JP6531639B2 - Friction engagement device - Google Patents

Description

  The present invention relates to a friction engagement device used, for example, in an automatic transmission of a vehicle, and more particularly to a friction engagement device that supplies lubricating oil to a plurality of friction members.

  2. Description of the Related Art A friction engagement device used in, for example, an automatic transmission of a vehicle is known. The friction engagement device comprises a plurality of inner plates and a plurality of outer plates disposed between the respective inner plates. The plurality of inner plates and the plurality of outer plates constitute a friction member, and are pushed in one direction by advancing and retracting the piston to be in an engaged state where they engage with each other and in a released state where the engagement is released. The state changes. During transition to these states, the friction members slip engage with each other. Lubricating oil is supplied to prevent seizing due to slip engagement. By the way, in the friction engagement device, when the lubricating oil is supplied in the released state, a drag loss may occur due to the lubricating oil. For example, when the friction engagement device is in the released state, the lubricating oil is sheared by the rotational speed difference of the friction member. For this reason, if the amount of lubricating oil is large, the drag loss becomes large, and the efficiency of the friction engagement device is reduced.

  Therefore, a wet multi-plate clutch is known which is configured to prevent the drag loss occurring in the released state (see, for example, Patent Document 1). In the wet multi-disc clutch, when the outer plate and the inner plate are frictionally engaged due to the pressing of the piston rather than the released state in which the outer plate and the inner plate are separated from each other, the slide oil hole and the inner hole It is comprised so that the distribution resistance of lubricating oil between oil holes may become small. According to this, in the engaged state, the flow resistance between the slide oil passing hole and the inner oil passing hole is reduced, so that the supply amount of the lubricating oil to the joint portion can be increased. The frictional heat in the part can be sufficiently dissipated, and the plate can be prevented from burning. Further, in the released state, the flow resistance of the lubricating oil between the slide oil passing hole and the inner oil passing hole is increased, so that the amount of lubricating oil supplied between the inner plate and the outer plate can be suppressed. it can.

  As another friction engagement device, for example, a return spring for returning the piston from the pressing position to the original position is constituted by two springs, and the reaction force to the pressing force of the piston by the two springs is It is known that the response of the engagement of the friction member and the reduction of the drag loss are compatible with each other by acting on different sections (see, for example, Patent Document 2).

JP, 2013-190053, A JP, 2008-215503, A

  However, in the above-described wet multi-plate clutch, the supply of lubricating oil is gradually reduced as the state changes from the engaged state to the released state. Therefore, compared with a wet multi-plate which constantly supplies lubricating oil, the supply of lubricating oil in the released state is smaller than that in the engaged state, so that the drag loss can be reduced. However, in the open state, the supply of lubricating oil is reduced, including the previous transition, so under the condition where the calorific value is large, the cooling performance may be insufficient and the temperature of the friction member may increase. is there.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above technical problems, and an object of the present invention is to provide a friction engagement device which achieves both reduction in drag loss and improvement in cooling performance of a friction member.

In order to achieve the above object, the present invention is arranged in a pressing member disposed movably in one direction inside a case, and a storage chamber partitioned in the inside of the case. A friction engagement device comprising: a first friction member and a second friction member whose state changes between an engagement state in which the movement is engaged and a release state in which the engagement is released; Controlling movement of the pressing member to each of an engagement position to be changed to the combined state, a release position to be changed to the release state, and an intermediate position set between the engagement position and the release position The control unit moves in conjunction with the pressing member, and when the pressing member moves to the release position, moves to a closed position closing an oil passage for supplying lubricating oil to the storage chamber, Member in the intermediate position When you dynamic example Bei the opening and closing member to move to the open position opening the fluid passage, wherein, when the first friction member and the second friction member to the released state, the first friction The cooling time for supplying the lubricating oil to the storage chamber is set based on the calorific value of the member or the second friction member, the pressing member is moved to the intermediate position, and the pressing is performed during the cooling time. the position of the member is maintained in the intermediate position, after the cooling time has elapsed and is characterized that you move the press member from said intermediate position to said release position.

