JP2002039344A - Hydraulic control device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To select a selector valve changing over between a control pressure and an operating pressure (range pressure) in starting without using a dedicated solenoid valve. SOLUTION: A ratio control valve 80 is changed over in respective positions of feed, discharge, and cutoff by a downshift solenoid valve S3 and an upshift solenoid valve S4 so as to control the shifting. Where the two solenoid valves S3 and S4 become three types of combinations controlling the shifting, the selector valve 79 is in a direct position to feed operating pressure PB1 and PC1. When the two solenoid valves S3 and S4 are combination except for the three types of combinations, the selector valve 79 is in a control position to feed a control pressure PCC.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control device for an automatic transmission used in a vehicle such as an automobile, and more particularly to a hydraulic control device having a control valve controlled by two solenoid valves such as a ratio control valve. More specifically, the present invention relates to a hydraulic control device that switches a hydraulic pressure for a frictional engagement element that is engaged at the time of starting to a control pressure and an operating (range) pressure.

[0002]

2. Description of the Related Art Conventionally, a friction engagement element which is engaged at the time of starting is provided.
For example, as a hydraulic control device for switching a hydraulic pressure for a direct (input) clutch between a control pressure and an operating pressure (range pressure), there is one disclosed in, for example, JP-A-10-246317. This is equipped with a neutral relay valve that is switched by a solenoid valve, and a control valve that is pressure-controlled by a linear solenoid valve,
When the manual shift valve is switched from the neutral range to the drive range (N → D), the control pressure regulated by the control valve is supplied to the direct clutch hydraulic servo through a predetermined port of the neutral relay valve, The control pressure is gradually increased, the direct clutch is smoothly engaged, and the neutral relay valve is switched to shut off the control pressure and supply the range pressure from the manual shift valve to the hydraulic servo. Thus, the direct clutch is held in the engaged state.

[0003]

The above-described solenoid valve according to the prior art switches the neutral relay valve and also switches the reverse inhibit valve as described above. This is because the neutral relay valve and the reverse inhibit valve are switched. It takes advantage of the fact that it does not operate at the same time, and has a design that lacks flexibility. That is, when the reverse inhibit function is performed by using another switching valve such as a lock-up relay valve and not using a dedicated switching valve, or not only when the vehicle is moving forward but also when the vehicle is moving backward, that is, from the neutral range to the reverse range (N → R). When the control pressure and the range pressure are also switched at the time of the switching of ()), a dedicated solenoid valve is required for each.

In view of the above, the present invention solves the above-mentioned problems by performing a switching valve for switching hydraulic pressure to a hydraulic servo for a frictional engagement element, which is engaged at the time of starting, between control pressure and operating pressure without using a dedicated solenoid. It is an object of the present invention to provide a hydraulic control device for an automatic transmission.

[0005]

The present invention according to claim 1 (see, for example, FIGS. 2 and 7) has two solenoid valves (S3, S4) and a signal pressure from these two solenoid valves. A control valve (80) that switches the output port (80i) to three types of a supply position, a discharge position, and a shutoff position according to the combination; a hydraulic servo (B1, C1) for a frictional engagement element that engages when starting; The hydraulic pressure supplied to the hydraulic servo is adjusted to the operating pressure (PB1, PC
1) and a switching valve (79) for switching between a smoothly connected control pressure (PCC), and a combination of the two solenoid valves (S3, S4) other than the three types of switching of the control valve. The switching valve (79)
In the hydraulic control device of the automatic transmission.

According to a second aspect of the present invention (see, for example, FIGS. 1 and 7), the control valve (80) upshifts the continuously variable transmission (2) at the supply position and at the discharge position. 2. The hydraulic control device for an automatic transmission according to claim 1, wherein the shift control valve is a shift control valve (ratio control valve) that controls to shift down and hold at the shutoff position. 3.

According to a third aspect of the present invention (see, for example, FIGS. 8, 9 and 10), the switching valve (79, 79 ₁ ,
79 ₂ ) is the hydraulic control device for an automatic transmission according to claim 1 or 2, wherein the switching is performed according to a combination of the case where the two solenoid valves output the signal pressure together with the other combination.

The present invention according to claim 4 (for example, see FIGS. 8, 9, and 10), wherein the control valve (80)
One of the solenoid valves (S3) outputs the signal pressure and the other (S4) takes the discharge position when discharging, the other (S4) outputs the signal pressure and the other (S4) outputs the signal pressure.
3) takes the supply position when discharging takes the blocking position when the two solenoid valves (S3) (S4) is discharged together said switching valve (79, 79 _1,
79 _2), said when the said three positions said outputs an operation pressure at the time of the combination of the two solenoid valves take the (direct position), the two solenoid valves to output together signal pressure The hydraulic control device for an automatic transmission according to claim 3, wherein the hydraulic pressure control device takes a position (control position) for outputting a control pressure.

The present invention according to claim 5 (for example, FIG.
12, 13 and 14), the switching valve (7
9. The automatic transmission according to claim 1, wherein the switches 9 ₃ , 79 ₄ , 79 ₅ , and 79 ₆ ) are switched depending on whether the two solenoid valves (S <b> 3, S <b> 4) discharge together or a combination other than the two. In the hydraulic control unit of the machine.

The present invention according to claim 6 (for example, FIG.
12, 13, and 14) and the control valve (8
0) takes the discharge position when one of the two solenoid valves (S3) outputs a signal pressure and the other (S4) discharges, the other (S4) outputs a signal pressure and (S3) takes the supply position when discharging,
Taking the blocking position when the two solenoid outputs together signal pressure, the switching valve (79 3, _{79 4,} 7
9 _5, 79 _6), the two solenoid valves (S
(3) The position where the operating pressure is output (direct position) at the time of the combination of the three types (S4), and the position (control position) where the control pressure is output when the two solenoid valves discharge together. The hydraulic control device for an automatic transmission according to claim 5, wherein

According to a seventh aspect of the present invention (see FIGS. 8 and 11, for example), the switching valves (79 ₁ , 79 ₃ )
The control oil chamber (79) communicating with the output ports (e, f) of the two solenoid valves (S3, S4) arranged to bias the spool (79g) in one direction.
e, 79f), and a spring (79c) arranged to bias the spool in the other direction. The hydraulic control device for an automatic transmission according to any one of claims 3 to 6, further comprising:

According to an eighth aspect of the present invention (see, for example, FIGS. 9 and 13), the switching valve (79, 79 ₅ ) is disposed so as to bias the spool (79f) in one direction. The control oil chamber (79) communicating with the output ports (e, f) of the two solenoid valves (S3, S4), respectively.
e, 79f) and a control oil chamber (79h) communicating with the input ports (p, o) of the solenoid valves (S3, S4) arranged to bias the spool in the other direction.
The hydraulic control device for an automatic transmission according to any one of claims 3 to 6, further comprising:

The present invention according to claim 9 (for example, FIG.
13), the switching valve (79 ₄ , 79 ₅ )
Is an output port (e or f) of one of the two solenoid valves (S3 or S4) that urges one end of the plug, a spool (79f), a plug (79j) that can be brought into contact with and separated from the spool. Control oil chamber (79e or 7
9f) and the other of the two solenoid valves (S4 or S4) acting between the other end of the plug and the spool.
The control oil chamber (7) communicating with the output port (f or e) of 3)
9f or 79e). The hydraulic control device for an automatic transmission according to claim 5 or 6, further comprising:

The present invention according to claim 10 (for example, FIG.
), An input port (90a, 90b) communicating with an output port (e, f) of each of the two solenoid valves (S3, S4), an output port (90c), and one of the input ports. A switching mechanism (90d) for switching pressure so as to output pressure to an output port; and a selector valve (90) having the switching valve (79 ₆ ).
Are input ports (p, o) of the solenoid valve arranged to bias the spool (79g) in one direction.
A control oil chamber (79h) communicating with the control valve, and the selection valve (9) disposed to bias the spool in the other direction.
0) of the control oil chamber (79) communicating with the output port (90c).
7) The hydraulic control device for an automatic transmission according to claim 5, comprising: k).

