JP3458618B2 - Selective shock reduction 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 select shock reducing device for reducing a shock when the automatic transmission is selected from a non-running range to a running range.

[0002]

2. Description of the Related Art In an automatic transmission, while a manual valve is in a travel range, a corresponding gear is selected and operated by selectively hydraulically operating (engaging) a plurality of friction elements (friction clutches and friction brakes). By changing the friction element, the gear is changed to another gear.

As a shift control device for controlling the shift of the automatic transmission, as described in Japanese Patent Laid-Open No. 63-210443, the operating pressures of a plurality of friction elements are individually electronically controlled to a predetermined value. When using a gear shift control device that is capable of performing gear shifting, it is possible to simplify the configuration of the hydraulic circuit and to enable fine-tuned operating pressure control of friction elements that is suitable for all running conditions. Is advantageous in that

In such a speed change control device, as described in, for example, Japanese Patent Laid-Open No. 3-28571, the starting friction to be engaged at the time of a select operation for switching the manual valve from the non-running range to the running range. By gradually increasing the operating pressure of the element by electronic control, the engagement of the start-up friction element is gradually advanced, whereby it is possible to easily take a measure to reduce the select shock during the select operation.

With the aim of reducing such select shock
The operating pressure control of the starting friction element is described below with reference to FIG.
As explained in the manual valve non-travel (N) range
From the moment t when the select operation is performed from the₁From
Predetermined Δt_pControl command for operating pressure of starting friction element during time
S_cTo a high value for precharge, then return
Instantaneous t after maintaining the pulling equivalent pressure command value₂More gradually
The operating pressure P of the starting friction element is increased by gradually increasing
_cIs gradually increased, whereby the start-up friction element is gradually tightened.
To the start of the selection friction with the fastening of the starting friction element.
The aim is to reduce knocks.

By the way, in the case of individually controlling the operating pressure of each friction element, generally, as shown in FIG. 11, the pilot pressure obtained by reducing the line pressure P _L which is the pressure source of the automatic transmission to a constant value. The pressure P _p is created, and this is used as the original pressure to create an electronic control pressure (not shown in FIG. 11) according to the operating pressure control command S _c . Then, it is common practice to individually control the operating pressures of the friction elements by the valves that use the electronically controlled pressure as a signal pressure.

[0007]

However, in the shift control device of the automatic transmission, since the operating pressure circuit of the starting friction element has a relatively large volume,
Especially when air is mixed in the working pressure circuit,
At the time of the above selection operation, a large amount of working fluid may be consumed to operate the starting friction element, and a situation may occur in which the pump discharge amount cannot cover this.

In this case, the line pressure P _L using the discharge fluid of the pump as a medium transiently drops as shown by α in FIG. 11, and the pilot pressure P _p satisfies the specified value corresponding to the above constant pressure. In some cases, the pilot pressure P _p itself may fall below the specified value due to the influence.

At this time, in spite of the above operating pressure control command S _c , the electronic control pressure corresponding to this is not generated, and the operating pressure of the starting friction element does not rise as intended, and as the operating pressure P _c of the starting frictional element is to rise 11, recovered to the line pressure P _L is the same value as the specified value of the pilot pressure P _p, the pilot pressure P _p is defined It was time to return to a constant pressure.

The delay in the generation of the starting friction element operating pressure P _c is determined by the engagement of the starting friction element, as is clear from the change tendency of the engine speed N _e and the waveform of the transmission output torque T _o shown in FIG. Not only does it cause a shock and the effect of reducing the select shock is not obtained, but it also makes it impossible to wipe out the harmful effects of the select shock becoming larger than when no shock measures are taken.

According to the present invention, the above problem is caused by delaying the operating pressure control command for the starting friction element while the line pressure is reduced due to the selection operation from the non-running range to the running range. It is an object of the present invention to propose a select shock reducing device for an automatic transmission that does not include the above.

[0012]

To this end, in a select shock reducing device for an automatic transmission according to a first aspect of the present invention, a plurality of friction elements are selectively engaged by fluid pressure in a traveling range. Determines the selected shift speed of the speed change gear mechanism, and gradually adjusts the fluid pressure of the starting friction element to be engaged during the select operation from the non-running range to the running range by the electronic control pressure with the line pressure as the original pressure. by raising the, against the automatic transmission so as to reduce the select shock, adds the following configuration.

That is, the selection of the automatic transmission according to the first aspect of the invention.
The shock absorber reduces the fluid pressure of the starting friction element.
The control command for the electronic control pressure that gradually increases
The output will be delayed for a predetermined time from the moment of operation
Configure

Select shock reducing device according to the first invention
Further, the predetermined time for the delay, according to the rotational speed of the engine at the front stage of the automatic transmission, is characterized in that it has a long lower the engine speed.

[0015] select shock reduction apparatus for an automatic transmission according to the second invention described in claim 2, the Te placed <br/> the first shot bright, the predetermined time, depending on the hydraulic oil temperature of the automatic transmission The feature is that the higher the temperature, the longer.

[0016] select shock reduction apparatus for an automatic transmission according to the third invention according to claim 3, in the first invention, created so that reduction of the line pressure at the time of the select operation, or from the line pressure and a constant pressure And a pressure drop detecting means for detecting a decrease in pilot pressure used as a source pressure of the electronic control pressure during a select operation, and delaying the control command while the pressure drop is detected by the means. It is characterized by having done.

The select shock reduction apparatus for an automatic transmission according to the fourth invention described in claim 4 is as follows the pressure drop detecting means in the third invention, that is, the pilot pressure corresponding to the constant pressure It is characterized in that it is configured to judge that the pressure has dropped when the specified value is not satisfied.

The select shock reduction apparatus for an automatic transmission according to the fifth invention described in claim 5, the third aspect or the fourth
In the invention, the control command is delayed until the set time elapses from the instant of the selection operation even if the pressure drop detecting means does not detect the pressure drop.

[0019]

According to the first aspect of the invention, the automatic transmission determines the selected shift stage of the transmission gear mechanism by selectively engaging a plurality of friction elements with fluid pressure during the traveling range.

Here, the select shock reducing device gradually increases the fluid pressure of the starting friction element to be engaged during the select operation from the non-running range to the running range by the electronic control pressure with the line pressure as the original pressure. Thus, the selection shock can be reduced by gradually advancing the engagement of the starting friction element.

[0021] Incidentally, especially in the first invention, the control command of the electronic control pressure gradually increasing the fluid pressure of the starting frictional element starts outputting by the selecting operation instantaneously only delay but a predetermined time. Therefore, while the line pressure, which is the original pressure of the electronically controlled pressure at the time of the selection operation, decreases while the fluid pressure control of the starting friction element cannot be performed as intended, it is possible to prevent the control from being forced. It is possible,
It is possible to avoid the deterioration of the select shock that occurs when the control is forced.

