hybrid drive unit 1 in Figure 1 is also equipped with a second rotating electric machine 300. While the rotating electric machine 200 is used as a drive unit, the second rotating electric machine 300 is used as a starter when starting the internal combustion engine 100 and as a generator that generates electricity by receiving the driving force of the internal combustion engine 100.

[0021] The three-phase alternating current generated by the second rotating electric machine 300 is converted to direct current by the second control device 350 and stored in the battery 351. When the second rotating electric machine rotates as a starter, the second control device 350 converts the direct current from the battery 351 back into three-phase alternating current.

[0022] DC current from battery 351 is also supplied to the rotating electric machine 200. The rotation of the rotating electric machine 200 is controlled by control device 250. Control device 250 also converts DC current to three-phase AC to control the rotational speed. In addition to the rotational speed of the rotating electric machine 200, control device 250 also controls the direction of rotation. That is, control device 250 controls the rotational speed of the rotating electric machine 200 to rotate in a first direction (for example, forward rotation) and in a second direction opposite to this first direction (reverse rotation).

[0023] Furthermore, the hybrid drive unit 1 also includes a centrifugal clutch mechanism 400, as shown in Figure 2. The centrifugal clutch mechanism 400 does not transmit the driving force of the internal combustion engine 100 to the centrifugal clutch rotor 420 when the rotational speed of the internal combustion engine 100 is below a predetermined number, and transmits the driving force of the internal combustion engine 100 to the centrifugal clutch rotor 420 when the rotational speed of the internal combustion engine 100 is above a predetermined number. The predetermined rotational speed at which the driving force of the internal combustion engine 100 is transmitted to the centrifugal clutch rotor 420 is, for example, about 3000 rpm. The hybrid drive unit 1 also places a planetary gear mechanism 500 and a one-way clutch mechanism 600 between the rotating electric machine 200 and the centrifugal clutch mechanism 400. As will be explained later, the planetary gear mechanism 500 and the one-way clutch mechanism 600 constitute the speed-increasing transmission mechanism 1010 in this example.

[0024] As shown in Figure 2, the rotating electric machine 200, planetary gear mechanism 500, one-way clutch mechanism 600, and centrifugal clutch mechanism 400 are arranged coaxially. Figure 3 is a schematic diagram showing each of these components, and as shown in Figure 3, each component is arranged inside the fixed cover 150. The fixed cover 150 is made of aluminum or aluminum alloy, but may also be made of resin. Resin materials include fluororesin (PTFE, PFA), carbon fiber reinforced plastic (CFRP), polypropylene (PP), and polycarbonate (PC).

[0025] As shown in Figures 4 and 5, the fixed cover 150 is fixed to the vehicle body of the motorcycle 10 facing the rear wheel. More specifically, it is positioned on the side of the rear wheel's drive shaft 130 (shown in Figure 3). When the hybrid drive system 1 of this disclosure is used in the motorcycle 10, the rear wheel becomes the drive wheel 120.

[0026] The specific configurations of each of the above components will be described below. First, the internal combustion engine 100 will be described. As shown in Figure 1, in the internal combustion engine 100, a piston 101 reciprocates within a cylinder 110, and this reciprocating motion of the piston 101 is transmitted to the crankshaft 104 via a connecting rod 102 and a web 103. The crankshaft 104 is supported by bearings and rotates. The rotation of the crankshaft 104 is transmitted to the drive pulley 105. The rotation of the crankshaft 104 is also transmitted to the second rotating electric machine 300.

[0027] Next, the centrifugal clutch mechanism 400 will be described. The rotation of the drive pulley 105 is transmitted to the centrifugal clutch mechanism 400 via the belt 106, as shown in Figure 1. In the centrifugal clutch mechanism 400, as shown in Figure 2, the belt 106 is engaged with the driven pulley 410, and the driven pulley 410 rotates in response to the driving force of the belt 106. The driven pulley 410 is pivotally supported on the drive shaft 130 by a centrifugal clutch bearing 440, as shown in Figure 3. Both the drive pulley 105 and the driven pulley 410 are made of metal, and rolled steel, aluminum, or aluminum alloy can be used.

[0028] As shown in Figures 6 and 7, the centrifugal clutch mechanism 400 has three centrifugal clutch shoes 411 supported on a rotating shaft 412 and spaced approximately equally in the circumferential direction. The centrifugal clutch shoes 411 are rotatable around the rotating shaft 412, which is fixed to a driven pulley 410. When the driven pulley 410 is not rotating and the centrifugal clutch shoes 411 are not subjected to centrifugal force, they are pulled radially inward by a centrifugal clutch spring 415, as shown in Figure 6. The centrifugal clutch shoes 411 are made of aluminum, an aluminum alloy, iron, or other metal.

[0029] Figure 7 shows the state under centrifugal force. When the centrifugal force applied to the centrifugal clutch shoe 411 overcomes the tensile force of the centrifugal clutch spring 415, the centrifugal clutch shoe 411 comes into contact with the inner circumference of the centrifugal clutch rotor 420. As shown in Figure 2, a centrifugal clutch lining 413 is attached to the outer surface of the centrifugal clutch shoe 411 to increase the frictional force with the centrifugal clutch rotor 420. This centrifugal clutch lining 413 is made of a non-asbestos material.

[0030] As shown in Figure 3, the centrifugal clutch rotor 420 is supported by the drive shaft 130 that drives the rear wheel (drive wheel 120) of the motorcycle via the first one-way clutch 610 of the one-way clutch mechanism 600, which will be described later. More specifically, the rotation of the drive shaft 130 is transmitted to the drive wheel 120 via the final gear 140. Furthermore, the centrifugal clutch rotor 420 is integrally molded with a disc-shaped clutch base 421 that can rotate together with the first one-way clutch 610 and a cylindrical clutch ring 422 that is arranged on the outer circumference of the clutch base 421.

[0031] When the internal combustion engine 100 is stopped or rotating at a low speed, the driven pulley 410 is also stopped or rotating at a low speed. In this state, the centrifugal force applied to the centrifugal clutch shoe 411 is zero or less than the tensile force of the centrifugal clutch spring 415, thus maintaining the state shown in Figure 6. Therefore, the centrifugal clutch rotor 420 does not rotate. As the rotational speed of the internal combustion engine 100 increases and the rotational speed of the driven pulley 410 exceeds a predetermined level, the centrifugal force overcomes the tensile force of the centrifugal clutch spring 415, causing the centrifugal clutch shoe 411 to rotate outward around the rotation axis 412. As a result, the centrifugal clutch shoe 411 comes into contact with the inner circumferential surface of the clutch ring 422. In particular, since the centrifugal clutch lining 413 is attached to the outer circumferential surface of the centrifugal clutch shoe 411, the frictional force between the centrifugal clutch shoe 411 and the clutch ring 422 is increased. Therefore, the rotation of the driven pulley 410 is transmitted to the centrifugal clutch rotor 420, which is supported by the drive shaft 130 and rotates.

[0032] Next, the rotating electric machine 200 will be described. As shown in Figure 3, the rotating electric machine 200 is covered by a fixed cover 150. As mentioned above, the fixed cover 150 is fixed to the vehicle body at the rear of the internal combustion engine 100 of the two-wheeled vehicle, near the side of the rear wheel (drive wheel 120). The thickness of the fixed cover 150 is approximately 4 to 5 millimeters. A fixed cover bearing 151 is also located on the fixed cover 150, and the tip of the drive shaft 130 is located on this The rotating electric motor 200 is rotatably supported by a fixed cover bearing 151. A final gear 140 having a predetermined reduction ratio is positioned at the other end of the drive shaft 130, and the rotation of the final gear 140 is transmitted to the rear wheel (drive wheel 120) via the tire shaft 141. Therefore, the rotation of the rotating electric motor 200 is reduced by the final gear 140 and transmitted to the drive wheel 120. As a result, even if a rotating electric motor 200 with relatively low torque is used, the torque is increased by the final gear 140, making it possible to overcome the frictional resistance of the drive wheel 120 as it starts to rotate and to start the two-wheeled vehicle 10.

[0033] The rotor 210 of the rotating electric machine 200 is rotatably supported on the drive shaft 130 by a rotor bearing 215. Therefore, it is possible for only the drive shaft 130 to rotate, or for only the rotor 210 to rotate. Furthermore, depending on the operation of the planetary gear mechanism 500 described later, the rotor 210 can also rotate integrally with the drive shaft 130. The rotor 210 is made of iron and, as shown in Figure 3, has a disc portion 217 extending radially outward from a base portion 216 that supports the rotor bearing 215, and a cylindrical portion 211 formed on the radially outward portion of this disc portion 217. As shown in Figure 8, twelve permanent magnets 212 are arranged circumferentially inside the cylindrical portion 211. The thickness of the permanent magnets 212 is about 2 to 5 millimeters. Note that the number of permanent magnets 212 is not limited to 12, but can be set as appropriate according to the required performance, such as 20 or 24. Also, various types of permanent magnets 212 can be selected depending on the application. Strong rare-earth magnets can be used, and sometimes inexpensive ferrite magnets are used.

[0034] As shown in Figures 3 and 8, a stator 220 is arranged inside the rotor 210. The stator 220 is made by laminating multiple magnetic steel plates and integrally forms a base portion 221 that is attached to the fixed cover 150, and multiple teeth portions that extend radially outward from this base portion 221. In Figure 8, there are 18 teeth portions, but the number of teeth portions can be appropriately set according to the number of magnetic poles of the stator 220. The outer diameter of the stator 220 is about 100 to 200 millimeters, and therefore the inner diameter of the rotor 210 is such that a small gap is formed between the outer diameter of the stator 220 and the permanent magnets 212.

[0035] The base unit 221 has three stator bolt holes 223 for fixing the stator 220 to the fixing cover 150. The base unit 221 also has one sensor case bolt hole for fixing the sensor case 230 (described later) to the stator 220. However, the sensor case 230 can also be fixed to the fixing cover 150 instead of the stator 220. Furthermore, there may be two or more sensor case bolt holes.

[0036] The teeth are electrically insulated by an insulator made of an insulating resin such as polyamide, and a coil 224 made of copper or aluminum wire is wound on the insulator. Therefore, although the teeth are not shown, they are located in the area where the coil 224 is wound. Figure 9 is a perspective view of Figure 8 with the rotor 210 removed, showing the stator 220 and sensor case 230.

