JP2018112240A - Hydraulic control device of automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a fastening lug or fastening shock of a friction fastening element fastened by select operation, when performing the select operation to a traveling range position.SOLUTION: A hydraulic control device of a belt type continuously variable transmission is equipped with an oil pump 70; a manual valve 77; a forward clutch 31; and a reverse brake 32. To the manual valve 77, a forward moving drain oil path 721 which drains oils to the forward clutch 31, and a backward moving drain oil path 722 which drains oil to the reverse brake 32 are connected. The hydraulic control device of the belt type continuously variable transmission, is provided with a communication path 723 which communicates the forward moving drain oil path 721 and the backward moving drain oil path 722 connected to drain ports 77d and 77e of the manual valve 77; and a drain pressure solenoid valve 76 in the communication path 723. The drain pressure solenoid valve 76 maintains the filling of the oil to the forward moving drain oil path 721 and the backward moving drain oil path 722 through the communication path 723, regardless of a switching position of the manual valve 77.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hydraulic control device for an automatic transmission that includes a manual valve that switches a supply destination of oil supplied from a hydraulic source in accordance with a selection operation to a select lever.

  Conventionally, a manual valve that switches a supply destination of oil supplied from a hydraulic power source in accordance with a selection operation to a selection lever is provided. A hydraulic control device for an automatic transmission provided with an exhaust valve that controls to change the rate of decrease in drain pressure from the manual valve is known (for example, see Patent Document 1).

JP 2005-273879 A

  However, since the conventional device only changes the rate of decrease of the drain pressure from the manual valve, for example, when the D range position is selected and a predetermined time has elapsed, the R range pressure oil passage is filled with oil. It will be in a state where oil has not been drained. Therefore, when the D → R selection operation is performed from the state where the D range position is selected, the R range fastening element is fastened after waiting for the oil to be filled in the R range pressure oil passage in the oil omission state. And a fastening lug is generated. Similarly, when the R → D select operation is performed, a fastening lug occurs. Further, when the N range position is selected, both the D range pressure oil passage and the R range pressure oil passage are in a state of oil leakage that is not filled with oil. Therefore, a fastening lug also occurs when an N → D select operation or an N → R select operation is performed. Therefore, there has been a problem that a fastening shock occurs when the hydraulic pressure is rapidly applied in order to reduce such a fastening lug.

  The present invention has been made paying attention to the above problem, and an object of the present invention is to reduce the fastening lugs and fastening shocks of the friction fastening elements fastened by the select operation when performing the select operation to the travel range position.

In order to achieve the above object, the present invention includes a hydraulic pressure source, a manual valve, a forward frictional engagement element, a reverse frictional engagement element, a forward drain oil path, and a reverse drain oil path.
The manual valve switches the supply destination of the oil supplied from the hydraulic source according to the selection operation to the select lever.
The forward friction fastening element is fastened when the select lever selects the forward range position.
The reverse friction engagement element is engaged when the select lever selects the reverse range position.
The forward drain oil passage drains oil to the forward frictional engagement element.
The reverse drain oil passage drains oil to the reverse friction engagement element.
In this automatic transmission hydraulic control device, a communication passage that communicates the forward drain oil passage and the reverse drain oil passage connected to the drain port of the manual valve is provided, and an oil filling means is provided in the communication passage.
The oil filling means maintains oil filling to the forward drain oil passage and the reverse drain oil passage through the communication passage regardless of the manual valve switching position.

That is, when performing the selection operation to the travel range position, the present inventor has confirmed that the oil applied to the frictional engagement element that is fastened by the selection operation is in an oil draining state before the selection operation. And found that a fastening shock occurs. Since this oil drainage is caused by the oil being discharged through the manual valve, it is desired to abolish the manual valve itself, but it cannot be abolished to prevent interlock.
Paying attention to these points, a communication passage that connects the forward drain oil passage and the reverse drain oil passage is provided, and an oil filling means is provided in the communication passage. As a result, regardless of the manual valve switching position, oil filling to the forward drain oil passage and the reverse drain oil passage is maintained through the communication passage, and there is no fastening lug or fastening shock due to oil leakage. Reduced.
As a result, when performing the selection operation to the travel range position, it is possible to reduce the engagement lug and the engagement shock of the friction engagement element that is engaged by the selection operation.

1 is an overall system diagram showing a drive system and a control system of an engine vehicle equipped with a belt-type continuously variable transmission to which a hydraulic control device of Embodiment 1 is applied. 1 is a hydraulic control circuit diagram showing a main part of a hydraulic control circuit including a manual valve according to Embodiment 1. FIG. It is an action explanatory view showing a hydraulic control action when a D range position is selected in a hydraulic control circuit provided with a manual valve of a comparative example. It is an action explanatory view showing the oil pressure control action when the N range position is selected in the oil pressure control circuit provided with the manual valve of the comparative example. FIG. 6 is an operation explanatory diagram illustrating a hydraulic control operation when an N-range position is selected in the hydraulic control circuit including the manual valve according to the first embodiment. FIG. 6 is an operation explanatory diagram illustrating a hydraulic control operation when a D range position is selected in the hydraulic control circuit including the manual valve according to the first embodiment. FIG. 6 is an operation explanatory diagram illustrating a hydraulic control operation when an R range position is selected in the hydraulic control circuit including the manual valve according to the first embodiment. It is a hydraulic control circuit diagram which shows the principal part of the hydraulic control circuit provided with the manual valve of Example 2.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the best mode for realizing a hydraulic control device for an automatic transmission according to the present invention will be described based on Example 1 and Example 2 shown in the drawings.

First, the configuration will be described.
The hydraulic control apparatus according to the first embodiment is applied to an engine vehicle equipped with a belt type continuously variable transmission called a variator as an automatic transmission. Hereinafter, the configuration of the first embodiment will be described by dividing it into “a whole system configuration” and “a hydraulic control circuit configuration including a manual valve”.

[Overall system configuration]
FIG. 1 shows a drive system and a control system of an engine vehicle equipped with a belt-type continuously variable transmission to which the hydraulic control device of the first embodiment is applied. The overall system configuration will be described below with reference to FIG.

  As shown in FIG. 1, the drive system of the engine vehicle includes an engine 1, a torque converter 2, a forward / reverse switching mechanism 3, a variator 4 (automatic transmission), a final reduction mechanism 5, and drive wheels 6, 6. And.

  The engine 1 can control the output torque by an engine control signal from the outside, in addition to the output torque control by the accelerator operation by the driver. The engine 1 includes an output torque control actuator 10 that performs output torque control by a throttle valve opening / closing operation, a fuel cut operation, and the like.

