JPS60211150A - Hydraulic control unit for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent a simultaneous engagement between an L range friction engaging device and a second gear friction engaging device from occurring, by connecting a 2-range input port of a second gear holding valve to a drain, in case of the L range. CONSTITUTION:A 2-range input port 232 of a second gear holding valve 216 is connected to a second output port 228 of an L range shift valve 200. With this constitution, even if the second gear holding valve 216 is tightly attached to a Z range position, at the L range, a Z range input port 232 of the second gear holding valve 216 is connected to a drain, and second engaging pressure is in no case led thereinto, so that a second gear friction engaging device comes into a state of being set free, thus a simultaneous engagement between an L range friction engaging device and the second gear friction engaging device is prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a hydraulic control device for an automatic transmission that fixes the transmission to the second speed in the second range.

Conventional technology 2 (In a hydraulic control device for an automatic transmission that performs control to fix the 2nd gear in the 2nd range, the control is applied to the 2nd gear friction engagement device in the 2nd range regardless of the position of the l-2 shift valve. It is necessary to guide the engagement pressure. Therefore, in the 2nd range, a 2nd speed holding valve is provided that guides the line pressure as the engagement pressure to the 2nd speed friction engagement device regardless of the operation of the 1-2 shift valve. However, if this 2nd speed holding valve is stuck in the position that leads the line pressure to the 2nd speed friction engagement device, when the L (low) range is reached, the range friction engagement device and the 2nd speed friction engagement device will be disconnected. At the same time, the frictional engagement device becomes engaged and damage occurs.

Purpose An object of the present invention is to provide a hydraulic control system for a self-excited transmission that fixes the second speed in the second range, and to solve the problem of the friction engagement device for the second speed and the friction engagement device for the L range due to the sticking of the valve. In order to achieve this objective, the hydraulic control device for an automatic transmission of the present invention is configured to prevent simultaneous engagement states. A frictional engagement device for the L range, a frictional engagement device for the second speed that enters the engaged state by being supplied with the second engagement pressure in the second speed, and a second locking device for the second linked frictional engagement device. The second speed holding valve has an output boat for guiding pressure and is held in a position connecting the input boat for the two ranges to the output boat for the two ranges, and a first speed holding valve that is connected to the friction engagement device for the L range. It has an output boat and a second output boat connected to the input boat for the second range of the second speed holding valve, and in the second range, the second holding pressure is guided to the second output boat in the L range. A shift valve for guiding the first holding pressure to the first output boat and connecting the second output boat to the drain is provided.

In the action 2 range, the L range shift valve and the 2nd speed holding valve are in the 2 range position, so the second engagement pressure is
It is guided to the 2nd speed friction engagement device via the second output boat of the L range shift valve, the 2nd range input boat and output boat of the 2nd speed holding valve, and as a result, the 2nd speed friction engagement device The combined device enters the secured state.

In the L range, the L range shift valve is in the L ring 9 position, so the first holding pressure is led to the L range friction engagement device via the first output port of the L range shift valve, and this As a result, the frictional engagement device for the L range enters the locked state. At the same time, the second output port of the L range shift valve is connected to the drain, so the 2nd range input port of the second speed holding valve is connected to the drain via this 24th output port. .

Effect In this way, even if the 2nd speed holding valve is stuck in the 2nd range position, in the L range, the 2nd range input port of the 2nd speed holding valve is connected to the drain, and the 2nd engagement pressure is not introduced. Therefore, the second continuous frictional engagement device is in a released state, and simultaneous engagement of the L-range frictional engagement device and the second continuous frictional engagement device is prevented.

Preferably, the second joint pressure is line pressure, and the first joint pressure is an oil pressure lower than the line pressure by a predetermined value.

Preferably, the second speed holding valve has an input port for the drive range, and the second speed holding valve has a 1-
Line pressure is guided from the 2-shift valve to the drive range input boat, and in the drive range it is held in a position where the drive range input boat is connected to the output boat.

Example The invention will be explained in detail with reference to the embodiments shown in the drawings.

FIG. 1 shows the division of the entire hydraulic control circuit diagram.

