JPH05346160A - Control device for automatic transmission - Google Patents

Abstract

PURPOSE:To improve the durability of a solenoid valve and restrain electric power consumption in an automatic transmission, which is provided with a specified friction element coupled by means of a plurality of shift steps of different transmitting torque and controls the coupling pressure to couple the specified friction element by means of the solenoid valve. CONSTITUTION:Against a direct coupled clutch 32 engaged with a second shift of large transmitting torque and a fourth shift of small transmitting torque, at the fourth shift, coupling pressure is supplied from a line 42 to a second oil pressure chamber 322 of small pressure receiving area through a fourth and fifth shift valves 64, 65, and the line pressure from the line 42 is supplied to a first oil pressure chamber 321 of large pressure receiving area as the coupling pressure by non-electrifying a second linear solenoid valve 103. During shifting 4-3, the coupling pressure is released from the first oil pressure chamber 32 of large pressure receiving are by electrifying the second linear solenoid valve 103.

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 mounted on an automobile, and more particularly to a control device for an automatic transmission having a specific friction element that is engaged at a plurality of shift stages having different transmission torques.

[0002]

2. Description of the Related Art In an automatic transmission in which a torque converter and a speed change mechanism are connected to each other and a power transmission path of the speed change mechanism is switched by selectively engaging a plurality of friction elements, the shift speed is automatically switched. In some cases, a predetermined friction element may be engaged at a plurality of shift speeds having different transmission torques.
There is a friction element on the auxiliary transmission side in an automatic transmission having a main transmission and an auxiliary transmission as disclosed in Japanese Patent No. 9745.

That is, in this type of automatic transmission, for example, the low speed stage of the main transmission is combined with the low speed stage or the high speed stage of the auxiliary transmission to form the first speed and the second speed, and then the middle speed of the main transmission. When the third speed and the fourth speed are configured by combining the low speed speed or the high speed speed of the auxiliary transmission with the speed, the friction elements that are engaged at the high speed speed in the auxiliary transmission are engaged at the second speed and the fourth speed, for example. It will be. In this case, when the friction element is engaged at the 2nd speed, a large input torque must be transmitted because the gear stage on the main transmission side is a low speed stage, whereas the engagement at the 4th speed is achieved. In this case, since the shift stage on the main transmission side is the medium speed stage, it suffices to transmit a relatively small input torque. Thus, the specific friction element on the sub transmission side is There may be cases where the transmission torque is engaged at a plurality of shift speeds that differ.

[0004]

By the way, as described above, when a specific friction element in the auxiliary transmission is engaged at a plurality of shift stages having different transmission torques, the friction element has a constant torque capacity. At gears with large transmission torque, the capacity is insufficient and torque transmission becomes uncertain.
It takes a long time to complete the gear shifting operation at the time of gear shifting, and if the torque capacity is increased to avoid this, the capacity becomes excessive at a gear stage where the transmission torque is small, and The shock at the time will be great.

On the other hand, in the hydraulic circuit for controlling the supply and discharge of the engagement pressure to and from the friction element, the engagement pressure supplied to the specific friction element that is engaged at a plurality of gear stages having different transmission torques is increased by the gear stage. Alternatively, it suffices to provide a fastening pressure switching means for switching to a low pressure and make the torque capacity variable according to the transmission torque at each shift stage, but in this case, the structure of the hydraulic circuit becomes complicated.

Therefore, in order to engage a specific friction element with an engaging force corresponding to the transmission torque required at each gear in a plurality of gears having different transmission torques, for example, two large and small hydraulic pressures having different pressure receiving areas are used. A chamber is provided so that the engagement pressure is supplied to the hydraulic chamber with a large pressure receiving area at the gear stage with a large transmission torque, and the engagement pressure is discharged from the hydraulic chamber with a large pressure receiving area at the gear stage with a small transmission torque and the pressure receiving area is large. It is possible to supply the fastening pressure to a small hydraulic chamber.

A solenoid valve such as a linear solenoid valve or a duty solenoid valve may be used as the solenoid valve for adjusting the fastening pressure supplied to the large and small hydraulic chambers having different pressure receiving areas. When the engagement pressure supplied to or discharged from one of the hydraulic chambers of the specific friction element is controlled and the engagement pressure is supplied to the other of the hydraulic chambers of the specific friction element, the solenoid valve is switched to switch the one of the one of the hydraulic chambers. It is possible to discharge the fastening pressure from the hydraulic chamber. In this case, normally, the solenoid valve is configured to be energized to control its operation so that the engagement pressure is discharged from one of the hydraulic chambers of the specific friction element. Therefore, in the gear stage where the engagement pressure is supplied to the other of the hydraulic chambers of the specific friction element, the solenoid valve is always energized, and the durability of the solenoid valve becomes a problem. , Power consumption will increase.

Therefore, the present invention is directed to an automatic transmission having a specific friction element which is engaged at a plurality of shift stages having different transmission torques, and the engagement pressure for engaging the specific friction element is controlled by a solenoid valve. An object of the present invention is to improve the durability of the solenoid valve and suppress the power consumption by appropriately controlling the energization state of the solenoid valve according to the engagement state of the specific friction element.

[0009]

In order to solve the above problems, the present invention is characterized in that it is configured as follows.

First, the invention according to claim 1 of the present application (hereinafter,
In a control device for an automatic transmission having a specific friction element that is engaged at a plurality of shift stages having different transmission torques, a hydraulic chamber to which an engagement pressure for engaging the specific friction element is supplied, A first hydraulic chamber having a large pressure receiving area to which the fastening pressure is supplied at a gear stage having a large transmission torque and a second hydraulic chamber having a small pressure receiving area to which the fastening pressure is supplied at a gear stage having a small transmission torque are provided. First, second
It has a solenoid valve that controls the fastening pressure supplied to and discharged from one of the hydraulic chambers, and as the solenoid valve, a solenoid valve that directly outputs the original pressure from the hydraulic source without adjusting the pressure when not energized is used.
It is characterized in that control means is provided for cutting off the energization to the solenoid valve after the shift speed is achieved by supplying the engagement pressure to the other of the first and second hydraulic chambers.

The invention according to claim 2 of the present application (hereinafter,
The second invention) refers to the solenoid valve in the first invention,
Of the first and second hydraulic chambers, the fastening pressure supplied to and discharged from the first hydraulic chamber is controlled, and the source pressure from the hydraulic source is directly output without adjusting the pressure when not energized. The means is configured to cut off the energization to the solenoid valve after the shift speed is achieved by supplying the engagement pressure to the second hydraulic chamber of the first and second hydraulic chambers.

The invention according to claim 3 of the present application (hereinafter,
A third invention) is characterized in that each of the first hydraulic chamber and the second hydraulic chamber in the first invention or the second invention is constituted by a large-diameter piston and a small-diameter piston.

Furthermore, in the invention according to claim 4 of the present application (hereinafter referred to as the fourth invention), the control means in the above-mentioned first invention is changed by the supply of the fastening pressure to the other of the first and second hydraulic chambers. At the time of shifting from the shift stage where the energization to the solenoid valve is cut off after the stage is reached and the engagement pressure is supplied to both of these hydraulic chambers to engage the specific friction element, to the shift stage where the specific friction element is released. The engaging pressure of one of the hydraulic chambers is discharged first, and then the engaging pressure of the other hydraulic chamber is discharged.

[0014]

According to the first aspect of the invention, the solenoid valve is de-energized after the shift stage is achieved by supplying the engagement pressure to the other of the first and second hydraulic chambers to which the engagement pressure for engaging the specific friction element is supplied. It will be in a state. That is, since the solenoid valve is energized only during the transient period of shifting to the shift stage in which the fastening pressure is supplied to the other hydraulic chamber, the durability of the solenoid valve is improved and the power consumption is reduced. Will be reduced.

