JPS6231747A - Cut-back pressure control device in multistage automatic speed change gear - Google Patents

Abstract

PURPOSE:To satisfy shock tuning upon up-shift operation, by controlling a spool in a cut-back valve in accordance with a hydraulic pressure dependent upon the low speed operation of an auxiliary speed change unit and a hydraulic pressure dependent upon the operation of a main speed change unit at a speed stage above the second speed stage. CONSTITUTION:A cut-back control valve 43 comprises a spool 81 urged upward by a spring 82 and upper and lower oil chambers q2, G. The upper oil chamber q2 is communicated with an O/D direct clutch C0 in an auxiliary speed change unit through an oil passage q3, and the lower oil chamber G is communicated with a brake B2 which is cooperated with an one-way clutch to inhibit a sun- gear in a main speed change unit from rotating in one direction, through oil passages G2, G3. As a result, a cut-back pressure is cut off when the main speed change gear is operated at the first gear stage while the auxiliary speed change unit is operated at a low speed, but the cut-back pressure supply condition is maintained when the main speed change gear is operated at a stage above the second speed stage.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to an automatic transmission installed in an automobile, and more specifically to cutback pressure control in a multi-stage automatic transmission consisting of a main transmission unit and a sub-transmission unit. Regarding equipment.

(B) Prior Art Generally, an automatic transmission includes a torque converter and a planetary speed change gear mechanism, and the speed change gear mechanism includes an overdrive (0/D) planetary gear unit, a front planetary gear unit, and a rear planetary gear unit. The transmission gear mechanism achieves four forward speeds and one reverse speed through two solenoid valves and three shift valves.

In addition, conventionally, a cutback valve has been provided to apply cut bank pressure to the Scots 1 valve, and the cutback valve is applied to the 2nd brake B2 to which hydraulic pressure is supplied in 2nd gear and above. The cutback pressure is cut off in first gear and reverse gear, and the cutback pressure is supplied in second gear and higher gears.

On the other hand, as shown in Japanese Unexamined Patent Publication No. 57-37140, three solenoid valves and three shift valves are installed, and the front I The present applicant has devised a speed change control device that is used in combination with a main speed change unit consisting of a rear planetary gear unit and a rear planetary gear unit to obtain six forward speeds.

→ Problems to be Solved by the Invention By the way, the multi-stage 1tJJ transmission consisting of the sub-transmission and the main transmission unit has the sub-transmission unit having two overdrive and direct gears, and the main transmission having the first, second and third gears. Combining the 3 speeds to obtain 6 speeds, but when in the high speed state and the sub-transmission unit upshifts from direct connection to 0/D,
In other words, when the entire transmission shifts to 2nd speed, the conventional cutback valve does not supply cutback pressure, so the line pressure is set to a higher pressure than necessary in the throttle system.
This impairs the visual tuning during upshifting and causes unnecessary power loss due to the hydraulic pump.

Therefore, in the present invention, when the entire transmission is in second gear, z<y'
) FI ear ft1J small equipment and supply o,. Oh, it's a purpose.

(B) Means for Solving the Problem The present invention has been made in view of the above-mentioned circumstances, and the spool of the cutback valve is biased toward one oil chamber, and the auxiliary gear shift A predetermined friction retaining element to which hydraulic pressure is supplied when the unit is at low speed is connected, and the other oil chamber opposing the one oil chamber is connected to the main transmission unit;
When the main transmission unit is in 1st speed and the auxiliary transmission unit is in low speed, the cutback valve is activated by supplying hydraulic pressure to one oil chamber. Move the spool to block cutback pressure,
In addition, when the main transmission unit is in 2nd speed or higher, by supplying hydraulic pressure to the other oil chamber, the spool of the cutback valve is set to the cutback pressure supply position regardless of whether hydraulic pressure is supplied to one oil chamber or discharged. It is characterized by being held tightly.

Specifically, as shown in the first factor, the cutback valve 43 is pushed upward by the spool 81, which is biased upward by the spring 82. 1, which has an ltl chamber q2 and an upper oil chamber G, and the stage chamber q2 communicates with the O/D direct clutch C0 via an oil passage q3, and also has an upper oil chamber G (and an oil passage G). , G3, the one-way rotation of the sun gear 30 (see Fig. 8) in the main transmission unit is controlled by the one-clutch F1.
It communicates with brake B, which works together with brake B to prevent this.