  The torque converter 2 is a starting element having a torque increasing function. When the torque increasing function is not required, the torque converter 2 includes a lock-up clutch 20 that can directly connect the engine output shaft 11 (= torque converter input shaft) and the torque converter output shaft 21. Have. The torque converter 2 is provided with a pump impeller 23 connected to the engine output shaft 11 via a converter housing 22, a turbine runner 24 connected to the torque converter output shaft 21, and a case via a one-way clutch 25. The stator 26 is a component.

  The forward / reverse switching mechanism 3 is a mechanism that switches an input rotation direction to the variator 4 between a forward rotation direction during forward travel and a reverse rotation direction during reverse travel. The forward / reverse switching mechanism 3 includes a double pinion planetary gear 30, a forward clutch 31 (FWD / C: forward frictional engagement element) using a plurality of clutch plates, and a reverse brake 32 (REV / B) using a plurality of brake plates. : Renewal friction engagement element). The forward clutch 31 is hydraulically engaged by the forward clutch pressure Pfc when the forward range position (D range position) is selected. The reverse brake 32 is hydraulically engaged with the reverse brake pressure Prb when the reverse range position (R range position) is selected. Note that both the forward clutch 31 and the reverse brake 32 are released when the neutral range position (N range position) is selected.

  The variator 4 has a primary pulley 42, a secondary pulley 43, and a pulley belt 44, and changes a gear ratio (a ratio between a variator input rotation speed and a variator output rotation speed) steplessly by changing a belt contact diameter. A continuously variable transmission function is provided. The primary pulley 42 includes a fixed pulley 42 a and a slide pulley 42 b arranged on the same axis as the variator input shaft 40, and the slide pulley 42 b is slid by the primary pressure Ppri guided to the primary pressure chamber 45. The secondary pulley 43 includes a fixed pulley 43 a and a slide pulley 43 b that are arranged coaxially with the variator output shaft 41, and the slide pulley 43 b is slid by the secondary pressure Psec guided to the secondary pressure chamber 46. The pulley belt 44 is stretched between a sheave surface that forms a V shape of the primary pulley 42 and a sheave surface that forms a V shape of the secondary pulley 43. The pulley belt 44 is formed of two sets of laminated rings in which a large number of annular rings are stacked from the inside to the outside and a plurality of punched plate members, and is attached by being laminated in an annular manner by being sandwiched along the two sets of laminated rings. It is composed of elements. The pulley belt 44 may be a chain-type belt in which a large number of chain elements arranged in the pulley traveling direction are coupled by pins penetrating in the pulley axial direction.

  The final deceleration mechanism 5 is a mechanism that decelerates the variator output rotation speed from the variator output shaft 41 and transmits it to the left and right drive wheels 6 and 6 while providing a differential function. The final reduction mechanism 5 is provided as a reduction gear mechanism at the outer peripheral position of the first gear 52 provided on the variator output shaft 41, the second gear 53 and the third gear 54 provided on the idler shaft 50, and the differential case. And a fourth gear 55. The differential gear mechanism includes a differential gear 56 interposed between the left and right drive shafts 51, 51.

  As shown in FIG. 1, the engine vehicle control system includes a hydraulic control unit 7 that is a hydraulic control system and a CVT control unit 8 that is an electronic control system.

  The hydraulic control unit 7 regulates the primary pressure Ppri to the primary pressure chamber 45, the secondary pressure Psec to the secondary pressure chamber 46, the forward clutch pressure Pfc to the forward clutch 31, the reverse brake pressure Prb to the reverse brake 32, and the like. . The hydraulic control unit 7 includes an oil pump 70 (hydraulic power source) that is rotationally driven by the engine 1 that is a driving source for traveling, and a hydraulic control circuit 71 that adjusts various control pressures based on the discharge pressure from the oil pump 70. And comprising. The hydraulic control circuit 71 includes a line pressure solenoid valve 72, a primary pressure solenoid valve 73, a secondary pressure solenoid valve 74, a clutch / brake pressure solenoid valve 75, and a drain pressure solenoid valve 76. Each solenoid valve 72, 73, 74, 75, 76 is regulated by a command value output from the CVT control unit 8.

  The line pressure solenoid valve 72 adjusts the discharge pressure from the oil pump 70 to the commanded line pressure PL according to the line pressure command value output from the CVT control unit 8. The line pressure PL is a source pressure when adjusting various control pressures, and is a hydraulic pressure that suppresses belt slip and clutch slip against torque transmitted through the drive system.

  The primary pressure solenoid valve 73 adjusts the pressure to the primary pressure Ppri that is commanded using the line pressure PL that defines the upper limit pressure as the original pressure in accordance with the primary pressure command value output from the CVT control unit 8. The secondary pressure solenoid valve 74 adjusts the pressure to the secondary pressure Psec that is commanded using the line pressure PL that defines the upper limit pressure as the original pressure in accordance with the secondary pressure command value output from the CVT control unit 8. The detailed configuration of the clutch / brake pressure solenoid valve 75 and the drain pressure solenoid valve 76 will be described later.

The CVT control unit 8 performs line pressure control, transmission hydraulic pressure control, forward / reverse switching control, and the like. In the line pressure control, a command value for obtaining a target line pressure corresponding to the throttle opening degree is output to the line pressure solenoid valve 72. In the shift control, when the target speed ratio (target primary rotational speed Npri ^* ) is determined, a hydraulic pressure command value for obtaining the determined target speed ratio (target primary rotational speed Npri ^* ) is sent to the primary pressure solenoid valve 73 and the secondary pressure solenoid valve 74. Output. In the forward / reverse switching control, when the D range position is selected, a command value for engaging the forward clutch 31 is output to the clutch / brake pressure solenoid valve 75. If the R range position is selected, a command value for engaging the reverse brake 32 is output to the clutch / brake pressure solenoid valve 75.

  The CVT control unit 8 includes a turbine rotation speed sensor 80, a vehicle speed sensor 81, a secondary pressure sensor 82, an oil temperature sensor 83, an inhibitor switch 84, a brake switch 85, an accelerator opening sensor 86, a primary pressure sensor 87, and a longitudinal G sensor 89. , Etc., sensor information and switch information are input. Further, engine torque information is input from the engine control unit 88 to which sensor information from the engine rotation speed sensor 12 is input, and an engine torque request is output to the engine control unit 88. The inhibitor switch 84 detects a range position (D range position, N range position, R range position, etc.) selected by a select lever 9 described later, and outputs a range position signal corresponding to the range position.

