JP2011098706A - Shift control device for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent shock when the start of an engine is overlapped with the release of a parking lock. <P>SOLUTION: A shift control device is provided for a hybrid vehicle having an output member for outputting torque output from the engine to driving wheels, a parking mechanism for suspending the rotation of the output member when a parking position is selected, and a motor for supplying torque to a transmission mechanism relative to the driving wheels. The shift control device includes: a torque correction means for increasing and correcting the motor output torque to reduce the torque functioning to the parking mechanism by means of twist torque stored in the transmission mechanism, prior to the release of locking the output member (step S3); a lock release means for releasing the lock stopping the rotation of the output member while the motor output torque is being increased and corrected (step S4); and a torque correction restoration means for restoring the torque to the state prior to the increase and the correction, by gradually decreasing the increase correction amount of the motor output torque after the lock of the output member is released (step S5). <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hybrid vehicle provided with an electric motor as a driving force source, and more particularly to a shift control device that performs control when shifting from a parking position where the vehicle is maintained in a stopped state to another position.

  A vehicle equipped with a speed change mechanism capable of controlling a gear ratio electrically or hydraulically is configured to select a stop state, a forward travel state, a reverse travel state, or the like by a shift device. This type of shift device is provided with a plurality of positions selected by a shift lever, a switch, etc., and the driver selects those positions so that the vehicle is set to an appropriate driving state or traveling state. It has become. In particular, when a parking position for maintaining the vehicle in a stopped state is selected, the output shaft of the speed change mechanism is forcibly fixed, and the rotation of the drive wheels is stopped. Conventionally known.

  The parking mechanism is configured to stop the rotation of the output shaft in the speed change mechanism. As an example, a parking gear is attached to the output shaft or a member integral therewith, and a lock pawl is engaged with the parking gear. Thus, a mechanism configured to fix the parking gear and the output shaft integral with the parking gear is known. Therefore, a transmission member such as a propeller shaft, a shaft coupling, or a final reduction gear is interposed between the parking gear and the drive wheel. Therefore, for example, when torque is applied to the drive wheels by the inertia force of the vehicle while the output shaft is stopped by the parking gear, the transmission member is twisted, and the vehicle is maintained in the stopped state in that state. The That is, the vehicle is in a state where torsional torque is stored. As a result, when the vehicle is shifted from the parking position to another position such as the drive position in order to run the vehicle again, the parking gear is unfixed, and the accumulated torsional torque causes the gears in the transmission member and the transmission mechanism to move. Rotation occurs, and so-called rattling noise and shock may occur.

  Therefore, Patent Document 1 proposes an invention that aims to reduce the engagement load between the parking gear and the parking pole when the parking lock is released. In the invention described in Patent Document 1, a motor is provided between the parking gear and the driving wheel, and when the parking is released, the driving wheel is first restrained so as to prevent the driving wheel from rotating, and the parking is performed in that state. By driving the motor so as to cause torsion between the gear and the drive wheel, the engagement load between the parking gear and the parking pole is reduced, and further, the restraint of the drive wheel is loosened and the distance between the motor and the drive wheel is reduced. The torsion is reduced to reduce the engagement load between the parking gear and the parking pole.

  Further, in Patent Document 2, when the parking mechanism is engaged with the parking gear and the vehicle is set to the stop state, the parking gear is reliably engaged by rotating the parking gear by a predetermined angle by the motor / generator in the hybrid device. An apparatus configured to do is described.

  In Patent Document 3, in a hybrid vehicle, when the parking position is changed to the neutral position during engine start control or stop control, the stepped transmission unit is operated until the engine start or stop control ends. An apparatus is described that is configured to maintain the rotational speed of the input shaft at a predetermined rotational speed by a motor generator.

JP 2008-51313 A JP 2006-81264 A JP 2009-149133 A

  In the invention described in Patent Document 1, the torsion torque acting between the parking gear and the parking pole or a part of the torque is applied to the motor. It is configured to reduce the torsional torque stored in the transmission mechanism. Therefore, it is necessary to install an additional motor between the parking gear and the drive wheel, increasing the number of parts and complicating the configuration. The problem arises. Further, in a hybrid vehicle or the like configured such that the reaction force accompanying the start of the engine acts on the parking gear, when the control described in Patent Document 1 is executed, the torque control is not considered in consideration of the reaction force. , Shock can occur.