[0037] As shown in Figure 9, a gap 225 is formed between adjacent coils 224, and this gap 225 widens radially outward. The sensor case 230 also includes a sensor body 231 and first to third Hall sensors 232 to 234 extending from the sensor body 231 between adjacent coils 224. The first to third Hall sensors 232 to 234 are positioned in the gap 225 between adjacent coils 224.

[0038] Each Hall sensor 232-234 is approximately 2 mm x 3 mm in size, and is covered by the sensor case 230. Therefore, the figure shows the sheath portion of the sensor case 230 that houses the Hall sensors 232-234, rather than the actual Hall sensors 232-234. The sensor body 231 houses the sensor substrates of the Hall sensors 232-234 and is made of a resin material such as polyamide.

[0039] The first to third Hall sensors 232, 233, and 234 face a permanent magnet 212, which is magnetized alternately with north and south poles, and detect the position where the north and south poles alternately fluctuate. The detection positions of the first to third Hall sensors 232, 233, and 234 correspond to the energization timing of the V, W, and U phases, respectively. When the rotating electric machine 200 is used as a motor, the voltage supply to the coils 224 corresponding to the U, V, and W phases is controlled according to these detection positions. Note that the rotation angle sensors are not limited to Hall sensors 232-234; other angle sensors such as resolvers may also be used.

[0040] The second rotating electric machine 300 is also equipped with similar Hall sensors 232-234, which are used as timing signals to control the current from the coils 224 corresponding to the U, V, and W phases when the second rotating electric machine 300 is used as a generator. In addition to the Hall sensors 232-234 that detect the magnetic angles of the U, V, and W phases, the second rotating electric machine 300 is also equipped with a Hall sensor that detects the reference position of the internal combustion engine 100.

[0041] Next, the planetary gear mechanism 500 will be described. As shown in Figure 10, the planetary gear mechanism 500 includes a sun gear 501, a ring gear 502, and a plurality (4) of planetary gears 504 interposed between the ring gear 502 and the sun gear 501. The sun gear 501 is positioned on the central axis and has 16 teeth facing outwards. The ring gear 502 is positioned on the outer circumference and has 60 teeth facing inwards. The planetary gears 504 have 22 teeth facing outwards, and the teeth of the planetary gears 504 mesh with the teeth of the sun gear 501 and the teeth of the ring gear 502. The sun gear 501, ring gear 502, and planetary gears 504 are all made of carbon steel. The planetary gears 504 are rotatably held on the planetary carrier 503.

[0042] In this disclosure, the sun gear 501 is press-fitted onto the drive shaft 130, and the sun gear 501 and the drive shaft 130 rotate together. The ring gear 502 is fixed to the rotor 210 of the rotating electric machine 200 with bolts or the like (not shown). Therefore, the ring gear 502 rotates together with the rotor 210.

[0043] Furthermore, as shown in Figure 3, the planetary carrier 503 is fixed to the centrifugal clutch rotor 420 of the centrifugal clutch mechanism 400. More specifically, the centrifugal clutch rotor 420 itself forms part of the planetary carrier 503. The planetary carrier shaft 505 is fixed to the centrifugal clutch rotor 420, and the planetary gear 504 rotates around this planetary carrier shaft 505. The four planetary carrier shafts 505 are positioned equidistant from the central axis of the sun gear 501 (the central axis of the drive shaft 130). Therefore, the planetary carrier 503 and the centrifugal clutch rotor 420 rotate as a single unit. In this example, since the centrifugal clutch rotor 420 also serves as the planetary carrier 503, the mounting space can be reduced, and weight can also be reduced.

[0044] Next, the one-way clutch mechanism 600 will be described. As shown in Figure 3, the one-way clutch mechanism 600 includes a first one-way clutch 610 interposed between the centrifugal clutch rotor 420 and the drive shaft 130, and a second one-way clutch 620 interposed between the centrifugal clutch rotor 420 and the fixed cover 150.

[0045] Both the first one-way clutch 610 and the second one-way clutch 620 operate on the same principle of clutching, and as shown in Figures 11 and 12, they are equipped with an inner ring 630 fixed to the inner circumferential member and an outer ring 631 fixed to the outer circumferential member. Both the inner ring 630 and the outer ring 631 are made of carbon steel. In the first one-way clutch 610, the drive shaft 130 is fixed so as to pass through the inner ring 630, and the central axis of the inner ring 630 coincides with the central axis of the drive shaft 130. The outer ring 631 is fixed so as to fit its outer circumference onto the inner circumference of the centrifugal clutch rotor 420. The central axis of the outer ring 631 also coincides with the central axis of the drive shaft 130.

[0046] In addition, in the second one-way clutch 620, the inner ring 630 is fixed so that its inner circumference fits with the outer circumference of the centrifugal clutch rotor 420. The outer ring 631 of the second one-way clutch 620 is fixed so that its outer circumference fits with the inner circumference of the fixed cover 150. In the second one-way clutch 620 as well, the central axes of the inner ring 630 and the outer ring 631 coincide with the central axis of the drive shaft 130.

[0047] An engaging wall 633 is formed on the inner ring 630, and the gap between this engaging wall 633 and the inner circumference of the outer ring 631 decreases towards the outer ring 631 side. A cylindrical one-way clutch bar 632 is positioned between the engaging wall 633 and the inner circumference of the outer ring 631. The one-way clutch bar 632 is pressed towards the outer ring 631 side by a one-way clutch spring 635 held in a retaining hole 634 of the inner ring 630.

[0048] Figure 11 shows the meshing state of the one-way clutch mechanism 600. In this example, the inner ring 630 is rotating clockwise, or the outer ring 631 is rotating counterclockwise. That is, the relative direction of rotation between the inner ring 630 and the outer ring 631 is the direction that moves the one-way clutch bar 632 toward the outer ring 631. Due to this relative direction of rotation between the inner ring 630 and the outer ring 631, the one-way clutch bar 632 engages, and the inner ring 630 and the outer ring 631 rotate together.

[0049] Conversely, Figure 12 shows the free-rotating state of the one-way clutch mechanism 600. In this example, the inner ring 630 is rotating counterclockwise, the outer ring 631 is rotating clockwise, or both. That is, the relative rotation direction of the inner ring 630 and the outer ring 631 is the direction that moves the one-way clutch bar 632 toward the inner ring 630. Due to this relative rotation direction of the inner ring 630 and the outer ring 631, the one-way clutch bar 632 is pulled away, and the inner ring 630 and the outer ring 631 can rotate or stop freely.

[0050] The engagement direction and free-rotation direction of the one-way clutch mechanism 600 can be set to either clockwise or counterclockwise by changing the orientation of the engagement wall 633. The first one-way clutch 610 is set to transmit only the rotation of the centrifugal clutch rotor 420 in the first direction (forward rotation) to the drive shaft 130, and not the rotation in the second direction (reverse rotation). The second one-way clutch 620 is set not to allow rotation in the second direction to the centrifugal clutch rotor 420.

[0051] More specifically, the clutch mechanism of the first one-way clutch 610 transmits the rotation of the centrifugal clutch rotor 420 in a first direction between the centrifugal clutch rotor 420 and the drive shaft 130. Therefore, when the centrifugal clutch rotor 420 rotates in the first direction, that rotation is transmitted to the drive shaft 130. On the other hand, even if the drive shaft 130 rotates in the first direction, no rotation is transmitted from the drive shaft 130 to the centrifugal clutch rotor 420.

[0052] Furthermore, the second one-way clutch 620 is interposed between the centrifugal clutch rotor 420 and the fixed cover 150, and is a clutch mechanism that allows rotation of the centrifugal clutch rotor 420 only in the first direction between the centrifugal clutch rotor 420 and the fixed cover. In other words, it is a clutch mechanism that does not allow rotation of the centrifugal clutch rotor 420 in the second direction by locking the centrifugal clutch rotor 420 to the fixed cover 150.

[0053] Next, the operation of the hybrid drive system 1, which has the above configuration, will be explained. First, the first mode, in which the vehicle is driven at low speed using the driving force of the rotating electric machine 200 without using the driving force of the internal combustion engine 100, will be explained. In this first mode, since the internal combustion engine 100 is not rotating, the driven pulley 410 also does not rotate, and the centrifugal clutch rotor 420 is free from the centrifugal clutch shoe 411. In the first mode, the control device 250 controls the supply of current to the U-phase coil 353, V-phase coil 354, and W-phase coil 355 of the rotating electric machine 200 to rotate the rotor 210 in the first direction. The first direction is the direction in which the drive wheel 120 rotates in the forward direction and the two-wheeled vehicle 10 moves forward (forward rotation direction) when the drive shaft 130 rotates in the first direction.

[0054] More specifically, as shown in Figure 14, a U-phase semiconductor switch 3511, a V-phase semiconductor switch 3512, and a W-phase semiconductor switch 3513 are arranged in the high-voltage side wiring 3510. Similarly, a low-voltage U-phase semiconductor switch 3521, a low-voltage V-phase semiconductor switch 3522, and a low-voltage W-phase semiconductor switch 3523 are arranged in the low-voltage side wiring 3520. These U-phase semiconductor switches 3511, V-phase semiconductor switch 3512, W-phase semiconductor switch 3513, low-voltage U-phase semiconductor switch 3521, low-voltage V-phase semiconductor switch 3522, and low-voltage W-phase semiconductor switch 3523 are high-voltage MOSFET (metal-oxide-semiconductor field-effect transistor) semiconductors. Each switch is electrically connected to the corresponding U-phase coil 353, V-phase coil 354, and W-phase coil 355, respectively.

[0055] In the example shown in Figure 14, the U-phase semiconductor switch 3511 of the high-voltage side wiring 3510 is turned off, the V-phase semiconductor switch 3512 is turned on, and the W-phase semiconductor switch 3513 is turned off. Similarly, the low-voltage U-phase semiconductor switch 3521 of the low-voltage side wiring 3520 is turned on, the low-voltage V-phase semiconductor switch 3522 is turned off, and the low-voltage W-phase semiconductor switch 3523 is turned on. In this state, the current from the high-voltage side wiring 3510 flows from the V-phase semiconductor switch 3512 to the V-phase coil 354. Then, it flows through the neutral point 356 to the U-phase coil 353 and the W-phase coil 355, and then through the low-voltage U-phase semiconductor switch 3521 and the low-voltage W-phase semiconductor switch 3523 to the low-voltage side wiring 3520. In this embodiment, coil 224 refers collectively to these U-phase coil 353, V-phase coil 354, and W-phase coil 355.

