JP5187246B2 - Power transmission device - Google Patents

Description

  The present invention relates to a power transmission device that is mounted on a vehicle and includes a clutch that transmits power from a prime mover to an axle.

  Conventionally, this type of power transmission device includes a hydraulic pump that is driven by power from an engine, a manual shift valve that is linked to a shift operation, and a solenoid valve that has an input port connected to the hydraulic pump via a manual shift valve. A second position that is interposed in an oil passage connecting the output port of the solenoid valve and the friction engagement device (clutch) and that blocks the oil passage (including a built-in check valve). There is proposed a hydraulic circuit that includes a selection valve configured as a two-position electromagnetic valve that selects a position and an electromagnetic pump that directly supplies a discharge pressure to the clutch (for example, Patent Document 1). reference).

JP 2008-180303 A

  In a power transmission device equipped with such a hydraulic circuit, when a shift operation is performed from the drive (D) position to the neutral (N) position while the clutch is engaged, the clutch is supplied to release the clutch. It is necessary to drain the hydraulic fluid. In this case, in order to obtain a good shift feel, it is desirable to appropriately control the drain pressure as much as possible.

  The power transmission device of the present invention is mainly intended to realize a good shift feel when the clutch is engaged and the clutch is disengaged by shifting from the forward position to the neutral position. .

  The power transmission device of the present invention employs the following means in order to achieve the main object described above.

The power transmission device of the present invention is
A power transmission device including a clutch mounted on a vehicle and transmitting power from a prime mover to an axle,
A first pump that generates fluid pressure by power from the prime mover;
A manual valve for switching whether to supply the fluid pressure from the first pump to the clutch according to a shift operation, and for draining the working fluid supplied to the clutch when the shift operation is performed to a neutral position; ,
A second pump for generating fluid pressure by operating upon receiving power supply and supplying the fluid to the clutch;
And a neutral position control means for controlling the second pump so as to be driven on the condition that a shift operation from the forward position to the neutral position is performed.

  In the power transmission device according to the present invention, whether to supply the fluid pressure from the first pump to the clutch according to the shift operation is switched, and when the shift operation is performed to the neutral position, the working fluid supplied to the clutch is supplied. A manual valve that drains and a second pump that operates by receiving electric power to generate fluid pressure and supplies the fluid to the clutch, and the neutral position from the forward position with the clutch engaged The second pump is driven so as to be driven on condition that the shift operation is performed. As a result, the working fluid supplied to the clutch can be gradually drained when the clutch is disengaged by shifting from the forward position to the neutral position, so that a good shift feel can be realized. it can. Here, the “prime mover” includes an internal combustion engine capable of automatic stop and automatic start, and also includes an electric motor capable of outputting driving power. The “clutch” includes a normal clutch that connects two rotating systems, and also includes a brake that connects one rotating system to a stationary system such as a case. Furthermore, the "second pump" includes a normal electric pump that generates fluid pressure by being driven by power from an electric motor, and fluid pressure that is generated by reciprocating a movable portion by electromagnetic force and spring biasing force. Includes electromagnetic pumps to be generated.

  In such a power transmission device of the present invention, the power transmission device includes a linear solenoid valve that regulates the fluid pressure from the manual valve and supplies the pressure to the clutch, and the neutral position control means performs a shift operation from the forward position to the neutral position. On this condition, the second pump and the linear solenoid valve may be controlled so that the fluid pressure acting on the clutch is gradually reduced. In this aspect of the power transmission device according to the present invention, the manual valve includes an input port for inputting a fluid pressure from the first pump, an output port including an output port for a forward position, and a drain for inputting a working fluid and draining it. And the neutral position control means shifts from the forward position to the neutral position. The orifice is interposed between the input port of the linear solenoid valve and the drain input port. The second pump is controlled to be driven on the condition that it is driven, and the working fluid drains from the clutch through the drain port of the linear solenoid valve, and the input port and the orifice of the linear solenoid valve from the clutch And the working fluid that drains through the drain input port. May be fluid pressure acting on the clutch by adjusting the amount ratio is assumed to be means for controlling the linear solenoid valve to gradually reduced. In this way, the fluid pressure acting on the clutch can be gradually reduced more appropriately, and a better shift feel can be realized. Further, in the power transmission device according to the present invention of these aspects, the neutral position control means is configured to shift the linear solenoid valve after driving the second pump when the forward position is shifted from the forward position to the neutral position. It is also possible to control the pressure and gradually reduce the fluid pressure acting on the clutch.

