JP2011220354A - Control device for power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress resonance by eliminating oil pressure shortage in a clamping means in a power transmission device.SOLUTION: A control device for a power transmission device is applied to a power transmission device that transmits a power output from a power source such as an engine to driving wheels. The power transmission device has the clamping means. As the clamping means, a friction engagement device, a pulley, etc., for example, can be available. The control device for a power transmission device has a control means. The control means increases a clamping force of the clamping means by controlling a driving current of an electric oil pump during resonance. Here, the control means makes a value of the driving current of the electric oil pump larger than a rated value during a predetermined period of time.

Description

  The present invention relates to a control device for a power transmission device provided in a vehicle.

  As this type of technology, the following Patent Document 1 detects the occurrence of a resonance phenomenon when the occurrence of a resonance phenomenon in a drive system including an internal combustion engine and a damper and / or a torque limiter and an electric motor is detected. A technique is described in which the motoring of the internal combustion engine is stopped when an integrated value obtained by integrating the number of times and time exceeds a predetermined value. Patent Document 2 describes a technique for increasing the clamping pressure of a belt with the occurrence of a booming noise. Patent Document 3 describes a technique for supplying oil discharged from an electric pump to an automatic transmission when the discharge pressure of a mechanical pump is less than a predetermined value. Patent Document 4 also describes a technique related to the present invention.

JP 2005-233160 A JP 2008-95848 A JP 2000-46165 A JP-A-11-257476

  By the way, in the technique described in Patent Document 1, when suppressing the resonance, the engagement pressure of the clutch is increased and the torque limiter is slid. However, if the hydraulic pressure is insufficient, a desired engagement pressure cannot be obtained. There is a possibility that continuous slip occurs between two members engaged with each other in the clutch, and durability of the clutch is lowered. In particular, when the motor is running, an electric oil pump is used as a hydraulic pressure supply source. In this regard, Patent Documents 2 to 4 do not describe anything.

  This invention is made | formed in view of said point, and makes it a subject to prevent the fall of durability of pinching means, such as a clutch and a pulley, in a power transmission device.

  In one aspect of the present invention, there is provided a power transmission device that is applied to a power transmission device that includes a clamping unit and an electric oil pump that is a hydraulic source of the clamping unit and that transmits power output from a power source. The control device includes a control unit that increases a clamping pressure of the clamping unit by controlling a drive current of the electric oil pump at the time of resonance, and the control unit is configured to control the electric oil pump for a predetermined time. Make the drive current value larger than the rated value.

  The control device for the power transmission device described above is applied to a power transmission device that transmits power output from a power source such as an engine to driving wheels or the like. The power transmission device includes a clamping unit. Examples of the clamping means include a friction engagement device and a pulley. The control device of the power transmission device is realized by, for example, an ECU (Electronic Controlled Unit) and includes a control unit. The control means increases the clamping pressure of the clamping means by controlling the drive current of the electric oil pump during resonance. For example, when the pinching means is a friction engagement device, the control means increases the hydraulic pressure of the friction engagement device to increase the engagement pressure. Here, the control means makes the value of the drive current of the electric oil pump larger than the rated value for a predetermined time. By doing in this way, the fall of durability of a pinching means can be prevented.

  In another aspect of the control device for the power transmission device, the power transmission device includes a mechanical oil pump that uses an engine and an electric motor as the power source, and changes a hydraulic pressure in accordance with the rotational speed of the engine, The control means starts the mechanical oil pump by starting the engine. Even if the engagement pressure is insufficient even though the value of the driving current of the electric oil pump is larger than the rated value, the durability of the clamping means is prevented from being lowered by doing so. be able to.

  A control device for a power transmission device applied to a power transmission device that includes a clamping means and an electric oil pump that is a hydraulic pressure source of the clamping means and that transmits power output from a power source. Control means for increasing the clamping pressure of the clamping means by controlling the driving current of the electric oil pump, and the control means sets the value of the driving current of the electric oil pump from a rated value for a predetermined time. Also make it bigger. By doing in this way, the fall of durability of a pinching means can be prevented.

It is a lineblock diagram of the power transmission device concerning this embodiment. It is a figure which shows the engagement action | operation table | surface in a friction engagement apparatus. It is a collinear diagram which shows the relative relationship of the rotational speed of each rotation element in a power transmission device. It is an example of the signal input from ECU and the signal output from ECU. It is a shift diagram used in the shift control of the mechanical transmission unit. It is a figure which shows the arrangement | sequence of a shift position. It is a time chart which shows an example of the control method of the power transmission device which concerns on this embodiment. It is a flowchart which shows the control processing of the power transmission device which concerns on this embodiment.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

[Device configuration]
First, an example of a configuration of a vehicle power transmission device 10 according to the present embodiment will be described with reference to FIG.

