Transmission control device, transmission control method, and program

Abstract

A release-side engagement element is smoothly shifted from a one-way clutch state to a release state. A transmission control device is used in a transmission having a first engagement element, a second engagement element, and a third engagement element. A control device for a transmission engages a second engagement element after transitioning the first engagement element from a one-way clutch state to a released state by driving an actuator of the first engagement element in a state in which the third engagement element is slid.

Description

Technical Field

[0001] The present invention relates to a transmission control device, a transmission control method and a program. Background Art

[0002] Patent document 1 discloses a vehicle drive device in which a rotating electric machine and a transmission are arranged on a first shaft, and a differential gear device is arranged on a second shaft. The transmission gear mechanism includes a first planetary gear mechanism having a first one-way clutch and a second planetary gear mechanism having a second one-way clutch. The first one-way clutch and the second one-way clutch are both selectable one-way clutches, and the selectable one-way clutch is configured to be switchable between a one-way restriction state that restricts one-way rotation, a two-way restriction state that restricts two-way rotation, and a release state that allows two-way rotation. Prior art

[0003] Patent Literature

[0004] Patent Document 1: (Japanese) Patent Publication No. 2020-175707 Summary of the invention

[0005] Technical problem to be solved by the invention

[0006] In a transmission having an engagement element engaged in a one-way clutch state (one-way restricted state), when the engagement element is switched during speed change, the engagement element engaged in the one-way clutch state can become the release-side engagement element. However, in this case, the engagement connection is performed by the release-side engagement element. Therefore, when the torque acts on the release-side engagement element, the force required for release becomes larger accordingly. As a result, it is possible that the release cannot be performed smoothly due to the torque acting on the release-side engagement element.

[0007] The present invention has been made in view of such a problem, and an object of the present invention is to smoothly transition a release-side engagement element from a one-way clutch state to a released state.

[0008] Technical solutions for solving technical problems

[0009] A transmission control device according to one aspect of the present invention is used in a transmission having a first engagement element, a second engagement element, and a third engagement element. The transmission control device drives an actuator of the first engagement element while the third engagement element is in a slipping state, and after the first engagement element is changed from a one-way clutch state to a released state, the second engagement element is engaged.

[0010] According to another aspect of the present invention, a control method of a transmission corresponding to the control device of the transmission is provided. In addition, according to another aspect of the present invention, a program corresponding to the control device of the transmission is provided.

[0011] Effects of the Invention

[0012] According to these aspects, when the first engaging element as the release side engaging element is changed from the one-way clutch state to the released state, the torque sharing of the first engaging element is reduced by increasing the torque sharing of the third engaging element. As a result, the reaction force applied to the engaging portion of the first engaging element can be reduced, so the first engaging element can be released smoothly. It should be noted that, for example, if the torque sharing of the third engaging element is increased all at once to make it fully connected, the impact becomes larger. Therefore, it is preferred to set the sliding state in which the shared torque to be borne is smaller than that of the fully engaged state. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the unit.

[0014] Figure 2 This is a schematic diagram of the unit.

[0015] Figure 3 It is a diagram showing a connection table of a speed change mechanism.

[0016] Figure 4A This is the first diagram for explaining the switching mechanism.

[0017] Figure 4B This is the second diagram for explaining the switching mechanism.

[0018] Figure 4C This is the third diagram for explaining the switching mechanism.

[0019] Figure 5 This is a diagram showing an example of control according to the embodiment as a flowchart.

[0020] Figure 6 This is a diagram showing an example of a timing chart of the embodiment. DETAILED DESCRIPTION

[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0022] Figure 1 1 is a schematic structural diagram of the unit 100 . Figure 2 1 is a schematic diagram of a unit 100. Regarding the terminology of the unit, the unit can also be referred to as, for example, a motor unit (a unit having at least a motor) or a power transmission device (a device having at least a power transmission mechanism). The motor is a rotating electrical machine having a motor function and / or a generator function (at least one of the motor function and the generator function). The power transmission mechanism is, for example, a gear mechanism and / or a differential gear mechanism. The device (unit) having a motor and a power transmission mechanism is included in the concepts of both the motor unit and the power transmission device.

[0023] like Figure 1 As shown, the unit 100 includes a housing 10 and a speed change mechanism 20. The unit 100 is mounted on a vehicle, which is an electric vehicle. Power from the MG 40 is input to the unit 100. The MG 40 is a rotating electrical machine that functions as a motor generator, and the unit 100 can also be understood as a structure that also includes the MG 40.

