Balancer shaft control system

Abstract

To provide a balancer shaft control system which can suppress energy consumption.SOLUTION: A balancer control system includes a balancer shaft for suppressing vibration of an engine mounted on a vehicle, a first rotary electric machine for driving the balancer shaft, and a control device for controlling the first rotary electric machine, wherein the control device controls the first rotary electric machine according to the state of the vehicle and suppresses or stops the rotation of the balancer shaft.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a balancer shaft control system. [Background technology]

[0002] Conventionally, a balancer shaft for canceling engine vibrations has been known (see, for example, Patent Document 1). Such a balancer shaft rotates in synchronization with the rotation of the engine crankshaft. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-1423386 A Summary of the Invention [Problem to be solved by the invention]

[0004] The balancer shaft in Patent Document 1 rotates using the crankshaft as a power source. Therefore, the balancer shaft acts as a resistance and consumes energy. The balancer shaft can reduce energy consumption by suppressing or stopping the rotation.

[0005] An object of the present disclosure is to provide a balancer shaft control system that can reduce energy consumption. [Means for solving the problem]

[0006] The balancer control system of the present disclosure comprises a balancer shaft that suppresses vibrations of an engine mounted on a vehicle, a first rotating electric machine that drives the balancer shaft, and a control device that controls the first rotating electric machine, wherein the control device controls the first rotating electric machine depending on the state of the vehicle to suppress or stop rotation of the balancer shaft. Effect of the Invention

[0007] According to this configuration, since the balancer shaft is rotated electrically, it is possible to suppress or stop the rotation of the balancer shaft depending on the state of the vehicle, thereby making it possible to suppress energy consumption. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a system diagram of a balancer shaft control system according to one embodiment of the present disclosure. [Diagram 2] FIG. 1 is a side view of an engine according to one embodiment of the present disclosure. [Diagram 3] 4 is a flowchart showing a control procedure executed by a vehicle control device according to an embodiment of the present disclosure. [Figure 4] 5 is a graph showing the rotation speed of a balancer shaft during full-charge regeneration according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

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

[0010] 1 and 2, the control system 1 of the vehicle C includes an engine 2, a balancer shaft 3, a balancer shaft motor (an example of a first rotating electric machine) 4, a motor (FrM: an example of a third rotating electric machine) 5 for driving the vehicle C, a generator (GEN: an example of a second rotating electric machine) 6, a driving battery (BT) 7, a transaxle 8, an inverter 12 for controlling the motor 5 and the generator 6, an accelerator pedal 14 operated by a user of the vehicle C, a charger 16 connectable to an external power source, a power supply device (external power supply device) 18 capable of supplying power to an external device such as a home appliance, a vehicle control device (an example of a control device) 20, an engine control device 22 for controlling the engine 2, and a fuel tank (Fuel TANK) 24. In addition, the vehicle C may include, for example, a charge button (not shown) for a user to instruct charging. The vehicle C of this embodiment is a plug-in hybrid vehicle (PHEV) equipped with external charging that enables electric power from an external power source to be stored in the drive battery 7 by a charger 16, and external power supply that enables electric power from the drive battery 7 to be supplied to external devices by a power supply device 18.

[0011] As shown in FIG. 1, the engine 2 is connected to a generator 6 and drives the generator 6. Furthermore, in this embodiment, the engine 2 is capable of driving wheels C1 via a transaxle 8. The engine 2 in this embodiment is an in-line four-cylinder gasoline engine. The engine 2 receives fuel from a fuel tank 24 and burns and consumes the fuel. In this embodiment, the engine 2 is an in-line four-cylinder engine.

[0012] The balancer shaft 3 is a device for suppressing vibrations of the engine 2. As shown in FIG. 2, the rotation axis of the balancer shaft 3 is arranged parallel to the rotation axis of the crankshaft (one example of an output shaft) 2a. The balancer shaft 3 suppresses secondary vibrations caused by the inertial force and moment generated by the reciprocating motion of the pistons and connecting rods. When the pistons and connecting rods are displaced toward the top dead center, the center of gravity of the weight of the balancer shaft 3 is displaced in the opposite direction to the displacement of the pistons, etc., so as to cancel out the vibrations generated by the reciprocating motion of the pistons, etc. In this embodiment, the balancer shaft 3 has a first balancer shaft 3a and a second balancer shaft 3b arranged on the opposite side of the crankshaft 2a to the first balancer shaft 3a (see FIG. 1).

