JPH07332481A - Control device for automatic transmission - Google Patents

Abstract

PURPOSE:To form a control device in a compact state by a method wherein by applying the oil pressure of a second frictional engagement element, a plunger is brought into contact with a spool and a control valve interlocking with the spool is located in the oil pressure feed and discharge oil passage of a first frictional engagement element. CONSTITUTION:Since a spool 251 is governed in such a state that an external control signal pressure is exerted on a plunger 252, a control valve 25 controls the oil pressure of a first frictional engagement element B-3 by means of an external control signal pressure, the oil pressure of a second frictional engagement element B-2, and a feedback oil pressure from a first frictional engagement element. Further, during other gear shift, since the oil pressure of the second frictional engagement element B-2 is not fed to the plunger 252, the plunger 252 is separated away from the spool 251. The spool 251 controls the oil pressure of the first frictional engagement element B-3 by means of the an external control signal pressure and the feedback pressure of the first frictional engagement element B-3. Thus, since a force exerted on the control valve 25 during grasp switching gear shift is ensured by increasing a pressure receiving area, a device can be formed in a compact manners.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an automatic transmission, and more particularly to a control device for regrabbing a frictional engagement element in a speed change mechanism for shifting the speed.

[0002]

2. Description of the Related Art Conventionally, in an automatic transmission, depending on the gear train configuration, one of two frictional engagement elements (specifically, a brake or a clutch) and the other of the two frictional engagement elements (specifically, a brake or a clutch) are engaged when shifting between specific gears. There is a case where a so-called re-grip operation is performed in which release is performed at the same time. In such a case, a one-way clutch is arranged in parallel with each frictional engagement element, and their action optimizes the engagement / release timing to avoid a drop in output shaft torque due to tie-up and engine blowing due to underlap. However, the one-way clutch may be omitted in some cases to make the transmission mechanism compact. In this case, a dedicated valve for controlling the discharge of the hydraulic pressure from one of the friction engagement elements and the supply of the hydraulic pressure to the other should be provided in the hydraulic pressure supply / discharge oil passage for the friction engagement elements. I won't. As a control device having such a configuration, there is a technique disclosed in Japanese Patent Laid-Open No. 5-157168. In this example, shifting from the 2nd speed to the 3rd speed (hereinafter referred to as 2
→ It is abbreviated as 3 shift. The friction engagement element on the side of releasing at the time of other shifts (the brake B- in the embodiment)
3. Similarly, the configuration of the embodiment will be described in parentheses below), and a valve (2-3 timing valve) for controlling the hydraulic pressure is used as a valve (B- (3 control valve).

[0003]

By the way, the adoption of such a structure is not necessarily suitable for downsizing the control device in accordance with the demands for multi-stage automatic transmission, weight reduction, and improvement of mountability. . Therefore, it is convenient if both of the above valves can be integrated to perform both functions for compactness, but in such a case, the following problems occur. That is, the grip change gear (2 → 3
At the time of speed change), the hydraulic pressures of the engagement side friction engagement element (brake B-2) and the release side friction engagement element (brake B-3) are applied to the valve from the first direction, and While operating the valve spool by applying an external control signal pressure (SLU linear solenoid pressure) from the opposite second direction, controls the first friction engagement element (brake B-3) pressure. During other gear shifts, due to the relationship between the external control signal pressure and the hydraulic pressure of the first friction engagement element (brake B-3) only,
Since the oil pressure of the element is controlled, the external control signal pressure for bringing it into a completely engaged state is the second control during the re-grasping shift (2 → 3 shift) than during the other shifts. Must be increased by the hydraulic pressure of the friction engagement element (brake B-2). However, the hydraulic range in which the valve that outputs the external control signal pressure (linear solenoid valve SLU) can accurately output is naturally limited. Causes a decrease in hydraulic output accuracy. However, if an attempt is made to control the grip change gear shift within an output width range where accuracy can be maintained, the engagement of the first friction engagement element cannot be maintained.