[0024] The housing 10 accommodates the speed change mechanism 20. The speed change mechanism 20 includes a housing 21, a rotating shaft 22, a first planetary gear mechanism PGM1, a second planetary gear mechanism PGM2, a first brake B1, a second brake B2, and a clutch CL. The housing 21 has a cylindrical shape and is fixed to the inner circumference of the housing 10. The first planetary gear mechanism PGM1 is provided in the housing 21 via the first brake B1, and the second planetary gear mechanism PGM2 is provided via the second brake B2. The rotating shaft 22 is connected to the MG40 and rotated by the power from the MG40. The extending direction of the rotating shaft 22 is equivalent to the axial direction of the unit 100, which refers to the axial direction of the rotating shaft of the components (such as the motor, the gear mechanism, and the differential gear mechanism) constituting the unit.

[0025] The first planetary gear mechanism PGM1 includes a first sun gear S1, a first planetary carrier C1, a first ring gear R1, and a first pinion P1. The first sun gear S1 is coaxially fixed to the rotating shaft 22. The first planetary carrier C1 rotatably supports the first pinion P1. The first pinion P1 meshes with both the first sun gear S1 and the first ring gear R1. The same applies to the second planetary gear mechanism PGM2 including a second sun gear S2, a second planetary carrier C2, a second ring gear R2, and a second pinion P2.

[0026] The second planetary gear mechanism PGM2 is arranged in an axial direction with the first planetary gear mechanism PGM1. Therefore, the first planetary gear mechanism PGM1 has a portion that overlaps with the second planetary gear mechanism PGM2 when viewed in the axial direction. The so-called overlapping in a specified direction including radial observation and axial observation refers to overlapping in a specified direction, which means that a plurality of elements are arranged in the specified direction. Therefore, the situation in which a plurality of elements are arranged in a specified direction in the accompanying drawings can be regarded as an article in the specification that explains the situation in which a plurality of elements overlap when viewed in a specified direction.

[0027] The second planetary gear mechanism PGM2 is arranged on a side away from the MG40 relative to the first planetary gear mechanism PGM1. The second planetary carrier C2 is connected to the first ring gear R1 by being formed integrally with the first ring gear R1. The second planetary carrier C2 constitutes an output element of the second planetary gear mechanism PGM2. In contrast, the first planetary carrier C1 constitutes an output element of the first planetary gear mechanism PGM1, and constitutes an output element of the first planetary gear mechanism PGM1 and the second planetary gear mechanism PGM2 as a whole, thereby constituting an output element of the entire speed change mechanism 20.

[0028] The first brake B1 is provided on the outer periphery of the first ring gear R1 and is connected to the first planetary gear mechanism PGM1. In addition, the second brake B2 is provided on the outer periphery of the second ring gear R2 and is connected to the second planetary gear mechanism PGM2. Therefore, the first brake B1 has a portion overlapping with the first planetary gear mechanism PGM1 when viewed in the radial direction, and the second brake B2 has a portion overlapping with the second planetary gear mechanism PGM2 when viewed in the radial direction.

[0029] The first brake B1 and the second brake B2 are both meshing engagement elements and have a meshing connection structure. When the first brake B1 is connected, the first ring gear R1 is fixed to the housing 21 together with the second planetary carrier C2. As a result, the first ring gear R1 is fixed to the housing 10 together with the second planetary carrier C2. When the second brake B2 is connected, the second ring gear R2 is fixed to the housing 21. As a result, the second ring gear R2 is fixed to the housing 10. The first brake B1 is equivalent to the first engagement element, and the second brake B2 is equivalent to the second engagement element.

[0030] The clutch CL is arranged axially side by side with the second planetary gear mechanism PGM2 from the side away from the MG 40. The clutch CL is provided relative to the rotating shaft 22 and the second planetary carrier C2 to connect and disconnect them. The clutch CL is a friction engagement element and is a multi-plate clutch. The clutch CL is, for example, an electric clutch and includes a hub 23, a roller 24, a plurality of drive plates 25, a plurality of driven plates 26, and a piston 27.

[0031] The hub 23 is coaxially fixed to the rotating shaft 22. The hub 23 has an inner cylindrical portion 23a, an outer cylindrical portion 23b, and a bottom wall portion 23c connecting them, and is coaxially fixed to the rotating shaft 22 through the inner cylindrical portion 23a. The drum 24 has a cylindrical portion 24a and a bottom wall portion 24b, and is coaxially arranged relative to the rotating shaft 22. The drum 24 opens in a direction away from the MG 40. The hub 23 is accommodated in the drum 24, and the outer periphery of the outer cylindrical portion 23b of the hub 23 is opposite to the inner periphery of the cylindrical portion 24a of the drum 24. The drum 24 is fixedly connected to the second planetary carrier C2 through the annular plate-shaped bottom wall portion 24b.