According to the second aspect of the invention, as in the first aspect of the invention, the solenoid valve is de-energized after the shift speed is achieved by supplying the engagement pressure to the second hydraulic chamber of the first and second hydraulic chambers. The solenoid valve is brought into a state, whereby durability of the solenoid valve is improved and power consumption is reduced. In particular, according to the second aspect of the invention, the solenoid valve is provided at the gear shift stage in which the engagement pressure is supplied to the second hydraulic chamber having a small pressure receiving area, that is, the gear shift torque that is frequently used during normal traveling and has a small transmitted torque. Is brought into a non-energized state, the durability of the solenoid valve is further improved and the power consumption is further suppressed.

By the way, when the first hydraulic chamber and the second hydraulic chamber having different pressure receiving areas are formed as in the first and second inventions, both chambers are provided with an inner peripheral portion and an outer peripheral portion on the back surface of one piston. However, in this case, if it is attempted to secure a pressure receiving area that matches the required torque capacity for each of the first and second hydraulic chambers, the piston diameter will increase. On the other hand, according to the third aspect of the invention, the first and second hydraulic chambers having different pressure receiving areas are respectively formed by the two pistons having the large diameter and the small diameter. The diameter of the piston can be reduced as compared with the case where the piston is formed on the outer peripheral portion.

On the other hand, according to the first and second inventions described above, in the gear stage in which the engagement pressure is supplied to the other hydraulic chamber (the second hydraulic chamber in the second invention) of the first and second hydraulic chambers. , The solenoid valve is in a non-energized state, and the solenoid valve supplies the source pressure from the hydraulic source to one of the first and second hydraulic chambers (the first hydraulic chamber in the second invention). Therefore, when shifting to a shift stage in which a specific friction element is released from the shift stage in this state, the engagement pressure should originally be discharged from the other hydraulic chamber. It is necessary to discharge the fastening pressure from both. In this case, when the engagement pressure is discharged from both hydraulic chambers at the same time, the engagement force of a specific friction element sharply decreases, and this abrupt change of the engagement force causes an increase in shift shock. According to the fourth aspect of the invention, at the time of shifting from the shift stage in which the engagement pressure is supplied to both the first and second hydraulic chambers and the specific friction element is engaged to the shift stage in which the specific friction element is released, The control means discharges the engagement pressure of either one of the hydraulic chambers first, and then the engagement pressure of the other hydraulic chamber, thereby simultaneously engaging the hydraulic chambers. As in the case of discharging the pressure, a sharp decrease in the fastening force is suppressed, and an increase in shift shock is prevented.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, an automatic transmission 1 according to this embodiment has a torque converter 10, a main transmission 20 arranged on the same axis as the torque converter 10, and a main transmission 20 parallel to these axes. And an auxiliary transmission 30 arranged on the axis.

The torque converter 10 includes a pump 12 integrated with a case 11 connected to the engine output shaft 2,
A turbine 13 arranged to face the pump 12 and driven by hydraulic oil by the pump 12, and a turbine 13 arranged between the pump 12 and the turbine 13 and supported by a transmission case 3 via a one-way clutch 14. Stator 1
5, a converter output shaft 16 connected to the turbine 13, and a lockup clutch 17 that directly connects the output shaft 16 to the engine output shaft 2 via the case 11.

The torque converter 10 and the main transmission 2
An oil pump 4 driven by the engine output shaft 2 via the torque converter 10 is arranged between the oil pump 4 and the engine 0.

The main transmission 20 has a converter output shaft 1
6 has a front planetary gear mechanism 21 arranged on the torque converter side and a rear planetary gear mechanism 22 arranged on the counter torque converter side. The converter output shaft 16 is connected to the sun gear 21a of the front planetary gear mechanism 21 via the forward clutch 23 and the sun gear 2 of the rear planetary gear mechanism 22 via the direct coupling clutch 24.
The sun gear 21a of the front planetary gear mechanism 21 and the ring gear 22b of the rear planetary gear mechanism 22 are coupled to each other.

A first one-way clutch 25 and a low reverse brake 26 are arranged in parallel between the ring gear 21b of the front planetary gear mechanism 21 and the transmission case 3, and at the same time the rear planetary gear mechanism 22 is provided. A second one-way clutch 27 and a 3-4 brake 28 are arranged in series between the sun gear 22a and the transmission case 3, and a coast brake 29 for engine braking is arranged in parallel with them. Then, the pinion carriers 21c, 22c of the front planetary gear mechanism 21 and the rear planetary gear mechanism 22 are coupled, and these are connected to the main transmission 2
An intermediate gear 5 that transmits power from 0 to the auxiliary transmission 30 is connected.

With such a configuration, the main transmission 20
According to the above, the forward clutch 23, the direct coupling clutch 24,
By selectively engaging the 3-4 brake 28 and the low reverse brake 26, a forward low speed stage, a medium high speed stage, a high speed stage and a reverse stage can be obtained.

On the other hand, the sub transmission 30 has a single planetary gear mechanism 31, and the intermediate gear 6 which is always meshed with the intermediate gear 5 in the main transmission 20 is connected to the ring gear 31a of the planetary gear mechanism 31. And the ring gear 31
A direct coupling clutch 32 is arranged between a and the sun gear 31b, and a third one-way clutch 33 and a reduction brake 34 are arranged in parallel between the sun gear 31b and the transmission case 3. Then, the planetary gear mechanism 31
The output gear 7 is connected to the pinion carrier 31c of the left and right drive wheels (not shown) from the gear 7 through a differential device.
Power is transmitted to.

The sub-transmission 30 can shift the power input from the main transmission 20 via the intermediate gears 5 and 6 to two forward gears, a low-speed gear and a high-speed gear, and output it to the output gear 7. It is like this.

That is, when the direct coupling clutch 32 is released, the sun gear 31 of the planetary gear mechanism 31 is driven by the third one-way clutch 33 or the reduction brake 34.
By fixing b, the power from the intermediate gear 6 input to the ring gear 31a of the planetary gear mechanism 31 is decelerated and output from the pinion carrier 31c to the output gear 7, whereby a low speed stage is obtained. In this case, if the deceleration brake 34 is engaged, the auxiliary transmission 30
As a single unit, the engine brake will operate.

The direct coupling clutch 32 is engaged,
If the deceleration brake 34 is released, the ring gear 31a and the sun gear 31b of the planetary gear mechanism 31 are coupled to each other, whereby the power from the intermediate gear 6 is directly output from the pinion carrier 31c to the output gear 7.
As a result, a high speed stage (direct connection stage) can be obtained.

In this way, the main transmission 20 obtains three forward and one reverse gears, and the auxiliary transmission 3
By setting 0, two high and low shift speeds can be obtained with respect to the output of the main transmission 20, so that the automatic transmission as a whole can obtain 6 shift speeds for forward travel and main shifts for reverse travel. The reverse gear as a whole is obtained by combining the reverse gear of the machine 20 and the low gear of the auxiliary transmission 30 to which the deceleration brake 34 is engaged. And in this example,
As the forward shift speed, a predetermined five speeds (for the first speed to the fifth speed) out of the above six speeds are adopted.

Here, the operating states of the clutches and brakes in each of the five forward gears and one reverse gear are summarized in Table 1. In addition, in Table 1, (◯) indicates that the engagement is performed only in the range for engine braking.

[0031]

[Table 1] In this embodiment, as the engagement pistons of the direct coupling clutch 32 and the deceleration brake 34 in the auxiliary transmission 30,
A double structure piston as shown in FIG. 2 is adopted.

That is, the direct coupling clutch 32 has the intermediate gear 6
And the drum member 3 integrated with the shaft member 35 to which the hub gear 32a integrally formed with the ring gear 31a of the planetary gear mechanism 31 and the sun gear 31b of the planetary gear mechanism 31 are fixed.
2b, a plurality of friction plates 32 on the driving side and the driven side
c and 32d are alternately arranged and these friction plates 3
A large-diameter first piston 32e having a large pressure receiving area is arranged at the back of 2c, 32d, and a small-diameter second piston 32f having a small pressure receiving area is further arranged at the back thereof, and the return of both pistons 32e, 32f is performed. It is configured to include a spring 32g.

