JP2015203456A - Fail determination device of vehicle power transmission mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To exactly determine an abnormality of a sensor which detects an operation state of an SOWC without adding new parts.SOLUTION: When a sensor outputs a signal indicating that an SOWC is brought into an engagement state during the execution of control for setting the SOWC in a release state (step S1), control (step S4) for changing a difference rotation number of a first member and a second member is performed, and according to a state (step S5) of the difference rotation number generated by a change or non-change of a state of the engagement/release of a selectable one-way clutch accompanied by the execution of control for changing the difference rotation number, the determination (steps S9, S10) of an abnormality of the sensor is performed.

Description

  The present invention relates to an apparatus for determining a failure (abnormality) occurring in a mechanism for transmitting power for traveling of a vehicle.

  An example of a power transmission mechanism for a vehicle is described in Patent Document 1. The mechanism described in Patent Document 1 is a transmission for a vehicle including a selectable one-way clutch (hereinafter referred to as SOWC). The SOWC includes a strut plate and a notch plate formed in an annular shape, respectively. The strut plate is disposed on the same axis, and a plurality of struts protruding to the notch plate side by a spring are arranged side by side in the circumferential direction. The slide plate has an opening for allowing the strut to pass therethrough, corresponding to the strut. Further, the notch plate is formed with a plurality of notches that are inserted in the front end of the strut and engaged in a predetermined rotational direction so as to correspond to the strut in the circumferential direction. Then, the strut is pushed into the pocket formed in the strut plate by rotating or moving the slide plate by the actuator and shifting the phase of the opening and the strut. As a result, the strut plate and the notch plate The engagement (that is, connection) is released, and the strut plate and the notch plate can rotate relative to each other in both the positive rotation direction and the negative rotation direction. Further, when the position of the opening of the slide plate coincides with the strut, the strut passes through the opening and protrudes toward the notch plate, and the tip of the strut enters the notch. As a result, the strut plate and the notch plate are fixed to each other. Engage in the rotational direction (hereinafter referred to as the positive rotational direction), and torque is transmitted between the two. In this so-called engaged state, when a torque acts between the strut plate and the notch plate in the direction opposite to the forward rotation direction, the strut is pushed back to the strut plate side by the opening end of the notch and The engagement is released, and the strut plate and the notch plate can rotate relative to each other in the direction opposite to the positive rotation direction (hereinafter referred to as the negative rotation direction). That is, the SOWC functions as a one-way clutch in the so-called engaged state, and does not transmit torque in either the positive rotation direction or the negative rotation direction of the torque in the released state.

US Pat. No. 8,348,796

  The switching between the engaged state and the released state of the SOWC is performed by rotating the slide plate by a predetermined angle by the actuator. Since the actuator has a plunger in the example described in Patent Document 1, whether the SOWC is engaged or released by detecting the stroke of the plunger with a sensor. Can be determined.

  The sensor also outputs a signal when its own failure (failure) or SOWC failure occurs. Accordingly, for example, when a signal for engaging SOWC is output from the sensor in a state where control for releasing SOWC is being performed, it can be determined that some abnormality has occurred. However, it is not possible to determine whether the abnormality is due to a sensor failure or a SOWC failure only from the sensor output signal. In order to cope with such a situation, it is conceivable to provide a plurality of sensors and discriminate between a sensor failure and a SOWC mechanism failure based on the coincidence or mismatch of the detection signals of these sensors. However, if a plurality of sensors are provided, the cost may increase as the number of parts increases, and the overall configuration of the apparatus may increase.

  The present invention has been made paying attention to the above technical problem, and can determine the abnormality of the sensor for detecting the operating state of the SOWC in the power transmission mechanism without adding new parts. The object is to provide a control device.

  In order to achieve the above object, the present invention includes a first member and a second member, and the first member and the second member are relative to each other in the forward rotation direction at a rotation speed equal to or higher than a predetermined differential rotation speed. In the rotating state, it is not engaged, and in the forward rotation state less than the predetermined number of rotations, it switches to the engaged state to transmit torque between the first member and the second member, and what is the forward rotation direction? A selectable one-way clutch that is selectively set to an engaged state in which torque is not transmitted in the opposite negative rotation direction and a disengaged state in which torque is not transmitted in either the positive rotation direction or the negative rotation direction; A vehicle comprising: a switching operation mechanism that switches the clutch between the engaged state and the released state; and a sensor that detects an operation of the selectable one-way clutch by the switching operation mechanism. When the sensor outputs a signal indicating that the selectable one-way clutch is in an engaged state during execution of control for setting the selectable one-way clutch in the released state, in the fail determination device for the power transmission mechanism for power, The control for changing the differential rotational speed between the first member and the second member is executed, and the state of disengagement of the selectable one-way clutch is changed in accordance with the execution of the control for changing the differential rotational speed. However, it is configured to determine abnormality of the sensor in accordance with the state of change of the differential rotational speed due to the fact that it does not change.

