JP6555109B2 - Power transmission control device - Google Patents

Description

  The present invention relates to a control device for a power transmission device mounted on a vehicle or the like. In particular, the present invention relates to a control device applied to a power transmission device in which a plurality of power transmission paths are provided in parallel.

  Conventionally, as disclosed in Patent Document 1, as a power transmission device mounted on a vehicle, power transmission is performed by a first power transmission path that transmits power by meshing a gear and a belt-type continuously variable transmission. One in which a second power transmission path is provided in parallel is known.

  This type of power transmission device includes a gear travel clutch and a belt travel clutch. When power is transmitted through the first power transmission path, the gear travel clutch is engaged and the belt travel clutch is released. On the other hand, when power is transmitted through the second power transmission path, the belt travel clutch is engaged and the gear travel clutch is released.

  Incidentally, as disclosed in Patent Document 2, neutral control is known as control of a power transmission device. In this neutral control, when the shift range is the forward travel range, the accelerator operation is not performed, and the vehicle speed is equal to or lower than a predetermined value, the power transmission clutch is released or half-engaged. is there. This reduces the load on the engine and improves the fuel consumption rate. Further, in the case where the engine is stopped when the vehicle is stopped (so-called idling stop), the neutral control is executed prior to stopping the engine, so that the shock generated in the vehicle body when the engine is stopped can be reduced.

Japanese Patent Laying-Open No. 2015-105708 JP 2012-167487 A

  When neutral control is performed in the power transmission device in which the first power transmission path and the second power transmission path described above are provided in parallel, for example, the second power transmission path engaged with the belt travel clutch. When the neutral control execution condition is satisfied in the power transmission state (traveling state at a low vehicle speed), the belt traveling clutch is operated to the disengagement side. In conjunction with this, the gear traveling clutch that has been in the released state is placed in a semi-engaged state in consideration of the response at the next vehicle start-up. That is, the clutch is replaced.

  When the clutch is replaced, if the rotational speed on the output side (drive wheel side) of the gear traveling clutch (hereinafter referred to as the output rotational speed) is higher than the engine rotational speed, the gear traveling clutch As the engine enters the half-engaged state, the engine enters the driven state. For example, the output side rotational speed may be higher than the engine rotational speed due to the fact that the vehicle was traveling before the clutch replacement was started. In this case, the gear traveling clutch As the engine enters the half-engaged state, the engine enters the driven state.

  Thereafter, as the vehicle speed decreases, the torque input from the drive wheel side to the gear travel clutch decreases, and when the engine torque becomes larger than this torque, the engine torque is output to the gear travel clutch. Driving state. That is, the driven state and the driving state of the engine are switched during the neutral control. As a result, the backlash direction caused by the backlash between the gears disposed in the power transmission path is reversed, and there is a risk that rattling noise and shock will occur.

  The present invention has been made in view of such a point, and an object of the present invention is to perform neutral control on a power transmission device in which a first power transmission path and a second power transmission path are provided in parallel. It is providing the control apparatus of the power transmission device which can suppress a rattling noise and shock inside.

In order to achieve the above-mentioned object, the solution means of the present invention provides a power transmission path for transmitting power from a driving force source as a power transmission path toward an output shaft by meshing gears without going through a belt-type continuously variable transmission. a first power transmission path which transmits a second power transmission path transmits power toward the output shaft by way of the belt type continuously variable transmission is provided in parallel, the input of the first clutch A planetary gear device to which power from the driving force source is transmitted is connected to the side, a gear mechanism connected to the output shaft is connected to the output side of the first clutch, and the first clutch is connected to the first clutch. The belt type that is engaged when power is transmitted by a power transmission path and released when power is transmitted by the second power transmission path, and that transmits power from the driving force source. Secondary of continuously variable transmission A second clutch disposed between the over Li and the output shaft, powered by engagement with and the first power transmission path when the second clutch that transmits power by the second power transmission path It is premised on a control device applied to a power transmission device that is released when transmitting. A neutral control execution condition detection unit that detects that a predetermined neutral control execution condition is satisfied in a state where power is transmitted through the second power transmission path to the control device of the power transmission device, and the neutral control When the execution condition detection unit detects that the neutral control execution condition is satisfied, the second clutch is started to be released, and the output speed of the first clutch is set to the input side of the first clutch. A clutch control unit for engaging the first clutch to a state where power can be transmitted.

  The rotation speed on the output side and the rotation speed on the input side of the first clutch referred to here are the friction engagement bodies constituting the first clutch (individually rotated when the first clutch is released and integrated with each other in the engaged state). The rotational speeds of the rotating bodies that rotate integrally with the respective friction engaging bodies that rotate in the same manner. These rotational speeds may be obtained by directly detecting the rotational speed of the rotating body, or other rotating bodies connected to the rotating body (for example, decelerated by a predetermined reduction ratio). You may make it obtain | require by multiplying a rotational speed by a reduction ratio.