In view of the above, the present invention solves the above-mentioned problems and makes it possible to satisfy the hydraulic pressure control condition of the first friction engagement element while maintaining high accuracy by means of a unified valve, and thereby, The main object is to provide a control device for an automatic transmission that can achieve compactness.

[0005]

In order to solve the above problems, the present invention comprises a first friction engagement element and a second friction engagement element, and supplies hydraulic pressure to both friction engagement elements. In an automatic transmission that shifts gears by gripping when discharging, the hydraulic pressure of the first friction engagement element is fed back to the first transmission.
And an external control signal oil pressure is applied in a second direction opposite thereto, and a spool that adjusts the oil pressure of the first friction engagement element according to the pressure and a spool that is coaxial with the spool. A second friction engagement element for engaging the first friction engagement element
The hydraulic pressure of the second friction engagement element is applied in the first direction at the time of shifting the grip to release the friction engagement element of, and the external control signal hydraulic pressure is applied to the second direction at least during the shift. And a control valve that operates in conjunction with the spool when the plunger comes into contact with the spool by the application of the hydraulic pressure of the second friction engagement element, and supplies the hydraulic pressure to the first friction engagement element. It is configured to be arranged in the discharge oil passage.

[0006]

According to the present invention having such a structure, with the structure described above, the hydraulic pressure of the second frictional engagement element is supplied to the plunger of the control valve during the grip change gear shift, and The plunger operates as a unit, whereby the spool operates to regulate the external control signal pressure applied to the plunger in addition to the external control signal pressure applied to the spool. And controlling the hydraulic pressure of the first friction engagement element by the relationship between the external control signal pressure applied to two locations, the hydraulic pressure of the second friction engagement element, and the feedback hydraulic pressure from the first friction engagement element. You can On the other hand, during other gear shifts, the hydraulic pressure of the second friction engagement element is not supplied to the plunger of the control valve, so that the plunger to which the external control signal pressure is applied is separated from the spool, and as a result, the spool. Operates according to the pressure relationship between the external control signal pressure applied to it and the feedback pressure of the first friction engagement element to control the hydraulic pressure of the first friction engagement element.

Therefore, according to the above-mentioned invention, the force opposed to the hydraulic pressure applied to the control valve from the frictional engagement element on the engagement side at the time of shifting the grip is not the external control signal pressure itself but the pressure of the pressure. Since it can be secured by increasing the area, it is not necessary to expand the external control signal pressure output width accompanying the integration of a valve, and while preventing a decrease in accuracy,
A compact controller can be achieved.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 10 show a first embodiment of the present invention. First, the schematic structure of the entire automatic transmission will be described. As shown in FIG. 2, the mechanical portion of the automatic transmission 10 in this example is a sub transmission mechanism D including a front-end type overdrive planetary gear unit and a simple connection 3 The main transmission mechanism M, which is a planetary gear train and has four forward gears and one reverse gear, is combined to form a fifth gear, and this mechanism is connected to a torque converter T with a lockup clutch L.

The subtransmission mechanism D is a one-way clutch F associated with the sun gear S0, the carrier C0 and the ring gear R0.
-0, a multi-plate clutch C-0 arranged in parallel therewith, and a multi-plate brake B-0 connected in series therewith. On the other hand, the main transmission mechanism M includes sun gears S1 to S3, carriers C1 to C3,
Three sets of simple-connected gear units P1 to P3, which are directly connected to the respective transmission elements including the ring gears R1 to R3, are provided, and the multiple disc clutch C- is associated with the transmission elements of the respective gear units.
1, C-2, band brake B-1, multi-plate brake B-
2 to B-4 and one-way clutches F-1 and F-2 are provided. In the figure, reference numeral SN1 indicates a C0 sensor for detecting the drum rotation of the clutch C-0, and SN2 indicates a C2 sensor for detecting the drum rotation of the clutch C-2. Further, although not shown, each clutch and brake is a piston, which engages and disengages friction materials of those clutches and brakes.
A hydraulic servo device composed of a cylinder mechanism is provided.

