JP2911121B2 - Control device in automatic transmission and cutback valve used therefor - Google Patents

Description

The present invention relates to a control device for an automatic transmission mounted on an automobile in an automatic transmission or the like, and more particularly, to a cut device that applies a line pressure in a pressure increasing direction. The present invention relates to a hydraulic pressure control device for a back pressure and a structure of a cutback valve thereof.

(B) Conventional technology Conventionally, a cut-back valve is installed in a hydraulic control device of an automatic transmission, and the cut-back valve is provided to a hydraulic servo for a second brake which is supplied with a hydraulic pressure at the second speed or higher. It has a control chamber communicating therewith, an input port to which the throttle pressure is supplied, and an output port acting on the throttle valve using the throttle pressure of the input port as a cutback pressure.

At the time of first speed, the cutback valve is in a position where the input port and the output port are shut off due to no hydraulic pressure being supplied to the hydraulic servo for the second brake,
Do not supply cutback pressure to the throttle valve. In this state, the cut-back pressure does not act on the return side of the spool, the throttle valve regulates the line pressure to a relatively high throttle pressure, and acts on the primary regulator valve to apply the throttle pressure to the line. The pressure is set relatively high, thereby generating a high clutch engagement force corresponding to the high load torque at the time of starting. Also,
At the second speed or higher, the cutback valve is switched so that the input port and the output port communicate with each other based on the supply of hydraulic pressure to the hydraulic servo for the second brake, and the cutback pressure acts on the throttle valve. . In this state, the cut-back pressure acts on the return side of the spool of the throttle valve to generate a relatively low throttle pressure, and the throttle pressure acts on the primary regulator valve to relatively reduce the line pressure. It is set low, thereby reducing the clutch and brake engagement forces to reduce shift shock.

(C) Problems to be Solved by the Invention In the line pressure control described above, even if it is in two ranges,
At the 2nd speed, the cut-back valve is in the communicating state, and the line pressure is set lower. Therefore, when starting from the 2nd speed at the time of escaping from the stag state or starting on a snowy road, the line pressure is also lower. Therefore, the engagement force of the friction engagement device is insufficient, and the second speed start cannot function effectively.

Thus, the present invention provides, for example, a 2 (S) range.
Automatic shifting that sets the line pressure to be high during high-speed start such as quick start, eliminates the shortage of the engagement force of the frictional engagement device (element), and ensures that high-speed start is ensured It is an object of the present invention to provide a control device in a machine and a cutback valve used therefor.

(D) Means for Solving the Problems The present invention has been made in view of the above-described circumstances, and a transmission gear device (3) for changing over to a plurality of gears by changing a transmission path, and a predetermined gear device for the transmission gear device. A hydraulic servo for frictional engagement elements (B ₁ , B ₂ …) for engaging or disengaging the elements, and a primary regulator valve (52) for regulating a line pressure supplied to the hydraulic servos. In the automatic transmission control device, wherein the line pressure is set so as to be higher at the lowest gear (first speed) than at higher speeds other than the lowest gear. The hydraulic servo (B ₁ ) for a high speed start-up friction engagement element that directly engages the predetermined element (30) when starting at a predetermined high speed (for example, (2S) range 2nd speed) other than the minimum shift speed described above. To supply the line pressure to Hazuki, the primary regulator valve (52)
Is set so that the line pressure becomes high similarly to the lowest speed.

A transmission gear device (3) for changing the transmission path to a plurality of gears; and a hydraulic servo (B ₁ , B ₂ ...) For engaging and disengaging predetermined elements of the transmission gear device. ,
A primary regulator valve (52) that regulates the line pressure supplied to these hydraulic servos, and a throttle valve (53) that generates a throttle oil pressure corresponding to the engine output.
A cut-back valve (59) that is used in a control device of an automatic transmission and includes a spool (59a) that is urged in one direction and generates a cut-back pressure at a predetermined gear position. A first control chamber (o ₁ ) disposed opposite the urging direction, a second control chamber (s) disposed sequentially in the urging direction, and the throttle pressure. A predetermined hydraulic servo having an input port (q), an output port (j ₁ ) for supplying the cut-back pressure to the primary regulator valve, and a drain port ( _EX ), to which hydraulic pressure is supplied at a second speed or higher; (B ₂₎
Is communicated to the first control room (o ₁ ), and the hydraulic servo (B ₁ ) for the second speed engine brake is communicated to the second control room (s). And generating the cutback pressure for setting the line pressure higher. The cutback valve used in the control device of the automatic transmission.