(E) Operation Based on the above configuration, when the transmission 1 is in the first gear as a whole,
That is, the sub-transmission unit 16 is the O/D direct clutch C.
0 is engaged and in a directly connected state, and the main transmission unit 21
When the forward clutch C1 is engaged and is in the first speed state (see Fig. 6), line pressure due to the engagement of the clutch C0 acts on the cutback valve 43 on its stage chamber q2, and the stage chamber Boat a2 and G are cut off by the first shift valve 51, and no hydraulic pressure is applied to G. Therefore, in this state, the cutback valve 43 is in the left half position in FIG. 1, the spool 81 moves downward against the spring 82, and boats
No pressure is supplied to the rough throttle valve 41. Furthermore, in reverse (see Figure 12), N range and P range, the O/D direct clutch C
Since hydraulic pressure is supplied to brake B and brake B is not engaged, cutback valve 43 operates in the same manner as described above.

When the entire transmission shifts from 1st speed to 2nd speed, the main transmission unit 211 maintains the 1st speed state with the forward clutch C3 engaged, and the auxiliary transmission unit 211 maintains the 1st speed state with the forward clutch C3 engaged.
16, the brake B0 is engaged and the 0/D direct clutch C0 is disengaged as the brake B0 is engaged and the 0/D direct clutch C0 is released (h'l) to upshift from direct connection to 0/D (Fig. 7). As the O/D direct clutch C0 is released, the oil pressure in the performance room q is drained from the pressure pump valve 43.
The spool 81 of is moved upward by the spring 82 (to the left half position in Figure 1), and the boats x and p are communicated with each other.
Cutback pressure is supplied from p, pushing back the spool 79 against the spring 76, and setting the throttle pressure low.

Furthermore, when the entire transmission shifts from 2nd to 3rd speed, the main transmission unit 21 engages the brake B outside the I/Warder CI and enters the 2nd speed state, and the auxiliary transmission unit 16 (At the same time as brake B is released, clutch C8
is engaged and the brush shifts from O/D to direct connection. (8th
(See Figure 3). Then, hydraulic pressure is supplied to both the performance chamber q2 and the performance chamber G of the cutback valve 43, but at this time, the upward biasing force by the spring 82 and the performance chamber G overcomes the downward biasing force by the performance chamber q2, and the spool 81 is held at the upper position (left half position) to maintain communication between boats x and p. Similarly, the entire transmission has 4
5th, 5th, and 6th gears, the brake B2 of the main transmission unit 21 remains engaged, and the direct clutch C0 of the first transmission unit 16 switches between engagement and disengagement, but there is no cutback. The valve 43 is set to the cutback pressure supply position (left half position) based on the fact that hydraulic pressure should continue to be supplied to the stage room G regardless of whether hydraulic pressure is supplied or drained to the stage room as the clutch C0 is engaged or released. ) is held.

(f) Example Embodiments of the present invention will be described below along with the drawings.

As shown in FIG. 2, the multi-stage aa transmission 61 includes a torque converter 2, a planetary transmission gear mechanism 3, and a hydraulic side aa mechanism 5, each of which has a converter house synchronizer,
1-Transmission case 7 and extension housing 9, and valve body lO and oil pan 1
It is stored in 1. The torque converter 2 includes a lock-up clutch 12, and transmits the rotation of the input member 13 via the oil flow of the torque converter 2 or directly by the lock-up clutch 12 to the input shaft 15 of the transmission gear machine H1t3. The transmission gear machine HIt3 is overdrive (0/
D) Consists of a Wl transmission unit 16 consisting of a planetary gear unit 17 and a main transmission unit 21 consisting of a front planetary gear unit 19 and a rear planetary gear unit 20. 0/D planetary gear unit 17
The planetary gear 22 is directly connected to the input shaft 15, the sun gear 23 is fitted onto the input shaft 15, and the ring gear 25 is connected to the input shaft 26 of the main transmission unit 21. An O/D direct clutch C9 and a one-way clutch F0 are interposed therebetween, and an O/D brake B0 is provided between the sangya 23 and the case 7. The front planetary gear units 1 to 19 also include a planetary gear 29 directly connected to the output shaft 27, a sun gear 30a1 that is fitted onto the output shaft 27 and is integrated with the sun gear 30b of the planetary gear unit 20, and an input axis 26
A direct clutch C2 is interposed between the input shaft 26 and the sun gear 30, and a coast brake B1 is connected between the sun gear 30 and the case 7.
is interposed between the sun gear 30 and the case 7, and a one-way clutch F is interposed between the sun gear 30 and the case 7.

A brush B2 for locking the outer race of the clutch Fl is also provided. Further, the rear planetary gear unit 2θ includes a planetary gear 31, a sun gear 30b, and a ring gear 32 directly connected to the output shaft 27.
Further, the planetary gear 31 and the mouthpiece 35 are oil pumps.