  FIG. 1 is a configuration diagram of a power transmission device 10 for a vehicle. The power transmission device 10 mainly includes an input shaft 14, a damper 51 with a torque limiter, a continuously variable transmission unit 11, a mechanical transmission unit 20, and an output shaft 22. The power transmission device 10 is suitably used for an FR (front engine / rear drive) type vehicle that is vertically installed in a hybrid vehicle, for example. The power transmission device 10 is provided between an engine 8 serving as a driving force source for traveling and a pair of driving wheels (not shown). The engine 8 is an internal combustion engine such as a gasoline engine or a diesel engine, and is connected to the input shaft 14. The drive wheel is connected to the output shaft 22. Since the power transmission device 10 is configured symmetrically with respect to its axis, the lower side is omitted in FIG. The input shaft 14 is an input rotating member disposed on a common axis in a transmission case 12 (hereinafter referred to as the case 12) as a non-rotating member attached to the vehicle body. The continuously variable transmission unit 11 is an electrical transmission unit that is indirectly connected to the input shaft 14 via a damper 51 with a torque limiter. The mechanical transmission unit 20 is a stepped transmission that is connected in series via a transmission member (transmission shaft) 18 through a power transmission path between the continuously variable transmission unit 11 and a drive wheel (not shown). It is a transmission unit that functions as a machine. The output shaft 22 is an output rotating member connected to the mechanical transmission unit 20.

  The continuously variable transmission 11 includes a first electric motor M1, a power distribution mechanism 16, and a second electric motor M2. The power distribution mechanism 16 is a mechanical mechanism that mechanically distributes the output of the engine 8 input to the input shaft 14, and functions as a differential mechanism that distributes the output of the engine 8 to the first electric motor M1 and the transmission member 18. To do. The second electric motor M2 is provided to rotate integrally with the transmission member 18. The second electric motor M2 may be provided in any part constituting the power transmission path from the transmission member 18 to the drive wheel. The first motor M1 and the second motor M2 are so-called motor generators that also have a power generation function, but the first motor M1 has at least a generator (power generation) function for generating a reaction force, and the second motor M2 is used for traveling. At least a motor (electric motor) function for outputting driving force as a driving force source.

The power distribution mechanism 16 is mainly configured by a single pinion type first planetary gear device 24 having a predetermined gear ratio ρ1 of about “0.418”, for example. The first planetary gear unit 24 includes a first sun gear S1, a first planetary gear P1, a first carrier CA1 that supports the first planetary gear P1 so as to rotate and revolve, and a first sun gear via the first planetary gear P1. A first ring gear R1 meshing with S1 is provided as a rotating element (element). When the number of teeth of the first sun gear S1 is ZS1 and the number of teeth of the first ring gear R1 is ZR1, the gear ratio ρ1 is ZS1 / ZR.
1.

  In the power distribution mechanism 16, the first carrier CA1 is connected to the input shaft 14 via a damper 51 with a torque limiter, the first sun gear S1 is connected to the first electric motor M1, and the first ring gear R1 is transmitted. It is connected to the member 18. The power distribution mechanism 16 has a differential state in which the first sun gear S1, the first carrier CA1, and the first ring gear R1, which are the three elements of the first planetary gear device 24, are relatively rotatable with respect to each other so that a differential action works. Is done. Therefore, the output of the engine 8 is distributed to the first electric motor M1 and the transmission member 18, and the electric energy generated from the first electric motor M1 is stored in a part of the distributed output of the engine 8, or The second electric motor M2 is rotationally driven. Thus, the continuously variable transmission unit 11 (power distribution mechanism 16) is in a so-called continuously variable transmission state (electric CVT state), and continuously changes the rotation of the transmission member 18 regardless of the predetermined rotation of the engine 8. Is possible.

  The mechanical transmission unit 20 includes a single pinion type second planetary gear device 26, a single pinion type third planetary gear device 28, and a single pinion type fourth planetary gear device 30. The second planetary gear unit 26 includes a second sun gear S2, a second planetary gear P2, a second carrier CA2 that supports the second planetary gear P2 so as to be capable of rotating and revolving, and a second planetary gear P2. A second ring gear R2 meshing with the sun gear S2 is provided, and has a predetermined gear ratio ρ2 of about “0.562”, for example. The third planetary gear device 28 includes a third sun gear S3 via a third sun gear S3, a third planetary gear P3, a third carrier CA3 that supports the third planetary gear P3 so as to rotate and revolve, and a third planetary gear P3. A third ring gear R3 that meshes with the gear, and has a predetermined gear ratio ρ3 of, for example, about “0.425”. The fourth planetary gear unit 30 includes a fourth sun gear S4, a fourth planetary gear P4, a fourth carrier gear CA4 that supports the fourth planetary gear P4 so as to rotate and revolve, and a fourth sun gear S4 via the fourth planetary gear P4. And has a predetermined gear ratio ρ4 of about “0.421”, for example. The number of teeth of the second sun gear S2 is ZS2, the number of teeth of the second ring gear R2 is ZR2, the number of teeth of the third sun gear S3 is ZS3, the number of teeth of the third ring gear R3 is ZR3, the number of teeth of the fourth sun gear S4 is ZS4, When the number of teeth of the fourth ring gear R4 is ZR4, the gear ratio ρ2 is ZS2 / ZR2, the gear ratio ρ3 is ZS3 / ZR3, and the gear ratio ρ4 is ZS4 / ZR4.