[0056] Figures 16A and 16B show the relationship between the switching timing of each switch corresponding to the position of the rotor 210 and the current supplied to the U-phase coil 353, V-phase coil 354, and W-phase coil 355. As described above, the detection positions of the first to third Hall sensors 232, 233, and 234 correspond to the energizing timing of the V-phase, W-phase, and U-phase, and the energizing of the coils 224 of each phase is controlled according to the signals from the Hall sensors 232 to 234. The coils 224 of the energized phase are excited, causing attraction and repulsion with the permanent magnet 212, and the rotor 210 is rotated by utilizing the attractive and repulsive forces of this magnetic flux.

[0057] The switching timing of each switch is shifted by 120 degrees in electrical angle. Therefore, by switching the U-phase semiconductor switch 3511, V-phase semiconductor switch 3512, and W-phase semiconductor switch 3513, and simultaneously the low-voltage U-phase semiconductor switch 3521, low-voltage V-phase semiconductor switch 3522, and low-voltage W-phase semiconductor switch 3523 on the low-voltage side, it is possible to control the rotation direction of the rotating electric machine. In the example in Figure 16A, the high-voltage side switches can be switched in the order of W-phase semiconductor switch 3513, V-phase semiconductor switch 3512, and U-phase semiconductor switch 3511 to achieve rotation in the first direction. Conversely, in Figure 16B, the high-voltage side switches are switched in the order of U-phase semiconductor switch 3511, V-phase semiconductor switch 3512, and W-phase semiconductor switch 3513. In this case, rotation in the second direction can be achieved.

[0058] Note that Figures 16A and 16B only illustrate the switching of the high-voltage side U-phase semiconductor switch 3511, V-phase semiconductor switch 3512, and W-phase semiconductor switch 3513. This is for the sake of simplicity in explanation. As described above, the low-voltage side low-voltage U-phase semiconductor switch 3521, low-voltage V-phase semiconductor switch 3522, and low-voltage W-phase semiconductor switch 3523 are also switched in accordance with the switching of the high-voltage side U-phase semiconductor switch 3511, V-phase semiconductor switch 3512, and W-phase semiconductor switch 3513.

[0059] When the switches are turned in the order shown in Figure 16A, the stator 220 is fixed to the fixed cover 150, so the rotor 210 rotates in the first direction. The ring gear 502 of the planetary gear mechanism 500 is fixed to the rotor 210, so the ring gear 502 rotates in the first direction together with the rotor 210. The rotation of the ring gear 502 is transmitted to the planetary gear 504 that meshes with the ring gear 502, and the planetary gear 504 and planetary carrier 503 rotate in the first direction.

[0060] Furthermore, the second one-way clutch 620 is configured not to transmit the rotation of the rotor 210 of the rotating electric machine 200 in the second direction to the centrifugal clutch rotor 420, so it is free (free-spinning) in relation to the rotation in the first direction. In other words, the second one-way clutch 620 allows the centrifugal clutch rotor 420 to rotate in the first direction relative to the rotor 210.

[0061] The planetary carrier 503 has a planetary carrier shaft 505 fixed to the centrifugal clutch rotor 420, and the second one-way clutch 620 is allowed to rotate in the first direction, so the centrifugal clutch rotor 420 also rotates in the first direction. The first one-way clutch 610 is structured so that when the centrifugal clutch rotor 420 rotates in the first direction, the outer ring 631 and the inner ring 630 engage with the one-way clutch bar 632. Therefore, the rotation of the centrifugal clutch rotor 420 in the first direction is transmitted to the drive shaft 130 via the first one-way clutch 610.

[0062] The rotation direction of each gear in the planetary gear mechanism 500 in this first mode is shown in Mode 1 of Figure 13. As shown in Figure 13, in the first mode, the movement transmitted from the rotor 210 to the sun gear 501 via the drive shaft 130, causing the sun gear 501 to rotate in the first direction, coincides with the movement transmitted from the rotor 210 to the sun gear 501 via the ring gear 502 and planetary gear 504, causing the sun gear 501 to rotate in the first direction. Therefore, the rotational speed of the rotating electric machine 200 is directly transmitted to the drive shaft 130, and the drive shaft 130 rotates at the rotational speed of the rotating electric machine 200.

[0063] However, since the rotor 210 and the drive shaft 130 are rotatably supported by the rotor bearing 215, the rotational force of the rotor 210 is not directly transmitted from the sun gear 501 to the drive shaft 130. The rotational force of the rotor 210 is transmitted to the drive shaft 130 via the ring gear 502, planetary gear 504, planetary carrier 503, centrifugal clutch rotor 420, and first one-way clutch 610.

[0064] Next, we will explain a second mode in which the vehicle is driven at high speed using the driving force of the rotating electric machine 200, without using the driving force of the internal combustion engine 100. In this second mode as well, since the internal combustion engine 100 is not rotating, the centrifugal clutch rotor 420 is free from the centrifugal clutch shoe 411.

[0065] In the second mode, the control device 250 controls the energization of the U-phase coil 353, V-phase coil 354, and W-phase coil 355 to the coils of the rotating electric machine 200, causing the rotating electric machine 200 to rotate in the second direction. As a result, the rotor 210 rotates in the second direction. The centrifugal clutch rotor 420 rotates in the second direction relative to the drive shaft 130, while the first one-way clutch 610 is free. Therefore, the rotation of the drive shaft 130 in the first direction is not transmitted to the centrifugal clutch rotor 420. In other words, the centrifugal clutch rotor 420 does not receive rotational force from the drive shaft 130 side.

[0066] Conversely, the rotation of the rotor 210 in the second direction is transmitted to the centrifugal clutch rotor 420 via the ring gear 502, planetary gear 504, planetary carrier shaft 505, and planetary carrier 503. However, when the centrifugal clutch rotor 420 attempts to rotate in the second direction, the second one-way clutch 620 locks the centrifugal clutch rotor 420 against the fixed cover 150. In other words, in the second mode, the centrifugal clutch rotor 420 does not rotate in the second direction and remains stationary. This state in which the centrifugal clutch rotor 420, i.e., the planetary carrier 503, is not rotating is indicated by an "x" in Mode 2 of Figure 13.

[0067] Therefore, the rotation of the rotor 210 in the second direction is transmitted to the ring gear 502, which rotates integrally with the rotor 210, and then to the planetary gear 504. Here, since the centrifugal clutch rotor 420 is not rotating, the planetary carrier 503 is also not rotating. With respect to the non-rotating planetary carrier shaft 505, the planetary gear 504 rotates in the second direction.

[0068] Specifically, the rotation of the ring gear 502 in the second direction causes the planetary gear 504 to rotate in the second direction, and this rotation of the planetary gear 504 in the second direction is then transmitted to the sun gear 501, causing the sun gear 501 to rotate in the first direction. The rotation of the sun gear in the first direction then causes the drive shaft 130 to rotate in the first direction. The rotation direction of each gear in the planetary gear mechanism 500 in this state is shown in Mode 2 of Figure 13.

[0069] As a result, in the second mode as well, the drive shaft 130 can be rotated in the first direction (forward rotation). In the first mode, the rotational speed of the rotor 210 and the rotational speed of the sun gear 501 were in a 1:1 ratio, whereas in the second mode, the rotation of the rotor 210 (the rotation of the ring gear 502) is accelerated by the planetary gear 504 and transmitted to the sun gear 501. More specifically, the acceleration ratio or reduction ratio can be set by the gear ratio between the ring gear 502 and the planetary gear 504, or the gear ratio between the planetary gear 504 and the sun gear 501. In this example, the diameter of the ring gear 502 is large and the number of teeth of the ring gear 502 is set to be the largest, so the speed is increased by 3.75 times. While the first mode is a low-speed drive mode, this second mode is a high-speed drive mode.

[0070] Therefore, by combining the planetary gear mechanism 500 and the one-way clutch mechanism 600, the drive shaft 130 can be supplied with driving force in the propulsion direction regardless of whether the rotation direction of the rotating electric machine 200 is in the first or second direction. Furthermore, by combining the planetary gear mechanism 500 and the one-way clutch mechanism 600, the second mode can be made faster than the first mode. For this reason, the planetary gear mechanism 500 and the one-way clutch mechanism 600 can be combined to form a speed-increasing transmission mechanism 1010.

[0071] However, during the transition from the first mode to the second mode, the driving force of the rotating electric machine 200 is not transmitted to the drive shaft 130. The two-wheeled vehicle 10 continues to move forward solely due to the inertial force of the first mode. Therefore, in order to improve the driving performance of the two-wheeled vehicle 10, it is desirable to perform the transition from the first mode to the second mode as quickly as possible. On the other hand, the rotating electric machine 200 has the rotational inertia force of the rotor 210, and if the direction of rotation is reversed too abruptly, there is a risk of damaging the mechanical components.

[0072] Therefore, in this disclosure, while also considering the impact on these mechanical components, the control device 250 controls the energization of the U-phase coil 353, V-phase coil 354, and W-phase coil 355 to minimize the time required for the reversal from the first direction to the second direction. This control at the switching timing from the first mode to the second mode will be explained using the timing chart shown in Figure 17.

[0073] In Figure 17, the horizontal axis represents time, and the vertical axis shows the operating status of each device. The top row shows the rotational speed of the rotor 210 of the rotating electric machine 200. The second row from the top shows the rotational speed of the drive shaft 130. The third row from the top shows the rotational speed deviation of the one-way clutch mechanism 600. The bottom row shows the throttle opening of the motorcycle 10.

[0074] First, the behavior will be explained based on the rotational speed of the rotor 210 of the uppermost rotating electric machine 200. On the vertical axis, values ​​above 0 indicate rotation in the first direction, and values ​​below 0 indicate rotation in the second direction. On the time axis, between t0 and t1 (T100), the rotor 210 is stationary. The start of the first mode is at time t1, and the control device 250 performs the control shown in Figure 16A. Next, the control device 250 calculates a predetermined target duty cycle required from the accelerator opening and gradually increases the duty cycle until that target duty cycle is reached. Note that the vehicle speed does not reach the required vehicle speed at the time the target duty cycle is reached (time t1 in Figure 17). The required speed is shown as the required rotational speed v10 of the drive shaft 130 in Figure 17. The control device 250 calculates the target duty cycle so that the required speed v10 is reached, but it takes time for the rotational speed of the drive shaft 130 to converge even after the target duty cycle is reached. For this reason, the rotational speed of the rotor 210 is increased as the target duty cycle. The period between t1 and t2 on the time axis (T101) represents the acceleration operation in this first mode. In other words, the control device 250 controls the target duty cycle so that the vehicle speed reaches the required speed according to the accelerator opening at time t2. Time t2 is also the timing when the rotation direction of the rotating electric machine 200 is reversed from the first direction to the second direction. The rotational speed of the rotor 210 at this timing is n1.