  The invention described in Patent Document 2 is an invention configured to control the motor / generator when the parking gear is locked, and thus eliminates a shock, rattling sound and the like when the lock is released. It doesn't work in particular. Furthermore, the device described in Patent Document 3 uses a motor / generator to adjust the rotational speed of the input shaft of the stepped transmission unit so that the shift from the parking position to the neutral position does not affect the startability or stopability of the engine. Therefore, it is difficult to reduce or prevent the torque change caused by unlocking the parking gear or the accompanying shock and rattling noise.

  The present invention has been made paying attention to the above technical problem, and in a hybrid vehicle equipped with an electric motor as a driving force source, a new component member is added such as a shock or rattling sound when the parking lock is removed. It is an object of the present invention to provide a device that can be prevented or reduced.

  In order to achieve the above object, the invention according to claim 1 is an engine, and an output member that outputs a torque output from the engine to a drive wheel while a reaction force acts when the engine is started. A parking mechanism that stops rotation of the output member when a parking position is selected; and an electric motor that applies torque to a transmission mechanism between the parking mechanism and the drive wheel. In the shift control device for a hybrid vehicle configured to cause the electric motor to output a torque that counteracts a reaction force associated with starting the engine when the engine is started in a state where the rotation is stopped. The output member is locked by the parking mechanism in accordance with the shift to the shift position. Prior to releasing the torque, the torque correction means for increasing the output torque of the motor so as to reduce the torque acting on the parking mechanism by the torsional torque accumulated in the transmission mechanism, and the torque correction Unlocking means for unlocking the rotation of the output member by the parking mechanism while the output torque of the electric motor is increased and corrected by the means, and after the output member is unlocked by the unlocking means, Torque correction return means for gradually decreasing the increase correction amount of the output torque of the electric motor is provided.

  According to a second aspect of the present invention, in the first aspect of the present invention, the torque correction means uses a torque equal to the estimated value of the torsional torque when the parking position is selected as an increase correction amount for the output torque of the motor. A shift control apparatus for a hybrid vehicle characterized by comprising means for

  According to a third aspect of the present invention, in the first or second aspect of the invention, when the increase of the output torque of the electric motor cannot be corrected by the torque correction means during the start of the engine, the start of the engine is stopped. The hybrid vehicle shift control device is configured to release the lock of the driving wheel by the parking mechanism after completion.

  The invention of claim 4 is the invention according to any one of claims 1 to 3, wherein the input element to which the engine is connected, the output element to be the output member, and the generator motor are connected. A shift control apparatus for a hybrid vehicle, further comprising a differential mechanism that performs a differential action by three rotating elements with a force element.

  According to the first or second aspect of the invention, when starting the engine, a torque that counteracts the reaction force acting on the output member is applied to the output member by the electric motor, and the torsional torque acting on the parking mechanism is applied. A decreasing torque is applied to the output member. Therefore, even if the output member is locked by the parking mechanism, the torque caused by the torsional torque does not act on the output member greatly. In particular, according to the invention of claim 2, the torsional torque is received by the electric motor. Since it does not act on the output member, it is possible to prevent or reduce shock and rattling noise. Naturally, in this case, the reaction force accompanying the start of the engine is handled by the electric motor, so that it does not hinder the start of the engine. Further, after the output member is unlocked by the parking mechanism, the torque for the increase correction of the motor is gradually reduced, so that a sudden change in the torque related to the output member is avoided. And rattling noise can be prevented or suppressed.

  According to the invention of claim 3, when the increase correction of the output torque of the electric motor described above cannot be performed, the output member is locked by the parking mechanism after the start of the engine is completed. It is possible to avoid unlocking in a state where the reaction force and torsional torque that are applied are superimposed, and as a result, the engine startability is not impaired, Aggravation of rattling noise can be avoided.

  According to the invention of claim 4, it is possible to achieve both engine startability in a so-called two-motor hybrid vehicle and avoidance of shock and rattling noise when the parking lock is released.

It is a flowchart for demonstrating an example of the control performed with the control apparatus of this invention. It is a figure which shows an example of the map which defined the relationship between the rotation variation | change_quantity of a 2nd motor generator, and a twist torque. 2 is a time chart schematically showing changes in torque of each motor / generator and engine speed when the control shown in FIG. 1 is executed. It is a flowchart for demonstrating the example of control which loosens with a 2nd motor generator before releasing a parking gear. It is a schematic diagram which shows an example of the drive system of the hybrid vehicle made into object by this invention. It is a collinear diagram about the planetary gear mechanism which comprises the power distribution mechanism, Comprising: It is a collinear diagram which shows the state at the time of engine starting.

