JP4779936B2 - Hybrid drive unit - Google Patents

Description

  The present invention relates to a hybrid drive device including a plurality of types of power units as a power source for traveling of a vehicle, and in particular, an internal combustion engine and a motor generator as output members via a power distribution mechanism having a differential action. The present invention relates to a hybrid drive device in which another motor generator is connected to an output member via a speed change mechanism capable of switching a gear ratio.

  A hybrid drive device for a vehicle is a drive device in which an internal combustion engine and an electric motor or a generator (hereinafter, collectively referred to as a motor generator) are combined and used as a power source. It is also used to control the rotational speed or operating point of an internal combustion engine instead of simply generating a driving force. In this case, since electric power is generated with the control of the rotational speed of the internal combustion engine, this is supplied to another motor generator and operated as a motor to generate a driving force.

  One example thereof is described in Patent Document 1. To briefly explain the basic configuration, the apparatus described in Patent Document 1 includes a planetary gear mechanism for power distribution, and an engine is connected to the carrier, and a first motor / generator is connected to the sun gear. Further, the output shaft is connected to the ring gear. Therefore, when the rotation speed of the output shaft is constant, the rotation speed of the engine can be appropriately controlled by changing the rotation speed of the first motor / generator. For example, the engine outputs predetermined power. By operating the first motor / generator as a generator and applying a reaction force to the sun gear in the state, the engine can be operated at the optimum fuel consumption point, and the output torque of the engine can be amplified and output to the output shaft. .

  The output shaft is connected to a transmission capable of changing the gear ratio between high and low, and a second motor / generator is connected to the input side of the transmission. And it is comprised so that electric power can be exchanged between the 2nd motor generator and the 1st motor generator. Therefore, in a state where the first motor / generator functions as a generator, the electric power generated by the first motor / generator is supplied to the second motor / generator to be distributed by the planetary gear mechanism for power distribution. A part of the engine power can be transmitted to the output shaft with power conversion. As a result, energy-efficient operation is possible, and necessary and sufficient driving force can be obtained.

  In Patent Document 2, an engine and a first motor / generator are connected to each other via a planetary gear mechanism for power distribution, and the second motor / generator is connected to an output member via a reduction gear having a constant reduction ratio. And a hybrid drive device including a clutch that couples the second motor / generator to the engine. Further, Patent Document 3 discloses that a clutch for connecting an engine and a first motor / generator to each other via a planetary gear mechanism for power distribution, a second motor / generator connected to an output member, a second motor / generator, and the like. A hybrid drive is described that includes a clutch that couples a generator to an engine.

Japanese Patent Laid-Open No. 2004-66898 JP 2004-336983 A Japanese Patent Laid-Open No. 11-332018

  In the apparatus described in Patent Document 1 described above, when the operating state of a vehicle on which the vehicle is mounted becomes a high vehicle speed and a low load, the rotational speed of the engine decreases and the rotational speed of the output shaft increases. -The generator is rotated in the negative direction (rotation direction opposite to the rotation direction of the engine) to function as a motor. In this case, the second motor / generator is rotated at an increased speed according to the transmission gear ratio provided between the second motor / generator and the output shaft to generate electric power. The electric power is supplied to the first motor / generator. Thus, in the case of high vehicle speed and low load, a state in which a part of the power output from the engine is again applied to the output shaft of the engine with power conversion, that is, power circulation occurs, resulting in a large power loss. This may reduce the fuel efficiency improvement effect. Further, in the device described in Patent Document 2 or 3, since the gear ratio between the second motor / generator and the output shaft cannot be changed, an operation mode suitable for the traveling state of the vehicle or the drive request state is set. It was difficult to set and there was room for improvement in order to improve energy efficiency or power transmission efficiency.

  The present invention has been made paying attention to the above technical problem, and an object of the present invention is to provide a hybrid drive device capable of diversifying operation modes and improving power transmission efficiency with a simple configuration. Is.

  In order to achieve the above-mentioned target, the invention of claim 1 is characterized in that the internal combustion engine, the first motor generator, and the output member are connected to a power distribution mechanism that performs a differential action by at least three rotating elements, and the output thereof. In the hybrid drive device in which the member is connected to the output side of the speed change mechanism capable of setting at least two high and low speed ratios, and the second motor generator is connected to the input side of the speed change mechanism, the internal combustion engine and the A clutch mechanism for selectively connecting the second motor generator is further provided.

  According to a second aspect of the present invention, in the first aspect of the invention, the transmission mechanism is configured to be able to set a neutral state in which torque is not transmitted, and the internal combustion engine and the The hybrid drive device further comprises first mode setting means for connecting an output to the two motor generators and setting an output split mode for setting the transmission mechanism in a neutral state.

  According to a third aspect of the present invention, in the second aspect of the present invention, the first mode setting means is configured such that the first motor generator has a negative rotational speed opposite to the rotational direction of the internal combustion engine. The hybrid drive apparatus includes means for setting the output split mode.