[0075] When the reversal timing t2 is reached, the control device 250 performs rotation direction reversal control. This rotation direction reversal control first performs electromagnetic brake control. As shown in Figure 15, this electromagnetic brake control turns off the high-voltage side U-phase semiconductor switch 3511, V-phase semiconductor switch 3512, and W-phase semiconductor switch 3513. Conversely, the low-voltage side low-voltage U-phase semiconductor switch 3521, low-voltage V-phase semiconductor switch 3522, and low-voltage W-phase semiconductor switch 3523 are all turned on. As a result, the U-phase coil 353, V-phase coil 354, and W-phase coil 355 are disconnected from the battery 351, and a closed electrical circuit is formed by the U-phase coil 353, V-phase coil 354, and W-phase coil 355 and the low-voltage U-phase semiconductor switch 3521, low-voltage V-phase semiconductor switch 3522, and low-voltage W-phase semiconductor switch 3523. As the rotor 210 rotates, an induced voltage (current) flows, and this current, combined with the electrical resistance of the closed electrical circuit, generates Joule heat. In this way, electromagnetic brake control is a control method that brakes the rotation of the rotor 210 by converting its rotational energy into thermal energy. Furthermore, the mechanical friction generated in the planetary gear 504 and fixed cover bearing 151, etc., as the planetary gear mechanism 500 and the drive shaft 130 rotate also contributes to assisting the brake control.

[0076] The control device 250 continues this electromagnetic brake control until the rotational speed of the rotor 210 decreases to the first rotational speed n2. The time interval between t2 and t3 (T102) is the rotational direction reversal control, and this reversal control is performed using electromagnetic brake control. When the rotational speed of the rotor 210 decreases to the first rotational speed n2, the control device 250 switches the rotational direction reversal control from electromagnetic brake control to phase reversal control.

[0077] This is because the rotational speed reduction effect of electromagnetic brake control decreases as the rotational speed decreases. Phase inversion control is performed by inverting the rotational phase in the first direction, as shown in Figure 16A, to the rotational phase in the second direction, as shown in Figure 16B. This phase inversion control uses the power of the battery 351 to actively apply a force in the opposite direction to the rotor 210 of the rotating electric machine 200. As a result, a stronger effect can be applied to the rotor 210 of the rotating electric machine 200 than with the electromagnetic brake control described above. In this example, in order to increase this drag force, voltage is applied to the U-phase coil 353, V-phase coil 354, and W-phase coil 355 with a duty cycle of 100 percent in the phase inversion control.

[0078] Phase inversion control allows the rotation of the rotor 210 of the rotating electric machine 200 to be stopped in a shorter time. For this reason, it is conceivable to start the rotation direction reversal control with phase inversion control without performing the electromagnetic brake control described above. In that case, it is conceivable to start with a small duty cycle and increase the duty cycle to 100 percent. However, this would place a correspondingly greater stress on the mechanical components of the rotating electric machine 200. In this disclosure, the rotational speed of the rotor 210 of the rotating electric machine 200 is reduced to a first rotational speed n2 by electromagnetic brake control, thereby reducing the stress on the mechanical components. Furthermore, since phase inversion control actively generates rotational force on the rotor 210, it consumes power from the battery 351. As mentioned above, electromagnetic brake control does not utilize power from the battery 351, so starting the rotation direction reversal control with brake control is more energy-efficient.

[0079] Time t4 is the point at which the rotational speed of the rotor 210 of the rotating electric machine 200 becomes zero. Therefore, the period between t3 and t4 on the time axis (T103) is the process of reducing the rotational speed in the first direction by phase inversion control. In this example, the control device 250 continues to control the rotational phase in the second direction at a duty cycle of 100 percent even after time t4, when the rotational speed of the rotor 210 becomes zero. This increases the rotational speed of the rotor 210 of the rotating electric machine 200 in the second direction.

[0080] The rotational speed n4 shown in Figure 17 is the second rotational speed n4, which is determined from the rotational speed difference between the inner ring 630 and the outer ring 631 of the second one-way clutch 620. Since this second rotational speed n4 is rotation in the second direction, the first one-way clutch 610, which transmits rotation only in the first direction, is in the free-spinning state shown in Figure 12. The second one-way clutch 620, which transmits rotation only in the second direction, is also still in the free-spinning state below the second rotational speed n4. However, when the rotational speed reaches the second rotational speed n4, the second one-way clutch 620 enters the engaged state shown in Figure 11. Therefore, from this second rotational speed n4 onwards, the second one-way clutch 620 is responsible for the engaged state necessary to maintain rotation in the first direction on the drive shaft 130.

[0081] Then, near this second rotational speed n4, the third rotational speed n3 is a predetermined amount lower than the second rotational speed n4. Therefore, the third rotational speed n3 is the rotational speed at which, if the rotational speed increases a little more, the second one-way clutch 620 will transition from a free-spinning state to a engaged state. For this reason, when the rotational speed reaches this third rotational speed n3, output adjustment is initiated to reduce the shock when the second one-way clutch 620 engages.

[0082] In this example, the period between t4 and t5 (T104) on the time axis, from rotational speed 0 to the third rotational speed n3, is the second-direction rotational speed acceleration control within the rotational direction reversal control. In this second-direction acceleration control, the duty cycle of 100 percent (first duty cycle d1) is maintained. This achieves a rapid acceleration in the second direction. However, when the rotational speed exceeds the third rotational speed n3, the duty cycle is reduced to the second duty cycle d2. By reducing the duty cycle to the second duty cycle d2, the acceleration of rotation in the second direction within the rotational direction reversal control is mitigated. This acceleration mitigation control prevents a large shock from being applied when the second one-way clutch 620, which transmits rotation in the second direction, engages. This second-direction rotational speed mitigation control continues until the rotational speed increases to the second rotational speed n4. On the time axis, this is between t5 and t6 (T105).

[0083] When the rotational speed of the rotor 210 of the rotating electric machine 200 exceeds the second rotational speed n4, the driving force of the rotating electric machine 200 is transmitted to the drive shaft 130, and the rotational speed of the rotor 210 is controlled according to the speed required for the motorcycle 10. From t6 onwards (T106) on the time axis, the operation control is in the second mode.

[0084] The above explanation focused on the rotational speed of the rotor 210 of the rotating electric machine 200 shown in the uppermost part of Figure 17. However, as mentioned above, Figure 17 also explains the speed of the drive shaft 130, the rotational speed deviation of the second one-way clutch 620, the duty cycle control, and the throttle opening of the motorcycle 10 in correspondence with the rotational speed of the rotor 210. In the example above, since it was a switch from the first mode to the second mode, the one-way clutch that initiates rotational transmission was explained as the second one-way clutch 620. Conversely, when switching from the second mode to the first mode, the first one-way clutch 610 initiates rotational transmission. In that case, the second rotational speed n4 mentioned above can be obtained from the rotational speed deviation between the inner ring 630 and the outer ring 631 of the first one-way clutch 610.

[0085] Since the motorcycle 10 starts operating at time t1, the throttle opening is increasing from time t1. In this example, the throttle opening remains constant thereafter, so as described above, the control device sets a target duty cycle to achieve the required speed corresponding to the throttle opening and accelerates the motorcycle 10. Between t1 and t2 on the time axis (T101), the motorcycle 10 accelerates in the first mode. During this time (T101), the duty cycle is kept constant (target duty cycle), and the rotational speed of the drive shaft 130 is gradually increased. Also, during this time (T101), the first one-way clutch 610 is engaged, and the second one-way clutch 620 is free-spinning. Note that the control device 250 does not calculate the target duty cycle based solely on the throttle opening. Although the throttle opening is a major parameter in calculating the target duty cycle, the actual speed of the motorcycle 10 is also taken into consideration. Furthermore, in the third and fourth modes, which will be described later, the output of the internal combustion engine 100 is also a major factor to consider.

[0086] As the speed of the motorcycle 10 increases and the rotational speed of the drive shaft 130 reaches a predetermined rotational speed, the control device 250 starts reversal control to switch from the first mode to the second mode. In the example above, the rotational speed of the rotor 210 of the rotating electric machine 200 was used for explanation, but the control of the motorcycle 10 is controlled according to the speed of the motorcycle 10. At a speed of about 10 kilometers per hour, the rotational speed of the drive shaft 130 and the rotational speed of the rotor 210 of the rotating electric machine 200 will be corresponding to that speed.

[0087] While the control device 250 is performing reversal control (T102~T105), no driving force is applied to the drive shaft 130, so the rotational speed of the drive shaft 130 gradually decreases. The first one-way clutch 610 goes from a engaged state to a free-spinning state, but at time t2 immediately after the engagement state ends, the rotational speeds of the inner ring 630 and the outer ring 631 are almost the same. Subsequently, as the rotational speed of the rotor 210 of the rotating electric machine 200 decreases due to the electromagnetic brake control and phase reversal control of the reversal control, the rotational speed of the outer ring 631 of the first one-way clutch 610 also decreases.

[0088] On the other hand, during operation in the first mode (T101), the inner ring 630 of the second one-way clutch 620 increases its rotational speed in sync with the rotor 210 and the clutch ring 422. At the start of switching (t2), the inner ring 630 of the second one-way clutch 620 rotates in the first direction at the same rotational speed as the rotor 210. Here, the outer ring 631 is fixed to the fixed cover 150 and does not rotate, so the rotational speed deviation is at its maximum. From this state, as the rotational speed of the inner ring in the first direction decreases in accordance with the decrease in the rotational speed of the rotor 210, the rotational speed deviation becomes smaller. Then, the reversal control (T102 and T103) until time t4 when the rotational speed of the rotor 210 of the rotating electric machine 200 becomes 0 reduces the rotational speed deviation by brake control (T102) and phase reversal control (T103). Furthermore, the rotational speed difference between the inner ring 630 and the outer ring 631 of the second one-way clutch 620 decreases as the rotational speed of the rotor 210 of the rotating electric machine 200 in the second direction increases. The time t5 at which this rotational speed difference decreases to a certain extent corresponds to the time when the rotational speed of the rotor 210 of the rotating electric machine 200 reaches the third rotational speed n3. As described above, the control device 250 reduces the duty cycle to a second duty cycle d2 which is smaller than the first duty cycle d1, in preparation for the inner ring 630 and the outer ring 631 of the second one-way clutch 620 to engage (T105).

