JP2977989B2 - Control device for automatic transmission - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission mounted on an automobile, and more particularly to a control device for an automatic transmission which controls a fastening pressure supplied to a friction element by using a pressure regulating valve.

[0002]

2. Description of the Related Art A torque converter and a speed change gear mechanism are connected to each other, and a power transmission path of the speed change gear mechanism is switched by selectively engaging a plurality of frictional elements, thereby automatically setting a shift speed in accordance with an operation state of the vehicle. An automatic transmission which is designed to selectively switch is provided with a hydraulic circuit for supplying a fastening pressure to the friction element.
Japanese Patent Application Publication No. 150055 discloses a hydraulic circuit of this type including a linear solenoid valve for controlling a fastening pressure supplied to each friction element.

In this system, a pressure regulating valve is provided in a circuit for supplying a fastening pressure to a friction element, and a control pressure supplied to the pressure regulating valve is generated by a linear solenoid valve. According to this, by outputting a control signal from the controller to the linear solenoid valve and generating the control pressure supplied to the pressure regulating valve,
It is possible to freely control the engagement pressure supplied to the friction element, for example, it is possible to satisfactorily perform the engagement operation or the release operation of the friction element at the time of shifting to reduce shift shock, and After shifting, the torque transmission capacity of the friction element is adjusted to the input torque to the friction element, thereby avoiding an increase in the drive loss of the oil pump due to an unnecessary increase in the torque transmission capacity. Can be transmitted reliably.

[0004]

[SUMMARY OF THE INVENTION Incidentally, in the pressure regulating means such as a linear A Sole <br/> maytansinoid valve, taken control source pressure (line pressure) to adjust the output pressure by reducing the pressure Therefore, if the control accuracy is improved by narrowing the pressure regulation range of the output pressure, there is a problem that the engagement pressure supplied to the friction element becomes insufficient at a gear that requires a large torque transmission capacity.

The present invention addresses the above-mentioned situation in an automatic transmission provided with a pressure adjusting means for adjusting a fastening pressure supplied to a friction element, and provides a large torque without deteriorating the control accuracy of the pressure adjusting means. It is an object to provide a sufficient fastening pressure even when a transmission capacity is required.

[0006]

That is, a control device for an automatic transmission according to the invention of claim 1 of the present application (hereinafter referred to as first invention) reduces a fastening pressure supplied to a friction element to a line pressure. In an automatic transmission provided with pressure adjusting means for adjusting pressure, a bypass means for bypassing the pressure adjusting means, and a drain port provided in the pressure adjusting means when the pressure adjusting means is bypassed by the bypass means. And an exhaust pressure limiting means for limiting the exhaust pressure.

The invention of claim 2 of the present application (hereinafter referred to as “second
In the control device for an automatic transmission according to the present invention, in the configuration of the first invention, the bypass means includes a bypass path for bypassing the pressure regulating means, and a bypass valve installed in the bypass path. The drain valve of the pressure adjusting means is connected to a bypass valve, and when the pressure adjusting means is bypassed by the valve, the communication between the drain port and the drain port provided in the valve is shut off. .

A control device for an automatic transmission according to a third aspect of the present invention (hereinafter referred to as a third aspect) selectively supplies the engagement pressure to the configuration of the first or second aspect. The present invention is characterized in that the invention is applied to a pressure regulating means connected to a fastening pressure supply path of two friction elements.

Further, the control device for an automatic transmission according to the invention of claim 4 of the present application (hereinafter referred to as a fourth invention) comprises a friction element which is fastened at a plurality of shift speeds with different torque transmission capacities, In an automatic transmission provided with a pressure adjusting means for adjusting a fastening pressure supplied to the element by reducing a line pressure, the pressure adjusting means is provided when the friction element is fastened at a gear with a large torque transmission capacity. And a line pressure supply means for supplying a line pressure to the drain port side.

[0010]

According to the above arrangement, in any of the first to third aspects of the present invention, when the pressure regulating means is bypassed, the exhaust pressure from the drain port of the pressure regulating means is restricted or prohibited. Therefore, it is possible to supply a high line pressure as a fastening pressure to the friction element via the bypass means.

According to the second aspect of the present invention, since the mechanism for restricting the exhaust pressure from the pressure regulating means is provided in the bypass valve (bypass means), an increase in the number of parts is avoided and the hydraulic circuit is simplified. Will be.

According to the third aspect of the present invention, the above-described configuration is employed for the pressure adjusting means for adjusting the engagement pressure of the two frictional elements that are selectively engaged. This will be further simplified.

On the other hand, according to the fourth aspect of the invention, a friction element to be engaged at a plurality of gears with different torque transmission capacities and a pressure adjustment for adjusting the engagement pressure supplied to the friction element by reducing the line pressure. In an automatic transmission provided with a means,
Since the line pressure supply means for supplying the line pressure to the drain port side of the pressure adjustment means is provided when the friction element is fastened at the gear stage having a large torque transmission capacity, the pressure adjustment means is also used in this case. As the exhaust pressure is prohibited, a high line pressure can be supplied to the friction element as the engagement pressure.

[0014]

Embodiments of the present invention will be described below.

