JP2014125137A - Structure of driving source of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a motor generator attached to an internal combustion engine from being damaged when the internal combustion engine is in high-speed rotation.SOLUTION: In a structure of a driving source of a vehicle having an internal combustion engine and a motor generator 5 as driving sources for driving an axle, an inner 51 and a crankshaft 13 are connected so that the inner 51 of the motor generator 5 receives torque transmission from the crankshaft 13 of the internal combustion engine, an outer 52 of the motor generator 5 is supported so as to be rotatable, and an engagement/disengagement clutch 62 is arranged between the outer 52 and a specified fixing member 14 to inhibit rotation of the outer 52 by engaging the clutch 62.

Description

  The present invention relates to a structure of a vehicle drive source capable of driving an axle by an internal combustion engine and a motor generator.

  2. Description of the Related Art There is a known vehicle in which the driving of an axle by an internal combustion engine is assisted by a motor generator, or the motor generator can drive the axle by replacing the internal combustion engine (see, for example, the following patent document).

  In order to perform cranking at the start of the internal combustion engine by the motor generator, it is necessary to make the specification of the motor generator generate a large torque at a low speed. On the other hand, a motor generator capable of generating a large torque even at low speed rotation is weak against high speed rotation. Therefore, the motor generator may be damaged when the internal combustion engine rotates at a high speed.

Japanese Patent Application Laid-Open No. 06-048222

  The main object of the present invention is to prevent a motor generator associated with an internal combustion engine from being damaged during high-speed rotation of the internal combustion engine.

  The structure of the vehicle drive source according to the present invention includes an internal combustion engine and a motor generator as a drive source for driving the axle, so that the inner of the motor generator can receive torque from the crankshaft of the internal combustion engine. The inner and crankshafts are connected to each other to rotatably support the motor generator outer, and a clutch that can be connected and disconnected is interposed between the outer and a predetermined fixing member, and this clutch is connected. The rotation of the outer can be restrained.

  With this configuration, the clutch can be disconnected when the crankshaft of the internal combustion engine rotates at high speed, and the outer of the motor generator can be rotated following the inner and crankshafts. As a result, since the relative rotational speed difference between the inner and the outer is reduced, the motor generator can be prevented from being damaged.

  In order to efficiently rotate and drive the crankshaft of the internal combustion engine by the motor generator, a one-way clutch is interposed between the outer and a predetermined fixing member, and the rotation direction of the outer is limited to one direction by the one-way clutch. It is preferable.

  The present invention can prevent a motor generator associated with an internal combustion engine from being damaged during high-speed rotation of the internal combustion engine.

The figure which shows schematic structure of the internal combustion engine in one Embodiment of this invention. The figure which shows typically the structural relationship of the internal combustion engine and motor generator in the embodiment.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an outline of an internal combustion engine for a vehicle in the present embodiment. The internal combustion engine in the present embodiment is a spark ignition type four-stroke engine and includes a plurality of cylinders 1 (one of which is shown in FIG. 1). In the vicinity of the intake port of each cylinder 1, an injector 11 for injecting fuel is provided. A spark plug 12 is attached to the ceiling of the combustion chamber of each cylinder 1. The spark plug 12 receives spark voltage generated by the ignition coil and causes spark discharge between the center electrode and the ground electrode.

  The intake passage 3 for supplying intake air takes in air from the outside and guides it to the intake port of each cylinder 1. On the intake passage 3, an air cleaner 31, an electronic throttle valve 32, a surge tank 33, and an intake manifold 34 are arranged in this order from the upstream.

  The exhaust passage 4 for discharging the exhaust guides the exhaust generated as a result of burning the fuel in the cylinder 1 from the exhaust port of each cylinder 1 to the outside. An exhaust manifold 42 and an exhaust purification three-way catalyst 41 are disposed on the exhaust passage 4.