  Next, the present invention will be described more specifically. The hybrid vehicle that is the subject of this invention is equipped with an engine and an electric motor. The engine is basically a heat engine that burns fuel and outputs mechanical power, such as a gasoline engine, diesel engine, or gas. An example is a gas engine that uses fuel. The electric motor is supplied with electric power and outputs a torque for traveling. In the present invention, the electric motor is arranged so as to receive a reaction force particularly when the engine is started. That is, the electric motor is connected to an output member that outputs torque output from the engine to the drive wheels.

  FIG. 5 schematically shows an example of this, and the example shown here is an example of a vehicle equipped with a so-called two-motor type hybrid device. In FIG. 5, the output shaft 2 of the engine 1 is connected to a power distribution mechanism 4 via a clutch 3. The power distribution mechanism 4 is a so-called differential mechanism configured to perform a differential action by three rotating elements, and these three rotating elements are gears and rollers. In the example shown in FIG. 5, the power distribution mechanism 4 is configured by a planetary gear mechanism. Therefore, the power distribution mechanism 4 includes a sun gear 5 that is an external gear and an inner ring that is arranged concentrically with respect to the sun gear 5. A ring gear 6 that is a toothed gear and a carrier 7 that is arranged between the sun gear 5 and the ring gear 6 and supports the pinion gear meshing with the sun gear 5 and the ring gear 6 so as to be able to rotate and revolve as rotation elements. I have.

  The aforementioned output shaft 2 of the engine 1 is connected to the carrier 7 via the clutch 3, and the sun gear 5 is connected to the first motor / generator (MG 1) 8. The first motor / generator 8 is a permanent magnet type AC synchronous motor as an example, corresponds to the generator motor in the present invention, and is connected to the power storage device 10 via the inverter 9. The first motor / generator 8 is configured to function as a motor when electric power is supplied from the power storage device 10 and to generate power by forcibly rotating to charge the power storage device 10. ing.

  Note that the rotor shaft of the first motor / generator 8 is a hollow shaft, and the carrier shaft 11 penetrates through the inside thereof. One end of the carrier shaft 11 is connected to the carrier 7 described above, and the other end protruding from the rotor shaft is connected to a mechanical oil pump (MOP) 12.

  Furthermore, a parking gear 13 is integrated with the ring gear 6 that is an output member. The parking gear 13 is for fixing the ring gear 6 when a parking position is selected by a shift device (not shown), and constitutes a part of the parking mechanism. The parking mechanism may have the same configuration as that conventionally known. For example, when a parking position is selected by a switch operation by a driver, a link mechanism or an actuator (not shown) is operated. The parking lock pole 14 is configured to mesh with the parking gear 13.

  An output shaft 15 is rotatably fitted to the carrier shaft 11 that connects the above-described member on the output side of the clutch 3 and the carrier 7, and the output shaft 15 is connected to the ring gear 6. Have been integrated. A counter gear 16 is attached to the output shaft 15, and a counter driven gear 17 is engaged with the counter gear 16. The counter driven gear 17 is attached to a counter shaft 18 that is disposed in parallel and rotatably with the carrier shaft 11, and an output gear 19 is further attached to the counter shaft 18. It meshes with the ring gear 20. The differential ring gear 20 is a gear integrated with a differential case of a differential gear 21 that is a final reduction gear, and is thus configured to transmit drive torque from the differential gear 21 to the left and right drive wheels 22.

  Furthermore, a second motor / generator 23 is provided for applying torque to the transmission mechanism between the parking gear 13 and the drive wheel 22 described above. This second motor / generator (MG2) 23 corresponds to the electric motor in the present invention, and is constituted by a permanent magnet type AC synchronous motor as an example, similar to the first motor / generator 8 described above. The power storage device 10 is connected. The second motor / generator 23 is connected to the drive gear 25 meshed with the counter driven gear 17 described above. Therefore, the output torque of the second motor / generator 23 is converted to the drive gear 25, the counter driven gear 17, and the output gear. The torque is transmitted to the differential gear 21 via 19 and from here to the left and right drive wheels 22. Since the differential ring gear 20 has a larger diameter than the output gear 19, the gear mechanism from the second motor / generator 23 to the differential gear 21 constitutes a speed reduction mechanism.