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

The torque converter 10 includes a pump 12 integrated with a case 11 connected to the engine output shaft 2,
A turbine 13 disposed opposite to the pump 12 and driven by the pump 12 via hydraulic oil, and disposed between the pump 12 and the turbine 13 and supported by the transmission case 3 via a one-way clutch 14 Then, a stator 15 for increasing the torque, an output shaft (turbine shaft) 16 connected to the turbine 13, and a lock-up clutch 17 for directly connecting the output shaft 16 to the engine output shaft 2 via the case 11 are provided. It is composed of

An oil pump 4 driven by the engine output shaft 2 via the case 11 is disposed between the torque converter 10 and the main transmission 20.

The main transmission 20 comprises a front planetary gear mechanism 21 disposed on the torque converter output shaft 16 on the torque converter side and a rear planetary gear mechanism 22 disposed on the anti-torque converter side. Have.

The torque converter output shaft 16
Is connected to the front planetary gear mechanism 2 via the direct coupling clutch 23.
1 and a sun gear 22a of the rear planetary gear mechanism 22 via a forward clutch 24, and a ring gear 21b of the front planetary gear mechanism 21 and the rear planetary gear mechanism 22.
And the sun gear 22a. A first one-way clutch 25 and an intermediate brake 26 are arranged in series between the sun gear 21a of the front planetary gear mechanism 21 and the transmission case 3, and are provided in parallel with the first one-way clutch 25 and the intermediate brake 26 for engine braking. 27 and the ring gear 2 of the rear planetary gear mechanism 22.
A second one-way clutch 28 and a low reverse brake 29 are arranged in parallel between the transmission case 3 and the transmission case 3.

The pinion carriers 21c, 22c of the front planetary gear mechanism 21 and the rear planetary gear mechanism 22
And an intermediate gear 5 for transmitting power from the main transmission 20 to the auxiliary transmission 30 is connected thereto.

With this configuration, the main transmission 20
Thus, three forward speeds and one reverse speed are obtained.

That is, when only the forward clutch 24 is engaged, the power from the torque converter output shaft 16 is input to the sun gear 22a of the rear planetary gear mechanism 22, and the ring gear 22b is connected via the second one-way clutch 28. As a result, the rotation of the torque converter output shaft 16 is output from the pinion carrier 22c of the planetary gear mechanism 22 to the intermediate gear 5 at a reduced speed at a large reduction ratio, and the first speed of the main transmission 20 is reduced. can get.

Further, from the state of the first speed, the intermediate brake 2
When the clutch 6 is engaged, the sun gear 21a of the front planetary gear mechanism 21 is fixed via the first one-way clutch 25, so that the torque converter output shaft 16 is connected via the forward clutch 24 and the sun gear 22a of the rear planetary gear mechanism 22. The power input to the ring gear 21b of the front planetary gear mechanism 21 is generated by the front planetary gear mechanism 21 as described above.
The speed is reduced at a reduction ratio smaller than the speed reduction ratio, and is output from the pinion carrier 21c to the intermediate gear 5, whereby the second speed of the main transmission 20 is obtained.

Further, when the direct coupling clutch 23 is engaged in the above-described second speed state, the power from the torque converter output shaft 16 is supplied to the forward clutch 24 and the rear planetary gear mechanism 2.
Front planetary gear mechanism 21 via the second sun gear 22a
Is input to the sun gear 21a of the front planetary gear mechanism 21 via the direct coupling clutch 23 at the same time. Accordingly, the entire front planetary gear mechanism 21 rotates integrally, and the rotation equivalent to the rotation of the torque converter output shaft 16 is output from the pinion carrier 21c to the intermediate gear 5, so that the third speed of the main transmission 20 is obtained. Can be

When the forward clutch 24 is released and the direct coupling clutch 23 and the low reverse brake 29 are engaged, the power from the torque converter output shaft 16 is input to the sun gear 21a of the front planetary gear mechanism 21. On the other hand, when the ring gear 22b of the rear planetary gear mechanism 22 is fixed, the two planetary gear mechanisms 2
The rotation of the torque converter output shaft 16 is output from the first and second pinion carriers 21c and 22c to the intermediate gear 5 in a reverse direction, and a reverse speed is obtained.

At the time of deceleration in the first speed and the second speed, the second and first one-way clutches 28 and 25 run idle and the engine brake does not operate. At the first speed, the low reverse brake 29 in parallel with the second one-way clutch 28 is engaged.
Coast brake 27 parallel to one-way clutch 25
Is established, the first and second speeds at which the engine brake operates are obtained.

On the other hand, the auxiliary transmission 30 is a planetary gear mechanism 3
1 is connected to the ring gear 31a of the planetary gear mechanism 31 while the intermediate gear 6 always meshing with the intermediate gear 5 of the main transmission 20 is provided.
A direct coupling clutch 32 is disposed between the ring gear 31a and the sun gear 31b, and a third one-way clutch 33 and a reduction brake 34 are disposed in parallel between the sun gear 31b and the transmission case 3. . An output gear 7 is connected to a pinion carrier 31c of the planetary gear mechanism 31, and power is transmitted from the gear 7 to left and right drive wheels (not shown) via a differential device.

The auxiliary transmission 30 is capable of shifting the power input from the main transmission 20 via the intermediate gears 5 and 6 to two forward stages and outputting the power to the output gear 7.

That is, when the direct coupling clutch 32 is released and the deceleration brake 34 is engaged, the planetary gear mechanism 31
Is fixed, the power from the intermediate gear 6 input to the ring gear 31a of the planetary gear mechanism 31 is reduced and output from the pinion carrier 31c to the output gear 7, and the direct coupling clutch 32 When the gear is engaged and the deceleration brake 34 is released, the ring gear 31a and the sun gear 31b of the planetary gear mechanism 31 are connected, so that the power from the intermediate gear 6 is output to the output gear 7 as it is. Become.