  Further, in the power transmission device of the invention, when the neutral position control means is shifted from the forward position to the neutral position, the second pump is started to be driven and supplied to the clutch. It may be a means for controlling to start the drain of the working fluid and stop the second pump after the drain is completed. By so doing, it is possible to prevent a sudden change in the fluid pressure acting on the clutch, and to obtain a better shift feel.

  In the power transmission device of the present invention, a signal pressure input port for inputting the fluid pressure from the first pump as a signal pressure, an input port connected to the output port of the linear solenoid valve, and a connection to the clutch And when the fluid pressure is input to the signal pressure input port, the fluid pressure is not input to the signal pressure input port. Sometimes, a switching valve for switching between a state where communication between the input port and the output port is blocked can be provided.

  The power transmission device of the present invention has a plurality of clutches capable of forming a plurality of different gear speeds, and the second pump outputs fluid pressure to a starting clutch among the plurality of clutches. You can also

It is a block diagram which shows the outline of a structure of the vehicle 10 carrying the power transmission device 20 as one Example of this invention. 3 is an operation table of an automatic transmission mechanism 28. FIG. 6 is a collinear diagram showing the relationship between the rotational speeds of the rotating elements of the automatic transmission mechanism. 2 is a configuration diagram showing an outline of a configuration of a hydraulic circuit 30. FIG. It is explanatory drawing explaining the drain circuit which drains the hydraulic pressure which is acting on the clutch C1, when the shift lever 91 is operated from the D position to the N position. 4 is a flowchart illustrating an example of a control routine for a DN shift executed by an ATECU 29; It is explanatory drawing which shows an example of the map for electric current command setting. It is explanatory drawing which shows a mode that C1 pressure at the time of draining is adjusted with the linear solenoid SLC1. It is explanatory drawing which shows the mode of the time change of the electric current command I * of the shift position SP, the linear solenoid SLC1, the C1 pressure of the clutch C1, and the drive command of the electromagnetic pump 70.

  Next, embodiments of the present invention will be described using examples.

  FIG. 1 is a configuration diagram showing an outline of a configuration of a vehicle 10 equipped with a power transmission device 20 as an embodiment of the present invention, FIG. 2 is an operation table of an automatic transmission mechanism 28, and FIG. 3 is an automatic transmission. FIG. 6 is a collinear diagram showing the relationship between the rotational speeds of the rotating elements of the mechanism 28;

  As shown in the figure, the power transmission device 20 according to the embodiment is configured to be mounted on, for example, an FF (front engine front drive) type vehicle 10, and receives power from the engine 12 that receives operation control by the EGECU 16. A torque converter 26 with a lock-up clutch that transmits with torque amplification, an automatic transmission mechanism 28 that transmits power from the torque converter 26 to the wheels 18a and 18b with a shift, and an ATECU 29 that controls the entire apparatus. Prepare. The ATECU 29 is communicably connected to the main ECU 90 that controls the entire vehicle together with the EGECU 16, and exchanges control signals and data related to the driving state with each other. The main ECU 90 includes a shift position SP from the shift position sensor 92 that detects the operation position of the shift lever 91, an accelerator opening Acc from the accelerator pedal position sensor 94 that detects the depression amount of the accelerator pedal 93, and a brake pedal 95. The brake switch signal BSW from the brake switch 96 that detects the depression of the vehicle, the vehicle speed V from the vehicle speed sensor 98, and the like are input.

  The torque converter 26 includes a pump impeller 26a connected to the crankshaft 14 of the engine 12, and a turbine runner 26b connected to the input shaft 22 of the automatic transmission mechanism 28 and disposed opposite to the pump impeller 26a. The pump impeller 26a The engine torque is converted into a flow of hydraulic oil, and the flow of the hydraulic oil is converted into torque on the input shaft 22 by the turbine runner 26b to transmit torque. The torque converter 26 has a built-in lock-up clutch 26c. When the lock-up clutch 26c is engaged, the engine crankshaft 21 and the input shaft 22 of the automatic transmission mechanism 28 are directly connected to each other so that the engine torque is directly applied. To communicate.