Then, the first hydraulic chamber 32 _{1 at} the back of the first piston 32e into which the fastening pressure is introduced by the oil passage 36 and the second hydraulic pressure at the back of the second piston 32f in which the fastening pressure is introduced through the oil passage 37. Chamber 32 ₂ is provided, and when the same fastening pressure is introduced into these hydraulic chambers 32 ₁ and 32 ₂ , the first
When introduced into the hydraulic chamber 32 ₁ , a larger fastening force can be obtained than when introduced into the second hydraulic chamber 32 ₂ .

In the deceleration brake 34, a plurality of friction plates 34a and 34b on the driving side and the driving side are alternately arranged between the drum member 32b of the direct coupling clutch 32 and the transmission case 3, and a return spring is provided. A piston 34d that fastens these friction plates 34a and 34b against 34c is provided, and at the back of the piston 34d, a first hydraulic chamber 34 ₁ on the inner peripheral side with a large pressure receiving area and an outer peripheral side with a small pressure receiving area are provided. The second hydraulic chamber 34 ₂ and the second hydraulic chamber 34 ₂ are concentrically provided. When the same fastening pressure is introduced into these hydraulic chambers 34 ₁ and 34 ₂ , the case where the fastening pressure is introduced into the first hydraulic chamber 34 ₁ is introduced into the second hydraulic chamber 34 ₂ . In this case, a larger fastening force can be obtained.

Next, a hydraulic circuit for forming a shift speed according to the operating condition or the driver's request by selectively engaging each clutch and brake according to Table 1 will be described.

As shown in FIG. 3, in the hydraulic circuit 40, first, a regulator valve 4 for adjusting the pressure of the working oil discharged from the oil pump 4 to a predetermined line pressure.
1, a line pressure adjusted by the regulator valve 41 is operated by a main line 42 by a driver, and a first to third reducing valves for generating various control source pressures. 44,
45, 46 and so on.

These reducing valves 44 to 46
Of these, the control source pressure reduced to a constant pressure by the first reducing valve 44 is supplied to the modulator valve 48 via the line 47. Then, the control pressure adjusted by the duty solenoid valve 49 is supplied to the control port 48a of the modulator valve 48, and the duty solenoid valve 4
A modulator pressure is generated from the control source pressure according to a duty ratio of 9 (ratio of ON time in one ON / OFF cycle), and this modulator pressure is also applied to a first pressure increase of the regulator valve 41 via a line 50. Port 4
1a, whereby the line pressure is increased according to the duty ratio. In this case, the duty ratio is set according to, for example, the throttle opening degree of the engine, so that the line pressure is adjusted to a value according to the throttle opening degree. The line 50 supplied to the first pressure increasing port 41 a of the first pressure increasing port 41 has a first accumulator 51 for suppressing the pulsation of hydraulic pressure caused by the periodic ON / OFF operation of the duty solenoid valve 49.
Is installed.

The manual valve 43 has D,
3, 2, 1 forward range, R (reverse) range, N
It is possible to set a (neutral) range and a P (parking) range. In the forward range, the main line 42 is connected to the forward line 52, and in the R range, it is connected to the backward line 53.

The advancing line 52 is guided to the advancing clutch 23 through the orifice 54 whose throttle amount is different between when the hydraulic oil is supplied and when the hydraulic oil is discharged.
In each of the forward ranges of 3, 2, and 1, the forward clutch 23 is always engaged. In this case, the forward line 52 is provided with a second accumulator 55 for reducing a shock when supplying the fastening pressure to the forward clutch 23, and the accumulator 55 is connected to the accumulator 55 from the main line 42 through the line 56. Back pressure is supplied.

The reverse line 53 is used for the auxiliary transmission 3
0, the deceleration brake 34 is directly guided to the first hydraulic chamber 34 ₁ having a large pressure receiving area, and therefore, in the R range, the line pressure introduced into the first hydraulic chamber 34 ₁ causes the deceleration brake 34 to be strongly engaged. It will be concluded by force. In addition, a line 57 leading from the backward line 53 to the second pressure increasing port 41b of the regulator valve 41.
Is branched and the adjustment value of the line pressure is increased in the R range.

On the other hand, from the main line 42, the forward line 52 and the reverse line 53, the first, second and third shift valves 61, 62, 6 for shifting in the main transmission 20 are provided.
3, and line pressures are supplied to the fourth and fifth shift valves 64 and 65 for shifting in the auxiliary transmission 30.

Each of the shift valves 61 to 65 is provided with control ports 61a to 65a at one end thereof, and the control source pressure line 66 led from the second reducing valve 45 is used for the main transmission. 1st-3rd shift valve 61
The control source pressure line 67 led from the third reducing valve 46 is connected to each of the control ports 61a to 63a of the first to sixth control ports 63a to 63a, and the fourth and fifth shift valves 64 and 65 for the auxiliary transmission.
Of the control ports 64a and 65a.

The control source pressure lines 66 and 67 are provided with first to fifth ON-OFF solenoid valves 71 to 75 corresponding to the first to fifth shift valves 61 to 65. These ON-OFF solenoid valves 71 to
When the valve 75 is turned on, the control ports 61a to 65a of the shift valves 61 to 65 are drained. Therefore, the spools of the shift valves 61 to 65 are
Corresponding ON-OFF solenoid valves 71-75 are O
When it is N, it is located on the left side in the drawing, and when it is OFF, it is located on the right side.

And, these solenoid valves 71 to
ON / OFF combination of 75, that is, each shift valve 61
Lines leading to the respective clutches and brakes are selectively communicated from the main line 42, the forward line 52 or the reverse line 53 depending on the combination of the spool positions of ~ 65, and thereby each line according to the point shown in Table 1 above. The clutch and brake are engaged, and the first to fifth speeds and the reverse speed are obtained. In that case, the engagement pressure supplied to each clutch and brake is controlled to an appropriate value as follows.

That is, for the direct coupling clutch 24, the coast brake 29, the low reverse brake 26 and the 3-4 brake 28 in the main transmission 20, the control valve 76 for reducing the line pressure to adjust to a predetermined engagement pressure, 77, 78, 79, of which control valves 77, 7 for coast brake, low reverse brake, and 3-4 brake are provided.
For 8, 79, control ports 77a, 78a, 79
The control pressure adjusted by the first linear solenoid valve 80 is supplied to a via a line 81, and the fastening pressure is controlled in accordance with the control pressure.

Further, in the control port 76a of the direct coupling clutch control valve 76, the fastening pressure itself supplied to the direct coupling clutch 24 by the line 82 is passed through a line 85 provided with a one-way orifice 83 and a third accumulator 84. It is supplied as a control pressure, and the rise of the fastening pressure is controlled by the operation of the accumulator 84.

The first linear solenoid valve 8 described above
0 indicates the line 4 from the first reducing valve 44.
The control source pressure supplied via 7 is adjusted according to the control signal from the controller (see FIG. 4), and the control pressure according to the gear stage and the operating state at that time is generated.

The direct control clutch control valve 76 and the ports 76b, 78b provided at one end of the low reverse brake control valve 78 have pressure regulating operation inhibiting lines 86 branched from the retreat line 53. Are connected to each other, line pressure is supplied to these ports 76b and 78b in the R range, and the spool is fixed at the position on the left side in the drawing, so that the control valves for the direct coupling clutch and the low reverse brake 76, The pressure adjusting operation of 78 is blocked. Furthermore, 3-4 brake control valve 79
When fastening pressure is supplied to the coast brake 29, the fastening pressure is supplied to the port 79b at one end of the control valve 79 through the line 87, so that the pressure adjusting operation of the control valve 79 is restricted. There is.

Also, the first linear solenoid valve 8
The control pressure generated by 0 is supplied to the control port 8 of the accumulator control valve 88 via the line 81.
8a is also supplied. The control valve 88 adjusts the line pressure supplied from the main line 42 through the line 89 according to the control pressure from the first linear solenoid valve 80, and is used for the third accumulator 84 and the fourth accumulator 90. Back pressure of the two accumulators 8 via line 91
4, 90 back pressure ports 84a, 90a are supplied.