[0089] At time t6, the inner ring 630 and outer ring 631 of the second one-way clutch 620 engage, and the rotational speed deviation becomes zero. Also, the rotational direction reversal control by the control device 250 ends at this time t6. After time t6, the control device 250 performs operation control in the second mode (T106), increasing the rotational speed of the rotor 210 of the rotating electric machine 200 according to the accelerator opening. The rotational speed of the drive shaft 130 also increases accordingly, and the rotational speed of the drive wheels 120 also increases. In response to the increase in the rotational speed of the drive wheels 120, the motorcycle 10 is accelerated.

[0090] Once acceleration in the second mode is complete, the next mode is the third mode, in which the rotating electric machine 200 does not rotate and only the internal combustion engine 100 rotates. In this third mode, the rotation of the crankshaft 104 of the internal combustion engine 100 is transmitted from the drive pulley 105 to the driven pulley 410 via the belt 106. As a result, the driven pulley 410 also rotates around the drive shaft 130. This rotation of the driven pulley 410 is transmitted to the centrifugal clutch shoe 411 via the rotating shaft 412, so centrifugal force is applied to the centrifugal clutch shoe 411. As a result, when the rotational speed of the rotating shaft 412 exceeds a predetermined speed, the centrifugal clutch shoe 411 is pressed against the centrifugal clutch rotor 420 with sufficient pressure, and the centrifugal clutch rotor 420 rotates together with the driven pulley 410. The direction of rotation of this centrifugal clutch rotor 420 is the first direction.

[0091] In this configuration, the centrifugal clutch rotor 420 rotates in the first direction due to the driving force of the internal combustion engine 100, and does not receive rotational force in the first direction from the rotating electric machine 200. Therefore, the first one-way clutch 610 is free between the centrifugal clutch rotor 420 and the drive shaft 130. Similarly, the second one-way clutch is also free from the fixed cover 150, allowing the centrifugal clutch rotor 420 to move in the first direction. Consequently, the rotation of the centrifugal clutch rotor 420 in the first direction causes the planetary carrier shaft 505 of the planetary carrier 503 to rotate in the first direction. The rotation of the planetary carrier shaft 505 in the first direction is rotation around the central axis of the drive shaft 130.

[0092] When the centrifugal clutch shoe 411 of the centrifugal clutch mechanism 400 is pressed against the centrifugal clutch rotor 420, and the centrifugal clutch rotor 420 begins to rotate, a small amount of starting torque is applied to the planetary carrier 503. Therefore, the control device 250 performs brake (regenerative) control to suppress the rotation of the rotating electric machine 200, increasing the magnetic friction of the rotating electric machine 200. As a result, even when the centrifugal clutch shoe 411 is pressed against the centrifugal clutch rotor 420, the rotor 210 does not rotate. In other words, the ring gear 502 is stopped. In mode 3 of Figure 13, the stopping of the ring gear 502 is indicated by an "X".

[0093] Furthermore, the torque fluctuations applied to the rotor 210 of the rotating electric machine 200 when the centrifugal clutch rotor 420 starts rotating are also reduced by the first and second modes. That is, the motorcycle 10 is started in the first mode, and then its speed is increased in the second mode. Therefore, when the internal combustion engine 100 is started in the third mode, the motorcycle 10 is already traveling at a predetermined speed. Consequently, at the point when the centrifugal clutch shoe 411 is pressed against the centrifugal clutch rotor 420 and the centrifugal clutch rotor 420 starts rotating, the rotor 210, ring gear 502, sun gear 501, and drive wheel 120 are already rotating. As a result, the torque fluctuations applied to the rotor 210 via the planetary carrier 503, planetary carrier shaft 505, and ring gear 502 when the centrifugal clutch rotor 420 starts rotating are reduced.

[0094] In the third mode, the rotating electric machine 200 is stopped, and the ring gear 502 is also stopped. As a result of the rotation of the centrifugal clutch rotor 420 in the first direction, the planetary carrier 503, which is integrated with the centrifugal clutch rotor 420, also rotates in the first direction. Consequently, the planetary gear 504 rotates along the inner circumference of the ring gear 502. In this case, the direction of rotation of the planetary gear 504 around the planetary carrier shaft 505 is the second direction. That is, the planetary carrier shaft 505 rotates in the first direction, but the direction of rotation of the planetary gear 504 is the second direction.

[0095] In this case, the sun gear 501 is meshed with the planetary gear 504, so the rotation of the planetary gear 504 in the second direction is transmitted to the sun gear 501, causing the sun gear 501 to rotate in the first direction. The rotation of the sun gear 501 in the first direction is transmitted to the drive shaft 130, causing the drive wheel 120 to rotate in the first direction (forward rotation). The rotation direction of each gear in the planetary gear mechanism 500 in this case is shown in Mode 3 of Figure 13.

[0096] Therefore, in the third mode, the driving force of the internal combustion engine 100 is transmitted to the drive shaft 130 as follows. First, the centrifugal clutch rotor 420 is rotated in the first direction via the centrifugal clutch mechanism 400 from the driven pulley 410. Next, the centrifugal clutch rotor 420 rotates the planetary carrier 503 (planetary carrier shaft 505) in the first direction, and this rotation, through the meshing of the ring gear 502 and the planetary gear 504, rotates the planetary gear 504 in the second direction. Next, the sun gear 501 is rotated in the first direction through the meshing of the planetary gear 504, and the drive wheel 120 is rotated in the first direction.

[0097] When the driving force of the internal combustion engine 100 is steadily transmitted to the drive shaft 130, fluctuations in the torque applied to the centrifugal clutch rotor 420 from the internal combustion engine 100 side become small. Therefore, in steady-state operation, the control device 250 does not perform brake (regenerative) control to suppress the rotation of the rotating electric machine 200.

[0098] In other words, under steady-state operation, the coils of the rotating electric machine 200 are not energized. Even without energization, the rotating electric machine 200 generates torque that suppresses the rotation of the rotor 210 due to the attractive force of the permanent magnets 212. Therefore, the rotor 210 is stopped by this rotation-suppressing torque from the permanent magnets 212. In this stopped state of the rotor 210, if the load torque of the drive wheel 120 increases, the rotational speed of the drive shaft 130 and the sun gear 501 decreases because the ring gear 502 is stopped.

[0099] As a result, the decrease in the rotational speed of the sun gear 501 is transmitted to the centrifugal clutch rotor 420 via the planetary gear 504 and planetary carrier 503 (planetary carrier shaft 505), causing the rotational speed of the centrifugal clutch rotor 420 to also decrease. And as long as the centrifugal clutch mechanism 400 is not disengaged, the rotational speed of the internal combustion engine 100 will also decrease. In other words, during normal operation of the internal combustion engine 100, torque fluctuations associated with acceleration and deceleration can be absorbed by the rotational suppression torque of the permanent magnet 212 of the rotating electric machine 200, and the ring gear 502 does not rotate. More specifically, if the value obtained by dividing the rotational suppression torque of the rotating electric machine 200 by the reduction ratio between the ring gear 502 and the planetary gear 504 is greater than the value obtained by dividing the rolling torque fluctuation of the drive wheel 120 by the reduction ratio of the final gear 140, and then further dividing by the reduction ratio between the sun gear 501 and the planetary gear 504, then the rotation of the ring gear 502 can be prevented.

[0100] The fact that the ring gear 502 does not rotate means that the rotor 210 does not rotate, and therefore no relative rotation occurs between the rotor 210 and the stator 220 of the rotating electric machine 200. As a result, no magnetic friction loss occurs in the rotating electric machine 200. In this disclosure, magnetic friction loss refers to iron loss caused by the alternating magnetic flux applied from the permanent magnets 212 of the rotor 210 to the stator 220. The main causes of iron loss are eddy current loss and hysteresis loss.

[0101] Even when the rotating electric machine 200 performs zero torque control by phase control of the energizing current of the U-phase coil 353, V-phase coil 354, and W-phase coil 355, magnetic friction loss is not eliminated. This magnetic friction loss ultimately consumes the output of the internal combustion engine 100, worsening the fuel efficiency of the internal combustion engine 100. In contrast, in this disclosure, there is no need to perform zero torque control and no power is supplied to the rotating electric machine 200, so as described above, no magnetic friction loss occurs.

[0102] In this example, a planetary gear mechanism 500 is used as a mechanism to prevent magnetic friction loss in the rotating electric machine 200. Therefore, this example does not require special actuators or the like to reduce magnetic friction loss, resulting in a simple structure. Although some mechanical friction loss occurs due to the rotation of the planetary gear mechanism 500, this mechanical friction loss is very small compared to the magnetic friction loss of the rotating electric machine 200. Therefore, even if the rotating electric machine 200 is added as the hybrid drive unit 1, the factor causing a decrease in the fuel efficiency of the internal combustion engine 100 due to the rotating electric machine 200 is small. Since the rotating electric machine 200 is used as the hybrid drive unit 1, an improvement in the fuel efficiency of the internal combustion engine 100 can be expected.

[0103] Next, we will explain the fourth mode, which utilizes the driving force of the rotating electric machine 200 in addition to the driving force of the internal combustion engine 100. In this fourth mode as well, the driven pulley 410 rotates, so the centrifugal clutch shoe 411 rotates together with the rotating shaft 412. As a result, the centrifugal force accompanying the rotation presses the centrifugal clutch shoe 411 against the centrifugal clutch rotor 420, and the centrifugal clutch rotor 420 rotates in the first direction together with the driven pulley 410.

[0104] In this fourth mode, the control device 250 controls the supply of U-phase, V-phase, and W-phase current to the coils of the rotating electric machine 200, causing the rotor 210 to rotate in the second direction. Therefore, the direction in which force is applied from the centrifugal clutch rotor 420 to the drive shaft 130 as the rotating electric machine 200 rotates is the same as in the second mode. As a result, the first one-way clutch 610 is in a free state between the centrifugal clutch rotor 420 and the drive shaft 130.