As shown in FIG. 4, in the automatic transmission 10, a hydraulic control device 20 for controlling the mechanical section, the torque converter and the lock-up clutch having the above-mentioned structure, and a hydraulic source for the hydraulic control apparatus, which is incorporated in the mechanical section, are not shown. An oil pump is provided. In the vehicle-mounted state, the automatic transmission 10 is connected to the engine E, and the hydraulic control device 20 of the automatic transmission 10 has the solenoid valves SL1 to SL incorporated therein.
4 and each linear solenoid valve SLN, SLT, STU and connected to the automatic shift control computer 30, the automatic shift control computer 30 includes various sensors 40 arranged at various parts of the vehicle including the engine E and the automatic transmission 10. It is connected to the engine control computer 50.

In this automatic transmission 10, the rotation of the engine E shown in FIG. 4 is transmitted to the input shaft N of the auxiliary transmission mechanism D via the torque converter T shown in FIG. Under the control of the hydraulic control device, the rotation of the input shaft N engages the clutch C-0 to directly connect the sub transmission mechanism D, engages the clutch C-1 of the main transmission mechanism M, and other When all the frictional engagement elements are released, the sun gear S3 of the gear unit P3 enters the sun gear S3 and the one-way clutch F-2 prevents the ring gear R3 from rotating in the reverse direction.
It is output as high speed rotation.

Next, the second speed rotation is achieved when the auxiliary transmission mechanism D is directly connected and the clutch C-1 and the brake B-3 are engaged, and at this time, the ring gear R2 of the gear unit P2 is entered. The input is the carrier C1 of the gear unit P1.
Is output to the carrier C2 of the gear unit P2 and the ring gear R1 of the gear unit P1 directly connected thereto as a reaction force element, and the output shaft U is rotated at the second speed.

Similarly, in the third speed rotation, the auxiliary transmission mechanism D is also used.
Directly engage the clutch C-1 and the brake B-2,
This is achieved when the other components are released, and at this time, the input that has entered the ring gear R2 of the gear unit P2 is the sun gear S2.
Is used as a reaction force element and is output to the carrier C2 to rotate the output shaft U at the third speed.

Further, the fourth speed rotation is also achieved when the auxiliary transmission mechanism D is directly connected and both the clutch C-1 and the clutch C-2 are engaged, and at this time, the rotation is input to the ring gear R2 and the sun gear S2. Therefore, the gear unit P2 is directly connected and the input rotation is output as it is. And the fifth
The high speed rotation is performed by releasing the clutch C-0 and fixing the sun gear S0 by engaging the brake B-0 to increase the speed of the sub speed change mechanism D while the main speed change mechanism M is in the fourth speed rotation state. Is achieved in. Further, in reverse, the auxiliary transmission mechanism D is put in the above state, and the clutch C-2 and the brake B-4 of the main transmission mechanism M are set.
Input by the sun gear S2 of the gear unit P2 at this time, and the carrier C of the gear units P2 and P3 having the ring gear R3 as a reaction force element.
It is output as a reverse rotation of C2 and C3.

The relationship between the engagement / release of each friction engagement element and one-way clutch in each of the above shift speeds is shown in FIG. 3 as an operation table. In the figure, the circles are the clutches, the brakes are engaged, the one-way clutches are locked, the ● symbols are engaged only during engine braking, and the dashed circles are
The mark represents engagement or disengagement, and the ⊚ mark represents engagement not involved in power transmission.

In the automatic transmission 10 having such a structure,
In the present invention, the first friction engagement element is the brake B-3,
The second friction engagement element is applied as the brake B-2, and as shown in FIG. 1, the hydraulic pressure of the hydraulic servo device that engages / disengages the friction materials of the brake B-3 and the brake B-2. The 1-2 part shift valve 21, 2-3 shift valve 22, 3-4
Shift valve 23, B-2 release valve 24, B-3 control valve 25, relay valve 26 and B-2 accumulator 2
7 are provided, which are solenoid valves SL1 to SL4 shown in FIG. 4 for switching each shift valve, a lock-up linear solenoid valve SLU, and a B-2 accumulator 2
7 and accumulator control linear solenoid valve SLN for controlling the back pressure thereof, linear solenoid valve SL
It is controlled by a linear solenoid valve SLT or the like that outputs a control signal according to the engine load to U.