  According to a fourth aspect of the present invention, in the second or third aspect of the invention, the first mode setting means sets the speed change mechanism in a neutral state in a state where the rotational speed of the first motor generator is equal to or less than a predetermined rotational speed close to zero And a means for switching the clutch mechanism to the engaged state after the rotational speeds of the internal combustion engine and the second motor generator are synchronized in that state.

  According to a fifth aspect of the present invention, in the first aspect of the invention, in the state where the internal combustion engine is stopped, the transmission mechanism is brought into a neutral state and the clutch mechanism is brought into an engaged state. The hybrid drive device further comprises start control means for rotating the internal combustion engine by a machine.

  According to a sixth aspect of the present invention, in the first aspect of the invention, the speed change mechanism is set to a deceleration state capable of transmitting torque, and the clutch mechanism is engaged to connect the second motor generator to the internal combustion engine. The hybrid drive device further includes second mode setting means for setting a mechanical direct connection deceleration mode.

  In a seventh aspect of the invention, in the sixth aspect of the invention, the second mode setting means includes means for setting the mechanical direct-coupled deceleration mode when a load on at least one of the motor generators is relatively large. This is a hybrid drive device characterized in that.

  The invention according to claim 8 is the invention according to claim 6 or 7, wherein the second mode setting means switches to the mechanical direct-coupled deceleration mode after switching the speed ratio of the speed change mechanism from the low speed speed ratio to the high speed speed ratio. The hybrid drive device includes a switching means.

  According to a ninth aspect of the present invention, in any one of the sixth to eighth aspects, the motor generator that reduces the output torque of the second motor generator when the output torque of the internal combustion engine increases in the mechanical direct-coupled deceleration mode. The hybrid drive apparatus further includes a machine control means.

  According to a tenth aspect of the present invention, in the invention according to any one of the sixth to ninth aspects, the second mode setting means rotates the internal combustion engine and the second motor generator when the mechanical direct-coupled deceleration mode is set. The hybrid drive device includes means for engaging the clutch mechanism when the numbers are synchronized.

  The invention of claim 11 is the invention according to any one of claims 1 to 10, wherein the first motor generator, the power distribution mechanism, and the second motor generator are arranged on the same axis, and the power The hybrid drive device is characterized in that the distribution mechanism is disposed between the first motor generator and the second motor generator.

  According to a twelfth aspect of the present invention, in the invention according to any one of the first to eleventh aspects, the clutch mechanism is constituted by a meshing dog clutch mechanism, and the transmission mechanism is engaged to set the respective gear ratios. And a frictional engagement mechanism that can be switched to each of the released states.

  The invention of claim 13 is the invention according to any one of claims 1 to 12, wherein the power distribution mechanism is constituted by a planetary gear mechanism having a sun gear, a ring gear and a carrier as rotating elements, and the internal combustion engine is It is connected to one of the rotating elements in the planetary gear mechanism, the first motor generator is connected to another rotating element, the output member is further connected to another rotating element, and the clutch mechanism is connected to the internal combustion engine. The hybrid drive device is configured to selectively connect the connected rotating element and the second motor generator.

  According to the first aspect of the present invention, the speed ratio in the speed change mechanism between the second motor generator and the output member can be switched to at least high and low, and in addition, the internal combustion engine and the second motor generator are clutched. Since it can be directly connected by the mechanism, the settable driving states are more diversified than ever, and the power transmission efficiency can be improved by setting the driving mode according to the driving state.

  According to the invention of claim 2, the second motor generator can be disconnected from the output member by setting the speed change mechanism to the neutral state. Therefore, for example, in the case where a vehicle equipped with a hybrid drive device cruises at a high speed, the present invention rotates the second motor generator at a high speed or supplies the accompanying electric power to the first motor generator to function as a motor. Therefore, it is possible to avoid or suppress a situation where a large torque is generated, and to improve power transmission efficiency.

  According to the invention of claim 3, when the first motor generator rotates so-called negatively, the internal combustion engine and the second motor generator are connected, and the connection between the second motor generator and the output member is disconnected. Therefore, it is possible to avoid or suppress the situation in which the rotation speed of the second motor generator is increased or the electric power generated thereby is supplied to the first motor generator to function as a motor, thereby transmitting power. Efficiency can be improved.

  According to the fourth aspect of the present invention, when the clutch mechanism is engaged, the rotation speed is synchronized in advance, so that a change in the rotation speed due to the engagement of the clutch mechanism and a regenerative torque caused thereby are prevented or suppressed. , Shock and output torque steps can be avoided or suppressed.

  According to the invention of claim 5, the internal combustion engine can be started by driving the second motor generator in a state where the second motor generator is connected to the internal combustion engine by the clutch mechanism. In that case, since the speed change mechanism is in the neutral state and the second motor generator is cut off from the output member, the reaction force accompanying the start of the internal combustion engine does not appear in the output member, and thus the so-called reaction force Control for canceling is no longer necessary.

  According to the sixth aspect of the present invention, in the mechanical direct-coupled deceleration mode, a part of the power output from the internal combustion engine is transmitted to the output member via the power distribution mechanism, and the other power is transmitted via the clutch mechanism and the second motor generator. Is transmitted to the output member. Therefore, the amount of power transmitted from the internal combustion engine to the output member by so-called mechanical means increases, and as a result, power transmission efficiency can be improved.

