Hybrid drive unit and auxiliary power unit using an internal combustion engine and a rotating electric machine

Abstract

To provide a hybrid drive device using an internal combustion engine and a rotary electric machine, without adding a special actuator or the like thereto.SOLUTION: The hybrid drive device is provided with a centrifugal clutch mechanism configured so that when a rotation speed of an internal combustion engine is above a predetermined speed, driving force of the internal combustion engine is transmitted to a centrifugal clutch rotor 420, and a one-way clutch, interposed between a rotor of a rotary electric machine and the centrifugal clutch rotor, which transmits rotation in a first direction of the rotor to the centrifugal clutch rotor but does not transmit rotation in the first direction of the centrifugal clutch rotor to the rotor. In a second mode in which rotation of the rotary electric machine is unused and a driving shaft is rotated by driving force of the internal combustion engine, rotation of the internal combustion engine is transmitted from the centrifugal clutch rotor to the driving shaft. In the second mode, rotation of the centrifugal clutch rotor is blocked by the one-way clutch and therefore is not transmitted to the rotor, and rotation of the rotor is stopped by rotation suppression torque generated by suctioning of a permanent magnet into a stator.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The description in this specification relates to a hybrid drive unit and an auxiliary power unit that use an internal combustion engine and a rotating electric machine, and is useful for use as a drive unit or auxiliary power unit for a motorcycle, for example. [Background technology]

[0002] Hybrid drive systems that use an internal combustion engine and a rotating electric machine are known as drive systems for motorcycles. In such hybrid drive systems, the rotating electric machine rotates even when the vehicle is running using only the internal combustion engine, which raises concerns about friction loss due to magnetic resistance of the rotating electric machine. Therefore, mechanisms for reducing this magnetic friction loss are disclosed in Patent Documents 1 and 2. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-271040 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-99246 Summary of the Invention [Problem to be solved by the invention]

[0004] The hybrid drive device described in Patent Document 1 is provided with an adjustment mechanism that adjusts the magnetic field generated by the permanent magnets of the rotating electric machine, thereby adjusting the torque of the rotating electric machine. Also, the hybrid drive device described in Patent Document 2 uses a gap adjuster to adjust the gap between the rotor and stator of the rotating electric machine.

[0005] However, both of these methods required mechanical movement space for adjustment. Furthermore, they all used actuators for adjustment, which made the mechanisms and configurations complicated. Furthermore, they required space to install the actuators, and a controller to control the actuators.

[0006] An object of the present disclosure is to achieve a hybrid drive device that uses an internal combustion engine and a rotating electric machine without adding a special actuator or the like to the rotating electric machine and a controller that controls this actuator or the like.

[0007] Another object of the present disclosure is to provide an auxiliary power unit that can assist in driving an internal combustion engine by incorporating a rotating electric machine that does not require the addition of special actuators, etc. and a controller that controls these actuators, etc., to a drive unit that was previously driven solely by an internal combustion engine. [Means for solving the problem]

[0008] A first aspect of the present disclosure is a drive device including an internal combustion engine and a drive shaft that can rotate by receiving driving force from the internal combustion engine and transmits the driving force to a drive unit. The first aspect of the present disclosure also includes a rotating electric machine that includes a rotor that has a plurality of permanent magnets arranged in the circumferential direction and can rotate coaxially with the drive shaft, and a stator that is fixed to a fixed cover and has a plurality of coils that face the permanent magnets, a battery that is electrically connected to the rotating electric machine, and a control device that is electrically connected to the battery and the rotating electric machine and controls the rotation of the rotating electric machine. The first aspect of the present disclosure is a hybrid drive device using an internal combustion engine and a rotating electric machine, which includes a centrifugal clutch mechanism in which the driving force of the internal combustion engine is not transmitted to the centrifugal clutch rotor when the rotation speed of the internal combustion engine is below a predetermined number, and in which the driving force of the internal combustion engine is transmitted to the centrifugal clutch rotor when the rotation speed of the internal combustion engine is equal to or greater than the predetermined number, and a one-way clutch interposed between the rotor of the rotating electric machine and the centrifugal clutch rotor, which transmits rotation of the rotor in a first direction to the centrifugal clutch rotor, does not transmit rotation of the rotor in a second direction which is opposite to the first direction to the centrifugal clutch rotor, and does not transmit rotation of the centrifugal clutch rotor in the first direction to the rotor.

[0009] In the first aspect of the present disclosure, the one-way clutch prevents the rotation of the centrifugal clutch rotor in the first direction from being transmitted to the rotor, so that when the driving force of only the internal combustion engine is used and the driving force of the rotating electric machine is not used, it is possible to stop the rotating electric machine.There is no relative rotation between the rotor and the stator, This eliminates the need to install a special actuator for suppressing friction loss due to magnetic resistance of the rotating electrical machine.

[0010] A second aspect of the present disclosure further includes a second rotating electric machine driven by the internal combustion engine. The rotating electric machine is used as a drive motor for the drive shaft, and the second rotating electric machine is used as a starter for starting the internal combustion engine and a generator for charging the battery. Even a drive device that uses only an internal combustion engine is provided with the second rotating electric machine used as a starter and a generator for charging the battery. Therefore, in the second aspect of the present disclosure, the rotating electric machine can be used only as a drive motor for the drive shaft. This enables optimal design of a hybrid drive device using an internal combustion engine and a rotating electric machine.

[0011] A third aspect of the present disclosure is an auxiliary power unit used in a power unit that includes a drive shaft that is rotatable by receiving the driving force of an internal combustion engine and transmits the driving force to a drive section, and a centrifugal clutch mechanism that has a centrifugal clutch rotor and does not transmit the driving force of the internal combustion engine to the drive shaft when the rotation speed of the internal combustion engine is less than a predetermined number, and transmits the driving force of the internal combustion engine to the drive shaft when the rotation speed of the internal combustion engine is equal to or greater than the predetermined number.

[0012] A third auxiliary power unit of the present disclosure includes a rotating electric machine including a rotor with a plurality of permanent magnets arranged circumferentially and rotatable coaxially with a drive shaft, and a stator fixed to a fixed cover and having a plurality of coils facing the permanent magnets, and a control device that controls the rotation of the rotating electric machine.The unit also includes a one-way clutch interposed between the rotor of the rotating electric machine and a centrifugal clutch rotor, which transmits rotation of the rotor in a first direction to the centrifugal clutch rotor, does not transmit rotation of the rotor in a second direction opposite to the first direction to the centrifugal clutch rotor, and does not transmit rotation of the centrifugal clutch rotor in the first direction to the rotor.

[0013] In the third aspect of the present disclosure, as in the first aspect, the one-way clutch prevents the rotation of the centrifugal clutch rotor in the first direction from being transmitted to the rotor. Therefore, when only the driving force of the internal combustion engine is used and the driving force of the rotating electric machine is not used, it is possible to stop the rotating electric machine. As a result, in the first aspect of the present disclosure, There is no relative rotation between the rotor and the stator, This eliminates the need to install a special actuator for suppressing friction loss due to magnetic resistance of the rotating electrical machine.

[0014] A fourth aspect of the present disclosure is a vehicle equipped with a second one-way clutch interposed between the centrifugal clutch rotor and the drive shaft. The second one-way clutch transmits the rotation of the centrifugal clutch rotor in a first direction to the drive shaft, but does not transmit the rotation of the drive shaft in the first direction to the centrifugal clutch rotor. The second direction rotation of the drive shaft, which is the reverse direction, is transmitted to the centrifugal clutch rotor. Therefore, when the vehicle is driven by the internal combustion engine, even if the engine speed is reduced, the moment of inertia from the drive shaft is not applied to the internal combustion engine. This means that, while engine braking is no longer effective, the vehicle can travel by coasting, enabling smooth operation of the internal combustion engine.

[0015] In the fifth aspect of the present disclosure, the centrifugal clutch rotor and the drive shaft are coupled together to rotate as a unit, which is the opposite of the fourth aspect. When the rotation speed of the centrifugal clutch mechanism driven pulley 410 exceeds the rotation speed of the drive shaft while the vehicle is running on the internal combustion engine (P108), the rotation speed of the internal combustion engine is reduced in the coupled state, making it possible to utilize engine braking.