In this manner, the main transmission 20 provides three forward speeds and one reverse speed, and the subtransmission 3
With 0, two forward speeds are obtained with respect to the output of the main transmission 20, so that the automatic transmission as a whole has six forward speeds and two reverse speeds. In the embodiment, among these shift speeds, five forward speeds and one reverse speed
The shift speed of the gear is adopted.

Table 1 summarizes the operating states of the clutches and brakes at each of the five forward speeds and one reverse speed. In Table 1, (○) indicates that the vehicle is engaged only at the gear position for engine braking.

[0032]

[Table 1] Next, a description will be given of a hydraulic circuit that selectively engages each clutch and brake in accordance with Table 1 to form a shift speed according to an operating state or a driver's request.

As shown in FIG. 2, the hydraulic circuit 40 includes a regulator valve 4 for adjusting the pressure of hydraulic oil discharged from the oil pump 4 to a predetermined line pressure.
The main line 42 controls a manual valve 43 operated by a driver, and first to third reducing valves for generating various control source pressures. 44,
45 and 46.

These reducing valves 44 to 46
The control source pressure reduced by the first reducing valve 44 is supplied to the modulator valve 48 via the line 47 and the
The control pressure adjusted by the duty solenoid valve 49 is supplied to the control port 48a of No. 8. Therefore, in the modulator valve 48, a modulator pressure is generated in accordance with the duty ratio of the duty solenoid valve 49 (the ratio of ON time during one ON / OFF cycle), and
When the modulator pressure is supplied to the first pressure increasing port 41a of the regulator valve 41 via the line 50, the line pressure is increased according to the duty ratio. In this case, by setting the duty ratio according to, for example, the throttle opening of the engine, the line pressure is adjusted to a value corresponding to the throttle opening. An accumulator 51 for suppressing the pulsation of the hydraulic pressure caused by the periodic ON / OFF operation of the duty solenoid valve 49 is provided in a line 50 for supplying the modulator pressure to the first pressure increasing port 41a of the regulator valve 41. Have been.

The manual valve 43 includes D,
3, 2, 1 forward range, R (reverse) range, N
A (neutral) range and a P (parking) range can be set. In the forward range, the main line 42 is connected to the forward 52 line, and in the R range, the main line 42 is connected to the reverse line 53. And forward line 5
2 is guided to the forward clutch 24 through an orifice 54 having a different throttle amount between the time of supply and discharge of the hydraulic oil. Therefore, in each forward range of D, 3, 2, and 1,
The forward clutch 24 is always engaged.

Here, a first accumulator 55 for reducing a shock at the time of supplying the engagement pressure to the forward clutch 24 is installed in the forward line 52, and the first accumulator 55 is connected to the accumulator 55 from the main line 42 through the line 5.
A back pressure is supplied via the line 6. Also,
A line 57 leading to the second pressure increasing port 41b of the regulator valve 41 is branched from the retreat line 53,
The adjustment value of the line pressure is increased in the 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, and 6 for shifting in the main transmission 20 are provided.
3 and the fourth and fifth shift valves 64 and 65 for shifting in the subtransmission 30 are supplied with line pressure.

Each of these shift valves 61 to 65 has a control port 61a to 65a at one end, and a control source pressure line 66 led from the second reducing valve 45 is connected to a second transmission line for the main transmission. 1st to 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 sub-transmission, and the fourth and fifth shift valves 64, 65 for the auxiliary transmission.
Are connected to the respective control ports 64a and 65a.

The control source pressure lines 66, 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, respectively. These ON-OFF solenoid valves 71 to 75 are used when the shift valves 61 to 65 are ON.
, And the spools of the respective shift valves 61 to 65 are connected to the corresponding ON-OFF solenoid valves 71a to 65a.
When ７５75 is ON, it is located on the left side of the drawing, and when ＯＦＦ75 is OFF, it is located on the right side.

Here, the relationship between the states of the first to fifth ON-OFF solenoid valves 71 to 75 and the gears is summarized in Table 2. In Table 2,
(1) and (2) show first and second speeds for engine braking. OFF ^* means that once turned ON,
Is switched to.

[0041]

[Table 2] Then, according to the combination of ON and OFF of each of the ON-OFF solenoid valves 71 to 75 as shown in Table 2,
By determining the positions of the spools of the shift valves 61 to 65, the main line 42 or the forward line 5 is determined.
The lines leading to the respective clutches and brakes are selectively communicated from the second or reverse line 53, whereby the respective clutches and brakes are engaged according to the conditions shown in Table 1 above, and the first to fifth speeds and the reverse speed are obtained. Will be.

In this case, for the direct coupling clutch 23, the coast brake 27, the low reverse brake 29 and the intermediate brake 26 in the main transmission 20, the control valve 76 for reducing the line pressure to adjust it to a predetermined engagement pressure, 77, 78, and 79 are provided, respectively. Among these valves, the control valves 77, 78, and 79 for the coast brake, the low reverse brake, and the intermediate brake are controlled by the control ports 77a, 78a, and 79a by the first linear solenoid valve 81. The pressure is supplied via a line 82, and the control port 76a of the direct-coupled clutch control valve 76 includes:
The engagement pressure itself supplied to the direct coupling clutch 23
Is supplied as a control pressure via the control valve.