  An electronic control unit (ECU) 26 is provided for controlling the engagement / release of the clutch 3, control of locking and releasing by the parking mechanism, control of the inverters 9 and 24, and the like. The electronic control unit 26 is mainly composed of a macro computer, and based on various input signals such as a vehicle speed, an accelerator opening, a brake operation signal, a shift position signal, etc., the clutch 3, the parking mechanism, each inverter 9, The control command signal is output to 24 or the like.

  Here, the operation of the hybrid device will be briefly described. When a so-called positive torque is transmitted to the carrier 7 by the engine 1, the ring gear 6 is loaded by a running resistance of the vehicle, and therefore the sun gear 5 A so-called positive direction torque acts on. When reaction torque is generated by the first motor / generator 8 so as to counter the so-called positive torque in the sun gear 5, that is, the first motor / generator 8 functions as a generator to reduce the rotational speed of the sun gear 5. When torque is generated, torque in a direction in which the ring gear 6 serving as an output member rotates in the forward direction appears. The torque is transmitted from the counter gear 16 described above to the left and right drive wheels 22 via the differential gear 21. In that case, the rotational speed of each rotating element constituting the power distribution mechanism 4 is a rotational speed determined according to the gear ratio of the planetary gear mechanism (ratio between the number of teeth of the sun gear and the number of teeth of the ring gear). By appropriately controlling the rotational speed of the first motor / generator 8, the rotational speed of the engine 1 can be controlled to the most efficient rotational speed, that is, the rotational speed at which the fuel consumption is optimized.

  On the other hand, the electric power generated by the first motor / generator 8 is supplied to the second motor / generator 23, and the second motor / generator 23 functions as a motor to apply torque to the drive wheels 22. That is, a part of the motive power output from the engine 1 is once converted into electric power, then converted again into drive torque via the second motor / generator 23 and transmitted to the drive wheels 22. When the vehicle travels backward, the driving wheel 22 is driven in a so-called reverse rotation direction by operating the second motor / generator 23 as a motor in a direction opposite to that when traveling forward with the clutch 3 released. Torque is transmitted. Therefore, the vehicle travels backward by the second motor / generator 23.

  Further, motoring (cranking) for starting the engine 1 is performed by driving the first motor / generator 8. In other words, the engine 1 can be started when the parking position is selected. Therefore, the sun gear 5 is fixed to the first motor and the ring gear 6 with the parking mechanism fixed. A so-called forward rotation is performed by the generator 8. FIG. 6 is a collinear diagram of the planetary gear mechanism constituting the power distribution mechanism 4 in this state.

  The collinear diagram shown in FIG. 6 is a collinear diagram for a single pinion type planetary gear mechanism, and three straight lines showing the sun gear 5, the ring gear 6 and the carrier 7 are drawn in parallel to each other, and the line showing the sun gear 5 is shown. A line indicating the carrier 7 is arranged between the line indicating the ring gear 6 and the line indicating the sun gear 5 and the line indicating the carrier 7 is “1”, and the line indicating the carrier 7 and the ring gear 6 are indicated. The distance from the line is equal to the gear ratio of the planetary gear mechanism. The length above the base line orthogonal to these lines indicates the rotational speed in the positive rotation direction, and the length on the lower side indicates the rotational speed in the negative rotation direction. Therefore, the base line is a line indicating that the rotational speed is “0”. When the engine 1 is started, the ring gear 6 is fixed and the rotational speed is “0”. When the sun gear 5 is rotated forward by the first motor / generator 8 in this state, the ring gear 6 is above the base line in the line indicating the sun gear 5. A straight line connecting the point of the predetermined rotational speed and the intersection of the line indicating the ring gear 6 and the base line indicates the operating state of the planetary gear mechanism. Therefore, the rotational speed of the carrier 7 and the engine 1 connected thereto is determined. And the rotational speed represented by the intersection of the straight line and the line indicating the carrier 7. Thus, when the engine 1 is started, if the ring gear 6 is fixed and a positive torque is applied to the sun gear 5 from the first motor / generator 8, the carrier 7 and the engine 1 connected thereto are rotated forward, If fuel is supplied to the engine 1 and ignited in this state, the engine 1 can be rotated independently.