  According to the present invention, when the selectable one-way clutch (hereinafter referred to as SOWC) is controlled to be in the disengaged state, when the sensor outputs a detection signal of the engagement state of the SOWC, the first member and the second member The differential rotation speed, which is the relative rotation speed with the member, is changed. If the differential rotational speed at the time when the sensor outputs the detection signal is equal to or greater than the predetermined differential rotational speed in the forward rotational direction, the SOWC does not switch to the engaged state, but if the differential rotational speed is decreased, the SOWC is Since it switches to an engagement state, a 1st member and a 2nd member are connected and a differential rotation speed changes suddenly. On the other hand, if the sensor outputs the detection signal by its own failure, the switching operation mechanism is not operated to bring the SOWC into the engaged state, so that even if the differential rotational speed is reduced. Since the SOWC is not engaged, the differential rotational speed does not change suddenly. The mode of change in the differential rotation speed by executing the control for changing the differential rotation speed varies depending on whether or not the sensor has failed. Therefore, according to the present invention, the sensor failure is controlled by the differential rotation speed change control. Can be reliably determined, and provision of new parts is avoided.

It is a flowchart for demonstrating an example of the control performed with the control apparatus which concerns on this invention. It is a collinear diagram about the planetary gear mechanism that constitutes the power split mechanism shown in FIG. FIG. 8 is a collinear diagram for a compound planetary gear mechanism constituting the power split mechanism and the overdrive mechanism shown in FIG. 7. It is a time chart which shows an example of a change of differential rotation speed. It is a flowchart for demonstrating the other example of the control performed with the control apparatus which concerns on this invention. It is a skeleton figure which shows an example of the power transmission mechanism which can be made into object by this invention. It is a skeleton figure which shows the other example of the power transmission mechanism which can be made into object by this invention. It is typical sectional drawing which shows the structure of the engaging mechanism in the selectable one-way clutch which can be made into object by this invention. It is a typical fragmentary figure which shows the notch currently formed in the pocket currently formed in the 1st clutch board, and the 2nd clutch board. It is a fragmentary sectional view showing a part of other selectable one-way clutch which can be targeted by the present invention. It is a figure which shows an example of a ratchet structure.

  The present invention can be applied not only to a general vehicle that uses an engine as a driving force source, but also to a control device that targets a power transmission mechanism in a hybrid vehicle that uses an engine and a motor as driving force sources. FIG. 6 schematically shows a power transmission mechanism in a double-shaft two-motor type hybrid vehicle. The engine (Eng) 1 as a driving force source and a power generation function corresponding to the motor in the present invention are shown in FIG. 1 motor (MG1) 2 and a second motor (MG2) 3 having a power generation function. The first motor 2 mainly controls the rotation speed of the engine 1 and cranks the engine 1, and the second motor 3 mainly functions as a driving force source for traveling. The first motor 2 is coupled together with the engine 1 to a power split mechanism 4 configured by a differential mechanism. Further, the torque of the second motor 3 is adjusted to the torque output from the power split mechanism 4.

  In the example shown in FIG. 6, the power split mechanism 4 is configured by a single pinion type planetary gear mechanism having the sun gear 5, the carrier 6, and the ring gear 7 as rotating elements, and the rotor of the first motor 2 is connected to the sun gear 5. The output shaft (crankshaft) of the engine 1 is connected to the carrier 6, and the ring gear 7 is an output element. An output gear 8 is attached as an output member to the ring gear 7, and the output gear 8 meshes with the counter driven gear 9. A counter drive gear 11 having a smaller diameter than the counter driven gear 9 is attached to the counter shaft 10 to which the counter driven gear 9 is attached, and the counter drive gear 11 meshes with the ring gear 13 in the differential 12. A drive torque is output from the differential 12 to the left and right drive wheels 14. A drive gear 15 attached to the rotor shaft of the second motor 3 meshes with the counter driven gear 9. The drive gear 15 is a gear having a smaller diameter than the counter driven gear 9, and therefore the drive gear 15 and the counter driven gear 9 constitute a reduction mechanism.

  A selectable one-way clutch (hereinafter referred to as SOWC) 17 is provided between the sun gear 5 to which the first motor 2 is connected and the casing 16. In the released state, the SOWC 17 enables relative rotation in either the forward or reverse direction and does not transmit torque. In the engaged state, the relative rotation of only one of the forward and reverse directions is restricted (or prevented). The clutch is configured to transmit the torque in the direction and to allow the relative rotation in the opposite direction and not transmit the torque. Here, the forward rotation is rotation in the same direction as the rotation direction of the engine 1, and the reverse rotation (or negative rotation) is rotation in the direction opposite to the rotation direction of the engine 1. The specific configuration of the SOWC 17 will be described later.

  The first motor 2 and the second motor 3 are connected to a controller unit such as a power storage device or an inverter (not shown), and are electrically connected so that power can be exchanged between them. Further, an electronic control unit (ECU) 18 for controlling these power storage devices, controller unit, SOWC 17 and the like is provided. The electronic control unit 18 is mainly composed of a microcomputer, and detection signals such as the vehicle speed, the accelerator opening, the engine speed and the estimated output torque, the speeds and torques of the motors 2 and 3, and the operating state of the SOWC 17 are received. It is configured to be input as data, perform a calculation based on the data, and output a command signal for controlling each of the motors 2, 3 and SOWC 17.