[Hydraulic control circuit configuration with manual valve]
FIG. 2 shows a main part of a hydraulic control circuit 71 including the manual valve 77 according to the first embodiment. The hydraulic control circuit configuration will be described below with reference to FIG.

  As shown in FIG. 2, the hydraulic control circuit 71 included in the hydraulic control unit 7 includes a clutch / brake pressure solenoid valve 75, a drain pressure solenoid valve 76 (oil filling means), and a manual valve 77.

  The clutch / brake pressure solenoid valve 75 includes a spool valve portion having a line pressure port 75a, an output pressure port 75b, a feedback pressure port 75c, and a drain port 75d, and a solenoid portion having a solenoid 75e that applies electromagnetic force to the spool. .

  A line pressure oil passage 711 that guides a line pressure PL that defines an upper limit pressure is connected to the line pressure port 75a. An output pressure oil passage 712 for outputting the regulated clutch pressure or brake pressure to the manual valve 77 is connected to the output pressure port 75b. A feedback pressure oil passage 713 is connected to the feedback pressure port 75c to guide the feedback control pressure to the spool via the orifice. A command value input line 714 for inputting a command value from the CVT control unit 8 is connected to the solenoid 75e.

  This clutch / brake pressure solenoid valve 75 is commanded with the line pressure PL defining the upper limit pressure as the original pressure in accordance with the forward clutch pressure command value output from the CVT control unit 8 when the D range position is selected. Reduce the pressure to the forward clutch pressure Pfc. Also, when the R range position is selected, the line pressure PL that defines the upper limit pressure is reduced to the commanded reverse brake pressure Prb according to the reverse brake pressure command value output from the CVT control unit 8. . That is, it is a valve that serves as both a forward clutch pressure solenoid valve and a reverse brake pressure solenoid valve.

  The drain pressure solenoid valve 76 includes a spool valve portion having a source pressure port 76a, a drain pressure port 76b, a feedback pressure port 76c, and a drain port 76d, and a solenoid portion having a solenoid 76e that applies electromagnetic force to the spool.

  An original pressure oil passage 715 is connected to the original pressure port 76a to guide the original pressure obtained by reducing the line pressure PL by a pressure reducing valve (not shown). A drain pressure oil passage 716 that outputs the regulated drain pressure Pdr to the manual valve 77 is connected to the drain pressure port 76b. A feedback pressure oil passage 717 that guides the feedback drain pressure to the spool via the orifice is connected to the feedback pressure port 76c. A command value input line 718 for inputting a command value from the CVT control unit 8 is connected to the solenoid 76e.

  The drain pressure solenoid valve 76 is an oil filling means capable of controlling the drain pressure Pdr within a hydraulic pressure range where no transmission torque is generated in the forward clutch 31 and the reverse brake 32. In other words, regardless of the selected range position, the drain pressure solenoid valve 76 is set to the drain pressure Pdr commanded using the decompressed line pressure PL as the source pressure in accordance with the drain pressure command value output from the CVT control unit 8. Adjust the vacuum.

  Here, the “drain pressure Pdr” refers to a hydraulic pressure that is suppressed below a return pressure corresponding to a biasing force by a return spring that biases the hydraulic pistons of the forward clutch 31 and the reverse brake 32 that are friction engagement elements to the release side. . In other words, it is a hydraulic pressure that can maintain oil filling (oil filling) in the hydraulic circuit and that does not generate transmission torque in the forward clutch 31 and the reverse brake 32.

  The manual valve 77 includes an input pressure port 77a, a D range pressure port 77b, an R range pressure port 77c, a forward drain port 77d, and a reverse drain port 77e, and a spool 77f that can slide the valve hole. .

  An output pressure oil passage 712 from the clutch / brake pressure solenoid valve 75 is connected to the input pressure port 77a. A D range pressure oil passage 719 (forward pressure supply oil passage) that guides the forward clutch pressure to the piston oil chamber of the forward clutch 31 is connected to the D range pressure port 77b. An R range pressure oil passage 720 (reverse pressure supply oil passage) that guides the reverse brake pressure to the piston oil chamber of the reverse brake 32 is connected to the R range pressure port 77c. A forward drain oil passage 721 is connected to the forward drain port 77d. A reverse drain oil passage 722 is connected to the reverse drain port 77e.

  The end portion of the forward drain oil passage 721 and the end portion of the reverse drain oil passage 722 are connected by a communication passage 723 that connects both the oil passages 721 and 722. The passage diameter L1 of the communication path 723 is set smaller than the oil path diameter L2 of the D range pressure oil path 719 and the oil path diameter L2 of the R range pressure oil path 720. A drain pressure oil passage 716 from the drain pressure solenoid valve 76 is connected to the intermediate position with respect to the oil passage length direction of the communication passage 723.

  The spool 77f slides in the valve hole in response to a selection operation on the selection lever 9, and switches between communication / blocking between the ports 77a, 77b, 77c, 77d, and 77e. The spool 77f and the select lever 9 may be a linkage method (mechanically connected method) in which the spool 77f is slid by a select operation force applied to the select lever 9. Alternatively, a by-wire method (method without mechanical connection) in which the select position is detected and the spool 77f is slid using an actuator may be used.

  That is, when the N range position is selected by the select lever 9, the spool 77f of the manual valve 77 is at the position shown in FIG. Therefore, the communication between the input pressure port 77a and the D range pressure port 77b is blocked, and the communication between the input pressure port 77a and the R range pressure port 77c is blocked. The D range pressure port 77b and the forward drain port 77d are communicated with each other, and the R range pressure port 77c and the reverse drain port 77e are communicated with each other.

  When the D range position is selected by the select lever 9, the spool 77f of the manual valve 77 moves upward from the position shown in FIG. 2 (see FIG. 6). Therefore, the input pressure port 77a and the D range pressure port 77b are communicated, and the communication between the input pressure port 77a and the R range pressure port 77c is blocked. Then, the communication between the D range pressure port 77b and the forward drain port 77d is cut off, and the R range pressure port 77c and the reverse drain port 77e are communicated.

  When the R range position is selected by the select lever 9, the spool 77f of the manual valve 77 moves downward from the position shown in FIG. 2 (see FIG. 7). Therefore, the communication between the input pressure port 77a and the D range pressure port 77b is blocked, and the input pressure port 77a and the R range pressure port 77c are communicated. Then, the D range pressure port 77b and the forward drain port 77d are communicated, and the communication between the R range pressure port 77c and the reverse drain port 77e is blocked.

Next, the operation will be described.
The effects of the first embodiment are as follows: “hydraulic control action by range position switching in comparative example”, “hydraulic control action at each range position”, “hydraulic control action by select operation”, “characteristic action of hydraulic control by select operation” It is divided and explained.