The present invention according to claim 11 (for example, FIG.
See FIG. 2), the frictional engagement element hydraulic servo for engaging at the start of the vehicle, the friction engagement elements and the frictional engagement element to be engaged during forward (C ₁₎ for the hydraulic servo (C1), to engage during reverse travel (B ₁₎ a hydraulic servo (B1) for, in a hydraulic control device for an automatic transmission according to any one of claims 1 to 10.

The present invention according to claim 12 (for example, FIG.
7), a manual shift valve (75) operated by a driver, and an operating pressure (PB1, PC1) output from the switching valve (79) or control is input to an input port (PM) of the manual shift valve. The hydraulic control device for an automatic transmission according to claim 11, wherein the hydraulic control device is arranged to supply a pressure (PCC).

[Operation] Based on the above configuration, the control valve (80) is switched to the supply position, the discharge position, and the shut-off position by three combinations of the two solenoid valves (S3, S4). For example, one of two solenoid valves (S
When 3) outputs the signal pressure, the shift control valve (80) is in the discharge position and is in the downshift, and when the (S4) outputs the signal pressure, the shift control valve (80) is in the supply position and is in the upshift, both (S3, S4). ) Outputs or discharges the signal pressure together, and then enters the cutoff position to hold the transmission ratio. Thereby, the continuously variable transmission (2) is appropriately shifted to allow the vehicle to travel.

The above-mentioned two solenoid valves (S3, S3)
The control valve (80) is controlled by the combination of S4).
At this time, the switching valves (79...)
1), the frictional engagement element (B₁, C
₁) Is securely fastened. And the driver
Ralrange (N) to drive range (D) or river
When starting the vehicle by operating the Srange (R),
Solenoid valves (S3, S4) are the above three combinations
The remaining one other than the set, for example, both solenoid valves
Take position to discharge or supply signal pressure. This allows
The switching valve (79 ...) outputs the control pressure (PCC)
And the friction engagement element (B ₁, C₁) Is Xu
Connect to each other to start the vehicle smoothly. And the above
When the smooth engagement of the friction engagement element is completed, the solenoid
The valve (S3, S4) is one of the above three combinations
And the speed of the continuously variable transmission is changed
Replacement valve (79 ...) switches to a state where the operating pressure is output
Is held.

Note that the reference numerals in parentheses are for the purpose of comparison with the drawings, but are for convenience of understanding of the invention, and are not limited to the structure of the claims. It has no effect.

[0020]

According to the first aspect of the present invention, a control valve which switches to supply, discharge and shutoff positions by a combination of two solenoid valves is provided.
The switching valve is switched to the operating pressure or control pressure supply state by the combination of the remaining two solenoid valves, so that the engagement of the friction engagement element at the time of starting is smooth and the friction engagement element is switched. , The solenoid valve dedicated to the switching valve is not required.

According to the second aspect of the present invention, since the control valve is a shift control valve for controlling the continuously variable transmission, there is no need for shifting control when starting, and no starting control is necessary during shifting control. Therefore, start control and shift control can be performed without adversely affecting each other.

According to the present invention according to claims 3 and 4, 2
The switching valves are switched between the state in which both solenoid valves output signal pressure and the other combinations, so if the upshift is performed after the start control that supplies the control pressure, the signal pressure output state of both solenoid valves , It is only necessary to switch one of them to discharge, and it is possible to quickly and reliably switch to the normal driving control.

According to the fifth and sixth aspects of the present invention, 2
Since the switching valves are switched between a state in which the solenoid valves are both discharged and a combination other than that, when starting from an engine stopped state, the switching valves are in a low control pressure supply position due to the discharge state of both solenoid valves, Control at the time of starting by a quick rise can be performed.

According to the seventh aspect of the present invention, the control oil chambers communicating with the output ports of the two solenoid valves, respectively, start with the signal pressure being supplied or discharged, and then the resistance to the spring is reduced. Then the spool switches,
The switching bubble can be switched with a simple configuration.

According to the present invention, since the signal pressure of one solenoid valve is canceled by the hydraulic pressure (solenoid base pressure) communicating with the input port of the solenoid valve, the input pressure to the solenoid valve is reduced. Even if it changes, it is possible to always obtain constant switching start pressure and completion pressure of the switching valve (see, for example, FIG. 9B), and to reliably and accurately switch the switching valve irrespective of the oil pressure change due to the vehicle running condition. Can be switched. Further, by making the switching oil pressure of the switching valve proportional to the input pressure to the solenoid valve (for example, see FIG. 10B), even if the solenoid source pressure fluctuates, the switching valve can be switched reliably and accurately. .

According to the ninth aspect of the present invention, the control oil pressure acting between the spool and the plug is communicated with the output port of one of the solenoid valves, and the signal pressures from the two solenoid valves are individually applied to the spool. Since it operates, a simple and small switching valve using a spool and a plug having the same diameter can be used.

According to the tenth aspect of the present invention, since the signal pressure of both solenoid valves is supplied through the selection valve, one control oil chamber communicating with the output port of the solenoid valve of the switching valve is sufficient. Thus, the structure can be simplified and reduced in size.

According to the eleventh aspect of the present invention, at the time of starting both from the neutral position to the forward position and the reverse position, start control for supplying control pressure can be performed.

According to the twelfth aspect of the present invention, since the operating pressure or the control pressure output from the switching valve is supplied to the input port of the manual valve, control for both forward and reverse starting can be shared. Can be.

[0030]

FIG. 1 is a diagram showing a continuously variable automatic transmission 1 for a vehicle to which the present invention can be applied. The continuously variable automatic transmission includes a belt-type continuously variable transmission (CVT) 2, The vehicle includes a forward / reverse switching device 3, a torque converter 6 having a built-in lock-up clutch 5, a counter shaft 7, and a differential device 9, and these devices are housed in an integrated divided case.

[0031] The torque converter 6 is provided with the engine output shaft 1.
0, a pump impeller 11 connected via a front cover 17, a turbine runner 13 connected to an input shaft 12, and a stator 16 supported via a one-way clutch 15. The lock-up clutch 5 is interposed between the front cover 17 and the front cover 17. In the drawing, reference numeral 20 denotes a damper spring interposed between the lock-up clutch plate and the input shaft,
An oil pump 21 is connected to and driven by the pump impeller 11.

The CVT (belt type continuously variable transmission) 2 includes a fixed sheave 23 fixed to a primary shaft 22 and a movable sheave 2 supported only slidably on the shaft.
5, a secondary pulley 31 comprising a fixed sheave 29 fixed to a secondary shaft 27 and a movable sheave 30 supported only slidably on the shaft, and a primary pulley 26 wound around these pulleys. And a metal belt 32.

Further, a hydraulic actuator 33 composed of a double piston is disposed on the back of the primary movable sheave 25, and a hydraulic actuator 3 composed of a single piston is disposed on the rear of the secondary movable sheave 30.
5 are arranged. The primary hydraulic actuator 33 includes a cylinder member 36 and a reaction force support member 37 fixed to the primary shaft 22, and a movable sheave 25.
And a first hydraulic chamber 41 is formed on the back surface of the cylindrical member 39, the reaction force support member 37, and the movable sheave 25,
The second hydraulic chamber 42 is constituted by the cylinder member 36 and the piston member 40. The first hydraulic chamber 41 and the second hydraulic chamber 42 communicate with each other through a communication hole 37a, and generate an axial force substantially doubled as compared with the secondary hydraulic actuator 35 by the same hydraulic pressure. I do. on the other hand,
The secondary-side hydraulic actuator 35 has a reaction force support member 43 fixed to the secondary shaft 27 and a tubular member 45 fixed to the back of the movable sheave 30. These two members constitute one hydraulic chamber. A preload spring 47 is contracted between the movable sheave 30 and the reaction force support member 43.