[0032] A plurality of drive plates 25 are provided on the hub 23. The plurality of drive plates 25 have an annular shape and are slidably provided on the outer periphery of the outer cylindrical portion 23b in the axial direction. A plurality of driven plates 26 are provided on the roller 24. The plurality of driven plates 26 have an annular shape and are slidably provided on the inner periphery of the cylindrical portion 24a in the axial direction. The plurality of drive plates 25 and the plurality of driven plates 26 are alternately arranged one by one in the axial direction.

[0033] The piston 27 is disposed in the roller 24. The piston 27 is slidably disposed on the inner periphery of the opening end of the roller 24. The piston 27 is, for example, an electric piston driven by an electric actuator of the clutch CL. Figure 1 right direction) and the engagement release direction ( Figure 1 The plurality of drive plates 25 and the plurality of driven plates 26 are moved in the left direction to engage and disengage the plurality of drive plates 25 and the plurality of driven plates 26.

[0034] When the plurality of drive plates 25 and the plurality of driven plates 26 are pressed in the engagement direction by the piston 27 and are engaged, the clutch CL is in the engaged state. As a result, the rotating shaft 22 is connected to the second planetary carrier C2 via the clutch CL. In addition, if the piston 27 moves from this state to the disengagement direction and the plurality of drive plates 25 and the plurality of driven plates 26 are no longer engaged, the clutch CL is in the disengagement state. As a result, the connection between the rotating shaft 22 and the second planetary carrier C2 via the clutch CL is cut off. In the speed change mechanism 20, the speed change stage is formed as follows according to the connection and release state of the clutch CL, the first brake B1 and the second brake B2.

[0035] Figure 3 2 is a diagram showing a connection table of the speed change mechanism 20. Figure 3 As shown, the speed change mechanism 20 is configured as a three-speed speed change mechanism having three speed stages, namely, 1st, 2nd and 3rd, i.e., 1st speed, 2nd speed and 3rd speed. 1st speed is achieved by engaging the first brake B1 and releasing the second brake B2 and the clutch CL. 2nd speed is achieved by engaging the second brake B2 and releasing the first brake B1 and the clutch CL. 3rd speed is achieved by engaging the clutch CL and releasing the first brake B1 and the second brake B2.

[0036] return Figure 1 The unit 100 further includes a driving device 30. The driving device 30 is a driving device for the first brake B1 and the second brake B2, and includes an actuator 31 and a worm gear 32. Figure 1 In FIG. 1 , the actuator 31 is schematically indicated by a two-dot chain line.

[0037] The actuator 31 is an electric motor and has a worm gear 311. The worm gear 311 constitutes the rotation axis of the actuator 31 and meshes with the worm wheel 32. The worm axis of the worm gear 311 and the central axis of the worm wheel 32 are orthogonal to each other, and the worm wheel 32 is configured to be rotatably driven around the axis of the unit 100 by the power from the actuator 31. Therefore, the worm axis direction of the worm gear 311, that is, the length direction, intersects with the axial direction of the unit 100.

[0038] The worm gear 311 is provided between the first brake B1 and the second brake B2 in the axial direction of the unit 100. Therefore, the actuator 31 has a portion sandwiched between the first brake B1 and the second brake B2. In the actuator 31, the worm gear 311 has such a portion. The worm wheel 32 is provided between the first planetary gear mechanism PGM1 and the second planetary gear mechanism PGM2 in the axial direction of the unit 100.

[0039] The first brake B1 has a first switching mechanism SWM1, and the second brake B2 has a second switching mechanism SWM2. The first switching mechanism SWM1 switches the engagement state of the first brake B1, and the second switching mechanism SWM2 switches the engagement state of the second brake B2.

[0040] FIG. 4A to FIG. 4C is an illustration of the switching mechanism SWM. Figure 4A In FIG. 1 , the first switching mechanism SWM1 is represented in a bidirectional restriction state. Figure 4B In FIG. 1 , the first switching mechanism SWM1 is represented in a one-way restricted state. Figure 4C In FIG. 1 , the first switching mechanism SWM1 is shown in a released state. FIG. 4A to FIG. 4C In the description, the first switching mechanism SWM1 is taken as an example as the switching mechanism SWM, but the second switching mechanism SWM2 is also the same.