Notches or holes are formed at equal intervals in the flange piece 23a on which the sun gear 23 is installed or connected to the sun gear 23. Therefore, the rotation sensor A detects the rotational speed of the sun gear 23, that is, the shift operation state of the sub-shift unit 16. In addition, a rotation sensor A2 is also installed in the case 7 of the front planetary gear unit I/19 part, and a BA connection piece 3O extending from the sun gear 30 is also installed.
Notches or holes are also formed at regular intervals. Therefore, the rotation sensor A2 detects the rotation speed of the sun gear 3o, that is, the operating state of the main transmission unit 21.

On the other hand, hydraulic gear shifting! &1TtIIH45 consists of many valves, accumulators, orifices 36, strainers 37, etc., as shown in Fig.
Tell me about 1 rube. The manual valve 4o is switched to each range of P, R, N, D, S, and L by the lever, and each range is 1 Tbua as shown in Fig. 1.
, b, c, d, and e are switched. Note that line pressure is supplied to the oil passage e. The throttle valve 41 includes a downshift plug 42, and a cam rotates in response to depression of the accelerator pedal to obtain a throttle pressure corresponding to the engine output. The cut puncture valve 43 generates cutback pressure, which will be described later, and acts on the throttle valve 41. Primary regulator valve, 1
5 is regulated by the throttle pressure and generates line pressure corresponding to the load. That is, when the load is actual, the line pressure is increased to ensure the working pressure of the clutches C and brake B, and when the load is light, the line pressure is regulated to a lower level. The secondary regulator valve 46 is regulated by the hydraulic pressure from the primary regulator valve 45 and controls converter hydraulic pressure and lubricating hydraulic pressure supplied to the converter 2 and each lubricating section 47 . Lock-up relay valve 49 is solenoid valve S
Controlled by L, switch the oil flow leading to the lock-up clutch 12 and oil cooler 50. That is, by turning on the solenoid valve SL, line pressure is applied to the upper end oil chamber e', thereby switching the converter hydraulic oil path f from the primary regulator valve 45 from the lock-up clutch off oil path g to the on oil path, Drain converter hydraulic pressure. The first shift valve 51 switches the main transmission unit 21 between 1st speed and 2nd speed (1st speed and 3rd speed as a whole of the shift BIt1), and is operated by a solenoid valve s1. That is, when the solenoid valve SI is turned off, line pressure is applied to the oil chamber and is supplied to the manual valve 4° brake B2 and B2 accumulators B and A. The second shift valve 52 switches between 2nd speed and 3rd speed (3rd speed and 5th speed for the entire transmission) of the main transmission unit 21, and is operated by a solenoid valve S2. That is, when the solenoid valve S is turned off, line pressure is applied to the oil chamber k, and the line pressure oil passage e is connected to the oil passage m, so that the direct clutch C2
Supply line pressure to C2A, and connect the solenoid valve (O, valve S2) to the 1st 3rd valve.
1 to 753 are sub-shifts -7-S:・1・161
il/switching round rotor), ・Runo 1' de valve S3
activated by

That is, the pressure is applied to the oil chamber n by the nonoid pulse S, and the pressure oil passage 61' is communicated with the oil passage 0. B, Release control! - O/D brake B via roll valve G5.
゛By turning off valve S, line pressure oil passage I is passed (]:
This connects the line pressure to the O/D direct controller 7-1c.
o and C. It communicates with accumulator C6A.

The first coast valve 55 is operated by the manual valve 1--
Ki B: . The second coast modifier Balu 156 is the S range of the manual valve 40, and is the 3rd in history.
5: Ni1-Stomogoyyu and supply one sweat to -f L, -Kimi. The first accumulator controller 57 supplies the pressure to the 27th accumulator, which will be described later, -! - pressure e supplied through the valve 70;
Accumulate the pressure to the control pressure, and
Trol pressure B0 accumulator B. A, C27 Ki...
,.

Each i= of the ratio C2A and B2 accumulator 1/-
” in the pressure chamber 5, and pick up 1 in 60 and 61.

Furthermore, in addition to the above-mentioned hydraulic equipment, this hydraulic transmission control system 5
So modulator valve 65. B.

Release control 1-roll valve 66,B;-ke:,,,
knee, valve 67, lockup control valve l
'j9 andhiffi 2 Akyumurakkon 1 ~ Rono 1. A valve 70 is attached.

So Monulator Valve 65! As shown in detail in FIG. 4, line pressure is supplied from the line pressure port 11 via the oil strainer 37, and is further communicated via the oil 18s to the upper end oil chamber s1. The feedback pressure acting on the spring 7] is balanced and regulated to a predetermined pressure (for example, 4 kg/cIIl), and the regulated solenoid modulator pressure is supplied to the passage t.