  When it is detected by this specific matter that the neutral control execution condition is satisfied in a state where the second clutch is engaged and the first clutch is released and power is transmitted through the second power transmission path, The releasing operation of the second clutch is started. Further, the first clutch is engaged until the power can be transmitted on condition that the rotational speed on the output side of the first clutch is equal to or lower than the rotational speed on the input side of the first clutch. That is, when the rotational speed on the output side of the first clutch exceeds the rotational speed on the input side of the first clutch, the first clutch is not engaged in a state where power can be transmitted. For this reason, the driving force source on the input side of the first clutch is not driven. When the neutral control is started, the torque from the output side of the first clutch decreases as the vehicle speed decreases, and the driving force source in the engaged state (including the semi-engaged state) of the first clutch. However, as described above, since the driving force source is not in the driven state, the driven state and the driving state are not switched during the neutral control. As a result, it is possible to suppress the occurrence of rattling noise and shock due to reverse play of the backlash caused by backlash between the gears arranged in the power transmission path.

  In the present invention, when the neutral control execution condition is satisfied, the first clutch is transmitted with power on the condition that the rotational speed on the output side of the first clutch is equal to or lower than the rotational speed on the input side of the first clutch. It is made to engage until possible. Thus, the driving force source does not enter the driven state, and the driven state and the driving state are not switched during the neutral control. As a result, it is possible to suppress the occurrence of rattling noise and shock between the gears disposed in the power transmission path.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram for explaining a schematic configuration of a power transmission device according to an embodiment. It is a figure which shows the engagement table of the engagement element for every traveling pattern by a power transmission device. It is a block diagram which shows a power transmission device and an engine control system. It is a flowchart figure which shows the procedure of neutral control. It is a timing chart figure showing an example of change of each of engine rotation speed, turbine rotation speed, planetary output shaft rotation speed, C2 clutch oil pressure, and C1 clutch oil pressure in an embodiment. It is a timing chart figure showing an example of change of each of engine rotation speed, turbine rotation speed, planetary output shaft rotation speed, C2 clutch oil pressure, and C1 clutch oil pressure in a comparative example.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a case where the present invention is applied to a power transmission device mounted on a vehicle will be described.

-Schematic configuration of power transmission device-
FIG. 1 is a skeleton diagram for explaining a schematic configuration of a power transmission device 1 according to the present embodiment. The power transmission device 1 transmits torque (power) from the engine 2 that is a driving force source for traveling toward the drive wheels 7L and 7R. This power transmission device 1 includes an output shaft 8 provided with a torque converter 3, a forward / reverse switching device 4, a belt-type continuously variable transmission 5 (hereinafter simply referred to as a continuously variable transmission 5), a gear mechanism 6, and an output gear 81. And a differential device 9 and the like.

  In the power transmission device 1, a first power transmission path that transmits power by meshing gears and a second power transmission path that transmits power by the continuously variable transmission 5 are provided in parallel. Specifically, in the first power transmission path, torque output from the engine 2 is input to the turbine shaft 31 via the torque converter 3, and this torque is transferred from the turbine shaft 31 to the forward / reverse switching device 4 and the gear mechanism 6. Is transmitted to the output shaft 8 via. On the other hand, in the second power transmission path, the torque input to the turbine shaft 31 is transmitted to the output shaft 8 via the continuously variable transmission 5. The power transmission path is switched between the first power transmission path and the second power transmission path in accordance with the traveling state of the vehicle (the configuration for switching the power transmission path will be described later). To do).

  The engine 2 is constituted by an internal combustion engine such as a gasoline engine or a diesel engine. The torque converter 3 includes a pump impeller 32 connected to the crankshaft 21 of the engine 2 and a turbine impeller 33 connected to the forward / reverse switching device 4 via the turbine shaft 31. A lockup clutch 34 is provided between the pump impeller 32 and the turbine impeller 33. When the lockup clutch 34 is completely engaged, the pump impeller 32 and the turbine impeller 33 rotate integrally.

  The forward / reverse switching device 4 includes a forward clutch C1, a reverse brake B1, and a double pinion type planetary gear device 41. The carrier 42 of the planetary gear unit 41 is integrally connected to the turbine shaft 31 and the input shaft 51 of the continuously variable transmission 5, the ring gear 43 is selectively connected to the housing 11 via the reverse brake B1, and the sun gear 44 is It is connected to the small diameter gear 61 via the planetary output shaft 45. Further, the sun gear 44 and the carrier 42 are selectively coupled via the forward clutch C1. Both the forward clutch C1 and the reverse brake B1 are hydraulic friction engagement elements that are frictionally engaged by a hydraulic actuator.

  The gear mechanism 6 includes the small-diameter gear 61 and a large-diameter gear 63 that meshes with the small-diameter gear 61 and is provided on the first counter shaft 62 so as not to be relatively rotatable. An idler gear 64 is provided around the same rotational axis as the first counter shaft 62 so as to be rotatable relative to the first counter shaft 62. Further, a meshing clutch D1 is provided between the first counter shaft 62 and the idler gear 64 to selectively connect and disconnect them. The meshing clutch D1 includes a first gear 65 formed on the first counter shaft 62, a second gear 66 formed on the idler gear 64, and a spline that can mesh with the first gear 65 and the second gear 66. And a hub sleeve 67 formed with teeth. The hub sleeve 67 is engaged with the first gear 65 and the second gear 66 so that the first counter shaft 62 and the idler gear 64 are connected. Further, the meshing clutch D1 includes a synchromesh mechanism (not shown) that synchronizes rotation when the hub sleeve 67 is engaged with both the gears 65 and 66.