Furthermore in the first invention, the predetermined time for the delay of the control command, d in the preceding stage of the automatic transmission
Depending on the engine speed, the lower the engine speed, the longer
Because the co and the control of the delay, will be obtained without easily under time management, the cost on highly advantageous
In addition, due to the setting of the above-mentioned predetermined time, the following operational effects are also achieved.
It can be obtained .

That is, a predetermined value for delaying the control command is given.
The lower the engine speed, the longer the time.
Is the pump engine driven for discharging a fluid which is a medium of the line pressure, is under low engine speed becomes possible to improve consistent for a long time for the pressure drop, even under any engine speed There is an advantage that the above effects can be achieved.

In the second aspect of the invention, the predetermined time in the first aspect of the invention is set longer as the temperature is higher in accordance with the temperature of the hydraulic fluid of the automatic transmission. In accord with the lengthening, there is an advantage that the above-mentioned action and effect can be achieved under any hydraulic oil temperature.

In the third invention, the delay of the control command in the first invention is carried out as follows. That is, the pressure drop detecting means is designed to reduce the line pressure during the select operation, or to create a constant pressure from the line pressure, and reduce the pilot pressure used as the source pressure of the electronic control pressure during the select operation. During the detection, the control command is delayed.

In this case, the delay of the control command is detected by detecting the fact that the line pressure, which is the original pressure of the electronically controlled pressure during the selection operation, decreases so that the fluid pressure control of the starting friction element cannot be performed as intended. Since it is performed, it is possible to achieve the action and effect of the first aspect of the invention more reliably by eliminating the adverse effect that the delay of the control command is unnecessarily performed or is not performed although it is necessary. You can

In the fourth aspect of the invention, the pressure drop detecting means determines that the pressure has dropped when the pilot pressure does not reach the specified value corresponding to the constant pressure, and therefore is the original pressure of the electronic control pressure during the select operation. The fact that the line pressure has decreased so that the fluid pressure control of the starting friction element cannot be performed as intended can be detected more reliably.
It is possible to further secure the above-mentioned effects of the invention.

In the fifth aspect of the invention, even if the pressure drop detecting means does not detect the pressure drop, the control command is delayed from the instant of the selection operation until the set time elapses. In the case where there is a time delay between the operation and the pressure drop, it is possible to eliminate the adverse effect that the control command is not delayed during the time delay, and to further secure the above-described action and effect. .

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a speed change gear mechanism that forms a power transmission train of an automatic transmission to which a select shock reducing device according to an embodiment of the present invention is applied, and FIG. 2 shows engagement of a plurality of friction elements in the power transmission train. A logical table is shown.

The transmission train of the transmission gear mechanism shown in FIG. 1 has been developed by the applicant of the present application and is in practical use. "NISSAN Maxima New Vehicle Manual," Introduction of Changes to J30 Type Cars ", August 1991 (FOO7671) The input shaft I / S to which rotational power is transmitted from the crankshaft C / S of the engine ENG via the torque converter T / C, and the output shaft O / arranged coaxially therewith. The first planetary gear set G1 and the second planetary gear set G2 are provided coaxially on these input / output shafts, and various friction elements described later.

The torque converter T / C has a lockup clutch L / C, and when the working fluid is passed through the torque converter T / C, the working fluid is passed from the apply chamber AP to the release chamber RE. When the lockup clutch L / C is engaged, the torque converter T / C
However, the torque converter T / C releases the direct connection between the input / output elements by releasing the lockup clutch L / C when the working fluid flows in the reverse direction in a lockup state where the input / output elements are directly connected. The converter shall be in the opened state.

The first planetary gear set G1 includes a sun gear S1, a ring gear R1, a pinion P1 meshing with these, and a pinion carrier PC1 rotatably supporting the pinion P1.
A normal planetary gear set consisting of a second planetary gear set G
2 is also a simple planetary gear set including a sun gear S2, a ring gear R2, a pinion P2, and a pinion carrier PC2.

Next, the first to third clutches C1, C2 and C3, which are various frictional elements controlling the shift control, and the first and second clutches.
Brake B1, B2, and one-way clutch OWC
Will be explained. The carrier PC1 can be appropriately connected to the input shaft I / S via the second clutch C2, the sun gear S1 can be appropriately fixed by the second brake B2, and can be appropriately connected to the input shaft I / S by the first clutch C1. And The carrier PC1 can be further appropriately fixed by the first brake B1 and prevents reverse rotation (rotation in the direction opposite to the engine) via the one-way clutch OWC. The ring gear R1 is integrally connected to the carrier PC2 and drivingly connected to the output shaft O / S, and the sun gear S2 is connected to the input shaft I / S. The ring gear R2 can be appropriately coupled to the carrier PC1 via the third clutch C3.

First to third clutches C1, C2 and C3,
The first and second brakes B1 and B2 are actuated by the supply of hydraulic pressure to perform the appropriate coupling and fixing, respectively. However, the power transmission train of FIG. 1 includes the first to third clutches C.
1, C2, C3 and first and second brakes B1, B2
2 are operated in various combinations (shown by circles) as shown in the table of FIG. 2 in combination with the appropriate operation (engagement) of the one-way clutch OWC to constitute the planetary gear sets G1 and G2. Of the input shaft I / S
By changing the rotation speed ratio of the output shaft O / S with respect to the rotation speed of, the forward four speeds and the reverse first speed can be obtained.

The first brake B1 is operated at the first speed when engine braking is required at the first speed. When the first brake B1 is not operated, the one-way clutch OWC receives the reaction force. However, although the first speed is achieved, engine braking is impossible due to the idling of the one-way clutch OWC.

Here, the starting friction element in the present invention is
It is a friction element that is engaged when a select operation is performed from the non-running range to the running range when starting,
As is clear from FIG. 2, when moving forward, the third clutch C3
The first clutch C1 corresponds to this when the vehicle is moving backward.

First to third clutches C as shown in FIG.
In the present embodiment, a shift control device for selecting a predetermined shift speed by executing the operation / non-operation of C1, C2, C3 and the operation / non-operation of the first and second brakes B1, B2 is shown in FIG. And the configuration shown in FIG. Here, in FIG. 3 and FIG. 4, due to space limitations, the hydraulic circuit of the gear shift control device has the oil passage portion A.
It is divided and shown in B, C, and D.

This speed change control device is equipped with an oil pump O / P.
, Pressure regulator valve 1, manual valve 2
A torque converter relief valve 3, a lockup control valve 4, a pilot valve 5, a first shift valve 6, and a second
The shift valve 7, the third clutch control valve 8, the second brake control valve 9, the second clutch control valve 10, the L range pressure reducing valve 11, the line pressure solenoid SOL1, the lockup solenoid SOL2, the third Clutch solenoid SO
L3, a second brake solenoid SOL4, a second clutch solenoid SOL5, and an accumulator ACC, which have first to third clutches C1, C2, C3,
The first and second brakes B1 and B2 and the torque converter T / C are connected as shown in the figure.