The first linear solenoid valve 8
1 is a line 4 from the first reducing valve 44
The control source pressure supplied via the control line 7 and the line 84 is adjusted in accordance with a control signal from a controller (see FIG. 3) so as to generate a control pressure corresponding to a shift speed and an operating state at that time. Has become. A control valve 76 for the direct coupling clutch and a port 76 provided at one end of the control valve 78 for the low reverse brake are provided.
b, 78b are connected to pressure regulating operation inhibiting lines 86, 87 via a line 85 branched from the retreat line 53, respectively.
The line pressure is supplied to 78b, and the spool is fixed at the left position in the drawing, so that the control valves 76, 78 for the direct coupling clutch and the low reverse brake are provided.
The pressure adjustment (pressure reduction) operation is prevented. Further, when the fastening pressure is supplied to the coast brake 27, the fastening pressure is supplied to the port 79b at one end of the intermediate brake control valve 79 through the line 88, and the pressure regulating operation of the control valve 79 is performed. Is restricted.

The first linear solenoid valve 8
1 is also supplied to the control port 89a of the accumulator modulator valve 89. The modulator valve 89 adjusts the line pressure supplied from the main line 42 via the line 90 in accordance with the control pressure from the first linear solenoid valve 81 to form the second and third accumulators 91 and 9.
2 are generated, and this is applied to the back pressure ports 91 of these accumulators 91, 92 by lines 93, 94.
a, 92a.

Further, for controlling the auxiliary transmission 30,
A second linear solenoid valve 95 for adjusting the engagement pressure supplied to the direct coupling clutch 32 and the deceleration brake 34 is provided. This second linear solenoid valve 95 is
The line pressure is supplied from the main line 42 via a line 96 as a control source pressure, and is adjusted in accordance with a control signal from a controller to generate an engagement pressure supplied to the direct coupling clutch 32 or the deceleration brake 34. I do.

Here, the supply state of the engagement pressure to each clutch and brake at each shift speed by the hydraulic circuit 40 will be specifically described.

First, at 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 are set to O on the main transmission 20 side.
In the N, OFF, and OFF states, the spools of the first to third shift valves 61 to 63 are located on the left, right, and right sides, respectively. In this state, the line 101 branched from the forward line 52 communicates with the line 102 via the first shift valve 61, and further the second shift valve 62
Communicates with the line 103 via the
Is shut off by the third shift valve 63.

The other line 104 branched from the forward line 52 is cut off by the second shift valve 62, and the line 105 branched from the main line 42 is cut off by the first shift valve 61. Therefore, in this case, as described above, only the forward clutch 24 that is always engaged in the forward range is engaged, and the main transmission 20
In the first speed, the engine brake is not operated.

In the auxiliary transmission 30, the fourth,
The fifth ON-OFF solenoid valves 74 and 75 are both O
In the FF state, the fourth and fifth shift valves 64, 6
5 are located on the right side, the line 106 branched from the main line 42 communicates with the line 107 via the fourth shift valve 64, and
A line pressure is supplied to the brake 34 in communication with a line 108 communicating with the deceleration brake 34 via the shift valve 65. Accordingly, the deceleration brake 34 is engaged, and the speed of the subtransmission 30 is reduced, and as a result,
The gear position of the entire automatic transmission is the first speed at which the engine brake does not operate.

In the first speed for engine braking employed in the first range, the second range, and the like, the third solenoid valve 73 is turned off compared to the first speed in which the engine brake is not operated.
N, and accordingly, the spool of the third shift valve 63 is located on the left side.

Therefore, in this case, the forward line 52 is connected to the branch line 101 and the first shift valve 6.
1, line 102, second shift valve 62, line 10
The line pressure is supplied to the control valve 78 via the third and third shift valves 63 and communicates with a line 109 communicating with the low reverse brake control valve 78. And this control valve 78
Is adjusted to a fastening pressure corresponding to the control pressure supplied from the first linear solenoid valve 81, and the fastening pressure is supplied to the low reverse brake 29. As a result, in addition to the forward clutch 24, the low reverse brake 29 is engaged, and the main transmission 2
At 0, the first speed for engine braking is obtained. The gear stage of the auxiliary transmission 30 is set to the deceleration stage as in the case of the first speed in which the engine brake is not operated. Can be

Next, in the 2nd speed of the engine brake inoperative used in the D range and the like, and in the 2nd speed of the engine brake used in the 1 range and 2 range, etc., Only the shift speed of the auxiliary transmission 30 changes with respect to the first speed state for engine braking. That is, the fifth ON-OFF solenoid valve 75 of the subtransmission 30 is turned ON, and accordingly, the spool of the fifth shift valve 65 is located on the left side. Therefore, the line 107 leading from the fourth shift valve 64 to the fifth shift valve 65 is connected to the line 110 leading to the direct coupling clutch 32, and the direct coupling clutch 32 is engaged, so that the auxiliary transmission 30 Is the direct gear.
As a result, as a whole of the automatic transmission, the second speed in which the engine brake does not operate or the second speed in which the engine brake operates
Speed will be obtained.

When the sub transmission 30 is switched from the speed reduction stage to the direct connection stage, the fourth ON-OFF solenoid valve 74 is once turned on and then turned off. Therefore, the spool of the fourth shift valve 64 is temporarily located on the left side, and shuts off between the lines 106 and 107.
During this time, the second linear solenoid valve 95 adjusts the fastening pressure, and supplies this to the direct coupling clutch 32 via the line 97 and the fifth shift valve 65.

