Drive device and vehicle equipped with drive device

Abstract

To suppress increase of noise by suppressing rattling sound caused by variation components of power of an internal combustion engine.SOLUTION: A vehicle V includes an engine 1, and a gear train 46 for transmitting power of the engine 1 to a second motor generator 3. The gear train 46 has an engine gear 46a having a spline groove 46a2 engaged with a spline tooth 41a disposed on an engine shaft 41. A dimension d1 of the play D1 on an engagement part of the spline tooth 41a and the spline groove 46a2 is 97% or more to a vibration width W of a vibrational component in a rotating direction of the spline tooth 41a in rotating the engine 1 at a prescribed rotating speed Net.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to a drive unit and a vehicle equipped with the drive unit. [Background technology]

[0002] Patent Document 1 discloses a vehicle equipped with a transmission mechanism that transmits power generated by an electric motor to an output shaft to which the power generated by an internal combustion engine is transmitted via an engagement portion of a plurality of rotating members. In the vehicle described in Patent Document 1, gear rattle is suppressed by forming a play in the engagement portion of the transmission mechanism along the rotation direction of the rotating members that is greater than the amount of relative displacement between the rotating member on the internal combustion engine side and the rotating member on the electric motor side when the rotation fluctuation phase difference between the internal combustion engine and the electric motor is maximum, thereby suppressing noise. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2011 / 074042 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the vehicle described in Patent Document 1, the power generated by the internal combustion engine passes through multiple gear mechanisms before reaching the point where a large play is formed. Therefore, in these gear mechanisms, there is a risk that the fluctuation components of the power from the internal combustion engine will cause teeth rattle noise, resulting in increased noise.

[0005] The present invention has been made in consideration of such technical problems, and has an object to suppress gear rattle noise caused by fluctuation components of the power of an internal combustion engine, and to prevent noise from increasing. [Means for solving the problem]

[0006] According to one aspect of the present invention, a drive device includes an internal combustion engine and a power transmission mechanism for transmitting the power of the internal combustion engine to a rotating device. The power transmission mechanism includes a first rotor having a second meshing portion that meshes with a first meshing portion provided on an output shaft of the internal combustion engine, and the size of the play at the meshing portion between the first meshing portion and the second meshing portion is as follows: The output torque of the internal combustion engine is minimized. At a given rotation speed The output shaft The vibration amplitude of the vibration component in the rotation direction of the first meshing portion during rotation is 97% or more. Effect of the Invention

[0007] According to the present invention, even if the relative displacement between the first meshing portion and the second meshing portion fluctuates when the output shaft is rotating at a predetermined rotational speed, the first meshing portion and the second meshing portion can be prevented from colliding with each other to generate teeth rattle noise, thereby suppressing noise. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a drive system and a control system of a vehicle according to this embodiment. [Diagram 2] FIG. 2 is a schematic diagram of a power transmission path between the engine and the second motor generator in the vehicle of this embodiment. [Diagram 3] FIG. 3 is a diagram showing an example of the damper of the present embodiment. [Figure 4] FIG. 4 is an enlarged view of region B in FIG. 3, showing a state in which the inner hub and the outer hub are not in contact with each other. [Diagram 5] FIG. 5 is an enlarged view of region B in FIG. 3, showing the inner hub and the outer hub in contact with each other. [Figure 6] FIG. 6 is a diagram showing fluctuations in engine speed Ne when the engine is driven at a predetermined engine speed Net. [Figure 7] FIG. 7 is a diagram showing the change in the amount of displacement of the spline teeth when the engine is driven at a predetermined rotation speed Net. [Figure 8] FIG. 8 is a diagram for explaining the play in the spline connection. [Figure 9] FIG. 9 is a diagram for explaining play in gear engagement. [Figure 10] FIG. 10 is a diagram for explaining the relationship between the relative displacement between the spline teeth and the spline grooves and the play D1. [Figure 11] FIG. 11 is a diagram showing the relationship between the ratio of the size d1 of the play D1 to the vibration amplitude W and the sound pressure level. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] 1 is a schematic diagram of a drive system and a control system of a vehicle V according to an embodiment of the present invention. The vehicle V is a series hybrid vehicle that, for example, while the charging rate of the battery 5 is high, stops the engine 1 and runs on the electric motor for running (first motor generator 2), and when the charging rate of the battery 5 becomes low, drives a generator (second motor generator 3) by the engine 1 to generate electricity and runs on the electric motor for running (first motor generator 2).