  According to the present invention, when the piston is moved to the release position, the opening and closing member is moved to the closed position closing the oil passage. When the piston is moved to the intermediate position set between the engagement position and the release position, the opening and closing member is moved to the open position that opens the oil passage. Therefore, as compared with a friction engagement device that constantly supplies lubricating oil, it is possible to stop the supply of lubricating oil in the release state, so that drag loss can be reduced. In addition to this, the opening / closing member opens the oil passage at, for example, an intermediate position during transition from the engaged position to the released state, so that heat generated by, for example, slip engagement can be cooled quickly by the supply of lubricating oil. be able to. By this, it is possible to prevent the temperature of the friction member from rising due to the insufficient cooling performance even under the condition where the calorific value of the friction member becomes large.

It is an explanatory view showing roughly an example of vehicles to which this invention is applied. It is a skeleton figure which shows the automatic transmission of the vehicle shown in FIG. It is a figure which shows the engagement table of the automatic transmission shown in FIG. FIG. 5 is a cross-sectional view showing a second brake mechanism of the automatic transmission shown in FIG. 2; It is explanatory drawing which shows the piston of the 2nd brake mechanism shown in FIG. It is a figure which shows the relationship of the opening / closing state of an opening-and-closing member, and the state of a 2nd brake mechanism with respect to the position of a piston. It is a flowchart which shows the procedure of the operation | movement which releases a 2nd brake mechanism. It is a time chart which shows operation of engagement or release of the 2nd brake mechanism.

  FIG. 1 is an explanatory view showing an example of a vehicle applied to the present invention. As shown in FIG. 1, the vehicle 10 is a FF (Front engine, Front drive) type vehicle. The present invention is not limited to the FF type vehicle, and may be, for example, a FR (Front engine, Rear drive) type vehicle. The vehicle 10 includes an internal combustion engine 11, an automatic transmission 12, a differential 15, a drive shaft 16, drive wheels 17 and an ECU (Electronic Control Unit) 18.

  The internal combustion engine 11 burns fuel internally to output a driving force, and is, for example, an engine. Hereinafter, the internal combustion engine 11 will be described as an engine. The driving force output from the engine 11 is transmitted to the automatic transmission 12. The automatic transmission 12 is provided with a torque converter 19 and a transmission 20, and sets the gear of the transmission 20 to a target gear according to the driving condition of the vehicle 10, for example, information of vehicle speed and engine load (accelerator opening). change. The torque converter 19 internally includes a working fluid, and transmits the driving force output from the engine 11 to the transmission 20 via the working fluid. The transmission 20 includes a plurality of shift speeds, and increases or decreases the input drive power to a predetermined drive power and transmits the drive power to the differential 15 by setting the target shift speed. The differential 15 transmits a driving force to drive wheels 17 attached to the left and right of the drive shaft 16.

  The ECU 18 includes, for example, vehicle speed information sent from a vehicle speed sensor 22 for detecting the rotational speed of the drive shaft 16, position information sent from a position switch 24 provided on the shift lever 23, and an accelerator opening degree sensor provided on an accelerator pedal 25. The accelerator opening information sent by the H.26 is input. The ECU 18 is also provided with the brake information sent by the stroke sensor 28 provided at the brake pedal 27, the throttle opening information sent by the throttle opening degree sensor 29 provided at the electronic throttle valve 33 of the engine 11, and the engine 11. The engine speed information sent from the engine speed sensor 30 is input. Further, the input shaft rotational speed information transmitted by the input shaft rotational speed sensor 31 provided in the automatic transmission 12 and the output shaft rotational speed information transmitted by the output shaft rotational speed sensor 32 are input to the ECU 18. A manual mode may be provided in which the gear position of the transmission 20 is set to the gear position selected by the driver. The ECU 18 processes the input information on the basis of a map and a program stored in the ROM (Read Only Memory) 34, and based on the result obtained, the vehicle 10 is brought into the optimum driving state. , The engine 11 and the automatic transmission 12 are controlled.

