JP2626360B2 - Hydraulic control device for belt-type continuously variable transmission for vehicles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control apparatus for a belt type continuously variable transmission for a vehicle.

[0002]

2. Description of the Related Art A hydraulic control device for a belt type continuously variable transmission for a vehicle including a pair of primary hydraulic actuators and a secondary hydraulic actuator for respectively changing the effective diameters of a pair of variable pulleys around which a transmission belt is wound. As the first
Second for belt tension control regulated from line oil pressure
A type in which a third line oil pressure adjusted in accordance with a throttle valve opening to act on a line oil pressure and a hydraulic friction engagement device is considered. For example,
That is described in JP-A-2-212656. This hydraulic control device is configured to adjust the first line oil pressure to a value higher by a predetermined pressure than any one of the oil pressure in the primary-side hydraulic actuator and the oil pressure on the higher pressure side of the second line oil pressure. According to this, the first line oil pressure is controlled to a value higher than the oil pressure in the primary side hydraulic actuator and the oil pressure on the high pressure side of the second line oil pressure by a predetermined pressure. There is an advantage that the pressure is adjusted to a low value to reduce the power loss.

[0003]

However, in the first pressure regulating valve of the above-mentioned conventional device, the second line hydraulic pressure is lowered as the speed ratio changes to the minimum value side, that is, the speed-up shift side. Is controlled. In addition, for example, during a rapid deceleration shift, the hydraulic pressure in the primary hydraulic actuator is discharged to the drain, so that it rapidly decreases to a value lower than the second line hydraulic pressure. For this reason, in the rapid deceleration speed change process in which the speed ratio changes rapidly toward the maximum value, in the initial speed-up side region, the required first line oil pressure is not ensured, and the third line pressure using the first line oil pressure as the original pressure is not obtained. Because line pressure cannot be obtained enough,
In some cases, the operation of the frictional engagement device provided integrally with the belt-type continuously variable transmission for power transmission and operated by the third line hydraulic pressure cannot be sufficiently obtained. For example, there has been an inconvenience that slippage occurs because the clutch engagement torque in the planetary gear type forward / reverse switching device decreases. In addition, even at the time of the intermediate deceleration shift by the on / off control of the shift control valve, a state in which the required first line hydraulic pressure is not ensured instantaneously occurs, and the same inconvenience as described above may occur.

The present invention has been made in view of the above circumstances, and has as its object the purpose of the present invention in the case of rapid deceleration shifting.
Another object of the present invention is to provide a hydraulic control device capable of sufficiently obtaining the operation of the friction engagement device to which the third line hydraulic pressure is applied even during an intermediate deceleration shift.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the gist of the present invention is to provide a pair of primary hydraulics for changing the effective diameters of a pair of variable pulleys around which a transmission belt is wound. In order to act on a second line hydraulic and hydraulic friction engagement device for controlling belt tension adjusted from a first line hydraulic in a vehicle belt-type continuously variable transmission having an actuator and a secondary hydraulic actuator. A hydraulic control device of a type that generates a third line hydraulic pressure regulated according to the throttle valve opening degree,
(a) a spool valve operated to regulate the first line hydraulic pressure, and a thrust corresponding to the highest hydraulic pressure among the primary hydraulic pressure in the primary hydraulic actuator, the second line hydraulic pressure, and the third line hydraulic pressure. Plunger means for acting on the spool valve element, and a first pressure regulating valve for generating the first line oil pressure so as to be higher than the highest oil pressure by a predetermined pressure.

[0006]

In this way, in the first pressure regulating valve, the plunger means in the third pressure regulating valve is regulated in accordance with the hydraulic pressure in the primary hydraulic actuator, the second line hydraulic pressure, and the throttle valve opening. Since the line pressure is received and an acting force corresponding to the highest pressure among the hydraulic pressures is applied to the spool valve element, the first pressure regulating valve is provided with a hydraulic pressure in the primary hydraulic actuator, a second line hydraulic pressure, An attempt is made to adjust the hydraulic pressure to a hydraulic pressure value that is higher than the highest hydraulic pressure of the third line hydraulic pressure by a predetermined pressure. For this reason, for example, in the rapid deceleration shift process, in the speed increasing side region, instead of the second line oil pressure adjusted lower according to the gear ratio, the second line oil pressure adjusted according to the throttle valve opening is changed. The acting force acts on the spool valve element, and the first line pressure is regulated by the first pressure regulating valve to a value higher than the third line pressure by a predetermined pressure. Accordingly, the first line oil pressure is sufficiently obtained even in the speed increasing side region, so that the required pressure of the third line oil pressure that uses the first line oil pressure as the base pressure is secured.
For example, even during a rapid deceleration shift or an intermediate deceleration shift by on / off control of the shift control valve, the operation of the friction engagement device can be sufficiently obtained, for example, the slip of the clutch of the forward / reverse switching device is prevented. is there.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a skeleton diagram of a lateral transaxle for an FF vehicle to which a control device according to an embodiment of the present invention is applied, and FIG. 2 is a block diagram showing a configuration example of the control device. In FIG. 1, the power of an engine 10 is supplied by a fluid coupling 12 with a lock-up clutch, a forward / reverse switching device 14, and a belt-type continuously variable transmission (hereinafter referred to as CVT).
The transmission is transmitted to wheels 26 connected to a drive shaft 24 via a transmission 16, an auxiliary transmission 18, a reduction gear device 20, and a differential gear device 22.

The fluid coupling 12 is connected to the engine 1
Pump wheel 30 connected to crankshaft 28
, A turbine impeller 32 rotated by oil from the pump impeller 30, an output shaft 34 connected to the turbine impeller 32 so as to be relatively non-rotatable, and an output shaft 34 via a damper 36. A lock-up clutch 38 is provided. The pump impeller 30 includes a hydraulic pump 40.
Are connected to generate hydraulic pressure for operating the hydraulic actuator of each section. In the above-described fluid coupling 12, when hydraulic oil is supplied to the release-side oil chamber 46 and hydraulic oil in the engagement-side oil chamber 48 is discharged, the lock-up clutch 38 is released. When hydraulic oil is supplied to the chamber 48 and hydraulic oil in the release-side oil chamber 46 is discharged, the lock-up clutch 3
8, the crankshaft 28 and the output shaft 34 are directly connected.