[0016] In a sixth aspect of the present disclosure, a one-way cam clutch having a one-way clutch cam between an inner ring and an outer ring is used as the one-way clutch. By using a one-way cam clutch, the sliding resistance of the one-way clutch can be further reduced. Therefore, when only the driving force of the internal combustion engine is used and the driving force of the rotating electric machine is not used, it is possible to more reliably stop the rotating electric machine.

[0017] In a seventh aspect of the present disclosure, in a first mode in which the drive shaft starts to rotate in a first direction, the rotor of the rotating electric machine is rotated in the first direction, and the rotation of the rotor is transmitted to the drive shaft via the one-way clutch and the centrifugal clutch rotor. In the seventh aspect of the present disclosure, motor running by the rotating electric machine is possible at start-up.

[0018] In the eighth aspect of the present disclosure, in a second mode in which the drive shaft rotates steadily in the first direction at a predetermined rotation speed or more, the rotation of the rotor of the rotating electric machine is stopped, and the rotation of the internal combustion engine is transmitted to the drive shaft via the centrifugal clutch rotor. In the eighth aspect of the present disclosure, steady running by the internal combustion engine is possible. During this steady running, the rotation of the centrifugal clutch rotor is not transmitted to the rotating electric machine by the one-way clutch. As described above, when the driving force of the rotating electric machine is not used, the rotating electric machine can be stopped.

[0019] In a ninth mode of the present disclosure, in a third mode in which the rotation speed of the drive shaft is further increased from a state in which the drive shaft rotates in the first direction at a predetermined rotation speed or more, the rotation of the internal combustion engine is transmitted to the drive shaft via the centrifugal clutch rotor, and the rotor of the rotating electric machine is rotated in the first direction, and the rotation of the rotor is also transmitted to the drive shaft via the one-way clutch and the centrifugal clutch rotor. In the ninth mode of the present disclosure, in addition to steady running by the internal combustion engine, assisted running by the rotating electric machine is also possible. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a system configuration diagram of a hybrid drive system. [Figure 2] FIG. 2 is a perspective view showing the main configuration of the hybrid drive device. [Figure 3] FIG. 3 is a configuration diagram of the hybrid drive system shown in FIG. [Figure 4] FIG. 4 is a side view of a motorcycle equipped with a hybrid drive unit. [Figure 5] FIG. 5 is a rear view of a motorcycle equipped with a hybrid drive unit. [Figure 6] FIG. 6 is a front view showing the state of the centrifugal clutch when stopped. [Figure 7] FIG. 7 is a front view showing the state of the centrifugal clutch during rotation. [Figure 8] FIG. 8 is a perspective view showing a rotating electric machine. [Figure 9] FIG. 9 is a perspective view of the device shown in FIG. 8 with the rotor removed. [Figure 10] FIG. 10 is a front view showing the state of the one-way clutch when engaged. [Figure 11] FIG. 11 is a front view showing the state of the one-way clutch during idling. [Figure 12] FIG. 12 is a diagram for explaining the state of a rotating electrical machine or the like in each mode. [Figure 13] FIG. 13 is a configuration diagram showing another example of a hybrid drive device. [Figure 14] FIG. 14 is a configuration diagram showing still another example of a hybrid drive device. [Figure 15] FIG. 15 is a diagram showing the configuration of another example of a one-way clutch during idling. [Figure 16] FIG. 16 is a diagram showing another example of the one-way clutch in another idling state. [Figure 17] FIG. 17 is a diagram showing the configuration of another example of a one-way clutch in an engaged state. DETAILED DESCRIPTION OF THE INVENTION

[0021] An example of the present disclosure will be described below with reference to the drawings. Fig. 1 shows an overview of the system configuration of a hybrid drive system 1. The hybrid drive system 1 includes an internal combustion engine 100 and a rotating electric machine 200. The hybrid drive system of Fig. 1 also includes 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 receives driving force from the internal combustion engine 100 to generate electricity. Therefore, the rotating electric machine 200 can be used exclusively as an auxiliary power unit.

[0022] The three-phase AC current generated by the second rotating electric machine 300 is converted into DC 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 DC current from the battery 351 into three-phase AC current.

[0023] The direct current from the battery 351 is also supplied to the rotating electric machine 200. The rotation of the rotating electric machine 200 is controlled by the control device 250. The control device 250 also converts the direct current into three-phase alternating current to control the rotation speed. The control device 250 can also control the rotation direction of the rotating electric machine 200. That is, the control device 250 can control the rotating electric machine 200 to rotate in a first direction (for example, forward rotation) and in a second direction (reverse rotation) opposite to the first direction. In this embodiment, the control device 250 performs braking control using the rotation in the second direction.

[0024] The hybrid drive system 1 also includes a centrifugal clutch mechanism 400, as shown in Fig. 2. When the rotation speed of the internal combustion engine 100 is less than a predetermined number, the centrifugal clutch mechanism 400 does not transmit the driving force of the internal combustion engine 100 to the centrifugal clutch rotor 420, and when the rotation speed of the internal combustion engine 100 is equal to or greater than the predetermined number, the centrifugal clutch mechanism 400 transmits the driving force of the internal combustion engine 100 to the centrifugal clutch rotor 420. The predetermined rotation 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 system 1 also includes a one-way clutch 600 disposed between the rotating electric machine 200 and the centrifugal clutch mechanism 400.

[0025] As shown in Fig. 2, the rotating electrical machine 200, one-way clutch 600, and centrifugal clutch mechanism 400 are arranged coaxially. Fig. 3 is a structural diagram that schematically shows each of these components, and as shown in Fig. 3, each component is arranged inside a fixed cover 150. The fixed cover 150 is made of aluminum or an aluminum alloy, but may also be made of resin. Examples of resin materials include fluororesin (PTFE, PFA), carbon fiber reinforced plastic (CFRP), polypropylene (PP), and polycarbonate (PC).

[0026] 4 and 5, the fixed cover 150 is fixed to the vehicle body facing the rear wheel of the two-wheeled vehicle 10. More specifically, it is disposed on the drive shaft 130 (shown in FIG. 3) side of the rear wheel. When the hybrid drive system of the present disclosure is used in the two-wheeled vehicle 10, the rear wheel becomes the drive wheel 120.

[0027] Each component will be described below. First, the centrifugal clutch mechanism 400 will be described. In the internal combustion engine 100, a piston 101 reciprocates within a cylinder 110, and the reciprocating motion of the piston 101 is transmitted to a crankshaft 104 via a connecting rod 102 and a web 103. The crankshaft 104 rotates while being supported by a bearing. The rotation of the crankshaft 104 is transmitted to a drive pulley 105. The rotation of the crankshaft 104 is also transmitted to a second rotating electric machine 300.

[0028] The rotation of the drive pulley 105 is transmitted to the centrifugal clutch mechanism 400 via the belt 106. As shown in FIG. 2, in the centrifugal clutch mechanism 400, the belt 106 is engaged with the driven pulley 410, and the driven pulley 410 rotates upon receiving the driving force of the belt 106. The driven pulley 410 is journaled on the drive shaft 130 by a centrifugal clutch bearing 440. Both the drive pulley 105 and the driven pulley 410 are made of metal, such as rolled steel plate, aluminum, or aluminum alloy.

[0029] As shown in Figures 6 and 7, the centrifugal clutch mechanism 400 has three centrifugal clutch shoes 411 journaled on a rotating shaft 412 and spaced apart 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, as shown in Figure 6, the centrifugal clutch shoes 411 are pulled radially inward by centrifugal clutch springs 415. The centrifugal clutch shoes 411 are made of aluminum or a metal such as aluminum or iron.

[0030] Figure 7 shows the state when centrifugal force is applied. When the centrifugal force acting on centrifugal clutch shoe 411 overcomes the tensile force of centrifugal clutch spring 415, centrifugal clutch shoe 411 comes into contact with the inner periphery of centrifugal clutch rotor 420. As shown in Figure 2, centrifugal clutch lining 413 is affixed to the outer periphery of centrifugal clutch shoe 411 to increase the frictional force with centrifugal clutch rotor 420. This centrifugal clutch lining 413 is made of a non-asbestos material.