  As shown in FIG. 2, the internal combustion engine in the present embodiment is accompanied by a motor generator 5 and an auxiliary machine 7. The motor generator 5 receives the function of an electric motor (starter and assist motor) that rotationally drives the crankshaft 13 of the internal combustion engine, and thus the vehicle axle (and drive wheels), and receives the driving force from the crankshaft 13 to generate electric power. It has both functions as a generator.

  When the crankshaft 13 and the axle are driven to rotate, the motor generator 5 is supplied with electric power from an in-vehicle battery (not shown). In turn, when the crankshaft 13 is rotationally driven to generate power, the generated power can be charged to the battery. In particular, the motor generator 5 performs regenerative braking when the vehicle decelerates and recovers the kinetic energy of the vehicle as electric energy.

  Inner inner 51 of motor generator 5 is arranged coaxially with crankshaft 13 of the internal combustion engine and is fixed to crankshaft 13. Therefore, the inner 51 always follows the crankshaft 13. In the present embodiment, the inner 51 is a rotor that contains a permanent magnet, and is rotatably supported by an outer 52 that is an armature (stator) that contains a coil.

  The outer 52 on the outer peripheral side of the motor generator 5 is supported so as to be rotatable with respect to the internal combustion engine or the vehicle body. The coil of the outer 52 and the battery circuit are electrically connected using, for example, a slip ring. The outer 52 is connected to a fixed member (for example, the chain cover 14 covering the timing chain of the internal combustion engine) via the one-way clutch 61. Therefore, the rotation direction of the outer 52 is limited to one direction.

  Further, a magnet clutch 62 is connected between the outer 52 and a fixed member (may be a chain cover 14 or a member other than the chain cover 14 in the internal combustion engine) as a clutch that can be switched between connection and disconnection. Intervened. If this magnet clutch 62 is connected, the outer 52 can be fixed without rotating.

  In the present embodiment, the water pump 7 which is a kind of auxiliary machine is connected to the outer 52 of the motor generator 5. Gear transmission mechanisms 521 and 71 are interposed between the outer 52 and the water pump 7. Specifically, a gear 521 fixed to the outer 52 and a gear 71 fixed to the input shaft of the water pump 7 are meshed so that torque can be transmitted from the outer 52 to the water pump 7. Upon receiving the torque input, the water pump 7 sucks and discharges the cooling water of the internal combustion engine, and circulates the cooling water.

  An ECU (Electronic Control Unit) 0 that controls the internal combustion engine and the motor generator 5 is a microcomputer system having a processor, a memory, an input interface, an output interface, and the like.

  The input interface includes a vehicle speed signal a output from the vehicle speed sensor that detects the actual vehicle speed of the vehicle, a crank angle signal b output from the engine rotation sensor that detects the rotation angle of the crankshaft 1310 and the engine speed, and the accelerator pedal. An accelerator opening signal c output from a sensor that detects the amount of depression or the opening of the throttle valve 32 as an accelerator opening (output required by the driver, so-called required load), and in the intake passage 3 (particularly, the surge tank 33) The intake air temperature / intake pressure signal d output from the temperature / pressure sensor for detecting the intake air temperature and the intake pressure, the coolant temperature signal e output from the water temperature sensor for detecting the engine coolant temperature, the intake camshaft or the exhaust camshaft The cam angle signal f output from the cam angle sensor at a plurality of cam angles indicates the charge state of the in-vehicle battery Battery signal g output from a sensor that detects battery voltage and / or battery current, armature voltage and / or armature current suggesting output (as motor) or power generation amount (as generator) by motor generator 5 An armature signal h or the like output from a sensor for detecting the signal is input.

  From the output interface, the ignition signal i for the igniter of the spark plug 12, the fuel injection signal j for the injector 11, the opening operation signal k for the throttle valve 32, and the motor generator 5 (control circuit thereof). A control signal l for controlling this, a connection signal m and the like are output to the magnet clutch 62. The control signal l instructs whether the motor generator 5 is operated as a motor or an alternator, and when the motor generator 5 is operated as a motor, the magnitude of a voltage (or current) applied to the motor generator 5 and the alternator Is a signal for controlling the magnitude of the voltage (or current) to be output from the motor generator 5 in the case of operating as. The connection signal m is a signal for energizing the magnet clutch 62 to connect it.