[0041] The first switching mechanism SWM1 includes a first fixed side component CB1, a first rotating side component RB1, a first claw CW1, and a first switching part SW1. The first fixed side component CB1 has an annular shape and is fixed to the inner circumference of the housing 21. The first claw CW1 is an engaging portion, and is provided in a portion of the first fixed side component CB1 protruding radially inward. The portion is provided with a plurality of first claws CW1 in the circumferential direction, and two first claws CW1 are provided for each portion as a set of claws. In a set of claws, the first claws CW1 are provided in opposite directions to each other corresponding to the two-way rotation directions.

[0042] The first claw CW1 has a structure in which the radially inner front end portion rotates about the radially outer base end portion as an axis. The first claw CW1 switches between a locked position for locking the rotation of the first ring gear R1 and a free position for being free, and is urged toward the locked position by a spring as an urging member. Figure 4AIn the state shown, the first claws CW1 are urged toward the locking position by springs, respectively.

[0043] The first rotating side member RB1 is fixed to the outer periphery of the first ring gear R1. The first rotating side member RB1 has an annular shape and has an engaging portion formed of a plurality of convex portions arranged evenly in the circumferential direction on the outer periphery. The first claw CW1 engages with the engaging portion and forms a meshing connection structure together with the engaging portion. The first claw CW1 prevents the first ring gear R1 from rotating in one direction of rotation and allows the first ring gear R1 to rotate in the other direction of rotation.

[0044] For example, the first claw CW1 on the left side of the left and right groups of claws in the figure does not move its front end radially outward to prevent the first gear ring R1 from rotating in the right direction of the figure, but moves its front end radially outward to allow the first gear ring R1 to rotate in the left direction. The first claw CW1 on the right side prevents the first gear ring R1 from rotating in the left direction, but allows the first gear ring R1 to rotate in the right direction. As a result, Figure 4A In the bidirectional restriction state shown, the first ring gear R1 is restricted from rotating in both the left and right directions. Therefore, the first brake B1 is in the engaged state with respect to the bidirectional rotation of the first ring gear R1.

[0045] The first switching unit SW1 includes a first switching plate PL1 for switching the position of the first claw CW1. FIG. 4A to FIG. 4C In FIG. 1 , the first switching plate PL1 of the first switching unit SW1 is indicated by a two-dot chain line. The first switching plate PL1 has an annular shape and is movable in the circumferential direction.

[0046] The first switching board PL1 has Figure 4A The position corresponding to the bidirectional limit state shown is Figure 4B The position corresponding to the one-way restriction state shown and Figure 4C The first switching plate PL1 is provided on the worm wheel 32 and rotates together with the worm wheel 32. Therefore, the first switching plate PL1 is driven in the circumferential direction by the actuator 31, thereby switching the position of the first switching plate PL1.

[0047] For example, in Figure 4A When the first switching plate PL1 is driven to rotate at the fixed position on the right side of the state shown, the position of the first switching plate PL1 is switched to Figure 4BThe position corresponds to the one-way restriction state shown. At this time, the first switching part SW1 overcomes the force of the spring to push the front end of the first claw CW1 on the left radially outward, thereby switching the position of the first claw CW1 on the left to a free position. As a result, the first claw CW1 on the left is disengaged from the engaging portion of the first rotating side component RB1, so that the first ring gear R1 is free to rotate in the right direction. On the other hand, in this case, the first claw CW1 on the right is engaged with the engaging portion, so the rotation of the first ring gear R1 in the left direction is locked. Therefore, in this case, the first brake B1 is in a released state with respect to the rotation of the first ring gear R1 in the right direction, and is in a coupled state with respect to the rotation of the first ring gear R1 in the left direction.

[0048] The first switching plate PL1 is Figure 4A When the fixed position on the left side of the state shown is rotated, the position of the first switching plate PL1 is switched to Figure 4C At this time, the first switching unit SW1 overcomes the force of the spring and pushes the front ends of the left and right first claws CW1 radially outward, thereby switching the positions of the left and right first claws CW1 to free positions. As a result, the first ring gear R1 is free to rotate in both left and right directions.