  The automatic transmission mechanism 28 includes a planetary gear unit PU, three clutches C1, C2, and C3, two brakes B1 and B2, and a one-way clutch F1. The planetary gear unit PU is configured as a Ravigneaux type planetary gear mechanism, and includes two sun gears S1 and S2 as external gears, a ring gear R as an internal gear, a plurality of short pinion gears PS meshing with the sun gear S1, and a sun gear. S2 and a plurality of long pinion gears PL that mesh with the plurality of short pinion gears PS and mesh with the ring gear R; The sun gear S1 is connected to the input shaft 22 via the clutch C1, and the sun gear S2 is connected to the input shaft 22 via the clutch C3, and its rotation is freely or prohibited by the brake B1. The ring gear R is connected to the output shaft 24. Cage, carrier CR is connected to the input shaft 24 via the clutch C2. The rotation of the carrier CR is restricted in one direction by the one-way clutch F1, and the rotation of the carrier CR is freely or prohibited by a brake B2 provided in parallel to the one-way clutch F1. The power output to the output shaft 24 is transmitted to the wheels 18a and 18b via a counter gear and a differential gear (not shown).

  Further, as shown in the operation table of FIG. 2, the automatic transmission mechanism 28 can switch between forward 1st speed to 4th speed and reverse speed by a combination of on / off of the clutches C1 to C3 and the brakes B1 and B2. Yes. FIG. 3 is a collinear diagram showing the relationship among the rotational speeds of the sun gears S1, S2, the ring gear R, and the carrier CR at each gear stage of the automatic transmission mechanism 28.

  The hydraulic transmission circuit 40 turns on and off the clutches C1 to C3 and the brakes B1 and B2 in the automatic transmission mechanism 28. FIG. 4 is a configuration diagram showing an outline of the configuration of the hydraulic circuit 40. As shown in the drawing, the hydraulic circuit 40 adjusts the hydraulic oil pumped by the mechanical oil pump 32 via the strainer 31 by power from the engine and the hydraulic oil pumped from the mechanical oil pump 32 to adjust the line pressure PL. A regulator valve 33 for generating a pressure, a linear solenoid SLT for driving the regulator valve 33 by adjusting a modulator pressure PMOD generated from a line pressure PL via a modulator valve (not shown) and outputting it as a signal pressure, and a line pressure PL Input port 42a, drive position output port (D port) 42b, reverse position output port (R port) 42c, etc. are formed, and input port 42a and output ports 42b, 42c are interlocked with the operation of shift lever 91. Manual for communication and disconnection between The hydraulic oil output from the valve 40 and the D port 42b of the manual valve 40 is input from the input port 52a via the D port oil passage 35, and the pressure is adjusted with the discharge of the hydraulic oil to the drain port 52c. A linear solenoid SLC1 output from 52b, a switching valve 60 for connecting and disconnecting the clutch fluid passage 39 connected to the output port 52b of the linear solenoid SLC1 and the clutch C1, and a check valve for suction in the sleeve 72. 74 and a discharge check valve 76 are built in, and a suction port 72a is connected to a suction oil passage 37 between the mechanical oil pump 32 and the strainer 31, and a discharge port 72b is connected to a clutch oil passage 39. When the solenoid unit 71 is turned off from on, the hydraulic oil is sucked from the suction port 72a with the opening of the check valve 74 for suction. Isoprenoid unit 71 is constituted by an electromagnetic pump 70 for discharging the sucked hydraulic oil with the opening discharge port 72b of the discharge check valve 76 when turned on from off. Although not shown, a damper for suppressing vibration of the hydraulic pressure of the clutch C <b> 1 can be attached to the clutch oil passage 39. In FIG. 4, the hydraulic systems of the clutches C2 and C3 other than the clutch C1 and the brakes B1 and B2 are omitted because they do not form the core of the present invention, but these hydraulic systems are omitted using a known linear solenoid or the like. Can be configured.

  As shown in FIG. 4, the manual valve 40 has an input port 42a, a D-position output port 42b, and an R-position output port 42c so as to communicate with a substantially cylindrical space formed in the valve body. In this space, the spool 44 having the two lands 44a and 44b slides in accordance with the shift operation of the shift lever 71, whereby the communication between the input port 42a and the output ports 42b and 42c is performed and blocked. . The manual valve 40 has a drain input port 42d in addition to the input port 42a and output ports 42b and 42c. The drain input port 42d is connected to the input port 42a and the output ports 42b and 42c. They are separated by lands 44b. When the manual valve 40 is shifted to the D position, the drain input port 42d is closed by the outer wall of the land 44b. When the manual valve 40 is shifted to the N position, the land 44b is moved to the left side in the figure. The drain input port 42d is released, and the hydraulic oil in the D port oil passage 35 is input via the drain input port 42d to be drained.

