JP3128098B2 - Hydraulic 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 a hydraulic control device for an automatic transmission, and more particularly, to a hydraulic control device for an automatic transmission that increases a line pressure in accordance with an inertia torque during a shift-up shift. .

[0002]

2. Description of the Related Art Generally, an automatic transmission mounted on an automobile combines a torque converter to which an engine output is input and a transmission mechanism driven by the output of the converter, and has a plurality of power transmission paths of the transmission mechanism. The automatic transmission is configured to automatically shift to a predetermined gear by switching by selectively engaging the friction elements. In this type of automatic transmission, the engagement force of each friction element is controlled by hydraulic pressure. It is supposed to be. In this case, if the hydraulic pressure (line pressure) supplied to the friction element is too low relative to the input torque, the torque transmission capacity of the friction element is insufficient, and the required torque cannot be transmitted reliably. Become. Conversely, if the line pressure supplied to the friction element is too high with respect to the input torque, a so-called shift shock occurs when the friction element is fastened, and the torque for driving the oil pump becomes unnecessarily large. Engine power will be consumed unnecessarily. For this reason, it is customary to adjust the line pressure according to, for example, the throttle opening representing the engine output, thereby making the line pressure correspond to the input torque of the friction element.

[0003] By the way, at the time of gear shifting, the rotation of the transmission mechanism is adjusted in order to match the gear ratio with the target gear. In this case, for example, during a shift-up shift, torque is released to reduce the rotation of the transmission mechanism. In other words, in addition to the input torque, the inertia torque for rotation adjustment is added to the friction element involved in the shift operation, which may result in a longer shift operation time and worsening the shift feeling. is there.

[0004] In order to solve such a problem, the line pressure or the engagement pressure supplied to the friction element at the time of gear shifting is set to a pressure in which the inertia torque at the time of gear shifting is added to the input torque to the friction element. There is (for example, special publication 5
8-501277). According to this, for example, at the time of a shift-up shift, the fastening pressure supplied to the friction element increases by an amount corresponding to the inertia torque released at the time of the shift, so that the above disadvantage is avoided. become.

[0005]

By the way, in this type of automatic transmission, when a fastening pressure is supplied to a friction element during a gear shift, a shift shock due to a sudden engagement of the friction element is prevented. In some cases, an accumulator is provided in a fastening pressure supply oil passage to the friction element.

[0006] If the line pressure is increased as described above at the time of a shift-up shift in which the friction element in which the accumulator is provided in the engagement pressure supply oil path is involved in the shift operation, the following new problem occurs. Will occur.

That is, conventionally, as shown in FIG. 8, for example, when a shift condition is satisfied and a shift shift flag is set, the line pressure is controlled to increase. In this case, since there is a response delay from when the line pressure increase command is output until the line pressure actually increases, the formation of the shelf pressure by the accumulator is significantly delayed as shown by the arrow (a) in the figure. Become. Due to this delay, the torque phase in the initial stage of the shift operation becomes longer as shown by the arrow (b) in the figure, and as a result, the shift operation time becomes longer, which deteriorates the shift feeling.

According to the present invention, a hydraulic circuit for controlling the supply of the engagement pressure to the friction element is provided with an accumulator for controlling the engagement pressure to be supplied to the friction element, and is adapted to cope with an inertia torque at the time of a shift-up shift. In order to solve the above-described problem in the automatic transmission configured to increase the line pressure, the shift operation can be favorably performed even when the engagement pressure is supplied to the friction element via the accumulator during the upshift. The purpose is to be.

[0009]

That is, a hydraulic control device for an automatic transmission according to the invention of claim 1 of the present application (hereinafter referred to as a first invention) is a hydraulic circuit for controlling the supply of engagement pressure to a friction element. In an automatic transmission having an accumulator for controlling the engagement pressure supplied to the friction element and increasing the line pressure in response to the inertia torque during the shift-up shift, the automatic transmission prior to the shift-up shift A line pressure increasing means for increasing a line pressure corresponding to the inertia torque at a shift speed is provided.

The invention of claim 2 of the present application (hereinafter referred to as the second invention)
The invention relates to a hydraulic control device for an automatic transmission, comprising: a hydraulic circuit that controls the supply of a fastening pressure to a friction element; an accumulator that controls a fastening pressure supplied to the friction element; and a back pressure that is supplied to the accumulator. Back pressure control means for controlling the speed of the up-shift, and the line pressure is increased in response to the inertia torque at the time of the up-shift, in the shift stage before the up-shift,
A line pressure increasing means for increasing the line pressure according to the inertia torque is provided.