  FIG. 7 is a schematic diagram showing another example of a power transmission mechanism that can be a subject of the present invention, and an overdrive (O / D) mechanism 19 is additionally provided in the configuration shown in FIG. In this example, the overdrive mechanism 19 is selectively locked by the SOWC 17. The overdrive mechanism 19 is constituted by a double pinion type planetary gear mechanism having a sun gear 20, a carrier 21, and a ring gear 22 as rotating elements. The carrier 6 in the power split mechanism 4 described above is connected to the carrier 21, so that the output torque of the engine 1 is transmitted to these carriers 6, 21. Further, the sun gear 5 in the power split mechanism 4 is connected to the sun gear 20, so that the torque of the first motor 2 is transmitted to the sun gears 5 and 20. Further, the SOWC 17 described above is arranged between the ring gear 22 and the casing 16, and the overdrive state is set by restricting (blocking) the rotation of the ring gear 22 in a predetermined direction (rotation in the positive direction) by the SOWC 17. ing. Therefore, the single pinion type planetary gear mechanism that constitutes the power split mechanism 4 and the double pinion type planetary gear mechanism that constitutes the overdrive mechanism 19 are obtained by connecting the respective rotating elements as described above. This constitutes a so-called four-element compound planetary gear mechanism. Since the other configuration is the same as the configuration shown in FIG. 6, the same reference numerals as those in FIG.

  Here, the configuration of the SOWC 17 will be described. In the power transmission mechanism targeted by the present invention, the SOWC described in Patent Document 1 described above, the SOWC described in US Patent Application Publication No. 2010/0252384, and the like can be employed. A SOWC 17 configured as schematically shown in FIG. 9 can be employed. 8 and 9 show the engagement mechanism 23 in the SOWC 17, and the first clutch plate 24 is formed in a disc shape as a whole, and the disc shape is opposed to the first clutch plate 24. A second clutch plate 25 is arranged. One of the clutch plates 24 and 25 corresponds to the first member in the present invention, and the other clutch plate corresponds to the second member in the present invention. The plates 24 and 25 are held so as to be relatively rotatable. For example, one clutch plate 24 (25) is attached to the casing 16 described above, and the other clutch plate 25 (24) is connected to the sun gear 5 shown in FIG. 6 or to the ring gear 22 shown in FIG.

  A concave portion that is long in the rotational direction is formed at a position shifted radially outward from the center of rotation on the front surface of the first clutch plate 24, that is, a predetermined portion on the outer peripheral side, and this concave portion is a pocket 26. In addition, a notch 27 which is a concave portion having substantially the same shape as the pocket 26 is formed at the same radial position as the pocket 26 on the surface of the second clutch plate 25 facing the first clutch plate 24. The pocket 26 accommodates a plate-like engagement piece (hereinafter referred to as a strut) 28 having a cross-sectional shape substantially equal to the shape of the pocket 26. The strut 28 corresponds to an engaging member in the present invention, and the strut 28 swings around a support pin 29 provided in the center of the length direction thereof in the radial direction of the first clutch plate 24. As shown in FIG. The depth of the pocket 26 varies with the support pin 29 as a boundary, and the upper half of the pocket 26 in FIG. 8 is as deep as the thickness of the strut 28 or slightly deeper than that. The lower half of FIG. 8 opposite to this is deeper than the thickness of the strut 28 and is configured so that the strut 28 can swing around the support pin 29.

  In the shallow portion of the pocket 26, a spring 30 is disposed that applies an elastic force in a direction in which one end of the strut 28 is pushed out of the pocket 26. Further, an actuator 31 that presses the other end side of the strut 28 in the direction of pushing out from the pocket 26 is disposed in a deep portion of the pocket 26. The actuator 31 only needs to be able to apply a pressing force to the other end of the strut 28, and a hydraulic actuator such as a hydraulic piston or an electromagnetic actuator such as a solenoid that generates thrust by electromagnetic force can be employed. . Therefore, in a state where the actuator 31 does not press the other end portion of the strut 28, the strut 28 has one end portion pressed by the spring 30 and protrudes from the pocket 26, whereas the actuator 31 is opposed to the other end portion of the strut 28. In the state in which the strut 28 is pressed, the strut 28 rotates around the support pin 29 in the direction in which the spring 30 is compressed, and the entire strut 28 is configured to be accommodated in the pocket 26. In order to relieve the pressing force by the actuator 31 or to allow the strut 28 to swing while the actuator 31 is pressing the one end of the strut 28, An appropriate elastic member such as a spring may be interposed between the two. Further, in the following description, when the actuator 31 is turned off, the actuator 31 presses the other end of the strut 28 to release the engagement mechanism 23, and when the actuator 31 is turned on, the actuator 31 moves to the other side of the strut 28. An example in which the end mechanism is released and the engagement mechanism 23 is engaged will be described.