The forward / reverse switching device 14 is a double pinion type planetary gear device which can be selectively switched to a forward gear or a reverse gear according to the operation position of a shift lever 142 described later. It is arranged on the side opposite to the coupling 12. The output shaft 34 of the fluid coupling 12 penetrates the axis of the input shaft 58 of the CVT 16 and protrudes to the opposite side. The planetary gear unit includes a sun gear 50 provided on the output shaft 34 so as to be relatively non-rotatable, and a sun gear 50. A ring gear 52 provided concentrically with 50, a pair of planet gears 54 and 56 meshing with one and the other of the sun gear 50 and the ring gear 52, and rotatably supporting the planet gears 54 and 56. And a carrier 60 which is connected to the input shaft 58 of the CVT 16 so as not to rotate relatively. A multi-plate forward clutch C1 is provided between the sun gear 50 and the carrier 60, and a multi-plate reverse brake B1 is provided between the ring gear 52 and the housing 64. The engagement is controlled by a forward hydraulic actuator 42 and a reverse hydraulic actuator 44, respectively. When the forward clutch C1 is engaged in a state where the reverse brake B1 is released, the output shaft 34 and the carrier 60 are connected to each other so as not to rotate relatively, and the input shaft 58 is rotated integrally with the output shaft 34, and When the clutch C1 is disengaged and the reverse brake B1 is engaged, the rotation of the ring gear 52 is prevented, so that the carrier 6
0 Further, the gear ratio γ _FR (= the rotation speed of the output shaft 34 / the rotation speed of the input shaft 58) = − 1+ (the number of teeth of the ring gear 52) in the direction in which the input shaft 58 is opposite to the output shaft 34, that is, in the direction in which the vehicle moves backward. It is decelerated rotation in Z number of teeth Z _S of _R / sun gear 50).

The CVT 16 includes the input shaft 58 and an output shaft 70 parallel to the input shaft 58.
8. A drive-side variable pulley 72 and a driven-side variable pulley 74 are provided on the output shaft 70, and a transmission belt 76 is wound between the variable pulleys 72 and 74. The variable pulleys 72 and 74 are connected to the input shaft 5
8 and a fixed rotating body 7 fixed to the output shaft 70, respectively.
8 and 80, and movable rotating bodies 82 and 84 provided on the input shaft 58 and the output shaft 70 so as to be movable in the axial direction and not to rotate relatively around the axes, respectively. By being moved in the axial direction by the primary hydraulic actuator 86 and the secondary hydraulic actuator 88 disposed on the rear side, the V-groove width, that is, the hanging diameter (effective diameter) of the transmission belt 76 is changed, Gear ratio γ _{CVT of} CVT16 (=
The rotation speed N _in of the input shaft 58 / the rotation speed N of the output shaft 70
_out ) is changed.

The sub-transmission 18 is constituted by a single pinion type planetary gear unit, and is connected to a sun gear 90 rotatably disposed concentrically with the output shaft 70 and to the output shaft 70 so as to be relatively non-rotatable. A ring gear 92, a sun gear 90 and a planet gear 94 meshed with the ring gear 92, and a carrier 98 rotatably supporting the planet gear 94 and connected to the second output shaft 96 so as to be relatively non-rotatable. Have. A multi-plate high-speed clutch C2 is provided between the sun gear 90 and the carrier 98, and a one-way clutch 102 and a multi-plate low-speed brake B2 are provided between the sun gear 90 and the housing 64. They are provided in series. The engagement of the high speed clutch C2 and the low speed brake B2 is controlled by a high speed hydraulic actuator 106 and a low speed hydraulic actuator 108, respectively. In a low gear stage established by engaging the low-speed stage brake B2, the one-way clutch 1
02 prevents the sun gear 90 from rotating in the opposite direction to the ring gear 92 in the positive torque drive state, but allows the drive wheel 26 to rotate in the same direction as the ring gear 92 in the negative torque drive (engine brake) state. This is to release the power transmission path for transmitting the rotational force to the engine 10 side. Therefore, when the high-speed gear clutch C2 is released and the low-speed gear brake B2 is engaged, the low gear is established. In this state, when the output shaft 70 of the CVT 16 is rotated in a direction for moving the vehicle forward, the carrier 98 and the second output shaft 96 move in the same direction as the rotation direction of the output shaft 70 so that the gear ratio γ _AT (= the output shaft 70 Rotation speed / rotation speed of second output shaft 96) = 1 + (number of teeth Z _{S of} sun gear 90 / number of teeth Z _{R of} ring gear 92). Conversely, when the low-speed gear brake B2 is released and the high-speed gear clutch C2 is engaged, the high gear is established. In this state, the sun gear 90 and the carrier 98 are connected to each other so that they cannot rotate relative to each other, so that the planetary gear device can be rotated integrally, and the second output shaft 96 is connected to the output shaft 70 at the speed ratio γ _AT = 1. Rotated in the same direction. When the vehicle is moving forward, the shift speed can be switched by engaging the high speed clutch C2 while keeping the low speed brake B2 engaged.

The second output shaft 96 is provided with a first gear 110, and the second gear 1 provided on the intermediate shaft 112.
14 is engaged. The intermediate shaft 112 is rotatably disposed around an axis c parallel to the axis b of the second output shaft 96, and the large-diameter gear 11 of the differential gear device 22.
And a third gear 118 meshed with the second gear 6. Second
The gear 114 has a larger diameter than the first gear 110 and the third gear 1
18 has a smaller diameter than the second gear 114,
The reduction gear device 20 is constituted by the gear 110, the second gear 114, and the third gear 118. The differential gear device 22 is supported rotatably about an axis orthogonal to the drive shaft 24 and rotates in unison with the large-diameter gear 116, and engages with the differential small gear 120. A pair of differential gears 12 connected to a drive shaft 24;
2 is provided. Therefore, the power transmitted from the reduction gear device 20 is equally distributed to the left and right drive shafts 24 in the differential gear device 22, and then the left and right front wheels (drive wheels).
26.

In FIG. 2, a throttle sensor 130 provided in an intake pipe (not shown) of the engine 10 supplies a signal representing a throttle valve opening _θth to an electronic control unit 132. Further, for example, an engine rotation sensor 134 provided in an igniter or the like detects a rotation speed N of the engine 10.
A signal representing _e is supplied to the electronic control unit 132. Also,
The input shaft rotation sensor 136 and the output shaft rotation sensor 138 provided on the housing 64 are connected to the input shaft 5 of the CVT 16.
A signal indicating the rotation speed N _in of the output shaft 8 and the rotation speed N _out of the output shaft 70 is supplied to the electronic control unit 132. Further, a vehicle speed sensor 140 provided on the housing 64 for detecting the rotation of the drive shaft 24, that is, the front wheel 26,
A signal corresponding to the vehicle speed SPD is supplied to the electronic control unit 132. Further, the operation position sensor 144 is provided for the shift lever 1.
A signal representing the operation position P _{s of} 42 is supplied to the electronic control unit 132.

The electronic control unit 132 includes a CPU 146, R
The microcomputer 146 includes a so-called microcomputer including an AM 148, a ROM 150, and an interface (not shown). The CPU 146 processes the input signal according to a program stored in the ROM 150 in advance while using a temporary storage function of the RAM 148, The first solenoid valve 152, the second solenoid valve 154, the third solenoid valve 156, and the fourth solenoid are used for control, engagement control of the lock-up clutch 38 of the fluid coupling 12, and shift control of the subtransmission 18. The valve 158, the fifth solenoid valve 160, and the sixth solenoid valve 162 are driven.