The forward-reverse switching mechanism 3, a double-pinion planetary gear 50, and a reverse (reverse) brake B ₁ and the direct clutch (forward clutch or input clutch) C _1. The planetary gear 50 has a sun gear S connected to the input shaft 12, a carrier CR that supports the first and second pinions P ₁ and P ₂ connected to the primary fixed sheave 23, and a ring gear R. There is connected to the reverse brake B ₁ which is a reverse friction engagement element and said between the carrier CR and the ring gear R direct clutch C ₁ is interposed.

A large gear 51 and a small gear 52 are fixed to the counter shaft 7. The large gear 51 meshes with a gear 53 fixed to the secondary shaft 27, and the small gear 52 is a gear 55 of the differential device 9. Is engaged. The differential device 9 is configured such that rotation of a differential gear 56 supported by a differential case 66 having the gear 55 is controlled by left and right axles 60, 6 via left and right side gears 57, 59.
1 is transmitted.

Next, the hydraulic circuit of the continuously variable automatic transmission will be described with reference to FIG. In the figure, 21 is the oil pump, 70 is a primary regulator valve, 71 is a secondary regulator valve, SLT is a linear solenoid valve for controlling line pressure, 73 is a secondary sheave control valve, and 75 is a driver's shift lever or the like. This is a manual shift valve that is switched by operation.

Reference numeral 76 denotes the direct clutch C
₁ and supplied to the hydraulic servo C1, B1 for reverse brake B _1, a so-called clutch (modulator) pressure (working pressure, range pressure) clutch modulator valve that generates, 77, supplied to the hydraulic servo at the time of switching the clutch and brake A control valve 79 for generating a control pressure (control pressure), and a relay (switching) valve 79 for switching the clutch pressure and the control pressure.
Since the control valve and the relay valve are mainly used for garage opening and garage entry, 77 is referred to as a garage shift control valve, and 79 is referred to as a garage shift valve for convenience.

Reference numeral 80 denotes a ratio control valve (shift control valve), 81 denotes a lock-up relay valve, 82 denotes a lock-up control valve, and 83 denotes a solenoid modulator valve. And S1 is
This is a solenoid valve for switching the lock-up relay valve 81, and controls ON / OFF (supply / release) of a hydraulic pressure in a normally closed type. S2 is a solenoid valve that controls the lock-up control valve 81, and adjusts the hydraulic pressure by duty control in a normally closed type. S3 is a solenoid valve that operates the ratio control valve 80 on the downshift side and performs duty control in a normally closed type. S4 is a solenoid valve that operates the ratio control bubble on the upshift side. Duty control is performed with the normally closed type.

Further, in FIG. 2, 85 is a strainer, 86 is a relief valve, 87 is an oil temperature sensor, 89 is a pressure sensor, 90 is a lubricating oil passage, 91 is a cooler, 92 is a cooler bypass valve, and 93 is a check valve. As described above, 33 is a primary hydraulic actuator, 35 is a secondary hydraulic actuator, 6 is a torque converter, and 5 is a lock-up clutch. In FIG. 2, the other parts follow the well-known hydraulic symbols.

Next, the operation based on the above configuration will be described. A predetermined hydraulic pressure is generated by the rotation of the oil pump 21 based on the engine rotation. As shown in FIG. 4, the hydraulic pressure is controlled by a signal from a control unit that is calculated based on a pulley ratio and an input torque. S
By controlling the primary regulator valve 70 based on the SLT (control) pressure from the LT, the line pressure P
L and the secondary regulator valve 71
Thereby, the secondary pressure (Psec) is adjusted. Further, the signal oil pressure (SLT pressure) from the output port a of the linear solenoid valve SLT is supplied to the control oil chamber 73a of the secondary sheave control valve 73 via the oil passage a1, and the valve 73 is input to the port 73b. The secondary line pressure is adjusted to the secondary sheave pressure PSS, output to the port 73c, and supplied to the secondary hydraulic actuator 35.

Further, the linear solenoid valve SLT
Is supplied to the control oil chamber 77a of the garage control valve 77 via the oil passage a2,
The valve 77 adjusts the clutch pressure input to the port 77b to the clutch control pressure PCC and outputs the adjusted pressure from the port 77c.

The clutch modulator valve 76
The line pressure PL is input to the port 76a,
6b, the output pressure (clutch pressure) from the output port is input to one control oil chamber 76c, and the spool is urged toward the control oil chamber by a spring 76d. A manual shift valve 75 is connected to the other control oil chamber 76e via a small-diameter plug.
From the reverse port R is supplied through the oil passage b. Therefore, the clutch modulator valve 76
As shown in FIG. 5, when the line pressure PL is low,
The feedback pressure acting on the control oil chamber 76c outputs the clutch pressure substantially equal to the line pressure in the left half position without overcoming the preload of the spring 76d. However, when the line pressure PL increases, the feedback pressure corresponding thereto increases. When the feedback pressure also increases and overcomes the preload of the spring 76d, a substantially constant clutch pressure PB1, PC1 is obtained due to the balance between the spring 76d and the feedback pressure of the control oil chamber 76c.
Output.

Here, when the manual shift valve 75 is
In the range, the hydraulic pressure from the reverse port R acts on the lower end control oil chamber 76e to assist the lifting force of the spool, and the clutch pressure from the output port 76b causes no hydraulic pressure to act on the control oil chamber. It becomes higher by a predetermined amount than the D range pressure. Accordingly, in FIG. 5, the clutch pressure PB1 in the reverse range (R) acting on the hydraulic servo B1 is changed to the hydraulic servo C1.
1 is set to be higher than the clutch pressure PC1 in the forward range (D) by a predetermined amount, and the clutch (brake) engaging force is set to correspond to the output torque.

Next, the operation of the continuously variable automatic transmission will be described with reference to the operation table shown in FIG. When the vehicle is in the parking range P, the reverse range R, and the neutral range N, 4
All the solenoid valves S1 to S4 are OFF and are in a released state. Also, the clutch pressure from the output port 76b of the clutch modulator valve 76 is
1, through the strainer 85 and the oil passage c2, the ports 79a, 7 of the garage shift valve 79 at the further right half position.
9b is supplied to the input (supply) port PM of the manual shift valve 75. The oil passage c2
Is input to the input port c of the linear solenoid valve SLT and is also input to the solenoid modulator valve 83. The modulator valve 83 reduces the clutch pressure by a predetermined amount and supplies the clutch pressure to the solenoid valves S1 to S4 and the control oil chamber 79c of the garage shift valve 79.

In the drive range D, the manual shift valve 75 communicates the input port PM with the drive port D, and the clutch pressure is supplied to the hydraulic servo C1 via the oil passage d. Clutch C
To connect the _1. In this state, the rotation of the engine output shaft 10, the torque converter 6 is transmitted through the input shaft 12 and the planetary gear 50 which is directly coupled by the direct clutch C ₁ to the primary pulley 26, a CVT2 be further appropriately shift Through the secondary shaft 2
7 and transmitted to the left and right axles 60 and 61 via the counter gears 51 and 52 and the differential device 9.

The torque of the engine output shaft 10 is transmitted to the input shaft 12 via the torque converter 6. In particular, at the time of starting, the torque is changed by the torque converter 6 so as to increase the torque ratio, and the torque is transmitted to the input shaft 12. It is transmitted and starts smoothly. Further, the torque converter 6 has a lock-up clutch 5, and when the vehicle is running at a predetermined speed or higher, the lock-up clutch is engaged, and the engine output shaft 10 and the input shaft 12 are directly connected. State
The loss due to the oil flow of the torque converter has been reduced. Further, until the clutch is completely engaged, the slip control is performed based on the output pressure by the duty control of the solenoid valve S2 described later so that the rotation difference between the input side and the output side of the lock-up clutch becomes a predetermined value.