Furthermore, the solenoid valve S is connected to the oil passage t1 through the plug 72 and the passage t.

It also communicates with the Bo series control harness.
! , communicates with Pro 6, solenoid valve S.

Control pressure by on/off control or duty control is supplied to the oil chamber t2, and the control valve 66 is controlled. In addition, solenoid valve S. is rotating Senisa A,,
Based on A2 (L-controlled by the signal from the cylinder control section E,
When the valve S0 is under on/off control, the throttle pressure is supplied to the oil '15X5, and the brake release pressure is set according to the load change. Furthermore, said B. The boat y of the release control valve 66 is connected to the 0/D brake B via the oil passage y1. and B0 Aki, Mureta B. It communicates with A and has orifice 369! In addition, the oil passage yl communicates with the boat y of the sequence valve 67 via a bypass passage y5 at its tip end, and furthermore, The feedback pressure in the oil chamber y4 is balanced with the spring 80 at the upper end, and the spring 80 is connected to the O/D brake B. The sequence valve 67 is set to the initial operating pressure of the piston at which the brake plates of 1 and 2 start contacting each other, and therefore, the sequence valve 67 is in the left half position until the initial operating pressure and the O/D brake B passes through the boats 12 and 2.
When hydraulic pressure is supplied to 0 and exceeds the initial operating pressure, it is switched to the left half position and ports z and y- are closed to rA. In addition, Boat Z of Con 1 to Roll Pulp G6 is hh
9z and orifice 3G to port l-o of the third shift valve 53, and is further connected to the port l-o of the third shift valve 53.
B via bypass path L5. It communicates with port l-z 2 of the sequence valve lower, and oil passage Y6, which branches from oil passage y, connects to oil passage Z via check valve 72.
.

is connected to. On the other hand, the upper chamber n of the third shift valve 53 communicates with the solenoid valve S3, the boat e communicates with the line positive, and the boat q communicates with the oil passage q.
, and 0.0 through orifice 36. 'D communicates with direct clutch C0 and C0 accumulator CoA. Note that a clutch C8 is connected to the orifice 36 of the oil passage q1.
A check valve 75 is interposed in parallel to allow discharge from the air. Further, d in the figure is a drain bow 1.

In addition to controlling the conventional main transmission unit 21 to enable lock-up when the main transmission unit 21 is in 2nd gear or higher, the lock lub control valve 69 also controls the sub-transmission unit 16 in the O/D state even when the main transmission unit 21 is in 1st gear. When the transmission is in the second gear or higher, that is, when the transmission as a whole is in second gear or higher, control is performed so that lockup is possible. Furthermore, when the 11th transmission unit 16 is in the 0/D state and the main transmission unit 21 upshifts, the second accumulator control valve 70 controls the main Accumulator B because the variable speed brake capacity is excessive. A, C2A, B2A back pressure chambers 59, 60
, 61 to optimize the brake capacity.

As shown in FIG. 1, the cut valve 43 has a spool 81 that is urged upward by a spring 82, and a stage chamber q2 is located at the upper end of the spool 81.
Furthermore, a performance chamber G is arranged at the lower end of the spool 81 in which the spring 82 is contracted. Further, the stage room q2 communicates with the oil passage ql to the O/D direct clutch C0 via the oil passage q, and the stage room G communicates with the boat G of the first shift valve 51 through the oil passage G2. , and the boat G further communicates with a brake B2 and a B2 accumulator B2A via an oil passage G3. Throttle pressure is supplied from the throttle valve 41 to the boat X of the cutback valve 43, and the applied pressure is applied to the throttle valve as cutback pressure via the boat P, which is communicated or shut off by switching the valve 41. 41 boat Pl#p2. The throttle valve 41 includes a downshift plug 42 operated by a throttle cam 44 linked to an accelerator pedal, and a downshift plug 42 that is disposed via the plug 42 and a spring 76 and urged upward by a lower spring 77. The throttle cam 44 has a throttle spool 79 that
Based on the rotation of C spool 7 via spring 76
9 moves downward, pressure corresponding to the throttle opening is supplied from the line boat e to the throttle boat x3. Further, the throttle pressure acts on the boat X4, and the cutback pressure acts on the boat p1,
These pressures push back the spool 79 against the spring 76 based on the difference in the land diameter of the spool 79, and when both springs 76 and 77 are balanced, the line boat l is closed. Therefore, the throttle pressure corresponds to the throttle opening and vehicle speed. The hydraulic pressure is as follows. In addition, the downshift plug 42
The hydraulic pressure from the boat X2 acts on the lands 42a, 42b (42a>42 bl) of the downshift plug 42,
Land 42 due to cutback pressure acting on porthole 2
b, 42c (42b>42c), the pressing of the springs 76, 77 against the throttle cam 44 reduces the force.