  In the mechanical transmission unit 20, the second sun gear S2 and the third sun gear S3 are integrally connected and selectively connected to the transmission member 18 via the second clutch C2 and the case via the first brake B1. 12 is selectively connected. The second carrier CA2 is selectively connected to the case 12 via the second brake B2, and the fourth ring gear R4 is selectively connected to the case 12 via the third brake B3. The second ring gear R2, the third carrier CA3, and the fourth carrier CA4 are integrally connected to the output shaft 22, and the third ring gear R3 and the fourth sun gear S4 are integrally connected to the first clutch C1. Is selectively connected to the transmission member 18.

  The first clutch C1, the second clutch C2, the first brake B1, the second brake B2, and the third brake B3 are hydraulic friction engagement devices that are often used in conventional vehicular automatic transmissions. These hydraulic friction engagement devices are devices that apply a hydraulic pressure to generate a frictional force between two members (for example, clutches) and engage the two members with each other. Examples of the hydraulic friction engagement device include a wet multi-plate type in which a plurality of friction plates stacked on each other are pressed by a hydraulic actuator, and one or two bands wound around the outer peripheral surface of a rotating drum. One end of each has a band brake or the like that is tightened by a hydraulic actuator, and selectively connects the members on both sides of the band brake.

  The vehicle also includes a first controller 31, a second controller 32, a power storage device 33, a hydraulic control device 34, and an ECU (Electronic Controlled Unit) 40.

  The first controller 31 is for controlling the first electric motor M1, and the second controller 32 is for controlling the second electric motor M2. These controllers 31 and 32 are mainly composed of inverters, for example, and control the motors M1 and M2 corresponding to the motors M1 and M2 to function as electric motors or function as generators, respectively. And is configured to control torque. The electric motors M1 and M2 are connected to the power storage device 33 via the controllers 31 and 32, respectively. The power storage device 33 is a device that supplies electric power to the electric motors M1 and M2 and stores the electric power when the electric motors M1 and M2 function as generators. And a capacitor.

  The hydraulic control device 34 is for controlling the engagement pressure and release pressure of each clutch and brake. The hydraulic control device 34 adjusts the hydraulic pressure generated by an oil pump (not shown) to the line pressure, and controls the engagement pressure of each friction engagement device using the line pressure as a source pressure, or the friction engagement device. Controls the release pressure when releasing. As the hydraulic control device 34, specifically, a hydraulic control device used in a conventional automatic transmission can be employed.

  As will be described in detail later, the ECU 40 has a CPU, R0M, RAM, an input / output interface, and the like, and controls the entire power transmission device 10 by controlling the controllers 31, 32 and the hydraulic control device 34 with electric signals. To do.

  In the power transmission device 10 configured as described above, the first clutch C1, the second clutch C2, the first brake B1, the second brake B2, and the third brake B3 are selectively engaged and operated. Either the first gear (first gear: 1st) to the fourth gear (fourth gear: 4th), the reverse gear (reverse gear: R), or neutral (N) is selectively used. A transmission gear ratio Y (= input shaft rotational speed NIN / output shaft rotational speed N0UT) which is established and changes substantially in an equal ratio is obtained for each gear stage. FIG. 2 shows these engagement operation tables. In the engagement operation table shown in FIG. 2, a circle indicates that the engagement state is established, and no mark indicates that the engagement state is released.

  As shown in the engagement operation table of FIG. 2, the first gear (1st) is established by the engagement of the first clutch C1 and the third brake B3, and the engagement of the first clutch C1 and the second brake B2 is established. The second speed gear stage (2nd) is established, and the third speed gear stage (3rd) is established by engagement of the first clutch C1 and the first brake B1. Further, the fourth gear (4th) is established by the engagement of the first clutch C1 and the second clutch C2, and the reverse gear (Rev by the transmission) is established by the engagement of the second clutch C2 and the third brake B3. It is established. Here, as shown in FIG. 2, as a mode in which the vehicle is moved backward, there is a mode (Rev by M2) by the second electric motor M2 in addition to the mode in which the mechanical transmission unit 20 is driven by the reverse gear. In this case, the second electric motor M2 is reversely rotated so that the vehicle moves backward with the engagement of the first clutch C1 and the third brake B3 established. When the neutral “N” state is set, all the engagement mechanisms are released.

  FIG. 3 is a collinear diagram showing the relative relationship between the rotational speeds of the rotating elements in the power transmission device 10. The collinear chart of FIG. 3 is a two-dimensional coordinate system including a horizontal axis indicating the relationship of the gear ratio ρ of each planetary gear unit 24, 26, 28, and 30 and a vertical axis indicating the relative rotational speed. In FIG. 3, the lower horizontal line X1 of the three horizontal lines indicates the rotational speed “0”, and the upper horizontal line X2 indicates the rotational speed “1.0”, that is, the rotational speed of the engine 8 connected to the input shaft 14. Ne, and the horizontal line XG indicates the rotational speed of the transmission member 18.