[Hydraulic control action by switching range position in comparative example]
Hereinafter, based on FIG.3 and FIG.4, the hydraulic control effect | action by the range position switching in a comparative example is demonstrated. Here, a hydraulic control circuit including a manual valve in which the forward drain port and the reverse drain port are not in communication is used as a comparative example.

  The D range position is selected by the hydraulic control circuit of the comparative example. At this time, the spool of the manual valve is in the position shown in FIG. 3, the input pressure port and the D range pressure port are communicated, and the communication between the input pressure port and the R range pressure port is blocked. For this reason, the forward clutch pressure Pfc regulated by the clutch / brake pressure solenoid valve is forward clutch (FWD / C) via the output pressure oil passage → input pressure port → D range pressure port → D range pressure oil passage. And the forward clutch (FWD / C) is engaged.

  On the other hand, on the reverse brake (REV / B) side, when the D range position is selected, the R range pressure port communicates with the reverse drain port. For this reason, the oil filled in the piston oil chamber and the R range pressure oil passage of the reverse brake (REV / B) is discharged via the R range pressure oil passage → R range pressure port → reverse drain port. Therefore, in the D range position, the piston oil chamber of the reverse brake (REV / B) and the R range pressure oil passage are in an oil-spilling state where the oil is empty.

  Therefore, when the D → R select operation is performed from the state shown in FIG. 3 in which the D range position is selected, the oil is filled in the piston oil chamber and R range pressure oil passage of the reverse brake (REV / B) in the oil-released state. The R range fastening element is fastened after waiting to be done. In other words, the reverse brake (REV / B) is engaged after the precharge phase of filling the piston oil chamber and R range pressure oil passage with oil, and the reverse brake (REV / B) transmits torque from the select operation. The time required to reach a fastening state having a capacity is increased, and so-called fastening lugs are generated. Similarly, when the R → D selection operation is performed, an engagement lag is generated from the selection operation until the forward clutch (FWD / C) reaches an engagement state having a transmission torque capacity.

  The N range position is selected by the hydraulic control circuit of the comparative example. At this time, the spool of the manual valve is in the position shown in FIG. 4, and the communication between the input pressure port and the D range pressure port is blocked and the communication between the input pressure port and the R range pressure port is blocked. The D range pressure port communicates with the forward drain port, and the R range pressure port communicates with the reverse drain port.

  For this reason, the oil filled in the piston oil chamber and the D range pressure oil passage of the forward clutch (FWD / C) is discharged via the D range pressure oil passage → D range pressure port → forward drain port. Similarly, the oil filled in the piston oil chamber and the R range pressure oil passage of the reverse brake (REV / B) is discharged via the R range pressure oil passage → R range pressure port → reverse drain port. As a result, the piston oil chamber and D-range pressure oil passage of the forward clutch (FWD / C), and the piston oil chamber and R-range pressure oil passage of the reverse brake (REV / B) are in an oil-free state where the oil is empty.

  Therefore, when the N → D select operation at the forward start and the N → R select operation at the reverse start are performed, the forward clutch (FWD) is passed through the precharge phase in which the piston oil chamber or the range pressure oil passage is filled with oil. / C) and reverse brake (REV / B). Therefore, a fastening lug is generated from the selection operation until the friction fastening element reaches a fastening state having a transmission torque capacity.

  Therefore, if the clutch pressure is increased and the hydraulic pressure is rapidly applied in order to reduce such engagement lugs, the angular acceleration of the turbine runner of the torque converter increases and the inertia torque of the turbine runner rises. Therefore, when the forward clutch (FWD / C) or the reverse brake (REV / B) is engaged, an engagement shock that fluctuates the front and rear G of the vehicle due to the increase of the inertia torque of the turbine runner is generated.

[Hydraulic control at each range position]
Hereinafter, the hydraulic control operation when the N range position, the D range position, and the R range position are selected will be described with reference to FIGS.

(N range position: Fig. 5)
When the N range position is selected by the select lever 9, the spool 77f of the manual valve 77 is in the position shown in FIG. For this reason, the communication between the input pressure port 77a and the D range pressure port 77b is blocked, and the communication between the input pressure port 77a and the R range pressure port 77c is blocked. When the N range position is selected, a zero hydraulic pressure command is output from the CVT control unit 8 to the clutch / brake pressure solenoid valve 75.

  Therefore, in the clutch / brake pressure solenoid valve 75, the oil from the line pressure oil passage 711 is discharged via the line pressure port 75a → the drain port 75d. Further, the oil from the output pressure oil passage 712 is also discharged via the output pressure port 75b → the drain port 75d.

  On the other hand, when the spool 77f of the manual valve 77 is in the N range position shown in FIG. 5, the D range pressure port 77b and the forward drain port 77d are communicated, and the R range pressure port 77c and the reverse drain port 77e are communicated. The In the drain pressure solenoid valve 76, the drain pressure is adjusted to the drain pressure Pdr commanded by using the decompressed line pressure PL as the original pressure in accordance with the drain pressure command value output from the CVT control unit 8 regardless of the range position.

  Accordingly, the oil having the drain pressure Pdr from the drain pressure solenoid valve 76 is guided from the drain pressure oil passage 716 to the communication passage 723 and separated from the communication passage 723 in two directions. The oil having the drain pressure Pdr divided in one direction (the upper direction in FIG. 5) passes through the communication passage 723 via the forward drain oil passage 721 → the forward drain port 77d → the D range pressure port 77b → the D range pressure oil passage 719. Guided to the piston oil chamber of the forward clutch 31. The oil having the drain pressure Pdr divided in the other direction (the lower direction in FIG. 5) passes through the communication passage 723 via the reverse drain oil passage 722 → the reverse drain port 77e → the R range pressure port 77c → the R range pressure oil passage 720. Guided to the piston oil chamber of the reverse brake 32.

  Thus, when the N range position is selected, the D range pressure oil passage 719 and the piston oil chamber of the forward clutch 31, the R range pressure oil passage 720 and the piston oil chamber of the reverse brake 32 are drained in advance. The oil is filled with pressure Pdr.

(D range position: Fig. 6)
When the D range position is selected by the select lever 9, the spool 77f moves upward from the N range position shown in FIG. 5 to the D range position shown in FIG. For this reason, the input pressure port 77a and the D range pressure port 77b communicate with each other, and the communication between the input pressure port 77a and the R range pressure port 77c is blocked. When the D range position is selected, the forward clutch pressure command value is output from the CVT control unit 8 to the clutch / brake pressure solenoid valve 75.