In the hydraulic control apparatus for an automatic transmission according to the third aspect of the present invention (hereinafter referred to as a third aspect), the line pressure increasing means in the first and second aspects forms a shift pattern. The present invention is characterized in that the line pressure is increased in a region near the upshift line.

[0012]

According to the above arrangement, the following operation can be obtained.

That is, in any of the first and second aspects of the present invention, the line pressure is increased in accordance with the inertia torque released at the time of the shift, even at the shift stage before the upshift. When the command is output, the increased line pressure is supplied to the friction element via the accumulator, whereby an appropriate shelf pressure is formed by the accumulator even in the initial stage of the shift operation, and the shift operation is improved. Will be performed.

[0014] In particular, according to the second aspect of the present invention, the hydraulic circuit for controlling the supply of the fastening pressure to the friction element is provided with an accumulator for controlling the fastening pressure supplied to the friction element, and the back pressure supplied to the accumulator. In the case where the back pressure control means is provided, the line pressure is increased at the time when the shift command is output, so that the responsiveness of the back pressure control means in the pressure increasing direction is improved. .

According to the third aspect of the present invention, since the line pressure is increased only in the vicinity of the shift-up shift line constituting the shift pattern, the pump loss caused by the oil pump is greatly reduced.

[0016]

Embodiments of the present invention will be described below.

As shown in FIG. 1, an automatic transmission 1 according to this embodiment has a torque converter 10, a main transmission 20 disposed 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 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 Stator 1
5, a converter output shaft 16 connected to the turbine 13, and a lock-up 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
Between 0 and 0, an oil pump 4 driven by the engine output shaft 2 via the torque converter 10 is arranged.

The main transmission 20 includes 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 anti-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 to the sun gear 2a of the rear planetary gear mechanism 22 via the direct coupling clutch 24.
2a, the sun gear 21a of the front planetary gear mechanism 21 and the ring gear 22b of the rear planetary gear mechanism 22 are connected.

Between the ring gear 21b of the front planetary gear mechanism 21 and the transmission case 3, a first one-way clutch 25 and a low reverse brake 26 are arranged in parallel. 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 the second one-way clutch 27 and the 3-4 brake 28. Then, the pinion carriers 21c, 22c of the front planetary gear mechanism 21 and the rear planetary gear mechanism 22 are connected, and the main transmission 2
An intermediate gear 5 for transmitting power from the transmission 0 to the auxiliary transmission 30 is connected.

With this 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 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 always meshing 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 connection clutch 32 is disposed between the transmission gear 3 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. And, the planetary gear mechanism 31
The output gear 7 is connected to the pinion carrier 31c, and left and right driving wheels (not shown) are connected to the output gear 7 via a differential device.
Power is transmitted to the vehicle.

The auxiliary transmission 30 can shift the power input from the main transmission 20 via the intermediate gears 5 and 6 into two forward speeds, a low speed stage and a high speed stage, and output the output power to the output gear 7. It has become.

That is, when the direct coupling clutch 32 is released, the sun gear 31 of the planetary gear mechanism 31 is actuated by the third one-way clutch 33 or the deceleration brake 34.
When b 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, 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 operates.

Further, the direct coupling clutch 32 is engaged,
When 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, so that the power from the intermediate gear 6 is output from the pinion carrier 31c to the output gear 7 as it is,
As a result, a high-speed stage (directly connected stage) is obtained.

In this manner, the main transmission 20 provides three forward speeds and one reverse speed, and the subtransmission 3
0, two high and low gear stages can be obtained with respect to the output of the main transmission 20, so that the automatic transmission 1 as a whole has six gear stages for the forward movement, and The combination of the reverse gear of the transmission 20 and the lower gear of the auxiliary transmission 30 to which the deceleration brake 34 is engaged provides the overall reverse gear. And in this example,
As the forward gear, five predetermined gears out of the six gears are adopted.

The operating states of the clutches and brakes at each of the five forward speeds and one reverse speed are summarized in Table 1. In Table 1, (○) indicates that the vehicle is engaged only in the engine brake range.

[0029]

[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
Among them, 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. The control pressure adjusted by the duty solenoid valve 49 is supplied to the control port 48a of the modulator valve 48.
A modulator pressure is generated from the control source pressure in accordance with a duty ratio of 9 (a ratio of ON time during 1 ON and OFF cycles), and the modulator pressure is applied to a first pressure increase of the regulator valve 41 via a line 50. Port 4
1a, whereby the line pressure is increased in accordance with the duty ratio. In this case, by setting the duty ratio based on the engine output, the line pressure is adjusted to a value corresponding to the engine output.