[0049] In this way, the actuator 31 drives the first brake B1 by driving the first switching plate PL1. The actuator 31 can also drive the second brake B2 in the same manner as the first brake B1. The first switching unit SW1 and the second switching unit SW2 of the second brake B2 are configured so that, as described later, the actuator 31 drives the first switching plate PL1. Figure 6 As shown, the first brake B1 and the second brake B2 can change their states. The first brake B1 and the second brake B2 both constitute selectable one-way clutches.

[0050] return Figure 1 The unit 100 further includes a transmission controller 60 and an MG controller 70. The transmission controller 60 and the speed change mechanism 20 together form a transmission TM. The transmission controller 60 is a controller for controlling the transmission TM and constitutes a control device for the transmission TM. The transmission controller 60 and the MG controller 70 for controlling the MG 40 are connected to each other so as to be able to communicate with each other. The unit 100 may also be configured to further include an integrated controller such as the transmission controller 60 and the MG controller 70 that is responsible for integrated control. In addition, the transmission controller 60 and the MG controller 70 may also be configured by a single controller.

[0051] The transmission controller 60 and the MG controller 70 are each composed of one or more computers (microcomputers) having a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), and an input / output interface (I / O interface). These controllers 60 and 70 are controlled by the CPU executing a program stored in the ROM or RAM. As the program, for example, a program stored in a non-temporary storage medium such as a CD-ROM may be used.

[0052] Signals from the sensor / switch group 80 representing various sensors / switches are input to the transmission controller 60. The sensor / switch group 80 includes, for example, a vehicle speed sensor for detecting the vehicle speed VSP, an accelerator opening sensor for detecting the accelerator opening APO, a position sensor for detecting the rotational position of the actuator 31, an input speed sensor for detecting the input speed Nin of the transmission TM, and an output speed sensor for detecting the output speed Nout of the speed change mechanism 20. The input speed Nin is, for example, the speed of the rotating shaft 22, and the output speed Nout is, for example, the speed of the first planetary carrier C1. Other appropriate signals may also be input to the transmission controller 60.

[0053] The transmission controller 60 controls the transmission TM based on the input signal. The transmission TM is controlled by controlling the actuator 31 and the clutch CL based on the input signal.

[0054] In the transmission TM, as the vehicle speed VSP increases, the gears are shifted from the 1st speed to the 2nd speed and from the 2nd speed to the 3rd speed. When the gear shift from the 1st speed to the 2nd speed, i.e., the 1-2 gear shift, the engagement release states of the three engagement elements, namely, the first brake B1, the second brake B2 and the clutch CL, are changed from Figure 3 The state in which only the first brake B1 is engaged is changed to the state in which only the second brake B2 is engaged. Therefore, the first brake B1 becomes the release-side engagement element and the speed change is performed.

[0055] In this case, by using Figure 4A By setting the pawl on the side not bearing torque transmission in the first pawl CW1 of the left and right groups mentioned above to a free position, the first brake B1 can be firstly changed from the two-way restriction state to the one-way restriction state, i.e., the one-way clutch state. And, if the first brake B1 is changed from the one-way clutch state to the release state on this basis, the first brake B1 can be released.

[0056] However, in this case, the first brake B1 is used for meshing and coupling. Therefore, when the torque acts on the first brake B1, the force required for release becomes larger accordingly. As a result, there is a concern that the torque acting on the first brake B1 may prevent smooth release.

[0057] In view of such circumstances, in the present embodiment, the transmission controller 60 performs the control described below.

[0058] Figure 5 1 is a flowchart showing an example of control performed by the transmission controller 60. In step S11, it is determined whether there is a 1-2 shift instruction. Whether there is a 1-2 shift instruction can be determined based on whether the execution condition of the 1-2 shift is satisfied. The execution condition of the 1-2 shift can be an appropriate condition, such as a condition including the vehicle speed VSP. If the determination is negative in step S11, the processing is temporarily terminated. If the determination is positive in step S11, the 1-2 shift is started, and the processing enters step S12, and then enters step S13.

[0059] In step S12, the actuator 31 is driven. As this drive, the first brake B1 is driven to change from the locked / locked state to the locked / free state. The locked / locked state is in other words a two-way restriction state, and the locked / free state is in other words a one-way clutch state.

[0060] In step S13, control is performed to change the clutch CL from a released state to a slipping state. Here, with respect to the clutch CL as a friction engagement element, release refers to a state in which the clutch CL has no torque capacity. In addition, slipping refers to a state in which the clutch CL has torque capacity but there is an input-output rotation difference in the clutch CL. Engagement or full engagement refers to a state in which the clutch CL has torque capacity but there is no input-output rotation difference in the clutch CL.