FIG. 3 shows the relationship between the operating states of the forward clutch C1, the reverse brake B1, the high speed clutch C2 and the low speed brake B2, which are controlled in relation to the operating position of the shift lever 142, and the shift speed. Is shown. In the figure, when the shift lever 142 is operated in the N (neutral) range, the high speed clutch C2 of the subtransmission 18 is engaged. In the N range, if the forward clutch C1 and the reverse brake B1 of the forward / reverse switching device 14 are released, the CV
Since the transmission of power to T16 is cut off, the operating states of the high speed clutch C2 and the low speed brake B2 of the subtransmission 18 can be either engaged or released, but from the N range to the R (reverse) range. Alternatively, it is only necessary to operate one friction engagement device for switching to the D (drive) range, and the switching control is facilitated.
In the N range, the high speed clutch C2 is engaged as shown in the figure. As shown in the figure, when the shift lever 142 is operated from the N range to the D range, the high speed clutch C2 is released and the low speed brake B2 is engaged after a predetermined time delay from the switching operation. In this way, the sinking of the vehicle is reduced.

The hydraulic control circuit 170 shown in FIG. 2 is constructed as shown in, for example, FIGS. 4, 5, 6, and 7 separately. 4 to 7, the hydraulic pump 40 constitutes a hydraulic source of a hydraulic control circuit 170.
The hydraulic pump 40 sucks in the working oil returned to the oil tank (not shown) through the strainer 174, while sucking the working oil returned through the return oil passage 176 and sends it to the first line oil passage 178. The hydraulic oil in the first line oil passage 178 is leaked to the return oil passage 176 and the clutch pressure oil passage 182 by the relief type first pressure regulating valve 180, so that the first line oil pressure in the first line oil passage 178 is formed. P _r1 is regulated. 184
Is a relief valve for preventing the first line oil pressure _Pr1 from being excessively boosted.

The first pressure regulating valve 180 is a spool valve 1
90, spool valve 1 via spring seat 192
90, a first plunger 196 in contact with the spool valve element 190, a second plunger 198 in contact with the first plunger 196 and having the same diameter as the first plunger 196, and the second plunger 1
98 is provided with a third plunger 199 having the same diameter as that of the third plunger. The spool valve 190 is connected to the first line oil passage 178.
And a port 200c communicating with the clutch oil pressure passage 182 and a drain port 200b communicating with the return oil passage 176. The spool valve 190 includes a first land 202, a second land 204 having a diameter larger than the first land 202, and a first land 202.
Oil chamber 20 for applying feedback pressure to the end face of
6, the first land 202 and the second land 20
4 is open to the atmosphere. A first line oil pressure _Pr1 as a feedback pressure is applied to the oil chamber 206, and the spool valve 190 is urged in the valve opening direction. On the first plunger 196, the second plunger 198, and the third plunger 199 provided coaxially with the spool valve 190, between the first plunger 196 and the second plunger 198, the primary hydraulic actuator 86 is provided. the oil chamber 212 for guiding the oil pressure P _in is provided, the second plunger 1
98 and the third plunger 199,
An oil chamber 214 for introducing a tension control pressure P _belt corresponding to the line oil pressure is provided, and a third plunger 199 is provided.
The end face of which the oil chamber 216 is provided for guiding the engagement hydraulic pressure P _bc to pressure regulated by the engagement hydraulic pressure regulating valve 226 to be described later. First land 202 of spool valve 190
Is A ₁ , the sectional area of the first plunger 196, the second plunger 198, and the third plunger 199 is A ₃ , and the urging force of the return spring 194 is W, and the spool valve 190 has the following formula (1). The first line hydraulic pressure P _r1 is adjusted while being balanced at the position.
The first line oil pressure _Pr1 is equal to the throttle pressure _Pth.
, A throttle valve opening detection valve 220 for regulating the pressure, and a valve pressure regulating valve 22 for regulating the valve pressure _Pv supplied to each solenoid valve
2. A tension control pressure regulating valve 224 for regulating the tension control pressure, an engagement hydraulic pressure regulating valve 2 for regulating an engagement hydraulic pressure _Pbc for engaging the forward clutch C1 and the reverse brake B1.
26.

[0019]

(Equation 1)

[0020] In the first pressure regulating valve 180, the hydraulic pressure P _in the primary side hydraulic actuator 86, the tension control pressure P
Of the three types of hydraulic of _belt and engaging hydraulic pressure P _bc, the primary side hydraulic actuator 86 hydraulic P _in the tension control pressure P
_belt and engagement operating oil pressure _Pbc , the first
A plunger 196 spaced is between the second plunger 198 thrust by the hydraulic pressure P _in the above primary side hydraulic actuator acts on the valve closing (pressure increase) direction of the spool valve element 190, but the tension control pressure P _belt primary Side hydraulic actuator 86
If higher than the inner pressure P _in and the engaging hydraulic pressure P _bc, since the first plunger 196 with between the second plunger 198 and the third plunger 199 is disengaged and the second plunger 198 abuts, The thrust caused by the tension control pressure P _belt acting on the oil chamber 214 is the spool valve 1
Acts in the closing direction 90, the engagement hydraulic pressure P _bc hydraulic in the primary side hydraulic actuator 86 P _in and the tension control pressure P
If it is higher than the _belt , the first plunger 196, the second
Since the plunger 198 and the third plunger 199 are in contact with each other, the thrust by the engagement operating oil pressure _Pbc acting on the end face of the third plunger 199 causes the spool valve 1
90 acts in the valve closing direction. That is, the second plunger 198 and the third plunger 199 provide the spool valve with a thrust corresponding to the highest hydraulic pressure among the hydraulic pressure _{Pin in} the primary hydraulic actuator 86, the tension control pressure _Pbelt, and the engagement hydraulic pressure _Pbc. This corresponds to the plunger means acting on the child 190. As a result, the first line hydraulic pressure P
_r1 is adjusted to a value higher than the highest oil pressure among the oil pressure _{Pin in the} primary side hydraulic actuator, the tension control pressure P _belt and the engagement operating oil pressure _{Pbc by} a predetermined margin value, and the power for generating the oil pressure Losses are minimized.

The throttle valve opening detection valve 220 is engaged with a throttle cam 230 interlocked with a throttle valve rotated by operation of an accelerator pedal (not shown) and a cam surface of the throttle cam 230. A plunger 232 whose axial position is changed in relation to the rotation angle of 230, a spool valve 234 for adjusting the throttle pressure P _th , and a spring 236 for urging the spool valve 234 in the valve opening direction. Have.
The spool valve element 234 is a valve closing valve that is generated based on the thrust in the valve opening direction applied from the plunger 232 via the spring 238, the thrust in the valve closing direction of the spring 236, and the throttle pressure P _th acting as feedback pressure. by the direction of the thrust is brought into a position so as to balance, the first line pressure P _r1 vacuo, to generate a larger throttle pressure P _th with the throttle valve opening theta _th.