A line 5 for supplying the modulator pressure to the first pressure increasing port 41a of the regulator valve 41
0, the periodic O of the duty solenoid valve 49
A first accumulator 51 for suppressing hydraulic pulsation caused by the N, OFF operation is provided.

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 line 52, and in the R range, the main line 42 is connected to the reverse line 53.

The forward line 52 is guided to the forward clutch 23 through an orifice 54 having a different throttle amount between the time of supply and discharge of hydraulic oil.
In each of the forward ranges 3, 2, and 1, the forward clutch 23 is always engaged. In this case, a second accumulator 55 for reducing a shock at the time of supplying the engagement pressure to the forward clutch 23 is installed in the forward line 52, and the second accumulator 55 is connected to the accumulator 55 via the line 56 from the main line 42. Back pressure is supplied.

Here, first and second hydraulic chambers 32a and 32b having different pressure receiving areas are provided as hydraulic chambers of the direct coupling clutch 32 in the auxiliary transmission 30.
When the same fastening pressure is introduced into 2a and 32b, when the fastening pressure is introduced into the first hydraulic chamber 32a having a large pressure receiving area, the fastening pressure is introduced into the second hydraulic chamber 32b having a small pressure receiving area. It is designed to obtain a larger fastening force than in the case where it is performed.

The deceleration brake 34 is also provided with first and second hydraulic chambers 34a and 34b having different pressure receiving areas. When the same fastening pressure is introduced into these hydraulic chambers 34a and 34b, First hydraulic chamber 3 with large pressure receiving area
When the fastening pressure is introduced into 4a, a greater fastening force is obtained than when the fastening pressure is introduced into the second hydraulic chamber 34b having a smaller pressure receiving area.

The retreat line 53 is directly led to the first hydraulic chamber 34a of the auxiliary transmission 30 where the pressure receiving area of the deceleration brake 34 is large. Therefore, in the R range, the first hydraulic chamber 34a is connected to the first hydraulic chamber 34a. Due to the introduced line pressure, the deceleration brake 34 is fastened with a large fastening force. A line 57 leading to the second pressure increasing port 41b of the regulator valve 41 is branched from the retreat line 53 so that 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 the fourth and fifth shift valves 64 and 65 for shifting in the subtransmission 30 are supplied with line pressure.

Each of the shift valves 61 to 65 has a control port 61 a to 65 a 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 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, respectively. These ON-OFF solenoid valves 71 to
Numeral 75 drains the inside of the control ports 61a to 65a of the shift valves 61 to 65 at the time of ON. Therefore, the spools of the shift valves 61 to 65 are provided with the corresponding ON-OFF solenoid valves 71 to 75.
Is on the left side of the drawing when is ON, and is on the right side when OFF.

The solenoid valves 71 to 71
75 ON / OFF combination, that is, each shift valve 61
According to the combination of the spool positions of ~ 65, the lines leading to the respective clutches and brakes from the main line 42, the forward line 52 or the reverse line 53 are selectively communicated. When the clutch and the brake are engaged, the first to fifth speeds and the reverse speed are obtained. In this 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, coast brake 29, low reverse brake 26 and 3-4 brake 28 in the main transmission 20, a control valve 76 for reducing the line pressure to adjust it to a predetermined engagement pressure is provided. 77, 78, and 79, respectively, of which control valves 77, 7 for coast brake, low reverse brake, and 3-4 brake.
8, 79, the control ports 77a, 78a, 79
The control pressure adjusted by the first linear solenoid valve 80 is supplied to a through a line 81, and the engagement pressure is controlled in accordance with the control pressure.

The control pressure 76a of the direct-coupled clutch control valve 76 controls the engagement pressure supplied to the direct-coupled clutch 24 by a line 82 via a line 85 provided with a one-way orifice 83 and a third accumulator 84. The pressure 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
0 is the line 4 from the first reducing valve 44
The control source pressure supplied via the controller 7 is adjusted in accordance with a control signal from a controller (see FIG. 3) to generate a control pressure corresponding to a shift speed and an operating state at that time. Further, the control valve 76 for the direct coupling clutch is used.
And the low reverse brake control valve 7
The ports 76b and 78b provided at one end of the pressure control line 8 are provided with the pressure regulating operation prohibiting lines 8 branched from the retreat line 53.
6 are connected, and in the R range, these ports 7
The line pressure is supplied to the control valves 7b and 78b, and the spool is fixed at the left position in the drawing.
6,782 pressure regulating operations are prevented. Further, when fastening pressure is supplied to the coast brake 29, the fastening pressure is supplied to a port 79b at one end of the 3-4 brake control valve 79 through a line 87, and the control valve 79 is controlled. The pressure operation is restricted.