The oil pump O / P supplies the discharge oil to the oil passage 10.
1 through port 201 of pressure regulator valve 1
Supply to. Here, the pressure regulator valve 1
The pressure of the hydraulic oil from the oil passage 101 to the port 201 is increased to generate the line pressure P _L. Since the line pressure P _L is fed back to the spool 301 via the oil passage 102, the pressure regulator valve 1 basically adjusts the line pressure P _L to a value corresponding to the spring force of the regulator spring 302.

By the way, the regulator spring 302
Is seated on the plug 303, and the plug 303
Stroke position of the line pressure solenoid SOL1
Via the circuit 103, the solenoid pressure for line pressure control is applied.
Is also supplied from the manual valve 2 via the oil passage 104.
The line pressure P
_LDepending on the operating state via the line pressure solenoid SOL1
It is possible to control it at
Can be set to a special value as required.

The pilot valve 5 extends from the oil passage 101 to the oil passage 1
The line pressure P _L input via 05 is used as a source pressure to reduce to a constant pilot pressure P _p corresponding to the spring force of the spring 311 and output to the oil passage 106.

This pilot pressure P _p passes through the oil passage 108 to the lockup solenoid SOL2, and also to the oil passage 10
To the third clutch solenoid SOL3 via 9,112,
Further, the oil reaches the third brake solenoid SOL4 via the oil passages 109 and 113, reaches the second clutch solenoid SOL5 via the oil passages 109 and 114, and reaches the line pressure solenoid SOL1 via the oil passage 115.

The line pressure solenoid SOL1 reduces the constant pilot pressure P _p input through the oil passage 115 in accordance with the drive duty to generate a solenoid pressure for controlling the line pressure, which is then passed through the oil passage 103. It is supplied to the pressure regulator valve 1 to help control the line pressure P _L. Therefore, by controlling the duty of the line pressure solenoid SOL1, it is possible to generate the line pressure P _L that matches the operating state in the oil passage 101, and to supply this to the input port 210 of the manual valve 2 and also to the accumulator ACC. Supply as pressure.

During the adjustment of the line pressure P _L by the pressure regulator valve 1 described above, the surplus oil discharged from the port 205 flows into the torque converter relief valve 3 via the oil passage 120, and the torque converter relief valve 3 Outputs the inflow oil to the oil passage 122 with a constant hydraulic pressure corresponding to the spring force of the spring 321.

Here, the constant hydraulic pressure to the oil passage 122 is set to a value at which the torque converter T / C is not destroyed, and the torque converter relief valve 3 has a function of preventing the torque converter T / C from being destroyed. . The constant hydraulic pressure to the oil passage 122 thus regulated by the torque converter relief valve 3 is supplied to the lockup control valve 4.

Next, to explain the lockup control system of the torque converter T / C, this lockup control is performed by the lockup solenoid SOL7 via the lockup control valve 4 as follows.

The lockup solenoid SOL2 is described above.
As shown in FIG.
Pilot pressure P_pHas been supplied by this pilot
Pressure P _pIs regulated by the drive duty according to the running condition.
From the oil passage 123 to the end chamber 24 of the lockup control valve 4.
Supply to 0.

When it is determined that the torque converter T / C should be in the lockup state from the running state and a lockup command is issued, the lockup solenoid SOL2
The solenoid pressure from the oil passage 123 to the oil passage 123 is maximized. At this time, the force that biases the valve spool 330 and the plug 332 of the lockup control valve 4 to the left in the figure overcomes the force that biases them to the right, and the spool in the lockup control valve 4 is reversed. The 330 and the plug 332 are shifted leftward in the drawing.

Therefore, the release chamber RE of the torque converter T / C is opened to the atmosphere through the oil passage 127 and the port 244 and the drain port 243 of the lockup control valve 4, and the apply chamber AP of the torque converter T / C is opened.
Port 245 of oil passage 128 and lockup control valve 4
Through to port 242. Therefore, the oil introduced from the torque converter relief valve 3 into the oil passages 122 and 126 passes through the ports 242 and 245 and further into the oil passage 128.
Is supplied to the torque converter apply chamber AP via.

At this time, the torque converter T / C allows the working fluid to flow from the apply chamber AP to the release chamber RE, and the power is transmitted in the lockup state in which the lockup clutch L / C shown in FIG. 1 is engaged. It can be performed.

Next, the torque converter T /
When it is determined that C should be in the converter state and the lockup command is erased, the lockup solenoid SO
Solenoid pressure from L2 to oil passage 123 is minimized.
At this time, the valve spool 33 in the lockup control valve 4
0 and the force that urges the plug 332 to the left in the figure are reduced, and as a result, the force that urges the valve spool 330 and the plug 332 to the right overcomes the force that urges the valve spool 330 and the plug 332 to the left, and The spool 330 and the plug 332 are shifted rightward in the figure. Therefore, the release chamber RE of the torque converter T / C communicates with the oil passages 125 and 124 via the oil passage 127 and the ports 244 and 241.
Further, torque converter apply chamber AP communicates with oil passage 130 via oil passage 128 and ports 245, 246.

At this time, the torque converter T / C allows the working fluid to flow from the release chamber RE to the apply chamber AP, and the power is transmitted in the converter state in which the lockup clutch L / C shown in FIG. 1 is released. It can be carried out.

The manual valve 2 is manually operated by a driver through a shift linkage by a select lever (not shown) in accordance with a desired traveling mode. The selectable traveling modes include a parking (P) range and a backward traveling. The (R) range, the stop (N) range, the forward automatic variable speed travel (D) range, and the first speed engine brake (L) range are set.

Here, although the parking (P) range and the stop (N) range correspond to the non-running range, and the others correspond to the running range, the selection shock mitigation, which is the object of the present invention, is a friction element at the time of starting. In particular, in this specification, the forward automatic shift travel (D) range and the reverse travel (R) range mean the travel range.

On the other hand, the manual valve 2 is, as described above,
Oil passage 101 regulated by pressure regulator valve 1
Line pressure P _L of is introduced into the input port 210,
It is assumed that the line pressure P _L to the input port 210 is selectively guided to the output ports 2D, 2L, 2R according to the selected range, and all the output ports to which the line pressure P _L is not supplied are drained.

In the P and N ranges of the manual valve 2, all the output ports 2D, 2L and 2R are led to the drain, and in the D range, the line pressure P _{L of the} port 210.
Is supplied to the port 2D as D range pressure, in the L-range, supplied as L range pressure line pressure P _L of the port 210 to the port 2D and 2L, the R-range, the port of the line pressure P _L of the port 210 It shall be supplied to 2R as R range pressure.

Here, the manual valve output port 2R is
It is connected to the oil passage 104 from the pressure regulator valve 1 and is connected to the first clutch C1 via the one-way orifice 212 and the accumulator ACC via the oil passages 118 and 119, and is also connected to the first via the oil passage 118 and the shuttle valve 211. Connect to brake B1.