[0013] The balancer shaft motor 4 is a motor for driving the balancer shaft 3. As shown in FIG. 1, in this embodiment, the balancer shaft motor 4 is attached to each of the first balancer shaft 3a and the second balancer shaft 3b, and controls the two balancer shafts 3 separately. In this embodiment, the balancer shaft motor 4 is a DC brushless motor. The balancer shaft motor 4 is electrically connected to the engine control device 22 and is controlled by the vehicle control device 20 via the engine control device 22.

[0014] As shown in FIG. 1, the motor 5 is connected to the wheels C1 via a transaxle 8 and an axle 10 to drive the wheels C1. The motor 5 in this embodiment is a three-phase AC motor having a plurality of coils and a plurality of permanent magnets. The generator 6 is connected to the engine 2 and is capable of driving the engine 2. The generator 6 performs motoring to drive the engine 2 while the engine 2 is being powered by electric power from the drive battery 7. On the other hand, the generator 6 is driven by the engine 2 to generate electricity while the engine 2 is in operation. Therefore, the generator 6 is a motor-generator capable of powering and generating electricity.

[0015] The driving battery 7 outputs electric power to the motor 5 and the generator 6, and also receives electric power generated by the motor 5 and the generator 6. Furthermore, external electric power is input to the driving battery 7 via a charger 16. In this embodiment, the driving battery 7 is made up of multiple lithium ion batteries.

[0016] The transaxle 8 is configured to be able to connect and disconnect torque transmission between the crankshaft 2a of the engine 2 and the wheels C1. In this embodiment, the transaxle 8 has a plurality of gears and a clutch 8a. The engine 2 is connected to the generator 6 and the axle 10 via the transaxle 8. When the clutch 8a is in a disengaged state, the transaxle 8 disconnects power transmission between the engine 2 and the axle 10, and when the clutch 8a is in a engaged state, the power of the engine 2 is transmitted to the axle 10.

[0017] The inverter 12 converts the DC power supplied from the drive battery 7 into AC power, and adjusts the power supplied to the motor 5, thereby controlling the power running torque of the motor 5. When the motor 5 regenerates, the inverter 12 converts the AC power supplied from the motor 5 into DC power, and adjusts the power supplied to the drive battery 7, thereby controlling the regenerative torque of the motor 5.

[0018] The vehicle control device 20 is electrically connected to the motor 5 via the inverter 12, and is a device that controls the motor 5. The vehicle control device 20 is actually an ECU (Electronic Control Unit) that is configured by a microcomputer including a calculation device, a memory, an input / output buffer, etc. The vehicle control device 20 controls the vehicle C based on maps and programs stored in the memory.

[0019] The vehicle control device 20 of this embodiment is further electrically connected to an engine control device 22. The engine control device 22 is electrically connected to various devices equipped in the engine 2 and controls the engine 2. The control of the engine 2 may be performed by the vehicle control device 20 in addition to the engine control device 22. The vehicle control device 20 may also be electrically connected to various other devices of the vehicle C and perform various controls.

[0020] The vehicle C of this embodiment has driving modes such as an EV mode, a series mode, and a parallel mode. In the EV mode, the vehicle C drives the motor 5 with electric power from the driving battery 7. In the series mode, the vehicle C drives the generator 6 with the engine 2, and drives the motor 5 with electric power generated by the generator 6. In the parallel mode, the vehicle C connects the clutch 8a and drives the wheels C1 via the axle 10 with the power of the engine 2. The vehicle C may further have a charging mode. In the charging mode, the vehicle C drives the generator 6 with the engine 2, and stores the electric power generated by the generator 6 in the driving battery 7. In the vehicle C, the vehicle control device 20 switches between each driving mode according to the depression state of the accelerator pedal 14 and the operation state of the charge button, and controls the motor 5 and the generator 6 via the inverter 12, and causes the engine control device 22 to control the engine 2.