  The idler gear 64 is meshed with an input gear 68 having a larger diameter than the idler gear 64. The input gear 68 is provided so as not to rotate relative to the output shaft 8 disposed on the rotation axis common to the rotation axis of the secondary pulley 53 of the continuously variable transmission 5. The output shaft 8 is disposed so as to be rotatable around the rotation axis, and the input gear 68 and the output gear 81 are provided so as not to be relatively rotatable. The forward clutch C1 and the meshing clutch D1 are both engaged, and a belt traveling clutch C2 described later is released, so that the torque of the engine 2 causes the turbine shaft 31, the forward / reverse switching device 4 and the gear mechanism 6 to move. The first power transmission path is formed to be transmitted to the output shaft 8 via. For this reason, the forward clutch C1 is referred to in the present invention as “a first clutch that is engaged when power is transmitted through the first power transmission path and released when power is transmitted through the second power transmission path”. It corresponds to.

  The continuously variable transmission 5 is provided on a power transmission path between the input shaft 51 and the output shaft 8 connected to the turbine shaft 31, and a primary pulley 52 that is an input side member provided on the input shaft 51, A secondary pulley 53 that is an output side member and a transmission belt 54 wound between the pair of pulleys 52 and 53 are provided, and a frictional force between the pair of pulleys 52 and 53 and the transmission belt 54 is generated. Power transmission is performed through.

  The primary pulley 52 includes a fixed sheave 52a that is fixed to the input shaft 51, a movable sheave 52b that is not rotatable relative to the input shaft 51 and is movable in the axial direction, and a space between them. A primary hydraulic actuator 52c that generates a thrust force to move the movable sheave 52b in order to change the V groove width. The secondary pulley 53 has a fixed sheave 53a, a movable sheave 53b that is not rotatable relative to the fixed sheave 53a and capable of moving in the axial direction, and a V groove width therebetween. A secondary hydraulic actuator 53c that generates a thrust force that moves the movable sheave 53b to be changed is provided.

  The actual transmission ratio γ (= input shaft rotational speed Nin / output shaft rotational speed Nout) is obtained by changing the engagement diameter (effective diameter) of the transmission belt 54 by changing the V groove width of the pair of pulleys 52 and 53. Can be changed continuously.

  Further, a belt traveling clutch C2 is provided between the continuously variable transmission 5 and the output shaft 8 so as to selectively connect and disconnect between them. The belt running clutch C2 is a hydraulic friction engagement element that is frictionally engaged by a hydraulic actuator. When the belt traveling clutch C2 is engaged and the forward clutch C1 is released, the torque of the engine 2 is transmitted to the output shaft 8 via the input shaft 51 and the continuously variable transmission 5. A second power transmission path is formed. For this reason, the belt clutch C2 is referred to in the present invention as "a second clutch that is engaged when power is transmitted through the second power transmission path and is released when power is transmitted through the first power transmission path. Is equivalent to.

  The output gear 81 is meshed with a large diameter gear 92 fixed to the second counter shaft 91. The second countershaft 91 is provided with a small diameter gear 94 that meshes with the diffring gear 93 of the differential device 9. The differential device 9 is configured by a known differential mechanism.

-Operation of power transmission device-
Next, the operation of the power transmission device 1 configured as described above will be described using an engagement table of engagement elements for each traveling pattern shown in FIG. In FIG. 2, C1 corresponds to the operating state of the forward clutch C1, C2 corresponds to the operating state of the belt traveling clutch C2, B1 corresponds to the operating state of the reverse brake B1, and D1 corresponds to the meshing clutch D1. Corresponds to the operating state. Further, “◯” indicates engagement (connection), and “×” indicates release (shutoff).

  First, a traveling pattern in which the torque of the engine 2 is transmitted to the output shaft 8 via the gear mechanism 6, that is, a traveling pattern in which the torque is transmitted through the first power transmission path will be described. This traveling pattern corresponds to the gear traveling of FIG. 2, and as shown in FIG. 2, the forward clutch C1 and the meshing clutch D1 are engaged, while the belt traveling clutch C2 and the reverse brake B1 are released.

  As the forward clutch C1 is engaged, the planetary gear device 41 that constitutes the forward / reverse switching device 4 rotates integrally, so that the small-diameter gear 61 rotates at the same rotational speed as the turbine shaft 31. Further, when the meshing clutch D1 is engaged, the first counter shaft 62 and the idler gear 64 are connected to rotate integrally. Therefore, when the forward clutch C1 and the meshing clutch D1 are engaged, the first power transmission path is established, and the torque of the engine 2 is converted to the torque converter 3, the turbine shaft 31, the forward / reverse switching device 4, and the gear mechanism. 6, it is transmitted to the output shaft 8 and the output gear 81 via the idler gear 64 and the input gear 68. Further, the torque transmitted to the output gear 81 is transmitted to the left and right drive wheels 7L and 7R via the large diameter gear 92, the small diameter gear 94, and the differential device 9.

  Next, a traveling pattern in which the torque of the engine 2 is transmitted to the output shaft 8 via the continuously variable transmission 5, that is, a traveling pattern in which the torque is transmitted through the second power transmission path will be described. This travel pattern corresponds to the belt travel (high vehicle speed) in FIG. 2, and as shown in the belt travel in FIG. 2, while the belt travel clutch C2 is engaged, the forward clutch C1, the reverse brake B1, and the meshing The clutch D1 is released.