Note that the bow 1-a of the cutback valve 43 communicates with the boat a of the manual valve 40, and the bow switched by the boat a1 and the valve 43) u I
The f-lock valve control valve 6 is passed through. Further, oil path a from boat a is connected to forward clutch C.
and communicates with the boat a2 of the first shift valve 51. Further, the boat F2 of the first shift valve 51 communicates with the boat F1 of the third shift valve 53, and the boat H of the valve 51 communicates with the first coast monulator valve 5.
5, the boat ■ is in communication with the brake B3, the boat J is in communication with the second coast mosh L-ta valve 56, and the boat is in communication with the second shift valve 52, respectively.

Next, the operation of this embodiment will be explained.

Each solenoid valve S of this multi-stage automatic transmission 411.

B2, B3, sL, so, each clutch C0, C. ．． c2
, brake B0t B,, B3, and each one-way clutch F0, F,, F, are connected to each body P, R, N.
,D.

At the S and L gears, the gears are controlled as shown in the operation table shown in FIG.

That is, in 1st gear in D range or S range, as shown in FIG. 6, 0/D direct clutch C and one-way clutch F. , F2 and forward clutch C3 are engaged, and the others are in a released state.

Therefore, the C1 auxiliary transmission unit I.]6 is directly connected to the planetary gear unit 17 via the clutch C1 and the one-way clutch F0, and is directly connected to the input shaft 1.
5 should be transmitted as is to the input shaft 26 of the main transmission unit 21. In addition, the main transmission unit: 260 revolutions of the input shaft is transmitted to the ring gear 3 of the front planetary gear unit 19 via the clutch C4, and further to the planetary gear 29 and the output shaft 27 integrated with the gear 29.
At the same time, a leftward revolving force is applied to the planetary gear 31 of the rear planetary gear unit 20 via the sun gear 30, but the revolution is stopped at the one-way corner F2, and the gear 31 rotates on its own axis. Power is transmitted to a ring gear 32 that is integrated with the output shaft 27. That is, the main RW unit 21 is in the 1st speed state, and the sub transmission units 1 to 1 are in the 1st speed state.
Together with the direct connection state of 6, the entire transmission is in the 1st speed state. At this time, the main transmission unit 21 connects the output shaft 27 from the planetary gear unit 19 to the output shaft 27 via the rear planetary gear unit 20.
It is branched into systems, and the load that the gears can take is distributed accordingly.

In the 1st speed state of MOSI-CS, solenoid valve S.

is in the OFF state (therefore, the third shift I valve 53 is in the left half position, and the line pressure of LISIBO-1-/ is applied to the O/D clutches C6 and C via the boat q and the oil passage q1.

Ai is supplied to Yum Lake C9A, and oil line q.

・Kali through 2! - The stage room q of the back valve 43 is supplied first. On the other hand, the noid valve S is also in the off state, and the first shift valve 51 is in the left half position.
In the manual valve 40, the line pressure from the light report e is supplied to the forward clutch C1 via the line pressure a, but the boat a2 is blocked at the seat valve 51, and the line pressure is connected to the brake B2. And no hydraulic pressure acts on the stage chamber G of the cut bank valve 43. Therefore - ζ, cut valve 43i, f.

Based on the oil pressure in the stage room q2, the spool 81 moves against the spring 82 and is in the left half position, boats x and p are cut off, and no cutback pressure is supplied to the throttle valve 41.

Further, in the second speed in the D range or the S range, as shown in FIG. 7, the O/D brake B0, one-way clutch F2, and forward clutch C are engaged, and the others are in the M released state. Therefore, the sub-transmission unit)-16 is
The sun gear 23 is locked by the brake B0, and the planetary gear 22 rotates and transmits power to the ring gear 25, and transmits increased rotation (0/D) to the input shaft 26 of the main transmission unit 1.21. In addition, the main transmission unit)・21
This is the same as the previous one-speed state, and therefore, the first speed of the main transmission unit 21 and the speed increase of the sub-transmission unit 16 combine to bring the entire transmission into the second speed state.