  Therefore, in the clutch / brake pressure solenoid valve 75, the line pressure PL that defines the upper limit pressure from the line pressure oil passage 711 is used as the original pressure, and the pressure is adjusted to the commanded forward clutch pressure Pfc. The forward clutch pressure Pfc regulated by the clutch / brake pressure solenoid valve 75 passes through the output pressure oil passage 712 → the output pressure port 75 b → the D range pressure port 77 b → the D range pressure oil passage 719. The piston is guided to the oil chamber.

  On the other hand, when the spool 77f of the manual valve 77 is in the D range position shown in FIG. 6, the communication between the D range pressure port 77b and the forward drain port 77d is cut off, and the R range pressure port 77c and the reverse drain port 77e communicate. Is done. In the drain pressure solenoid valve 76, the drain pressure is adjusted to the drain pressure Pdr commanded by using the decompressed line pressure PL as the original pressure in accordance with the drain pressure command value output from the CVT control unit 8 regardless of the range position.

  Therefore, the oil of the drain pressure Pdr from the drain pressure solenoid valve 76 passes through the drain pressure oil passage 716 → the communication passage 723 → the reverse drain oil passage 722 → the reverse drain port 77e → the R range pressure port 77c → the R range pressure oil passage 720. Via, it is led to the piston oil chamber of the reverse brake 32.

  Thus, when the D range position is selected, the oil of the forward clutch pressure Pfc is supplied to the D range pressure oil passage 719 and the piston oil chamber of the forward clutch 31. At the same time, the piston oil chambers of the R range pressure oil passage 720 and the reverse brake 32 are filled with oil having a drain pressure Pdr in advance.

(R range position: Fig. 7)
When the R range position is selected by the select lever 9, the spool 77f moves downward from the N range position shown in FIG. 5 to the R range position shown in FIG. For this reason, the input pressure port 77a and the R range pressure port 77c are communicated, and the communication between the input pressure port 77a and the D range pressure port 77b is blocked. When the R range position is selected, a reverse brake pressure command value is output from the CVT control unit 8 to the clutch / brake pressure solenoid valve 75.

  Therefore, in the clutch / brake pressure solenoid valve 75, the line pressure PL defining the upper limit pressure from the line pressure oil passage 711 is used as the original pressure, and the pressure is adjusted to the commanded reverse brake pressure Prb. Then, the reverse brake pressure Prb regulated by the clutch / brake pressure solenoid valve 75 passes through the output pressure oil passage 712, the output pressure port 75b, the R range pressure port 77c, and the R range pressure oil passage 720. The piston is guided to the oil chamber.

  On the other hand, when the spool 77f of the manual valve 77 is in the R range position shown in FIG. 7, the communication between the R range pressure port 77c and the reverse drain port 77e is cut off, and the D range pressure port 77b and the forward drain port 77d are in communication. Is done. In the drain pressure solenoid valve 76, the drain pressure is adjusted to the drain pressure Pdr commanded by using the decompressed line pressure PL as the original pressure in accordance with the drain pressure command value output from the CVT control unit 8 regardless of the range position.

  Therefore, the oil having the drain pressure Pdr from the drain pressure solenoid valve 76 passes through the drain pressure oil passage 716 → the communication passage 723 → the forward drain oil passage 721 → the forward drain port 77d → the D range pressure port 77b → the D range pressure oil passage 719. Via, it is guided to the piston oil chamber of the forward clutch 31.

  As described above, when the R range position is selected, the oil of the reverse brake pressure Prb is supplied to the R range pressure oil passage 720 and the piston oil chamber of the reverse brake 32. At the same time, the D range pressure oil passage 719 and the piston oil chamber of the forward clutch 31 are filled with oil having a drain pressure Pdr in advance.

[Hydraulic control by selecting operation]
Hereinafter, based on FIGS. 5 to 7, the hydraulic control action by the D → R · R → D select operation, the N → D · N → R select operation, and the D → N · R → N select operation will be described.

(D → R ・ R → D select operation)
At the time of D → R selection operation performed in a parking scene or the like, the forward clutch 31 fastened on the selection side of the D range position shown in FIG. 6 is released, and is released on the selection side of the D range position shown in FIG. The reverse brake 32 is fastened. Then, it is necessary to shift to the state when the R range position shown in FIG. 7 is selected.

  While the D range position is selected, the oil of the high forward clutch pressure Pfc (> drain pressure Pdr) is supplied to the D range pressure oil passage 719 and the piston oil chamber of the forward clutch 31. Therefore, when the D → R selection operation is performed, the oil of the forward clutch pressure Pfc supplied to the piston oil chamber of the forward clutch 31 is discharged to the outside from the drain port 76d of the drain pressure solenoid valve 76, and the drain pressure Pdr ( ≒ Return pressure) That is, the oil of the forward clutch pressure Pfc is D range pressure oil passage 719 → D range pressure port 77b → forward side drain port 77d → forward side drain oil passage 721 → communication oil passage 723 → drain pressure oil passage 716 → drain pressure port. 76a → discharged to the outside via the drain port 76d. Therefore, the forward clutch 31 that is engaged at the D range position can be quickly released.

  On the other hand, while the D range position is selected, the R range pressure oil passage 720 and the piston oil chamber of the reverse brake 32 are filled with oil of the drain pressure Pdr in advance. Accordingly, when the D → R select operation is performed, the reverse brake pressure Prb adjusted in the clutch / brake pressure solenoid valve 75 is changed to the output pressure oil passage 712 → the output pressure port 75b → the R range pressure port 77c → the R range pressure oil. It is guided to the piston oil chamber of the reverse brake 32 via a path 720. Thus, when the reverse brake 32 that has been released at the D range position is engaged, since the oil of the drain pressure Pdr is filled in advance, the precharge phase in the engagement hydraulic pressure control can be eliminated. Therefore, the time required for engaging the reverse brake 32 is shortened by the time required for the precharge phase in the engagement hydraulic control, and the reverse brake 32 released at the D range position can be quickly engaged.

  In the R → D select operation, the reverse brake 32 engaged at the R range position can be quickly released and released at the R range position as in the D → R select operation. The forward clutch 31 can be quickly engaged.

(N → D ・ N → R select operation)
At the time of the N → D selection operation performed in the forward start scene, the forward clutch 31 released on the selection side of the N range position shown in FIG. 5 is engaged. Then, it is necessary to shift to the state when the D range position shown in FIG. 6 is selected.