  FIG. 2 is a skeleton diagram showing an example of the automatic transmission 12. As shown in FIG. 2, the automatic transmission 12 includes a torque converter 19 and a transmission 20. The torque converter 19 includes an input shaft 35 to which a driving force input from the engine 11 is transmitted, and an output shaft 36 that outputs the transmission 20. As the transmission 20, for example, a planetary gear unit is used. The planetary gear unit includes a first planetary gear mechanism 37, a second planetary gear mechanism 38, an output gear 39, a first brake mechanism 40, a second brake mechanism 41 and a third brake mechanism 42, a first clutch mechanism 43 and a second clutch mechanism It has 44. Note that at least one of the first clutch mechanism 43, the second clutch mechanism 44, the first brake mechanism 40, the second brake mechanism 41, and the third brake mechanism 42 is an example of a friction engagement device.

  The first planetary gear mechanism 37 is a single pinion type planetary gear mechanism, and includes a sun gear 45, a pinion gear 46, a ring gear 47 and a carrier 48. The sun gear 45 is connected to the output shaft 36 of the torque converter 19. The pinion gear 46 is rotatably supported by the carrier 48 and meshes with the sun gear 45 and the ring gear 47, respectively. The third brake mechanism 42 fixes the ring gear 47 to the case 49 of the automatic transmission 12. The first brake mechanism 40 fixes the carrier 48 to the case 49.

  The second planetary gear mechanism 38 is a Ravigneaux type planetary gear mechanism, and includes a sun gear 50, a short pinion gear 51, a carrier 52, a long pinion gear 53, a carrier 54, a sun gear 55, and a ring gear 56. The sun gear 50 is connected to the carrier 48 of the first planetary gear mechanism 37. The short pinion gear 51 is rotatably supported by the carrier 52. The short pinion gear 51 meshes with the sun gear 50 and the long pinion gear 53. The carrier 52 is connected to the output gear 39. The long pinion gear 53 is rotatably supported by the carrier 54, and meshes with the short pinion gear 51, the sun gear 55, and the ring gear 56, respectively. The carrier 54 is coupled to the output gear 39. The first clutch mechanism 43 engages the sun gear 55 with the output shaft 36 of the torque converter 19. The second brake mechanism 41 fixes the ring gear 56 to the case 49. The second clutch mechanism 44 engages the ring gear 56 and the output shaft 36.

  The ECU 18 transmits control signals to various solenoid valves provided in the hydraulic pressure controller 58 to transmit the control signals to the first clutch mechanism 43, the second clutch mechanism 44, the first brake mechanism 40, the second brake mechanism 41, and the third brake mechanism 42. The hydraulic pressure supplied is controlled respectively. Specifically, the oil pressure controller 58 is provided with an oil pump 60 connected to a crankshaft (not shown) of the engine 11. The oil pump 60 is driven by rotation of a crankshaft (not shown) to generate oil pressure by the supply of hydraulic oil and lubricating oil. The hydraulic pressure generated by the oil pump 60 is supplied to various solenoid valves (not shown). The various solenoid valves (not shown) are duty-controlled based on control signals from the ECU 18. The lubricating oil is used to cool the friction member described later in detail. The hydraulic oil and the lubricating oil may be the same or similar.

  The first clutch mechanism 43, the second clutch mechanism 44, the first brake mechanism 40, the second brake mechanism 41, and the third brake mechanism 42 are each formed of a multi-plate friction engagement device. The first clutch mechanism 43 and the second clutch mechanism 44 have, for example, a plurality of first friction plates (not shown) on the input side to which the driving force is input, and a plurality of second friction mechanisms, for example, the plurality of second friction plates And a friction plate (not shown). The engagement force of the first friction plate (not shown) and the second friction plate (not shown) is controlled by the hydraulic pressure of the hydraulic oil supplied by the oil pump 60.

  Each of the first brake mechanism 40, the second brake mechanism 41, and the third brake mechanism 42 is constituted by a multi-plate type friction engagement device. Each of the brake mechanisms 40 to 42 is, for example, a plurality of outer plates (not shown) spline-fitted to the inner surface of the case 49 and a plurality of inner members, for example, inner splines. And a plate (not shown). The engagement force between the outer plate (not shown) and the inner plate (not shown) is controlled by the hydraulic pressure of the hydraulic fluid. The engagement pressure of the first clutch mechanism 43, the second clutch mechanism 44, the first brake mechanism 40, the second brake mechanism 41, and the third brake mechanism 42 is not limited to oil pressure, and may be controlled using, for example, air pressure. Alternatively, instead of the multi-plate friction engagement device, a single-plate friction engagement device may be used.