That is, as shown in detail in FIG. 6, when the manual shift valve 75 is in the D range by the position sensor, the accelerator opening and the input rotation speed from the input rotation speed sensor are read from the map, and the control unit locks. An up OFF signal or an ON signal is output to the solenoid valve S1. When the solenoid valve S1 outputs the lock-up OFF signal pressure (release) from the output port p, the lock-up relay valve 81 is at the right half position by the urging force of the spring 81f. In this state, the secondary pressure (Psec) from the output port 71a of the secondary regulator valve 71 is supplied to the torque converter 6 from the lockup OFF port 6a via the oil passage g and the ports 81a and 81b of the relay valve 81, and The lock-up ON port 6b is guided to the cooler 91 via the ports 81c and 81d of the relay valve 81, whereby the lock-up clutch 5 is held in the disconnected state.

On the other hand, when the solenoid valve S1 inputs the lock-up ON signal from the control unit and outputs a signal pressure (supply), the signal pressure is supplied to the control oil chamber 80t, and the lock-up relay valve 81 is turned to the left half. Switched to position.
In this state, the secondary pressure from the oil passage g is supplied to the torque converter 6 from the lock-up ON port 6b through the ports 81a and 81c of the relay valve 81, and from the lock-up OFF port 6a to the port of the relay valve 81. It is guided to the port 82a of the control valve 82 via 81b and 81e and discharged from the drain port EX, whereby the lock-up clutch 5 is held in the connected state.

When the lock-up clutch is slip-operated, the control unit receives the input-side and output-side rotation speeds of the lock-up clutch, that is, a signal from the engine speed sensor and a signal from the input speed sensor. A signal is output so that the difference becomes a predetermined value. The duty of the solenoid valve S2 is controlled based on the signal, a predetermined control oil pressure is output from the output port h, and the control oil pressure acts on the intermediate control oil chamber 82b of the lock-up control valve 82. The lock-up control valve 82 has an upper control oil chamber 82d acting on the upper end of the spool 82c and a lower control oil chamber 82f acting together with a spring 82e at the lower stage of the spool. The hydraulic pressure from the up-OFF port 6a acts via the oil passage j, and the hydraulic pressure from the lock-up ON port 6b acts on the lower control oil chamber 82f via the oil passage k, thereby controlling the lock-up clutch on the spool 82c. Are operating in a differential pressure state.

When the control oil pressure by the duty control acts on the control oil chamber 82b in the state where the differential pressure is applied, the control valve 82 causes the spool 82c to move downward according to the control oil pressure and output the output oil. Port 82a
Communicates with the secondary pressure input port 82g and the drain port EX at a predetermined ratio. As a result, the hydraulic pressure from the lock-up OFF-side port 6a becomes a predetermined pressure, the ON-side oil chamber and the OFF-side oil chamber of the torque converter 6 are balanced, and the lock-up clutch 5 enters a predetermined slip state.

Next, a reverse gear establishment prohibition (reverse inhibit) mechanism will be described with reference to FIG. The lock-up relay valve 81 includes the lock-up clutch control ports 81a, 81b, 81c, and 8 described above.
In addition to 1d and 81e, ports 81g and 81h for reverse inhibition and a drain port EX are provided. The port 81i is connected to the secondary regulator valve 7
The lubricating oil from the first lubrication port 71b (see FIG. 2) is supplied via the oil passage r, and is in the lock-up ON position (left half position), and the ports 81i and 81d
And the oil is supplied to the lubricating hydraulic cooler 91. When the lock-up OFF position (right half position) is attained, the oil from the torque converter is supplied to the cooler 91 via the oil passage 81d. Is a measure for preventing supply at the ON position.

When the vehicle is in the drive range D and the vehicle is traveling at a predetermined speed or higher, the lock-up clutch 5 is in the connected state, and the lock-up relay valve 81
Is held at the ON position (left half position) by the ON signal pressure (supply) of the solenoid valve S1. In this state,
Even if the driver mistakenly operates the shift lever to the reverse range R, the input port PM of the manual shift valve 75 communicates with the reverse port R, and the clutch pressure of the input port PM is supplied to the port R, The oil pressure is shut off at the port 81g of the lock-up relay valve 81 via the oil passage b2, and the reverse brake hydraulic servo B1 is connected to the drain port EX via the oil passage n and the port 81h. . Therefore, in the steady running state of the predetermined speed or higher for the lock-up clutch is ON, even if the shift lever to the reverse range for example, possible to reverse brake B ₁ is engaged, to achieve the reverse state No (reverse inhibit). Further, in the above-described reverse inhibit, the lock-up relay valve 81 maintains the state of being kept in the ON state (the left half position), as in the prior art having a dedicated reverse inhibit (reverse gear inhibition) valve. ,
There is no time lag associated with switching valves.

When the vehicle decelerates to a predetermined speed or less and stops, the solenoid valve S1 is turned off (released) and the lock-up relay valve 81 is turned off (right half position) in preparation for the next start. ). In this state, as described above, the secondary pressure is supplied from the port 81a to the OFF port 6a of the torque converter via the port 81b, and the ON pressure is supplied to the ON port 6b and the port 81b.
The lock-up clutch 5 flows to the cooler 91 via c and 81d, and is in a disconnected state. When the vehicle at the predetermined speed or less is substantially stopped, the ports 81g and 81h of the relay valve 81 communicate with each other and the manual shift valve 7
5 is operated to the reverse position R to connect the input port PM and the reverse port R, the clutch pressure (or control pressure) is applied to the hydraulic servo B1 via the oil passage b2, the ports 81g and 81h, and the oil passage n. is supplied, the reverse clutch B ₁ is reverse speed is achieved engaged.

Further, during the operation of the reverse inhibit, that is, when the vehicle is traveling forward at a predetermined speed or more, the driver incorrectly operates the reverse gear and the shift lever is left in the reverse range. Or acceleration) or the like, a release signal of the lock-up clutch 5 may be output from the control unit. In this case, the solenoid valve S1
Means that the lock-up relay valve is ON while the signal pressure is output from the output port p by the ON signal from the control unit.
Position (left half position), and the reverse inhibit state in which the port 81g is shut off is maintained as it is. In this state, the solenoid valve S2 is in the OFF state,
That is, the lock-up control valve 82 is in the right half position by the urging force of the spring 82e, and the port 82g is in the released (zero pressure) state where the duty ratio is 0 [%].
And 82a are in full communication. Therefore, the secondary pressure P
sec is communicated with the port 81e of the relay valve 81 via the ports 82g and 82a, and further locked up via the port 81b of the valve at the ON position.
It is supplied to port 6a. In this state, in the torque converter 6, the same secondary pressure Psec is supplied to the ON side from the port 6b and the OFF side from the port 6a, the difference between the two chambers is eliminated, and the lock-up clutch 5 is held in the released state.

In the drive range D, when the solenoid valve S1 is turned on, the relay valve 81 is turned on.
The position is switched to the N position and the secondary pressure Psec is
When the hydraulic pressure from the lock-up OFF port 6a is supplied to the lock-up ON port 6b via the ports 81a and 81c, the hydraulic pressure from the lock-up OFF port 6a communicates with the control valve 82a via the ports 81a and 81c. Increases the duty ratio smoothly from the OFF state. Accordingly, the control valve 82 is in the right half position and the port 82a is supplied with the secondary pressure of the port 82g, that is, the lock-up OF
The same hydraulic pressure as the discharge pressure from the F port 6a is supplied, and as described above, the lockup clutch 5 is disengaged from the state where the two chambers of the torque converter are in the same state, and the duty ratio of the solenoid valve S2 is changed. Is supplied to the control oil chamber 82b by moving the spool 82c downward, and the port 82a
Is the secondary pressure supply port 82g and the drain port E
The communication ratio with X gradually increases toward the drain port side.
Thus, the lock-up clutch 5 is smoothly connected, and the control valve 82 is set to the left half position to completely connect the lock-up clutch through the drain port EX through the port 82a.