This 1m, as shown in Figure 4, solenoid valve S
is turned on, and the third shift valve 53 is turned on. When line pressure is supplied to the line pressure, the state changes to the state shown in the left half diagram. Then, pressure oil in clutch C8 and C0 Akiuni, 2-way C0A is discharged from boat q to drain port d, clutch C is released, and the line pressure from boat 0 is discharged to the Bo piston. Initial operating pressure or sequence valve 67 port) - Z2pY
3 and oil EyS directly to the 0/D brake B0, and when the initial operating pressure of the B0 piston is exceeded, the oil chambers y and l
The valve 67 is blocked by the feedback pressure of 19! , and then the line pressure from boat 0 is supplied to boat Z of 80 release control valve 66 via orifice 36 and oil passage 17. Furthermore, in this state, the coretrol valve 66 is in the left half position,
Boat B and y communicate with each other, and buoy pressure is applied to brake B via oil passage y.

and B0 accumulator B. A is supplied to engage brake B0.

In the second speed state, based on the drain of the O/D crunch C0, the cant-back valve 43 is moved to its stage chamber q2.
5. The hydraulic pressure has been drained, and the first shift I bell 51 is held in the left half position, so that no hydraulic pressure is applied to the stage room G. Therefore, the force y1 - the back valve 43,
82, the spool 81 is returned upward to the left half position in FIG. 1, and the balls l-x and p are communicated with each other. As a result, the throttle pressure from port X acts on ports p and pp2 of throttle valve 41 via port p,
The spool 79 is pushed back against the spring 76 to lower the throttle pressure by a predetermined amount, and the pressing force of the downshift plug 42 against the throttle cam 44 is reduced. As shown in Figure 8, O/D clutch C8 and one-way clutch F. , forward clutch C1, one-way clutch F, and brake B2 are engaged, and the others are in a released state. Therefore, the sub-transmission unit 16 is in the above-mentioned directly connected state, and the input shaft 1
5 is directly transmitted to the input shaft 26 of the main transmission unit 21.

Further, in the main transmission unit 21, the rotation of the input shaft 26 is transmitted to the ring gear 31 of the front gear unit 31 via the clutch C, and the rotation of the input shaft 26 is transmitted to the ring gear 31 of the front gear unit 31 via the planetary gear 29.
However, the gear 30 is prevented from rotating in this direction by the one-way clutch F when the brake B2 is engaged, and therefore the planetary gear 29 revolves while rotating, and the front gear Second speed rotation is transmitted to the output shaft 27 only via the unit 29. As a result, the direct connection state of the sub-transmission unit 16 and the direct connection state of the main transmission unit 21
Together with the second speed state, the transmission 1 as a whole can obtain the third speed.

At this time, the solenoid valve S is turned on and the first valve I.
Switch the valve 51 to the left half position in Figure 1, and set the bow 1-a2.
The line pressure is communicated to port Gl, and the line pressure is supplied to brake B2 and accumulator B2A. At the same time, as shown in FIG. 4, the excitation of the made valve S3 is released and the third shift valve 5g+r is switched to the right half position. Then, the line pressure boat e communicates with the port q, line pressure is sent to the clutch C0 and the C0 accumulator C:C1A via the oil passage q, and the clutch C0 engages, and the line port 1 and the port o Communication with is closed.

Furthermore, prior to engagement of the clutch C0, a rotation sensor A,
and A2, the solenoid valve S0 is duty-controlled or on-controlled by an electric signal from the control unit E based on A2, thereby reducing the modulator pressure in the oil passage t.

That is, the S modulator valve 65 regulates the line pressure of the line boat e using the spring 71 and the feedback pressure of the stage room S, and supplies it to the oil passage t, but the modulator pressure is controlled by the solenoid valve S0. The pressure in the stage chamber t2 of the B release control valve 66 communicating with the oil passage t is also reduced. Therefore, the control valve 66 is placed in the left half position 2 in FIG. 4 while receiving the pack pressure from the brake B0 in the stage room y2, and the brake B is applied. and Accumulator B. A
The hydraulic pressure from the drain boat d is discharged to the drain boat d via the oil passage y1 and the port y. This causes 0/D brake B.

The release operation of brake B2 corresponds to the engagement operation of brake B2.

In the third speed state, the cutback valve 43 is
Stage room q2 based on oil pressure supply to 0/D clutch C6
At the same time, hydraulic pressure is applied to the stage room G via the oil passage G2 based on the supply of hydraulic pressure to the brake B2, but the hydraulic pressure to the stage room G and the upward biasing force by the spring 82 are applied to the stage room q2. Therefore, the spool 81 is held in the upper left half position in FIG. 1, which is the upper position. In this state, T←T→-tearza pressure is supplied to throttle valve 4 cuff t\turn 1 as in the case of 2nd speed.