  FIG. 3 shows an engagement table for explaining the states of the brake mechanism and the clutch mechanism for establishing each shift speed of the automatic transmission described in FIG. The automatic transmission 12 can be set to seven shift speeds, that is, first to sixth speeds of forward gear and reverse gear. In FIG. 3, among the shift speeds, the first gear in forward gear is "1ST", the second gear in forward gear is "2ND", the third gear in forward gear is "3RD", and the fourth gear in forward gear is "4TH", The fifth gear of the gear is indicated as "5TH", the sixth gear of forward gear as "6TH" and the reverse gear as "REV". Further, in FIG. 3, the first clutch mechanism 43 is “C1”, the second clutch mechanism 44 is “C2”, the first brake mechanism 40 is “B1”, and the second brake mechanism 41 is “B2” and the third brake mechanism. 42 is represented as "B3". Furthermore, as the states of the first clutch mechanism 43, the second clutch mechanism 44, the first brake mechanism 40, the second brake mechanism 41, and the third brake mechanism 42 at each gear, "o" is engaged or fixed, "X" represents as release.

  As shown in FIG. 3, the first clutch mechanism 43 is engaged in all the first to fourth gear stages. That is, the first clutch mechanism 43 is an input clutch in the first gear to the fourth gear. The second clutch mechanism 44 is engaged at fourth to sixth speeds. The first brake mechanism 40 is engaged at the second and sixth speeds. The second brake mechanism 41 is engaged in the first gear and the reverse gear. The third brake mechanism 42 is engaged at the third gear, the fifth gear and the reverse gear.

  Here, for example, the friction engagement device according to the present invention can be applied to any of the first clutch mechanism 43, the second clutch mechanism 44, the first brake mechanism 40, the second brake mechanism 41, and the third brake mechanism 42 described above. For example, the number of application of the friction engagement device of the present invention is not limited. Hereinafter, an example in which the friction engagement device of the present invention is applied to the second brake mechanism 41 will be described.

  FIG. 4 is a cross-sectional view showing the main part of the second brake mechanism 41 in the transmission. As shown in FIG. 4, the case 49 is fixed to the vehicle 10, and the components constituting the transmission 20 are accommodated in a watertight manner inside. The second brake mechanism 41 includes a plurality of outer plates 62 fixed to the inner wall of the case 49, and a plurality of inner plates 63 spline-fitted to a ring gear 56 constituting the transmission 20. A plurality of inner plates 63 are arranged in series in the axial direction, and are inserted between each of the outer plates 62. The outer plate 62 is an example of a first friction member, and the inner plate 63 is an example of a second friction member.

  The outer plate 62 and the inner plate 63 are housed in a housing chamber 65 divided by a case 49, a ring gear 56 and a piston 64. The storage chamber 65 is annularly provided in the case 49. The piston 64 is axially movably disposed in a recess 66 provided in the inner right wall of the case 49. An oil seal 61 is attached to the piston 64 in order to create a watertight space with the recess 66. The recess 66 functions as an oil chamber that generates a pressing force on the piston 64. The piston 64 engages the outer plate 62 and the inner plate 63 by a pressing force. A flange 59 is disposed on the opposite side of the piston 64 with the plurality of outer plates 62 and the plurality of inner plates 63 interposed therebetween. The flange 59 acts to receive the pressure of the piston 64. The piston 64 is an example of a pressing member. In the second brake mechanism 41, when the hydraulic oil is supplied from the hydraulic controller 58 to the recess 66, the piston 64 moves in the pressing direction, and the plurality of outer plates 62 and the plurality of inners are interposed between the piston 64 and the flange 59. The plate 63 is pinched to be in an engaged state.