  As described above, the notch 27 formed in the second clutch plate 25 is a portion where one end portion of the strut 28 protruding from the pocket 26 is inserted and engaged. Accordingly, the engaging mechanism 23 is configured such that the upward torque in FIG. 8 acts on the first clutch plate 24 with one end of the strut 28 protruding toward the second clutch plate 25 or the second clutch plate 25. When a downward torque in FIG. 8 is applied, the strut 28 is engaged between the pocket 26 and the notch 27 to connect the clutch plates 24 and 25 so as to be integrated in the rotational direction. That is, the relative rotation of the first clutch plate 24 relative to the second clutch plate 25 in the upward direction in FIG. 8, in other words, the relative rotation of the second clutch plate 25 relative to the first clutch plate 24 in the downward direction in FIG. (Differential rotation) is regulated. This restricted rotation direction is the normal rotation direction in the power transmission mechanism shown in FIGS. 6 and 7 described above. The state where the differential rotation in the positive rotation direction of the sun gear 5 or the ring gear 22 is restricted (or prevented) in this way is the engagement state of the engagement mechanism 23 or the SOWC 17. If torque in the reverse rotation direction (negative rotation direction) acts on one of the clutch plates 24 and 25 in this state, that is, the downward torque in FIG. 8 acts on the first clutch plate 24 or the second clutch plate 25. When an upward torque in FIG. 8 is applied, the surface of the strut 28 is pushed by the edge portion of the open end of the notch 27 in the second clutch plate 25, and the strut 28 resists the elastic force of the spring 30 in the pocket 26. Can be pushed in. That is, the engagement by the struts 28 is released, and the clutch plates 24 and 25 can rotate relative to each other.

  When the actuator 31 presses the other end portion of the strut 28, the strut 28 compresses the spring 30 and rotates in the direction in which one end portion enters the pocket 26, so that the strut 28 fits inside the pocket 26. . Accordingly, since there is no member connecting the clutch plates 24 and 25, the clutch plates 24 and 25 can be rotated in both forward and reverse directions. This state is the released state of the engagement mechanism 23 or the SOWC 17.

  As described above, the engagement state and the release state are switched by the operation of the actuator 31, and therefore the actuator 31 corresponds to the switching operation mechanism in the present invention, and the operation state or operation amount of the actuator 31 is detected. Thus, it is possible to determine the engaged state and the released state based on the detection result. A stroke sensor 32 for performing the detection is provided. The stroke sensor 32 may be a conventionally known appropriate sensor, for example, a sensor of a type that detects a stroke by an electrostatic capacity or an electric resistance that changes in accordance with an operation amount of the actuator 31 or optically detects a stroke. It may be a sensor of the type to do. Further, instead of detecting the stroke, a so-called ON / OFF sensor that outputs signals at the forward end and the backward end of the actuator 31 may be used.

  FIG. 10 shows another example of the SOWC 17, and the SOWC 17 shown here is a SOWC of a type provided with a selector plate as a switching operation mechanism in the present invention. Explaining the configuration, the pocket plate 40 and the notch plate 41 are arranged so as to face each other on the same axis and be relatively rotatable. The pocket plate 40 and the notch plate 41 correspond to the first member or the second member in the present invention. The pocket plate 40 has a pocket 43 for accommodating the strut 42 corresponding to the engaging member in the present invention. A plurality of lines are formed side by side in the circumferential direction at locations deviating from the rotational center of 40 in the radial direction. The strut 42 is a rectangular plate-like member similar to the strut 28 described above. The strut 42 swings (becomes up and down) around one end, and is placed in the pocket 43, and the other end is It is configured to operate in a state of protruding to the notch plate 41 side. A spring 44 is disposed on the back side (lower side in FIG. 10) of the strut 42, and the other end of the strut 42 is pushed out toward the notch plate 41 by the elastic force of the spring 44. Therefore, the strut 42 is configured to be pushed back toward the inside of the pocket 43 when pushed by a strong force that resists the elastic force of the spring 44.

  A notch 45 corresponding to the strut 42 is formed on the surface of the notch plate 41 facing the pocket plate 40. The notches 45 are rectangular recesses into which one end of the strut 42 is inserted to engage the strut 42, and a plurality of the notches 45 are formed side by side in a circumferential direction at a position facing the strut 42. Therefore, when a torque in a direction in which one end of the strut 42 abuts against the inner wall surface of the notch 45 acts between the pocket plate 40 and the notch plate 41, the pocket plate 40 and the notch plate 41 are connected by the strut 42. Their relative rotation (differential rotation) is restricted. That is, the clutch is engaged. When torque acts in the opposite direction, the upper surface of the strut 42 is pushed by the open end of the notch plate 41 or the notch 45, so that the strut 42 is pushed back toward the pocket plate 40, and the strut 42 comes out of the notch 45. That is, since the connection between the pocket plate 40 and the notch plate 41 via the strut 42 is released, the relative rotation (negative differential rotation) of the pocket plate 40 and the notch plate 41 becomes possible. Eventually, the clutch functions as a one-way clutch.

  A selector plate 46 is disposed between the pocket plate 40 and the notch plate 41 so as to be rotatable relative to the pocket plate 40 and the notch plate 41. The selector plate 46 is a member made of, for example, an annular thin plate, and a plurality of openings 47 are formed at predetermined intervals in the circumferential direction at locations corresponding to the struts 42 and the notches 45. The opening 47 is formed in a shape that allows the strut 42 to pass through and protrude toward the notch plate 41.

  The selector plate 46 is configured to move between a state in which the opening 47 coincides with the position of the strut 42 and a state in which the opening 47 is displaced from the position of the strut 42 and the strut 42 is pushed into the pocket 43. In addition, an actuator 48 for moving the selector plate 46 to such two states is provided. The actuator 48 includes a hydraulic cylinder, an electromagnetic solenoid, a direct acting motor, and the like. Further, a sensor 49 for detecting the stroke or operating position of the actuator 48 or selector plate 46 is provided. The sensor 49 may be the same as the stroke sensor 32 described above.