[0031] Centrifugal clutch rotor 420 is supported via second one-way clutch 610 on drive shaft 130, which drives the rear wheel (drive wheel 120) of the motorcycle. More specifically, the rotation of drive shaft 130 is transmitted to drive wheel 120 via final gear 140 and tire shaft 141. Centrifugal clutch rotor 420 is integrally formed with a disk-shaped clutch base 421 that can rotate together with second one-way clutch 610, and a cylindrical clutch ring 422 that is disposed on the outer periphery of this clutch base 421.

[0032] When the internal combustion engine 100 is stopped or the rotation speed of the internal combustion engine 100 is low, the driven pulley 410 is also stopped or rotating at a low speed. In this state, the centrifugal clutch rotor 420 does not rotate, so the state shown in Figure 6 is maintained by the tension force of the centrifugal clutch spring 415.

[0033] When the rotation speed of the internal combustion engine 100 increases and the rotation speed of the driven pulley 410 exceeds a predetermined value, the centrifugal clutch shoe 411 rotates outward around the rotation shaft 412 due to centrifugal force. As a result, the centrifugal clutch shoe 411 comes into contact with the inner peripheral surface of the clutch ring 422. In particular, since the centrifugal clutch lining 413 is attached to the outer peripheral surface of the centrifugal clutch shoe 411, the frictional force between the centrifugal clutch shoe 411 and the clutch ring 422 is high. Therefore, the rotation of the driven pulley 410 is transmitted to the centrifugal clutch rotor 420, and the centrifugal clutch rotor 420 is supported by the drive shaft 130 and rotates.

[0034] Next, the rotating electric machine 200 will be described. As shown in FIG. 3, the rotating electric machine 200 is covered by a fixed cover 150. As described above, the fixed cover 150 is fixed to the vehicle body behind the internal combustion engine 100 of the motorcycle and 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 disposed on the fixed cover 150, and the tip of the drive shaft 130 is rotatably supported by this fixed cover bearing 151. A final gear 140 having a predetermined reduction ratio is disposed on 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 a tire shaft 141. Therefore, the rotation of the rotating electric machine 200 is reduced in speed by the final gear 140 and transmitted to the drive wheel 120. Therefore, even if a rotating electric machine 200 with a relatively small torque is used, the torque is increased by the final gear 140, and the two-wheeled vehicle 10 can start moving by overcoming the frictional resistance as the drive wheels 120 start to rotate.

[0035] The rotor 210 of the rotating electric machine 200 is rotatably supported on the drive shaft 130 by a rotor bearing 215. Therefore, the rotor 210 can rotate integrally with the drive shaft 130, or the drive shaft 130 or the rotor 210 can rotate independently. The rotor 210 is made of iron and includes a disk portion 217 extending radially outward from a base portion 216 supporting the rotor bearing 215, as shown in FIG. 3, and a cylindrical portion 211 formed radially outward of the disk portion 217. As shown in FIG. 8, twelve permanent magnets 212 are arranged circumferentially inside the cylindrical portion 211. The thickness of the permanent magnets 212 is approximately 2 to 5 millimeters. The number of permanent magnets 212 is not limited to 12, but can be set appropriately depending on the required performance, such as 20 or 24. Various types of permanent magnets 212 can be selected depending on the intended use. Strong rare earth magnets may be used, or inexpensive ferrite magnets may also be used.

[0036] As shown in Figures 3 and 8, a stator 220 is disposed inside the rotor 210. The stator 220 is made by laminating multiple magnetic steel plates, and integrally forms a base portion 221 attached to the fixed cover 150 and multiple teeth portions 222 extending radially outward from the base portion 221. The teeth portions 222 are electrically insulated by insulators made of insulating resin such as polyamide, and coils 224 made of copper wire or aluminum wire are wound on the insulators. Therefore, although only the tips of the teeth portions 222 are shown in Figure 9, they are also located in the areas where the coils 224 are wound.

[0037] 9 is a perspective view showing stator 220 and sensor case 230 with rotor 210 removed from FIG. 8. Although there are 18 teeth in FIGS. 8 and 9, the number of teeth can be set appropriately depending on the number of magnetic poles of rotor 210. The outer diameter of stator 220 is approximately 100 to 200 mm, and therefore the inner diameter of rotor 210 is sized to form a minute gap between the outer diameter of stator 220 and permanent magnet 212.

[0038] The base portion 221 has three stator bolt through-holes 223 for fixing the stator 220 to the fixed cover 150. The base portion 221 also has one sensor case bolt through-hole for fixing the sensor case 230 (described later) to the stator 220. However, the sensor case 230 can also be fixed to the fixed cover 150 instead of the stator 220. There may also be two or more sensor case bolt through-holes.

[0039] 9, gaps 225 are formed between adjacent coils 224, and these gaps 225 generally widen radially outward. However, to increase the space factor of the coils 224, the gaps may be kept substantially constant in the radial direction. The sensor case 230 also includes a sensor main body 231 and first through third Hall sensors 232-234 extending from the sensor main body 231 between adjacent coils 224. The first through third Hall sensors 232-234 are disposed in the gaps 225 between the adjacent coils 224.

[0040] Each of the Hall sensors 232-234 is approximately 2 mm x 3 mm in size, and is covered by a sensor case 230. Therefore, the figure shows not the actual Hall sensors 232-234, but the sheath of the sensor case 230 that houses the Hall sensors 232-234. The sensor main body 231 houses the sensor substrates of the Hall sensors 232-234, and is made of a resin material such as polyamide.

[0041] The first to third Hall sensors 232, 233, 234 face the permanent magnet 212, which is magnetized with alternating north and south poles, and detect the positions where the north and south poles alternate. The detection positions of the first to third Hall sensors 232, 233, 234 correspond to the energization periods of the V, W, and U phases, respectively, and when the rotating electric machine 200 is used as a motor to generate driving force, the supply of voltage to the coils 224 corresponding to the U, V, and W phases is controlled according to the detection positions. Note that the rotation angle sensors are not limited to the Hall sensors 232 to 235, and other angle sensors such as resolvers may also be used.

[0042] The second rotating electric machine 300 is also provided with similar Hall sensors 232-234, which are used as timing signals for controlling the currents 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 provided with a Hall sensor that detects the reference position of the internal combustion engine 100.

[0043] Next, the one-way clutch 600 will be described. The one-way clutch 600 and the second one-way clutch 610 have the same mechanism. The one-way clutch 600 is disposed between the disk portion 217 of the rotor 210 and the clutch ring 422 of the centrifugal clutch rotor 420. The second one-way clutch 610 is disposed between the clutch base 421 of the centrifugal clutch rotor 420 and the drive shaft 130.

[0044] As shown in FIGS. 10 and 11 , the one-way clutch 600 includes an inner ring 630 fixed to an inner peripheral member and an outer ring 631 fixed to an outer peripheral member. Both the inner ring 630 and the outer ring 631 are made of carbon steel. In the one-way clutch 600, the inner periphery of the inner ring 630 is fixed so as to fit with the outer periphery of the rotor ring portion 218 provided on the disk portion 217 of the rotor 210. The outer ring 631 of the one-way clutch 600 is fixed so as to fit with the inner periphery of the clutch ring 422 of the centrifugal clutch rotor 420. The central axes of the inner ring 630 and the outer ring 631 of the one-way clutch 600 coincide with the central axis of the drive shaft 130. However, because the power transmission direction of the one-way clutch 600 can be selected to be either forward or reverse, the outer ring 631 may be fitted with the rotor 210. In this case, the inner ring 630 would be fitted with the centrifugal clutch rotor 420.

[0045] In the second one-way clutch 610, the drive shaft 130 is fixed to pass through the inner peripheral ring 630, and the central axis of the inner peripheral ring 630 coincides with the central axis of the drive shaft 130. The outer peripheral ring 631 is fixed so that its outer periphery fits into the inner periphery of the clutch base 421 of the centrifugal clutch rotor 420. The central axis of the outer peripheral ring 631 also coincides with the central axis of the drive shaft 130.