  The ring gear 56 is provided with a first hole 67 for guiding the lubricating oil 73 to the storage chamber 65. The first hole 67 is formed to be long in the axial direction, for example, in a slit shape in cross section. A plurality of first holes 67 having a slit shape in cross section are formed at predetermined intervals along the circumferential direction of the ring gear 56. As the first hole 67, a plurality of circular holes in cross section may be arranged in the axial direction instead of the slit-like long holes. The portion where the first hole 67 is formed is a first arm portion 68 which extends in a substantially arm-like cross section from the left to the right in FIG. A plurality of inner plates 63 are fixed to the first arm 68 at predetermined intervals. The first hole 67 is a through hole for supplying lubricating oil 73 from the inner diameter side of the first arm 68 to the storage chamber 65 between the inner plates 63 of any of the plurality of inner plates 63 and It has become. The hydraulic pressure control unit 72 is controlled by the ECU 18 to control the hydraulic pressure of the lubricating oil 73 supplied from the oil pump 60 toward the storage chamber 65 via the inside of the case 49. For example, when supplying the lubricating oil 73 to the storage chamber 65, the hydraulic control unit 72 performs control to increase the lubricating amount of the lubricating oil 73. The first hole 67 is an example of an oil passage.

  On the other hand, in the piston 64, a second hole 69 is formed, for example, in a circular shape in cross section. The second hole 69 is provided on the tip of the second arm 70 which extends in a substantially arm-like shape in cross section from the right to the left in FIG. The second arm 70 is integrally provided to the piston 64, and a plurality of second holes 69 are formed in the second arm 70 at predetermined intervals in the circumferential direction of the piston 64. When the piston 64 moves to the intermediate position and the engagement position, the second arm 70 moves the second hole 69 below the first hole 67 to move the first hole 67 to the open position. Further, in the second arm portion 70, the shielding portion 71 provided on the rear side in the pressing direction of the piston 64 with respect to the second hole 69 under the first hole 67 when the piston 64 moves to the release position. It moves to the closed position where the first hole 67 is closed by the shielding part 71. The second arm 70 including the shielding part 71 and the second hole 69 may be divided into members different from the piston 64. In this case, the divided second arm 70 may be configured to move in conjunction with the movement of the piston 64. The second arm 70 including the second hole 69 and the shielding portion 71 is an example of the opening and closing member.

  FIG. 5 is an explanatory view schematically showing the configuration of the piston 64. As shown in FIG. The piston 64 is axially movably disposed by the hydraulic pressure supplied from the hydraulic pressure controller 58. The ECU 18 is, for example, a release position at which the piston 64 is proximal to the recess 66 in the axial direction according to a gear change factor and a heat generation factor of the rotating element to be fixed, an engagement position at the distal end, and a release position. Control is performed to move each to an intermediate position set between the position and the engagement position. When the piston 64 is in the release position, the second brake mechanism 41 changes to the release state in which the engagement between the outer plate 62 and the inner plate 63 is released. When the piston 64 is in the engagement position, the second brake mechanism 41 changes to an engagement state in which the outer plate 62 and the inner plate 63 are engaged. The intermediate position is set to have a predetermined width in the axial direction. For example, the intermediate position is a state prior to the state in which the outer plate 62 and the inner plate 63 completely engage in the engaged state (hereinafter referred to as "completely engaged state"), for example, slip engaged. From the change position, it is set in the range including the position to change to the release state. The change to the release state does not change only when the piston 64 moves to the release position, but changes when moving within the range from the release position to a predetermined position closer to the engagement position. Therefore, the ECU 18 moves the piston 64 to any one of the intermediate positions by controlling the engagement pressure, whereby the second brake mechanism 41 is in a predetermined state between the release state and the slip engagement state. It can be set to The ECU 18 and the hydraulic pressure controller 58 are an example of a control unit.

  The ECU 18 executes arithmetic processing based on various control programs and maps stored in the ROM 34. The RAM 74 is a memory for temporarily storing the calculation result in the ECU 18, data input from each sensor, and the like. By operating based on the control program stored in the ROM 34, the ECU 18 functions as, for example, an information collection unit 75, a shift speed determination unit 76, a calculation unit 77, and a counter 78.