Of these, the control valve 25 arranged in the oil supply / exhaust oil passage for the hydraulic pressure to the brake B-3 feeds back the hydraulic pressure of the brake B-3 and is applied in the first direction (upward in the drawing). Is applied with an external control signal oil pressure (signal pressure output from the linear solenoid valve SLU) P _SLU in the opposite second direction (downward in the drawing), and the spool 251 for adjusting the oil pressure of the brake B-3 in accordance with these pressures. And is arranged coaxially with the spool 251.
The hydraulic pressure of the brake B-2 is applied in the upward direction in the drawing during the grip-changing shift for engaging the brake B-2 and releasing the brake B-3, and the linear solenoid valve SLU signal pressure is applied in the downward direction in the drawing at least during the shifting. The plunger 252 comes into contact with the spool 251 by the application of the hydraulic pressure of the brake B-2, and the spool 25
It is configured to operate in conjunction with 1.

Then, the hydraulic pressure for adjusting the brake B-3 hydraulic pressure to the control valve 25 is supplied through the 1-2 shift valve 21 as a shift valve which is not switched during the grip change gear shift. In addition, the control valve 25
A relay valve 26 controlled by the hydraulic pressure from the brake B-2 is disposed between the brake valve B3 and the brake B-3.

Further, the connection relationship between each valve and the oil passage will be described in detail. The D range pressure oil passage 201 connected to a manual valve (not shown) branches via the 1-2 shift valve 21, and one oil passage 201a is Relay valve 26 via 2-3 shift valve 22
Connected to the brake B-3 oil passage 203 via the valve 26.
connected to b. The other branched oil passage 201b is
3-4 shift valve 23, B-2 release valve 24 and then B-
The third control valve 25 is connected to the import 254 and is connected to the relay valve 26 from the valve 25 via the oil passage 203a.

The other D range pressure oil passage 202 connected to the manual valve branches via the 2-3 shift valve 22, and one oil passage 202a is connected to the brake B-2 oil passage 204 via the orifice. . The oil passage 204 is connected to the oil passage 202a via the B-2 release valve 24 and the check valve, and is also connected to the accumulator 27 via the orifice. The other branched oil passage 202b is 3-
It is connected to the clutch C-2 via the 4-shift valve 23.

The 3-4 shift valve 23 is provided for both the oil passages 201.
Solenoid valve SL3 in addition to connecting and disconnecting b and 202b
In order to apply the signal pressure (P _{SL 3} ) to the spool end of the B-2 release valve 24, the solenoid valve signal pressure oil passage 205
B-2 release valve 24 through (shown by two-dot chain line in the figure)
It is connected to the.

The B-2 release valve 24 is a brake B-2.
Is provided to form a bypass circuit for accelerating the drainage of the hydraulic pressure of the accumulator 27 at the end of the release, and has a spring-loaded spool 241 and the signal pressure of the solenoid valve SL3 via the 3-4 shift valve 23 ( P
_{SL 3} ) is applied to the end of the spool 241 to connect and disconnect the bypass oil passage 201d to the brake B-2 oil passage 204, and to the import 254 of the B-3 control valve 25 of the D range pressure oil passage 201b. Communication and plunger 2
The oil passage 201 of the oil passage 201e branched from the other D range pressure oil passage 201a
Connect to and disconnect from b. Therefore, the two oil passages 201 are connected to the import 254 of the B-3 control valve 25.
b, there is a possible parallel supply of D-range pressure (P _D) over the 2-3 shift valve 22 and 3-4 shift valve 23 via the 1-2 shift valve 21 from 201e.