The first linear solenoid valve 8
0 is applied to the control port 8 of the accumulator control valve 88 via line 81.
8a. The control valve 88 adjusts the line pressure supplied from the main line 42 via the line 89 in accordance with the control pressure from the first linear solenoid valve 80, and adjusts the line pressure for the third accumulator 84 and the fourth accumulator 90. , And this is applied by line 91 to both accumulators 8
4, 90 are supplied to the back pressure ports 84a, 90a.

On the other hand, for controlling the engagement pressure in the sub-transmission 30, the first direct coupling clutch 32 having a large pressure receiving area is used.
The control valve 101 for the direct coupling clutch that adjusts the engagement pressure supplied to the hydraulic chamber 32a and the second hydraulic chamber 32b having a small pressure receiving area, and the engagement pressure supplied to the second hydraulic chamber 34b having a small pressure reception area of the deceleration brake 34 A deceleration brake control valve 102 to be adjusted and a second linear solenoid valve 103 are provided. As described above, the line pressure is directly supplied from the manual valve 43 via the retreat line 53 to the first hydraulic chamber 34a having a large pressure receiving area of the deceleration brake 34 in the R range.

The second linear solenoid valve 103
Means that the line pressure is supplied from the main line 42 as the control source pressure.
Which is adjusted in response to a control signal from the controller.
After setting, the line 104 and the fifth shift valve 65
Deceleration via line 105 or line 106
Control port 10 of brake control valve 102
2a, or the first hydraulic chamber of the direct-coupled clutch 32
32a and the hydraulic chamber 32 Adjust the hydraulic pressure of a. So
The control valve 102 for the deceleration brake
Is the second linear solenoid valve 10 as described above.
3 is supplied to the control port 102a.
The main line 42 to the line 107,
Four shift valve 64, line 108, fifth shift valve
65 and the line pressure supplied via line 109
The pressure is adjusted according to the control pressure, and is adjusted via the line 110.
It is supplied to the second hydraulic chamber 34b of the deceleration brake 34.

On the other hand, the direct-coupled clutch control valve 101 is connected to the main line 42 through the line 107,
The line pressure is supplied through the shift valve 64 and the line 111, and after adjusting this, the one-way orifice 1
12, the first hydraulic chamber 32a or the second hydraulic chamber 32b of the direct coupling clutch 32 from the line 113 and the fifth shift valve 65 through the line 106 or the line 114.
To be supplied selectively.

The first hydraulic chamber 32a or the second hydraulic chamber 32b of the direct coupling clutch 32 is connected to the control port 101a of the direct coupling clutch control valve 101.
Is supplied to the one-way orifice 11
Line 1 provided with fifth and fifth accumulators 116
17 is supplied as a control pressure, and therefore, the fastening pressure is controlled by the fifth accumulator 1.
By the operation of No. 16, it rises through a certain shelf pressure state. The back pressure is supplied from the main line 42 to the back pressure port 116a of the accumulator 116 via the line 118.

In the hydraulic circuit 40 having the above configuration, the first to fifth ON-OFF solenoid valves 71 to 7
The combination pattern of ON and OFF of No. 5 is as shown in Table 2, whereby the first to fifth forward speeds 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.

[0051]

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

First, at the first speed in which the engine brake employed in the D range or the like does not operate, the main transmission 20 side
The first to third ON-OFF solenoid valves 71 to 73 are ON, OFF, and OFF, and 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 121 branched from the forward line 52 communicates with the line 122 via the first shift valve 61, and further the second shift valve 6
2 through line 123, but this line
3 is shut off by the third shift valve 63. The other line 124 branched from the forward line 52 is also the second line 124.
In the shift valve 62, the lines 125 branched from the main line 42 are shut off by the first shift valve 61, respectively. Therefore, in this case, as described above, only the forward clutch 23 that is always engaged in the forward range is engaged, and a low speed stage in which the engine brake does not operate in the main transmission 20 is obtained.

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 is 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 the control valve 10 for the deceleration brake via the fifth shift valve 65.
2, a line pressure is supplied to the control valve 102. 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 controlled. Is adjusted according to the control pressure, and after a predetermined fastening pressure,
The second hydraulic chamber 3 of the deceleration brake 34 via the line 110
4b, and the deceleration brake 34 is engaged.