Further, at the third speed, the first to third ON-OFF solenoid valves 71 to 7
3 is OFF, ON, ON, and accordingly, the spools of the first to third shift valves 61 to 63 are shifted to the right, left,
It will be located on the left side. In this case, first, one branch line 101 from the forward line 52 communicates with the line 111 via the first shift valve 61, and further, a line 112 which communicates with the coast brake control valve 77 via the third shift valve 63. Communicate with Accordingly, the line pressure is supplied to the control valve 77, the line pressure is adjusted to the engagement pressure according to the control pressure from the first linear solenoid valve 81, and then supplied to the coast brake 27, and the brake 27 is engaged.

Further, the other branch line 104 from the forward line 52 communicates with a line 113 communicating with the intermediate brake control valve 79 via the second shift valve 62, and supplies a line pressure to the control valve 79. In this case, the control pressure from the first linear solenoid valve 81 is supplied to the control valve 79, and the engagement pressure supplied to the coast brake 27 is supplied as a control pressure via a line 88. Thus, the engagement pressure adjusted according to these control pressures is supplied to the intermediate brake 26. As a result, in the main transmission 20, the intermediate brake 26 is engaged in addition to the forward clutch 24, and the coast brake 27
Is also engaged, so that the second speed at which the engine brake operates is established.

On the other hand, in the auxiliary transmission 30, both the fourth and fifth ON-OFF solenoid valves 74 and 75 are turned off.
In the state of F, the shift speed is set to the deceleration speed as in the case of the first speed. Therefore, as a whole, the automatic transmission has a predetermined speed reduction ratio and can obtain the third speed at which the engine brake operates.

At the fourth speed, the first to third ON-OFF solenoid valves 71 to 7 are provided in the main transmission 20.
3 turns OFF, ON, and OFF, and the spools of the first to third shift valves 61 to 63 are located on the right, left, and right sides. Therefore, the line 105 branched from the main line 42 is connected to the line 114 via the first shift valve 61.
, And further communicates with the line 115 which communicates with the direct-coupled clutch control valve 76 via the third shift valve 63, so that 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 23 via the line 116, and the clutch 23 is engaged. Thereby, the main transmission 20
The third speed is established when the forward clutch 24 and the direct coupling clutch 23 are engaged. Here, when the direct coupling clutch 23 is engaged, the engagement pressure is gradually supplied by the action of the second accumulator 91.

On the other hand, the auxiliary transmission 30 is provided with the fourth and fifth ON-OFF solenoid valves 7 as in the case of the third speed.
Both the gears 4 and 75 are in the OFF state, and the gear stage is set to the reduction gear stage. As a result, the automatic transmission as a whole can obtain the fourth speed.

Then, from the state of the fourth speed, the auxiliary transmission 30
5th ON-OFF solenoid valve 75 is ON
As a result, the spool of the fifth shift valve 65 is located on the left side, so that the direct coupling clutch 32 of the subtransmission 30 is engaged, so that the gear stage becomes the direct coupling stage. As a result, the gear stage as the entire automatic transmission is shifted. 5th gear. Also in this case, when the sub-transmission 30 is switched to the directly connected stage, the fourth ON state is set.
When the -OFF solenoid valve 74 is once turned ON, the engagement pressure adjusted by the second linear solenoid valve 95 is temporarily supplied to the direct connection clutch 32.

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

Therefore, first, the line 105 branched from the main line 42 communicates with the line 114 via the first shift valve 61 in the same manner as in the case of the fourth and fifth speeds, and furthermore, the third line. The line 115 communicates with the direct-coupled clutch control valve 76 via the shift valve 63, so that line pressure is supplied to the control valve 76. in this case,
The line pressure is supplied from the retreat line 53 to the port 76b at one end of the control valve 76 via the lines 85 and 86, and the spool of the control valve 76 is fixed to the left side in the drawing. 1
The line pressure supplied from 15 is not reduced,
The direct coupling clutch 24 is supplied as it is via the line 116, and the direct coupling clutch 24 is engaged with a high engagement pressure.

The retreat line 53 has an orifice 117 having a different throttle amount in the supply and discharge directions of the hydraulic oil.
The low-reverse-brake control valve 78 is connected to the low-reverse-brake control valve 78 via the line 118 having the third shift valve 63 and the above-described line 109, and is connected to the control valve 78 in the same manner as in the case of the first speed for engine braking. Supply pressure. In this case, the control valve 7
Line pressure is introduced into the port 78b at one end of the line 8 by lines 85 and 87 branched from the retreat line 53, so that the spool of the control valve 78 is fixed to the left side in the drawing. Therefore, the line pressure supplied by the line 109 is supplied to the low reverse brake 29 without being adjusted by the control valve 78, and the low reverse brake 29 is engaged with a high engagement pressure.

As a result, in the main transmission 20, the direct coupling clutch 24 and the low reverse brake 29 are engaged, and a reverse speed is obtained. In this case, in the auxiliary transmission 30, the fourth and fifth ON-OFF solenoid valves 74,
Both 75 are in the OFF state and are in the state set to the reduction gear.

The low reverse bus brake 29
When the fastening pressure is supplied to the third accumulator 92 via the line 118 through the line 119, the fastening pressure gradually rises.

In addition to the above configuration, the hydraulic circuit 40 includes a lock-up clutch 1 in the torque converter 10.
7 is provided with lock-up first and second shift valves 121 and 122 for controlling the control valve 7, and a lock-up control valve 123.