More specifically, referring to FIG. 1, for example, a clutch or brake hydraulic servo for engaging or disengaging a predetermined element of the transmission gear device, and a primary pressure adjusting line pressure supplied to these hydraulic servos are provided. It is provided with a regulator valve (52), an output corresponding valve that generates a hydraulic pressure corresponding to the engine output, for example, a throttle valve (53), and a cutback valve (59) that generates a cutback pressure at a predetermined gear position. In the hydraulic control device for an automatic transmission, the cutback valve (59) has a spool (59a) biased in one direction, and the first control chamber (o) is opposed to the biasing direction. with the second control chamber Ji order urging direction (s) is provided with a _1), further input port for inputting a hydraulic pressure (e.g., throttle pressure) corresponding to the engine output (q), the hydraulic The primary regulator valve (52) or output corresponding to the supplied output port valve (53) (j ₁₎ and provided with a drain port _(EX), a predetermined hydraulic servo oil pressure is supplied at the second speed or more (e.g. 2nd
The brake hydraulic servo B ₂ ) communicates with the first control chamber (o ₁ ), and the brake hydraulic servo (2nd coast brake hydraulic servo) regulates the coast state at the second speed.
B ₁ ) is communicated with the second control chamber (s), and the line pressure is set to be higher during the second-speed coast regulation as in the case of the first speed.

As an example, the output corresponding valve is a throttle valve (53) that operates according to the throttle opening, and the output port (j ₁ ) of the cutback valve (59) is connected to the primary regulator valve (52). It communicates with the cutback pressure port (j).

The cutback valve (59) is connected to the spool (59
a), a spring (59
b) a first control chamber (o) formed at the other end of the spool.
₁ ) and a second control chamber (s) formed at one end of the spool and containing the spring, further comprising an input port (q), an output port (j ₁ ) and a drain port ( _EX ). It has.

(E) Action Based on the above configuration, when starting at a predetermined high speed other than the lowest speed operated by the manual operation means, for example, at the second speed start in the 2 (S) range, the predetermined element is directly engaged. The line pressure is supplied to the hydraulic servo of the friction engagement element at the time of high-speed start (for example, the hydraulic servo B ₁ for the second coast brake) in order to start.

Utilizing the line pressure supply to the hydraulic servo (B ₁ ), the primary regulator valve (52) operates the lowest speed stage (1).
As in the case of (Speed), the line pressure is set higher.

Specifically, at the first speed in the D range, the cutback valve (59) is located at, for example, the left half position by the urging force of the spring (59b), and the input port (q) and the output port (j ₁ ) are connected. Communicating. In the this state, cutback of the output corresponding valve through output corresponding pressure from (throttle valve) (53) (throttle pressure) port (q) and (j _1), for example, a primary regulator valve (52) Pressure port (j). Thereby, the regulator valve (52) sets the line pressure of the line pressure port (p ₂ ) to be higher. Also, 2 in the D range
If the speed is higher than the speed, hydraulic servo for the 2nd brake (B ₂ )
The line pressure acts on the first control chamber (o ₁ ) due to the hydraulic pressure acting on the first control chamber (o ₁ ), the cutback valve (59) is switched to the right half position, and the output port (j ₁ ) is connected to the input port (j ₁ ). q)
And communicate with the drain port ( _EX ). As a result, the hydraulic pressure does not act on the cutback pressure port (j), and the primary regulator valve (52) sets the line pressure lower.

Then, connect the manual valve (51) (Fig. 4) to 2
(S) If you select the range, in the second gear state,
The line pressure is supplied to the 2nd coast brake hydraulic servo (B ₁ ), and the line pressure acts on the second control chamber (s) of the cutback valve (59). In this state, 2n
d Brake hydraulic servo (B ₁ )
Although the line pressure is also supplied to the control room (o ₁ ), the cutback valve (59) is located at the left half position based on the spring (59b), and communicates with the ports (j ₁ ) and (q). Then, by applying the cutback pressure, the line pressure is set higher as in the case of the first speed in the D range. As a result, a strong engagement force acts on the friction engagement device, and the second speed start functions effectively.

In addition, although the code | symbol in parenthesis is for contrast with drawing, it does not limit the structure of this invention at all.

(C) Example Hereinafter, an example of the present invention will be described with reference to the drawings.