  By the way, the above-described operation for starting the engine 1 and the shift operation for releasing the locking (locking) of the drive wheels 22 by the parking mechanism are operations independent of each other, and can be performed simultaneously. For example, during the start control of the engine 1, there is a case where the parking position is switched to another shift position such as a neutral position. In such a case, in addition to the torque transmitted from the second motor / generator 8 so as to counter the reaction force accompanying the start of the engine 1, the transmission member from the parking mechanism to the drive wheels 22 is applied to the ring gear 6. The torsional torque accumulated in the torque acts, and a change in torque is caused by releasing the torsional torque, which may cause vibration and noise such as shock and rattling noise. The shift control device according to the present invention is configured to smoothly release the parking lock during such start control of the engine 1. An example of the control for that will be described with reference to the flowchart shown in FIG.

  The routine shown in FIG. 1 is configured to be executed in a state where the rotation of the ring gear 6 (drive wheel 22), which is an output member, is stopped by the parking mechanism described above and the engine 1 is stopped. It is determined whether or not the engine (E / G) 1 is being started (step S1). This determination can be made by determining whether a switch (not shown) for starting the engine 1 is turned on or whether a request signal for starting the engine 1 is generated. it can. Alternatively, the first motor / generator 8 operates as a motor so as to crank the engine 1, and it can be determined by determining whether torque is output.

  If the engine 1 is not being started and the determination is negative in step S1, the routine returns without performing any particular control. Alternatively, normal control for unlocking the parking mechanism is executed after the start of the engine 1 is completed. On the contrary, if the determination in step S1 is affirmative because the engine 1 is being started, it is determined whether or not there is a request to release the parking (P) gear (step S2). In the hybrid vehicle having the configuration shown in FIG. 5, a parking gear release request is established by operating a parking release switch (not shown) or by shifting the shift lever to a shift position other than the parking position, and the request signal is output. It is comprised so that. Therefore, the determination in step S2 can be made by detecting whether or not the request signal is output. If a negative determination is made in step S2 because there is no parking gear release request, the routine returns without performing any control, or normal control is executed.

  On the other hand, if a positive determination is made in step S2 due to a request to release the parking gear, torque correction control of the second motor / generator 23 corresponding to the electric motor in the present invention is executed (step S3). ). As described above, the engine 1 is started by operating the first motor / generator 8 as a motor and cranking the engine 1. Therefore, as described with reference to FIG. Is exerted by the second motor / generator 23 to counteract this. Further, when the parking lock is released during the start of the engine 1, the second motor / generator 23 is configured so that the second motor / generator 23 receives all or a part of the torsion torque acting on the parking gear 13. Increase the torque. The increase in the torque of the second motor / generator 23 based on the torsional torque is the torque correction in step S3.

  Therefore, in this torque correction control, the torsion torque is obtained. The torsional torque is transmitted when the torque is transmitted to the drive wheels 22 and the parking gear 13 is locked and the vehicle is stopped in a state where the torque is transmitted in the torque transmission path. This occurs when the torsional torque acts on the torque transmission path due to the inertial force of the vehicle after the gear 13 is locked, and the vehicle stops in that state. For this reason, the torsion according to the torsion torque is generated in the transmission mechanism or transmission member between the parking mechanism and the drive wheel 22, and therefore the rotation angle of the second motor / generator 23 connected to the transmission mechanism or transmission member. The torsional torque can be obtained based on For example, the rotation angle of the second motor / generator 23 when the parking gear 13 is engaged or requested at the previous time, and the rotation angle of the second motor / generator 23 when the unlocking request of the parking gear 13 is requested this time. Torsional torque is obtained by multiplying the rotational change amount of the second motor / generator 23 by the torsional elastic coefficient of the transmission mechanism or transmission member and a predetermined constant determined by the mechanism and the rotational change amount. . Alternatively, the relationship between the rotation change amount of the second motor / generator 23 and the torsion torque is prepared in advance as a map, and the torsion torque can be obtained based on the map. An example of such a map is shown in FIG. The example shown in FIG. 2 is an example in which the amount of rotation change of the second motor / generator 23 is proportional to the torsion torque.