In FIG. 2, an oil pump 0 is driven by an engine to pressurize and discharge oil sucked in through a strainer 12. The line pressure oil passage 14 is connected to the discharge side of the oil pump IO, and the relief valve 16 defines the upper limit of the line pressure Pl of the line pressure oil passage 14. The primary regulator valve 18 controls the boat 20 connected to the line pressure oil passage 14, the boat 24 connected to the suction side of the oil pump IO via the oil passage 22, and the connection between the boats 20 and 24. I am using spool 26. boat 2
8 is supplied with a first throttle pressure Pthl that is a first increasing function of the throttle opening of the intake passage, and as the first throttle pressure Pthl increases, the oil flow rate flowing from the boat 20 to the boat 24 increases. decreases, line pressure P
l is an increasing function of the first throttle pressure Pthl. Boat 30 has line pressure P7 from the manual valve when in R range or 2 range! is supplied, thereby R,
The line pressure P/ in the boat 20 during the 2nd range is determined. The oil passage 32 connects to the line pressure oil passage 14 via an orifice 34.
is connected to the secondary regulator valve 36
has a boat 40 connected to the suction side of the oil pump 10 via an oil passage 38, a spring 42, and a boat 44 supplied with the first throttle pressure Pthl;
The oil pressure in the oil passage 32 is controlled by controlling the discharge flow rate of oil from the oil passage 2 to the boat 40 in relation to the splash 42 and the first throttle pressure Pthl. The oil passage 41 is connected to an oil cooler 43, and the relief valve 45 limits the upper limit of the oil pressure of the oil passage 41.

In FIG. 3, the manual valve 46 includes an input port 48 connected to the oil line 14, an output port 50 connected to the input boat 48 in the R range, an output port 52 connected to the input boat 48 in the L range, and an output port 52 connected to the input boat 48 in the L range. , output port 54 connected to input port 48 when in 2 range, L,
The output port 56 is connected to the input port 48 during the 2.3 range, and the 2, 3 . Input boat 4 when in D range
It has an output port 58 connected to 8. The two-range modulator valve 6o has an input port 4 connected to the boat 54 via an oil line 62, and an output port 8 connected to an oil line 66.
Then, a modulator pressure that is appropriately lower than the line pressure Pl is generated.

In FIG. 4, the D-2 timing valve 70 is connected to the boat 58 via an orifice 72, and is connected to a boat 74 and an oil line 6 to which line pressure Pl is supplied during the forward travel range.
6 and modulator valve 6 when in 2nd range.
Input port door 6 and oil line 7 to which modulator pressure of 0 is sent
output port 80 connected to 8, and clutch C
It has a boat 86 that is connected to the O hydraulic cylinder through an orifice 84, and controls the modulator pressure of the input port door 6 after the clutch CO is engaged when shifted from the D range to the 2nd or 2nd ranges. Output port 8
Lead to 0. The oil passage 78 is connected to a 2-3 shift valve, which will be described later, and the 2-3 shift valve is switched from a high-speed side to a low-speed side position by modulator pressure from the oil passage 78.
In addition, clutch Co is a clutch that is engaged to ensure engine braking in 1st to 3rd gears, so if there is a shift range from D range to 2nd range, clutch CO will be engaged. After this, the third gear is held until the vehicle speed decreases appropriately, thereby preventing a direct shift from the fourth gear to the second gear.

The L range modulator valve 88 has an input boat 92 connected to the boat 52 via an oil line 90 and an output port 96 connected to an oil line 94, and outputs a predetermined modulator pressure in the L range. Occurs on port 96. The control valve 98 connects the oil passage 100 from the 2-3 shift valve when the 2-3 shift valve is in the low speed side position.
Boat 102.3 to which line pressure Pl is sent via
When the -4 shift valve is in the low speed position, the boat 106 receives line pressure Pl from the 3-4 shift valve via the oil line 104, and is connected to the boat 54 of the manual valve 46 via the oil line 62. Boat being +08
, and an output boat 110 connected to the hydraulic cylinder of the clutch CO. 3-4 when in 3 range
The boat 106 line pressure p4 is sent from the shift valve, and the boat 108 line pressure Pl is sent from the manual valve 46 in the L and 2 ranges, so 3, 2. L
When in the range, line pressure P of boat 106 or 108
l is guided to the output boat 110, and the engine brake clutch CO is engaged.