[0061] The state in which the clutch CL has no torque capacity means, in other words, a state in which the clutch CL does not transmit power, and the state in which the clutch CL has torque capacity means, in other words, a state in which the clutch CL transmits power. With respect to the clutch CL, slip means, in other words, a state in which the torque capacity of the clutch CL is smaller than the input torque, and coupling or full coupling means, in other words, a state in which the torque capacity of the clutch CL is larger than the input torque.

[0062] By setting the clutch CL to the slip state, the clutch CL can share the torque, thereby reducing the torque shared by the first brake B1. In step S13, the clutch CL is controlled to gradually increase the transmission torque of the clutch CL.

[0063] In step S14, it is determined whether the first brake B1 can be released. For example, it is possible to determine whether a pre-set estimated elapsed time has elapsed from the time when the actuator 31 is driven in step S12 to the time when the torque capacity of the first brake B1 becomes zero. If the determination is negative in step S14, the process returns to step S14. If the determination is positive in step S14, the process proceeds to step S15.

[0064] In step S15, the actuator 31 is driven. As this drive, the first brake B1 is driven to change from the locked / free state to the free / free state. In other words, the free / free state is a released state. In step S15, in the state where the clutch CL is slipped in step S13, the actuator 31 of the first brake B1 is driven, and the first brake B1 is changed from the one-way clutch state to the released state. In this way, by increasing the torque share of the clutch CL, the torque share of the first brake B1 can be reduced, so the first brake B1 is released smoothly.

[0065] In step S16, rotation synchronization for engaging the second brake B2 is started. Rotation synchronization is started based on the affirmative determination of step S14. By controlling the clutch CL, the clutch CL is further advanced to the state transition to the engaging side, thereby further increasing the transmission torque of the clutch CL, thereby performing rotation synchronization. As a result, the input speed Nin starts to decrease, and the speed ratio (input speed Nin / output speed Nout) starts to decrease.

[0066] In step S17, it is determined whether the rotation is synchronized. As this determination, it is possible to determine whether the difference between the input speed Nin and the input speed Nin_2nd, which is the input speed Nin corresponding to the second speed, is less than a predetermined value α. The predetermined value α can be pre-set as a determination value for determining whether the input speed Nin is close to the input speed Nin_2nd to the extent that the second brake B2 for meshing engagement can be engaged. If the determination is negative in step S17, the process returns to step S17. If the determination is positive in step S17, the process proceeds to step S18.

[0067] The rotation synchronization is started and terminated in step S18. The rotation synchronization is terminated by reducing the transmission torque of the clutch CL by an amount increased for the rotation synchronization.

[0068] In step S19, it is determined whether the rotation synchronization has been completed. As such, it is possible to determine whether the piston 27 has returned to the rotation synchronization start position based on the amount of work of the electric actuator of the clutch CL, for example. If the determination is negative in step S19, the process returns to step S19. If the determination is positive in step S19, the process proceeds to step S20.

[0069] In step S20, the actuator 31 is driven. As this drive, the second brake B2 is driven to change from the free / free state to the locked / free state. Therefore, the second brake B2 is engaged as a one-way clutch state.

[0070] When the second brake B2 is engaged, the state of the transmission TM needs to be changed in a direction in which the input-output rotation difference is reduced in order to reduce the speed change shock. In response, the clutch CL slips in step S13 and then maintains the slip state until step S21 described later.

[0071] Therefore, the second brake B2 is engaged in the state where the clutch CL is slipping in step S20, so that the clutch CL is slipping when the second brake B2 is engaged. As a result, when the second brake B2 is engaged, the transmission TM changes state in a direction in which the input-output rotational difference decreases.

[0072] After the first brake B1 is switched from the one-way clutch state to the released state in step S15 and before the second brake B2 is engaged in step S20 , the clutch CL slides in a state where the first brake B1 and the second brake B2 are released.

[0073] Thus, a release period is provided for both the first brake B1 and the second brake B2 to prevent interlocking (double engagement state) of the first brake B1 and the second brake B2. In addition, at this time, the clutch CL has a torque capacity, so the feeling of free running of the vehicle is also suppressed.

[0074] In step S21, it is determined whether the speed ratio is the speed ratio of the 2nd speed. The speed ratio of the 2nd speed can be known in advance. If the speed ratio of the 2nd speed is achieved, the torque from the first brake B1 to the second brake B2 via the clutch CL can be switched by making the second brake B2 share the torque shared by the clutch CL, thereby completing the 1-2 speed change. If the determination is negative in step S21, the process returns to step S21. If the determination is positive in step S21, the process proceeds to step S22.