  While the N range position is selected, the D range pressure oil passage 719 and the piston oil chamber of the forward clutch 31 are filled with oil of the drain pressure Pdr in advance. Therefore, when the N → D selection operation is performed, the forward clutch pressure Pfc adjusted in the clutch / brake pressure solenoid valve 75 is changed to the output pressure oil passage 712 → the output pressure port 75b → the D range pressure port 77b → the D range pressure oil. It is guided to the piston oil chamber of the forward clutch 31 via a path 719. In this way, when the forward clutch 31 that has been released at the N range position is engaged, the oil of the drain pressure Pdr is filled in advance, so that the precharge phase in the engagement hydraulic control can be eliminated. Therefore, the time required for the engagement of the forward clutch 31 is shortened by the time required for the precharge phase in the engagement hydraulic control, the forward clutch 31 released at the N range position is quickly engaged, and the start response to the forward side is achieved. Can be secured.

  In the N → R selection operation, the forward clutch 31 that has been released at the N range position can be quickly engaged and the start responsiveness to the reverse side can be ensured as in the N → D selection operation. it can.

(D → N ・ R → N select operation)
When the D → N selection operation is performed in a stop scene from the traveling state, the forward clutch 31 that is engaged on the selection side of the D range position shown in FIG. 6 is released. Then, it is necessary to shift to the state when the N range position shown in FIG. 5 is selected.

  When the D → N selection operation is performed, the oil of the forward clutch pressure Pfc supplied to the piston oil chamber of the forward clutch 31 and the D range pressure oil passage 719 is drained. That is, the oil of the forward clutch pressure Pfc passes through the D range pressure port 77b → the forward side drain port 77d → the forward side drain oil passage 721 → the communication oil passage 723 → the drain pressure oil passage 716 → the drain pressure port 76a → the drain port 76d. And discharged to the outside. At this time, since there is a communication oil passage 723 in the drain path, it goes from the communication oil passage 723 to the piston oil chamber of the reverse brake 32 via the reverse-side drain port 77e → R range pressure port 77b → R range pressure oil passage 720. Therefore, it is necessary to prevent the oil of the forward clutch pressure Pfc from being guided.

  On the other hand, the passage diameter L1 of the communication oil passage 723 is set smaller than the oil passage diameter L2 of the D range pressure oil passage 719 and the oil passage diameter L2 of the R range pressure oil passage 720, and the oil flowing through the communication oil passage 723 is reduced. The flow resistance is increased. For this reason, the oil from the D-range pressure oil passage 719 flowing into the communication oil passage 723 smoothly flows and is discharged to the drain pressure oil passage 716, and the oil flow to the reverse-side drain port 77e is suppressed. The As described above, when the D → N selection operation is performed, the forward clutch 31 is quickly released by suppressing the oil of the forward clutch pressure Pfc from flowing to the reverse brake 32 side. As a result, when the D → N selection operation is performed, the forward clutch 31 and the reverse brake 32 can shift to the N range state in which the release clutch is in a released state with good response.

  Even during the R → N selection operation, the reverse brake 32 is quickly released by preventing the reverse brake pressure Prb from flowing into the forward clutch 31 as in the D → N selection operation. Is done. As a result, at the time of R → N selection operation, the forward clutch 31 and the reverse brake 32 can shift to the N range state in which the release clutch is in a released state with good response.

  As described above, at the time of D → N selection operation or R → N selection operation, it is possible to shift to the N range state with good response. Therefore, even when a selection operation for returning to the original travel range position via the N range position, such as a D → N → D selection operation or an R → N → R selection operation, is performed, the forward clutch 31 or the reverse clutch The fastening response of the brake 32 can be ensured.

[Characteristic action of hydraulic control by switching range position]
In the first embodiment, a communication passage 723 that connects the forward drain oil passage 721 and the reverse drain oil passage 722 connected to the drain ports 77 d and 77 e of the manual valve 77 is provided, and a drain pressure solenoid valve 76 is provided in the communication passage 723. Provided. Regardless of the switching position of the manual valve 77, the drain pressure solenoid valve 76 maintains oil filling to the forward drain oil passage 721 and the reverse drain oil passage 722 via the communication passage 723.

  That is, when the present inventor performs a select operation to the travel range position, the oil to the frictional engagement element that is fastened by the select operation is in an oil drained state (oil path oil is empty) before the select operation. It has been found that fastening lugs and fastening shocks occur due to Since this oil drainage is caused by the oil being discharged through the manual valve 77, it is desired to abolish the manual valve 77 itself, but it cannot be abolished to prevent interlock.

  Paying attention to these points, a communication passage 723 that connects the forward drain oil passage 721 and the reverse drain oil passage 722 of the manual valve 77 is provided, and a drain pressure solenoid valve 76 as oil filling means is provided in the communication passage 723. . Accordingly, regardless of the switching position of the manual valve 77, oil filling to the forward drain oil passage 721 and the reverse drain oil passage 722 is maintained via the communication passage 723, and the fastening lug caused by oil leakage is maintained. And fastening shocks are reduced.

  Here, “maintenance of oil filling” does not mean the maintenance of a completely filled state in which the oil passage system has no oil omission space and is filled with oil. Even if the oil omission space exists, it is only necessary to maintain a state where oil is contained in the oil passage system.

  By the way, the reason why the fastening shock is reduced is that the oil path to the friction fastening element is filled with oil → the time until the hydraulic pressure rises → the time until the fastening increases → the inclination of the fastening hydraulic pressure is lowered This is due to the mechanism action of “can be → the angular acceleration of the turbine runner 24 is reduced → the inertia torque of the turbine runner 24 is reduced → the fluctuation torque at the time of fastening is reduced”.

  Therefore, when performing a selection operation to the travel range position, such as a D → R selection operation, an R → D selection operation, an N → D selection operation, an N → R selection operation, etc., the forward clutch 31 that is engaged by the selection operation. And the fastening lug and fastening shock of the reverse brake 32 are reduced.

  In Example 1, the flow resistance when oil flows through the communication path 723 is set larger than the flow resistance when oil flows through the D range pressure oil path 719 and the R range pressure oil path 720.

  That is, when a selection operation is performed from the travel range position (D range position, R range position) to the N range position, the high-pressure oil on the fastening side is prevented from flowing to the release side via the communication path 723.

  Therefore, when a selection operation (D → N selection operation, R → N selection operation) from the travel range position to the N range position is performed, the N range state in which both the forward clutch 31 and the reverse brake 32 are in a released state is responsive. Migrated. Furthermore, even when a select operation (D → N → D select operation, R → N → R select operation) for returning to the original travel range position via the N range position is performed, the engagement response of the friction engagement element is Secured.

  In the first embodiment, the oil filling means is the drain pressure solenoid valve 76 capable of controlling the drain pressure Pdr within a hydraulic pressure range where no transmission torque is generated in the forward clutch 31 and the reverse brake 32.