  As shown in FIG. 4, the linear solenoid SLC1 includes a solenoid 51 that drives a plunger 51a by generating an attractive force by a magnetic circuit formed by applying a current to a coil, and a D-position output port 42b. A hollow sleeve 52 formed with an input port 52a connected via the port oil passage 35, an output port 52b connected to the output port oil passage 36, and a drain port 52c, and a plunger 51a of the solenoid portion 51 A spool 54 that slides in the sleeve 52 as it is driven to adjust the opening ratio of the communication between the input port 52a and the output port 52b and the communication between the output port 52b and the drain port 52c. A general normally closed type linear solenoid composed of a spring 56 biased from the opposite side It is configured as a valve. The D port oil passage 35 is provided with a check valve 46 and an orifice 48 connected in parallel to the check valve 46. The hydraulic oil output from the D position output port 42 b of the manual valve 40 is It is supplied to the input port 52b of the linear solenoid SLC1 through the check valve 46. The reason why the orifice 48 is provided will be described later.

  As shown in FIG. 4, the switching valve 60 includes a signal pressure input port 62a for inputting the line pressure PL as a signal pressure, and an input port 62b connected to the output port 52b (output port oil passage 36) of the linear solenoid SLC1. A sleeve 62 in which various ports of the output port 62c connected to the clutch oil passage 39 are formed, a spool 64 that slides in the sleeve 62 in the axial direction, and a spring 66 that biases the spool 64 in the axial direction. It is configured. When the line pressure PL is input to the signal pressure input port 62a, the switching valve 60 overcomes the urging force of the spring 66 and the spool 64 moves to the position shown in the left half region in the figure, and the input port 62b and the output port 62c communicates with the output port 52b of the linear solenoid SLC1 and the clutch oil passage 39. When the line pressure PL is not input to the signal pressure input port 62a, the spool 64 is urged by the biasing force of the spring 66. By moving to the position shown in the middle right half region and blocking the communication between the input port 62b and the output port 62c, the communication between the output port 52b of the linear solenoid SLC1 and the clutch oil passage 39 is blocked.

  FIG. 5 is an explanatory diagram for explaining a drain circuit for draining the hydraulic pressure acting on the clutch C1 when the shift lever 91 is operated from the D position to the N position. Note that the switching valve 60 is not shown because it is considered that the clutch oil passage 39 and the output port oil passage 36 are connected. Consider a state in which the energization of the normally closed linear solenoid SLC1 is turned off. In this state, the communication between the input port 52a and the output port 52b of the linear solenoid SLC1 is cut off, and the output port 52b and the drain port 52c are connected, so that the C1 pressure that is the hydraulic pressure acting on the clutch C1 is Draining is performed along a first path through the clutch oil path 39, the output port 52b of the linear solenoid SLC1, and the drain port 52c in this order. Next, a state where the linear solenoid SLC1 is turned on with the maximum energization amount will be considered. In this state, the input port 52a and the output port 52b of the linear solenoid SLC1 are communicated with each other and the communication between the output port 52b and the drain port 52c is interrupted. Therefore, the pressure C1 is applied to the clutch oil passage 39 and the linear solenoid SLC1. Draining is performed through a second path through the output port 52b, the input port 52a, the orifice 48, the D port oil path 35, and the drain input port 42d of the manual valve 40 in this order. Considering the state in which the energization amount of the linear solenoid SLC1 is adjusted, the input port 52a and the output port 52b of the linear solenoid SLC1 communicate with each other at an opening ratio corresponding to the stroke amount of the spool 54, and the output port 52b and the drain are connected. Since the port 52c communicates, a part of the C1 pressure is drained through the first path, and the remainder is drained through the second path. In the second path, the orifice 48 is interposed, and the flow of hydraulic oil is limited. Therefore, the rate of decrease in the C1 pressure during draining is smaller than that in the first path. Therefore, the C1 pressure during drainage can be adjusted by controlling the linear solenoid SLC1.