[0021] Furthermore, the vehicle C of this embodiment has an external power supply mode. In the external power supply mode, the vehicle control device 20 supplies power from the driving battery 7 to external devices using the power supply device 18. When the charging rate SOC (State Of Charge) of the driving battery 7 falls below a predetermined charging rate SOCt during the external power supply mode, the vehicle control device 20 executes an engine power generation external power supply mode (an example of power generation control) in which the engine 2 is started to drive the generator 6, and the power generated by the generator 6 is stored in the driving battery 7 and supplied to the external devices.

[0022] Next, a control procedure executed by the vehicle control device 20 will be described with reference to the flowchart of Fig. 3. In this embodiment, the control procedure starts when an ignition switch (not shown) is turned on.

[0023] In step S1, the vehicle control device 20 rotates the first balancer shaft 3a and the second balancer shaft 3b in synchronization with the rotation speed of the engine 2. In the following description, the state in which the balancer shaft 3 rotates in this manner is referred to as a normal state. After rotating the first balancer shaft 3a and the second balancer shaft 3b, the vehicle control device 20 proceeds to processing in step S2. Note that in this embodiment, an example will be described in which the vehicle control device 20 stops one or both of the first balancer shaft 3a and the second balancer shaft 3b depending on the running state while the first balancer shaft 3a and the second balancer shaft 3b are rotating.

[0024] In step S2, the vehicle control device 20 determines whether or not the mode is the series mode. If the vehicle control device 20 determines that the mode is the series mode (YES in step S2), the vehicle control device 20 advances the process to step S2.

[0025] In step S3, the vehicle control device 20 determines whether or not the vehicle is in the power mode. For example, the vehicle control device 20 may determine that the vehicle is in the power mode when the depression rate of the accelerator pedal 14 is equal to or greater than a predetermined rate (e.g., 80%). If the vehicle control device 20 determines that the vehicle is in the power mode (YES in step S3), the process proceeds to step S4. If the vehicle control device 20 determines that the vehicle is not in the power mode (NO in step S3), the vehicle control device 20 continues the normal state until the vehicle control device 20 enters the power mode.

[0026] In step S4, the vehicle control device 20 stops the rotation of the first balancer shaft 3a and the second balancer shaft 3b. In the power mode, sounds and vibrations other than those of the engine 2 become louder, and secondary vibrations of the engine 2 are less likely to be transmitted to the user. For this reason, the vehicle control device 20 prioritizes suppressing energy consumption by the balancer shaft 3. As a result, it is possible to suppress a decrease in the output of the engine 2 and a deterioration in fuel efficiency. After executing the process of step S4, the vehicle control device 20 proceeds to the process of step S2.

[0027] When the vehicle control device 20 determines in step S2 that the mode is not the series mode (NO in step S2), the vehicle control device 20 advances the process to step S5.

[0028] In step S5, the vehicle control device 20 determines whether or not the vehicle control device 20 is in the parallel mode. If the vehicle control device 20 determines that the vehicle control device 20 is in the parallel mode (YES in step S5), the process proceeds to step S6. If the vehicle control device 20 determines that the vehicle control device 20 is not in the parallel mode (NO in step S5), the process proceeds to step S10.

[0029] In step S6, the vehicle control device 20 determines whether or not the vehicle is accelerating slowly. The vehicle control device 20 may determine that the vehicle is accelerating slowly when, for example, the depression rate of the accelerator pedal 14 is equal to or greater than the rate of steady driving (e.g., 30% or more) and is less than the rate of power mode (e.g., less than 80%). If the vehicle control device 20 determines that the vehicle is accelerating slowly (YES in step S6), the process proceeds to step S7. If the vehicle control device 20 determines that the vehicle is not accelerating slowly (NO in step S6), the vehicle control device 20 proceeds to step S5 and maintains the normal state until the vehicle is accelerating slowly in the parallel mode.