  In other words, the drain pressure solenoid valve 76 can control the drain pressure Pdr, which is the release pressure from the friction engagement element, within the range of zero pressure to return pressure. Therefore, the degree of freedom of control of the drain pressure Pdr, which is the release pressure from the frictional engagement element, is increased.

  For example, in a situation where the oil drain response is delayed, for example, the drain shock can be improved by reducing the drain pressure Pdr from the return pressure level to the zero pressure side. It is also possible to perform drain pressure Pdr switching control and adjustment control according to the oil temperature at which the oil viscosity changes. Furthermore, when the return pressure varies depending on the frictional engagement element, the drain pressure Pdr can be controlled according to the different return pressure.

  In the first embodiment, the drain pressure solenoid valve 76 serving as oil filling means is provided at a position in the middle of the communication passage 723 in the oil passage length direction.

  That is, the oil path length from the drain pressure solenoid valve 76 to the forward drain oil path 721 and the oil path length from the drain pressure solenoid valve 76 to the reverse drain oil path 722 are substantially the same length. For this reason, when the drain pressure Pdr is regulated by the drain pressure solenoid valve 76 based on the generation of the pump discharge pressure, the regulated drain pressure Pdr oil and the forward drain oil passage 721 and the reverse drain are responsive at substantially the same timing. Both oil passages 722 are filled. Since the oil pump 70 according to the first embodiment is driven to rotate by the engine 1, no pump discharge pressure is generated while the engine 1 is stopped, and a pump discharge pressure is generated when the engine 1 is started.

Next, the effect will be described.
In the hydraulic control device for the belt type continuously variable transmission according to the first embodiment, the following effects can be obtained.

(1) Hydraulic source (oil pump 70), manual valve 77, forward friction engagement element (forward clutch 31), reverse friction engagement element (reverse brake 32), forward drain oil passage 721, reverse drain oil passage 722.
The manual valve 77 switches the supply destination of the oil supplied from the hydraulic pressure source (oil pump 70) according to the selection operation to the select lever 9.
The forward friction engagement element (forward clutch 31) is engaged when the select lever 9 selects the forward range position (D range position).
The reverse friction engagement element (reverse brake 32) is engaged when the select lever 9 selects the reverse range position (R range position).
The forward drain oil passage 721 drains oil to the forward frictional engagement element (forward clutch 31).
The reverse drain oil passage 722 drains oil to the reverse friction engagement element (reverse brake 32).
In the hydraulic control device of this automatic transmission (belt type continuously variable transmission), a communication passage 723 that connects the forward drain oil passage 721 and the reverse drain oil passage 722 connected to the drain ports 77d and 77e of the manual valve 77 is provided. At the same time, an oil filling means (drain pressure solenoid valve 76) is provided in the communication passage 723.
The oil filling means (drain pressure solenoid valve 76) maintains oil filling to the forward drain oil passage 721 and the reverse drain oil passage 722 via the communication passage 723 regardless of the switching position of the manual valve 77.
For this reason, when performing the selection operation to the travel range position (D, R range position), it is possible to reduce the engagement lug and engagement shock of the friction engagement elements (forward clutch 31 and reverse brake 32) that are engaged by the selection operation. it can.

(2) The forward pressure supply oil passage (D-range pressure oil passage 719) connecting the manual valve 77 and the forward friction engagement element (forward clutch 31), and the manual valve 77 and the reverse friction engagement element (reverse brake 32) are connected. A reverse pressure supply oil passage (R range pressure oil passage 720).
The flow resistance when oil flows through the communication passage 723 is larger than the flow resistance when oil flows through the forward pressure supply oil passage (D range pressure oil passage 719) and the reverse pressure supply oil passage (R range pressure oil passage 720). Set.
For this reason, in addition to the effect of (1), at the time of the selection operation from the traveling range position (D, R range position) to the N range position, it is possible to shift to the N range state with good response. In addition, at the time of a selection operation for returning to the original travel range position via the N range position (D, R range position), it is possible to ensure the engagement response of the friction engagement elements (forward clutch 31, reverse brake 32). .

(3) The oil filling means is a drain pressure solenoid valve capable of controlling the drain pressure Pdr within a hydraulic pressure range in which no transmission torque capacity is generated in the forward friction engagement element (forward clutch 31) and the reverse friction engagement element (reverse brake 32). 76.
For this reason, in addition to the effect of (1) or (2), the drain pressure solenoid valve 76 is used as the oil filling means, so that the drain pressure that is the release pressure from the frictional engagement elements (forward clutch 31 and reverse brake 32). The degree of freedom of control of Pdr can be increased.

(4) The oil filling means (drain pressure solenoid valve 76) is provided at a middle position with respect to the oil passage length direction of the communication passage 723.
Therefore, in addition to the effects of (1) to (3), when the oil from the oil filling means (drain pressure solenoid valve 76) is filled into the forward drain oil passage 721 and the reverse drain oil passage 722, the response is made at almost the same timing. Both oil passages 721 and 722 can be filled well.

  Example 2 is an example in which the oil filling means is provided in a position closer to the forward drain oil passage than to the reverse drain oil passage in the communication passage.

  FIG. 8 shows a main part of the hydraulic control circuit 71 including the manual valve 77 of the second embodiment. The hydraulic control circuit configuration will be described below with reference to FIG. Since the system configuration is the same as that of FIG. 1 of the first embodiment, the illustration and description are omitted.

  As shown in FIG. 8, the hydraulic control circuit 71 included in the hydraulic control unit 7 includes a clutch / brake pressure solenoid valve 75, a drain pressure solenoid valve 76 (oil filling means), and a manual valve 77. Since the clutch / brake pressure solenoid valve 75, the drain pressure solenoid valve 76, and the manual valve 77 are the same as those in the first embodiment, the description thereof is omitted.

  The end of the forward drain oil passage 721 and the end of the reverse drain oil passage 722 are connected by a communication passage 723 ′ that communicates both the oil passages 721 and 722. The passage diameter of the communication passage 723 ′ is the same as the oil passage diameter of the D-range pressure oil passage 719 and the oil passage diameter of the R-range pressure oil passage 720, but the communication passage 723 ′ has an orifice that gives flow resistance to the flowing oil. 724 is set. A drain pressure oil passage 716 from the drain pressure solenoid valve 76 is connected to a position communicating with the forward side drain port 77 d of the manual valve 77.

Next, the operation of the second embodiment will be described.
In the second embodiment, the drain pressure solenoid valve 76 as oil filling means is provided in a position closer to the forward drain oil passage 721 than the reverse drain oil passage 722 in the communication passage 723 ′.