That is, the lock-up control valve 8
2 is the slip control of the lock-up clutch described above,
It has the functions of smooth engagement without shift shock when the clutch is connected, and release of the lock-up clutch at the time of reverse inhibition due to the addition of the reverse inhibit function to the lock-up relay valve 81.

Next, a mechanism for switching the hydraulic pressure to the hydraulic servo for the starting frictional engagement element according to the main part of the present invention will be described with reference to FIG. Ratio control valve 80
Are located at both ends of the spool 80a, respectively.
The control oil chambers are provided with springs 80b and 80c, respectively, and these springs and washers 80d and 80e are provided at both ends of the spool.
Is interposed. These washers have a cylindrical portion and a bottom wall portion. The cylindrical portion is slidably guided by the side walls of the control oil chambers 80s and 80t, and the bottom wall portion is the end of the spool and the control oil. It can abut the end of the chamber.

Further, the ratio control valve 80
Is provided with a spool 80a having a communicating portion formed of an annular concave portion at a central portion, and the downshift solenoid valve S3.
And a port 80f communicating with the output port e of the control oil chamber through an oil passage e2 and an orifice 95 and opening to one of the control oil chambers 80s.
4 is connected to the output port f via the oil passage f2 and the orifice 95, and the port 80h opened to the other 80t of the control oil chamber and the input to which the line pressure PL from the line pressure oil passage l is supplied. Supply) port 80g and the primary side hydraulic servo 33 (specifically, the hydraulic chambers 41 and 42).
, And two drain ports EX. The detailed configuration is described in Japanese Patent Application No. 11-210485 and Japanese Patent Application No. 11-37578.
No. 9 is described.

Then, the two solenoid valves S3, S
4 is OFF and the output ports e and f are open (0
Pressure), the control pressure does not act on both control oil chambers 80s and 80t, and the urging forces of both springs 80b and 80e act on both ends of spool 80a via washers 80d and 80e. The spool is positioned and held at the neutral position shown in the figure by the bottom wall of these washers abutting against the end face of the control oil chamber. In this state, both the supply port 80g and the output port 80i are in the cutoff state, and the primary-side hydraulic actuator 33
The CVT 2 is maintained at a predetermined speed ratio while maintaining a predetermined state without hydraulic pressure.

On the other hand, the downshift solenoid valve S
3 and the upshift-side solenoid valve S4, the solenoid modulator pressure from the solenoid modulator valve 83 is input to the input ports o and p, and the duty is controlled by a predetermined electric signal from the control unit, and the predetermined pressure is applied to the ports e and f. Outputs signal pressure.

In the drive range D, when the control unit makes a downshift determination based on a signal from the sensor, the duty of the solenoid valve S3 is controlled in accordance with the determination, and a predetermined signal pressure is output from its output port e. When a predetermined signal pressure from the output port e acts on the port 80f of the ratio control valve 80 via the oil passage e2 and the orifice 95 from the state where the ratio control valve 80 is held at the neutral position, the upper control oil Room 8
In response to the signal pressure acting on 0s, the spool 80a moves downward against the spring 80c.

Thus, the output port 80i communicates with the drain port EX at a rate corresponding to the predetermined signal pressure,
The hydraulic pressure of the primary hydraulic actuator 33 is drained at a predetermined speed, and
5, the CVT 2 shifts (downshifts) to a direction in which the effective diameter of the primary pulley 26 decreases, that is, to the underdrive side.

In the drive range D, when the control unit determines an upshift, the duty of the solenoid valve S4 is controlled in accordance with the determination, and a predetermined signal pressure is output from its output port f. Road f2,
Ratio control valve 80 through orifice 95
Port 80h.

The ratio control valve 80 moves the spool 80a upward against the spring 80b based on the signal pressure of the lower control oil chamber 80t, and
0g and the output port 80i are communicated at a predetermined ratio. Accordingly, the line pressure PL supplied from the oil passage l to the supply port 80g is adjusted to a hydraulic pressure corresponding to the predetermined signal pressure based on the duty control, and is supplied from the output port 80i to the primary hydraulic actuator 33. On the other hand, as described above, the secondary sheave control valve 73 is acted on by the secondary sheave control valve 73 with the predetermined secondary sheave pressure PSS in accordance with the input torque, thereby maintaining the belt holding force. When the hydraulic pressure is supplied to the primary-side hydraulic actuator 33 composed of a double piston, the CVT 2 shifts (upshifts) to a direction in which the effective diameter of the primary pulley 26 increases, that is, to the overdrive side.

When the shift lever is operated to switch the manual shift valve 75 from the neutral position N to the drive position D or the reverse position R, a downshift solenoid valve S3 is operated by a signal from a control unit based on the position sensor. And the upshift solenoid valve S4 is in the ON state, that is, the duty ratio 100
[%] Is switched to the full supply state. As a result, in the ratio control valve 80, the same modulator pressure is supplied to both control oil chambers from both the input ports 80f and 80h, and the urging forces acting on both ends of the spool 80a become the same. As in the case where the two solenoid valves S3 and S4 are in the OFF state, the solenoid valves are held at the neutral position. Therefore, the CVT 2 is maintained at the predetermined speed ratio, but is generally downshifted in the drive range D before the neutral position, which is the stopped state, and is in the lowest underdrive state. Note that, in the reverse range R, the ratio control valve 80 is not operated, and the CVT 2 is held at a predetermined position (generally, the lowest underdrive position).

The garage shift valve 79 is connected to the spool 7
A control oil chamber 79f is formed at one end (upper end) of 9g, a spring 79c is contracted at the other end (lower end), and a control oil chamber 79e is formed in the middle stage to urge downward based on the area difference. Have been. Also, the shift valve 79
Is an input (supply) port 79a to which clutch modulator pressures (operating pressure, range pressure) PB1 and PC1 are supplied from the clutch modulator valve 76, and an output port 79 communicating with the input port PM of the manual shift valve 75.
b, It has a control pressure input port 79d communicating with an output port 77c of the garage shift control valve 77. Further, the solenoid valves S3 and S3 are provided in the control oil chamber 79h in which the spring 79c is contracted.
The solenoid modulator pressure PSM from the solenoid modulator valve 83 supplied to the input ports p, o of No. 4
Is communicated.

The garage shift control valve 77 has a control oil chamber 77 at one end (upper end) of the spool 77s.
d, and a control oil chamber 77a to which the signal pressure PSLT from the linear solenoid valve SLT is supplied is formed at the other end. Further, the control valve 77 is connected to the clutch modulator pressure (operating pressure) PB
1, an input (supply) port 77b to which PC1 is supplied, a port 77c communicating with a control pressure (control pressure) input port 79d of the shift valve, and a drain port EX. The control pressure from the port 77c is: Acts as feedback pressure on the upper control oil chamber 77d,
The hydraulic pressure from the port 77c is connected to the input port PM of the manual shift valve 75 via the oil passage s and the check valve 96.

This state, that is, the manual shift valve 7
5, when the vehicle is switched from the neutral position N to the drive position D or the reverse position R, that is, when the vehicle starts moving forward or backward, the signal pressure in the full supply state from the two solenoid valves S3 and S4 becomes the oil passage e1 It is supplied to the control oil chambers 79e and 79f of the garage shift valve 79 through f1. As a result, the shift valve 79
The control oil chamber 79 acting downward due to the oil pressure of the control oil chamber 79f acting on the upper end of 9g and the area difference of the middle stage of the spool.
e, the spool 79g is moved to the lower end control oil chamber 79h.
Modulator pressure (original pressure) and spring 7
9c and is switched to the left position (control position).