The direct coupling clutch 32 is connected to the first hydraulic chamber 3.
2a is line 106, fifth shift valve 65, line 1
13, communicates with the drain port of the fourth shift valve 64 via the direct-coupled clutch control valve 101 and the line 111, and the second hydraulic chamber 32b
Is released by communicating with the drain port of the fifth shift valve 65 through the. As a result, the shift speed of the sub-transmission 30 becomes the low speed at which the engine brake operates, and the entire automatic transmission becomes the first speed at which the engine brake does not operate.

In the first speed in which the engine brake employed in the first range or the second range is operated, the third solenoid valve 73 in the main transmission 20 is turned on with respect to the first speed in which the engine brake is not operated, Accordingly, the spool of the third shift valve 63 is located on the left side. Therefore, in this case, the advance line 52 is
The branch line 121, the first shift valve 61, the line 122, the second shift valve 62, the line 123 and the third
The line pressure is supplied to the control valve 78 through a line 126 communicating with the low reverse brake control valve 78 via the shift valve 63.

The line pressure supplied to the control valve 78 is applied to the first linear solenoid valve 80.
Is adjusted to a fastening pressure corresponding to the control pressure supplied to the control port 78a via the line 81 from the
It is supplied to a low reverse brake 26 via a switch 27.
As a result, in addition to the forward clutch 23, the low reverse brake 26 is engaged, and a low speed stage in which the engine brake operates in the main transmission 20 is obtained.
In the sub-transmission 30, the deceleration brake 34 is engaged as in the case of the first speed in which the engine brake is not operated, so that the first speed in which the engine brake is operated is obtained as the entire automatic transmission.

Next, in the second speed in which the engine brake is not operated in the D range or the like, and in the second speed in the engine brake operation used in the first range or the second range, the first speed and the second speed in the non-operated state of the engine brake are used. Only the shift speed of the auxiliary transmission 30 changes with respect to the first speed state of the engine brake operation.

That is, the fourth ON-
The OFF solenoid valve 74 is turned ON, and accordingly, the spool of the fourth shift valve 64 is located on the left side.
Accordingly, 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-coupled clutch control valve 101 via the line 111, and After the rise is adjusted by the valve 101, the first hydraulic chamber 32 of the direct coupling clutch 32 is connected via the line 113, the fifth shift valve 65 and the line 106.
a. Thereby, the auxiliary transmission 30
Becomes the second gear, and as a result, as a whole of the automatic transmission, the second gear in which the engine brake does not operate or the second gear in which the engine brake operates is obtained.

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 121 from the forward line 52 communicates with the line 128 via the first shift valve 61, and further a line 129 which communicates with the coast brake control valve 77 via the third shift valve 63. Communicate with Accordingly, a line pressure is supplied to the control valve 77, and the pressure is adjusted to a predetermined fastening pressure in accordance with the control pressure supplied from the first linear solenoid valve 80 via the line 81, and then is adjusted via the line 130. The coast brake 29 is supplied to the coast brake 29.
Is concluded.

Further, 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 to supply 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 an engagement 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, a middle gear in which the engine brake operates is obtained.

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 low speed at which the engine brake operates as in the case of the first speed described above. 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.

In the fourth speed, the fourth and fifth ON-OFF solenoid valves 74 and 75 of the auxiliary transmission 30 are turned ON from the state of the third speed, and the fourth and fifth shift valves 64 and 65 are turned on. The spool is located on the left side, so that the line pressure is first controlled from the main line 42 through the line 107, the fourth shift valve 64, and the line 111 as in the case of the second speed. And the control valve 1
The rise is adjusted at 01, and the specified fastening 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-coupled clutch 32
b. As a result, the direct coupling clutch 3
2 is engaged, and the speed stage of the subtransmission 30 becomes the high speed stage.
Since the main transmission 20 is set to the middle speed as in the case of the third speed, the speed of the entire automatic transmission is the fourth speed.

Further, at the fifth speed, the first to third ON-OFF solenoid valves 71 to
73 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 125 branched from the main line 42 is connected to the line 13 via the first shift valve 61.
3, and further communicates with a line 134 that 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. And
The engagement pressure adjusted by the control valve 76 is supplied to the direct coupling clutch 24 via the line 82, and the clutch 24 is engaged. Thereby, the main transmission 20
In, the forward clutch 23 and the direct coupling clutch 24 are engaged, and the shift speed is set to the high speed. When the direct coupling clutch 24 is engaged, the engagement pressure is supplied through a predetermined shelf pressure state by the action of the third accumulator 84.