The valve pressure regulating valve 222 is positioned such that the thrust in the valve opening direction applied from the spring 240 and the thrust in the valve closing direction generated based on the valve pressure _Pv acting as feedback pressure are balanced. A spool valve 242 is provided to reduce the pressure of the first line oil pressure P _r1 which is the original pressure, thereby generating a constant valve pressure P _v . The valve pressure _Pv is supplied to the third solenoid valve 156, the fourth solenoid valve 158, and the fifth solenoid valve 160, respectively. The third solenoid valve 156 and the fourth solenoid valve 158 include an input port to which the valve pressure _Pv is supplied, a drain port,
An output port, wherein the spherical valve element closes the drain port and communicates between the input port and the output port, and the spherical valve element closes the input port and communicates between the drain port and the output port. It is a 3 port 2 position valve that can be switched. The fifth solenoid valve 160
Has a spool valve element 246 biased in the valve closing direction by the spring 244 and the feedback pressure, and a linear solenoid 248 biasing the spool valve element 246 in the valve opening direction by a thrust corresponding to the exciting current. It is configured to generate a signal pressure P _lin that increases according to the exciting current.

[0023] The tension control pressure regulator valve 224, a first line oil path 178 and the tension control pressure P for guiding the first line pressure P _r1
The spool valve 262 opens and closes the tension control pressure oil passage 260 that guides the _{belt. The} return spring 266 applies a biasing force in the valve opening direction to the spool valve 262 via the spring seat 264. There is provided a plunger 268 that comes into contact with the valve to apply a biasing force in the valve opening direction. Further, a first land 270 and a second land 272 whose diameters increase in order are formed at the shaft end of the spool valve element 262 in order. A tension control pressure P _belt as a feedback pressure is provided between the first land 270 and the second land 272.
There is provided an oil chamber 276 through which the air is introduced through the throttle 274. Also, the first land 270 of the spool valve element 262
An oil chamber 278 to which the signal pressure P _lin output from the fifth solenoid valve 160 is applied is provided on the end face side, and the spool valve element 262 is _biased in the valve closing direction based on the speed ratio γ _cvt . It is supposed to be. The plunger 268 includes
A third land 280 and a fourth land 282 of decreasing diameter are provided in order from the spool valve element 262 side. The end face of the fourth land 282 has the oil chamber 284 is provided for exerting a throttle pressure P _th, so the spool valve element 262 is urged in the valve opening direction by the throttle pressure P _th I have. Further, between the third land 280 and the fourth land 282, an oil chamber 286 to which a signal pressure P _sol4 output from the fourth solenoid valve 158 is applied is provided, and this signal pressure P _sol4 is generated. In this case, the spool valve element 262 is urged in the valve opening direction and the tension control pressure P
_{The belt} is designed to be raised to a predetermined pressure. Therefore, the pressure receiving area of the first land 270 is A ₄ , the cross-sectional area of the second land 272 is A ₅ , the cross-sectional area of the third land 280 is A ₆ , the pressure receiving area of the fourth land 282 is A ₇ , and the return is performed. Assuming that the urging force of the spring 266 is W, the spool valve element 262 is balanced at a position where the equation 2 is satisfied. That is, when the spool valve element 262 is moved according to Equation 2, the first line hydraulic pressure _Pr1
Is reduced to generate a tension control pressure P _belt , which is supplied to the hydraulic actuator 88 on the secondary side. As described above, the tension control pressure P _belt is basically adjusted based on the throttle valve opening θ _th and the speed ratio γ _cvt corresponding to the output torque of the engine 10, so that the tension of the transmission belt 76 is
That is, the clamping pressure is controlled to a necessary and sufficient value, the power loss is reduced, and the durability of the transmission belt 76 is enhanced.

[0024]

(Equation 2)

The engagement hydraulic pressure regulating valve 226 is configured to open and close a spool valve 292 between the first line oil passage 178 and the engagement hydraulic oil passage 290 and a spool valve 292 via a spring seat 294. A spring 296 that biases in the valve opening direction and a plunger 298 that abuts on the spool valve element 292 are provided. The spool valve element 292 is provided with a first land 300 and a second land 302 having a larger diameter in order from the end, and an engagement between the first land 300 and the second land 302 is provided. An oil chamber 304 in which the dynamic oil pressure _Pbc acts as a feedback pressure is provided. Further, the plunger 298 is provided with a third land 306 and a fourth land 308 having a smaller diameter sequentially from the spool valve element 292 side.
06 and the fourth land 308, the shift lever 1
When the valve 42 is operated to the R range, the manual valve 310
An oil chamber 312 which R range pressure P _R is supplied to the output from the
Is provided. Further, an oil chamber 314 is provided for receiving the throttle pressure P _th acting on the end face of the fourth land 308. Therefore, the spool valve 2
92, so that the opening direction of the thrust by the valve opening direction of the thrust and the spring 296 based on the throttle pressure P _th or throttle pressure P _th and R range pressure P _R, the closing direction of the thrust based on the feedback pressure is balanced And the engagement hydraulic pressure P having a magnitude corresponding to the throttle pressure P _th
Generate _bc . Also, when the R range pressure P _R is supplied, it increases its engagement hydraulic pressure P _bc only predetermined pressure. Thus, the engagement hydraulic pressure P _bc, as well is increased in accordance with the output torque of the throttle pressure P _th, that is, to the engine 10, the shift lever 142 is increased further by a predetermined pressure therefrom when operated to the R-range, the forward The clutch C1, the reverse brake B1, the high speed clutch C2, or the low speed brake B2 is engaged with a necessary and sufficient thrust. The engagement operating oil pressure _Pbc is also supplied to the oil chamber 216, the first solenoid valve 152, the second solenoid valve 154, and the sixth solenoid valve 162 of the first pressure regulating valve 180 described above. The sixth solenoid valve 162 is configured similarly to the third solenoid valve 156 and the fourth solenoid valve 158 described above.
On the other hand, the first solenoid valve 152 and the second solenoid valve 154 open the downstream side of the throttles 318 and 320 to the drain when in the off state, but open the downstream side from the throttles 318 and 320 when in the on state. Each is a two-port two-position valve with an engagement operating oil pressure _Pbc .

The first solenoid valve 152 is provided with a shift direction switching valve 330 for switching the direction of change of the gear ratio of the CVT 16.
, And the second solenoid valve 154 controls the shift speed control valve 332 for controlling the speed ratio change speed of the CVT 16. The shift direction switching valve 330 includes a first input port 334 communicating with the first line oil passage 178, a second input port 338 communicating with the first line oil passage 178 via a medium throttle 336, and a relatively small throttle 340. A first output port 344 communicating with the primary hydraulic actuator 86 via a relatively large throttle 342, a second output port 348 communicating with the input port 346 of the shift speed control valve 332, and a drain port 350; Allows communication between the first input port 334 and the first output port 344 and communication between the second input port 338 and the second output port 348, respectively.
A spool valve 352 for communicating between the valve 8 and the drain port 350 and a spring 354 for urging the spool valve 352 toward the off position are provided. Therefore, when the first solenoid valve 152 is turned off, the spool valve element 352 is positioned at the off position, and hydraulic oil is supplied into the hydraulic actuator 86 on the primary side so that the CVT 1
6 is changed in the speed increasing direction. Conversely, the first solenoid valve 1
52 is turned on, the spool valve element 352 is positioned at the on position, and the primary hydraulic actuator 8
The hydraulic oil in 6 is discharged from the drain port 350, and the CVT 16 is changed in the deceleration direction.