In this state, the clutch pressure (direct pressure) PB1, PC1 from the input port 79a is supplied to the output port 79b, and the position is switched to a position where the control pressure input port 79d and the output port 79b communicate with each other. , The control pressure PCC from the garage shift control valve 77 is output from the output port 79b. As described above, the control valve 77 is
As shown in FIG. 4, the clutch pressure is reduced to the control pressure PCC by the signal pressure PSLT from the linear solenoid valve SLT, and is output from the output port 77c. Manual shift valve 75 via oil passage m
Is supplied to the input port PM.

When switching from the neutral range N to the drive range D (N → D), the input port P
The control pressure from M is the manual shift valve 7
From port D of No. 5 via oil passage d and orifice 95,
It is supplied to the direct clutch hydraulic servo C1. At this time, the control pressure is controlled by the control valve 77.
Is controlled by the signal oil pressure from the linear solenoid valve SLT supplied to the control oil chamber 77a, and rises smoothly. Thus, direct (input) clutch _{C 1} is
The forward and backward switching device 3 is connected smoothly to the input shaft 12 and the primary pulley 26 so as not to cause a shift shock.
Is directly connected to the vehicle. When shifting the shift lever to the low range L, the input port PM of the manual shift valve 75 also communicates with the right end port D,
As described above, the control pressure PCC is supplied to the clutch hydraulic servo C1.

On the other hand, when switching from the neutral range N to the reverse range R (N → R), the input port PM
Control pressure from the manual shift valve 75
Is supplied to the reverse brake hydraulic servo B1 via the oil passage b2, the ports 81g and 81h of the lock-up relay valve 81, the oil passage n and the orifice 95, and the control pressure is supplied to the linear solenoid as described above. It rises smoothly by the signal oil pressure of the bubble SLT.
Accordingly, the reverse brake B ₁ represents connects smoothly so as not to cause a shift shock, the forward-reverse switching apparatus 3
The ring gear R is fixed, and the rotation of the input shaft 12 is transmitted to the primary pulley 26 through the double pinion planetary gear 50 as reverse rotation / reduced rotation.

When the engagement of the direct clutch C ₁ or the reverse brake B ₁ is completed due to the lapse of a predetermined time from the detection of the position sensor or the achievement of the predetermined engagement state by the rotation sensor, a signal from the control unit is issued. The full supply state of the two solenoid valves S3 and S4 is released. In this state, that is, when at least one of the two solenoid valves is turned off (released), the garage shift valve 79 is switched to the right half position (direct position) by the solenoid source pressure of the control oil chamber 79h and the urging force of the spring 79c. In this state, as described above, the clutch pressure from the clutch modulator valve 76 is applied to the manual shift valve 75 via the output port 76b, the oil passage c1, the strainer 85, the oil passage c2, the ports 79a, 79b, and the oil passage m. It is supplied to the input port PM. And
Based on the range D or R of said shift valve, said clutch pressure (direct pressure) is supplied to the hydraulic servo C1 or B1, to ensure engagement state in response to the input torque to direct clutch C ₁ or the reverse brake B ₁ Hold.

[0073] Incidentally, the two hydraulic servo C1, the oil passage communicating with the B1 d, check valve 96 interposed m, the direct clutch _{C 1,} when releasing the reverse brake _{B 1,} so that there is no delay, the orifice 95 This is for draining the hydraulic pressure of the hydraulic servo quickly without going through.

Ratio control valve switching described above
Of the two solenoid valves S3 and S4 for
FIG. 8 (a) shows the switching relationship of the image shift valve 79.
A description will be given collectively along a simplified embodiment shown in FIG.
You. Garage shift valve 79 ₁Is shown in FIG.
One spool 79g and the top of the spool
Area difference between the control oil chamber 79f to be used and the land (for example,
Control oil chamber 79e acting on the same area difference as the upper end of the
A spring 79c acting on the lower end of the spool,
Pressure (clutch modulator pressure, range pressure, working pressure)
PB1, PC1 input port 79a and control pressure
(Control pressure) input port 79d and output port 79b
Having. The spring 79c is connected to the control oil chamber 79.
Left half position even if hydraulic pressure acts on either f or 79e
(Direct position) and hydraulic pressure is applied to both control oil chambers.
Spool in right half position (control position)
The elastic modulus and initial pressure are set so that
You.

Then, as shown in FIG. 8B, a normally closed type downshift solenoid valve S
When 3 is ON to supply (duty control) and the upshift solenoid valve S4 is OFF to discharge (release, 0 pressure), the ratio control valve 80 is at the discharge position of the primary hydraulic actuator and is in a downshift state. When the solenoid valve S3 is turned off to discharge and the solenoid valve S4 is turned on to supply (duty control), the ratio control valve 80 is in the supply position to the actuator and is in an upshift state, and both solenoid valves S3 and S4 are in the upshift state. If both are OFF and ejected,
The ratio control valve is in the shut-off position held at the neutral position, and the CVT is held at a predetermined gear ratio.

[0076] Then, the garage shift valve 79 _1,
In the three states of the solenoid valves S3 and S4, that is, when at least one of the two solenoid valves is OFF and in the discharge state, the control pressure does not act on at least one of the two control oil chambers 79f and 79e, and the spool 79g Is at the left half position (direct position) by the spring 79c. In this state, the clutch pressure (direct pressure, operating pressure, range pressure) is supplied to the input port PM of the manual shift valve 75 via the ports 79a, 79b.

Both solenoid valves S3 and S4 are ON
In the supply state, the same solenoid modulator pressure is supplied to the upper and lower control oil chambers of the ratio control valve 80, and the shut-off is maintained at the neutral position as in the case where both the solenoid valves are both at the OFF position. And the CVT is maintained at the predetermined gear ratio. In this state, the garage shift valve 79 _1, two control oil chamber 79
The control pressure acts on both f and 79e, and the spool 79g
Is switched to the right half position (control position) against the spring 79c, and the control (control) pressure from the control valve 77 is output via the ports 79d and 79b and guided to the input port PM of the manual shift valve.

The spool shown in FIG.
The two control oil chambers 79f, 7f urge 9g downward.
9b is arranged, and a spring 79c is contracted so as to urge the spool 79g upward.
Accordingly, the position of the spool 79g is determined in a balanced manner by the urging force of the two control oil chambers from above and the spring elastic force from below, so that the two control oil chambers 79f, 79
(e) The spool is not reliably held at the direct position due to changes in the working oil pressure, for example, the control oil pressure based on the input torque, etc., and the switching between the direct position and the control position can be accurately and reliably performed depending on the running condition of the vehicle. There is no fear.

The embodiment shown in FIGS. 2 and 7 is improved in that point, and will be described with reference to FIGS. 9 (a) and 9 (b). Garage shift valve 79 has a spool 79g
A spring 79c is contracted at the lower end of the cylinder and a control oil chamber 79h is formed via a plunger 79i.
As shown in FIG. 7, the supply pressure of the solenoid valves S3 and S4, that is, the solenoid modulator pressure (original pressure) PSM from the solenoid modulator valve 83 is supplied to the control oil chamber 79h through an oil passage v. The three control oil chambers 79f, 79e, and 79h are set so that the areas where hydraulic pressure acts are the same.