[0046] An engagement wall 633 is formed on the inner peripheral ring 630, and the gap between this engagement wall 633 and the inner periphery of the outer peripheral ring 631 becomes smaller toward the outer peripheral ring 631. A cylindrical one-way clutch bar 632 is disposed between the engagement wall 633 and the inner periphery of the outer peripheral ring 631. The one-way clutch bar 632 is pressed toward the outer peripheral ring 631 by a one-way clutch spring 635 held in a holding hole 634 of the inner peripheral ring 630.

[0047] 10 shows the engaged state of the one-way clutch 600. In this example, the inner ring 630 is rotating clockwise, the outer ring 631 is rotating counterclockwise, or both. In other words, the relative rotation direction 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 rotation direction between the inner ring 630 and the outer ring 631, the one-way clutch bar 632 is engaged, and the inner ring 630 and the outer ring 631 rotate together.

[0048] Conversely, Figure 11 shows the one-way clutch 600 in an idling state. 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 between the inner ring 630 and the outer ring 631 is a direction that moves the one-way clutch bar 632 toward the inner ring 630. Depending on the relative rotation direction between the inner ring 630 and the outer ring 631, the one-way clutch bar 632 is separated, and the inner ring 630 and the outer ring 631 rotate freely or stop.

[0049] The engagement direction and idling direction of one-way clutch 600 can be set to either clockwise or counterclockwise by changing the orientation of engagement wall 633. One-way clutch 600 is configured to transmit rotation of the rotor in a first direction to centrifugal clutch rotor 420. Therefore, rotation of rotor 210 in a second direction is not transmitted to centrifugal clutch rotor 420. Similarly, rotation in the first direction from the centrifugal clutch rotor 420 side is not transmitted to rotor 210. In addition, second one-way clutch 610 is configured to transmit only rotation in the first direction (forward rotation) of centrifugal clutch rotor 420 to drive shaft 130, but not rotation in the second direction (reverse rotation).

[0050] Next, the operation of the hybrid drive system 1 configured as described above will be described. First, a first mode will be described in which the two-wheeled vehicle 10 is started using the driving force of the rotating electric machine 200 without using the driving force of the internal combustion engine 100. In this first mode, the internal combustion engine 100 is not rotating, so the driven pulley 410 is not rotating either, and the centrifugal clutch rotor 420 is free relative to the centrifugal clutch shoe 411. In the first mode, the control device 250 controls the supply of current to the U-phase, V-phase, and W-phase coils of the rotating electric machine 200 to rotate the rotor 210 in a first direction. Note that the first direction is the direction in which, when the drive shaft 130 rotates in the first direction, the drive wheels 120 rotate forward and the two-wheeled vehicle 10 moves forward (forward rotation direction).

[0051] At this time, since stator 220 is fixed to fixed cover 150, rotor 210 rotates in the first direction. Since inner ring 630 of one-way clutch 600 is fixed to rotor 210, inner ring 630 rotates in the first direction together with rotor 210. Since one-way clutch 600 is a mechanism that transmits the rotation of inner ring 630 in the first direction to outer ring 631, outer ring 631 also rotates in the first direction.

[0052] Since the outer ring 631 is fixed to the centrifugal clutch rotor 420, the centrifugal clutch rotor 420 also rotates in the first direction. The second one-way clutch 610 is configured so that when the centrifugal clutch rotor 420 rotates in the first direction, the outer ring 631 and the inner ring 630 mesh with each other via 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 second one-way clutch 610. Therefore, the rotational torque of the rotating electric machine 200 is transmitted directly to the drive shaft 130 via the one-way clutch 600, the centrifugal clutch rotor 420, and the second one-way clutch 610, and the drive shaft 130 rotates at the rotation speed of the rotating electric machine 200.

[0053] Next, a second mode will be described in which the rotating electric machine 200 does not rotate, and only the internal combustion engine 100 rotates. In this second 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. The rotation of this driven pulley 410 is transmitted to the centrifugal clutch shoe 411 via the rotating shaft 412, and centrifugal force is applied to the centrifugal clutch shoe 411. As a result, when the rotation speed of the rotating shaft 412 reaches or exceeds a predetermined rotation speed, the centrifugal clutch shoe 411 is pressed against the centrifugal clutch rotor 420 with sufficient pressing force, and the centrifugal clutch rotor 420 rotates together with the driven pulley 410. The rotation direction of this centrifugal clutch rotor 420 is the first direction.

[0054] 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 upon receiving the driving force from the belt 106, some torque fluctuation is applied to the centrifugal clutch rotor 420. However, the rotation in the first direction from the centrifugal clutch rotor 420 is blocked by the one-way clutch 600 and is not transmitted to the rotor 210. In other words, the transmission of rotation in the first direction by the one-way clutch 600 is only from the rotor 210 to the centrifugal clutch rotor 420, and is not transmitted from the centrifugal clutch rotor 420 to the rotor 210. In other words, when the centrifugal clutch rotor 420 rotates upon receiving the driving force of the internal combustion engine 100, the one-way clutch 600 rotates idly and the rotor 210 does not rotate. The running of the motorcycle 10 will be described later.

[0055] In the second mode, the rotating electric machine 200 is stopped, and the inner ring 630 of the one-way clutch 600 is also stopped. The mechanism of the one-way clutch 600 causes only the outer ring 631 to rotate in the first direction together with the centrifugal clutch rotor 420. This rotation of the centrifugal clutch rotor 420 in the first direction rotates the drive wheels 120 in the first direction (forward rotation) via the second one-way clutch 610.

[0056] 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 a steady operating state, the control device 250 does not perform braking (regeneration) control to suppress the rotation of the rotating electric machine 200.

[0057] That is, in the steady operating state, no current is applied to the coil of the rotating electric machine 200. As described above, in the steady operating state, the one-way clutch 600 rotates idly, and the rotor 210 does not rotate. Even if the rotation speed of the internal combustion engine 100 drops and the rotation speed of the drive shaft 130 increases, the rotation of the drive shaft 130 in the second direction is not transmitted by the second one-way clutch 610. Therefore, no force acts on the rotor 210 in the steady operating state. Even if a rotational torque is applied to the rotor 210 due to some torque fluctuation, the rotating electric machine 200 generates a torque that suppresses the rotation of the rotor 210 due to the attractive force of the permanent magnet 212, even in the de-energized state. Therefore, the rotor 210 is stopped by this rotation suppression torque from the permanent magnet 212. If the load torque of the drive wheels 120 increases while the rotor 210 is stopped, the rotation speed of the drive shaft 130 decreases.

[0058] However, because second one-way clutch 610 is interposed between them, the decrease in rotation speed of drive shaft 130 is not directly transmitted to centrifugal clutch rotor 420. Furthermore, even if the rotation speed of centrifugal clutch rotor 420 decreases, the rotation in the first direction of centrifugal clutch rotor 420 is blocked by the mechanism of one-way clutch 600 and is not transmitted to rotor 210.

[0059] Therefore, in the second mode, the rotor 210 does not rotate, and 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. Note that in this disclosure, magnetic friction loss refers to iron loss caused by 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.

[0060] Unlike the present disclosure, if the one-way clutch 600 mechanism is not provided, it is conceivable that the rotating electric machine 200 performs zero torque control by controlling the phase of the current flowing through the U-phase, V-phase, and W-phase in order to reduce friction loss in the rotating electric machine 200. However, even when zero torque control is performed, magnetic friction loss does not disappear. This magnetic friction loss results in a consumption of the output of the internal combustion engine 100, which is a factor that deteriorates the fuel efficiency of the internal combustion engine 100.

[0061] In contrast, in the present disclosure, there is no need to perform zero torque control, and no current is applied to the rotating electric machine 200. Therefore, the energy stored in the battery 351 is not wasted, and the opportunity for charging by the second rotating electric machine 300 can be reduced. As described above, since the rotating electric machine 200 does not rotate, no magnetic friction loss occurs. The one-way clutch 600 mechanism is used as a mechanism for suppressing this magnetic friction loss. Therefore, the present disclosure does not require a special actuator or the like for reducing magnetic friction loss, and a simple structure can be achieved.