The shift speed control valve 332 communicates between the input port 346, an output port 356 communicating with the primary hydraulic actuator 86, and between the input port 346 and the output port 356 in the on position, and in the off position. It includes a spool valve element 358 to block, and a spring 360 which urges the spool valve element 358 to the off position at. Therefore, the second solenoid valve 1
When the valve 54 is turned off, the spool valve element 358 shuts off the connection between the input port 346 and the output port 356. Therefore, when the first solenoid valve 152 is in the on state, the slow deceleration mode is set, and the first solenoid valve 152 Is in the off state, the mode is the slow acceleration mode. When the second solenoid valve 154 is turned on, the spool valve element 358 is connected to the input port 34.
6 and the output port 356, the first
When the solenoid valve 152 is in the off state, the mode is the rapid acceleration mode, and when the first solenoid valve 152 is in the on state, the mode is the rapid deceleration mode. FIG. 8 shows the relationship between the combination of the operation states of the first solenoid valve 152 and the second solenoid valve 154 and the shift mode of the CVT 16 obtained by the combination.

The manual valve 310 includes a spool valve element 364 interlocked with the shift lever 142, a first port 366, a second port 368, and a third port 370. , the engaging hydraulic pressure P _bc whose pressure regulated by the engaging hydraulic pressure regulating valve 226 is supplied as a source pressure. From the first port 366,
The shift lever 142 is D range, S range, the forward range pressure P _F is output when it is operated to the forward range such as L range, from the third port 370, the shift lever 14
2 is the reverse range pressure P _R is output when it is operated to the R range.

[0029] The forward range pressure P _F output from the first port 366, through aperture 374, or aperture 37
6 and the shift timing valve 378 are supplied to the forward hydraulic actuator 42. The spool valve element 380 of the shift timing valve 378 moves against the spring 382 in response to an increase in the hydraulic pressure in the hydraulic actuator 42 for forward movement, and suppresses the inflow flow rate. When the shift lever 142 is operated to a range other than the forward range, the hydraulic oil in the forward hydraulic actuator 42 is released from the check valve 38.
4 and drain through the manual valve 310 quickly.

Further, when the shift lever 142 is operated to the R range, the reverse range pressure P _R that is output from the third port 370, the oil chamber 31 of the engagement hydraulic pressure regulating valve 226
2 and the reverse inhibit valve 37
2 and the throttle 386 are supplied to the reverse hydraulic actuator 44. Conversely, when the shift lever 142 is operated to a range other than the R range, the hydraulic oil in the reverse hydraulic actuator 44 is quickly discharged to the drain through the check valve 387, the reverse inhibit valve 372, and the manual valve 310, reverse range P _R is set to atmospheric pressure.

The reverse inhibit valve 372 has a first land 388, a second land 390 larger in diameter than the first land 388, and a third land 392 having the same diameter as the first land 388.
A spool valve 394 that opens and closes between the third port 370 and the reverse hydraulic actuator 44 by 0, and a spring 39 that urges the spool valve 394 in the valve opening direction.
6 and a plunger 398 that contacts the spool valve element 394 in order to bias the spool valve element 394 in the valve opening direction. Also,
The plunger 398 has the same cross-sectional area as the cross-sectional area difference between the first land 388 and the second land 390. A signal pressure P _sol3 generated when the third solenoid valve 156 is in the ON state (the engagement state of the lock-up clutch 38) is applied to the end surface of the first land 388, and the first land 388 and the third land 388 are connected to the first land 388. reverse range pressure P _R is allowed to act between the second land 390. Further, the engagement operating oil pressure _Pbc is constantly applied to the end face of the plunger 398, and the spool valve element 394 and the plunger 398
The hydraulic pressure in the reverse hydraulic actuator 44 is made to act between them. Therefore, the spool by thrust and brake engagement pressure P _bc be urged by reverse range pressure P _R to spool 394 in the valve opening direction valve member 394
When the shift lever 142 is operated to the R range (reverse range), the spool valve element 394 is moved to the valve-opening position by the biasing force of the spring 396. When it is positioned and the signal pressure P _sol3 is applied, the spool valve element 394 is positioned in the valve closing direction, that is, in the inhibit position.
Therefore, during forward running in which the lock-up clutch 38 is engaged, the signal pressure P _sol3 is applied, and when the shift lever 142 is operated to the R range (reverse range), the spool The valve 394 is moved to the valve closing position, and the reverse hydraulic actuator 44 is connected to the drain port 4 of the reverse inhibit valve 372.
00 and the operation of the reverse brake B1 is blocked. However, when the reverse range pressure P _R is allowed to act on the reverse hydraulic actuator 44 once, so that the reverse range pressure P _R is to generate a thrust in the opening direction of the spool valve element 394, it is even the signal pressure P _SOL3 action The spool valve 394 is held at the valve open position even if the operation is performed.

The forward hydraulic actuator 42 and the reverse hydraulic actuator 44 have a throttle pressure P _th
Accumulator 402 which is acted as back pressure
And 404 are connected respectively, and as the transmission torque increases, the forward hydraulic actuators 42
In addition, the rise of the hydraulic pressure in the reverse hydraulic actuator 44 is moderated, and the engagement of the forward clutch C1 and the reverse brake B1 is smoothened.

The high-speed clutch C2 and the low-speed brake B2 of the subtransmission 18 are switched by a sixth solenoid valve 162 between a C2 control valve 410 and a B2 control valve 412.
It can be switched by. The C2 control valve 410 restricts an output port 414 communicating with the high-speed stage hydraulic actuator 106 by an engagement operating oil pressure _Pbc.
Port 416 and hydraulic oil supplied through
A spool valve 420 that selectively communicates with a drain port 418 for draining through the spool, a spring 422 that urges the spool valve 420 toward the engagement side position, and a housing that accommodates the spring 422 _{And an} oil chamber 424 for receiving the signal pressure P _sol6 from the sixth solenoid valve 162.
And an oil chamber 426 connected to the low-speed stage hydraulic actuator 108 via a throttle 425 to apply a hydraulic pressure in the low-speed stage hydraulic actuator 108 to an end face of the spool valve 420 opposite to the spring 422 side. And Therefore, in the C2 control valve 410, the oil chamber 42
4 and the oil chamber 426 are both at atmospheric pressure, or when the signal pressure P _sol6 and the oil pressure in the low-speed stage hydraulic actuator 108 are supplied to the oil chamber 424 and the oil chamber 426, respectively, the spool valve element 420 The high-speed gear clutch C2 is engaged by the high-speed hydraulic actuator 106 while being positioned on the engagement side. However, when the oil pressure in the low-speed stage hydraulic actuator 108 is supplied to the oil chamber 426 in a state where the oil chamber 424 is at atmospheric pressure, the spool valve 420 is moved to the non-engagement side position (the off side position in FIG. 7). After being positioned, the hydraulic oil in the high speed gear hydraulic actuator 106 is drained, and the high speed gear clutch C2 is released. Incidentally, the accumulator 428 and brake engagement pressure P _bC or throttle pressure P _th is supplied as a back pressure through the B2 control valve 412 is intended to smooth the engagement of the high-speed-stage clutch C2.