The manual valve output port 2D is connected to the port 281 of the second shift valve 7 via the oil passage 116 and to the port 261 of the first shift valve 6 via the oil passage 132 branched from the oil passage 116. In addition to connecting, oil passage 116
Is connected to the port 401 of the second brake control valve 9 via the oil passages 133 and 134 branched from
It is connected to the port 411 of the second clutch control valve 10 via oil passages 133 and 135 branched from 6.

The manual valve output port 2L is connected to the port 263 of the first shift valve 6 via the oil passage 117.

Next, the first shift valve 6 and the second shift valve 7 will be described. In these shift valves, the D range pressure output from the port 2D in the D range of the manual valve 2 is as follows. Supplied. In other words, the D range pressure is
The port 26 of the first shift valve 6 via the oil passages 116 and 132.
1 and is also introduced into the port 281 of the second shift valve 7 via the oil passage 116. Furthermore, manual valve 2
When the L range pressure is output from the port 2L to the oil passage 117 in the L range, the D range pressure is introduced to the first shift valve 6 and the second shift valve 7 in the same manner as described above. Thus, the L range pressure of the oil passage 117 is additionally introduced into the port 263 of the first shift valve 6.

The first shift valve 6 comprises a spool 350 which is elastically supported by a spring 351 at the position shown in the left half portion, and the second clutch operating pressure is supplied from an oil passage 136 communicating with an operating pressure oil passage 149 of the second clutch C2. Is supplied to the end chamber 264, that is, when the second clutch C2 is actuated, the second clutch operating pressure is assumed to switch the spool 350 to the opposite position in the right half portion against the spring 351.

The second shift valve 7 also includes a spool 360 elastically supported by a spring 361 at the position shown in the left half portion, and an oil passage 137 communicating with an operating pressure oil passage 146 of the second brake B2.
When the second brake operating pressure is supplied from the valve to the end chamber 282, that is, when the second brake B2 is operated, the spool 360 is switched by the second brake operating pressure against the spring 361 to the opposite right half portion illustrated position. Shall be provided.

The first shift valve 6 allows the port 262 to communicate with the port 261 and the port 265 to communicate with the port 263 when the spool 350 is in the position shown in the left half by the spring 351 so that the spool 350 has the end chamber 264. When the second clutch actuating pressure is applied to the port 261 to move to the position shown in the right half portion against the spring 351.
2 is switched and connected to the drain port 266, and the port 265 is switched and connected to the drain port 267.

Further, the second shift valve 7 allows the port 283 to communicate with the port 281 when the spool 360 is in the position shown in the left half portion by the spring 361, and the port 28
4 to the port 285, and the spool 360 is connected to the end chamber 28.
When the second brake actuation pressure to 2 is stroked to the position shown in the right half portion against the spring 361, the port 283 is connected to the port 286 and the port 284 is connected to the drain port 287. To do.

Here, the port 262 of the first shift valve 6
And the port 286 of the second shift valve 7 between the oil passage 13
8 and the port 265 of the first shift valve 6 and the port 285 of the second shift valve 7 are connected by an oil passage 139.

The port 284 of the second shift valve 7 is connected to the input port 25 of the L range pressure reducing valve 11 via the oil passage 140.
Connect to 0. The L range pressure reducing valve 11 inputs the L range pressure output from the port 2L to the oil passage 117 in the L range of the manual valve 2 via the first and second shift valves 6 and 7 and the oil passage 140 as described later. It shall be supplied to the port 250.

Here, the L range pressure reducing valve 11 is the spool 3
40 is urged downward by a spring 341 in the drawing, and when the manual valve 2 is in the L range, the oil passage 1 is fed from the port 2L.
17, first and second shift valves 6, 7 and oil passage 140
L range pressure output through (the same value as line pressure P _L )
Is reduced to a value corresponding to the spring force of the spring 341, is output to the oil passage 130, and is supplied to the first brake B1 via the shuttle valve 211.

The port 283 of the second shift valve 7 is connected to the input port 2 of the third clutch control valve 8 by the oil passage 150.
A check valve 151, which is connected to 91 and allows the oil flow from the second shift valve 7 to the third clutch control valve 8 and blocks the oil flow in the reverse direction, is inserted in the oil passage 150. Stop valve 151
A bypass orifice 152 is provided in parallel with the.

The third clutch control valve 8 controls the input pressure to the port 291 according to the solenoid pressure (electronic control pressure) supplied from the output oil passage 141 of the third clutch solenoid SOL3 to the end chamber 292. A third clutch pressure is output to 293, and a spool 370 that responds to the solenoid pressure in the end chamber 292 is provided, and a spring 371 is applied to the spool 370 in a direction facing the solenoid pressure. Here, the third clutch pressure from the port 293 passes through the oil passage 142 on the one hand, and then the spring 371.
Is fed back to the end chamber 294 in which it is stored, and is supplied to the third clutch C3 via the oil passage 143 on the other hand.

The third clutch solenoid SOL3 uses the pilot pressure P _p from the oil passage 112 as a source pressure and applies the solenoid pressure (electronic control pressure) corresponding to the drive duty (control command) from the oil passage 141 to the third clutch control valve. End chamber 2 of 8
The drive duty is to be arbitrarily determined by a microcomputer according to the traveling state.

The third clutch control valve 8 is stroked against the spring 371 from the position shown in the spool 370 by the increase of the solenoid pressure to the end chamber 292, and the port 293 is stroked.
Is communicated with the port 291 as the solenoid pressure increases, and the third clutch pressure from the port 293 is increased. Since this third clutch pressure is fed back to the end chamber 294, as it rises, the spool 370 is pushed back to cause the port 293 to communicate with the drain port 295, so that the third clutch pressure corresponds to the solenoid pressure to the end chamber 292. The third clutch pressure can be arbitrarily controlled by the drive duty of the third clutch solenoid SOL3 without increasing above the above value.

The second brake control valve 9 controls the input pressure to the port 401 to the second brake to the port 403 according to the solenoid pressure supplied from the output oil passage 144 of the second brake solenoid SOL4 to the end chamber 402. The spool 380, which outputs the pressure, responds to the solenoid pressure in the end chamber 402.
Then, the spring 381 is actuated in the direction opposite to the solenoid pressure. Here, the second brake pressure from the port 403 is fed back to the end chamber 404 in which the spring 381 is accommodated via the oil passage 145 on the one hand, and is supplied to the second brake B2 via the oil passage 146 on the other hand.

The second brake solenoid SOL4 supplies the solenoid pressure corresponding to the drive duty from the oil passage 144 to the end chamber 402 of the second brake control valve 9 using the pilot pressure P _p from the oil passage 113 as the original pressure. Then, the drive duty is arbitrarily determined by the microcomputer according to the traveling state.