The B-3 control valve 25 opens and closes one of the two lands provided on the spool 251 by the feedback pressure applied to the end of the spool 251 via the feedback signal pressure import 256, and the drain port on the other side. By opening and closing EX, the hydraulic pressure of the oil passage 203a connected to the out port 255 is adjusted, and the plunger 252 arranged coaxially with the spool 251 has a differential piston shape and has a linear difference in the diameter difference portion. Solenoid signal pressure (P _SLU ) is applied to the end face of the brake B-2 pressure of the oil passage 204a connected to the oil passage 204 of the brake B-2 via the 2-3 shift valve 22 so that the spool 251 can come into contact with and separate from the spool 251. It has a wide stroke area. The B-3 control valve 25 is also provided with a plunger 253 for changing the spring load on the spool 251 on the side opposite to the plunger 252, and the end face of the plunger 253 is connected via the B-2 release valve 24. It is possible to apply and release the D range pressure (P _D ) of the oil passage 201b.

The relay valve 26 is a spring-loaded spool type switching valve. The brake B-2 pressure of the oil passage 204 is applied to the spring-loaded side spool end and the line pressure (P _L ) is applied to the other spool end. Are applied in opposition to switch communication between the brake B-3 oil passage 203b, the oil passage 201a, and the oil passage 203a.

The operation status of the circuit configured as described above will be described below mainly with reference to the flowchart of FIG. 5 and the time charts of FIGS. (1) 1 → 2 shift control operation If it is determined in step 1 that the 1 → 2 shift is performed in step 2, in step 3, the 1-2 shift valve 21 is switched before the solenoid valve SL3 is turned on. It is turned off and the B-2 release valve 24 is brought to the right half position shown in FIG.
Next, in step 4, the 1-2 shift valve 21 is switched to the second speed state, the manual valve (not shown), the oil passages 201, 1-
2 shift valve 21, oil passage 201b, 3-4 shift valve 23 and B-2 release valve 24 through the D range pressure (P _D )
The brake B-3 pressure is supplied via the -3 control valve 25 to the servo means via the relay valve 26 and the oil passage 203b, while the clutch C-0 pressure is drained. Thereafter, in accordance with step 5, the B-3 control valve 25 directly controls the brake B-3 pressure in the sections a, b and c shown in FIG. Specifically, during the piston stroke of the servo means (section a), the return spring force sets the hydraulic pressure level for fast fill. In the section b, the output (P _SLU ) of the linear solenoid valve SLU is increased at a predetermined increase rate to cause a rotation change. In the section c, the linear solenoid valve SLU is changed according to the target rotation change.
Feedback control. End of 1 → 2 shift (2nd
(Synchronization), the solenoid valve SL3 is turned on to release the solenoid valve signal pressure (P _{SL 3} ) and the B-2 release valve 24 is switched to the left half position in the figure in accordance with step 6.
B-3 to the plunger 253 of the control valve 25 B-2
While applying the D range pressure (P _D) over the release valve 24, 2-3 D range pressure via the B-2 release valve 24 is switched from a different route via shift valve 22 (P _D) B- The brake B-3 pressure is rapidly increased to the line pressure (P _L ) by continuing to supply the servo means through the control valve 25, and the shift is completed. As a result, the second speed (2nd)
In the steady state, the plunger 253 of the B-3 control valve 25 is pushed down by the line pressure (P _L ) and the spool 2
51 is locked at the lowest position in the figure, while B-2
The spool 241 of the release valve 24 is returned to the upper position in the figure by releasing the solenoid valve SL3 signal pressure (P _{SL 3} ).

(2) 2 → 1 shift control operation Simultaneously with the shift determination in step 7, the output of the linear solenoid valve SLU is set to 100% in accordance with step 8.
Prepare for drain control of brake B-3 pressure. Next, in step 9, the solenoid valve SL3 is switched from on to off to set the B-2 release valve 24 to the right half position in the drawing, and B-3
The lock of the control valve 25 is released, and thereafter, the drain of the brake B-3 pressure is directly controlled by the output of the linear solenoid valve SLU. 1st speed (1s
t) After the synchronization, in step 11, the 1-2 shift valve 21 is switched to the first speed state, and the supply of the brake B-3 pressure is cut off.
Finally, in step 12, the solenoid valve SL3 is switched from OFF to ON, the C-0 exhaust valve is switched, and the supply of the clutch C-0 pressure is started.