  Since the secondary pulley 53 and the output shaft 8 are connected by engaging the belt traveling clutch C2, the secondary pulley 53, the output shaft 8 and the output gear 81 rotate integrally. Therefore, when the belt traveling clutch C2 is connected, the second power transmission path is established, and the torque of the engine 2 passes through the torque converter 3, the turbine shaft 31, the input shaft 51, and the continuously variable transmission 5. Is transmitted to the output shaft 8 and the output gear 81. Further, the torque transmitted to the output gear 81 is transmitted to the left and right drive wheels 7L and 7R via the large diameter gear 92, the small diameter gear 94, and the differential device 9. Here, the reason that the mesh clutch D1 is released during the belt traveling is to eliminate dragging of the gear mechanism 6 and the like during the belt traveling and to prevent the gear mechanism 6 and the like from rotating at a high vehicle speed. It is.

  The gear traveling is selected in the low vehicle speed region. The gear ratio (the rotational speed Nin of the turbine shaft 31 / the rotational speed Nout of the output shaft 8) when power is transmitted through the first power transmission path is larger than the maximum speed ratio γmax of the continuously variable transmission 5. Is set to a value. That is, the gear ratio in the first power transmission path is set to a value that is not established in the continuously variable transmission 5. Then, for example, when the running condition of the belt running is established by increasing the vehicle speed V, the belt running is switched. Here, when switching from gear travel to belt travel (high vehicle speed) and when switching from belt travel (high vehicle speed) to gear travel, the belt travel (medium vehicle speed) in FIG. It is done.

  For example, when switching from gear running to belt running (high vehicle speed), the state is changed from the state in which the forward clutch C1 and the meshing clutch D1 corresponding to gear running are engaged to the state in which the belt running clutch C2 and the meshing clutch D1 are engaged. It can be switched transiently. That is, the replacement (stepped transmission) of the forward clutch C1 and the belt travel clutch C2 is started. At this time, the power transmission path is switched from the first power transmission path to the second power transmission path, and the power transmission device 1 is substantially upshifted. Then, after the power transmission path is switched, the meshing clutch D1 is released in order to prevent unnecessary drag and high rotation of the gear mechanism 6 and the like.

  In addition, when switching from belt travel (high vehicle speed) to gear travel, the state is switched from the state in which the belt travel clutch C2 is engaged to the state in which the meshing clutch D1 is engaged in preparation for switching to gear travel. (Prepared for downshift). At this time, the rotation is also transmitted to the sun gear 44 of the planetary gear device 41 via the gear mechanism 6, and from this state, the forward clutch C1 and the belt traveling clutch C2 are replaced (the engagement of the forward clutch C1). When the belt traveling clutch C2 is released), the power transmission path is switched from the second power transmission path to the first power transmission path. At this time, the power transmission device 1 is substantially downshifted.

-Control system-
FIG. 3 is a block diagram showing a control system of the power transmission device 1 and the engine 2. The ECU 100 is configured to include a so-called microcomputer including a CPU, a RAM, a ROM, an input / output interface, and the like. The ECU 100 executes output control of the engine 2, shift control of the continuously variable transmission 5, belt clamping pressure control, control for switching the power transmission path of the power transmission device 1, and the like. Further, as will be described later, the ECU 100 also executes neutral control.

  The ECU 100 includes a signal indicating the rotation angle (position) Acr of the crankshaft 21 detected by the engine rotation speed sensor 110 and the rotation speed (engine rotation speed) Ne of the engine 2, and the turbine shaft detected by the turbine rotation speed sensor 111. 31, a signal representing the rotational speed (turbine rotational speed) Nt, a signal representing the input shaft rotational speed Nin which is the rotational speed of the input shaft 51 of the continuously variable transmission 5 detected by the input shaft rotational speed sensor 112, and output shaft rotation A signal representing the output shaft rotational speed Nout which is the rotational speed of the output shaft 8 corresponding to the vehicle speed V detected by the speed sensor 113, a signal representing the throttle opening θth of the electronic throttle valve detected by the throttle sensor 114, and the accelerator opening The accelerator pedal operation amount detected by the degree sensor 115 is the accelerator pedal operation amount. A signal indicating the cell opening Acc, a signal indicating a brake-on Bon indicating a state in which the foot brake as a service brake detected by the foot brake switch 116 is operated, a lever position of the shift lever detected by the lever position sensor 117 ( Operation position) A signal representing Psh, a signal representing the rotational speed of the planetary output shaft 45 detected by the planetary output shaft rotational speed sensor 118 (the same rotational speed as the sun gear 44 and the small-diameter gear 61) Nc1, etc. are supplied. . Further, the ECU 100 sequentially calculates an actual speed ratio γ (= Nin / Nout) established in the power transmission device 1 based on, for example, the output shaft rotational speed Nout and the input shaft rotational speed Nin.

  Further, from the ECU 100, an engine output control command signal Se for output control of the engine 2, a hydraulic control command signal Sccv for hydraulic control related to the shift of the continuously variable transmission 5, and switching of the power transmission path of the power transmission device 1. The hydraulic control command signal Sswt to the forward / reverse switching device 4 (forward clutch C1, reverse brake B1), belt traveling clutch C2, and meshing clutch D1 is output.

  Specifically, as the engine output control command signal Se, a throttle signal for controlling the opening and closing of the throttle valve of the engine 2, an injection signal for controlling the amount of fuel injected from the injector, An ignition timing signal or the like for controlling the ignition timing is output.