[0030] In step S7, the vehicle control device 20 stops the rotation of the second balancer shaft 3b. In this embodiment, the vehicle control device 20 switches to the parallel mode when the speed of the vehicle C reaches a predetermined speed (for example, 60 km / h). Therefore, during slow acceleration in the parallel mode, the secondary vibration of the engine 2 is less likely to be transmitted to the user than during a steady running state. As a result, in the parallel mode, the vehicle control device 20 prioritizes suppression of energy consumption.

[0031] In step S8, the vehicle control device 20 determines whether or not the vehicle is in the power mode. The vehicle control device 20 may determine whether or not the vehicle is in the power mode in the same manner as in step S3. If the vehicle control device 20 determines that the vehicle is in the power mode (YES in step S8), the vehicle control device 20 proceeds to the process in step S9. If the vehicle control device 20 determines that the vehicle is not in the power mode (NO in step S8), the vehicle control device 20 proceeds to the process in step S7, and the rotation of the second balancer shaft 3b continues to be stopped.

[0032] In step S9, the vehicle control device 20 stops the rotation of the first balancer shaft 3a in addition to stopping the rotation of the second balancer shaft 3b. In the power mode during the parallel mode, sounds and vibrations other than those of the engine 2 are louder than in the series mode, and secondary vibrations of the engine 2 are less likely to be transmitted to the user. For this reason, the vehicle control device 20 prioritizes suppressing energy consumption by the balancer shaft 3. As a result, it is possible to suppress a decrease in the output of the engine 2 and a deterioration in fuel efficiency. After executing the process of step S9, the vehicle control device 20 proceeds to the process of step S2.

[0033] In step S10, the vehicle control device 20 determines whether or not the vehicle is decelerating. The vehicle control device 20 may determine that the vehicle is decelerating when a brake pedal (not shown) is depressed or when the accelerator pedal 14 is depressed. If the vehicle control device 20 determines that the vehicle is decelerating (YES in step S10), the process proceeds to step S11. If the vehicle control device 20 determines that the vehicle is not decelerating (NO in step S10), the process proceeds to step S15.

[0034] In step S11, the vehicle control device 20 determines whether or not fuel is being cut. A fuel cut refers to a state in which the engine 2 is stopped and the engine control device 22 has stopped the supply of fuel. If the vehicle control device 20 determines that fuel is being cut (YES in step S11), the vehicle control device 20 proceeds to the process in step S12. If the vehicle control device 20 determines that fuel is not being cut (NO in step S11), the vehicle control device 20 proceeds to the process in step S10, and continues the normal state until the vehicle enters a fuel cut state during deceleration.

[0035] In step S12, the vehicle control device 20 stops the rotation of the first balancer shaft 3a and the second balancer shaft 3b, and proceeds to the process of step S13.

[0036] In step S13, the vehicle control device 20 determines whether or not full charge regeneration is in progress. When the charging rate SOC of the driving battery 7 is equal to or higher than a threshold (for example, SOC is equal to or higher than 90%), the driving battery 7 cannot accept regenerated power. In this case, the vehicle control device 20 consumes the power generated by regeneration by motoring the engine 2 using the generator 6. In this embodiment, regenerative control in such a full charge state is called full charge regeneration. If the vehicle control device 20 determines that full charge regeneration is in progress (YES in step S13), the vehicle control device 20 proceeds to the process of step S14. If the vehicle control device 20 determines that full charge regeneration is not in progress (NO in step S13), the vehicle control device 20 proceeds to the process of step S12 and maintains the state in which the rotation of the balancer shaft 3 is stopped.

[0037] In step S14, the vehicle control device 20 rotates the first balancer shaft 3a and the second balancer shaft 3b in synchronization with the rotation speed of the engine 2. As shown in FIG. 4, the rotation speed of the first balancer shaft 3a and the second balancer shaft 3b may be set to be higher than that in the normal state. This makes it easier to consume the electric power generated by regeneration. After executing the process of step S14, the vehicle control device 20 proceeds to the process of step S2.