  The processor of the ECU 0 interprets and executes a program stored in the memory in advance, calculates operation parameters, and controls the operation of the internal combustion engine. The ECU 0 acquires various information a, b, c, d, e, f, g, and h necessary for operation control of the internal combustion engine via the input interface, knows the engine speed, and is filled in the cylinder 1. Estimate the intake volume. Based on the engine speed, the intake air amount, etc., the required fuel injection amount, fuel injection timing (including the number of times of fuel injection for one combustion), fuel injection pressure, ignition timing, output of the motor generator 5 or power generation Various operating parameters such as quantity are determined. The ECU 0 applies various control signals i, j, k, l and m corresponding to the operation parameters via the output interface.

  The vehicle in this embodiment may be a so-called hybrid vehicle.

  Hereinafter, modes of control of the internal combustion engine and the motor generator 5 by the ECU 0 of the present embodiment will be described.

  <Starting of Internal Combustion Engine> During cranking for rotationally driving the crankshaft 13 of the internal combustion engine, power is supplied to the outer 52 of the motor generator 5 to cause the motor generator 5 to function as an electric motor.

  At this time, as the reaction of the inner 51 and the crankshaft 13 trying to rotate in the forward direction, the outer 52 tries to rotate in the opposite direction to the inner 51 and the crankshaft 13. However, the reverse rotation is blocked by the one-way clutch 61. Therefore, the torque generated by the motor generator 5 is reliably transmitted to the crankshaft 13 of the internal combustion engine. The outer 52 does not rotate, and the water pump 7 connected to the outer 52 does not rotate. The outer clutch 52 may be fixed by connecting the magnet clutch 62, but power is consumed by energizing the magnet clutch 62.

  When the internal combustion engine is completely exploded and the rotational speed of the crankshaft 13 due to fuel combustion exceeds the rotational speed of the inner 51 of the motor generator 5 that consumes power and rotates, the outer 52 is connected to the crankshaft 13 and the inner 51. Will begin to rotate forward. At the same time, the motor generator 5 that was an electric motor is switched to a generator.

  <Driving of auxiliary machine> In order to rotationally drive the water pump 7 which is an auxiliary machine, it is necessary to rotate the outer 52 of the motor generator 5. When the internal combustion engine is operating by burning fuel, the engine torque output from the internal combustion engine can be transmitted from the crankshaft 13 to the outer 52 via the inner 51 to rotate the outer 52 of the motor generator 5. It is.

  That is, when the magnet clutch 62 is not connected and the crankshaft 13 and the inner 51 are rotating in the forward direction, the outer 52 is rotated in the forward direction so as to be dragged by these rotations. The forward rotation is not prevented by the one-way clutch 61. When the outer 52 rotates in the forward direction, the input shaft of the water pump 7 meshing with the outer 52 also rotates.

  The rotational speed and rotational torque of the outer 52 that is rotationally driven by the crankshaft 13 of the internal combustion engine vary according to the amount of power generated by the motor generator 5 that functions as a generator. If the power generation amount of the motor generator 5 is increased, the engine torque consumed in the motor generator 5 (converted into electric power) increases, and the rotational torque of the outer 52 decreases accordingly. As a result, the torque input to the water pump 7 decreases. Conversely, if the power generation amount of the motor generator 5 is decreased, the rotational torque of the outer 52 increases and the torque input to the water pump 7 also increases.

  That is, if the voltage (or current) output from the motor generator 5 via the inverter circuit or the like is adjusted by commanding from the ECU 0, the cooling water discharge flow rate (or discharge pressure) that is the output of the water pump 7 is adjusted. ) Can be operated. For example, when the amount of depression of the accelerator pedal is small and the required load on the internal combustion engine is relatively low, the amount of heat generated by the internal combustion engine is small and the demand for cooling performance is low. Therefore, the power generation amount of the motor generator 5 is increased and the output of the water pump 7 is decreased. In contrast, when the amount of depression of the accelerator pedal is large and the required load on the internal combustion engine is relatively high, the amount of heat generated by the internal combustion engine is large and the demand for cooling performance is high. The output of the pump 7 is increased.