  According to the seventh aspect of the present invention, when the load of the electric power generation increases, the mechanical direct-coupled deceleration mode is set and the transmission of power accompanied by power conversion is suppressed. Therefore, the load on the motor generator can be reduced to improve the durability of the electric system, the configuration can be simplified, and further, the power loss associated with the power conversion can be reduced to improve the power transmission efficiency.

  According to the eighth aspect of the present invention, when the mechanical direct coupling deceleration mode is set with the clutch mechanism engaged, the speed ratio of the speed change mechanism is set to the speed ratio on the high speed side to reduce the rotation speed of the second motor generator. Then, the second motor generator and the internal combustion engine are connected by engaging the clutch mechanism, so that the rotational speed of the internal combustion engine can be suppressed to a relatively low rotational speed after switching to the mechanical direct connection deceleration mode. it can.

  According to the invention of claim 9, since the output torque of the second motor generator can be made relatively small, the second motor generator can be made small and have a small capacity, and hence the hybrid drive device. It is possible to reduce the size of the overall structure.

  According to the tenth aspect of the present invention, when the mechanical direct coupling deceleration mode is set, the clutch mechanism is engaged. In this case, the clutch mechanism is established after the so-called rotation synchronization is established or close to the establishment. Is engaged, it is possible to prevent or suppress a shock accompanying switching of the operation mode.

  According to the invention of claim 11, it becomes easy to adopt a configuration in which a member having a large outer diameter is disposed on the internal combustion engine side and a member having a relatively small outer diameter is disposed on the opposite side. In addition, the in-vehicle property is improved, and in particular, the in-vehicle property for a so-called front engine rear wheel drive vehicle can be improved.

  According to the twelfth aspect of the present invention, when setting the output split mode, only the dog clutch mechanism is engaged as a so-called engagement mechanism, so the power split state is maintained and the output split mode is set. The power consumed to save the energy is almost unnecessary. For example, since the hydraulic pressure for maintaining the frictional engagement mechanism in the engaged state is not consumed, the oil pump loss can be reduced and the energy efficiency can be improved.

  According to the invention of claim 13, the same effects as those of the inventions of the above-described claims can be obtained.

  Next, the present invention will be described based on specific examples. FIG. 1 is a diagram showing a specific example of the present invention. In this specific example, a motor (engine: ENG) 1 and two motor generators (MG1, MG2) 2, 3 as generators or motors are shown. Are provided as a power unit. The prime mover 1 is an internal combustion engine, and is a power device that outputs power by burning fuel such as a gasoline engine, a diesel engine, or a natural gas engine. Preferably, the internal combustion engine can electrically control a load such as a throttle opening, and can set an optimum operating point with the best fuel consumption by controlling the rotational speed with respect to a predetermined load. In the following description, the prime mover 1 is referred to as the engine 1.

  The engine 1 is connected to a power distribution mechanism 4. The power distribution mechanism 4 is a mechanism for distributing the power output from the engine 1 to the first motor / generator 2 and the output side, and is constituted by a planetary gear mechanism that performs a differential action with three rotating elements. Yes. Specifically, the power distribution mechanism 4 can be configured using a single pinion planetary gear mechanism or a double pinion planetary gear mechanism. In the example shown in FIG. 1, the carrier Cf is the input element and the sun gear Sf is It is constituted by a single pinion type planetary gear mechanism having a force element and a ring gear Rf as an output element. That is, on the outer peripheral side of the sun gear Sf that is an external gear, a ring gear Rf that is an internal gear is arranged concentrically with the sun gear Sf, and the pinion gear that meshes with the sun gear Sf and the ring gear Rf is provided by the carrier Cf. It is held freely and revolving. An output member such as a crankshaft of the engine 1 is connected to the carrier Cf. Of course, a power transmission mechanism such as a starting clutch or a torque converter (a torque converter with a lock-up clutch) may be appropriately provided between the engine 1 and the carrier Cf.

  A first motor / generator (MG1) 2 corresponding to the first motor generator in the present invention is connected to the sun gear Sf of the power distribution mechanism 4. As an example, the first motor / generator 2 is configured by a synchronous motor including a permanent magnet in a rotor, and is configured to function as a generator and an electric motor. The rotor is connected to the sun gear Sf, and the stator is fixed to a casing (not shown) or the like.

  Further, the ring gear Rf is connected to the output shaft 5 corresponding to the output member of the present invention. The first motor / generator 2 and the power distribution mechanism 4 are arranged on the rotation center axis of the engine 1 in the order listed here, and the output shaft 5 has the engine 1, the first motor / generator 2 and the power. It is arranged on the same axis as the distribution mechanism 4.

  A second motor / generator (MG2) 3 corresponding to the second motor / generator of the present invention is arranged on the same axis on the opposite side of the power distribution mechanism 4 from the first motor / generator 2. The second motor / generator 3 mainly serves to perform so-called torque assist by receiving the electric power generated by the first motor / generator 2 and functioning as a motor. Since it is different from the motor / generator 2, for example, a high rotational speed type whose outer diameter is smaller than that of the first motor / generator 2 is used. The second motor / generator 3 is composed of a synchronous motor having a permanent magnet in the rotor, like the first motor / generator 2 described above, and functions as a generator and an electric motor. The rotor is connected to an input member of the speed change mechanism 6, and the stator is fixed to a casing (not shown) or the like.