  In the vehicle 10 of the embodiment configured in this way, when the shift lever 91 is running at the D (drive) running position, the vehicle speed V is set to 0, the accelerator is turned off, the brake switch signal BSW is turned on, and so on. The engine 12 is automatically stopped when all of the automatic stop conditions are satisfied. When the engine 12 is automatically stopped, thereafter, the engine 12 that has been automatically stopped is automatically started when a preset automatic start condition such as the brake switch signal BSW being turned off is satisfied.

  In the vehicle 10 of the embodiment, when the automatic stop condition is satisfied and the engine 12 is automatically stopped, the mechanical oil pump 32 is also stopped accordingly, so the line pressure PL is released and the spool 64 of the switching valve 60 is output. The connection between the port oil passage 36 and the clutch oil passage 39 is cut off. Therefore, by driving the electromagnetic pump 70 in which the discharge port 62b is connected to the clutch oil passage 39, hydraulic pressure can be applied to the clutch C1. Next, when the engine 12 that has been stopped due to the automatic start condition is automatically started, the mechanical oil pump 32 is activated accordingly, so that the line pressure PL is supplied and the spool 64 of the switching valve 60 is supplied. Connects the output port oil passage 36 and the clutch oil passage 39. Therefore, by applying hydraulic pressure to the clutch C1 from the linear solenoid SLC1, the vehicle can be started with the clutch C1 completely engaged. Thus, by driving the electromagnetic pump 70 and applying hydraulic pressure to the clutch C1 while the engine 12 is automatically stopped, the clutch C1 is quickly moved by the linear solenoid SLC1 immediately after the engine 12 is automatically started. Since it can be engaged, the start can be performed smoothly. In the embodiment, the electromagnetic pump 70 is designed so that its hydraulic performance can be replenished with hydraulic oil by an amount leaking from a seal ring or the like provided between the piston of the clutch C1 and the drum. .

  Next, the operation of the vehicle 10 of the embodiment configured as described above, particularly the operation when the shift lever 91 is operated from the D position to the N position will be described. FIG. 6 is a flowchart illustrating an example of a control routine at the time of the DN shift executed by the ATECU 29. This routine is executed when the shift position SP from the shift position sensor 92 is changed from the D position to the N position.

  When the D-N shift control routine is executed, the ATECU 29 first starts driving the electromagnetic pump 70 (step S100) and sets a current command I * for the solenoid unit 51 of the linear solenoid SLC1 (step S110). The linear solenoid SLC1 is controlled with the set current command I * (step S120), and the process returns to step S110 until the current command I * becomes 0 (step S130). Here, the current command I * is obtained in advance as a current command setting map by storing the relationship between the elapsed time t from the start of execution of this routine and the current command I *, and given the elapsed time t. It was set by deriving the corresponding current command I * from the map. FIG. 7 shows an example of a current command setting map, and FIG. 8 shows how the linear solenoid SLC1 adjusts the C1 pressure during draining. Line A in FIG. 8 shows the time change of the C1 pressure when the energization of the linear solenoid SLC1 is turned off, and line B shows the time change of the C1 pressure when the linear solenoid SLC1 is turned on with the maximum energization amount. Show. As shown in the figure, the C1 pressure can be adjusted within the range of the area surrounded by the lines A and B when draining, and the current command I so that the C1 pressure gradually decreases within this range. The clutch C1 is disengaged by setting * and controlling the linear solenoid SLC1. This suppresses the occurrence of a shock when the clutch C1 is disengaged. In the embodiment, if the C1 pressure is drained only by the linear solenoid SLC1, the C1 pressure is suddenly reduced, and the clutch C1 is also suddenly released to generate a shock. The C1 pressure was drained by the linear solenoid SLC1 while pumping hydraulic oil from the pump 70 to the clutch C1. Since this electromagnetic pump 70 is used to supply hydraulic pressure to the clutch C1 while the engine 12 is automatically stopped, it is not necessary to provide a new electromagnetic pump only for draining the C1 pressure. When the current command I * becomes 0, the routine waits for a predetermined time Tref to elapse (step S140), stops driving the electromagnetic pump 70 (step S150), and ends this routine. Here, the predetermined time Tref is a margin that is set so that the driving of the electromagnetic pump 70 is not stopped before the drain of the C1 pressure is completed, and can be set to 100 msec or 200 msec, for example.