[0062] Although some mechanical friction loss occurs due to the mechanism of the one-way clutch 600, this mechanical friction loss is extremely 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 device 1, the rotating electric machine 200 is not a major factor in reducing the fuel efficiency of the internal combustion engine 100. Since the rotating electric machine 200 is used as the hybrid drive device 1, an improvement in the fuel efficiency of the internal combustion engine 100 is expected.

[0063] Next, a third mode will be described, which utilizes the driving force of the rotary electric machine 200 in addition to the driving force of the internal combustion engine 100. Since this third mode is a continuation of the second mode, the driven pulley 410 is rotating, and the centrifugal clutch shoe 411 is also rotating together with the rotary shaft 412. Therefore, the centrifugal clutch shoe 411 is pressed against the centrifugal clutch rotor 420 by the centrifugal force caused by the rotation, and the centrifugal clutch rotor 420 is also rotating together with the driven pulley 410 in the first direction.

[0064] In the third mode, the control device 250 controls the supply of current to the U-phase, V-phase, and W-phase coils 224 of the rotating electric machine 200 to rotate the rotor 210 in the first direction. Therefore, as the rotating electric machine 200 rotates, a driving force in the first direction is applied from the rotor 210 to the drive shaft 130 via the centrifugal clutch rotor 420.

[0065] While the rotor 210 was stationary in the second mode, the rotor 210 rotates in the first direction in the third mode. When the rotation of the rotor 210 in the first direction becomes faster than the rotation of the centrifugal clutch rotor 420 in the first direction, the one-way clutch 600 engages, and the rotor 210 accelerates the centrifugal clutch rotor 420. This acceleration of the rotation of the centrifugal clutch rotor 420 in the first direction accelerates the rotation of the drive shaft 130 in the first direction. In this way, in the third mode, in which the rotation speed of the rotor 210 exceeds the rotation speed of the centrifugal clutch rotor 420 due to the driving force of the internal combustion engine 100 in the second mode, the driving force of the rotating electric machine 200 is added to the driving force of the internal combustion engine 100.

[0066] As a result, in the third mode, it is possible to achieve operation in which the rotating electric machine 200 assists the internal combustion engine 100. Therefore, while the first mode is an electric traveling mode using only the rotating electric machine 200, the third mode can be said to be an assist mode in which the rotating electric machine 200 assists the internal combustion engine 100. In addition, the second mode can be said to be an engine traveling mode in which the vehicle travels using the internal combustion engine 100.

[0067] The first to third modes have been explained above, but the relationship between switching between each mode and the operating state of the motorcycle 10 will be explained again below using Figure 12. In Figure 12, the vertical axis represents the rotation speed of each device, including the internal combustion engine 100 and the rotating electric machine 200, and the horizontal axis represents the time elapsed since the start of the motorcycle 10. Furthermore, the upward direction on the vertical axis represents the rotation speed in the first direction.

[0068] The first mode is when the rotating electric machine 200 starts to travel, and at the start of the first mode (P10), the speed of the two-wheeled vehicle is 0. The control device 250 starts the rotation of the rotating electric machine 200 with a voltage that generates sufficient starting torque in the rotating electric machine 200 (P10). At this time, the control device 250 controls the duty ratio and advance value so that the maximum torque is achieved within the allowable current. As described above, the rotation of the rotating electric machine 200 is reduced by the final gear 140 and transmitted to the drive shaft 130, so it is possible to start the two-wheeled vehicle 10 even if a rotating electric machine 200 with low torque is used.

[0069] Furthermore, when the rotating electric machine 200 starts, the rotating electric machine 200 rotates in the first direction (P10), and the rotation in the first direction is transmitted to the centrifugal clutch rotor 420 via the one-way clutch 600. Therefore, the centrifugal clutch rotor 420 also starts to rotate (P10). Furthermore, the drive shaft 130 also starts to rotate at the same time as the centrifugal clutch rotor 420 starts to rotate (P10).

[0070] During this start, as described above, the one-way clutch 600 and the second one-way clutch 610 transmit rotation so that the drive wheels 120 can rotate in the first direction. In other words, when the drive wheels 120 rotate in the second direction during start, the one-way clutch 600 and the second one-way clutch 610 transmit the rotation to the rotating electric machine 100 via the drive shaft 130, the one-way clutch 600, and the second one-way clutch 610. Therefore, the rotating electric machine 100 starts with a larger torque control to prevent rolling back when starting on a slope, etc.

[0071] After the motorcycle 10 begins to move, the control device 250 gradually increases the rotation speed of the rotating electric machine 200 by changing the frequency of the three-phase AC and the coil phase voltage (P100). The control device 250 performs 120-degree or 180-degree electrical angle control based on the outputs from the first through third Hall sensors 232, 233, and 234. In this first mode, the rotation speed of the rotating electric machine 200 matches the rotation speeds of the centrifugal clutch rotor 420 and the drive shaft 130, so the rotation speed of the centrifugal clutch rotor 420 also gradually increases (P103). Similarly, the rotation speed of the drive shaft 130 also gradually increases (P104). Accordingly, the rotation speed of the drive wheels 120 also increases, and the speed of the motorcycle 10 increases. The motorcycle 10 moves in the first mode up to a speed of approximately 5 to 10 kilometers per hour. The rotation speed of the rotating electric machine 200 increases to approximately 1,500 revolutions per minute. The state from start to this point, up to the time when the rotation speed of the rotating electrical machine 200 (that is, the drive shaft 130) is increased, is the first mode.

[0072] Next, the transition from the first mode to the second mode will be explained. When the rotation speed of the rotating electric machine 200 (drive shaft 130) increases to approximately 700 revolutions per minute, the switching from the first mode to the second mode begins. The internal combustion engine 100 is started at this point (P105). That is, the internal combustion engine 100 starts operating when the switching occurs after the first mode. At the time of this switching, the rotation speed of the rotating electric machine 200 is also increasing (P100), and the state in which the rotating electric machine 200 is driven and the internal combustion engine 100 coexists continues temporarily even after the internal combustion engine 100 starts.

[0073] Simultaneously with the start of the internal combustion engine 100, the driven pulley 410 also begins to rotate (P105), and as the rotation speed of the internal combustion engine 100 increases (P106), the rotation speed of the driven pulley 410 also increases (P107). As the rotation speed of the driven pulley 410 increases, the rotation speed of the rotating shaft 412 and the centrifugal clutch shoe 411 also increase. Then, receiving the centrifugal force caused by the rotation, the centrifugal clutch shoe 411 moves toward the centrifugal clutch rotor 420. However, because the centrifugal clutch rotor 420 is already rotating due to the rotating electric machine 200, the driving force in the first direction is transmitted from the driven pulley 410 to the centrifugal clutch rotor 420 side only when the rotation speed of the driven pulley 410 becomes higher than the rotation speed of the rotor 210 (P108). At this time, the rotation speed of the drive shaft 130 is approximately 1,100 revolutions per minute.

[0074] When the centrifugal clutch rotor 420 begins to rotate in the first direction due to the driving force transmitted through the driven pulley 410 of the internal combustion engine 100 (P108), the rotation speed of the centrifugal clutch rotor 420 increases (P109). Accordingly, the rotation speed of the drive shaft 130 in the first direction also increases (P110). More specifically, the rotation speeds of the centrifugal clutch rotor 420 and the drive shaft 130 continue to increase (P103, P104, P109), but after the point in time when the rotation speed of the driven pulley 410 exceeds the rotation speed of the drive shaft 130 (P108), the motorcycle 10 receives the driving force of the internal combustion engine 100 and accelerates. The driving force is switched to the internal combustion engine 100 when the rotation speed of the drive shaft 130 reaches approximately 1,100 to 1,500 revolutions per minute.