  The three vertical lines Y1, Y2, Y3 corresponding to the three elements of the power distribution mechanism 16 constituting the continuously variable transmission unit 11 are the first sun gear S1, the first sun gear S1, and the second It shows the relative rotational speeds of the first carrier CA1 corresponding to the first rotation element RE1 and the first ring gear R1 corresponding to the third rotation element RE3. The intervals between the vertical lines Y1, Y2, Y3 are determined according to the gear ratio ρ1 of the first planetary gear unit 24. Further, the five vertical lines Y4, Y5, Y6, Y7, Y8 of the mechanical transmission unit 20 are, in order from the left, the fourth rotation element RE4, the fifth rotation element RE5, the sixth rotation element RE6, and the seventh rotation element. RE7 and the eighth rotation element RE8 are shown. Here, the fourth rotating element RE4 is the second sun gear S2 and the third sun gear S3 that are connected to each other, the fifth rotating element RE5 is the second carrier CA2, and the sixth rotating element RE6 is the fourth sun gear S3. Ring gear R4. The seventh rotating element RE7 is a second ring gear R2, a third carrier CA3, and a fourth carrier CA4 that are connected to each other. The eighth rotating element RE8 is a third ring gear R3, a fourth carrier CA4 that are connected to each other. Sun gear S4. The intervals between the vertical lines Y4, Y5, Y6, Y7, and Y8 are determined according to the gear ratios ρ2, ρ3, and ρ4 of the second, third, and fourth planetary gear devices 26, 28, and 30, respectively. In the relationship between the vertical axes of the nomograph, if the distance between the sun gear and the carrier corresponds to “1”, the distance between the carrier and the ring gear corresponds to the gear ratio ρ of the planetary gear device. That is, in the continuously variable transmission 11, the interval between the vertical lines Y1 and Y2 is set to an interval corresponding to “1”, and the interval between the vertical lines Y2 and Y3 is set to an interval corresponding to the gear ratio ρ1. . Further, in the mechanical transmission unit 20, the interval between the sun gear and the carrier is set for each of the second, third, and fourth planetary gear devices 26, 28, and 30 so as to correspond to “1”. Is set to an interval corresponding to the gear ratio ρ.

  If expressed using the collinear diagram of FIG. 3 described above, the power transmission device 10 in the power distribution mechanism 16 (the continuously variable transmission 11) is the first rotating element RE1 (first carrier C) of the first planetary gear device 24. A1) is connected to the input shaft 14, that is, the engine 8, the second rotating element RE2 is connected to the first electric motor M1, and the third rotating element (first ring gear R1) RE3 is connected to the transmission member 18 and the second electric motor M2. ing. Thereby, the rotation of the input shaft 14 is transmitted to the mechanical transmission unit 20 via the transmission member 18. At this time, the relationship between the rotational speed of the first sun gear S1 and the rotational speed of the first ring gear R1 is indicated by an oblique straight line L0 passing through the intersection of Y2 and X2.

  Further, when the rotational speed of the first sun gear S1 indicated by the intersection of the straight line L0 and the vertical line Y1 is increased or decreased by controlling the reaction force generated by the power generation of the first electric motor M1, the straight line L0 and the vertical line Y3 The rotational speed of the first ring gear R1 indicated by the intersection point decreases or increases.

  In the mechanical transmission unit 20, the fourth rotating element RE4 is selectively connected to the transmission member 18 via the second clutch C2 and is selectively connected to the case 12 via the first brake B1. Yes. The fifth rotation element RE5 is selectively connected to the case 12 via the second brake B2, and the sixth rotation element RE6 is selectively connected to the case 12 via the third brake B3. The seventh rotation element RE7 is coupled to the output shaft 22, and the eighth rotation element RE8 is selectively coupled to the transmission member 18 via the first clutch C1.

  In the mechanical transmission unit 20, as described above, the first gear (1st) is established by the engagement of the first clutch C1 and the third brake B3. At this time, the rotation speed of the sixth rotation element RE6 is “0”, and the rotation speed of the eighth rotation element RE8 is equal to the rotation speed of the third rotation element RE3. Therefore, in FIG. 3, an oblique straight line L1 passing through the intersection of the vertical line Y8 and the horizontal line XG and the intersection of the vertical line Y6 and the horizontal line X1 is an alignment chart of the first speed gear stage. In addition, the intersection of the straight line L1 and the vertical line Y7 has shown the rotational speed of the output shaft 22 when a 1st-speed gear stage is.

  The second gear (2nd) is established by engagement of the first clutch C1 and the second brake B2. At this time, the fifth rotation element RE5 is “0”, and the rotation speed of the eighth rotation element RE8 is equal to the rotation speed of the third rotation element RE3. Accordingly, in FIG. 3, an oblique straight line L2 passing through the intersection of the vertical line Y8 and the horizontal line XG and the intersection of the vertical line Y5 and the horizontal line X1 is a collinear diagram of the second speed gear stage. The intersection of the straight line L2 and the vertical line Y7 indicates the rotation speed of the output shaft 22 when the second speed gear stage.

  A third gear (3rd) is established by engagement of the first clutch C1 and the third brake B3. At this time, the fourth rotation element RE4 is “0”, and the rotation speed of the eighth rotation element RE8 is equal to the rotation speed of the third rotation element RE3. Therefore, in FIG. 3, an oblique straight line L3 passing through the intersection of the vertical line Y8 and the horizontal line XG and the intersection of the vertical line Y4 and the horizontal line X1 is an alignment chart of the third speed gear stage. The intersection of the straight line L3 and the vertical line Y7 indicates the rotational speed of the output shaft 22 when the third speed gear stage.