  FIG. 9 is an explanatory diagram showing changes over time in the shift position SP, the current command I * of the linear solenoid SLC1, the C1 pressure of the clutch C1, and the drive command of the electromagnetic pump 70. As shown in the figure, when the shift position SP is changed from the D position to the N position (time t1), the driving of the electromagnetic pump 70 is started when a predetermined time (for example, 10 msec) has elapsed from the time t1 (time). t2), the current command I * is set so as to gradually approach the value 0 from time t3, and the linear solenoid SLC1 is controlled. At this time, since the C1 pressure gradually decreases with the control of the linear solenoid SLC1, no shock occurs when the clutch C1 is disengaged. When the current command I * becomes a value 0 at time t4, it waits for a predetermined time Tref that can be determined that the engagement of the clutch C1 is released (drain is completed) (time t5). Stop driving.

  According to the power transmission device 20 of the embodiment described above, the discharge port 72b of the electromagnetic pump 70 is connected to the clutch oil passage 39 of the clutch C1, and the output port 52b of the linear solenoid SLC1 is connected via the switching valve 60. The hydraulic solenoid circuit 40 is configured by connecting the input port 52a of the linear solenoid SLC1 and the drain input port 42d of the manual valve 40 via the orifice 48, and when the shift lever 91 is operated from the D position to the N position, The hydraulic oil is pumped from the electromagnetic pump 70 to the clutch oil passage 39 and is drained directly from the output port 52b of the linear solenoid SLC1 to the drain port 52c, and the manual valve 40 from the output port 52b through the input port 52a and the orifice 48. Drain input port 4 By adjusting the ratio of the flow rate that drains to d, the C1 pressure is gradually reduced to release the engagement of the clutch C1, so that it is possible to suppress a shock when releasing the engagement of the clutch C1. Can do. In addition, since the electromagnetic pump 70 for applying hydraulic pressure to the clutch C1 is used while the engine 12 is automatically stopped, the entire apparatus is compared with a separate accumulator for accumulating the C1 pressure of the clutch C1. Can be miniaturized.

  In the power transmission device 20 of the embodiment, the driving of the electromagnetic pump 70 is stopped after a predetermined time Tref elapses after the current command I * of the linear solenoid SLC1 becomes 0 when the C1 pressure is drained. However, the driving of the electromagnetic pump 70 may be stopped immediately when the current command I * becomes 0. Further, in the embodiment, when a predetermined time elapses after the shift position SP is changed from the D position to the N position (time t1 in FIG. 9) (time t2), the driving of the electromagnetic pump 70 is started. However, the driving of the electromagnetic pump 70 may be started immediately when the position is changed to the N position.

  In the power transmission device 20 of the embodiment, the switching valve 60 is driven using the line pressure PL. However, the switching valve 60 may be driven using the modulator pressure PMOD obtained by reducing the line pressure PL via a modulator valve (not shown). Alternatively, the line pressure PL and the modulator pressure may be supplied to the switching valve 60 via the solenoid valve and driven using this solenoid valve.

  In the power transmission device 20 according to the embodiment, the automatic transmission mechanism 28 of the first forward speed to the fourth forward four-speed shift is incorporated. However, the present invention is not limited to this. Any number of automatic transmission mechanisms may be incorporated, such as the above-described gear positions.

  Here, the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 12 corresponds to a “motor”, the mechanical oil pump 32 corresponds to a “first pump”, the manual valve 40 corresponds to a “manual valve”, and the linear solenoid SLC1 corresponds to a “linear solenoid valve”. ”, The electromagnetic pump 70 corresponds to“ second pump ”, and the ATECU 29 corresponds to“ neutral position control means ”. Here, the “prime mover” is not limited to an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, and may be any type of internal combustion engine such as a hydrogen engine, Any type of prime mover may be used as long as it can output power, such as an electric motor other than the internal combustion engine. The “second pump” is not limited to an electromagnetic pump that pumps hydraulic oil by electromagnetic force, but generates fluid pressure by driving with electric power, such as an electric pump that pumps hydraulic oil by power from an electric motor. Any type of pump can be used as long as it can be used. The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  The embodiments of the present invention have been described using the embodiments. However, the present invention is not limited to these embodiments, and can be implemented in various forms without departing from the gist of the present invention. Of course you get.

  The present invention is applicable to the automobile industry.