  In the SOWC 17 according to the present invention, when the first member and the second member described above rotate relative to each other in the negative direction, the engaging member is engaged with the other member side of these members. Even if it protrudes, the effect | action pushed back by the said other member, ie, a ratchet effect, arises. Such a ratchet action serves as a one-way clutch. The SOWC 17 according to the present invention can be configured such that a ratchet action (a skipping state in the present invention) occurs even when the first member and the second member are relatively rotated in a so-called positive direction. An example of a ratchet structure for this purpose is shown in FIG.

  The example shown here is an example of the SOWC 17 of the type having the selector plate 46 described above, and the upper surface (the surface facing the notch plate 41 side) at one end of the strut 42 is gradually thinner at the one end. It is formed in the circular arc surface 42a so that it may become. In addition, the inner surface of the opening end of the notch 45 where the one end of the strut 42 engages is the opening end of the hook, in other words, when the pocket plate 40 and the notch plate 41 are rotated relative to each other in the forward direction. A corner portion facing 42a is chamfered into a convex curved surface to form a convex arc surface 45a. Therefore, when the relative rotational speed between the pocket plate 40 and the notch plate 41 in the forward rotation direction is larger than a predetermined value, one end portion (tip portion) of the strut 42 does not enter the notch 45 and the arc surface 42a described above. And the convex arc surface 45a collide, and the strut 42 is rebounded. That is, a ratchet action occurs, and the SOWC 17 is maintained in a released state.

  The control device according to the present invention determines the failure of the sensors 32 and 49 when the detection signals of the sensors 32 and 49 indicate the engaged state of the SOWC 17 in a state where the SOWC 17 is controlled to the released state. Therefore, the control described below is performed. FIG. 1 is a flowchart for explaining the control example, and the routine shown here is repeatedly executed every predetermined short time when the SOWC 17 is controlled to be in the released state. First, it is determined whether or not it has been detected that the actuators (Act.) 31, 48 have stroked to operate the struts 28, 42 into the engaged state (step S1). This can be performed based on signals output from the sensors 32 and 49 described above.

  If the determination in step S1 is negative, the SOWC 17 maintains the released state, and thus returns without performing any control. On the other hand, if a positive determination is made in step S1, some abnormality has occurred, and the control mode is shifted to the sensor abnormality confirmation mode (step S2). Specifically, this control mode is control for changing the differential rotation speed in the SOWC 17, and a flag for indicating or instructing the start of the control is turned ON.

  Next, it is determined whether or not the differential rotational speed in the SOWC 17 is greater than “0” (step S3). Here, the differential rotational speed being larger than “0” means that the differential rotational direction in the SOWC 17 is a positive rotational direction in which torque is transmitted through the struts 28 and 42 described above. Therefore, if the determination in step S3 is affirmative, it is determined in step S1 that the actuators 31 and 48 have moved in a direction to bring the SOWC 17 into the engaged state. There is a possibility that torque is transmitted in an engaged state. In the power transmission mechanism having the configuration shown in FIG. 6, the rotation of the sun gear 5 may be stopped, and in the power transmission mechanism having the configuration shown in FIG. 7, the rotation of the ring gear 22 may be stopped. Therefore, if a positive determination is made in step S3, control for confirming whether or not such a change in the rotational speed occurs is executed. Specifically, the differential rotation speed is gradually changed so as to be a negative rotation (step S4). When the rotational speed of the differential rotation in the positive rotation direction is gradually decreased and the control is continued, the rotational speed of the differential rotation in the negative rotation direction is gradually increased.

  In the above-described SOWC 17 that is the subject of the present invention, if a differential rotation in the positive rotation direction occurs and the rotation speed is equal to or greater than a predetermined value, a ratchet action occurs and the SOWC 17 does not enter an engaged state. In the power transmission mechanism shown in FIGS. 6 and 7, the rotation of the sun gear 5 and the ring gear 22 is not immediately stopped. The ratchet action in the forward rotation direction is surely generated if the differential rotational speed is equal to or higher than the first reference rotational speed determined by design, and the differential rotational speed is determined by design with a value smaller than the first reference rotational speed. If the rotational speed is less than the second reference rotational speed, the ratchet action does not occur and the SOWC 17 is engaged, and the rotation of the sun gear 5 and the ring gear 22 is stopped. If the differential rotation speed is within the range determined by the first reference rotation speed and the second reference rotation speed, a so-called unstable state in which the ratchet action occurs or does not occur.

  Therefore, when the differential rotational speed is gradually reduced by the control in step S4, if the SOWC 17 is operated in the engaged state, the ratchet action described above does not occur at any time, and the SOWC 17 transmits torque. A substantial engagement state. On the other hand, if the sensors 32 and 49 only output signals and the SOWC 17 itself is not operated to switch to the engaged state, the SOWC 17 transmits torque even if the differential rotational speed is reduced. Must not. Such a change in the differential rotational speed is determined in step S5. That is, it is determined whether or not the differential rotation speed has suddenly changed. The change in the differential rotational speed is the change in the rotational speed of the sun gear 5 of the planetary gear mechanism constituting the power split mechanism 4 or the rotational speed of the ring gear 22 of the planetary gear mechanism constituting the overdrive mechanism 19. Since it appears as a change, the number of revolutions of the sun gear 5 or the ring gear 22 may be detected to make the determination in step S5. Alternatively, since the engine speed also changes, the determination in step S5 may be made based on the engine speed. The “sudden change” is a rapid change in the rotational speed that exceeds the speed of change due to the control of the differential rotational speed in step S4. A determination reference value is set in advance, and the detected rotational speed change is determined. By comparing the speed with the determination reference value, it is possible to determine whether or not it is “sudden change”. The determination reference value may be the speed of change in the rotational speed by controlling the differential rotational speed in step S4.