  A fourth gear (4th) is established by engagement of the first clutch C1 and the second clutch C2. At this time, the rotation speeds of the fourth rotation element RE4 and the eighth rotation element RE8 are equal to the rotation speed of the third rotation element RE3. Accordingly, in FIG. 3, the straight line L4 along the horizontal line XG is a collinear diagram of the fourth speed gear stage. The intersection of the straight line L4 and the vertical line Y7 indicates the rotational speed of the output shaft 22 when the fourth speed gear stage.

  The reverse gear stage (Rev) by the transmission is established by the engagement of the second clutch C2 and the third brake B3. At this time, the rotation speed of the fourth rotation element RE4 is equal to the rotation speed of the third rotation element RE3, and the rotation speed of the sixth rotation element RE6 is “0”. Accordingly, in FIG. 3, an oblique straight line LR passing through the intersection of the vertical line Y4 and the horizontal line XG and the intersection of the vertical line Y6 and the horizontal line X1 is a collinear diagram of the reverse gear stage. The intersection of the straight line LR and the vertical line Y7 indicates the rotational speed of the output shaft 22 when the reverse gear stage.

  Next, the control of the ECU 40 will be described with reference to FIG. FIG. 4 illustrates signals input to the ECU 40 and signals output from the ECU 40.

  The ECU 40 includes a so-called microcomputer including a CPU, R0M, RAM, and an input / output interface. The ECU 40 performs signal processing according to a program stored in advance in R0M while using the temporary storage function of the RAM, thereby performing drive control such as hybrid drive control for the engine 8, the motors M1 and M2, and the shift control for the mechanical transmission unit 20. Is to execute. The ECU 40 receives signals from the sensors and switches as shown on the left side of FIG. 4 and transmits control signals as shown on the right side of FIG. 4 to each device based on the received signals.

  The ECU 40 receives signals from sensors, switches, and the like as shown on the left side of FIG. For example, the ECU 40 receives a signal indicating the engine water temperature from the engine water temperature sensor, receives a signal indicating the oil pressure of the first brake B1 from the Pb1 oil pressure sensor, and receives a signal indicating the oil pressure of the second brake B2 from the Pb2 oil pressure sensor. Then, a signal indicating the hydraulic pressure of the third brake B3 is received from the Pb3 hydraulic pressure sensor. The ECU 40 receives a signal indicating the rotation speed of the first motor from the M1 rotation speed sensor, receives a signal indicating the rotation speed of the second motor from the M2 rotation speed sensor, and indicates a signal indicating the engine speed Ne from the crank angle sensor. Receive. The ECU 40 receives a signal indicating the towing mode from the towing switch, receives a signal indicating the M mode from the M (motor running) mode switch, receives an air conditioner signal indicating the operation of the air conditioner from the air conditioner switch, and detects the vehicle speed sensor. A signal indicating the vehicle speed corresponding to the rotational speed of the output shaft 22 is received.

  Further, the ECU 40 receives an oil temperature signal indicating the hydraulic oil temperature (AT oil temperature) of the mechanical transmission unit 20 from the AT oil temperature sensor, and receives a setting signal indicating ECT (Electronic Controlled Transmission) mode setting from the ECT switch. A signal indicating a side brake operation from the side brake switch, a signal indicating a foot brake operation from the foot brake switch, a catalyst temperature signal indicating a catalyst temperature from the catalyst temperature sensor, and an accelerator opening sensor. An accelerator opening signal indicating the amount of operation of the accelerator pedal corresponding to the driver's required output amount is received. The ECU 40 receives a signal indicating the electric travel mode from the EV switch, receives a snow mode setting signal indicating the snow mode setting from the snow mode switch, and receives an acceleration signal indicating the longitudinal acceleration of the vehicle from the vehicle acceleration sensor. The ECU 40 receives an auto cruise signal indicating auto cruise traveling from the auto cruise setting switch, receives a setting signal indicating power mode setting from the power mode setting switch, and receives a signal indicating the shift position from the shift position sensor.

  The ECU 40 transmits a control signal to each device as shown on the right side of FIG. For example, the ECU 40 transmits a control signal for operating the opening of the electronic throttle valve to the throttle actuator, transmits a control signal for adjusting the supercharging pressure to the turbocharger, and controls for operating the electric air conditioner. A signal is transmitted to the electric air conditioner, and a control signal for instructing the ignition timing of the engine 8 is transmitted to the ignition device. The ECU 40 transmits a control signal instructing the operation of the electric motors M1 and M2 to the first and second controllers, transmits a control signal for adjusting the amount of electric power that can be stored and discharged, to the power storage device, and the gear ratio. Is transmitted to the gear ratio indicator, and a snow mode display signal for displaying the snow mode is transmitted to the snow mode indicator. The ECU 40 transmits a control signal for adjusting the hydraulic pressure to the AT line pressure control solenoid and the AT solenoid, and transmits an ABS operation signal for preventing slippage of the vehicle during braking to the ABS actuator, and the M mode is selected. An M-mode display signal for indicating that this is being performed is transmitted to the M-mode indicator. The ECU 40 transmits a control signal for operating the mechanical oil pump and the electric oil pump, which are hydraulic sources of the hydraulic control device 34, to the mechanical oil pump and the electric oil pump. The ECU 40 transmits a control signal for driving the electric heater to the electric heater, transmits a control signal for cruise control to the cruise control computer, and adjusts the fuel injection amount supplied into the cylinder of the engine 8. A control signal is supplied to the fuel injection device.