The second brake control valve 9 is stroked from the position shown in the drawing against the spring 381 by the rise of the solenoid pressure to the end chamber 402, and the port 403 is moved.
Is communicated with the port 401 as the solenoid pressure increases, and the second brake pressure from the port 403 is increased. Since this second brake pressure is fed back to the end chamber 404, as it rises, the spool 380 is pushed back to cause the port 403 to communicate with the drain port 405, so that the second brake pressure corresponds to the solenoid pressure to the end chamber 402. The second brake pressure can be arbitrarily controlled by the drive duty of the second brake solenoid SOL4 without increasing above the value.

The second clutch control valve 10 extends from the output oil passage 147 of the second clutch solenoid SOL5 to the end chamber 412.
In accordance with the solenoid pressure supplied to the port 411, the input pressure to the port 411 is controlled and output to the port 413 as the second clutch pressure. The spool 390 is provided which responds to the solenoid pressure in the end chamber 412.
Then, the spring 391 is applied in the direction opposite to the solenoid pressure. Here, the second clutch pressure from the port 413 is fed back to the end chamber 414 in which the spring 391 is accommodated via the oil passage 148 on the one hand, and is supplied to the second clutch C2 via the oil passage 149 on the other hand.

The second clutch solenoid SOL5 supplies the solenoid pressure according to the drive duty from the oil passage 147 to the end chamber 412 of the second clutch control valve 10 using the pilot pressure P _p from the oil passage 114 as the original pressure. Then, the drive duty is arbitrarily determined by the microcomputer according to the traveling state.

The second clutch control valve 10 has an end chamber 412.
Due to the increase of the solenoid pressure to the spool 390, the spool 390 is stroked from the illustrated position against the spring 391, and
3 is communicated with the port 411 as the solenoid pressure increases, and the second clutch pressure from the port 413 is increased. This second clutch pressure is fed back to the end chamber 414, so as it rises, the spool 390 increases.
Is pushed back to make the port 413 communicate with the drain port 415, so that the second clutch pressure does not rise above the value corresponding to the solenoid pressure to the end chamber 412, and the second clutch pressure is set to the drive duty of the second clutch solenoid SOL5. Can be arbitrarily controlled by.

The operation of the shift control device according to the above embodiment will be described below. (P, N range) If the driver wants to park or stop,
When the manual valve 2 is set to the P range or the N range, the manual valve 2 does not supply the line pressure P _L of the input port 210 to any of the output ports 2L, 2D, 2R and the output ports 2L, 2D, 2R. Drain all. Therefore, on the hydraulic circuits of FIG. 3 and FIG. 4, all the friction elements C1, C2, C3, B1, B2 whose operating hydraulic pressure is the pressure from the manual valve output ports 2L, 2D, 2R are deactivated. The gear transmission mechanism shown in FIG. 1 is in a neutral state in which power is not transmitted and enables parking or stopping.

(D range) When the driver desires the automatic forward variable speed running and sets the manual valve 2 to the D range, the manual valve 2 sets the line pressure P _L of the input port 210 to the port 2D as the D range pressure. This D range pressure is output and the corresponding ports 261 and 28 of the first and second shift valves 6 and 7 are output.
1 to the second brake control valve 9 and the second
It is supplied to the corresponding ports 401 and 411 of the clutch control valve 10.

When the D range first speed microcomputer determines from driving conditions that the first speed should be selected, the third clutch solenoid SOL3 is turned on, and the second brake solenoid SOL4 and the second clutch solenoid SOL5 are turned off. To do. Second
When the brake solenoid SOL4 is turned off, the end chamber 402 of the second brake control valve 9 is put into a non-pressure state, the second brake control valve 9 is opened, and the port 403 and the drain port 405 are operated.
The state shown in the figure is that there is a gap between them, the operating pressure of the second brake B2 is not generated, and the second brake B2 is released. When the second clutch solenoid SOL5 is turned off,
The end chamber 412 of the clutch control valve 10 is set to a non-pressure state, the second clutch control valve 10 is set to be in the illustrated state in which the port 413 and the drain port 415 are communicated, and the working pressure of the second clutch C2 is not generated. This second clutch C2 is released.

Here, the first shift valve 6 and the second shift valve 7, which respond to the operating pressure of the second clutch C2 and the operating pressure of the second brake B2, respectively, are end chambers 264 and 282.
Since the operating pressure corresponding to is not supplied, the left half portion is in the illustrated position.

As a result, the port 261 of the first shift valve 6
And 262 are in communication with each other, and through the oil passage 132, port 2
The D range pressure introduced into 61 is introduced into the oil passage 138 via the port 262, and further the port 286 of the second shift valve.
Will be introduced to. However, since the second shift valve spool 360 is located at the position shown in the left half portion and blocks the port 286, the D range pressure from the relevant path does not contribute to the gear shift. On the other hand, through the oil passage 116, the second shift valve 7
Since the spool 360 of the second shift valve 7 is located at the position shown in the left half portion and communicates between the ports 281 and 283, the D range pressure introduced into the port 281 of the port 281 of FIG. The oil is introduced into the oil passage 150 via the check valve 151 and further introduced into the input port 291 of the third clutch control valve 8 via the check valve 151.

Here, when the third clutch solenoid SOL3 is turned on, the duty control (electronic control) of the third clutch solenoid SOL3 is appropriately performed so that the third clutch solenoid SOL3, which operates as described above, is operated according to the solenoid pressure output to the oil passage 141. The clutch control valve 8 can arbitrarily and arbitrarily determine the third clutch pressure for engaging the third clutch C3. Under the control of the third clutch pressure, the third clutch C3 is operated at the first speed.
Can be concluded. Then, the second brake B
2 and the second clutch C2 are released as described above, and in the D range, the manual valve output port 2
L range pressure and R from L, 2R to oil passages 117, 118
Since the range pressure is not output, the first clutch C1 and the first brake B1 used as these operating pressure sources are also released.

As described above, when the first speed is selected, only the third clutch C3 of the friction elements is engaged, and the other clutches and brakes are not engaged. Therefore, as is apparent from FIG. 2, the first speed selection state can be obtained as required. The third clutch C3
At the time of selecting operation from the N range, which is a non-running range, to the D range, which is a running range,
Selective shock can be reduced by performing transient control as described below.

In the first speed of the D range, the one-way clutch OWC operates as indicated by a circle in the B1 (OWC) column in FIG. The brake doesn't work.

D-range second speed (1 → 2 upshift) When the microcomputer determines from driving conditions that the second speed should be selected, the second brake solenoid SOL4 is additionally added in the first speed selected state. Turn on. Here, when the second brake solenoid SOL4 is turned on, by appropriately controlling the duty of the second brake solenoid SOL4, the oil passage 144
The second brake control valve 9 that acts as described above in accordance with the solenoid pressure output to the second brake B2 can determine the second brake pressure for engaging the second brake B2 one by one arbitrarily. The second brake B2 can be additionally engaged at the second speed under the control of the brake pressure.