  The information collection unit 75 sequentially collects each information of the vehicle 10. The shift speed determination unit 76 calculates the vehicle speed on the basis of, for example, the output signal of the output shaft rotational speed sensor 32, and calculates the throttle opening based on the output signal of the throttle opening sensor 29. Then, based on the calculated vehicle speed and throttle opening degree, the shift stage determination unit 76 selects a target shift stage with reference to, for example, the shift map stored in the ROM 34, and selects the target shift stage and the current shift stage. To determine whether a shift is necessary. The calculation unit 77 calculates, for example, the calorific value of the inner plate 63 when it is determined that the shift is necessary and the second brake mechanism 41 is changed from the engaged state to the released state. For example, the amount of heat generation of the inner plate 63 is calculated based on the amount of rotation of the ring gear 56, the change in torque, or the hydraulic pressure of the hydraulic oil supplied from the hydraulic controller 58. The calculation unit 77 calculates, for example, the temperature of the inner plate 63 based on the calculated calorific value, and calculates, for example, a cooling time for cooling the inner plate 63 based on the calculated temperature. The cooling time corresponds to the time for supplying the lubricating oil 73. The time for supplying the lubricating oil 73 corresponds to the time for keeping the piston 64 at the intermediate position. The counter 78 is for counting the time for keeping the piston 64 in the middle position. Note that, instead of the inner plate 63, the amount of heat generation and the temperature with respect to the outer plate 62 may be calculated to determine the time for maintaining the intermediate position.

  In the piston 64, the ECU 18 controls the position of the piston 64 with high precision by utilizing the reaction force from the return spring in addition to the control of the hydraulic pressure. The return spring includes a first spring 80, a second spring 81 and a third spring 82. The first spring 80 generates a reaction force against the pressing force acting on the piston 64 by the supply of the hydraulic pressure in a section in which the piston 64 is moved from the engagement position to the release position. The second spring 81 and the third spring 82 are respectively disposed on both sides sandwiching the first spring 80, and generate the reaction force in a section in which the piston 64 is moved from the engaged position to the intermediate position. Between the release position and the intermediate position, the reaction force acting on the piston 64 is smaller than that between the engaged position and the intermediate position. For this reason, it is possible to accurately control the position of the piston 64 between the release position and the intermediate position. The second and third springs may be the same or similar.

  The ECU 18 reduces the oil pressure of the lubricating oil supplied to the recess 66 and returns the piston 64 to the release position. In this case, in the section in which the piston 64 moves from the engaged position to the intermediate position, it is returned to the release position by the biasing force of the first spring 80, the second spring 81 and the third spring 82. Further, in the section in which the piston 64 moves from the intermediate position to the release position, it is returned to the release position by the biasing force of the first spring 80.

  FIG. 6 is a view showing the relationship between the open / close state of the open / close member and the state of the second brake mechanism 41 with respect to the position of the piston 64. As shown in FIG. “B2” shown in FIG. 6 represents the second brake mechanism 41. When the piston 64 is moved to the engaged position, the second arm 70 is moved to the open position where the first hole 67 is opened by the second hole 69. At this time, the second brake mechanism 41 is fully engaged. When the piston 64 moves to the intermediate position, the second arm 70 is moved to the open position where the first hole 67 is opened by the second hole 69. The first hole 67 is formed in the shape of an elongated slit in the axial direction. Therefore, while the piston 64 moves from the engaged position to the intermediate position, the second arm 70 can be maintained in the open position. When the piston 64 is at the intermediate position, the second brake mechanism 41 is in the slip engagement or release state. When the piston 64 moves to the release position, the second arm 70 is moved to the closed position where the shield 71 shields the first hole 67. At this time, the second brake mechanism 41 is in the released state.