[0038] In step S15, the vehicle control device 20 determines whether or not the vehicle is in the charging mode. If the vehicle control device 20 determines that the vehicle is in the charging mode (YES in step S15), the vehicle control device 20 proceeds to step S16. If the vehicle control device 20 determines that the vehicle is not in the charging mode (NO in step S15), the vehicle control device 20 proceeds to step S18.

[0039] In step S16, the vehicle control device 20 determines whether the fuel level is low. The vehicle control device 20 may determine that the fuel level is low when the fuel level falls below a predetermined percentage level (e.g., 10%) of the capacity of the fuel tank 24. If the vehicle control device 20 determines that the fuel level is low (YES in step S16), the vehicle control device 20 proceeds to the process of step S17. If the vehicle control device 20 determines that the fuel level is not low (NO in step S16), the vehicle control device 20 proceeds to the process of step S15 and continues the normal state until the fuel level becomes low.

[0040] In step S17, the vehicle control device 20 stops the rotation of the first balancer shaft 3a and the second balancer shaft 3b, and proceeds to step S2. In this way, the vehicle control device 20 suppresses energy consumption by stopping the rotation of the balancer shaft 3. In this way, the vehicle control device 20 prioritizes charging over vibrations transmitted to the user.

[0041] In step S18, the vehicle control device 20 determines whether or not the vehicle control device 20 is in the external power supply mode. If the vehicle control device 20 determines that the vehicle control device 20 is in the external power supply mode (YES in step S18), the process proceeds to step S19. If the vehicle control device 20 determines that the vehicle control device 20 is not in the external power supply mode (NO in step S18), the vehicle control device 20 proceeds to step S1 and continues the normal state.

[0042] In step S19, the vehicle control device 20 determines whether or not the battery is in a low charged state. The vehicle control device may determine that the battery is in a low charged state, for example, when the charging rate SOC of the driving battery 7 is equal to or lower than a predetermined charging rate SOCt. If the vehicle control device 20 determines that the battery is in a low charged state (YES in step S19), the vehicle control device 20 proceeds to step S20. If the vehicle control device 20 determines that the battery is not in a low charged state (NO in step S19), the vehicle control device 20 proceeds to step S20 and continues the normal state until the battery is in a low charged state.

[0043] In step S20, the vehicle control device 20 stops the rotation of the second balancer shaft 3b. In the low charge state in the external power supply mode, it is preferable to continue the supply of power to the external device while suppressing fuel consumption. On the other hand, while a user is riding in the vehicle C, it is preferable to also suppress the transmission of vibration to the user. For this reason, the vehicle control device 20 suppresses secondary vibration of the engine 2 while suppressing energy consumption by stopping the rotation of the second balancer shaft 3b. After executing the process of step S20, the vehicle control device 20 proceeds to the process of step S21.

[0044] In step S21, the vehicle control device 20 determines whether or not an occupant (user) is present in the vehicle C. The vehicle control device 20 may detect a state in which a user is seated in the seat, for example, by a seat sensor not shown, and may determine that an occupant is not present in the vehicle C if the user is not detected as being seated. If the vehicle control device 20 determines that an occupant is not present in the vehicle C (step S21 YES), the process proceeds to step S22. If the vehicle control device 20 determines that an occupant is present in the vehicle C (step S21 NO), the process proceeds to step S20, and the state in which the rotation of the second balancer shaft 3b is stopped is continued.

[0045] In step S22, the vehicle control device 20 stops the rotation of the first balancer shaft 3a in addition to stopping the rotation of the second balancer shaft 3b. If the user is not inside the vehicle C, the vehicle control device 20 prioritizes suppressing energy consumption by the balancer shaft 3. As a result, it is possible to suppress deterioration of fuel efficiency during the external power supply mode. After executing the process of step S22, the vehicle control device 20 proceeds to the process of step S2.

[0046] As described above, the balancer shaft control system 1 of the present disclosure can suppress energy consumption by controlling the rotation of the balancer shaft 3 according to the state of the vehicle C, such as the parallel mode, the series mode, etc. Also, the balancer shaft control system 1 of the present disclosure can suppress energy consumption by controlling the rotation of the balancer shaft 3 according to the usage state of the engine 2, such as during fuel cut, motoring during full charge regeneration, etc.