On the other hand, for controlling the engagement pressure in the auxiliary transmission 30, the first pressure receiving area of the direct coupling clutch 32 is large.
It is supplied to the control valve 101 for the direct coupling clutch that adjusts the engagement pressure supplied to the hydraulic chamber 32 ₁ and the second hydraulic chamber 32 ₂ having a small pressure receiving area, and the second hydraulic chamber 34 ₂ having a small pressure receiving area of the reduction brake 34. A deceleration brake control valve 102 for adjusting the engagement pressure and a second linear solenoid valve 103 are provided. As described above, the line pressure is directly supplied from the manual valve 43 to the first hydraulic chamber 34 ₁ having a large pressure receiving area of the deceleration brake 34 from the manual valve 43 through the reverse line 53 in the R range.

The second linear solenoid valve 103
Is supplied from the main line 42 as a control source pressure, which is adjusted according to a control signal (control current) from the controller, and then from the line 104 and the fifth shift valve 65 to the line 105 or the line 106.
Is supplied to the control port 102a of the deceleration brake control valve 102 via the
The hydraulic pressure of the hydraulic chamber 32 ₁ is adjusted by communicating with the _first hydraulic chamber 32 ₁ and is supplied from the main line 42 when the control current is 0 as shown in FIG. The line pressure is directly output without adjusting (reducing) the line pressure, and the line pressure is reduced as the control current increases to output a predetermined output hydraulic pressure. The first linear solenoid valve 80 has the same structure.

The deceleration brake control valve 102 receives the control pressure generated by the second linear solenoid valve 103 as described above.
When supplied to a, the main line 42 to the line 107, the fourth shift valve 64, the line 108, the fifth line
The line pressure supplied via the shift valve 65 and the line 109 is adjusted according to the control pressure, and the line pressure is adjusted to the line 1
It is supplied to the second hydraulic chamber 34 ₂ of the deceleration brake 34 via 10.

On the other hand, for the direct coupling clutch control valve 101, the main line 42 to the line 107, the fourth line
Line pressure is supplied through the shift valve 64 and the line 111, and after adjusting this, the one-way orifice 1
12, the line 113 and the fifth shift valve 65 are selectively supplied to the first hydraulic chamber 32 ₁ or the second hydraulic chamber 32 ₂ of the direct coupling clutch 32 via the line 106 or the line 114.

At the control port 101a of the direct coupling clutch control valve 101, the fastening pressure itself supplied to the first hydraulic chamber 32 ₁ or the second hydraulic chamber 32 ₂ of the direct coupling clutch 32 is the one-way orifice 115.
And the line 11 provided with the fifth accumulator 116
It is supplied as a control pressure via 7.
Therefore, the fastening pressure rises through a constant shelf pressure state due to the operation of the fifth accumulator 116.
The back pressure port 116a of the accumulator 116
The back pressure is supplied from the main line 42 through the line 118.

In the hydraulic circuit 40 having the above structure, the first to fifth ON-OFF solenoid valves 71 to 7 are provided.
The combination pattern of ON and OFF of No. 5 is as shown in Table 2, and thereby the forward 1-5th speed and the reverse speed can be obtained. Here, in Table 2, (1),
(2) shows the first speed and the second speed in the engine braking range.

[0056]

[Table 2] Next, referring to Table 2, the relationship between the ON / OFF combinations of the ON-OFF solenoid valves 71 to 75 and the shift speed will be specifically described.

First, in the first speed in which the engine brake employed in the D range or the like does not operate, the first to third ON-OFF solenoid valves 71 to 73 on the main transmission 20 side are turned off.
In the N, OFF, and OFF states, the spools of the first to third shift valves 61 to 63 are located on the left side, the right side, and the right side, respectively. In this state, the line 121 branched from the forward line 52 communicates with the line 122 via the first shift valve 61, and further the second shift valve 62.
Through the line 123.
Is shut off by the third shift valve 63. Similarly, the other line 124 branched from the forward line 52 is blocked by the second shift valve 62, and the line 125 branched from the main line 42 is blocked by the first shift valve 61. Therefore, in this case, as described above, only the forward clutch 23, which is always engaged in the forward range, is engaged, and the low speed stage in which the engine brake does not operate in the main transmission 20 is obtained.

In the sub transmission 30, the fourth,
5th ON-OFF solenoid valves 74 and 75 are both O
In the FF state, the fourth and fifth shift valves 64, 6
Since the spools of No. 5 are both located on the right side, the main line 42 communicates with the line 108 via the line 107 and the fourth shift valve 64, and further the deceleration brake control valve 10 via the fifth shift valve 65.
The line pressure is supplied to the control valve 102 by communicating with the line 109 extending to 2. At this time, the control pressure generated by the second linear solenoid valve 103 is supplied to the control port 102a of the deceleration brake control valve 102 via the line 104, the fifth shift valve 65, and the line 105, so that the line pressure is increased. Is adjusted according to the control pressure to obtain a predetermined fastening pressure,
Second hydraulic chamber 3 of deceleration brake 34 via line 110
4 ₂ and the deceleration brake 34 is engaged.

Further, the direct coupling clutch 32 is provided in the first hydraulic chamber 3
2 ₁ line 106, the fifth shift valve 65, line 1
13, the direct coupling clutch control valve 101 and the line 111 to communicate with the drain port of the fourth shift valve 64, and the second hydraulic chamber 32 ₂ is connected to the line 114.
It is in a released state by communicating with the drain port of the fifth shift valve 65 via. As a result, the shift stage of the auxiliary transmission 30 becomes a low speed stage where the engine brake operates, and the automatic transmission as a whole becomes the first speed where the engine brake does not operate.

In the first speed in which the engine brake employed in the first range, the second range, etc. operates, the third solenoid valve 73 in the main transmission 20 is turned on in the first speed in which the engine brake is not operated. With this,
The spool of the third shift valve 63 is located on the left side. Therefore, in this case, the forward line 52 is the branch line 121, the first shift valve 61, the line 12
The line pressure is supplied to the control valve 78 by communicating with the line 126 leading to the low reverse brake control valve 78 via the second and second shift valves 62, the line 123, and the third shift valve 63.

The line pressure supplied to the control valve 78 is the first linear solenoid valve 80.
Is adjusted to a fastening pressure according to the control pressure supplied to the control port 78a via the line 81 from the line 1
It is supplied to the low reverse brake 29 via 27.
As a result, in addition to the forward clutch 23, the low reverse brake 29 is engaged, and the low speed stage in which the engine brake operates in the main transmission 20 is obtained.
Then, in the auxiliary transmission 30, the deceleration brake 34 is engaged as in the case of the above-described first speed in which the engine brake is not operated, so that the automatic transmission as a whole can obtain the first speed in which the engine brake is operated.

Next, in the engine brake non-operating second speed adopted in the D range and the like, and in the engine brake operating second speed adopted in the first range and the second range, etc., the engine brake non-operating first speed and Engine brake operation 1
Only the shift speed of the auxiliary transmission 30 changes with respect to the speed state.

That is, the fourth ON- in the auxiliary transmission 30.
The OFF solenoid valve 74 is turned ON, and accordingly, the spool of the fourth shift valve 64 is positioned on the left side.
Therefore, the line pressure supplied from the main line 42 to the fourth shift valve 64 via the line 107 is supplied from the fourth shift valve 64 to the direct coupling clutch control valve 101 via the line 111, and the control is performed. The rising of the valve 101 is adjusted, and then the first hydraulic chamber 32 of the direct coupling clutch 32 is passed through the line 113, the fifth shift valve 65, and the line 106.
_Will be supplied to ₁ . As a result, the auxiliary transmission 30
As a result, the gear shift stage becomes a high speed stage, and as a result, the automatic transmission as a whole can obtain the second speed in which the engine brake does not operate or the second speed in which the engine brake operates.