[0011] As shown in FIG. 1, a vehicle V includes an engine 1 (ENG) as an internal combustion engine, a first motor generator 2 (MG1), a second motor generator 3 (MG2) as a rotating device, and a gear box 4 having a power transmission mechanism.

[0012] The engine 1 is, for example, a three-cylinder gasoline engine or diesel engine arranged in the front room of the vehicle V with the axial direction of the crankshaft 1a aligned in the vehicle width direction. The main body of the engine 1 is fixedly connected to a gear case 40 of a gear box 4. The crankshaft 1a of the engine 1 is connected to an engine shaft 41 of the gear box 4 via a flywheel 1b and a damper 1c serving as a damper. The engine 1 is started using the second motor generator 3 as a starter motor.

[0013] The first motor generator 2 is a three-phase AC permanent magnet synchronous motor powered by a battery 5 mounted as a drive source for traveling, and also has a regenerative function during deceleration and braking. The stator case of the first motor generator 2 is fixedly connected to a gear case 40 of the gear box 4. A first inverter 6 that converts DC to three-phase AC during power running and converts three-phase AC to DC during regeneration is connected to the stator coil of the first motor generator 2 via a first AC harness 6a. The first inverter 6 and the battery 5 are connected via a first DC harness 6b.

[0014] The second motor generator 3 is a three-phase AC permanent magnet synchronous motor powered by a battery 5 mounted as a generator, and has both a starter motor function for the engine 1 and a motoring operation function. A stator case of the second motor generator 3 is fixedly connected to a gear case 40 of the gear box 4. A rotor of the second motor generator 3 is connected to a second motor shaft 43 of the gear box 4. A second inverter 7 that converts DC to three-phase AC during power running and converts three-phase AC to DC during regeneration is connected to the stator coil of the second motor generator 3 via a second AC harness. The second inverter 7 and the battery 5 are connected via a second DC harness 7b. The second motor generator 3 corresponds to a rotating device of the present invention.

[0015] The gear box 4 includes a reduction gear train 44, a differential gear unit 45, and a gear train 46, which are housed in a gear case 40 to which the engine 1, the first motor generator 2, and the second motor generator 3 are fixedly connected. In this embodiment, the engine 1 and the gear train 46 correspond to the drive device of the present invention.

[0016] The reduction gear train 44 is a two-stage reduction gear train for reducing the rotation speed of the first motor generator 2 and increasing the motor torque to ensure the traveling drive torque, and includes a first motor shaft 42 and a first idler shaft 47. The reduction gear train 44 is a gear mechanism composed of a plurality of gears, and specifically includes a first motor gear 44a provided on the first motor shaft 42 and a large diameter idler gear 44b provided on the first idler shaft 47. In the reduction gear train 44, the first reduction gear stage is formed by meshing the first motor gear 44a and the large diameter idler gear 44b with each other. In the reduction gear train 44, a second reduction gear is formed by meshing a small diameter idler gear 44c provided on the first idler shaft 47 with an output gear 44d provided on the input side of the differential gear unit 45 with each other.

[0017] The differential gear unit 45 transmits the driving torque input via the output gear 44d of the reduction gear train 44 to left and right driving wheels 9, 9 (FIG. 1 shows only one wheel) via left and right drive shafts 8, 8 while allowing rotational differential.

[0018] The gear train 46 is a gear train that directly connects the engine 1 and the second motor generator 3 (generator) without using a clutch, and includes an engine shaft 41, a second idler shaft 48, and a second motor shaft 43. The gear train 46 is a gear mechanism made up of a plurality of gears, and specifically includes an engine gear 46a provided on the engine shaft 41, a second idler gear 46b provided on the second idler shaft 48, and a second motor gear 46c provided on the second motor shaft 43. In the gear train 46, the engine gear 46a, the second idler gear 46b, and the second motor gear 46c are meshed with each other to form the gear train 46.

[0019] As shown in Fig. 8, a plurality of spline teeth 41a as a first meshing portion are provided at equal intervals on the outer peripheral surface of the engine shaft 41 (six in Fig. 8), and the engine gear 46a is provided with a through hole 46a1 through which the engine shaft 41 is inserted, and a spline groove 46a2 as a second meshing portion into which the spline teeth 41a are fitted on the inner peripheral surface of the through hole 46a1. Thus, the engine shaft 41 and the engine gear 46a are connected by spline connection. Similarly, the second motor shaft 43 and the second motor gear 46c are spline-connected by fitting the spline teeth 43a as a third meshing portion provided on the outer peripheral surface of the second motor shaft 43 with the spline groove 46c2 provided in the through hole 46c1 through which the second motor shaft 43 of the second motor gear 46c is inserted as a fourth meshing portion.