[0075] When the rotation speed of the driven pulley 410 becomes higher than the rotation speed of the rotor 210 (P108), the one-way clutch 600 blocks the rotation of the centrifugal clutch rotor 420 in the first direction, and power is not transmitted to the rotor 210. The rotor 210 spins freely due to the moment of inertia. In this state, the control device 250 switches the direction of the three-phase AC so as to switch the rotation direction of the rotor 210 from the first direction to the second direction (P112). Specifically, the control device 250 performs braking control by regenerative operation from the first direction rotation control (P112), thereby shortening the time until the vehicle stops (P111). During this switching, the one-way clutch 600 prevents power from being transmitted from the rotating electric machine 200 to the centrifugal clutch rotor 420. Therefore, even if the rotation speed of the rotating electric machine 200 becomes lower than the rotation speed of the centrifugal clutch rotor 420, there is no risk of the motorcycle 10 slowing down.

[0076] The speed of the motorcycle 10 when the centrifugal clutch mechanism 400 switches from non-transmission to transmission of power (P108) is set to approximately 5 to 10 kilometers per hour. However, switching from the first mode to the second mode is not performed solely based on the vehicle speed (the rotational speed of the rotating electric machine 200). The mode is switched based on a comprehensive determination of the vehicle speed, the required torque (accelerator opening), and the loads on the rotating electric machine 200 and the internal combustion engine 100. For example, when the accelerator opening exceeds a certain value, switching from the first mode to the second mode is performed even if the vehicle speed has not yet reached 5 to 10 kilometers per hour. For example, when starting on a slope, the driving force of the rotating electric machine 200 may be switched to the driving force of the internal combustion engine 100 early. Conversely, when starting on a downhill slope, the switching of the driving force from the rotating electric machine 200 to the internal combustion engine 100 may be delayed.

[0077] When switching from the first mode to the second mode, there is almost no change in the rotation speed of the drive wheels 120 and the drive shaft 130, which account for most of the moment of inertia. Furthermore, switching from the first mode to the second mode does not result in a change in the rotation direction of the centrifugal clutch rotor 420. Although the rotation speed of the centrifugal clutch rotor 420 increases (P109), this change does not directly affect the rotating electric machine 200, because it changes the one-way clutch 600 from a locked state to a free state. Therefore, the rotating electric machine 200 is controlled to stop without being affected by the rotation of the centrifugal clutch rotor 420 (P112).

[0078] As described above, when the power transmission switches from the first mode to the second mode, the power source for the centrifugal clutch rotor 420 switches from the rotating electric machine 200 to the internal combustion engine 100. In other words, since the rotation of the rotor 210 in the first direction is no longer necessary to rotate the centrifugal clutch rotor 420 in the first direction at a predetermined rotation speed, the rotating electric machine 200 stops operating. Although there is a certain amount of moment of inertia, the brake control of the rotating electric machine 200 allows for a smooth switch from the first mode to the second mode.

[0079] Therefore, as described in the second mode, magnetic friction loss due to the rotating electric machine 200 does not occur even during the transition from the first mode to the second mode. The transition from the first mode to the second mode begins when the internal combustion engine 100 starts (P105) and ends when the rotating electric machine 200 stops (P111).

[0080] Switching from the first mode to the second mode is performed by comparing the rotation speed of the internal combustion engine 100 and the rotation speed of the rotating electric machine 200. Switching from the first mode to the second mode can also be performed by the control device 250 detecting the load applied to the rotating electric machine 200. As described above, in the second mode, the driving force of the rotating electric machine 200 is not required, and therefore the torque that rotates the rotating electric machine 200 is zero. This torque fluctuation can be detected by the control device 250. For example, the torque may be referenced from the coil phase voltage and the output references from the first to third Hall sensors 232, 233, and 234. Depending on the detected torque fluctuation, braking (regeneration) control is performed, or the coil 224 is energized or de-energized.

[0081] In the second mode, the increase in speed of the centrifugal clutch rotor 420 in the first direction due to the increase in speed of the internal combustion engine 100 is blocked by the one-way clutch 600 and is not transmitted to the rotor 210 of the rotating electric machine 200. Furthermore, since the torque transmitted from the driven pulley 410 to the centrifugal clutch rotor 420 is always forward torque, the deceleration of the centrifugal clutch rotor 420 in the first direction due to the deceleration of the internal combustion engine 100 is also not transmitted to the rotor 210 of the rotating electric machine 200.

[0082] In the second mode, the motorcycle 10 travels at a constant speed of 20 kilometers per hour or more (P200). The internal combustion engine 100 is set to operate most efficiently when traveling at this constant speed. Therefore, the internal combustion engine 100 can be used in the most fuel-efficient state. In other words, since the second mode is a constant speed traveling state, sudden acceleration and deceleration are not performed as a rule.

[0083] Therefore, it is possible to hold the rotor 210 in a fixed position only by the rotation suppression torque from the permanent magnets 212 of the rotating electric machine 200. However, even in the second mode, the rotation speed of the internal combustion engine 100 does not have to be always constant. The rotation speed of the internal combustion engine 100 will fluctuate depending on the operating state.

[0084] When accelerating the motorcycle 10, the rotating electric machine 200 is used together with the internal combustion engine 100 in the third mode. Next, a transition from the second mode to the third mode when accelerating from constant speed driving (for example, 50 kilometers per hour) to approximately 60 kilometers per hour will be described. When acceleration is requested, the control device 250 rotates the rotating electric machine 200 in the first direction (P201). Then, the internal combustion engine 100 maintains the rotation speed in the constant speed driving state (P200).

[0085] Therefore, the centrifugal clutch rotor 420 rotates in the first direction due to the power obtained from the internal combustion engine 100. When accelerating using the rotating electric machine 200, the rotating electric machine 200 is rotated in the first direction. Since the first direction is the direction in which the one-way clutch 600 engages, the centrifugal clutch rotor 420 and the drive shaft 130 increase in speed (P202). The rotation of the centrifugal clutch rotor 420 in the first direction is transmitted to the drive shaft 130 via the second one-way clutch 610, so the rotation speed of the drive shaft 130 also increases (P203). Accordingly, the motorcycle 10 increases in speed from 50 kilometers per hour.

[0086] Although rotating electric machine 200 is required to rotate at a higher speed than the rotation speed in the first mode, the energy required for rotor 210 to catch up with the rotation speed of centrifugal clutch rotor 420 is not that great because the rotor is in an unloaded state. The main energy required to rotate drive shaft 130 at high speed is only the energy required for acceleration (P201). Furthermore, rotating electric machine 200 can control its rotation speed more quickly than internal combustion engine 100, so the user can experience a comfortable acceleration feeling.

[0087] However, acceleration of the motorcycle 10 is not performed solely by the rotating electric machine 200. When the rotation speed of the rotating electric machine 200 catches up with the rotation speed of the internal combustion engine (P212), the driving force that rotates the drive shaft 130 is transferred from the internal combustion engine 100 to the rotating electric machine 200. In other words, at this point (P212), the internal combustion engine 100 enters no-load operation. Therefore, the rotation speed of the internal combustion engine 100 also increases (P204). Conversely, if the rotation speed of the internal combustion engine 100 increases and exceeds the rotation speed of the rotating electric machine 200, the internal combustion engine 100 will now bear the load. Therefore, acceleration in the third mode can be performed more quickly by the rotating electric machine 200 assisting the internal combustion engine 100.

[0088] However, depending on the driver's acceleration needs obtained from the accelerator pedal position, it is also possible to selectively use acceleration performed by the internal combustion engine 100 alone and acceleration performed by combining the rotating electric machine 200 and the internal combustion engine 100. For the reasons described above, acceleration performed by combining the rotating electric machine 200 and the internal combustion engine 100 results in sharper acceleration.

[0089] Even when the rotational speed of the rotating electric machine 200 reaches a desired speed (e.g., 60 kilometers per hour) (P205), the rotating electric machine 200 maintains that rotational speed for a while to stabilize acceleration (P206). This state also corresponds to the third mode because acceleration is stabilized. Then, to return to the original constant-speed operation in the second mode after acceleration is completed, the speed increase by the rotating electric machine 200 is stopped (P207). In order to shorten the time until the rotation of the rotating electric machine 200 stops (P208), the control device 250 performs brake control (P209). As a result of the rotational speed increase and stop of the rotating electric machine 200 (P207), the rotation of the centrifugal clutch rotor 420 in the first direction becomes faster than that of the rotor 210, but this rotation of the centrifugal clutch rotor 420 is blocked by the one-way clutch 600 and is not transmitted to the rotor 210. This is similar to the control when switching from the first mode to the second mode.