Further, in the third speed, in the main transmission 20,
The first to third ON-OFF solenoid valves 71 to 73 are turned OFF, ON, and ON, and accordingly, the spools of the first to third shift valves 61 to 63 are located on the right side, the left side, and the left side. In this case, first, the forward line 5
One branch line 121 from 2 connects to the line 128 via the first shift valve 61 and further to the line 129 connecting to the coast brake control valve 77 via the third shift valve 63. Therefore, the line pressure is supplied to the control valve 77,
This is the line 81 from the first linear solenoid valve 80.
Is adjusted to a predetermined fastening pressure in accordance with a control pressure supplied via the coast brake 2 via a line 130.
9, so that the coast brake 29 is fastened.

The other branch line 124 from the forward line 52 communicates with the line 131 leading to the 3-4 brake control valve 79 via the second shift valve 62 and supplies the line pressure to the control valve 79. .. A control pressure is supplied to the control valve 79 from the first linear solenoid valve 80 via a line 81, and a fastening pressure supplied to the coast brake 29 is supplied as a control pressure via a line 87. The engagement pressure adjusted according to these control pressures is supplied to the 3-4 brake 28 via the line 132.

As a result, in the main transmission 20, the 3-4 brake 28 is engaged in addition to the forward clutch 23,
In addition, by engaging the coast brake 29 as well, the medium speed stage in which the engine brake operates can be obtained.

On the other hand, in the auxiliary transmission 30, both the fourth and fifth ON-OFF solenoid valves 74 and 75 are OF.
In the state of F, as in the case of the above-described first speed, the shift speed is set to the low speed in which the engine brake operates. Therefore, as a whole of the automatic transmission, the third speed that has the predetermined reduction ratio and the engine brake is activated can be obtained.

In the 4th speed, the 4th and 5th ON-OFF solenoid valves 74 and 75 of the auxiliary transmission 30 are both turned ON from the state of the 3rd speed, and the 4th and 5th shift valves 64 and 65 are turned on. The spool is located on the left side, so that, as in the case of the above-described second speed, first, the line pressure is changed from the main line 42 through the line 107, the fourth shift valve 64, and the line 111 to the control valve 101 for the direct coupling clutch. Is supplied to the control valve 1
The start-up is adjusted at 01, and the predetermined tightening pressure is reached.
From the line 113 and the fifth shift valve 65, this time via the line 114, the second hydraulic chamber 32 of the direct coupling clutch 32.
₂ will be supplied. As a result, the direct coupling clutch 3
2 is engaged and the shift stage of the auxiliary transmission 30 becomes the high shift stage.
In this case, in the present embodiment, the direct coupling clutch 32
After the gear shift stage is achieved by supplying the fastening pressure to the second hydraulic chamber 32 ₂ , the second linear solenoid valve 103 is de-energized and the line pressure from the main line 42 passes through the linear solenoid valve 103. Is further supplied to the direct coupling clutch 3 via the fifth ON-OFF solenoid valve 65 and the line 106.
It is also supplied to the second first hydraulic chamber 32 ₁ . Then, since the main transmission 20 is set to the medium speed as in the case of the above-described third speed, the speed of the automatic transmission as a whole becomes the fourth speed.

Further, in the 5th speed, the first to third ON-OFF solenoid valves 71 to 7 in the main transmission 20.
3 is OFF, ON, OFF, and the spools of the first to third shift valves 61 to 63 are located on the right side, the left side, and the right side. Therefore, the line 125 branched from the main line 42 passes through the first shift valve 61 and the line 133.
And the line 134 communicating with the direct coupling clutch control valve 76 via the third shift valve 63, and thus the line pressure is supplied to the control valve 76. Then, the engagement pressure adjusted by the control valve 76 is supplied to the direct coupling clutch 24 through the line 82 to engage the clutch 24. As a result, in the main transmission 20, the forward clutch 23 and the direct coupling clutch 24 are engaged, and the shift speed becomes a high speed. When the direct coupling clutch 24 is engaged, the engagement pressure is supplied through a constant shelf pressure state by the action of the third accumulator 84.

On the other hand, the auxiliary transmission 30 has the fourth and fifth ON-OFF solenoid valves 7 as in the case of the above-described fourth speed.
Since both gears 4 and 75 are in the ON state and the gear stage is set to the high gear stage, as a result, the automatic transmission as a whole can obtain the fifth gear.

Further, at the reverse speed when the manual valve 43 is operated to the R range, the reverse line 53 is communicated with the main line 42 through the manual valve 43, and the first to third ON-OFF solenoid valves are connected. 71 to 73 are in the OFF, OFF, and OFF states, and the spools of the first to third shift valves 61 to 63 are all located on the right side.

Therefore, first, the line 125 branched from the main line 42, as in the case of the above-described fifth speed,
A line 134 communicating with the line 133 via the first shift valve 61 and further communicating with the direct coupling clutch control valve 76 via the third shift valve 63.
Therefore, the line pressure is supplied to the control valve 76. In this case, a line pressure is supplied to the port 76b at one end of the control valve 76 from the retreat line 53 through the line 86, and the spool of the control valve 76 is fixed to the left side in the drawing, The line pressure supplied from the line 134 is directly supplied to the direct coupling clutch 24 via the line 82 without being decompressed.
4 is fastened with a high fastening pressure.

In addition, the retreat line 53 has an orifice 135 in which the throttle amount differs depending on the supply direction and discharge direction of the hydraulic oil.
The low reverse brake control valve 78 communicates with the control valve 78 through the line 136 having the above, the third shift valve 63, and the above-mentioned line 126, and the control valve 78 is the same as in the case of the first speed of the engine braking operation.
Supply line pressure to. In this case, the port 78b at one end of the control valve 78 has the retreat line 53
The spool of the control valve 78 is fixed to the left side in the drawing by introducing the line pressure by the line 86 branched from the line. Therefore, the above line 12
The line pressure supplied by 6 is directly supplied to the low reverse brake 26 without being adjusted by the control valve 78.
6 will be fastened with a high fastening pressure.

As a result, in the main transmission 20, the direct coupling clutch 24 and the low reverse brake 26 are engaged, and the reverse gear is obtained. Then, in the auxiliary transmission 30, the fourth and fifth ON-OFF solenoid valves 74, 7 are provided.
Since both 5 are OFF, the gear stage is set to the low speed stage where the engine brake operates, and a reverse speed with a large reduction ratio can be obtained.

Incidentally, when the fastening pressure is supplied to the low reverse brake 26, the working oil is introduced from the line 136 to the fourth accumulator 90 through the line 137, so that the fastening pressure is kept at a predetermined level. It will gradually rise after passing the shelf pressure.

In addition to the above configuration, the hydraulic circuit 40 includes the lockup clutch 1 in the torque converter 10.
7, lock-up first and second shift valves 141 and 142, a lock-up control valve 143, a lock-up control ON-OFF solenoid valve 144, and a duty solenoid valve 145.
Is provided, and engagement control and release control of the lock-up clutch 17 and slip control for slipping the clutch 17 are performed.

Then, the duty solenoid valve 49 for adjusting the line pressure and the first to fifth ON-OFF solenoid valves 71 to 7 for shifting, which are provided in the hydraulic circuit 40, are provided.
5, first and second linear solenoid valves 80 and 103 for adjusting engagement pressure, ON-OFF solenoid valve 145 for lockup control, and duty solenoid valve 1
45 is controlled by a control signal from the controller 160, as shown in FIG. The controller 160 includes a signal from a sensor 161 for detecting a vehicle speed, a signal from a sensor 162 for detecting an engine throttle opening, and a sensor 163 for detecting a shift position (range) selected by the driver. Signals and the like are input, and each of the solenoid valves is controlled in accordance with the operating state indicated by these signals and the driver's request.