  Each of the motor generators 2 and 3 functions as a generator and an electric motor. For this purpose, the motor generators 2 and 3 are connected to a power storage device such as a battery through a controller such as an inverter (not shown). Has been. The electric power generated by one motor / generator 2 or 3 is supplied to the other motor / generator 3 or 2 so that the other motor / generator 3 or 2 can function as a motor. .

  The speed change mechanism 6 is a mechanism for decelerating or increasing the power output from the second motor / generator 3 and transmitting the power to the output shaft 5 and is configured to be able to switch between at least two high and low speed ratios. Has been. More preferably, at least two gear ratios and a neutral state in which torque is not transmitted can be set. Therefore, the speed change mechanism 6 includes a mechanism composed of a low-speed gear pair and a high-speed gear pair, a mechanism composed of a set of planetary gear mechanisms and a clutch and a brake, and a compound planetary gear mechanism combining two sets of planetary gear mechanisms. A mechanism including an engagement device such as a brake can be used. An example is schematically shown in FIG. 2, and the example shown here is constituted by a so-called stepped pinion type planetary gear mechanism 7 and two brakes BHi and BLo.

  More specifically, a first sun gear S1 having a large diameter and a second sun gear S2 having a smaller diameter are disposed adjacent to each other on the same axis, and a pinion gear P1 having a small diameter meshes with the first sun gear S1. A relatively large pinion gear P2 meshes with the second sun gear S2. These pinion gears P1 and P2 are held by a carrier C so as to rotate and revolve. Further, a ring gear R disposed concentrically with the sun gears S1 and S2 meshes with one pinion gear (for example, a large-diameter pinion gear P2). The rotor of the second motor / generator 3 is connected to the ring gear R, and therefore the ring gear R is an input element. Further, the carrier C is connected to the output shaft 5, so that the carrier C is an output element. Further, the large-diameter first sun gear S1 is connected to the high brake BHi, and the small-diameter second sun gear S2 is connected to the low brake BLo. These brakes BHi and BLo correspond to the frictional engagement mechanism of the present invention. For example, the brakes BHi and BLo are engaged by transmitting hydraulic pressure to transmit torque, and are released by releasing the hydraulic pressure, so that the transmission torque capacity is increased. It is configured to decrease and gradually stop transmitting torque.

  Therefore, when power is input from the second motor / generator 3 to the ring gear R while the first sun gear S1 is fixed by the high brake BHi, the gear ratio, which is the ratio between the number of teeth of the first sun gear S1 and the number of teeth of the ring gear R. In response to this, a deceleration action is generated, and the torque input to the ring gear R is amplified and transmitted to the output shaft 5. When power is input from the second motor / generator 3 to the ring gear R with the second sun gear S2 fixed by the low brake BLo, a gear ratio that is a ratio between the number of teeth of the second sun gear S2 and the number of teeth of the ring gear R. In response to this, a deceleration action is generated, and the torque input to the ring gear R is amplified and transmitted to the output shaft 5. In this case, the reduction ratio when the first sun gear S1 is fixed is smaller than the reduction ratio when the second sun gear S2 is fixed. That is, the high speed gear ratio is set by engaging the high brake BHi, and the low speed gear ratio is set by engaging the low brake BLo. Further, when the brakes BHi and BLo are released together, the speed change mechanism 6 enters a neutral state where torque is not transmitted, and the second motor / generator and the output shaft 5 are disconnected. Therefore, the transmission mechanism 6 is set in three modes: a high speed transmission ratio, a low speed transmission ratio, and a neutral state.

  The hybrid drive apparatus shown in FIG. 1 further includes a clutch mechanism 8 that selectively connects the engine 1 and the second motor / generator 3. The clutch mechanism 8 may be any mechanism that connects the engine 1 and the input element of the second motor / generator 3 or the speed change mechanism 6 so as to be able to transmit torque, and is a friction type engagement mechanism or a mesh type engagement mechanism. A combination mechanism or the like can be employed. FIG. 1 shows an example in which a dog clutch which is a meshing engagement mechanism is employed, and a hub 9 integrally connected to the rotor of the second motor / generator 3 is connected to the second motor / generator 3. These are arranged on the outer peripheral side with respect to the power distribution mechanism 4. A sleeve 10 is splined to the hub 9 so as to be movable back and forth in the axial direction. Further, another hub 11 to which the sleeve 10 can be spline-fitted is disposed adjacent to the hub 9. The other hub 11 is connected to the carrier Cf in the power distribution mechanism 4 so as to rotate together.

  Therefore, when the sleeve 10 is moved to the right position in FIG. 1, the clutch mechanism 8 is in a released state in which the engine 1 and the second motor / generator 3 are disconnected, and the sleeve 10 is moved to the left position in FIG. As a result, the sleeve 10 is spline-fitted to the other hub 11 so that the engine 1 and the second motor / generator 3 are connected. Such movement of the sleeve 10 may be configured to be performed manually or may be configured to be performed by an appropriate actuator that can be electrically controlled.