The converter line 124 is led from the main line 42 to the first shift valve 121 and the control valve 123, and the control port 121a at one end of the first shift valve 121 is connected to the second reducing valve 121. A control line 66 from valve 45 is connected via line 125. And this line 1
25 is provided with an ON-OFF solenoid valve 126 for lock-up control, and when the valve 126 is OFF, the control port 121 of the first shift valve 121 is provided.
a, the spool of the valve 121 is located on the left side. At this time, the converter line 124 is connected to the torque converter 1.
Release line 1 leading to the lock-up release chamber 17a inside 0
27, whereby the lock-up clutch 17
Is released.

On the other hand, when the ON-OFF solenoid valve 126 is turned ON and the control pressure is drained from the control port 121a of the first shift valve 121,
When the spool of the valve 121 is positioned on the right side, the converter line 124 communicates with a fastening line 128 communicating with the lock-up fastening chamber 17b in the torque converter 10, whereby the lock-up clutch 17 is engaged. At this time, the release line 127 communicates with the lock-up control valve 123 through the first shift valve 121 and the line 129, and the operating pressure adjusted by the control valve 123 changes the lock-up clutch 17 as the lock-up release pressure. Is supplied to the release chamber 17b.

That is, the control line 123 from the first reducing valve 44 is connected to the control port 123a at one end of the control valve 123, and the duty solenoid valve 131 is installed on the control line 130. The control pressure supplied to the control port 123a is changed by the duty solenoid valve 13
The release pressure is adjusted by adjusting according to the duty ratio of the control signal given to 1.

The duty solenoid valve 1
The control pressure generated by 31 is also supplied to control port 122 a of second shift valve 122 via line 132. When the control pressure is equal to or less than a predetermined value,
Since the spool of the first shift valve 122 is located on the right side, the line 133 guided from the main line 42 via the line 56 communicates with the pressure regulation prevention port 123b of the control valve 123 via the line 134, When the line pressure is supplied to the port 123b, the operation of adjusting the release pressure by the control valve 123 is prevented. At this time, the lock-up clutch 17 is brought into a completely engaged state in which only the engagement pressure is supplied.

When the control pressure becomes equal to or higher than a predetermined value, the control valve 123 adjusts the release pressure, and the lock-up clutch 17 is slip-controlled in accordance with the release pressure. I have.

Here, the spool of the second shift valve 122 is located on the right side when the control pressure is not introduced, and at this time, the orifice 5 on the line 52 leading to the direct coupling clutch 24
4 is opened.

The hydraulic circuit 40 includes a duty solenoid valve 49 for adjusting line pressure, and first to fifth ON-OFF solenoid valves 71 to 7 for shifting.
5. First and second linear solenoid valves 81 and 95 for adjusting the fastening pressure, ON-OFF solenoid valve 126 for lock-up control, and duty solenoid valve 13
1 is controlled by a control signal from the controller 140 as shown in FIG. And
The controller 140 includes a sensor 1 for detecting a vehicle speed.
A signal from the sensor 41, a signal from the sensor 142 for detecting the throttle opening of the engine, a signal from the sensor 143 for detecting the shift position (range) selected by the driver, and the like are input and indicated by these signals. Each of the solenoid valves is controlled in accordance with an operating state or a driver's request.

By the way, the hydraulic circuit 40 as described above, the second re <br/> two A solenoid valve 95 for adjusting the engagement pressure supplied to the direct clutch 32 and a reduction brake 34 in the sub-transmission 30 Although are provided, the second linear a solenoid valve 95, as specifically shown in FIG. 4, the line pressure supplied from the main line 42 via a line 96 connected to the input port 95c , The amount of drain from the drain port 95b to the controller 140
The line pressure is reduced to a predetermined pressure by adjusting the pressure in accordance with a control signal from the controller and output to the output port 95c.

[0074] In this case, the second linear A solenoid valve 95
The output characteristics are described below. Initially, a predetermined maximum pressure that minimizes the amount of drainage is obtained when no current is supplied, and the amount of drainage is reduced in line with an increase in drive current. increased to a, there is a decreasing characteristic output pressure in linear a accordingly. That is, the output characteristics are such that the output pressure is inversely proportional to the drive current.

On the other hand, the first and second ports 65 selectively connected to the input port 65c by the movement of the spool 65b are connected to the fifth shift valve 65 which is shifted by turning on and off the fifth ON-OFF solenoid valve 75.
d, 65e are provided. And, the first port 65d communicating with the deceleration brake 34 via the line 108 is
The second port 65e communicating with the direct coupling clutch 32 via the line 110 is connected to the input port 65c when the spool 65b is located on the left side in the OFF state where the spool 65b is located on the right side. It is configured to be in communication. The fifth ON-OFF solenoid valve 75 has a first exhaust port 65f for exhausting the engagement pressure of the deceleration brake 34 and a second exhaust port 65g for exhausting the engagement pressure of the direct coupling clutch 32. The second exhaust pressure port 65g communicates with a line 110 communicating with the direct coupling clutch 32 in the OFF state, and the first exhaust pressure port 65f communicates with a line 10 communicating with the deceleration brake 34 in the OFF state.
8.