  FIG. 5 shows a shift diagram used in the shift control of the mechanical transmission unit 20, where the vehicle speed is taken on the horizontal axis, the output torque is taken on the vertical axis, and the speed range is set using these vehicle speed and output torque as parameters. Is stipulated.

  A solid line in FIG. 5 indicates an upshift line, and serves as a boundary between shift speed regions when the upshift is performed. Further, the broken line in FIG. 5 indicates a downshift line, which is a boundary between the respective shift speed regions when downshifting. Moreover, the area | region enclosed with a dashed-dotted line is a motor driving | running | working (EV driving | running | working) area | region, and driving | running | working is performed by the motor M2, for example, in the state where the engine 8 is not operating. All of these shift speeds can be set when the drive range (drive position) is selected, but in the manual shift mode (manual mode), the shift speed on the high speed side is limited.

  FIG. 6 shows an arrangement of shift positions in the shift device 42 that outputs a shift position signal to the ECU 40. Parking (P), reverse speed (R: reverse), neutral (for maintaining the vehicle in a stopped state) N) Each position of the drive (D) is arranged almost linearly. This arrangement direction is, for example, a direction along the front-rear direction of the vehicle. A manual position (M) is provided at a position adjacent to the drive position in the width direction of the vehicle, and an upshift position (+) and a downshift position (− ) And are provided. Each of these shift positions is connected by a guide groove 44 that guides the shift lever 43. Therefore, by moving the shift lever 43 along the guide groove 44, an appropriate shift position is selected, and the selected shift position is selected. A position signal is input to the ECU 40.

  When the drive position is selected, all the forward gears from the first gear to the fourth gear in the mechanical transmission unit 20 are set according to the traveling state. On the other hand, when the shift lever 43 is moved from the drive position to the manual position, the drive position is maintained, and shifting up to the fourth gear is possible. Each time the lever 43 is moved, a downshift signal (downrange signal) is output, the third range in which the fourth gear or higher is prohibited, the third range in which the third or higher gear is prohibited, and the first gear It is possible to switch to the L range fixed to. Each time an upshift position is selected, an upshift signal (uprange signal) is output, and the range is sequentially switched to the high speed side.

  When a vehicle equipped with the power transmission device 10 described above travels, for example, torque that periodically varies from the driving wheels due to road surface unevenness or the like is input. When the frequency matches the resonance frequency specific to the power transmission device 10 or the vehicle, resonance occurs and vibration increases. At this time, in the friction engagement device, continuous slip may occur between the two members engaged with each other, and the durability of the friction engagement device may be reduced. Therefore, in the control method for the power transmission device according to the present embodiment, when resonance occurs, the engagement pressure of the friction engagement device is increased, and the upper limit torque of the torque limiter of the damper 51, that is, the limit torque. The torque capacity of the friction engagement device is increased.

  For example, when the first gear is set, the first clutch C1 and the third brake B3 are engaged. Therefore, in this case, the engagement pressure is increased by increasing the hydraulic pressure of at least one of the first clutch C1 and the third brake B3, and the torque capacity of the friction engagement device is increased. Is made larger than the limit torque of the torque limiter. Further, when the second gear is set, the first clutch C1 and the second brake B2 are engaged. Therefore, in this case, the engagement pressure is increased by increasing the hydraulic pressure of at least one of the first clutch C1 and the second brake B2, and the torque capacity of the friction engagement device is increased. Is made larger than the limit torque of the torque limiter.

  When the third gear is set, the first clutch C1 and the first brake B1 are engaged. Therefore, in this case, the engagement pressure is increased by increasing the hydraulic pressure of at least one of the first clutch C1 and the first brake B1, and the torque capacity of the friction engagement device is increased. Is made larger than the limit torque of the torque limiter. When the reverse gear is set, the second clutch C2 and the third brake B3 are engaged. Therefore, in this case, the engagement pressure is increased by increasing the hydraulic pressure of at least one of the second clutch C2 and the third brake B3, and the torque capacity of the friction engagement device is increased. Is made larger than the limit torque of the torque limiter.

  In this way, when resonance occurs, it is possible to suppress the occurrence of continuous slip between the two members engaged with each other in the friction engagement device, and to improve the durability of the friction engagement device. be able to. When resonance does not occur, the torque capacity of the friction engagement device is set to be equal to or less than the limit torque of the torque limiter. By doing in this way, a fuel consumption can be improved compared with the case where the torque capacity of a friction engagement device is always made larger than the limit torque of a torque limiter.

  Here, when the vehicle on which the power transmission device 10 is mounted is traveling on EV, an electric oil pump is used as a hydraulic pressure source of the friction engagement device. That is, during EV traveling, the engagement pressure of the friction engagement device is increased by increasing the hydraulic pressure of the electric oil pump.