  Incidentally, the water pump 7 can be rotationally driven by applying a reverse voltage to the outer 52, causing the motor generator 5 to function as an electric motor, and rotating the outer 52 in the forward direction. However, in this case, torque is generated to rotate the inner 51 and the crankshaft 13 in the reverse direction. Therefore, the reverse voltage is applied to the outer 52 when the rotation of the crankshaft 13 of the internal combustion engine is stopped (when the idling stop or the ignition switch is OFF) or when the temperature of the internal combustion engine (cooling water temperature) is remarkably increased. It is desirable to limit it to time.

  <Power generation> When the accelerator pedal depression amount becomes 0 or less than a predetermined value close to 0 while the vehicle is running, regenerative power generation may be performed using reverse torque returning from the axle to the crankshaft 13. it can.

  Alternatively, when the remaining charge of the in-vehicle battery is reduced or the power required by the vehicle electrical system is increased, the internal combustion engine generates power using the engine torque generated by burning the fuel. Therefore, it is necessary to supply the generated power to the battery and / or the electrical system.

  The magnitude of the electric power generated and output by the motor generator 5 depends on the relative rotational speed difference between the inner 51 and the outer 52 of the motor generator 5. As described in the section relating to driving of the auxiliary machine 7, it is possible to generate electric power without fixing the outer 52. However, in order to greatly increase the power generation amount, the outer 52 should be fixed so as not to rotate in order to increase the difference in rotational speed between the inner 51 and the outer 52. Therefore, when regenerative braking or when the battery charge is insufficient, the magnet clutch 62 is energized and connected. The electrical energy that can be recovered by regenerative braking is sufficiently larger than the energy consumed by energizing the magnet clutch 62.

  Further, when a deceleration request is made, the temperature of the internal combustion engine generally tends to decrease. Therefore, it is not necessary to rotate the water pump 7 via the outer 52.

  <Coast running operation> When the vehicle is coasting, the amount of depression of the accelerator pedal is 0 or less than a predetermined value close to 0, and the vehicle is coasting, the fuel cut that temporarily stops the fuel supply to the cylinder 1 is performed. Therefore, it is required to maintain the rotation of the axle and the crankshaft 13 of the internal combustion engine for as long as possible. Therefore, during coasting, the magnet generator 62 is connected and the outer 52 is fixed, while the power generation amount of the motor generator 5 serving as a generator is suppressed to the minimum (may be 0). Then, the engine torque consumed in the motor generator 5 is reduced.

  Since the temperature of the internal combustion engine decreases during coasting, it is not necessary to rotate the water pump 7 via the outer 52.

  <Low-load operation> When the amount of depression of the accelerator pedal is small and the required load on the internal combustion engine is relatively low, the engine speed is often low, and the thermal efficiency of the internal combustion engine decreases. Therefore, the rotation of the crankshaft 13 of the internal combustion engine is assisted by the motor generator 5 to suppress fuel consumption and improve fuel efficiency.

  At the time of motor assist for rotationally driving the crankshaft 13, the motor generator 5 is caused to function as an electric motor. In other words, the outer 52 of the motor generator 5 is energized to rotate the inner 51 in the forward direction. As described in the section relating to the start of the internal combustion engine, the one-way clutch 61 prevents the outer 52 from rotating in the reverse direction due to the reaction. There is no need to connect the magnet clutch 62 to fix the outer 52.