[0105] In the second one-way clutch, as in the third mode, the centrifugal clutch rotor 420 is free from the fixed cover 150 to move in the first direction. Therefore, as in the third mode, the rotation of the centrifugal clutch rotor 420 in the first direction causes the planetary carrier 503 (planetary carrier shaft 505) to rotate in the first direction.

[0106] In the third mode, the rotor 210 is stationary, whereas in the fourth mode, the rotor 210 rotates in a second direction. This rotation of the rotor 210 in the second direction accelerates the rotation of the planetary gear 504 in the second direction. This acceleration of the planetary gear 504 in the second direction then accelerates the rotation of the sun gear 501 in the first direction. As a result, the driving force of the rotating electric machine 200 is added to the driving force of the internal combustion engine 100 in the third mode. The rotation direction of each gear of the planetary gear mechanism 500 in this case is shown in Mode 4 of Figure 13.

[0107] In other words, the rotation directions of the planetary carrier 503, planetary gear 504, and sun gear 501 are the same in the third and fourth modes. The centrifugal clutch rotor 420, planetary carrier 503 (planetary carrier shaft 505), and sun gear 501 are in the first direction, while the planetary gear 504 is in the second direction. In the third mode, the rotation was solely due to the internal combustion engine 100, whereas in the fourth mode, the rotation of the rotating electric machine 200 is added. As a result, in the fourth mode, it is possible to achieve operation in which the rotating electric machine 200 assists the internal combustion engine 100. It should be noted that while the first and second modes are electric driving modes using only the rotating electric machine 200, this fourth mode can be said to be an assist mode in which the rotating electric machine 200 assists the internal combustion engine 100. The third mode can be said to be an engine driving mode.

[0108] The overview of each of the first to fourth modes has been described above. Next, the switching from the first mode to the second mode and from the second mode to the first mode by the control device 250 will be explained using the flowchart shown in Figure 18. The control flow starts in step S100, and the state of the motorcycle 10 is detected in step S101. In step S101, the accelerator opening and the speed of the motorcycle 10 are among the things that are detected.

[0109] In step S101, a determination is made as to whether or not the driving force of the rotating electric machine 200 is required, based on the state of the motorcycle 10 detected by this step (step S102). In the example above, the driving force of the rotating electric machine 200 was used in the fourth mode in addition to the first and second modes, but the following explanation does not mention its use in combination with the internal combustion engine 100. The switching from the first mode to the second mode and the switching from the second mode to the first mode will be explained.

[0110] If the driving force of the rotating electric machine 200 is not required in the determination step S103 (No), the driving of the rotating electric machine 200 is stopped (step S104). If the driving force of the rotating electric machine 200 is required in the determination step S103 (Yes), the rotation direction of the rotating electric machine 200 is then determined (step S105).

[0111] If the rotation direction is the first direction, it is controlled in the first mode. At the start of operation in the first mode, the rotational speed of the rotating electric machine 200 is strictly 0, but if there is a drive request (step S103), the state of rotational speed being 0 is included in the rotation in the first direction. If the rotation direction is the second direction, it is controlled in the second mode.

[0112] If the system is in the first mode, step S106 calculates the transition threshold for inversion control to determine if a switch to the second mode is necessary. If the system is in the second mode, step S107 calculates the transition threshold for inversion control to determine if a switch to the first mode is necessary. This threshold calculation will be explained using Figure 21. In the first mode, the rotational speed of the rotor 210 of the rotating electric machine 200 directly becomes the rotational speed of the drive shaft 130. On the other hand, in the second mode, the rotational speed of the rotor 210 of the rotating electric machine 200 is increased to become the rotational speed of the drive shaft 130. Therefore, when the vehicle speed of the motorcycle 10 (rotational speed of the rotor 210 of the rotating electric machine 200) is low, the first mode can provide a higher driving torque for the drive shaft 130 than the second mode. Conversely, when the vehicle speed of the motorcycle 10 (rotational speed of the rotor 210 of the rotating electric machine 200) is high, the second mode can provide a higher driving torque for the drive shaft 130 than maintaining the first mode.

[0113] In Figure 21, the drive torque in the first mode is shown by a solid line, and the drive torque in the second mode is shown by a dashed line. Both the solid and dashed lines show Tr1 at the top, driving the rotating electric machine 200 with a duty cycle of 100 percent. Tr2 at the bottom shows the drive torque when the duty cycle is set to 50 percent. As shown in Figure 21, the rotational speed at which the drive torque reverses is approximately constant, regardless of the duty cycle of the rotating electric machine 200.

[0114] Figure 22 is a map used to select between the first mode and the second mode. As shown in the map, both the first threshold Nr1, which switches from the first mode to the second mode, and the second threshold Nr2, which switches from the second mode to the first mode, are set close to the rotational speed at which the drive torque reverses. The reason why the first threshold Nr1 is set higher than the second threshold Nr2 is that hysteresis is introduced between the first threshold Nr1 and the second threshold Nr2 to prevent hunting.

[0115] In Figure 22, the first threshold Nr1 for switching from the first mode to the second mode is kept constant regardless of the accelerator opening. The reason for this is that, as shown in Figure 21, the intersection point of the first-direction rotation characteristics and the second-direction rotation characteristics, based on the relationship between drive torque and vehicle speed, is the rotational speed at which the switch between the first and second modes occurs. Furthermore, the rotational speed at which this intersection occurs does not change with the accelerator opening (duty cycle of the rotating electric machine 200) in relation to the drive torque. Therefore, considering the use of the rotational direction with the largest drive torque regardless of the accelerator opening, the rotational speed of the first threshold Nr1 for switching from the first mode to the second mode is always kept constant.

[0116] Conversely, the rotational speed of the second threshold Nr2, which switches from the second mode to the first mode, is set to be lower as the throttle opening is increased. The reason for this is that the region where the speed does not increase despite a large throttle opening is considered to be a high-load region such as an uphill slope. In this high-load region, when attempting to switch from the first mode to the second mode in order to accelerate, there is a time (T102~T105) during which the driving force of the rotating electric machine 200 is not transmitted to the drive shaft 130 during the switch. In this disclosure, this time is made as short as possible, but it cannot be made zero. As a result, in high-load regions such as uphill slopes, the deceleration that occurs during the switch makes it easier to return to the first mode region. Thus, in high-load regions (uphill slopes), the amount of vehicle speed attenuation during the switch is large and hunting is likely to occur, so the hysteresis is increased according to the throttle opening (duty cycle). Note that the characteristics of the first mode and the second mode shown by solid lines in Figure 22 represent the steady speed under normal load when driving on a flat surface.

[0117] Returning to the flowchart in Figure 18, in step S106 a decision value (threshold) is calculated based on the map, and the result of this calculation is used to determine whether to maintain the first mode (Yes) or switch to the second mode (No) (step S108). If it is determined that to switch to the second mode (No), in step S109 control is performed to switch the rotation direction of the rotating electric machine 200 to the second direction of rotation. This switching control (step S109) includes electromagnetic brake control, phase inversion control, control at the first duty cycle d1, and control at the second duty cycle d2, as explained using Figure 17.

[0118] If it is determined that the first mode should be maintained (Yes), then it is determined whether rotation direction switching control is in progress (step S110). This is because the determination in step S110 is based on the premise that the operating range of the first mode is being maintained, and the system will not transition to a normal drive request for the first mode until the rotation direction reversal control from the second mode to the first mode is completed. In other words, the determination in step S110 is made when the control loop has completed a rotation direction reversal control that switches modes, after the previous determination flow determined that the control should switch from the second mode to the first mode. This is because when the control loop has completed a rotation direction reversal control, it is necessary to maintain the control determined in the previous determination until the switching control from the second mode to the first mode is completed. Note that in step S110, it may have been determined in step S108 that the system should switch to the second mode, but the control loop has completed a rotation during the mode switching control, and the next determination will be that the first mode should be maintained. This can occur when the predetermined time required for switching modes (T102-T105) is longer than the time it takes to run the control loop shown in Figure 18.

[0119] Therefore, if it is determined in step S110 that a mode switch is in progress (Yes), the rotation direction reversal control that switches the operation from the second mode to the first mode is maintained until the switch is complete. If it is not a mode switch (No), operation in the first mode continues (step S112).

[0120] The above explanation describes the operation in the first mode, but the same steps are performed in the second mode. The threshold calculation in step S107 uses the same map as in step S106. However, the threshold used is the second threshold Nr2, which switches from the second mode to the first mode. Using this calculation result, it is determined whether the second mode should be maintained (step S113). If it is determined that it should not be maintained (No), the system performs a switch control to the first mode operation (step S114). If it is determined that it should be maintained (Yes), it is determined whether the mode switching control is in progress (step S115). If the switching control is in progress (Yes), the system maintains the second mode until the switch is complete. If the switching control is not being performed (No), the system continues in the second mode (step S117).

[0121] Once the above judgment and control are completed (step S118), control is restarted (step S100), and this flow is repeated at regular intervals. Note that in Figure 18, the line that loops from end (S118) to start (S100) is not shown. This is because, in addition to this switching control between the first and second modes, there are many other controls, such as the control of the internal combustion engine 100 and the control for diagnosing faults in various equipment, and the overall control loop is a larger loop that includes these other controls.

[0122] Next, the switching control to the second mode in step S109 will be explained based on Figure 19. The switching control starts from step S130. First, the rotation direction of the rotor 210 of the rotating electric machine 200 is determined (step S131). If the rotation in the first direction, which is the rotation direction in the first mode, is maintained, it is determined whether the rotation speed is equal to or greater than the first rotation speed (step S132). If it is equal to or greater than the first rotation speed (Yes), brake control is performed (step S133) to reduce the rotation speed in the first direction. If it is determined in step S132 that the rotation speed in the first direction is less than the first rotation speed (No), phase inversion control is used to reduce the rotation speed in the first direction (step S134).