(3) 2 → 3 shift control operation The output of the linear solenoid valve SLU is set to 100% at the same time when the shift is determined in step 13, and the output value is set according to the input torque when the solenoid valve SL3 is switched from ON to OFF. . Next, the solenoid valve SL3 is switched from ON to OFF to bring the B-2 release valve 24 to the right half position shown in FIG. 1, and the line pressure application to the end of the plunger 253 is released via the B-2 release valve 24. Then, the lock of the B-3 control valve 25 is released. After that, 2-3 shift valve 22
Is switched to the third speed side, and the supply of the D range pressure (P _D ) to the servo means for the brake B-2 pressure is started via the valve. B-3
The control valve 25 adjusts the brake B-3 pressure to a required minimum pressure (section a) according to the increase of the brake B-2 pressure. The inertia phase is feedback-controlled (section b) by the back pressure control of the B-2 accumulator 27. To prevent simultaneous lock, the timer is controlled to turn on the solenoid valve SL3, and the B-2 release valve 24 brakes B-3.
The supply of pressure is stopped and the supply of clutch C-0 pressure is started. Further, when the accumulation of pressure in the B-2 accumulator 27 is completed, the relay valve 26 is switched, the brake B-3 oil passage is cut off, and the gear shift ends.

[0028] (4) third speed (3rd) state D range pressure (P _D) of the 1-2 shift valve 21,3-4 shift valve 23 and B-2 release valve plunger 2 via 24
It is applied to the 53rd end as well as to the plunger 252 end via the 2-3 shift valve 22.
All of them including the spool 251 are displaced upward by the pressure receiving area difference of 252, and the springs are compressed to lock the three members in the contact state.

(5) 3 → 2 shift control operation In step 19, the solenoid valve SL3 is switched from ON to OFF and the B-2 release valve 24 is moved to the right half shown in FIG. 1 prior to the switching of the 2-3 shift valve 22. Position, unlock the B-3 control valve 25, and brake B-
Start supplying 3 pressures. Next, in step 20, the 2-3 shift valve 22 is switched to the second speed state, and the small orifice drain of the brake B-2 pressure is started. Due to the fast fill of the brake B-3, the piston stroke is ended before the second speed (2nd) synchronization (section a). In step 21, the back pressure control of the B-2 accumulator 27 controls the rotation change (section b). When the vehicle speed is high, the brake B-3 pressure is kept at a low pressure and increased in synchronization. When the vehicle speed is low, the brake B-2 pressure is maintained, and synchronization is achieved by gradually increasing the brake B-3 pressure. Second speed (2nd)
After the synchronization, in step 22, the solenoid valve SL3 is switched from off to on and the B-2 release valve 24 is switched, the rapid drain of the brake B-2 and the rapid engagement of the brake B-3 are performed, and the shift is completed.

Here, the linear solenoid pressure (P _SLU ) pressure receiving area of the B-3 control valve 25 is set to 1 → 2, 2 → 1.
The reason why the shift speed is increased during the 2 → 3 shift compared to during the 3 → 2 shift will be described with reference to FIG. 11 (note that the B-3 control valve shown in this figure is slightly different from the above in the spring load method). The relationship between the spool 251 and the plunger 252 is substantially the same as described above, though it is different). As the pressure regulating function of the B-3 control valve 25,
During 1 → 2, 2 → 1 and 3 → 2 shifts, it is only necessary to adjust the brake B-3 hydraulic pressure within the hydraulic range of the linear solenoid pressure ( _PSLU ) to secure the torque capacity of the brake B-3. Therefore, the pressure receiving area of the end face of the plunger 252 is set to A
₁ , the pressure receiving area of the diameter difference portion is A ₂ , the pressure receiving area of the diameter difference portion of the spool 251 is A ₃ , the pressure receiving area of the land end surface is A ₄ , and the brake B-3 pressure (P _{B 3} ) is P _{B 3} = A ₄ × P _SLU / A ₃ (1) is satisfied. On the other hand, during the 2 → 3 shift, the brake B-2 is in a state in which the hydraulic pressure (P ₁ ) until the hydraulic pressure overcomes the return spring force (see FIG. 9) acts on the B-3 control valve 25. Since it is necessary to secure the torque capacity of the brake B-3 with -3 hydraulic pressure, the brake B-3 pressure (P _{B 3} ') at that time is P _{B 3} ' = (A ₄ '× P _SLU -A ₁ × P _{B 2} ) / A ₃ (2) However, the torque capacity of the brake B-3 must be secured by maintaining the relationship of A ₄ '= A ₄ + A ₂ . Further, the hydraulic pressure of the brake B-3 is temporarily dropped by switching the circuit at the time of the 2 → 3 shift (see FIG. 9).
Since there is a possibility of a drop (indicated by a dotted line), it is necessary to set the brake B-3 hydraulic pressure (P _{B 3} ) high in order to correct this. That is, P _{B 3} '> P _{B 3} (3) From the above formulas (1), (2), and (3), the pressure receiving area A ₄ of the linear solenoid pressure (P _{SL U} ) at the time of the 2 → 3 shift 'Is 1
→ 2, 2 → 1 and 3 → 2 It is necessary to make it larger than during shifting.