At this time, the second shift valve 7, which responds to the operating pressure of the second brake B2, is supplied with the second brake pressure in the end chamber 282, and therefore switches to the position shown in the right half. Also at this time, the supply of the D range pressure from the oil passage 150 to the third clutch solenoid 8 is performed by the oil passages 116 and 13.
2, through the ports 261 and 262 of the first shift valve 6 and the ports 286 and 283 of the second shift valve 7, so that the third clutch C3 can be continuously engaged. Therefore, the third clutch C3 is engaged and the second brake B2 is engaged, and the other clutches and brakes are not engaged.
As is apparent from the above, the second speed selection state can be obtained as required.

D range 3rd speed (2 → 3 upshift) When the microcomputer judges from driving conditions that the 3rd speed should be selected, the second brake solenoid SOL4 is turned off and at the same time the second clutch is turned on. Solenoid SOL
Turn on 5. Here, the second brake solenoid SOL4
By appropriately controlling the duty of the second brake control valve 9 when it is turned off, the second brake control valve 9 lowers the engagement pressure of the second brake B2 with an arbitrary time-series change according to the solenoid pressure output from the oil passage 144. As a result, the second brake B2 can be released under control during the third speed. Also, the O of the second clutch solenoid SOL5
At the time of N, by appropriately controlling the duty of the second clutch control valve 10 which acts as described above in accordance with the solenoid pressure output to the oil passage 147 from now on.
Can arbitrarily determine the second clutch pressure for engaging the second clutch C2 one by one. Under the control of the second clutch pressure, the second clutch C2 is engaged with the second brake B2 at the third speed. The release can be timed and fastened.

At this time, the second shift valve 7 which responds to the operating pressure of the second brake B2 is not supplied with the second brake pressure in the end chamber 282, and thus returns to the position shown in the left half portion,
Further, the first shift valve 6 that responds to the operating pressure of the second clutch C2 is switched to the position shown in the right half portion because the second clutch pressure is supplied to the end chamber 264, but at this time as well. D from the oil passage 150 to the third clutch solenoid 8
Since the range pressure is continuously supplied through the oil passage 116 and the ports 281 and 283 of the second shift valve 7, the third clutch C3 can be continuously engaged. Therefore, while maintaining the engaged state of the third clutch C3, the second brake B2 is released and, at the same time, the second clutch C2 is engaged. Obtainable.

D range 4th speed (3 → 4 upshift) When the microcomputer judges from driving conditions that the 4th speed should be selected, the second clutch solenoid SOL5 is held in the ON state to cause the second clutch C2 to operate. While the engagement is maintained, the second brake solenoid SOL4 is turned on again under the duty control, and at the same time, the third clutch solenoid SOL3 that was turned on at the first speed to the third speed is turned off.
F Second by turning on the second brake solenoid SOL4
The brake control valve 9 can increase the engagement pressure of the second brake B2 and engage it. When the third clutch solenoid SOL3 is OFF, the third clutch control valve 8 is
The engagement pressure of the third clutch C3 can be reduced and released. Therefore, it is possible to obtain the fourth speed selection state by switching control in which the third clutch C3 is released and at the same time the second brake B2 is engaged while maintaining the engagement of the second clutch C2.

(L range) When the driver desires engine braking running at the first speed and sets the manual valve 2 to the L range, the manual valve 2 causes the line pressure P to the port 210 to reach P.
_L, and the addition to also output to the port 2D as in the D range, the line pressure port 210 to port 2L P _L
Is output as L range pressure. The L range pressure output from the port 2L is supplied from the oil passage 117 to the port 263 of the first shift valve 6.

In the L range, the microcomputer turns on the third clutch solenoid SOL3 to turn on the third clutch C3, as in the case of the first speed in the D range.
The second brake solenoid SOL4 and the second brake solenoid SOL4.
The clutch solenoid SOL5 is turned off to release the second brake B2 and the second clutch C2. As a result, the gear transmission mechanism of FIG. 1 is in the first speed selection state.

On the other hand, the first shift valve 6 and the second shift valve 7 which respond to the working pressure of the second clutch C2 and the working pressure of the second brake B2 are not supplied with the working pressures corresponding to the end chambers 264 and 282, respectively. As a result, the left half portion is in the illustrated position. As a result, the port 26 of the first shift valve 6 is
3, 265 communicate with each other, and the port 28 of the second shift valve
5,284 communicate with each other. Therefore, the oil passage 117
The L range pressure introduced into the port 263 via the port 263 is introduced into the oil passage 139 via the port 265 of the first shift valve 6, and further passes through the ports 285 and 284 of the second shift valve and the oil passage 140 in order to the L range. Reach the range pressure reducing valve 11.

Here, the L-range pressure reducing valve 11 reduces the input L-range pressure to a constant pressure by the above-mentioned action, supplies this to the first brake B1 via the shuttle valve 211, and the first brake B1 is supplied. The fastening operation can be performed.

Therefore, in the L range, the D range first
Similar to the case of the speed, the first brake B1 is engaged in addition to the engagement operation of the third clutch C3, which enables the engine brake traveling at the first speed.

(R range) When the driver desires backward running and sets the manual valve 2 to the R range, the manual valve 2 outputs the line pressure P _L to the port 210 to only the port 2R as the R range pressure, Drain all other output ports 2D and 2L. The R range pressure from the port 2R reaches the first brake B1 via the oil passage 118 and the shuttle valve 211 on the one hand to engage the same, and on the other hand, the oil passage 11
It is supplied to the first clutch C1 via 8, 119, the one-way orifice 212, and the accumulator ACC, and engages the first clutch C1.

By engaging the first clutch C1 and the first brake B1 in this manner, the gear transmission mechanism of FIG. 1 can be brought into the reverse shift speed selection state as required as is apparent from FIG.

The above-mentioned line pressure control and lock-up control and the above-mentioned shift control are respectively the transmission controller 500 of FIG.
Line pressure solenoid SOL1, lockup solenoid SOL2, third clutch solenoid SOL
3, by achieving duty control of the second brake solenoid SOL4 and the second clutch solenoid SOL5,
Therefore, the controller 500 has a signal from the inhibitor switch 501 that detects the current selection range of the manual valve 2 and an engine rotation sensor 502 that detects the engine speed N _e in the preceding stage of the automatic transmission.
Signal from vehicle and vehicle speed sensor 503 for detecting vehicle speed VSP
From the throttle opening sensor 504 for detecting the engine throttle opening TVO, and a signal from the oil temperature sensor 505 for detecting the transmission operating oil temperature T.

Then, the controller 500 executes the control program of FIG. 6 to perform the select shock mitigating function aimed at by the present invention during the above-described shift control, particularly during the select operation from the N range to the D range. .