[0123] As a result of brake control (S133) and phase inversion control (S134), if rotation in the second direction is determined in step S131, the state of the first one-way clutch 610 and the second one-way clutch 620 is determined (step S135). This determination of the state of the one-way clutch (step S135) will be explained using the flowchart in Figure 23. Figure 23 is also the flowchart for the vehicle state detection step S101. It acquires information used for the overall control of the rotating electric machine 200, such as the accelerator opening and the speed of the drive wheels 120. The information acquired also includes the one-way clutch state determination step S135. When the flow in Figure 23 is started (step S150), the accelerator opening is detected (step S151), the rotational speed of the drive shaft 130 is detected (step S152), and the rotational speed of the rotor 210 of the rotating electric machine 200 is detected (step S153). Based on this information, the system calculates whether the inner ring 630 and outer ring 631 of the first one-way clutch 610 are engaged or free-spinning, and the rotational speeds of the inner ring 630 and outer ring 631 (step S154). Similarly, based on the accelerator opening, the rotational speed of the drive shaft 130, and the rotational speed of the rotor 210, the system calculates the rotational speeds of the inner ring 630 and outer ring 631 of the second one-way clutch 620 (step S155).

[0124] Then, from the state of the first one-way clutch 610 calculated in step S154 and the state of the second one-way clutch 620 calculated in step S155, the rotational speed deviation between the inner ring 630 and the outer ring 631 of either one-way clutch 610 or 620 is calculated (step S155). As described above, when switching from the first mode to the second mode, the rotational speed deviation between the inner ring 630 and the outer ring 631 of the second one-way clutch 620 is calculated. This allows for the calculation of the second rotational speed n4 at which the second one-way clutch 620 engages, and the third rotational speed n3 which is a predetermined number of rotations less than that speed. Also, when switching from the second mode to the first mode, the rotational speed deviation between the inner ring 630 and the outer ring 631 of the first one-way clutch 610 is calculated. Once these rotational speeds can be calculated, the one-way clutch state determination flow is completed (step S157).

[0125] Returning to the flowchart in Figure 19, if the rotational speed is less than the third rotational speed n3 in the one-way clutch state determination (step S135), the control device 250 rotates the rotor 210 of the rotating electric machine 200 in the second direction with the first duty cycle d1 (step S136). In this state, the second one-way clutch 620 is still free-spinning, so the rotational speed in the second direction is increased early. If the rotational speed in the second direction is greater than the third rotational speed n3 and is less than or equal to the second rotational speed n4, the control device 250 rotates the rotor 210 of the rotating electric machine 200 in the second direction with the second duty cycle d2. In this state, the second one-way clutch 620 is about to engage. As described above, the second duty cycle d2 is smaller than the first duty cycle d1, and the control prepares for the engagement of the second one-way clutch 620. If the rotational speed is greater than the second rotational speed n4, the machine has already entered the second mode, so the drive control for the second mode is performed (step S138).

[0126] After performing one of the above brake control (step S133), phase inversion control (step S134), first duty cycle control (step S136), second duty cycle control (step S137), or second mode drive control (step S138), the control loop is closed (step S139). If the brake control (step S133), phase inversion control (step S134), first duty cycle control (step S136), or second duty cycle control (step S137) is performed, the system returns to start (step S135) and continues the switching control to the second mode in step S109. If the system enters second mode drive control (step S138), the control device starts the control flow loop for the second mode.

[0127] Figure 20 shows the control flowchart for the switching control to the first mode (step S114) in step S114. Switching from the first mode to the second mode is when the rotation direction of the rotor 210 of the rotating electric machine 200 is changed from the first direction to the second direction. In contrast, switching from the second mode to the first mode is when the rotation direction of the rotor 210 of the rotating electric machine 200 is changed from the second direction to the first direction. This is the control that occurs when decelerating in the two-wheeled vehicle 10, and the rotation speed of the drive shaft 130 is reversed. That is, switching from the first mode to the second mode is done while increasing the speed of the drive shaft 130. In contrast, switching from the second mode to the first mode is done when decreasing the rotation speed of the drive shaft 130.

[0128] However, from the perspective of controlling the rotation of the rotor 210 of the rotating electric machine 200, the flowcharts for both control methods are generally the same. Therefore, in the switching control from the first mode to the second mode shown in Figure 19, the steps explained in the 130s are omitted from the explanation in the switching control from the second mode to the first mode shown in Figure 20, by assigning the corresponding steps in the 150s.

[0129] In this disclosure, whether switching from the first mode to the second mode or from the second mode to the first mode, the switching control first performs brake control (steps S133, S153) to gradually reduce the rotational speed of the rotor 210 of the rotating electric machine 200. Next, phase inversion control (steps S134, S154) is performed. In the example above, the duty cycle is set to 100 percent to reduce the speed early. Note that when switching from the first mode to the second mode, the first direction becomes one direction and the second direction becomes the other direction. When switching from the second mode to the first mode, conversely, the second direction becomes one direction and the first direction becomes the other direction.

[0130] When the rotation direction is reversed by phase inversion control (steps S134, S154), control is switched to the first duty cycle d1 (steps S136, S156). In the example above, the duty cycle is maintained at 100 percent. When the rotation speed in the reversed direction increases to the third rotation speed n3, control is switched to the second duty cycle d2 (steps S137, S157). This protects the one-way clutches 610 and 620 on the side that is engaged. When the rotation speed in the reversed direction reaches the second rotation speed n4, either the one-way clutch 610 or 620 engages, and the switching of the operating mode is completed.

[0131] The above is a preferred example of this disclosure, but this disclosure is subject to various modifications. In the above example, the brake control (steps S133, S153) is the electromagnetic brake control shown in Figure 15. That is, by turning off the U-phase semiconductor switch 3511, the V-phase semiconductor switch 3512, and the W-phase semiconductor switch 3513, the power supply to the U-phase coil 353, V-phase coil 354, and W-phase coil 355 of the rotating electric machine 200 is cut off. It is also possible to perform electromagnetic brake control by turning off the low-voltage U-phase semiconductor switch 3521, the low-voltage V-phase semiconductor switch 3522, and the low-voltage W-phase semiconductor switch 3523 located on the low-voltage side wiring 3520, thereby preventing power supply. Furthermore, it is also possible to use regenerative brake control instead of electromagnetic brake control. Regenerative braking control is a control method that uses the rotational energy of the rotating electric machine 200 for power generation by switching the U-phase semiconductor switch 3511, V-phase semiconductor switch 3512, and W-phase semiconductor switch 3513 located on the high-voltage side wiring 3510, and the low-voltage U-phase semiconductor switch 3521, low-voltage V-phase semiconductor switch 3522, and low-voltage W-phase semiconductor switch 352 located on the low-voltage side wiring 3520. By using regenerative braking control, it is also possible to use the rotating electric machine 200 for energy recovery.

[0132] In brake control, it's difficult to definitively say whether electromagnetic brake control or regenerative brake control is stronger, but electromagnetic brake control provides more stable braking force. This is because, as mentioned above, electromagnetic brake control consumes all of the rotational energy of the rotating electric machine 200 as heat energy through electrical resistance. Therefore, the current flowing according to the electrical resistance value is converted into the torque that generates the braking force. On the other hand, regenerative brake control also converts the rotational energy of the rotating electric machine 200 into electrical energy, but this electrical energy is stored in the battery 351. Here, in order to store energy, an induced voltage higher than the voltage of the battery 351 must be generated by the rotation of the rotating electric machine 200. Therefore, the amount of current that can flow depends on the charge state of the battery 351. Considering the protection and lifespan of the battery 351, it may be necessary to limit the regenerated electrical energy to prevent overcharging.

[0133] Furthermore, in the above example, the phase inversion control (steps S134, S154) set the duty cycle to 100 percent. This is desirable as it allows for early deceleration. However, the duty cycle control can also be adjusted, as shown in Figure 26, starting from a duty cycle d3 that maintains the first rotational speed n2, and gradually increasing the duty cycle. Adopting this control can help protect the mechanical components.

[0134] Furthermore, in the above example, as shown in Figure 17, the duty cycle was maintained at 100 percent during control at the first duty cycle d1 (steps S136, S156). If this were changed to the phase inversion control (steps S134, S154) which gradually increases the duty cycle, this control could be continued in conjunction with that. In the example in Figure 26, the duty cycle is set to 100 percent before the rotation of the rotor 210 of the rotating electric machine 200 becomes zero. However, it is also possible to have a control where the duty cycle has not yet reached 100 percent when the rotation of the rotating electric machine 200 becomes zero. In that case, the duty cycle at the point when the rotation speed of the rotor 210 of the rotating electric machine 200 becomes zero in the phase inversion control (steps S134, S154) can be used as the starting point, and the duty cycle can be continuously gradually increased in the control at the first duty cycle (steps S136, S156). Conversely, as in the example in Figure 26, if the control is set so that the duty cycle becomes 100 percent before the rotation of the electric rotating machine 200 becomes zero, it is also possible to set the first duty cycle d1 to a predetermined value less than 100 percent, rather than 100 percent.

[0135] Furthermore, in the example described above, the duty cycle was reduced by control at the second duty cycle d2 (steps S137, S157). This is desirable control as it protects the one-way clutches 610 and 620 on the meshing side. However, control at the second duty cycle (steps S137, S157) is not essential. It can be omitted if the switching between the first and second modes is performed early. By omitting control at the second duty cycle (steps S137, S157), the memory (ROM) capacity of the control device 250 and the load on the arithmetic unit (CPU) can be reduced. Also, if the first duty cycle is not 100 percent, it is considered that omitting control at the second duty cycle (steps S137, S157) will not have a significant impact on the one-way clutches 610 and 620 on the meshing side.

[0136] Furthermore, in the above example, the control of the present disclosure was applied to the hybrid drive unit 1. Not only the first and second modes, but also the third and fourth modes can be performed, which is a desirable example. However, the control device of the present disclosure can also be applied to an electric drive unit. Figure 24 shows the configuration of the electric drive unit 1000. The battery 351 and control device 250 are the same. The rotating electric machine 200 also rotates in the first and second directions. Furthermore, it is also the case that a speed-increasing transmission mechanism 1010 is provided that increases the speed of the rotation of the rotating electric machine 200 in the second direction compared to the rotation of the rotating electric machine 200 in the first direction and transmits it as rotation in the propulsion direction of the drive shaft 130. In Figure 24, the one-way clutch mechanism 600 is not shown, but the speed-increasing transmission mechanism 1010 uses the one-way clutch mechanism 600.