  When the output torque of the second motor / generator 23 is increased and corrected as described above, the second motor / generator 23 takes charge of the reaction force accompanying the start of the engine 1 and the torsional torque generated in the transmission mechanism or transmission member. Thus, torque applied to the parking gear 13 (engagement force between the parking gear 13 and the parking lock pole 14) is reduced. In this state, the parking gear 13 is unlocked (step S4). Specifically, the parking lock pole 14 is rotated or moved in a direction away from the parking gear 13. In that case, since the torsional torque is carried by the second motor / generator 23, there is little or no change in torque associated with the unlocking of the parking gear 13, and therefore a large shock or rattling sound (or gear) No rattling noise).

  Subsequently, correction return control is performed to return the output torque of the second motor / generator 23 corrected for increase to the torque before correction (step S5), and the process returns. The correction return control is a control for gradually reducing the output torque of the second motor / generator 23. The decreasing gradient is a gradient at which the change in the drive torque at the drive wheels 22 is not felt as a shock, or the rattling. The gradient is such that the sound (or the gear rattling sound) does not feel uncomfortable, and this can be set in advance by experiment or simulation. Moreover, the decreasing tendency may be one in which the decreasing gradient changes with the passage of time, in addition to the uniform decreasing.

  FIG. 3 is a time chart showing a change in torque and a change in engine speed when the control for releasing the parking lock is executed during the start of the engine 1 described above. When the engine 1 is stopped and the engine 1 is requested to start at a predetermined time t1 while the vehicle is maintained in a stopped state by the parking mechanism, the first motor / generator 8 functions as a motor and functions as a so-called forward direction. The second motor / generator 23 is controlled to output a positive torque that counteracts the reaction force caused by the first motor / generator 8 increasing the rotational speed of the engine 1. . The torque to be output by these motor generators 8 and 23 is a predetermined torque. When each motor / generator 8, 23 outputs a positive torque as described above, the engine 1 is rotated in the forward direction, and the number of rotations gradually increases.

  If there is a request to release the parking gear 13 at time t2 in the process of increasing the rotational speed of the engine 1, the output torque of the second motor / generator 23 is corrected to increase. As described above, the increase correction amount is an amount corresponding to the torsion torque generated in the transmission mechanism or the transmission member, or an amount obtained based on the torsion torque. After the output torque of the second motor / generator 23 is corrected to increase in this way, the parking gear 13 is unlocked (at time t3). Next, the output torque of the second motor / generator 23 is gradually reduced toward the torque before the increase correction. After the parking gear 13 is released in this way, the engine 1 reaches a so-called complete explosion state (at time t4). That is, the start of the engine 1 and the release of the parking lock are completed. As a result, the first motor / generator 8 is controlled so as to function as a generator, and controls the rotational speed of the engine 1 to a rotational speed based on the current output request such as the idling rotational speed. The second motor / generator 23 receives electric power from the first motor / generator 8 and functions as a motor.

  The above specific example is an example of correcting the increase in the output torque of the second motor / generator 23 before the complete explosion of the engine 1, but the timing at which the torsion torque is completely released is the complete explosion of the engine 1. In the latter case, the same increase correction as in the above-described example may be performed on the torque required for the second motor / generator 23 after the complete explosion of the engine 1.

  Further, in the control according to the present invention, the output torque of the second motor / generator 23 is increased and corrected. For this purpose, it is necessary to output electric power from the power storage device 10. Therefore, there is a case where the torque increase correction of the second motor / generator 23 cannot be performed on the power storage device 10 by the charge capacity (SOC). In such a case, even if there is a request to release the parking gear 13 during the start control of the engine 1, the release of the parking gear 13 is delayed until after the complete explosion of the engine 1. A shift control apparatus provided with means for performing such delay control is an example of the invention according to claim 3.

  By the way, the shock and rattling noise associated with the release of the parking lock may be caused by clogging of the clearance (backlash) between components in the transmission mechanism or transmission member. Therefore, shock or rattling noise can be prevented or reduced by performing so-called rattling prior to unlocking the parking gear 13. An example in which such control is performed using the second motor / generator 23 is shown in the flowchart of FIG.

  The control example shown in FIG. 4 is configured to be executed in a state where the engine 1 is stopped and the parking gear 13 is locked and the vehicle is stopped. First, the parking (P) gear release request It is determined whether or not there is (step S11). This is a determination step similar to step S2 in the control example shown in FIG. If a negative determination is made in step S11, the process returns without performing any particular control. On the other hand, if a positive determination is made in step S11 due to a request to release the parking gear 13, the torsional torque generated in the transmission mechanism or transmission member from the parking mechanism to the drive wheel 22 is estimated. (Step S12). The estimation can be performed based on the rotation change amount of the second motor / generator 23 using the map shown in FIG. 2 as described above, or can be performed based on a predetermined value.