The B2 control valve 412 is connected to the engagement operating pressure P
first port _{430 bC} is supplied, a second port 432 which throttle pressure P _th is supplied, a drain port 434, a third port 436, the forward range pressure P _f is supplied that is connected to the low speed stage hydraulic actuator 108 4th port 4
38, the fifth connected to the back pressure chamber of the accumulator 428
Port 440 and the fifth port 440 to the first port 4
30 or the second port 432, and the spool valve 442 for selectively switching the third port 436 to the drain port 434 or the fourth port 438, and the spool valve 442 to the engagement side position. Spring 444 biasing toward the
An oil chamber 446 that receives the oil pressure in the forward hydraulic actuator 42 and receives the oil pressure to _{apply a} signal pressure P _sol6 to the end face of the spool valve element 442 opposite to the spring 444. It has. Therefore, in the B2 control valve 412, when both the oil chamber 446 and the oil chamber 448 are at the atmospheric pressure,
46 and oil chamber 448 are provided with forward hydraulic actuator 42.
When the internal hydraulic pressure and the signal pressure P _sol6 are supplied, respectively, the spool valve 420 is positioned on the engagement side, and the low-speed gear brake actuator 108 engages the low-speed gear brake B2. However, when the signal pressure P _sol6 is supplied to the oil chamber 448 while the oil chamber 446 is at atmospheric pressure, the spool valve element 442 is positioned at the non-engagement side position, and The hydraulic oil is drained, and the low-speed gear brake B2 is released.

Next, the clutch oil pressure P _cl in the clutch pressure oil passage 182 is adapted to be pressure regulated according to the throttle pressure P _th by a clutch pressure regulating valve 450. The clutch oil pressure P _cl is related to the engagement pressure of the lock-up clutch 38, but the hydraulic oil in the clutch pressure oil passage 182 passes through the throttle 453 to the sliding portion of the transmission belt 76, the bearing portion, and the planetary gear. Meshing part, differential gear device 2
2 and the like as lubricating oil. In addition, the hydraulic oil discharged from the relief port 455 of the clutch pressure regulating valve 450 is also pressure-fed as lubricating oil. The clutch pressure regulating valve 450 includes a spool valve element 452 for allowing the hydraulic oil in the clutch pressure oil path 182 to escape to the return oil path 176, a spring 454 for urging the spool valve element 452 in the valve closing direction, A plunger 456 which receives the throttle pressure P _th and transmits a thrust in the valve closing direction based on the throttle pressure P _th to the spool valve element 452, and a clutch oil pressure P as a feedback pressure for applying a thrust in the valve opening direction to the spool valve element 452.
_An oil chamber 458 for receiving _cl is provided.

To control the engagement and release of the lock-up clutch 38, a lock-up relay valve 460 switched by a third solenoid valve 156 and a fourth solenoid valve 15
A lock-up control valve 462 that is switched by the control unit 8 is provided. The lock-up relay valve 460 is connected to the clutch oil pressure P _cl via a drain port 464 and a check valve 466.
Is supplied to the first port 468, the second port 470, the third port 472, the fourth port 474, and the fifth port 47.
6, a drain port 478, a spool valve element 480 for switching between the ports, and the spool valve element 4
And a spring 484 for urging the 80 toward the oil chamber 482 side. Therefore, the signal pressure P from the third solenoid valve 156
_{In a state} where _sol3 is not supplied to the oil chamber 482, the spool valve element 480 is positioned toward the oil chamber 482, so that the first port 468 and the second port 470, the third port 472 and the fourth port 474, and the fifth port 476 are provided. And drain port 47
8 are communicated with each other. Conversely, the third solenoid valve 15
In a state where the signal pressure P _SOL3 is supplied to the oil chamber 482 from 6, the spool valve element 480 is caused to position the oil chamber 482 side, the drain port 464 and second port 470, a first
The port 468 communicates with the third port 472, and the fourth port 474 communicates with the fifth port 476.

The lock-up control valve 462 includes a check valve 46
First port 4 to which clutch hydraulic pressure _Pcl is supplied via port 6
90, second port 470 of lock-up relay valve 460
Port 492 connected to the third port 49 connected to the fifth port 476 of the lock-up relay valve 460.
4. Fourth port 496 connected to third port 472 of lock-up relay valve 460, fluid coupling 1
A fifth port 498 connected to the second release-side oil chamber 46, a sixth port 500 connected to the engagement-side oil chamber 48 of the fluid coupling 12, a spool valve element 502 for switching between these ports, And a spring 506 for urging the spool valve 502 toward the oil chamber 504. Therefore, when the signal pressure P _sol4 from the fourth solenoid valve 158 is not supplied to the oil chamber 504, the spool valve element 50
2 is located on the oil chamber 504 side, so the second port 4
92 and the fifth port 498, and the fourth port 496 and the sixth port 500, respectively. Conversely, when the signal pressure P _sol4 from the fourth solenoid valve 158 is supplied to the oil chamber 504, the spool valve 502 is positioned toward the spring 506, so that the first port 490 and the fifth port 4
98, the third port 494 and the sixth port 500 are communicated with each other.

Therefore, when the third solenoid valve 156 is turned off in the off state of the fourth solenoid valve 158, the clutch oil pressure _Pcl is changed to the first port 468, the second port 470,
At the same time as being applied to the release-side oil chamber 46 via the second port 492 and the fifth port 498, the engagement-side oil chamber 48
Hydraulic oil in the sixth port 500, fourth port 496, third port 472, fourth port 474, oil cooler 51
0 through the lock-up clutch 38
Is released. At this time, part of the hydraulic oil discharged from the engagement side oil chamber 48 is also drained through the oil cooler 510. An upstream side of the oil cooler 510 is provided with a cooler bypass valve 512 for draining without passing through the oil cooler 510 when the pressure of the hydraulic oil discharged from the engagement side oil chamber 48 exceeds a predetermined value. ing. Further, when the third solenoid valve 156 is turned on while the fourth solenoid valve 158 is on, the clutch oil pressure _Pcl is changed to the first port 49.
At the same time, the hydraulic oil in the engagement side oil chamber 48 is applied to the release side oil chamber 46 via the fifth port 498 and the sixth port 500, the third port 494, the fifth port 476, and the fourth port. 474 and the oil cooler 510 are drained, and the lock-up clutch 38 is released. There are two modes for releasing the lock-up clutch 38.