[0090] As the rotating electric machine 200 accelerates and stops (P207), the internal combustion engine 100 takes over the rotation of the centrifugal clutch rotor 420 (P2050). That is, from this point (P2050), the rotation speed of the centrifugal clutch rotor 420 becomes constant (P210). There is a slight time lag from the point (P205) at which the rotation speed of the rotating electric machine 200 peaks out. There is also a slight time lag from the point (P2051) at which the internal combustion engine 100 begins to drive the driven pulley 410, but from that point on, the rotation speed of the internal combustion engine 100 (P211) and the rotation speed of the centrifugal clutch rotor 420 (P210) match. As the rotation speed of the centrifugal clutch rotor 420 is maintained, the rotation speed of the drive shaft 130 is also maintained (P213). The motorcycle 10 ends acceleration and returns to the second mode, which is constant speed driving.

[0091] To stop the two-wheeled vehicle 10, the brakes on the drive wheels 120 of the two-wheeled vehicle 10 are applied. When the brakes are applied, the drive shaft 130 rotates in a first direction relative to the centrifugal clutch rotor 420. This rotation of the drive shaft 130 in the first direction is not transmitted to the centrifugal clutch rotor 420 by the second one-way clutch 610.

[0092] Note that the above description is of the normally expected usage of the motorcycle 10, but each mode can also be used in other ways. For example, if the battery 351 does not have enough remaining power and starting in the first mode is difficult, the motorcycle 10 is started using the internal combustion engine 100. The driving force of the internal combustion engine 100 is transmitted from the driven pulley 410 to the drive wheel 120 via the centrifugal clutch rotor 420 and the second one-way clutch 610. In this case, the motorcycle starts using the internal combustion engine 100, and the second mode is maintained as is. However, after starting using the internal combustion engine 100, acceleration in the third mode may be performed.

[0093] In the above example, braking control is performed at the end of the transition from the first mode to the second mode and at the end of the transition from the third mode to the second mode. This is desirable control in order to stop the rotation of the rotating electric machine 200 early. However, this control is not essential. Once the transition from the first mode to the second mode or the transition from the third mode to the second mode is completed, it is also possible to simply stop the supply of current to the rotating electric machine 200.

[0094] As described above, according to the present disclosure, the motorcycle 10 can be driven with high energy efficiency. First, the motorcycle 10 is started in the first mode using only the rotating electric machine 200. At this time, the rotating electric machine 200 has a large starting torque, allowing the motorcycle 10 to start smoothly. After the motorcycle 10 reaches a predetermined steady state, the mode is switched to the second mode. When switching from the first mode to the second mode, the rotation from the centrifugal clutch rotor 420 is interrupted by the one-way clutch 600. Therefore, the rotation of the rotating electric machine 200 can be stopped by brake control.

[0095] In the second mode, the internal combustion engine 100 can be operated in the most efficient state. Furthermore, because the motorcycle 10 is in steady operation, the torque required by the drive wheels 130 is stable and torque fluctuations are reduced. Therefore, as described above, torque fluctuations transmitted from the centrifugal clutch rotor 420 to the rotating electric machine 200 during deceleration of the internal combustion engine 100 can be reduced. Therefore, the rotor 210 can be made non-rotating by the rotation suppression torque of the permanent magnet 212 when de-energized. This makes it possible to stop the rotating electric machine 200 when de-energized. As a result, it is also possible to eliminate magnetic friction loss in the rotating electric machine 200 that accompanies rotation when de-energized.

[0096] To further accelerate the motorcycle 10, the motorcycle is switched to the third mode. In this third mode, the driving force of the rotating electric machine 200 is added as an assist force while the internal combustion engine 100 is operating at optimal efficiency. In other words, the internal combustion engine 100 can be operated efficiently, improving fuel efficiency during acceleration. Furthermore, since rapid acceleration is possible as needed, the driving feel is not impaired.

[0097] Next, a modified example of the present disclosure will be described with reference to FIG. 13. Similar components to those in the above-described embodiment are designated by similar reference numerals. In the embodiment shown in FIG. 13, the second one-way clutch 610 is eliminated, and the centrifugal clutch rotor 420 is directly coupled to the drive shaft 130. This allows the centrifugal clutch rotor 420 and the drive shaft 130 to rotate integrally, making it possible to use the engine brake of the internal combustion engine 100 when controlling the brakes on the drive wheels 120 of the motorcycle 10. As will be described later, when the present disclosure is used as an aftermarket auxiliary drive device, the modifications to the drive shaft 130 can be minimized. However, the engine brake of the internal combustion engine 100 can be used only when the centrifugal clutch mechanism 400 is engaged and the centrifugal clutch rotor 420 and the driven pulley 410 are rotating together.

[0098] In the above example, the stator 220 is disposed on the inner periphery of the rotor 210, but as shown in Fig. 14, the rotor 210 may be disposed on the inner periphery of the stator 220. In the example of Fig. 14, the stator 220 is also fixed to the fixed cover 150 by the base portion 221. A permanent magnet 212 is disposed on the outer periphery of the cylindrical portion 211 of the rotor 210 disposed on the inner periphery. In this arrangement, the permanent magnet 212 faces the coil 224 of the stator 220, as in the above example.

[0099] Furthermore, in the above-described example, one-way clutch bar 632 is used as one-way clutch 600, but a cam mechanism may also be used as shown in Figures 15, 16, and 17. In the cam mechanism, a large number of one-way clutch cams 636 are arranged between inner circumferential ring 630 and outer circumferential ring 631. The surface of one-way clutch cam 636 that comes into contact with inner circumferential ring 630 is an arcuate surface 6360, and is rotatable on inner circumferential ring 630. A first flat surface 6361, a cam surface 6362, and a second flat surface 6363 are formed on the surface of one-way clutch cam 636 that faces outer circumferential ring 631.

[0100] FIG. 17 shows the engaged state of the one-way clutch 600. In the example of FIG. 17, when the inner circumferential ring 630 rotates counterclockwise, the outer circumferential ring 631 rotates clockwise, or both, the first flat surface 6361 meshes with the inner surface of the outer circumferential ring 631, and the arcuate surface 6360 meshes with the outer surface of the inner circumferential ring 630. The multiple one-way clutch cams 636 are instantly engaged with each other with uniform load due to the action of the springs 637. In other words, the rotation of the rotor 210 in the first direction is immediately transmitted to the centrifugal clutch rotor 420. This is suitable for use when transmitting the driving force of the rotating electric machine 200 to the centrifugal clutch rotor 420 in the first mode in which no centrifugal force is applied to the one-way clutch cams 636.

[0101] Conversely, as shown in Figure 15, when inner ring 630 rotates clockwise, if outer ring 631 rotates counterclockwise, no power is transmitted. In other words, rotation in the second direction of rotor 210 is not transmitted to centrifugal clutch rotor 420. Similarly, rotation in the first direction from centrifugal clutch rotor 420 is not transmitted to rotor 210. In this state, cam surface 6362 contacts the inner surface of outer ring 631, and arc surface 6360 contacts the outer surface of inner ring 630, but they do not mesh and spin freely. This is suitable for use in the second mode, in which the centrifugal force of one-way clutch cam 636 is not large, when rotation from centrifugal clutch rotor 420 is not transmitted to rotating electric machine 200.

[0102] Even when the one-way clutch cam 636 rotates at high speed, no power is transmitted. In other words, when the centrifugal clutch rotor 420 rotates in the first direction due to the driving force of the internal combustion engine 100, no power is transmitted. In this state, the centrifugal force acting on the one-way clutch cam 636 causes the second flat surface 6363 to contact the inner surface of the outer ring 631. A gap is then formed between the arcuate surface 6360 and the inner ring 630, preventing the transmission of rotation. Compared to the one-way clutch bar 632, the one-way clutch cam 636 more reliably interrupts transmission during idling. In the third mode, the outer ring 631 is already rotating at high speed, so the one-way clutch cam 636 is idling. Therefore, it is not suitable for the third mode in which the rotation of the rotating electric machine 200 is transmitted to the centrifugal clutch rotor 420.