  FIG. 7 is a flowchart showing the procedure of the operation of releasing the second brake mechanism 41. As shown in FIG. 7, in step S1, the information collecting unit 75 sets each information of the vehicle 10, for example, the hydraulic pressure supplied to each unit by the hydraulic controller 58 and the rotational speed information of each rotating element of the engine 11 and the automatic transmission 12. Collect sequentially. In step S2, it is determined whether the shift request requires the second brake mechanism 41 to switch from the engaged state to the released state. For example, the ECU 18 compares the target shift position at that time with the current shift position according to the driving condition of the vehicle 10, and outputs a shift request when it is necessary to shift. It is determined whether the second brake mechanism 41 in the shift request needs to be changed from the engaged state to the released state. If the determination in step S2 is affirmative (in the case of the Y side), the process proceeds to step S3. In step S3, the calculation unit 77 calculates, for example, the calorific value of the inner plate 63 based on, for example, the rotation amount of the ring gear 56, the torque change, or the hydraulic pressure (engagement pressure) to the piston 64 up to that point. . In step S4, the calculation unit 77 calculates, for example, the temperature of the inner plate 63 based on the calorific value. The temperature may be calculated or estimated from the calorific value using, for example, the temperature of the lubricating oil 73, the use condition of the second brake mechanism 41 until then, and the atmospheric temperature.

  In step S5, the supply time (t0) of the lubricating oil 73 is calculated based on the calculated temperature. In this case, for example, the correspondence between the temperature of the inner plate 63 and the supply time of the lubricating oil 73 may be calculated based on a previously recorded map. In step S6, for example, the piston 64 is moved from the engaged position to the intermediate position. In step S7, the counter 78 counts time on the basis of the time when the command to move to the intermediate position is output. In step S8, it is determined whether the count value (t) measured by the counter 78 has exceeded the cooling time (t0). If the determination is affirmative (in the case of the Y side), the process proceeds to step S9. In step S9, control is performed to move the piston 64 from the intermediate position to the release position. If the result is negative at step S2 (in the case of the N side), the process is shifted to return. In addition, if the result of step S8 is negative (in the case of the N side), clocking in step S7 is continued. A temperature sensor may be provided to detect the temperature of the inner plate 63 directly or indirectly. In this case, the calculation of the calorific value described in step S3 and the calculation of the temperature described in step S4 can be omitted.

  FIG. 8 is a time chart showing an example in which the second brake mechanism 41 operates while the vehicle 10 is traveling. Note that “B2” shown in FIG. 8 represents the second brake mechanism 41. At time t1, the automatic transmission 12 shifts up the transmission gear position from the first gear position to the second gear position (symbol A shown in the figure). In this case, oil pressure control on the release side for changing the second brake mechanism 41 from the engaged state to the released state is performed. When hydraulic control on the release side (symbol B shown in the same figure) is performed, torque fluctuation is much less than that on the hydraulic control on the engagement side (symbol C shown in the figure) that changes from the released state to the engaged state. Since it is not necessary to take into consideration, hydraulic control is performed to quickly reduce the engagement force. At this time, for example, the actual temperature of the inner plate 63 is a symbol D shown in the figure. The actual temperature D is estimated based on, for example, the rotation speed and torque of the inner plate 63 at that time, and the time F for keeping the piston 64 at the intermediate position based on the estimated temperature, that is, the cooling time "t0" is calculated Desired. During the cooling time "t0", the hydraulic control unit 72 carries out control to increase the lubricating amount of the lubricating oil 73. For this reason, the amount of lubricating oil 73 (symbol G shown in the same figure) supplied to the storage chamber 65 is larger than the amount of lubricant (code H shown in the same figure) at the previous engagement position. . Thus, when the piston 64 is at the intermediate position, the second hole 69 opens the first hole 67, so the lubricating oil 73 is supplied toward the storage chamber 65. Therefore, it is possible to rapidly cool the frictional heat generated while the second brake mechanism 41 shifts from the engaged state to the released state (symbol D1 shown in the same drawing).

  At time t2, the piston 64 is moved from the intermediate position to the release position. The shielding portion 71 closes the first hole 67 by moving the piston 64 to the release position. The hydraulic control unit 72 performs control to reduce the amount of lubricating oil 73 (symbol K shown in the figure). In the second brake mechanism 41, since the lubricating oil 73 has been supplied to the storage chamber 65 until just before, for example, the inner plate 63 is cooled in advance. For this reason, it is possible to significantly reduce the time for natural cooling after the change to the release state (symbol D2 shown in the same drawing). The control to reduce the amount of lubrication includes the fact that the supply of the lubricating oil 73 to the storage chamber 65 becomes zero.