  <High load operation> When the amount of depression of the accelerator pedal is large and the required load on the internal combustion engine is relatively high, the magnet clutch 62 is disengaged and the outer 52 is free so that the motor generator 5 does not hinder the internal combustion engine. Ready for rotation. In addition, the power generation amount of the motor generator 5 serving as a generator is minimized. Then, the outer 52 rotates in the forward direction following the rotation of the inner 51 and the crankshaft 13, and the engine torque consumed in the motor generator 5 is reduced. At the same time, the water pump 7 can be continuously driven to rotate, and the circulation of the cooling water is maintained.

  <Acceleration transition period> In the process of increasing the engine speed and the vehicle speed, such as when the vehicle is started, the motor generator 5 is initially energized to function as an electric motor to assist the internal combustion engine. . Thereafter, the energization of the outer 52 is stopped, and the outer 52 is dragged by the inner 51 and the crankshaft 13 to rotate.

  The structure of the vehicle drive source according to the present embodiment includes an internal combustion engine and a motor generator 5 as a drive source for driving the axle and the auxiliary machine 7, and an inner 51 of the motor generator 5 is a crankshaft 13 of the internal combustion engine. The inner 51 and the crankshaft 13 are connected so that torque can be transmitted from the motor 51, and the outer 52 of the motor generator 5 is rotatably supported so that the auxiliary machine 7 can receive torque from the outer 52. The auxiliary machine 7 and the outer 52 are connected.

  According to this embodiment, when the internal combustion engine is operated by burning fuel, the rotational driving force of the crankshaft 13 can be transmitted to the auxiliary machine 7 via the outer 52 of the motor generator 5. . Even when the internal combustion engine is stopped, it is possible to operate the motor generator 5 as an electric motor and rotate the outer 52 to transmit the rotational torque to the auxiliary machine 7.

  The outer 52 has an outer diameter larger than that of the inner 51, and can be brought closer to the auxiliary machine 7 such as a water pump, and through a transmission mechanism other than the winding transmission mechanism (belt and pulley), in particular via gears 71 and 521. It is easy to connect the outer 52 and the auxiliary machine 7. In other words, since the outer 52 is a torque transmission member that connects the crankshaft 13 and the auxiliary machine 7, belts, pulleys, tensioners, etc. are not required, the number of parts is reduced, the structure is simplified, and the cost is reduced. Can do. Further, the degree of freedom in designing the arrangement of the auxiliary machine 7 with respect to the internal combustion engine is also increased.

  Further, since the rotation of the auxiliary machine 7 can be controlled by controlling the magnitude of the electric power generated by the motor generator 5, only the necessary part of the engine torque at that time is input to the auxiliary machine 7, and the rest It can be recovered by converting it into electric power. Further, since the rotational speed of the auxiliary machine 7 can be controlled regardless of the rotational speed of the internal combustion engine, the auxiliary machine 7 can be protected by preventing the auxiliary machine 7 from over-rotating in a situation where the engine speed is high. When it is necessary to increase the output of the auxiliary machine 7 (for example, the cooling water temperature is high and the discharge flow rate of the water pump 7 is increased), the amount of power generated by the motor generator 5 is reduced, and more torque is input to the auxiliary machine 7. You can also.

  The ECU 0 can estimate the magnitude of the electric power generated by the motor generator 5 by sensing the armature current and / or the armature voltage. When the rotation of the auxiliary machine 7 is controlled by operating the generated power of the motor generator 5 functioning as a generator, it is possible to grasp the magnitude of the load by the auxiliary machine 7 by obtaining the generated power. It is. Assuming that the engine torque is constant, it can be said that the smaller the generated power, the greater the mechanical energy consumed by the auxiliary machine 7, and the greater the load on the auxiliary machine 7.

  The ECU 0 of this embodiment corrects the output of the internal combustion engine according to the magnitude of the load of the auxiliary machine 7. That is, when the electric power generated by the motor generator 5 is small and the load by the auxiliary machine 7 is large, the amount of intake air charged into the cylinder 1 is increased (the opening degree of the throttle valve 32 is increased) as compared with the case where it is not. And increase the fuel injection amount. It is also advantageous that a measuring instrument that directly measures the load on the auxiliary machine 7 is not required.