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 fourth speed.
Both the gears 4 and 75 are in the ON state, and the shift speed is set to the high speed stage. As a result, the automatic transmission as a whole can obtain the fifth speed.

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 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.

For this reason, first, the line 125 branched from the main line 42 is, as in the case of the fifth speed described above,
A line 134 communicates with the line 133 via the first shift valve 61, and further communicates with the direct-coupled clutch control valve 76 via the third shift valve 63.
Therefore, the 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 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 supplied to the direct coupling clutch 24 via the line 82 without being reduced in pressure, and the direct coupling clutch 24 is engaged with a high engagement pressure.

The retreat line 53 has an orifice 135 having a different throttle amount in the supply and discharge directions of the hydraulic oil.
The low reverse brake control valve 78 is communicated via the line 136, the third shift valve 63, and the above-mentioned line 126, and the control valve 78 is operated in the same manner as in the case of the first speed of the engine brake operation.
Supply line pressure to In this case, the port 78b at one end of the control valve 78 is connected to the retreat line 53.
When the line pressure is introduced by the line 86 branched from the control valve 78, the spool of the control valve 78 is fixed to the left side in the drawing. Therefore, the line 12
6 is supplied to the low reverse brake 26 without being adjusted by the control valve 78, and the line pressure supplied by the low reverse brake 2
6 is 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 sub-transmission 30, the fourth and fifth ON-OFF solenoid valves 74, 7
5 are both OFF and the speed is set to the low speed at which the engine brake operates, and a reverse speed with a large reduction ratio can be obtained.

When the engagement pressure is supplied to the low reverse brake 26, the operating oil is introduced into the fourth accumulator 90 from the line 136 via the line 137, so that the engagement pressure is reduced to a predetermined value. It will gradually rise after the shelf pressure state.

In addition to the above configuration, the hydraulic circuit 40 includes a lock-up clutch 1 in the torque converter 10.
, A lock-up control valve 143, an ON-OFF solenoid valve 144 for lock-up control, and a duty solenoid valve 145.
The engagement and release control of the lock-up clutch 17 and the slip control for slipping the clutch 17 are performed.

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 80 and 103 for adjusting the fastening pressure, ON-OFF solenoid valve 144 for lock-up control, and duty solenoid valve 1
45 is controlled by a control signal from the controller 160 as shown in FIG. The controller 160 detects a signal from a vehicle speed sensor 161 for detecting a vehicle speed, a signal from a throttle opening sensor 162 for detecting an engine throttle opening, and a shift position (range) selected by the driver. A signal from the shift position sensor 163, a signal from the air flow sensor 164 for detecting the amount of intake air of the engine, a signal from the engine rotation sensor 165 for detecting the engine speed, the input-side speed of the main transmission 20 (turbine speed) ) From the turbine rotation sensor 166 to detect
A signal from an intermediate rotation sensor 167 for detecting the rotation speed of the output side of the main transmission 20 (the input side of the subtransmission 30) and the output rotation sensor 1 for detecting the rotation speed of the output side of the subtransmission 30
Signals and the like from 68 are input, and each of the solenoid valves is controlled in accordance with an operating state indicated by these signals or a driver's request.

The automatic transmission according to the present embodiment is configured as described above. In this automatic transmission, as apparent from the above description, for example, at the time of the 1-2 shift-up shift, the auxiliary transmission 30 The engagement pressure is supplied to the first hydraulic chamber 32a of the direct connection clutch 32 through the accumulator 116.

That is, at the first speed, as described above, in the auxiliary transmission 30, the fourth and fifth ON-OFF solenoid valves 74 and 75 are both in the OFF state, and the fourth and fifth shift valves 64 and 75 are in the OFF state. Since the 65 spools are located on the right side, the main line 42 to the line 107, the fourth
Shift valve 64, line 108, fifth shift valve 6
5 and the line pressure is supplied to the deceleration brake control valve 102 via the line 109, and this is supplied to the second linear solenoid valve 10 by the control valve 102.
After being adjusted according to the control pressure from line 3, line 110
Is supplied to the second hydraulic chamber 34b of the deceleration brake 34 via the second brake chamber 34, whereby the deceleration brake 34 is engaged, that is, in a low speed state.

At this time, the first hydraulic chamber 32a of the direct connection clutch 32 is connected to the first drain of the fourth shift valve 64 via the line 106, the fifth shift valve 65, the line 113, the control valve 101 for the direct connection clutch, and the line 111. The second hydraulic chamber 3 communicates with the port 64b.
2b communicates with the first drain port 65b of the fifth shift valve 65 via the line 114.