Further, the controller 160 includes a first rotation sensor 1 for detecting the number of rotations of the main transmission 20 on the input side.
64, a second rotation sensor 165 that detects the number of rotations of the output side of the main transmission 20 (the input side of the sub transmission 30), and a third rotation sensor 1 that detects the number of rotations of the output side of the sub transmission 30.
66 is connected. Then, the controller 16
0 indicates that each of the above-mentioned sensors is arranged to synchronize the shift operation on the main transmission 20 side and the shift operation on the auxiliary transmission 30 side in order to promptly complete the shift operation at the time of shifting and prevent a shift shock. The gear ratios of the main transmission 20 and the auxiliary transmission 30 are calculated based on the signals from 164-166, and the gear change operation of the auxiliary transmission 30 is feedback-controlled based on this.

The automatic transmission according to this embodiment has the above-described structure. However, in this automatic transmission, as is clear from the above description, the direct coupling clutch in the auxiliary transmission 30 at the time of 1-2 shift. 32 is engaged, and the direct coupling clutch 32 is released at the time of 2-3 shift, and 3-4
When shifting, the direct coupling clutch 32 is reengaged. The engagement and disengagement operation of the direct coupling clutch 32 will be described in more detail with reference to FIGS. 6 to 8.

First, as shown in FIG. 6, at the first speed, in the auxiliary transmission 30, the fourth and fifth ON-OFF solenoid valves 74 and 75 are both OFF, and the fourth and fifth shifts are performed. Since the spools of the valves 64 and 65 are located on the right side, the main line 42 to the line 10
A line pressure is supplied to the deceleration brake control valve 102 through the seventh, fourth shift valve 64, line 108, fifth shift valve 65 and line 109, and this control valve 102 controls the second linear solenoid valve 103. After being adjusted according to the pressure, the second hydraulic chamber 34 ₂ of the deceleration brake 34 is supplied via the line 110.
Is supplied to the deceleration brake 34, that is, the deceleration brake 34 is engaged, that is, in the low speed stage.

At this time, the first hydraulic chamber 32 ₁ of the direct coupling clutch 32 has the first hydraulic chamber 32 ₁ of the fourth shift valve 64 via the line 106, the fifth shift valve 65, the line 113, the direct coupling clutch control valve 101 and the line 111. The second hydraulic chamber 3 communicates with the drain port 64b.
2 ₂ communicates with the first drain port 65b of the fifth shift valve 65 via the line 114, and the direct coupling clutch 3
2 is in the released state.

When shifting from this state to the second speed, as shown in FIG.
The fifth ON-OFF solenoid valves 74 and 75 are turned on,
When turned off, the spool of the fourth shift valve 64 is located on the left side and the spool of the fifth shift valve 65 is located on the right side.

In this case, from the main line 42 to the line 1
The line pressure supplied to the fourth shift valve 64 via 07 is supplied from the fourth shift valve 64 to the direct coupling clutch control valve 101 via line 111, and further from the control valve 101. Direct connection clutch 3 via one-way orifice 112, line 113, fifth shift valve 65 and line 106
2 is supplied to the first hydraulic chamber 32 ₁ and the direct coupling clutch 32
Is concluded. In addition, at this time, the second hydraulic chamber 34 ₂ of the deceleration brake 34 includes the fourth shift valve 64 via the line 110, the deceleration brake control valve 102, the line 109, the fifth shift valve 65, and the line 108.
To the second drain port 64c of the deceleration brake 3
4 is released.

As a result, the shift stage of the auxiliary transmission 30 shifts to the high shift stage and the 1-2 shift is completed.
-When the engaging pressure is supplied to the first hydraulic chamber 32 ₁ of the direct coupling clutch 32 at the time of the -2 shift, its rising is controlled as follows.

That is, the line pressure supplied from the fourth shift valve 64 to the direct coupling clutch control valve 101 is the control port 101 of the control valve 101.
The hydraulic oil output from the control valve 101 itself passes through the one-way orifices 112 and 115 by the line 117 and the accumulator 116 is adjusted to the control port 101a. After being operated, it is supplied as a control pressure, so that the control pressure and the fastening pressure adjusted corresponding thereto gradually rise through the shelf pressure state.

On the other hand, at the time of shifting from the second speed state to the third speed, the 3-4 brake 28 is engaged in the main transmission 20 to shift up the shift stage from the low shift stage to the medium shift stage and at the same time. In the auxiliary transmission 30, as in the case of the above-described first speed, the direct coupling clutch 32 is released, the second linear solenoid valve 103 is energized, and the deceleration brake 34 is engaged to shift the speed from the high speed to the low speed. Will be downshifted to.

Further, at the time of the 3-4 shift, as shown in FIG. 8, the fourth and fifth ON-OFF in the auxiliary transmission 30.
The solenoid valves 74 and 75 are switched from the OFF state to the ON-ON state, so that the spools of the fourth and fifth shift valves 64 and 65 are both located on the left side. This point is different from the 1-2 shift in which the spool of the fifth shift valve 65 is located on the right side.

In the fourth speed state, the line pressure supplied from the main line 42 to the fourth shift valve 64 via the line 107 is the same as the line pressure from the fourth shift valve 64 to the line 1.
Control valve 101 for direct coupling clutch via 11
Similarly to the case of the above-described 1-2 shift, the rising is adjusted by the action of the accumulator 116 and the like, and then the valve is supplied to the fifth shift valve 65 via the one-way orifice 112 and the line 113. Then, this time, the spool is located on the left side of the fifth shift valve 65, so that it is supplied to the second hydraulic chamber 32 ₂ having a small pressure receiving area of the direct coupling clutch 32 via the line 114. Further, in the fourth speed state, the power supply to the second linear solenoid valve 103 is cut off,
Thereby, the line pressure from the main line 42 is also supplied to the first hydraulic chamber 32 ₁ having a large pressure receiving area of the direct coupling clutch 32 to engage the direct coupling clutch 32, and the second hydraulic chamber of the deceleration brake 34 is also provided. 34 ₂ is line 11
0, the deceleration brake control valve 102 and the line 109 communicate with the drain port 65c of the fifth shift valve 65, and the deceleration brake 34 is released.

Further, in the present embodiment, in addition to the combination pattern of ON and OFF of the fourth and fifth ON-OFF solenoid valves 74 and 75 at the time of the normal speed change operation as described above, the fourth speed is changed to the third speed. The intermediate control pattern is set in correspondence with the shift of.

In this intermediate control pattern, the fourth and fifth ON-OFF solenoid valves 74 and 75, which are in the ON-ON state at the fourth speed, are OFF-O corresponding to the third speed.
While switching to the FF state, the fourth ON-O
Only the FF solenoid valve 64 is switched to the OFF state, and the second linear solenoid valve 103, which is in the non-energized state at the fourth speed, is energized, and the first and second hydraulic chambers 32 of the direct coupling clutch 32 are in the fourth speed state. ₁ , 3
It controls the discharge of the fastening pressure supplied to both 2 and ₂ .

Next, the shift control operation at the time of the 4-3 shift by the controller 160, which is a characteristic part of the present embodiment, will be described with reference to the flowchart shown in FIG. The signals from the sensors 161 to 166 are read, and in step S2, it is determined whether or not a 4-3 shift command is being issued based on the above signals. If NO, that is, 4-
If it is determined that the 3-speed command is not being issued, step S3
Other shift control is executed by, and if YES,
That is, when it is determined that the 4-3 shift command is being executed, a backup timer for ending the 4-3 shift within a predetermined period is set in step S4. Next, in step S5, the gear ratio on the main transmission 20 side is calculated based on the signals from the first and second rotation sensors 164 and 165 to finish the 4-3 gear shift, or the backup timer sets the time. Determine whether it has been up,
Until step S5 is determined as YES, step S
At 6, the intermediate control is executed.