[0020] The engine gear 46a, the second idler gear 46b, and the second motor gear 46c are formed of, for example, spur gears. The engine gear 46a, the second idler gear 46b, and the second motor gear 46c transmit power by meshing their respective teeth with each other. The relationship in the number of gear teeth is set as engine gear 46a>second motor gear 46c. As a result, the gear train 46 increases the rotation speed of the engine 1 during power generation operation and transmits the engine torque required for power generation by combustion operation (firing operation) to the second motor generator 3. On the other hand, during starter operation or motoring operation, the gear train 46 reduces the rotation speed of the second motor generator 3 and transmits the motor torque required for starter operation or motoring operation to the engine 1.

[0021] As shown in FIG. 1, the control system of the vehicle V includes a hybrid control module 10 (hereinafter, HCM), a power generation controller 11 (hereinafter, GC), a battery controller 12 (hereinafter, BC), a motor controller 13 (hereinafter, MC), and an engine controller 14 (hereinafter, EC).

[0022] The HCM 10 and other controllers (GC11, BC12, MC13, EC14, etc.) are connected to each other via a CAN communication line 15 to enable two-way information exchange. CAN is an abbreviation for Controller Area Network. The HCM 10 and other controllers (GC11, BC12, MC13, EC14) are collectively referred to as the controller 100. This controller 100 corresponds to the control device of the present invention.

[0023] The HCM 10 is an integrated control means that has the function of appropriately managing the energy consumption of the entire vehicle. That is, the HCM 10 reads information on the battery charging rate (hereinafter referred to as SOC (State Of Charge)) from the BC 12 via the CAN communication line 15. In addition, the HCM 10 reads information from an accelerator opening sensor 16, a vehicle speed sensor 17, an engine speed sensor 18, an engine coolant temperature sensor 19, an outside air temperature sensor 20, a door switch 21, a bonnet switch 22, an ignition switch 23, etc. Then, various controls are performed based on this information.

[0024] Next, a power transmission path A between the engine 1 and the second motor generator 3 (a portion surrounded by a dashed line in FIG. 1) will be described.

[0025] FIG. 2 is a schematic diagram of the power transmission path A.

[0026] A flywheel 1b, a damper 1c, and a gear box 4 are arranged in a power transmission path A between the engine 1 and the second motor generator 3. The damper 1c suppresses fluctuations in the torque transmitted from the engine 1 to the second motor generator 3.

[0027] An example of a damper 1c that can be used in this embodiment is shown in Fig. 3. Fig. 3 is a front view of the damper 1c. As shown in Fig. 3, the damper 1c includes an inner hub 30 connected to the engine shaft 41 of the gearbox 4, an outer hub 32 connected to the inner hub 30 via a low-elasticity damper 31, and a high-elasticity damper 33 that connects the outer hub 32 to the flywheel 1b. The low-elasticity damper 31 and the high-elasticity damper 33 are both metal springs, and the low-elasticity damper 31 is configured to have a lower spring constant than the high-elasticity damper 33.

[0028] The inner hub 30 has a hole 30b in the center into which the engine shaft 41 is inserted, and has a cutout on the outer periphery. The outer hub 32 has a cutout on the inner periphery at a position facing the cutout of the inner hub. The low-elasticity damper 31 is arranged expandably at a position defined by the cutout of the inner hub 30 and the cutout of the outer hub 32. In this embodiment, four low-elasticity dampers 31 are arranged, but this is not limited thereto, and for example two or three low-elasticity dampers 31 may be arranged.

[0029] The outer hub 32 also has a cutout on its outer periphery. The flywheel 1b has a cutout on its inner periphery at a position facing the cutout on the outer periphery of the outer hub 32. The high elasticity damper 33 is arranged expandably at a position defined by the cutout on the outer periphery of the outer hub 32 and the cutout on the flywheel 1b. In this embodiment, four high elasticity dampers 33 are arranged, but this is not limited thereto, and for example two or three high elasticity dampers may be arranged.