  Further, as the hydraulic control command signal Sccvt, a command signal for driving an SLP solenoid valve (not shown) that regulates the primary hydraulic pressure supplied to the primary hydraulic actuator 52c, and a secondary hydraulic pressure supplied to the secondary hydraulic actuator 53c are adjusted. A command signal for driving an SLS solenoid valve (not shown) to be pressed is output to the hydraulic control circuit 12.

  The primary hydraulic pressure is a hydraulic pressure for adjusting the gear ratio of the continuously variable transmission 5. The secondary hydraulic pressure is a hydraulic pressure for adjusting the belt clamping pressure. That is, the speed ratio control of the continuously variable transmission 5 is such that the speed ratio γ of the continuously variable transmission 5 is controlled so as to be a target speed ratio calculated based on the accelerator opening Acc, the vehicle speed V, the brake signal Bon, and the like. The At this time, the primary hydraulic pressure and the secondary hydraulic pressure are adjusted so as to achieve the target gear ratio of the continuously variable transmission 5 in which the operating point of the engine 2 is on the optimum fuel consumption line while preventing belt slippage of the continuously variable transmission 5. Pressed. From the ECU 100, a command signal for primary command oil pressure for achieving the target primary oil pressure and a command signal for secondary command oil pressure for achieving the target secondary oil pressure are output to the hydraulic pressure control circuit 12. Then, the SLP solenoid valve is operated according to the command signal for the primary command oil pressure, and the SLS solenoid valve is operated according to the command signal for the secondary command oil pressure.

  Further, as the hydraulic control command signal Sswt, each linear solenoid valve for controlling the hydraulic pressure supplied to the hydraulic actuators of the forward clutch C1, the reverse brake B1, the belt traveling clutch C2, the meshing clutch D1, and the synchro mechanism is driven. A command signal or the like is output to the hydraulic control circuit 12. The linear solenoid valve includes an SL1 solenoid valve (not shown) that adjusts the hydraulic pressure for switching between engagement, half-engagement, and release of the forward clutch C1, and engagement and half of the belt travel clutch C2. An SL2 solenoid valve (not shown) that performs hydraulic pressure adjustment for switching between engagement and release is provided. Hereinafter, the hydraulic pressure that is adjusted by the SL1 solenoid valve and switches between forward engagement, half engagement, and release of the forward clutch C1 is referred to as C1 clutch hydraulic pressure. Similarly, the hydraulic pressure that is adjusted by the SL2 solenoid valve and switches between engagement, half-engagement and release of the belt travel clutch C2 is referred to as C2 clutch hydraulic pressure.

-Neutral control-
The power transmission device 1 in the present embodiment can execute neutral control. First, the basic operation of this neutral control will be described.

  The ECU 100 controls the hydraulic control circuit 12 so that the forward clutch C1 and the belt travel clutch C2 are disengaged or half-engaged when a predetermined neutral control execution condition is satisfied, and the clutches C1, C2 Neutral control is performed to reduce or release the engagement force.

  The neutral control execution condition is, for example, that the shift position is “D (drive) position”, the operation amount of the accelerator pedal is zero (the accelerator is in an off state), and the vehicle speed is equal to or less than a predetermined value. The shift position is detected based on the output signal of the lever position sensor 117, the operation amount of the accelerator pedal is detected based on the output signal of the accelerator opening sensor 115, and the vehicle speed is detected based on the output signal of the output shaft rotation speed sensor 113. Is done. Further, a brake ON operation (a brake pedal depression operation) may be added to the neutral control execution condition.

  The neutral control is terminated when a predetermined control termination condition is satisfied. This control end condition is, for example, a case where it is detected that the accelerator pedal is depressed based on an output signal from the accelerator opening sensor 115. If the brake ON operation is a neutral control execution condition, the brake OFF operation is also a control end condition.

  Next, control of the forward clutch C1 and the belt travel clutch C2 during neutral control, which is a feature of the present embodiment, will be described.

  When performing neutral control, when the neutral control execution condition is satisfied in the power transmission state by the second power transmission path engaged with the belt traveling clutch C2, the belt traveling clutch C2 is operated to the disengagement side. By interlocking, the forward clutch C1 in the released state is operated to the engagement side. That is, the clutch is replaced. During the neutral control, for example, the forward clutch C1 is maintained in a half-engaged state.

  If the rotation speed Nc1 of the planetary output shaft 45 is higher than the engine rotation speed Ne when the clutch is replaced, the engine 2 is covered as the forward clutch C1 is half-engaged. It becomes a driving state. As described above, when shifting from belt running to gear running as the vehicle speed decreases, the meshing clutch D1 is engaged during belt running (medium vehicle speed) (the meshing clutch D1 is engaged before the start of clutch switching). The planetary output shaft 45 is also rotating with the rotation of the drive wheels 7L and 7R, and therefore the rotational speed Nc1 of the planetary output shaft 45 may be higher than the engine rotational speed Ne. In this case, when the forward clutch C1 is in a half-engaged state, the engine 2 is driven accordingly.

  Thereafter, as the vehicle speed decreases, the torque input to the forward clutch C1 from the drive wheels 7L, 7R side becomes smaller. When the torque of the engine 2 becomes larger than this torque, the engine torque becomes the forward clutch C1. The drive state is output toward the. That is, the driven state and the driving state of the engine 2 are switched during the neutral control. As a result, the backlash direction caused by the backlash between the gears disposed in the power transmission path is reversed, and there is a risk that rattling noise and shock will occur.

  In view of this point, the present embodiment performs hydraulic control that can suppress rattling noise and shock during neutral control.