In summary, according to the control device of the above embodiment, the force opposing the hydraulic pressure applied to the control valve 25 from the brake B-2, which is the frictional engagement element on the engagement side, is applied to the control valve 25 during the grip change gear shift. The external control signal pressure (P _SLU ) itself can be secured by increasing the pressure receiving area of the pressure, rather than the external control signal pressure (P _SLU ) itself.
_SLU ) By eliminating the need to expand the output width, it is possible to achieve a compact control device while preventing a decrease in accuracy. In addition, the brake B-3 to the control valve 25
By supplying the hydraulic pressure for adjusting the hydraulic pressure of the (first frictional engagement element) through the 1-2 shift valve 21 that is not switched during the grip change gear shift, the gear change is performed during the grip change gear shift. It is possible to avoid a transient decrease in the hydraulic pressure of the brake B-3 that occurs due to the switching of the 2-3 shift valve 22 that is directly involved in the gear shift shock, thereby reducing shift shock. Further, by controlling the relay valve 26 by the hydraulic pressure from the brake B-2 that is the second friction engagement element,
Since the hydraulic pressure of the brake B-3, which is the first friction engagement element, can be discharged regardless of the operation of the control valve 25, even when the control valve 25 is stuck in the closed state, the hydraulic pressure of the brake B-3 is reduced. It can prevent entrapment.

Although the present invention has been described in detail based on the embodiments, the present invention is not limited to this, and various specific configurations can be modified within the scope of the matters described in the claims. For example, as a modified example of the method of applying the linear solenoid valve SLU pressure to the B-3 control valve 25, there are circuit configurations in FIGS. FIG. 12 is an example in which the valve shown in FIG. 11 is arranged in the circuit shown in FIG. With this configuration, the linear solenoid valve SLU pressure (P _SLU ) and the spring load act in parallel (in the adding direction) on the spool 251 in the above embodiment, so that a small linear solenoid valve SLU pressure (P _SLU ) is applied. Since it is necessary to regulate the pressure, which is disadvantageous in terms of pressure regulation accuracy and responsiveness, in this example, since it acts in series (direction of canceling each other), a higher linear solenoid valve SL
Pressure adjustment with U pressure (P _SLU ) is possible, which is advantageous in terms of pressure adjustment accuracy and responsiveness. Further, FIG. 13 shows that the linear solenoid valve SLU pressure (P
_SLU ) is applied through the B-2 release valve 24, and FIG. 14 is an example in which the same configuration is applied to the valve of FIG.