  As shown in FIG. 1, the configuration in which the first motor / generator 2, the power distribution mechanism 4, the second motor / generator 3, and the transmission mechanism 6 are arranged in this order from the engine 1 side has a large outer diameter on the engine 1 side. The outer diameter on the opposite side of the is relatively small. Therefore, if it is configured as shown in FIG. 1, the vehicle mountability with respect to the front engine rear wheel drive vehicle in which the engine 1 is mounted in the front-rear direction of the vehicle is improved.

  Switching of the operation mode by engagement / release of the clutch mechanism 8 described above, switching of the shift or operation mode by engagement / release of the brakes BHi and BLo in the transmission mechanism 6, and regeneration / regeneration by the motor generators 2, 3 The power running control is configured to be performed electrically, and an electronic control unit (ECU) 12 is provided for this purpose. The electronic control unit 12 is mainly composed of a microcomputer, performs computation using data detected by a sensor (not shown) or data stored in advance, and outputs the result as a control command signal. It is configured.

  Next, the operation of the hybrid drive device described above will be described. First, the case of starting the engine 1 will be described. If the engine 1 has a starter motor as in the case of a normal vehicle engine, the engine 1 is motored (cranked) by the starter generator and the engine 1 is started. However, instead of this, the engine 1 can be motored and started by the second motor / generator 3 described above. When the engine 1 is motored by the second motor / generator 3, the brakes BHi and BLo in the transmission mechanism 6 are released and the clutch mechanism 8 is engaged. Specifically, the sleeve 10 is moved to the left in FIG. 1 and the sleeves 10 are engaged with the hubs 9 and 11 so that the engine 1 and the second motor / generator 3 can transmit torque. Link. Engagement / release control of the clutch mechanism 8 and the brakes BHi and BLo can be performed by a control command signal from the electronic control unit 12, and therefore the electronic control unit 12 corresponds to the start control means of the present invention. is doing.

  In this state, when electric power is supplied from the power storage device to the second motor / generator 3 and driven, the engine 1 is rotated by the second motor / generator 3 to supply fuel to the engine 1. The engine 1 is started by performing ignition control. In this case, since the brakes BHi and BLo in the speed change mechanism 6 are released and the connection between the second motor / generator 3 and the output shaft 5 is released, the output torque of the second motor / generator 3 is output to the output shaft. Therefore, the control for canceling the so-called reaction force for preventing the torque of the output shaft 5 from changing is unnecessary. In other words, torque fluctuation of the output shaft 5 can be prevented without performing any particular control, and a sense of incongruity such as a shock accompanying the start of the engine 1 can be avoided or suppressed.

  When the engine 1 is started and started, the clutch mechanism 8 is released to disconnect the engine 1 and the second motor / generator 3, and the transmission mechanism 6 engages the low brake BLo to change the speed. Set the ratio to the low gear ratio. Therefore, the power output from the engine 1 is transmitted to the carrier Cf in the power distribution mechanism 4 and distributed to the sun gear Sf and the ring gear Rf. Since the load is applied to the ring gear Rf from the output shaft 5 side, the sun gear Sf and the first motor / generator 2 connected to the sun gear Sf rotate in the forward direction (rotation in the same direction as the engine 1 or the carrier Cf). When the motor / generator 2 is caused to function as a generator and a reaction torque is applied to the sun gear Sf, a torque in the forward rotation direction acts on the ring gear Rf and the output shaft 5 connected thereto.

  On the other hand, since the electric power generated by the first motor / generator 2 is supplied to the second motor / generator 3 and functions as a motor, its output torque is amplified in accordance with the gear ratio of the transmission mechanism 6 and output shaft. 5 is transmitted. Accordingly, a part of the power output from the engine 1 is mechanically transmitted to the output shaft 5 via the power distribution mechanism 4, and the other power is transmitted to the output shaft 5 with power conversion. Then, the torque distribution effect of the power distribution mechanism 4 and the speed change mechanism 6 occurs, so that the torque of the output shaft 5, that is, the driving torque of the vehicle can be increased. In this case, the rotation speed of the engine 1 can be controlled by the first motor / generator 2 without changing the rotation speed of the output shaft 5, and the engine 1 can be operated with optimum fuel consumption. .

  When the engine load increases due to acceleration or climbing, and the rotation speed increases, the rotation speeds of the first motor / generator 2 and the second motor / generator 3 increase. That is, the power generation amount of the first motor / generator 2 increases, and the electric power is supplied to the second motor / generator 3, which outputs a large torque. This state is shown by a broken line in FIG. 3 as a collinear diagram for the power distribution mechanism 4 and the transmission mechanism 6. In this state, the transmission amount of power accompanying power conversion increases, and the load on the electric system increases. Therefore, when the load of the motor / generators 2 and 3 increases beyond a predetermined judgment reference value, the mode is switched to the machine direct-coupled deceleration mode to avoid a decrease in power transmission efficiency. Specifically, the clutch mechanism 8 is switched to the engaged state to mechanically connect the engine 1 and the second motor / generator 3. The determination reference value can be determined through experiments or simulations.