  Specifically, it is detected whether or not a neutral control execution condition is satisfied in a state where power is transmitted through the second power transmission path. That is, it is detected whether the neutral control execution condition described above is satisfied in the power transmission state by the second power transmission path in which the belt traveling clutch C2 is engaged and the forward clutch C1 is released.

  When it is detected that the neutral control execution condition is established, the belt travel clutch C2 starts to be released, and the rotational speed on the output side of the forward clutch C1 is the input side of the forward clutch C1. The forward clutch C1 is engaged to a state where power can be transmitted under the condition that the rotational speed is less than or equal to the rotational speed of the first clutch C1. Specifically, on the condition that the rotational speed Nc1 of the planetary output shaft 45 detected by the planetary output shaft rotational speed sensor 118 is equal to or lower than the engine rotational speed Ne detected by the engine rotational speed sensor 110. The forward clutch C1 is engaged until it can transmit power (half-engaged state).

  These operations are executed by the ECU 100.

  For this reason, in the ECU 100, the functional part that performs the operation of detecting whether or not the neutral control execution condition is satisfied in a state where the power is transmitted through the second power transmission path is the neutral control execution condition detection according to the present invention. It is configured as a part. In addition, when the ECU 100 detects that the neutral control execution condition is satisfied, the releasing operation of the belt travel clutch C2 is started, and the rotational speed on the output side of the forward clutch C1 is set to be equal to that of the forward clutch C1. A functional part that executes an operation of engaging the forward clutch C1 to a state where power can be transmitted is configured as a clutch control unit in the present invention on condition that the rotational speed is less than or equal to the input side.

  Hereinafter, a specific procedure of the neutral control will be described with reference to the flowchart of FIG. This flowchart is repeatedly executed every predetermined time after the engine 2 is started.

  First, in step ST1, it is determined whether or not the current vehicle running state is a belt running state (belt running). As described above, the gear traveling is selected in the low vehicle speed region. For this reason, in the determination of step ST1, the rotation of the output shaft 8 detected by the output shaft rotational speed sensor 113 and the lever position of the shift lever detected by the lever position sensor 117 is in the D (drive) position. When the vehicle speed V corresponding to the speed is equal to or higher than a predetermined value (for example, 15 km / h or higher), YES determination is made that the belt is running. The value is not limited to this, and is set as appropriate.

  If the current vehicle running state is not a belt running state (for example, a gear running state) and a NO determination is made in step ST1, neutral control is not performed, and the routine is returned as it is.

  If the current vehicle running state is the belt running state and YES is determined in step ST1, the process proceeds to step ST2, and it is determined whether or not a neutral control execution condition is satisfied. That is, as described above, the neutral control is established when the shift position is the “D (drive) position”, the accelerator pedal operation amount is zero (the accelerator is in the off state), and the vehicle speed is equal to or less than a predetermined value. It is determined whether or not the execution condition is satisfied.

  The operation of this step ST2 is an operation by the "neutral control execution condition detection unit" in the present invention, and that a predetermined neutral control execution condition is established in a state where power is transmitted through the second power transmission path. Corresponds to “detection operation”.

  If the neutral control execution condition is not satisfied and the determination in step ST2 is NO, the neutral control execution request is not made and the process returns.

  If the neutral control execution condition is satisfied and YES is determined in step ST2, the process proceeds to step ST3 where the C2 clutch hydraulic pressure is reduced and fast fill (control of the forward clutch C1) is performed as control of the C1 clutch hydraulic pressure. (Control for temporarily increasing the supply hydraulic pressure in order to prepare for engagement). In this case, a control command signal to the SL2 solenoid valve is transmitted to the hydraulic pressure control circuit 12 so that the C2 clutch hydraulic pressure at which the belt traveling clutch C2 is in the half-engaged state is obtained. In addition, a control command signal to the SL1 solenoid valve is transmitted to the hydraulic control circuit 12 so that the fast fill by the C1 clutch hydraulic pressure is executed.

  Then, it moves to step ST4 and determines whether neutral control execution conditions were cancelled | released. For example, when it is detected based on an output signal from the accelerator opening sensor 115 that the accelerator pedal is depressed, it is determined that the neutral control execution condition has been canceled.

  If the neutral control execution condition is not released, NO is determined in step ST4, and in step ST5, the rotational speed Nc1 of the planetary output shaft 45 is a value obtained by adding a predetermined value α to the engine rotational speed Ne (hereinafter referred to as a rotational speed threshold). ) Determine whether or not The engine speed Ne is calculated based on the output signal of the engine speed sensor 110. Further, the rotational speed Nc1 of the planetary output shaft 45 is calculated based on the output signal of the planetary output shaft rotational speed sensor 118. The predetermined value α is an arbitrary value and is set to 0, for example. The predetermined value α may be a value other than zero. For example, when YES is determined in step ST5 when the rotational speed Nc1 of the planetary output shaft 45 sufficiently decreases with respect to the engine rotational speed Ne, the predetermined value α is set to a negative value. . The predetermined value α in this case is set based on experiments or simulations.