  At time t3, the automatic transmission 12 is downshifted from the second gear to the first gear (symbol H shown in the figure). In this case, hydraulic control on the engagement side (code C shown in the same figure) for changing the second brake mechanism 41 from the released state to the engaged state is performed. In this case, hydraulic control is performed to cause engagement to be performed more quickly than control on the release side (symbol B shown in the same drawing). Therefore, in the hydraulic control on the engagement side, control for maintaining the piston 64 at the intermediate position is not performed. While the piston 64 is moving to the engagement position (symbol I shown in the figure), the hydraulic control unit 72 carries out control to increase the lubricating amount of the lubricating oil 73 (symbol J shown in the figure). When the piston 64 is in the engaged position, the second hole 69 opens the first hole 67. However, since the outer plate 62 and the inner plate 63 are completely engaged and fixed to each other, there is no problem if the lubricating oil 73 is supplied to the storage chamber 65. In the case of the clutch mechanism, since the friction members are completely engaged with each other and integrally rotate, no slippage occurs even when the lubricating oil 73 gets in between the friction members.

  In the case of this embodiment, the supply of the lubricating oil 73 to the storage chamber 65 is stopped or reduced as indicated by symbol K in the same figure in the released state. Therefore, compared to the example where the lubricating oil 73 is constantly supplied to the storage chamber 65 (symbol M shown by a dotted line in the figure), the amount of work loss due to the resistance of the rotating inner plate 63 by the lubricating oil 73 ( The symbol N) shown by a dotted line in the same figure can be greatly reduced.

  As mentioned above, although demonstrated based on the Example, this invention is not limited to the Example mentioned above, A various change is added and implemented within the range which does not deviate from the meaning. For example, although the opening-closing member of this invention is comprised by the 1st hole 67, the 2nd hole 69, and the shielding part 71, it does not restrict to these structures by this invention.

  Further, although an example in which the present invention is applied to the second brake mechanism 41 having the configuration of the automatic transmission 12 has been described, any one of the other brake mechanisms 40 and 42 and the respective clutch mechanisms 43 and 44 or each brake It goes without saying that the present invention is also applicable to any combination of the mechanisms 40 and 42 and the clutch mechanisms 43 and 44. Also, instead of the first spring 80, the second spring 81 and the third spring 82 constituting the return spring, for example, an elastic body may be provided between the plurality of outer plates 62 and the plurality of inner plates 63. In this case, the space between the outer plate 62 and the inner plate 63 may be biased to a predetermined distance by the elastic body. Furthermore, the return spring and the elastic body may be omitted as long as the piston 64 can be quickly returned to the release position.

  12: Automatic transmission, 18: ECU, 41: Second brake mechanism, 58: Hydraulic controller, 62: Outer plate, 63: Inner plate, 64: Piston, 65: Storage chamber, 66: Recess, 67: First hole 69: second hole 71: shielding part 73: lubricating oil.

Claims (1)

The pressing member is disposed in the inside of the case so as to be movable in one direction, and the receiving chamber is disposed in the inside of the case, and the engaging state in which the pressing members are engaged with each other by the movement of the pressing members. In a friction engagement device comprising a first friction member and a second friction member whose state changes between a release state where the coupling is released.
The movement of the pressing member to each of the engagement position for changing to the engagement state, the release position for changing to the release state, and the intermediate position set between the engagement position and the release position A control unit to control
While moving in conjunction with the pressing member, when the pressing member moves to the release position, the pressing member moves to a closing position for closing an oil passage for supplying lubricating oil to the storage chamber, and the pressing member is moved to the middle when moved to the position e Bei the opening and closing member to move to the open position opening the fluid passage,
The control unit
When the first friction member and the second friction member are in the released state,
The cooling time for supplying the lubricating oil to the storage chamber is set based on the calorific value of the first friction member or the second friction member,
Moving the pressing member to the intermediate position, and maintaining the position of the pressing member at the intermediate position during the cooling time,
Moving the pressing member from the intermediate position to the release position after the cooling time has elapsed
Friction engagement device which is characterized a call.

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