  The operation state in this mechanical direct connection (parallel) deceleration mode is shown in a collinear diagram in FIG. 4, and as described above, this is an operation mode set at the time of low speed and high load where the electrical load increases. In this mechanical direct-coupled deceleration mode, the power output from the engine 1 is directly input to the transmission mechanism 6 via the carrier Cf, the clutch mechanism 8 and the second motor / generator 3 in the power distribution mechanism 4, and further the deceleration by the transmission mechanism 6. The torque is amplified by the action and transmitted to the output shaft 5. In this case, as in the past, the first motor / generator 2 can generate electric power, and the second motor / generator 3 can be powered by the electric power. Therefore, in this mechanical direct connection deceleration mode, power can be transmitted to the output shaft 5 without power conversion, or the amount of power transmitted with power conversion can be reduced. Therefore, the power transmission efficiency at low speed and high load can be improved, and the durability of the electric system can be improved and the motor generators 2 and 3 can be downsized to reduce the overall configuration of the hybrid drive device. Can do.

  Further, when the engine torque increases in the state where the mechanical direct connection deceleration mode is set, the output torque of the second motor / generator 3 is reduced accordingly. This control can be performed by the electronic control device 12 described above, and therefore the electronic control device 12 corresponds to the motor generator control means of the present invention. When the engine torque increases in this way, the torque transmitted from the power distribution mechanism 4 to the output shaft 5 increases. Therefore, even if the output torque of the second motor / generator 3 is reduced, the driving torque of the vehicle is sufficiently increased. Can be secured. Further, since the torque input to the transmission mechanism 6 is reduced by reducing the output torque of the second motor / generator 3, the transmission mechanism 6 can be downsized. The control of the increase in the engine torque and the decrease in the output torque of the second motor / generator 3 accompanying this increase in the load on the second motor / generator 3 such as an increase in the temperature of the second motor / generator 3, for example. It can be configured to execute when a situation to be reduced occurs.

  By the way, when engaging the clutch mechanism 8 in order to set the mechanical direct connection deceleration mode, it is preferable to perform synchronous control. This synchronization control is a control for matching the rotational speeds of the members engaged by the clutch mechanism 8. In the hybrid drive device having the configuration shown in FIG. 1, the engine rotational speed is set to the rotational speed of the second motor / generator 3. To match. Specifically, this can be performed by changing the rotation speed of the first motor / generator 2 so that the engine rotation speed matches the rotation speed of the second motor / generator 3. The control for setting the mechanical direct-coupled deceleration mode by engaging the clutch mechanism 8 and the synchronous control at that time are performed based on the command signal from the electronic control unit 12 described above. The electronic control device 12 corresponds to the second mode setting means of the present invention.

  The gear ratio in the transmission mechanism 6 described above increases when the low brake BLo is engaged, and relatively decreases when the high brake BHi is engaged. Therefore, as described above, when the vehicle speed gradually increases and the rotation speed of the second motor / generator 3 increases, in other words, when the vehicle enters a medium speed state, the low brake BLo is released and the high brake BHi is engaged. Thus, the transmission ratio in the transmission mechanism 6 may be reduced. The operating state is shown by a solid line in FIG.

  Even in this so-called medium speed mode, when the engine load increases and the rotational speed thereof increases, and when the vehicle speed increases, the rotational speeds of the motor generators 2 and 3 increase. Such a state is the same as the case where the vehicle speed and the engine load increase while the low speed gear ratio is set. Therefore, in order to increase the rate of mechanical power transmission, the mechanical direct connection deceleration mode is set. . Specifically, the clutch mechanism 8 is switched to the engaged state to connect the engine 1 and the second motor / generator 3 so as to transmit torque. In that case, the above-described synchronous control is executed to avoid or suppress the shock and output torque step accompanying the switching of the operation mode.

  FIG. 5 is a collinear diagram showing the mechanical direct-coupled deceleration mode in a state where the high speed gear ratio is set. As described above, in the mechanical direct-coupled deceleration mode, the power ratio transmitted from the engine 1 to the output shaft 5 via the power distribution mechanism 4, the second motor / generator 3, and the speed change mechanism 6 increases, and the power accompanied by power conversion is increased. Since the transmission rate is reduced, the power loss is reduced and the power transmission efficiency is improved. Further, the load on the electric system is reduced to improve the durability thereof, and the motor / generators 2 and 3 and the hybrid drive device can be miniaturized.

  When switching to the mechanical direct connection deceleration mode, the gear ratio in the transmission mechanism 6 is switched from the low speed gear ratio to the high speed gear ratio by engaging the high brake BHi instead of the low brake BLo, and then the clutch mechanism 8 is engaged. Let By doing so, the engine speed is reduced by setting the high speed gear ratio, and in this state, the second motor / generator 3 is connected. Therefore, it is possible to prevent the engine speed from increasing. The means for executing such switching of the gear ratio and the engagement of the clutch mechanism 8 in order corresponds to the second mode setting means of the present invention, which corresponds to the electronic control unit 12.