When the fourth solenoid valve 158 is turned on, the third
When the solenoid valve 156 is turned off, the clutch oil pressure P _cl
Is applied to the release-side oil chamber 46 via the first port 490 and the fifth port 498, and the hydraulic oil in the engagement-side oil chamber 48 is supplied to the sixth port 500, the third port 494, and the fifth port 494.
The lock-up clutch 38 is quickly drained through the port 476 and the drain port 478.
In this case, in addition to the hydraulic oil in the engagement side oil chamber 48 flowing out to the drain without passing through the oil cooler 510, the signal pressure P _sol4 from the fourth solenoid valve 158 is used as the tension control pressure regulating valve. 224 is applied to the oil chamber 286 to control the tension P
with _belt is enhanced, since the tension control pressure P _belt first line pressure P _r1 may be enhanced is applied to the oil chamber 214 of the first pressure regulating valve 180, a throttle to source pressure the first line pressure P _r1 The throttle pressure P _th output from the valve opening detection valve 220 is also increased, and the clutch pressure regulating valve 450 is increased.
Since the clutch oil pressure P _cl is increased to be pressure regulated in is the lock-up clutch 38 is rapidly released. Such a rapid release mode of the lock-up clutch 38 is selected when the CVT 16 executes the rapid deceleration shift in connection with the sudden stop of the vehicle.

When the fourth solenoid valve 158 is in the off state, the third
When the solenoid valve 156 is turned on, the clutch oil pressure P _cl
Are the first port 468, the third port 472, and the fourth port 4
96, while being acted on the engagement side oil chamber 48 via the sixth port 500, the hydraulic oil in the release side oil chamber 46
Port 498, second port 492, second port 470,
It is drained through the drain port 464, and the lock-up clutch 38 is engaged.

In the electronic control unit 132, the CVT 16
Gear ratio control, engagement control of the lock-up clutch 38,
Sudden deceleration control of CVT 16, tension control pressure control, auxiliary transmission 1
8 is executed. In the gear ratio control of the CVT 16, for example, the first operation is performed so that the engine 10 operates along an optimal curve on which fuel efficiency and drivability are obtained.
The electromagnetic valve 152 and the second electromagnetic valve 154 are driven to adjust the speed ratio γ _CVT . Lock-up clutch 3
In the engagement control of No. 8, for example, it is determined whether or not the vehicle is in the engagement region based on the vehicle speed SPD and the throttle valve opening _θth based on a relationship stored in advance. The third solenoid valve 156 is turned on with the fourth solenoid valve 158 turned off, and if it is determined that the area is in the release area, the third solenoid valve 156 is turned off with the fourth solenoid valve 158 turned off. Turned off. Further, in the rapid deceleration control of the CVT 16 prior to the sudden stop of the vehicle, the first solenoid valve 152 and the second solenoid valve 154 are both turned on to enter the rapid deceleration shift mode, and the third solenoid valve 156 is turned off. And the fourth solenoid valve 158 is turned on, whereby the lock-up clutch 38 is promptly released.
In the tension control pressure control, for example, the tension control pressure P _{belt applied} to the secondary-side hydraulic actuator 88 is stored in advance so as to obtain a target pressure that is small within a range in which the transmission belt 76 does not slip. The fifth solenoid valve 160 is controlled based on the relationship. In the speed change control of the subtransmission 18, for example, as described in Japanese Patent Application Laid-Open No. 61-241561 or Japanese Patent Application Laid-Open No. 62-137239, the actual throttle valve opening is determined based on a relationship stored in advance. The gear to be switched is determined based on _θth and the gear ratio γ _CVT or the vehicle speed SPD. If the determination result is a high gear, the sixth solenoid valve 162 is turned on. 162 is turned off.

As described above, according to this embodiment, as shown in FIG. 5, in the first pressure regulating valve 180, the second plunger 198 and the third plunger 199 constituting the plunger means of the present invention are primary The operating force corresponding to the highest hydraulic pressure among the hydraulic pressure P _{in in} the side hydraulic cylinder, the tension control pressure P _belt , and the engagement hydraulic pressure P _bc corresponding to the third line hydraulic pressure of the present invention is used to close the spool valve element 190. Acting in the valve direction, the first pressure regulating valve 180 is set to a hydraulic pressure value higher by a predetermined pressure than the highest hydraulic pressure among the primary hydraulic pressure _{in the} hydraulic actuator _Pin , the tension control pressure _Pbelt, and the engagement hydraulic pressure _Pbc. Try to regulate pressure. For this reason, as shown in FIG. 9, for example, in a process _in which the hydraulic pressure Pin in the primary hydraulic actuator 86 is discharged to the drain and the speed is rapidly reduced, in the initial speed increasing side region, the hydraulic pressure becomes lower according to the speed ratio γ _CVT. Instead of the adjusted tension control pressure P _belt , the acting force corresponding to the engagement operating oil pressure P _bc adjusted according to the throttle opening θ _th acts on the spool valve element 190, and the first line oil pressure P _{belt r1} is regulated by the first pressure regulating valve 180 to a value higher than the engagement operating oil pressure _Pbc by a predetermined pressure as shown by a three-dot chain line in FIG. Accordingly, the first line oil pressure P _r1 is sufficiently obtained also in the speed increasing side region, so that the necessary pressure of the engagement operating oil pressure P _{bc using} the first line oil pressure P _r1 as the base pressure is secured. The forward clutch C1 of the forward / reverse switching device 14 even during a rapid deceleration shift
Is prevented from slipping.

[0043] Incidentally, the hydraulic pressure P _in and the tension control pressure P _belt of the first line pressure P _r1 is the primary hydraulic actuator
In the conventional hydraulic control device of the type controlled to a value higher than the hydraulic pressure on the high pressure side by a predetermined pressure, the first
Line pressure is being pressure regulated as P _r1 'shown in solid line in FIG. 10, for example at the time of rapid deceleration speed, two-dot chain line in FIG. 9 since the hydraulic pressure P _in the primary side hydraulic actuator is discharged into the drain since less than the tension control pressure P _belt as the first line hydraulic pressure as P _r1 'shown in solid line in FIG. 9, than low controlled tension control pressure P _belt at the minimum value side gear ratio gamma _cvt The pressure is adjusted higher by a predetermined pressure. For this reason, the first line oil pressure _Pr1 cannot be sufficiently obtained in the initial speed increasing side region in which the speed ratio γ _CVT changes from the speed increasing side to the speed decreasing side, and the third line oil pressure is required in connection with this. I couldn't get enough.