The fourth shift valve 64 has a fourth ON state.
ON the -OFF solenoid valve 74 includes a spool 64b to a shift operation by OFF, via a line 106 to an input port 64c of the line pressure to bypass the second linear A solenoid valve 95 is supplied, the input port 64c in the OFF state where the spool 64b is located on the right side, is adapted to be communicated with the output port 64d to the line 107 which joins the said second linear a solenoid valve 95 of the line 97 is connected.
That is, in the OFF state of the fourth shift valve 64 in which the spool 64b is positioned on the right side, so that the line pressure to bypass the second linear A solenoid <br/> Dobarubu 95 is supplied to the fifth shift valve 65.

In this embodiment, the fifth
A first exhaust line 136 for exhausting the fastening pressure via the first exhaust port 65f of the shift valve 65, and a second exhaust line 137 for exhausting the engaging pressure via the second exhaust port 65g. Are connected to the fourth shift valve 64. Of these, the first exhaust pressure line 136 is configured to selectively communicate with a first drain port 64d having a larger throttle amount and a second drain port 64f having a smaller throttle amount. I have. Specifically, when the spool 64b is in the OFF position, the first exhaust pressure line 1
36 communicates with the second drain port 64f having a small throttle amount. In addition, the other second exhaust pressure line 13
7 is the third drain port 64g with a large throttle setting
And a fourth drain port 64h having a smaller throttle amount than that. Also in this case, the second exhaust pressure line 137 communicates with the fourth drain port 64h having a small throttle amount at the OFF position of the spool 64b.

According to the above configuration, when the engagement pressure is supplied to the deceleration brake 34 via the line 108, the engagement pressure of the direct coupling clutch 32 is increased by the line 110, the fifth shift valve 65, the second exhaust pressure line 137, It will be released via the fourth shift valve 64. At that time, as shown in the figure, when the fourth shift valve 64 is in the OFF state,
It is released via the fourth drain port 64h having a small throttle amount. This means that for deceleration brake 34, the line pressure bypassing the second linear A <br/> solenoid valve 95, line 107, the downstream portion of the line 97, the fourth shift valve 64
This is because the pressure is supplied as the engagement pressure via the line 108, so that the pressure release speed of the other directly-coupled clutch 32 is increased and the quick release operation is performed.

[0079] In addition to the above configuration, the cut-off port 6 In this example, leading to the drain port 96b of the second linear A solenoid valve 95 via line 138
4i is provided in the fourth shift valve 64, and the cutoff port 64i is cut off from the communication with the fifth drain port 64j when the spool 64b is in the OFF position.

When both the fourth and fifth ON-OFF solenoid valves 74 and 75 are turned on, as shown in FIG. 5, the spool 64b of the fourth shift valve 64
In the drawing, the fifth shift valve 65
Is also located on the left side in the drawing. At this time, the line 107 connected to the output port 64d of the fourth shift valve 64 is closed, and the second linear valve 64 is closed.
The engagement pressure regulated by the solenoid valve 95 is supplied to the direct coupling clutch 32 via the line 97, the fifth shift valve 65, and the line 110. In this case, the engagement pressure of the deceleration brake 34 is
6, the pressure is discharged from the first drain port 64e of the fourth shift valve 64, which has a large throttle amount.

[0081] Then, in this embodiment, as shown in FIG. 5, in the non-bypassed state where the spool 64b of the fourth shift valve 64 is positioned on the left side, of the second linear A Seo <br/> Renoidobarubu 95 Drain Line 13 at port 95b
Is connected cutoff port 64i through 8 is communicated with the fifth drain port 64j, thereby the second linear A Seo <br/> Renoidobarubu 95 by pressure regulating operation is carried out.

[0082] On the other hand, as shown in FIG. 4, in the bypass when the spool 64b of the fourth shift valve 64 is positioned on the right side, connected via a line 138 to the drain port 95b of the second linear A solenoid valve 95 cutoff port 64i and communication with the fifth drain port 64j is blocked, whereby the second linear a solenoid according regulating pressure operation valve 95 is to be prohibited.

Next, a second embodiment of the present invention will be described with reference to FIG. 6. A shift valve 201 to which a line pressure is supplied via a main line 201 is turned on and off.
A control port 202a to which a control pressure adjusted by a solenoid valve 203 is supplied is provided.
N-OFF ON of the solenoid valve 203, the OFF, the line 2 leading to the input port 205a of the line 204 and linear A solenoid <br/> Dobarubu 205 leading to the friction element
06 is selectively communicated with the main line 201. Then, the shift valve 202 with the output port 205b of the Li <br/> two A solenoid valve 205 is connected via a line 207, the line 207 is merged into the line 204 leading to the friction element line against 208, and is configured to be communicated when the main line 201 is communicated with the line 206 to the linear a <br/> solenoid valve side.

Therefore, when the spool 202b of the shift valve 202 is located on the right side as shown in FIG.
4 to the friction element.

On the other hand, from this state, the spool 202b
When There moved leftward, with the line 206 is communicated with the main line 201, a line 207 connected to the output port 205b of the linear A solenoid valve 205, the line 208 communicated Tsu leading to friction element Will be done. Thereby, the pressure pressure regulated by the linear A solenoid valve 205 is supplied to the friction element as a fastening pressure. Note that reference numeral 209 denotes the above O
This is a reducing valve for generating a control source pressure for the N-OFF solenoid valve 203.

Next, a third embodiment of the present invention will be described with reference to FIG.

[0087] That is, in this third embodiment, the linear A solenoid valve 213 is interposed between the line 212 leading to the friction elements and line 211 which is branched from the main line 210, the linear A solenoid An ON-OFF solenoid valve 21 is provided between a line 214 branched from the line 211 on the upstream side of the valve 213 and a line 215 joining the line 212.
Control port 2 to which the control pressure adjusted by 6 is supplied
A shift valve 217 having an opening 17a is provided.