  As the neutral control is started, the rotational speed Nc1 of the planetary output shaft 45 gradually decreases. If this rotational speed Nc1 exceeds the rotational speed threshold, NO is determined in step ST5. Return to step ST4. If the neutral control execution condition is canceled while the rotational speed Nc1 still exceeds the rotational speed threshold value, and if NO is determined in step ST4, the process proceeds to step ST6, and the C2 clutch hydraulic pressure is increased. , C1 clutch hydraulic pressure is returned to 0 and the process returns. In this case, a control command signal to the SL2 solenoid valve is transmitted to the hydraulic pressure control circuit 12 so that the C2 clutch hydraulic pressure at which the belt traveling clutch C2 is engaged is obtained. Further, a control command signal for the SL1 solenoid valve is transmitted to the hydraulic pressure control circuit 12 so that the hydraulic fluid supplied to the C1 clutch is drained.

  If the rotational speed Nc1 of the planetary output shaft 45 has become equal to or lower than the rotational speed threshold without releasing the neutral control execution condition, YES is determined in step ST5, and the process proceeds to step ST7. In step ST7, the C1 clutch hydraulic pressure is increased. In this case, a control command signal to the SL1 solenoid valve is transmitted to the hydraulic pressure control circuit 12 so that the C1 clutch hydraulic pressure at which the forward clutch C1 is in the half-engaged state is obtained.

  The operation of the steps ST3 to ST7 is the operation of the clutch control unit according to the present invention, and when the neutral control execution condition detection unit detects that the neutral control execution condition is satisfied, the second clutch releasing operation And the operation of engaging the first clutch to a state where power can be transmitted on condition that the rotation speed on the output side of the first clutch is equal to or lower than the rotation speed on the input side of the first clutch. Equivalent to.

  Thereafter, in step ST8, the timer provided in the ECU 100 starts counting, and in step ST9, it is determined whether or not the timer counting has ended (time up). The time from the start of the timer count to the end is the time from the start of the increase of the C1 clutch oil pressure until the forward clutch C1 is in the half-engaged state in step ST7. Or is set by simulation.

  If the timer expires and a YES determination is made in step ST9, the process moves to step ST10 and the C2 clutch hydraulic pressure is set to zero. In this case, a control command signal to the SL2 solenoid valve is transmitted to the hydraulic pressure control circuit 12 so that the hydraulic fluid supplied to the belt traveling clutch C2 is drained.

  Thereafter, the process proceeds to step ST11, and it is determined whether or not a return condition (for example, accelerator ON operation, brake OFF operation, etc.) from the neutral control is satisfied. If the return condition is not satisfied, the process waits for the return condition to be satisfied in order to continue the current neutral control execution state.

  On the other hand, if the return condition from the neutral control is satisfied, a YES determination is made in step ST11, the process proceeds to step ST12, and the C1 clutch hydraulic pressure is increased. In this case, a control command signal to the SL1 solenoid valve is transmitted to the hydraulic pressure control circuit 12 so that the C1 clutch hydraulic pressure at which the forward clutch C1 is engaged is obtained.

  Since such hydraulic control is performed, the control device for the power transmission device according to the present invention is configured by the ECU 100 (more specifically, by each functional portion in the ECU 100 described above). This control device is configured to receive signals from the engine rotation speed sensor 110, the output shaft rotation speed sensor 113, the accelerator opening sensor 115, the lever position sensor 117, the planetary output shaft rotation speed sensor 118, and the like as input signals. ing. Further, this control device is configured to output a command signal to the SL1 solenoid valve, the SL2 solenoid valve or the like as an output signal.

  FIG. 5 is a timing chart showing an example of changes in the engine rotation speed Ne, the turbine rotation speed Nt, the planetary output shaft rotation speed Nc1, the C2 clutch oil pressure, and the C1 clutch oil pressure in this embodiment. FIG. 6 is a similar timing chart in the comparative example. In these timing charts, the engine rotational speed Ne is represented by a thick solid line, the turbine rotational speed Nt is represented by a thin solid line, and the planetary output shaft rotational speed Nc1 is represented by a one-dot chain line. A two-dot chain line is a synchronous rotation speed in each traveling state. Moreover, what is shown in these figures shifts to idling stop control which stops an engine after execution of neutral control.

  In the comparative example shown in FIG. 6, when the neutral control execution condition is satisfied, the forward clutch C1 is operated without waiting for the planetary output shaft rotational speed Nc1 to become equal to or lower than the rotational speed threshold value (here, the engine rotational speed Ne). It is actuated to the half-engaged state.

  In this comparative example, the neutral control execution condition is satisfied at the timing t1 in FIG. 6, and the C2 clutch hydraulic pressure is lowered at the timing t1 so that the belt traveling clutch C2 is in a half-engaged state. Further, at timing t2 (a situation where the planetary output shaft rotational speed Nc1 is higher than the engine rotational speed Ne), the C1 clutch hydraulic pressure rises and the forward clutch C1 is operated to the half-engaged state. Further, at timing t3, the C2 clutch hydraulic pressure becomes zero, and the belt traveling clutch C2 is released. As a result, the turbine rotation speed Nt rapidly increases, and at timing t4, the turbine rotation speed Nt exceeds the engine rotation speed Ne, and the engine is in a driven state. Thereafter, as the vehicle speed decreases, the turbine rotation speed Nt also decreases, and the engine is in a driving state at timing t5. That is, in this comparative example, the driven state and the driving state are switched during the neutral control, the backlash direction caused by the backlash between the gears arranged in the power transmission path is reversed, There is a risk of rattling noise and shock. At timing t6, the engine is stopped to shift to idling stop control, and the forward clutch C1 is operated to the engagement side in consideration of responsiveness at the next vehicle start.