In FIG. 5, the first throttle valve 112 includes an input port 114 connected to the line pressure oil passage 14, an output port 118 connected to the oil passage 116 and generating the first throttle pressure pthl, and a flow of the input boat 114. The throttle pressure Pt corresponds to the acting force of the splash 124 by controlling the road area.
A spool 120 that generates a
3, the spool 12 is operated by a throttle cam 122 to bias the spool 120 via a spring 124.
6. As the opening degree of the throttle valve in the intake passage increases, the flow cross-sectional area of the input port 114 increases, so the first throttle pressure pth1 becomes an increasing function of the throttle opening degree. The cutback valve 128 connects the boat 130 and the oil passage 132 to which the first throttle pressure pth1 is sent.
a boat 134 to which the governor pressure Pgo is sent via the boat 134 and a boat 136 that generates the control pressure for the first throttle valve 112, and appropriately limits the first throttle pressure pt with respect to the governor pressure Pgo; To prevent power loss of the oil pump 10. The second throttle valve 140 is
an input boat 142 connected to the line pressure oil passage 14;
An output boat 146 that is connected to the oil passage 144 and generates a second throttle pressure Pth2, a spool 148 that controls the flow passage cross-sectional area of the input port 142 to generate a throttle pressure Pth2 corresponding to the acting force of the spring 152, and an intake air It has a throttle cam 150 that interlocks with a throttle valve in the passage, and a downshift plug 154 that is operated by the throttle cam 150 via a roller 151 and urges the spool 148 via a spring 152.

As the opening degree of the throttle valve in the intake passage increases, the flow cross-sectional area of the input port 142 increases, so the second throttle pressure Pth2 becomes an increasing function of the throttle opening degree. The downshift plug 154 is connected to the boat 15 when the throttle valve in the intake passage is nearly fully open, that is, during kickdown.
6 to the boat 160. The detent regulator valve 162 has an input port 166 connected to the boat 160 via an oil passage 164, and generates a predetermined detent pressure to an output boat 170 connected to an oil passage 168. When the throttle opening reaches 85% or more, the downshift plug 1'54 connects the oil passage 144 to the boat 160, and the second throttle pressure Pth2 is introduced to the boat 160.

In FIG. 6, the governor valve 174 is connected to the oil line 1 connected to the boat 58 of the manual valve 46 (the line pressure Pl is introduced to the boat 58 during forward travel range).
It has an input port 180 to which line pressure Pl is sent from 76 through a strainer 178, and governor pressure P related to vehicle speed is sent to an output boat 182 connected to the oil line 132.
Generate go.

The 1-2 shift valve 184 is connected to a boat 186 to which the governor pressure Pgo is sent via the oil line 132, a boat 188 to which the second throttle pressure Pth2 is sent via the oil line 144, and an oil line 176. input boat 19
0, Output boat 194 connected to oil line 192, Output boat 194 connected to input boat 190 or drain 19
6 and has a spool 198 selectively connected to 6. The spool 198 disconnects the input port 190 from the output boat 194 and connects the output boat 194 to the drain 196 at the low speed position, that is, the first speed position, and connects the output boat 194 to the drain 196. Output boat 19 in position
4 is connected to the input boat 190. The shift valve 200 for the 1° range is connected to the oil passage 9 through the orifice 202.
4, an input port 208 connected to the boat 50 of the manual valve 46 (line pressure P7 is introduced in the R range) via an oil line 206, an input port 208 connected to the boat 50 of the manual valve 46 (line pressure P7 is introduced in the R range), and an input port 208 connected to the boat 50 of the manual valve 46 (line pressure P7 is introduced in the R range). The output port 210 is connected to the hydraulic cylinder of the brake B2 which is engaged at the time of input boat 2.
It has a spool 212 that connects to either of 08 and 210. As a result, in the L range and the R range, the hydraulic pressure from the input boats 204 and 208 is guided to the brake B2 via the output port 210, and the brake B
2 becomes a cohesive state. In the L range, the spool 212 moves toward the 1-2 shift valve 184 and holds the spool 190 of the 1-2 shift valve 184 at the low speed side position. The first speed of the forward range is activated by engagement of a one-way clutch in parallel with brake B2, and spool 212 receives a force from spring 214 toward input boat 204.

The second speed holding valve 216 includes an input port 21a connected to the oil passage 192, an output port 222 connected to the h passage 220, and a boat 224 connected to the oil passage 78.
, Bow 1-226, 2 of shift valve 184 for L range
In the 3.2.L range, the line pressure is P/, and the spool 212 connects the boat 226 to the boat 228 in the D, 3.2 range. and connects the boat 226 to the drain 229 in the L range.) The input port 232 is connected to the oil line 230 to which the line pressure Pl is guided, and the spool connects the output port 222 to the input boat 218 or 232. It has 234.