  DESCRIPTION OF SYMBOLS 10 Vehicle, 12 Engine, 14 Crankshaft, 16 EGECU (engine ECU), 20 Power transmission device, 22 Input shaft, 24 Output shaft, 26 Torque converter, 26a Pump impeller, 26b Turbine runner, 26c Lock-up clutch, 28 Automatic transmission Mechanism, 29 ATECU, 30 Hydraulic circuit, 31 Strainer, 32 Mechanical oil pump, 33 Regulator valve, 34 Line pressure oil path, 35 D port oil path, 36 Output port oil path, 37 Suction oil path, 39 Clutch Oil passage, 40 Manual valve, 42a Input port, 42b Drive position output port, 42c Reverse position output port, 44 Spool, 44a, 44b Land, SLC1 Linear solenoid, 51 Solenoid part, 51 Plunger, 52 sleeve, 52a input port, 52b output port, 52c drain port, 54 spool, 56 spring, 60 switching valve, 62 sleeve, 62a signal pressure input port, 62b input port, 62c output port, 64 spool, 66 spring, 70 Electromagnetic pump, 71 Solenoid part, 72 Sleeve, 74 Check valve for suction, 76 Check valve for discharge, 90 Main ECU, 91 Shift lever, 92 Shift position sensor, 93 Accelerator pedal, 94 Accelerator pedal position sensor, 95 Brake Pedal, 96 brake switch, 98 vehicle speed sensor, SLT linear solenoid, S1, S2 sun gear, R ring gear, PS short pinion gear, PL long pinion gear, CR carrier, C ~C3 clutch, B1, B2 brake, F1 the one-way clutch.

Claims (9)

A power transmission device including a clutch mounted on a vehicle and transmitting power from a prime mover to an axle,
A first pump that generates fluid pressure by power from the prime mover;
A manual valve for switching whether to supply the fluid pressure from the first pump to the clutch according to a shift operation, and for draining the working fluid supplied to the clutch when the shift operation is performed to a neutral position; ,
A second pump for generating fluid pressure by operating upon receiving power supply and supplying the fluid to the clutch;
And a neutral position control means for controlling the second pump so as to be driven on the condition that a shift operation is performed from the forward position to the neutral position. The power transmission device according to claim 1,
A linear solenoid valve that regulates fluid pressure from the manual valve and supplies the clutch to the clutch;
The neutral position control means includes the second pump and the linear solenoid valve so that the fluid pressure acting on the clutch is gradually reduced on the condition that the forward operation position is shifted to the neutral position. A power transmission device characterized in that The power transmission device according to claim 2,
The manual valve has an input port for inputting fluid pressure from the first pump, an output port including an output port for forward position, and an input port for drain for inputting working fluid and draining.
Comprising an orifice interposed between the input port of the linear solenoid valve and the input port for drain;
The neutral position control means controls the second pump so as to be driven on the condition that the forward operation position is shifted to the neutral position, and from the clutch through the drain port of the linear solenoid valve. The fluid pressure acting on the clutch is adjusted by adjusting the flow rate of the working fluid draining from the clutch through the input port of the linear solenoid valve, the orifice, and the drain input port. A means for controlling the linear solenoid valve so as to gradually decrease.   When the neutral position control means is shifted from the forward position to the neutral position, after the second pump is driven, the control means controls the linear solenoid valve to control the fluid pressure acting on the clutch. 4. The power transmission device according to claim 2, wherein the power transmission device is a means for gradually decreasing. A signal pressure input port for inputting the fluid pressure from the first pump as a signal pressure, an input port connected to the output port of the linear solenoid valve, and an output port connected to the clutch, When the fluid pressure is input to the signal pressure input port, the input port communicates with the output port. When the fluid pressure is not input to the signal pressure input port, the input port and the output port The power transmission device according to any one of claims 2 to 4, further comprising a switching valve that switches between a state where communication is blocked. The neutral position control means starts driving the second pump and starts draining the working fluid supplied to the clutch on the condition that the shift operation from the forward position to the neutral position is performed. The power transmission device according to any one of claims 1 to 5 , wherein the power transmission device is a means for controlling the second pump to stop after the drain is completed.   The power transmission device according to claim 1, wherein the second pump is an electromagnetic pump. The power transmission device according to any one of claims 1 to 7,
Having a plurality of clutches capable of forming a plurality of different gear positions,
The second pump outputs a fluid pressure to a starting clutch among the plurality of clutches. The power transmission device according to any one of claims 1 to 8, wherein the prime mover is an internal combustion engine capable of automatic stop and automatic start.

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