  In the hybrid drive device according to the present invention described above, when the vehicle speed further increases, the so-called overdrive state is controlled, and the rotational speed of the output shaft 5 is set to a higher rotational speed than the engine rotational speed. This is set by reducing the rotational speed of the first motor / generator 2 or by rotating it in the negative rotation direction (rotation direction opposite to the rotation direction of the engine 1). In this case, the rotation of the first motor / generator 2 in the negative direction is achieved by supplying electric power to the first motor / generator 2 to perform reverse rotation. And the electric power is the electric power obtained by making the 2nd motor generator 3 function as a generator, or the electric power of an electrical storage apparatus. Therefore, when the second motor / generator 3 is caused to function as a generator, the output split mode is set in order to suppress power circulation as much as possible and improve the overall power transmission efficiency.

  In this output split mode, part of the motive power output from the engine 1 is transmitted to the output shaft 5 and the second motor / generator 3 is driven to generate electric power with other motive power, and the first motor / generator 2 is generated with the electric power. Is an operation mode in which the power is reversed. Therefore, the output split mode is set when the rotation speed of the first motor / generator 2 is a negative rotation speed. In this output split mode, the brakes BHi and BLo in the speed change mechanism 6 are released (the speed change mechanism 6 is in a neutral state), the second motor / generator 3 and the output shaft 5 are disconnected, and the clutch mechanism 8 And the engine 1 and the second motor / generator 3 are connected to each other.

  Such release control of the brakes BHi and BLo and engagement control of the clutch mechanism 8 are executed based on a control command signal output from the electronic control unit 12, and therefore the electronic control unit 12 is the first control unit of the present invention. This corresponds to mode setting means. Further, when the clutch mechanism 8 is engaged to set the output split mode, the synchronous control is executed in the same manner as the case of setting the mechanical direct coupling deceleration mode described above, and the shock and output torque associated with the switching of the operation mode are executed. It is preferable to avoid or suppress the step. The synchronization control can be executed by a command signal from the electronic control unit 12 as in the case described above. Further, when switching to the output split mode, the speed change mechanism 6 is set to the neutral state with the rotation speed of the first motor / generator 2 being zero or close to zero, and then the rotation of the second motor / generator 3 and the engine is synchronized. When this occurs, the clutch mechanism 8 is engaged to switch to the output split mode. By doing so, the clutch mechanism 8 is engaged in a state where the torque of the second motor / generator 3 is small, so that the switching shock and the step of the output torque can be suppressed.

  The operation state in the output split mode at the time of high-speed cruise is shown in an alignment chart in FIG. In this state, the engine 1 and the second motor / generator 3 rotate as a unit, while the first motor / generator 2 performs reverse rotation and the sun gear Sf connected thereto rotates in reverse. As a result, the ring gear Rf and the output shaft 5 connected thereto rotate forward at a higher speed than the engine 1. That is, it becomes an overdrive state. Therefore, even if the second motor / generator 3 functions as a generator, the rotation speed thereof is the same as the engine rotation speed, and does not become a particularly high rotation speed. The rotation speed and output torque of the generator 2 may be low and low. That is, the amount of power transmission accompanied by power conversion is reduced, and the ratio of so-called mechanically transmitted power is increased, so that power transmission efficiency is improved.

  This will be described in comparison with a hybrid drive device that does not include the clutch mechanism 8. If the output split mode is not set during high-speed cruising, the second motor generator is generated as shown in the collinear diagram of FIG. 3 is rotated forward at high speed to generate electric power, and the electric power is supplied to the first motor / generator 2 to perform reverse power running, and the power is transmitted from the power distribution mechanism 4 to the output shaft 5. Therefore, power circulation occurs and power loss increases. On the other hand, in the hybrid drive device according to the present invention, the output split mode is set to distribute (or divide) the output of the engine 1 to the output shaft 5 and the second motor / generator 3, and this is output to the output shaft 5. Therefore, power circulation does not occur, and as a result, power transmission efficiency or energy efficiency is improved.

  This is illustrated in FIG. FIG. 8 shows the result of calculating the power transmission efficiency by performing simulation for the present invention example in which the output split mode and the mechanical direct connection deceleration mode can be set, and the comparative example in which the output split mode and the mechanical direct connection deceleration mode cannot be set. Yes. In FIG. 8, the solid line shows the power transmission efficiency in the example of the present invention, and the broken line shows the power transmission efficiency in the comparative example. As is apparent from FIG. 8, the engine 1 and the second motor / generator 3 are connected to set the output split mode at high vehicle speed, and to set the mechanical direct connection deceleration mode at high load at low and medium speeds. As a result, the transmission efficiency of power can be improved more than before, and the fuel consumption of the vehicle can be improved. In FIG. 8, “●” marks indicate the power transmission efficiency in the mechanical direct-coupled deceleration mode.

  Also, in the configuration where the output split mode cannot be set, the amount of power transmission accompanied by the conversion to electric power increases, so the electrical load is large, which reduces the durability of the electrical system, or the configuration has a large capacity. There is a possibility of becoming larger or larger. On the other hand, in the hybrid drive device according to the present invention, since the electric load is small, the motor generators 2 and 3 can be downsized and the durability of the electric system can be improved.