  Next, the torque and rotation direction of the second motor / generator 23 are controlled (step S13). In the hybrid vehicle configured as shown in FIG. 5 described above, the second motor / generator 23 is connected to the drive wheel 22 via the drive gear 25 attached to the output shaft and the counter driven gear 17 meshed with the drive gear 25 or the like. Since it is connected to the ring gear 6, the torque acts on the second motor / generator 23 by releasing the torsional torque. Therefore, before the parking gear 13 is unlocked, the second motor / generator 23 is operated as a motor so that torque is applied from the drive gear 25 to the counter driven gear 17 so that the backlash is reduced. Therefore, the direction of the torque is the torque in the direction in which the backlash occurs in the direction in which the tooth contact occurs when the torsional torque is released. The magnitude of the torque depends on the magnitude of the torsional torque. That is, when the parking gear 13 is released and the torsional torque is released, if the second motor / generator 23 is easily rotated by the torsional torque, the torque change becomes abrupt and causes a shock. The output torque of the second motor / generator 23 is set to a torque corresponding to the torsional torque so that the torsional torque is received by the two-motor / generator 23 to some extent. Thus, after setting the torque of the second motor / generator 23 in step S13, the parking gear 13 is unlocked (step S14).

  Therefore, if the control shown in FIG. 4 is executed, when the parking gear 13 is unlocked, the torsion torque generated in the transmission mechanism or transmission member is received by the second motor / generator 23 instead of the parking gear 13. In this case, since the play is already clogged, there is no loud rattling sound (tooth rattling sound) and no big shock is generated.

  Here, the relationship between the above-described specific example and the present invention will be briefly described. The functional means for executing step S3 described above corresponds to the torque correcting means in the present invention, and the functional means for executing step S4. However, this corresponds to the unlocking means of the present invention, and the functional means for executing step S5 corresponds to the torque correction return means of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Engine, 4 ... Power distribution mechanism, 5 ... Sun gear, 6 ... Ring gear, 7 ... Carrier, 8 ... 1st motor generator (MG1), 10 ... Power storage device, 13 ... Parking gear, 14 ... Parking lock pole, 15 ... output shaft, 16 ... counter gear, 17 ... counter driven gear, 18 ... counter shaft, 19 ... output gear, 20 ... diff ring gear, 21 ... differential gear, 22 ... drive wheel, 23 ... second motor / generator, 26 ... electronic Control unit (ECU).

Claims (4)

An engine, an output member that reacts when starting the engine and outputs torque output by the engine to the drive wheels, and a parking that stops rotation of the output member when a parking position is selected An engine that provides torque to a transmission mechanism between the parking mechanism and the drive wheel, and the engine is started when the rotation of the output member is stopped by the parking mechanism. In a shift control device for a hybrid vehicle configured to output a torque that counteracts a reaction force accompanying starting of the motor by the electric motor,
Prior to unlocking the output member by the parking mechanism when the parking position is switched to another shift position, the torsional torque accumulated in the transmission mechanism acts on the parking mechanism. Torque correction means for increasing and correcting the output torque of the motor so as to reduce the torque
Unlocking means for releasing the lock for stopping the rotation of the output member by the parking mechanism while the output torque of the electric motor is increased and corrected by the torque correcting means;
A shift control apparatus for a hybrid vehicle, comprising: torque correction return means for gradually decreasing the increase correction amount of the output torque of the electric motor after the output member is unlocked by the unlocking means.   The torque correction means includes means for setting a torque equal to an estimated value of the torsion torque in a state where the parking position is selected as an increase correction amount of the output torque of the electric motor. Shift control device for hybrid vehicles.   If it is not possible to correct the increase in the output torque of the motor by the torque correction means during the engine start, the parking wheels are unlocked by the parking mechanism after the engine start is completed. The hybrid vehicle shift control device according to claim 1, wherein the shift control device is a hybrid vehicle.   A differential mechanism that performs a differential action by three rotating elements of an input element to which the engine is connected, an output element to be the output member, and a reaction force element to which a generator motor is connected; The hybrid vehicle shift control device according to any one of claims 1 to 3, further comprising a shift control device.

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