  However, even when the value of the drive current supplied to the electric oil pump is increased to the rated value and the hydraulic pressure is increased, the engagement pressure is insufficient and the torque capacity of the friction engagement device becomes the limit torque of the torque limiter. May be: Therefore, in this case, in the friction engagement device, continuous slip may occur between the two members engaged with each other, and the durability of the friction engagement device may be reduced.

  Therefore, in the control method according to the present embodiment, in such a case, the value of the drive current supplied to the electric oil pump is rated for a predetermined time because the vibration due to resonance is expected to be temporary. By making it larger than the value, the hydraulic pressure of the electric oil pump is further increased. Here, the rated value is the maximum value of the drive current at which the electric oil pump can stably operate. By doing so, the insufficient engagement pressure can be compensated, and in the friction engagement device, it is possible to suppress the occurrence of continuous slip between the two members engaged with each other. Instead of doing this, the mechanical oil pump may be started to compensate for the insufficient engagement pressure. However, to start the mechanical oil pump using the crankshaft as the power source, the engine 8 is It needs to be started. In other words, EV driving continues when the value of the drive current supplied to the electric oil pump is larger than the rated value, rather than starting the mechanical oil pump to compensate for the insufficient engagement pressure. This is preferable because it can prevent a reduction in fuel consumption. However, if the vibration due to resonance does not stop after a predetermined time has elapsed, the engine 8 is started and the mechanical oil pump is started. In this way, even when the engagement pressure is insufficient even though the value of the drive current of the electric oil pump is larger than the rated value, the engagement pressure is reduced by starting the mechanical oil pump. In the friction engagement device, it is possible to suppress the occurrence of continuous slip between the two members engaged with each other.

  An example of the method for controlling the power transmission device according to the present embodiment will be described with reference to the time chart of FIG. In the time chart of FIG. 7, the time is plotted on the horizontal axis, the torque of the second electric motor M2, the electric oil pump (EOP) drive current, the limit torque of the torque limiter, the output torque, the engagement pressure of the mechanical transmission unit 20, the machine The vertical axis represents the transmission section hydraulic pressure, which is the hydraulic pressure of the friction engagement device in the automatic transmission section 20, the rotational speed of the first electric motor M1, and the vehicle speed.

  In FIG. 7, the time when resonance occurs is t1, and it is determined that resonance is occurring, that is, the time when resonance is detected is t2. As a method for detecting resonance, for example, a vehicle bench test is performed in advance to measure a driving state such as a vehicle speed at which resonance occurs, and the ECU 40 uses the measurement data based on the actual driving state. The resonance is detected. Note that the resonance may be detected directly from a change in torque or rotation speed.

  In the transmission section hydraulic pressure, the solid line indicates the hydraulic control when the resonance is detected, and the broken line indicates the hydraulic control when the resonance is not detected. Here, “Pb3” indicates the hydraulic pressure of the third brake B3, and “Pb2” indicates the hydraulic pressure of the second brake B2. As can be seen from the time chart of FIG. 6, the ECU 40 decreases the hydraulic pressure of the third brake B3 and increases the hydraulic pressure of the second brake B2 when resonance is not detected. That is, when the resonance is not detected, the ECU 40 switches from the first gear to the second gear by releasing the third brake B3 and engaging the second brake B2.

  On the other hand, when the resonance is detected, the ECU 40 prohibits shifting and raises the value of the EOP drive current, thereby raising the hydraulic pressure Pb3 of the third brake B3 and raising the engagement pressure. Here, since the speed change is prohibited, the vehicle speed remains constant. The reason for prohibiting the shift is to prevent a continuous slip in the friction engagement device due to a decrease in the engagement pressure during the shift, thereby reducing the durability of the friction engagement device.

  At time t3, the value of the EOP drive current is increased to the rated value, but because of insufficient engagement pressure, that is, the torque capacity of the friction engagement device is less than the limit torque of the torque limiter, vibration due to resonance. Is not suppressed. Therefore, the ECU 40 increases the hydraulic pressure Pb3 of the third brake B3 to increase the engagement pressure by increasing the value of the EOP drive current from the rated value for a predetermined time. By doing so, insufficient engagement pressure can be compensated, and in the friction engagement device, it is possible to suppress occurrence of continuous slip between two members engaged with each other. At time t4, since the torque capacity of the third brake B3 exceeds the limit torque of the torque limiter of the damper 51, vibration due to resonance is absorbed by the torque limiter. Therefore, after time t4, the ECU 40 maintains the engagement pressure of the third brake B3 as it is. At time t4, the ECU 40 determines that the resonance has subsided based on the operating state, so the engagement pressure is reduced by reducing the hydraulic pressure of the third brake B3.

  As described above, when resonance occurs, the frictional engagement device can suppress the occurrence of continuous slip between two members engaged with each other.