  On the other hand, in the neutral control according to the present embodiment, the neutral control execution condition is established at the timing T1 in FIG. Has been. At timing T2, fast fill with C1 clutch oil pressure is executed. At this point (a situation where the rotational speed Nc1 of the planetary output shaft 45 is higher than the engine rotational speed Ne), the forward clutch C1 is not in an engaged state capable of transmitting power.

  At timing T3, when the rotational speed Nc1 of the planetary output shaft 45 reaches the engine rotational speed Ne or less, the C1 clutch hydraulic pressure rises, and the forward clutch C1 is operated to the half-engaged state. At this time, the turbine rotational speed Nt is not rapidly increased, and the driving state of the engine 2 is maintained during the neutral control.

  At time T4, the C2 clutch hydraulic pressure becomes zero, and the belt running clutch C2 is released. Further, at timing T5, the engine is stopped to shift to idling stop control, and the forward clutch C1 is operated to the engagement side in consideration of responsiveness at the next vehicle start.

  Thus, in the neutral control in the present embodiment, the driven state and the driving state of the engine 2 are not switched during the neutral control.

  As described above, in the present embodiment, when it is detected that the neutral control execution condition is satisfied in the state where power is transmitted through the second power transmission path, the belt travel clutch C2 is started to be released. To do. Further, the rotational speed on the output side of the forward clutch C1 (the rotational speed Nc1 of the planetary output shaft 45 in this embodiment) is equal to or lower than the rotational speed on the input side of the forward clutch C1 (the engine rotational speed Ne in this embodiment). The forward clutch C1 is engaged to a state where power can be transmitted on the condition that it has become. That is, when the rotational speed on the output side of the forward clutch C1 exceeds the rotational speed on the input side of the forward clutch C1, the forward clutch C1 is not engaged in a state where power can be transmitted. For this reason, the engine 2 does not enter a driven state. For this reason, the driven state and the driving state of the engine 2 are not switched during the neutral control. As a result, it is possible to suppress the occurrence of rattling noise and shock due to reverse play of the backlash caused by backlash between the gears arranged in the power transmission path.

-Other embodiments-
In the embodiment described above, the rotational speed Nc1 of the planetary output shaft 45 is applied as the rotational speed on the output side of the forward clutch C1, and the engine rotational speed Ne is applied as the rotational speed on the input side of the forward clutch C1. Explained. The present invention is not limited to this. For example, the rotational speed of the first counter shaft 62 or the rotational speed of the output shaft 8 may be applied as the rotational speed on the output side of the forward clutch C1. However, in this case, since these rotational speeds are substituted for the rotational speed Nc1 of the planetary output shaft 45, it is necessary to multiply the reduction ratio with the planetary output shaft 45 and apply it to the present invention. . Further, as the rotational speed on the input side of the forward clutch C1, the turbine rotational speed Nt may be applied, or the rotational speed of the carrier 42 may be applied.

  In the embodiment, the case where the present invention is applied to a vehicle on which only the engine 2 is mounted as a driving force source has been described. The present invention is not limited to this, and can also be applied to a hybrid vehicle in which an engine and an electric motor are mounted as driving force sources, and an electric vehicle in which only an electric motor is mounted as a driving force source.

  In the above-described embodiment, the engine rotational speed Ne, the turbine rotational speed Nt, and the rotational speed Nc1 of the planetary output shaft 45 are all detected by the sensors. However, these rotational speeds are estimated using various parameters. It may be a thing.

  The present invention provides a neutral control of a power transmission device in which a first power transmission path for transmitting power by meshing gears and a second power transmission path for transmitting power by a belt-type continuously variable transmission are provided in parallel. It is applicable to.

DESCRIPTION OF SYMBOLS 1 Power transmission device 12 Hydraulic control circuit 2 Engine (drive power source)
45 Planetary output shaft 100 ECU
110 engine speed sensor 113 output shaft speed sensor 115 accelerator opening sensor 117 lever position sensor 118 planetary output shaft speed sensor C1 forward clutch (first clutch)
C2 Belt travel clutch (second clutch)

Claims (1)

As power transmission path for transmitting power from the driving power source, a first power transmission path and transmits power toward the output shaft by meshing of gears without passing through the belt type continuously variable transmission, Mu said belt A second power transmission path for transmitting power toward the output shaft via a step transmission is provided in parallel;
A planetary gear device to which power from the driving force source is transmitted is connected to the input side of the first clutch, and a gear mechanism connected to the output shaft is connected to the output side of the first clutch. Is engaged when transmitting power through the first power transmission path and released when transmitting power through the second power transmission path ,
A second clutch is provided between a secondary pulley of the belt-type continuously variable transmission to which power from the driving force source is transmitted and the output shaft, and the second clutch is powered by the second power transmission path. A control device applied to a power transmission device that is engaged when transmitting power and is released when power is transmitted by the first power transmission path;
A neutral control execution condition detection unit for detecting that a predetermined neutral control execution condition is established in a state where power is transmitted through the second power transmission path;
When the neutral control execution condition detection unit detects that the neutral control execution condition is established, the second clutch is started to be released, and the rotational speed on the output side of the first clutch is determined by the first clutch. A control device for a power transmission device, comprising: a clutch control unit that engages the first clutch to a state where power can be transmitted on the condition that the rotational speed is less than or equal to the input side rotational speed.

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