As shown in FIGS. 2 and 3, the automatic transmission 1 includes a torque converter 2, a planetary transmission gear mechanism 3, and a hydraulic control device 5, and includes a converter housing 6, a transmission case 7, an extension housing 9, And valve body 10 and oil pan
Stored in 11. The torque converter 2 is provided with a lock-up clutch 12, and the rotation of the input member 13 is controlled via the oil flow of the torque converter 2 or the lock-up clutch.
The power is directly transmitted to the input shaft 15 of the speed change gear mechanism 3 by 12. Transmission gear mechanism 3 is an overdrive planetary gear unit
And a main transmission unit 21 including a front planetary gear unit 19 and a rear planetary gear unit 20. The overdrive planetary gear unit 17 is directly connected to the input shaft 15 and supports a planetary pinion 22, a sun gear 23 fitted on the input shaft 15, and a ring gear connected to the input shaft 26 of the main transmission unit 21.
25, planetary carrier 24 and sun gear
23, an overdrive direct clutch C ₀ and a one-way clutch F ₀ are interposed.
Overdrive brake B ₀ is arranged between the case 7 and. The front planetary gear unit 19 is directly connected to the output shaft 27 and supports the planetary pinion 28.The carrier 29, the sun gear 30a fitted on the output shaft 27 and integrally formed with the sun gear 30b of the rear planetary gear unit 20, and through the forward clutch C ₁ on the input shaft 26 is a ring gear 31 which are coupled, the input shaft
Between 26 and sun gear 30 along with the direct clutch C ₂ is interposed, 2nd coast brake B ₁ consisting of a band brake is interposed between the sun gear 30 and the case 7, further sun gear 30 and the case 7 2nd brake B ₂ consisting of multi-plate via a one-way clutch F ₁ is disposed between the. The rear planetary gear unit 20 includes a carrier 33 supporting a planetary pinion 32 and a sun gear.
Is a ring gear 35 which is directly connected to 30b and the output shaft 27, also it is arranged in parallel 1st & Rev brake B ₃ and the one-way clutch F ₂ is between the carrier 33 and the case 7. In FIG. 2, reference numeral 36 denotes an oil pump.

Then, as shown in FIG. 2, in the O / D planetary gear unit 17, the boss portion 23a of the sun gear 23 extends in the axial direction,
The one-way clutch F ₀ is interposed between the sleeve 24a fixed to the boss portion and the carrier 24, also a flange portion 40 constituting the cylinder from the boss portion 23a is extended. The said flange 40 and the piston 41 is fitted constitutes a hydraulic actuator for C _0, is further O / D direct clutch C ₀ is disposed between the sleeve 24a and the flange portion peripheral surface An O / D brake _B0 is disposed between the outer peripheral surface and the case 7, and an annular flange portion 42 is fixed to the flange portion 40 so as to extend in the outer diameter direction. . Further, a non-contact sensor 45 such as light or magnetism is provided in the case 7 so as to face a large number of holes or notches formed in the flange 42. The sensor 45 includes an O / D direct clutch. connected i.e. the first speed of C _0, 2 speed, to detect the rotational speed of the flange portion 42 integral with the input member 15 to the third speed.

On the other hand, a vehicle speed sensor 46 for detecting rotation of the output shaft 27 is provided in the extension case 9, and signals from the vehicle speed sensor 46 and the speed sensor 45 are sent to the control unit C together with signals from other sensors. , A hydraulic control device 5 described later
Control the respective solenoid valves S1, S2, S3, S4.

Also, the driver's seat has a select lever and accelerator pedal,
A brake pedal and the like are provided (not shown), and the select lever is operated in conjunction with a manual valve 51 (FIG. 4) to be described later to set the valve to neutral N, drive D, reverse R, second 2, low L. The position sensor 47 (FIG. 1) detects the movement of each position (in particular, the N range to the D range and the R range). Also, the accelerator pedal is a throttle and a throttle valve 53 described later.
(FIG. 4) through a wire or the like, and the throttle opening is detected by a throttle sensor 49. The throttle sensor 49 is a start sensor that detects the start operation of the driver. However, the start sensor is not limited to the throttle sensor, and may be another sensor such as a sensor that detects a release operation of the brake pedal depression operation. The good thing is, of course.

Next, the hydraulic control device 5 will be described with reference to FIG.

In the figure, C ₀ , C ₁ , C ₂ indicate the hydraulic servos of the respective clutches, B ₀ , B ₁ , B ₂ , B ₃ indicate the hydraulic servos of the respective brakes, further 2 indicates a torque converter, and 12 indicates The lock-up clutch 36 is a hydraulic pump. Reference numeral 51 denotes a manual valve, and at each position P, P, N, D, 2, L, the line pressure port p has a corresponding port a, b, c, d indicated by a circle in the figure.
Communicate with Further, reference numeral 52 denotes a primary regulator valve which regulates a line pressure supplied to each hydraulic servo, and its structure will be described later in detail. Further, 53 is a throttle valve, 55 is a semandary regulator valve, 56 is a lock-up control valve, 57 is a lock-up relay valve, 58 is a solenoid relay valve, and 59 is a cutback valve according to the present invention. Also, 60 is 1-
2 shift valve, 61 is 2-3 shift valve, 62 is 3-4
A shift valve, 63 is a reverse inhibit valve, 65 is a low coast modulator valve, and 66 is a second coast modulator valve. Then, the C ₀ accumulator 67 69 B ₀ accumulator, the C ₂ accumulator 70, 71 is a B ₂ accumulators. Also, 72 is the B ₀ accumulator 69, C ₂ accumulator 70 and B ₂
The hydraulic pressure communicating with the back pressure chambers 69a, 70a, 71a of the accumulator 71 is adjusted, and the low coast modulator valve 65 and the second coast modulator valve 66 are adjusted.
This is an accumulator control valve for controlling the pressure adjustment. Further, S1 and S2 are solenoid valves for switching and controlling the shift valves 60, 61 and 62, respectively, and S3 is a linear solenoid valve, which adjusts the oil pressure from the solenoid regulator valve 73 as needed. The hydraulic pressure is supplied to the accumulator control valve 72. S4 is a linear solenoid valve, which supplies a control pressure to the lock-up control valve 56 and the lock-up relay valve 57 as appropriate, and performs a line pressure control described later.

Next, the line pressure control portion according to the present invention will be described with reference to FIG.

The primary regulator valve 52 has a main spool
52a, the sub-spool 52b, and the plug 52c have three moving members that abut against each other and slide together, and the main spool 52a has a feedback port f acting on the lower end thereof, and acts on a stepped portion. It has a control chamber port e, a line pressure port p ₂ , a port h communicating with the secondary regulator valve 55, and a drain port _EX . Furthermore,
The sub spool 52b has a throttle pressure port i acting on its upper end and a cutback pressure port j acting on its step, and its plug 52c has an R range line pressure port d acting on its upper end. Have _one .
The line pressure port p ₂ communicates with the discharge side of the hydraulic pump 36 to adjust the pump pressure to the line pressure and to control each hydraulic servo C ₀ , C ₁ , C ₂ , B ₀ , B ₁ , B ₂ , resulting communicates with the B _3, also the line pressure is also communicated with the input port p ₃ and are also supplied to the line pressure port p ₄ of the throttle valve 53 and pre-shear relief valve 75, the solenoid modulator valve 73. The hydraulic pressure from the port h communicates with the secondary regulator valve 55 to be adjusted to the converter hydraulic pressure, and is supplied to the torque converter 2 via the lock-up relay valve 57.
d ₁ is the line pressure when the manual valve 51 is select the R-range is communicated with the port d supplied (Fig. 4).

On the other hand, the solenoid relay valve 58 with a spool 58a is urged downward by a spring 58b, a control chamber o communicating with the hydraulic servo B ₂ for 2nd brake the lower end
And an input port k, a first output port e ₁ ,
A drain port _EX and a second output port l,
The input port k communicates with the ports k ₁ and k ₂ of the lock-up solenoid valve S4, the first output port e ₁ communicates with the control chamber port e of the primary regulator valve 52, and the second output port 1 communicates with the fourth As shown, the lock-up control valve 56 and the lock-up relay valve 57
In the control rooms l ₁ and l ₂ . The lock-up solenoid valve S4 is composed of a linear solenoid valve,
An input port m, an output port k ₁ , a throttle port k _2, and a drain port _EX are provided. The supply pressure from the input port m is appropriately adjusted by an electric signal from the control unit C and output to the output port k ₁ . I do. Further, the solenoid modulator valve 73 to the input port m, hydraulic pressure is supplied the line pressure the (p ₃₎ from the port m ₁ the pressure was reduced to a predetermined pressure.

On the other hand, the throttle valve 53 is a downshift plug 53a.
And consists of two moving members of the spool 53b, the throttle cam 53c downshift plug 53a is being linked via an accelerator pedal and a wire or the like at its upper end is in contact with, and the throttle from the port i ₂ to the plug The pressure acts to constitute a power assist mechanism for reducing the pressing force of the throttle cam 53c. The line pressure port p ₄ to the spool 53b portion, a throttle pressure port i _3, provided with a feedback port i ₄ and the drain port _EX,
Compressing the spring 53b via the plug 53a in accordance with the rotation amount of the throttle cam 53c, to move the spool 53b as the biasing force of the biasing force and the feedback port i ₄ and the lower end spring 53e of the spring 53d is balanced, the throttle cam (hence the throttle pedal) based on the movement amount of the spool 53b corresponding to the amount of rotation of, causing the throttle pressure to the throttle pressure port i ₃ by the line pressure of the line pressure port p ₄ tone. Note that the lower end spring 53e can be adjusted by a screw 53f.

Further, the cut-back valve 59 together with the spool 59b is urged downward by a spring 59b, to the upper end of the spool 59a is a top control chamber s communicating with the hydraulic servo B ₁ for 2nd coast brake And has a lower control room o ₁ at the lower end thereof, and further has an input port q, an output port r, and a drain port _EX.
o ₁ is a hydraulic servo B ₂ for the 2nd brake together with the control chamber o of the solenoid relay valve 58 shown in FIG.
Is in communication with

 Next, the operation of the present embodiment will be described.

Each solenoid valve S1 of the automatic transmission 1, S2, S4, the clutches _{C 0, C 1, C 2} , brake _{B 0, B 1, B 3} , and the one-way clutch F _0, F _1, F ₂ is Each position (range) P, R, R
(V ≧ 7), and control is performed as shown in the operation table of FIG. 5 at the shift speeds of N, D, 2, and L.

That is, at the 1st speed in the D range or 2 range, the solenoid valve S1 is in the ON state, and as a result, the overdrive direct clutch C ₀ , the one-way clutches F ₀ , F
₂ and the forward clutch C ₁ is engaged, the other is in a released state. Thus, the overdrive planetary gear unit 17 has a directly coupled together via the clutch C ₀ and the one-way clutch F _0, the rotation of the input shaft 15 is transmitted to the input shaft 26 of the intact main speed change unit 21 . Further, the main transmission unit 21, the rotation of the input shaft 26 is transmitted to the ring gear 31 of the front planetary gear unit 19 through the forward clutch C _1, it is further transmitted to the carrier 29 and the output shaft 27 integral with the carrier 29 ,
Imparting a rotational force in the leftward direction to the carrier 33 of the rear planetary gear unit 20 through the sun gear 30, but the rotation is prevented by the one-way clutch F _2, planetary pinions 32
Rotates and transmits power to a ring gear 35 integrated with the output shaft 27.

When the manual valve 51 is selected from the N range to the D range, a predetermined signal is output from the control unit C to the linear solenoid valve S4 based on a signal from the position sensor 47. Then, the solenoid modulator valve
Hydraulic pressure from the output port m of 73 is output from port k ₁ and pressure regulated to a predetermined hydraulic pressure is supplied to the input port k of the solenoid relay valve 58. At this time, the solenoid relay valve 58 is in the left half position without hydraulic pressure acting on the control room o based on the release of the _second brake B2. Accordingly, the control pressure port k is supplied to the control chamber e of the primary regulator valve 52 via the port e _1. In the this state, the primary regulator valve 52, a throttle pressure from the throttle valve 53 is supplied to the port j, and the left half position based on the release cutback valve 59 is 2nd coast brake B ₁ and 2nd brake B ₂ by in port q, throttle pressure is applied to the port j through j _1, thereby it is in a state of biasing the spool 52a downward to generate a relatively high first speed line pressure, the The line pressure is reduced by a predetermined amount based on the supply of the control pressure to the control room e. Thereby, N of the manual valve 52 →
When D select, line pressure is depressurized, thus overdrive under reduced pressure the supply pressure of the direct to the clutch hydraulic servo C ₀ and the hydraulic servo C ₁ for forward clutch, smooth the clutch C _0, oncoming of C ₁ Then, based on a signal from the control unit C, the control pressure from the linear solenoid valve S4 is slowly reduced by timer control, and the line pressure from the primary regulator valve 52 is returned to the normal state, so that the clutches C ₀ , C ₁ To ensure engagement. At this time, the cut-back valve 59 In the left half position by the biasing force of the spring 59b, which communicates with the input port q output port j _1, therefore, the throttle pressure port q from the throttle valve 53, j ₁ Through the primary regulator valve 52
Is supplied to the cutback pressure port j. This allows
The main spool 52a is urged downward through the sub-spool 52b to set a high line pressure and exert a strong clutch engagement force in response to a high load at the time of starting. Note that emits a signal from the control unit C with a signal from the start sensor 49 such as a throttle sensor 49, when the driver's seat does not start intention of such steps on the accelerator pedal, the line pressure clutch C _0, C ₁ torque By keeping the oil pressure just before transmission, the creep phenomenon at the time of N → D selection may be prevented.

At the 2nd speed in the D range, the solenoid valve
In addition to turning on S1, valve S2 switches on. As a result, the overdrive direct clutch C ₀ , the one-way clutch F ₀ , the forward clutch C ₁ , the one-way clutch F ₁ and the second brake B ₂ are engaged, and the others are released. Therefore, the overdrive planetary gear unit 17
Is in the directly connected state described above, and the rotation of the input shaft 15 is transmitted to the input shaft 26 of the main transmission unit 21 as it is. The main transmission unit 21 transmits the rotation of the input shaft 26 to the ring gear 31 of the front gear unit 19 via the forward clutch ₁ and applies a leftward rotational force to the sun gear 30 via the pinion 28. 30 rotation of the direction is prevented by the one-way clutch F ₁ due to the engagement of the 2nd brake B _2, thus planetary pinion 28 carrier 29 rotates while rotating, the second speed only via the front gear unit 19 The rotation is transmitted to the output shaft 27.

At this time, due to the line pressure supply to the hydraulic servo B ₂ for 2nd brake, solenoid relay valve 58 is supplied with the line pressure to the control chamber o switched to the right half position, the input port k is the second output A linear solenoid valve S is connected to the control chambers l ₁ and l ₂ of the lock-up control valve 56 and the lock-up relay valve 57, respectively.
The control pressure from 4 can be supplied. Thus, the lock-up solenoid valve S4 is appropriately controlled by a signal from the control unit C based on signals from the speed sensor 46, the throttle sensor 49, and the like, and the lock-up clutch 12
Is controlled.

Further, due to the line pressure supply to the hydraulic servo B ₂ for 2nd brake, cut-back valve 59 is switched to the right half position line pressure is supplied to the control chamber o _1. In this state, the port j ₁ communicates with the drain port _EX with the throttle pressure port q is closed, the port j of the primary regulator valve 52 becomes the drain state. Therefore, the valve 52 reduces the force for urging the spool 52a downward, and sets the line pressure to a relatively low value corresponding to the second speed or higher. In the state of 2nd or higher, 2nd, 3rd and 4th
At a speed higher than the speed, the line pressure is supplied to the _second brake hydraulic servo B2, and the line pressure is maintained at the relatively low line pressure.

Further, when the hydraulic pressure is supplied to the hydraulic servo for the 2nd brake friction plates are of the brake B ₂ starts contacting, overdrive its output torque is changed, and rotated integrally with the result input shaft 15 Planetary gear unit
The rotation speed of the 17 flange portions 40 changes. The change in the rotational speed is detected by the sensor 45, the linear solenoid valve S3 is controlled by a signal from the control unit C based on the detection, and the control pressure is generated by appropriately adjusting the hydraulic pressure from the solenoid modulator valve 73. The control pressure is supplied to the control port of the accumulator control valve 72. As a result, the control valve 72 has been supplying the line pressure to the back pressure chamber 71a of the accumulator 71, but the control pressure is supplied to the back pressure chamber 71a so that the accumulator back pressure becomes a predetermined amount. After a predetermined time, the accumulator back pressure is gradually reduced based on the control pressure from the linear solenoid valve S3, and the output torque changes smoothly. As a result, at the time of the 1st to 2nd speed upshift, the shift shock due to the engagement of the _second brake B2 is reduced, and the upshift is smoothly performed. The reduction of the shock at the time of the shift is not limited to the 1st to 2nd speed, but is similarly performed at the 2nd to 3rd speed and the 3rd to 4th speed.

At the 3rd speed in the D range and the 2nd range, the solenoid S1 is turned off, and the overdrive direct clutch C ₀ , the one-way clutch F ₀ , the forward clutch C ₁ ,
Direct clutch C ₂ and the 2nd brake B ₂ is engaged, the other is in a released state. Accordingly, the overdrive planetary gear unit 17 is in the directly connected state described above, and the main transmission unit 21 is integrated with the front planetary gear unit 19 by the engagement of the two clutches C ₁ and C ₂ to form the input shaft 26.
Is transmitted to the output shaft 27 as it is.

At the 4th speed in the D range, that is, at the highest speed, the solenoid valve S2 is also turned off, and the forward clutch C ₁ ,
The direct clutch C ₂ and the second brake B ₂ are in the engaged state, and the main transmission unit 21 is in the directly connected state as in the case of the third speed. However, the overdrive planetary gear unit 17 releases the brake B when the direct clutch C ₀ is released. ₀ is switched to engage. Accordingly, the sun gear 23 is locked by the brake B _0, planetary and re pinion 22 is rotating with the power transmitted to the ring gear 25 while the carrier 24 is rotated,
The speed increase rotation (overdrive) is transmitted to the input shaft 26 of the main transmission unit 21 in the directly connected state.

On the other hand, when the manual valve 51 is operated in the second range, the operation in the first speed and the third speed is the same as in the case of the D range. And in the case of 2nd gear, forward clutch
In addition to C ₁ , the O / D direct clutch C _0, and the second brake B ₂ , the second coast brake B ₁ is engaged, and locks the sun gear 30 of the main transmission unit 21 to apply engine braking. In the operation table of FIG. 5, the first speed is set in the two ranges as shown in parentheses.
In the two ranges, it is preferable that the vehicle be started from the second speed without the first speed state.

At this time, due to the engagement of the 2nd coast brake B _1,
Cut-back valve 59 is supplied with the line pressure to the upper control chamber s, even when the line pressure based on the engagement of the 2nd brake B ₂ is supplied to the lower control chamber o _1, it is held in the left half position by the spring 59b You. Therefore, the port j of the primary regulator valve 52, the port q, cutback pressure is supplied via j _1, the primary regulator valve 52,
At the second speed in the second range, a relatively high line pressure is generated as in the first speed in the D range. As a result, a strong engaging force is generated in each clutch and brake, and when the vehicle escapes from the stag state and starts on a snowy road, the manual valve 51 is set to two.
It works effectively when selecting to the range and starting in 2nd speed.

Further, at the time of engine braking, the control unit C sends a predetermined signal to the linear solenoid valve S3 based on a signal from the speed sensor 46, and the valve S3 generates a hydraulic pressure to a predetermined pressure according to the vehicle speed. Then, the predetermined hydraulic pressure from the valve S3 is supplied to the accumulator control valve 72, whereby the control valve reduces the line pressure by a predetermined amount and outputs it to the control port. Then, the pressure regulation of the control port is supplied to the control chamber of the second coast modulator valve 66, and regulates the oil pressure from the output port of the valve 66,
Supplying該調pressure 2nd hydraulic servo B ₁ for coast brake. Thus, the modulator valve 66 is supplied hydraulic pressure also in vacuo to the hydraulic servo B ₁ corresponding to the vehicle speed, 2nd coast brake B ₁ represents acts the engine brake while reducing the torque capacity in response to deceleration of the vehicle speed. As a result, the engine brake works smoothly.

The second speed in the L range is the same as the second speed in the two ranges described above, but in the first speed, in addition to the forward clutch C ₁ and the O / D direct clutch C ₀ , the 1st &
Rev brake B ₃ is engaged, the rear planetary gear unit
Lock the 20 carrier 33 and apply the engine brake. Similarly this time, the control pressure based on a signal from the vehicle speed sensor, regulating pressure from the output port of the modulator valve 65 is reduced in proportion to the decrease in the vehicle speed,該調pressure acts on the hydraulic servo B _3. By this, 1st & Rev brake B ₃
In the high speed state, the engine brake is applied with a large torque capacity, and the engine brake is appropriately applied with a gradually reduced torque capacity in response to a decrease in the vehicle inertia due to a decrease in the vehicle speed.

In the R range, the overdrive direct clutch C ₀ , the one-way clutch F ₀ , the direct clutch C ₂
And 1st & Rev engaging the brake B _3, the other is in a released state. Therefore, the overdrive planetary gear unit 17
Is in a directly connected state, and the main transmission unit 21 is connected to the input shaft 26.
Rotation of is transmitted directly to the sun gear 30 by the clutch C _2,
And the rotation of Riakyariya 33 by the brake B ₃ is locked, the rotation of the sun gear 30 planetary pinion
The rotation is transmitted to the ring gear 35 as a reverse rotation through the rotation of the output shaft 32, and the output shaft 27 is rotated in the reverse direction.

At this time, in the same manner as when the manual valve 51 is selected from N to D, when the N to R is selected, a predetermined control pressure is generated by the linear solenoid valve S4 by a signal from the control unit C based on the signal from the position sensor 47. . Then, in the R range, the solenoid relay valve 58 is in the left half position, there ports k and the e ₁ is in communication with, the aforementioned control pressure of the primary regulator valve 52 via the port k and e ₁ The pressure is supplied to the control room e, and the line pressure is reduced by a predetermined amount. Thereby, as described above, the shock at the time of N → R selection is reduced.

Further, in the R range, the line pressure port d of the manual valve 51 is supplied, the line pressure of the port d is supplied to the R-range line pressure port d ₁ of the primary regulator valve 52. In this state, even if the throttle pressure is not supplied from the cutback valve 59, the primary regulator valve 52 exerts a large downward biasing force on the main spool 52a via the plug 52c and the sub-spool 52b, and the line pressure is reduced. Is set higher than in the first speed state. With this, the overdrive direct clutch
C ₀ , direct clutch C ₂ and 1st & Rev brake B
₃ generates a strong engagement force corresponding to the gear ratio.

Also, even if the manual valve 51 is operated to the R range,
If the vehicle speed is above a predetermined speed for example 7km / h, the solenoid valve S2 is in ON, the direct clutch C ₂ is in the released state, not in the reverse rotation state.

(G) Effects of the Invention As described above, according to the present invention, for example, 2
(S) At the start of a predetermined high speed other than the lowest speed, such as the second speed start of the range, the line pressure is set to be high in the predetermined high speed, so As a result, the engagement force of the frictional engagement elements that engage with each other can be ensured, and escape during stagging and starting on a snowy road can be performed accurately and reliably.

Specifically, a second control chamber (s) is provided in the cutback valve (59) in opposition to the _first control chamber (o ₁ ), and a hydraulic servo (B ₁₎ for the second coast brake is provided in the control chamber. ), The increased line pressure based on the cutback pressure can be applied to the hydraulic servo at the time of the second speed start in the 2 (S) range, and a strong engagement force is exerted. Starting on a snowy road can be performed accurately and reliably.