[0103] In the above example, the hybrid drive system 1 using the internal combustion engine 100 and the rotating electric machine 200 has been described, but the present disclosure may also be applied to an auxiliary power unit that is retrofitted to a power unit that includes the internal combustion engine 100 and the centrifugal clutch mechanism 400. In other words, the auxiliary power unit is retrofitted to a two-wheeled vehicle 10 that includes the internal combustion engine 100, the drive pulley 105, the belt 106, the driven pulley 410, the final gear 140, and the drive shaft 130.

[0104] The retrofitting requires the extension of the drive shaft 130 and the modification of the centrifugal clutch rotor 420 and the fixed cover 150 of the centrifugal clutch mechanism 400. The rotary electric machine 200 and the control device 250 are also added as retrofitting parts. The one-way clutch 600 is also added. Wiring between the control device 250 and the rotary electric machine 200 is also added.

[0105] Although the above example is a preferred example of the present disclosure, the present disclosure is not limited to the above example. The material and size of each part can be changed as appropriate. The voltage of the battery 351 may be a high voltage of, for example, 48 volts, or a low voltage of, for example, 12 volts. Two types of batteries 351, one high voltage and one low voltage, may also be used.

[0106] Furthermore, in the above examples, the hybrid drive unit and auxiliary power unit are used in the two-wheeled vehicle 10, but the use of the hybrid drive unit and auxiliary power unit of the present disclosure is not limited to the two-wheeled vehicle 10. For example, they can also be used in other equipment such as motorboats, snowmobiles, and tractors. Therefore, the drive wheels 120 are an example of a drive unit, and the present disclosure can also be applied to drive units other than tires. [Explanation of symbols]

[0107] 10 Motorcycles 100 Internal combustion engine 150 control device 200 Rotating Electric Machine 250 control device 300 Second Rotating Electric Machine 400 centrifugal clutch mechanism 600 One-way clutch 610 Second one-way clutch

Claims

1. an internal combustion engine; a drive shaft that is rotatable by receiving the driving force of the internal combustion engine and transmits the driving force to a drive unit; a rotating electric machine including a rotor that has a plurality of permanent magnets arranged in a circumferential direction and is rotatable coaxially with the drive shaft, and a stator that is fixed to a fixed cover and has a plurality of coils that face the permanent magnets; a battery electrically connected to the rotating electric machine; a control device electrically connected to the battery and the rotating electric machine and controlling the rotation of the rotating electric machine; a centrifugal clutch mechanism in which the driving force of the internal combustion engine is not transmitted to the centrifugal clutch rotor when the rotation speed of the internal combustion engine is less than a predetermined number, and the driving force of the internal combustion engine is transmitted to the centrifugal clutch rotor when the rotation speed of the internal combustion engine is equal to or greater than the predetermined number; a one-way clutch interposed between the rotor of the rotating electric machine and the centrifugal clutch rotor, which transmits rotation of the rotor in a first direction to the centrifugal clutch rotor, does not transmit rotation of the rotor in a second direction opposite to the first direction to the centrifugal clutch rotor, and does not transmit rotation of the centrifugal clutch rotor in the first direction to the rotor, In a mode in which the rotation speed of the internal combustion engine is equal to or higher than a predetermined number and the driving force of the internal combustion engine is transmitted to the centrifugal clutch rotor, and electricity is not supplied to the rotating electric machine, the rotor does not rotate, and relative rotation does not occur between the rotor and the stator, and magnetic friction loss does not occur in the rotating electric machine. A hybrid drive device using an internal combustion engine and a rotating electric machine.

2. a second rotating electric machine driven by the internal combustion engine; the rotating electric machine is used as a drive motor for the drive shaft, The second rotating electric machine is used as a starter that starts the internal combustion engine and as a generator that charges the battery.

2. A hybrid drive system using an internal combustion engine and a rotating electric machine according to claim 1.

3. An auxiliary power unit used in a power unit including a drive shaft that is rotatable by receiving driving force from an internal combustion engine and transmits the driving force to a drive unit, and a centrifugal clutch mechanism that has a centrifugal clutch rotor and does not transmit the driving force of the internal combustion engine to the drive shaft when the rotation speed of the internal combustion engine is less than a predetermined number, and transmits the driving force of the internal combustion engine to the drive shaft when the rotation speed of the internal combustion engine is equal to or greater than the predetermined number, a rotating electric machine including a rotor that has a plurality of permanent magnets arranged in a circumferential direction and is rotatable coaxially with the drive shaft, and a stator that is fixed to a fixed cover and has a plurality of coils that face the permanent magnets; a control device for controlling the rotation of the rotating electric machine; a one-way clutch interposed between the rotor of the rotating electric machine and the centrifugal clutch rotor, which transmits rotation of the rotor in a first direction to the centrifugal clutch rotor, does not transmit rotation of the rotor in a second direction opposite to the first direction to the centrifugal clutch rotor, and does not transmit rotation of the centrifugal clutch rotor in the first direction to the rotor, In a mode in which the rotation speed of the internal combustion engine is equal to or higher than a predetermined number and the driving force of the internal combustion engine is transmitted to the centrifugal clutch rotor, and electricity is not supplied to the rotating electric machine, the rotor does not rotate, and relative rotation does not occur between the rotor and the stator, and magnetic friction loss does not occur in the rotating electric machine. An auxiliary power unit characterized by:

4. a second one-way clutch interposed between the centrifugal clutch rotor and the drive shaft, which transmits the rotation of the centrifugal clutch rotor in the first direction to the drive shaft and does not transmit the rotation of the drive shaft in the first direction to the centrifugal clutch rotor; 4. A hybrid drive system using the internal combustion engine and a rotating electric machine according to claim 1 or 2, or an auxiliary power unit according to claim 3.

5. The centrifugal clutch rotor and the drive shaft are coupled together and rotate together.

4. A hybrid drive system using the internal combustion engine and a rotating electric machine according to claim 1 or 2, or an auxiliary power unit according to claim 3.

6. The one-way clutch is a one-way cam clutch having a one-way clutch cam between an inner peripheral ring and an outer peripheral ring. A hybrid drive system using an internal combustion engine and a rotating electric machine according to claim 1 or 2 or claim 4 or 5 depending on claim 1 or 2, and an auxiliary power unit according to claim 3 or claim 4 or 5 depending on claim 3.

7. In a first mode in which the rotation of the drive shaft in the first direction is started, the rotor of the rotating electric machine is rotated in the first direction, and the rotation of the rotor is transmitted to the drive shaft via the one-way clutch and the centrifugal clutch rotor. A hybrid drive system using an internal combustion engine and a rotating electric machine as claimed in claim 1 or 2 or any one of claims 4 to 6 depending on claim 1 or 2, and an auxiliary power unit as claimed in claim 3 or any one of claims 4 to 6 depending on claim 3.

8. In a second mode in which the drive shaft steadily rotates in the first direction at a predetermined rotation speed or more, the rotation of the rotor of the rotating electric machine is stopped, and the rotation of the internal combustion engine is transmitted to the drive shaft via the centrifugal clutch rotor. A hybrid drive system using an internal combustion engine and a rotating electric machine as claimed in claim 1 or 2 or any one of claims 4 to 7 depending on claim 1 or 2, and an auxiliary power unit as claimed in claim 3 or any one of claims 4 to 7 depending on claim 3.

9. In a third mode in which the rotation speed of the drive shaft is further increased from a state in which the drive shaft rotates in the first direction at a predetermined rotation speed or more, the rotation of the internal combustion engine is transmitted to the drive shaft via the centrifugal clutch rotor, and the rotor of the rotating electric machine is rotated in the first direction, and the rotation of the rotor is also transmitted to the drive shaft via the one-way clutch and the centrifugal clutch rotor. A hybrid drive system using an internal combustion engine and a rotating electric machine according to claim 1 or 2 or any one of claims 4, 5, 7 and 8 depending on claim 1 or 2, and an auxiliary power unit according to claim 3 or any one of claims 4, 5, 7 and 8 depending on claim 3.

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