[0075] In step S22, control is performed to change the clutch CL from the slip state to the release state. In this control, the clutch CL is controlled to gradually reduce the transmission torque of the clutch CL. As a result, the second brake B2 can share the torque shared by the clutch CL, and the 1-2 speed change can be completed.

[0076] After the clutch CL is engaged by making the second brake B2 in the one-way clutch state while the clutch CL is slipping in step S20, it is released in step S22. In this way, since the second brake B2 is transferred to the one-way clutch state, the torque from the clutch CL to the second brake B2 is smoothly transferred compared to, for example, the case of transferring to the locked / locked state. After step S22, the process is temporarily terminated.

[0077] Figure 6 It means Figure 5FIG. 1 is a diagram showing an example of a timing diagram corresponding to the processing of the flowchart shown in FIG. 1-2 speed change starts at time T1. When the 1-2 speed change starts, the first brake B1 is first controlled to the one-way clutch state based on the drive of the actuator 31. Therefore, the switching instruction of the first brake B1 changes from the locked / locked state to the locked / free state, and the first brake B1 is controlled according to the switching instruction. When the 1-2 speed change starts, the clutch CL is further controlled to the slip state. As a result, the transmission torque of the clutch CL gradually increases.

[0078] The increase in the transmission torque of the clutch CL means the increase in the torque shared by the clutch CL. Therefore, when the transmission torque of the clutch CL increases, the transmission torque of the brake decreases accordingly. The transmission torque of the brake at this time is the transmission torque of the first brake B1, and the first brake B1 is connected by meshing. Therefore, the torque capacity of the first brake B1 does not change particularly at this time.

[0079] The output torque of the transmission TM is constant. Therefore, when the transmission torque of the clutch CL increases, the input shaft torque of the transmission TM, that is, the torque of the rotating shaft 22, increases accordingly. As a result, the torque ratio (output torque / input torque) of the transmission TM decreases according to the increase in the transmission torque of the clutch CL. When the transmission torque of the brake gradually decreases and becomes zero, only the clutch CL among the first brake B1, the second brake B2 and the clutch CL bears the torque. Therefore, the torque ratio gradually decreases toward the torque ratio of the third speed.

[0080] At time T2 , the transmission torque of the brake is zero, and the torque ratio is that of speed 3. As a result, torque no longer acts on the first brake B1 , and the first claw CW1 of the first brake B1 engaged in the one-way clutch state can be easily disengaged by the actuator 31 .

[0081] Therefore, at time T2, the switching instruction of the first brake B1 changes from the locked / free state to the free / free state, and the first brake B1 is controlled to the free / free state based on the drive of the actuator 31. As a result, the speed is not the 1st speed. However, since the second brake B2 is released at this time, the Figure 3 As can be seen from the above-mentioned engagement table, the speed stage is not 2. At time T2, the transmission torque of the clutch CL also begins to increase further. Thus, the rotation synchronization for the engagement of the second brake B2 begins. As a result, the input speed Nin begins to decrease, and the speed ratio begins to decrease.

[0082] From time T3, the transmission torque of the clutch CL is constant. At time T4, the input speed Nin approaches the input speed Nin_2nd, and the rotation is synchronized. As a result, at time T4, the transmission torque of the clutch CL begins to decrease, and the rotation synchronization begins to end. When the transmission torque of the clutch CL increases during the rotation synchronization, the input shaft torque decreases, and if the transmission torque of the clutch CL decreases, the input shaft torque increases.

[0083] At time T5, the transmission torque of the clutch CL returns to the value of time T2 at time T5, and the rotation synchronization ends. As a result, in order to change the speed stage to the second speed, the switching instruction of the second brake B2 changes from the free / free state to the locked / free state, and the second brake B2 is controlled to the one-way clutch state based on the drive of the actuator 31. The input speed Nin becomes the input speed Nin_2nd at time T5. The torque capacity of the second brake B2 gradually increases when the second brake B2 actually becomes the locked / free state.

[0084] At time T6, the speed ratio is the speed ratio of the 2nd speed. Therefore, the transmission torque of the clutch CL begins to decrease, and accordingly, the transmission torque of the brake begins to increase. As a result, the torque shared by the clutch CL decreases, and the torque shared by the second brake B2 increases, and the torque ratio changes toward the torque ratio of the 2nd speed. The input shaft torque decreases as the transmission torque of the clutch CL decreases.