In FIG. 6, first in step 511,
It is determined whether or not there is a select operation from the N range to the D range, and step 5 is performed until the select operation is performed.
The determination of 11 is repeated. When the selection operation from the N range to the D range is performed, in step 512, the engine speed N _e is read and the transmission operating oil temperature T
Then, in step 513, the map corresponding to FIG. 7 is searched for the control command delay time Δt ₁ based on the engine speed _Ne and the transmission operating oil temperature T.

Here, the control command delay time Δt ₁ is N → D
Corresponding to the time from the instant of selection until the drop of the line pressure P _L caused by the selection operation as described above subsides, and during this time, the first to be engaged during the selection operation from the N range to the D range. This is for delaying the output of the operating pressure control command related to the 3-clutch C3 (starting friction element).

By the way, as is apparent from FIG. 7, the control command delay time Δt ₁ becomes longer as the engine speed N _e becomes lower, and becomes longer as the transmission operating oil temperature T becomes higher. Derives from That is, the transmission operating oil, which is the pressure medium of the line pressure P _L , is discharged from the oil pump driven by the engine. The lower the engine speed N _e, the line pressure caused by the N → D select operation. This is because the convergence time of the decrease becomes long. Also,
This is because the higher the transmission hydraulic oil temperature T, the lower the viscosity of the transmission hydraulic oil, and the lower the viscosity, the longer the convergence time of the line pressure reduction due to the N → D select operation.

In the next step 514, the flag FLAG is set to 1 so as to indicate that it is the first control after the N → D select operation, and the next step 515 controls the control to steps 516 and 517. To proceed. In step 516, the timer t is reset to 0 so that the elapsed time from the N → D select operation can be measured, and in step 517, the above flag FLAG is reset to 0 and step 515 controls the control after the second time. 5
Try to proceed to 18.

In step 518, the timer t is incremented by the calculation cycle Δt to measure the elapsed time from the N → D select operation. In step 519, the timer t sets the control command delay time set in step 513. Δ
Until it is determined that t ₁ is exceeded, in step 520,
The third clutch operating pressure control command S _c (see also FIG. 5) to the third clutch solenoid SOL3 is maintained at 0, and the control is returned to step 515. That is, the output of the operating pressure control command S _c of the third clutch C3 that should be engaged with the N → D select operation is prohibited until the control command delay time Δt ₁ elapses from the N → D select operation. During this period, the start of the engagement control of the third clutch C3 is delayed.

When it is determined in step 519 that the timer t has exceeded the control command delay time Δt ₁ set in step 513, in step 521, the operating pressure control command S _c for the third clutch C3 is controlled as well known in the art. Then N →
The third clutch C to be engaged with the D select operation
By gradually advancing the engagement of No. 3 so as not to cause a select shock, the automatic transmission is brought from the neutral state to the first speed selected state.

Measures for reducing the above select shock have been taken.
The engagement control of the third clutch C3 is based on the time chart.
As shown in Fig. 8, the N → D select operation
Time t ₁To control command delay time Δt₁Than the moment when
Operating pressure control command S for the third clutch C3_cStart control
Then, the operating pressure P of the third clutch C3_cIs shown in the figure.
To raise select shock gradually
It

Therefore, when the N → D select operation is performed, the line pressure P _L temporarily drops as shown by α in FIG. 8, and the pilot pressure P _p cannot be set to the specified value corresponding to the above constant pressure. Even though the target value is decreased and the desired control cannot be performed, the operating pressure control command _Sc
11 is avoided, and the problem described above with reference to FIG. 11, that is, the problem that not only the desired select shock mitigation effect is not obtained but also the select shock becomes larger than when no shock countermeasure is taken is avoided. can do.

Thus, in this embodiment, N → D
By the well-known third clutch operating pressure control command S _c after the instant when the control command delay time Δt ₁ has elapsed from the select operation instant t _1, the change tendency of the engine speed N _e and the transmission output torque T _o shown in FIG. 8 are shown. As is clear from the waveform of, the engagement shock of the third clutch C3, that is, the N → D select shock can be reduced as desired.

Although the third clutch operating pressure control command S _c is well known as a measure against select shock,
For example, the following can be used. That is,
From the instant when the control command delay time Δt ₁ elapses, a predetermined time Δt _p
During the time, the operating pressure control command S _c of the third clutch C3 is set to a high value for precharging, and then gradually increased from the instant t ₂ after maintaining the command value of the return spring equivalent pressure, The operating pressure P _c of the three-clutch C3 is gradually increased as shown in the figure, whereby the engagement of the third clutch C3 is gradually advanced, and the select shock accompanying the engagement of the third clutch C3 is reduced.

9 and 10 show another embodiment of the present invention.
The select shock reducing device which becomes a form is shown,
In the form, as shown by the chain double-dashed line in FIG.
Hydraulic switch 50 corresponding to the pressure drop detecting means in
The signal from 6 is input to the controller 500. here
The hydraulic switch 506 controls the line pressure P._LOr Pyro
Pressure P_pIn response to the set pressures illustrated in FIG.
P_SIf it is above, it is turned on and the set pressure P _SIf less than
It shall be turned off. And set pressure P_SThe Pyro
Pressure P _pIt is decided to be a value slightly lower than the specified value of
The pilot pressure P in any case_pTo a specified value
Conditions.

Then, the third clutch engagement control program to be executed when N → D is selected is changed from that shown in FIG. 6 to that shown in FIG. That is, steps 512 and 513 in FIG. 6 are deleted, and when the N → D select operation is detected in step 511, it is indicated in step 514 that it is the first control after the N → D select operation. , Flag FLAG is set to 1 and the next step 515 advances control to steps 516 and 517.

At step 516, the timer t is reset to 0 so that the elapsed time from the N → D select operation can be measured, and at step 517, the above flag FLAG is set.
Is reset to 0, and the control is advanced to step 518 after the second time in step 515, and in step 518, the timer t is incremented by the calculation cycle Δt and N → D.
Measure the elapsed time from the select operation.

Further, in the present embodiment, step 519 in FIG. 6 is replaced with steps 531 to 533. In step 531, the timer t incremented in step 518 is set to the set time Δt ₀ shown in FIG.
Until it is determined that the value exceeds the
The third clutch operating pressure control command S _c to the clutch solenoid SOL3 is maintained at 0 and the control is returned to step 515.

Here, the set time Δt ₀ is, for example, as shown in FIG.
As shown in 0, the time from the N → D select operation to the period during which the line pressure drop occurs due to the operation is set, and the operating pressure of the third clutch C3 to be engaged with the N → D select operation. The output of the control command S _c is unconditionally prohibited until the set time Δt ₀ elapses from the N → D select operation, and the engagement start of the third clutch C3 is unconditionally delayed at least during this period.