[0030] Figures 4 and 5 are enlarged views of the area B in Figure 3, with Figure 4 showing a state in which there is no twisting between the inner hub 30 and the outer hub 32, and Figure 5 showing a state in which the inner hub 30 and the outer hub 32 are in contact.

[0031] Although omitted in Fig. 3, a protrusion 30a is provided on the outer periphery of the inner hub 30, and a protrusion 32a is provided on the inner periphery of the outer hub 32. When there is no twisting between the inner hub 30 and the outer hub 32, as shown in Fig. 4, the protrusions 30a and the protrusions 32a are spaced apart from each other in the circumferential direction. When twisting occurs between the inner hub 30 and the outer hub 32, the protrusions 30a and the protrusions 32a rotate relative to each other, and the low-elasticity damper 31 contracts accordingly. Then, until the protrusions 30a and the protrusions 32a come into contact with each other as shown in Fig. 5, the low-elasticity damper 31 can absorb torque fluctuations.

[0032] The relationship between the outer hub 32, the flywheel 1b, and the high elasticity damper 33 is similar to the relationship between the inner hub 30, the outer hub 32, and the low elasticity damper 31. When the torque fluctuations become too great for the low elasticity damper 31 to absorb, the high elasticity damper 33 expands and contracts to absorb the torque fluctuations.

[0033] With this configuration, in the vehicle V, when the torque of the engine 1 is small, the torque fluctuations are absorbed by the low elasticity damper 31, and when the torque of the engine 1 is large, the torque fluctuations are absorbed by the high elasticity damper 33. In other words, by being equipped with the low elasticity damper 31 and the high elasticity damper 33, the vehicle V can absorb the torque fluctuations of the engine 1 in a wide engine operating range.

[0034] In the vehicle V, for example, when the SOC of the battery 5 reaches the upper charge limit and charging is not possible, the engine 1 may be driven for heating or the like. At this time, the controller 100 drives the engine 1 and the second motor generator 3 so as to minimize the output torque of the engine 1 in order to prevent deterioration of fuel efficiency. Specifically, the controller 100 drives the engine 1 at a predetermined rotation speed Net, and controls the second inverter 7 to drive the second motor generator 3, and rotates the gear train 46 by the power of the second motor generator 3. At this time, the controller 100 controls the rotation speed Nm of the second motor generator 3 so that the rotation speed Ngin of the engine shaft 41, which is the input shaft of the gear train 46, becomes equal to the rotation speed Net of the engine 1. In other words, the controller 100 drives the engine 1 and the second motor generator 3 so as to synchronize them. This makes it possible to suppress the second motor generator 3 from acting as a load on the rotation of the engine 1, thereby minimizing the output torque of the engine 1.

[0035] However, even if the engine 1 is instructed by the controller 100 to rotate at a predetermined rotation speed Net, the actual rotation speed Ne periodically varies around the target value, that is, the rotation speed Net, as shown in FIG.

[0036] A spline coupling portion in the gear train 46, specifically, a meshing portion between the spline teeth 41a and the spline groove 46a2, has a play D1, and a meshing portion between the spline teeth 43a and the spline groove 46c2 has a play D4 (see FIG. 8). A gear coupling portion in the gear train 46, specifically, a meshing portion between the engine gear 46a and the second idler gear 46b has a play D2, and a meshing portion between the second idler gear 46b and the second motor gear 46c has a play D3 (see FIG. 9). Fluctuations in the rotation speed Ne of the engine 1 can be absorbed by these plays D1 to D4.

[0037] However, when the fluctuation of the rotation speed Ne of the engine 1 is transmitted to the engine shaft 41, if the play D1 cannot absorb the fluctuation of the rotation speed Ngin of the engine shaft 41 due to the fluctuation of the rotation speed Ne of the engine 1, the spline teeth 43a periodically collide with the side of the spline groove 46c2. At this time, a collision sound (tooth rattle) between the spline teeth 43a and the side of the spline groove 46c2 may occur, which may cause noise. Furthermore, if the above fluctuation cannot be absorbed by the play D1, the rotation speed of the engine gear 46a will also fluctuate. As a result, the fluctuation is transmitted to the meshing portion between the engine gear 46a and the second idler gear 46b. If the fluctuation cannot be absorbed by the play D2, a collision sound (tooth rattle) between the teeth of the engine gear 46a and the teeth of the second idler gear 46b may occur, which may cause even louder noise.