[0137] However, the planetary gear mechanism 500 is not essential. It is sufficient that the speed in the second direction can be increased compared to the first direction, and as shown in Figure 25, gears with different gear ratios in the first and second directions may be used. In the example in Figure 25, the rotating electric machine 200 rotates the second drive shaft 1300 in the first and second directions. The rotation of the second drive shaft 1300 in the first direction is transmitted to the first drive gear 710 via the first one-way clutch 610. The first drive gear 710 is supported coaxially with the second drive shaft 1300 by the first gear bearing 711. Similarly, the rotation of the second drive shaft 1300 in the second direction is transmitted to the second drive gear 720 via the second one-way clutch 620. The second drive gear 720 is also supported coaxially with the second drive shaft 1300 by the second gear bearing 721.

[0138] When the second drive shaft 1300 rotates in the first direction, only the first drive gear 710 rotates in the first direction. In this case, the second drive gear 720 does not rotate because the second one-way clutch 620 is free-spinning. The rotation of the first drive gear 710 in the first direction rotates the drive shaft 130 via the first driven gear 712. Note that the clockwise rotation of the first drive gear 710 results in the counterclockwise rotation of the first driven gear 712 and the drive shaft 130, but in this example, regardless of whether it is clockwise or counterclockwise, the direction in which the drive shaft 130 rotates in the first direction is defined as the first direction of rotation.

[0139] When the second drive shaft 1300 rotates in the second direction, the first one-way clutch 610 slips, and the first drive gear 710 does not rotate. The rotation in the second direction is transmitted to the second drive gear 720 by the engagement of the second one-way clutch 620. The rotation of the second drive gear 720 in the second direction causes the second driven gear 723 to rotate in the second direction via the idler gear 722. As with the first drive gear 710 described above, in this example, the second direction of rotation is defined not as clockwise or counterclockwise, but as the direction in which the drive shaft 130 rotates in the second direction.

[0140] The first drive gear 710 does not have an idler gear, and only the second drive gear 720 has an idler gear 722, which allows the rotation direction of the second drive shaft 1300 and the drive shaft 130 to be switched between the first and second directions. Furthermore, in the second direction, because the idler gear 722 is interposed, the speed can be increased compared to the rotation in the first direction. More specifically, the number of teeth of the first drive gear 710 is less than the number of teeth of the first driven gear 712. Therefore, the rotation of the second drive shaft 1300 in the first direction is transmitted to the drive shaft 130 at a predetermined reduction ratio. In contrast, because the idler gear 722 is interposed, the second drive gear 720 and the second driven gear 723 have the same number of teeth. As a result, the rotation of the second drive shaft 1300 in the second direction is transmitted as the rotation of the drive shaft 130 in the second direction without reduction.

[0141] Furthermore, the materials and sizes of the parts described in the above example can be changed as appropriate. The rotating electric machine 200 does not need to be three-phase AC; it may be single-phase or two-phase. A brushless motor can also be used. The necessary configuration for the rotating electric machine 200 is a closed circuit including a coil 224, which generates an induced voltage and allows current to flow. In addition, although the above example showed the use of the hybrid drive unit 1 and the electric drive unit 1000 in a motorcycle 10, the applications of the hybrid drive unit 1 and the electric drive unit 1000 of this disclosure are not limited to motorcycles 10. For example, they can be used in other equipment such as motorboats, snowmobiles, and tractors. Therefore, the drive wheel 120 is just one example of a drive unit, and this disclosure can be applied to drive units other than tires.

[0142] (Disclosure of technical ideas) This specification discloses several technical concepts, as listed in the following paragraphs. Some paragraphs are written in a multiple dependent form, where subsequent paragraphs optionally refer to preceding paragraphs. Furthermore, some paragraphs are written in a multiple dependent form, referring to other multiple dependent forms. These paragraphs written in multiple dependent forms define several technical concepts.

[0143] (Technical thought 1) A rotating electric machine comprising a rotor capable of transmitting rotation to a drive shaft that transmits driving force to a drive unit, with multiple permanent magnets arranged in the circumferential direction, and a stator fixed to a fixed cover and having multiple coils facing the permanent magnets, A battery that is electrically connected to this rotating electric machine, A control device is electrically connected to this battery and the rotating electric machine, and controls the switching between rotation in a first direction and rotation in a second direction opposite to the first direction of the rotating electric machine, as well as controlling the rotational speed in the first direction and the rotational speed in the second direction. Interposed between the rotating electric machine and the drive shaft, the system includes a first one-way clutch that transmits rotation only in the first direction and a second one-way clutch that transmits rotation only in the second direction, thereby transmitting both the rotation of the rotating electric machine in the first direction and the rotation of the rotating electric machine in the second direction as rotation in the propulsion direction of the drive shaft, and also includes a speed-increasing transmission mechanism that increases the speed of the rotation of the rotating electric machine in the second direction compared to the rotation of the rotating electric machine in the first direction and transmits it as rotation in the propulsion direction of the drive shaft, When the control device performs rotation direction reversal control to switch the rotation of the rotating electric machine from one of the first and second directions to the other direction, it performs brake control when the rotation speed in one direction is equal to or greater than a predetermined first rotation speed, and performs phase reversal control to change the rotation direction of the rotating electric machine to the other direction when the rotation speed in one direction falls below the predetermined first rotation speed. A drive force control device characterized by the following:

[0144] (Technical thought 2) When the control device switches the rotation of the rotating electric machine from one direction to the other direction, it controls the rotation of the other direction with a first duty cycle when the rotational speed in the other direction is less than a third rotational speed which is a predetermined number of rotational speeds less than a predetermined second rotational speed, and controls the rotation of the other direction with a second duty cycle when the rotational speed in the other direction is between the third rotational speed and the second rotational speed, wherein the second duty cycle is smaller than the first duty cycle, and the second rotational speed is the rotational speed at which either the first one-way clutch or the second one-way clutch begins to transmit the rotation in the other direction. A drive force control device according to the technical concept 1, characterized by the above.

[0145] (Technical Thought 3) The control device performs the phase inversion control with a duty cycle of 100 percent. A drive force control device according to technical concept 1 or 2, characterized by the above.

[0146] (Technical Thought 4) The control device performs the phase inversion control by increasing the duty cycle in accordance with the decrease in the rotational speed in the first direction. A drive force control device according to technical concept 1 or 2, characterized by the above.

[0147] (Technical Thought 5) The control device performs the brake control by electromagnetic brake control that disconnects the electrical connection between all the coils and the battery. A drive force control device according to any one of the technical ideas 1 to 4, characterized by the above.

[0148] (Technical Thought 6) The control device performs the brake control using regenerative braking control, which generates electricity using the rotating electric machine. A drive force control device according to any one of the technical ideas 1 to 4, characterized by the above.

[0149] (Technical Thought 7) The aforementioned rotating electric machine is a vehicle drive system, The control device switches between rotation in the first direction and rotation in the second direction according to the actual speed and required speed of the vehicle, and provides a predetermined hysteresis for switching from rotation in the first direction to rotation in the second direction and from rotation in the second direction to rotation in the first direction. A drive force control device according to any one of the technical ideas 1 to 6, characterized by the above.

[0150] (Technical Thought 8) The aforementioned hysteresis is greater in the high-load region than in the low-load region. A drive force control device according to the technical concept 7, characterized by the features described above. [Explanation of Symbols]

[0151] 10 Motorcycles 200 Rotating Electric Machine 250 Control devices 600 One-way clutch mechanism n2 First rotation speed n3 Third rotation speed n4 Second rotation speed S133 Brake Control S134 Phase Inversion Control

Claims

1. A rotating electric machine comprising a rotor capable of transmitting rotation to a drive shaft that transmits driving force to a drive unit, with multiple permanent magnets arranged in the circumferential direction, and a stator fixed to a fixed cover and having multiple coils facing the permanent magnets, A battery that is electrically connected to this rotating electric machine, A control device is electrically connected to this battery and the rotating electric machine, and controls the switching between rotation in a first direction and rotation in a second direction opposite to the first direction of the rotating electric machine, as well as controlling the rotational speed in the first direction and the rotational speed in the second direction. Interposed between the rotating electric machine and the drive shaft, the system includes a first one-way clutch that transmits rotation only in the first direction and a second one-way clutch that transmits rotation only in the second direction, thereby transmitting both the rotation of the rotating electric machine in the first direction and the rotation of the rotating electric machine in the second direction as rotation in the propulsion direction of the drive shaft, and also includes a speed-increasing transmission mechanism that increases the speed of the rotation of the rotating electric machine in the second direction compared to the rotation of the rotating electric machine in the first direction and transmits it as rotation in the propulsion direction of the drive shaft, When the control device performs rotation direction reversal control to switch the rotation of the rotating electric machine from one of the first and second directions to the other direction, it performs brake control when the rotation speed in one direction is equal to or greater than a predetermined first rotation speed, and performs phase reversal control to change the rotation direction of the rotating electric machine to the other direction when the rotation speed in one direction falls below the predetermined first rotation speed. A drive force control device characterized by the following:

2. When the control device switches the rotation of the rotating electric machine from one direction to the other direction, it controls the rotation of the other direction with a first duty cycle when the rotational speed in the other direction is less than a third rotational speed which is a predetermined number of rotational speeds less than a predetermined second rotational speed, and controls the rotation of the other direction with a second duty cycle when the rotational speed in the other direction is between the third rotational speed and the second rotational speed, wherein the second duty cycle is smaller than the first duty cycle, and the second rotational speed is the rotational speed at which either the first one-way clutch or the second one-way clutch begins to transmit the rotation in the other direction. The drive force control device according to feature 1.

3. The control device performs the phase inversion control with a duty cycle of 100 percent. The drive force control device according to claim 1 or 2.

4. The control device performs the phase inversion control by increasing the duty cycle in accordance with the decrease in the rotational speed in the first direction. The drive force control device according to claim 1 or 2.

5. The control device performs the brake control by electromagnetic brake control that disconnects the electrical connection between all the coils and the battery. The drive force control device according to claim 1 or 2.

6. The control device performs the brake control using regenerative braking control, which generates electricity using the rotating electric machine. The drive force control device according to claim 1 or 2.

7. The aforementioned rotating electric machine is a vehicle drive system, The control device switches between rotation in the first direction and rotation in the second direction according to the actual speed and required speed of the vehicle, and provides a predetermined hysteresis for switching from rotation in the first direction to rotation in the second direction and from rotation in the second direction to rotation in the first direction. The drive force control device according to claim 1 or 2.

8. The aforementioned hysteresis is greater in the high-load region than in the low-load region. The drive force control device according to feature 7.

Images