Further, at the fourth speed in the D range, as shown in FIG. 9, the 0/D brake B0, forward clutch C1, brake B2, and one-way clutch F are engaged, and the others are in a released state. Therefore, the auxiliary transmission unit 16 is in the speed increasing (0/D) state mentioned above, and the main transmission unit
It is in the 1st and 2nd gear state, which causes the shift to 8I! 1. 4 speeds are obtained as a whole.

In the 4th speed state of C1, the cutback valve 43 drains the stage chamber q2 with the release of the O/D clutch C0, but the first shift valve 51 is held at the left half position in FIG. Based on the fact that the line pressure from port a is supplied to the stage room G, there is a cutback pressure supply position where bows 1-x and p communicate with each other.

Further, at the fifth speed in the D range, as shown in FIG. 10, the O/D clutch C0, one-way clutch F0, forward clutch C1, direct clutch C2, and brake B2 are engaged, and the others are in a released state. Therefore, the auxiliary transmission unit 16 is in the above-mentioned direct connection state, and the main transmission unit 21 is integrated with the front brake gear unit 19 by engagement of the clutches C, C2.
The rotation of the input shaft 26 is transmitted directly to the output shaft 27.

As a result, the direct connection of the sub-transmission unit 16 and the third speed of the main transmission unit 21 combine to provide a fifth speed in which the input shaft 15 and the output shaft 27 rotate integrally as a whole of the transmission 1.

Even in the fifth speed state, the solenoid S is in the on state, the first shift valve 51 is still in the left half position, and the cutback valve 43 continues to have hydraulic pressure supplied to its main oil chamber G. Even if oil pressure is supplied to the main oil chamber q2 based on the engagement of the O/D clutch C9, the cutback pressure supply position is maintained at the left half position.

Also, when in 6th gear at D and G, the 0/D brake B is applied, as shown in FIG. , the forward clutch C1, the left clutch C2, and the brush B2 are engaged, and the others are in the released state. Therefore, the auxiliary transmission unit 16 is in the above-mentioned directly connected state, and the main transmission unit 21 is also in the above-mentioned 3rd speed state, and these two transmission units 1-16,
21 together, the transmission 1 as a whole obtains 6 speeds.

Even in the sixth speed state, the first shift valve 51 is in the left half position, and the cutback valve 43 is held at the cutback pressure supply position by the hydraulic pressure acting on the oil chamber G.

Brake B3 is engaged, and the others are in a released state. Therefore,
The auxiliary transmission unit 16 is in a directly coupled state, and the main transmission unit 21 has the rotation of the input shaft 26 directly transmitted to the sun gear 30 by the clutch C2, and the revolution of the rear planetary gear 31 is locked by the brake B.
The rotation of the sun gear 30 is transmitted as reverse rotation to the link gear 32 via the rotation of the planetary gear 31, and the output shaft 27
In the reverse state, the manual valve 40 is switched to the R range, so that line pressure is no longer supplied to the boat a, and the lunoid S is set to τ7 and the first shift valve 51 is The brake is switched to the left half position, so that the hydraulic pressure of the brake B2 is drained and the lower reservoir chamber G of the cut bank valve 43 is also drained. On the other hand, the third solenoid valve is in the off state, the third shift valve 53 is in the left half position, and the oil pressure of the line pressure boat 1-1 is in the boat q
It is supplied to the O/D Kurasochi C6 via (7), and is also supplied to the main oil chamber q2 of the back valve 43.

Therefore, the cut bank valve 43 is in the left half position in FIG. 1, as in the 1st speed state, and the BO! -x's throttle pressure is cut off and boat pp P Ie p2's cutback pressure is drained.

In addition, in P range and N range, 17th L)・
'Do S and the third nozzle S are both in the OFF state, so the cutback valve 43 is also held at the cutback pressure cutoff position, similar to the R range.

In addition, during 3rd and 4th speeds in the S range or L range, the coast brake B is engaged in the 3rd and 4th speeds of the D range mentioned above (see Figures 8 and 9). , Therefore, rotation of the sun gear 30 is prevented in both directions,
Engine braking is possible. At this time, when shifting from 2nd speed to 3rd speed, solenoid valve S is activated as in the D range. is controlled so that the sub-transmission unit 16 and the main transmission unit 21 are simultaneously shifted. ), the brake B3 is engaged, and therefore the revolution of the rear planetary gear 31 is prevented in both directions, making engine braking possible.

Note that the cutback valve 43 in the 3rd, 4th, 1st, and 2nd speeds in the S range and L range is the same as in each shift in the D range.

In addition, in the above embodiment, the sub transmission unit 16 is located in the front gear, and the main transmission unit 21 is located in the rear stage. Of course, the present invention can also be similarly applied to a front-wheel drive horizontal automatic transmission in which the auxiliary transmission unit is located at the rear stage.