That is, as shown in FIG.
4ON-OFF solenoid valve 64 is in the 4th speed ON state
Turn off the 4th shift valve 64.
Instead, the second hydraulic chamber 32 of the direct coupling clutch 32₂From fastening pressure
The second linear solenoid valve.
Switch the lube 103 from the non-energized state of the 4th speed to the energized state
The control current to increase the solenoid valve 103
Drain port 103a and line 104 and line 10
Direct connection by controlling to communicate with 6
First hydraulic chamber 32 of clutch 32 ₁To release the fastening pressure from
It As a result, as shown in FIG.
After the shift start time Ts, first, the direct transmission in the auxiliary transmission 30 is changed.
Second hydraulic chamber 32 of clutch 32₂The fastening pressure is discharged from
The second linear solenoid valve with a slight delay.
103 is switched from non-energized state to energized state
Control current of the linear solenoid valve 103
The drain port 103a is gradually opened,
As shown by (Pa) in FIG. 11, the linear solenoid valve is
The output oil pressure of the valve 103 gradually decreases to 0,
As shown in (b), the first hydraulic chamber 3 of the direct coupling clutch 32.
Two₁The fastening pressure (line pressure) is discharged from.

When it is determined to be YES in step S5, that is, based on the gear ratio on the main transmission 20 side,
-3 If it is determined that the shift operation has ended, or if the backup timer times out, step S7
In the fourth ON-OFF solenoid valve 64
At the same time, the fifth shift valve 65 is set to the OFF state by matching the fifth ON-OFF solenoid valve 65 with the third speed state.
And the deceleration brake 34 of the auxiliary transmission 30.
In order to supply the engagement pressure adjusted to a predetermined pressure to the second hydraulic chamber 34 ₂ in the above, a predetermined control current is output to the second linear solenoid valve 103, and the shift control to the third speed is completed. Thereby, the second linear solenoid 1
The drain port 103a of No. 03 is closed, and as shown by (Pb) in FIG. 11, the output hydraulic pressure of the linear solenoid valve 103 gradually increases after the 4-3 shift end determination time Te, and this output hydraulic pressure is increased. Is supplied to the port 102a of the deceleration brake control valve 102, and as shown in FIG. 6C, the fastening pressure is supplied to the second hydraulic chamber 34 ₂ of the deceleration brake 34, and the deceleration brake 34 is supplied. Is engaged, and the shift to the third speed is completed.

As described above, according to this embodiment, the pressure receiving area of the first and second hydraulic chambers 32 ₁ and 32 ₂ to which the engagement pressure for engaging the direct coupling clutch 32 of the auxiliary transmission 30 is supplied is small. Since the second linear solenoid valve 103 is in the non-energized state after the shift speed is achieved by the supply of the engagement pressure to the second hydraulic chamber 32 ₂ , that is, in the fourth speed state, the durability of the linear solenoid 103 is improved. Will be improved and power consumption will be reduced. In particular, in the fourth speed, which is frequently used during normal running, the second linear solenoid valve 103 is de-energized, so that the durability of the linear solenoid valve 103 is further improved and the power consumption amount is increased. Can be further suppressed.

By the way, at the 1st speed and the 3rd speed at which the engagement pressure must be supplied to the second hydraulic chamber 34 ₂ in the deceleration brake 34 of the auxiliary transmission 30, the second linear solenoid valve 103 is energized for some reason. Even if a situation occurs in which the line is shut off, the line pressure from the main line 42 is transmitted through the linear solenoid 103 at the shift speed to the port 10 of the deceleration brake control valve 102.
2a, so that even if the second linear solenoid valve 103 is de-energized due to an unexpected situation in the first speed or the third speed, as shown by the dotted line (d) in FIG. line pressure through 2 the hydraulic chamber 34 ₂ second linear solenoid valve 103 is supposed to be supplied as the engagement pressure, as the engagement pressure in first speed or third speed to the second hydraulic chamber 34 ₂ is not supplied The defect will be resolved and the fail-safe function will be secured.

Further, in this embodiment, as shown in FIG. 2, the first and second hydraulic chambers 32 ₁ and 3 of the direct coupling clutch 32 are provided.
Since 2 ₂ is composed of a large-diameter first piston 32e and a small-diameter second piston 32f disposed on the back of the large-diameter first piston 32e, the large-diameter first hydraulic chamber 34 is provided on the back surface of one piston 34d. _The pistons 32e and 32f can be made compact without increasing the diameter as the piston 34d of the deceleration brake 34 in which the first hydraulic chamber 34 ₂ and the first hydraulic chamber 34 ₂ are concentrically provided.

Further, in the present embodiment, the direct coupling clutch 32 is engaged from the fourth speed in which the fastening pressure is supplied to both the _first and second hydraulic chambers 32 ₁ and 32 ₂ to engage the direct coupling clutch 32.
When shifting to the 1st or 3rd speed, the first hydraulic chamber 32 ₂ is released as shown in FIGS. 11 (a) and 11 (b).
The fastening pressure is discharged earlier, and then the first hydraulic chamber 32 ₁
The fastening pressure is discharged more, and as a result, it is possible to prevent the fastening force from being sharply reduced as in the case where the fastening pressure is simultaneously discharged from the hydraulic chambers 32 ₁ and 32 _2. It is possible to prevent the shift shock from increasing.

FIG. 12 shows another embodiment in which the engagement pressure is discharged from the _first and second hydraulic chambers 32 ₁ and 32 ₂ of the direct coupling clutch 32 during the intermediate control. After the 4-3 shift disclosure time Ts from the high speed state, first,
With the second linear solenoid valve 103 energized,
As shown in (Pa ') of FIG. 12, by decreasing the output hydraulic pressure of the linear solenoid valve 103, as shown in (b') of the same figure, the engagement pressure (line pressure) is increased from the first hydraulic chamber 32 _1. ) Is discharged. Then, after a slight delay, the fourth solenoid valve 74 is turned off and the fourth shift valve 64 is switched to discharge the engagement pressure from the second hydraulic chamber 32 _{2 as} shown in (a ′) of FIG. Then, after a 4-3 shift end determination time Te, a predetermined control current is output to the second linear solenoid valve 103,
As shown by (Pb ') in FIG. 12, the output pressure of the linear solenoid valve 103 is increased, the fifth solenoid valve is turned off, and the fifth shift valve 65 is switched. As shown, the fastening pressure is supplied to the second hydraulic chamber 34 ₂ of the deceleration brake 34.

Also in this case, the first and second fastening pressures for fastening the direct coupling clutch 32 of the auxiliary transmission 30 are supplied.
After the shift speed is achieved by supplying the engagement pressure to the second hydraulic chamber 32 _{2 having} a smaller pressure receiving area among the hydraulic chambers 32 ₁ and 32 ₂ , that is, in the fourth speed state, which is frequently used during normal traveling, the second linear solenoid is used. Since the valve 103 is de-energized, the durability of the linear solenoid 103 is improved and the power consumption is reduced, and at the same time the fastening pressure is applied to the second hydraulic chamber 34 ₂ of the deceleration brake 34. In the 1st speed and the 3rd speed which must be supplied, even if a situation occurs in which the power supply to the second linear solenoid valve 103 is cut off for some reason, the main line is transmitted via the linear solenoid 103 at the shift speed. The line pressure from 42 is supplied to the port 102a of the deceleration brake control valve 102, which causes an unexpected situation in the first speed or the third speed. The second linear solenoid valve than 1
Even when 03 is de-energized, as shown by the dotted line (d ′) in FIG. 12, the line pressure remains as the fastening pressure in the second hydraulic chamber 34 ₂ of the deceleration brake 34 via the second linear solenoid valve 103. As a result, the problem that the engagement pressure is not supplied to the second hydraulic chamber 34 ₂ in the first speed or the third speed is solved and the fail-safe function is ensured.

Then, the first and second hydraulic chambers 32 ₁ and 3
12 (a ′), (b ′) in FIG. 12 when shifting from the 4th speed where the direct coupling clutch 32 is engaged by supplying the engaging pressure to both 2 ₂ to the 1st or 3rd speed where the direct coupling clutch 32 is released.
As shown in FIG. 1, first, the fastening pressure is discharged before the first hydraulic chamber 32 ₁ , and then the fastening pressure is discharged from the second hydraulic chamber 32 ₂ , whereby both hydraulic chambers 32 ₁ , Three
It is possible to prevent a rapid decrease in the engaging force as in the case where the engaging pressure is discharged from 2 ₂ at the same time, and it is possible to prevent an increase in shift shock.