  Further, as described above, the clutch mechanism 8 is constituted by a meshing engagement mechanism, and in the output split mode set at a high vehicle speed, the transmission mechanism 6 is set to the neutral state. Power is not particularly consumed to maintain the state of transmission, and power transmission efficiency can be improved in this respect as well.

It is a skeleton figure which shows typically an example of the hybrid drive device concerning this invention. It is a skeleton figure which shows typically an example of the transmission mechanism. It is an alignment chart for demonstrating the operation state in the state which has released the clutch mechanism. It is a collinear diagram for demonstrating the operation state by the machine direct connection deceleration mode at the time of low speed and high load. It is a collinear diagram for demonstrating the operation state by the machine direct connection deceleration mode at the time of medium-speed high load. It is an alignment chart for demonstrating the operation state in output split mode. It is an alignment chart which shows a power circulation state. It is a diagram which shows power transmission efficiency about the example of this invention, and a comparative example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine (engine), 2 ... 1st motor generator, 3 ... 2nd motor generator, 4 ... Power distribution mechanism, 5 ... Output shaft, 6 ... Transmission mechanism, 8 ... Clutch mechanism, 12 ... Electronic control apparatus Cf, C ... carrier, Sf, S1, S2 ... sun gear, Rf, R ... ring gear, BHi ... high brake, BLo ... low brake.

Claims (13)

An internal combustion engine, a first motor generator, and an output member are connected to a power distribution mechanism that performs a differential action by at least three rotating elements, and the output member is capable of setting at least two high and low gear ratios. In the hybrid drive device connected to the output side and having the second motor generator connected to the input side of the speed change mechanism,
A hybrid drive apparatus further comprising a clutch mechanism for selectively connecting the internal combustion engine and the second motor generator. The transmission mechanism is configured to be able to set a neutral state in which torque is not transmitted, and by connecting the internal combustion engine and the second motor generator by engaging the clutch mechanism, the transmission mechanism is neutral. The hybrid drive apparatus according to claim 1, further comprising first mode setting means for setting an output split mode to be set.   The first mode setting means includes means for setting the output split mode when the rotation speed of the first motor generator is a negative rotation speed opposite to the rotation direction of the internal combustion engine. The hybrid drive device according to claim 2.   The first mode setting means sets the transmission mechanism in a neutral state when the rotation speed of the first motor generator is equal to or less than a predetermined rotation speed close to zero, and in that state, the internal combustion engine and the second motor generator 4. The hybrid drive device according to claim 2, further comprising means for switching the clutch mechanism to an engaged state after the rotation speed is synchronized.   The engine further includes start control means for bringing the speed change mechanism into a neutral state while the internal combustion engine is stopped and engaging the clutch mechanism, and rotating the internal combustion engine with the second motor generator in that state. The hybrid drive device according to claim 1, wherein the hybrid drive device is provided.   A second mode setting means for setting the transmission mechanism to a deceleration state capable of transmitting torque, and setting a mechanical direct coupling deceleration mode for coupling the second motor generator to the internal combustion engine with the clutch mechanism engaged; The hybrid drive device according to claim 1, wherein the hybrid drive device is provided.   The hybrid drive apparatus according to claim 6, wherein the second mode setting means includes means for setting the mechanical direct-coupled deceleration mode when a load on at least one of the motor generators is relatively large. .   The hybrid according to claim 6 or 7, wherein the second mode setting means includes means for switching to the mechanical direct-coupled deceleration mode after switching the speed ratio of the speed change mechanism from a low speed speed ratio to a high speed speed ratio. Drive device.   9. The motor generator control means for reducing the output torque of the second motor generator when the output torque of the internal combustion engine increases in the mechanical direct connection deceleration mode. The hybrid drive device according to any one of the above.   The second mode setting means includes means for engaging the clutch mechanism when the rotational speeds of the internal combustion engine and the second motor generator are synchronized when setting the mechanical direct connection deceleration mode. A hybrid drive apparatus according to any one of claims 6 to 9.   The first motor generator, the power distribution mechanism, and the second motor generator are disposed on the same axis, and the power distribution mechanism is disposed between the first motor generator and the second motor generator. The hybrid drive device according to claim 1, wherein the hybrid drive device is provided.   The clutch mechanism is constituted by a meshing dog clutch mechanism, and the speed change mechanism includes a friction type engagement mechanism that can be switched to an engagement state and a release state in order to set the respective gear ratios. The hybrid drive apparatus according to claim 1, wherein the hybrid drive apparatus is characterized in that: The power distribution mechanism is constituted by a planetary gear mechanism having a sun gear, a ring gear, and a carrier as rotating elements, and the internal combustion engine is connected to any rotating element in the planetary gear mechanism, and the first motor generator Is connected to another rotating element, and the output member is further connected to another rotating element,
13. The clutch mechanism according to claim 1, wherein the clutch mechanism is configured to selectively connect the rotating element to which the internal combustion engine is connected and the second motor generator. Hybrid drive device.

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