The spool 234 is in the D and 3 ranges (i.e. boat 2
When there is no oil pressure in 24. ) is pushed toward the boat 224 by a spring 236, and the l-2 shift valve 18
4 is in the high speed side position, the line pressure Pl of the input boat 218 is guided to the output port 222.

In addition, the spool 234 is connected to the boat 224 at the time of 2 ranges.
moves toward the input boat 236 due to the hydraulic pressure of the input boat 21
8 line pressure Pl is guided to the output port 222. Oil road 22
0 is connected to the 2-3 shift valve described later, and in the 2 range, the 2-3 shift valve is held at the low speed side and the clutch CO and brake +31 of the 2nd gear are connected.
Heline pressure □PI! Therefore, in the second range, the second speed is maintained by the second speed holding valve 216 and the spool 212 regardless of the vehicle speed and the throttle opening.

In FIG. 7, the 2-3 shift valve 240 is
Input port 1-242 connected to 0, low speed output port 244 connected to oil path 100, oil path 246
high-speed side output port 248 connected to the high-speed side output port 248 connected to the oil passage 246 via the orifice 250)
252, a boat 256 connected to an oil passage 254 connected to a clutch C2 to be engaged in third and fourth gears, and a manual valve 46 via an oil passage 206.
The boat 260 connected to the R range port 50 of
, a boat 262 that is connected to the oil passage 132 and receives the governor pressure Pgo, and a second throttle pressure P via the oil passage 144.
th2 is sent) -263, shuttle valve 26
4, the boat 266 receives the modulator pressure in the 2nd range in the oil passage 78 or the detent pressure Pd in the oil passage 168, and the input port I-242 is sent to the output port 2.
44 or 248, the spool 269 is pushed toward the spool 268 by the governor pressure Pgo of the boat 262, and the spring 27 toward the spool 268.
0, a boat 274 that applies the hydraulic pressure of oil F11578 to the pressing member 271 toward the spool 268, and a boat 274 that applies the hydraulic pressure of the oil passage 246 to the stepped portion 276 of the pressing member 271 to press the pressing member 271. Splash 2
It has a boat 278 that biases in the opposite direction to the spring force of 70.

When the second throttle pressure Pth2 is relatively greater than the governor pressure Pgo and the spool 268 is in the second speed position, the input boat 242 is connected to the output port 244. As a result, the line pressure is sent to the hydraulic cylinder of the second speed brake Bl, and the brake Bl is brought into the engaged state.

Further, in this case, the boat 256 is connected to the boat 260, and the oil passage 206 is connected to the drain at the manual valve 46 in the D range, so the third and fourth speed clutches c2 are in the released state. Retained.

m when the governor pressure Pgo is relatively large with respect to the second throttle pressure Pth2 and the spool 268 is in the third speed position.
Input port 242 is connected to output port 248 and port 252 is connected to boat 256. As a result, line pressure Pl is supplied to clutch C2 for third and fourth speeds, and clutch C2 becomes engaged. The supply speed of line pressure Pl to clutch C2 is determined by orifice 25.
Controlled by 0. Also in this case, the output boat 244
plays via boat 280 and oilway 282 = FB
It is connected to the drain of the 2-3 timing valve for I, and the brake 81 for second speed is released.

In the R range, the boat 262 has no pressure Pgo, so the boat 26o is connected to the boat 256. As a result, the line pressure Pl of the oil passage 206 is increased to the boat 260.2.
56, line pressure is supplied to the R range clutch C2. Clutch C2 when R range is shifted to 1-
The rate of supply of line pressure Pl to the boat 260 is determined by an orifice 280 in front of the boat 260.

3-4 shift valve 286 is line pressure PJ in D range
I! An input boat 288 is connected to the oil line 176 to which the oil is sent, an output boat 292 on the low speed side is connected to the oil line 104, an output boat 296 on the high speed side is connected to the oil line 294, and an output boat 296 on the high speed side is connected to the oil line 132. Governor pressure Pgo
The boat 298 is connected to the oil line 144 and the second throttle pressure pth2 is sent to the boat 30.
0, oil path 302 from boat 56 of manual valve 46
A boat 304 to which line pressure Pl is sent during the 3rd range via a boat 304, and an input boat 288 and an output boat 292
Alternatively, it has a spool 306 connected to 296.

When the second throttle pressure Pth2 is relatively larger than the governor pressure Pgo and the spool 306 is in the low speed position, the input port 288 is connected to the output boat 292,
The line pressure Pl is applied to the control valve 9 via the oil passage 104.
8 to boat 106. When the governor pressure PgO is relatively larger than the second throttle pressure Pth2 and the spool 306 is in the high speed side position, the input port 28
8 is connected to the output boat 296, and the fourth continuous brake B
O becomes engaged.