In this embodiment, the first hydraulic chamber 32 ₁ in the direct coupling clutch 32 on the side of the auxiliary transmission 30 as a specific friction element and the second hydraulic chamber 34 in the deceleration brake 34 as another friction element. _The case where the operation of the second linear solenoid valve 103 is controlled when the fastening pressure is supplied to and discharged from the second linear solenoid valve 103 has been described, but the same solenoid valve as the second linear solenoid valve 103 is used. As the specific friction element and the other friction element whose fastening pressure is controlled to be supplied or discharged,
It is not limited to the direct coupling clutch 32 and the deceleration brake 34.

[0102]

As described above, according to the first and second inventions, the other one of the first and second hydraulic chambers (the second invention in the second invention) to which the engagement pressure for engaging the specific friction element is supplied. Since the solenoid valve is brought into the non-energized state after the shift speed is achieved by supplying the engagement pressure to the hydraulic chamber), the durability of the solenoid valve is improved and the power consumption can be suppressed.

In particular, according to the second aspect of the present invention, in the gear stage where the engagement pressure is supplied to the second hydraulic chamber having a small pressure receiving area, that is, in the gear stage where the transmission torque is small, which is particularly frequently used during normal traveling, Since the solenoid valve is de-energized, the durability of the solenoid valve is further improved and the power consumption can be further suppressed.

By the way, when the first hydraulic chamber and the second hydraulic chamber having different pressure receiving areas are formed as in the first and second inventions, both chambers are provided with an inner peripheral portion and an outer peripheral portion on the back surface of one piston. However, in this case, if it is attempted to secure a pressure receiving area that matches the required torque capacity for each of the first and second hydraulic chambers, the piston diameter will increase. On the other hand, according to the third aspect of the invention, the first and second hydraulic chambers having different pressure receiving areas are respectively formed by the two pistons having the large diameter and the small diameter. The diameter of the piston can be reduced as compared with the case where the piston is formed on the outer peripheral portion.

Further, according to the fourth aspect of the invention, from the shift speed at which the engagement pressure is supplied to both the first and second hydraulic chambers and the specific friction element is engaged to the shift speed at which the specific friction element is released. At the time of gear shift, the control means discharges the engagement pressure of one of the hydraulic chambers first, and then the engagement pressure of the other hydraulic chamber is discharged.
As in the case of releasing the fastening pressure from both hydraulic chambers at the same time,
It is possible to prevent the fastening force from rapidly decreasing, and to prevent an increase in shift shock.

[Brief description of drawings]

FIG. 1 is a skeleton view of an automatic transmission according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a structure of an auxiliary transmission in the same automatic transmission.

FIG. 3 is a circuit diagram showing a hydraulic circuit of the same automatic transmission.

FIG. 4 is a graph showing the output characteristic of a second linear solenoid valve that adjusts the engagement pressure supplied to the friction element in the auxiliary transmission.

5 is a control system diagram for each solenoid valve in the hydraulic circuit of FIG.

FIG. 6 is a sub-transmission control part 1 in the hydraulic circuit.
FIG. 6 is a circuit diagram showing a state at high speed and three time variations.

FIG. 7 is a sub-transmission control part 1 of the hydraulic circuit.
-2 is a circuit diagram showing a state at the time of shifting.

FIG. 8 is a sub-transmission control part 3 of the hydraulic circuit.
-4 is a circuit diagram showing a state during a shift.

FIG. 9 is a flowchart showing a 4-3 shift control operation by the controller.

FIG. 10 is a circuit diagram showing a state during intermediate control during the 4-3 shift of the auxiliary transmission control portion.

FIG. 11 is an explanatory diagram showing a change state of the engagement pressure on the auxiliary transmission side at the time of the 4-3 shift.

FIG. 12 is an explanatory diagram showing a change state of the engagement pressure on the auxiliary transmission side at the time of the 4-3 shift according to another embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Automatic transmission 20 Main transmission 30 Sub transmission 32 Direct coupling clutch 32 ₁ 1st hydraulic chamber 32 ₂ 2nd hydraulic chamber 32e, 32f Piston 34 Decelerating brake 34 ₂ 2nd hydraulic chamber 40 Hydraulic circuit 64 4th shift valve 65th 5 shift valve 74 4th ON-OFF solenoid valve 75 5th ON-OFF solenoid valve 101 direct connection clutch control valve 102 deceleration brake control valve 103 second linear solenoid valve 160 controller

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Toshihisa Maruesue 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Mazda Motor Corporation

Claims (4)

[Claims] 1. A control device for an automatic transmission having a specific friction element that is engaged at a plurality of shift stages having different transmission torques, wherein the hydraulic chamber is supplied with an engagement pressure for engaging the specific friction element, A first hydraulic chamber having a large pressure receiving area to which the engagement pressure is supplied at a gear stage having a large transmission torque and a second hydraulic chamber having a small pressure receiving area to which the engaging pressure is supplied at a gear stage having a small transmission torque are provided. At the same time, an electromagnetic valve for controlling the engagement pressure supplied to or discharged from one of the first and second hydraulic chambers is provided, and as the electromagnetic valve, an electromagnetic valve that directly outputs the original pressure from the hydraulic source when the power is not supplied is regulated. The automatic shift is characterized by using a valve and provided with control means for cutting off the energization to the solenoid valve after the shift stage is achieved by supplying the engagement pressure to the other of the first and second hydraulic chambers. Machine control equipment. 2. A control device for an automatic transmission having a specific friction element that is engaged at a plurality of shift stages having different transmission torques, wherein the hydraulic chamber to which the engagement pressure for engaging the specific friction element is supplied, A first hydraulic chamber having a large pressure receiving area to which the engagement pressure is supplied at a gear stage having a large transmission torque and a second hydraulic chamber having a small pressure receiving area to which the engaging pressure is supplied at a gear stage having a small transmission torque are provided. At the same time, it has an electromagnetic valve that controls the engagement pressure supplied to and discharged from the first hydraulic chamber of the first and second hydraulic chambers, and does not regulate the original pressure from the hydraulic source when the solenoid valve is not energized. A control means is provided that uses a solenoid valve that directly outputs, and that shuts off energization to the solenoid valve after a shift speed is achieved by supplying a fastening pressure to a second hydraulic chamber of the first and second hydraulic chambers. Control of automatic transmission characterized by apparatus. 3. The automatic transmission according to claim 1, wherein the first hydraulic chamber and the second hydraulic chamber are respectively constituted by a large-diameter piston and a small-diameter piston. Control device. 4. A control device for an automatic transmission having a specific friction element that is engaged at a plurality of shift speeds having different transmission torques, wherein the hydraulic chamber is supplied with an engagement pressure for engaging the specific friction element, A first hydraulic chamber having a large pressure receiving area to which the engagement pressure is supplied at a gear stage having a large transmission torque and a second hydraulic chamber having a small pressure receiving area to which the engaging pressure is supplied at a gear stage having a small transmission torque are provided. At the same time, an electromagnetic valve for controlling the engagement pressure supplied to or discharged from one of the first and second hydraulic chambers is provided, and as the electromagnetic valve, an electromagnetic valve that directly outputs the original pressure from the hydraulic source when the power is not supplied is regulated. The valve is used, and the solenoid valve is de-energized after the gear stage is achieved by supplying the engaging pressure to the other of the first and second hydraulic chambers, and the engaging pressure is supplied to both of these hydraulic chambers. Is the gear stage where the specific friction element is engaged When the gear is shifted to the gear stage in which the specific friction element is released, a control unit that first discharges the engagement pressure in one of the hydraulic chambers and then discharges the engagement pressure from the other hydraulic chamber is provided. A control device for an automatic transmission, which is provided.