(G) As described in detail, according to the present invention, the sub-transmission unit 1
6 and the main transmission unit 21, multi-stage shifting can be performed. However, since the cutback pressure acts on the throttle valve 41 in the second gear or higher in the entire transmission 1, the throttle valve 41 In the official history, the line pressure is not set to a higher pressure than necessary, and power loss due to the hydraulic pump 35 can be reduced, and shift tuning at the time of upshifting can be prevented from deteriorating.Furthermore, in the cutback valve 43, , an oil chamber G to which hydraulic pressure is supplied in the second and higher gears of the main transmission unit 21.
In order to counteract this, it is sufficient to install an oil chamber q2 that supplies hydraulic pressure to the sub-transmission unit 16 at low speed. Cutback pressure can be supplied by using an overdrive planetary gear unit νI.17 as the FA'JR speed unit 16, a front planetary gear unit as the main transmission unit I.21, and a cut bank valve. One oil chamber q of 43.

The Opa Drive Planetary Gear 1″17 Gui Shiri J・
It communicates with clutch C0, and the other oil chamber G is connected to Freon j.
When connected to the brake B2 that prevents one-way rotation of the Sanogya 30 of Multi-stage automatic transmission 8!1 can be provided at low cost without major changes.

[Brief explanation of drawings]

Fig. 1 is a diagram showing a lift/back pressure control device according to the present invention, Fig. 2 is an overall sectional view showing an automatic transmission to which the present invention is applied, and Fig. 3 is a hydraulic control mechanism thereof. Overall view,
FIG. 4 is a diagram showing the main parts of the hydraulic control mechanism, and FIG. 5 is a diagram showing the operating state of each device in each position. FIGS. 6 to 12 are diagrams showing the operation of the automatic transmission in different states. 1... Multi-stage automatic transmission, 2... Torque converter, 3... (Planetary) speed change gear mechanism, 5...
・Hydraulic control mechanism, 16... Sub-transmission unit, 1
7. Overdrive Plane Clear Gear Unit, 1
・Front planetary gear unit 20... Rear planetary gear unit, 21... Main transmission unit, 4
1... Throttle valve, 43... Cutback valve, 51. 52, 53...ft valve, 81...spool, 82...spring, Bo, B2, B3...
Frictional engagement element (brake), B2...predetermined frictional engagement element (brake), C0, C,, C,...1'J f
il engagement element (clutch), C0...predetermined friction retention element (0/D direct clutch), s,, s2,
s,, sl. so solenoid valve, so
...Solenoid valve, q2- (Y) oil chamber, G- (
Bottom) Oil room applicant Ain Warner Co., Ltd. TOYOKUJI! I!
[1 Car Co., Ltd.

Claims (2)

[Claims] (1) A transmission gear mechanism that has a sub-transmission unit and a main transmission unit, and obtains multi-stage transmission by a combination of these transmission units based on controlling a frictional engagement element that switches the transmission line of each of these transmission units. and a hydraulic control mechanism having a shift valve, a solenoid valve, a manual valve and a throttle valve that control each frictional engagement element of the transmission gear mechanism, and a cutback valve that applies cutback pressure to the throttle valve. In the multi-stage automatic transmission, a predetermined frictional engagement element biases the spool of the cutback valve toward one oil chamber and supplies hydraulic pressure to the one oil chamber when the sub-transmission unit is at low speed. and a predetermined frictional engagement element to which hydraulic pressure is supplied in the second or higher gears of the main transmission unit is communicated with the other oil chamber opposing the one oil chamber, so that the main transmission unit is in the first gear. and when the auxiliary transmission unit is at low speed, hydraulic pressure is supplied to one of the oil chambers to move the spool of the cutback valve to cut off the cutback pressure, and when the main transmission unit is at 2nd speed or higher, the other Cutback pressure control in a multi-stage automatic transmission, in which a spool of a cutback valve is maintained at a cutback pressure supply position by supplying hydraulic pressure to one oil chamber, regardless of whether hydraulic pressure is supplied to or discharged from one of the oil chambers. Device. (2) The auxiliary transmission unit is an overdrive planetary gear unit, the main transmission unit includes a front planetary gear unit and a rear planetary gear unit, and the predetermined frictional engagement element of the auxiliary transmission unit is a direct transmission element of the overdrive planetary gear unit. 2. The multi-stage transmission according to claim 1, wherein the multi-stage transmission is a clutch, and the predetermined frictional engagement element of the main transmission unit is a brake that locks an outer race of a one-way clutch that prevents unidirectional rotation of sun gears in front and rear planetary gear units. Cutback pressure control device in automatic transmission.