  Here, the predetermined time during which the value of the EOP drive current is made larger than the rated value is an adapted value determined in advance by experiments or the like. For example, in the time chart of FIG. 7, the predetermined time is set to a time from time t3 to time t6. If the ECU 40 determines that the vibration due to resonance does not stop at time t6, that is, the engagement pressure is insufficient, the ECU 8 starts the mechanical oil pump. . Even if the drive current value of the electric oil pump is larger than the rated value, even when the engagement pressure is insufficient and the vibration of the resonance cannot be settled, in this way, in the friction engagement device, It is possible to suppress the occurrence of continuous slip between the two members engaged with each other.

  Next, control processing of the power transmission device according to the above-described embodiment will be described with reference to the flowchart of FIG.

  First, in step S101, the ECU 40 detects whether resonance has occurred. For example, the ECU 40 detects resonance based on the actual driving state using measurement data obtained by measuring the driving state such as the vehicle speed at which resonance occurs. When the resonance is detected (step S101: Yes), the ECU 40 proceeds to the process of step S102. When the resonance is not detected (step S101: No), the ECU 40 returns this control process.

  In step S102, the ECU 40 prohibits shifting and controls the hydraulic control device 34 to increase the engagement pressure of the friction engagement device in the engaged state. Thereafter, the ECU 40 proceeds to the process of step S103.

  In step S103, when the value of the EOP drive current is increased to the rated value, the ECU 40 determines whether the engagement pressure is insufficient, that is, the torque capacity of the friction engagement device is equal to or less than the limit torque of the torque limiter. It is determined whether or not. Specifically, the ECU 40 determines whether vibration due to resonance has occurred based on the operating state. If the ECU 40 determines that vibration due to resonance is occurring, the ECU 40 determines that the engagement pressure is insufficient (step S103: Yes) and proceeds to the process of step S104. On the other hand, when determining that vibration due to resonance has not occurred, the ECU 40 determines that the engagement pressure is not insufficient (step S103: No), and ends the present control process.

  In step S104, the ECU 40 temporarily increases the engagement pressure of the friction engagement device by setting the value of the EOP drive current temporarily larger than the rated value. By doing in this way, the lack of engagement pressure can be compensated. Thereafter, the ECU 40 proceeds to the process of step S105.

  In step S105, the ECU 40 determines whether or not the engagement pressure is insufficient after a predetermined time has elapsed, specifically, whether or not vibration due to resonance has occurred based on the operating state. If the ECU 40 determines that vibration due to resonance has occurred, the ECU 40 determines that the engagement pressure is insufficient (step S105: Yes) and proceeds to the process of step S106. On the other hand, if the ECU 40 determines that vibration due to resonance has not occurred, the ECU 40 determines that the engagement pressure is not insufficient (step S105: No), and maintains the engagement pressure at this time until the vibration due to resonance has subsided. Return control processing.

  In step S106, the ECU 40 starts the engine 8 and starts the mechanical oil pump. Even if the drive current value of the electric oil pump is larger than the rated value, even when the engagement pressure is insufficient and the vibration of the resonance cannot be settled, in this way, in the friction engagement device, It is possible to suppress the occurrence of continuous slip between the two members engaged with each other. Thereafter, the ECU 40 returns this control process.

  As can be seen from the above description, in the driving method of the power transmission device according to the present embodiment, when resonance occurs during EV traveling, the ECU 40 controls the driving current of the electric oil pump to control the damper 51. The torque capacity of the friction engagement device is made larger than the limit torque of the torque limiter. Here, the ECU 40 raises the engagement pressure of the friction engagement device by temporarily setting the value of the drive current to be larger than the rated value. By doing so, it is possible to compensate for a lack of engagement pressure when the torque capacity of the friction engagement device is made larger than the upper limit torque of the torque limiter. Thereby, in a friction engagement device, generation | occurrence | production of the continuous slip between two members mutually engaged can be suppressed, and durability of the said friction engagement device can be improved.

  In addition, this invention is not limited to the above-mentioned embodiment, It can implement with a various form within the range of the summary of this invention. For example, in the above-described embodiment, the example in which the present invention is applied to the power transmission device including the friction engagement device has been described. However, the power transmission device to which the present invention can be applied is not limited thereto. Instead of doing this, the present invention can also be applied to a power transmission device provided with other clamping means other than a friction engagement device such as a pulley. That is, by controlling the drive current of the electric oil pump to increase the clamping pressure of the clamping means and make the torque capacity of the clamping means larger than the limit torque of the torque limiter, Similar effects can be obtained.

8 Engine 10 Power transmission device 11 Continuously variable transmission unit 20 Mechanical transmission unit 51 Damper 34 with torque limiter Hydraulic control device 40 ECU
M1, M2 Electric motors C1, C2, B1, B2, B3 Friction engagement device

Claims (2)

A control device for a power transmission device applied to a power transmission device for transmitting power output from a power source, comprising a clamping means and an electric oil pump as a hydraulic source of the clamping means,
Control means for increasing the clamping pressure of the clamping means during resonance,
The control device of the power transmission device, wherein the control means makes a value of a drive current of the electric oil pump larger than a rated value for a predetermined time. The power transmission device includes a mechanical oil pump that uses an engine and an electric motor as the power source, and changes oil pressure in accordance with the rotational speed of the engine,
The control device for a power transmission device according to claim 1, wherein the control means starts the mechanical oil pump by starting the engine.

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