When the fourth and fifth ON-OFF solenoid valves 74 and 75 of the auxiliary transmission 30 are turned ON and OFF when shifting from this state to the second speed, the spool of the fourth shift valve 64 moves to the left. Then, the spool of the fifth shift valve 65 is located on the right side.

This state is as shown in FIG. 4. In this case, the fourth line is connected from the main line 42 through the line 107.
The line pressure supplied to the shift valve 64 is supplied from the fourth shift valve 64 to the direct-coupled clutch control valve 101 via the line 111. The line pressure is further supplied from the control valve 101 to the one-way orifice 112 and the line 113. Is supplied to the first hydraulic chamber 32a of the direct coupling clutch 32 via the fifth shift valve 65 and the line 106, and the direct coupling clutch 32 is engaged.
At this time, the second hydraulic chamber 34b of the deceleration brake 34
Is connected to the second drain port 64c of the fourth shift valve 64 via the line 110, the control valve 102 for deceleration brake, the line 109, the fifth shift valve 65, and the line 108.

As a result, the shift stage of the subtransmission 30 becomes a high speed stage, and the 1-2 shift is completed.
When the engagement pressure is supplied to the first hydraulic chamber 32a of the direct connection clutch 32 at the time of the -2 shift, the rise thereof is controlled as follows.

That is, the line pressure supplied from the fourth shift valve 64 to the directly connected clutch control valve 101 is applied to the control port 101 of the control valve 101.
The hydraulic oil output from the control valve 101 itself is supplied to the control port 101a via the one-way orifices 112 and 115 via the line 117 and the accumulator 116 is connected to the control port 101a. After actuation, it is supplied as control pressure.

In this case, if the line pressure is increased at the same time as the 1-2 shift command, the shelf pressure in the initial stage of the shift operation will not be properly formed due to a response delay.

Therefore, in this embodiment, the above-mentioned inconvenience is avoided by controlling the line pressure according to, for example, a flowchart shown in FIG.

That is, the controller 160 determines in step S
1 to read various signals and then execute step S2
To determine whether the operating state indicating the engine speed and the throttle opening belongs to the predetermined pressure increasing zone.
The pressure increase zone is indicated by hatching in FIG.
Shift-up shift line L1 constituting shift pattern
2, L23, L34, and L45 are set on the lower vehicle speed side.

When the controller 160 determines that the operation region belongs to the pressure increasing zone, the process proceeds to step S3, and the target line pressure is set based on the turbine torque. Here, the turbine torque is obtained as follows.

That is, the controller 160 takes in the signals from the airflow sensor 164 and the engine rotation sensor 165 to calculate the charging efficiency, and then calculates the charging efficiency based on the charging efficiency and the engine speed indicated by the signal from the sensor 165. Estimate engine torque representative of engine output. Further, the controller 160 takes in a signal from the turbine rotation sensor 166, calculates a speed ratio of the torque converter 10 based on the turbine speed indicated by the signal and the engine speed, and then calculates a speed ratio based on the speed ratio. Calculate the torque increase ratio. Then, the turbine torque is finally determined by multiplying the engine torque by the torque increase ratio.

Next, the controller 160 executes step S4 to set the increased line pressure. This increased line pressure is set as follows. That is, the controller 160 determines the target turbine speed change amount as a substitute characteristic of the inertia torque, based on the gear ratio of the shift speed at that time and the gear ratio of the shift speed after the upshift. Then, the amount of change in the target turbine speed is compared with a preset map of the increased line pressure to set the increased line pressure corresponding to the amount of change. In this case, the map is set such that the increased line pressure increases as the target turbine speed change amount increases.

Then, the controller 160 proceeds to step S
5 is executed to determine the final target line pressure from the target line pressure and the increased line pressure, and a control signal is sent to the duty solenoid valve 49 for line pressure control so that the target line pressure is obtained in step S6. Output.

On the other hand, when the controller 160 determines in step S2 that the operation state does not belong to the image pressure zone, the process proceeds to step S7 to determine whether or not the shift flag Fs for shifting is set to 1 indicating the shift state. Is determined, and when the determination is YES, the process returns to the step S3 and executes the following steps.

When the controller 160 determines that the shift flag Fs is not set to 1 in step S7, the controller 160 executes step S8 to set the target line pressure based on the turbine torque as in step S3. Then, the process proceeds to step S6 to output a control signal to the duty solenoid valve 49 so that the target line pressure is obtained.

Next, the operation of the embodiment will be described.