[0088] Then, the drain port 213a of the linear A <br/> solenoid valve 213 in this embodiment, retraction line 2 connected to the manual valve 218
19 are connected.

Therefore, R for which a high fastening pressure is required
In range, the line pressure via a retraction line 219 is applied to the drain port 213a of the linear A solenoid valve 213, thereby the drain port 21
The exhaust pressure from 3a is limited, and the line pressure is supplied as a high fastening pressure to the friction element via the main line 210, the line 211, the line 214, the shift valve 217, and the line 215. Reference numeral 220 denotes a reducing valve for generating a control source pressure for the ON-OFF solenoid valve 216.

[0090] The fourth embodiment shown in FIG. 8, manual in FIG valve 218 and linear A solenoid valve 213
A valve 221 for introducing a line pressure generated in the R range as pilot pressure is provided on a retreat line 219 interposed between the spool 221a and the spool 221a when the line pressure is high. It supposed to be located on the right side as to prohibit the exhaust pressure from the drain port 213a of the linear a solenoid valve 213.

[0091] On the other hand, linear A solenoid valve 2 when a low line pressure the spool 221a is moved to the left
13 drain port 213a to drain port 221b
While the hydraulic oil will be discharged through the fifth embodiment shown in FIG. 9, the upper retraction line 219 which is interposed between the manual valve 218 in FIG. 7 and <br/> linear A solenoid valve 213 in, which was set up accumulator 222 the line pressure generated in the R-range is introduced as a back pressure, a drain port 2 in <br/> linear a solenoid valve 213 when also the line pressure high in this case
The discharge operation from 13a is prohibited.

[0092]

As described above, according to the present invention, when the pressure regulating means is bypassed, the exhaust pressure from the drain port of the pressure regulating means is restricted or prohibited. It is possible to supply a high line pressure as a fastening pressure to the friction element.

According to the second aspect of the present invention, since the mechanism for restricting the exhaust pressure from the pressure regulating means is provided in the bypass valve (bypass means), an increase in the number of parts is avoided and the hydraulic circuit is simplified. Will be.

According to the third aspect of the present invention, the above-described configuration is employed for the pressure adjusting means for adjusting the engagement pressure between the two friction elements that are selectively engaged. It will be further simplified.

On the other hand, according to the fourth aspect of the invention, a friction element that is engaged at a plurality of gears with different torque transmission capacities and a pressure adjustment that regulates the engagement pressure supplied to the friction element by reducing the line pressure. In an automatic transmission provided with a means,
Since the line pressure supply means for supplying the line pressure to the drain port side of the pressure adjustment means is provided when the friction element is fastened at the gear stage having a large torque transmission capacity, the pressure adjustment means is also used in this case. As the exhaust pressure is prohibited, a high line pressure can be supplied to the friction element as the engagement pressure.

[Brief description of the drawings]

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

FIG. 2 is a circuit diagram showing a hydraulic circuit of the automatic transmission.

FIG. 3 is a control system diagram for each solenoid valve in the hydraulic circuit of FIG. 2;

FIG. 4 is an enlarged view showing a sub-transmission control portion in the hydraulic circuit of FIG. 2;

FIG. 5 is an enlarged view showing a state where the fourth and fifth shift valves are shifted to the ON state in the hydraulic circuit of FIG. 2;

FIG. 6 is a hydraulic circuit diagram showing a second embodiment.

FIG. 7 is a hydraulic circuit diagram showing a third embodiment.

FIG. 8 is a hydraulic circuit diagram showing a fourth embodiment.

FIG. 9 is a hydraulic circuit diagram showing a fifth embodiment.

[Explanation of symbols]

32 coupled clutch 34 deceleration brake 64 the fourth shift valve 95 second linear A solenoid valve 95b drain port 138 line 219 backward line

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Kazunori Enodo 3-1, Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. (56) References JP-A-4-107359 (JP, A) JP-A 3-204467 (JP, A) JP-A-58-46248 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16H 59/00-63/48

Claims (4)

(57) [Claims] 1. A control device for an automatic transmission provided with a pressure adjusting means for adjusting an engagement pressure supplied to a friction element by reducing a line pressure, wherein a bypass means for bypassing the pressure adjusting means; A control device for the automatic transmission, comprising: a pressure-reducing means for restricting a discharge pressure from a drain port provided in the pressure-regulating means when the pressure-regulating means is bypassed by the bypass means. . 2. The bypass means comprises a bypass which bypasses the pressure adjusting means, and a bypass valve provided in the bypass, and a drain port of the pressure adjusting means is connected to the bypass valve. 2. The control device for an automatic transmission according to claim 1, wherein a communication state between the drain port and a drain port provided in the valve is cut off when the pressure regulating unit is bypassed by the valve. 3. The pressure adjusting means according to claim 1, wherein a pressure adjusting means is connected to a fastening pressure supply path of the two friction elements to which the fastening pressure is selectively supplied. Control device for automatic transmission. 4. An automatic transmission provided with a friction element that is fastened at different speeds with different torque transmission capacities and pressure adjusting means for adjusting the fastening pressure supplied to the friction element by reducing the line pressure. A line pressure supply means for supplying a line pressure to a drain port side of the pressure regulating means when the friction element is fastened at a shift speed having a large torque transmission capacity. A control device for an automatic transmission, characterized by: