JPH03199763A - Controller for automatic transmission - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a shock at the time of shift to the D or R range from N, by setting the conclusion condition of each friction conclusion element within a predetermined period so that predetermined speed shift steps may be attained, and at the same time opening the bypass passage of a throttle element. CONSTITUTION:At the time of the N-D or N-R operation, a control means, during a predetermined period, conducts the changeover of a shift valve 63 so that predetermined speed shift steps of more than 2 speeds may be attained, and at the same time conducts control so that an opening/closing means 103 provided at a bypass passage 153 may be opened. Accordingly, oil pressure is speedily supplied without passing a throttle element (one way orifice) 73 at an oil pressure supply passage 120 to a servo piston 45' which is a friction conclusion element concluded at a predetermined speed shift step, and conclusion is made before or at least at the same time with the conclusion of friction conclusion elements which are concluded at all forward speed steps, and going by way of speed shift steps of more than two speeds is surely made, and next, changeover to one speed or a backward speed is made. Thus, the occurrence of a speed shift shock can be restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a control device for an automatic transmission, and particularly to a control device for an automatic transmission. The present invention relates to a control device for an automatic transmission that switches to reverse speed.

(Prior Art) Automatic transmissions generally installed in automobiles combine a torque converter, a speed change gear mechanism, and a plurality of friction engagement elements that switch the power transmission path of the speed change gear mechanism, and these friction engagement elements are It is configured to switch to a predetermined gear by automatically engaging it depending on the driving condition or selectively depending on the range switching by the driver's manual operation, such as N range when starting. When operating from to D range, a predetermined friction engagement element is engaged from a neutral state in which all friction engagement elements are disconnected, and the gear stage is switched to first speed.

By the way, during this N-D operation, when the predetermined frictional engagement element is engaged as described above and the gear stage is switched to 1st gear, the output torque of the engine is at a large ratio corresponding to the reduction ratio of 1st gear. Since the shock is increased and transmitted to the wheels, a so-called ND shock occurs, which causes discomfort to the occupants.

To solve this problem, for example, as disclosed in Japanese Patent Application Laid-Open No. 61-65949, when the N-D operation is performed, the driver does not switch directly from the neutral state to 1st gear, but via a predetermined high gear. The idea is to switch to 1st speed. In other words, since the output torque of the transmission is relatively small at a high gear stage with a small reduction ratio, the shock when this torque is transmitted to the wheels is reduced. Thereafter, the high gear is switched to first gear, which allows the vehicle to start.

(Problem to be Solved by the Invention) By the way, in high gears such as 2nd gear or higher, there is generally a friction engagement element that is always engaged in all forward gears from 1st gear to the highest gear, and a friction engagement element that is always engaged in all forward gears from 1st gear to the highest gear. At least two of the frictional engagement elements are engaged at each gear, so if a high gear is used during the ND operation as described above, at least two frictional engagement elements are engaged from the neutral state. It will be concluded at the same time. However, in this case, the timing of introducing hydraulic pressure to each actuator may be slightly shifted depending on the length of the hydraulic pressure supply passage to the actuator of these frictional engagement elements, the presence or absence of an orifice or an accumulator in each passage, etc. Due to this timing shift, among the frictional engagement elements that are engaged in the advanced gear, especially the frictional engagement elements that are engaged in all forward gears including 1st gear, the friction engagement elements that are engaged in the other gears that are engaged in the advanced gear are If the friction engagement element is engaged before the friction engagement element is engaged, the gear position remains at 1st speed until the latter friction engagement element is engaged. In other words, even if it is controlled to go through a high gear during N-D operation, it actually switches from the neutral state to 1st gear, and then goes through a predetermined high gear and then goes through 1st gear again.
1 speed directly from the neutral state.
This means that the ND shock caused by switching to high speed is not substantially eliminated.

Therefore, the present invention ensures that a high gear is used during the N-D operation or the N-R operation that generates a shock similar to the N-D operation, thereby ensuring that a shock occurs during these operations. The challenge is to prevent this from happening.

(Means for Solving the Problems) In order to solve the above problems, the present invention is characterized by the following precepts.

That is, the automatic transmission control device according to the present invention includes a speed change gear mechanism, a plurality of friction engagement elements that switch the power transmission path of the speed change gear mechanism, and a hydraulic control circuit that selectively engages these friction engagement elements. In the automatic transmission, the hydraulic control circuit includes a throttle element that throttles a hydraulic pressure supply passage to a friction engagement element that is engaged at a predetermined gear position of second speed or higher, a bypass passage that bypasses the throttle element, and a bypass passage that bypasses the throttle element. an opening/closing means for opening and closing the bypass passage, and at the time of a shift operation from the N range to the D range or the R range, the engagement state of each friction engagement element is set so that the above-mentioned predetermined gear stage is distantly related for a predetermined period of time. In addition to setting, for this predetermined period,
The present invention is characterized by comprising a control means for driving the opening/closing means to open the bypass passage. Note that, if the hydraulic control circuit is already provided with the above-mentioned throttle element, bypass passage, and opening/closing means as a countermeasure against shocks during normal gear shifting operations, these can be used as they are.

(Function) According to the above configuration, during N-D or N-R operation,
For a predetermined period of time, a friction engagement element that is engaged at the full forward gear stage and a friction engagement element that is engaged at the predetermined gear stage are connected so that the predetermined gear stages of second speed or higher are distantly related. The control means operates so that the bypass passage is fastened, and at this time, the control means controls the opening/closing means provided in the bypass passage to open. Therefore, hydraulic pressure is quickly supplied to the frictional engagement element that is engaged at a predetermined gear stage through the bypass passage without passing through the throttle element provided in the hydraulic pressure supply passage to the element. , the frictional engagement element is engaged before, or at least simultaneously with, the frictional engagement element that is engaged at the full forward gear stage.

Therefore, when switching from N range to D range or R range, the gears are reliably passed through 2nd gear or higher, and then,
It will switch to 1st speed or reverse speed.

(Example) Examples of the present invention will be described below.

First, the mechanical configuration of the automatic transmission according to this embodiment will be explained with reference to FIG. It has a mechanism 30, a plurality of frictional engagement elements 41 to 46 such as clutches and brakes, and one-way clutches 51 and 52 that switch the power transmission path of the mechanism 30, and these act as a driving range. Each of the H ranges, 1st to 4th speeds in the D range, 1st to 3rd speeds in the 2nd range, and 1st to 2nd speeds in the lunge are available.

The torque converter 20 includes a pump 22 fixedly installed in a case 21 connected to the engine output shaft 1, and a turbine 23 disposed opposite to the pump 22 and driven by the pump 22 via hydraulic oil. , a stator 25 that is interposed between the pump 22 and the turbine 23 and supported by the transmission case 11 via the one-way clutch 24 to increase torque; and the case 21 and the turbine 2
3, and a lock-up clutch 26 that directly connects the engine output shaft 1 and the turbine 23 via the case 21. Then, the turbine 23
The rotation is outputted to the speed change gear mechanism 30 side via the turbine shaft 27. Here, a pump shaft 12 passing through a turbine shaft 27 is connected to the engine output shaft 1, and the shaft 12 drives an oil pump 13 provided at the rear end of the transmission.

On the other hand, the speed change gear mechanism 30 is composed of a Ravigneau-type planetary gear device, and includes a small sun gear 31 with a small diameter loosely fitted on the turbine jab 27, and the sun gear 3.
1, a large diameter large sun gear 32 loosely fitted on the turbine shaft 27, a plurality of short pinion gears 33 meshed with the small sun gear 31, and a front half meshed with the short pinion gear 33. It is composed of a long pinion gear 34 whose rear half meshes with the large sun gear 32, a carrier 35 that rotatably supports the long pinion gear 34 and the short pinion gear 33, and a ring gear 36 which meshes with the front half of the long pinion gear 34. has been done.

A forward clutch 41 and a first one-way clutch 51 are interposed in series between the turbine shaft 27 and the small sun gear 31, and a coast clutch 42 is interposed in parallel with these clutches 41 and 51. In addition, the turbine shaft 27 and carrier 35
A 3-4 clutch 43 is interposed between the turbine shaft 27 and the large sun gear 32, and a reverse clutch 44 is interposed between the turbine shaft 27 and the large sun gear 32. Further, between the large sun gear 32 and the reverse clutch 44, a 2-4 band brake for fixing the large sun gear 32 is provided.
A brake 45 is provided, and the carrier 3
5 and the transmission case 11, a second one-way clutch 52 that receives and stops the reaction force of the carrier 35, and a low reverse brake 46 that fixes the carrier 35 are provided in parallel. The ring gear 36 is connected to the output gear 14, and rotation is transmitted from the output gear 14 to left and right wheels (not shown) via a differential gear.

Here, the frictional engagement elements 4 such as the above-mentioned clutches and brakes, etc.
Table 1 summarizes the relationship between the operating states of clutches 1 to 46 and one-way clutches 51 and 52 and the gear positions.

Margins below Next, a hydraulic control circuit for supplying and discharging hydraulic pressure to and from the actuators of each of the frictional engagement elements 41 to 46 will be described with reference to FIG. Here, among the above actuators,
The hydraulic actuator 45'' of the 2-4 brake 45 is composed of a servo piston having an apply boat 45a and a release boat 45b', and engages the 2-4 brake 45 when hydraulic pressure is supplied only to the apply boat 45a'. , the 2-4 brake 45 is released when hydraulic pressure is not supplied to both boats 45a' and 45b', and when hydraulic pressure is supplied to both boats 45a45b'. Fastening element 41~
The actuator 44.46 consists of a conventional hydraulic piston, which engages the frictional engagement element when hydraulic pressure is supplied.

This hydraulic control circuit 60 includes, as main components, a regulator valve 61 that adjusts the pressure of hydraulic oil discharged from the oil pump 13 to the main line 110 to a predetermined line pressure, and a range control circuit that can be operated manually. a manual valve 62 that selects a gear, and each shift valve 63 of 1-2.2-3.3-4 that operates according to the gear stage to supply and discharge hydraulic pressure to each friction engagement element (actuator) 41 to 46. .64.65 are provided.

The manual valve 62 has an input boat e into which line pressure is introduced from the main line 110, and first to fourth output boats a%d, and by movement of the spool 62a, the input boat e is switched to the D range. and 1st in range 2. It is connected to the second output boat ab, to the first to fourth output boats a and c in the lunge, and to the fourth output boat d in the R range. Each output boat a to d has first to fourth output lines 11, respectively.
1 to 114 are connected.

Also, 1-2.2-3 above. :3-4 shift valve 63
, 64.65 are the spools 63a, 64a, 6, respectively.
5a is biased toward the right side in the drawing by a spring (not shown), and pilot bows 63b, 64b, and 65b are provided on the right side of these spools. A first pilot line 115 led from the main line 110 is connected to the pilot boat 63b of the 1-2 shift valve 63 for the 2-3, 3-4 shift valve 64.
65 pilot boats 64b and 65b have the above-mentioned first
The second. Third pilot lines 117 and 118 are connected to each other, and these pilot lines 11
5,117.118 each have 1. Second. A third solenoid valve 66,67,68 is provided.

These solenoid valves 66 to 68 are respectively ON.
When the pilot line 115, 117.11
8 and drain each corresponding shift valve 63-65.
By discharging the pilot pressure in the pilot boats 63b to 65b, the spools 63a to 65a are positioned on the right side in the drawing, and when the pilot boats 63b to 65b are OFF, the pilot lines 115, 1 are connected to the pilot boats 63b to 65b.
Pilot pressure is introduced from 17 and 118 to position the suburs 63a to 65a on the left side.

Then, these solenoid valves 66 to 68 are turned on,
Each frictional engagement element 41 is moved by the movement of the spools 63a to 65a of each shift valve 63 to 65 due to the OFF operation.
By switching the oil passages leading to the actuators 41 to 46, these frictional engagement elements 41 to 46 are engaged in the combinations shown in Table 1 for each gear stage.

In that case, each gear stage and each solenoid valve 66
The relationship with the ON and OFF combination patterns of ~68 is the second
The settings are as shown in the table.

The following is a blank space, and the first to fourth output lines 111 to 11 connected to each output boat a to d in the manual valve 62 are shown below.
4, main line 1 in each forward range of D, 2.1
The first output line 111 connected to the first output line 110 is branched from the line 116, and this line 116 is used as a forward clutch line and is led to the forward clutch 41 via the one-way orifice 71. Therefore,
D.2. During lunge, the forward clutch 41 is always engaged. Here, an N-D accumulator 72 for buffering when the forward clutch is engaged is connected to the forward clutch line 116 via a line 119.

Further, the first output line 111 is guided to the 1-2 shift valve 63, and when the first solenoid valve 66 is turned on and the spool 63a is positioned to the right, it communicates with the servo apply line 120, and is connected to the one-way orifice 73.
Apply boat 45a of servo piston 45' via
Reach ゛.

Therefore, D.2. When the first solenoid valve 66 is ON in lunge, that is, in 2nd and 3rd gears in D range, 2nd and 3rd gears in 2nd range, and in 2nd gear in lunge, hydraulic pressure (servo apply pressure) is applied to the apply boat 45a. > is introduced, and the 2-4 brake 45 is engaged when hydraulic pressure (servo release pressure) is not introduced to the release port 45b'.The servo apply line 120 also has a line that indicates when the 2-4 brake is engaged. A 1-2 buffering accumulator 74 is connected.

Further, the second output line 112 communicating with the main line 110 in the D and 2 ranges is led to a 2-3 shift valve 64. Then, when the second solenoid valve 67 is OFF and the spool 64a is located on the left side, the line 112 is connected to 3-4 through the one-way orifice 75.
It communicates with the clutch line 121. This line 121 further passes through the one-way orifice 76 to the 3-
4 clutch 43 is reached. Therefore, when the second solenoid valve 67 is OFF in the D, 2 range, that is, in the D range, the 3
, 4th speed, and 3rd speed of the 2nd range, the 3-4 clutch 43 is engaged.

Here, the above-mentioned 3-4 clutch line 121 is connected to the first clutch line 121.
The second drain lines 122 and 123 are branched, and among these, the first drain line 122 is led to the 3-4 shift HAL PRO 5, and when the third solenoid valve 68 is OFF (the spool 65a is on the left side), the first drain line 122 is 124 and to the drain boat of the 2-3 shift valve 64.The second drain line 123 also connects to the one-way orifice 77, the fixed orifice 78, and the one-way orifice 7.
9 to the 3-4 shift valve 65, and when the third solenoid valve 68 is ON (the spool 65a is on the right side), it communicates with the above line 124 and leads to the drain boat of the 2-3 shift valve 64. .Through these, 3
-2.4-2 3-4 clutch 43 when downshifting
However, hydraulic pressure (3-4 clutch pressure) is discharged. Furthermore, between the one-way orifice 77 of the second drain line 123 and the fixed orifice 78, there is a 2-way valve for buffering when the 3-4 clutch is activated. Three accumulators 80 are connected.

Also, a second drain line connected to the first drain line 122 is connected to the first drain line 122.
When the solenoid valve 67 is OFF and the spool 64a of the 2-3 shift valve 64 is located on the left side, the line 125 that communicates with the second output line 112 is led to the 3-4 shift valve 65, and the spool 64a of the 2-3 shift valve 64 is located on the left side. 68 is OF
When the spool 65a is located on the left side at F, it communicates with the servo release line 126. This line 126 leads to the release port 45b' of the servo piston 45' via a one-way orifice 81.82. Therefore, D,
2nd range in 2 ranges. When the third solenoid valves 67 and 68 are both OFF, that is, 3rd gear in D range and 3rd gear in 2nd range.
release port 45b' of servo piston 45a.
A servo release pressure is introduced to release the 2-4 brake 45.

Furthermore, a line 1 branched from between the two one-way orifices 81 and 82 of the servo release line 126
27 communicates with the coast clutch line 128 via the coast control valve 83, one-way orifice 84, and ball valve 85, and reaches the coast clutch 42.

Therefore, the coast clutch 42 is engaged in the 3rd speed of the D range and the 3rd speed of the 2nd range where hydraulic pressure is introduced into the servo release line 126. On the other hand, when the third solenoid valve 68 is OFF, the spool 6 of the 3-4 shift valve 65
5a is located on the left side, and when the second solenoid valve 67 is ON and the spool 64a of the 2-3 shift valve 64 is located on the right side, the forward clutch line 11
6 is the branch line 129.3-4 shift valve 65
, line 130 and 2-3 shift valve 64 to line 131 . This line 131 communicates with the coast clutch line 128 via the ball valve 85, and therefore, the coast clutch 42 operates when the second solenoid valve 67 is ON and the third solenoid valve 68 is OFF.
It is also engaged when in FF, that is, in 2nd gear of 2nd range and 1st and 2nd gear of lunge.

Further, the third output line 113, which is connected to the main line 110 by the manual valve 62, is connected to the low reducing valve 86 as a pressure reducing valve and the line 1.
32 to the 1-2 shift valve 63.

This line 132 is connected to the first solenoid valve 6
6 is OFF and the spool 63a is located on the left side,
It communicates with the low reverse brake line 133 via the one-way orifice 87 and the ball valve 88, and reaches the low reverse brake 46. Therefore, when the first solenoid valve 66 is OFF in the ■ range, that is, in the first lunge gear, the low reverse brake 46 is engaged.

Furthermore, a fourth line that communicates with the main line 110 in the R range
The output line 114 is connected to the low reverse brake line 1 via a line 134 branched from the line 114, the one-way orifice 89, and the ball valve 88.
33, and becomes a reverse clutch line 135, which leads to the reverse clutch 44 via a one-way orifice 90. Therefore, in the R range, the low reverse brake 46 and reverse clutch 44 are always engaged. Here, an N-R accumulator 91 for M impact when the reverse clutch is engaged is connected to the reverse clutch line 135.

The hydraulic control circuit 6o is also provided with a lock-up valve 92 for operating the lock-up clutch 26 in the torque converter 20 shown in FIG.

A torque converter line 136 is led to this valve 92 from the regulator valve 61, and a pilot boat 92b provided at one end is connected to a hydraulic pressure branched from the main line 110 and reduced in pressure by a solenoid reducing valve 93. A pilot line 137 is connected thereto. And this line 13
7 is provided with a fourth solenoid valve 94 for lock-up, and when the valve 94 is ON, the spool 92a is located on the right side, so that the torque converter line 136 is connected to the torque converter in-line 138 leading into the torque converter 20. As a result, the internal pressure of the torque converter 20 increases and the lock-up clutch 2
6 is concluded. Also, the solenoid valve 94 is
When the FF is activated and the spool 92a moves to the left, the torque converter line 136 communicates with the lock-up release line 139, lock-up release pressure is introduced into the torque converter 20, and the lock-up clutch 26 is released. It has become.

Further, this hydraulic control circuit 60 includes a line pressure control circuit for controlling the line pressure adjusted by the regulator valve 61.
A throttle modulator valve 95, a duty solenoid valve 96 for operating the valve, and a cutback valve 97 are provided.

The throttle modulator valve 95 is connected to the main line 110 by the solenoid reducing valve 9.
3 and line 137, and a pilot pressure regulated by a duty solenoid valve 96 that periodically opens and closes based on the oil pressure in the line 140 is introduced into one end of the spool 95a. , the throttle modulator pressure is generated in accordance with the duty rate (valve opening time ratio in one cycle) of this duty solenoid valve 96. In that case, the duty rate is determined by the throttle opening of the engine. By introducing the corresponding throttle modulator pressure into the pressure increasing boat 61a of the regulator valve 61 through the line 141, the line pressure adjusted by the valve 61 is set according to the throttle opening of the engine. It will be increased as the degree increases.

The cutback valve 97 also includes a line 142 branched from a line 141 that supplies the throttle modulator pressure to the regulator valve 61, and a pressure reducing boat 61 provided at one end of the regulator valve 61.
The cutback valve 97 is connected to the line 143 leading to the line 14b, and one end of the cutback valve 97 is connected to
A modulator pressure boat 97C is provided which is branched from 2 and into which throttle modulator pressure is introduced via line 144. Further, the intermediate portion and the other end portion of the valve 97 are provided with first and second control bows) 97d.

97e is provided, and the first control boat 97d includes D, 2
．． In the first gear of lunge, the first solenoid valve 66
The pilot pressure generated when is OFF is the line 145.
A line 131 that supplies coast clutch pressure from the 2-3 shift valve 64 to the coast clutch 42 at the 2nd speed of the 2nd range and the 1.2nd speed of the lunge is introduced into the second control port 97e. Coast clutch pressure is introduced through the line 146. And these control boats 97d, 97
The first and second spools 97a and 97b move according to the introduction state of pilot pressure and coast clutch pressure to e,
Both hydraulic pressures are not introduced together, and the first spool 97a
is located on the left side, the lines 142 and 143 communicate with each other, and the throttle modulator pressure is introduced into the pressure reducing boat 61b of the regulator valve 61, thereby controlling the first speed of the D range and the first and second speeds of the second range. and 1 of Lunge,
Line pressure is reduced at gears other than 2nd speed.

In addition to the above configuration, this hydraulic control circuit 60 also includes a bypass valve 101.2-3 control valve in addition to the coast control valve 83 for adjusting the supply and discharge timing of hydraulic pressure during each gear shift. 102
, and a timing valve 103.

Among these, the coast control valve 83 is connected to the line 127 which is branched from the servo release line 126 and leads to the coast clutch line 128, as described above.
Servo release pressure from the line 127 and line pressure (forward clutch pressure) from a line 147 branched from the forward clutch line 116 are introduced as control pressures. When the 2-3 shift up in the 2-range is performed, the spool 83a moves to the right side and supplies coast clutch pressure when the servo release pressure rises sufficiently, and when the 2-4 brake 45 is completely released. It is supposed to be done.

Further, the bypass valve 101 is provided on a bypass line 148 that bypasses the one-way orifice 76 provided in the 3-4 clutch line 121, and is installed on the hydraulic pressure (3-4 clutch pressure) and a throttle modulator pressure led from the throttle modulator valve 95 via lines 149, 150 are introduced as control pressures. During a 2-3 upshift, when the 3-4 clutch pressure rises above a predetermined value and the spool 101a moves to the left, the bypass line 148 is cut off and the 3-4 clutch pressure increases. At the beginning of supply, the bypass line 148 supplies the fluid quickly, and then the one-way orifice 76 supplies the fluid slowly.

Furthermore, the 2-3 control valve 102 is provided on the bypass line 151 that bypasses the one-way orifice 81 that performs a throttling action in the hydraulic pressure supply direction on the servo release line 126, and is installed on the 3-4 clutch line 126.
1 (3-4 clutch pressure), throttle modulator pressure led via line 149 and line 152, and servo release pressure downstream of the bypass line 151. Then, the spool 102a moves according to these oil pressures to connect the bypass line 1.
By opening or closing 51, the servo release pressure is regulated in accordance with the 3-4 clutch pressure and the throttle modulator pressure.

Further, the timing valve 103 has a first bypass line 153 that bypasses the one-way orifice 73 on the servo apply line 120, and a one-way orifice 82 (and 81) on the servo release line 126.
a second bypass line 154 that bypasses the above-mentioned 3-
It is provided across a third bypass line 155 that bypasses the fixed orifice 78 (and one-way orifice 79) in the second drain line 123 of 4 clutch pressure. A pilot line 157 led from the main line 110 via a line 156 is connected to one end of the spool 103a.
A fifth solenoid pulp 104 is provided.

This timing valve 103 opens the first to third bypass lines 153, 154, 155 by the operation of the fifth solenoid valve 104, and 3J! 1-2 downshift, 3-2 downshift, and 4
-2 The timing of supplying and discharging hydraulic pressure during downshifting is appropriately controlled.

In addition to the hydraulic control circuit 60 configured as described above, the automatic transmission 10 according to this embodiment includes the first to fifth solenoid valves 66, 67, 68, 94, as shown in FIG.
, 104 and a controller 160 that electrically controls the operation of the duty solenoid valve 96.

This controller 160 receives signals from a vehicle speed sensor 161 that detects the vehicle speed of the vehicle, a signal from a load sensor 162 that detects the engine load, and a range sensor 163 that detects the range selected by the driver.
The signal from the and,
The controller 160 compares the preset shift pattern in each range with the actual driving condition B (vehicle speed and engine load) based on each input signal, and selects a gear position according to the current driving condition. At the same time as the selection, a control signal is output to the first to third solenoid valves 66 to 68 for shifting so that the ON/OFF combination is selected to obtain the selected gear. Further, the fourth solenoid valve 9 is configured to control the lock-up clutch 26 according to the operating state.
4, and also outputs a control signal to the duty solenoid valve 96 to adjust the line pressure according to the engine load, and also outputs a control signal to the duty solenoid valve 96 to adjust the line pressure according to the engine load, and also outputs a control signal to the duty solenoid valve 96 during a 1-2 shift up shift, a 3-2 shift up shift, and 4-2 A control signal is output to the fifth solenoid valve 104 to appropriately control the timing of supplying and discharging hydraulic oil during upshifting.

Next, the structure and operation of the characteristic portion of the actual product will be explained using FIGS. 4 to 6.

As shown in an enlarged view in FIG. 4, the timing valve 103 has a spool 103a and a spring 103b that biases the spool to the right side in the drawing. It is installed on the bypass line 153 provided in the line 120 that supplies servo apply pressure to the apply boat 45a° of the servo piston 45°. Also, a pilot boat 1 is attached to the right end of this timing valve 103.
A line 157 equipped with a fifth solenoid valve 104 is connected to the boat 103c. Then, the first solenoid valve 66 is turned off and then turned off.
At the time of the 1-2 shift up shift in which the switch is switched to N and the servo apply pressure is supplied from the 1-2 shift valve 63 to the line 120, first, the fifth solenoid valve 1O
4 also switched from OFF to ON and pilot boat 10
As the pilot pressure is discharged from 3c, the spool 103a of the timing valve 103 moves to the right, and the bypass line 153 opens. Then, the fifth solenoid valve 104 is turned off again and the spool 103a moves to the left, thereby
The bypass line 153 is cut off. Therefore, 1-
2. During upshifting, the servo abline pressure is rapidly supplied to the apply boat 45a' of the servo piston 45'' via the bypass line 153 at the beginning of the shifting operation, and at the later stage of the shifting operation. It is gradually supplied through the one-way orifice 73, thereby allowing the 1-2 shift up to be performed smoothly without causing any shift shock or delay in shift operation.

This timing valve 103 is also controlled during the N-D operation to perform the action of reducing the ND shock, and this action is then controlled by the control operation of the controller 160 whose flowchart is shown in FIG. I will explain according to the following.

First, in step S1 of the flowchart, the controller 160 reads the current time t and the range R indicated by the signal from the range sensor 163, and then in step S2
Then, it is determined whether the range R is "D". If the result is other than "D", in step S3, the normal pattern shown in Table 2 above is adopted as the ON/OFF combination pattern of the first to third solenoid valves 66 to 68, and in step S4, The first one should follow this pattern.
- Outputs a control signal to the third solenoid valves 66-68. Here, as shown in FIG.
The F pattern is the same, and the first solenoid valve 66
is OFF, and the second and third solenoid valves 67 and 68 are O.
It is N.

Also, at this time, the timing valve 103 shown in FIG.
The fifth solenoid valve 104 that controls the operation of is OFF.
It is.

Further, when the range R is "D", the controller 160 determines the range R' detected in the previous control cycle in step S. And this previous range R'
is not “D” or °゛N, the above step S
,, In S4, control signals are output to the first to third solenoid valves 66 to 68 so as to have a normal ON/OFF pattern.

On the other hand, when the current range R is °°D'° and the previous range R° is N'', that is, when the ND operation is performed, the controller 160 performs step S2. Step S6 is executed from S, and the time t at that point is set as the ND operation start time ts. And step S7
Then, it is determined whether the elapsed time (tts) from the start time ts to the current time t exceeds a predetermined time to,
In addition, from the next control cycle onward, step S7 is executed without setting the operation start time ts in step S6, and it is similarly determined whether the elapsed time has exceeded the predetermined time to.

Then, until the elapsed time from the start of the operation exceeds the predetermined time to, the controller 160 executes step S8 and turns on the first to third solenoid valves 66 to 68.
, all ON N-D shown in Figure 6 as an OFF pattern.
In addition to adopting the pattern for operation, the fifth solenoid valve 104 is also set to ON, and a control signal is outputted so as to adopt this pattern in step S4. Then, after that, the predetermined time t. When the time has passed, execute steps S, S4 from step S to normal ON/OFF.
In this case, the control signal is output so that the first to third solenoid valves 66 to 68 are in the first speed pattern, and the fifth solenoid valve 104 is in the OFF turn. In that case, the first to third solenoid valves 6
The patterns 6 to 68 for the N-D operation are the 2nd speed patterns, that is, the no-turns in which the forward clutch 41 and the 2-4 brake 45 are engaged, as shown in Table 2 above.

And solenoid valves 66-68.10 like this
4, the 1-2 shift valve 63 and timing valve 103 shown in FIG. 4 operate as follows.

That is, first, due to the movement of the spool 62a of the manual valve 62 due to the N-D operation, the forward clutch 41
A first output line 111 (forward clutch line 116) leading to the main line 110 is connected to the main line 110, and forward clutch pressure is supplied to the clutch 41.
When the first solenoid valve 66 is turned ON and the spool 63a of the 1-2 shift valve 63 moves to the right, the first output line 111 is communicated with the servo brine line 120, and the servo piston 45' is applied. Servo apply pressure is supplied to port 45a'.

At this time, the fifth solenoid valve 104 is also turned ON, so that the servo apply line 1
Bypass line 153 that bypasses one-way orifice 73 on 20 is opened, so that servo apply pressure is quickly supplied to apply boat 45a'. On the other hand, the first output line 111
As shown in FIG. 2, a one-way orifice 71 is provided in the line 116 which is branched from the line 116 and supplies forward clutch pressure to the forward clutch 41.
Compared to the servo apply pressure that is quickly supplied by the bypass line 153, the supply of forward clutch pressure is slow, so the forward clutch 41 is engaged after the 2-4 brake 45 is engaged. Or at least the forward clutch 41 is not engaged before the 2-4 brake 45 is engaged.

This prevents the forward clutch 41 from being engaged before the 2-4 brake 45 and switching from the neutral state to the first speed during the N-D operation, and ensures that the neutral state changes to the second speed. Then, after the predetermined time to has elapsed, the first solenoid valve 66 and the fifth solenoid valve 104 are turned off, and the gear stage is changed to 1.
The vehicle switches to high speed and becomes ready to start.

Here, in this embodiment, the pattern for N-D operation is set for a predetermined time t. The period is until the end of the first period.
The rotational speed of the turbine shaft 27 shown in the figure may be detected and the period may be a period until the speed decreases to a predetermined value or less.

Furthermore, the above configuration can be similarly applied during the N-R operation, and in this case, the operation causes the
For example, the forward clutch 41 and the 2-4 brake 45 are controlled to be engaged, and at this time the bypass line 153 of the servo apply line 120 is opened, and then the reverse clutch 44 and the low reverse brake 46 are engaged. ! It becomes i.

(Effects of the Invention) As described above, according to the present invention, during N-D operation or N-D operation,
- In an automatic transmission that is configured to pass through a predetermined gear position of 2nd speed or higher during the R operation, the throttle element provided in the hydraulic pressure supply passage to the friction engagement element that is engaged at the predetermined gear position during the above operation is bypassed. Since hydraulic pressure is supplied to the frictional engagement element by the friction engagement element, the engagement operation of the frictional engagement element is performed in one step.
This prevents a delay in the engagement operation of the frictional engagement element that is engaged in all forward gears including the forward speed, and ensures that the neutral state is switched to the above-mentioned predetermined gear. As a result, even though it is controlled to go through a high gear, it switches from neutral to 1st gear,
A large shock is prevented from occurring, and the N-D or N-H switching operation is performed satisfactorily.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a schematic diagram showing the mechanical configuration of an automatic transmission, FIG. 2 is a circuit diagram showing a hydraulic control circuit, and FIG. 3 is a block diagram showing an electrical control circuit. figure,
Figure 4 is an enlarged view of the main parts of the above hydraulic control circuit;
The figure is a flowchart showing the control operation during N-D operation,
Figure 6 shows the ON and OFF states of the solenoid valve during this operation.
FIG. 3 is an explanatory diagram of an FF pattern. 10... Automatic transmission, 30... Speed change gear mechanism, 41
~46...Friction engagement element, 60...Hydraulic control circuit,
73... Aperture element (one-way orifice>, 103
, 104... Opening/closing means (timing valve, solenoid valve), 120... Hydraulic pressure supply passage (servo apply line), 153... Bypass passage, 160...
Control means (controller). Figure 3 60 572- Figure 5

Claims (1)

[Claims] (1) A control device for an automatic transmission comprising a speed change gear mechanism, a plurality of friction engagement elements that switch the power transmission path of the speed change gear mechanism, and a hydraulic control circuit that selectively engages these friction engagement elements. The hydraulic control circuit includes a throttle element that throttles the hydraulic pressure supply passage to the frictional engagement element engaged at a predetermined gear stage of second speed or higher, a bypass passage that bypasses the throttle element, and an opening/closing mechanism that opens and closes the bypass passage. and means for setting the engagement state of each friction engagement element for a predetermined period so that the predetermined gear stage is achieved during a shift operation from the N range to the D range or the R range, and A control device for an automatic transmission, comprising: a control means for driving an opening/closing means to open the bypass passage during a period.