Now, it is assumed that the shift speed is the first speed. And
For example, if the driving state shifts to the pressure increasing zone set on the low vehicle speed side of the 1-2 shift up line L12 due to an increase in the vehicle speed, the line pressure is increased at that time as shown in FIG. It will rise in response to the increased line pressure.

When the vehicle speed further increases and passes through the 1-2 shift up line L12, the shift flag Fs is set to 1 and the 1-2 shift operation is started. In this case, the arrow (A) ), The line pressure has already been increased. Therefore, as shown by the arrow (a) in the figure, the fastening pressure quickly shifts to the shelf pressure state by the action of the accumulator 116 and the like.
As a result, the output shaft torque in the torque phase at the initial stage of the gear shift temporarily decreases as shown by the arrow (c), and then increases as quickly as possible. Become.

The shift flag Fs is reset to 0 in accordance with the completion of the shift operation, and the line pressure is returned to the normal line pressure accordingly.

By the way, as shown in FIG.
The back pressure of the accumulator 84 used when supplying the engagement pressure to the direct coupling clutch 24 at 0 is adjusted by controlling the control pressure supplied to the control port 88a of the accumulator control valve 88 by the first linear solenoid valve 80. Is to be done. Therefore, at the time of the 4-5 shift-up shift in which the direct coupling clutch 24 is engaged, the responsiveness in the pressure increasing direction is improved by increasing the line pressure in advance before the actual shift operation is performed as described above. Will be.

[0094]

As described above, according to the present invention, the hydraulic circuit for controlling the supply of the engagement pressure to the friction element is provided with the accumulator for controlling the engagement pressure to be supplied to the friction element, and at the time of shift-up shifting. In an automatic transmission in which the line pressure is increased in accordance with the inertia torque during the shift, the line pressure is increased according to the inertia torque released during the shift even at the shift speed before the upshift. Therefore, when the gearshift command is output, the increased line pressure is supplied to the friction element via the accumulator, whereby an appropriate shelf pressure is formed by the accumulator even at the beginning of the gearshift operation. Thus, the shifting operation is performed favorably.

In particular, according to the second aspect of the present invention, the hydraulic circuit for controlling the supply of the fastening pressure to the friction element includes the accumulator for controlling the fastening pressure supplied to the friction element, and the back pressure supplied to the accumulator. In the case where the back pressure control means is provided, the line pressure is increased at the time when the shift command is output, so that the responsiveness of the back pressure control means in the pressure increasing direction is improved. .

By increasing the line pressure in the vicinity of the shift-up shift line forming the shift pattern as in the embodiment, there is an advantage that the pump loss due to the oil pump is greatly reduced.

[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 a diagram illustrating a sub-transmission control part 1- in the hydraulic circuit;
FIG. 4 is a circuit diagram showing a state at the time of two shifts.

FIG. 5 is a flowchart illustrating line pressure control according to the embodiment.

FIG. 6 is an operation area diagram showing a shift-up shift pattern.

FIG. 7 is a time chart illustrating the operation of the embodiment.

FIG. 8 is a time chart showing a conventional problem.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Automatic transmission 20 Main transmission 24 Direct connection clutch 30 Secondary transmission 32 Direct connection clutch 41 Regulator valve 48 Modulator valve 49 Duty solenoid valve 80 First linear solenoid valve 84 Third accumulator 88 Control valve for accumulator 116 Accumulator 160 Controller 161 Vehicle speed sensor 162 Throttle opening sensor 164 Air flow sensor 165 Engine rotation sensor 166 Turbine rotation sensor

Claims (3)

(57) [Claims] A hydraulic circuit for controlling the supply of a fastening pressure to a friction element is provided with an accumulator for controlling a fastening pressure to be supplied to the friction element. A hydraulic control device for an automatic transmission adapted to increase a line pressure, wherein a line pressure increasing means for increasing a line pressure corresponding to the inertia torque is provided at a shift speed before an upshift. A hydraulic control device for an automatic transmission, characterized in that: 2. A hydraulic circuit for controlling the supply of a fastening pressure to a friction element, comprising: an accumulator for controlling a fastening pressure to be supplied to the friction element; and a back pressure control means for controlling a back pressure to be supplied to the accumulator. A hydraulic control device for an automatic transmission, comprising: a shift stage that shifts up a line pressure corresponding to an inertia torque at the time of a shift-up shift. And a line pressure increasing means for increasing the line pressure. 3. The line pressure increasing means according to claim 1, wherein the line pressure increasing means is configured to increase the line pressure in a region near a shift-up shift line constituting a shift pattern. 2. The hydraulic control device for an automatic transmission according to claim 1.