In this embodiment, for example, FIG.
Even during the intermediate deceleration shift shown in (b), a state where the first line oil pressure _Pr1 is not sufficiently ensured momentarily continuously occurs in connection with the on / off control of the second solenoid valve 154, and the third line oil pressure Is prevented from being instantaneously lowered, the forward clutch C1 is suitably operated even during an intermediate deceleration shift.

Further, in this embodiment, since the decrease in the first line pressure P _r1 during rapid deceleration gear is prevented, the clutch oil pressure P _cl of the first line pressure P _r1 source pressure in relation to this It is prevented from lowering. Therefore, there is an advantage that the release operation of the lock-up clutch 38 can be suitably obtained even during the rapid deceleration shift.

Further, in the present embodiment, the decrease in the first line hydraulic pressure _Pr1 is suppressed irrespective of the decrease _in the hydraulic pressure Pin in the primary hydraulic actuator that occurs during a rapid deceleration shift or an intermediate deceleration shift. As a result, the margin pressure for setting the first line oil pressure _Pr1 high can be suppressed to the minimum necessary in consideration of the decrease _in the oil pressure Pin in the primary hydraulic actuator. Therefore, the power loss of the hydraulic pump 40 is reduced, and the fuel efficiency of the vehicle is improved.

Next, another embodiment of the present invention will be described. In the following description, the same parts as those in the above-described embodiment are denoted by the same reference numerals, and description thereof will be omitted.

In the above-described embodiment, the second plunger 198 and the third plunger 19
Hydraulic pressure acting on the spool valve element 190 by 9, the primary side hydraulic actuator 86 in the hydraulic P _in, tension control pressure P
had been the most high hydraulic pressure of the _belt and the engaging hydraulic pressure P _bc, hydraulic P _in the primary side hydraulic actuator 86 in the present embodiment, the most high pressure of the tension control pressure P _belt and the clutch oil pressure P _cl It is configured to have a hydraulic pressure. That is, FIG. 11, FIG. 12, FIG.
, The oil chamber 21 on the end face of the third plunger 199
Clutch oil pressure P _cl is supplied with pressure regulated by the clutch pressure regulating valve 450 in place of the engagement hydraulic pressure P _bc to 6. This clutch oil pressure P _{cl is} also used as the clutch pressure regulating valve 450.
Thus, the pressure is adjusted in accordance with the throttle pressure P _th , and shows a constant value irrespective of a change in the speed ratio γ _CVT . Thus, for example, in the initial acceleration side region of rapid deceleration speed process, the speed ratio γ instead of the low pressure-regulated tension control pressure P _belt according to _{the CVT} the clutch oil pressure P thrust corresponding to _cl spool valve Pressure increasing direction of the child 190,
That is, it acts in the valve closing direction, and the first line oil pressure _Pr1 is adjusted to a value higher than the clutch oil pressure _Pcl by a predetermined pressure, so that the same effect as in the above-described embodiment can be obtained.
In this embodiment, the clutch hydraulic pressure _Pcl is set to the third
Compatible with line hydraulics.

While the embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be embodied in other forms.

[0050] For example, in the above embodiment, as the third line pressure the regulating pressure regulating valve pressure regulated according to the throttle valve opening theta _th, engagement hydraulic pressure regulating valve 226 or the clutch pressure regulating valve 450 is used the Rukoto, the oil chamber 216 of the first pressure regulating valve 180 is engaging hydraulic pressure P _bc or the clutch pressure P _cl has been action, to act on the oil chamber 216 of the first line pressure P _r1 as source pressure By newly providing a dedicated pressure regulating valve for regulating the hydraulic pressure, a hydraulic pressure other than the above may be applied to the oil chamber 216. In short, the hydraulic pressure adjusted according to the throttle valve opening to act on the hydraulic friction engagement device is applied to the first pressure regulating valve 180.
It is only necessary that a pressure regulating valve acting on the spool valve element 190 is provided.

In the above-described embodiment, the auxiliary transmission 18 is provided after the CVT 16, but the present invention is also applicable to a power transmission device provided before the CVT 16.

In the above embodiment, the auxiliary transmission 18 has two forward gears, but may have three or more gears.

Although not specifically exemplified, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram of a vehicle power transmission device to which the embodiment of FIG. 2 is applied.

FIG. 2 is a block diagram illustrating a configuration of a control device according to an embodiment of the present invention.

FIG. 3 is a table illustrating a relationship between an operation position of a shift lever and a gear in the power transmission device of FIG. 1;

FIG. 4 is a part of a hydraulic circuit diagram showing a configuration of the hydraulic control device in FIG. 2;

FIG. 5 is a part of a hydraulic circuit diagram showing a configuration of the hydraulic control device in FIG. 2;

FIG. 6 is a part of a hydraulic circuit diagram showing a configuration of the hydraulic control device of FIG. 2;

FIG. 7 is a part of a hydraulic circuit diagram showing a configuration of the hydraulic control device of FIG. 2;

FIG. 8 is a diagram showing a relationship between a control deviation ΔN _in and a shift mode _in feedback control of the continuously variable transmission of FIG. 1;

9 is a diagram showing output characteristics of the first pressure regulating valve of FIG. 5 during a rapid deceleration shift.

FIG. 10 is a diagram showing output characteristics of a first pressure regulating valve in a conventional hydraulic control device in a steady state.

FIG. 11 is a view corresponding to FIG. 4 in another embodiment of the present invention.

FIG. 12 is a view corresponding to FIG. 5 in another embodiment of the present invention.

FIG. 13 is a view corresponding to FIG. 6 in another embodiment of the present invention.

FIG. 14 is a view corresponding to FIG. 7 in another embodiment of the present invention.

[Explanation of symbols]

16: Belt type continuously variable transmission 72, 74: Variable pulley 76: Transmission belt 86: Primary hydraulic actuator 88: Secondary hydraulic actuator 180: First pressure regulating valve 190: Spool valve 198: Second plunger, 199: Third plunger (plunger means) P _belt : tension control pressure (second line oil pressure) P _bc : engagement operating oil pressure, P _cl : clutch oil pressure (third line oil pressure)

Claims (1)

(57) [Claims] 1. A vehicle belt-type continuously variable transmission including a pair of primary hydraulic actuators and a secondary hydraulic actuator for respectively changing the effective diameters of a pair of variable pulleys around which a power transmission belt is wound. A second line hydraulic pressure for belt tension control regulated from the line hydraulic pressure and a hydraulic pressure of a type that generates a third line hydraulic pressure regulated according to the throttle valve opening to act on a hydraulic friction engagement device. A control device, a spool valve operated to adjust the first line oil pressure, a hydraulic pressure in the primary hydraulic actuator,
Plunger means for applying a thrust corresponding to the highest oil pressure of the second line oil pressure and the third line oil pressure to the spool valve element, wherein the first oil pressure is higher than the highest oil pressure by a predetermined pressure. A hydraulic control apparatus for a belt-type continuously variable transmission for a vehicle, comprising a first pressure regulating valve for generating a line hydraulic pressure.