One of the two solenoid valves S3 and S4 is in a full supply state with a duty ratio of 100 [%], and the same oil pressure as the solenoid modulator pressure (original pressure) is supplied to one of the control oil chambers 79f or 79e. In this state, the same solenoid source pressure is supplied to the lower end control oil chamber 79h. Therefore, as shown in FIG. 9B, even if the solenoid source pressure PSM changes, these solenoid source pressures PS are kept in the same area in the opposite direction to the spool.
Since M acts together to cancel (cancel) each other, the garage shift valve 79 keeps the switching start hydraulic pressure and the switching completed hydraulic pressure constant at all times, regardless of the solenoid's original pressure and therefore the running condition of the vehicle. And the hydraulic pressure required to switch the garage shift valve 79 is
Regardless of the position of any signal pressure, the value is always constant based on the urging force of the spring 79c.

Thus, by setting the solenoid source pressure to a hydraulic pressure larger than the switching hydraulic pressure, the solenoid source pressure is supplied to the other control oil chamber 79f or 79e by turning on the other solenoid valve S4 or S3. Thus, the garage shift valve 79 can be quickly and reliably switched in any running condition.

[0082] FIG. 10 (a) (b) are those showing an embodiment partially modified structure of the garage shift valve 79 ₂ is that of the previous embodiment FIG. 7, FIG. 9 (a)] and Approximately the same, but the lower control oil chamber 7 acting on the plunger 79i
The difference is that the hydraulic working area of 9h is larger than the working area of the control oil chamber 79f acting on the spool from above by a predetermined amount.

Accordingly, when one of the solenoid valves S3 and S4 is in a supply state with a duty ratio of 100%, the solenoid modulator pressure (original pressure) PSM is supplied to one of the control oil chambers 79e and 79f. In this state, the solenoid modulator pressure (source pressure) PSM also acts on the lower end control oil chamber 79h. The operating pressure of both control oil chambers is the solenoid modulator pressure PSM which is the original pressure.
The spool 79g is always urged to be in the right half position (direct position) based on the area difference between the two control hydraulic pressures regardless of the change of the control hydraulic pressure. Then, when the solenoid pressure is supplied to the other control oil chamber by turning on the other solenoid valve S4 or S3, the urging force downward of the spool due to the solenoid pressure is larger than the urging force upward of the spool due to the area difference. Therefore, the spool is immediately switched to the left half position (control position).

When the solenoid valves S3 and S4 are in a full supply state with a duty ratio of 100 [%], FIG.
As shown in FIG. 0 (b), the switching start oil pressure due to the area difference is proportional to the solenoid modulator pressure PSM which is the original pressure. Therefore, the garage shift valve 79 ₂
When the solenoid pressure PS is supplied to one of the control oil chambers (of course, when both control oil pressures are released), the control oil chamber is always at the direct position regardless of the signal pressure, and the original pressure and the signal pressure Is definitely in the direct position even if fluctuates. Therefore, when the solenoid pressure is supplied to both control oil chambers, the control position is quickly and reliably switched to the control position in any situation.

Next, another embodiment will be described with reference to FIGS. 11 (a) and 11 (b). Garage shift valve 79 ₃ of the present embodiment is similar substantially as that shown in FIG. 8 (a), and the position of the clutch pressure input port 79a and the control pressure input port 79d is reversed, and a spring 79c Is held at the left half position (direct position) when one of the two solenoid valves S3, S4 is supplied,
The spring constant and the initial pressure are set so that the solenoid valve is switched to the right half position (control position) only when both solenoid valves are supplied.

Then, the solenoid valves S3 and S4 are
It consists of a normally open type duty solenoid valve and operates as shown in FIG. That is,
When the solenoid valve S3 is turned off and supplied, and S4 is turned on and discharged, the ratio control valve 80 is downshifted by discharging the output port. When S3 is turned on and discharged, and when S4 is turned off and supplied, the control valve 80 outputs. The control valve 80 is supplied to the port to perform an upshift. When both solenoid valves S3 and S4 are turned off, the output port of the control valve 80 is shut off and the control valve 80 is held at a predetermined gear ratio.

[0087] When at least one of the solenoid valves S3, S4 are in the supply state off, the garage shift valve 79 _3, the upper biasing force under direction of the spool by one of the control oil chamber 79e or 79f said that by the spring 79c It is in the right half position (direct position) greater than the urging force. In this state, the clutch pressures (direct pressure, operating pressure, range pressure) PB1 and PC1
a, 79b. When both solenoid valves S3 and S4 are on and both are in the discharge state, the ratio control valve 80 is at a position where the output port is shut off, holds the CVT at a predetermined gear ratio in the same manner as the above-mentioned both off, and garage shift valve 79 _3, both the control oil chamber 79f, 79 e are discharged together, the spool 79g is switched to the left half position (control position) by the biasing force of the spring 79c. In this state, the control pressure (control pressure) from the control valve 77 is applied to the port 7
9d and 79b.

In the embodiment shown in FIG. 12, a plug 79j is provided at one end of a spool 79g, a control oil chamber 79f is provided at the upper end of the plug, and the plug 79j acts on both the plug and the spool. A control oil chamber 79e is disposed in the control oil chamber, and the control oil chamber applies hydraulic pressure to the lower end of the plug 79j and the upper end of the spool 79g in the same area. This garage shift valve 79 _4, the biasing force of the spring 79c so that the value lower than the solenoid pressure PS which acts on one of the control oil chamber 79f is set.

Therefore, when the control pressure is supplied from the solenoid valve S3 to the control oil chamber 79e, the plug 79j
The upper end abuts and moves the spool 79g downward against the spring 79c to hold it at the right half position (direct position) and supply clutch pressure via the ports 79a and 79b. Further, the control oil chamber 7 is controlled by the solenoid valve S4.
Similarly, when the control pressure is supplied to 9f, the spool 79g is set to the lower position via the plug 79j, and when the control pressure is supplied to both control oil chambers 79e, 79f from both solenoid valves S3, S4. , Right half position (direct position). Only when both of the control oil pressures 79e and 79f are discharged, the spool is moved to the left half position (control position) by the spring and the control pressure PCC is supplied through the ports 79d and 79b.

The garage shift valve 79 ₅ shown in FIG.
The plug 79j is disposed between the lower end of the spool 79g and the spring 79c, and one control oil chamber 79f is formed in a portion between the plug and the spool, and the other control oil chamber is formed at the lower end of the plug. An oil chamber 79e is formed. Further, a control oil chamber 79h to which a solenoid modulator pressure (signal pressure) PSM serving as an original pressure is supplied is formed at an upper end of the spool. In addition, each control oil chamber 79f,
The pressure receiving areas of 79e and 79h are all set to be the same, and the plug 79j is a foot 7 that regulates the downward movement amount.
9m.

Therefore, when the control pressure (duty ratio 0 [%]) is supplied from at least one of the solenoid valves S3 and S4 to the control oil chambers 79e and 79f,
The clutch 79 is at the right half position (direct position) by the urging force of the spring 79c, and the clutch pressure is supplied through the ports 79a and 79b. Also, both solenoid valves S3, S4
When both are ON and both control oil chambers 79e and 79f are in the released state, the spool is moved to the left half position (control position) against the spring 79c by the solenoid original pressure acting on the control oil chamber 79h. In this state, control pressure is supplied via ports 79d and 79b.

[0092] garage shift valve 79 shown in FIG. 14 ₆
The control oil chamber 79h in which the solenoid source pressure PSM acts is formed at the upper end of the spool 79g, and the spring 79c is contracted at the lower end.
k is formed. Also, one solenoid valve S
3 and an input port 90a, 90b communicating with the other solenoid valve S4, an output port 90c communicating with the control oil chamber 79k, and a ball 90d for switching the input port to the supply pressure side. A valve 90 is provided. The pressure receiving areas of the two control oil chambers 79h and 79k are set to be equal.