The cut-back valve (59) can generate a cut-back pressure at the start of the second speed as in the case of the first speed, but it is sufficient if the chamber for accommodating the spring (59b) is the second control chamber. The above function can be achieved at low cost without complicating the structure.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a main part of a line pressure control device in an automatic transmission according to the present invention and a cutback valve used therein. 2 is an overall sectional view of an automatic transmission to which the present invention is applied, FIG. 3 is a schematic configuration diagram thereof, FIG. 4 is a circuit diagram showing the hydraulic control device, FIG. 5 is each solenoid valve at each position, FIG. 4 is a diagram illustrating operating states of a clutch, a brake, and a one-way clutch. 1 ... automatic transmission, 3 ... transmission gear mechanism, 5 ... hydraulic control device, 52 ... primary regulator valve, 52a ...
… Main spool, 52b… Sub spool, 52c… Plug, e… Control room, f… Feedback pressure port, p ₂
...... line pressure port, h ...... secondary regulator valve port, _EX ...... drain port, i ...... throttle pressure (output corresponding pressure) port, j ...... cutback pressure port, d ₁ ...... R-range line pressure port, 53 ... output compatible (throttle) valve, 55 ... secondary regulator valve, 58 ... solenoid relay valve, 59 ... cutback valve, 59a ... spool, 59b ... spring,
j ₁ ... output port, q ... input port, o ₁ ... first control room, s ... second control room, B ₁ ... hydraulic servo for 2nd coast brake, B ₂ ... for 2nd brake Hydraulic servo, C ₀ ,
C ₁ , C ₂ , B ₀ , B ₁ , B ₂ , B ₃ ... hydraulic servo.

Continued on the front page (72) Inventor Takuji Taniguchi 10 Takane, Fujiimachi, Anjo, Aichi Prefecture Inside Ishin Warner Co., Ltd. (72) Inventor Hideo Tomomatsu 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) ) Inventor Sada Kondo 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Kunihiro Iwatsuki 1 Toyota Town Toyota City, Toyota City Inside Toyota Motor Corporation (56) References JP 62 −233554 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (5)

(57) [Claims] 1. A transmission gear device for changing to a plurality of gears by changing a transmission path, a hydraulic servo for a friction engagement element for engaging or disengaging a predetermined element of the transmission gear device, and a line for supplying the hydraulic servo. A primary regulator valve for adjusting the pressure, wherein the primary regulator valve is set such that the line pressure is higher at the lowest gear than at the high gear other than the lowest gear. In the apparatus, when starting at a predetermined high speed other than the minimum speed operated by the manual operation means, supply of the line pressure to a hydraulic servo for a high speed start frictional engagement element that directly engages a predetermined element. The primary regulator valve is set so that the line pressure becomes as high as the lowest speed, based on 2. A transmission gear device for changing a transmission path to a plurality of gears, a hydraulic servo for a friction engagement element for engaging or disengaging a predetermined element of the transmission gear device, and a line for supplying the hydraulic servo. A cut-back, which is used for a control device of an automatic transmission including a primary regulator valve that regulates pressure and a throttle valve that generates a throttle oil pressure corresponding to an engine output, and that generates a cut-back pressure at a predetermined shift speed. A valve, wherein the spool is biased in one direction, a first control chamber is disposed opposite the biasing direction, and a second control chamber is disposed in sequence in the biasing direction. An input port for inputting the throttle pressure, an output port for supplying the cut-back pressure to the primary regulator valve, and a drain port. A predetermined hydraulic servo to which hydraulic pressure is supplied is communicated with the first control chamber, and a second-speed engine brake hydraulic servo is communicated with the second control chamber. A cutback valve for use in a control device of an automatic transmission, wherein the cutback pressure is set to a higher value. 3. A transmission gear device for changing a transmission path to a plurality of gears, a clutch and a brake hydraulic servo for engaging or disengaging a predetermined element of the transmission gear device, and a line pressure supplied to these hydraulic servos. A control device for an automatic transmission, comprising: a primary regulator valve that regulates pressure, an output corresponding valve that generates a hydraulic pressure corresponding to an engine output, and a cutback valve that generates a cutback pressure at a predetermined shift speed. The cutback valve has a spool biased in one direction, and has a first control chamber opposed to the biasing direction, and a second control chamber along the biasing direction. An input port for inputting a hydraulic pressure corresponding to the engine output, and an output port for supplying the hydraulic pressure to the primary regulator valve or the output corresponding valve. A predetermined hydraulic servo, to which hydraulic pressure is supplied at the second speed or higher, is communicated with the first control chamber, and a brake hydraulic servo for regulating the coast state at the second speed is provided at the second control chamber. A control device for an automatic transmission, wherein the line pressure is set to be higher in the second speed coast regulation as in the case of the first speed, by communicating with the control room. 4. The output corresponding valve is a throttle valve that operates according to a throttle opening, and an output port of the cutback valve communicates with a cutback pressure port of the primary regulator valve. Item 4. A control device for an automatic transmission according to item 3. 5. A spool, a spring contracted at one end of the spool, a first control chamber formed at the other end of the spool, and a spring formed at one end of the spool and accommodating the spring. The cut-back valve used in the control device of the automatic transmission according to claim 3, further comprising a second control chamber having an input port, an output port, and a drain port.