Finally, in the above embodiment, the brake B-3 is used.
B-2 release valves 24, B
-3 The control valve 25 and the relay valve 26 are arranged in that order. The order is such that the brake B-3 due to the intermediate failure of the B-3 control valve 25
Even if the pressure is closed, the drain can be guaranteed by the relay valve 26, and the B-2 release valve 24 or the B-3 control valve 25 is controlled by the solenoid valve SL3 during the N → D operation for starting the third speed. This is aimed at the advantage that the flow rate loss can be eliminated by cutting off the supply to the B-3 control valve 25. In addition, as described above, B-3
Since the relay valve 26 is provided in series between the control valve 25 and the brake B-3, the B-3 control valve can be secured while ensuring the drain between the B-3 control valve 25 and the brake B-3 at the time of failure. There is an advantage that the problem that the brake B-3 pressure is drained does not occur at the time of fail when 25 is in the supply state and the relay valve 26 is locked in the drain state.

[Brief description of drawings]

FIG. 1 is a partial circuit diagram of a hydraulic control device for an automatic transmission according to a first embodiment of the present invention.

FIG. 2 is a skeleton diagram showing a speed change mechanism portion of the automatic transmission.

FIG. 3 is an operation table of the automatic transmission.

FIG. 4 is a block diagram showing a system configuration of the automatic transmission.

FIG. 5 is a control flowchart of the automatic transmission control device during each shift.

FIG. 6 is a partial circuit diagram showing an oil passage connection state of the hydraulic control device during a 1 → 2 shift.

FIG. 7 is a time chart of the automatic transmission at the time of the 1 → 2 shift.

FIG. 8 is a time chart when the automatic transmission has a 2 → 1 shift.

FIG. 9 is a time chart of the automatic transmission at the time of the 2 → 3 shift.

FIG. 10 is a time chart of the automatic transmission at the time of 3 → 2 shift.

FIG. 11 is an enlarged cross-sectional view showing a modified example of the control valve of the hydraulic control device.

FIG. 12 is a partial circuit diagram of another embodiment of a hydraulic control device incorporating the control valve.

FIG. 13 is a partial circuit diagram of another embodiment in which the application path of the external signal pressure to the control valve is changed.

FIG. 14 is a partial circuit diagram of another embodiment in which the connection form of the relay valve is changed.

[Explanation of symbols]

 10 Automatic Transmission B-2 Brake (Second Friction Engaging Element) B-3 Brake (First Friction Engaging Element) 21 1-2 Shift Valve 25 B-3 Control Valve 26 Relay Valve 251 Spool 252 Plunger

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masahiro Hayabuchi, 10 Takane, Fujii-cho, Anjo-shi, Aichi Prefecture Aisin AW Co., Ltd. (72) Akira Fukatsu, 10 Takane, Fujii-cho, Anjo-shi, Aichi Prefecture・ AW Co., Ltd. (72) Inventor Masato Kaikawa 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Automobile Co., Ltd. (72) Inventor Kagenori Fukumura 1, Toyota Town, Aichi Prefecture Toyota Motor Co., Ltd. (72) Inventor Hidehiro Ohba 1 Toyota-cho, Toyota-cho, Aichi Prefecture Toyota Motor Co., Ltd. (72) Inventor Yasuo Hojo 1 Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd. (72) Inventor Hiromichi Kimura 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Atsushi Tabata Toyota City, Aichi Prefecture Data-cho address 1 Toyota Motor Co., Ltd. in

Claims (1)

[Claims] 1. An automatic transmission comprising a first friction engagement element and a second friction engagement element, wherein the automatic transmission is configured to change the grip by supplying and discharging hydraulic pressure to and from the friction engagement elements. Is applied to the first direction by feeding back the oil pressure of the friction engagement element of, and the external control signal oil pressure is applied to the second direction opposite thereto, and the external control signal oil pressure of the first friction engagement element is applied according to the pressure. A spool for adjusting the hydraulic pressure, and a second friction engagement element that is disposed coaxially with the spool and that engages with the second friction engagement element to release the first friction engagement element during a re-grip shift. An oil pressure of the element is applied in the first direction, and the external control signal oil pressure is applied in the second direction at least at the time of shifting, and the oil pressure of the second friction engagement element is applied. The plunger contacts the spool and A control device for an automatic transmission, wherein a control valve that operates in conjunction with a pool is arranged in a hydraulic pressure supply / discharge oil passage for a first friction engagement element.