When it is determined in step 531 that the timer t has exceeded the set time Δt ₀ , in step 532,
As long as the hydraulic switch 506 is confirmed to be ON and OFF and it is determined in step 533 that the hydraulic switch 506 is OFF, that is, it is determined that the pilot pressure P _p or the line pressure P _L is less than the set pressure P _S. As far as possible, the output of the third clutch operating pressure control command S _c is continuously prohibited by step 520, and the engagement start of the third clutch C3 is continuously delayed.

When it is determined in step 533 that the hydraulic switch 506 is ON, that is, when the pilot pressure P _p or the line pressure P _L is equal to or higher than the set pressure P _S , in step 521, the third clutch The operating pressure control command S _c is controlled to increase as is well known, and the engagement of the third clutch C3, which should be engaged in response to the N → D select operation, is gradually advanced so that a select shock does not occur, and the automatic transmission From the neutral state to the first speed selection state.

The engagement control of the third clutch C3 having the countermeasure against select shock according to the present embodiment is shown in a time chart as shown in FIG.
From the selection operation instant t ₁ to the set time Δt ₀ ,
The output of the clutch operating pressure control command S _c is unconditionally prohibited to delay the start of engagement of the third clutch C3. Then, the hydraulic switch 506 is turned off at the instant when the set time Δt ₀ has elapsed.
If, that is, if the pilot pressure P _p cannot reach the specified value, the third clutch operating pressure control command S
The output of _c is continuously prohibited, and the engagement start of the third clutch C3 is continuously delayed.

After that, when the hydraulic switch 506 is turned on, that is, when the pressure drop state at the time of N → D selection converges and the pilot pressure P _p can be brought to a substantially specified value, the third clutch operating pressure is reached. The control command S _c is started to be increased, and the operating pressure P _c of the third clutch C3 is gradually increased as shown in FIG.

Therefore, during the N → D select operation, the line pressure P _L temporarily drops as shown by α in FIG. 10, and the pilot pressure P _p cannot be set to the specified value corresponding to the above constant pressure. Even though the target value is decreased and the desired control is not performed, the operating pressure control command S
It does not output _c , and the problem described above with reference to FIG. 11, that is, not only the desired select shock mitigation effect is not obtained, but also the select shock becomes larger than when no shock countermeasure is taken Can be avoided.

As described above, in the present embodiment, it is possible to achieve the same operational effects as in the above-described embodiments, but in addition to that, the following operational effects can be achieved. In other words, the engagement control start of the third clutch is delayed as long as the pressure drop is detected by the hydraulic switch 506, so that the action and effect in the above-described embodiment can be made more reliable, and further, from the select operation, In the case where there is a time delay before the pressure drop of, the problem that the start of the engagement control of the third clutch is not delayed during this time delay can be solved.

In any of the above embodiments, N → D
Although the measure for reducing the select shock at the time of select has been described, the measure for reducing the select shock at the time of selecting N → R is performed by controlling the engagement of the first clutch C1 that should be engaged in the reverse (R) range in the same manner as above. It goes without saying that it can be realized.

[Brief description of drawings]

FIG. 1 is a skeleton diagram showing a power transmission train of an automatic transmission equipped with a select shock reducing device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a relationship between an engagement logic table of various friction elements in the power transmission train shown in FIG. 1 and a selected shift speed.

3 is a hydraulic circuit diagram showing a part of a shift control hydraulic circuit applied to the power transmission train shown in FIG.

FIG. 4 is a hydraulic circuit diagram showing the rest of the shift control hydraulic circuit.

FIG. 5 is a block diagram showing an electronic control system for duty-controlling a solenoid in the shift control hydraulic circuit.

FIG. 6 is a flow chart showing a third shock select shock reducing engagement control program executed by the electronic control system.

FIG. 7 is a diagram showing a change characteristic relating to a delay time of a third clutch operating pressure control command.

FIG. 8 is a time chart showing engagement control for reducing the select shock of the third clutch.

FIG. 9 is a flowchart showing a third shock select shock reducing engagement control program for another embodiment of the present invention.

FIG. 10 is a time chart showing engagement control for reducing the select shock of the third clutch.

FIG. 11 is a time chart showing select shock reducing engagement control of a starting friction element by a conventional select shock reducing device.

[Explanation of symbols]

T / C Torque converter I / S Input shaft O / S Output shaft G1 1st planetary gear set G2 2nd planetary gear set C1 1st clutch (starting friction element) C2 2nd clutch C3 3rd clutch (starting friction element ) B1 1st brake B2 2nd brake OWC One-way clutch 1 Pressure regulator valve 2 Manual valve 3 Torque converter relief valve 4 Lockup control valve 5 Pilot valve 6 1st shift valve 7 2nd shift valve 8 3rd clutch control valve 9th 2 Brake control valve 10 Second clutch control valve 11 L range pressure reducing valve SOL1 Line pressure solenoid SOL2 Lock up solenoid SOL3 Third clutch solenoid SOL4 Second brake solenoid SOL5 Second clutch solenoid ACC Accumulator 500 Transmission controller 501 Inhibitor switch 502 Engine rotation Sensor 503 Vehicle speed sensor 504 Throttle opening sensor 505 Oil temperature sensor 506 Hydraulic pressure Switch (pressure drop detecting means) P _L line pressure P _p pilot pressure

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-98057 (JP, A) JP-A-6-159494 (JP, A) JP-A 64-12163 (JP, A) JP-A 61- 13053 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (5)

(57) [Claims] 1. A plurality of friction elements are selectively engaged by a fluid pressure in a travel range to determine a selected gear stage of a speed change gear mechanism, and should be engaged during a select operation from a non-travel range to a travel range. In an automatic transmission configured to reduce select shock by gradually increasing the fluid pressure of the starting friction element by an electronically controlled pressure whose line pressure is the original pressure, the fluid pressure of the starting friction element is gradually increased. predetermined time control command of the electronic control pressure to increase, from the select operation instantaneously
Only configured to start outputting the delayed, the predetermined time for the delay, in the previous stage of the automatic transmission
Depending on the engine speed, the lower the engine speed, the longer
Select shock reduction device for automatic transmission characterized by combing . 2. The select shock reducing device for an automatic transmission according to claim 1 , wherein the predetermined time is set to be longer as the temperature is higher in accordance with the hydraulic oil temperature of the automatic transmission. 3. The select operation according to claim 1, wherein the line pressure is reduced during the select operation, or the pilot pressure is created so as to be a constant pressure from the line pressure and used as a source pressure of the electronic control pressure. A select shock reducing device for an automatic transmission, characterized in that a pressure drop detecting means for detecting a decrease in time is provided, and the control command is delayed while the pressure drop is detected by the means. 4. The automatic shift according to claim 3 , wherein the pressure drop detecting means is configured to determine a pressure drop when the pilot pressure does not reach a specified value corresponding to the constant pressure. Select shock reducer for machine. 5. A method according to claim 3 or 4, until the set time from the selecting operation instantaneously has elapsed, configured without the pressure drop detecting means detects the pressure drop performs a delay of the control command Select shock reduction device for automatic transmission characterized by