That is, the driver feels that the engagement lag of the forward clutch 31 when the D range position is selected is more uncomfortable than the engagement lag of the reverse brake 32 when the R range position is selected. Therefore, the drain pressure solenoid valve 76 as oil filling means is provided at a position close to the forward drain oil passage 721. Thereby, the oil of the drain pressure Pdr from the drain pressure solenoid valve 76 is supplied with priority to the forward clutch 31 side rather than the reverse brake 32 side via the communication oil passage 723 ′ having a large flow resistance. Accordingly, when the N → D selection operation or the R → D selection operation is performed, the oil having the drain pressure Pdr can be preferentially supplied to the D range pressure oil passage 719 to the forward clutch 31 before the selection operation. As a result, at the time of the selection operation for selecting the D range position, the engagement response from the selection operation until the forward clutch 31 is in the engagement state is further improved.
Since other operations are the same as those of the first embodiment, description thereof is omitted.

Next, the effect will be described.
In the hydraulic control device for the belt type continuously variable transmission according to the second embodiment, the following effects can be obtained.

(5) The oil filling means (drain pressure solenoid valve 76) is provided in the communication path 723 ′ at a position closer to the forward drain oil path 721 than to the reverse drain oil path 722.
For this reason, in addition to the effects of (1) to (3), during the selection operation for selecting the forward range position (D range position), the engagement from the selection operation until the forward frictional engagement element (forward clutch 31) is in the engaged state. Responsiveness can be further improved.

  As described above, the hydraulic control device for an automatic transmission according to the present invention has been described based on the first and second embodiments. However, the specific configuration is not limited to these examples, and design changes and additions are permitted without departing from the spirit of the invention according to each claim of the claims.

  In the first and second embodiments, an example in which the drain pressure solenoid valve 76 capable of controlling the drain pressure Pdr within a hydraulic pressure range where no transmission torque capacity is generated in the forward clutch 31 and the reverse brake 32 is used as the oil filling means. However, the oil filling means may be an example using an accumulator, an electric oil pump, a solenoid valve for regulating the oil pump pressure, or the like.

  In the first embodiment, an example in which flow resistance is given to the flowing oil by reducing the oil passage diameter of the communication path 723, and in the second embodiment, the flow resistance to the flowing oil is provided by providing the orifice 724 in the communication path 723 ′. An example that gives However, the configuration for giving flow resistance to the oil flowing through the communication passage may be a combination configuration of a small-diameter oil passage and an orifice, or an example in which the flow resistance can be changed by a variable orifice.

  In the first and second embodiments, an example in which a clutch / brake pressure solenoid valve 75 that also serves as two valves is provided as an engagement pressure control valve upstream of the manual valve 77 on the hydraulic power source side is shown. However, the engagement pressure control valve may be an example in which a clutch pressure solenoid valve and a brake pressure solenoid valve are provided in each of the D range pressure oil passage and the R range pressure oil passage downstream of the manual valve.

  In the first and second embodiments, an example in which the oil pump 70 that is rotationally driven by the engine 1 is used as the hydraulic pressure source is shown. However, as the hydraulic power source, a mechanical oil pump that is rotationally driven by an engine and an electric oil pump that is rotationally driven by an electric motor may be used in combination.

  In the first and second embodiments, the hydraulic control device of the present invention is applied to an engine vehicle equipped with a belt type continuously variable transmission. However, the hydraulic control device of the present invention can also be applied to a vehicle equipped with a stepped transmission having a plurality of shift stages as an automatic transmission. Furthermore, the vehicle is not limited to an engine vehicle, and can be applied to a hybrid vehicle or an electric vehicle equipped with an automatic transmission (belt type continuously variable transmission or stepped transmission).

DESCRIPTION OF SYMBOLS 1 Engine 2 Torque converter 3 Forward / reverse switching mechanism 31 Forward clutch (forward friction fastening element)
32 Reverse brake (reverse friction engagement element)
4 Variator (automatic transmission)
7 Hydraulic control unit 70 Oil pump (hydraulic power source)
71 Hydraulic control circuit 716 Drain pressure oil passage 719 D range pressure oil passage (forward pressure supply oil passage)
720 R range pressure oil passage (reverse pressure supply oil passage)
721 Forward drain oil passage 722 Reverse drain oil passage 723 Communication passage 723 'Communication passage 724 Orifice 75 Clutch / brake pressure solenoid valve 76 Drain pressure solenoid valve (oil filling means)
77 Manual valve 77a Input pressure port 77b D range pressure port 77c R range pressure port 77d Forward drain port 77e Reverse drain port 77f Spool 8 CVT control unit 9 Select lever

Claims (5)

A hydraulic source;
A manual valve that switches the supply destination of oil supplied from the hydraulic pressure source according to a selection operation to the select lever;
A forward friction fastening element that is fastened when the select lever is selected in the forward range position;
A reverse friction engagement element that is engaged when the select lever is selected in a reverse range position;
A forward drain oil passage for draining oil to the forward frictional engagement element;
A reverse drain oil passage for draining oil to the reverse friction engagement element, and a hydraulic control device for an automatic transmission comprising:
Providing a communication passage for communicating the forward drain oil passage connected to the drain port of the manual valve and the reverse drain oil passage, and providing oil filling means in the communication passage;
The oil filling means maintains oil filling to the forward drain oil passage and the reverse drain oil passage through the communication passage regardless of the manual valve switching position. Hydraulic control device. The hydraulic control device for an automatic transmission according to claim 1,
A forward pressure supply oil path connecting the manual valve and the forward frictional engagement element, and a reverse pressure supply oil path connecting the manual valve and the reverse frictional engagement element,
A hydraulic control device for an automatic transmission, wherein a flow resistance when oil flows through the communication path is set to be larger than a flow resistance when oil flows through the forward pressure supply oil passage or the reverse pressure supply oil passage. . In the hydraulic control device for an automatic transmission according to claim 1 or 2,
The oil filling means is a drain pressure solenoid valve capable of controlling a drain pressure within a hydraulic pressure range in which a transmission torque capacity is not generated in the forward friction engagement element and the reverse friction engagement element. Hydraulic control device. In the automatic transmission hydraulic control device according to any one of claims 1 to 3,
The hydraulic control device for an automatic transmission, wherein the oil filling means is provided at a position of an intermediate portion with respect to the oil passage length direction of the communication passage. In the automatic transmission hydraulic control device according to any one of claims 1 to 3,
The hydraulic control device for an automatic transmission, wherein the oil filling means is provided in a position closer to the forward drain oil passage than to the reverse drain oil passage in the communication passage.