[0038] Therefore, in this embodiment, the size d1 of the play D1 between the spline tooth 41a located closest to the engine 1 in the gear train 46 and the spline groove 46a2 is set to be equal to or larger than the amount of movement of the spline tooth 41a (engine shaft 41) when the engine 1 rotates at a predetermined rotation speed Net. This configuration will be specifically described below with reference to Figures 7, 10, etc. Note that the play in this embodiment refers to the play in the circumferential direction.

[0039] FIG. 7 is a diagram showing the displacement of the spline teeth 41a when the engine 1 is driven at a predetermined rotation speed Net. In FIG. 7, the displacement is set to 0 when the center of the spline groove 46a2 in the circumferential direction and the center of the spline teeth 41a in the circumferential direction coincide with each other. FIG. 10 is a diagram showing the relationship between the play D1 between the spline teeth 41a and the spline groove 46a2 and the fluctuation region of the spline teeth 41a, and is a conceptual diagram in which a cross section of the spline teeth 41a and the spline groove 46a2 along the circumferential direction is developed into a plane. FIG. 10 also shows a state in which the center of the spline groove 46a2 in the circumferential direction and the center of the spline teeth 41a in the circumferential direction coincide with each other, in other words, a state in which there is a play of half d1 on each side of the spline teeth 41a.

[0040] As described above, even if the engine 1 is instructed by the controller 100 to rotate at a predetermined rotation speed Net, the actual rotation speed Ne fluctuates slightly around the rotation speed Net. Accordingly, the spline teeth 41a of the engine shaft 41 connected to the crankshaft 1a of the engine 1 are periodically displaced in the circumferential direction within the spline grooves 46a2 (see FIG. 7). At this time, the spline teeth 41a are displaced within a range of a vibration width W (twice the amplitude D) according to the fluctuation of the engine 1 (see FIGS. 7 and 10). Note that the displacement here means a change in the relative positions of the spline teeth 41a and the spline grooves 46a2 in the circumferential direction (a displacement in the left-right direction in FIG. 10).

[0041] Therefore, in this embodiment, the size d1 of the play D1 between the spline teeth 41a and the spline grooves 46a2 is set to be equal to or larger than the vibration amplitude W (see FIG. 7) of the frequency component in the fluctuation of the spline teeth 41a. As a result, when the engine 1 is driven at a predetermined rotation speed Net so that the output torque of the engine 1 is minimized as described above, even if the spline teeth 41a fluctuate within the range of the vibration amplitude W (twice the amplitude D) (dotted line in FIG. 10), the spline teeth 41a and the spline grooves 46a2 do not come into contact with each other. This makes it possible to prevent the occurrence of rattle noise between the spline teeth 41a and the spline grooves 46a2 and suppress noise. Furthermore, since the fluctuation of the rotation speed Ne of the engine 1 can be absorbed by the play D1, it is also possible to prevent the occurrence of rattle noise in other gear coupling parts and spline coupling parts in the gear train 46.

[0042] In the above description, the magnitude d1 of the play D1 between the spline tooth 41a and the spline groove 46a2 is equal to or larger than the vibration width W. However, the magnitude d1 of the play D1 may be at least 97% or more of the vibration width W. As shown in FIG. 11, if the ratio of the magnitude d1 of the play D1 to the vibration width W is 97% or more, even if the spline tooth 41a and the spline groove 46a2 come into contact with each other, the sound pressure level of the tooth-crash sound between the spline tooth 41a and the spline groove 46a2 is reduced to a range that is permissible as noise. This is because, if the ratio of the magnitude d1 of the play D1 to the vibration width W is 97% or more, when the spline tooth 41a and the spline groove 46a2 come into contact with each other, the speed difference between the spline tooth 41a and the spline groove 46a2 immediately before the contact is reduced, and therefore the impact force generated at the time of contact is significantly reduced. Therefore, by setting the magnitude d1 of the play D1 to 97% or more of the vibration width W, noise can be sufficiently suppressed.

[0043] In addition, in this embodiment, the size d1 of the play D1 is made larger than the size d2 of the play D2 at the meshing portion between the engine gear 46a and the second idler gear 46b, the size d3 of the play D3 at the meshing portion between the second idler gear 46b and the second motor gear 46c, and the size d4 of the play D4 at the meshing portion between the spline teeth 43a and the spline grooves 46c2. That is, in this embodiment, the size of the play D1 located closest to the engine 1 in the gear train 46 is made the largest. If the play D2, D3, and D4 are made too large, there is a risk that the delay in power transmission and the deterioration of controllability may occur. Furthermore, there is a risk that the noise due to teeth rattling during normal operation may become large. Therefore, by making only the play D1 large, it is possible to absorb the fluctuation of the rotation speed Ne of the engine 1 while suppressing the delay in power transmission and the deterioration of controllability of other gear coupling parts and spline coupling parts.