  If the determination in step S5 is affirmative, it is determined that the sensors 32 and 49 are normal (step S6), and the process returns. The sudden change in the differential rotation speed is caused by the engagement of the leading ends of the struts 28 and 42 that have not been engaged by the ratchet action into the notches 27 and 45 as the differential rotation speed decreases. The SOWC 17 is operated by the actuators 31 and 48 so as to be in the engaged state. Therefore, since the output signals of the sensors 32 and 49 coincide with the operation states of the actuators 31 and 48 or the SOWC 17, it is determined that the sensors 32 and 49 are normal.

  On the other hand, the state determined negative in step S5 is that the differential rotation direction at SOWC 17 is the positive rotation direction, and SOWC 17 is engaged even though a signal for switching SOWC 17 to the engaged state is output. It is a state that does not become a joint state. Possible causes are that the detection signal is output in error and a mechanical failure in the SOWC 17. Therefore, first, the differential rotational speed changed to the differential rotational speed in the negative rotational direction is gradually increased to the rotational speed in the positive rotational direction (step S7). And the change of the difference rotation speed accompanying it is judged (step S8). That is, it is determined whether or not the differential rotational speed has suddenly changed, or whether or not the differential rotational speed in the forward rotational direction does not increase. If the determination in step S8 is affirmative, it is determined that the sensors 32 and 49 are normal (step S9), and the process returns. On the contrary, if a negative determination is made in step S8, it is determined that an abnormality has occurred in the sensors 32 and 49 (step S10), and the process returns.

  That is, when the differential rotational speed suddenly changes when the differential rotational speed is increased in the positive rotational direction, or when the differential rotational speed does not increase in the positive rotational direction, the SOWC 17 is engaged, for example, the sun gear 5 or In this state, the rotation of the ring gear 22 is stopped. That is, since the SOWC 17 is brought into the engaged state, the output signals of the sensors 32 and 49 coincide with the operation states of the actuators 31 and 48 or the SOWC 17 and the sensors 32 and 49 are normal. (Step S9) is established. On the other hand, if the differential rotational speed increases in the forward rotational direction, the SOWC 17 is in the released state although the output signals of the sensors 32 and 49 indicate the engaged state of the SOWC 17. It will be. That is, the output signals of the sensors 32 and 49 do not match the operation states of the actuators 31 and 48 or the SOWC 17, and the determination that the sensors 32 and 49 are abnormal is established (step S10). .

  The control for changing the above-described differential rotational speed can be performed by the first motor 2, and this will be described with reference to a collinear diagram of the planetary gear mechanism that constitutes the power split mechanism 4 and the overdrive mechanism 19 described above. It is as follows. 2 (a) and 3 (a) are examples in which the differential rotational speed is gradually decreased from the rotational speed in the positive rotational direction toward the rotational speed in the negative rotational direction. FIG. 2A is a collinear diagram for the power split mechanism shown in FIG. 6 described above, and the line indicated as “normal travel” indicates when the sensors 32 and 49 output a so-called engagement signal. Shows the state. In the configuration shown in FIG. 6, since the first motor 2 is connected to the SOWC 17, the differential rotational speed of the SOWC 17 in the positive rotational direction gradually decreases by gradually decreasing the rotational speed. If the sensors 32 and 49 are normal and the SOWC 17 is operated in the engaged state, the ratchet action of the SOWC 17 does not occur in the process of reducing the differential rotational speed, and the SOWC 17 is switched to the engaged state. Immediately at the time, the rotational speeds of the sun gear 5 and the first motor 2 connected thereto suddenly change to “0”. On the other hand, when the SOWC 17 is not switched to the engaged state, the SOWC 17 is not engaged even if the differential rotational speed is reduced in the negative rotation direction. Therefore, the rotation of the first motor 2 and the sun gear 5 integrated therewith is not performed. The number, that is, the differential rotational speed at SOWC 17 becomes the rotational speed in the negative rotational direction. This is indicated by the line “sensor abnormality confirmation mode” in FIG.

  Similarly, FIG. 3A is an example of the power transmission mechanism shown in FIG. 7, and the rotational speeds of the sun gears 5 and 20 are gradually increased by the first motor 2 from the state indicated by the line “normal travel”. Reduce. Accordingly, the rotational speed of the ring gear 22 connected to the SOWC 17 (that is, the differential rotational speed of the SOWC 17) gradually decreases in the negative rotational direction. If there is no abnormality in the sensors 32 and 49 and the SOWC 17 is operated in the engaged state, the SOWC 17 is engaged in the process and the rotation speed of the ring gear 22 immediately becomes “0”. This state is indicated by a line “sensor abnormality confirmation mode” in FIG. On the other hand, when the SOWC 17 is not operated in the engaged state, the SOWC 17 is not engaged even if the differential rotational speed is changed as described above, so the rotational speeds of the sun gears 5 and 20 and the ring gear 22 are The number of rotations in the negative rotation direction. The differential rotational speed of the SOWC 17 is also the rotational speed in the negative rotational direction.