In FIG. 8, an accumulator utilization valve 310 is connected to a boat 312 that is connected to an oil line l16 and receives a first throttle pressure Pthl, and an input that is connected to an oil line 14 and receives a line pressure Pl. Boat 314, oil road 3
16, and a spool 32 that controls the flow cross-sectional area between the input port 314 and the output boat 318 in relation to the second throttle pressure pth2.
It has 0. Brake Bo is connected to 3 through oil passage 204.
-4 Line pressure P from shift valve 286! The accumulator 322 controls the boat 324 to which the line pressure Pl is sent from the oil passage 14, and controls the rise and fall of the hydraulic pressure of the brake BO. The clutch C1 is connected to the oil passage 176, and the accumulator 326 is
Bolt 328 to which line pressure pz is sent from oil passage 14
, and controls the rise and fall of the oil pressure of the clutch C1.

In FIG. 9, the clutch c2 is connected to the 2-
The accumulator 330 is connected to the boat 256 of the third shift valve 240, and controls the boat 332 to which control pressure is sent from the oil line 316, and controls the rise and fall of the oil pressure of the clutch C2.

The 2-3 timing valve 334 is connected to a boat 338 of the second throttle valve 140 via an oil passage 336 (a boat 339 is connected to the boat 338 in relation to the position of the plug 154).
line pressure P7! be guided. ), a boat 342 connected to the boat 34o1 oil line 254,
A boat 348 is connected to the boat 28o of the 2-3 shift valve 2.40 via an oil line 282, a boat 350 is connected to an oil line 316, a drain 352 is connected to the drain via an orifice 354. boat 356
, and a spool 358 that controls the connection between the bow 1-348 and the drain 352. When the boat 348 is shifted up from second gear to third gear, the boat 348
．． It is connected to the second speed brake B1 via the boat 280.244 of the 2-3 shift valve 240, but the third
If the oil pressure of the speed clutch C2 is still low, the boat 34
8 and the drain 352 are disconnected, and the brake B
1 of oil is forced out through orifice 354. When the oil pressure of the clutch C2 becomes sufficiently high, the boat 348 is connected to the drain 352, and the oil in the brake B1 is quickly drained.

The 3-2 kickdown control valve 364 is connected to boats 368 and 370 connected to the boat 244 of the 2-3 shift valve 240 via an oil line 366, and a boat 372 to which governor pressure Pgo is sent via the oil line 132. , a boat 37 connected to brake B1 via an oil passage 374.
6, and boat 376 to boat 368 or 370
It has a spool 378 that connects to the spool 378. During a normal downshift to 2nd gear, the governor pressure Pgo of the boat 372 is low, so the line pressure PJ of the oil 366 is
, 376 to the brake B1. However, if the governor pressure Pgo of boat 372 is high when the boat 372 is shifted down to second gear due to kickdown, boat 3
Since the brake Bl line pressure PJ is sent through 70.376, ie through the orifice 380, the engagement of the brake B1 is delayed. As a result,
A direct downshift from 4th gear to 2nd gear is avoided, and the gear is downshifted to 2nd gear via 3rd gear.

The accumulator 386 has a boat 388 connected to the oil passage 316, and controls the rise and fall of the hydraulic pressure of the brake B1.

In FIG. 10, an automatic transmission fluid torque converter 392 has a pump impeller 394 connected to an engine crankshaft, a stator 396, and a turbine runner 398 connected to a gearing input shaft. . Lock-up clutch 400 is provided in parallel to fluid torque converter 392.

A lock-up signal valve 406 is connected to a boat 408 which is supplied with governor pressure PgO via an oil line 132, and an oil line 29.
Input port 410 connected to high-speed side output boat 296 of 3-4 shift valve 286 via 4, oil line 1
The boat 412 and oil line 41 are connected to the output boat 292 on the low speed side of the 3-4 shift valve 286 via the
4 connected to boat 416, and boat 410
and 416. 3-4 shift valve 286 is in the high speed side position,
Katsuga.

When the vana pressure Pgo exceeds a predetermined value, the line pressure PA of the boat 410 is introduced to the boat 416.