[0044] In the above embodiment, the controller 100 rotates the engine 1 and the second motor generator 3 in synchronization with each other so that torque transmission does not occur between the engine 1 and the second motor generator 3. However, noise can be reduced in other situations. For example, when the second motor generator 3 is driven by the power of the engine 1, the spline teeth 41a rotate in a state of contacting one side surface of the spline groove 46a2. In this state, even if the rotation speed Ne of the engine 1 fluctuates, the spline teeth 41a can be prevented from colliding with the other side surface of the spline groove 46a2 by setting the size d1 of the play D1 to at least 97% or more of the vibration width W. This can suppress the generation of noise.

[0045] The configuration, operation, and effects of the embodiment of the present invention configured as above will be described below.

[0046] The drive device includes an engine 1 (internal combustion engine) and a gear train 46 (power transmission mechanism) for transmitting the power of the engine 1 (internal combustion engine) to a second motor generator 3 (rotation device). The gear train 46 (power transmission mechanism) has an engine gear 46a (first rotor) having a spline groove 46a2 (second meshing portion) that meshes with a spline tooth 41a (first meshing portion) provided on an engine shaft 41 (output shaft) of the engine 1 (internal combustion engine). A size d1 of a play D1 at a meshing portion between the spline tooth 41a (first meshing portion) and the spline groove 46a2 (second meshing portion) is 97% or more of a vibration amplitude W of a vibration component in a rotation direction of the spline tooth 41a (first meshing portion) when the engine shaft 41 (output shaft) rotates at a predetermined rotation speed Net.

[0047] When the engine shaft 41 (output shaft) rotates at a predetermined rotational speed Net, even if the relative displacement with the spline teeth 41a (first meshing portion) fluctuates, the spline teeth 41a (first meshing portion) and the spline groove 46a2 (second meshing portion) do not collide with each other to generate teeth rattle noise, thereby suppressing noise.

[0048] The magnitude d1 of the play D1 is equal to or greater than the vibration amplitude W.

[0049] By making the size d1 of the play D1 greater than or equal to the vibration amplitude W, collision between the spline teeth 41a (first meshing portion) and the spline groove 46a2 (second meshing portion) can be more reliably prevented, thereby more reliably preventing the generation of noise.

[0050] The gear train 46 (power transmission mechanism) is a gear mechanism composed of multiple gears (engine gear 46a, second idler gear 46b, second motor gear 46c), and the gear mechanism has an engine gear 46a (first rotating body) and a second motor gear 46c (second rotating body) having a spline groove 46c2 (fourth meshing portion) that meshes with spline teeth 43a (third meshing portion) provided on a second motor shaft 43 (rotating shaft) of the second motor generator 3 (rotating device). The magnitude d1 of the play D1 at the meshing portion between the spline tooth 41a (first meshing portion) and the spline groove 46a2 (second meshing portion) is larger than the magnitudes s2, d3 of the play D2, D3 at the meshing portions between the gears in the gear mechanism, and the magnitude d4 of the play D4 at the meshing portion between the spline tooth 43a (third meshing portion) and the spline groove 46c2 (fourth meshing portion).

[0051] By increasing only the play D1, it is possible to absorb fluctuations in the rotation speed Ne of the engine 1 (internal combustion engine), while suppressing delays in power transmission and deterioration of controllability in other gear connections and spline connections.

[0052] The drive device further includes a damper 1c (attenuator) that suppresses torque fluctuations transmitted from the engine 1 (internal combustion engine) to the gear train 46 (power transmission mechanism).

[0053] The damper 1c (attenuator) can absorb fluctuations in the rotation speed Ne of the engine 1. Therefore, by further providing the damper 1c (attenuator), it is possible to more reliably prevent the occurrence of gear rattle noise.

[0054] Engine 1 (internal combustion engine) is a three-cylinder engine.

[0055] In a three-cylinder engine, the fluctuation in the rotation speed Ne is large, so that a greater effect can be obtained by setting the magnitude d1 of the play D1 as described above.