  2B and 3B are examples in which the differential rotation speed is gradually increased from the rotation speed in the negative rotation direction toward the rotation speed in the positive rotation direction. FIG. 2B is a collinear diagram for the power split mechanism shown in FIG. 6 described above, and the line indicated as “normal travel” indicates when the sensors 32 and 49 output a so-called engagement signal. Shows the state. In the configuration shown in FIG. 6, since the first motor 2 is connected to the SOWC 17, the differential rotational speed of the SOWC 17 in the negative rotational direction gradually decreases and becomes “0” by gradually increasing the rotational speed. The rotational speed in the positive rotation direction gradually increases. If the sensors 32 and 49 are normal and the SOWC 17 is operated in the engaged state, the SOWC 17 is engaged by the struts 28 and 42 in the process of increasing the differential rotational speed in this way. Immediately after that, the rotational speed of the sun gear 5 and the first motor 2 connected thereto suddenly changes to “0”. Alternatively, the differential rotation speed does not increase to the rotation speed in the positive rotation direction. On the other hand, when the SOWC 17 is not switched to the engaged state, the SOWC 17 is not engaged even if the differential rotational speed is increased in the forward rotation direction. Therefore, the rotation of the first motor 2 and the sun gear 5 integrated therewith is not performed. The number, that is, the differential rotational speed at SOWC 17 is the rotational speed in the forward rotational direction. This is shown by the line “sensor abnormality confirmation mode” in FIG.

  Similarly, FIG. 3B is an example of the power transmission mechanism shown in FIG. 7, and the rotational speeds of the sun gears 5 and 20 are gradually increased by the first motor 2 from the state indicated by the line “normal travel”. Increase. Accordingly, the rotational speed of the ring gear 22 connected to the SOWC 17 (that is, the differential rotational speed of the SOWC 17) gradually increases in the positive rotational direction. If there is no abnormality in the sensors 32 and 49 and the SOWC 17 is operated in the engaged state, the SOWC 17 is engaged in the process and the rotation speed of the ring gear 22 immediately becomes “0”. Alternatively, the ring gear 22 does not rotate in the forward rotation direction. On the other hand, when the SOWC 17 is not operated in the engaged state, the SOWC 17 is not engaged even if the differential rotational speed is changed as described above, so the rotational speeds of the sun gears 5 and 20 and the ring gear 22 are The number of rotations in the forward rotation direction. The differential rotational speed of the SOWC 17 is also the rotational speed in the forward rotational direction. This state is indicated by a line “sensor abnormality confirmation mode” in FIG.

  An example of a change in the differential rotation speed when the above control is performed is shown in FIG. When the stroke signal of the unintended actuators 31 and 48 is detected at the time t1 when the differential rotation speed is the rotation speed in the forward rotation direction with the SOWC 17 controlled to the released state, the sensor 32 is detected at the time t2 immediately after that. , 49 are started. As a result, the differential rotation speed is gradually reduced toward the rotation speed in the negative rotation direction. If the SOWC 17 is operated in the engaged state according to the signals of the sensors 32 and 49, the SOWC 17 is switched to the engaged state in the process, and the differential rotational speed immediately changes rapidly to “0”.

  When the SOWC 17 is not operating in the engaged state, the differential rotation speed gradually decreases as controlled by the first motor 2, and finally becomes a differential rotation in the negative rotation direction. The duration of the differential rotation in the negative rotation direction is preferably a time for which the notches 27 and 45 facing the struts 28 and 42 pass through the positions of the struts 28 and 42, for example. Thereafter, the differential rotation speed is gradually increased toward the rotation speed in the positive rotation direction. If the SOWC 17 is operated in the engaged state according to the signals of the sensors 32 and 49, the differential rotation speed does not increase to “0” or more by switching to the engaged state in the process.

  If the SOWC 17 does not engage even when the differential rotational speed becomes “0”, the differential rotational speed is increased to a predetermined rotational speed in the forward rotational direction and maintained. This predetermined rotational speed is a rotational speed smaller than the ratchet minimum rotational speed lower limit. Here, the ratchet minimum rotation speed will be described. Due to the ratchet structure described above, the struts 28 and 42 are bounced back to the notches 27 and 45 when the rotation speed in the forward rotation direction is high to some extent, so that the struts 28 and 42 are not engaged. . In other words, the ratchet action is surely generated and the engaged state is not reached at a predetermined rotation speed or higher according to the ratchet structure described above. This “predetermined rotational speed” is the ratchet minimum rotational speed upper limit, and is the first reference rotational speed described above. Moreover, if it is less than other predetermined rotation speed, a ratchet effect | action does not arise and it engages reliably. This “other predetermined rotational speed” is the second reference rotational speed described above. At the rotation speeds between these respective reference rotation speeds, a ratchet action does not occur or does not occur, and it is a so-called unstable region where the engagement state is not reached or the engagement state is not reached. The differential rotational speed increased from the negative rotational direction is lower than the second reference rotational speed. Then, when the differential rotational speed is maintained at the rotational speed in the positive rotational direction, the determination that the sensors 32 and 49 are normal is established by suddenly changing the differential rotational speed to “0” (at time t3). ).