The relay pulp 422 includes a boat 424 connected to the oil line 414 and an input boat 42 connected to the oil line 32.
6. Second throttle valve 140 via oil passage 336
a boat 428 connected to the boat 338 of
A boat 436 connected to the open side of
36 has a spool 438 connected thereto. boat 4
When oil pressure is being sent to the boat 424, the boat 426 is connected to the boat 432 and the lock-up clutch 400 is engaged.

The main parts of the embodiment will be explained.

In the second speed holding valve 216 shown in FIG.
Pushed toward control boat 224 by splash 236, output boat 222 is connected to input boat 218 for the D range. When the I-2 shift valve 184 is in the second speed position, the line pressure Pβ is introduced from the boat 194 of the 1-2 shift valve 184 to the D range input boat 218, and this line pressure P/ is via line 220 to 2-3 shift valve 240.

As a result, when the 2-3 shift valve 240 is in the second speed position, the brake B1 as the second continuous friction engagement device
The line pressure Pl is introduced to the line pressure Pl, and the brake B1 becomes engaged.

In the 2nd range, after the clutch CO as an S friction engagement device for the engine brake is engaged, the oil is passed from the D-2 timing valve 70 to the control boat 224 of the 2nd speed holding valve 216 via the oil passage 78. Modulator pressure Pm2 is derived. As a result, the spool 234 moves against the spring 236, and the output port 222 is connected to the 2-range input boat 2.
32. In addition, in the 2-range, the L-range modulator pressure Pml is not guided from the L-range modulator valve 88 to the input boat 204 in the L-range shift valve 200 via the oil passage 94, so the spool 212 is moved by the spring 214 to the input port 204. The first output port 210 is connected to the input port 208 which is connected to the drain via the manual valve 46 when in the 2nd range, and the second output port 228 is connected to the boat drain. 226. As a result,
The line pressure pz of the oil passage 176 is the boat 226, 228,
2nd speed holding valve 216 and 2-3 shift valve 2
+10 (In the 2nd range, the 2-3 shift valve 240 changes the module pressure Pm for the 2nd range in the side boat 266.
2, it is held in the second gear position. ) is sent to the brake Bl as a second speed frictional engagement device,
Second gear engine braking is achieved.

In the L range, the L range modulator valve 8 is connected to the input port 2o4 in the L range shift valve 200.
8 leads to range modulator pressure PmA, and the spool 212 moves toward the 1-2 shift pulp]84. As a result, in the shift valve 200 for the L range, the first output port 210 is connected to the input port 204, and the second output port 228 is connected to the drain 229, so the brake B2 as a friction engagement device for the L range is connected.
Is the L range modulator pressure Pmj as the engagement pressure? is supplied to the engaged state, and the two-range input port 232 of the second speed holding valve 216 is connected to the drain 229. Therefore, even though the brake B2 is engaged, the second speed holding valve 216 is stuck in the 2 range position, that is, the boat 222 is in the 2 range position.
32, oil will drain from the brake Bl as a frictional engagement device for second gear.
It is possible to avoid a situation where the brake Bl is discharged via the brake B1 and the brake B2 is engaged at the same time.

Although the present invention has been described in terms of embodiments, it will be apparent to those skilled in the art that various modifications can be made within the spirit of the invention as set forth in the claims.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the division of the entire hydraulic control circuit;
FIGS. 2 to 10 are diagrams corresponding to each division in FIG. 1. 200...Shift valve for L range, 21O...First output port, 216...Second speed holding valve, 22
2... Output port, 228... Second output port,
229...Drain, 232...Input boat for 2 ranges.

Claims (1)

[Claims] 1. A low-range friction engagement device that is supplied with a first engagement pressure in a low range and enters an engaged state; A friction engagement device for a low range that is supplied with a second retention pressure and enters an engaged state in a second speed. 2nd continuous frictional engagement device, 2nd continuous frictional engagement device
In the second range, the second speed holding valve is held in a position where it connects the input boat for the second range to the output port, and the second speed holding valve is connected to the friction engagement device for the low range. In the second range, the second engagement pressure is guided to the second output port in the low range. A hydraulic control device for an automatic transmission, comprising: a low range shift valve that guides a first holding pressure to a first output port and connects a second output port to a drain. 2. The hydraulic control device according to claim 1, wherein the second engagement pressure is line pressure. 3 The 2nd speed holding valve has a drive range input port, and in the 2nd speed and above of the drive range, the line pressure is guided from the 1-2 shift valve to the drive range input port, and in the drive range, the line pressure is guided to the drive range input port. 3. The hydraulic control device according to claim 2, wherein the hydraulic control device is held in a position where the boat is connected to the output port.