[0047] <Other embodiments> Although the embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention. In particular, the multiple modifications described in this specification can be arbitrarily combined as necessary.

[0048] (a) In the above embodiment, the balancer shaft motor 4 is attached to each of the two balancer shafts 3, and the two balancer shafts 3 are controlled separately. However, the present disclosure is not limited to this. For example, one of the two balancer shafts 3 may be driven by the balancer shaft motor 4, and a transmission mechanism such as a gear may be provided to transmit the driving force of one balancer shaft 3 to the other balancer shaft 3. In this case, a clutch or the like may be provided in the transmission mechanism, so that one balancer shaft 3 may be rotated while the rotation of the other balancer shaft 3 is stopped.

[0049] (b) In the above embodiment, an example has been described in which the rotation of the first balancer shaft 3a and the rotation of the second balancer shaft 3b are stopped, but the present disclosure is not limited to this. The rotation of the balancer shaft 3 may be suppressed by lowering the rotation speed without completely stopping the rotation.

[0050] (c) In the above embodiment, the vehicle state is described as being in series mode, parallel mode, decelerating, charging mode, or external charging mode, but the present disclosure is not limited to this. For example, when the engine 2 is in a low temperature state, the balancer shaft 3 may be rotated to warm up the engine 2. [Explanation of symbols]

[0051] 1: Control system, 2: Engine 3: Balancer shaft 3a: First balancer shaft, 3b: Second balancer shaft 4: Balancer shaft motor, 7: Drive battery, 8: Transaxle 18: Power supply device, 20: Vehicle control device, 22: Engine control device 26: Power supply device C: Vehicle, C1: Wheel, SOC: Charge rate

Claims

1. A balancer shaft that suppresses vibrations of an engine mounted on a vehicle; a first rotating electric machine that drives the balancer shaft; A control device that controls the first rotating electric machine; Equipped with the control device controls the first rotating electric machine in accordance with a state of the vehicle to suppress or stop rotation of the balancer shaft. Balancer shaft control system.

2. the control device controls the first rotating electric machine in accordance with a usage state of the engine to suppress or stop rotation of the balancer shaft.

2. The balancer shaft control system of claim 1.

3. a second rotating electric machine driven by the engine; an external power supply device for supplying power to an external device of the vehicle; a driving battery capable of supplying power to the external power supply device; Further equipped with the control device executes power generation control in a case where the charging rate of the driving battery is low, to start the engine and drive the second rotating electric machine to generate power, and to supply the power generated by the second rotating electric machine to the external power supply device; suppressing rotation of the first rotating electric machine when the power generation control is in progress and when a user of the vehicle is not in the vehicle; 2. The balancer shaft control system of claim 1.

4. a third rotating electric machine that rotates wheels of the vehicle; a drive battery capable of receiving electric power regenerated by the third rotating electric machine; Further equipped with the control device, when the driving battery is fully charged, causes the first rotating electric machine to rotate and consumes the electric power regenerated by the third rotating electric machine.

2. The balancer shaft control system of claim 1.

5. a second rotating electric machine driven by the engine; a third rotating electric machine that rotates wheels of the vehicle; a driving battery capable of supplying electric power to the third rotating electric machine; a transaxle capable of connecting and disconnecting torque transmission between an output shaft of the engine and the wheels; Equipped with the control device is capable of switching a driving mode between a series mode in which the engine drives the second rotating electric machine and electric power generated by the second rotating electric machine is supplied to the third rotating electric machine, and a parallel mode in which output from the engine is transmitted to the wheels via the transaxle; controlling the rotation of the first rotating electric machine in accordance with the running mode; 2. The balancer shaft control system of claim 1.

6. The balancer shaft is A first balancer shaft and a second balancer shaft, The control device controls the rotation speed of the first balancer shaft and the rotation speed of the second balancer shaft in accordance with a running state of the vehicle. A balancer shaft control system according to any one of claims 1 to 5.

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