  Another control example executed by the control device according to the present invention is shown in FIG. The example shown here is an example in which an abnormality (failure) of the sensors 32 and 49 is determined while the vehicle is stopped. That is, first, it is determined whether or not an unintended stroke (operation in the direction in which the SOWC 17 is engaged) of the actuators 31 and 48 is detected (step S11). If the determination is affirmative, the sensor abnormality confirmation mode is set. Transition is made (step S12). These control steps are the same as steps S1 and 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.

  In the sensor abnormality confirmation mode, first, it is determined whether or not the vehicle is stopped (step S13). This determination may be a determination as to whether or not the vehicle speed is a predetermined value or less. If a negative determination is made in step S13, the process returns without performing any particular control. On the other hand, when a positive determination is made in step S13, control for maintaining the stopped state is executed (step S14). Specifically, the torque of the second motor 3 described above is output so that the brake is turned on or the vehicle is stopped, or the parking mechanism is operated in the locked state. Next, torque in the forward rotation direction is applied by the first motor 2 (step S15). In the example shown in FIG. 6 described above, torque in the forward rotation direction is applied to the sun gear 5, and in the example shown in FIG. 7, torque in the forward rotation direction is applied to the ring gear 22. In that case, torque acts on the ring gear 7 that is an output member in the power split mechanism 4, but since the control for maintaining the stopped state is executed in step S <b> 14, it is particularly generated whether the vehicle is moving or not. Absent.

  In this manner, it is determined whether or not the engine speed has increased with the torque applied (step S16). As known from the collinear charts shown in FIG. 2 and FIG. 3 described above, when the rotation of the ring gear 7 is stopped and torque in the forward rotation direction is applied to the sun gear 5 or the ring gear 22, the engine is not engaged if the SOWC 17 is not engaged. If 1 rotates together with the carriers 6 and 21 in the forward rotation direction and the SOWC 17 is engaged on the contrary, the carrier 6 and 21 will not rotate although torque in the forward rotation direction is applied. Therefore, if the determination in step S16 is affirmative, that is, if the engine speed increases, the SOWC 17 is released. Since this is a state opposite to the state represented by the signals output from the sensors 32 and 49, it is determined that the sensors 32 and 49 are abnormal (step S17). On the other hand, if a negative determination is made in step S16, the state in which the engine speed does not increase matches the state represented by the signals output from the sensors 32 and 49. It is determined that the sensors 32 and 49 are normal (step S18). As described above, according to the control example shown in FIG. 5, it is possible to determine abnormality without causing a change in the behavior of the vehicle.

  DESCRIPTION OF SYMBOLS 1 ... Engine (Eng), 2 ... 1st motor (MG1), 3 ... 2nd motor (MG2), 4 ... Power split mechanism, 5 ... Sun gear, 6 ... Carrier, 7 ... Ring gear, 8 ... Output gear, 9 ... Counter driven gear, 16 ... casing, 17 ... selectable one-way clutch (SOWC), 18 ... electronic control unit (ECU), 19 ... overdrive (O / D) mechanism, 20 ... sun gear, 21 ... carrier, 22 ... ring gear, 23 ... Engaging mechanism, 24 ... first clutch plate, 25 ... second clutch plate, 26 ... pocket, 27 ... notch, 28 ... engaging piece (strut), 29 ... support pin, 30 ... spring, 31 ... actuator, 32 ... Stroke sensor 40 ... Pocket plate 41 ... Notch plate 42 ... Strut 4 3 ... Pocket, 44 ... Spring, 45 ... Notch, 46 ... Selector plate, 47 ... Opening, 48 ... Actuator, 49 ... Sensor, 42a ... Arc surface, 45a ... Convex arc surface.

Claims (1)

The first member and the second member are provided, and the first member and the second member are not engaged with each other in a state where the first member and the second member are rotating relative to each other in the positive rotation direction at a rotational speed equal to or higher than a predetermined differential rotational speed. In the forward rotation state less than the rotational speed, the engagement state is switched to the engagement state and torque is transmitted between the first member and the second member, and the torque is not transmitted in the negative rotation direction opposite to the positive rotation direction. A selectable one-way clutch that is selectively set to a disengaged state that does not transmit torque in either the positive rotation direction or the negative rotation direction, and the selectable one-way clutch is switched between the engaged state and the disengaged state. A failure determination device for a power transmission mechanism for a vehicle, comprising: a switching operation mechanism to be operated; and a sensor that detects an operation of the selectable one-way clutch by the switching operation mechanism. ,
When the sensor outputs a signal indicating that the selectable one-way clutch is engaged during execution of the control for setting the selectable one-way clutch to the released state, the first member and the second member Executing control for changing the differential rotational speed, and the differential rotational speed by changing or not changing the state of disengagement of the selectable one-way clutch in association with executing the control for changing the differential rotational speed A failure determination device for a vehicle power transmission mechanism, wherein the failure determination of the sensor is performed in accordance with a change state of the vehicle.

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