  A clutch 62 that can be switched between connection and disconnection is interposed between the outer 52 and the predetermined fixing member 14, and the rotation of the outer 52 can be stopped by connecting the clutch 62. Therefore, it is desired to increase the amount of power generated by the motor generator 5. The outer 52 is sometimes fixed, and when it is desired to drive the auxiliary machine 7 by reducing the amount of power generated by the motor generator 5, the outer 52 can be unfixed. is there.

  If the clutch 62 is connected when the vehicle decelerates, the power recovered by regenerative braking can be increased, which contributes to further improvement in fuel efficiency.

  In addition, the structure of the vehicle drive source of the present embodiment includes an internal combustion engine and a motor generator 5 as drive sources for driving the axle, and the inner 51 of the motor generator 5 is torqued from the crankshaft 13 of the internal combustion engine. The inner 51 and the crankshaft 13 are connected so as to be able to receive the transmission, and the outer 52 of the motor generator 5 is rotatably supported, and the clutch can be switched between the outer 52 and the predetermined fixing member 14. The rotation of the outer 52 can be restrained by interposing 62 and connecting the clutch 62.

  According to the present embodiment, the clutch 62 is disengaged when the engine speed becomes high, and the outer 52 of the motor generator 5 is allowed to rotate following the inner 51 and the crankshaft 13, so that the motor An excessive increase in current flowing through the coil of the generator 5 can be suppressed. As a result, it is possible to prevent the motor generator 5 from being damaged.

  In addition, a one-way clutch 61 is interposed between the outer 52 and the predetermined fixing member 14, and the rotation direction of the outer 52 is limited to one direction by the one-way clutch 61. When the motor assists or the like, the rotation of the outer 52 of the motor generator 5 functioning as an electric motor in the reverse direction can be prevented. Since the one-way clutch 61 does not consume power unlike the magnet clutch 62, it is advantageous in terms of fuel consumption.

  The present invention is not limited to the embodiment described in detail above. For example, the one-way clutch 61 that prevents the outer 52 of the motor generator 5 from rotating in the reverse direction is not an essential element. If the outer 52 is fixed to be non-rotatable by the magnet clutch 62 at the time of starting the internal combustion engine or assisting the motor, the one-way clutch 61 can be eliminated.

  The connecting / disconnecting clutch 62 interposed between the outer 52 and the predetermined fixing member 14 is not limited to a magnet clutch, and may be a clutch driven by hydraulic pressure (hydraulic pressure).

  The type of the auxiliary machine 7 driven by receiving torque transmission from the outer 52 of the motor generator 5 is not limited to the water pump. The auxiliary machine 7 may be a compressor for refrigerant compression of an air conditioner.

  Torque may be transmitted from the outer 52 of the motor generator 5 to the plurality of auxiliary machines 7.

  Other specific configurations of each part can be variously modified without departing from the spirit of the present invention.

  The present invention can be applied to a vehicle in which an internal combustion engine and a motor generator 5 are mounted as drive sources.

0 ... Control unit (ECU)
13 ... Crankshaft of internal combustion engine 14 ... Fixing member (chain cover)
DESCRIPTION OF SYMBOLS 5 ... Motor generator 51 ... Inner 52 ... Outer 61 ... One-way clutch 62 ... Clutch (magnet clutch) which can be connected / disconnected
7 ... Auxiliary machines 521, 71 ... Gear transmission mechanism

Claims (2)

An internal combustion engine and a motor generator as a drive source for driving the axle,
Connecting the inner and crankshaft so that the motor generator inner can receive torque from the crankshaft of the internal combustion engine,
The motor generator outer is rotatably supported, and a clutch capable of switching connection / disconnection is interposed between the outer and a predetermined fixing member, and the rotation of the outer can be stopped by connecting the clutch. The structure of the vehicle drive source. The vehicle drive source structure according to claim 1, wherein a one-way clutch is interposed between the outer and a predetermined fixing member, and the rotation direction of the outer is limited to one direction by the one-way clutch.

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