[0085] At time T7, the transmission torque of the clutch CL becomes zero. As a result, the torque shared by the clutch CL disappears, and the torque switching from the first brake B1 to the second brake B2 via the clutch CL is completed. Therefore, the torque ratio also becomes the torque ratio of the second speed, and the 1-2 speed change is completed.

[0086] Next, the main effects of this embodiment will be described.

[0087] (1) The transmission TM includes the first brake B1 , the second brake B2 , and the clutch CL. The transmission controller 60 drives the actuator 31 of the first brake B1 while the clutch CL is slipping, thereby switching the first brake B1 from the one-way clutch state to the released state and then engaging the second brake B2 .

[0088] According to such a structure, when the first brake B1 as the release side engagement element is changed from the one-way clutch state to the release state, the torque share of the first brake B1 is reduced by increasing the torque share of the clutch CL. As a result, the reaction force applied to the first claw CW1 as the engagement portion of the first brake B1 can be reduced, so the first brake B1 can be released smoothly. In addition, for example, if the torque share of the clutch CL is increased all at once to make it fully engaged, the impact becomes larger. Therefore, it is preferable to set it to a slip state in which the shared torque to be borne is smaller than that of the fully engaged state.

[0089] (2) After the transmission controller 60 changes the first brake B1 from the one-way clutch state to the released state, the second brake B2 is engaged while the clutch CL is slipping. According to such a configuration, when the second brake B2 is engaged, the clutch CL is slipped, so that the transmission TM can be changed to a state in a direction in which the input-output rotational difference is reduced.

[0090] (3) After the first brake B1 is changed from the one-way clutch state to the released state and before the second brake B2 is engaged, the transmission controller 60 causes the clutch CL to slip while the first brake B1 and the second brake B2 are released. According to such a configuration, by providing a release period for both the first brake B1 and the second brake B2, interlocking of the first brake B1 and the second brake B2 can be prevented. In addition, at this time, the clutch CL has a torque capacity, so the feeling of the vehicle running without moving can also be suppressed.

[0091] (4) The transmission controller 60 engages the second brake B2 in the one-way clutch state while the clutch CL is slipping, and then releases the clutch CL. With this configuration, the second brake B2 is shifted to the one-way clutch state, so that torque can be smoothly transferred from the clutch CL to the second brake B2.

[0092] Although the embodiments of the present invention have been described above, the above embodiments merely show a part of application examples of the present invention and are not intended to limit the technical scope of the present invention to the specific structures of the above embodiments.

[0093] For example, in the above-described embodiment, a case where the actuator 31 is provided in common for the first brake B1 and the second brake B2 is described. However, different actuators may be provided for the first brake B1 and the second brake B2.

[0094] Description of Reference Numerals

[0095] 10: Shell

[0096] 20: Speed ​​change mechanism

[0097] 30: Drive device

[0098] 31: Actuator

[0099] 60: Transmission controller (control device, computer)

[0100] 100: Unit

[0101] B1: First brake (first engagement element)

[0102] B2: Second brake (second engagement element)

[0103] CL: Clutch (third engagement element)

[0104] TM: Transmission

Claims

1. A transmission control device, comprising a first engagement element, a second engagement element, and a third engagement element, wherein: By driving the actuator of the first engagement element in a state in which the third engagement element is caused to slide, the second engagement element is engaged after the first engagement element is changed from the one-way clutch state to the released state.

2. The control device for a transmission according to claim 1, characterized in that: After the first engagement element is changed from the one-way clutch state to the released state, the second engagement element is engaged in a state in which the third engagement element is slipped.

3. The control device for a transmission according to claim 2, characterized in that: After the first engagement element is changed from the one-way clutch state to the released state and before the second engagement element is engaged, the third engagement element is slidably moved in a state in which the first engagement element and the second engagement element are released.

4. The control device for a transmission according to claim 2, characterized in that: After the second engagement element is engaged in a one-way clutch state while the third engagement element is slipped, the third engagement element is released.

5. A method for controlling a transmission, comprising: The steps include: By driving the actuator of the first engagement element in a state in which the third engagement element is caused to slide, the second engagement element is engaged after the first engagement element is changed from the one-way clutch state to the released state.

6. A program executable by a computer of a transmission having a first engagement element, a second engagement element, and a third engagement element, characterized in that: By driving the actuator of the first engagement element in a state in which the third engagement element is caused to slide, the second engagement element is engaged after the first engagement element is changed from the one-way clutch state to the released state.

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