Therefore, when the control pressure is supplied from at least one of the solenoid valves S3 and S4 (or from both) to the control oil chamber 79k via the double check valve 90, the spool 79g is moved to the upper end thereof. The solenoid source pressure PSM acting on the control oil chamber 79h and the control pressure (pressure equal to the original pressure) acting on the control oil chamber 79k at the lower end thereof are balanced and are at the right half position (direct position) by the spring 79c. In this state, clutch pressure is supplied via ports 79a and 79b. When both solenoid valves S3 and S4 are turned on and the control oil chamber 79k at the lower end is released, the spool is in the left half position against the spring based on the solenoid original pressure PSM acting on the control oil chamber 79h at the upper end ( Control position). In this state, control pressure is supplied via ports 79d and 79b.

[0094] Although it is not preferable in terms of fail-safe,
A normally open type solenoid valve may be applied to the garage shift valve shown in FIGS. 8, 9, and 10. In this case, the operation table of the solenoid valve shown in FIG. X) is reversed, and a normally closed solenoid valve may be applied to the garage shift valve shown in FIGS. 11, 12, 13, and 14. In this case, the operation of the solenoid valve shown in FIG. In the table, ON (○) and OFF (×) are reversed.

Further, the above-described embodiment has been described using the belt-type continuously variable transmission. However, the present invention is not limited to this, and it is possible to use a ratio control valve (transmission control valve) for another CVT such as a toroidal type. It is needless to say that the same can be applied to the above. Further, the present invention is similarly applied to not only a continuously variable transmission (CVT) but also a control valve that switches between three operating states of supply, discharge, and holding by a combination of two solenoid valves. I can do it.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a continuously variable automatic transmission to which the present invention is applied.

FIG. 2 is a diagram showing the hydraulic circuit.

FIG. 3 is a diagram showing an operation table thereof.

FIG. 4 is a diagram showing each hydraulic pressure by a control hydraulic pressure of a linear solenoid valve.

FIG. 5 is a diagram showing clutch pressure by control hydraulic pressure of a linear solenoid valve.

FIG. 6 is an enlarged view showing a hydraulic circuit related to a reverse inhibit portion.

FIG. 7 is an enlarged view showing a main part of the hydraulic circuit according to the present invention.

8A and 8B are diagrams showing a simplified embodiment of the present invention, in which FIG. 8A is a sectional view showing a simplified switching valve (garage shift valve), and FIG. 8B is an operation table.

9A is a sectional view showing a switching valve (garage shift valve) of the hydraulic circuit, and FIG. 9B is a view showing the relationship between the signal pressure and the switching oil pressure.

10A is a cross-sectional view showing a partially changed switching valve, and FIG. 10B is a diagram showing the relationship between the signal pressure and the switching oil pressure.

FIG. 11 (a) is a sectional view showing a switching valve according to another embodiment, and FIG. 11 (b) shows an operation table thereof.

FIG. 12 is a sectional view showing a switching valve according to another embodiment.

FIG. 13 is a sectional view showing a switching valve according to another embodiment.

FIG. 14 is a sectional view showing another embodiment.

[Explanation of symbols]

2 stepless transmission 75 manual shift valve 79 ₁ to 79 ₆ switching valve (garage shift valve) 79a (operating pressure) input port 79b output port 79c spring 79d (control pressure) input port 79e control oil chamber 79f control oil chamber 79g spool 79h control oil chamber 79j plug 79k control oil chamber 80 (shift) control valves (ratio control valve) 80i output port B1, C1 hydraulic servo B _{1, C 1} frictional engagement element (the reverse brake, the direct clutch) S3, S4 Solenoid valve e, f Output port o, p Input port 90 Selection valve (double check valve) 90a, 90b Input port 90c Output port 90d Switching mechanism (ball)

 ──────────────────────────────────────────────────続 き Continued from the front page F term (reference) 3J552 MA07 MA12 MA26 NA01 NB01 PA66 QA10C QA24C QA26C QB05 RA02 RA03 RA06 RB01 RB03 SA35 SB13 SB15 SB19 SB20 TB01 TB03 TB07 VA07W VA17W VA58W VA64W VA65W VA66W VA74W VA79W

Claims (12)

[Claims] A control valve for switching an output port between a supply position, a discharge position, and a shut-off position by a combination of two solenoid valves and a signal pressure from the two solenoid valves; A hydraulic servo for the frictional engagement element, and a switching valve for switching the hydraulic pressure supplied to the hydraulic servo between an operating pressure for fastening the frictional engagement element and a control pressure for smooth connection. A hydraulic control device for an automatic transmission, wherein the switching valve is switched by a combination of three solenoid valves other than the three types of switching of the control valve. 2. The control valve according to claim 1, wherein the control valve controls the continuously variable transmission to shift up at the supply position, shift down at the discharge position, and hold at the shutoff position. 2. The hydraulic control device for an automatic transmission according to claim 1. 3. The hydraulic control device for an automatic transmission according to claim 1, wherein the switching valve is switched between a case where the two solenoid valves output a signal pressure together and a combination other than the two. 4. The control valve assumes the discharge position when one of the two solenoid valves outputs a signal pressure and the other discharges, the other outputting a signal pressure and one discharging. When the supply position is taken, the shutoff position is taken when both of the solenoid valves are discharged together, and the switching valve outputs the operating pressure when the combination of the two solenoid valves is in the three types. The hydraulic control device for an automatic transmission according to claim 3, wherein the hydraulic pressure control device takes a position where the control pressure is output when the two solenoid valves output a signal pressure together. 5. The hydraulic control device for an automatic transmission according to claim 1, wherein the switching valve is switched between a case where the two solenoid valves discharge together and a combination other than the case where the two solenoid valves discharge. 6. The control valve assumes the discharge position when one of the two solenoid valves outputs a signal pressure and the other discharges, the other output a signal pressure and one discharges. At the time of the supply position, and when the two solenoids output the signal pressure together, they take the shut-off position. The switching valve controls the operating pressure when the three solenoid valves are combined with each other. The hydraulic control device for an automatic transmission according to claim 5, wherein the control pressure is output when the two solenoid valves are discharged together, and the control pressure is output when the two solenoid valves discharge together. 7. The control valve, wherein the switching valve is arranged to bias the spool in one direction and communicates with the output ports of the two solenoid valves, respectively, and biases the spool in the other direction. The hydraulic control device for an automatic transmission according to any one of claims 3 to 6, further comprising a spring arranged as described above. 8. The control valve, wherein the switching valve is arranged to urge the spool in one direction and communicates with output ports of the two solenoid valves, respectively, and urges the spool in the other direction. The hydraulic control device for an automatic transmission according to any one of claims 3 to 6, further comprising: a control oil chamber that is arranged to communicate with an input port of the solenoid valve. 9. The switching valve includes a spool, a plug that can be brought into and out of contact with the spool, a control oil chamber that urges one end of the plug and communicates with one output port of the two solenoid valves. 7. The automatic transmission hydraulic control device according to claim 5, further comprising: a control oil chamber that operates between the other end of the plug and the spool and communicates with the other output port of the two solenoid valves. 8. . 10. An input port and an output port respectively communicating with output ports of the two solenoid valves,
A switching mechanism for switching one of the input ports so as to output a supply pressure to an output port, the switching valve being arranged to urge a spool in one direction, wherein the solenoid is disposed. The control oil chamber communicating with an input port of the valve, and a control oil chamber communicating with an output port of the selection valve, which is arranged to bias the spool in the other direction, is provided. Automatic transmission hydraulic control device. 11. The hydraulic servo for a frictional engagement element that engages at the time of starting includes a hydraulic servo for a frictional engagement element that engages at the time of forward travel, and a hydraulic servo for a frictional engagement element that engages at the time of reverse travel. Item 11. The hydraulic control device for an automatic transmission according to any one of Items 1 to 10. 12. A manual shift valve which is operated by a driver, and which is arranged so as to supply an operating pressure or a control pressure output from the switching valve to an input port of the manual shift valve. A hydraulic control device for an automatic transmission according to claim 1.