[0056] The vehicle V includes an engine 1 (internal combustion engine), a gear train 46 (power transmission mechanism), a second motor generator 3 (rotation device), and a controller 100 (control device) that controls the operation of the engine 1 (internal combustion engine) and the second motor generator 3 (rotation device). The controller 100 (control device) rotates the engine 1 (internal combustion engine) and the second motor generator 3 (rotation device) in synchronization with each other so that no torque transmission occurs between the engine 1 (internal combustion engine) and the second motor generator 3 (rotation device).

[0057] When the controller 100 (control device) rotates the engine 1 (internal combustion engine) and the second motor generator 3 (rotating device) in synchronization with each other, no pressing force is generated between the spline teeth 41a (first meshing portion) and the spline grooves 46a2 (second meshing portion), so the teeth rattle noise becomes noticeable. Therefore, by setting the size d1 of the play D1 to 97% or more of the vibration width W, a significant effect can be obtained.

[0058] Although the embodiments of the present invention have been described above, the above-mentioned embodiments merely show some of the application examples of the present invention, and it is not intended that the technical scope of the present invention be limited to the specific configurations of the above-mentioned embodiments.

[0059] In the above embodiment, the vehicle V is provided with the damper 1c, but the vehicle V does not necessarily have to be provided with the damper 1c.

[0060] In the above embodiment, the engine 1 has three cylinders, but the engine may have any number of cylinders, such as four cylinders.

[0061] In the above embodiment, the rotating device is the second motor generator 3, but the present invention is not limited to this. The rotating device may be, for example, an auxiliary device such as a generator or a compressor.

[0062] In the above embodiment, the gear train 46 is used as an example of the power transmission mechanism, but other gear mechanisms may also be used.

[0063] In the above embodiment, the first to fourth meshing portions are splined, but the first to fourth meshing portions may be geared. For example, if the engine shaft 41 and the engine gear 46a are integrally configured, the meshing portions of the engine gear 46a and the second idler gear 46b may be the first meshing portion and the second meshing portion. [Explanation of symbols]

[0064] 1 Engine (internal combustion engine, drive unit) 1c Damper 2. First motor generator 3. Second motor generator (rotating device) 41 Engine shaft 41a Spline teeth (first meshing part) 42 First motor shaft 43 Second motor shaft 43a Spline teeth (third meshing part) 46 Gear train (power transmission mechanism, drive unit) 46a Engine gear (first rotating body) 46a2 Spline groove (second meshing part) 46b 2nd idler gear 46c Second motor gear (second rotating body) 46c2 Spline groove (fourth meshing part) 100 Controller (control device) D1, D2, D3, D4 Play

Claims

1. An internal combustion engine; a power transmission mechanism for transmitting the power of the internal combustion engine to a rotating device, The power transmission mechanism includes: a first rotor having a second meshing portion that meshes with a first meshing portion provided on an output shaft of the internal combustion engine; a magnitude of play at the meshing portion between the first meshing portion and the second meshing portion being 97% or more of a vibration amplitude of a vibration component in a rotational direction of the first meshing portion when the output shaft is rotating at a predetermined rotational speed at which an output torque of the internal combustion engine is minimized.

2. 2. The drive device according to claim 1, A drive device characterized in that the magnitude of the play is equal to or greater than the vibration amplitude.

3. A drive device according to claim 1 or 2, the power transmission mechanism is a gear mechanism constituted by a plurality of gears, the gear mechanism includes the first rotating body and a second rotating body having a fourth meshing portion that meshes with a third meshing portion provided on a rotating shaft of the rotating device, A drive device characterized in that the magnitude of play at the meshing portion between the first meshing portion and the second meshing portion is greater than the magnitude of play at the meshing portion between gears in the gear mechanism and the magnitude of play at the meshing portion between the third meshing portion and the fourth meshing portion.

4. A drive device according to any one of claims 1 to 3, The drive device further comprises a damper for suppressing torque fluctuations transmitted from the internal combustion engine to the power transmission mechanism.

5. A drive device according to any one of claims 1 to 4, The drive system, wherein the internal combustion engine is a three-cylinder engine.

6. A drive device according to any one of claims 1 to 5, The rotating device; a control device for controlling the operation of the internal combustion engine and the rotating device, the rotating device is an electric motor, The vehicle, wherein the control device rotates the internal combustion engine and the electric motor in synchronization with each other when rotating the output shaft at the predetermined rotational speed.

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